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修建乡村道路的粗骨料间断级配法
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作者 宋思东 《四川农机》 2003年第4期25-25,共1页
关键词 乡村道路 粗骨料 间断级配法 工作原理 施工质量
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集料级配防水砼的施工技术要点
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作者 辛克松 樊艳华 温晓明 《山西建筑》 2000年第2期62-64,共3页
在我们经常施工的水塔、水池工程中,要求具有良好的防水性能。有的敷设麻布沥青防水层,或沥青油毡防水层,在一些特殊的防水工程上,也有的采用金属防水层。这些虽能达到防水目的,但要增加工序,耗工耗料,实践证明:防水砼具有一定的技术经... 在我们经常施工的水塔、水池工程中,要求具有良好的防水性能。有的敷设麻布沥青防水层,或沥青油毡防水层,在一些特殊的防水工程上,也有的采用金属防水层。这些虽能达到防水目的,但要增加工序,耗工耗料,实践证明:防水砼具有一定的技术经济效果。只要增加砼自身密实度,具有较好的抗渗能力,同时起着承重和围护作用。多年来先后施工的太钢热连轧49/750m^3塔、冶金电机厂水塔、平塑40/650m^3倒锥形水塔水柜预制。 展开更多
关键词 防水混凝土 集料级配法 配合比 施工技术
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饱和砂土蠕变特性及其影响因素试验研究 被引量:3
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作者 蔡国军 陈世豪 +1 位作者 赵大安 周扬 《工程地质学报》 CSCD 北大核心 2019年第5期1048-1055,共8页
为了研究饱和砂土的蠕变特性及其影响因素,开展了不同密度、不同级配方法(相似级配法、等量替代法)、不同加载方式的侧限高压单向压缩试验。试验结果表明:饱和砂土的蠕变主要经历3个阶段,分别为瞬时变形阶段、快速变形阶段和稳态蠕变变... 为了研究饱和砂土的蠕变特性及其影响因素,开展了不同密度、不同级配方法(相似级配法、等量替代法)、不同加载方式的侧限高压单向压缩试验。试验结果表明:饱和砂土的蠕变主要经历3个阶段,分别为瞬时变形阶段、快速变形阶段和稳态蠕变变形阶段;压缩模量随密度的增大而增大;用相似级配法所制试样加权平均粒径比等量替代法所制试样的加权平均粒径小42. 4%,压缩模量高8%~18%。不同加载方式对试样的最终变形量也有一定的影响。循环加载后,试样压缩模量减小4. 3%~10. 1%,最终应变量增加4. 6%~6. 0%。对试验数据进行统计分析表明,用幂函数可以很好地拟合饱和砂土的应力、应变、时间关系,最终得到适用于本砂土的蠕变模型。研究成果可在砂土地基设计、评估中得到应用。 展开更多
关键词 相似级配法 等量替代法 蠕变特性 蠕变模型
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Experimental Study on Full-Surface Buckling of Variable Curvature Cylindrical Shell Using Multi-camera 3D-DIC System
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作者 LI Xin SUN Wei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第5期589-598,共10页
To achieve full-surface strain measurement of variable curvature objects,a 360°3D digital image correlation(DIC)system is proposed.The measurement system consists of four double-camera systems,which capture the o... To achieve full-surface strain measurement of variable curvature objects,a 360°3D digital image correlation(DIC)system is proposed.The measurement system consists of four double-camera systems,which capture the object’s entire surface from multiple angles,enabling comprehensive full-surface measurement.To increase the stitching quality,a hierarchical coordinate matching method is proposed.Initially,a 3D rigid body calibration auxiliary block is employed to track motion trajectory,which enables preliminary matching of four 3D-DIC sub-systems.Subsequently,secondary precise matching is performed based on feature points on the test specimen’s surface.Through the hierarchical coordinate matching method,the local 3D coordinate systems of each double-camera system are unified into a global coordinate system,achieving 3D surface reconstruction of the variable curvature cylindrical shell,and error analysis is conducted on the results.Furthermore,axial compression buckling experiment is conducted to measure the displacement and strain fields on the cylindrical shell’s surface.The experimental results are compared with the finite element analysis,validating the accuracy and effectiveness of the proposed multi-camera 3D-DIC measuring system. 展开更多
关键词 360°3D digital image correlation(DIC) hierarchical coordinate matching method full-field 3D deformation measurement variable curvature cylindrical shell
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基于FLAC3D的某酒厂高填方地基变形分析 被引量:4
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作者 云海浪 韩文喜 +3 位作者 张杰 魏浩 吕桂林 黄小龙 《建筑结构》 CSCD 北大核心 2021年第S02期1483-1489,共7页
以郎酒厂约40m厚的高填方工程为背景,通过室内大型试验获取填料物理力学特性与本构模型参数,分析高填方地基沉降变形机理,采用FLAC3D有限差分软件建立三维模型,利用自主开发Duncan-ChangE-B本构模型对填筑体在施工期不同高度下的沉降变... 以郎酒厂约40m厚的高填方工程为背景,通过室内大型试验获取填料物理力学特性与本构模型参数,分析高填方地基沉降变形机理,采用FLAC3D有限差分软件建立三维模型,利用自主开发Duncan-ChangE-B本构模型对填筑体在施工期不同高度下的沉降变形进行分析。结果表明:在土石比为3:7的泥质灰岩填料预测施工期高填方沉降时,Duncan-Chang E-B本构模型具有较好的适用性;施工期高填方地基沉降量随填筑高度呈指数关系增长,同时,高填方原地基所处应力也不断增大,且表现为距离基底越近所受应力越大。 展开更多
关键词 高填方地基 泥质灰岩填料 相似级配法 Duncan-Chang E-B模型 FLAC3D
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缩尺效应对粗粒料压实密度影响的试验研究 被引量:16
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作者 吴二鲁 朱俊高 +1 位作者 郭万里 陈鸽 《岩土工程学报》 EI CAS CSCD 北大核心 2019年第9期1767-1772,共6页
堆石料的级配缩尺后的试验替代料与原级配料的试验结果之间存在一定的差异,弄清这种差异对准确把握原级配堆石料的力学性质十分重要。将缩尺效应归结为最大粒径和级配结构两部分变化产生的影响。利用土的连续级配方程结合相似级配法缩... 堆石料的级配缩尺后的试验替代料与原级配料的试验结果之间存在一定的差异,弄清这种差异对准确把握原级配堆石料的力学性质十分重要。将缩尺效应归结为最大粒径和级配结构两部分变化产生的影响。利用土的连续级配方程结合相似级配法缩尺的思路,设计了大量最大粒径分别为20,40和60 mm的试验级配。对各级配粗粒料进行了表面振动压实试验,研究了最大粒径和级配结构对粗粒料压实密度的影响。最大粒径和级配结构对粗粒料压实密度的影响可以用一定的函数形式定量表述,建立了考虑缩尺效应的粗粒料压实密度的预测模型,探讨了该模型对不同性质粗粒料的适用性,并用多组室内最大干密度试验数据进行了验证。此外,提出了一种能够定量研究粗粒料缩尺效应的思路。 展开更多
关键词 粗粒料 最大粒径 相似级配法 最大干密度
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黏结性煤的管式炉降黏技术
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作者 刘巧霞 孔少亮 +3 位作者 王鹏伟 兰伟伟 王浩 王永娟 《化学工程》 CAS CSCD 北大核心 2023年第7期66-71,共6页
黏结性煤可以通过选择合适的降黏工艺拓宽应用范围。以韩城煤为原料,在管式炉中开展了预氧化法、添加剂法及不黏煤级配法3种降黏方法的研究,将黏结指数降至5以下。研究结果表明:预氧化法适宜条件为温度200—250℃,气氛为空气,流量50—50... 黏结性煤可以通过选择合适的降黏工艺拓宽应用范围。以韩城煤为原料,在管式炉中开展了预氧化法、添加剂法及不黏煤级配法3种降黏方法的研究,将黏结指数降至5以下。研究结果表明:预氧化法适宜条件为温度200—250℃,气氛为空气,流量50—500 mL/min,停留时间小于30 min;添加剂选用NaOH和H_(3)BO_(3),NaOH添加质量比为3%,H_(3)BO_(3)添加质量比为2%;不黏煤级配法中,新疆煤、锦界煤、彬长煤添加质量比为30%。结合SEM、热重及红外分析,证明不同降黏方法的降黏原理不同,但3种方法均可将韩城煤由黏结煤变为不黏煤,从而拓宽煤的应用范围。 展开更多
关键词 黏结性煤 预氧化法 添加剂法 级配法
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An Approach to Unsupervised Character Classification Based on Similarity Measure in Fuzzy Model
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作者 卢达 钱忆平 +1 位作者 谢铭培 浦炜 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期370-376,共7页
This paper presents a fuzzy logic approach to efficiently perform unsupervised character classification for improvement in robustness, correctness and speed of a character recognition system. The characters are first ... This paper presents a fuzzy logic approach to efficiently perform unsupervised character classification for improvement in robustness, correctness and speed of a character recognition system. The characters are first split into eight typographical categories. The classification scheme uses pattern matching to classify the characters in each category into a set of fuzzy prototypes based on a nonlinear weighted similarity function. The fuzzy unsupervised character classification, which is natural in the repre... 展开更多
关键词 fuzzy model weighted fuzzy similarity measure unsupervised character classification matching algorithm classification hierarchy
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Design of dense gap-graded friction course mixture 被引量:2
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作者 吴旷怀 张肖宁 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期101-105,共5页
The design procedure of a dense gap-graded friction course(DGGFC) with coarse aggregate void filling method is presented. Testing results show that a DGGFC mixture possesses a dense stone-matrix structure, good stab... The design procedure of a dense gap-graded friction course(DGGFC) with coarse aggregate void filling method is presented. Testing results show that a DGGFC mixture possesses a dense stone-matrix structure, good stability and almost the same texture depth as stone matrix asphalt (SMA). It also has a coarse and even surface after paving and has no separation during construction. It is durable and impermeable. It balances and improves the inherent inconsistency of asphalt mixture between the large texture depth for skid resistance and the impermeability for durability. The actual application in the Nanning-Liuzhou Expressway also shows that the performance of the DGGFC is as excellent as that of SMA, while the DGGFC mixture is cheaper than SMA. The DGGFC mixture is good for wearing course of pavement. Further research on DGGFC can be helpful for improving the surface skid resistance, prolonging the life-span period and reducing the construction costs of asphalt pavement. 展开更多
关键词 dense gap-graded friction course (DGGFC) coarse aggregate void filling method dense stonematrix structure pavement performance
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混凝土合理砂率的选择分析
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作者 王达剑 《建筑技术开发》 2014年第6期68-72,共5页
对于坍落度为10~60mm的低塑性、塑性混凝土,对比分析了试验法、查表法、计算法、砂石整体级配法,在应用时,应综合考虑影响合理砂率选择的因素,较准确地选择合理砂率,以达到混凝土的技术经济性。
关键词 混凝土 配合比 砂率 试验法 查表法 计算法 砂石整体级配法
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Nonlinear Auto-Companding Method for Behavioral Modeling of Switched-Current Circuits
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作者 王伟 曾璇 +2 位作者 陶俊 苏仰峰 唐璞山 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第12期1254-1261,共8页
A wavelet collocation method with nonlinear auto companding is proposed for behavioral modeling of switched current circuits.The companding function is automatically constructed according to the initial error distri... A wavelet collocation method with nonlinear auto companding is proposed for behavioral modeling of switched current circuits.The companding function is automatically constructed according to the initial error distribution obtained through approximating the input output function of the SI circuit by conventional wavelet collocation method.In practical applications,the proposed method is a general purpose approach,by which both the small signal effect and the large signal effect are modeled in a unified formulation to ease the process of modeling and simulation.Compared with the published modeling approaches,the proposed nonlinear auto companding method works more efficiently not only in controlling the error distribution but also in reducing the modeling errors.To demonstrate the promising features of the proposed method,several SI circuits are employed as examples to be modeled and simulated. 展开更多
关键词 wavelet collocation method behavioral modeling switched current circuits nonlinear auto companding
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风化料的强度与变形特性及其影响因素分析
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作者 刘衍林 石颖 《徐州建筑职业技术学院学报》 2009年第4期5-8,共4页
按照相似级配法将风化料的粒径缩小后,进行物理力学性质试验研究,并采用干湿循环模拟风化料的进一步风化进行试验.基于此,探讨了风化料的强度特性和变形特性,对风化料快速法与常速法压缩试验的结果进行了比较,分析了影响凤化料强度和变... 按照相似级配法将风化料的粒径缩小后,进行物理力学性质试验研究,并采用干湿循环模拟风化料的进一步风化进行试验.基于此,探讨了风化料的强度特性和变形特性,对风化料快速法与常速法压缩试验的结果进行了比较,分析了影响凤化料强度和变形特性的各种因素. 展开更多
关键词 风化料 相似级配法 干湿循环 强度 变形
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Optimal Dispatching of Large-scale Water Supply System 被引量:3
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作者 吕谋 SONG Shuang +1 位作者 Zhao Hongbin ZHANG Tuqiao 《High Technology Letters》 EI CAS 2003年第2期21-26,共6页
This paper deals with the use of optimal control techniques in large-scale water distribution networks. According to the network characteristics and actual state of the water supply system in China, the implicit model... This paper deals with the use of optimal control techniques in large-scale water distribution networks. According to the network characteristics and actual state of the water supply system in China, the implicit model, which may be solved by utilizing the hierarchical optimization method, is established. In special, based on the analyses of the water supply system containing variable-speed pumps, a software tool has been developed successfully. The application of this model to the city of Shenyang (China) is compared to experiential strategy. The results of this study show that the developed model is a very promising optimization method to control the large-scale water supply systems. 展开更多
关键词 optimal dispatching water supply system water networks implicit model hierarchical optimization
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Hierarchical Domain Assignment BaseC on Word-Gloss 被引量:1
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作者 朱朝勇 黄河燕 史树敏 《China Communications》 SCIE CSCD 2012年第3期19-27,共9页
This paper proposes a hierarchical word domain assignment algorithm to automatically build domain dictionaries from Machine-Readable Dictionary(MRD).The process for word domain assignment can be divided into three ste... This paper proposes a hierarchical word domain assignment algorithm to automatically build domain dictionaries from Machine-Readable Dictionary(MRD).The process for word domain assignment can be divided into three steps:1) Hierarchical structure constructing;2) Classifier training;3) Word domain assigning.Compared with the traditional methods,the hierarchical word domain assignment algorithm enhances the accuracy of word domain assignment while reducing human efforts on collecting corpus.Experiments on WordNet 2.0 show that 62.53% of the first domain labels are matched with the WordNet Domains 3.0 by using gloss-based word domain assignment,and the performance can be further improved by utilizing the hierarchical relationships among the domain sets. 展开更多
关键词 natural language processing domaindictionary hierarchical classification domain as-sigrmaent WORDNET MRD
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Three-dimensional analysis of a thick FGM rectangular plate in thermal environment 被引量:9
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作者 陈伟球 边祖光 丁皓江 《Journal of Zhejiang University Science》 EI CSCD 2003年第1期1-7,共7页
The thermal behavior of a thick transversely isotropic FGM rectangular plate was investigated within the scope of three-dimensional elasticity. Noticing many FGMs may have temperature-dependent properties, the materia... The thermal behavior of a thick transversely isotropic FGM rectangular plate was investigated within the scope of three-dimensional elasticity. Noticing many FGMs may have temperature-dependent properties, the material constants were further considered as functions of temperature. A solution method based on state-space formulations with a laminate approximate model was proposed. For a thin plate, the method was clarified by comparison with the thin plate theory. The influences of material inhomogeneity and temperature-dependent characteristics were finally discussed through numerical examples. 展开更多
关键词 Functionally graded material (FGM) State space method Simply supported rectangular plate
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Rule-based scheduling of multi-stage multi-product batch plants with parallel units 被引量:2
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作者 Bin Shi Xinrui Qian +1 位作者 Shanshan Sun Liexiang Yan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第8期1022-1036,共15页
A novel rule-based model for multi-stage multi-product scheduling problem(MMSP)in batch plants with parallel units is proposed.The scheduling problem is decomposed into two sub-problems of order assignment and order s... A novel rule-based model for multi-stage multi-product scheduling problem(MMSP)in batch plants with parallel units is proposed.The scheduling problem is decomposed into two sub-problems of order assignment and order sequencing.Firstly,hierarchical scheduling strategy is presented for solving the former sub-problem,where the multi-stage multi-product batch process is divided into multiple sequentially connected single process stages,and then the production of orders are arranged in each single stage by using forward order assignment strategy and backward order assignment strategy respectively according to the feature of scheduling objective.Line-up competition algorithm(LCA)is presented to find out optimal order sequence and order assignment rule,which can minimize total flow time or maximize total weighted process time.Computational results show that the proposed approach can obtain better solutions than those of the literature for all scheduling problems with more than 10 orders.Moreover,with the problem size increasing,the solutions obtained by the proposed approach are improved remarkably.The proposed approach has the potential to solve large size MMSP. 展开更多
关键词 Line-up competition algorithm Order assignment role Multi-stage multi-product Parallel unit Scheduling optimization
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Establishment of Knowledge Base Management System and the Type Selection of Mechanism for Mechanism Kinematic Scheme
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作者 叶志刚 邹慧君 +4 位作者 郭为忠 胡松 田永利 王生泽 唐林 《Journal of Donghua University(English Edition)》 EI CAS 2003年第4期145-149,共5页
Firstly data standardization technology and combined classification method have been applied to carry out classification of kinematic behaviors and mechanisms in the mapping field between the kinematic behavior level ... Firstly data standardization technology and combined classification method have been applied to carry out classification of kinematic behaviors and mechanisms in the mapping field between the kinematic behavior level and the mechanism level of conceptual design.The principle of computer coding and storing have been built to give a fast and broad selection of mechanisms that meets the requirements of basic motion characters.Then on the basis of mentioned above,the heuristic matching propagation principle (HMPP) of kinematic behaviors and its true table serves as a guide to perform mechanism types selection.Finally an application is given to indicate its practicability and effectiveness. 展开更多
关键词 conceptual design knowledge base function unit the type selection of mechanism mechanism kinematic scheme kinematic behavior
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两种粗粒土的比较试验 被引量:19
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作者 李凤鸣 卞富宗 《勘察科学技术》 1991年第2期25-29,共5页
本文对同一岩性按相似级配法制备的两种粗粒土,在试验条件基本相同的情况下,分别进行比重、于容重、固结和三轴剪切试验,并对试验结果进行了对比分析。
关键词 土工 试验 堆石料 相似级配法
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超粒径土石混合料最大干密度的试验研究 被引量:3
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作者 周志军 杨荣尚 马小伟 《公路》 北大核心 2007年第4期5-11,共7页
采用自行研制的大型击实仪对超粒径土石混合料进行击实试验,同时对土石混合料超粒径部分采用剔除法、相似级配法及等量替换法处理后进行中型击实试验,根据试验结果,提出采用等量替换法可间接求出超粒径土石混合料最大干密度的结论。其次... 采用自行研制的大型击实仪对超粒径土石混合料进行击实试验,同时对土石混合料超粒径部分采用剔除法、相似级配法及等量替换法处理后进行中型击实试验,根据试验结果,提出采用等量替换法可间接求出超粒径土石混合料最大干密度的结论。其次,对于连续级配的土石混合料,采用剔除法处理其超粒径部分,得出不同最大粒径下的松装密度、干燥密度、最大干密度和最佳含水量,从而提出剔除法处理超粒径土石混合料的最大干密度确定方法。最后综合比较等量替换法和剔除法的优缺点及适用条件,提出超粒径土石混合料最大干密度的确定方法。 展开更多
关键词 道路工程 土石混合料 剔除法 等量替换法 相似级配法 最大干密度
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A GA Based Algorithm to Solve the Multi-stage Supply Chain Optimization Problem
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作者 Fanrong Xie Renan Jia 《Journal of Systems Science and Information》 2007年第4期405-418,共14页
The multi-stage supply chain optimization problem is an important subject for research. Syaxif et al. have studied the problem formulated by a 0-1 mixed integer linear programming model, and presented a st-GA (spanni... The multi-stage supply chain optimization problem is an important subject for research. Syaxif et al. have studied the problem formulated by a 0-1 mixed integer linear programming model, and presented a st-GA (spanning tree-based genetic algorithm) by using Priifer number representation as the solution method of the model. On the basis of the work done by Syarif et al., a rst-GA (revised st-GA ) to solve the multi-stage supply chain optimization problem, is presented in this paper by means of introducing new sym- metric encoding & decoding procedures of Priifer number, and adopting new chromosome's decoding strategy, etc. To facilitate building related decision-making support system, a C language implementation method of the rst-GA is also presented in this paper. Numerical experiments have validated that the rst-GA has better performance than the st-GA. 展开更多
关键词 LOGISTICS supply chain management genetic algorithm production/distribution system
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