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A RECOGNITION PROBLEM IN CONVERTING LINEAR PROGRAMMING TO NETWORK FLOW MODELS 被引量:1
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作者 林诒勋 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第1期76-85,共10页
The main goal of this paper is to study the following combinatorial problem : given a finite set E = (e1, e2, ...,em} and a subset family a - [S1,S2, ... ,Sk} of E , does there exist a tree T with the edge set E such ... The main goal of this paper is to study the following combinatorial problem : given a finite set E = (e1, e2, ...,em} and a subset family a - [S1,S2, ... ,Sk} of E , does there exist a tree T with the edge set E such that each induced subgraph T[Si] of Si is precisely a path (1≤i≤k) ? 展开更多
关键词 Linear programming Network flow Polygon-matrix SEQUENCING Tree.
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基于Return-Oriented Programming的程序攻击与防护 被引量:6
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作者 黄志军 郑滔 《计算机科学》 CSCD 北大核心 2012年第B06期1-5,23,共6页
随着W⊕X等技术的引入,传统的代码注入攻击几乎被消除,return-to-lib攻击受到很大程度的抑制。在此背景下,Hovav Shacham提出了Return-Oriented Programming(ROP)的思想,该思想基于栈溢出的原理,通过使用程序库中有效的以ret指令结尾的... 随着W⊕X等技术的引入,传统的代码注入攻击几乎被消除,return-to-lib攻击受到很大程度的抑制。在此背景下,Hovav Shacham提出了Return-Oriented Programming(ROP)的思想,该思想基于栈溢出的原理,通过使用程序库中有效的以ret指令结尾的短指令序列构建gadget集合,使之具有图灵完备特性,来完成计算和攻击。讲述ROP思想自提出以来的一些研究成果和其实际的攻击能力,阐述ROP自动化的当前成果与未来可能的发展方向,进而分析和预测ROP自动化的下一步的研究方向。同时,也将从ROP的几个特征分析消除这种攻击的策略和方法,并介绍目前已有的防护思想和成果,论述这些方法的优缺点和改进方向。综合阐述ROP攻击与ROP防护这一矛与盾的问题,力争使读者理解ROP的思想,知悉当前的发展状态,并在此基础上能够进一步推进ROP攻击及其防范的研究。 展开更多
关键词 ROP 程序自动化 地址随机化 栈溢出 程序控制流 程序安全
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不确定条件下的零等待Flow shop生产调度问题 被引量:3
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作者 郑璐 顾幸生 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第2期188-193,198,共7页
研究了处理时间不确定条件下,含零等待模块的模糊Flowshop生产调度问题;采用三角模糊数描述处理时间的不确定性,用零等待策略对加工过程进行约束,建立了基于模糊规划理论的零等待Flowshop调度模型,通过中间值最大隶属度的方法,将原有的... 研究了处理时间不确定条件下,含零等待模块的模糊Flowshop生产调度问题;采用三角模糊数描述处理时间的不确定性,用零等待策略对加工过程进行约束,建立了基于模糊规划理论的零等待Flowshop调度模型,通过中间值最大隶属度的方法,将原有的模糊调度模型转化为清晰的调度模型;最后应用改进的模拟退火算法对模型进行仿真优化,制定了适用于实际排产过程中的GANTT图,仿真结果说明了调度模型的正确性和改进算法的有效性。 展开更多
关键词 不确定性 flow shop生产调度 零等待 模糊优化 模拟退火
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柔性Flow Shop调度问题的研究现状及发展趋势 被引量:1
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作者 王莉 朱晶 《鞍山师范学院学报》 2002年第1期9-13,共5页
许多实际生产环境如石油、化工、钢铁等流程工业都是柔性FlowShop环境 .文中对柔性FlowShop调度问题的研究现状进行了评述 。
关键词 柔性flowShop 调度 数学规划 启发式算法 发展趋势 工艺流程 生产环境
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RESEARCH ON THE BLOCKING FLOW IN A TRANSPORTATION NETWORK──THE GENERAL CONCEPTS AND THEORY OF THE BLOCKING FLOW 被引量:4
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作者 Ning Xuanxi (Industry and Business College,NUAA 29 Yudao Street,Nanjing 210016,P.R.China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1994年第2期215-223,共9页
Blockage is a kind of phenomenon occurring frequently in modern transportation network. This paper deals with the research work on the blocking now in a network with the help of network flow theory. The blockage pheno... Blockage is a kind of phenomenon occurring frequently in modern transportation network. This paper deals with the research work on the blocking now in a network with the help of network flow theory. The blockage phenomena can be divided intO local blockage and network blockage. In this paper, which deals mainly with the latter, the fundamental concepts and definitions of network blocking flow, blocking outset are presented and the related theorems are proved. It is proved that the sufficient and necessary condition for the emergence of a blocking now in a network is the existence of the blocking outset. The necessary conditions for the existence of the blocking outset in a network are analysed and the characteristic cutset of blockage which reflects the all possible situation of blocking nows in the network is defined.In the last part of the paper the mathematical model of the minimum blocking now is developed and the solution to a small network is given. 展开更多
关键词 NETWORK flow NETWORK graph THEORY NETWORK now programMING BLOCKING flow
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Asymptotically Optimal Scenario Analysis and Wait-and-See Model for Optimal Power Flow With Wind Power 被引量:27
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作者 LI Jinghua WEI Hua MO Dong 《中国电机工程学报》 EI CSCD 北大核心 2012年第22期I0003-I0003,共1页
精确模拟风功率分布的场景,有效求解反映风电随机性的最优潮流模型,对大规模风电并网的经济调度、质量控制及安全运行均具有重要意义。引入风电随机变量,建立最优潮流的"wait-and-see"(WS-OPF)模型;采用优于其他指标的瓦瑟斯坦(Was... 精确模拟风功率分布的场景,有效求解反映风电随机性的最优潮流模型,对大规模风电并网的经济调度、质量控制及安全运行均具有重要意义。引入风电随机变量,建立最优潮流的"wait-and-see"(WS-OPF)模型;采用优于其他指标的瓦瑟斯坦(Wasserstein)距离为衡量指标,形成与风功率概率分布最优近似的场景模型,生成渐近最优场景,获得潮流分布及机组最优出力等指导调度安全经济运行的重要信息。最后,以IEEE 30和IEEE 300系统为例,对比各种距离指标的模拟精度,验证Wasserstein距离的优良性;同时,与不考虑风电随机性的模型相比,WS-OPF模型能更好地模拟风功率随机特性,提供与实际发生的风功率相近的调度方案,从而合理地规避风电接入电网的风险,提高风电的消纳能力。 展开更多
关键词 优化调度模型 渐近最优 最优潮流 风电 随机变量 电力系统
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Optimization model of truck flow at open-pit mines and standards for feasibility test 被引量:2
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作者 YingZhang YongZhao QiweiLu WenliXu 《Journal of University of Science and Technology Beijing》 CSCD 2004年第5期389-393,共5页
In order to increase production efficiency at open-pit mines, on the basis oflinear programming, a practical mathematical model for optimizing truck flow was developed, whichimproved the traditional fixed manual sched... In order to increase production efficiency at open-pit mines, on the basis oflinear programming, a practical mathematical model for optimizing truck flow was developed, whichimproved the traditional fixed manual schedule method. The model has advantages from linearprogramming and objective programming, makes most handling points working at full capacity and keepsan optimized ratio between trucks and excavators. For ensuring feasibility of the model inpractical production, four standards for feasibility test were proposed. The model satisfied all thestandards. The application in a large scale open-pit iron mine indicated that the model reduced thenumber of required trucks by 10 percent compared with the fixed manual schedule method. 展开更多
关键词 open-pit mine truck flow linear programming mathematical model FEASIBILITY
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Sustainable Multi-Objective Multi-Reservoir Optimization Considering Environmental Flow 被引量:1
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作者 Pushpak D. Dabhade Dattatray G. Regulwar 《Journal of Water Resource and Protection》 2021年第12期945-956,共12页
Increasing demand for water from all sectors presents a challenge for policy makers to improve water allocation policies for storage reservoirs. In addition, there are many other organisms and species present in river... Increasing demand for water from all sectors presents a challenge for policy makers to improve water allocation policies for storage reservoirs. In addition, there are many other organisms and species present in river waters that also require water for their survival. Due to the lack of awareness many times the minimum required quantity and quality of water for river ecosystem is not made available at downstream of storage reservoirs. So, a sustainable approach is required in reservoir operations to maintain the river ecosystem with environmental flow while meeting the other demands. Multi-objective, multi-reservoir operation model developed with Python programming using Fuzzy Linear Programing method incorporating environmental flow requirement of river is presented in this paper. Objective of maximization of irrigation release is considered for first run. In second run maximization of releases for hydropower generation is considered as objective. Further both objectives are fuzzified by incorporating linear membership function and solved to maximize fuzzified objective function simultaneously by maximizing satisfaction level indicator (λ). The optimal reservoir operation policy is presented considering constraints including Irrigation release, Turbine release, Reservoir storage, Environmental flow release and hydrologic continuity. Model applied for multi-reservoir system consists of four reservoirs, i.e., Jayakwadi Stage-I Reservoir (R1), Jayakwadi Stage-II Reservoir (R2), Yeldari Reservoir (R3), Siddheshwar Reservoir (R4) in Godavari River sub-basin from Marathwada region of Maharashtra State, India. 展开更多
关键词 OPTIMIZATION Multi-Objective Analysis MULTI-RESERVOIR Reservoir Operation Environmental flow Linear programming Fuzzy Logic
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A Comparative Study on Test Case Generation of Concurrent Programs
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作者 Bidush Kumar Sahoo Mitrabinda Ray 《World Journal of Engineering and Technology》 2016年第2期273-280,共8页
This paper deals with a comparative study on testing of concurrent programs based on different techniques. The various challenges in testing concurrent programming are: defining test coverage criteria based on control... This paper deals with a comparative study on testing of concurrent programs based on different techniques. The various challenges in testing concurrent programming are: defining test coverage criteria based on control flow, generating control flow graph of nondeterministic programs, investigating the applicability of sequential testing criteria to parallel program testing etc. For solving these issues, some existing techniques are discussed in this study. Various researchers use an intermediate graph called Event Inter Actions Graph (EIAG) to solve the problem of generating the control flow graph of nondeterministic programs. Some researches propose an intermediate graph called Interaction Sequence Testing Criteria (ISTC) approach based on sequence of interactions to solve the problem of test coverage criteria based on control and data flow. Another method to solve the problem of generating test coverage based on control flow graph of nondeterministic programs is constraint based approach. It needs constrained elements to generate test case which includes structural element and constraint. The selection of good test cases has been addressed by test data generation technique. The technique of concurrent path analysis approach is used to solve the problem of applicability of sequential testing criteria to parallel program testing. It reduces the number of combined concurrent test paths. The sequential test paths are combined to form concurrent test path. The Integration and System Test Automation (ISTA) approach is used to solve the problem of applicability of sequential testing criteria to parallel program testing. It is used for automated test case generation and execution by using high-level Petri net is a finite state test model. 展开更多
关键词 Concurrent program EIAG Dead Statement Control flow Graph Nondeterministic program
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Multi-Reservoir Optimization for Maximization of Releases for Hydropower Generation Considering Environmental Flow
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作者 Pushpak D. Dabhade Dattatray G. Regulwar 《Journal of Water Resource and Protection》 2021年第12期931-944,共14页
Water is the soul of the world. It is the most important element for the survival of humans, animals, birds, plants and all other living things on earth. Water is essential for the beginning of life as well as regular... Water is the soul of the world. It is the most important element for the survival of humans, animals, birds, plants and all other living things on earth. Water is essential for the beginning of life as well as regular availability of water ensuring the survival, growth and overall nourishment. Thus, proper planning and use of reservoir water are essential for all. To tackle this issue different optimization techniques underline their need and importance in the reservoir operations. In the present study, multi-reservoir optimization model is developed using Python programing language considering the objective of maximization of total annual release for hydropower generation. Model is applied to 3 reservoirs from Godavari River basin from Maharashtra state India. Water essential for conservation of environment has also been made available in river as environmental flow as per the recommendations of Central Water Commission (CWC) India. Developed optimization model provides optimal monthly operation policies. 展开更多
关键词 OPTIMIZATION MULTI-RESERVOIR Reservoir Operation Environmental flow Linear programming
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RESEARCH ON THE LOCAL BLOCKAGE OF A TRANSPORTATION NETWORK AND ITS MINIMUM FLOW CAPACITY
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作者 Ning Xuanxi(Industry and Business College ,NUAA 29 Yudao Street ,Nanjing 210016 ,P.R.China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1994年第1期60-66,共7页
This paper deals with the research work on the phenomena of local blockage in a transportation network. Onthe basis of introducing the research results in [1], theminimum now capacity problem of a network in the mosts... This paper deals with the research work on the phenomena of local blockage in a transportation network. Onthe basis of introducing the research results in [1], theminimum now capacity problem of a network in the mostseriously blocked situation is studied. With the conceptof complete outset presented in [1], the relationship between the minimum now capacity of a network and its minimum complete cut capacity is discussed, and the reasons for the difference betweent the minimum now capacity of a network and its minimum complete cut capa-city are analysed. In order to get the solution to the problem, the concepts of normalization of a network and its blocking path graph are presented. In the paper it is proved that the necessary and sufficient conditions for the equality between the minumum now capacity and its minumum complete cut capacity are the existence of a feasible flow in the blocking path graph. For the reason that there are some dependent production points in the blocking path graph of a network, the proof about the tenability of the Gale's Theorm for the planat normalized network without circuit is made. 展开更多
关键词 NETWORK flow NETWORK graph theory BLOCKING flow NETWORK now programMING
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An Interval Programming-based Traffic Planning Model for Urban Vehicle Emissions Management
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作者 Shen Wang Yulei Xie +2 位作者 Ye Tang Hongkuan Zang Zhe Wang 《Energy and Power Engineering》 2013年第4期344-349,共6页
An interval linear traffic planning model is developed for supporting vehicle emissions limited under uncertainty. The interval linear traffic planning model can address uncertainties of traffic system and vehicle emi... An interval linear traffic planning model is developed for supporting vehicle emissions limited under uncertainty. The interval linear traffic planning model can address uncertainties of traffic system and vehicle emissions related to system costs and limitation of emission. The interval linear traffic planning model is applicable to complex traffic system. One virtual city as our study object was taken by using the interval linear traffic planning model. In this study, one virtual case and a scenario are provided for three planning periods. The results indicate that the interval linear traffic planning model can effectively reduce the vehicles emission and provide strategies for authorities to deal with problems of transportation system. 展开更多
关键词 TRAFFIC System VEHICLE EMISSIONS TRAFFIC flow INTERVAL Linear programMING INTERVAL NUMBER
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城市轨道交通网络韧性优化研究 被引量:7
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作者 张开冉 殷苏平 蒋明君 《安全与环境学报》 北大核心 2025年第2期527-535,共9页
修复策略优化是提高突发事件发生后城市轨道交通网络韧性的重要手段。当前的研究多集中在单一层面的韧性评估,对乘客出行行为的考虑也较少关注对网络熟悉度的随机性。为此构建了城市轨道交通网络韧性优化双层模型,以提高网络对不利因素... 修复策略优化是提高突发事件发生后城市轨道交通网络韧性的重要手段。当前的研究多集中在单一层面的韧性评估,对乘客出行行为的考虑也较少关注对网络熟悉度的随机性。为此构建了城市轨道交通网络韧性优化双层模型,以提高网络对不利因素的应对能力。综合考虑多个层面提出了恢复速度和网络性能双韧性指标,以双韧性指标最大化为目标,考虑乘客出行行为决策,构建了基于修复策略的韧性优化双层模型。并以杭州地铁网络作为实际案例进行验证分析。结果表明:模型所求的修复策略优于其他修复策略;在一定范围内恢复速度韧性随着预算修复资金增加而减小,网络性能韧性随之增大而增大,恢复速度韧性随着修复队伍数量增大而增大,网络性能韧性随之增大而减小。 展开更多
关键词 安全系统学 城市轨道交通网络 韧性优化 客流分配 双层规划 修复策略
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考虑动态交通演化过程的应急疏散优化研究 被引量:1
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作者 王飒一 张小宁 《工程管理科技前沿》 北大核心 2025年第2期9-16,共8页
随着全球自然灾害的频繁发生,城市应急疏散策略的研究显得尤为重要。本文针对城市灾前有预警的应急疏散问题,研究考虑动态交通演化过程的应急疏散优化策略。首先,建立一个双层规划模型:下层规划为基于动态用户最优路径选择策略的多分类... 随着全球自然灾害的频繁发生,城市应急疏散策略的研究显得尤为重要。本文针对城市灾前有预警的应急疏散问题,研究考虑动态交通演化过程的应急疏散优化策略。首先,建立一个双层规划模型:下层规划为基于动态用户最优路径选择策略的多分类交通流网络模型,上层规划则通过优化疏散需求点-应急避难点匹配策略来最小化总疏散完成时间;其次,基于时空网格划分,采用一阶有限体格式求解多分类交通流网络模型,并设计启发式算法求解上层规划;再次,通过数值算例验证模型和算法的有效性。 展开更多
关键词 应急疏散 动态交通演化 双层规划 网络交通流模型 应急避难点匹配
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大型活动下城轨车站客流协同控制及优化
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作者 左忠义 杨欣然 《大连交通大学学报》 2025年第1期9-14,38,共7页
大型活动散场时段的短时大客流需求具有空间分布失衡性,易造成城市轨道交通站台出现乘客聚集现象,不仅影响乘客乘车的舒适度,还存在安全事故隐患。为解决该问题,将乘客进站与列车运行时间离散化,以乘客最佳进站人数与列车运行长短交路... 大型活动散场时段的短时大客流需求具有空间分布失衡性,易造成城市轨道交通站台出现乘客聚集现象,不仅影响乘客乘车的舒适度,还存在安全事故隐患。为解决该问题,将乘客进站与列车运行时间离散化,以乘客最佳进站人数与列车运行长短交路作为决策变量,基于客流演化与列车运行的动态关系,建立以乘客总等待时间和列车运行时间最小化为目标的多站联合限流与长短交路开行方案协同优化模型,并运用蜂群优化算法进行模型求解。以某轨道交通线路为例,验证模型的有效性。结果表明,与常规运营策略相比,协同优化策略下运营成本减少了5.3%,乘客等待时间减少了19.2%,实现了对大型活动背景下车站短时大客流的有效控制。 展开更多
关键词 城市轨道交通 多目标规划 蜂群算法 客流协同控制 优化策略
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基于程序流程图和图注意力网络的跨语言代码抄袭检测方法 被引量:2
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作者 张峰 韦友良 秦玉成 《小型微型计算机系统》 北大核心 2025年第1期249-256,共8页
跨语言代码抄袭检测在软件知识产权保护和计算机程序设计类课程教学等领域有广泛的应用.然而,不同编程语言的语法差异降低了代码之间的相似度,导致抄袭检测的准确率较低.因此,本文提出一种基于程序流程图和图注意力网络的跨语言代码抄... 跨语言代码抄袭检测在软件知识产权保护和计算机程序设计类课程教学等领域有广泛的应用.然而,不同编程语言的语法差异降低了代码之间的相似度,导致抄袭检测的准确率较低.因此,本文提出一种基于程序流程图和图注意力网络的跨语言代码抄袭检测方法.首先,将代码转换为程序流程图,并利用图注意力网络提取程序流程图的特征作为代码的表示;其次,采用交叉匹配方法逐行对比代码的表示,以获得代码的相似特征向量;最后,拼接待检测代码的相似特征向量,并通过全连接神经网络计算抄袭的概率.实验结果表明,与现有的跨语言代码抄袭检测方法相比,本文提出的方法在查准率、查全率和F1值方面均有提高.其中,与基于属性计数的CLCDSA方法、基于抽象语法树的ASTLearner方法相比,F1值分别提高了11%和16%. 展开更多
关键词 代码抄袭检测 跨编程语言 程序流程图 图注意力网络
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混合流场景下信号配时与车辆轨迹多目标联合优化方法 被引量:1
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作者 柳清泉 李萌 郭娅明 《中国公路学报》 北大核心 2025年第7期303-316,共14页
针对智能网联车辆(Intelligent Connected Vehicles, ICV)和人工网联车辆(Human-driven Connected Vehicles, HCV)并存的混合流场景,为了协调交叉口各个方向车辆复杂的冲突关系,提出了一种针对信号配时与车辆轨迹的多目标联合优化方法... 针对智能网联车辆(Intelligent Connected Vehicles, ICV)和人工网联车辆(Human-driven Connected Vehicles, HCV)并存的混合流场景,为了协调交叉口各个方向车辆复杂的冲突关系,提出了一种针对信号配时与车辆轨迹的多目标联合优化方法。在信号方面,基于非固定周期的相位设置方式,灵活组合绿灯相位,提升交通信号配时的灵活性;在轨迹方面,对ICV和HCV分别建立跟驰约束,同时预测HCV轨迹并优化ICV轨迹。最终,统一考虑车辆延误和油耗2个优化目标,建立单层联合优化模型,同时获取信号配时与车辆轨迹的全局最优解。针对混合流场景的随机性,设计了滚动时域优化方法和鲁棒机制。数值试验中,选取了多种不同的基准方案与所提方法进行对比,包括传统的信号与轨迹优化方案,以及已有研究中的双层联合优化方案,以验证求解结果的全局最优性。结果表明:相较于基准方案,所提出的单层联合优化方案在不同的ICV占有率与交通需求场景中,均能够实现最低的车辆延误和油耗;在敏感度分析试验中,对不同优化目标之间的相关关系以及模型复杂度展开了分析;试验结果揭示了在该场景下,若选取合适的权重系数,不仅能够得到帕累托最优解,还有可能得到在所有目标下均为最优或近似最优的求解结果。最后,基于珠海市交叉口数据集,验证了所提方法在强波动的交通需求下仍然能够实现较好的优化效果。 展开更多
关键词 交通工程 信号轨迹联合优化 混合整数规划 混行交通流 智能网联车辆
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考虑应急车辆优先通行的网联汽车-交叉口协同控制方法 被引量:1
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作者 蒋贤才 李梦颖 梁辰 《交通运输系统工程与信息》 北大核心 2025年第3期163-177,共15页
鉴于交通信号控制无法保证应急车辆(EMergency Vehicle, EMV)快速通行交叉口,且抢占式信号控制策略对社会车辆利益侵占严重的状况,本文基于动态公交专用道构建EMV在交叉口的空间优先通行权,提出一种网联交通环境下交叉口EMV借用冲突车... 鉴于交通信号控制无法保证应急车辆(EMergency Vehicle, EMV)快速通行交叉口,且抢占式信号控制策略对社会车辆利益侵占严重的状况,本文基于动态公交专用道构建EMV在交叉口的空间优先通行权,提出一种网联交通环境下交叉口EMV借用冲突车流绿灯时间通行的两层优化策略。上层利用网联汽车可诱导/轨迹可控的优势,以交叉口车均延误及预期车速达成度倒数的乘积最小为优化目标,建立网联汽车(Connected Vehicles, CVs)轨迹与信号配时的联合优化模型,优化交叉口的信号配时和CVs运行轨迹;下层基于优化后的信号配时,以EMV速度达成度为约束,决策协同的冲突车流及采取的绿灯借用策略。以相位绿灯时长和CVs加速度为决策变量,考虑交叉口相位间的冲突和车辆轨迹等约束条件,建立动态规划模型求解目标函数。仿真结果表明:相较于仅开展信号优化控制,借用通行策略能显著降低EMV在交叉口的行程时间;与抢占式信号控制策略相比,能极大改善社会车辆的利益侵占。研究显示,公交小时交通量是制约EMV快速通行的关键因素。 展开更多
关键词 智能交通 冲突车流绿时拆借 动态规划 网联汽车 应急车辆优先通行
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考虑动库容影响的水库发电优化调度研究
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作者 彭杨 崔永红 +1 位作者 于显亮 姚礼双 《水力发电学报》 北大核心 2025年第9期15-26,共12页
针对河道型水库动库容变化及库区干支流非恒定流传播对发电调度的影响,本文构建了一种耦合一维河网非恒定流模型的水库发电优化调度模型。该模型采用基于OpenMP的并行动态规划算法进行求解,并应用于三峡水库发电调度实例研究。结果表明... 针对河道型水库动库容变化及库区干支流非恒定流传播对发电调度的影响,本文构建了一种耦合一维河网非恒定流模型的水库发电优化调度模型。该模型采用基于OpenMP的并行动态规划算法进行求解,并应用于三峡水库发电调度实例研究。结果表明:所建模型能有效模拟三峡库区干支流河道沿程流量和水位变化过程;与静库容模型相比,动库容模型在消落期、汛期和蓄水期的发电量变化呈明显差异——消落期和汛期变化过程更平稳,而蓄水期波动幅度增大,三个时期总发电量分别减少2.06亿kW·h、1.29亿kW·h和0.47亿kW·h,其中动库容对消落期总发电量影响最大;在消落期和蓄水期调度初期,动库容模型通过增大出库流量来提高发电量。研究结果可为河道型水库发电调度精细化模拟提供参考。 展开更多
关键词 发电优化调度 河道型水库 动库容 一维河网非恒定流 并行动态规划
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逻辑流程图在小学图形化编程教学中的实践应用 被引量:1
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作者 张杰 姚磊 《科教文汇》 2025年第2期180-183,共4页
该文旨在探讨在小学图形化编程教学过程中,教师如何通过逻辑流程图来帮助小学生更好地厘清图形化编程的创作思路,直观呈现整体规划、逻辑关系和算法实现。为进一步提升学习者的计算思维能力,把引发学生思考、创设情境主题、设计逻辑流... 该文旨在探讨在小学图形化编程教学过程中,教师如何通过逻辑流程图来帮助小学生更好地厘清图形化编程的创作思路,直观呈现整体规划、逻辑关系和算法实现。为进一步提升学习者的计算思维能力,把引发学生思考、创设情境主题、设计逻辑流程、实施具体方案和反思优化总结作为实现计算思维可视化的重要切入点,结合科学系统的调试评估和巩固提升,为教师提供方法策略指导。 展开更多
关键词 图形化编程 逻辑流程图 计算思维
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