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81.
82.
Hybrid Model to Detect Zero Quantized DCT Coefficients in H.264 总被引:2,自引:0,他引:2
Hanli Wang Sam Kwong 《Multimedia, IEEE Transactions on》2007,9(4):728-735
In H.264 coding, there are a large number of discrete cosine transform (DCT) coefficients of the prediction residue which are quantized to zeros. Therefore, it is desired to design a method which can early detect zero quantized DCT coefficients (ZQDCT) before implementing DCT and quantization (Q) and thus reduce redundant computations for H.264 coding. To achieve this, a hybrid model is proposed in this paper in order to predict ZQDCT coefficients. First, the Gaussian distribution is applied to study the integer DCT coefficients in H.264 and hence an adaptive scheme with multiple thresholds is derived to realize different types of DCT and Q implementations. Then the adaptive scheme is further optimized by considering a more efficient condition to sufficiently detect all-zero DCT blocks. As a result, a hybrid model is developed. Compared with other methods in the literature, the proposed hybrid model is able to detect more ZQDCT coefficients and hence reduce more computations for H.264 encoding. It is shown by experimental results that the proposed hybrid model can achieve the best performance in reducing computations and obtain almost the same rate-distortion (R-D) performance as the original encoder in the H.264 reference software JM9.5 相似文献
83.
Han Jung KimAuthor VitaeHee-Jin SohnAuthor Vitae Sanghun KimAuthor Vitae Sam Nyung YiAuthor VitaeDong Han HaAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):990-993
We report a molecular sensing method based on changes in the electrical conductance of lithographically defined gold nanoparticle (NP) arrays immersed in an analyte solution. As the closely spaced NPs are enlarged due to the analyte-mediated deposition of gold ions onto their surfaces, the conductance increases steeply near the critical time (tc) at which conducting pathways begin to form in the NP arrays. tc decreases with increasing analyte concentration in the solution. The temperature dependence of the conductance of the modified NP arrays confirms the good electrical contacts established between the newly formed nanoclusters on the NP surfaces. Our results demonstrate that the electrical conductance through metal NP arrays can be employed as a sensitive and reliable analytical signal for NP-based sensors, which do not require any post-processing for the formation of electrical contacts between the NPs. 相似文献
84.
A range query finds the aggregated values over all selected cells of an online analytical processing (OLAP) data cube where
the selection is specified by the ranges of contiguous values for each dimension. An important issue in reality is how to
preserve the confidential information in individual data cells while still providing an accurate estimation of the original
aggregated values for range queries. In this paper, we propose an effective solution, called the zero-sum method, to this
problem. We derive theoretical formulas to analyse the performance of our method. Empirical experiments are also carried out
by using analytical processing benchmark (APB) dataset from the OLAP Council. Various parameters, such as the privacy factor
and the accuracy factor, have been considered and tested in the experiments. Finally, our experimental results show that there
is a trade-off between privacy preservation and range query accuracy, and the zero-sum method has fulfilled three design goals:
security, accuracy, and accessibility.
Sam Y. Sung is an Associate Professor in the Department of Computer Science, School of Computing, National University of Singapore. He
received a B.Sc. from the National Taiwan University in 1973, the M.Sc. and Ph.D. in computer science from the University
of Minnesota in 1977 and 1983, respectively. He was with the University of Oklahoma and University of Memphis in the United
States before joining the National University of Singapore. His research interests include information retrieval, data mining,
pictorial databases and mobile computing. He has published more than 80 papers in various conferences and journals, including
IEEE Transaction on Software Engineering, IEEE Transaction on Knowledge & Data Engineering, etc.
Yao Liu received the B.E. degree in computer science and technology from Peking University in 1996 and the MS. degree from the Software
Institute of the Chinese Science Academy in 1999. Currently, she is a Ph.D. candidate in the Department of Computer Science
at the National University of Singapore. Her research interests include data warehousing, database security, data mining and
high-speed networking.
Hui Xiong received the B.E. degree in Automation from the University of Science and Technology of China, Hefei, China, in 1995, the
M.S. degree in Computer Science from the National University of Singapore, Singapore, in 2000, and the Ph.D. degree in Computer
Science from the University of Minnesota, Minneapolis, MN, USA, in 2005. He is currently an Assistant Professor of Computer
Information Systems in the Management Science & Information Systems Department at Rutgers University, NJ, USA. His research
interests include data mining, databases, and statistical computing with applications in bioinformatics, database security,
and self-managing systems. He is a member of the IEEE Computer Society and the ACM.
Peter A. Ng is currently the Chairperson and Professor of Computer Science at the University of Texas—Pan American. He received his Ph.D.
from the University of Texas–Austin in 1974. Previously, he had served as the Vice President at the Fudan International Institute
for Information Science and Technology, Shanghai, China, from 1999 to 2002, and the Executive Director for the Global e-Learning
Project at the University of Nebraska at Omaha, 2000–2003. He was appointed as an Advisory Professor of Computer Science at
Fudan University, Shanghai, China in 1999. His recent research focuses on document and information-based processing, retrieval
and management. He has published many journal and conference articles in this area. He had served as the Editor-in-Chief for
the Journal on Systems Integration (1991–2001) and as Advisory Editor for the Data and Knowledge Engineering Journal since
1989. 相似文献
85.
Sam J. Cipolla 《Computer Physics Communications》2008,179(8):616
The formatting of the M-shell atomic parameters imbedded in file XCSC.H in ISICS has been corrected. The problem only affected cross section calculations for Uranium and heavier elements. The corrected version of ISICS has been re-compiled and is now available.
New version program summary
Program title: ISICSCatalogue identifier: ADDS_v3_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADDS_v3_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 4645No. of bytes in distributed program, including test data, etc.: 106 731Distribution format: tar.gzProgramming language: C++Computer: 80486 or higher-level PCsOperating system: WINDOWS 98 through WINDOWS XPClassification: 16.7Does the new version supersede the previous version?: YesNature of problem: Ionization and X-ray production cross section calculations for ion-atom collisions.Solution method: Numerical integration of form factor using a logarithmic transform and Gaussian quadrature, plus exact integration limits.Reasons for new version: The formatting of the M-shell atomic parameters involving cross section calculations for Uranium and heavier elements needed to be corrected.Summary of revisions: The affected file XCSC.H in ISICS has been corrected and ISICS has been recompiled.Restrictions: The consumed CPU time increases with the atomic shell (K, L, M), but execution is still very fast.Running time: This depends on which shell and the number of different energies to be used in the calculation. For example, to calculate K-shell cross sections for protons striking carbon for 19 different proton energies it took less than 10 s; to calculate M-shell cross sections for protons on gold for 21 proton energies it took 4.2 min. 相似文献86.
Keng Peng Tee Author Vitae Shuzhi Sam Ge Author Vitae Eng Hock Tay Author Vitae 《Automatica》2009,45(4):918-119
In this paper, we present control designs for single-input single-output (SISO) nonlinear systems in strict feedback form with an output constraint. To prevent constraint violation, we employ a Barrier Lyapunov Function, which grows to infinity when its arguments approach some limits. By ensuring boundedness of the Barrier Lyapunov Function in the closed loop, we ensure that those limits are not transgressed. Besides the nominal case where full knowledge of the plant is available, we also tackle scenarios wherein parametric uncertainties are present. Asymptotic tracking is achieved without violation of the constraint, and all closed loop signals remain bounded, under a mild condition on the initial output. Furthermore, we explore the use of an Asymmetric Barrier Lyapunov Function as a generalized approach that relaxes the requirements on the initial conditions. We also compare our control with one that is based on a Quadratic Lyapunov Function, and we show that our control requires less restrictive initial conditions. A numerical example is provided to illustrate the performance of the proposed control. 相似文献
87.
Color-defective vision and computer graphics displays 总被引:1,自引:0,他引:1
A color space defined by the fundamental spectral sensitivity functions of the human visual system is used to assist in the design of computer graphics displays for color-deficient users. The functions are derived in terms of the CIE standard observer color-matching functions. The Farnsworth-Munsell 100-hue test, a widely used color vision test administered using physical color samples, is then implemented on a digitally controlled color television monitor. The flexibility of this computer graphics medium is then used to extend the Farnsworth-Munsell test in a way that improves the specificity of the diagnoses rendered by the test. The issue of how the world appears to color-deficient observers is addressed, and a full-color image is modified to represent a color-defective view of the scene. Specific guidelines are offered for the design of computer graphics displays that will accommodate almost all color-deficient users 相似文献
88.
An immersable pressure-capacitance gauge has been designed which has a linearity over a pressure range, is non-magnetic and has twice the sensitivity of a single diaphragm 相似文献
89.
90.
Gary Greenberg 《Computers and the Humanities》1991,25(5):267-273
This paper describes how the creative arts can provide an alternative approach to computer programming that may benefit students in the humanities in general. It focuses on creative arts projects using text, graphics and music that allow students to encounter the same programming concepts from a number of different perspectives. It also discusses the importance of symbolic programming for the arts and how the creative arts can provide a particularly rich environment for developing approaches to object-oriented programming.Gary Greenberg received his B. A. and M. A. in Music from Stanford University and his Ph.D. in Music from Harvard University. His activities include creating compositional programming environments (Composing with Performer Objects, The Proceedings of the 1988 International Computer Music Conference) and developing ways of using the computer to learn about music through compositional activities (Music Learning-Compositional Thinking). He is currently manager of the Northwestern University Advanced Technology Group where he coordinates the Computer Media Studio and is exploring ways to use computer multimedia in instruction and research. 相似文献