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排序方式: 共有245条查询结果,搜索用时 31 毫秒
1.
Transmission system restoration with co-optimization of repairs,load pickups,and generation dispatch
This paper studies the restoration of a transmission system after a significant disruption such as a natural disaster. It considers the co-optimization of repairs, load pickups, and generation dispatch to produce a sequencing of the repairs that minimizes the size of the blackout over time. The core of this process is a Restoration Ordering Problem (ROP), a non-convex mixed-integer nonlinear program that is outside the capabilities of existing solver technologies. To address this computational barrier, the paper examines two approximations of the power flow equations: The DC model and the recently proposed LPAC model. Systematic, large-scale testing indicates that the DC model is not sufficiently accurate for solving the ROP. In contrast, the LPAC power flow model, which captures line losses, reactive power, and voltage magnitudes, is sufficiently accurate to obtain restoration plans that can be converted into AC-feasible power flows. An experimental study also suggests that the LPAC model provides a robust and appealing tradeoff between accuracy and computational performance for solving the ROP. 相似文献
2.
The Vehicle Routing Problem with Simultaneous Pickup and Delivery (VRPSPD) is an extension to the classical Vehicle Routing Problem (VRP), where customers may both receive and send goods simultaneously. The Vehicle Routing Problem with Mixed Pickup and Delivery (VRPMPD) differs from the VRPSPD in that the customers may have either pickup or delivery demand. However, the solution approaches proposed for the VRPSPD can be directly applied to the VRPMPD. In this study, an adaptive local search solution approach is developed for both the VRPSPD and the VRPMPD, which hybridizes a Simulated Annealing inspired algorithm with Variable Neighborhood Descent. The algorithm uses an adaptive threshold function that makes the algorithm self-tuning. The proposed approach is tested on well-known VRPSPD and VRPMPD benchmark instances derived from the literature. The computational results indicate that the proposed algorithm is effective in solving the problems in reasonable computation time. 相似文献
3.
The present work is devoted to measure the absolute magnetic field produced by different coils in the EGYPTOR tokamak using a calibrated pickup coil. Scaling these measurements in different equations connected with the discharge currents from each supply system are performed. The pickup coil used in the present study is well calibrated with Helmholz coils at the IPP in Prague, Czech Republic. A 0.2% deviation has been found between an evaluation done in the present study and the calibration using Helmholz coils. Experimental measurements of the toroidal magnetic field are in good agreement with calculations to within 2%. Very low values of stray magnetic field components arising from TF and OH coils are recorded which proves that the compensation coils for these components are sufficient. 相似文献
4.
通过混合集成型结构光学拾音器的光学设计和芯片设计,制作了包含微光学棱镜,光电探测器和信号放大电路的混合集成型光学拾音器。经过测试,发现有较好的信号输出特性,表明混合集成型光学拾音器已基本研制成功。 相似文献
5.
电除尘器绝缘子的设计与选择 总被引:1,自引:0,他引:1
根据电除尘器绝缘子的功能、工况条件等特点,分别从材质、外形尺寸等方面介绍了设计和选择的注意事项。为用户合理地选择电除尘器绝缘子提供了帮助。 相似文献
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The study concerns the location-routing problem with simultaneous pickup and delivery (LRPSPD) in which the pickup and delivery take place at the same time for each customer. The goal is to determine the facility locations and vehicle routes in order to minimise the total system cost as a sum of facility opening cost, vehicle fixed cost and vehicle travel cost. A simulated annealing (SA) heuristic is proposed for the problem and extensive computational experiments are conducted. The results show that the proposed SA effectively solves LRPSPD and outperforms existing exact approaches in terms of solution quality. 相似文献
9.
The static bike rebalancing problem (SBRP) concerns the task of repositioning bikes among stations in self-service bike-sharing systems. This problem can be seen as a variant of the one-commodity pickup and delivery vehicle routing problem, where multiple visits are allowed to be performed at each station, i.e., the demand of a station is allowed to be split. Moreover, a vehicle may temporarily drop its load at a station, leaving it in excess or, alternatively, collect more bikes from a station (even all of them), thus leaving it in default. Both cases require further visits in order to meet the actual demands of such station. This paper deals with a particular case of the SBRP, in which only a single vehicle is available and the objective is to find a least-cost route that meets the demand of all stations and does not violate the minimum (zero) and maximum (vehicle capacity) load limits along the tour. Therefore, the number of bikes to be collected or delivered at each station must be appropriately determined in order to respect such constraints. We propose an iterated local search (ILS) based heuristic to solve the problem. The ILS algorithm was tested on 980 benchmark instances from the literature and the results obtained are competitive when compared to other existing methods. Moreover, our heuristic was capable of finding most of the known optimal solutions and also of improving the results on a number of open instances. 相似文献
10.
为了满足汽车产业低能耗、轻量化、高安全性的发展趋势,高强钢已在当前汽车技术中得到广泛应用。对采用B410LA/JSC590R低合金高强钢制造的皮卡B柱内板上段加强板进行了工艺分析,设计了两种成形方案:方案1,零件的曲面法兰设计在压料面上;方案2,零件的曲面法兰设计在拉延造型的凸模上。通过AutoForm软件对该两种成形工艺方案进行数值模拟分析,成功预测了两种方案的板料成形过程中可能存在的起皱、开裂和成形不足等缺陷,并进行综合比较得到,方案2优于方案1,且模拟结果经过生产验证,生产出的零件质量良好。 相似文献