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排序方式: 共有646条查询结果,搜索用时 15 毫秒
51.
Zhangxi Lin Sathya Ramanathan Huimin Zhao 《Information Systems and E-Business Management》2005,3(3):221-242
Web services technology is becoming an important technological trend in Web application development and integration. Based on open standards, such as SOAP, WSDL, and UDDI, Web services allow Web-based applications to communicate with each other through standardized XML messaging and to form loosely coupled distributed systems. Although the open feature of Web services benefits service providers in servicing consumers, the unlimited computing resources access of Web services to network bandwidth, storage throughput, and CPU time may lead to overexploitation of the resources when applications based on the Web services technology are widely accepted. Therefore, it is critical to optimize the operation of Web services, subject to the QoS requirements of service requests, to assure the total benefits of the service providers and the service consumers. This paper proposes a usage-based dynamic pricing approach to optimizing resource allocation of Web services in the principle of economics, and reports on a pilot implementation demonstrating the technical feasibility of the proposed approach.
相似文献
Huimin ZhaoEmail: |
52.
We present a novel approach to optimally retarget videos for varied displays with differing aspect ratios by preserving salient scene content discovered via eye tracking. Our algorithm performs editing with cut, pan and zoom operations by optimizing the path of a cropping window within the original video while seeking to (i) preserve salient regions, and (ii) adhere to the principles of cinematography. Our approach is (a) content agnostic as the same methodology is employed to re‐edit a wide‐angle video recording or a close‐up movie sequence captured with a static or moving camera, and (b) independent of video length and can in principle re‐edit an entire movie in one shot. Our algorithm consists of two steps. The first step employs gaze transition cues to detect time stamps where new cuts are to be introduced in the original video via dynamic programming. A subsequent step optimizes the cropping window path (to create pan and zoom effects), while accounting for the original and new cuts. The cropping window path is designed to include maximum gaze information, and is composed of piecewise constant, linear and parabolic segments. It is obtained via L(1) regularized convex optimization which ensures a smooth viewing experience. We test our approach on a wide variety of videos and demonstrate significant improvement over the state‐of‐the‐art, both in terms of computational complexity and qualitative aspects. A study performed with 16 users confirms that our approach results in a superior viewing experience as compared to gaze driven re‐editing [ JSSH15 ] and letterboxing methods, especially for wide‐angle static camera recordings. 相似文献
53.
Given a planar point set sampled from an object boundary, the process of approximating the original shape is called curve reconstruction. In this paper, a novel non‐parametric curve reconstruction algorithm based on Delaunay triangulation has been proposed and it has been theoretically proved that the proposed method reconstructs the original curve under ε‐sampling. Starting from an initial Delaunay seed edge, the algorithm proceeds by finding an appropriate neighbouring point and adding an edge between them. Experimental results show that the proposed algorithm is capable of reconstructing curves with different features like sharp corners, outliers, multiple objects, objects with holes, etc. The proposed method also works for open curves. Based on a study by a few users, the paper also discusses an application of the proposed algorithm for reconstructing hand drawn skip stroke sketches, which will be useful in various sketch based interfaces. 相似文献
54.
Manoj Parameswaran Xia Zhao Andrew B. Whinston Fang Fang 《Computer》2007,40(1):40-44
The growing proliferation of malware is raising doubts about the Internet's future. Security measures primarily target inbound traffic, but service providers have no incentive to stop attacks and spam at the source. A proposed certification scheme motivates providers to control outgoing traffic, efficiently increasing overall security while preserving the Internet's open, decentralized structure 相似文献
55.
Daxin Jiang Jian Pei Murali Ramanathan Chuan Lin Chun Tang Aidong Zhang 《Knowledge and Information Systems》2007,13(3):305-335
Extensive studies have shown that mining microarray data sets is important in bioinformatics research and biomedical applications.
In this paper, we explore a novel type of gene–sample–time microarray data sets that records the expression levels of various
genes under a set of samples during a series of time points. In particular, we propose the mining of coherent gene clusters from such data sets. Each cluster contains a subset of genes and a subset of samples such that the genes are coherent on
the samples along the time series. The coherent gene clusters may identify the samples corresponding to some phenotypes (e.g.,
diseases), and suggest the candidate genes correlated to the phenotypes. We present two efficient algorithms, namely the Sample-Gene Search and the Gene–Sample Search, to mine the complete set of coherent gene clusters. We empirically evaluate the performance of our approaches on both a
real microarray data set and synthetic data sets. The test results have shown that our approaches are both efficient and effective
to find meaningful coherent gene clusters.
Daxin Jiang received the Ph.D. degree in computer science and engineering from the State University of New York at Buffalo in 2005. He
received the B.S. degree in computer science from the University of Science and Technology of China. From 1998 to 2000, he
was a M.S. student in Software Institute, Chinese Academy of Sciences. He is currently an assistant professor at the School
of Computer Engineering, Nanyang Technology University, Singapore. His research interests include data mining, bioinformatics,
machine learning, and information retrieval.
Jian Pei received the Ph.D. degree in computing science from Simon Fraser University, Canada, in 2002, under Dr. Jiawei Han's supervision.
He also received the B.Eng. and the M.Eng. degrees from Shanghai Jiao Tong University, China, in 1991 and 1993, respectively,
both in Computer Science. He is currently an assistant professor of computing science at Simon Fraser University. His research
interests include developing effective and efficient data analysis techniques for novel data intensive applications. He is
currently interested in various techniques of data mining, data warehousing, online analytical processing, and database systems,
as well as their applications in bioinformatics. His current research is supported in part by the Natural Sciences and Engineering
Research Council of Canada (NSERC) and the National Science Foundation (NSF) of the United States. Since 2000, he has published
over 70 research papers in refereed journals, conferences, and workshops, has served in the organization committees and the
program committees of over 60 international conferences and workshops, and has been a reviewer for some leading academic journals.
He is a member of the ACM, the ACM SIGMOD, and the ACM SIGKDD.
Murali Ramanathan is an associate professor of pharmaceutical sciences and neurology. He received the B.Tech. (Honors) in chemical engineering
from the Indian Institute of Technology, India, in 1983. After a 4-year stint in the chemical industry, he obtained the M.S.
degree in chemical engineering from Iowa State University, Ames, IA, in 1987, and the Ph.D. degree in bioengineering from
the University of California-San Francisco and University of California-Berkeley Joint Program in Bioengineering in 1994.
Dr. Ramanathan research interests are primarily focused on the treatment of multiple sclerosis (MS), an inflammatory-demyelinating
disease of the central nervous system that affects over 1 million patients worldwide. MS is a complex, variable disease that
causes physical and cognitive disability and nearly 50% of patients diagnosed with MS are unable to walk after 15 years. The
etiology and pathogenesis of MS remains poorly understood. Dr. Ramanathan's research interests include stochastic modeling
of pharmaceutical systems and novel approaches to analyzing and using genetic and genomic data for improving patient care
and optimizing therapy.
Chuan Lin is currently a Ph.D. student in the Department of Computer Science and Engineering, State University of New York at Buffalo.
She received the B.E. and the M.S. degrees in computer science and technology from Tsinghua University in China. Her research
interests include bioinformatics, data mining, and machine learning.
Chun Tang received the B.S. and M.S. degrees from Peking University, China, in 1996 and 1999, respectively, and the Ph.D. degree from
State University of New York at Buffalo, USA, in 2005, all in computer science. Currently, she is a postdoctoral associate
of Center for Medical Informatics, Yale University. Her research interests include bioinformatics, data mining, machine learning,
database, and information retrieval.
Aidong Zhang received the Ph.D. degree in computer science from Purdue University, West Lafayette, Indiana, in 1994. She was an assistant
professor from 1994 to 1999, an associate professor from 1999 to 2002, and has been a professor since 2002 in the Department
of Computer Science and Engineering at State University of New York at Buffalo. Her research interests include multimedia
systems, content-based image retrieval, bioinformatics, and data mining. She is an author of over 140 research publications
in these areas. Dr. Zhang's research has been funded by NSF, NIH, NIMA, and Xerox. Zhang serves on the editorial boards of
International Journal of Bioinformatics Research and Applications (IJBRA), ACM Multimedia Systems, International Journal of Multimedia Tools and Applications, and International Journal of Distributed and Parallel Databases. She was the editor for ACM SIGMOD DiSC (Digital Symposium Collection) from 2001 to 2003. She was co-chair of the technical
program committee for ACM Multimedia in 2001. She has also served on various conference program committees. Dr. Zhang is a
recipient of the National Science Foundation CAREER award and SUNY Chancellor's Research Recognition award. 相似文献
56.
Chen K Huzil JT Freedman H Ramachandran P Antoniou A Tuszynski JA Kurgan L 《Journal of molecular graphics & modelling》2008,27(4):497-505
Microtubules are involved in numerous cellular processes including chromosome segregation during mitosis and, as a result, their constituent protein, tubulin, has become a successful target of several chemotherapeutic drugs. In general, these drugs bind indiscriminately to tubulin within both cancerous and healthy cells, resulting in unwanted side effects. However, differences between beta-tubulin isotypes expressed in a wide range of cell types may aid in the development of anti-tubulin drugs having increased specificity for only certain types of cells. Here, we describe a digital signal processing (DSP) method that is capable of predicting hot spots for the tubulin family of proteins as well as determining relative differences in binding affinities to these hot spots based only on the primary sequence of 10 human tubulin isotypes. Due to the fact that several drug binding sites have already been characterized within beta-tubulin, we are able to correlate hot spots with the binding sites for known chemotherapy drugs. We have also verified the accuracy of this method using the correlation between the binding affinities of characterized drugs and the tubulin isotypes. Additionally, the DSP method enables the rapid estimation of relative differences in binding affinities within the binding sites of tubulin isotypes that are yet to be experimentally determined. 相似文献
57.
T. Ramanathan M. A. Muthumanickam K. Subramanian 《Materials and Manufacturing Processes》2000,15(6):845-852
The influence of loading rate, span-to-thickness ratio and fiber volume fraction on composites was studied by three-point bend test on glass fiber reinforced in polyester composite laminate fabricated by compression moulding method. For lower L/h ratio, shear fracture was observed. Tensile fracture was observed for the specimen having higher L/h ratio irrespective of loading rate. Shear fracture dominates at high loading rates. This behavior was interpreted as being due to the fact that the increase in loading rate increases the brittleness of materials, subsequently increasing the defect sensitivity and leading to shear fracture. 相似文献
58.
N. Parameswaran P. E. Heizmann M. Kufner W. Ginzel G. Stegmann O. Liiri A. Dosoudü H. Willeitmer U. Tuovinen K. A. Sorg L. Wagner A. Dosoudil H. Fickler H. Kilpeläinen K. Rügge 《Holz als Roh- und Werkstoff》1968,26(7):271-275
Ohne Zusammenfassung 相似文献
59.
K Ramanathan TH Michael GJ Jiang H Hiel PA Fuchs 《Canadian Metallurgical Quarterly》1999,283(5399):215-217
Cochlear frequency selectivity in lower vertebrates arises in part from electrical tuning intrinsic to the sensory hair cells. The resonant frequency is determined largely by the gating kinetics of calcium-activated potassium (BK) channels encoded by the slo gene. Alternative splicing of slo from chick cochlea generated kinetically distinct BK channels. Combination with accessory beta subunits slowed the gating kinetics of alpha splice variants but preserved relative differences between them. In situ hybridization showed that the beta subunit is preferentially expressed by low-frequency (apical) hair cells in the avian cochlea. Interaction of beta with alpha splice variants could provide the kinetic range needed for electrical tuning of cochlear hair cells. 相似文献
60.