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排序方式: 共有5233条查询结果,搜索用时 15 毫秒
21.
Yonghe Liu Sajal K. Das 《Communications Magazine, IEEE》2006,44(11):142-147
Conventional wireless sensor networks rely mostly on simple scalar data (such as temperature or humidity) and specialize in single-purpose applications. Taking a fundamental departure, in this article we motivate information-rich wireless video sensor networks that emulate the compound eyes found in certain arthropods. Although constrained by scarce resources, sensor nodes can only serve extremely low-resolution video streams; the availability of vast amount of such streams due to deployment redundance can suffice for the need of information hungry applications. Unfortunately, the unique characteristics of wireless video sensor networks will introduce novel uncertainty-driven challenges in the information-intensive and yet resource-constrained environment. Correspondingly, we describe key research problems in the areas of networking, security, sensor design, and video-data analysis 相似文献
22.
Y. L. Saraswathi S. Das D. P. Mondal 《Metallurgical and Materials Transactions A》2005,36(8):2259-2262
The erosion-corrsosion behavior of SiC particle-reinforced Al-Si alloy has been studied in NaOH slurry simulating the mining
atmosphere. The study was performed at two different sand concentrations, namely, 20 and 30 wt pct, and at a speed of 900
rpm. It is depicted that the wear rates decreased with increasing sand content, indicating that corrosion is the dominating
mode of material removal. Further composite exhibited lower wear resistance than the laloys irrespective of the sand concentration.
Scanning electron microscope (SEM) observations indicated the dissolution of dendrites of Al due to severe corrosion, leaving
behind the network of Si. This ultimately results in the falling of Si particles from the matrix, leaving behind voids. This
also results in the formation of voids around the SiC particles and leads to pullout of SiC particles from the matrix during
the wear process. 相似文献
23.
The plane strain problem of determining Stress Intensity Factors (SIF) for a moving interfacial Griffith crack between an elastic orthotropic half-plane and a dissimilar orthotropic layer with a moving punch situated along the boundary of the layer have been considered. The problem is reduced to the solution of three simultaneous singular integral equations with Cauchy-type singularities. Expressions for SIF for the case of a general loading are obtained. Numerical results for some particular cases are also presented graphically. 相似文献
24.
Shreyasee Das Nele Dewit Dirk Jacobs Yolande A. L. Pijnenburg Sjors G. J. G. In t Veld Salom Coppens Milena Quaglia Christophe Hirtz Charlotte E. Teunissen Eugeen Vanmechelen 《International journal of molecular sciences》2022,23(13)
Neurofilament light chain (Nf-L) is a well-known biomarker for axonal damage; however, the corresponding circulating Nf-L analyte in cerebrospinal fluid (CSF) is poorly characterized. We therefore isolated new monoclonal antibodies against synthetic peptides, and these monoclonals were characterized for their specificity on brain-specific intermediate filament proteins. Two highly specific antibodies, ADx206 and ADx209, were analytically validated for CSF applications according to well-established criteria. Interestingly, using three different sources of purified Nf-L proteins, a significant impact on interpolated concentrations was observed. With a lower limit of analytical sensitivity of 100 pg/mL using bovine Nf-L as the calibrator, we were able to quantify the Nf-L analyte in each sample, and these Nf-L concentrations were highly correlated to the Uman diagnostics assay (Spearman rho = 0.97, p < 0.001). In the clinical diagnostic groups, the new Nf-L ELISA could discriminate patients with Alzheimer’s disease (AD, n = 20) from those with frontotemporal lobe dementia (FTD, n = 20) and control samples with subjective cognitive decline (SCD, n = 20). Henceforth, this novel Nf-L ELISA with well-defined specificity and epitopes can be used to enhance our understanding of harmonizing the use of Nf-L as a clinically relevant marker for neurodegeneration in CSF. 相似文献
25.
Subodh K. Das John A. S. Green 《JOM Journal of the Minerals, Metals and Materials Society》2010,62(2):27-31
It is now possible to assess the impact of the production processes of aluminum on the environment and to describe some of the ongoing responses and opportunities for improvement. This is compared with the benefits of aluminum in transportation, where the growing usage in various forms of transport due to its low density, high strength, and ability to be recycled enables reduced mass, increased fuel efficiency, reduced emissions and increased safety. It is the purpose of this paper to compare and contrast the emissions generated in the production of aluminum with the benefits accruing from its increased use in transportation. 相似文献
26.
27.
Das B. Abdullah M. F. L. Pandey B. Hussain D. M. A. 《Wireless Personal Communications》2019,106(4):1767-1786
Wireless Personal Communications - Optical signal reinstatement (OSR) is a common technique used in high-speed communication systems. OSR can be achieved using various techniques such as;... 相似文献
28.
Das Madhu Sudan Samanta Anu Sanyal Sourish Mandal Sanjoy 《Wireless Personal Communications》2021,120(4):3389-3413
Wireless Personal Communications - Mobile robot navigation has been a current issue in the most recent two decades. Mobile robots are necessary to explore in obscure and dynamic situations. To... 相似文献
29.
Mainak?ChatterjeeEmail author Haitao?Lin Sajal?K.?Das 《Mobile Networks and Applications》2005,10(6):939-946
In this paper, we address the problem of user-class based service differentiation in CDMA networks. Users are categorized
into three classes who get differentiated services based on their expected quality of service (QoS) from the service provider
and the price they are willing to pay. We adopt a game theoretic approach for allocating resources through a two-step process.
During a service admission, resource distribution is determined for each class. Then, the resource allocated to each class
is distributed among the active users in that class. We devise a utility function for the providers which considers the expected
revenue and the probability of users leaving their service provider if they are not satisfied with the service. Our model
demonstrates how power can be controlled in a CDMA network to differentiate the service quality. Also, we show the impact
of admitting high paying users on other users.
Mainak Chatterjee received his Ph.D. from the department of Computer Science and Engineering at The University of Texas at Arlington in 2002.
Prior to that, he completed his B.Sc. with Physics (Hons) from the University of Calcutta in 1994 and M.E. in Electrical Communication
Engineering from the Indian Institute of Science, Bangalore, in 1998. He is currently an Assistant Professor in the department
of Electrical and Computer Engineering at the University of Central Florida. His research interests include economic issues
in wireless networks, applied game theory, resource management and quality-of-service provisioning, ad hoc and sensor networks,
CDMA data networking, and link layer protocols. He serves on the executive and technical program committee of several international
conferences.
Haitao Lin received the BE degree in radio engineering from Southeast University, Nanjing, China, in 1996, the MS degree in computer
applications from the Beijing University of Posts and Telecommunications, Beijing, China, in 2000, and Ph.D. in Computer Science
and Engineering from The University of Texas at Arlington in 2004. He is currently with Converged Multimedia Services System
Engineering at Nortel, Richardson, Texas. His research interests include wireless network performance evaluation and enhancement,
wireless link adaptation, wireless network resource management, and applied game theory.
Sajal K. Das received B.S. degree in 1983 from Calcutta University, M.S. degree in 1984 from Indian Institute of Science, Bangalore,
and Ph.D. degree in 1988 from University of Central Florida, Orlando, all in Computer Science. He is currently a Professor
of Computer Science and Engineering and also the Founding Director of the Center for Research in Wireless Mobility and Networking
(CReWMaN) at the University of Texas at Arlington (UTA). Prior to 1999, he was a professor of Computer Science at the University
of North Texas (UNT), Denton where he founded the Center for Research in Wireless Computing (CReW) in 1997, and also served
as the Director of the Center for Research in Parallel and Distributed Computing (CRPDC) during 1995–97. Dr. Das is a recipient
of the UNT Student Association's Honor Professor Award in 1991 and 1997 for best teaching and scholarly research; UNT's Developing
Scholars Award in 1996 for outstanding research; UTA's Outstanding Faculty Research Award in Computer Science in 2001 and
2003; and the UTA College of Engineering Research Excellence Award in 2003. He is also frequently invited as a keynote speaker
at international conferences and symposia.
Dr. Das' current research interests include mobile wireless communications, resource and mobility management in wireless networks,
mobile and pervasive computing, wireless multimedia, ad hoc and sensor networks, mobile internet architectures and protocols,
distributed and grid computing, performance modeling and simulation. He has published over 350 research papers in these areas
in international journals and conferences, directed numerous industry and government funded projects, and holds five US patents
in wireless mobile networks. He received four Best Paper Awards in the ACM MobiCom'99, ICOIN'01, ACM MSWiM'00, and ACM/IEEE
PADS'97. He as the Editor in Chief of the Pervasive and Mobile Computing (PMC) journal and also as an Associate Editor of
IEEE Transactions on Mobile Computing, ACM/Kluwer Wireless Networks, Parallel Processing Letters, Journal of Parallel, Distributed
and Emerging Systems. He served as General Chair of IEEE WoWMoM'05, PerCom'04, IWDC'04, MASCOTS'02, ACM WoWMoM'00-02; General
Vice Chair of IEEE PerCom'03, ACM MobiCom'00 and IEEE HiPC'00-01; Program Chair of IWDC'02, WoWMoM'98-99; TPC Vice Chair of
ICPADS'02; and as TPC member of numerous IEEE and ACM conferences. He is Vice Chair of the IEEE Computer Society's TCPP and
TCCC Executive Committees. 相似文献
30.
Animesh Roy Tamaghna Acharya Sipra Das Bit 《International Journal of Communication Systems》2020,33(4)
Delay/disruption tolerant networks (DTNs) are potentially applicable in the challenged scenarios like post‐disaster environments. In such networks, data forwarding generally relies on the mutual cooperation of the nodes. However, in reality, despite the availability of necessary resources for data forwarding, a node could misbehave by dropping messages received from other nodes with whom it has no strong social ties. Such a node is called a socially selfish node, which would cause a poor delivery ratio in the network. In this paper, we aim to address the problem of multicast data forwarding in the presence of such selfish nodes, by means of efficient relay selection in DTNs. First, we define a realistic reputation model, in contrast to existing models, to define the socially selfish/misbehaving nodes in the network. Further, a game‐theoretic analysis is carried out that implies data forwarding cost is also an influential parameter in handling selfishness/misbehavior. Subsequently, the problem is formulated as a constrained optimization problem, which is NP hard. Therefore, a heuristic is proposed by combining the reputation of a node and the cost of message forwarding to appropriately identify relay nodes, thus improve the performance of the multicast message delivery in the network. We utilize a social metric, centrality to minimize the message forwarding cost in terms of the number of relay nodes. Finally, the comparative performance evaluation in ONE simulator with practical scenarios shows the superiority of the proposed scheme over the other prominent schemes. 相似文献