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81.
Tao Zhang Eric van den Berg Sunil Madhani Ashutosh Dutta Shantidev Mohanti 《Wireless Networks》2007,13(5):617-633
Mobile users and devices want to discover and share a growing range of information as the processing and storage capabilities
of mobile devices grow. For example, users want to discover nearby networks, and location-based or time-sensitive user information
contents. A mobile device may want to discover neighboring networks and the parameters required to access these networks so
that it can intelligently decide which networks to use next, and use its existing network connection to authenticate with
selected neighboring networks before it moves into the coverage areas of the selected networks. This can significantly reduce
handoff delays. Existing service discovery frameworks are not effective for such neighboring network discovery or for discovering
dynamic, location- or time-sensitive user information contents. This paper describes and evaluates a new approach—Mobile Information
Services enabled by Mobile Publishing (MIS-MP)—for real time collection, discovery, and sharing of network and user information.
With MIS-MP, mobiles take full advantage of the wealth of information they can accumulate during their routine mobility and
use of networks to help each other to discover the information they want when and where they want it. This is accomplished
by mobiles publishing the information they collect about the networks they visited, and the user information contents they
learned or used, to make the information available to other mobiles. This paper presents analytical models and simulation
results to evaluate the feasibility and performance of MIS-MP. It also describes a testbed implementation of MIS-MP and some
of the lessons we learned.
Tao Zhang is Director of Mobile Networking Research Group at Telcordia Technologies, Piscataway, New Jersey, USA. He develops and directs
research and advanced development programs in mobile networking and applications, including mobility and applications across
heterogeneous radio networks, mobile information services, vehicular networking, mobile peer-to-peer applications, sensor
networking and applications, and collaborative networking .Dr. Zhang’s work has led to several new commercial products. He
co-authored the book “IP-Based Next Generation Wireless Networks” published by John Wiley & Sons in 2004. He initiated the International Conference on Collaborative Computing: Networking,
Applications, and Worksharing (CollaborateCom), and has been serving in various roles for it. Dr. Zhang holds 4 U.S. patents,
with over 25 more pending. He received the 2000 Telcordia CEO Award (for most exceptional teams and individuals who have achieved
a significant business success) and 2002 SAIC’s Executive Science and Technology Council Publication Prize.
Eric van den Berg received his Ph.D. in Applied Mathematics from Cornell University in 1999. After obtaining his degree, he joined Telcordia
Technologies, where he is a Research Scientist in Applied Research Department. His research interests include traffic modeling
and performance analysis of IP- and wireless networks. He received the 2000 Telcordia CEO Award (for most exceptional individuals
and teams who have achieved a significant business success) and the 2002 SAIC Executive Science and Technology Council Publication
Prize.
Sunil Madhani is a Distinguished MTS with Motorola where he manages the IP Realization team in Mobile Device Technology Office. He aims
at working on unconventional and disruptive IP technologies. His current research focus is on convergent networks, dynamic
mobility management and fast handoff in secured/seamless wireless LAN/WAN roaming. His past research includes registration/configuration
protocols in wireless environment, application layer mobility management, secured Mobile IP, managed DOS attack sensor and
TCP/IP boosters. Sunil Madhani holds MS (2002) in Engineering Management & System from Columbia University and MS (1997) in
Computer Science from State University of New York. 相似文献
82.
Text extraction and document image segmentation using matched wavelets and MRF model. 总被引:1,自引:0,他引:1
Sunil Kumar Rajat Gupta Nitin Khanna Santanu Chaudhury Shiv Dutt Joshi 《IEEE transactions on image processing》2007,16(8):2117-2128
In this paper, we have proposed a novel scheme for the extraction of textual areas of an image using globally matched wavelet filters. A clustering-based technique has been devised for estim ating globally matched wavelet filters using a collection of groundtruth images. We have extended our text extraction scheme for the segmentation of document images into text, background, and picture components (which include graphics and continuous tone images). Multiple, two-class Fisher classifiers have been used for this purpose. We also exploit contextual information by using a Markov random field formulation-based pixel labeling scheme for refinement of the segmentation results. Experimental results have established effectiveness of our approach. 相似文献
83.
Galiveeti Hemakumar Reddy Malepati Krishnmurthy Kiran Pulumithi Sunil Kumar Arup Kumar Goswami Nalin B. Dev Choudhury 《电力部件与系统》2019,47(19-20):1791-1804
AbstractThe equipment failures are highly uncertain in nature and simple average failure rate will not reflect this uncertainty. The uncertainty level further increases in reliability evaluation due to the integration of wind farm (WF) because of the intermittent nature of wind speed and random charging patterns of plug-in electric vehicles (PEVs). In this work, the uncertain variables in the distribution system (failure rate, repair time, WF output, PEVs charging and system load factor) are represented as fuzzy numbers to handle the uncertainty. The available uncertain data are used to find the probability distribution function (PDF) of that parameter and is converted into fuzzy membership function using transformation techniques. Failure rate of equipment is converted into failure probability using Monte Carlo simulation (MCS) method. Sampling method is applied to create the PDF of a variable which has average value. Fuzzy severity index (FSI) is proposed to find the importance of an equipment on reliability and is evaluated by measuring the fuzzy distance between the fuzzy reliability indices. The proposed assessment method is validated on modified RBTS bus 2 by comparing with analytical and MCS methods. The proposed method has been tested with integration of WFs and PEVs. 相似文献
84.
Sharmistha Swain Brian D. Wardlow Sunil Narumalani Donald C. Rundquist Michael J. Hayes 《International journal of remote sensing》2013,34(8):2814-2828
Understanding the relationships between root zone soil moisture and vegetation spectral signals will enhance our ability to manage water resources and monitor drought-related stress in vegetation. In this article, the relationships between vegetation indices (VIs) and in situ soil moisture under maize and soybean canopies were analysed using close-range reflectance data acquired at a rainfed cropland site in the US Corn Belt. Because of the deep rooting depths of maize plants, maize-based VIs exhibited significant correlations with soil moisture at a depth of 100 cm (P < 0.01) and kept soil moisture memory for a long period of time (45 days). Among the VIs applied to maize, the chrolophyll red-edge index (CIred-edge) correlated best with the concurrent soil moisture at 100 cm depth (P < 0.01) for up to 20 day lag periods. The same index showed a significant correlation with soil moisture at a 50 cm depth for lag periods from 10 (P < 0.05) to 60 days (P < 0.01). VIs applied to soybean resulted in statistically significant correlations with soil moisture at the shallower 10 and 25 cm depths, and the correlation coefficients declined with increasing depths. As opposed to maize, soybean held a shorter soil moisture memory as the correlations for all VIs versus soil moisture at 10 cm depth were strongest for the 5 day lag period. Wide dynamic range VI and normalized difference VI performed better in characterizing soil moisture at the 10 and 25 cm depths under soybean canopies when compared with enhanced VI and CIred-edge. 相似文献
85.
86.
Anil G. Panda Malhari D. Bhor Sunil S. Ekbote Bhalchandra M. Bhanage 《Catalysis Letters》2009,131(3-4):649-655
Polyethylene glycol based diphosphinite ligands and their Wilkinson type Rh-polymeric carbonyl complexes were prepared for homogeneous hydroformylation of styrenes. The effect of reaction variables such as temperature, pressure, P/Rh ratio, Substrate/Rh ratio, phosphine and phosphinite ligands on the activity and selectivity performance were discussed in detail. The catalyst showed a high rate of reaction, TON and tunable regioselectivity depending upon reaction conditions as compared to conventional Rh-phosphine based catalysts. 相似文献
87.
The author examines the historical role of Euro-American psychology in constructing Orientalist representations of the natives who were colonized by the European colonial powers. In particular, the author demonstrates how the power to represent the non-Western "Other" has always resided, and still continues to reside, primarily with psychologists working in Europe and America. It is argued that the theoretical frameworks that are used to represent non-Westerners in contemporary times continue to emerge from Euro-American psychology. Finally, the author discusses how non-Western psychologists internalized these Orientalist images and how such a move has led to a virtual abandonment of pursuing "native" forms of indigenous psychologies in Third World psychology departments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Shah M. Yunus Sunil Saigal Robert D. Cook 《International journal for numerical methods in engineering》1989,28(4):785-800
A set of three new hybrid elements with rotational degrees-of-freedom (d.o.f.'s) is introduced. The solid, 8-node, hexahedron element is developed for solving three-dimensional elasticity problems. This element has three translational and three rotational d.o.f.'s at each node and is based on a 42-parameter. three-dimensional stress field in the natural convected co-ordinate system. For two-dimensional, plane elasticity problems, an improved triangular hybrid element and a quadrilateral hybrid element are presented. These elements use two translational and one rotational d.o.f. at each node. Three different sets of five-parameter stress fields defined in a natural convected co-ordinate system for the entire element are used for the mixed triangular element. The mixed quadrilateral element is based on a nine-parameter complete linear stress field in natural space. The midside translational d.o.f.'s are expressed in terms of the corner nodal translations and rotations using appropriate transformations. The stiffness matrix is derived based on the Hellinger–Reissner variational principle. The elements pass the patch test and demonstrate an improved performance over the existing elements for prescribed test examples. 相似文献
89.
The combined effect of magnetic field and rotation on thermosolutal instability of a compressible fluid in porous medium is considered. The system is found to be stable for (Cp/g)β < 1 where Cp, β, and g stand for specific heat at constant pressure, uniform adverse temperature gradient, and acceleration due to gravity, respectively. The stable solute gradient, magnetic field, and rotation introduce oscillatory modes in the system for (Cp/g)β > 1, which were nonexistent in their absence. For stationary convection, the stable solute gradient and rotation have a stabilizing effect on the system for (Cp/g)β > 1. In the presence of rotation, the magnetic field has a stabilizing (or destabilizing) effect, and the medium permeability has a destabilizing (or stabilizing) effect under certain condition, whereas in the absence of rotation, the magnetic field and rotation have stabilizing and destabilizing effects for (Cp/g)β > 1, respectively, on the system. The sufficient conditions for the existence of overs-lability are obtained. 相似文献
90.
Kesavan Sunil K. Reddy Narender P. Yazdani-Ardakani Saeed 《IEEE transactions on bio-medical engineering》1986,(9):898-900
Water irrigation devices (WID's) are widely used in homes and dental clinics across the country for oral hygiene. There have been several reported cases of tissue damage with the use of these devices. In the present investigation, two commercially available oral water irrigation devices were evaluated using engineering techniques. The impact thrusts delivered by these devices were measured at different control settings. Both of the tested commercial oral water irrigation devices were found to exert abnormally high thrust which could cause serious damage to the sulcular epithelium and the underlying tissues. These pressures are far in excess of the pressure intensity necessary to perform the cleaning action. Moreover, the existing designs using reciprocating pumps are unsafe and are potentially dangerous, particularly with small diameter tips. 相似文献