Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Wang, Z. Y." wg kryterium: Autor


Tytuł:
Rotor power loss in a PM SM by calculation, simulation and measurements, mutual verification of methods
Autorzy:
Vannier, J. C.
Kaczmarek, R.
Wang, Z. Y.
Randria, A.
Powiązania:
https://bibliotekanauki.pl/articles/262831.pdf
Data publikacji:
2006
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
Tematy:
synchronous machine
permanent magnet
eddy current loss
equivalent circuit
Opis:
The subject of the paper is the comparison of four complementary methods of the rotor loss estimation in a PM SM, supplied by a PWM voltage source. An ANSYS based finite element model produces values of W, the magnetic energy stored, and P, the rotor losses. On analytical level the machine is represented by a parallel two elements equivalent circuit for each voltage harmonic. Its parameters are estimated using P and W values. Finally, the eddy current losses representation in the ANSYS code is verified for magnets under study by direct losses measurements. The calculation results are compared with some measured values resulting from analysis and harmonic decomposition of the machine total losses.
Źródło:
Electrical Power Quality and Utilisation. Journal; 2006, 12, 2; 113-116
1896-4672
Pojawia się w:
Electrical Power Quality and Utilisation. Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isolation and sequence analysis of the complete VP2 gene of canine parvovirus from Chinese domestic pets and determination of the pathogenesis of these circulating strains in beagles
Autorzy:
Chen, M.R.
Guo, X.Y.
Wang, Z.Y.
Jiang, Y.T.
Yuan, W.F.
Xin, T.
Hou, S.H.
Song, T.Q.
Lin, W.D.
Zhu, H.F.
Jia, H.
Powiązania:
https://bibliotekanauki.pl/articles/2087542.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
canine parvovirus
molecular epidemiology
phylogenetic analysis
pathogenesis
Źródło:
Polish Journal of Veterinary Sciences; 2019, 2; 287-296
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation on different behavior and mechanism of Ca(II) and Fe(III) adsorption on spodumene surface
Autorzy:
Yu, F.
Wang, Y.
Wang, J.
Xie, Z.
Powiązania:
https://bibliotekanauki.pl/articles/110230.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
spodumene surface
calcium ions
iron ions
adsorption mechanism
DFT calculation
Opis:
Behavior and mechanism of Ca2+ and Fe3+ adsorption on spodumene surface were investigated by micro flotation tests, zeta potential measurements, and density functional theory (DFT) calculation methods. The micro flotation tests showed that Ca2+ and Fe3+ activated the flotation of spodumene remarkably. However, the effect of Fe3+ was more significant than that of Ca2+. Additionally, Fe3+ significantly changed the zeta potential of spodumene while Ca2+ showed a little change. Meanwhile, the calculated adsorption energy of Fe3+ on spodumene surface was much greater than that of Ca2+ indicating that Fe3+ is more apt to be adsorbed on spodumene surface than Ca2+. The value of bond population in Ca-O illustrated that the bond of Ca-O consists of partial covalent proportion and some ionic component. On the contrary, the bond of Fe-O showed a relatively strong covalent property. The partial density of states (PDOS) of free Ca/Fe and the reacted O atom on spodumene (110) surface before and after the adsorption showed that Fe 3d orbital and O 2p orbital formed hybridization. The density of states (DOS) near the Fermi level of spodumene surface after adsorption with Fe3+ was much stronger than that with Ca2+.
Źródło:
Physicochemical Problems of Mineral Processing; 2014, 50, 2; 535-550
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Visualization investigation on the marine data with multivariate statistical analysis methods
Autorzy:
Li, Y.
Lu, Z.
Wang, M.
Powiązania:
https://bibliotekanauki.pl/articles/260477.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine data
factor analysis
cluster analysis
discriminate analysis
visualization
Opis:
Marine information is an important way for us to know and study more about the ocean. Marine data makes the basic of marine information. Because of the huge quantity and diversity of marine data, and at the same time marine data is polyatomic variable, we start with statistical analysis methods to search for the regularity of the marine data. On one hand, we get the aggregate variation functions of the marine data by factor analyzing in aspect of the spatiality. Then we visually describe the marine status of the studied sea area with pre variogram function and post variogram function. On the other hand, we used cluster analysis method to get the verifying rule in time and make visible graphs of the marine data. In this way, we can also supply with the suggestions in classifying the sea seawater quality. The data processing result shows that the suggested methods in this article are both operable and effective. At the same time some reasonable suggestions are given in the article.
Źródło:
Polish Maritime Research; 2017, S 2; 89-94
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new fossil lacewing genus and species from the Middle Jurassic of Inner Mongolia, China
Autorzy:
Wang, Y
Liu, Z.
Ren, D.
Powiązania:
https://bibliotekanauki.pl/articles/22432.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
new fossil
fossil
paleontology
systematics
lacewing genus
lacewing species
Middle Jurassic
Jurassic
Inner Mongolia
China
Tenuosmylus brevineurus
Poriminae
Eidoporisminae
Stenosmylinae
Opis:
A new fossil lacewing, Tenuosmylus brevineurus gen. et sp. nov., was collected from an outcrop of Middle Jurassic strata in the village of Daohugou, Inner Mongolia, China. The new genus is assigned to Gumillinae based on eleven defining characteristics of the subfamily. The affiliation of Tenuosmylus including other five genera of the subfamily is discussed. Our result supports the opinion that Epiosmylinae was a junior synonym of Gumillinae, which is likely a relic of ancient osmylids based on similarity of forewing venation. Veins Mp₂ and Cu₂ have complicated branches that are generally present in extinct as well as some extant subfamilies (Poriminae, Eidoporisminae, Stenosmylinae). A key is given to differentiate six known genera within Gumillinae.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 3; 557-560
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Integrated decision on spare parts ordering and equipment maintenance under condition based maintenance strategy
Zintegrowany system decyzyjny dotyczący zamawiania części zamiennych i utrzymania ruchu urządzeń w ramach strategii utrzymania zależnej od bieżącego stanu technicznego
Autorzy:
Wang, Y.
Zhao, J.
Cheng, Z.
Yang, Z.
Powiązania:
https://bibliotekanauki.pl/articles/301823.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
spare parts
inventory control
ordering
condition based maintenance
Monte Carlo simulation
części zamienne
kontrola zapasów
zamówienia
utrzymanie zależne od bieżącego stanu technicznego
symulacja Monte Carlo
Opis:
Aiming to optimize the equipment maintenance and the spare parts ordering management jointly, a comprehensive decision model under condition based maintenance (CBM) policy is presented for a single equipment system with continuous and random deterioration. In this model, the equipment deterioration is a continuous Gamma process under a continuous condition monitoring, and the spare parts inventory is controlled by spare parts support probability. Firstly, a spare part support probability model was developed to determine the optimal spare parts stock level S, which is set to meet the requirement of a predetermined stockout probability. Secondly, the equipment replacement and spare parts ordering decision is made to optimize the equipment replacement and spare parts ordering jointly, which is based on the equipment deterioration leveland total operating cost of the system. Thirdly, an integrated decision simulation model is presented for evaluating cost rate, availability and stockout probability. Finally, a numerical example is given to illustrate the performance of this model. The results show that the optimal preventive maintenance threshold obtained from the proposed decision model can satisfy the spare parts support requirements under (S-1, S) inventory control strategy.
Dążąc do jednoczesnej optymalizacji utrzymania ruchu urządzeń i zarządzania zamówieniami części zamiennych, zaproponowano kompleksowy model decyzyjny w ramach strategii utrzymania zależnej od bieżącego stanu technicznego (CBM) przeznaczony dla systemów z pojedynczym urządzeniem i ciągłym oraz losowym zużyciem. W niniejszym modelu, zużycie urządzenia jest ciągłym procesem Gamma z ciągłym monitorowaniem stanu, podczas gdy zapasy części zamiennych są kontrolowane poprzez prawdopodobieństwo wsparcia w zakresie części zamiennych. Po pierwsze, opracowano model prawdopodobieństwa wsparcia w zakresie części zamiennych w celu określenia optymalnego poziomu zapasów części zamiennych S, ustalonej aby spełnić wymogi określonego prawdopodobieństwa braku dostępności. Po drugie, przeprowadzono proces decyzyjny dotyczący wymiany urządzenia i zamawiania części zamiennych w celu jednoczesnej optymalizacji wymiany urządzenia i zamawiania części zamiennych, w oparciu o poziom zużycia urządzenia i całkowity koszt działania systemu. Po trzecie, zaprezentowano zintegrowany symulacyjny model decyzyjny dla oceny poziomu kosztów, dostępności i prawdopodobieństwa jej braku. Zasady niniejszego modelu zilustrowano przykładem numerycznym. Wyniki pokazują, że optymalny próg konserwacji zapobiegawczej uzyskany za pomocą proponowanego modelu decyzyjnego może spełnić wymagania dotyczące części zamiennych w ramach (S-1, S) strategii kontroli zapasów.
Źródło:
Eksploatacja i Niezawodność; 2015, 17, 4; 591-599
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic and resonance response analysis for a turbine blade with varying rotating speed
Autorzy:
Wang, D.
Hao, Z.
Chen, Y.
Zhang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/280027.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
varying rotating speed
van der Pol oscillation
ultiple scale methodnonlinear response
bifurcation curve
Opis:
A coupling model between turbine blades with a varying rotating speed and oncoming vortices is constructed, where the coupling of the structure and the fluid is simulated by the van der Pol oscillation. Partial differential governing equations of motions for the coupled system are obtained and discretized by using the Galerkin method. The 1:2 subharmonic resonance and the 1:1 internal resonance are investigated with the multiple scale method and first-order averaged equations are then derived. Nonlinear responses and bifurcation characteristics are studied by a numerical integration method. Stability of bifurcation curves is determined by utilizing the Routh-Hurwitz criterion. The effect of system parameters including the detuning parameter, steady-state rotating speed, amplitude of periodic perturbation for the rotating speed and freestream velocity on vibration responses are investigated.
Źródło:
Journal of Theoretical and Applied Mechanics; 2018, 56, 1; 31-42
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on contact between double metal composite and pipe power slip for offshore well
Autorzy:
Wang, Y.
Ai, Z.
Shi, C.
Ai, Y.
Powiązania:
https://bibliotekanauki.pl/articles/258954.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
power slip
double metal composite pipe
contact area
slip teeth
plastic damage
Opis:
The whole process of clamping offshore well double metal composite pipe was established, Reviewing the problems that in the oil and gas wells the double metal composite pipes frequently get plastic damage or even fracture failure when the power slips hold fast to the double metal composite pipe, the effect Eq. of contact area to tooth plate and double metal composite pipe was deduced, and based on the elastoplastic contact analysis theory, the theoretical Eq. was verified. For the double metal composite pipe stress, displacement and stress of drill tooth plate, influence of slip teeth plate on the double metal composite pipe damage was analyzed, The plastic damage law of the double metal composite pipe was obtained with the influence factor of the contact surface and the influence factor of the tooth crown width. the analysis showed that, The double metal composite pipe can be clamped and the contact area value of the tooth plate with the minimum damage are fixed. Several sets of teeth were produced, and then used to carry out experiments, indoor and field experiments have fully proved the accuracy of the result, The research work provides a better theoretical basis for optimal design of slip tooth plate.
Źródło:
Polish Maritime Research; 2017, S 2; 66-73
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
3D morphological reconstruction of the red blood cell based on two phase images
Autorzy:
Wang, Y
Li, Z
Ji, Y
Xu, Y
Bu, M
Powiązania:
https://bibliotekanauki.pl/articles/174332.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
phase imaging
red blood cell
3D morphological reconstruction
maximum entropy
Opis:
As an important component of blood cells, the red blood cell plays a vital role in many diseases such as malaria and so on. Although quantitative phase imaging techniques can be used for homogeneous cellular thickness distribution to obtain ideal results, they cannot achieve 3D morphological distribution. In this paper, a new method is presented to get a 3D morphology image of red blood cell. With this method, only two cellular quantitative phase images obtained from two orthogonal directions are needed as original information. By using the grid method, the sample is divided into many small phase cubes, and then we take a layer’s cubes into calculation so that the 3D problem could be transformed into a 2D problem to elaborate. Then it can be applied to the tomographic imaging combined with the maximum entropy method according to the two orthogonal phase images. This method has been proved by a simulation of red blood cell. The results show that cellular morphological distribution can be achieved in detail very well just based on only two orthogonal phase images.
Źródło:
Optica Applicata; 2015, 45, 2; 173-182
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parameter Description of the Surface Metal Fiber Arrangement of Electromagnetic Shielding Fabric
Wpływ rozmieszczenia włókien metalowych na skuteczność ekranowania tkanin osłonowych
Autorzy:
Liu, Z.
Su, Y.
Pan, Z.
Li, Y.
Wang, X.
Zhou, Z.
Powiązania:
https://bibliotekanauki.pl/articles/232915.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
electromagnetic shielding fabric
surface metal fiber blends
surface metal arrangement
tkanina ekranująca
tkanina osłonowa elektromagnetyczna
układ metalowy powierzchni
Opis:
The influence of the surface metal fiber (SMF) arrangement on the shielding effectiveness (SE) of electromagnetic shielding fabric (EMSF) is important, but there is no reasonable description method for it at present, making the further exploration of the relationship between SMF and SE difficult. In order to scientifically describe the SMF arrangement of EMSF, this paper constructs a binary feature matrix of SMF based on a previous study of SMF region recognition. According to the feature matrix, three parameters of the exposure ratio, the discrete mean and disorder degree are proposed and the calculation equations for the three parameters given. Experiments were designed and testing samples determined to test the SE, and the exposure ratio, discrete mean and disorder degree of each sample are calculated. The relationship between the three parameters and the SE is analysed for effectiveness validation of the three parameters. Results show that the exposure ratio, discrete mean and disorder degree can describe three aspects of the SMF arrangement: the percentage content, porosity and orientation, which are positively correlated, negatively correlated and positively correlated to the SE, respectively. The research in this paper provides a basis for the study of the shielding mechanism, the transmission model, the shielding rule and the rapid non-destructive evaluation of the EMSF, and puts forward a new idea for the study of shielding theory and the application of the EMSF.
Ze względu na istotny wpływ rozmieszczenia włókien metalowych (SMF) na skuteczność ekranowania (SE) tkanin osłonowych (EMSF) w pracy przedstawiono macierz binarną opartą na trzech parametrach włókien metalowych tj.: współczynniku ekspozycji, średniej wartości odległości między włóknami metalowymi i stopniu ich nieuporządkowania. Analizowano zależności pomiędzy wyżej wymienionymi parametrami a skutecznością ekranowania. Przedstawione wyniki stanowią podstawę do opracowania szybkiej i nieniszczącej metody oceny skuteczność ekranowania oraz do dalszych badań mechanizmu ekranowania.
Źródło:
Fibres & Textiles in Eastern Europe; 2017, 2 (122); 62-67
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vertical transmission of PCV2b to fetuses in sows intramuscularly infected with PCV2b
Autorzy:
Wang, N.D.
Li, J.J.
Wang, A.B.
Zhu, Z.
Chang, Y.
Mao, Y.
Zan, Y.
Wang, Z.F.
Deng, Z.B.
Powiązania:
https://bibliotekanauki.pl/articles/31535.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
In order to investigate whether PCV2b can be transmitted across the placenta in sows thereby causing vertical infection of fetuses, six sows in 75 day of pregnancy were either intramuscularly inoculated with a PCV2b culture supernatant (n = 4) or mock infected with cell culture supernatant (n = 2). At parturition, 3 newborn piglets from each litter were randomly selected and euthanatized prior to suckling. Samples of the mesenteric lymph nodes, spleens, kidneys, hearts and lungs were collected for PCR, histopathological and immunohistochemical assays. The results showed that the newborn piglets from PCV2b-infected sows had histopathological lesions in the tested tissues. Moreover, PCV2b antigen and DNA were detected as well. These findings therefore suggested that porcine circovirus type 2b can be transmitted across the placenta of sows, thereby leading to PCV2b vertical infection of the fetuses.
Źródło:
Polish Journal of Veterinary Sciences; 2016, 19, 3
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Morphology and developmental traits of the trilobite Changaspis elongata from the Cambrian Series 2 of Guizhou, South China
Autorzy:
Du, G.-Y.
Peng, J.
Wang, D.-Z.
Wang, Q.-J.
Wang, Y.-F.
Zhang, H.
Powiązania:
https://bibliotekanauki.pl/articles/22906.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
The morphology and ontogeny of the trilobite Changaspis elongata based on 216 specimens collected from the Lazizhai section of the Balang Formation (Stage 4, Series 2 of the Cambrian) in Guizhou Province, South China are described. The relatively continuous ontogenetic series reveals morphological changes, and shows that the species has seventeen thoracic segments in the holaspid period, instead of the sixteen as previously suggested. The development of the pygidial segments shows that their number gradually decreases during ontogeny. A new dataset of well-preserved specimens offers a unique opportunity to investigate developmental traits after segment addition is completed. The ontogenetic size progressions for the lengths of cephalon and trunk show overall compliance with Dyar’s rule. As a result of different average growth rates for the lengths of cephalon, trunk and pygidium, the length of the thorax relative to the body shows a gradually increasing trend; however, the cephalon and pygidium follow the opposite trend. Morphometric analysis across fourteen post-embryonic stages reveals growth gradients with increasing values for each thoracic segment from anterior to posterior. The reconstruction of the development traits shows visualization of the changes in relative growth and segmentation for the different body parts. The new dataset and growth gradient of the trunk suggest that the thoracic segment growth dynamics of early Cambrian to Silurian trilobites follow the same general continuous, steady-state growth gradient decreasing from posterior to anterior.
Źródło:
Acta Palaeontologica Polonica; 2019, 64, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis, Structure and Energetic Properties of a Catenated N6, Polynitro Compound: 1,1’-Azobis(3,5-dinitropyrazole)
Autorzy:
Li, Y.-N.
Shu, Y.-J.
Wang, Y.-L.
Wang, B.-Z.
Zhang, S.-Y.
Bi, F.-Q.
Powiązania:
https://bibliotekanauki.pl/articles/358573.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
energetic compound
1,1’-azobis(3,5-dinitropyrazole)
synthesis
energetic properties
Opis:
A nitrogen-rich, polynitro energetic compound with an N,N-azo linkage, 1,1’-azobis(3,5-dinitropyrazole) (ABDNP), has been synthesized by an oxidative coupling reaction of 1-amino-3,5-dinitropyrazole with different oxidizing agents. The target compound was characterized by IR spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy, elemental analysis, mass spectra, X-ray diffraction and differential scanning calorimetry (DSC). The DSC results show that 1,1’-azobis(3,5-dinitropyrazole) decomposes at a relatively high onset temperature (202.9 °C), which indicates that 1,1’-azobis(3,5-dinitropyrazole) has acceptable thermal stability. The energetic properties were obtained, with a measured density and heat of formation matched by theoretically computed values based on the B3LYP method.
Źródło:
Central European Journal of Energetic Materials; 2017, 14, 2; 321-335
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of WO3 on the morphology and photodegradation of dimethyl phthalate of TiO2 nanotube array photoelectrode
Autorzy:
Xin, Y.
Wang, G.
Liu, Y.
Zang, Z.
Gao, M.
Powiązania:
https://bibliotekanauki.pl/articles/206886.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
degradation
esters
morphology
scanning electron microscopy
tungsten
water treatment
degradacja
estry
morfologia
skaningowa mikroskopia elektronowa
wolfram
oczyszczalnia ścieków
Opis:
WO3 modified TiO2 nanotube array (WO3/TNAs) photoelectrodes were fabricated via electrochemical deposition on TNAs/Ti photoelectrodes. The morphology and structure of WO3/TNAs photoelectrodes were investigated by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The effects of deposition potential, deposition duration, NaWO4 concentration, and calcination temperature on the morphology and the photocatalytic activity were investigated. The results showed that suitable amounts of WO3 promoted the photocatalytic activity of TNAs photoelectrodes for the degradation of dimethyl phthalate (DMP). The optimal conditions for the fabrication of WO3/TNAs photoelectrodes were as follows: deposition voltage 3.0 V, 10 min deposition duration, 0.01 mol/dm3 Na2WO4 concentration, 1.5 cm electrode gap, and 550 °C annealing temperature. The degradation rate of DMP reached 77% after 60 min of illumination by WO3/TNAs photoelectrode. Additionally, WO3/TNA photoelectrodes possessed superb stability for maintaining a high DMP degradation efficiency at more than 75% after 10 times of successive use with 60 min irradiation for each cycle. The enhancement of photocatalytic performance by the efficient combination of WO3 with TNAs would provide a theoretical basis for the practical application of WO3/TNA photoelectrodes in water treatment.
Źródło:
Environment Protection Engineering; 2018, 44, 3; 129-139
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seismic damage behaviour of aeolian sand reinforced concrete columns with I-shaped structural steel
Autorzy:
Wang, Y. H.
Wang, H. Y.
Wang, Y. P.
Zhao, M.
Qi, J.
Huo, G. Z.
Liu, P. Q.
Powiązania:
https://bibliotekanauki.pl/articles/1849772.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
piasek eoliczny
słup żelbetowy
stal konstrukcyjna
przekrój I
zachowanie
uszkodzenie sejsmiczne
model uszkodzenia
aeolian sand
column
I-shaped steel
structural steel
seismic damage
behaviour
damage model
Opis:
To promote the application of aeolian sand resources for steel-concrete composite structures, an aeolian sand reinforced concrete column with I-shaped structural steel is proposed in this study. Four specimens are designed and manufactured with different replacement rates of aeolian sand. The seismic behaviour and damage evolution process of the specimens are studied by low-cycle repeated loading tests. Based on the test results, the mechanical characteristics, failure modes, hysteresis curves, skeleton curves, energy dissipation capacity, displacement ductility, and stiffness degradation of the specimens with different replacement rates of aeolian sand are analysed. In addition, the effects of the design parameters on the seismic behaviour of the specimens are also studied. The results show that the indexes of the seismic behaviour can be significantly improved by adding steel. Moreover, a revised damage model is proposed, to better reflect the evolution law of seismic damage of aeolian sand reinforced concrete columns with steel. The proposed model can provide an important reference for seismic damage assessment of the columns.
Źródło:
Archives of Civil Engineering; 2020, 66, 4; 633-650
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculation of laser radar cross-section of a spatial object and its experimental verification
Autorzy:
Cao, Y.-H.
Wang, Z.
Bai, L.
Wu, Z.
Li, H.-Y.
Li, Y.-H.
Powiązania:
https://bibliotekanauki.pl/articles/174167.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
bidirectional reflectance distribution function
BRDF
laser radar cross-section
LRCS
spatial object
Opis:
Bidirectional reflectance distribution function of some artificial satellite used materials at the wavelength of 1.06 μm was measured in laboratory. Bidirectional reflectance distribution function (BRDF) models of these materials were established with the five-parameter BRDF model. Laser radar cross-section of a scaled satellite with various materials was calculated, and characteristics of laser radar cross-section of the satellite were discussed. Measurement system to measure laser radar cross-section of the satellite was established and the scaled satellite model was measured. By analyzing the measured data and calculated data, it can be clearly seen that the BRDF of the surface materials and the laser incidence angle are two of main influential factors of the scaled satellite’s laser radar cross-section. These works can provide a reference for design of the lidar system.
Źródło:
Optica Applicata; 2017, 47, 4; 521-532
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of heating uniformity in radio frequency heating systems using carrot and radish
Autorzy:
Kong, L.
Min, Z.
Wang, Y.
Adhikari, B.
Yang, Z.
Powiązania:
https://bibliotekanauki.pl/articles/25929.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Opis:
Lack of heating uniformity is a major problem impeding the broader adaptation of radio frequency heaters in industrial applications. The overall aim of this study was to evaluate the uniformity of heating or temperature distribution within food samples (three different carrot and one radish rectangles) placed vertically and horizontally within a radio frequency heating cavity. The intensity of the electric field in radio frequency was found to be symmetrical. The temperatures at the vertically top positions were lower than the vertically bottom positions at the equidistance from the vertical center with the highest was at the vertically central position. The rate of temperature rise at all the positions were higher in taller (higher mass) than the shorter (lower mass) rectangles of carrots. The temperatures at the corners and edges were lower than at the cross sectionally central positions at all the heights tested in both carrots and radishes. The rate of temperature rise at all the vertical positions was higher in radish rectangles than in the carrot rectangles of the same dimensions. The similarity of temperature distribution in carrot and radish rectangles suggested that the heating patterns and uniformity in carrots and radishes in RF heating were almost the same.
Źródło:
International Agrophysics; 2016, 30, 4
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of flotation behavior and mechanism of cervantite activation by copper ions
Autorzy:
Wang, J.
Wang, Y.
Fu, K.
Xu, L.
Wang, Z.
Sun, H.
Xiao, J.
Powiązania:
https://bibliotekanauki.pl/articles/110228.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation
cervantite
copper ions
activation mechanism
Opis:
Copper-ion activation plays a highly important role in cervantite (Sb2O4) flotation. Without metal-ion activation, cervantite cannot be floated by sodium oleate. In this study, flotation tests were conducted to study the effect of Cu2+ on the flotation behaviours of cervantite and quartz (SiO2) as the main gangue mineral. Metal-ion adsorption capacities, zeta potentials, solution chemistry and X-ray photoelectron spectra were analyzed to study the adsorption behavior and mechanism of copper ions and sodium oleate interaction with the minerals surfaces. The results demonstrate that under weakly acidic conditions, cervantite can be flotated and separated from quartz by the addition of copper ions. The reason is that copper ions can be selectively adsorbed on the cervantite surface under weakly acidic conditions, thereby promoting the adsorption of sodium oleate onto the cervantite surface by chemical adsorption. Conversely, copper ions are weakly adsorbed on quartz surfaces below pH 6.1, and sodium oleate cannot be adsorbed on quartz surfaces by chemical adsorption. The hydroxy copper species are integral to the selective activation of cervantite over quartz.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 814-825
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fully-phase optical image encryption in diffractive-imaging scheme with QR-code-based random illumination
Autorzy:
Wang, Z.
Zhang, Y.
Gong, Q.
Li, S.
Qin, Y.
Powiązania:
https://bibliotekanauki.pl/articles/174126.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
optical encryption
diffractive imaging
fully phase
phase retrieval algorithm
Opis:
Based on a fully phase encoding and phase retrieval algorithm, a diffractive-imaging-based optical encryption scheme with random illumination is proposed. In the encryption process, a QR code image is placed in the optic path to modulate the incident light and thus generate a random illumination, which has been demonstrated to enable the proposed scheme to resist the multi-slice ptychographic phase retrieval algorithm attack. The plaintext is phase-encoded, and then encrypted by two random phase masks. The diffraction pattern in the output plane is recorded as ciphertext by a CCD camera. For decryption, an iterative phase retrieval algorithm with median filtering operation is implemented. Simulation results demonstrate the effectiveness, security, and robustness of the proposal.
Źródło:
Optica Applicata; 2017, 47, 2; 233-243
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The endomycorrhizal fungal species and their effects on the growth and nutrient characteristics of Eucalyptus maidenii seedlings in China
Autorzy:
Wang, X.
Kong, X.
Zhao, Y.
Cao, Y.
Cao, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2077654.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Eucalyptus maidenii
endomycorrhizal fungi
major species
Opis:
Eucalyptus maidenii plantations are typically fertilized to increase the yields of eucalyptus oil and timber. However, the application of chemical fertilizers is costly and can cause environmental pollution and soil erosion. Mycorrhiza fungi can facilitate the cultivation of optimal seedlings while promoting the growth of trees. To date, investigations into the inoculation of endomycorrhizal fungi to enhance the productivity of E. maidenii in Yunnan, China have not been undertaken. The species/dominant species of endomycorrhizal fungi on E. maidenii in Yunnan were isolated and iden- tified. The effect of endomycorrhizal fungi on E. maidenii was elucidated. The major species of endomycor- rhizal fungi that affect E. maidenii were ascertained. Bulk soil was collected from an E. maidenii plantation, and the species of endomycorrhizal fungi were inves- tigated. The effect of the endomycorrhizal fungi on E. maidenii were analyzed via a single factor experimental design, where the number of spores of endomycorrhizal fungi in the seedling substrate were controlled. The major endomycorrhizal fungi species that affected E. maidenii were ascertained via stepwise regression analysis. Five endomycorrhizal fungal species were isolated from the bulk soil, with the dominant being Glomus ag- gregatum and Glomus mosseae. With higher counts of endomycorrhizal fungal spores in the seedling substrate, the infection rate and intensity of seedlings were observed to increase, as well as the NPK concentrations of the bulk soil. With the increased nitrogen concentration in the bulk soil, the nitrogen concentration of the aerial components of the seedlings also increased. The NPK concentrations in the bulk soil and seedlings, the second order lateral roots, the root activity, and the seedling height were significantly promoted by the presence of endomycorrhizal fungi (the third experimental treatment). The NPK concentrations of the bulk soil and seedlings, as well as the growth indices of seedlings increased through endomycorrhizal fungi inoculation. The major species of the endomycorrhizal fungi on E. maidenii were G. aggregatum, Glomus multicaule, and Claroideoglomus etunicatum.
Źródło:
Dendrobiology; 2020, 83; 68-74
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental research on energy release characteristics of water-bearing sandstone alongshore wharf
Autorzy:
Wang, S.
Zhao, Y.
Zou, Z.
Jia, H.
Powiązania:
https://bibliotekanauki.pl/articles/258604.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
sandstone
energy release
water content
confining pressure
Opis:
It is important to evaluate the deformation and failure of sandstone in the foundation engineering of coast, river bank and lake shore. While the deformation and failure of sandstone is a comprehensive result of energy release and dissipation, and energy release is the internal reason which leads to global failure of the sandstone. The experimental analysis is conducted on the character of energy revolution of the sandstone specimen by rating loading and unloading, and the catastrophe model is followed in analyzing elastic strain energy accumulation and release in rock deformation and failure. The index based on elastic energy release is proposed to assess the rock brittleness. It is found that increasing water content is to relieve energy release and catastrophe failure of the rock specimen, and weakening the capacity of elastic energy storage. The peak and residual values of elastic energy are raised as the confining pressure increases, and the post-peak released energy decreases progressively. The confining pressure strengthens energy storage and inhibits energy release of the rock specimen, and saturation of rock will weaken this inhibit effect. The brittleness index decreases with increasing confining pressure as the rock specimen transforming from brittle to ductile.
Źródło:
Polish Maritime Research; 2017, S 2; 147-153
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of ship’s trajectory planning in collision situations by hybrid genetic algorithm
Autorzy:
Ni, S.
Liu, Z.
Cai, Y.
Wang, X.
Powiązania:
https://bibliotekanauki.pl/articles/259640.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
trajectory planning
Multiple Genetic Algorithm
ship collision avoidance
nonlinear programming
COLREGs
Opis:
Ship collision-avoidance trajectory planning aims at searching for a theoretical safe-critical trajectory in accordance with COLREGs and good seamanship. In this paper, a novel optimal trajectory planning based on hybrid genetic algorithm is presented for ship collision avoidance in the open sea. The proposed formulation is established based on the theory of the Multiple Genetic Algorithm (MPGA) and Nonlinear Programming, which not only overcomes the inherent deficiency of the Genetic Algorithm (GA) for premature convergence, but also guarantees the practicality and consistency of the optimal trajectory. Meanwhile, the encounter type as well as the obligation of collision avoidance is determined according to COLREGs, which is then considered as the restricted condition for the operation of population initialization. Finally, this trajectory planning model is evaluated with a set of test cases simulating various traffic scenarios to demonstrate the feasibility and superiority of the optimal trajectory.
Źródło:
Polish Maritime Research; 2018, 3; 14-25
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Improved Robust Kalman Filter in Data Fusion for PPP/INS Tightly Coupled Positioning System
Autorzy:
Li, Z.
Yao, Y.
Wang, J.
Gao, J.
Powiązania:
https://bibliotekanauki.pl/articles/221374.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
PPP/INS tightly coupled positioning
robust filter
IGG scheme
Mahalanobis distance
Opis:
A robust Kalman filter improved with IGG (Institute of Geodesy and Geophysics) scheme is proposed and used to resist the harmful effect of gross error from GPS observation in PPP/INS (precise point positioning/inertial navigation system) tightly coupled positioning. A new robust filter factor is constructed as a three-section function to increase the computational efficiency based on the IGG principle. The results of simulation analysis show that the robust Kalman filter with IGG scheme is able to reduce the filter iteration number and increase efficiency. The effectiveness of new robust filter is demonstrated by a real experiment. The results support our conclusion that the improved robust Kalman filter with IGG scheme used in PPP/INS tightly coupled positioning is able to remove the ill effect of gross error in GPS pseudorange observation. It clearly illustrates that the improved robust Kalman filter is very effective, and all simulated gross errors added to GPS pseudorange observation are successfully detected and modified.
Źródło:
Metrology and Measurement Systems; 2017, 24, 2; 289-301
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preventive maintenance strategy optimizing model under two-dimensional warranty policy
Model optymalizacji strategii konserwacji zapobiegawczej w warunkach dwuwymiarowej polityki gwarancyjnej
Autorzy:
Cheng, Z. H.
Yang, Z. Y.
Zhao, J. M.
Wang, Y. B.
Li, Z. W.
Powiązania:
https://bibliotekanauki.pl/articles/302023.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
two-dimensional warranty
imperfect preventive maintenance
availability
gwarancja dwuwymiarowa
niepełna konserwacja zapobiegawcza
dyspozycyjność
Opis:
An effective warranty servicing strategy should be made considering both warranty cost and product availability. Based on the two-dimensional free repair warranty, a strategy combining the imperfect preventive maintenance and minimal repair is proposed where the imperfect preventive maintenances are implemented in a special subregion of the warranty and all other failures are repaired minimally. By modeling the warranty cost and product availability, we derive the optimum warranty servicing strategy and corresponding parameters to minimize the cost-effective of unit time. Finally, we provide a numerical illustration and a comparison with some other strategies.
Efektywna strategia obsługi gwarancyjnej powinna uwzględniać zarówno koszty gwarancji jak i dyspozycyjność produktu. W oparciu o pojęcie dwuwymiarowej gwarancji bezpłatnej naprawy, zaproponowano strategię łączącą niepełną konserwację zapobiegawczą z naprawą minimalną, gdzie działania obsługowe w ramach niepełnej konserwacji zapobiegawczej przeprowadza się w ramach specjalnego podobszaru gwarancji, a wszelkie inne uszkodzenia naprawia się w ramach naprawy minimalnej. Modelując koszty naprawy oraz dyspozycyjność produktu, wyprowadzono optymalną strategię obsługi gwarancyjnej oraz odpowiadające jej parametry w celu zminimalizowania kosztów na jednostkę czasu. Na koniec, proponowane rozwiązanie zilustrowano na przykładzie numerycznym oraz porównano z innymi strategiami
Źródło:
Eksploatacja i Niezawodność; 2015, 17, 3; 365-373
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Proteomics profiles reveal the potential roles of proteins involved in chicken macrophages stimulated by Lipopolysaccharide
Autorzy:
Li, S.
Chen, Y.
Xue, W.
Wang, Q.
Huai, Z.
An, C.
Wang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/16647586.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
chicken macrophage (HD11)
immune response
lipopolysaccharide (LPS)
proteomics
Opis:
Lipopolysaccharide (LPS), a core part of gram-negative bacteria, is crucial for inducing an inflammatory response in living things. In the current study, we used LPS from Salmonella to stimulate chicken macrophages (HD11). Proteomics was used to investigate immune-related proteins and their roles further. Proteomics investigation revealed 31 differential expression proteins (DEPs) after 4 hours of LPS infection. 24 DEPs expressions were up-regulated, while seven were down-regulated. In this investigation, ten DEPs were mainly enriched in S. aureus infection, complement, and coagulation cascades, which were all implicated in the inflammatory response and clearance of foreign pathogens. Notably, complement C3 was shown to be up-regulated in all immune-related pathways, indicating that it is a potential protein in this study. This work contributes to a better understanding and clarification of the processes of Salmonella infection in chickens. It might bring up new possibilities for treating and breeding Salmonella-infected chickens.
Źródło:
Polish Journal of Veterinary Sciences; 2023, 26, 2; 265-274
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flotation separation of cervantite from quartz
Autorzy:
Wang, J.
Hua, Y.
Yu, S.
Xiao, J.
Xu, L.
Wang, Z.
Powiązania:
https://bibliotekanauki.pl/articles/110941.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
cervantite
quartz
dodecylamine
flotation
density functional theory
Opis:
Flotation separation of cervantite (Sb2O4) from quartz was investigated using dodecylamine (DDA) as a collector. Experiments were conducted on single minerals and on a synthetic mixture of quartz and cervantite. Flotation separation mechanisms were investigated using the zeta potential technique, solution chemistry principles, density functional calculations and Fourier Transform Infrared (FT-IR) spectroscopy. The results indicated that DDA, primarily in the form of molecules, exhibited excellent performance in flotation of cervantite and quartz at pH 10.5. The adsorption energy of the DDA molecules on the cervantite surface was greater than the adsorption energy of water molecules, while the adsorption energy of DDA on the quartz surface was less than the adsorption energy of water molecules. DDA molecules can be adsorbed on the quartz surface to a certain extent, but it was difficult for the same molecule to be adsorbed on the cervantite surface in the pulp. This resulted in flotation of quartz. DDA molecules were adsorbed on quartz not only through physical adsorption but also by hydrogen bonding. However, cervantite could not be floated at pH 10.5 since adsorption of DDA molecules occurred through weak physical bonds on cervantite.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 1119-1132
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza niezawodnościowa mechanicznego elementu wibracyjnego z wykorzystaniem teorii zbiorów rozmytych
Reliability analysis of mechanical vibration component using fuzzy sets theory
Autorzy:
Wu, W.
Huang, H. Z.
Wang, Z. L.
Li, Y. F.
Pang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/301605.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
analiza niezawodnościowa
drgania mechaniczne
niezawodność rozmyta
rozmyta ocena kompleksowa
reliability analysis
mechanical vibration
fuzzy reliability
fuzzy comprehensive evaluation
Opis:
Tradycyjna analiza niezawodnościowa wibracyjnego elementu mechanicznego bierze pod uwagę jedynie losowość drgań, rzadko zaś wyjaśnia mogącą występować rozmytość. Taka analiza nie odpowiada zatem praktyce inżynierskiej. Opierając się na teorii drgań mechanicznych, w niniejszym artykule zaproponowano nowatorskie podejście w ramach teorii rozmytej niezawodności, które łączy rozmytą ocenę kompleksową oraz teorię zbiorów rozmytych. Rozmytej oceny kompleksowej użyto do optymalizacji rozmytych czynników analizy niezawodnościowej elementu wibracyjnego. W celu porównania efektywności proponowanego podejścia z efektywnością podejścia tradycyjnego przedstawiono dwa przykłady z dziedziny inżynierii. Wyniki pokazują, że proponowane podejście jest lepsze od tradycyjnego ze względu na możliwość objęcia w problemach inżynierskich czynników rozmytych.
The conventional reliability analysis of mechanical vibration component only considers the randomness of vibration but rarely for the fuzziness that may exist. It is therefore difficult to be consistent with the engineering practices. Based on the mechanical vibration theory, a novel fuzzy reliability approach by integrating the fuzzy comprehensive evaluation and fuzzy set theory is proposed in this paper. The fuzzy comprehensive evaluation is used to optimize the fuzzy factors of the reliability analysis of vibration component. With the aim of comparing the performance of the proposed approach with the conventional approach, two engineering examples are presented. The results demonstrate that the proposed approach is better than the conventional approach for its capability of covering fuzzy factors in the engineering problems.
Źródło:
Eksploatacja i Niezawodność; 2012, 14, 2; 130-134
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Joint optimization of redundancy and maintenance staff allocation for multi-state series-parallel systems
Optymalizacja łączona alokacji nadmiarowości oraz alokacji pracowników służb utrzymania ruchu w wielostanowych systemach szeregowo-równoległych
Autorzy:
Liu, Y.
Huang, H. Z.
Wang, Z.
Li, Y. F.
Zhang, X. L.
Powiązania:
https://bibliotekanauki.pl/articles/301921.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
wielostanowe systemy szeregowo równoległe
zagadnienie alokacji nadmiarowości (RAP)
alokacja pracowników służb utrzymania ruchu
teoria kolejek
uniwersalna funkcja generacyjna (UFG)
algorytm świetlika (FA)
multi-state series-parallel systems
redundancy allocation problem (RAP)
maintenance staff allocation
queue theory
universal generation function (UGF)
firefly algorithm (FA)
Opis:
Multi-state system (MSS), as a kind of complex system consisting of elements with different performance levels, widely exists in engineering practices. In this paper, redundancy and maintenance staff allocation problems for repairable MSS with series-parallel configuration are considered simultaneously. The traditional redundancy allocation problem (RAP) for MSS always assumes that maintenance resources are unlimited. However in many practical situations, maintenance resources are limited due to the budget and/or time. To maximize the system availability under a certain demand, there are two feasible ways: (1) designing an optimal system configuration with available elements, and (2) allocating more maintenance staffs to reduce waiting time for repair. With the assistance of Markov queue model, the availabilities of identical version elements with the pre-assigned number of maintenance staffs can be evaluated. The universal generation function (UGF) is employed to assess the availability of entire MSS under a certain demand. Two optimization formulas considering the limited maintenance resources are proposed. One regards the limitation of maintenance resources as a constraint, and the other considers minimizing the total system cost including both the system elements and maintenance staff fees. The system redundancy and staffs allocation strategies are jointly optimized under required availability. A numerical case is presented to illustrate the efficiency of the proposed models. The Firefly Algorithm (FA), which is a recently developed metaheuristic optimization algorithm, is employed to seek the global optimal strategy.
Systemy wielostanowe (multi-state systems, MSS), stanowiące typ złożonych systemów zbudowanych z elementów o różnym poziomie wydajności, znajdują szerokie zastosowanie w praktyce inżynierskiej. W prezentowanej pracy podjęto rozważania łączące zagadnienia alokacji nadmiarowości oraz alokacji pracowników służb utrzymania ruchu w naprawialnych systemach MSS o konfiguracji szeregowo-równoległej. Tradycyjnie ujmowane zagadnienie alokacji nadmiarowości (redundancy allocation problem, RAP) w systemach MSS zawsze zakłada, że środki obsługi są nieograniczone. Jednakże w wielu sytuacjach praktycznych, środki obsługi mogą być ograniczone budżetem i/lub czasem. Istnieją dwa możliwe sposoby maksymalizacji gotowości systemu przy określonym zapotrzebowaniu użytkowników: (1) zaprojektowanie optymalnej konfiguracji systemu z wykorzystaniem dostępnych elementów oraz (2) alokowanie większej liczby pracowników obsługi w celu zmniejszenia czasu oczekiwania na naprawę. Dostępność jednakowych wersji elementów przy wcześniej określonej liczbie pracowników obsługi oceniano za pomocą modelu kolejek Markowa. Uniwersalną funkcję generacyjną (UGF) wykorzystano do oceny gotowości całego systemu MSS przy określonym zapotrzebowaniu. Zaproponowano dwa równania optymalizacyjne uwzględniające ograniczone środki obsługi. W jednym z nich ograniczoność środków obsługi potraktowano jako ograniczenie (constraint), natomiast drugie równanie dotyczyło minimalizacji całkowitych kosztów systemu włącznie z kosztami elementów systemu oraz płacą pracowników służb utrzymania ruchu. Strategie alokacji nadmiarowości systemu oraz alokacji pracowników poddano jednoczesnej optymalizacji z uwzględnieniem wymaganej gotowości. Wydajność proponowanych modeli zilustrowano przykładem numerycznym. Poszukiwania optymalnej strategii globalnej prowadzono przy pomocy niedawno opracowanego metaheurystycznego algorytmu optymalizacyjnego znanego jako algorytm świetlika (Firefly Algorithm, FA).
Źródło:
Eksploatacja i Niezawodność; 2012, 14, 4; 312-318
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intervalley Transfer of Electrons in ZnS-Type Thin Film Electroluminescent Devices
Autorzy:
Zhao, H.
Wang, Y.
Xu, Z.
Xu, X.
Powiązania:
https://bibliotekanauki.pl/articles/2011094.pdf
Data publikacji:
1999-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
72.20.-i
78.60.-b
Opis:
Based on the calculation about intervalley scattering rates in ZnS, the intervalley transfer process in ZnS-type thin film electroluminescent devices is investigated through the Monte Carlo simulation. The transient time of intervalley transfer is about 0.2-0.3 ps, it coincides with that of electron average energy. Intervalley distribution shifts to high valleys as the electric field increased. The electron kinetic energy distributions in different valleys are also gained. We propose that high valleys could store energies, which could prolong the decay of the electron average energy as the field was removed. These results could be used as the basic data on the study of electroluminescent process and the citation of valley parameters in analytic models should be carefully considered.
Źródło:
Acta Physica Polonica A; 1999, 96, 3-4; 475-482
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Metal Fibre Content of Blended Electromagnetic Shielding Fabric on Shielding Effectiveness Considering Fabric Weave
Wpływ zawartości włókien metalowych w tkaninach z przędz mieszankowych tworzących barierę elektromagnetyczną na wydajność ekranowania w zależności od splotu tkaniny
Autorzy:
Liu, Z.
Zhang, Y.
Rong, X.
Wang, X.
Powiązania:
https://bibliotekanauki.pl/articles/233107.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
fabric blended electromagnetic shielding
fabric structure
metal fibre content
shielding effectiveness
metal fibre influence
tkaniny barierowe
mieszankowe tkaniny ekranujące
struktura tkaniny
zawartość włókien metalowych
gęstość wątku i osnowy
masa liniowa przędzy
wpływ włókien metalowych
Opis:
There are few researches reported about the influence of the metal fibre content of blended electromagnetic shielding (EMS) fabric on shielding effectiveness (SE) under different fabric parameters. In order to scientifically describe the metal fibre content of blended EMS fabric considering the fabric structure, in this paper two new indicators of structure metal fibre content (SMFC) and structure equivalent thickness (SET) were constructed according to fabric structure parameters of weft and warp density, yarn density and yarn metal content. A number of experiments were designed and sixteen groups of samples prepared to explore the influence of the two indicators on the SE. Firstly the SMFC and SET of the samples were calculated by the equations of the new indicators. SE values of the samples were then tested by the waveguide method. Finally the relations between the new indicators and the SE were analysed according to experimental results and electromagnetic wave theory. Results show that the SMFC and SET can scientifically describe the metal fibre content of the blended EMS fabric. The SMFC and SET show positive growth along with the SE while other parameters remain unchanged. For the basic weave, SE values are an approximate equivalence as long as the total densities are the same as the yarn density and fibre content of the yarns is the same. As the SMFC is consistent, the more floats, the lower the SE. The research in this paper can provide an important reference for the design, testing and production of blended EMS fabric.
Niewiele publikacji opisuje wpływ zawartości włókien metalowych w mieszankowych tkaninach ekranujących przed wpływem promieniowania elektromagnetycznego na wydajność ekranowania w zależności od parametrów tkaniny. W celu naukowego opisu wpływu zawartości włókien metalowych na zdolność ekranowania w zależności od struktury tkaniny zaproponowano dwa nowe współczynniki SMFC (zależny od struktury) i SET (strukturalny ekwiwalent grubości). Współczynniki oblicza się uwzględniając parametry strukturalne m. in. takie jak gęstość wątku i osnowy, masę liniową przędzy i ilość włókien metalowych. Zaprojektowano serię eksperymentów i zaproponowano 16 grup próbek tak zaprojektowanych, aby można było zbadać wpływ parametrów na dwa nowo zaproponowane współczynniki. Wartości współczynników zostały obliczone, a zdolność ekranowania próbek pomierzona w specjalnym urządzeniu badawczym. Analiza wyników pokazała, że nowo zaproponowane współczynniki mogą charakteryzować wielkość tłumienia w zależności od zastosowanej ilości włókien metalowych. Stwierdzono wyraźne zależności tłumienia od stosowanych częstotliwości. Uzyskane wyniki mogą stanowić podstawę dla projektowania, sprawdzania i produkcji tkanin barierowych dla promieniowania elektromagnetycznego.
Źródło:
Fibres & Textiles in Eastern Europe; 2015, 4 (112); 83-87
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative investigations of nonlinear and linear observers for a highly manoeuvrable target in sliding mode guidance
Autorzy:
Wang, Y.
Sun, M.
Du, S.
Chen, Z.
Powiązania:
https://bibliotekanauki.pl/articles/201020.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
guidance law
second-order sliding mode
super-twisting algorithm
linear observer
target manoeuvre
algorytm
obserwator liniowy
manewr
algorytm przesuwania
Opis:
Target manoeuvre is one of the key factors affecting guidance accuracy. To intercept highly maneuverable targets, a second-order sliding-mode guidance law, which is based on the super-twisting algorithm, is designed without depending on any information about the target motion. In the designed guidance system, the target estimator plays an essential role. Besides the existing higher-order sliding-mode observer (HOSMO), a first-order linear observer (FOLO) is also proposed to estimate the target manoeuvre, and this is the major contribution of this paper. The closed-loop guidance system can be guaranteed to be uniformly ultimately bounded (UUB) in the presence of the FOLO. The comparative simulations are carried out to investigate the overall performance resulting from these two categories of observers. The results show that the guidance law with the proposed linear observer can achieve better comprehensive criteria for the amplitude of normalised acceleration and elevator deflection requirements. The reasons for the different levels of performance of these two observer-based methods are thoroughly investigated.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2017, 65, 2; 233-245
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular phylogeny of Populus (Salicaceae, Salicales) with focus on inter- and intrasectional relationships
Autorzy:
Du, S.
Hu, X.
Yang, Y.
Wang, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2130215.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
molecular phylogeny
section Populus
section Tacamahaca
section Aigeiros
Opis:
The relationships among sections and species within each section in the genus Populus have attracted much attention from taxonomists and biologists. In this paper, we provide an overview of the current state of Populus phylogenetics and discuss the origin of some hybrid species. There has been some controversy surrounding the origin of the genus Populus in North America and subsequent dispersal and differentiation in other parts of the world. We present the most plausible scenario based on phylogenetic analysis and fossil records. Sections Abaso, Turanga and Populus are all monophyletic, whereas sections Aigeiros, Tacamahaca and Leucoidesshow some degree of polyphyly. Sections Abaso and Turanga are relatively primitive lineages in Populus. With the accumulation of sequencing data and new analytical tools, it will be possible to investigate more complicated issues concerning genus Populus within a phylogenetic framework.
Źródło:
Dendrobiology; 2022, 88; 56-69
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical image encryption by using diffractive imaging with special constraint in the input plane
Autorzy:
Wang, Z.
Wang, H.
Yang, X.
Zhang, P.
Hou, C.
Qin, Y.
Powiązania:
https://bibliotekanauki.pl/articles/173781.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
optical encryption
diffractive imaging
bilinear interpolation
Opis:
In order to simplify the optical setup and the encryption process, a diffractive-imaging-based optical encryption system using a single diffraction pattern is proposed. A predesigned binary mask is placed before the plaintext in the encryption process, and three randomly distributed phase only masks are placed in the optical path. Only one diffraction pattern needs to be recorded as ciphertext by CCD. In the decryption process, an iterative phase retrieval algorithm is applied, in which the predesigned binary mask acts as a support constraint in the input plane. After the iterative process, an interpolation operation for the zero-valued pixels is also implemented. The effectiveness and robustness of the proposal are demonstrated by numerical simulation results.
Źródło:
Optica Applicata; 2016, 46, 1; 57-69
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Review of the Photodecomposition of Some Important Energetic Materials
Autorzy:
Sun, Y.
Shu, Y.
Xu, T.
Shui, M.
Zhao, Z.
Gu, Y.
Wang, X.
Powiązania:
https://bibliotekanauki.pl/articles/358397.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
photodecomposition mechanisms
energetic materials
Opis:
The photodecomposition mechanisms of energetic materials vary with molecular structure, photodissociation wavelength, the phase of the material, experimental pressure and temperature etc. In this paper, the significant progress on photodecomposition studies of some important energetic materials achieved in recent years is introduced in detail, including nitromethane, DMNA (dimethylnitramine), TATB (1,3,5-triamino-2,4,6-trinitrobenzene), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), HMX (1,3,5,7-tetranitro-1,3,5,7- tetrazacycloctane) and CL-20 (2,4,6,8,10,12-hexanitrohexaazaisowurtzitane). The difficulties and prospects of photodecomposition research of energetic materials are also indicated.
Źródło:
Central European Journal of Energetic Materials; 2012, 9, 4; 411-423
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of recent coastline evolution due to marine reclamation projects in the Qinzhou Bay
Autorzy:
Yan, Y.
Zhang, Z.
Wang, C.
Zhang, L.
Huang, Y.
Zhang, J.
Powiązania:
https://bibliotekanauki.pl/articles/258862.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
Qinzhou Bay
marine reclamation
remote sensing
geospatial analysis
coastline evolution
Opis:
Intense marine reclamation activities bring obvious benefits, meanwhile, these activities also influence the coastal natural formation, hydrodynamic processes and water environment etc. In order to investigate the exact influence in the Qinzhou Bay brought by marine reclamation behaviors in recent years, based on the remote sensing image data in the Qinzhou Bay in 2006, 2008, 2009, 2012 and 2014, with the help of GIS and RS software, the thesis interprets Qinzhou Bay coastline and artificial reclamation by man-machine interaction and makes quantitative analysis in the Qinzhou Bay coast evolution recently. The results show: (1) Qinzhou Bay coastal morphology change degree was strong in 2006 - 2012 and the coastline changed greatly. Originally part of the natural shore segments which had twists and turns were gradually filled into artificial coast, the coast constantly advanced to the sea, coastline became regular and straight; (2) The change degree of coastline was relatively small in 2006-2008, the average artificial coastline increased 8.86 km/a, the average artificial reclamation area was 20.79 km2 /a; in 2008-2012, the change range of coastline was the greatest, coastline changed most severely, the average artificial coastline increased 16.07 km/a, the average artificial reclamation area was 58.52 km2 /a; however, in 2012-2014, coastline change degree relatively slowed, the average artificial coastline increased 4.04 km per year, the average artificial reclamation area was 3.464 km2 /a. (3) Compared to the studies of predecessors, the innovation of this paper is that it is the first to carry out the detailed research on coastline evolution caused by reclamation engineerings of the Qinzhou Bay, then formed the change results on coastline that caused by intense human activities in the Qinzhou Bay, provided the area of the marine environment protection with full and accurate data.
Źródło:
Polish Maritime Research; 2017, S 2; 188-194
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of overlying water pH, dissolved oxygen and temperature on heavy metal release from river sediments under laboratory conditions
Autorzy:
Huang, Y.
Zhang, D.
Xu, Z.
Yuan, S.
Li, Y.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/204852.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
heavy metal
release
river sediment
Opis:
The heavy metal release experiments were conducted in the laboratory to examine the effects of 3 factors - pH, dissolved oxygen (DO), and temperature on the metal release from sediments taken from the Huangpu River. The metal concentrations in the dry sediments ranged from 0.030 to 0.296 mg g-1 for Cr, 0.021 to 0.097 mg g-1 for Ni, 0.014 to 0.219 mg g-1 for Cu, 0.035 mg to 0.521 mg g-1 for Zn, 0.0002 to 0.001 mg g-1 for Cd and 0.023 to 0.089 mg g-1 for Pb. Most of the metals found in the sediments were in the form of residual fraction, the exchangeable fraction consisted of only a small portion of total metals. The average dissolved metal concentrations in the overlying water during the 13-day period under different conditions were ranging from 0.82 to 1.93 μg L-1 for Cr, 1.08 to 4.19 μg L-1 for Ni, 40.79 to 82.28 μg L-1 for Cu, 20.30 to 29.96 μg L-1 for Zn, 1.57 to 4.07 μg L-1 for Cd, and 22.26 to 75.50 μg L-1 for Pb, respectively. Statistical interpretation of the data indicated that pH (7, 8, 9), dissolved oxygen DO (1.0 and 5.0 mg L-1) and temperature (4, 16, 25°C) had no significant effects on the heavy metal release under the studied conditions. Cu and Pb had the highest release flux, while Cd, Pb and Cu had higher mobility. The main factors controlling the metals release might be the inherent characters of metals and sediments.
Źródło:
Archives of Environmental Protection; 2017, 43, 2; 28-36
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polarization properties of Gaussian–Schell model quantization field in a turbulent marine-atmosphere
Autorzy:
Zhao, Y.
Xia, M.
Wang, Q.
Li, Y.
Hu, Z.
Sun, H.
Zhang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/173639.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
polarization fluctuation
Gaussian–Schell model
marine-atmosphere
Kolmogorov turbulence
Opis:
Polarization properties of Gaussian–Schell model quantization field propagating through the Kolmogorov turbulence of a marine-atmosphere channel are studied based on the degree of quantum polarization. The effective photon annihilation and creation operators of Gaussian–Schell model quantization field propagation in a marine-atmosphere are developed by making use of the extended Huygens–Fresnel integral of quantum field. The effects of the outer scale on the degree of polarization can be neglected. As the source transverse coherent width, the number of received photons, the inner scale of turbulent eddies, and the source transverse radius decrease or the re- fractive index structure parameter increases, the degree of polarization decreases. In theory, we find that the polarization fade of marine-atmosphere turbulence channels is larger than that of terrene-atmosphere turbulence channels under same transport parameters and the channel with a stronger turbulence strength will possess a larger detection area of a polarization signal, which have potentially important implications for free-space quantum key distribution.
Źródło:
Optica Applicata; 2016, 46, 3; 335-345
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Property of 1,4-Diamino-3,6- dinitropyrazolo[4,3-c]pyrazole and Its Derivatives
Autorzy:
Li, Y.-N.
Wang, B.-Z.
Shu, Y.-J.
Zhang, S.-Y.
Lian, P.
Powiązania:
https://bibliotekanauki.pl/articles/358674.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
3,6-dinitropyrazolo[4,3-c]pyrazole (DNPP)
1,4-diamino-3,6- dinitropyrazolo[4,3-c]pyrazole (DADNP)
4,4’-(triaz-1-ene-1,3-diyl)bis(1- amine-3,6-dinitropyrazolo[4,3-c]pyrazole) (TBADNP)
N-amination reaction
synthesis
property
Opis:
A synthetic procedure has been developed for the synthesis of 1,4-diamino- 3,6-dinitropyrazolo[4,3-c]pyrazole (DADNP) via N-amination reaction. Its derivatives, 4,4’-(triaz-1-ene-1,3-diyl)bis(1-amine-3,6-dinitropyrazolo[4,3-c] pyrazole) (TBADNP) and 1,4-dinitramino-3,6-dinitropyrazolo[4,3-c]pyrazole (DNADNP), were first designed and synthesized by the diazotization and nitrification of amino group, and their structures were characterized by IR, 1H NMR, 13C NMR, elementary analysis and MS. The thermal properties of target compounds were studied by means of differential scanning calorimetry (DSC) and thermogravimetry (TG). The thermal decomposition peak temperatures of DADNP, TBADNP and DNADNP are 227, 236 and 288 °C, respectively. Results show that the derivatives of 1,4-diamino-3,6-dinitropyrazolo[4,3-c]pyrazole have better thermal stability.
Źródło:
Central European Journal of Energetic Materials; 2016, 13, 2; 321-331
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seroprevalence of antibodies to classical swine fever virus and porcine reproductive and respiratory syndrome virus in healthy pigs in Hunan Province, China
Autorzy:
Yu, H.
Zhang, L.
Cai, Y.
Hao, Z.
Luo, Z.
Peng, T.
Liu, L.
Wang, N.
Wang, G.
Deng, Z.
Zhan, Y.
Powiązania:
https://bibliotekanauki.pl/articles/16539345.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
classical swine fever virus (CSFV)
porcine reproductive and respiratory syndrome virus (PRRSV)
pig
seroprevalence
antibody
Opis:
Classical swine fever (CSF) and porcine reproductive and respiratory syndrome (PRRS) are responsible for major economic losses and represent a threat to the swine industry worldwide. Routine surveillance serology for CSF and PRRS viruses is critical to maintaining the health status of sow farms in Hunan Province, which is one of the top pig production provinces in China. The aim of our study was to investigate the serological statistics of CSF virus (CSFV) and PRRS virus (PRRSV) in Hunan Province. The cohort serum samples were collected from vaccinated and unvaccinated pigs. Our findings showed that the average rates of CSFV and PRRSV antibody seropositivity were 82.2% (95% CI: 80.1-84.3) and 84.8% (95% CI: 82.5-87.1), respectively, in the immunized group and that these rates were higher than those in the unvaccinated group (58.6% for CSFV and 47.8% for PRRSV). Additionally, the level of CSFV antibody in piglet serum declined gradually with age, whereas PRRSV-specific antibody level increased initially (1 to 2 weeks old) and then declined with age (2 to 4 weeks old). In summary, we investigated the difference in CSFV/PRRSV antibody levels among piglets at various weeks old (1 to 4 weeks) to further establish the duration of maternal immunity in piglets. In addition, routine monitoring of CSFV/PRRSV antibodies in immunized pigs was carried out to evaluate the efficacy of vaccination.
Źródło:
Polish Journal of Veterinary Sciences; 2022, 25, 3; 375-381
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on Ships Safety Control System
Autorzy:
Han, X. J.
Meng, X. Y.
Wang, Z. W.
Powiązania:
https://bibliotekanauki.pl/articles/117442.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
Safety of Navigation
ships safety
Control System
Ships Safety Control System
Ship Accidents
Human Factor
Control Strategy
Accident Precaution
Opis:
The proportion of main reasons of ships accidents to the whole reasons is discussed in the paper. Among these reasons, human factors are in the majority. So a method to prevent wrong orders sent by a navigator is laid emphasis on. On the basis of this, a ships safety control system is studied. The construction and control principle of the ships safety control system, as well as control strategy, implementation method and key technology are elaborated in the paper.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2009, 3, 1; 19-22
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Convex sublattice based reliability theory
Teoria niezawodności oparta na pojęciu podkraty wypukłej
Autorzy:
Pang, Y.
Huang, H. Z.
He, L.
Wang, Z.
Xiao, N. C.
Powiązania:
https://bibliotekanauki.pl/articles/301375.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
relacja kongruencji
podkrata wypukła
teoria krat
wielostanowa funkcja struktury
teoria możliwości
górny kres zbioru
congruence relation
convex sublattice
lattice theory
multistate structure function
possibility theory
upper bound set
Opis:
Classical probability theory has been widely used in reliability analysis; however, it is hard to handle when the system is lack of` adequate and sufficient data. Nowadays, alternative approaches such as possibility theory and fuzzy set theory have also been proposed to analyze vagueness and epistemic uncertainty regarding reliability aspects of complex and large systems. The model presented in this paper is based upon possibility theory and multistate assumption. Convex sublattice is addressed on congruence relation regarding the complete lattice of structure functions. The relations between the equivalence classes on the congruence relation and the set of all structure functions are established. Furthermore, important reliability bounds can be derived under the notion of convex sublattice. Finally, a numerical example is given to illustrate the results.
Klasyczna teoria prawdopodobieństwa ma szerokie zastosowanie w analizie niezawodności, jednak trudno jest się nią posługiwać, kiedy brak jest wystarczających i odpowiednich danych na temat systemu. Obecnie, proponuje się alternatywne podejścia, takie jak teoria możliwości czy teoria zbiorów rozmytych, za pomocą których można analizować niepewność epistemiczną oraz nieostrość w odniesieniu do aspektów niezawodności złożonych i dużych systemów. Model przedstawiony w niniejszym artykule oparto na teorii możliwości oraz na założeniu wielostanowości. Podkratę wklęsłą opisano na relacji kongruencji, odnoszącej się do całej kraty funkcji struktury. Ustalono relacje pomiędzy klasami równoważności na relacji kongruencji a zbiorem wszystkich funkcji struktury. Ponadto posługując się pojęciem podkraty wypukłej można wyprowadzać istotne kresy niezawodności. Wyniki zilustrowano przykładem numerycznym.
Źródło:
Eksploatacja i Niezawodność; 2011, 3; 56-61
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
One step purification of impurities in the leachate of weathered crust elution-deposited rare earth ores
Autorzy:
Zhou, F.
Feng, J.
Wang, Z.
Xu, Y.
Zhang, Z.
Chi, R.
Powiązania:
https://bibliotekanauki.pl/articles/110333.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
leachate
weathered crust
rare earth ore
leachate purification
precipitation
Opis:
It is necessary to control and reduce the high content of Al3+, Cu2+ and Pb2+ ions in the leachate of weathered crust elution-deposited rare earth ore to facilitate the rare earth recovery and the quality of rare earth products. Neither NH4HCO3 nor Na2S are suitable for removal of all impurity ions and meanwhile maintain high rare earth recovery. Conventionally, NH4HCO3 is firstly adopted to remove Al3+, and then Cu2+ and Pb2+ are removed by using Na2S. This two steps purification process is quite long and results in lots of complication in operation. In this paper, a one-step purification by using the compound of NH4HCO3 and Na2S was proposed to remove Al3+, Cu2+ and Pb2+. The results showed that after purification 89% Cu, 92% Pb and 74% Al were removed from the leachate solution by using 0.1 M compound of NH4HCO3/Na2S, while maintaining 89% rare earth. The optimal purification parameters were: volume ratio of NH4HCO3 to Na2S of 9:1, volume ratio of compound to leachate of 0.05:1, precipitation time of 30 min.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 1188-1199
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantitative processing of situation awareness for autonomous ships navigation
Autorzy:
Zhou, X. Y.
Liu, Z. J.
Wu, Z. L.
Wang, F. W.
Powiązania:
https://bibliotekanauki.pl/articles/117424.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
autonomous vessel
autonomous ship
autonomous ships navigation
situation awareness (SA)
quantitative processing
navigation safety
remotely controlled vessel
maritime unmanned navigation through intelligence in networks (MUNIN)
Opis:
The first ever attempt at fully autonomous dock-to-dock operation has been tested and demonstrated successfully at the end of 2018. The revolutionary shift is feared to have a negative impact on the safety of navigation and the getting of real-time situation awareness. Especially, the centralized context onboard could be changed to a distributed context. In navigation safety domain, monitoring, control, assessment of dangerous situations, support of operators of decision-making support system should be implemented in real time. In the context of autonomous ships, decision-making processes will play an important role under such ocean autonomy, therefore the same technologies should consist of adequate system intelligence. At the same time, situation awareness is the key element of the decision-making processes. Although there is substantial research on situation awareness measurement techniques, they are not suitable to directly execute quantitative processing for the situation awareness of autonomous ships navigation. Hence, a novel quantitative model of situation awareness is firstly proposed based on the system safety control structure of remotely controlled vessel. The data source is greatly limited, but the main result still indicates that the probability of operator lose adequate situation awareness of the autonomous ship is significantly higher than the conventional ship. Finally, the paper provides a probabilistic theory and model for high-level abstractions of situation awareness to guide future evaluation of the navigation safety of autonomous ships.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2019, 13, 1; 25-31
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational Investigation on the Structure and Performance of Novel 4,7-dinitro-furazano-[3,4-d]-pyridazine Derivatives
Autorzy:
Wang, K.
Shu, Y.
Liu, N.
Ding, X.
Wu, Z.
Lu, Y.
Powiązania:
https://bibliotekanauki.pl/articles/358090.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
4,7-dinitro-furazano-[3,4-d]-pyridazine
heat of formation
density
detonation performance
bond dissociation energy
Opis:
Seven novel energetic 4,7-dinitro-furazano-[3,4-d]-pyridazine derivatives were designed, and their optimized structures and performances were studied by density functional theory (DFT) at B3LYP/6-311g(d,p) level. The detonation performances were estimated by the Kamlet-Jacobs equations. The results show that these compounds have high crystal densities (1.818-1.925 g·cm−3), detonation velocities (8.51-9.56 km·s−1) and detonation pressures (32.28-41.70 GPa). The bond dissociation energies (BDEs) of the weakest bond (N–O bond) vary from 70.889 kJ·mol−1 to 173.283 kJ·mol−1, and some of them exhibit higher BDEs than that of RDX (N–NO2 bond, 149.654 kJ·mol−1) and HMX (N–NO2 bond, 154.905 kJ·mol−1). M4 and M5 exhibit similar and higher detonation performance than RDX (8.81 km·s−1, 34.47 GPa). The detonation performance of M7 (9.56 km·s−1, 41.70 GPa) even surpasses that of HMX (9.10 km·s−1, 39.00 GPa). Otherwise, the specific impulse values of M1-M7 (266-279 s) outperform HMX (266 s) by 0-13 s, which indicates that M1-M7 may show better performance as monopropellants. It is concluded that density, heat of formation, stability, detonation performance and specific impulse of the designed compounds depend on the position and number of the N→O oxidation bonds.
Źródło:
Central European Journal of Energetic Materials; 2017, 14, 1; 26-46
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
System and Method for Simultaneous Measurement of Nitrogen Content and Uniformity of Nitration of Nitrocellulose
Autorzy:
Liu, Y.
Shao, Z.
Wang, W.
Li, W.
Lv, Y.
Sun, J.
Powiązania:
https://bibliotekanauki.pl/articles/358714.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
nitrocellulose
uniformity of nitration
nitrogen content
mixed acid nitration
cotton maturity
Opis:
Nitrocellulose (NC) is a common, commercially available, cellulosederived material and has been functionalized and widely applied in microfluidic technology, immunoassays and biochemical analyses. However, existing testing parameters always fail to completely and accurately reflect its inherent quality. In this study, we have designed and assembled a novel automatic polarizing microscope test system (PMTS) to scientifically test the nitrogen content and uniformity of nitration of NC based on the chromogenic principle of a polarization microscope. The advantages of this system are: (i) the PMTS requires less sample (only a few micrograms); (ii) the test period is shorter and the results can be obtained within 20 min; (iii) the method belongs to the nondestructive testing group, and the NC sample is not burned, dissolved, or damaged; and (iv) this method has increased accuracy, and the deviation of the nitrogen content is less than ±0.05%. The properties of various NC samples prepared by different nitricsulfuric acid systems from raw materials with diverse maturities were determined via PMTS. Five NC samples with different nitrogen contents (10.9%, 11.5%, 11.8%, 12.6% and 13.5%) were tested, and the variance of the corresponding uniformity of nitration of these samples were 3.17, 1.61, 1.15, 1.76, and 2.83. The uniformity of nitration initially decreased and then increased with increasing nitrogen content, and the best uniformity of nitration appeared at a nitrogen content of 12%. We also found that fibre maturity has a positive effect on the uniformity of nitration. This testing device and method, with its cost-effectiveness and field-portability, can significantly improve the accuracy of nitration content and uniformity, and has an important value in practical applications.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 4; 554-571
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Crystallization Process of $Fe_{75}Co_5Zr_{10}B_{10}$ Amorphous Alloy
Autorzy:
Sun, Y.
Zuo, B.
Wang, D.
Meng, X.
Liu, J.
Wang, L.
Hua, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1399278.pdf
Data publikacji:
2013-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.43.Dq
64.60.My
Opis:
$Fe_{75}Co_5Zr_{10}B_{10}$ amorphous alloy prepared by melt-spinning was annealed at various temperatures. The thermal property and microstructures were investigated by differential thermal analysis, X-ray diffraction, and transmission electron microscopy. The crystallization process of $Fe_{75}Co_5Zr_{10}B_{10}$ amorphous alloy is complex. The α-Fe phase precipitates from the amorphous matrix in the initial stage of crystallization. The α-Mn type (χ) phase precipitates at 570°C, but transforms to α-Fe phase and the Laves C14(λ) phase at higher temperature. In the final stage of crystallization, $Fe_3Zr$, $Fe_2Zr$, and unknown phases are observed and the λ-phase disappears. The α-Fe phase preferentially nucleates after annealing at 530C for 10 min and the χ-phase preferentially nucleates after annealing at 600C for 10 min. The nucleation barrier of χ-phase is larger than that of α-Fe phase. The local structure of χ-phase is more similar to amorphous phase.
Źródło:
Acta Physica Polonica A; 2013, 124, 4; 685-687
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel logic-based approach for failure modes mitigation control and quantitative system reliability analyses
Oryginalna, oparta na logice metoda kontroli ograniczania przyczyn uszkodzeń i ilościowej analizy niezawodności systemu
Autorzy:
Yang, D.
Ren, Y.
Wang, Z.
Liu, L.
Sun, B.
Powiązania:
https://bibliotekanauki.pl/articles/301303.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
failure
reliability
failure mitigation control
quantitative reliability analyses
uszkodzenie
niezawodność
kontrola ograniczania uszkodzeń
ilościowe analizy niezawodności
Opis:
The core idea of reliability design is to mitigate the product’s failure modes. However, for the cross-links among potential failure modes of a complex product, it is very difficult to establish the mapping relationship between failure modes mitigation and quantitative values of reliability, and the decision of failure modes mitigation have to be performed by virtue of experience, which always increase design period. In order to solve these problems, a novel logic-based approach for failure modes mitigation control and quantitative system reliability analyses is provided. Firstly, a hybrid of active and passive control process of reliability design is proposed. Secondly, a novel concept of failure modes correlation set (FMCS) and a determination approach based on deductive theory are presented. According to the changes in failure modes probabilities of occurrence, the reliability formulas of the components and assemblies are provided to depict the effects of failure mode mitigation on reliability of components and assemblies. And then the FMCS mitigation sequence is decided to determine reliability design activities. Thirdly, a closed control process of FMCS mitigation is provided integrated with logic decision method. By exposing the design of a helicopter fuel system, the present study demonstrates that all approaches are feasible, and the relationship between reliability parameters and qualitative design exists. Hence the failure modes mitigation could be controlled for the achievement of quantitative reliability requirements.
Podstawowym problemem w procesie projektowania niezawodności jest ograniczenie przyczyn uszkodzeń produktu. Jednakże, w przypadku sieci połączeń pomiędzy możliwymi przyczynami uszkodzeń złożonego produktu, trudno jest ustalić mapę zależności pomiędzy ograniczaniem przyczyn uszkodzeń i ilościowymi wartościami niezawodności, a decyzje względem ograniczania przyczyn uszkodzeń muszą bazować na własnym doświadczeniu, co znacznie wydłuża okres projektowania. W celu rozwiązania powyższych problemów, zaproponowano oryginalną, opartą na logice, metodę kontroli ograniczania przyczyn uszkodzeń i ilościowej analizy niezawodności systemu. Na wstępie, zaproponowano mieszany proces aktywnej i pasywnej kontroli niezawodności projektu. Następnie, zaprezentowano oryginalną koncepcję zbioru korelacji przyczyn uszkodzeń (FMCS) i metodę oznaczania opartą o teorię dedukcji. Na podstawie zmian dotyczących prawdopodobieństwa występowania przyczyn uszkodzeń, określono wzory niezawodności części i układów w celu pokazania wpływu ograniczania przyczyn uszkodzeń na niezawodność części i układów. Określono następnie ograniczającą sekwencję FMCS, ażeby ustalić założenia dla projektowania niezawodności. Na koniec zaprezentowano zamknięty proces kontroli ograniczania FMCS w powiązaniu z logiczną metodą podejmowania decyzji. Analizując pod tym kątem projekt systemu paliwowego helikoptera, wykazano w niniejszej pracy przydatność wszystkich powyższych metod, jak również związek pomiędzy parametrami niezawodności a projektowaniem jakościowym. Dlatego też ograniczanie przyczyn uszkodzeń powinno być kontrolowane w celu osiągnięcia wymaganej niezawodności ilościowej.
Źródło:
Eksploatacja i Niezawodność; 2015, 17, 1; 100-106
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Compact High Current Vacuum Diode Based on a Ceramic-Metal Welding Interface
Autorzy:
Xun, T.
Zhang, J.
Yang, H.
Wang, Y.
Liu, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1807886.pdf
Data publikacji:
2009-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
52.59.Mv
73.20.-r
84.70.+p
Opis:
For one kind of high current diodes composed of a ceramic-metal welding vacuum interface, the electrical design was presented. For compactness, a radial type insulator and a cone-column anode crust were adopted. The shielding methods around cathode and anode region were applied to mitigate the influence of welding solder to vacuum flashover. Finite Element Analysis (FEA) simulation results indicated that by adjusting the anode outline and shielding shape, the electric fields along the ceramic were well distributed. High voltage test was conducted on a long-pulse accelerator and experimental results confirm the theoretic design: the diode can stably hold on 400 kV and 200 ns voltage pulse.
Źródło:
Acta Physica Polonica A; 2009, 115, 6; 1013-1015
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reliability analysis of the products subject to competing failure processes with unbalanced data
Oparta na niezbilansowanych danych analiza niezawodności produktów podlegających procesom powstawania uszkodzeń konkurujących
Autorzy:
Li, J.
Zhang, Y.
Wang, Z.
Fu, H.
Xiao, L.
Powiązania:
https://bibliotekanauki.pl/articles/1365849.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
reliability evaluation
competing failure model
unbalanced data
interval statistics
ocena niezawodności
model uszkodzeń konkurujących
dane niezbilansowane
statystyki przedziałowe
Opis:
Considering the degradation and catastrophic failure modes simultaneously, a general reliability analysis model was presented for the competing failure processes with unbalanced data. For the degradation process with highly unbalanced data, we developed a linear random-effects degradation model. The model parameters can be estimated based on a simple least square method. Furthermore, to fully utilize the degradation information, we considered the last measured times of the degradation units that had only one or two measured time points as zero-failure data or right-censored data of the catastrophic failure mode. Then the incomplete data set was composed of zero-failure data and catastrophic failure data. To analyze the incomplete data, the definition of the interval statistics was firstly given. The best linear unbiased parameter estimators of catastrophic failure were obtained based on the Gauss-Markov theorem. Then, the reliability function of the competing failure processes was given. The corresponding two-sided confidence intervals of the reliability were obtained based on a bootstrap procedure. Finally, a practical application case was examined by applying the proposed method and the results demonstrated its validity and reasonability.
W pracy przedstawiono ogólny model analizy niezawodności procesów związanych z powstawaniem uszkodzeń konkurujących, który pozwala na wykorzystanie danych niezbilansowanych oraz umożliwia jednoczesne uwzględnienie uszkodzeń wynikających z obniżenia charakterystyk i uszkodzeń katastroficznych. Opracowano liniowy model efektów losowych dla procesu degradacji o wysoce niezbilansowanych danych. Parametry tego modelu można określić na podstawie prostej metody najmniejszych kwadratów. Ponadto, aby w pełni wykorzystać informacje dotyczące obniżenia charakterystyk, dane pochodzące z ostatniego pomiaru jednostek podlegających degradacji, dla których przeprowadzono tylko jeden lub dwa pomiary, rozpatrywano jako dane o zerowym uszkodzeniu lub jako ucięte prawostronnie dane dotyczące uszkodzenia katastroficznego. W ten sposób otrzymano zbiór niepełnych danych składający się z danych o uszkodzeniach zerowych oraz danych o uszkodzeniach katastroficznych. Aby móc przeanalizować uzyskane niepełne dane, podano definicję statystyki przedziałowej. Najefektywniejszy nieobciążony estymator liniowy (BLUE) parametrów uszkodzeń katastroficznych uzyskano na podstawie twierdzenia Gaussa-Markowa. Następnie, podano wzór funkcji niezawodności procesów związanych z powstawaniem uszkodzeń konkurujących. Odpowiednie dwustronne przedziały ufności dla oszacowanej niezawodności uzyskano metodą bootstrapową. Na koniec, przedstawiono przypadek praktycznego zastosowania proponowanej metody, którego wyniki wykazały jej trafność i zasadność.
Źródło:
Eksploatacja i Niezawodność; 2016, 18, 1; 98-109
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies