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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
在工业软件的用户生产现场测试中,可能由于操作风险、用户生产限制等约束而导致测试不充分,针对实践中的难点提出新的现场测试过程及其测试数据生成方法。定义了测试拆分子集及相关属性概念,根据现场因素设计的测试拆分子集提高了现场测试可主动性;综合现场因素设计拆分方案,采用针对性的辅助管理程序引导每个测试拆分子集的现场测试的实施;通过对生产现场的历史数据的处理建立针对各测试拆分子集的测试准备数据库,以搜索测试准备数据库的结果为依据并结合现场因素设计现场主动测试的输入数据,并说明了实践中的综合实施过程。通过石化生产优化控制系统的现场测试的实际案例,说明了这种方法能够在预防风险的前提下显著提高现场测试的充分性和测试效率。 相似文献
982.
汤辉 《计算机工程与科学》2016,38(6):1149-1155
在非协作通信和军事通信对抗中,接收机需要对接收到的多个通信信号进行分离,以提取出有用的信号,这可以归为通信信号卷积盲分离问题。首先构建信号模型,并将问题转化为多个矩阵的联合分块对角化。然后提出一种新的非正交矩阵联合分块对角化算法,使用最速下降法得到迭代算法,并分析了算法的可能优化策略和计算复杂度。最后仿真实验验证了新算法的有效性和可靠性,在无须计算最优步长等条件下能够获得比现有算法更快的收敛速度。 相似文献
983.
Chengqiang Huang Qi Zhang Hui Wang Songlin Feng 《Journal of the Society for Information Display》2016,24(12):713-720
A selective current limit algorithm based on color space conversion is proposed in this paper. There are mainly two advantages for this algorithm. Firstly, only the luminance component Y is decreased, and the color component Cb or Cr is not changed; thus, the color distortion is avoided in the process of current limit. Secondly, the current of pixels with high luminance is limited while that of those pixels with low luminance is not, which means current limit is executed selectively. For the same value of mean square error, the simulation results show that the ratio of pixels with high luminance of the image processed by the proposed algorithm is zero, and that processed by the net power control and the algorithm based on color space conversion is 0.081 and 0.0854, respectively. This algorithm is implemented on a field‐programmable gate array to drive the image display on the AMOLED panel. 相似文献
984.
985.
The design and test of dual/triple‐mode bandpass filter based on temporal coupled‐mode theory 下载免费PDF全文
Hui Xu Jiong‐Jiong Mo Xiu‐Qin Xu Xu Ding Zhi‐Yu Wang Yong‐Heng Shang Li‐Ping Wang Fa‐Xin Yu 《国际射频与微波计算机辅助工程杂志》2016,26(7):609-622
In this article, the design and test of both a K‐band dual‐mode bandpass filter (BPF) pair and a K‐band triple‐mode BPF are presented based on N‐mode temporal coupled‐mode theory (CMT). The expressions of transmission and reflection responses are analytically derived. All the parameters in the expressions have clear physical meanings and are easily optimized to reach the required filter performance. Aided by eigenmode simulations, concrete structures of the three integrated BPFs are designed and optimized to approach the calculated physical parameters. After the fabrications and measurements of the three BPFs, extended upper/lower stopband with high stopband rejections are achieved, and by increasing the number of resonant modes, improved frequency selectivity and better passband flatness are obtained. The analytical analysis well predicts the simulation and measurement results, which provides an efficient way for BPF designs. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:609–622, 2016. 相似文献
986.
987.
Yuanyuan Liu Jing Liu Ke Wang Hui Zhang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(11):4363-4376
The classical operational law of uncertain variables proposed by Liu makes an important contribution to the development of the uncertainty theory in both theories and applications. It provides a powerful and practical approach for calculating the uncertainty distribution of strictly monotone function of uncertain variables. However, the restriction on strictly monotone functions of the operational law limits its applications since many practical problems cannot be modeled by strictly monotone functions but general monotone functions. Therefore, an extension of the original operational law is needed. For this purpose, some properties concerning the uncertainty distributions of monotone functions of uncertain variables as well as the generalized inverse uncertainty distributions are presented first in this paper. On the basis of these discussions, a generalized operational law is proposed as a natural extension of the original operational law. Then the uncertainty distribution of a general monotone function of independent regular uncertain variables can be derived, which is analogous to the way that suggested by the original operational law for dealing with strictly monotone functions. Furthermore, as an application of the generalized operational law, a theorem for calculating the expected values of general monotone functions of uncertain variables is presented as well. 相似文献
988.
Alexandre Sawczuk da Silva Hui Ma Mengjie Zhang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(10):3851-3867
Web services, which can be described as functionality modules invoked over a network as part of a larger application are often used in software development. Instead of occasionally incorporating some of these services in an application, they can be thought of as fundamental building blocks that are combined in a process known as Web service composition. Manually creating compositions from a large number of candidate services is very time consuming, and developing techniques for achieving this objective in an automated manner becomes an active research field. One promising group of techniques encompasses evolutionary computing, which can effectively tackle the large search spaces characteristic of the composition problem. Therefore, this paper proposes the use of genetic programming for Web service composition, investigating three variations to ensure the creation of functionally correct solutions that are also optimised according to their quality of service. A variety of comparisons are carried out between these variations and two particle swarm optimisation approaches, with results showing that there is likely a trade-off between execution time and the quality of solutions when employing genetic programming and particle swarm optimisation. Even though genetic programming has a higher execution time for most datasets, the results indicate that it scales better than particle swarm optimisation. 相似文献
989.
Xinyu Zhou Zhijian Wu Hui Wang Shahryar Rahnamayan 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2016,20(3):907-924
As a relatively new global optimization technique, artificial bee colony (ABC) algorithm becomes popular in recent years for its simplicity and effectiveness. However, there is still an inefficiency in ABC regarding its solution search equation, which is good at exploration but poor at exploitation. To overcome this drawback, a Gaussian bare-bones ABC is proposed, where a new search equation is designed based on utilizing the global best solution. Furthermore, we employ the generalized opposition-based learning strategy to generate new food sources for scout bees, which is beneficial to discover more useful information for guiding search. A comprehensive set of experiments is conducted on 23 benchmark functions and a real-world optimization problem to verify the effectiveness of the proposed approach. Some well-known ABC variants and state-of-the-art evolutionary algorithms are used for comparison. The experimental results show that the proposed approach offers higher solution quality and faster convergence speed. 相似文献
990.
Internet Data Center (IDC) is one of important emerging cyber-physical systems. To guarantee the quality of service for their worldwide users, large Internet service providers usually operate multiple geographically distributed IDCs. The enormous power consumption of these data centers may lead to both huge electricity bills and considerable carbon emissions. To mitigate these problems, on-site renewable energy plants are emerging in recent years. Since the renewable energy is intermittent, greening geographical load balancing (GGLB for short) has been proposed to reduce both the electricity bills and carbon emissions by following the renewables. However, GGLB is not able to well deal with the wildly fluctuating wind power when applied into IDCs with on-site wind energy plants. It may either fail to minimize the total electricity bills or incur the costly frequent on–off switching of servers. In order to minimize the total electricity bills of geographically distributed IDCs with on-site wind energy plants, we formulate the total electricity bills minimization problem and propose a novel two-time-scale load balancing framework TLB to solve it. First, TLB models the runtime cooling efficiency for each IDC. Then it predicts the future fine-grained (e.g., 10-min) on-site wind power output at the beginning of each scheduling period (e.g., an hour). After that, TLB transforms the primal optimization problem into a typical mixed-integer linear programming problem and solves it to finally obtain the optimal scheduling policy including the open server number as well as the request routing policy. It is worth noting that the open server number of each IDC will remain the same during each scheduling period. As an application instance of TLB, we also design a two-time-scale load balancing algorithm TLB-ARMA for our experimental scenario. Evaluation results based on real-life traces show that TLB-ARMA is able to reduce the total electricity bills by as much as 12.58 % compared with the hourly executed GGLB without incurring the costly repeated on–off switching of servers. 相似文献