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991.
Sufficient conditions of technical stability in measure are established for nonstationary automatic-control systems with variable structure and logic control laws dependent on the mismatch error and its derivatives of finite order for all admissible initial perturbations from a predefined measurable set of initial perturbations. The associated systems of differential equations contain time-dependent coefficients. The logic control laws are described by a variable jump control function of the mismatch coordinate and its derivatives of finite order that is no higher than that of the initial system of equations. Using a signal and its derivatives for control increases the quality of discontinuous control. The relationship between the eigenvalues of the quadratic forms of the corresponding Liapunov functions and the criteria of technical stability is revealed. The general results are applied to a variable-structure system of the third order  相似文献   
992.
In this paper we present two new heuristic approaches to solve the Discrete Ordered Median Problem (DOMP). Described heuristic methods, named HGA1 and HGA2 are based on a hybrid of genetic algorithms (GA) and a generalization of the well-known Fast Interchange heuristic (GFI). In order to investigate the effect of encoding on GA performance, two different encoding schemes are implemented: binary encoding in HGA1, and integer representation in HGA2. If binary encoding is used (HGA1), new genetic operators that keep the feasibility of individuals are proposed. Integer representation keeps the individuals feasible by default, so HGA2 uses slightly modified standard genetic operators. In both methods, caching GA technique was integrated with the GFI heuristic to improve computational performance. The algorithms are tested on standard ORLIB p-median instances with up to 900 nodes. The obtained results are also compared with the results of existing methods for solving DOMP in order to assess their merits.  相似文献   
993.
A waste pipeline, considered as an undesirable facility, is to be located in a coastal region. Two criteria are taken into account, the Euclidean distance from a given set of protected areas (coral reefs and sandbanks) and a utility function related to the pipe length, both to be maximized. The paper describes a methodology to obtain an efficient set of points where the extreme of a marine pipeline should be located. Since the formulation of the model is based on the zone Voronoi diagram, the computational complexity of the solving procedure is low.  相似文献   
994.
基于电流环的高楼供水水位远程自动监测系统的研制   总被引:1,自引:0,他引:1  
介绍一种采用20mA电流环驱动方式的高楼供水水位远程自动监测系统,此系统能进行远距离、高速度通信,并且有较强的现场抗干扰和噪声抑制能力,通过无线数据传输的方式向中心发送水位信息,实现了水位监测的实时性.  相似文献   
995.
程慧杰  乔付 《信息技术》2006,30(9):64-66
论述了采用GSM无线通信方式,对远程自动抄表系统(简称ARMS)的方案、系统的组成、硬件的配置、软件设计、工作原理、功能以及技术性能进行了介绍。该系统通过下位机(简称MCU)和无线收发模块(简称PTR2000)采集、整理数据,通过串口(简称RS232)和无线MODEM模块与上位机(简称PC机)通信,电力公司通过上位机收集数据,实现远程无线自动抄表的功能。  相似文献   
996.
This paper addresses the finite size 1-center placement problem on a rectangular plane in the presence of barriers. Barriers are regions in which both facility location and travel through are prohibited. The feasible region for facility placement is subdivided into cells along the lines of Larson and Sadiq [R.C. Larson, G. Sadiq, Facility locations with the Manhattan metric in the presence of barriers to travel, Operations Research 31 (4) (1983) 652–669]. To overcome complications induced by the center (minimax) objective, we analyze the resultant cells based on the cell corners. We study the problem when the facility orientation is known a priori. We obtain domination results when the facility is fully contained inside 1, 2 and 3-cornered cells. For full containment in a 4-cornered cell, we formulate the problem as a linear program. However, when the facility intersects gridlines, analytical representation of the distance functions becomes challenging. We study the difficulties of this case and formulate our problem as a linear or nonlinear program, depending on whether the feasible region is convex or nonconvex. An analysis of the solution complexity is presented along with an illustrative numerical example.  相似文献   
997.
The Colombian coffee supply network, managed by the Federación Nacional de Cafeteros de Colombia (Colombian National Coffee-Growers Federation), requires slimming down operational costs while continuing to provide a high level of service in terms of coverage to its affiliated coffee growers. We model this problem as a biobjective (cost-coverage) uncapacitated facility location problem (BOUFLP). We designed and implemented three different algorithms for the BOUFLP that are able to obtain a good approximation of the Pareto frontier. We designed an algorithm based on the Nondominated Sorting Genetic Algorithm; an algorithm based on the Pareto Archive Evolution Strategy; and an algorithm based on mathematical programming. We developed a random problem generator for testing and comparison using as reference the Colombian coffee supply network with 29 depots and 47 purchasing centers. We compared the algorithms based on the quality of the approximation to the Pareto frontier using a nondominated space metric inspired on Zitzler and Thiele's. We used the mathematical programming-based algorithm to identify unique tradeoff opportunities for the reconfiguration of the Colombian coffee supply network. Finally, we illustrate an extension of the mathematical programming-based algorithm to perform scenario analysis for a set of uncapacitated location problems found in the literature.  相似文献   
998.
本文提出一种基于小波压缩域的图像/视频字符自动检测定位方法.对于基于小波变换的压缩格式图像/视频,仅部分解压即可实现具有复杂背景的字符区域定位.与其他定位方法相比,明显降低计算复杂度,对字符尺寸的鲁棒性,检测精度显著提高.初步实验结果验证了该方法的有效性和快速性.  相似文献   
999.
文章提出了一种基于简化的多算法协同定位方法,实现Chan算法、Tayor算法和Sx算法等多种定位算法的融合。最后仿真结果表明,多算法协同定位模型能得到更准确可靠的移动台估计位置,有效提高了定位精度。  相似文献   
1000.
用电击法将带有CAO基因片段的Psp109-E8质粒转入到莱茵衣藻cbnl-48mt^+基因突变株中后.转化子中出现了叶绿素b的恢复性表达,初步验证了丧失合成叶绿素b能力的cbn1和cao突变基因具有等位性的属性;将1641-1b(cbn1-43mt^+)和CC-1354(cbn1-48mt^+)突变株分别与CBS5(cao5mt^-)突变株的分离子CBS5-c1和CBS5-c5进行杂交.并通过随机分析方法分离获得1842个减数分裂后代分离子.经检测其中均没有发现有野生性表型的分离子.初步证明cbn1和cao4突变基因问有着非常紧密的连锁性;从上述杂交系分离获得的50多个四分子中也没有检测发现显示野生性表型的分离子.进一步证明了cbn1和cao突变基因具有等位性的属性;根据CAO基因的DNA序列,从5'-端和3’-端设计两个探针,分别与莱茵衣藻核基因组I号染色体上GBP1和RB47分子标记之间的21个BAC克隆进行的点杂交实验结果显示.该两个探针序列与21号BAC克隆(莱茵衣藻BAC文库序列号33e2)片段均有同源区的特性,此项DNA杂交实验初步证明.CAO基因的位点是在cbml突 变基因左右两侧的GBP1和RB47两个分子标记之间的33e2 BAC克隆片段区.  相似文献   
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