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外科模板结合Pick-up技术在无牙颌即刻负重种植修复中的临床应用 被引量:7
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作者 耿威 马攀 +2 位作者 李钧 刘长营 谭包生 《口腔颌面修复学杂志》 2015年第4期212-217,共6页
目的:探讨应用种植外科模板结合Pick-up技术进行无牙颌即刻负重种植修复,评估应用Pick-up技术使预先制作的修复体即刻负重的可行性及临床效果。方法:9例无牙颌患者采用带有预成修复体信息的种植外科模板引导种植体植入,而后应用预成的... 目的:探讨应用种植外科模板结合Pick-up技术进行无牙颌即刻负重种植修复,评估应用Pick-up技术使预先制作的修复体即刻负重的可行性及临床效果。方法:9例无牙颌患者采用带有预成修复体信息的种植外科模板引导种植体植入,而后应用预成的修复体结合Pick-up技术制作种植体支持的临时修复体,完成无牙颌即刻负重修复。随访临时修复体功能状况,总结Pick-up技术的就诊次数、被动就位情况、颌位关系、患者满意度。6个月后进行永久修复,定期随访观察种植体存留情况,种植体周围边缘骨吸收情况和种植体支持的修复体应用状况。结果:9例患者共植入56枚种植体,1颗种植体脱落,53颗种植体即刻负重,完成下颌6个、上颌3个种植体支持的树脂材料临时修复体。随访时间12-60个月(平均36个月),全部即刻负重的种植体稳定无松动,种植体边缘骨吸收0.5±0.24m m,即刻负重种植体存留率100%。全部种植体存留率98.2%,全部永久修复体均正常行使功能。利用种植外科模板通过Pick-up技术进行即刻负重修复治疗时间短,就诊次数少,一次获得被动就位,颌位关系准确,患者满意度高。结论:种植外科模板结合Pick-up技术进行种植体的即刻负重修复,可实现微创准确快速的种植治疗,临床效果满意。 展开更多
关键词 牙种植 牙列缺失 即刻负重 外科模板 pick-up技术
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数字化导板与pick-up技术在牙列缺失种植修复中的应用1例 被引量:3
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作者 张凯悦 赵保东 +1 位作者 韩泽禹 滕敏华 《中华老年口腔医学杂志》 2022年第6期348-352,共5页
随着经济及医学水平的高速发展,我国老年无牙颌患者呈逐年上升趋势。常规全口义齿修复存在诸多缺点,不能满足于老年无牙颌患者的生活需求[1]。种植体支持的固定全口义齿修复被证明是恢复无牙颌患者面部美学及功能、提高患者生活质量的... 随着经济及医学水平的高速发展,我国老年无牙颌患者呈逐年上升趋势。常规全口义齿修复存在诸多缺点,不能满足于老年无牙颌患者的生活需求[1]。种植体支持的固定全口义齿修复被证明是恢复无牙颌患者面部美学及功能、提高患者生活质量的有效治疗手段[2]。而数字化导板可帮助引导种植体精确就位,防止损伤邻近软硬组织等重要的解剖结构,确保种植体达到设计的位置、深度及角度,更有助于符合生物学为导向的种植治疗理念[3-4]。而即刻修复缩短了空牙期,满足了患者即刻恢复美观的需求。 展开更多
关键词 种植牙 牙列缺失 数字化导板 计算机辅助外科 pick-up技术 种植即刻负重
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Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission 被引量:11
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作者 Yaxin Yu Jikun Liu +4 位作者 Bingliang Ye Gaohong Yu Xuejun Jin Liang Sun Junhua Tong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期42-54,共13页
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ... Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. 展开更多
关键词 Dryland plug SEEDLING transplanter Rotary SEEDLING pick-up MECHANISM TRANSMISSION ratio Non-uniform continuous TRANSMISSION COMBINED NON-CIRCULAR gear TRANSMISSION Optimization design
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Astronomical Tables in the“Lü-li zhi”:On the Characteristics and Adoption of“Licheng”Pick-up Tables 被引量:2
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作者 Li Liang 《Chinese Annals of History of Science and Technology》 2018年第2期41-71,共31页
This article discusses the development of astronomical tables in ancient China based on the calendrical chapter titled“Lü-li zhi”律曆志(Monograph on harmonics and calendrical astronomy)in official histories.Aft... This article discusses the development of astronomical tables in ancient China based on the calendrical chapter titled“Lü-li zhi”律曆志(Monograph on harmonics and calendrical astronomy)in official histories.After surveying various types of astral scientific tables in ancient China and their layouts,this paper discusses the characteristics and adoption of“licheng”立成tables,a specific kind of pick-up table that seems to have come into use in the Sui period(581–618)and to have been widespread from the Tang period(618–907)onward.The emergence of licheng tables relates largely to the internal development of ancient Chinese astronomy,but they were also probably inspired by auspicial tables and foreign astronomical tables.By comparing tables recorded in the“Lü-li zhi”and the existing licheng tables,we find that most licheng were deleted during the compilation of“Lü-li zhi”to reduce the number of volumes.Moreover,this paper discusses several common solutions used to compress the size of tables in“Lü-li zhi.”The adoption of licheng tables into the ancient Chinese astral sciences and the reformatting of them in“Lü-li zhi”give us a different perspective for understanding the development of ancient Chinese astronomical tables and the compilation of the calendrical portion of official histories. 展开更多
关键词 “Lü-li zhi” pick-up table“licheng” astronomical tables
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Cause analysis of and solution to furnace roller pick-up in the high strength automotive steel sheet processing line
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作者 WANG Lu 《Baosteel Technical Research》 CAS 2013年第2期44-48,共5页
Cold-rolled high strength steel sheets for automobiles contain more Mn and Si based alloy elements, which, under the reducing atmosphere in the annealing furnace, will get enriched on the strip surface. Since the furn... Cold-rolled high strength steel sheets for automobiles contain more Mn and Si based alloy elements, which, under the reducing atmosphere in the annealing furnace, will get enriched on the strip surface. Since the furnace rollers and the strips contact frequently, alloy elements on the roller surface will form hard protuberance. We call this protuberance "pick-up". In addition, with the increase of the amount of dust in the furnace atmosphere, the occurrence of furnace roller pick-up will also increase. Through chemical reaction and physical accumulation analysis combined with practical experience, the causes of pick-up in different furnace sections were analyzed. Methods of preventing furnace roller pick-up in the high strength steel sheet processing line were discussed and solutions to improving the strip surface quality in the continous annealing furnace were provided. 展开更多
关键词 high strength steel continuous annealing furnace roller pick-up furnace atmosphere cleanliness
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A STUDY OF WAVELET ENTROPY MEASURE DEFINITION AND ITS APPLICATION FOR FAULT FEATURE PICK-UP AND CLASSIFICATION
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作者 He Zhengyou Chen Xiaoqin Qian Qingquan 《Journal of Electronics(China)》 2007年第5期628-634,共7页
Shannon entropy in time domain is a measure of signal or system uncertainty.When based on spectrum entropy,Shannon entropy can be taken as a measure of signal or system complexity. Therefore,wavelet analysis based on ... Shannon entropy in time domain is a measure of signal or system uncertainty.When based on spectrum entropy,Shannon entropy can be taken as a measure of signal or system complexity. Therefore,wavelet analysis based on wavelet entropy measure can signify the complexity of non-steady signal or system in both time and frequency domain.In this paper,in order to meet the requirements of post-analysis on abundant wavelet transform result data and the need of information mergence,the basic definition of wavelet entropy measure is proposed,corresponding algorithms of several wavelet entropies,such as wavelet average entropy,wavelet time-frequency entropy,wavelet distance entropy, etc.are put forward,and the physical meanings of these entropies are analyzed as well.The application principle of wavelet entropy measure in ElectroEncephaloGraphy (EEG) signal analysis,mechanical fault diagnosis,fault detection and classification in power system are analyzed.Finally,take the transmission line fault detection in power system for example,simulations in two different systems,a 10kV automatic blocking and continuous power transmission line and a 500kV Extra High Voltage (EHV) transmission line,are carried out,and the two methods,wavelet entropy and wavelet modulus maxima,are compared,the results show feasibility and application prospect of the six wavelet entro- pies. 展开更多
关键词 Shannon entropy Wavelet analysis Wavelet entropy Feature pick-up Power systems
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关于pick-up的常见问题
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作者 魏国 《乐器》 2003年第7期74-75,共2页
电吉他pick-up的发明是为了使吉他发出更大的声音,也因此有了所谓"电"吉他.我们可以视之为一种能量的转换装置,对音色有很大影响.早期研究发展pick-up多在Fender、Gibson为主的大公司内进行,不同于今日百家争鸣的局面.
关键词 电吉他 pick-up 音色 拾音器 线圈 缠绕方法
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Improvement of Pick-up Mechanism for Composite Particle Emissions
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《Chinese journal of nuclear physics》 1996年第1期29-33,共5页
ImprovementofPick┐upMechanismforCompositeParticleEmisionsZhangJingshangandZhouSuijianChinaInstituteofAtomicE... ImprovementofPick┐upMechanismforCompositeParticleEmisionsZhangJingshangandZhouSuijianChinaInstituteofAtomicEnergy,P.O.Box275(... 展开更多
关键词 pick-up COMPOSITE EMISSIONS IMPROVEMENT MECHANISM
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Reverse design and tests of vegetable plug seedling pick-up mechanism of planetary gear train with non-circular gears 被引量:3
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作者 Zhifang Zhu Guohuan Wu +1 位作者 Bingliang Ye Yongchang Zhang 《International Journal of Agricultural and Biological Engineering》 SCIE 2023年第2期96-102,共7页
In the previous research,the seedling pick-up mechanism of the planetary gear train with incomplete eccentric circular gear and non-circular gears for vegetable plug seedlings still has two shortcomings.One is that no... In the previous research,the seedling pick-up mechanism of the planetary gear train with incomplete eccentric circular gear and non-circular gears for vegetable plug seedlings still has two shortcomings.One is that not enough seedling pick-up depth leads to a low success ratio of seedling pick-up at high rotation speeds,the other is that the smaller seedling pushing angle results in poor seedling pushing effect.Therefore,the reverse design of the seedling pick-up mechanism based on its motion trajectory was carried out.The local trajectory of seedling pick-up and seedling pushing sections was adjusted to obtain the theoretical motion trajectory of the seedling pick-up mechanism.The cubic non-uniform B-spline curve was used to fit the adjusted trajectory.A novel seedling pick-up mechanism of the planetary gear train with non-circular gears was proposed,including three combined non-circular gears,four non-circular gears,one planetary carrier,and two seedling pick-up arms.The reverse design model of the mechanism was established.The analysis and design software of the mechanism was developed to obtain the mechanism parameters meeting design requirements.The virtual prototype of the mechanism was established and its physical prototype was manufactured.Through the virtual motion simulation and high-speed photographic kinematics bench tests of the mechanism,the kinematic model and results of reverse design of the mechanism were verified,with the kinematic performances of the mechanism prototype studied.The seedling pick-up tests of the mechanism were conducted in the laboratory.The success ratios of seedling pick-up were 94.2%,95.6% and 90.2% while the seedling pick-up efficiencies of the mechanism were 60,80 and 100 plants per minute per row,respectively.Besides,the seedling pushing effect was improved mush because of the greater seedling pushing angle.The seedling pick-up mechanism through revise design is of high value to be applied in the practical vegetable plug seedling transplanters. 展开更多
关键词 vegetable plug seedling seedling pick-up mechanism non-circular gear reverse design virtual simulation seedling pick-up tests
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Design and tests of a rotary plug seedling pick-up mechanism for vegetable automatic transplanter 被引量:6
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作者 Bingliang Ye Gongjun Zeng +3 位作者 Bin Deng Chiulan Yang Jikun Liu Gaohong Yu 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2020年第3期70-78,共9页
The rotary plug seedling pick-up mechanism for vegetable automatic transplanter is the technical bottleneck to improve the mechanization level of vegetable planting in China.In order to solve the problems of rotary se... The rotary plug seedling pick-up mechanism for vegetable automatic transplanter is the technical bottleneck to improve the mechanization level of vegetable planting in China.In order to solve the problems of rotary seedling pick-up mechanism proposed in previous study,such as low success ratio of seedling pick-up at high speed,and interference between the seedling bowl and the end of the other seedling pick-up arm,a novel kind of rotary seedling pick-up mechanism of planetary gear train with combined type gears of incomplete denatured-eccentric-circular and non-circular gears was proposed.Through kinematic analysis of the seedling pick-up mechanism,the kinematics model was established.The computer-aided analysis and optimization software with human-computer interaction method was developed to realize parameters optimization of the seedling pick-up mechanism.Three-dimensional parametric design system of seedling pick-up mechanisms with combined non-circular gear transmission was developed for mechanism virtual simulation to verify the correctness of theoretical model and design results of the mechanism.The physical prototype of the mechanism was manufactured,and high-speed camera kinematics tests of the mechanism were conducted in the laboratory to study its kinematic characteristics.Laboratory seedling pick-up tests were carried out.The mechanism has the success ratio of seedling pick-up 96.3%without interference during seedling transporting when the rotation speed of the mechanism is 50 r/min and the seedling transplanting efficiency is 100 plants/min per row,showing that the novel mechanism has better working performance than the original one and could be applied in vegetable plug seedling transplanter. 展开更多
关键词 vegetable automatic transplanter rotary seedling pick-up mechanism incomplete denatured-eccentric-circular gear kinematic analysis parametric design
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Influence of reaction of Al2O3 and carbonaceous materials in Al2O3–C refractories on aluminum and carbon pick-up of iron 被引量:2
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作者 Yao-wu Wei Yan-jun Dong +2 位作者 Tao Zhang Jun-feng Chen Wen Yan 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2020年第1期55-61,共7页
Carbon-containing Al2O3 refractory crucibles and pure Al2O3 refractory crucible were fabricated to study the effect of carbon-containing Al2O3-C refractories on aluminum and carbon pick-up of iron.Refractory crucibles... Carbon-containing Al2O3 refractory crucibles and pure Al2O3 refractory crucible were fabricated to study the effect of carbon-containing Al2O3-C refractories on aluminum and carbon pick-up of iron.Refractory crucibles with pure iron powder were placed in a vacuum induction furnace and heated at 1600℃ for regular time under flowing argon atmosphere.The Al and C contents of iron samples were analyzed,and iron samples were also investigated using a field scanning electron microscope equipped with energy-dispersive spectroscope.The results showed that carbon materials did affect the interac?tion of(Al2O3-C)/Fe system,carbothermal reduction in alumina occurred in the reaction system and the extent of reactions depended on the kinds of carbon materials. 展开更多
关键词 AL2O3-C refractory Liquid IRON ALUMINUM pick-up Carbon pick-up Carbothermal reduction
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A tripartite evolutionary game analysis of providing subsidies for pick-up/drop-off strategy in carpooling problem
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作者 Zeyuan Yan Li Li +2 位作者 Hui Zhao Yazan Mualla Ansar Yasar 《Autonomous Intelligent Systems》 EI 2023年第1期50-65,共16页
Although the pick-up/drop-off(PUDO)strategy in carpooling offers the convenience of short-distance walking for passengers during boarding and disembarking,there is a noticeable hesitancy among commuters to adopt this ... Although the pick-up/drop-off(PUDO)strategy in carpooling offers the convenience of short-distance walking for passengers during boarding and disembarking,there is a noticeable hesitancy among commuters to adopt this travel method,despite its numerous benefits.Here,this paper establishes a tripartite evolutionary game theory(EGT)model to verify the evolutionary stability of choosing the PUDO strategy of drivers and passengers and offering subsidies strategy of carpooling platforms in carpooling system.The model presented in this paper serves as a valuable tool for assessing the dissemination and implementation of PUDO strategy and offering subsidies strategy in carpooling applications.Subsequently,an empirical analysis is conducted to examine and compare the sensitivity of the parameters across various scenarios.The findings suggest that:firstly,providing subsidies to passengers and drivers,along with deductions for drivers through carpooling platforms,is an effective way to promote wider adoption of the PUDO strategy.Then,the decision-making process is divided into three stages:initial stage,middle stage,and mature stage.PUDO strategy progresses from initial rejection to widespread acceptance among drivers in the middle stage and,in the mature stage,both passengers and drivers tend to adopt it under carpooling platform subsidies;the factors influencing the costs of waiting and walking times,as well as the subsidies granted to passengers,are essential determinants that require careful consideration by passengers,drivers,and carpooling platforms when choosing the PUDO strategy.Our work provides valuable insight into the PUDO strategy’s applicability and the declared results provide implications for traffic managers and carpooling platforms to offer a suitable incentive. 展开更多
关键词 Carpooling problem pick-up/drop-off strategy Offering subsidies strategy Tripartite evolutionary game theory Evolutionarily stable strategy
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学生通学出行的家长接送方式的选择 被引量:3
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作者 马书红 邵恒 陈西芳 《深圳大学学报(理工版)》 CAS CSCD 北大核心 2024年第2期213-220,共8页
研究家长接送方式选择的影响因素,对于早晚高峰交通出行政策的制定具有重要意义.考虑家长、学生的个人属性与家庭属性,以及后续行程目的、生理成本与延误时间等出行属性因素,基于多项logit(multinomial logit,MNL)模型分析对于家长接送... 研究家长接送方式选择的影响因素,对于早晚高峰交通出行政策的制定具有重要意义.考虑家长、学生的个人属性与家庭属性,以及后续行程目的、生理成本与延误时间等出行属性因素,基于多项logit(multinomial logit,MNL)模型分析对于家长接送学生交通方式选择的影响因素,并通过中国海宁市居民出行数据进行验证.研究结果表明,家长年龄越大,选择步行接送的可能性越大;学生性别对于家长接送方式的选择没有显著影响;家长性别和学生年龄对接送方式具有显著影响,其中,女性接送者更偏向于选择非机动车接送,学生年龄越小,家长更偏向于选择非机动车接送;后续行程目的为上班的家长更偏向于选择机动车接送;小汽车接送者的接送时间相对较长,但该接送方式承担的生理成本和延误时间相对较少;电动车接送者承担的生理成本和时间成本都较低.依据研究结果,从家庭、学校和交通管制等维度对学生通学出行提出相关改善建议,能够为相关部门从学生通学的角度制定交通规划管理政策、方案提供指导. 展开更多
关键词 交通工程 通学出行 家长接送 多项logit模型 影响因素 方式选择
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可调倾角编程式多功能取苗试验台设计与试验
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作者 尹大庆 刘港 +1 位作者 张明鑫 王金武 《农业机械学报》 EI CAS CSCD 北大核心 2024年第6期143-149,共7页
针对现有取苗试验台不能满足多种型号钵盘和取苗机构进行取苗试验的需求,设计了一种由多个步进电机驱动、可调取苗机构倾角、可编程控制系统的多功能取苗试验台。该试验台通过调节取苗机构安装支架的位姿、改变钵盘驱动鼠笼钢丝间距以... 针对现有取苗试验台不能满足多种型号钵盘和取苗机构进行取苗试验的需求,设计了一种由多个步进电机驱动、可调取苗机构倾角、可编程控制系统的多功能取苗试验台。该试验台通过调节取苗机构安装支架的位姿、改变钵盘驱动鼠笼钢丝间距以及所在圆周直径,可以适应不同型号钵盘和满足多种取苗机构的试验要求;通过编写控制器程序可控制3个步进电机联动并实现送苗装置的横、纵向送苗与取苗机构取苗进程相匹配。在三维软件中对试验台进行了建模、装配和虚拟仿真,在加工制造的物理样机上进行了2种型号钵盘和3种取苗机构的取苗试验。3次试验结果表明:在此试验台上能够顺利完成取苗试验,证明该试验台满足多种型号钵盘和多种类型取苗机构的试验需求。 展开更多
关键词 钵苗移栽 试验台 横向送苗 取苗机构 编程控制
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考虑客户满意度的实时取送货路径优化问题
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作者 吴腾宇 张景露 余海燕 《运筹与管理》 CSSCI CSCD 北大核心 2024年第4期21-27,I0002,共8页
针对即时配送订单出现的动态性、服务客户的满意度、末端配送路网的非对称性,在配送订单的时间窗限制下,建立实时取送货路径优化模型。通过定义并调整非对称网络系数,构建非对称配送网络,提出滚动时域忽略策略(Ignore策略)和滚动时域实... 针对即时配送订单出现的动态性、服务客户的满意度、末端配送路网的非对称性,在配送订单的时间窗限制下,建立实时取送货路径优化模型。通过定义并调整非对称网络系数,构建非对称配送网络,提出滚动时域忽略策略(Ignore策略)和滚动时域实时判断策略(Real-time策略)。Ignore策略要求配送员一旦出发,返回配送起点前忽略所有新出现的订单,Real-time策略要求配送途中实时判断当新订单出现时,是否返回起点取货,重新规划配送路线。使用数值仿真软件,在不同非对称系数、客户时间窗、订单数量等的情形下分析策略适用性。数值算例分析表明,Real-time策略适用于网络较大的情形,而网络较小且订单数量较少时,Ignore策略更适用。研究结果可为城市末端合单配送和路径优化策略提供新的思路和参考。 展开更多
关键词 旅行商问题 合单配送 实时取送货 单边软时间窗 非对称网络
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模糊时间窗下的车机并行取送货问题研究
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作者 李四兰 李佳 《物流科技》 2024年第14期85-91,共7页
为解决农村“最后一公里”的取送货以及客户满意度低的难题,文章提出卡车搭配无人机配送的模式,以配送总成本最小化和客户满意度最大化为目标建立数学约束模型,采用改进的遗传算法求解,并以江西省赣州市定南县的村庄为例进行应用研究,... 为解决农村“最后一公里”的取送货以及客户满意度低的难题,文章提出卡车搭配无人机配送的模式,以配送总成本最小化和客户满意度最大化为目标建立数学约束模型,采用改进的遗传算法求解,并以江西省赣州市定南县的村庄为例进行应用研究,结果表明卡车搭配无人机并行的运输模式与单独使用卡车的运输方式相比,总成本得到充分降低,客户满意度也显著提高。因此文章研究成果有望为解决农村“最后一公里”配送降本增效以及提高客户满意度提供新思路和参考价值。 展开更多
关键词 模糊时间窗 无人机 取送货 物流路径规划
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多能源混合车队生鲜品配送车辆路径问题研究
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作者 周晓晔 戴思聪 《沈阳工业大学学报(社会科学版)》 2024年第3期301-310,共10页
针对同时考虑取送货和分时电价的电动车与燃油车混合车队车辆路径问题,以车辆固定成本、行驶成本、制冷成本、货损成本、时间窗成本、碳排放成本和充电成本之和最小为目标,构建生鲜品配送车辆路径优化模型,设计融合邻域搜索的遗传模拟... 针对同时考虑取送货和分时电价的电动车与燃油车混合车队车辆路径问题,以车辆固定成本、行驶成本、制冷成本、货损成本、时间窗成本、碳排放成本和充电成本之和最小为目标,构建生鲜品配送车辆路径优化模型,设计融合邻域搜索的遗传模拟退火混合算法并求解。结果表明:相比于取送分离,同时取送货模式能够显著提升配送效率,提高车辆装载率;通过技术升级适当增加电动车的电池容量,能够弱化车辆路径方案对充电设施的依赖程度,有效降低配送成本;通过与遗传算法、遗传变邻域混合算法运行结果对比,验证本文算法的有效性,为冷链物流企业在配送环节实现节能减排、降本增效提供借鉴和参考。 展开更多
关键词 混合车队 遗传模拟退火混合算法 冷链物流 电动车配送 取送货 分时电价
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结合载客热点和POI的出租车停车位划定方法
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作者 邢雪 王菲 李佳楠 《吉林大学学报(信息科学版)》 CAS 2024年第1期93-99,共7页
针对出租车随意停靠造成城市交通拥堵甚至交通事故的问题,利用成都实际区域的出租车GPS(Global Position System)数据和爬取的POI(Point of Interest)数据,使用DBSCAN(Density-Based Spatial Clustering of Application with Noise)聚... 针对出租车随意停靠造成城市交通拥堵甚至交通事故的问题,利用成都实际区域的出租车GPS(Global Position System)数据和爬取的POI(Point of Interest)数据,使用DBSCAN(Density-Based Spatial Clustering of Application with Noise)聚类算法对上下客点进行聚类,得到出租车的载客热点,根据POI的类型划定载客热点区域的类型,对出租车不同时间的出行需求进行分析,进而划分出出租车的固定停车区域。研究结果表明,出租车固定停车区域的设定与出行者的出行需求有关,即将固定停车区域设置在出行者出行需求多的区域,可以满足出行者的不同出行需求。结合出租车载客热点和爬取POI数据划定固定停车区域的方法具有较高的实用性,可为城市交通安全方面提供理论和现实意义。 展开更多
关键词 上下客点 DBSCAN聚类算法 载客热点区域 POI数据分析 固定停车区域
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Basic Research on the Burden of Dropping off and Picking up Children: Differences by Employment Type and Gender in the Tokyo Metropolitan Area
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作者 Jun Morio Koshi Isono +1 位作者 Masahiko Kikuchi Tetsuo Morita 《Journal of Transportation Technologies》 2024年第3期445-461,共17页
There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences i... There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children. 展开更多
关键词 Drop-Off and pick-up Employment Type GENDER Dual-Income Households Tokyo Metropolitan Area
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顶钵-夹茎组合式取苗装置设计与试验 被引量:1
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作者 张妮 张国忠 +3 位作者 付建伟 刘婉茹 陈立明 唐楠锐 《农业工程学报》 EI CAS CSCD 北大核心 2024年第3期50-61,共12页
针对现有钵苗自动移栽技术中,夹钵式取苗方式受钵体强度及盘根性差异影响易导致钵体破损,降低取苗成功率,夹茎式取苗方式受茎秆强度及钵体与穴盘之间黏附力影响易造成伤苗、钵体不能取出等问题,该研究提出了一种顶钵-夹茎组合取苗方式,... 针对现有钵苗自动移栽技术中,夹钵式取苗方式受钵体强度及盘根性差异影响易导致钵体破损,降低取苗成功率,夹茎式取苗方式受茎秆强度及钵体与穴盘之间黏附力影响易造成伤苗、钵体不能取出等问题,该研究提出了一种顶钵-夹茎组合取苗方式,并进行了结构设计、装置试制与试验优化。对辣椒穴盘苗茎秆和钵体力学特性进行了测试,得到茎秆拉伸和径向压缩力学特性,及钵体拉拔与压缩力学特性,并建立了顶钵-夹茎组合式取苗装置在顶与夹过程中钵体和茎秆的受力模型,对取苗装置关键参数进行了设计。搭建试验台架,以“中农绿亨线椒363”穴盘苗为对象,以钵体含水率、取苗频率和顶钵高度为影响因素开展正交试验,结果表明经顶钵-夹茎取苗后的穴盘苗生长状态良好,确定最优水平为含水率45%,取苗频率60株/min,顶钵高度10 mm,该条件下钵体破损率为1.98%,取苗成功率为98%。田间试验表明平均取苗成功率为93.05%,株距合格率为88.17%。研究可为辣椒、番茄等旱地作物穴盘苗移栽技术改进优化提供参考。 展开更多
关键词 农业机械 移栽机 穴盘苗 取苗 顶钵-夹茎组合式
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