检索结果-南通市图书馆

A Hybrid Offline-Online Approach to Adaptive Downlink Resource Allocation Over LTE

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 766-777页

作者： Satish Kumar Rajesh Devaraj Arnab sarkar IEEE the Department of Computer Science and Engineering IIT Guwahati

Radio resource management mechanisms in current and future wireless networks is expected to face an enormous challenge due to the ever increasing demand for bandwidth and latency sensitive applications on mobile devices. This is because an optimal resource allocation scheme which attempts to multiplex the available bandwidth in order to maximize Quality of service(QoS), will pose an exponential computational burden at eNodeB. In order to minimize such computational overhead, this work proposes a hybrid offline-online resource allocation strategy which effectively allocates all the available resources among flows such that their QoS requirements are satisfied. The flows are firstly classified into priority buckets based on real-time criticality factors. During the offline phase, the scheduler attempts to maintain the system load within a pre-specified safe threshold value by selecting an appropriate number of buckets. This offline selection procedure makes use of supervisory control theory of discrete event systems to synthesize an offline scheduler. Next, we have devised an online resource allocation strategy which runs on top of the offline policy and attempts to minimize the impact of the inherent variability in wireless networks. Simulation results show that the proposed scheduling framework is able to provide satisfactory QoS to all end users in most practical scenarios.

关键词： Discrete event systems (DES) hybrid scheduling long term evolution (LTE) quality of service (QoS) radio resource management supervisory control

Low Temperature Reduction of Graphene Oxide Using Hot-plate for Nanocomposites Applications

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2016年第5期32卷 411-418页

作者： Abdelrahman Hussein Sourav sarkar Byungki Kim School of Mechatronics Engineering Korea University of Technology and Education

A green, easy to reproduce method to obtain thermally reduced graphene oxide （GO） is described, The only requirement is a heating source, like a hot plate, that can reach -225 ℃ without any special setup requirements. Upon addition of graphene oxide, effective reduction could be achieved within 10 s. Starting flake size affects the yield of graphene, final structure and composition. A detailed characterization of the produced graphene using thermal analysis, spectroscopic methods, electron microscopy, X-ray diffraction and atomic force microscopy is presented. Application of the produced graphene as a filler to epoxy resin for mechanical reinforcement is also reported. Smaller flakes （Ds0 = 5.7 μm） showed improved ultimate tensile strength, fracture strain and plane strain fracture toughness compared to larger flakes （Ds0 = 47.9 μm） that showed negative effect. Both flake sizes showed a negligible effect on Young＇s modulus.

关键词： Graphene Nanocomposite Mechanical properties Fracture toughness

Si nanomebranes: Material properties and applications

在线全文

学校读者我要写书评

暂无评论

Nano Research 2021年第9期14卷 3010-3032页

作者： Arijit sarkar Yongjun Lee Jong-Hyun Ahn School of Electrical and Electronic Engineering Yonsei University50 Yonsei-roSeoul 03722Republic of Korea

Silicon(Si)has widely been used as an essential material in the modern semiconductor ***,new attempts have been actively made to apply Si to a variety of fields such as flexible electronic devices and biosensors by manufacturing Si nanomembranes(NMs)having nanometer *** particular,as the thickness of Si is reduced to a nanometer scale,its mechanical,electrical,and optical properties differ from that of its bulk form,which provides opportunities for the development of new conceptual *** this review,we present recent advances in Si NM technology that exhibit functional features different from the bulk *** addition,we discuss the opportunities and current challenges related to this field.

关键词： Si nanomebranes flexible electronics bio-integrated electronics Si optoelectronics strain engineering

Bound for the Regularity of Binomial Edge Ideals of Cactus Graphs

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Algebra Colloquium 2022年第3期29卷 443-452页

作者： A.V.Jayanthan Rajib sarkar Department of Mathematics Indian Institute of Technology Madras Chennai 600036India

In this article,we obtain an upper bound for the regularity of the binomial edge ideal of a graph whose every block is either a cycle or a *** a consequence,we obtain an upper bound for the regularity of binomial edge... 详细信息

关键词： binomial edge ideal cactus graph Cohen-Macaulayness regularity

Bile salt induced solubilization of methylene blue: Study on methylene blue fluorescence properties and molecular mechanics calculation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2017年第1期7卷 71-75页

作者： Susithra Selvam Ivy sarkar Department of Chemistry Vel Tech University Avadi Chennai 600062 Tamilnadu India Department of Chemistry Indian Institute of Technology Madras Chennai 600036 Tamilnadu India

Methylene blue(MB) is a hydrophobic drug molecule, having importance both as a staining reagent and pharmaceutical agent. MB is strongly fluorescent, with an emission peak at 686 nm(λ_(ex)665 nm). In the study,the possibility of MB as an extrinsic fluorophore to study the micellization behavior of bile salts(BSs) was carried out. Since BSs are drug delivery systems, the solubilization of hydrophobic MB drug molecule by BSs was achieved and the nature of association of MB with BS media, namely sodium cholate(Na C) and sodium deoxycholate(Na DC) was evaluated. Change in the photophysical properties of MB is monitored through fluorescence intensity and fluorescence anisotropy at emission peak, 686 nm of MB. Molecular mechanics calculations were carried out to evaluate the MB–BS association. The estimated heat of formation, ΔH_f values are –625.19 kcal/mol for MB–Na C and –757.48 kcal/mol for MB–Na DC. The photophysical study also revealed that MB reports the step-wise aggregation pattern of BSs media, as an extrinsic fluorescence probe.

关键词： Methylene blue Sodium deoxycholate Sodium cholate Absorption Fluorescence spectroscopy Molecular mechanics

Galaxy Interactions in Filaments and Sheets:Effects of the Large-scale Structures Versus the Local Density

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2023年第2期23卷 197-204页

作者： Apashanka Das Biswajit Pandey Suman sarkar Department of Physics Visva-Bharati UniversitySantiniketanBirbhum731235India Department of Physics Indian Institute of Science Education and Research TirupatiTirupati-517507Andhra PradeshIndia

Major interactions are known to trigger star formation in galaxies and alter their *** study the major interactions in filaments and sheets using SDSS data to understand the influence of large-scale environments on galaxy *** identify the galaxies in filaments and sheets using the local dimension and also find the major pairs residing in these *** star formation rate(SFR) and color of the interacting galaxies as a function of pair separation are separately analyzed in filaments and *** analysis is repeated for three volume limited samples covering different magnitude *** major pairs residing in the filaments show a significantly higher SFR and bluer color than those residing in the sheets up to the projected pair separation of~50 *** observe a complete reversal of this behavior for both the SFR and color of the galaxy pairs having a projected separation larger than 50 *** earlier studies report that the galaxy pairs align with the filament *** alignment inside filaments indicates anisotropic accretion that may cause these *** do not observe these trends in the brighter galaxy *** pairs in filaments and sheets from the brighter galaxy samples trace relatively denser regions in these *** absence of these trends in the brighter samples may be explained by the dominant effect of the local density over the effects of the large-scale environment.

关键词： methods statistical-methods data analysis-galaxies evolution-galaxies interactions-(cosmology:)large-scale structure of universe

Galaxy Interactions in Filaments and Sheets:Insights from EAGLE Simulations

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2023年第11期23卷 161-168页

We study the color and star formation rates of paired galaxies in filaments and sheets using the EAGLE *** find that the major pairs with pair separation50 kpc)in filaments are on average redder and low-star-forming compared to those embedded in *** galaxies in filaments and sheets may have different stellar mass and cold gas mass *** a KS test,we find that for paired galaxies with pair separation<50 kpc,there are no significant differences in these properties in sheets and *** filaments transport gas toward the cluster of *** earlier studies find preferential alignment of galaxy pairs with the filament *** alignment of galaxy pairs may lead to different gas accretion efficiency in galaxies residing in filaments and *** propose that the enhancement of star formation rate at smaller pair separation in filaments is caused by the alignment of galaxy pairs.A recent study with SDSS data reports the same *** confirmation of these results by the EAGLE simulations suggests that the hydrodynamical simulations are powerful theoretical tools for studying galaxy formation and evolution in the cosmic web.

关键词： methods:data analysis methods:statistical galaxies:evolution galaxies:interactions (cosmology:)large-scale structure of universe

Do Minor Interactions Trigger Star Formation in Galaxy Pairs?

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2023年第9期23卷 322-340页

We analyze the galaxy pairs in a set of volume limited samples from the Sloan Digital Sky Survey to study the effects of minor interactions on the star formation rate(SFR)and color of *** carefully design control samples of isolated galaxies by matching the stellar mass and redshift of the minor *** SFR distributions and color distributions in the minor pairs differ from their controls at>99%significance *** also simultaneously match the control galaxies in stellar mass,redshift and local density to assess the role of the *** null hypothesis can be rejected at>99%confidence level even after matching the *** analysis shows a quenching in the minor pairs where the degree of quenching decreases with the increasing pair separation and plateaus beyond 50 *** also prepare a sample of minor pairs with Hαline *** calculate the SFR of these galaxies using the Hαline and repeat our *** observe a quenching in the Hαsample *** find that the majority of the minor pairs are quiescent systems that could be quenched due to minor *** data from the Galaxy Zoo and Galaxy Zoo 2,we find that only∼1%galaxies have a dominant bulge,4%–7%galaxies host a bar and 5%–10%of galaxies show active galactic nucleus(AGN)activity in minor *** indicates that the presence of bulge,bar or AGN activity plays an insignificant role in quenching the galaxies in minor *** more massive companion satisfies the criteria for mass quenching in most of the minor *** propose that the stripping and starvation likely caused the quenching in the less massive companion at a later stage of evolution.

关键词： methods statistical-galaxies formation-methods data analysis-galaxies interactions-galaxies star formation-(cosmology )large-scale structure of universe

A remote sensing based analysis of climate change in Sikkim supported by evidence from the field

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2021年第5期18卷 1256-1267页

作者： Rumia BASU Gourav MISRA Dipto sarkar Department of Earth and Ocean Sciences National University of IrelandH91TK33 GalwayIreland Department of Geography University College CorkT12K8AF CorkIreland Department of Geography and Environmental Studies Carleton UniversityK1S5B6 OttawaCanada

The Himalayas hailed as the‘water towers of the world’feed many perennial rivers which form the lifeline of the Indian *** change induced rising global temperatures and changing rainfall patterns are currently threatening the glaciers that feed the *** combination of these factors is causing water stresses to a part of the world which is usually considered water *** there are some large-scale studies done in the Himalayas,regional analysis of changing rainfall patterns and their impacts on vegetation and agriculture is *** we focus on the Indian state of Sikkim located in the Eastern Himalayas to evaluate these issues using mixed *** use satellite data from PERSIANN and MODIS to characterise the regional rainfall,vegetation,and surface temperature trends between 2001 and *** the analysis shows overall declining rainfall trends across most land cover classes,the trends in temperature are mostly positive for the period of study,with winter Land Surface Temperature(LST)values showing the largest area with marginally significant(p<0.1)positive *** contrast,such patterns are not observed for ***,the interviews corroborate that even agriculture is impacted,implying that the trends continue at finer spatial scales *** lack of government support for adaptation and mitigation is also lamented placing the communities at a precarious position to continuing climate change.

关键词： Climate change Rainfall Temperature Vegetation Mixed methods Sikkim