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61.
Spanning tree-based genetic algorithm for bicriteria transportation problem   总被引:2,自引:0,他引:2  
In this paper, we present a new approach which is spanning tree-based genetic algorithm for bicriteria transportation problem. The transportation problem have the special data structure in solution characterized as a spanning tree. In encoding transportation problem, we introduce one of node encoding which is adopted as it is capable of equally and uniquely representing all possible basic solutions. The crossover and mutation was designed based on this encoding. And we designed the criterion that chromosome always feasibility converted to a transportation tree. In the evolutionary process, the mixed strategy and roulette wheel selection is used. Numerical experiments will be shown the effectiveness and efficiency of the proposed algorithm.  相似文献   
62.
Neural Network(NN) is well-known as one of powerful computing tools to solve optimization problems. Due to the massive computing unit-neurons and parallel mechanism of neural network approach we can solve the large-scale problem efficiently and optimal solution can be gotten. In this paper, we intoroduce improvement of the two-phase approach for solving fuzzy multiobjectve linear programming problem with both fuzzy objectives and constraints and we propose a new neural network technique for solving fuzzy multiobjective linear programming problems. The procedure and efficiency of this approach are shown with numerical simulations.  相似文献   
63.
In this paper, we examine the classification performance of fuzzy if-then rules selected by a GA-based multi-objective rule selection method. This rule selection method can be applied to high-dimensional pattern classification problems with many continuous attributes by restricting the number of antecedent conditions of each candidate fuzzy if-then rule. As candidate rules, we only use fuzzy if-then rules with a small number of antecedent conditions. Thus it is easy for human users to understand each rule selected by our method. Our rule selection method has two objectives: to minimize the number of selected fuzzy if-then rules and to maximize the number of correctly classified patterns. In our multi-objective fuzzy rule selection problem, there exist several solutions (i.e., several rule sets) called “non-dominated solutions” because two conflicting objectives are considered. In this paper, we examine the performance of our GA-based rule selection method by computer simulations on a real-world pattern classification problem with many continuous attributes. First we examine the classification performance of our method for training patterns by computer simulations. Next we examine the generalization ability for test patterns. We show that a fuzzy rule-based classification system with an appropriate number of rules has high generalization ability.  相似文献   
64.
孟耕  张浩 《电测与仪表》2006,43(9):43-45,28
以0.02级三相宽量程多功能标准电能表定型产品为例,介绍了提高整机工作稳定性和温度特性等重要技术指标的技术方法。  相似文献   
65.
针对侯马晋田热电厂1号机组在调试启动中出现的凝汽器热井突发性无水现象进行了详细分析,指出了解决该问题的措施,为该类型的凝汽器运行提供必要的参考。  相似文献   
66.
DS-CDMA的抗干扰性能分析及在卫星通信中的运用   总被引:2,自引:0,他引:2  
DS—CDMA的频谱和功率利用率极高,具有抗干扰能力强、保密性能好、辐射能量少等优点, 特别适合于卫星通信。本文叙述了数字DS—CDMA的基本原理,并对其抗干扰性能作了一定分析,同时介绍 了DS—CDMA在卫星通信中运用的情况。  相似文献   
67.
Although conventional electron microscopy (EM) requires samples to be in vacuum, most chemical and physical reactions occur in liquid or gas. The Atmospheric Scanning Electron Microscope (ASEM) can observe dynamic phenomena in liquid or gas under atmospheric pressure in real time. An electron-permeable window made of pressure-resistant 100 nm-thick silicon nitride (SiN) film, set into the bottom of the open ASEM sample dish, allows an electron beam to be projected from underneath the sample. A detector positioned below captures backscattered electrons. Using the ASEM, we observed the radiation-induced self-organization process of particles, as well as phenomena accompanying volume change, including evaporation-induced crystallization. Using the electrochemical ASEM dish, we observed tree-like electrochemical depositions on the cathode. In silver nitrate solution, we observed silver depositions near the cathode forming incidental internal voids. The heated ASEM dish allowed observation of patterns of contrast in melting and solidifying solder. Finally, to demonstrate its applicability for monitoring and control of industrial processes, silver paste and solder paste were examined at high throughput. High resolution, imaging speed, flexibility, adaptability, and ease of use facilitate the observation of previously difficult-to-image phenomena, and make the ASEM applicable to various fields.  相似文献   
68.
基于RADIUS的校园网认证管理系统的研究与实现   总被引:1,自引:1,他引:1  
介绍了RADIUS协议的结构,讨论了其认证的工作过程。以校园网实际应用为例,建立了RADIUS认证计费服务器的网络架构和功能模型。根据PPPoE接入认证计费的特点,对开发中的数据库关键问题进行了详细分析,解决了校团网拨号认证和计费的问题。  相似文献   
69.
利用Spraywatch热喷涂监控仪对等离子射流的形貌进行了观察,对飞行粒子的速度、温度进行了测量,并把等离子喷涂射流的产生、脉动和射流对粒子的作用进行了分析研究.结果表明:射流脉动主要是由于电孤大尺寸分流和卷吸作用造成的,改善射流脉动可以减小射流中粒子的速度和温度梯度,进而可以提高等离子喷涂的质量.  相似文献   
70.
The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary.  相似文献   
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