Informacja

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

Wyszukujesz frazę "Pathak, K." wg kryterium: Autor


Wyświetlanie 1-8 z 8
Tytuł:
Single Ionization of He by High-Energy Proton and Antiproton. A QED Approach
Autorzy:
Bhattacharyya, S.
Pathak, K.
Powiązania:
https://bibliotekanauki.pl/articles/2014235.pdf
Data publikacji:
2000-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
34.80.Dp
82.30.Fi
Opis:
We have investigated single ionization of He by fast proton and antiproton using a QED approach. A field theoretical calculation gives the total cross-section of He in single ionization, from which it is seen that the projectile p$\text{}^{+}$ or p$\text{}^{-}$ gives almost the same values of cross-section. We have also compared our results with other theoretical and experimental results available in this context yet. Behaviour of the cross-section at a lower spectrum of projectile energy is discussed.
Źródło:
Acta Physica Polonica A; 2000, 98, 4; 335-344
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Angular Differential Cross-Sections for Electron Transfer in Collisions between Proton and He$\text{}^{+}$(1s) Ions
Autorzy:
Bhattacharyya, S.
Pathak, K.
Becker, A.
Faisal, F. H. M.
Powiązania:
https://bibliotekanauki.pl/articles/1952747.pdf
Data publikacji:
1996-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
34.70.+e
34.40.+n
Opis:
Angular differential cross-sections for the formation of H, as a result of electron capture by proton from He$\text{}^{+}$(1s) at the centre-of-mass energies from 4 to 24 keV, are calculated using distorted wave Coulomb-Born approximation. The total interaction potentials in the prior-interaction channel and in the post-interaction channel are considered. Coulomb boundary conditions are taken care of with the proper choice of the perturbation potentials in both the prior and the post channels. A prior-post discrepancy is noted. Existing theoretical results are presented along with the present results.
Źródło:
Acta Physica Polonica A; 1996, 90, 6; 1143-1153
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Integrated Reverse Engineering Approach for Accuracy Control of Free-Form Objects
Zastosowanie zintegrowanych metod inżynierii odwrotnej do kontroli dokładności wykonania obiektów o dowolnych kształtach
Autorzy:
Pathak, V. K.
Nayak, C.
Singh, A. K.
Chaudhary, H.
Powiązania:
https://bibliotekanauki.pl/articles/139656.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
surface accuracy
computer-aided tools
free form shapes
reverse engineering
dokładność powierzchni
narzędzia wspomagania komputerowego
dowolne kształty
inżynieria odwrotna
Opis:
Computer-aided tools help in shortening and eradicating numerous repetitive tasks that reduces the gap between digital model and actual product. Use of these tools assists in realizing free-form objects such as custom fit products as described by a stringent interaction with the human body. Development of such a model presents a challenging situation for reverse engineering (RE) which is not analogous with the requirement for generating simple geometric models. Hence, an alternating way of producing more accurate three-dimensional models is proposed. For creating accurate 3D models, point clouds are processed through filtering, segmentation, mesh smoothing and surface generation. These processes help in converting the initial unorganized point data into a 3D digital model and simultaneously influence the quality of model. This study provides an optimum balance for the best accuracy obtainable with maximum allowable deviation to lessen computer handling and processing time. A realistic non trivial case study of free-form prosthetic socket is considered. The accuracy obtained for the developed model is acceptable for the use in medical applications and FEM analysis.
Narzędzia wspomagania komputerowego pomagają skrócić lub wyeliminować powtarzające się wielokrotnie zadania w procesie redukowania różnic pomiędzy rzeczywistym produktem a jego modelem cyfrowym. Ich zastosowanie pomaga realizować obiekty o dowolnych kształtach, takie jak produkty dopasowane indywidualnie, przeznaczone do ścisłego współdziałania z ciałem człowieka. Opracowanie modeli podobnego rodzaju stanowi dla inżynierii odwrotnej wyzwanie nieporównywalnie trudniejsze od tego, jakim jest tworzenie modeli o prostych formach geometrycznych. Biorąc powyższe pod uwagę, autorzy zaproponowali alternatywną drogę tworzenia dokładniejszych modeli trójwymiarowych. W celu realizacji tego zadania trójwymiarowe chmury punktów są przetwarzane drogą filtracji, segmentacji, wygładzania siatki i generacji powierzchni. Zastosowane procesy przetwarzania pomagają przekształcić początkowy nieuporządkowany zbiór danych w model trójwymiarowy, wpływając jednocześnie na jakość tego modelu. W pracy zaproponowano kompromis pomiędzy osiąganiem najlepszej dokładności przy dopuszczalnych odchyłkach a zmniejszeniem obciążenia komputera i czasu przetwarzania danych. Rozważono realistyczny, nietrywialny przypadek modelu o złożonym kształcie – trzonu protezy kończyny. Dokładność uzyskanego modelu okazała się wystarczająca do zastosowań medycznych oraz do celów analizy MES.
Źródło:
Archive of Mechanical Engineering; 2016, LXIII, 4; 647-663
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flow dynamics study of catalyst powder in catalytic cracking unit for troubleshooting
Autorzy:
Yelgaonkar, V.
Agrahari, G.
Vikrant, D.
Prasanna, R.
Pathak, B. K.
Powiązania:
https://bibliotekanauki.pl/articles/147563.pdf
Data publikacji:
2017
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
catalytic cracking unit
cyclones
fractionator
radiotracer
plug flow
Opis:
Gamma scanning and radiotracer applications are very effective and inexpensive tools to understand and optimize the process as well as troubleshoot the various types of problems in many chemical, petrochemical industries and refineries. These techniques are non-invasive; hence, the problems can be pinpointed online, which leads to reduce the downtime, schedule the shutdown and maintenance of the plant equipment, rendering huge economic benefits. In a leading refinery of India, the catalytic cracking unit (CCU) was malfunctioning. It was suspected by the refinery engineers that the catalyst powder was being carried over to the fractionator, which could have led to erosion of the fractionator column internals resulting in their rupture, and consequentially, to the fire hazard. To understand the flow behaviour of the catalyst powder and to ensure the mechanical integrity, catalyst accumulation and choking, both radiotracer study and gamma scanning of the CCU reactor was carried out. The reactor consists of a riser, three primary cyclones and three secondary cyclones. Gamma scanning of the reactor was carried out with the help of an automatic gamma scanner using 1.8 GBq of Co-60 sealed source. Results showed that the catalyst powder was accumulated in one of the secondary cyclones and uneven density distribution was observed in another secondary cyclone. The radiotracer study was carried out using the irradiated catalyst powder as a radiotracer, which contains 0.9 GBq of Na-24. The radiotracer was injected in the reactor through the specially fabricated injection system. Radiation measurement was done using the thermally insulated and collimated NaI(Tl) scintillation detectors located at various strategic locations coupled to a multi-detector data acquisition system. The data were mathematically analysed. It was confirmed that the catalyst powder was accumulated in one of the secondary cyclones with no flow downwards. This resulted in excess powder available to travel along with hydrocarbon towards fractionator. Since the quantity of powder released through the hydrocarbon outlet of CCU was higher than the designed value, the catalyst powder was observed in various zones of the fractionator. Mathematical modelling of the radiotracer data obtained at various locations corroborated the scanning results; also, the flow pattern was obtained. Partially blocked secondary cyclone showed plug flow with recirculation; normal working cyclone had plug flow behaviour and the vortex breaker showed parallel flow.
Źródło:
Nukleonika; 2017, 62, 4; 277-283
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of Heterogeneous Road Traffic Noise in Nagpur
Autorzy:
Lokhande, S. K.
Pathak, S. S.
Kokate, P. A.
Dhawale, S. A.
Bodhe, G. L.
Powiązania:
https://bibliotekanauki.pl/articles/176717.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
traffic noise
FHWA
Federal Highway Administration
TNM
Traffic Noise Model
Prediction Model
LAeq,T
a-weighted time-average sound level
noise pollution
Opis:
The objective of the study is to assess the noise scenario and evaluate prediction model for heterogeneous traffic conditions. In the past few years, road traffic of Nagpur has increased significantly due to the rapid increase in the number of vehicles. Noise levels are monitored at six different squares, characterized as interrupted traffic flow due to traffic signals, high population density and heavy traffic where the major sources of noise are engines, exhausts, tires interacting with the road, horns, sound of gear boxes, breaks, etc. The A-weighted time-average sound levels (LAeq, T) are measured at the different time of day during peak and off-peak traffic hours. To assess the traffic noise more precisely, the noise descriptors such as L10, L50, L90, LAeq, T, TNI (Traffic Noise Index), NPL (Noise Pollution Level) and NC (Noise Climate) are used. In the present study, the Federal Highway Administration (FHWA) noise prediction model is used for prediction of noise levels and it is observed that one-hour duration measured LAeq, T ranged from 71 to 76 dB(A) and 71.6 to 76.3 dB(A) during peak and off peak hours respectively. Due to the heavy traffic the peak hour Sound Exposure Levels (LAE) at all locations are exceeding permissible limit of 70 dB(A) prescribed by the World Health Organization (W.H.O). Off-peak traffic hour noise levels are within permissible limit except at two locations, Jagnade and HB town square. Significant correlation was obtained when best fit lines generated between measured and predicted values gives R2 of 0.455 for all time intervals. Chi-Square test (X2) was also computed to investigate the noise levels at different squares. The results show that the inhabitants of Nagpur city are exposed to high transportation noise during daytime.
Źródło:
Archives of Acoustics; 2018, 43, 1; 113-121
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular surveillance of hepatitis and tuberculosis infections in a cohort exposed to methyl isocyanate
Autorzy:
Mishra, Pradyumna K.
Bhargava, Arpit
Pathak, Neelam
Desikan, Prabha
Maudar, Kewal K.
Varshney, Subodh
Shrivastava, Rahul
Jain, Aruna
Powiązania:
https://bibliotekanauki.pl/articles/2185470.pdf
Data publikacji:
2011-03-01
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
bhopal gas tragedy
molecular epidemiology
occult hepatitis
latent tuberculosis
translational research
Opis:
Objective: The potential toxic effects on the immune system exerted by occupational and accidental environmental exposures and underlying molecular regulatory mechanisms involved in the etiology and progression of infectious diseases are now being characterized. The Bhopal gas tragedy is undoubtedly one of the worst industrial disasters in the history of mankind. After 25 years of accidental exposure to methyl isocyanate (MIC), severe systemic ailments still continue to preoccupy the lives of the affected population that survived this tragedy. We have performed a molecular surveillance study to characterize hepatitis and tuberculosis infections amongst the first and the second generation of survivors exposed to MIC. Materials and Methods: Both outdoor and indoor patients referred for molecular diagnosis of hepatitis B virus (HBV), hepatitis C virus (HCV) and Mycobacterium tuberculosis (MTB) were examined. Qualitative analysis for HBsAg, anti-HBc, anti-HCV through ELISA was performed, while BacT/ALERT and Ziehl-Neelson technique were utilized for the assessment of tuberculosis. Detection and quantification of viral and bacterial nucleic acid and characterization of hepatitis genotypes were analyzed using real-time and end-point PCR techniques. Results: The results suggest that HBV infections are most common among the MIC-exposed cohort, followed by extra-pulmonary and pulmonary MTB and HCV infections. Genotype 3 is the most prevalent HCV genotype among the survivors. Failure to detect HBsAg, anti-HBc and anti-HCV through ELISA, and tuberculosis by culture and Ziehl-Neelson stain, indicates higher prevalence of occult hepatitis and latent tuberculosis in the affected population. Conclusions: Our study underscores the importance of hospital-based records used as a data source for monitoring possible environmental health hazards. As the risk of progress of infection is often influenced by conditions and periods of environmental chemical exposure, therefore, insights of interconnected molecular pathways will further illuminate the gene-environment association and might offer valuable information for rational drug design.
Źródło:
International Journal of Occupational Medicine and Environmental Health; 2011, 24, 1; 94-101
1232-1087
1896-494X
Pojawia się w:
International Journal of Occupational Medicine and Environmental Health
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Appraisal of Noise Level Dissemination Surrounding Mining and Industrial Areas of Keonjhar, Odisha: a Comprehensive Approach Using Noise Mapping
Autorzy:
Lokhande, S. K.
Dhawale, S. A.
Pathak, S. S.
Gautam, R.
Jain, M. C.
Bodhe, G. L.
Powiązania:
https://bibliotekanauki.pl/articles/176752.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise mapping
noise prediction
predictor LimA
mining
GIS
Opis:
Noise mapping is a well-established practice among the European nations, and it has been follow for almost two decades. Recently, as per guidelines of the Directorate General of Mines Safety (DGMS), India, noise mapping has been made mandatory in the mining expanses. This study is an effort to map the noise levels in nearby areas of mines in the northern Keonjhar district. The motive of this study is to quantify the existing A-weighted time-average sound level (LAeq, T) in the study area to probe its effects on the human dwellings and noise sensitive areas with the probability of future development of the mines, roads, and industrial and commercial zone. The LAeq, T was measured at 39 identified locations, including industrial, commercial, residential, and sensitive zones, 15 open cast mines, 3 major highways, and 3 haulage roads. With the utilisation of Predictor LimA Software and other GIS tools, the worked out data is mapped and noise contours are developed for the visualisation and identification of the extent and distribution of sound levels across the study area. This investigation discloses that the present noise level at 60% of the locations in silence and residential zone exposed to significantly high noise levels surpasses the prescribed limit of Central Pollution Control Board (CPCB), India. The observed day and night time LAeq, T level of both zones ranged between 43.2–62.2 dB(A) and 30.5–53.4 dB(A), respectively, whereas, the average Ldn values vary between 32.7 and 51.2 dB(A). The extensive mobility of heavy vehicles adjoining the sensitive areas and a nearby plethora of open cast mines is the leading cause of exceeded noise levels. The study divulges that the delicate establishments like schools and hospitals are susceptible to high noise levels throughout the day and night. A correlation between observed and software predicted values gives R2 of 0.605 for Ld, 0.217 for Ln, and 0.524 for Ldn. Finally, the mitigation measure is proposed and demonstrated using a contour map showing a significant reduction in the noise levels by 0–5.3 dB(A).
Źródło:
Archives of Acoustics; 2017, 42, 3; 423-432
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-8 z 8

    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