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51.
为保证配电网动态重构后系统安全稳定的运行,提出了以网损和节点电压稳定性为目标函数的量子粒子群算法的配电网动态重构。针对配电网动态重构过程中时段划分问题,提出以负荷曲线的单调性和幅值变化大小为依据初步划分时间段落。采用整数型量子粒子群算法进行动态重构,重构过程中以相邻时段的网损变化值的关系获取最佳重构段落,然后综合考虑配电网网损最小和节点电压值最大且波动最小为目标寻找最佳重构结构。以IEEE33配电系统为例验证了所提方法的有效性和实用性。 相似文献
52.
Using short‐term resource scheduling for assessing effectiveness of CCS within electricity generation subsector 下载免费PDF全文
Colin Alie Ali Elkamel Eric Croiset Peter L. Douglas 《American Institute of Chemical Engineers》2015,61(12):4210-4234
A new methodology for assessing the effectiveness of carbon capture and storage (CCS) that does explicitly consider the detailed operation of the target electricity system is proposed. The electricity system simulation consists of three phases, each one using a modified version of an economic dispatch problem that seeks to maximize the producers’ and consumers’ surplus while satisfying the technical constraints of the system. The economic dispatch is formulated as a dynamic mixed‐integer nonlinear programming problem and implemented in general algebraic modelling system (GAMS). The generating unit with CCS is designed and simulated using Aspen Plus®. In the first case study, the operation of the IEEE RTS ’96 (Institute of Electrical and Electronics Engineers One‐Area Reliability Test System—1996) is simulated with greenhouse gas (GHG) regulation implemented in the form of CO2 permits that generators need to acquire for every unit of CO2 that it is emitted. In the second case study, CCS is added at one of the buses and the operation of the modified IEEE RTS ’96 is again simulated with and without GHG regulation. The results suggest that the detailed operation of the target electricity system should be considered in future assessments of CCS and a general procedure for undertaking this for any GHG mitigation option is proposed. Future work will use the novel methodology for assessing the effectiveness of generating units with flexible CO2 capture. © 2015 American Institute of Chemical Engineers AIChE J, 61: 4210–4234, 2015 相似文献
53.
Deciphering and handling uncertainty in shale gas supply chain design and optimization: Novel modeling framework and computationally efficient solution algorithm 下载免费PDF全文
The optimal design and operations of shale gas supply chains under uncertainty of estimated ultimate recovery (EUR) is addressed. A two‐stage stochastic mixed‐integer linear fractional programming (SMILFP) model is developed to optimize the levelized cost of energy generated from shale gas. In this model, both design and planning decisions are considered with respect to shale well drilling, shale gas production, processing, multiple end‐uses, and transportation. To reduce the model size and number of scenarios, we apply a sample average approximation method to generate scenarios based on the real‐world EUR data. In addition, a novel solution algorithm integrating the parametric approach and the L‐shaped method is proposed for solving the resulting SMILFP problem within a reasonable computational time. The proposed model and algorithm are illustrated through a case study based on the Marcellus shale play, and a deterministic model is considered for comparison. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3739–3755, 2015 相似文献
54.
在溢流管长度L0均分别设定为10mm、15mm、20mm条件下,应用Fluent软件对不同直径的直筒式水力旋流器进行了数值模拟,得到了不同入口速度下的压降和分离效率。结果表明,当溢流管直径为3mm时,旋流器的分离效率最大。旋流器主直径D一定时,使旋流器分离效率最高的直径也是一定的,一般溢流口直径选择经验值为D/(5~8.5)。 相似文献
55.
Mohammed Taleb-Berrouane Kelly Hawboldt Richard Eckert Torben Lund Skovhus 《腐蚀工程科学与技术》2018,53(5):378-392
Corrosion is one of the major causes of failure in onshore and offshore oil and gas operations. Microbiologically influenced corrosion (MIC) is inherently more complex to predict, detect and measure because, for instance, the presence of biofilm and/or bacterial products is not sufficient to indicate active microbiological corrosion. The major challenge for current MIC models is to correlate factors that influence corrosion (i.e. chemical, physical, biological and molecular variables) with the potential of having MIC. Previous work has proposed the potential for MIC as a simple product of multiple factors, without fully considering the synergy or the interference among the factors. The present work proposes a network-based approach to analyse and predict MIC potential considering the complex interactions among a total of 60 influencing factors and 20 screening parameters. The proposed model has the ability to capture the complex interdependences and the synergic interactions of the factors used to assess MIC potential and uses an object-oriented approach based on a Bayesian Network. The model has been tested and verified using real data from a pipeline leakage incident that was a result of MIC. The proposed model constitutes a significant step in deepening the understanding of when MIC occurs and its predictability.
List of acronyms: APB: acid producing bacteria; Aw: water activity; BN: Bayesian network; MIC: microbiologically influenced corrosion; MMMs: molecular microbiological methods; NRB: nitrate-reducing bacteria; OOBN: object-oriented Bayesian network; PWRI: produced water re-injection; SPs: screening parameters; SRB: sulphate-reducing bacteria; SRPs: sulphate-reducing prokaryotes; TDSs: total dissolved solids 相似文献
56.
Joint channel assignment and routing in multiradio multichannel wireless mesh networks with directional antennas 下载免费PDF全文
Nasrin Sadeghianpour Teong Chee Chuah Su Wei Tan 《International Journal of Communication Systems》2015,28(9):1521-1536
The aggregate capacity of a wireless mesh network (WMN) is severely affected by interflow interference. In this paper, we propose a network architecture that incorporates directional antennas with multiple orthogonal channels to effectively enhance the performance of WMNs. First, a sectored connectivity graph is introduced to model multiradio multichannel WMNs with directional antennas. Next we formulate the topology design, directional interface assignment, channel allocation, and routing mathematically as a mixed integer linear programming problem. This problem is solved using an iterated local search algorithm to obtain optimized network resource allocation. Simulation results indicate that the proposed architecture can achieve higher packet delivery ratio while providing better network fairness. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
57.
58.
We propose a polylithic method for medium-term scheduling of a large-scale industrial plant operating in a continuous mode. The method combines a decomposition approach, a genetic algorithm (GA) and a constructive MILP-based heuristic. In the decomposition, decisions are made at two levels, using the rolling horizon approach. At the upper level, a reduced set of products and the time period is chosen to be considered in the lower level. At the lower level, a short-term scheduling MILP-model with event-based representation is used. A heuristic solution to the lower level problem is found using a constructive Moving Window heuristic guided by a genetic algorithm. The GA is applied for finding efficient utilisation of critical units in the lower level problem. For solving the one unit scheduling problem, a parallel dynamic programming algorithm is proposed. Implementation of the dynamic programming algorithm for a graphics processing unit (GPU) is incorporated in the GA for improving its performance. The experimental study of the proposed method on a real case of a large-scale plant shows a significant improvement of the solution quality and the solving time comparing to the pure decomposition algorithm proposed in the earlier study, and confirmed suitability of the proposed approach for the real-life production scheduling. In particular, the reduction of the number of changeovers and their duration in the obtained solution as well as the CPU time of solving the problem was about 60% using the new approach. 相似文献
59.
《International Journal of Hydrogen Energy》2020,45(38):19900-19911
The Republic of Korea government has set yearly targets of hydrogen cars and buses and plans to install hydrogen refueling stations nationwide. This paper proposes a methodology for developing a strategic deployment plan with three mathematical models. For a given target, future refueling demand locations and amount from general road and expressway are systematically estimated. First, the required number of refueling stations to satisfy the target covering ratio of the total demand set by the government is determined by the Station number determination model. Next, the locations of the capacitated stations and the allocation of demand to the stations are determined by the second Max cover and the third p-median models. Since the max covering is more important than minimizing the travel time, the two models are used sequentially. The nationwide hydrogen station deployment plan for the years 2022–2040 obtained by the proposed methodology is reported. 相似文献
60.
介绍了溢流织物染色机的结构、组成部分。如何做好进缸之前、染色、后处理的准备工作,探讨了在染色过程中的操作要领,溢流染色机的具体操作实施步骤。以期对针织企业有所帮助。 相似文献