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81.
Whilst the space volume of muffler in noise control system is often constrained for maintenance in practical engineering work, the maximization on muffler’s performance becomes important and essential. In this paper, a novel approach genetic algorithms (GAs) based on the principles of natural biological evolution will be used to tackle this optimization of muffler design [M. Mitchell, An Introduction to Genetic Algorithms, The MIT Press, Cambridge, MA, 1996]. Here, the shape optimization of multi-segments muffler coupled with the GA searching technique is presented. The techniques of binary genetic algorithms (BGA) together with the commercial MATLAB package [G. Lindfield, J. Penny, Numerical Method Using Matlab, second ed., Prentice Hall, Englewood Cliffs, NJ, 2000] are applied in GA searching. In addition, a numerical case of pure tone elimination with 2-5 segments on muffler is introduced and fully discussed. To achieve the best optimization in GA, several GA parameters are on trial in various values. Results show that the GA operators, including crossover mutation and elitism, are essential in accuracy. Consequently, results verify that the optimal sound transmission loss at the designed frequency of 500 Hz is exactly maximized. The GA optimization on multi-segments muffler proposed in this study surely provides a quick and correct approach. 相似文献
82.
L.G. Casado I. García T. Csendes V.G. Ruíz 《Journal of Optimization Theory and Applications》2003,118(1):27-43
Based on the investigation carried out in Ref. 1, this paper incorporates new studies about the properties of inclusion functions on subintervals while a branch-and-bound algorithm is solving global optimization problems. It is found that the relative place of the global minimum value within the inclusion function value of the objective function at the current interval indicates mostly whether the given interval is close to a minimizer point. This information is used in a heuristic interval rejection rule that can save a considerable amount of computation. Illustrative examples are discussed and an extended numerical study shows the advantages of the new approach. 相似文献
83.
84.
提出了一种全局优化的多面体匹配方法,该方法对物体的拓扑关系和结构关系进行多级匹配,利用全局优化的松驰迭代方法减少匹配误差,并由匹配的一致性准则进行匹配结果的检测,根据物体的内在特征来进行匹配,从而解决非同构物体的匹配.可广泛应用于物体识别、三维物体重建、医学图象处理等领域,实验证明此方法质量好、自动化程度高,是一种有效的全局优化结构匹配方法. 相似文献
85.
Arnold Neumaier 《Journal of Global Optimization》2003,25(2):175-181
A family of multivariate rational functions is constructed. It has strong local minimizers with prescribed function values at prescribed positions. While there might be additional local minima, such minima cannot be global. A second family of multivariate rational functions is given, having prescribed global minimizers and prescribed interpolating data. 相似文献
86.
87.
This paper introduces an analytical model to investigate the energy efficiency of the IEEE 802.11 distributed coordinated
function (DCF). This model not only accounts for the number of contending nodes, the contention window, but also the packet
size, and the channel condition. Based on this model, we identify the tradeoff in choosing optimum parameters to optimize
the energy efficiency of DCF in the error-prone environment. The effects of contention window and packet size on the energy
efficiency are examined and compared for both DCF basic scheme and DCF with four-way handshaking. The maximum energy efficiency
can be obtained by combining both the optimal packet size and optimal contention window. To validate our analysis, we have
done extensive simulations in ns-2, and simulation results seem to match well with the presented analytical results.
The Ohio Board of Regents Doctoral Enhancements Funds and the National Science Foundation under Grant CCR 0113361 have supported
this work.
Xiaodong Wang received his B.S. degree in communication engineering from Beijing Information Technical Institute of China in 1995, and
his M.S. degree in electric engineering from Beijing University of Aeronautics and Astronautics of China in 1998. He joined
China Telecom in 1998 where he worked on communication protocols for telecommunication. From June 2000 to July 2002, he worked
on GSM base station software development at Bell-labs China, Beijing, China. Currently he is a Ph.D. student in Computer Engineering
at University of Cincinnati. His research activities include wireless MAC protocols, energy saving for wireless sensor networks.
He is a student member of the IEEE.
Jun Yin received the BS degree in automatic control from Dalian Railway Institute of China in 1997, and the MS degree in flight control
from Beijing University of Aeronautics and Astronautics of China in 2001. Since 2001 she has been a Ph.D. student in the OBR
Research Center for Distributed and Mobile Computing at the University of Cincinnati. Her research interests include performance
evaluation of 802.11 MAC protocol, wireless ad hoc networks and sensor networks. She is a student member of the IEEE.
Dharma P.Agrawal IEEE Fellow, 1987; ACM Fellow, 1998; AAAS Fellow, 2003 Dr. Agrawal is the Ohio Board of Regents Distinguished Professor of
Computer Science and Computer Engineering in the department of Electrical and Computer Engineering and Computer Science, University
of Cincinnati, OH. He has been a faculty member at Wayne State University, (1977–1982) and North Carolina State University
(1982–1998). He has been a consultant to the General Dynamics Land Systems Division, Battelle, Inc., and the U. S. Army. He
has held visiting appointment at AIRMICS, Atlanta, GA, and the AT&T Advanced Communications Laboratory, Whippany, NJ. He has
published a number of papers in the areas of Parallel System Architecture, Multi computer Networks, Routing Techniques, Parallelism
Detection and Scheduling Techniques, Reliability of Real-Time Distributed Systems, Modeling of C-MOS Circuits, and Computer
Arithmetic. His recent research interest includes energy efficient routing, information retrieval, and secured communication
in ad hoc and sensor networks, effective handoff handling and multicasting in integrated wireless networks, interference analysis
in piconets and routing in scatternet, use of smart directional antennas (multibeam) for enhanced QoS, Scheduling of periodic
real-time applications and automatic load balancing in heterogeneous workstation environment. He has four approved patents
and three patent filings in the area of wireless cellular networks. 相似文献
88.
89.
The system design must be started from the concept with low cost and high performance. In this point, the topological shape of the structure is very important in the view of the structural rigidities and light-weight design.In this paper, the optimization methodology is presented in the design stage of the large optical mirror. We obtain the optimal layout through the topology optimization and then design the details through the size or shape optimization for structural rigidity. 相似文献
90.
Andrea Grosso Marco Locatelli Fabio Schoen 《Computational Optimization and Applications》2007,38(3):351-370
In this paper we perform a computational analysis of a population based approach for global optimization, Population Basin
Hopping (PBH), which was proven to be very efficient on very challenging global optimization problems by the authors (see
). The experimental analysis aims at understanding more deeply how the approach works and why it is successful on challenging
problems. 相似文献