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Method of Establishing Object-Oriented System Structure for Decision Support System 被引量:2
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作者 曹元大 胡军 管春 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期311-315,共5页
In order to solve existing problems about the method of establishing traditional system structure of decision support system(DSS), O S chart is applied to describe object oriented system structure of general DSS, an... In order to solve existing problems about the method of establishing traditional system structure of decision support system(DSS), O S chart is applied to describe object oriented system structure of general DSS, and a new method of eight specific steps is proposed to establish object oriented system structure of DSS by using the method of O S chart, which is applied successfully to the development of the DSS for the energy system ecology engineering research of the Wangheqiu country. Supplying many scientific effective computing models, decision support ways and a lot of accurate reliable decision data, the DSS plays a critical part in helping engineering researchers to make correct decisions. Because the period for developing the DSS is relatively shorter, the new way improves the efficiency of establishing DSS greatly. It also makes the DSS of system structure more flexible and easy to expand. 展开更多
关键词 decision support system object oriented technology system structure
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Oriented Bounding Box Object Detection Model Based on Improved YOLOv8
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作者 ZHAO Xin-kang SI Zhan-jun 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期67-75,114,共10页
In the study of oriented bounding boxes(OBB)object detection in high-resolution remote sensing images,the problem of missed and wrong detection of small targets occurs because the targets are too small and have differ... In the study of oriented bounding boxes(OBB)object detection in high-resolution remote sensing images,the problem of missed and wrong detection of small targets occurs because the targets are too small and have different orientations.Existing OBB object detection for remote sensing images,although making good progress,mainly focuses on directional modeling,while less consideration is given to the size of the object as well as the problem of missed detection.In this study,a method based on improved YOLOv8 was proposed for detecting oriented objects in remote sensing images,which can improve the detection precision of oriented objects in remote sensing images.Firstly,the ResCBAMG module was innovatively designed,which could better extract channel and spatial correlation information.Secondly,the innovative top-down feature fusion layer network structure was proposed in conjunction with the Efficient Channel Attention(ECA)attention module,which helped to capture inter-local cross-channel interaction information appropriately.Finally,we introduced an innovative ResCBAMG module between the different C2f modules and detection heads of the bottom-up feature fusion layer.This innovative structure helped the model to better focus on the target area.The precision and robustness of oriented target detection were also improved.Experimental results on the DOTA-v1.5 dataset showed that the detection Precision,mAP@0.5,and mAP@0.5:0.95 metrics of the improved model are better compared to the original model.This improvement is effective in detecting small targets and complex scenes. 展开更多
关键词 Remote sensing image oriented bounding boxes object detection Small target detection YOLOv8
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OBJECT ORIENTED DATA MODELLING WITH APPLICATIONS TO CAD
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作者 应维云 傅向阳 周儒荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期69+63-68,共7页
An object oriented data modelling in computer aided design (CAD) databases is focused. Starting with the discussion of data modelling requirements for CAD applications, appropriate data modelling features are introdu... An object oriented data modelling in computer aided design (CAD) databases is focused. Starting with the discussion of data modelling requirements for CAD applications, appropriate data modelling features are introduced herewith. A feasible approach to select the “best” data model for an application is to analyze the data which has to be stored in the database. A data model is appropriate for modelling a given task if the information of the application environment can be easily mapped to the data model. Thus, the involved data are analyzed and then object oriented data model appropriate for CAD applications are derived. Based on the reviewed object oriented techniques applied in CAD, object oriented data modelling in CAD is addressed in details. At last 3D geometrical data models and implementation of their data model using the object oriented method are presented. 展开更多
关键词 computer aided design DATABASES data models object oriented data models complex objects geometrical models
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DESIGN OF WINDOW BASED AND OBJECT ORIENTED GUI
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作者 李光耀 周来水 周儒荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期74+70-73,共5页
This paper discusses the design concept and method about window based and object oriented Graphic User Interface(GUI),and describes the definition of each class in detail. It is developed with Watcom C ++ in... This paper discusses the design concept and method about window based and object oriented Graphic User Interface(GUI),and describes the definition of each class in detail. It is developed with Watcom C ++ in DOS environment.The GUI can be redeveloped conveniently and effectively by users.It consists of window,popup menu,icon,button and other components. 展开更多
关键词 USERS user interfaces graphic user interface object oriented event handle
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Temperature Field Reconstruction in High-Temperature Gas by Using the Colored Background Oriented Schlieren Method
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作者 Jun Wu Haitao Xu +3 位作者 Fengcheng Song Jun Xu Yanling Li Tao Wang 《Journal of Beijing Institute of Technology》 EI CAS 2020年第3期425-434,共10页
A 3D temperature field reconstruction method using the colored background oriented schlieren(CBOS)method is proposed to address image blurring due to the different refractive index of the multi-wavelength light and si... A 3D temperature field reconstruction method using the colored background oriented schlieren(CBOS)method is proposed to address image blurring due to the different refractive index of the multi-wavelength light and significant errors produced when the traditional background oriented schlieren(BOS)method is applied to high-temperature gas.First,the traditional method is employed to reconstruct the non-uniform 3D temperature field.Second,the CBOS method is applied to correct the distortion.Then,by analyzing the correlation coefficient among different color points of the colored background pattern,the non-uniform temperature field is reconstructed much more accurately.Finally,the experimental results are verified by applying the Runge-Kutta ray-tracing method and the thermocouple contact measurement method.The maximum average temperature error of the CBOS-reconstructed temperature field is 12.92°C,compared with the thermocouples.Therefore,an accurate three-dimensional reconstruction of the temperature field can be achieved by the proposed method effectively. 展开更多
关键词 3D temperature field reconstruction colored background oriented schlieren method ABEL inverse transform image processing
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Investment Objectives and Priorities of China Petroleum Industry Oriented to 2000
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作者 Peng Qing(Beijing Petroleum Managers Training Institute)Subjects: Investment, Decision analysis, External Cooperation 《China Oil & Gas》 CAS 1998年第2期70-72,共3页
关键词 2010 Investment objectives and Priorities of China Petroleum Industry oriented to 2000
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Development of the Object-Oriented Reservoir Description Systems in China
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作者 Zhang Xuewen and Liu Yu(Research Institute of petroleum Exploration and Development) 《China Oil & Gas》 CAS 1998年第3期161-162,共2页
关键词 object-oriented SOFTWARE DEVELOPMENT RESERVOIR DESCRIPTION
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Object-Oriented Wavelet-Layered Digital Watermarking Technique
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作者 刘晓云 虞厥邦 李明玉 《Journal of Electronic Science and Technology of China》 2005年第2期116-119,共4页
In this paper, an object-oriented digital watermarking technique is proposed in the wavelet domain for still images. According to the difference of recognition degree of the human eye to the different region of the im... In this paper, an object-oriented digital watermarking technique is proposed in the wavelet domain for still images. According to the difference of recognition degree of the human eye to the different region of the image, the image is divided into the interested region and uninterested region of human eye vision in this scheme. Using the relativity of position and the difference to ocular sensitivity of the multiresolution wavelet among each subband, the image is processed with layered watermarking append technique. Experimental results show that the proposed technique successfully survives image processing operations, additive noise and JPEG compression. 展开更多
关键词 digital watermarking object-oriented wavelet transformation ocular masking
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Behavior——oriented Teaching Method and English Curriculum Reform of Vocational Education
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作者 曾海波 《海外英语》 2017年第2期239-240,共2页
This thesis introduces the Behavior-oriented teaching method and the principles of curriculum reform in Vocational English.It mainly discusses the application of behavior oriented teaching method in the reform of Voca... This thesis introduces the Behavior-oriented teaching method and the principles of curriculum reform in Vocational English.It mainly discusses the application of behavior oriented teaching method in the reform of Vocational English Education,and refers problems and suggestions. 展开更多
关键词 Behavior-oriented teaching method Vocational English reform of education application
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Partitioning characteristics of gas channel of coal-rock mass in mining space and gas orientation method 被引量:8
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作者 Zhao Zhiqiang Ma Nianjie +1 位作者 Jia Housheng Cheng Yuanping 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期873-877,共5页
In order to research the influence of coal-rock mass morphology of mining space on the flow law of gas,the laboratory physical model and numerical computation methods were adopted to simulate coal mining activities.Th... In order to research the influence of coal-rock mass morphology of mining space on the flow law of gas,the laboratory physical model and numerical computation methods were adopted to simulate coal mining activities.The simulation results indicate that,after coal seam mining,the loose rock accumulation body of free caving,ordered rock arrangement body of plate damage rich in longitudinal and transverse fractures and horizontal fissure body formed by rock mass deformation imbalance are formed from bottom to top in the mining space.For these three types of accumulation bodies,there are essential differences in the accumulation state,rock size and gas breakover characteristics.According to this,the coal-rock mass in the mining space is classified into gas turbulence channel area,gas transitional flow channel area and gas seepage channel area.In the turbulence channel area,the gas is distributed transversely and longitudinally and gas diffuses in the form of convection with Reynolds number R_e more than100;in the transitional flow channel area,one-way or two-way gas channels are crisscross and gas is of transitional flow regime with R,.between 10 and 100.In the seepage channel area,there are a few vertical gas channels with R,.less than 10.In this paper,the researches on the gas orientation method in different partitions were further carried out,gas orientation methods of low-level pipe burying,middle-level interception and high-level extraction were determined and an on-site industrial test was conducted,achieving the effective diversion of gas and verifying the reasonableness of gas channel partition. 展开更多
关键词 Gas channel Partitioning characteristics Gas flow regime Gas orientation method
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Selection Method of Multi-Objective Problems Using Genetic Algorithm in Motion Plan of AUV 被引量:3
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作者 ZHANG Ming-jun , ZHENG Jin-xing , ZHANG Jing College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin 150001 ,China College of Computer and Information Science, Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2002年第1期81-86,共6页
To research the effect of the selection method of multi — objects genetic algorithm problem on optimizing result, this method is analyzed theoretically and discussed by using an autonomous underwater vehicle (AUV) as... To research the effect of the selection method of multi — objects genetic algorithm problem on optimizing result, this method is analyzed theoretically and discussed by using an autonomous underwater vehicle (AUV) as an object. A changing weight value method is put forward and a selection formula is modified. Some experiments were implemented on an AUV, TwinBurger. The results shows that this method is effective and feasible. 展开更多
关键词 AUV multi objective optimization genetic algorithm selection method
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Precise Object Detection Using Iterative Superpixels Grouping Method
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作者 Cheng-Chang Lien Yu-Wei Lin +2 位作者 Huan-Po Hsu Kun-Ming Yu Ming-Yuan Lei 《Journal of Electronic Science and Technology》 CAS CSCD 2017年第2期153-160,共8页
The region completeness of object detection is very crucial to video surveillance, such as the pedestrian and vehicle identifications. However, many conventional object detection approaches cannot guarantee the object... The region completeness of object detection is very crucial to video surveillance, such as the pedestrian and vehicle identifications. However, many conventional object detection approaches cannot guarantee the object region completeness because the object detection can be influenced by the illumination variations and clustering backgrounds. In order to overcome this problem, we propose the iterative superpixels grouping (ISPG) method to extract the precise object boundary and generate the object region with high completeness after the object detection. First, by extending the superpixel segmentation method, the proposed ISPG method can improve the inaccurate segmentation problem and guarantee the region completeness on the object regions. Second, the multi- resolution superpixel-based region completeness enhancement method is proposed to extract the object region with high precision and completeness. The simulation results show that the proposed method outperforms the conventional object detection methods in terms of object completeness evaluation. 展开更多
关键词 Index Terms-lterative superpixels grouping method (ISPG) object completeness object detection superpixel video surveillance.
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Density and temperature reconstruction of a flame-induced distorted flow field based on background-oriented schlieren(BOS) technique 被引量:3
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作者 郭广明 刘洪 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期203-212,共10页
An experimental system based on the background-oriented schlieren(BOS) technique is built to reconstruct the density and temperature distribution of a flame-induced distorted flow field which has a density gradient.... An experimental system based on the background-oriented schlieren(BOS) technique is built to reconstruct the density and temperature distribution of a flame-induced distorted flow field which has a density gradient. The cross-correlation algorithm with sub-pixel accuracy is introduced and used to calculate the background-element displacement of a disturbed image and a fourth-order difference scheme is also developed to solve the Poisson equation. An experiment for a disturbed flow field caused by a burning candle is performed to validate the built BOS system and the results indicate that density and temperature distribution of the disturbed flow field can be reconstructed accurately. A notable conclusion is that in order to make the reconstructed results have a satisfactory accuracy, the inquiry step length should be less than the size of the interrogation window. 展开更多
关键词 background-oriented schlieren density reconstruction finite difference methods distorted flow field
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METHOD OF CENTERS ALGORITHM FORMULTI-OBJECTIVE PROGRAMMING PROBLEMS
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作者 Tarek Emam 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1128-1142,共15页
In this paper, we consider a method of centers for solving multi-objective programming problems, where the objective functions involved are concave functions and the set of feasible points is convex. The algorithm is ... In this paper, we consider a method of centers for solving multi-objective programming problems, where the objective functions involved are concave functions and the set of feasible points is convex. The algorithm is defined so that the sub-problems that must be solved during its execution may be solved by finite-step procedures. Conditions are given under which the algorithm generates sequences of feasible points and constraint multiplier vectors that have accumulation points satisfying the KKT conditions. Finally, we establish convergence of the proposed method of centers algorithm for solving multiobjective programming problems. 展开更多
关键词 method of centers MULTI-objectIVE CONVERGENCE approximated efficient solution
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Bridge Engineering-Oriented Parametric Model
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作者 周凌远 李乔 《Journal of Southwest Jiaotong University(English Edition)》 2004年第1期61-64,共4页
A new model is proposed to improve the efficiency of structural modeling. In this model, the bridge structural components are expressed with component description, parametric description and geometric description in a... A new model is proposed to improve the efficiency of structural modeling. In this model, the bridge structural components are expressed with component description, parametric description and geometric description in a software system. This model provides both convenience and flexibility for users in structural modeling process. The object-oriented method is applied in the model implementation. A bridge analysis preprocessor is developed on the basis of this model. It provides an effective way for bridge modeling. 展开更多
关键词 engineering-oriented modeling Parametric CAD Bridge structural analysis preprocess Structural modeling Finite element method Structural analysis
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基于组合赋权的长江上游山洪风险评估——以嘉陵江流域为例
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作者 张文婷 廖婷婷 +3 位作者 张行南 刘永志 张涛 曹雨农 《长江科学院院报》 北大核心 2025年第2期76-82,99,共8页
采用主客观赋权法和博弈论相结合的方法来评估嘉陵江流域的山洪风险。结果显示,4种客观赋权法得到的洪水危险性分布总体相似,但不同方法的风险等级面积占比略有差异,CRITIC权重法识别出更多的高危险性区域。故选择CRITIC权重法、层次分... 采用主客观赋权法和博弈论相结合的方法来评估嘉陵江流域的山洪风险。结果显示,4种客观赋权法得到的洪水危险性分布总体相似,但不同方法的风险等级面积占比略有差异,CRITIC权重法识别出更多的高危险性区域。故选择CRITIC权重法、层次分析法和博弈论相结合,形成组合权重评估得到嘉陵江流域山洪综合风险的空间分布。整体而言,嘉陵江流域的山洪风险呈现出自西北向东南递增的趋势,高危险性地区主要分布在四川盆地及其边缘,涉及四川、重庆等22个县区,而低危险性地区则主要位于流域西北部山丘区。影响山洪风险的因素中,年平均降雨、径流深等致灾条件对山洪风险贡献最大,其次是人口密度和国内生产总值(GDP)等社会经济因素,而坡度、地形起伏度等下垫面条件的贡献最低。研究结果对包括嘉陵江流域在内的长江上游流域的山洪管理和应对提供重要参考。 展开更多
关键词 山洪 风险评估 主客观赋权法 博弈论 嘉陵江流域
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技术应用型人才标准化培养模式研究
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作者 田慧芹 高荧 《中国标准化》 2025年第4期228-230,共3页
为提升技术应用型人才培养质量,本研究通过问卷调查法,深入分析了现有培养模式存在的问题,包括培养目标不明确、课程设置与产业需求脱节、实践教学环节薄弱等。基于此,提出了一套培养模式标准化构建方案,包括设计标准化框架、制定优化... 为提升技术应用型人才培养质量,本研究通过问卷调查法,深入分析了现有培养模式存在的问题,包括培养目标不明确、课程设置与产业需求脱节、实践教学环节薄弱等。基于此,提出了一套培养模式标准化构建方案,包括设计标准化框架、制定优化方案与实施路径、建立评估机制与改进策略。希望通过技术应用型人才培养模式的标准化建设,提升人才培养质量,满足产业对高素质技术人才的需求,为经济转型、产业升级提供人才支撑。 展开更多
关键词 评估机制 培养目标 标准化流程 技术应用型人才
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基于不同目标函数的WRF-Hydro模型参数敏感性研究
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作者 谷黄河 石怀轩 +2 位作者 孙敏涛 丁震 顾苏烨 《中国农村水利水电》 北大核心 2025年第1期61-69,共9页
水文与气象预报相结合可以有效提高洪水预报的精度和延长预见期,陆气耦合模型已成为水文气象学者研究的重点。WRF-Hydro模型作为新一代分布式陆气耦合模型在多尺度洪水预报中具有广阔的应用前景,但由于各物理过程参数化方案复杂,模型计... 水文与气象预报相结合可以有效提高洪水预报的精度和延长预见期,陆气耦合模型已成为水文气象学者研究的重点。WRF-Hydro模型作为新一代分布式陆气耦合模型在多尺度洪水预报中具有广阔的应用前景,但由于各物理过程参数化方案复杂,模型计算量大,对该模型的参数敏感性研究还不充分,也影响着模型的模拟精度。研究以湿润区的新安江上游屯溪流域为研究对象,构建多个单目标和多目标函数,并结合Morris全局参数敏感性分析方法,探究了WRF-Hydro模型在不同目标函数下的参数敏感性。结果表明:土壤参数(DKSAT、SMCMAX、BEXP)主要影响壤中流和地表径流,对径流量影响显著,尤其DKSAT最为敏感,直接影响水在土壤中的下渗速度,增大时基流量显著增高而洪峰流量则明显降低;产流参数(SLOPE、REFKDT)主要影响地表径流和基流分配,对洪水过程线形状有重要影响;河道汇流参数ManN影响汇流速度并主要控制峰现时间;植被参数MP对于总水量有一定影响;坡面汇流参数OVROUGHRTFAC和地下水参数Zmax则最不敏感。不同目标函数下的参数敏感性顺序和最优参数取值有一定差异,单目标函数中以相对误差为优化目标会更侧重于全年径流总量和低流量部分的模拟精度,而以效率系数和Kling-Gupta系数为目标则更侧重于场次洪水和高流量部分的模拟效果;基于几个单目标函数组合的多目标函数综合考虑了不同目标函数的影响,结果在一定程度上优于单目标函数。研究可为合理确定WRF-Hydro模型参数优化策略提供参考。 展开更多
关键词 WRF-Hydro模型 Morris法 敏感性分析 多目标函数 洪水预报
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基于熵权-TOPSIS法的风光柴储互补发电系统容量优化配置
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作者 高建强 张浩 危日光 《动力工程学报》 北大核心 2025年第2期300-306,共7页
以某地区风光柴储互补发电系统为研究对象,将系统总成本和负荷缺电率作为优化目标,建立容量优化配置模型。采用多目标灰狼算法(MOGWO)对模型进行优化,将优化结果与多目标粒子群算法(MOPSO)的优化结果进行对比。同时,采用熵权-优劣解距离... 以某地区风光柴储互补发电系统为研究对象,将系统总成本和负荷缺电率作为优化目标,建立容量优化配置模型。采用多目标灰狼算法(MOGWO)对模型进行优化,将优化结果与多目标粒子群算法(MOPSO)的优化结果进行对比。同时,采用熵权-优劣解距离(TOPSIS)多目标决策法对优化解集进行筛选,降低了主观因素对权重系数的影响,增强了最优方案的合理性。结果表明:与MOPSO相比,MOGWO优化精度更高;在算例分析中,系统最优配置方案为风力发电机37台,光伏电池836块,柴油发电机5台,蓄电池531块,系统总成本116.904万元。 展开更多
关键词 风光柴储互补发电系统 容量配置 熵权-TOPSIS法 多目标灰狼算法
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应急疏散条件下车辆路径问题的多目标优化
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作者 郭瑞军 刘悦 +1 位作者 窦玉林 刘莹莹 《石家庄铁道大学学报(自然科学版)》 2025年第1期91-96,共6页
近年来,国内外灾害性突发事件频发,有必要提前制定科学合理的应急疏散计划,而应急疏散路线是应急预案的重要组成部分。首先,构建了一个在多目标优化框架下的疏散模型,该模型着手在最短时间内完成疏散和最大限度降低疏散过程中的风险;然... 近年来,国内外灾害性突发事件频发,有必要提前制定科学合理的应急疏散计划,而应急疏散路线是应急预案的重要组成部分。首先,构建了一个在多目标优化框架下的疏散模型,该模型着手在最短时间内完成疏散和最大限度降低疏散过程中的风险;然后,通过线性加权法的方式对2个目标赋予权重,在考虑疏散路网道路通行能力的前提下,将多目标转化为单目标,并通过Lingo进行求解。针对毒气泄漏事件进行了实例模拟,结果显示,综合考虑风险和时间双目标的目标值为165.12,相较于只考虑最小风险降低了99。同传统只考虑单一因素相比,优先选择风险和距离较小的路径是相对较优的策略,可综合提高应急疏散的效率,为日后应急疏散方案的制定与演练提供优化思路。 展开更多
关键词 应急疏散 路径优化 多目标模型 线性加权法 LINGO
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