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101.
准确的交通流量预测是智能交通系统中的关键问题。在分析支持向量机SVM回归估计方法参数性能的基础上,提出了粒子群算法PSO优化参数的PSO-SVM短期交通流预测模型。模型利用支持向量机具有结构风险最小化的特性和粒子群算法快速全局优化特点,实现了数据降维并且保持了交通流序列的特征,因此可以高效地预测交通流量。用G107国道现场采集的数据仿真表明了该模型的有效性,预测平均误差为3.4%。 相似文献
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103.
操作权限管理与控制是大多数计算机系统中的一个子系统,在保证整个系统正常、安全运行中起着重要的作用,该操作权限管理与控制子系统在作者使用C++Builder开发的多个应用系统中已成功使用,效果很好。 相似文献
104.
In the past few decades, restructuring has overtaken all possible domains including the electric supply industry. Restructuring has brought about considerable changes by the virtue of which electricity is now a commodity and has converted into deregulated one. Such a competitive market has paved way for innumerable participants. This has led to overloading and congestion of transmission lines. Moreover, open access transmission network has ingenerated a more intensified problem of congestion. Thus, congestion management in power systems is germane and of central importance to the power industry. In this paper a review work is carried out to unite all the publications in congestion management. 相似文献
105.
Guillermo Escrivá-Escrivá Isidoro Segura-Heras Manuel Alcázar-Ortega 《Energy and Buildings》2010,42(11):2258-2267
The significant and continuous increment in the global electricity consumption is asking for energy saving strategies. Efficient control for heating, ventilation and air-conditioning systems (HVAC) is the most cost-effective way to minimize the use of energy in buildings. In this framework, an energy management and control system (EMCS) has been developed to schedule electricity end-uses in the campus of the Universidad Politécnica de Valencia (UPV), Spain. This paper presents an evaluation performed by using the EMCS of different control strategies for HVAC split systems. It analyzed the effect of different schedules for a common air-conditioning device and demand response strategies are tested in several situations. The economic saving is calculated taking into account the electricity contract clauses. Finally, a test is made for the control of a group of similar devices in order to reduce the maximum peak power in consumption and to obtain a flexible load shape with the HVAC loads. The studies are then extrapolated to a larger system, the whole University campus, for which energy and economic savings are quantified. 相似文献
106.
A bi-level school bus routing problem with bus stops selection and possibility of demand outsourcing
This paper develops a bi-level mathematical model for the school bus routing problem aiming at designing an efficient transportation system considering the possibility of predicting the students’ response. In the real world, the demand for using private cars depends on how well public transportation systems are operating especially in metropolitan cities. An inefficient public transportation will lead to an increase in the demand for using private cars. This issue will result in problems such as increased traffics and urban pollutions. To address this issue, an efficient public transportation system is designed by developing a new bi-level mathematical model. In the proposed model, the designer of the public transportation system, as the upper-level decision-maker, will locate appropriate bus stops and identify bus navigation routes. Subsequently, the decision regarding the allocation of students to transportation systems or outsourcing them will be made at the lower level which is considered as an operational-level decision-making. To solve this problem, two hybrid metaheuristic approaches named GA-EX-TS and SA-EX-TS have been proposed based on location-allocation-routing (LAR) strategy. The performance of these proposed methods is compared with exact solutions achieved from an explicit enumeration approach followed in the small-scale instances. Finally, the proposed approaches are used to solve 50 random instance problems. Comparing the results of the two tuned hybrid algorithms and conducting the sensitivity analysis of the model provide evidence for the good performance of the proposed approach. 相似文献
107.
文章对人们消费需求的变化进行分析,并提出杂粮分量式包装的必要性,结合实例,阐述分量式包装的便利性、品牌化、安全性的设计方法,以期通过分量式的包装设计满足消费者对杂粮小分量的食用需求,给消费者带来便利,从而适应竞争日益激烈的市场环境。 相似文献
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109.
随着能源互联网的出现和智能电网的发展,使得电能供给与电能需求能够更紧密的联系,也促进了电力交易市场条件下需求响应的信息化和智能化,用户根据自身情况在需求响应市场上进行出价与竞争,也更好的反映了电能的市场价值。本文结合智能电网下的需求响应市场,描述了多用户对电能竞争的一般场景与模型,从理论和算法上分析用户出价与市场调节的最优化问题,在给定的一般情况下,证明了存在一个纳什均衡,使得市场竞价能得到一个最终解的集合,实现用户竞争后的稳定解,同时给出了优化问题解的一个高效算法。 相似文献
110.
介绍了ST型煤矿用阻燃钢丝绳芯输送带的型号规格、性能要求、结构特点、阻燃机理、使用要求及发展趋势,为使用单位相关人员更好地使用与维护提供帮助。 相似文献