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991.
Adelmo L. Cechin José V. Canto dos Santos Carlos A. Mendel Arthur T. Gómez 《Engineering with Computers》2009,25(3):261-268
This study reports the use of a Genetic Algorithm (GA) to solve the Power System Restoration Planning Problem (PSRP). The
solution to the PSRP is described by a series of operations or a plan to be used by the Power System operator immediately
on the occurrence of a blackout in the electrical power supply. Our GA uses new initialization and crossover operators based
on the electrical power network, which are able to generate and maintain the plans feasible along GA runs. This releases the
Power Flow program, which represents the most computer demanding component, from computing the fitness function of unfeasible
individuals. The method was designed for large transmission systems and results for three different electrical power networks
are shown: IEEE 14-Bus, IEEE 30-Bus, and a large realistic system. 相似文献
992.
虚拟网映射竞争算法设计与分析 总被引:1,自引:0,他引:1
对网络虚拟化技术中的虚拟网映射问题及其研究现状进行了介绍,针对虚拟节点映射已知且物理网不支持路径分割的虚拟网映射问题,提出以物理网提供商收益最大化为目标的虚拟网映射竞争算法,并给出了算法的竞争比分析。实验表明,所提出的算法能提高物理网资源的负载均衡度和利用率,从而提高了虚拟网构建请求的接受率和物理网提供商的收益。 相似文献
993.
Scheduling plays a vital role in ensuring the effectiveness of the production control of a flexible manufacturing system (FMS). The scheduling problem in FMS is considered to be dynamic in its nature as new orders may arrive every day. The new orders need to be integrated with the existing production schedule immediately without disturbing the performance and the stability of existing schedule. Most FMS scheduling methods reported in the literature address the static FMS scheduling problems. In this paper, rescheduling methods based on genetic algorithms are described to address arrivals of new orders. This study proposes genetic algorithms for match-up rescheduling with non-reshuffle and reshuffle strategies which accommodate new orders by manipulating the available idle times on machines and by resequencing operations, respectively. The basic idea of the match-up approach is to modify only a part of the initial schedule and to develop genetic algorithms (GAs) to generate a solution within the rescheduling horizon in such a way that both the stability and performance of the shop floor are kept. The proposed non-reshuffle and reshuffle strategies have been evaluated and the results have been compared with the total-rescheduling method. 相似文献
994.
范例推理的关键步骤在于相似范例的检索,而范例库中的特征项权重起到重要的作用。文章讨论了用遗传算法来获取范例库上的特征项权重,并用两种改进的遗传算法来发现范例库上的特征项权重,给出了具体的算法,分析了实验结果。该方法可用于权重发现。 相似文献
995.
Iterative tomographic algorithms have been applied to the reconstruction of a two-dimensional object with internal defects from its projections. Nine distinct algorithms with varying numbers of projections and projection angles have been considered. Each projection of the solid object is interpreted as a path integral of the light-sensitive property of the object in the appropriate direction. The integrals are evaluated numerically and are assumed to represent exact data. Errors in reconstruction are defined as the statistics of difference between original and reconstructed objects and are used to compare one algorithm with respect to another. The algorithms used in this work can be classified broadly into three groups, namely the additive algebraic reconstruction technique (ART), the multiplicative algebraic reconstruction technique (MART) and the maximization reconstruction technique (MRT). Additive ART shows a systematic convergence with respect to the number of projections and the value of the relaxation parameter. MART algorithms produce less error at convergence compared to additive ART but converge only at small values of the relaxation parameter. The MRT algorithm shows an intermediate performance when compared to ART and MART. An increasing noise level in the projection data increases the error in the reconstructed field. The maximum and RMS errors are highest in ART and lowest in MART for given projection data. Increasing noise levels in the projection data decrease the convergence rates. For all algorithms, a 20% noise level is seen as an upper limit, beyond which the reconstructed field is barely recognizable. 相似文献
996.
介绍了一种新型立卧转换式三杆混联机床—3-TPS混联机床,对该机床的结构进行了分析。文中给出了该机床在实现立卧转换加工时的坐标变换过程及变换方程,给出了实现立卧转换加工时的后置处理算法及数学模型,并分析了该机床在两种不同加工方式下所能够实现的三轴联动加工、四轴联动加工。文中所给的算法简单、直观、实用,方程为显示。 相似文献
997.
提出了一种实时心电图ECG数据压缩算法。它是将自适应变门限算法与转折点算法相结合。自适应变门限算法是对AZTEC算法的改进.它计算ECG信号的几个统计参数来确定可变门限值。转折点算法是分析采样点的趋势并只存储每对连续的采样点中的一个。它保留信号的斜坡标志发生变化的峰点和谷点。本文算法兼有这两种算法的优点。这种算法在较高压缩比的情况下重建心电图信号失真较小. 相似文献
998.
This paper presents the development and testing of a multi objective fuzzy controller. It is dedicated to the control of thermal comfort and indoor air quality while minimising energy consumption and reducing instabilities are other constraints for this controller. After a brief introduction on the difficult task of indoor climate control, the test cell and its corresponding model is described in the second section. The model has been developed within TRNSYS. Section 3 describes the architecture of the fuzzy controller applied to these control objectives in the test cell. A hierarchical architecture has finally been selected since it is a very flexible architecture and it results in reducing the total number of fuzzy rules. The rule optimisation technique, based on genetic algorithms is also presented in the third section. Simulation results are finally presented. They prove that, after optimisation, the fuzzy controller greatly outperforms a typical ON-OFF controller on all control criteria. Energy consumption is in particular reduced by more than 10%. The fourth section of this chapter presents field experiments among 20 subjects of both ON-OFF control and fuzzy control. If major differences are not observed on the thermal comfort and indoor air quality point of view, these experiments however illustrate the importance of on-line tuning of specific fuzzy rules. 相似文献
999.
1000.
基于衰减滑动窗口数据流聚类算法研究 总被引:2,自引:0,他引:2
数据流具有数据流量大、流量连续且快速、难以存储和恢复等特性,其挖掘质量和效率是检验挖掘算法的重要标准.传统的数据流聚类挖掘算法是基于界标窗口、滑动窗口和衰减窗口模型,其算法的聚类质量较差,时间复杂度高等不足,就此类问题,研究一种滑动衰减窗口的数据流聚类算法,并对算法进行了设计与实现,有效的改善传统数据流算法聚类质量和时间效率的问题.仿真实验结果表明了该算法的有效性,达到了较满意的效果. 相似文献