Skocz do pozycji: 1.

Tytuł:

Respiration and oxygen status during bud burst of grapevine

Autorzy:

Meitha, K.
Konnerup, D.
Considine, J.
Foyer, C.
Colmer, T.
Considine, M.

Powiązania:

https://bibliotekanauki.pl/articles/79925.pdf

Data publikacji:

2013

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

conference
grapevine
respiration
bud burst
grape-vine
temperature
photoperiod
oxidative burst

Źródło:

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796

Pojawia się w:

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 2.

Tytuł:

2-Repeated Solid Burst Error Detecting Cyclic Codes

Autorzy:

Rohtagi, Barkha

Powiązania:

https://bibliotekanauki.pl/articles/1159230.pdf

Data publikacji:

2018

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Repeated solid burst errors
burst error detection
cyclic codes
parity-check digits

Opis:

In modern era, coding theory has found various applications in almost every field whether it is theoretical or practical. Such as: digital data transmission, medical science, space science, geographical sciences etc. It is natural that bursts have different behavior in different channels. But the burst errors are found to occur mostly in various communication channels. In some of the systems, lightening and other short term irregular disturbances introduce various types of repeated burst errors. Usually they operate in such a way that over a specific length, some digits in a message are received correctly, while all other are corrupted. It is very common in some extra noisy channels that all the digits in a burst are corrupted. Such type of errors is called ‘solid burst errors’. It may also be mentioned that cyclic codes play a significant role in error detection and correction. In this paper, we obtain results for cyclic codes that are capable of detecting 2-repeated solid bursts of length b.

Źródło:

World Scientific News; 2018, 113; 44-48
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 3.

Tytuł:

The Solar Radio Burst Type II Correlated With Minor CME Contributes to The Production of Geomagnetic Disturbance

Autorzy:

Husien, Nurulhazwani
Hamidi, Z. S.
Ali, M. O.
Zainol, N. H.
Sabri, S. N. U.
Shariff, N. N. M.
Faid, M. S.
Ramli, Nabilah
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/1192691.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Solar radio burst
solar radio burst type II
Coronal Mass Ejections
geomagnetic disturbance

Opis:

The solar radio burst type II on 4th November 2015 was associated with minor CME that not lead towards the Earth. This clear type II burst recorded on spectrographs detected by the antenna in several locations (Gauri, Almaty, Kasi and Ooty) were obtained from CALLISTO website. The average time of the burst occurred are around 03:24 UT until 03:28 UT with the clear minor CME emerged recorded by SOHO at 03:12 UT. Although it just a minor CME but it is still giving the effect on Earth as it contributes to geomagnetic disturbance on the Earth during that day. The affected region reported by The Local news is Sweden, where the radar system for aviation was not clear, but it is back to normal after a few hours later. This geomagnetic disturbance is powerful enough that may cause the satellite damage, endanger astronauts and produce destructive surges on power grids.

Źródło:

World Scientific News; 2016, 46; 165-175
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 4.

Tytuł:

On Detection and Correction of 2-Repeated Solid Burst Errors

Autorzy:

Rohtagi, Barkha

Powiązania:

https://bibliotekanauki.pl/articles/1070849.pdf

Data publikacji:

2019

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

2-repeated solid burst errors
parity-check matrix
solid burst errors
standard array and syndrome

Opis:

In modern age, coding theory has found widespread theoretical and practical applications in the areas ranging from communication systems to digital data transmission to modern medical science, to space communication. In different types of channels, nature of errors is also different. There are various channels in which errors occur in the form of bursts. In some particular channels, within a burst, all the digits are corrupted. Such type of errors is called ‘solid burst errors’. In this paper we introduce ‘2-repeated solid burst error’ and obtain results regarding the codes detecting and correcting such errors.

Źródło:

World Scientific News; 2019, 123; 76-86
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 5.

Tytuł:

Production of Coronal Mass Ejections in Relation With Complex Solar Radio Burst Type III Correlated With Single Solar Radio Burst Type III

Autorzy:

Hussien, Nurul Hazwani
Hamidi, Z. S.
Ali, M. O.
Sabri, S. N. U.
Zainol, N. H.
Shariff, N. N. M.
Moinstein, C

Powiązania:

https://bibliotekanauki.pl/articles/1192988.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Sun
Solar radio burst
type III
single Solar Radio Burst Type (SRBT) III
complex Solar Radio Burst Type (SRBT) III
Coronal Mass Ejection (CMEs)
magnetic reconnection

Opis:

The complex solar radio burst type III is very related to generation of Coronal Mass Ejections (CMEs). In a previous study, they deduced that the burst was produced by electron beams accelerated in blast wave shocks and injected along open magnetic field lines, similar to the herringbone bursts at metric wavelengths. Usually, if there is another solar flare recorded during complex solar radio burst type III it should be type II burst. Different for this event, the single solar radio burst recorded occur 8 minutes 30 seconds before the complex solar radio burst type III. The Coronal Mass Ejections also recorded occurred 7 hours before the single and complex solar radio burst type III. It is noted that CMEs occurred several hours before this event recorded by the SOHO websites.It is proved that the production of coronal mass ejection contributed to the production of complex solar radio burst type III.

Źródło:

World Scientific News; 2016, 36; 96-108
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 6.

Tytuł:

Solar Radio Burst Type III due to M 2.9 Class Flare with a Geomagnetic Disturbance

Autorzy:

Hamidi, Z. S.
Ali, M. O.
Shariff, N. N. M.
Monstein, C.
Zainol, N. H.
Hussien, Nurul Hazwani
Ramli, Nabilah
Farid, M. S.

Powiązania:

https://bibliotekanauki.pl/articles/1190207.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

solar radio burst
solar storm
flare
geomagnetic disturbance

Opis:

Varying forms of solar radio burst were classified by their frequent changes in time, which are known as drift rate. There are 5 types of radio emission were named type I, II, III, IV and V. This paper is highlighted on the type III event which occurred on 27th August 2015. In the IP medium, type III solar radio burst can be classified in three different groups which representing three different situations of electron beam production and propagation which are isolated, complex and storm type III burst. The most powerful manifestation of solar activity is solar flare together with coronal mass ejections, eruptive prominences and the solar wind are the solar events which affect the earth's atmosphere and can cause geomagnetic disturbance. In this study, the effect of M class flare with solar radio burst type III was investigated. During the day, the solar wind proton density seems to be high which is 8.4 protons/cm3 and accompanied by normal solar wind speed of 348.7 km/Sec. Spaceweather.com reported that there is one sunspot was detected (AR2403) and M class of the flare was detected during the day at 0544 UT. The data geomagnetic signal shows that during the day only geomagnetic disturbance that occur no such geomagnetic storm since the sunspot not facing the earth directly.

Źródło:

World Scientific News; 2016, 44; 155-167
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 7.

Tytuł:

Experimental Study of Automatic Weapon Vibrations when Burst Firing

Autorzy:

Vo, Van Bien
Macko, Martin
Dao, Hung M.

Powiązania:

https://bibliotekanauki.pl/articles/2036918.pdf

Data publikacji:

2021

Wydawca:

Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego

Tematy:

vibration
weapon system
burst firing
firing stability
tripod

Opis:

The article presents a new approach to finding the dynamic characteristics of automatic weapons, mainly in case of burst firing. The experiments were tested out on a 30 mm AGS-17 grenade launcher mounted on a tripod in the event of a shot. The obtained results are the basis for evaluating the firing stability of an automatic weapon when burst firing, which allows modernising the existing weapons and evaluating similar weapon systems. Furthermore, the outputs can be used to validate a dynamic model of an automatic weapon system mounted on the tripod. The procedure can be used as an example of practical technique and methodology for other weapon systems.

Źródło:

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa; 2021, 12, 4 (46); 9-28
2081-5891

Pojawia się w:

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 8.

Tytuł:

Hydraulic fracturing technology in rock burst hazard controlling

Autorzy:

Karkocha, W.

Powiązania:

https://bibliotekanauki.pl/articles/89022.pdf

Data publikacji:

2015

Wydawca:

Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa

Tematy:

underground mining
rock burst
crump prevention
hydraulic fracturing

Opis:

All methods of rock burst hazard evaluation and control are classified as rock burst prevention. The prevention methods can be divided in two general categories – the passive (non-active) and active ones. Active methods of rock burst prevention focus generally on reducing of stress level in the area of its concentration through controlled tremors and rock bursts by blasting works. Among the active methods the hydraulic fracturing can be noted. Traditional hydraulic fracturing techniques generally form main hydraulic cracks. However, when we combine hydraulic fracturing with blasting we might obtain much better results. For example, the hydraulic crack range becomes wider than by using only conventional methods. In coal seams it is possible to increase permeability which makes gas drainage to be more effective. It is because water shockwaves and bubble pulsations induced by the explosion, cause a high strain rate in the rock mass surrounding the bore hole. When hydraulic fracturing is used, a micro seismic event takes place. This is why micro seismic technologies are used to monitor the range of hydraulic fracturing process. This article is only mentioning the issue which in the Author opinion, deserves more attention.

Źródło:

Mining Science; 2015, 22, Special Issue 2; 15-21
2300-9586
2353-5423

Pojawia się w:

Mining Science

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 9.

Tytuł:

Studies on the performance of impact resistant structure of hydraulic support in fully mechanized mining face under rock burst

Autorzy:

Zhang, Qiang
Zhang, Runxin

Powiązania:

https://bibliotekanauki.pl/articles/2200835.pdf

Data publikacji:

2022

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

rock burst
energy absorbing structures
finite element
mechanical properties

Opis:

In order to solve the support problem of a fully mechanized coal face under rock burst and with the goal of safe and efficient coal mining, the present study hasenvisaged a hexagon periodic arrangement energy absorption structure. Based on the shell theory, the mechanical model of the impact resistant structure and hydraulic support was constructed using the finite element method. The mechanical properties of the hydraulic support under a full impact and a partial load impact of the roof were analysed, and the impact resistant structure was designed to prove the reliability of the structure. The results showed that the anti-impact structure reduced the stress and stress fluctuation of the column and effectively reduced the shape variable of the weak link of the hydraulic support. Furthermore, a delay in the time was observed, when the pressure of the hydraulic cylinder reached the yield strength, and there was a gain in the time for the opening of the large flow safety valve. Especially, under the action of partial load, the column did not bend, and the hydraulic cylinder was in the elastic range. Our results can provide new insights in the support of rock burst working face, which is of great significance concerning safety in the coal mining.

Źródło:

Journal of Theoretical and Applied Mechanics; 2022, 60, 4; 649--658
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 10.

Tytuł:

New criteria to assess seismic and rock burst hazard in coal mines
Nowe kryteria dla oceny zagrożenia sejsmicznego i tąpaniami w kopalniach węgla kamiennego

Autorzy:

Mutke, G.
Dubiński, J.
Lurka, A.

Powiązania:

https://bibliotekanauki.pl/articles/220308.pdf

Data publikacji:

2015

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

mining seismology
rock burst
seismic event
seismic criterion
rock burst hazard assessment
sejsmologia górnicza
tąpnięcie
wstrząs sejsmiczny
kryterium sejsmiczne
ocean zagrożenia tąpnięciem

Opis:

The paper presents new criteria of seismic and rock burst hazard assessment in Polish hard coal mines where longwall mining system is common practice. The presented criteria are based on the results of continuous recording of seismic events and analysis of selected seismological parameters: spatial location of seismic event in relation to mining workings, seismic energy, seismic energy release per unit coal face advance, b-value of Gutenberg-Richter law, seismic energy index EI, seismic moment M0, weighted value of peak particle velocity PPVW. These parameters are determined in a moving daily time windows or time windows with fixed number of seismic tremors. Time changes of these parameters are then compared with mean value estimated in the analyzed area. This is the basis to indicate the zones of high seismic and rock burst hazard in specific moment in time during mining process. Additionally, the zones of high seismic and rock burst hazard are determined by utilization of passive seismic tomography method. All the calculated seismic parameters in moving time windows are used to quantify seismic and rock burst hazard by four level scales. In practice, assessment of seismic and rock burst hazard is used to make daily decision about using rock burst prevention activities and correction of further exploitation of monitored coal panel.
Zagrożenie sejsmiczne i związane z nim genetycznie zagrożenie tąpnięciem w dalszym ciągu należą do najgroźniejszych zagrożeń naturalnych występujących w polskich kopalniach węgla kamiennego. W ostatnich latach w kopalniach Górnośląskiego Zagłębia Węglowego (GZW) rocznie rejestrowano 1000÷1500 wstrząsów o energii sejsmicznej Es ≥ 1•105J (magnituda lokalna ML ≥ 1.7), a najsilniejsze z nich osiągały energię Es = 4 •109J (ML = 4.1). W latach 1991-2010 odnotowano w GZW 101 tąpnięć, z których około 66% miało miejsce w wyrobiskach chodnikowych, powodując ich uszkodzenia lub całkowite zniszczenie, a w niektórych przypadkach również wypadki śmiertelne. Przedstawiono podstawowe parametry sejsmologiczne stosowane w kraju i w świecie do oceny zagrożenia sejsmicznego. Opisano podstawowe zasady metody kompleksowej oceny stanu zagrożenia tąpnięciem, w skład której wchodzi metoda sejsmologiczna bieżącej (pomiarowej) oceny stanu zagrożenia. Od wielu lat, wraz z ciągłym rozwojem bazy aparaturowej i możliwości w zakresie cyfrowej rejestracji sejsmogramów oraz przetwarzania i interpretacji danych pomiarowych wzrasta znaczenie metod sejsmicznych, które są dzisiaj powszechnie stosowane w polskich kopalniach zagrożonych tąpaniami. Ciągła obserwacja zjawisk sejsmicznych indukowanych w trakcie rozwoju procesu eksploatacji pokładów węgla umożliwiła, w oparciu o zgromadzoną bazę danych, opracowywanie nowych kryteriów zagrożenia sejsmicznego oraz zagrożenia tąpnięciem, które winny wyraźnie poprawić efektywność metody sejsmologii górniczej. W artykule przedstawiono nowe kryteria oceny stanu bieżącego zagrożenia tąpaniami zaproponowane do stosowania w polskich kopalniach węgla kamiennego, które prowadzą eksploatację systemem ścianowym. Kryteria te są oparte na wynikach ciągłej rejestracji sejsmologicznej, połączonej z bieżącą analizą zarejestrowanych wstrząsów i obliczaniem wybranych parametrów sejsmologicznych. Parametry te to położenie ognisk wstrząsów w stosunku do wyrobisk eksploatacyjnych, energia sejsmiczna wstrząsów, suma energii sejsmicznej wyzwolona na każde 5m postępu ściany eksploatacyjnej, wartość wagowanego parametru amplitudy prędkości drgań PPVW, moment sejsmiczny M0, indeks energii EI oraz parametr b rozkładu wstrząsów według relacji Gutenberga-Richtera. Wartości powyższych parametrów są określane dla każdej doby lub w przesuwających się co dobę oknach czasowych lub oknach zawierających określoną liczbę wstrząsów, a następnie porównywane, raz na dobę, z ich wartościami średnimi wyznaczonymi dla obserwowanego rejonu eksploatacji lub z opracowanymi wartościami kryterialnymi. W ten sposób wyznaczane są, dla danego momentu czasu, strefy w których możne wystąpić potencjalnie wysokie zagrożenie sejsmiczne i zagrożenie tąpaniami. Ponadto, w strefach o podwyższonym naprężeniu oraz w strefach o skomplikowanej sytuacji górniczo-geologicznej, charakteryzujących się zaszłościami starej eksploatacji oraz zaburzeniami geologicznycmi, wykonywane są dodatkowo doraźne obliczenia pola prędkości fal sejsmicznych z wykorzystaniem metody tomografii pasywnej. Należy podkreślić, że wszystkie obliczane wartości powyższych parametrów są skwantyfikowane i określają wartości kryterialne w czterostopniowej skali oceny stanu zagrożenia sejsmicznego i zagrożenia tąpnięciem (tabela 2). Stopnie zagrożenia zostały skwantyfikowane w oparciu wyniki pomiarów sejsmologicznych wykonywanych na bieżąco w sposób ciągły i są wyrażone w formie kryteriów empirycznych, opracowanych na podstawie analizy dużego zbioru danych sejsmicznych oraz obserwacji makroskopowych w wyrobiskach górniczych. Należy podkreślić, że w czasie występowania wysokich stanów zagrożenia sejsmicznego lub zagrożenia tąpnięciem, opracowana metoda pozwala wyznaczyć obszary o podwyższonym stanie zagrożenia, umożliwiając zaprojektowanie i zastosowanie odpowiedniej w miejscu i czasie profilaktyki tąpaniowej. Ważnym aspektem w ocenie stanu zagrożenia sejsmicznego i tąpaniami jest problem ciągłego przemieszczania się stref zagrożenia (stref podwyższonych naprężeń) w czasie prowadzonej eksploatacji. Dla uchwycenia nie tylko miejsc potencjalnego zagrożenia, ale również określenia w jakim momencie czasu pojawia się strefa potencjalnego zagrożenia, zaproponowano analizę parametrów kryterialnych w przesuwających się oknach czasowych z dobowym raportowaniem wyników. W artykule przedstawiono dotychczasowe kryteria oceny stanu zagrożenia tąpnięciem – tabela 1 (Barański i in., 2007), stosowane aktualnie przez większość kopalń w polskim górnictwie węglowym. Kryteria te w części przypadków nie prowadziły do zadawalających i w pełni wiarygodnych wskazań, ze względu na małą liczbę analizowanych parametrów sejsmologicznych oraz brak sekwencyjnej analizy ich zmian w czasie prowadzonej eksploatacji. Wady te uwzględnia nowe podejście metodyczne do oceny stanu zagrożenia. Nowe kryteria oceny stanu zagrożenia sejsmicznego i zagrożenia tąpnięciem przedstawiono w tabeli 2. Zakwalifikowanie do określonego stanu zagrożenia wymaga spełnienia wartości kryterialnych przez więcej niż połowę parametrów sejsmicznych, przypisanych do określonego stanu zagrożenia i rodzaju wyrobiska. Skuteczność przedstawionych nowych kryteriów oceny stanu sejsmicznego i zagrożenia tąpnięciem, opartych o sekwencyjną analizę wybranych parametrów kryterialnych w przemieszczających się co dobę oknach czasowych, została pokazana na przykładach obliczeniowych rzeczywistych sytuacji pomiarowych uzyskanych podczas eksploatacji pokładu węgla 510 ścianą nr. 6 oraz pokładu 503 ścianą nr. 3 w KWK Bobrek-Centrum. Przeprowadzono dyskusję opracowanych kryteriów dowodząc, że stosowanie do oceny stanu zagrożenia tąpaniami różnych parametrów wstrząsów jest niezbędne, aby na bieżąco obserwować to zagrożenie w zależności od różnych mechanizmów wstrząsów i dla różnych sytuacji górniczo-geologicznych. Analiza jednego parametru kryterialnego może często doprowadzić do błędnych wniosków i niskiej wiarygodności wykonanej oceny stanu zagrożenia. Z tej przyczyny w najnowszej wersji metody sejsmologicznej zaproponowanej do stosowania w polskich kopalniach węgla kamiennego, uwzględniono pięć niezależnych parametrów sejsmologicznych opisanych w tabeli 2.

Źródło:

Archives of Mining Sciences; 2015, 60, 3; 743-760
0860-7001

Pojawia się w:

Archives of Mining Sciences

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 11.

Tytuł:

Type II Solar Radio Burst with a Split and Herring − Bones During a Minimum Solar Activity

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/411839.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
low frequency
solar radio
burst
type II
e-CALLISTO

Opis:

A preliminary correlation study of the herring − bone type II with a type III solar burst of has been made. On the basis of this study and in combination with the observation in radio emission, an interpretation of the mechanism of the occurrence of this event has been proposed. The type II solar radio burst with a split and herring bone is occurring at the same time from 36 MHz till 50 MHz. We have noted that an individual type III burst also can be observed at 13:23 UT from 45-50 MHz. During that day, a stream of solar wind from a coronal hole on the Sun has disturbing Earth's magnetosphere creating a minor geomagnetic storm, G1 on the NOAA scale of G1-G5. In this case, the solar flare is not very high, but CME is responsible to form a solar radio burst type II. Overall, based on seven days observation beginning from 25th March 2013, the solar activity is considered as very low. The highest solar flare can be observed within 7 days is only a class of B8 flare. There was no CMEs event that directed to the Earth is detected. The geomagnetic field activities are also at minimum level. Although the solar flare event is at a lower stage, it is still possible to form the solar radio burst type II which is associated with CME event. From the selected event, although theoretically solar radio burst type II is associated with CMEs, there is no compelling solar radio burst type II without a flare. The only difference is the dynamic structure and the intensity and speed of both phenomena (solar flares and CMEs) which depend on the active region. Nevertheless, understanding how energy is released in solar flares is one of the central questions in astrophysics. This solar radio burst type II formation is the first event that successfully detected by e-CALLISTO network in 2013.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 13, 2; 104-111
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 12.

Tytuł:

Nonlinear Behavior of the Radio Frequency Interference (RFI) Sources at Faculty of Applied Sciences, MARA University of Technology

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/412047.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Radio Frequency Interference (RFI)
RFI sources
solar radio burst
CALLISTO

Opis:

In this article, we describe and compare several sources of the nonlinear of Radio Frequency Interference (RFI) based on classification methods. It is very important to characterize and understand the nature of interference in as much of the candidate spectrum as possible. Preliminary analysis has been done in 2011. As data sizes of observations grow with new and improved solar monitoring system, the need for completely automated, robust methods for RFI mitigation is highlighted. The current status of RFI noise level is being compared at two different sites (i) indoor and (ii) outdoor. The main objective is to evaluate and find the best range of low frequency in MHz for the solar monitoring purpose. Our findings are consistent with those of previous studies. There is not much different in terms of the sources of RFI. However, the level of RFI is become increase. Based on the results, it was found that the distribution of RFI sources in indoor site is in the range from -(80-105) dBm. A strong and moderate RFI can be identified in the range of -100 dBm. The dominant sources in this region are due to the fixed mobile signal with 10 points of this signal from 1-2000 MHz. If we compare with outdoor site, the distribution of RFI sources in indoor site is in the range from -(75-105) dBm. It means that the signal of noise is larger compared with indoor site. While new sources strive to remain the increasing of RFI signal levels, numerous factors interact to influence the pattern of this noise. Reporting to the authoritative body should be made to make sure the allocation of the solar monitoring frequency region was not used by other applications. This work is a current scenario of the nonlinear RFI level at our site.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 15; 39-47
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 13.

Tytuł:

Statistical Study of Nine Months Distribution of Solar Flares

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/412246.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
solar eclipse
solar radio
burst
type III
e-CALLISTO

Opis:

Solar flare is one of the solar activities that take place in the outermost layer of the corona. Solar flares can heat the material to several million degrees in just a few minutes and at the same time they release the numerous amount of energy. It is believed that a change of magnetic field lines potentially creates the solar flares. The objectives of the study are to identify and compare the types of solar flares (in X-Ray) region and to improve understanding of solar flares. Data are taken from the NOAA website, from the United States Department of Commerce, NOAA, Space Weather Prediction Center (SPWC). Solar radio flux readings were merged together with the three classes and a total of nine graphs were plotted. In illustrating the relationship of solar radio flux and solar flares, it can be explained by studying the range values of flux corresponding to flares values. From this case study, it was found that the minimum value of solar radio flux in order for the flares to occur is equivalent 68 x 10^-22Wm^-2Hz^-1. Thus, whenever the values of solar radio flux are high, there should be a higher number of flares produced by the sun. The overall range of solar radio flux recorded in this study ranging from 68 x 10^-22 Wm^-2Hz^-1 to 96 x 10^-22 Wm^-2Hz^-1. Observing and collecting data from the Sun and develop our very own new prediction methods will leads the accuracy of the prediction of the behavior of the Sun more precisely.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 14, 1; 1-11
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 14.

Tytuł:

The Propagation of An Impulsive Coronal Mass Ejections (CMEs) due to the High Solar Flares and Moreton Waves

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/412288.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
solar eclipse
solar radio
burst
type III
e-CALLISTO

Opis:

This paper provides a short review of some of the basic concepts related to the origin of Coronal Mass Ejections (CMEs). The numerous ideas which have been put forward to elucidate the initiation of CMEs are categorized in terms of whether this event is a gradual CME or impulsive CME. In this case, an earth-directed Coronal Mass Ejection (CME) was observed on April 2, 2014 by the Large Angle Spectrometric Coronagraph (LASCO) C2. This recent observations obtained a large impulsive CMEs. The CME, originating from the active region AR2027. The speed of CMEs is 1600 kms^-1. A halo CME, a bright expanding ring at the North-West region is exploded beginning at about 14:36 UT, and the process of departing, expansion and propagation are highlighted. We discuss the correspondence of this event with the structure of the CME in the LASCO data. It is believed that the high solar flare and a Moreton waves initiate this kind of CMEs.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 14, 1; 118-126
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 15.

Tytuł:

Chronology of Formation of Solar Radio Burst Types III and V Associated with Solar Flare Phenomenon on 19th September 2011

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/411656.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

solar radio burst
solar flare
type III
type V
CALLISTO

Opis:

The formation of two different solar bursts, type III and V in one solar flare event is presented. Both bursts are found on 19th September 2011 associated with C-class flares on active region 1295. From the observation, we believed that the mechanism of evolution the bursts play an important role in the event. It is found that type V burst appeared in five minutes after type III. There are a few active regions on the solar disk but most are magnetically simple and have remained rather quiet. An interpretation of this new result depends critically on the number of sunspots and the role of active region 1295. Sunspot number is increased up to 144 with seven sunspots can be observed. During that event, the speed of solar wind exceeds 433.8 km/second with 2.0 g/cm3 density of protons in the solar corona. Currently, radio flux is also high up to 150 SFU. The solar flare type C6 is continuously being observed in the X-ray region for 24 hours since 1541 UT and a maximum C1 is detected on 1847 UT. Although the sources of both bursts are same, the direction and ejection explode differ.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 5; 32-42
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 16.

Tytuł:

Scenario of Solar Radio Burst Type III During Solar Eclipse on 14th November 2012

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/411752.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
solar eclipse
solar radio
burst
type III
e-CALLISTO

Opis:

A compact solar flare was observed during a total solar eclipse event on 13-14 November 2012. This phenomenon is beginning in local time on November 14 west of the date line over northern Australia, and ended in local time on November 13 east of the date line near the west coast of South America. During the eclipse, the highest magnitude was 1.0500, occurring only 12 hours before perigee, with the maximum eclipse totality lasting just over four minutes. Considering the observational facts, the solar radio burst type III can be detected from the National Space Centre Malaysia by the Compound Low Cost Low Frequency Transportable Observatory (CALLISTO) system from 00:00 UT –1:30 UT. The group and individual solar burst type III can be detected in the region of 150-400 MHz. However, the eclipse cannot be observed from our site. From the observation, it was found that the eruption in the active region is becoming more active with a tens of groups solar radio burst type III can be observed. It continuing bursting within the first one hour. The sunspot number exceeds to 108 and solar wind speed 454.9 km/sec. Still the Sun remains active and we need to consider other processes to explain in detailed the injection, energy loss and the mechanism of the acceleration of the particles.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 13, 2; 135-143
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 17.

Tytuł:

The Different Between the Temperature of the Solar Burst at the Feed Point of the Log Periodic Dipole Antenna (LPDA) and the CALLISTO Spectrometer

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/411932.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

CALLISTO
Log Periodic Dipole Antenna
LPDA
temperature
solar radio burst

Opis:

The article attempts to analyze and compare the temperature of solar radio burst at the (i) feed point and antenna and (ii) at the receiver (CALLISTO spectrometer). The analysis is very important to evaluate the performance for a better observation of solar radio burst. We start our project by developing this antenna with 19 elements of different sizes covers from 45 − 870 MHz. We choose the National Space Agency (PAN), Sg. Lang, Banting, Selangor, Malaysia as our site seems this site has a very minimum of Radio Frequency Interference (RFI). The antenna, then connects to the low noise amplifier and the CALLISTO spectrometer as one complete system. Based on the results, it was found that the temperature of the at the feed point of the antenna and receiver is different up to 3.25 K. The average level burst level above background sky is about 0.41dB. It was found that the power of solar burst at the feed point of the antenna is equivalent to 2.6 x 10-18 W, but decreases to 2.3 x 10-18 W when detected by the CALLISTO spectrometer. These results show a better understanding of how does the system operate in terms of the process of analysis of the temperature of solar radio burst.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 11, 2; 167-176
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 18.

Tytuł:

Evaluation of Spectral Overview and Radio Frequency Interference (RFI) Sources at Four Different Sites in CALLISTO Network at the Narrow Band Solar Monitoring Region

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/412644.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

CALLISTO
Radio Frequency Interference (RFI)
RFI sources
solar radio burst

Opis:

Continuous observation of solar radio burst in CALLISTO network was started since 2002 with Blein Switzerland is the first site that launched the system. Since then, there are more than 35 sites around the world that monitor the Sun activity within 24 hours until 2014. However, there is an issue of Radio Frequency Interference (RFI) that need to be considered. This noise is a major obstacle when performing observation with CALLISTO system. We selected 4 sites as preliminary analysis to analyze in detailed at a specific frequency which is very important in solar burst monitoring. The selected sites are (i) Blein, Switzerland (ii) Mauritius (iii) KASI Korea and (iv) ANGKASA, Malaysia. The regime narrow band that we focused are from (i) 72 – 75 MHz (ii) band 145 – 153 MHz (iii) 240 – 250 MHz (iv) 320 – 330 MHz (v) 406 – 410 MHz. The results of the sources of the RFI also will be highlighted. This work is was part of a larger study which focuses on a specific region that can be used for detailed investigation of solar burst. This issue of Radio Frequency Interference (RFI) needs a dialogue and interactions between different actors and networks.It is hoped that the analysis will help the solar physicist to choose a better data.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 11, 2; 135-145
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 19.

Tytuł:

Variation of bud flushing in Larix decidua clones

Autorzy:

Sierota, Zbigniew
Ukalska, Joanna
Zagożdżon, Marcin
Damszel, Marta
Zawadzka, Anna
Bystrowski, Cezary

Powiązania:

https://bibliotekanauki.pl/articles/956999.pdf

Data publikacji:

2017

Wydawca:

Polska Akademia Nauk. Instytut Dendrologii PAN

Tematy:

european larch
seed orchard
bud burst
temperature
generalized linear model

Opis:

In situ assessments of bud flushing in European larch Larix decidua Mill. clones growing under natural conditions were conducted in the Łęgajny seed orchard, Warmia-Masuria Province, Poland. The 27 assessed clones (among a total of 332 trees) were derived from superior plus trees from six selected stands in north eastern Poland. The analyses were carried out on 15-year-old clones grown in two seed orchard sectors differing in soil moisture conditions (no. 3, a nearly flat surface with southern exposure and no. 5, a flat surface, slightly inclined toward the north and periodically flooded by nearby bog-springs). Apical and axillary bud flushing was assessed in March/April 2014, using a 6-stage scale. Significant differences in bud burst were observed among clones, bud types (apical or axillary), clone provenances and growing conditions in seed orchard sectors. Generally, axillary buds flushed earlier than apical buds. Clones growing in section no. 3 showed earlier bud flushing than in section no. 5. Daily mean temperature during the initial bud burst period (stages 0–3) had no significant effect on bud flushing in a number of clones, however the cumulative temperature in that period was strong correlated with bud flushing for particular clones and provenances which suggests susceptibility to spring frost. Local site conditions (i.e. different soil moisture contents and insolation levels between sectors) as well as decreased temperatures in the first period of bud development had strong effects on bud flushing in European larch clones.

Źródło:

Dendrobiology; 2017, 77; 91-103
1641-1307

Pojawia się w:

Dendrobiology

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 20.

Tytuł:

The influence of normal fault on initial state of stress in rock mass

Autorzy:

Tajduś, A.
Cała, M.
Tajduś, K.

Powiązania:

https://bibliotekanauki.pl/articles/178408.pdf

Data publikacji:

2016

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

underground mining
stress field
tectonic disturbances
fault
rock burst
seismic events

Opis:

Determination of original state of stress in rock mass is a very difficult task for rock mechanics. Yet, original state of stress in rock mass has fundamental influence on secondary state of stress, which occurs in the vicinity of mining headings. This, in turn, is the cause of the occurrence of a number of mining hazards, i.e., seismic events, rock bursts, gas and rock outbursts, falls of roof. From experience, it is known that original state of stress depends a lot on tectonic disturbances, i.e., faults and folds. In the area of faults, a great number of seismic events occur, often of high energies. These seismic events, in many cases, are the cause of rock bursts and damage to the constructions located inside the rock mass and on the surface of the ground. To estimate the influence of fault existence on the disturbance of original state of stress in rock mass, numerical calculations were done by means of Finite Element Method. In the calculations, it was tried to determine the influence of different factors on state of stress, which occurs in the vicinity of a normal fault, i.e., the influence of normal fault inclination, deformability of rock mass, values of friction coefficient on the fault contact. Critical value of friction coefficient was also determined, when mutual dislocation of rock mass part separated by a fault is impossible. The obtained results enabled formulation of a number of conclusions, which are important in the context of seismic events and rock bursts in the area of faults.

Źródło:

Studia Geotechnica et Mechanica; 2016, 38, 1; 109-120
0137-6365
2083-831X

Pojawia się w:

Studia Geotechnica et Mechanica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 21.

Tytuł:

Correlation between Radio Flux (10.7 cm) and Sunspot Number Based on Statistical Properties

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/1189949.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Sun
solar burst
radio region
solar flare
Coronal Mass Ejections (CMEs)

Opis:

Statistical properties of solar radio burst radio type II and III of this work will be highlighted. One of the best advantages of using the radio method is that it allows high quality images within an arc second resolution and different frequencies actually cover different layers of the solar atmosphere. Statistical studies of both bursts are required to obtain such observational constraints with sufficient statistical confidence. In the first part, the trend of both bursts from 2006-2011 is examined. We need to consider a few parameters such as a burst duration, drift rate, energy of the photon, and the structure of the burst. From (0.0 0.5) MHz/Sec, the data represent the highest slope with m = 1290.1685 km/MHz in average. In the range of (4.0 7.0) MHz/Sec, the range of CMEs velocity is less than 500km/Sec. The lowest CMEs velocity that can be observed is ~137 km/Sec. The relationship between both parameters is F10.7cm = 0.4568R + 73.8655. This work presents the first step toward an analytical model of statistics of solar radio burst information of average events as something crucial to the acceleration mechanism.

Źródło:

World Scientific News; 2016, 52; 70-80
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 22.

Tytuł:

Comparison of the Optical Image of the Solar Prominence with the Formation of Solar Radio Burst Type III on 3rd September 2015

Autorzy:

Hamidi, Z. S.
Norsham, N. A.
Mazlan, Muzamir
Yusof, N. S.
Jafni, A. I.
Kahlid, N. M.
Hamdan, M. N.
Kamaruddin, Farahana
Tahar, Muhammad Redzuan
Monstein, C.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/1192670.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

solar prominences
solar radio burst
type III
AR2407
e CALLISTO

Opis:

Solar radio burst in the range of 220 - 400 MHz have been correlated with the optical solar prominence phenomena covering the presence sunspot minimum. In combination of the observation in radio emission and the basis of this study, the occurrence of the event has been proposed. The active region of the prominence was AR2407. An individual type III burst was observed at 08:21 UT. The burst lasts for 20 seconds with a drift rate of 4.25 MHz/s. This burst was recorded by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) at Switzerland. The CALLISTO spectrometer is a spectrometer system that has been installed all around the world to observe the activity of the sun for 24 hours. The activation may be caused by shock waves issuing from prominences and solar flares. The loop prominences can be observed by using the optical telescope and is the initiates points of the following important flare that exist for 6 hours. The active region on the Sun experience the gradual build up of the magnetic field which gives rise to the sunspots, prominences and loops in the corona and produce the powerful outburst explosions.

Źródło:

World Scientific News; 2016, 47, 2; 230-240
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 23.

Tytuł:

Emergence of an Impulsive CMEs Related To Solar Radio Burst Type III Due To Magnetic Filament Eruption

Autorzy:

Ali, M. Omar
Shariff, N. N. M.
Hamidi, Z. S.
Husien, Nurul Hazwani
Sabri, S. N. U.
Zainol, N. H.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/1192085.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Sun
Coronal Mass Ejections (CMEs)
solar burst type III
magnetic filament

Opis:

During solar activity the energy particles of the sun released due to solar flare, Coronal Mass Ejections (CMEs), coronal heating as well as sunspot. Solar radio burst will be observed in the presence of solar activity such solar flare, CMEs and solar prominence as the indicator for those events to happen. During the peak of solar cycle, the filaments are present due to the active magnetic field and solar storm’s explosion. This type of solar radio burst normally can be seen in the phase of impulsive solar flare. Therefore, it is crucial to understand field line connectivity in flare and the access of flare accelerated particle to the earth. In this study, we highlighted on the observation of solar radio burst type III on 9th of May at 05:31 UT till 05:44 UT. The event was successfully recoded by e-CALLISTO using BLEINSW radio telescope. The Solar Radio Burst Type III that had been observed was related to the Coronal Mass Ejections and the mechanisms that trigger the events have been discussed. It is shown that the CMEs is believed to happen because of the magnetic filament that connected to active region (AR) 2339 was erupted, and combination of two wild filament produced a bright CMEs. Fortunately, the expanding cloud does not appear to be heading for earth.

Źródło:

World Scientific News; 2016, 37; 168-178
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 24.

Tytuł:

An Analysis of Active Regions 11036 Characteristics Leads To Solar Flare Class C7.2 Phenomena

Autorzy:

Zainol, N. H.
Hamidi, Z. S.
Husien, Nurulhazwani
Ali, M. O.
Sabri, S. N. U.
Shariff, N. N. M.
Faid, M. S.
Monstein, C.
Ramli, Nabilah

Powiązania:

https://bibliotekanauki.pl/articles/1192106.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Solar Radio Burst Type II
solar flare
Callisto network
active region

Opis:

The solar flares are generated from electromagnetic radiation which is sudden oscillation of the stored energy in the magnetic field of the sun. Flares are categorized according to their brightness as C, M and X, where X is the brightest. The X class flares caused a long-time solar storm and ionospheric radio waves sparkling. The moderate level M class flares mostly effect polar cups and cause short-time radio sparkling. However, the C class flares are weaker than the X and M flares. In this work, we present an active region from the disturbance of magnetic field on the area of the Sun and may lead to powerful event if the magnetic field become stronger. The CALLISTO system network that has been installed in Gauri, India observed data that contain Solar Radio Burst Type II (SRBT II) occurred on 22nd December 2009 at 04:57 UT to 05:02 UT. Five active regions were obtained from online data via internet from the Space Weather website and the Solar Monitor website. All data and information from these sources assist in analyze of the phenomena. The magnetic field and X-ray flux, proton density increase the possibilities that SRBT II observed by CALLISTO network to generate powerful solar flare. When X-ray flux level was at maximum, then solar flare was at peak point. However, solar activity level was low because among of five active regions present, only one C-class flare event occurred. The most active region that contributes this event is an AR11036 with C-class flare.

Źródło:

World Scientific News; 2016, 45, 2; 80-91
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 25.

Tytuł:

The method of assessing rock bursting hazard in mining
Metoda oceny stanu zagrożenia tąpaniami w kopalniach węgla kamiennego

Autorzy:

Manowska, A.

Powiązania:

https://bibliotekanauki.pl/articles/1206307.pdf

Data publikacji:

2015

Wydawca:

STE GROUP

Tematy:

rock burst hazard
work organization methods
zagrożenie tąpaniami
metody organizowania pracy

Opis:

The article discusses a concept of forecasting accident risk during longwall extraction in crump-risk conditions. In Polish mines rock burst hazard can be described as high compared to other mines around the world. It's related to increase of depth of longwall field operation, preparation works, including drilling of mine face pavements which leads to systematic deterioration of geological and mining conditions. Depletion of coal is also the reason why mines operate in high mining tremor risk conditions. Mines more and more often operate in decks, where there is large number of edges and remains of older decks. Rocks bursts still remain one of the most dangerous natural hazards and therefore are fundamental problem and have the greatest impact on safety in mining industry. The proposed method for forecasting accidents and losses in people and goods can contribute to improvement of work organization methods and mine safety management system.
W artykule zaprezentowano koncepcję przewidywania ryzyka wypadkowego w czasie prowadzenia eksploatacji ścianowej, w warunkach zagrożenia tąpnięciem. W polskich kopalniach zagrożenia tąpaniami można określić jako duże. Wynika to ze wzrostu głębokości eksploatowanych pól ścianowych i robót przygotowawczych, w tym drążenia przodków chodnikowych, co systematyczne pogarsza warunki geologiczno-górnicze. Wyczerpywanie się zasobów węgla to również powód prowadzenia eksploatacji w warunkach zagrożenia wstrząsami górniczymi. Kopalnie coraz częściej podejmują eksploatację pokładów, gdzie występuje duża liczba krawędzi i resztek pokładów. Tąpania należą ciągle do najbardziej niebezpiecznych zagrożeń naturalnych, są więc zasadniczym problemem i mają największy wpływ na bezpieczeństwo pracy w górnictwie. Zaproponowany sposób przewidywania możliwości wystąpienia tąpnięcia i wielkości strat ludzkich oraz strat rzeczowych może wpłynąć na doskonalenie metod organizowania pracy, a także na usprawnianie systemu zarządzania bezpieczeństwem kopalni.

Źródło:

Management Systems in Production Engineering; 2015, 2 (18); 88-93
2299-0461

Pojawia się w:

Management Systems in Production Engineering

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 26.

Tytuł:

Fundamental and Second Harmonic Bands of Solar Radio Burst Type II Caused by X1.8 - Class Solar Flares

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/411652.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

solar physics
radio burst
type II
Zeeman Effect
solar flare
CALLISTO

Opis:

An extreme 2012 October 23 solar flare event marked on the onset of the CALLISTO data, being one of the highest solar flare event that successfully detected. The formation of harmonic solar burst type II in meter region and their associated with X1.8-class solar flares has been reported. This burst has been observed at the National Space Centre, Banting, detected by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) system in the range of 150-400 MHz in the low frequency band. It occurred between 3.17:45 UT to 3.19:00 UT within 1 minute 15 seconds. The Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory CALLISTO spectrometer is a solar dedicated spectrometer system that has been installed all over the world to monitor the Sun activity in 24 hours. The growth of this burst is often accompanied by abundance enhancement of particles which may take the form of multiple independent drifting bands or other forms of fine structure. Due to the results, the drift rate of this burst is 2.116 MHz s–1, which is considered as a slow drift rate. These drifting bands are approximately having a frequency ratio 2:1. This burst is a particular interest, though of sporadic and infrequent occurrence. The splitting is due to the effect of magnetic splitting, analogous to the Zeeman Effect. This is one of the examples which the type II burst is not always associated with CMEs event. The combination of radio and x-ray region give a complete view of the solar flare eruption from e active region AR1598. Both different electromagnetic spectrum shows the exact time. Other interesting results is that this type II burst is not associated with CMEs as usual, but due to the very high solar flare event with a fundamental form at more than 100 MHz. An extension of the present work will be a detailed study of the possible triggering and the driving mechanism of solar flare explosion.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 14, 2; 208-217
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 27.

Tytuł:

Comparison of the Radio Frequency Interference (RFI) in the Region of Solar Burst Type III Data At Selected CALLISTO Network

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/412319.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

CALLISTO
low frequency
solar burst type III
Radio Frequency Interference (RFI)

Opis:

Compact Astronomical Low-frequency, Low-cost Instrument for Spectroscopy in Transportable Observatories (CALLISTO) is a global network of spectrometer system with the purpose to observe the Sun’s activities. There are 25 stations that are used for this purpose. Radio Frequency Interference (RFI) is a major obstacle when performing observation with CALLISTO. We have confirmed at least 2 stations out of 10 stations with a complete overview spectral (OVS) made available to us showed clear detection of these consistent types of RFI for each specific region. In Malaysia, these RFI are also clearly detected. The major RFI affecting CALLISTO within radio astronomical windows below 1 GHz are local electronic system specifically radio navigation (at 73.1 MHz and 75.2 MHz), broadcasting (at (i) 151 MHz, (ii) 151.8 MHz and 152 MHz), aeronautical navigation (at (i) 245.5 MHz, (ii) 248.7 MHz and (iii) 249 MHz and fixed mobile at (i) 605 MHz, (ii) 608.3 MHz, (iii) 612.2 MHz, (iv) 613.3 MHz). It is obviously showed that all sites within this region are free from interference at 320-330 MHz and is the best specific region to be considered for solar burst monitoring. We also investigate the effect of RFI on detection of solar burst. We have considered type III solar bursts on 9th March 2012 in order to measure the percentage of RFI level during the solar burst. The RFI level is as low as 6.512 % to 80.769 % above solar burst detection.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 10; 38-45
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 28.

Tytuł:

Zagrożenia tąpaniami w polskim górnictwie w latach 1980-2015
The rock burst hazard in Polish mining industry between 1980 and 2015

Autorzy:

Rawicki, Z.
Stępień, A.
Rożek, E.
Błaszczyk, A.

Powiązania:

https://bibliotekanauki.pl/articles/167329.pdf

Data publikacji:

2016

Wydawca:

Stowarzyszenie Inżynierów i Techników Górnictwa

Tematy:

tąpania
wstrząs
profilaktyka
nadzór górniczy
rock burst
tremor
prevention
mining supervision

Opis:

Zagrożenie tąpaniami należy od wielu lat do najniebezpieczniejszych zagrożeń naturalnych, występujących w polskim górnictwie. Wielkość tego zagrożenia uzależniona jest od warunków prowadzenia działalności górniczej - zarówno naturalnych, jak głębokość zalegania złoża czy występowanie zaburzeń geologicznych, a także górniczych - wynikających z dokonanej wcześniej eksploatacji, zastosowanej technologii lub koordynacji robót. W latach 2014-2015 zagrożenie tąpaniami występowało w 22 z 30 czynnych kopalń węgla kamiennego oraz we wszystkich trzech kopalniach rud miedzi, a wspomnieć należy również o aktywności sejsmicznej generowanej odkrywkową eksploatacją węgla brunatnego. O tym, że jest to nadal zagrożenie realne, świadczy występowanie w latach 2013 - 2015 tąpnięć, w wyniku których pracownicy zatrudnieni pod ziemią ulegli wypadkom, w tym śmiertelnym. W artykule przedstawiono dane statystyczne dotyczące rejestrowanych w latach 1980-2015 wysokoenergetycznych zjawisk sejsmicznych, zaistniałych tąpnięć oraz towarzyszących im wypadków, w korespondencji z uzyskanym wydobyciem. Omówiono wykorzystywane w podziemnych zakładach górniczych metody oceny stanu zagrożenia tąpaniami, jak również stosowane środki profilaktyki aktywnej i pasywnej, obejmującej już fazę projektowania eksploatacji górniczej lub poprzez działania organizacyjne stosowane w fazie prowadzenia eksploatacji. Integralną część artykułu stanowi opis niektórych działań organów nadzoru górniczego w celu ograniczenia zagrożenia tąpaniami w zakładach górniczych. Przedstawiono wnioski zespołu doradczo-opiniodawczego powołanego przez Prezesa Wyższego Urzędu Górniczego do analizy niektórych zagadnień związanych ze wstrząsem o energii 4x109 J i tąpnięciem, zaistniałym w dniu 18 kwietnia 2015 r. w KHW S.A. KWK „Wujek" w Katowicach Ruch „Śląsk". We wnioskach artykułu przedstawiono podstawowe kierunki działań zmierzających do dalszej poprawy w zakresie rozpoznania i zwalczania zagrożenia tąpaniami w przyszłości.
For many years rock burst hazard has been among the most dangerous natural hazards encountered in Polish mining industry. This hazard's size depends on the conditions in which mining operations take place - may they be natural, like the deposit's depth or existing geological fault, or mining-related - resulting from previous extraction, technology used or the coordination of works. In 2014 rock burst hazard occurred in 22 out of 30 active hard coal mines and in all three copper ore mines. The fact that this is still a real threat is evidenced by the rock bursts that occurred between 2013 and 2015 and resulted in accidents, including fatal ones among underground workers. This paper presents statistical data of high-energy seismic tremors, rock bursts and accidents accompanying them in relation to the level of extraction recorded between 1980 and 2015. It discusses the methods for assessing rock burst hazard used in underground mines as well as active and passive preventive measures applied either in the design phase of mining operations, or used as organizational actions in the extraction phase. An integral part of the paper is the description of some of the mining supervision authorities' actions that have been taken in order to reduce the risk of rock burst hazard in mines. Furthermore, it presents the conclusions of the advisory-consultative panel appointed by the President of the State Mining Authority to examine certain issues related to the high-energy tremor of 4x109 J magnitude and the rock burst which occurred on 18 April 2015 in KHW SA „Wujek" hard coal mine in Katowice. This paper concludes with the description of the basic lines of action to be taken for further improvement of the identification of and prevention from rock burst hazard in the future.

Źródło:

Przegląd Górniczy; 2016, 72, 4; 38-47
0033-216X

Pojawia się w:

Przegląd Górniczy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 29.

Tytuł:

Method of Testing of Sound Absorption Properties of Materials Intended for Ultrasonic Noise Protection

Autorzy:

Pleban, D.

Powiązania:

https://bibliotekanauki.pl/articles/177443.pdf

Data publikacji:

2013

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

ultrasonic noise
sound absorption coefficient
tone burst technique
sound absorbing material

Opis:

Efficient ultrasonic noise reduction by using enclosures requires the knowledge of absorbing properties of materials in the frequency range above 4 kHz. However, standardized methods enable determination of absorption coefficients of materials in the frequency range up to 4 kHz. For this reason, it is proposed to carry out measurements of the sound absorption properties of materials in the free field by means of a tone-burst technique in the frequency range from 4 kHz to 40 kHz at angles of incidence varying from 0° to 60°. The absorption coefficient of a material is calculated from the reflection coefficient obtained by reflecting a tone-burst from both a perfectly reflecting panel and a combination of this panel and the sample of the tested material. The tests results show that mineral wool and polyurethane open-cell foam possess very good absorbing properties in this frequency range.

Źródło:

Archives of Acoustics; 2013, 38, 2; 191-195
0137-5075

Pojawia się w:

Archives of Acoustics

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 30.

Tytuł:

First Light Detection of A Single Solar Radio Burst Type III Due To Solar Flare Event

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/411677.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Solar flare
low frequency
radio wavelength
solar burst
type III
CALLISTO

Opis:

The eruption mechanism of solar flares and type III are currently an extremely active area of research, especially during the solar cycle is towards maximum. In this case, the total energy of solar burst type III is of the order of solar flare with the explosion of the energy can up to 1015 ergs. The solar flare event is one of the most spectacular explosions that still be on-going study in the solar physics world. This event occurred at 2:000 UT on 15th April 2012 is due to the explosion of the magnetic energy in from the chromosphere and converted into the heating, mass motion and particle acceleration which can be detected by solar radio burst type III. In this work, we will highlight our first light detection of very tiny solar radio burst type III, which has been observed at the National Space Centre, Banting, Selangor detected by the Compound Low Cost Low Frequency Transportable Observatories (CALLISTO) system at 5:53:23. The region of the data is from 150 − 400 MHz in radio region. This burst is drifted from 150 MHz till 260 MHz. It represents a total energy of 6.2035 × 10-7 eV − 1.0753 × 10-6 eV. This fast drift burst is a continuity of the acceleration of the particles which is intermittent, and can be observed since the explosion of the solar flare. Although the burst is very tiny, it is still significant because this burst is the first detection of a single type III burst from our site. Still, the acceleration of the particles can be detected from Earth in the radio region within 3 hours period of observation at the post stage of solar flare.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 11, 1; 51-58
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 31.

Tytuł:

An Observation of an Inverted Type U Solar Burst Due to AR1429 Active Region

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/412209.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

CALLISTO
low frequency
solar burst
type U
Radio Frequency Interference (RFI)

Opis:

A detailed investigation of an inverted type U solar burst in meter region and their associated the solar flare and Coronal Mass Ejections (CMEs) has been reported. Solar type U burst has been observed at the National Space Centre, Banting, Selangor detected by the Compound Low Cost Low Frequency Transportable Observatories (CALLISTO) system in the 150 MHz till 400 MHz at the low frequency band. An inverted U type is occurring on 9th March 2012 between 4:00 UT to 4:15 UT within 1 minute (4:12 − 4:13) UT. From the dynamic spectra of CALLISTO, we have identified metric type U burst with maximum emission near the frequency 385MHz. In specific, the continuum type III burst will soon structure this burst due to our observations. Other types such as type II and IV are only appearing only after type U burst is ejected and appear at the same point of the solar flare event. Since the U burst activity coincides with the peak of the hard X-ray flare at 4:12UT in AR1429, we classified that the event is associated with the injection of the high energetic particles. In conclusion, it is confirmed that an inverted type U burst is initiated after a complex and a group solar radio burst type III.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 10; 81-90
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 32.

Tytuł:

The Progression of Active Region with the Formation of Group and Complex Solar Radio Burst Type III on 31st August 2015

Autorzy:

Hamidi, Z. S.
Norsham, N. A.
Mazlan, Muzamir
Yusof, N. S.
Jafni, A. I.
Kahlid, N. M.
Hamdan, M. N.
Kamaruddin, Farahana
Tahar, Muhammad Redzuan
Monstein, C.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/1182942.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

solar prominences
complex solar radio burst
type iii
ar2403
e callisto

Opis:

In this event, a solar radio burst in the range of 45-165 MHz with energy of 〖2.982 x 10〗^(-26) to 〖1.093 x 10〗^(-25) Joule with 0.8 MHz/ second have been correlated with the optical solar prominence. In combination of the optical, radio and X-ray observation, the occurrence of the event has been proposed. The active region of the prominence was AR2403. An individual type III burst was observed at 19:40 UT. The burst lasts for 15 minutes with a drift rate of 0.8 MHz/s. This burst was recorded by the Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) at Almaty Site. From 29th August 2015 onwards, the total magnetic flux increases gradually to over four-fold the initial value during development and levels off around 29th August 2015. It was found that B3 solar flare, followed by a slow coronal mass ejection (CME), is released from NOAA 2403 on 31st August 2015. The region is beyond -30 longitude at the time of the flare, making it impossible to reliably measure any magnetic properties involving gradients. The overall increase of Beff prior to the flare is indicative of an increase in polarity mixing within the AR, which has been shown to be related to flaring. Understanding of the exact nature of the initiation of these events is still incomplete.

Źródło:

World Scientific News; 2016, 49, 2; 272-282
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 33.

Tytuł:

Experimental Analysis of Horizontal Turbulence of Flow over Flat and Deformed Beds

Autorzy:

Termini, D.

Powiązania:

https://bibliotekanauki.pl/articles/241285.pdf

Data publikacji:

2015

Wydawca:

Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN

Tematy:

open-channel flow
flow turbulence structure
burst cycle
bed forms
laboratory experiments

Opis:

Laboratory experiments in a straight flume were carried out to examine the evolution of large-scale horizontal turbulent structures under flat-bed and deformed-bed conditions. In this paper, the horizontal turbulence of flow under these conditions is analyzed and compared. The conditioned quadrant method is applied to verify the occurrence of turbulent events. The distributions of horizontal Reynolds shear stress and turbulent kinetic energy are also presented and discussed. Results show the occurrence of an “initial” sequence of horizontal vortices whose average spatial length scales with the channel width. Under deformed-bed conditions, this spatial length does not change.

Źródło:

Archives of Hydro-Engineering and Environmental Mechanics; 2015, 62, 3-4; 77-99
1231-3726

Pojawia się w:

Archives of Hydro-Engineering and Environmental Mechanics

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 34.

Tytuł:

Observations of Different Type of Bursts Associated with M 6.3 Solar Flares

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/412558.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
low frequency
solar radio
burst
type III
type U
e-CALLISTO

Opis:

Variation of solar bursts due to solar flares such as type an isolated type III , a complex type III, U is being highlighted. These bursts occurred on 9th March 2012 at the National Space Centre, Sg. Lang, Selangor, Malaysia Here, we study a unique case with a combination of two types burst associated with solar flare and CMEs. Our observation is focused on the low frequency region starting from 150 MHz till 400 MHz. We found that a solar flare type solar flare type M 6.3 which occurred in active region AR 1429 starting from 3:32 UT and ending at 05:00 UT. The flare has been confirmed to be the largest flare since 2005. Some physical parameters will be measured. We then compared our results with X-ray data from NOAA Space Weather Prediction Centre (SWPC).

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 4; 29-36
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 35.

Tytuł:

The Tendencies and Timeline of the Solar Burst Type II Fragmented

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/412634.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
low frequency
solar radio
burst
type II
type III
e-CALLISTO

Opis:

We report the timeline of the solar radio burst Type II that formed but fragmented at certain point based on the eruption of the solar flare on 13th November 2012 at 2:04:20 UT. The active region AR 1613 is one of the most active region in 2012. It is well known that the magnetic energy in the solar corona is explosively released before converted into the thermal and kinetic energy in solar flares. In this work, the Compound Astronomical Low-frequency, Low-cost Instrument for Spectroscopy Transportable Observatories (CALLIISTO) system is used in obtaining a dynamic spectrum of solar radio burst data. There are eight active regions and this is the indicator that the Sun is currently active. Most the active regions radiate a Beta radiation. The active regions 1610, 1611 and 1614 are currently the largest sunspots on the visible solar disk. There is an increasing chance for an isolated M-Class solar flare event. It is also expected that there will be a chance of an M flare, especially from AR 1614 and 1610. Although these two observations (radio and X-rays) seem to be dominant on the observational analysis, we could not directly confirmed that this is the only possibility, and we need to consider other processes to explain in detailed the injection, energy loss and the mechanism of the acceleration of the particles. In conclusion, the percentage of energy of solar flare becomes more dominant rather than the acceleration of particles through the Coronal Mass Ejections (CMEs) and that will be the main reason why does the harmonic structure of type II burst is not formed. This event is one fine example of tendencies solar radio burst type III, which makes the harmonic structure of solar radio burst type II fragmented.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 12; 84-102
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 36.

Tytuł:

Double spinal cord stimulators (SCS) with different types of stimulation implanted percutaneously – case report and literature review
Zastosowanie podwójnych stymulatorów rdzenia kręgowego (SCS) o różnym typie stymulacji implantowanych metodą przezskórną – opis przypadku i przegląd literatury

Autorzy:

Ślusarczyk, Wojciech T.
Laskowski, Maciej
Kwiatkowska, Marta A.
Koperczak, Agnieszka

Powiązania:

https://bibliotekanauki.pl/articles/30147317.pdf

Data publikacji:

2024-04-29

Wydawca:

Śląski Uniwersytet Medyczny w Katowicach

Tematy:

low back pain
SCS
FBSS
spinal cord stimulation
failed back surgery syndrome
burst stimulation
bóle pleców
stymulacja rdzenia kręgowego
zespoły bólowe po nieskutecznych operacjach kręgo-słupa
stymulacja typu burst

Opis:

INTRODUCTION: Spinal cord stimulation (SCS) has emerged as a prevalent therapy for chronic neuropathic pain and failed back surgery syndrome (FBSS) over the past three decades, offering various stimulation types differentiated primarily by frequency. CASE REPORT: A 51-year-old male patient in 2016 underwent lumbar discectomy – L4/L5 due to symptomatic discopathy, which resulted in pain relief; however, the symptoms returned. In 2021 a Stimwave high-frequency (HF) SCS was placed epidurally at Th8–Th10. The patient reported substantial improvement after stimulation, nevertheless, after two weeks there was sudden exacerbation of his symptoms, especially in the lumbar region. Despite multiple attempts at program change and confirmation of the electrode location, there was no improvement. The HF stimulator was not removed owing to the risk of complications and 20% relief of pain in the right lower limb. After two years he was qualified for the implantation of newer generation of stimulators – BurstDR™ stimulation. An epidural electrode was implanted at Th8–Th10, followed by the placement of a BurstDR™ pulse generator. Currently, the patient has two active electrodes, one with HF stimulation, the other with BurstDR™ stimulation. CONCLUSIONS: Our case report demonstrates that there is no need to abandon SCS after the first failed attempt and it is worth trying stimulation with a different modulation. Furthermore, according to our center’s experience, the therapeutic effects of HF stimulation are quickly depleted and only after using burst stimulation was the expected result achieved. The reasons for this phenomenon are unknown and should be further researched.
WSTĘP: W ciągu ostatnich trzech dekad stymulacja rdzenia kręgowego (spinal cord stimulation – SCS) stała się powszechną metodą leczenia w przypadku przewlekłych neuropatycznych zespołów bólowych oraz problemów związanych z niepowodzeniem operacji kręgosłupa (failed back surgery syndrome – FBSS). Istnieje kilka rodzajów stymulacji, różniących się głównie częstotliwością prądu. OPIS PRZYPADKU: 51-letniego pacjenta operowano w 2016 r. z powodu dyskopatii na poziomie L4/L5. Po zabiegu nastąpiła poprawa, jednak dolegliwości wróciły. Po nieudanym leczeniu zachowawczym pacjent został zakwalifikowany do implantacji SCS. W 2021 r. założono stymulator SCS do stymulacji o wysokiej częstotliwości (high-frequency – HF) na poziomie Th8–Th10. Pacjent zgłaszał znaczną poprawę podczas stymulacji, jednak po dwóch tygodniach nastąpił nagły powrót dolegliwości bólowych. Wielokrotnie próbowano zmiany programu stymulacji, jednak bez wyraźnych rezultatów. Dodatkowo wykluczono migrację elektrody. Zdecydowano nie usuwać stymulacji typu HF, gdyż wiąże się to z ryzykiem powikłań. Po dwóch latach pacjent został zakwalifikowany do wszczepienia nowszej generacji stymulatorów – stymulacji BurstDR™. W miejscu Th8–Th10 wszczepiono elektrodę zewnątrzoponową, następnie umieszczono generator impulsów BurstDR™. Po zastosowaniu nowego typu stymulacji dolegliwości bólowe znacznie się zmniejszyły. Obecnie pacjent ma dwie elektrody aktywne, jedną ze stymulacją HF, drugą ze stymulacją BurstDR™. WNIOSKI: Opisany przypadek pokazuje, że nie należy rezygnować ze stymulacji rdzenia kręgowego przy pierwszym niepowodzeniu; warto podjąć próbę stymulacji w innej modulacji. Ponadto z doświadczeń naszego ośrodka wynika, że efekt terapeutyczny stymulacji typu HF szybko ulegał wyczerpaniu, a dopiero zastosowanie stymulacji BurstDR™ powodowało dużą poprawę w zmniejszeniu dolegliwości bólowych. Przyczyna tego zjawiska powinna stać się przedmiotem dalszych badań.

Źródło:

Annales Academiae Medicae Silesiensis; 2024, 78; 104-107
1734-025X

Pojawia się w:

Annales Academiae Medicae Silesiensis

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 37.

Tytuł:

Investigation on a Broken Solar Burst Type II during High Activities in AR1613 on 13th November 2012

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.
Monstein, C.
Zulkifli, W. N. A. W.
Ibrahim, M. B.
Arifin, N. S.
Amran, N. A.

Powiązania:

https://bibliotekanauki.pl/articles/411666.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
low frequency
solar radio
burst
type II
type III
e-CALLISTO

Opis:

The present article is an attempt to analyze the solar burst Type II observations based on solar flare and Coronal Mass Ejections (CMEs) events. We choose an intriguing type II radio burst with a velocity of 1193 kms-1 that occurred on 2012 November 13 at 2:04:20 UT. In this case, the study of solar radio burst type III is of paramount importance because of the fact that it helps to gain an insight of generation mechanisms of solar flare and Coronal Mass Ejections (CMEs) phenomena. Here, we have got a reasonably clear idea of the various forms under which the type III continuum emission may appear and potentially form a type II burst. However, in this case, the Type II solar burst only successfully forms a fundamental structure within the first few minute period, but broken suddenly before evolve a harmonic structure. This phenomenon is very interesting to be tackled and study. How the burst suddenly broken is still ongoing research seems the event is very rare and hard to be proved. There are a few questions that cause this unique situation which related to: (i) the intensity and duration of type III burst which also related to the classification of solar flare (ii) the probabilities CMEs to occur during that time and also the factor of the total amount of massive burst that exploded, Thus, we can conclude that the solar burst type III event still tells us an enigmatic characteristic from time to time due to the relationship of energetic particles and streams of particles with coronal magnetic fields and the pattern of Sun activity due to the 24th solar cycle. It might an interesting to study in detail the main factor that caused the Type II solar burst broken. Indirectly, it might because of the very intense of solar flares that make the percentage of energy of solar flare become more dominant rather than the acceleration of particles through the Coronal Mass Ejections. Thus, we realize that the potential energy during this event is higher than the kinetic energy of the particles.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 9; 8-15
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 38.

Tytuł:

The flavonoids, quercetin and isorhamnetin 3-O-acylglucosides diminish neutrophil oxidative metabolism and lipid peroxidation.

Autorzy:

Zielińska, Małgorzata
Kostrzewa, Artur
Ignatowicz, Ewa
Budzianowski, Jaromir

Powiązania:

https://bibliotekanauki.pl/articles/1044184.pdf

Data publikacji:

2001

Wydawca:

Polskie Towarzystwo Biochemiczne

Tematy:

flow cytometry
respiratory burst
polymorphonuclear neutrophils
reactive oxygen species
lipid peroxidation
flavonoids

Opis:

Two natural flavonoids, quercetin and isorhamnetin 3-O-acylglucosides, were examined for their inhibitory influence on the in vitro production and release of reactive oxygen species in polymorphonuclear neutrophils (PMNs). The generation of superoxide radical, hydrogen peroxide and hypochlorous acid were measured by, respectively, cytochrome c reduction, dichlorofluorescin oxidation and taurine chlorination. Membrane lipid oxidation was studied by the thiobarbituric acid method in mouse spleen microsomes. The addition of flavonoids at the concentration range 1-100 μM inhibited PMNs oxidative metabolism and lipid peroxidation in a dose-dependent manner. The results suggest that these flavonoids suppress the oxidative burst of PMNs and protect membranes against lipid peroxidation.

Źródło:

Acta Biochimica Polonica; 2001, 48, 1; 183-189
0001-527X

Pojawia się w:

Acta Biochimica Polonica

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 39.

Tytuł:

Coronal Electron Density Distribution Estimated from Meter Type II Radio Bursts and Coronal Mass Ejections

Autorzy:

Yusof, N. S.
Hamidi, Z. S.
Norsham, N. A.
Jafni, A. I.
Kahlid, N. M.
Hamdan, M. N.
Kamaruddin, Farahana
Tahar, Muhammad Redzuan
Monstein, C.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/1192681.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

coronal mass ejection
Type II radio burst
electron density distribution
e-CALLISTO

Opis:

In this paper, we investigate the characteristic coronal mass ejection and Type II radio burst, we calculated the drift rate of Type II Radio burst and determined the electron density distribution from a Coronal Mass Ejections. The data were taken from website e-CALLISTO, Space Weather, SolarHam and also from the Langkawi National Observatory, National Space Agency, Langkawi Kedah, Malaysia. All the data collected on 15th March 2015, 4th November 2015 and 16th December 2015. On 16 March 2015, the events were associated with slower C9 solar flare and CME. For this week, the events were causing radio blackouts on Earth. On 4 November 2015, the events were associated with M1.9 solar flare, CME and Solar burst Type II. The value of the solar wind was 570.4 km/Sec and value for radio sun was 124 sfu. For drift rate, we calculated the value for sites in Sri Lanka (ACCIMT-SRI), Ooty, India (OOTY), Indonesia (INDONESIA) and Kasi, South Korea (KASI) at between 0324 to 0328 UTC. In South Korea was highest drift rate, which is 1.397 MHz/s. Also, at HB9SCT, Switzerland (HB9SCT), Humain, Belgium (Humain), Daro, Germany (Daro-VHF) and TCD in Birr, Ireland (BIR), we calculated the drift rate of solar burst Type II between 1200 until 1203 UTC. In Belgium had the highest value of the drift rate to compare at other sites. Harmonic pattern was also appeared for all these sites. On 16th December 2015, this event associated with C6.6 solar flare and CME. These events give an impact on the earth geomagnetic field which is formed of aurora because of the combination of both events that trigger geomagnetic storming.

Źródło:

World Scientific News; 2016, 46; 19-35
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 40.

Tytuł:

An Alternating of Solar Radio Burst Type III and IV of Thermal and Non-Thermal Plasma Radiation

Autorzy:

Hamidi, Z. S.
Husien, Nurul Hazwani
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/1193005.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Sun
burst
low frequency
solar radio
type III
type IV e-CALLISTO

Opis:

A preliminary correlation study of the solar burst type III with a type Iv solar burst of has been made. On the basis of this study and in combination with the observation in radio emission, an interpretation of the mechanism of the occurrence of this event has been proposed. We have noted that an individual type III burst also can be observed at 13:54-13:58 UT from 500 MHz. Based on 3 days observation beginning from 31st March 2015, the solar activity is gradual increased. The highest solar flare can be observed is only a class of M8 flare. There was a CMEs event that directed to the Earth is detected. From the selected event, although theoretically solar radio burst type III is alternating with type IV solar burst. This huge explosion generated the M-class flare which can affect the Earth and satellites. The solar wind velocity recorded is 384.2 km/second while the density of protons is 3.6 protons/cm3. The total magnetic field during this event also quite big which is 4.6nT. The alternating of solar burst type III and IV would probably depends on the tendencies to form the CMEs event. The morphology of thermal and non-thermal flare plasma is of particular significance because it holds many important signatures of the energy release process.

Źródło:

World Scientific News; 2016, 31; 88-99
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 41.

Tytuł:

Acoustic Features of Burst Release: A Study of Welsh Plosives

Autorzy:

Jaworski, Sylwester
Baran, Michał

Powiązania:

https://bibliotekanauki.pl/articles/1753748.pdf

Data publikacji:

2021-07-30

Wydawca:

Katolicki Uniwersytet Lubelski Jana Pawła II. Towarzystwo Naukowe KUL

Tematy:

spółgłoski zwarto-wybuchowe
plozja
środek ciężkości
plosives
release burst
centre of gravity

Opis:

The aim of this paper is to analyse the centre of gravity (COG) of release bursts in Welsh plosives in order to assess their importance in distinguishing between /p, t, k/ (here termed fortis) and /b, d, g/ (here termed lenis). The COG of a release burst appears to be particularly interesting as (i) it has not yet been studied extensively in the phonetic scientific literature on Welsh plosives (see for instance Ball, Ball and Williams, Jones, Morris and Hejná), and (ii) using the COG variable to distinguish between stops is not very common, as it is normally used to differentiate between places of articulation in fricatives. To achieve the aforementioned goals, the authors, inspired by a study of American English plosives conducted by Chodroff and Wilson, measured the COG of bursts in word-initial /p, b, t, d, k, g/.
Cechy akustyczne środka ciężkości plozji: studium walijskich spółgłosek zwarto-wybuchowych Celem niniejszego artykułu jest przeanalizowanie środka ciężkości plozji walijskich spółgłosek zwarto- wybuchowych co pozwoliłoby ocenić znaczenie tego czynnika w rozróżnianiu między /p, t, k/ (w artykule określane jako mocno artykułowane – fortis) a /b, d, g/ (w artykule określane jako słabo artykułowane – lenis). Środek ciężkości plozji wydaje się szczególnie interesujący ponieważ: (i) nie był jeszcze dogłębnie analizowany w badaniach fonetycznych walijskich spółgłosek zwarto-wybuchowych (por. Ball 1984; Ball i Williams 2011; Jones 1984; Morris i Hejná 2019) oraz (ii) używanie środka ciężkości plozji jako czynnika różnicującego między spółgłoskami zwarto-wybuchowymi jest dosyć rzadkie, jako że tego czynnika używa się zwykle do różnicowania między spółgłoskami szczelinowymi o różnych miejscach artykulacji. Aby osiągnąć wspomniane wcześniej cele, autorzy artykułu, zainspirowani badaniem spółgłosek zwarto-wybuchowych amerykańskiej odmiany języka angielskiego przeprowadzonym przez duet Chodroff i Wilson (2014), zmierzyli środek ciężkości plozji w nagłosie dla /p, b, t, d, k, g/.

Źródło:

Roczniki Humanistyczne; 2021, 69, 11 Zeszyt specjalny; 89-105
0035-7707

Pojawia się w:

Roczniki Humanistyczne

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 42.

Tytuł:

Wpływ promieniowania słonecznego na wytrzymałość tkanin zewnętrznych ubrania specjalnego strażaka
Impact of solar radiation on the resistance of external textile used in special firefighter clothing

Autorzy:

Kamocka-Bronisz, R.
Bronisz, S.

Powiązania:

https://bibliotekanauki.pl/articles/136895.pdf

Data publikacji:

2018

Wydawca:

Szkoła Główna Służby Pożarniczej

Tematy:

odzież ochronna
starzenie
wytrzymałość
przebicie kulką
protective clothing
aging
strength
ball burst

Opis:

Tkaniny przeznaczone do produkcji odzieży ochronnej dla strażaków muszą zapewniać dostateczny poziom bezpieczeństwa podczas wykonywanych działań przez ratowników. Przeprowadzone badania, które opisano w artykule, miały na celu pokazanie zmian zachodzących w tkaninach w czasie ich przyspieszonego starzenia, do którego wykorzystano lampę ksenonową. Ocenę prowadzono na podstawie badań wytrzymałości na przebicie kulką po cyklu starzenia.
Textiles intended for protective clothing shall provide the fireman with sufficient safety during operations. The aim of the conducted research was to demonstrate changes occurring in the textiles in conditions of accelerated aging using xenon lamp. The assessment of wear was based on the textile’s residual ball bursting strength after an aging cycle.

Źródło:

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej; 2018, 2, 66; 27-34
0239-5223

Pojawia się w:

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 43.

Tytuł:

Analiza zużycia tkaniny zewnętrznej ubrania specjalnego dla strażaków
Analysis of the wear of special firefighters’ clothing external outershell

Autorzy:

Kamocka-Bronisz, R.
Bronisz, S.

Powiązania:

https://bibliotekanauki.pl/articles/136964.pdf

Data publikacji:

2017

Wydawca:

Szkoła Główna Służby Pożarniczej

Tematy:

odzież ochronna
ścieranie
wytrzymałość
przebicie kulką
protective clothing
abrasion
strength
ball burst

Opis:

Tkaniny przeznaczone na odzież ochronną należą do grupy wyrobów narażonych na trudne warunki eksploatacyjne: działanie sił tarcia i wielokierunkowego rozciągania. Przeprowadzone badania, których wyniki opisano w artykule, miały na celu pokazanie zmian zachodzących w tkaninach w czasie ich przyspieszonego zużycia – ścierania. Ocenę zużycia prowadzono na podstawie badań wytrzymałości resztkowej na przebicie kulką po cyklach ścierania dla czterech rodzajów tkanin. Badania porównawcze pozwoliły na ocenę ich przydatności i optymalizację doboru tkaniny zewnętrznej ubrania specjalnego strażaka.
Fabrics intended for protective clothing belong to a group of materials subjected to difficult operating conditions: frictional forces and multidirectional tensile. The conducted studies,which results have been presented in the article, aimed at demonstrating changes occurring in the fabrics at conditions of accelerated wear – abrasion. The assessment of wear, based on the studies of residual ball bursting strength after abrasion for 4 types of fabrics, was performed. Comparative studies have allowed to assess the fabrics usefulness and optimise the choice for the firefighters’ protective clothing.

Źródło:

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej; 2017, 2, 62; 7-23
0239-5223

Pojawia się w:

Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 44.

Tytuł:

The Development of the X2-Class of flares with Presence of Type IV burst and Single Type III burst in Low Frequency (20-85 MHz) on 5th May 2015

Autorzy:

Sabri, S. N. U.
Hamidi, Z. S.
Shariff, N. N. M.
Zainol, N. H.
Syazwan, Nabilah Ramli
Ali, Marhana Omar
Husien, Nurulhazwani
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/1191466.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Sun
solar burst
III
IV
X-ray region
solar flare
Active Region 2335

Opis:

The plasma-magnetic field interaction in the solar corona is caused exploration of suprathermal electron population have been made to study about the phenomena solar radio burst. This burst only took about approximately 2 minutes to produce X2- class of solar flares which occurred at 22:10 UT till 22:11UT. The wave-wave interaction and wave-particle interaction influenced the characteristic structures of the emission. The CALLISTO spectrometer has been used to detect and record the Type IV and Type III occurred during 22:07UT till 22:11 UT and it only took about 3.30 minutes to occur. The range of frequency of this burst 20-85 MHz and data is from ROSWELL-NM observatory. With the presence of the data, we aim to determine the causes of the Solar Radio Burst Type IV produced Type III burst in several minutes and describe briefly about the formation and dynamics of solar radio burst type IV occurred on active region, AR2335 which also produced beta-gamma magnetic field. This event showed the strong pulsation and a broadband pattern with details about Type IV burst, then Type III burst present in fast drift. AR 2335 is the most active region and produced X2-class of solar flares which has solar wind speed about 361.6km/second and proton density about 4.3 protons/cm3 in the solar corona. AR 2335 harbor energy for X2-class from 6-H to 24-H observation on X-Ray solar flares have been recorded. The data showed that it has a strong energy electrons presence during the burst occurred in the active region and this class of solar flares are more powerful which has potential to cause radio blackout and long lasting space weather storms. As the conclusion, the sun activity showed on 5th May 2015 has quasi-periodic pulsation that has continuum and drift in lower frequency. The temperature that corona took to extend from the top of a narrow transition region still be as mysterious properties.

Źródło:

World Scientific News; 2016, 40; 188-198
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 45.

Tytuł:

The Development of Solar Prominence on 4th September 2015 and the Solar Burst Type III and IV

Autorzy:

Norsham, N. A.
Hamidi, Z. S.
Mazlan, Muzamir
Shariff, N. N. M.
Yusofl, N. S.
Jafni, A. I.
Khalib, N. M. F.
Hamdan, M. N.
Kamaruddin, Farahana
Tahar, Muhammad Redzuan
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/1192156.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Solar prominences
active region (AR)
solar burst
type III
type IV
e CALLISTO

Opis:

This article will focus on the solar prominences that occur during the 4th September 2015. On that day, there were two sunspots on the surface of the sun, which were AR2409 and AR2410. These two active regions did not produce any threat for strong flare and thus the solar activity was very low. The prominences that will be focused were both occurred at 0353 UT and 0427 UT respectively. There were minor (G1) geomagnetic storm observed on that day. For solar prominences that occurred at 0353 UT, solar radio burst type (SRBT) IV was detected by CALLISTO spectrometer. From the CALLISTO, two bursts at low intensities with the duration of about 7 minutes for the first burst of 280-320 MHz and 6 minutes for the second burst of 360-430 MHz were observed. For the first burst, energy calculated was between 1.855 x 10 -25 J and 2.12 x 10 -25 J with the drift rate of 0.095 MHz/s. For second burst, the energy obtained was between 2.385 x 10 -25 J and 2.849 x 10 -25 J with the drift rate of 0.194 MHz/s. At 0427 UT, SRBT III was recorded with a frequency of 240-350 MHz with the energy which was obtained between 1.590 x 10 -25 J and 2.319 x 10 -25 J. The drift rate of this type of burst was 0.61 MHz/s. During this event, the solar wind value was 499.3 km/Sec with the proton density of 15.1 protons/cm3.

Źródło:

World Scientific News; 2016, 45, 2; 264-275
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 46.

Tytuł:

Probability of Solar Flares Turn Out to Form a Coronal Mass Ejections Events Due to the Characterization of Solar Radio Burst Type II and III

Autorzy:

Hamidi, Z. S.

Powiązania:

https://bibliotekanauki.pl/articles/412360.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

solar flare
Coronal Mass Ejection
solar burst
type II
type III
space Feather

Opis:

The solar flare and Coronal Mass Ejections (CMEs) are well known as one of the most massive eruptions which potentially create major disturbances in the interplanetary medium and initiate severe magnetic storms when they collide with the Earth‟s magnetosphere. However, how far the solar flare can contribute to the formation of the CMEs is still not easy to be understood. These phenomena are associated with II and III burst it also divided by sub-type of burst depending on the physical characteristics and different mechanisms. In this work, we used a Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatories (CALLISTO) system. The aim of the present study is to reveal dynamical properties of solar burst type II and III due to several mechanisms. Most of the cases of both solar radio bursts can be found in the range less that 400 MHz. Based on solar flare monitoring within 24 hours, the CMEs that has the potential to explode will dominantly be a class of M1 solar flare. Overall, the tendencies of SRBT III burst form the solar radio burst type III at 187 MHz to 449 MHz. Based on solar observations, it is evident that the explosive, short time-scale energy release during flares and the long term, gradual energy release expressed by CMEs can be reasonably understood only if both processes are taken as common and probably not independent signatures of a destabilization of pre-existing coronal magnetic field structures. The configurations of several active regions can be sourced regions of CMEs formation. The study of the formation, acceleration and propagation of CMEs requires advanced and powerful observational tools in different spectral ranges as many „stages‟ as possible between the photosphere of the Sun and magnetosphere of the Sun and magnetosphere of the Earth. In conclusion, this range is a current regime of solar radio bursts during CMEs events.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 16; 1-85
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 47.

Tytuł:

Radio Observation of Coronal Mass Ejections (CMEs) Due to Flare Related Phenomenon on 7th March 2012

Autorzy:

Hamidi, Z. S.
Monstein, C.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/412379.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Radio burst
solar flare
Coronal Mass Ejections (CMEs)
e-CALLISTO
Active Region 1429

Opis:

On March 7th, 2012, an active region AR1429 has unleashed 2 major X-class solar flares. This flare is accompanied by a Coronal Mass Ejections (CMEs) event. A pair of unusually large solar flares early March 7, 2012 generated a Coronal Mass Ejection that was expected to reach Earth around midday March 8. In this case we focused on the second explosion of solar flare. It is found that the indication of signal potentially drives Coronal Mass Ejections (CMEs). There are a few types solar burst that can be observed, which is (i) an individual type III (ii) a complex type III (iii) subtype an H type II solar burst and (iv) type IV solar burst. The duration of solar burst is start from 1:02 UT to 2:00 UT. We also compare our results with the Geostationary Operational Environmental Satellites (GOES) data. Overall, one hour duration with a strong intensity burst are exploded strongly within the period. The fast drift type III burst has continued until 1:28 UT is associated with the large X 5.4 -class solar flares at 1:25:05 UT. It is undeniable that solar flare plays an important role in the Sun-Earth connection due to sudden changes of strong magnetic fields in the Sun’s corona. From our analysis, one possible reason behind the formation of this very complex, long duration of this loop is the magnetic reconnection and disruption of the loops which is observed during flare maximum. Until now, there has been an increasing interest in the space weather program has stimulated interest in this issue. A new experimental approach by e-CALLISTO with 24 hours monitoring and further development of a model of the theory are hoping to meet the current knowledge about the Sun behaviour.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 11, 3; 243-256
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 48.

Tytuł:

Próba określenia dynamicznej mocy stojaka zmechanizowanej obudowy ścianowej przeznaczonego do pracy w warunkach zagrożenia wstrząsami górotworu – artykuł dyskusyjny
An attempt to determine the dynamic power of mechanized longwall housing leg designed to work in hazardous conditions of rock mass tremors – discussion article

Autorzy:

Szurgacz, D.

Powiązania:

https://bibliotekanauki.pl/articles/340913.pdf

Data publikacji:

2011

Wydawca:

Główny Instytut Górnictwa

Tematy:

wstrząsy górotworu
zmechanizowana obudowa ścianowa
stojak
rock burst hazard
mechanized longwall housing
stand

Opis:

W artykule podjęto próbę określenia dynamicznej mocy stojaka pracującego w warunkach zagrożenia wstrząsami górotworu. Na podstawie badań eksperymentalnych dynamicznych zjawisk ciśnienia górotworu, mającego bezpośredni wpływ na obudowę zmechanizowaną, jak również pomiarów drgań występujących blisko ognisk wstrząsów górotworu, opracowano prezentowaną metodę. Opisano zakres analityczny metody oceny obciążenia i prób zabezpieczenia zmechanizowanej obudowy ścianowej, pracującej w warunkach dynamicznych obciążeń górotworu, z zastosowaniem pojęcia mocy.
The article presents the attempt to determine the dynamic power of a working leg in hazardous conditions of rock mass tremors. The research is based on experimental studies of dynamic phenomena of rock pressure which have a direct impact on the mechanized housing, as well as measurements of vibrations occurring near the outbreak of rock mass tremors. This paper describes the range of analytical methods assessing the load and the tests of the security of mechanized longwall housing working in a dynamic load of the rock mass.

Źródło:

Prace Naukowe GIG. Górnictwo i Środowisko / Główny Instytut Górnictwa; 2011, 1; 79-87
1643-7608

Pojawia się w:

Prace Naukowe GIG. Górnictwo i Środowisko / Główny Instytut Górnictwa

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 49.

Tytuł:

Determination of Flux Density of the Solar Radio Burst Event by Using Log Periodic Dipole Antenna (LPDA)

Autorzy:

Hamidi, Z. S.
Shariff, N. N. M.

Powiązania:

https://bibliotekanauki.pl/articles/412450.pdf

Data publikacji:

2014

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

sun
CALLISTO
Log Periodic Dipole Antenna (LPDA)
power flux density
solar radio burst

Opis:

In this article, an evaluation of the flux density of the solar radio burst is presented. A rod aluminium’s type as a conductor with nineteenth (19) elements of different sizes is being prepared to construct a log periodic dipole antenna (LPDA) from 45-870 MHz. The performance was carried out at the National Space Agency (PAN), Sg. Lang, Banting Selangor by connecting to the Compound Low Cost Low Frequency Spectroscopy Transportable Observatory (CALLISTO) spectrometer. The input impedance, R0 = 50 ohm is chosen for this LPDA antenna. From the analysis, the gain of the antenna is 9.3 dB. This antenna potentially captures a signal that covers about 0.08 m2 area of the Sun.The temperature of the burst that detected at the feedpoint of the antenna is 32 K. However, the signal becomes decrease to 28.75 K while by CALLISTO spectrometer as a receiver. It was also found that the isotropic source spectral power is 1576 W/Hz. Since the burst level above the background sky is 0.41 dB , the flux density of the burst is 5.5 x 10-21 W/m2/Hz. Based on the results, we conclude that this antenna is suitable for to observe the Sun activities at low frequency region.

Źródło:

International Letters of Chemistry, Physics and Astronomy; 2014, 7; 21-29
2299-3843

Pojawia się w:

International Letters of Chemistry, Physics and Astronomy

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce

Skocz do pozycji: 50.

Tytuł:

The zigzag pattern construction of Log Periodic Dipole Antenna Based on Rumsey’s Principle

Autorzy:

Hamidi, Z. S.
Saad, M. Azren Mat
Shariff, N. N. M.
Monstein, C.

Powiązania:

https://bibliotekanauki.pl/articles/1188094.pdf

Data publikacji:

2016

Wydawca:

Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN

Tematy:

Log Periodic Dipole Antenna
zigzag pattern
solar burst
radio region
Rumsey’s principle

Opis:

The log-periodic dipole array (LPDA) consist of an array of dipoles in which there have a different lengths and spacing. The wire may be straight or it may be strung back and forth between trees or walls just to get enough wire into the air; this type of antenna sometimes is called a zigzag antenna. Rumsey’s principle requires that the locations of all elements be specified by angles rather than distances, because of this the log periodic dipole array must be correspondingly longer to get very wide bandwidths and gives a very high data rate transmission. The significance of this study is to understand how do the LPDA can be used to monitor solar activities of the sun using the LPDA antenna. The characteristics that need to be considered during construct this antenna is the radiation pattern, polarization, operation of the frequency band, gain and efficiency of an antenna which indicates the power or field strength radiated in any direction relative to that in the direction of maximum radiation. The arrangement of elements in increasing order from the top of the antenna until the bottom part of antenna. Our designed antenna was constructed using aluminum for the further investigation, we can use a copper and check the difference between two of this element. For this study, we just analyzed the source of RFI using this antenna and for the further analysis, we can use this antenna to monitor the solar burst.

Źródło:

World Scientific News; 2016, 56; 146-157
2392-2192

Pojawia się w:

World Scientific News

Dostawca treści:

Biblioteka Nauki

/5

Artykuł

Zmień widok

• na półce