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81.
82.
In Bayesian machine learning, conjugate priors are popular, mostly due to mathematical convenience. In this paper, we show
that there are deeper reasons for choosing a conjugate prior. Specifically, we formulate the conjugate prior in the form of
Bregman divergence and show that it is the inherent geometry of conjugate priors that makes them appropriate and intuitive.
This geometric interpretation allows one to view the hyperparameters of conjugate priors as the effective sample points, thus providing additional intuition. We use this geometric understanding of conjugate priors to derive the
hyperparameters and expression of the prior used to couple the generative and discriminative components of a hybrid model
for semi-supervised learning. 相似文献
83.
In this paper we classify the complexity of several problems based on Abelian permutation groups and linear congruences using
logspace counting classes. The problems we consider were defined by McKenzie & Cook (1987). 相似文献
84.
Vishal BalouriaAuthor Vitae Arvind KumarAuthor VitaeA. SinghAuthor Vitae S. SamantaAuthor VitaeA.K. DebnathAuthor Vitae Aman MahajanAuthor VitaeR.K. BediAuthor Vitae D.K. AswalAuthor Vitae S.K. GuptaAuthor VitaeJ.V. YakhmiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,157(2):466-472
The conductometric gas sensing characteristics of Cr2O3 thin films - prepared by electron-beam deposition of Cr films on quartz substrate followed by oxygen annealing - have been investigated for a host of gases (CH4, CO, NO2, Cl2, NH3 and H2S) as a function of operating temperature (between 30 and 300 °C) and gas concentration (1-30 ppm). We demonstrate that these films are highly selective to H2S at an operating temperature of 100 °C, while at 220 °C the films become selective to Cl2. This result has been explained on the basis of depletion of chemisorbed oxygen from the surface of films due to temperature and/or interaction with Cl2/H2S, which is supported experimentally by carrying out the work function measurements using Kelvin probe method. The temperature dependent selectivity of Cr2O3 thin films provides a flexibility to use same film for the sensing of Cl2 as well as H2S. 相似文献
85.
In recent years, there has been a growing interest in wireless sensor networks. One of the major issues in wireless sensor network is developing an energy-efficient clustering protocol. Hierarchical clustering algorithms are very important in increasing the network’s life time. Each clustering algorithm is composed of two phases, the setup phase and steady state phase. The hot point in these algorithms is the cluster head selection. In this paper, we study the impact of heterogeneity of nodes in terms of their energy in wireless sensor networks that are hierarchically clustered. We assume that a percentage of the population of sensor nodes is equipped with the additional energy resources. We also assume that the sensor nodes are randomly distributed and are not mobile, the coordinates of the sink and the dimensions of the sensor field are known. Homogeneous clustering protocols assume that all the sensor nodes are equipped with the same amount of energy and as a result, they cannot take the advantage of the presence of node heterogeneity. Adapting this approach, we introduce an energy efficient heterogeneous clustered scheme for wireless sensor networks based on weighted election probabilities of each node to become a cluster head according to the residual energy in each node. Finally, the simulation results demonstrate that our proposed heterogeneous clustering approach is more effective in prolonging the network lifetime compared with LEACH. 相似文献
86.
Deepak Kumar Patel Devashree Tripathy Chitaranjan Tripathy 《Engineering with Computers》2016,32(2):173-188
Grid computing has emerged a new field, distinguished from conventional distributed computing. It focuses on large-scale resource sharing, innovative applications and in some cases, high performance orientation. The Grid serves as a comprehensive and complete system for organizations by which the maximum utilization of resources is achieved. The load balancing is a process which involves the resource management and an effective load distribution among the resources. Therefore, it is considered to be very important in Grid systems. For a Grid, a dynamic, distributed load balancing scheme provides deadline control for tasks. Due to the condition of deadline failure, developing, deploying, and executing long running applications over the grid remains a challenge. So, deadline failure recovery is an essential factor for Grid computing. In this paper, we propose a dynamic distributed load-balancing technique called “Enhanced GridSim with Load balancing based on Deadline Failure Recovery” (EGDFR) for computational Grids with heterogeneous resources. The proposed algorithm EGDFR is an improved version of the existing EGDC in which we perform load balancing by providing a scheduling system which includes the mechanism of recovery from deadline failure of the Gridlets. Extensive simulation experiments are conducted to quantify the performance of the proposed load-balancing strategy on the GridSim platform. Experiments have shown that the proposed system can considerably improve Grid performance in terms of total execution time, percentage gain in execution time, average response time, resubmitted time and throughput. The proposed load-balancing technique gives 7 % better performance than EGDC in case of constant number of resources, whereas in case of constant number of Gridlets, it gives 11 % better performance than EGDC. 相似文献
87.
This paper examines prioritization in a service system and analyzes whether, in the presence of heterogeneous customers who have different needs and a costly sorting process, it pays to prioritize. In particular, in our model, sorting is costly because the task of gathering information to prioritize jobs consumes resources. We investigate a stylized model in which there are two classes of jobs — one whose waiting cost is high, called urgent, and the other whose waiting cost is low, called non-urgent. There are two types of employees, sorters, who collect information on a job and then decide whether it is urgent or non-urgent, and processors, who execute the job or provide the service. We begin by assuming that sorters categorize customers perfectly, and we relax this assumption later in the paper. We optimize two performance metrics, waiting costs (under a given budget) and total costs, and find the conditions under which prioritization is beneficial for these two metrics. 相似文献
88.
Akila Varadarajan Nilesh Patel Bruce Maxim William I. Grosky 《Multimedia Tools and Applications》2008,40(2):211-239
There has been increased interest on the impact of mobile devices such as PDAs and Tablet PCs in introducing new pedagogical
approaches and active learning experiences. We propose an intelligent system that efficiently addresses the inherent subjectivity
in student perception of note taking and information retrieval. We employ the idea of cross indexing the digital ink notes
with matching electronic documents in the repository. Latent Semantic Indexing is used to perform document and page level
indexing. Thus for each retrieved document, the user can go over to the relevant pages that match the query. Techniques to
handle problems such as polysemy (multiple meanings of a word) in large databases, document folding and no match for query
are discussed. We tested our system for its performance, usability and effectiveness in the learning process. The results
from the exploratory studies reveal that the proposed system provides a highly enhanced student learning experience, thereby
facilitating high test scores.
Akila Varadarajan is a Senior Software Engineer at Motorola, IL with the Mobile devices division. Prior joining Motorola, she was a Software development intern at Autodesk, MI and Graduate Research assistant at University of Michigan - Dearborn. She received her MS in Computer Engineering from University of Michigan in 2006 and her BS in Computer Engineering from Madurai Kamaraj University, India in 2003. She is interested in Mobile computing - specifically Human Factors of Mobile Computing, Information retrieval and pattern recognition. Nilesh Patel is Assistant Professor in the department of Computer Science and Engineering at Oakland University, MI. He received his PhD and MS in Computer Science from Wayne State University, MI in 1997 and 1993. He is interested in Multimedia Information Processing - specifically audio and video indexing, retrieval and event detection, Pattern Recognition, Distributed Data Mining in a heterogeneous environment, and Computer Vision with special interest in medical imaging. Dr. Patel has also served in the automotive sector for several years and developed interest in Telematics and Mobile Computing. Bruce Maxim has worked as a software engineer for the past 31 years. He is a member of the Computer and Information Science faculty at the University of Michigan-Dearborn since 1985. He serves as the computing laboratory supervisor and head of the undergraduate programs in Computer Science, Software Engineering, and Information Systems. He has created more than 15 Computer and Information Science courses dealing with software engineering, game design, artificial intelligence, user interface design, web engineering, software quality, and computer programming. He has authored or co-authored four books on programming and software engineering. He has most recently served on the pedagogy subcommittee for Software Engineering 2004 and contributed to the IDGA Game Curriculum Framework 2008 guidelines. William I. Grosky is currently Professor and Chair of the Department of Computer and Information Science at University of Michigan - Dearborn, Dearborn, Michigan. Prior to joining the University of Michigan in 2001, he was Professor and Chair of the Department of Computer Science at Wayne State University, Detroit, Michigan. Before joining Wayne State University in 1976, he was an Assistant Professor in the Department of Information and Computer Science at Georgia Tech, Atlanta, Georgia. He received his B.S. in Mathematics from MIT in 1965, his M.S. in Applied Mathematics from Brown University in 1968, and his Ph.D. in Engineering and Applied Science from Yale University in 1971. 相似文献
William I. GroskyEmail: |
Akila Varadarajan is a Senior Software Engineer at Motorola, IL with the Mobile devices division. Prior joining Motorola, she was a Software development intern at Autodesk, MI and Graduate Research assistant at University of Michigan - Dearborn. She received her MS in Computer Engineering from University of Michigan in 2006 and her BS in Computer Engineering from Madurai Kamaraj University, India in 2003. She is interested in Mobile computing - specifically Human Factors of Mobile Computing, Information retrieval and pattern recognition. Nilesh Patel is Assistant Professor in the department of Computer Science and Engineering at Oakland University, MI. He received his PhD and MS in Computer Science from Wayne State University, MI in 1997 and 1993. He is interested in Multimedia Information Processing - specifically audio and video indexing, retrieval and event detection, Pattern Recognition, Distributed Data Mining in a heterogeneous environment, and Computer Vision with special interest in medical imaging. Dr. Patel has also served in the automotive sector for several years and developed interest in Telematics and Mobile Computing. Bruce Maxim has worked as a software engineer for the past 31 years. He is a member of the Computer and Information Science faculty at the University of Michigan-Dearborn since 1985. He serves as the computing laboratory supervisor and head of the undergraduate programs in Computer Science, Software Engineering, and Information Systems. He has created more than 15 Computer and Information Science courses dealing with software engineering, game design, artificial intelligence, user interface design, web engineering, software quality, and computer programming. He has authored or co-authored four books on programming and software engineering. He has most recently served on the pedagogy subcommittee for Software Engineering 2004 and contributed to the IDGA Game Curriculum Framework 2008 guidelines. William I. Grosky is currently Professor and Chair of the Department of Computer and Information Science at University of Michigan - Dearborn, Dearborn, Michigan. Prior to joining the University of Michigan in 2001, he was Professor and Chair of the Department of Computer Science at Wayne State University, Detroit, Michigan. Before joining Wayne State University in 1976, he was an Assistant Professor in the Department of Information and Computer Science at Georgia Tech, Atlanta, Georgia. He received his B.S. in Mathematics from MIT in 1965, his M.S. in Applied Mathematics from Brown University in 1968, and his Ph.D. in Engineering and Applied Science from Yale University in 1971. 相似文献
89.
90.
beta3GalTs are type II transmembrane proteins that transfer galactose from UDP-Gal donor substrate to acceptor GlcNAc, GalNAc or Gal in beta1-->3-linkage. beta1-->3-linked galactose have been found to be a part of many glycans like glycosphingolipids, core tetrasaccharide of proteoglycans, type 1 chains. The 3-D structure of none of the beta3GalTs is known to date. In this study, the 3-D structures of human beta3GalT I, II, IV, V, VI and beta3GalNAcT I have been modeled using fold-recognition and comparative modeling methods. Residues that constitute the UDP-Gal binding site have been predicted. The models are able to qualitatively rationalize data from the site-directed mutagenesis experiments reported in the literature. Residues likely to be involved in conferring differential acceptor substrate specificity have been predicted by a combination of specificity determining positions prediction (SDPs) and subsequent mapping on the generated 3-D models. 相似文献