Informacja

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

Wyszukujesz frazę "Roy, S." wg kryterium: Autor


Tytuł:
Impact of roguing and insecticide spraying on mosaic disease in Jatropha curcas
Autorzy:
Al-Basir, F.
Roy, P. K.
Ray, S.
Powiązania:
https://bibliotekanauki.pl/articles/205846.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
Jatropha curcas
mosaic disease
roguing
spraying
Hopf bifurcation
optimal control problem (OCP)
Opis:
Jatropha curcas plant is greatly impaired by mosaic disease, caused by the viruses (Begomovirus), transmitted by whiteflies, which act as the vector. Roguing (i.e. removal of infected plant) and spraying of insecticides are common methods, employed in order to get rid of the disease. In this article, a mathematical model has been developed to study the mosaic disease dynamics while considering preventive measures of roguing and insecticide spraying. Sufficient conditions for the stability of equilibrium points of the system are among the results obtained through qualitative analysis. We obtain the basic reproduction number R0 and show that the disease free system is stable for R0 < 1 and unstable for R0 > 1. The region of stability of equilibrium points in different parameter spaces have also been analysed. Hopf bifurcation at the endemic steady state has been studied subsequently, as well. Finally, by formulating an optimal control problem, optimal application of roguing and spraying techniques has been determined, keeping in mind the cost effective control of the mosaic disease. Pontryagin minimum principle has been utilized to solve the optimal control problem. Numerical simulations illustrate the validity of the analytical outcomes.
Źródło:
Control and Cybernetics; 2017, 46, 4; 325-344
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of Cutting Forces and Chip Microstructure in High Speed Machining of Carbon Fiber - Epoxy Composite Tube
Autorzy:
Allwin Roy, Y.
Gobivel, K.
Vijay Sekar, K. S.
Suresh Kumar, S.
Powiązania:
https://bibliotekanauki.pl/articles/352953.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
composite materials
orthogonal machining
cutting forces
chip microstructure
Opis:
Carbon fiber reinforced polymeric (CFRP) composite materials are widely used in aerospace, automobile and biomedical industries due to their high strength to weight ratio, corrosion resistance and durability. High speed machining (HSM) of CFRP material is needed to study the impact of cutting parameters on cutting forces and chip microstructure which offer vital inputs to the machinability and deformation characteristics of the material. In this work, the orthogonal machining of CFRP was conducted by varying the cutting parameters such as cutting speed and feed rate at high cutting speed/feed rate ranges up to 346 m/min/ 0.446 mm/rev. The impact of the cutting parameters on cutting forces (principal cutting, feed and thrust forces) and chip microstructure were analyzed. A significant impact on thrust forces and chip segmentation pattern was seen at higher feed rates and low cutting speeds.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 3; 1771-1777
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Studies on Isotope Shift Exponent and Pressure Coefficient for Extended Superconductors within BCS Formalism
Autorzy:
Banerjee, B.
Roy, S.
Powiązania:
https://bibliotekanauki.pl/articles/1808029.pdf
Data publikacji:
2009-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.20.+f
74.25.Bt
74.25.Ha
Opis:
A tight-binding model comprising a hopping and an attractive interaction term was considered for high temperature superconductors. Explicit calculations on the effects of isotopic substitution of atoms and application of pressure on the transition temperatures were made in this work. Exact analytical expressions for the isotope-shift exponent (α) and pressure coefficient $(γ_P)$ of transition temperature $(T_C)$ considering the isotopic mass and pressure dependence of the hopping and attractive interaction strengths from a minimal model describing superconductivity were obtained. Theoretical predictions for α and $γ_P$ with proper choice of parameters are found to be qualitatively consistent with the results of the experiments of high $T_C$ oxides. The results depend on the band dispersion chosen.
Źródło:
Acta Physica Polonica A; 2009, 115, 5; 914-919
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zrozumieć zagładę : społeczna psychologia Holokaustu
Understanding genocide : the social psychology of the Holocaust
Autorzy:
Baumeister, Roy F. (1953- ).
Współwytwórcy:
Newman, Leonard S. (1961- ). Redakcja
Erber, Ralph (1954- ). Redakcja
Bilewicz, Michał (1980- ). Redakcja
Budziszewska, Magdalena. Tłumaczenie
Data publikacji:
2009
Wydawca:
Warszawa : Wydawnictwo Naukowe PWN
Tematy:
Holocaust socjologia
Psychologia społeczna
Opis:
Nazwy aut. na skrzydełku okł.
Bibliogr. s. 307-335. Indeksy.
Dostawca treści:
Bibliografia CBW
Książka
Tytuł:
Electron-ion Recombination at Sub-zero Temperature
Autorzy:
Bhattacharyya, S.
Roy, A.
Powiązania:
https://bibliotekanauki.pl/articles/2008325.pdf
Data publikacji:
1999-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
32.70.Fw
34.80.Kw
Opis:
In this paper we have considered two-step radiative recombination channel over the existing spontaneous radiative recombination channel to explain the causes of experimentally obtained enhanced recombination rate at sub-zero temperature. The existing recombination rate due to spontaneous radiative recombination is 4 times smaller than the recent experimental data. In the case of Ne$\text{}^{10+}$ we obtain good agreement between theory and experiment when contribution from two-step radiative recombination channel is added to the spontaneous radiative recombination channel. Recombination rate for Ar$\text{}^{18+}$ is calculated. The radiation spectrum given out by two-step radiative recombination and spontaneous radiative recombination in the recombination rate processes are discrete spectrum and continuous spectrum, respectively. Experimental identification of these two channels through the spectral signatures is suggested.
Źródło:
Acta Physica Polonica A; 1999, 95, 6; 911-920
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Three-Particle Recombination at Low Temperature: a QED Approach
Autorzy:
Bhattacharyya, S.
Roy, A.
Powiązania:
https://bibliotekanauki.pl/articles/2027431.pdf
Data publikacji:
2001-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
32.80.Fb
33.55.Ad
Opis:
A theoretical study of the three-body recombination of proton and electron in presence of a spectator electron with electronic beam at near-zero temperature is presented using field theory and invariant Lorentz gauge. Contributions from the Feynman diagrams of different orders give an insight into the physics of the phenomena. Recombination rate coefficient is obtained for low lying principal quantum number n=1 to 10. At a fixed ion beam temperature (300 K) recombination rate coefficient is found to increase in general with n, having a flat and a sharp peak at quantum states 3 and 5, respectively. In absence of any other theoretical and experimental results for low temperature formation of H-atom by three-body recombination at low lying quantum states, we have presented the theoretical results of Stevefelt and group for three-body recombination of deuteron with electron along with the present results. Three-body recombination of antihydrogen in antiproton-positron plasma is expected to yield similar result as that for three-body recombination of hydrogen formation in proton-electron plasma. The necessity for experimental investigation of low temperature three-body recombination at low quantum states is stressed.
Źródło:
Acta Physica Polonica A; 2001, 100, 1; 23-40
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemical-induced seed germination and enhancement of seed potential of seven wild plant taxa of Ericaceae in India
Autorzy:
Chandan Kumar, Pati
Bhattacharjee, Aloke
Roy, Priyankar
Mahanty, Dibyendu S.
Panda, Subhasis
Powiązania:
https://bibliotekanauki.pl/articles/1158777.pdf
Data publikacji:
2018
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Ericaceae
Seed germination
T50 of germination
catalase
protein
seed metabolism
Opis:
Pretreatment of seeds of seven wild plant taxa (viz., Gaultheria hookeri C. B. Clarke, G. stapfiana Airy Shaw, G. semi-infera (C. B. Clarke) Airy Shaw, G. trichophylla Royle var. ovata Panda & Sanjappa, Lyonia ovalifolia (Wall.) Drude var. ovalifolia, Pieris formosa (Wall.) D. Don and Vaccinium glauco-album C. B. Clarke) in the family Ericaceae using Na-dikegulac (Na-DK) for 8 hours (4 + 4 h in two installments) before keeping in ambient storage condition (32±2 ºC) for different durations (0 and 20 days) slowed down the rapid loss of germination and reduced the time (h) required for 50% seed germination (T50). Concomitantly, the reduction of protein level as well as the activity of catalase of seed kernels during storage period was ameliorated to a significant extent in the chemical pretreated seed lots.
Źródło:
World Scientific News; 2018, 114; 249-255
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Spectrum Sensing Parameters in Cognitive Radio Using Adaptive Genetic Algorithm
Autorzy:
Chatterjee, S.
Dutta, S.
Bhattacharya, P. P.
Roy, J. S.
Powiązania:
https://bibliotekanauki.pl/articles/308511.pdf
Data publikacji:
2017
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
adaptive genetic algorithm
bandwidth
cognitive radio
spectrum sensing
throughput
Opis:
Quality of service parameters of cognitive radio, like, bandwidth, throughput and spectral efficiency are optimized using adaptive and demand based genetic algorithm. Simulation results show that the proposed method gives better real life solution to the cognitive radio network than other known approach.
Źródło:
Journal of Telecommunications and Information Technology; 2017, 1; 21-27
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculation of Lattice Relaxation in Some Substitutional Alloys Using a Green Function
Autorzy:
Das, S. K.
Datta Roy (Paul), S.
Powiązania:
https://bibliotekanauki.pl/articles/1995663.pdf
Data publikacji:
1999-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.Bb
61.82.Bg
Opis:
In this paper we calculate nearest neighbour relaxation in some dilute substitutional alloys using a lattice static Green function and the Morse potential function. Distant neighbour relaxation is calculated by invoking a continuum approximation. The potential parameters for the unlike interactions are calculated using simple interpolation formulae. Using the above relaxation, we calculate volume changes in the above alloys. It is observed that the simple model predicts values which are in reasonably good agreement with the experimental values in all cases. The calculated values are also compared with those obtained from the Vegard law. For Au-Ag alloy, our model reproduces both the correct sign and the magnitude of the volume change, whereas the Vegard law cannot even give the sign of the volume change. This shows the inherent strength of the present model.
Źródło:
Acta Physica Polonica A; 1999, 95, 3; 359-366
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Green Function Estimation of Correction to Vegards Law for isovalent Substitutional Defects in Alkali Halide Crystals
Autorzy:
Datta Roy (Paul), S.
Das, S. K.
Powiązania:
https://bibliotekanauki.pl/articles/2013286.pdf
Data publikacji:
2000-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.72.Bb
61.82.Bg
Opis:
A Green function method is developed for estimation of lattice parameter r(χ) of an AX-BX solid solution over entire composition range (χ=0 to 1). The r(χ) obtained in the present method is different from the value r$\text{}_{V}$(χ) suggested by Vegard's law. We estimated the deviation from Vegard's law, r(χ)-r$\text{}_{V}$(χ), over entire composition range for isovalent substitutional defect in alkali halide crystals. When compared to X-ray diffraction measurements, we find that the deviation is in correct direction, variation of r(χ) with χ is consistent with experiment and the overall agreement is fairly good considering the accuracy of the experiment.
Źródło:
Acta Physica Polonica A; 2000, 97, 4; 671-679
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reactive solute transport in blood flow through a permeable capillary
Autorzy:
Debnath, S.
Roy, A. K.
Bég, O. A.
Powiązania:
https://bibliotekanauki.pl/articles/38695392.pdf
Data publikacji:
2022
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
capillary
axial flow
radial flow
solute dispersion
Gill decomposition
filtration coefficient
exchange coefficient
advection coefficient
Opis:
The present analysis discusses the solute transport process in a steady 2D (axial and radial) laminar flow of blood through a permeable, finite length capillary. Blood is treated as a homogeneous Newtonian fluid and the solute is absorbed at the capillary wall with a linear irreversible reaction rate. The velocity profile is obtained by a regular perturbation technique, whereas the transport coefficients depicted by the Gill generalized dispersion model are solved numerically. A number of different scenarios are considered, namely transport with no-reaction, weak absorption, strong absorption, low filtration or high filtration, etc. In the initial stages, the temporal behaviour of the dispersion coefficient is identical to those cases when there is no radial velocity. For the combined effect of radial and axial velocities, however, the dispersion coefficient is lower for a high absorption rate than for a weak absorption rate. Diffusion is accelerated with higher values of filtration coefficient. Owing to the opposite effects of radial diffusion and radial velocity, the solute particles require more time to reach the steady state. The analysis finds applications in, for example, reactive nutrient and pharmacological transport in capillary hemodynamics.
Źródło:
Archives of Mechanics; 2022, 74, 2-3; 173-200
0373-2029
Pojawia się w:
Archives of Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Allergy to periwinkle pollen [Catharanthus roseus G.Don.]
Autorzy:
Ghosh, D
Roy, I.
Chanda, S.
Gupta-Bhattacharya, S.
Powiązania:
https://bibliotekanauki.pl/articles/51461.pdf
Data publikacji:
2007
Wydawca:
Instytut Medycyny Wsi
Tematy:
garden plant
human disease
pollen
Apocynaceae
aeroallergen
respiratory allergy
allergy
Catharanthus roseus
Madagascar periwinkle plant
allergen
Opis:
Catharanthus roseus G. Don. (CR) or periwinkle plants are widely grown/cultivated as garden plants in the tropics and subtropics. In spite of its predominantly entomophilous nature, CR pollen had been reported to be airborne and allergenic. The objective of this study was to discover the seasonal changes of CR pollen concentration in air, to determine its potential to cause respiratory allergy and to analyze its allergenic components. A 2-year aerobiological survey was conducted with a Burkard 7-day sampler in an agricultural farm in the suburban zone of Calcutta city where CR pollen was found to be almost perennial with 3.6-5.4% contribution to the aeropollen load. Skin prick test was conducted on 282 respiratory allergic individuals living within a 15 km radius of the study area. 29.8% of them were positive to CR pollen. Among them, 80.9% were directly involved in gardening. The whole pollen extract was subjected to gel fi ltration in a Sephacryl S-200 column. Among 5 eluted fractions, fraction I showed optimum IgE-reactivity in ELISA-inhibition. The fraction I shows 4 protein components in SDS-PAGE, within which 3 (40-66 kD molecular mass) were found to be IgE-reactive in immunoblotting using patient sera. It can be concluded that CR pollen can trigger IgEmediated respiratory allergy in the people living in close proximity.
Źródło:
Annals of Agricultural and Environmental Medicine; 2007, 14, 1
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bright Solitons in Asymmetrically Trapped Bose-Einstein Condensates
Autorzy:
Golam Ali, Sk.
Talukdar, B.
Roy, S. K.
Powiązania:
https://bibliotekanauki.pl/articles/2047288.pdf
Data publikacji:
2007-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.75.-b
03.75.Kk
05.30.Jp
Opis:
We study the dynamics of bright solitons in a Bose-Einstein condensate confined in a highly asymmetric trap. While working within the framework of a variational approach we carry out the stability analysis of the Bose-Einstein condensate solitons against collapse. When the number of atoms in the soliton exceeds a critical number N$\text{}_{c}$, it undergoes the so-called primary collapse. We find an analytical expression for N$\text{}_{c}$ in terms of appropriate experimental quantities that are used to produce and confine the condensate. We further demonstrate that, in the geometry of the problem considered, the width of the soliton varies inversely as the number of constituent atoms.
Źródło:
Acta Physica Polonica A; 2007, 111, 3; 289-297
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Matter-Wave Bright Solitons of $\text{}^7Li$ Gas in an Expulsive Potential
Autorzy:
Golam Ali, Sk.
Talukdar, B.
Roy, S.
Powiązania:
https://bibliotekanauki.pl/articles/1814020.pdf
Data publikacji:
2007-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.75.Fi
05.45.Yv
Opis:
A Lagrangian based method is used to derive an analytical model for studying the dynamics of matter-wave bright soliton created in a harmonic potential which is attractive in the transverse direction and expulsive in the longitudinal direction. By means of sech trial functions and a Ritz optimization procedure, evolution equations are constructed for width, amplitude and nonlinear frequency chirp of the propagating soliton of the atomic condensate. Our equation for the width is an exact agreement with that of Carr and Castin, obtained by more detailed analysis. In agreement with the experiment of Paris group, the expulsive potential is found to cause the soliton to explode for N|$a_s$|=0.98, N being the number of atoms in the condensate and $a_s$ -- the scattering length of the atom-atom interaction.
Źródło:
Acta Physica Polonica A; 2007, 112, 6; 1165-1170
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
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