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需求可拆分的多周期订货-运输集成优化算法 被引量:3
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作者 刘琼 许金辉 +1 位作者 张超勇 李俊 《计算机集成制造系统》 EI CSCD 北大核心 2013年第10期2599-2606,共8页
鉴于目前多周期订货—运输集成问题研究几乎都假设需求不可拆分、造成不能有效降低总成本,或者将车辆数作为能力约束,造成企业各计划期内需求变化较大时不便于合理设置车辆数等问题,提出一个需求可拆分、动态车辆数的多周期订货—运输... 鉴于目前多周期订货—运输集成问题研究几乎都假设需求不可拆分、造成不能有效降低总成本,或者将车辆数作为能力约束,造成企业各计划期内需求变化较大时不便于合理设置车辆数等问题,提出一个需求可拆分、动态车辆数的多周期订货—运输集成优化模型。鉴于目前该问题缺乏有效的求解算法,提出一种遗传算法与2-OPT算法相结合的混合遗传算法,针对问题的特点设计了一种二维编码方式来处理多周期订货时间和数量问题,并通过算例验证了模型和算法的有效性。 展开更多
关键词 周期订货—运输集成问题 需求拆分 动态车辆数 混合遗传算法
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农村垃圾中转站到处理厂的周期性运输方案研究 被引量:1
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作者 季飞 连淑君 《运筹与模糊学》 2014年第3期35-41,共7页
本文针对农村垃圾中转站到处理厂的运输进行研究。根据实际情况,提出了两个周期性运输方案:周期运输,即先将垃圾在中转站内进行存储,然后中转站按各自周期将垃圾清运到处理厂;每日运输,有余量的周期性运输,即每天将垃圾运往处理厂,但由... 本文针对农村垃圾中转站到处理厂的运输进行研究。根据实际情况,提出了两个周期性运输方案:周期运输,即先将垃圾在中转站内进行存储,然后中转站按各自周期将垃圾清运到处理厂;每日运输,有余量的周期性运输,即每天将垃圾运往处理厂,但由于车辆不满载造成垃圾剩余,周期性清运剩余垃圾。通过对运输方案建立费用最小数学模型,从而得出各垃圾中转站的最优中转周期。最后通过具体的案例,证明了方案的有效性。文章模型科学,数据分析合理,分析了农村垃圾的处理方案的优化问题,有一定的参考价值。 展开更多
关键词 垃圾中转站 处理厂 周期运输
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紧急事件医疗物资多层级、多周期运输供应探讨
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作者 李天骥 《中阿科技论坛(中英文)》 2020年第9期192-198,共7页
传统运输问题的目标是使运输总费用尽量少,而本文的主要目标是先满足医疗物资的需求,再考虑运输费用的问题。这个模型非常重要的应用就是当紧急事件发生时,如新冠疫情,如何有效地将医疗物资送往各个医疗单位,从而尽可能地保障人们的生... 传统运输问题的目标是使运输总费用尽量少,而本文的主要目标是先满足医疗物资的需求,再考虑运输费用的问题。这个模型非常重要的应用就是当紧急事件发生时,如新冠疫情,如何有效地将医疗物资送往各个医疗单位,从而尽可能地保障人们的生命安全,同时在医疗物资最大限度送达的条件下尽可能地节约费用。本文将建立一个紧急事件发生下的多层级、多周期运输模型,给出一个相应有效的算法,并通过计算机模拟实例证明模型与算法的有效性。 展开更多
关键词 医疗物资供应 运输模型 多层级多周期运输
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长距离管线施工中管道运输的问题及解决方法 被引量:1
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作者 孙显峰 段少杰 马宇 《水利建设与管理》 2010年第6期28-29,共2页
在大伙房水库输水(二期)工程中,管线施工是制约整体施工进度的主要因素,而管线施工进度又受到管道运输的制约。管道运输又可以分为管道装卸、运输车辆、运输道路和运输周期四大环节。
关键词 管道装卸 运输车辆 运输道路 运输周期
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哈密露天矿实施空车大坡道优化运输系统
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作者 向朝阳 赵春晨 《露天采矿技术》 CAS 2006年第4期22-23,共2页
哈密煤业集团露采公司通过实施空车大坡道技术改造优化了运输系统,缩短了列车的运输距离,减少了运行周期,提高了运输效率,获得了良好的经济效益。
关键词 大坡道 运距 运输周期 效率
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实行甩挂运输 提高运输效率
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作者 吴润元 《交通与运输》 1999年第3期18-19,共2页
随着城乡经济的繁荣和高速公路的涌现,汽车长途货运日益发展。目前上海已开通至全国各地的货运班线118条,基本已形成以上海为中心、辐射华东、开通全国的网络。上海的货物可以直达或中转至全国28个省市1180个县市。货车线路也由短变长,... 随着城乡经济的繁荣和高速公路的涌现,汽车长途货运日益发展。目前上海已开通至全国各地的货运班线118条,基本已形成以上海为中心、辐射华东、开通全国的网络。上海的货物可以直达或中转至全国28个省市1180个县市。货车线路也由短变长,上海至北京、哈尔滨、广州、深圳、成都、西安的线路均在1000公里以上,总通车里程已达93094公里。 由于货车运距的伸展,运输周期的延长。 展开更多
关键词 甩挂运输 运输效率 驮背运输 运输方式 高速公路 牵引车 货运站 滚装运输 运输周期 城乡经济
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关于铁路运输装备全生命周期成本智能管控的探讨
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作者 冯卓豫 郭燕 叶润枝 《财务与会计》 北大核心 2023年第6期25-28,共4页
针对铁路企业运输装备成本管理中存在的一系列问题,本文结合全生命周期成本管理模式,提出通过完善管理制度、构建全面成本管理模块及构建成本分析导图,合理控制采购规模,提高物资使用效率,减少积压,充分发挥出成本控制优势。
关键词 铁路运输装备全生命周期 智能管控平台 成本管理
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我国农村生鲜产品电商水平指标评价及发展策略 被引量:1
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作者 王悦 《内蒙古财经大学学报》 2021年第5期131-135,共5页
农村电商的快速发展,大大改善了农村生鲜产品的经济效益。由于农户在电子商务平台的选择上具有非一致性,考察农户视角下的电子商务水平,将有助于判断电子商务平台发展方向。基于此,文章研究并量化了生鲜产品电子商务销售的三大主流平台... 农村电商的快速发展,大大改善了农村生鲜产品的经济效益。由于农户在电子商务平台的选择上具有非一致性,考察农户视角下的电子商务水平,将有助于判断电子商务平台发展方向。基于此,文章研究并量化了生鲜产品电子商务销售的三大主流平台,构建了影响电子商务生鲜品类发展水平的指标。研究结果显示,影响生鲜电子商务发展水平的核心公因子分别是生鲜产品运输周期和信息透明度,生鲜运营能力由高到低排序分别为淘宝、京东、拼多多。通过此研究得出为保持更短的生鲜产品运输周期,需要尽可能提高平台信息透明度,以期有效增强生鲜电子商务平台运营能力。 展开更多
关键词 生鲜产品 运输周期 信息透明度 电子商务 运营指标 结构指标
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长距离大直径盾构隧道洞内单车道段车辆调度模型研究 被引量:8
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作者 梁峻海 张晓平 +5 位作者 谢维强 吴坚 陈鹏 孙茂舟 钱玉华 黄云天 《隧道建设(中英文)》 北大核心 2018年第A02期209-217,共9页
为研究盾构隧道洞内无轨运输具体的车辆调度方案,依托苏通GIL综合管廊工程(工程采用预制中间箱涵、现浇两侧箱涵的方式建成双层结构),根据本工程物料运输的特点,以重要物料优先考虑、减少车辆等待时间为原则,提出单车道段车辆调度方案,... 为研究盾构隧道洞内无轨运输具体的车辆调度方案,依托苏通GIL综合管廊工程(工程采用预制中间箱涵、现浇两侧箱涵的方式建成双层结构),根据本工程物料运输的特点,以重要物料优先考虑、减少车辆等待时间为原则,提出单车道段车辆调度方案,并针对方案中各车辆行驶和卸料用时之间的关系,建立运输车辆调度数学模型,对该车辆调度方案的可行性进行论证分析。通过模型分析可得出结论:该车辆调度方案能满足工程中物料供应的要求,单环运输周期和单车道长度呈线性关系。并得出本工程设定工况下的运输间歇为0.48 h,最小掘进周期为1.52 h,单车道极限长度为1.16 km,掘进速度最大可提升32%。 展开更多
关键词 长大隧道 无轨运输 车辆调度模型 运输周期
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海底隧道穿越渤海海峡
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《矿产勘查》 2003年第5期3-12,共2页
关键词 海底隧道 渤海海峡 火车轮渡 运输方式 通过能力 运输周期 发展趋势 《中国国家地理》 通道工程 地下工程
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Effects of Mechanical Impacts on Hatchability of Broiler Breeders
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作者 Timea Torma Katalin Gafil Kovhcsn 《Journal of Agricultural Science and Technology(A)》 2014年第6期535-540,共6页
Transporting hatching eggs from Hungary and incubating them abroad revealed lower hatchability compared to when the eggs were incubated in Hungary. Following transport, there were higher embryo losses and, notably, mo... Transporting hatching eggs from Hungary and incubating them abroad revealed lower hatchability compared to when the eggs were incubated in Hungary. Following transport, there were higher embryo losses and, notably, more malformed embryos. The aim of these initial trials was to determine if a testing device (crazy fit massage machine (CFM machine)) was able to replicate and model the mechanical impacts experienced during transport and reproduce the reduction in hatchability and increase the level of malformed embryos as observed in commercial practice. Tinytag~ high sensitivity shock and vibration loggers were used to monitor the impacts under field and trial conditions. Applying single 10 min treatments on the CFM machine, which used the same frequency (10-30 Hz) as the eggs experience under field conditions, induced the negative effect of transport, and lower hatching results were experienced. Three trials were conducted. Treated eggs in Trials 1 and 2 received automatically and periodical changing vibration in a range between 10-30 Hz for 10 min while in Trial 3 two different levels of impact were applied at 20 Hz and 30 Hz, respectively. Hatchability decreased due to the treatment significatly only in Trial 3. Significant differences were also detected in early dead levels in Trials 2 and 3 and the occurrences of malformation in Trials 1 and 3. All these results are in accordance with the field experience. Thus, the trials which examined the equipment were able to produce mechanical impacts that were repeatable in order to set up statistically reliable trials on hatching eggs. 展开更多
关键词 Mechanical impacts HATCHABILITY loggers.
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A comparison of the energy consumption and carbon emissions for different modes of transportation in open-cut coal mines 被引量:13
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作者 Liu Fuming Cai Qingxiang +1 位作者 Chen Shuzhao Zhou Wei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第2期261-266,共6页
Transportation accounts for 80% of open-cut coal mine carbon emissions. With regard to the energy con- sumption and carbon emissions of transportation within an open-cut mine, this paper systematically compared the wo... Transportation accounts for 80% of open-cut coal mine carbon emissions. With regard to the energy con- sumption and carbon emissions of transportation within an open-cut mine, this paper systematically compared the work and energy consumption of a truck and belt conveyor on a theoretical basis, and con- structed a model to calculate the energy consumption of open-cut mine transportation. Life cycle carbon emission factors and power consumption calculation model were established through a Process Analysis- Life Cycle Analysis (PA-LCA). The following results were obtained: (1) the energy consumption of truck transportation was four to twelve times higher than that of the belt conveyor; (2) the C02 emissions from truck transportation were three to ten times higher than those of the belt conveyor; (3) with the increase in the slope angle for transportation, the ratio of truck to belt conveyor for both energy consumption and carbon emissions gradually decreased; (4) based on 2013 prices in China, the energy cost of transportation using a belt conveyor in open-cut coal mines could save 0.6-2.4 Yuan/(t kin) compared to truck transportation. 展开更多
关键词 Open-cut coal mine Mode of transportation Energy efficiency Carbon emission calculation
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GENERAL SITUATION ABOUT ACTIVITY OF SUMMER MONSOON OVER SOUTH CHINA SEA IN 2004 ASIAN SUMMER MONSOON INDEX
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作者 李春晖 梁建茵 《Journal of Tropical Meteorology》 SCIE 2006年第2期105-112,共8页
Based on daily NCEP reanalysis data, OLR and satellite rainfall data, the characteristic of theactivities of South China Sea summer monsoon(SCSSM) in 2004 were analyzed. The results showed that theestablishment of SCS... Based on daily NCEP reanalysis data, OLR and satellite rainfall data, the characteristic of theactivities of South China Sea summer monsoon(SCSSM) in 2004 were analyzed. The results showed that theestablishment of SCSSM was little later than normal and the intensity was stronger than normal. Influenced bythe location of the northwest Pacific subtropical high, which was much northward and westward than normal,SCSSM was active mainly in the South China Sea areas. There existed obvious intraseasonal oscillation and twosignificant periods of SCSSM, one was about 20-30 days and the other about 40-50 days. The transportation ofmoisture was concentrated on the South China Sea and the northwest Pacific regions, reducing the northwardtransportation and resulting in drought in southern China. 展开更多
关键词 South China Sea summer monsoon ONSET intraseasonal oscillation moisture transport
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Electron Transport in Graphene-Based Double-Barrier Structure under a Time Periodic Field
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作者 卢伟涛 王顺金 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期163-167,共5页
The transport property of electron through graphene-based double-barrier under a time periodic field is investigated. We study the influence of the system parameters and external field strength on the transmission pro... The transport property of electron through graphene-based double-barrier under a time periodic field is investigated. We study the influence of the system parameters and external field strength on the transmission probability. The results show that transmission exhibits various kinds of behavior with the change of parameters due to its angular anisotropy. One could control the values of transmission and conductivity as well as their distribution in each band by tuning the parameters. 展开更多
关键词 graphene-based double-barrier structure Klein tunneling external field
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化工物流的成功之路
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作者 汪涵 曹炳武 《中国石油企业》 2005年第7期54-55,共2页
一体化物流管理体系运转一年多来,信息反馈及时,运行效率高,实现了缩短运输周期、压缩运输费用、方便客户的目标。
关键词 化工物流 运输周期 中国 石油化工 物流管理
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Quantum Transport through a Rigidly Connected Double Quantum-Dot Shuttle
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作者 江兆潭 黎莎 +1 位作者 吕增涛 张国锋 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第4期536-544,共9页
We design a double quantum-dot (QD) shuttle (DQDS) model including two rigidly connected QDs that are softly linked to two leads via deformable organic materiaJs. Based on the full quantum mechanical approaches we... We design a double quantum-dot (QD) shuttle (DQDS) model including two rigidly connected QDs that are softly linked to two leads via deformable organic materiaJs. Based on the full quantum mechanical approaches we explore the influences on the electron transport induced by the electrical and mechanical degrees of freedom. First of a/l the modified rate equations of the DQDS are derived theoretically and then a numerical investigation on the quantum transport through the DQDS is performed. For the classical DQDS, the time-dependent evolutions of the electron- occupation probabilities and the currents flowing through the DQDS show the periodic oscillations with their periods determined by the oscillation period of the DQDS. Both the mechanical oscillation amplitude and the interdot coupling can play crucial roles in adjusting the peak shapes of the currents and the probabilities. For the quantum DQDS, the current and electron-occupation probabilities of the DQDS evolve into a stationary state as time goes on, with no periodical oscillations observed. As a consequence, the sharp differences of the time-dependent properties between the c/assica/ and quantum DQDS systems are clearly demonstrated, which should be greatly helpful in designing new nanoelectromechanical devices. Also, this work is of great significance to understanding the kind of rigidly connected QD shuttle systems that have more than two QDs. 展开更多
关键词 nanoelectromechanical systems quantum dots single-electron tunneling
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