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981.
An improved adaptive genetic algorithm (IAGA) for solving the minimum makespan problem of job-shop scheduling problem (JSP) is presented. Though the traditional genetic algorithm (GA) exhibits implicit parallelism and can retain useful redundant information about what is learned from previous searches by its representation in individuals in the population, yet GA may lose solutions and substructures due to the disruptive effects of genetic operators and is not easy to regulate GA’s convergence. The proposed IAGA is inspired from hormone modulation mechanism, and then the adaptive crossover probability and adaptive mutation probability are designed. The proposed IAGA is characterized by simplifying operations, high search precision, overcoming premature phenomenon and slow evolution. The proposed method by employing operation-based encoding is effectively applied to solve a dynamic job-shop scheduling problem (DJSP) and a complicated contrastive experiment of JSP in manufacturing system. Meanwhile, in order to ensure to create a feasible solution, a new method for crossover operation is adopted, named, partheno-genetic operation (PGO). The computational results validate the effectiveness of the proposed IAGA, which can not only find optimal or close-to-optimal solutions but can also obtain both better and more robust results than the existing genetic algorithms reported recently in the literature. By employing IAGA, machines can be used more efficiently, which means that tasks can be allocated appropriately, production efficiency can be improved, and the production cycle can be shortened efficiently. 相似文献
982.
提出一种利用图像序列的平稳性和相关性检验的天气场景分类方法.首先,给出天气场景的定义和分类标准;其次,该方法通过分段逆序平稳性检验,提出图像均值子序列逆序总数数学期望和方差的计算方法,将天气场景分为平稳性天气场景和非平稳性天气场景;最后,提出自相关函数的分类检验方法,建立对待分类场景图像序列的激变描述,完成对其所属静态... 相似文献
983.
用于设备级控制系统与分散式I/O通信的Profibus-DP是市场占有率绝对领先的总线技术.设计了一种基于西门子的SPC3的Profibus-DP的数据显示智能从站,详细分析了从站的硬件及软件结构,研究并解决了RS485通信现场设备与Profibus-DP现场总线通信问题.测试实验采用基于PC加软PLC构成Profibus-DP 1类主站,数据显示单元做从站,通过在PC机上监控Profibus通信报文的方法,成功验证了此显示单元模块能和西门子的设备进行互连,符合Profibus-DP标准. 相似文献
984.
讨论采用J2ME技术实现移动远程控制应用的方法.方法在手机端采用MIDP里的HttpConnection接口技术,PC端采用Servlet技术,并实现了手机对PC机的远程控制.方法可运用于智能居家、家电信息化等,推动物联网发展普及. 相似文献
985.
This paper considers an economic lot sizing model with constant capacity, non-increasing setup cost, and convex inventory cost function. Algorithms with computational time of O(N×TDN)have been developed for solving the model, where N is the number of planning periods and TDN is the total demand. This study partially characterizes the optimal planning structure of the model. A new efficient algorithm with computational time of O(N log N) has also been developed based on the partial optimal structure. Moreover, computational study demonstrates that the new algorithm is efficient. 相似文献
986.
Junwei Zhang Bu-Sung Lee Xueyan Tang Chai-Kiat Yeo 《The Journal of supercomputing》2011,56(3):245-269
Data Grid has evolved to be the solution for data-intensive applications, such as High Energy Physics (HEP), astrophysics,
and computational genomics. These applications usually have large input of data to be analyzed and these input data are widely
replicated across Data Grid to improve the performance. The job scheduling performance on traditional computing jobs can be
studied using queuing theory. However, with the addition of data transfer, the job scheduling performance is too complex to
be modeled. In this research, we study the impact of data transfer on the performance of job scheduling in the Data Grid environment.
We have proposed a parallel downloading system that supports replicating data fragments and parallel downloading of replicated
data fragments, to improve the job scheduling performance. The performance of the parallel downloading system is compared
with non-parallel downloading system, using three scheduling heuristics: Shortest Turnaround Time (STT), Least Relative Load
(LRL) and Data Present (DP). Our simulation results show that the proposed parallel download approach greatly improves the
Data Grid performance for all three scheduling algorithms, in terms of the geometric mean of job turnaround time. The advantage
of parallel downloading system is most evident when the Data Grid has relatively low network bandwidth and relatively high
computing power. 相似文献
987.
This paper investigates the delay-probability-distribution-dependent stability problem of stochastic genetic regulatory networks (GRNs) with random discrete time delays and distributed time delays which exist in both translation process and feedback regulation process. The information of the probability distribution of the discrete time delays is considered and transformed into parameter matrices of the GRN models. By introducing a new Lyapunov functional which takes into account the ranges of delays and employing some free-weighting matrices, some new delay-probability-distribution-dependent stability criteria are established in the form of linear matrix inequalities (LMIs) to guarantee the GRNs to be asymptotically stable in the mean square. In addition, when estimating the upper bounds of the derivative of Lyapunov functionals, we carefully handle the additional useful terms about the distributed delays, which may lead to the less conservative results. The new criteria are applicable to both slow and fast time delays. Finally, numerical examples are given to illustrate the effectiveness of our theoretical results and less conservativeness of the proposed method. 相似文献
988.
989.
Ramsey理论是组合数学中一个庞大而又丰富的领域,在集合论、逻辑学、分析以及代数学上具有极重要的应用.Ramsey数的求解是非常困难的,迄今为止只求出9个Ramsey数的准确值.探讨了DNA生物分子超级计算在求解这一困难数学问题的可能性.将Adleman-Lipton模型生物操作与粘贴模型解空间相结合的DNA计算模型... 相似文献
990.
Combined with motion capture and dynamic simulation, characters in animation have realistic motion details and can respond to unexpected contact forces. This paper proposes a novel and real-time character motion generation approach which introduces a parallel process, and uses an approximate nearest neighbor optimization search method. Besides, we employ a support vector machine (SVM), which is trained on a set of samples and predicts a subset of our ‘return-to’ motion capture (mocap) database in order to reduce the search time. In the dynamic simulation process, we focus on designing a biomechanics based controller which detects the balance of the characters in locomotion and drives them to take several active and protective responses when they fall to the ground in order to reduce the injuries to their bodies. Finally, we show the time costs in synthesis and the visual results of our approach. The experimental results indicate that our motion generation approach is suitable for interactive games or other real-time applications. 相似文献