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Effect of Types and Orders of Electromagnetic Field Finite Element Meshes on Power Communication Harmonic Parameters Calculation Results of Tubular Hydrogenerators
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作者 Fan Zhennan Chen Jie +1 位作者 Zhou Zhiting Yang Yong 《China Communications》 SCIE CSCD 2024年第10期288-300,共13页
In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication q... In generator design field,waveform total harmonic distortion(THD)and telephone harmonic factor(THF)are parameters commonly used to measure the impact of generator no-load voltage harmonics on the power communication quality.Tubular hydrogenerators are considered the optimal generator for exploiting low-head,high-flow hydro resources,and they have seen increasingly widespread application in China's power systems recent years.However,owing to the compact and constrained internal space of such generators,their internal magnetic-field harmonics are pronounced.Therefore,accurate calculation of their THD and THF is crucial during the analysis and design stages to ensure the quality of power communication.Especially in the electromagnetic field finite element modeling analysis of such generators,the type and order of the finite element meshes may have a significant impact on the THD and THF calculation results,which warrants in-depth research.To address this,this study takes a real 34 MW large tubular hydrogenerator as an example,and establishes its electromagnetic field finite element model under no-load conditions.Two types of meshes,five mesh densities,and two mesh orders are analyzed to reveal the effect of electromagnetic field finite element mesh types and orders on the calculation results of THD and THF for such generators. 展开更多
关键词 calculation results electromagnetic field finite element meshes power communication harmonic parameters tubular hydrogenerator types and orders
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Italian textile machinery orders remain stable in Q1 2024
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《China Textile》 2024年第3期27-27,共1页
For Italian textile machinery sector,2024 has begun without anything seemingly special.The first quarter has seen the orders index,as reported by the Economics Department of ACIMIT-the Association of Italian Textile M... For Italian textile machinery sector,2024 has begun without anything seemingly special.The first quarter has seen the orders index,as reported by the Economics Department of ACIMIT-the Association of Italian Textile Machinery Manufacturers-remain stationary compared to the same period the previous year.In absolute terms,the index came in at 61.2 points(basis:2021=100). 展开更多
关键词 ITALIAN orders MACHINERY
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基于Ordered Probit模型的人车冲突安全影响因素研究
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作者 裴玉龙 杜小敏 沈威宇 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第3期181-187,共7页
为探究和定量分析人车冲突严重程度的影响因素,通过采集3个信号交叉口的人车冲突视频数据,利用T-Analyst标定人车轨迹并计算冲突指标(PET),采用85%位累计频率曲线法划分人车冲突等级;从人、车、路及环境特征中选取10个因素作为变量,构建... 为探究和定量分析人车冲突严重程度的影响因素,通过采集3个信号交叉口的人车冲突视频数据,利用T-Analyst标定人车轨迹并计算冲突指标(PET),采用85%位累计频率曲线法划分人车冲突等级;从人、车、路及环境特征中选取10个因素作为变量,构建Ordered Probit模型,以确立人车冲突严重程度的显著影响因素,并通过边际效应定量分析不同显著因素的影响程度。研究结果表明:行人闯红灯情况、年龄、行人交通量、人行道占用情况、人行道起点终点、车辆速度变化及车流量是人车冲突严重程度的显著因素,相较于各自参考量,行人闯红灯、车辆加速通过冲突点、人行道起点及老年人造成严重冲突的概率分别增加8.2%,5.9%,5.1%,4.4%;相较于低流量的交通流,较高流量的车流和行人交通流使得严重冲突的概率分别增加3.7%,2.5%,但人行道占用使得严重冲突的概率下降6.8%。研究结果可为信号交叉口行人过街交通安全设施的设计和实施提供理论依据。 展开更多
关键词 信号交叉口 行人安全 人车冲突严重度 ordered Probit模型 边际效应
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基于Ordered Logit模型的民办高校科研成果转化影响因素研究
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作者 张二丽 黄静 +1 位作者 王倩 陈彬彬 《河南财政金融学院学报(自然科学版)》 2024年第2期35-41,共7页
为研究民办高校科研成果转化影响因素,在专家访谈和实地调研的基础上,对K高校、C高校、B高校、Z高校等民办高校教师发放调查问卷收集数据,应用Ordered Logit模型对其影响因素进行了实证分析。分析发现,科研经费支持力度与科研成果数量... 为研究民办高校科研成果转化影响因素,在专家访谈和实地调研的基础上,对K高校、C高校、B高校、Z高校等民办高校教师发放调查问卷收集数据,应用Ordered Logit模型对其影响因素进行了实证分析。分析发现,科研经费支持力度与科研成果数量之间呈正相关关系,高校科研平台设置与服务地方经济建设之间呈正相关关系,高校科研管理制度与科研成果转化成效之间呈正相关关系。由此得出结论:我国民办高校科研成果转化与服务地方经济能力有待提升,民办高校科研成果转化的金融支持不够灵活、公共服务平台不够健全,完善民办高校科研管理制度是提高科研成果转化效率的重要保障。 展开更多
关键词 民办高校 科研成果 转化 ordered Logit模型
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ON GENERALIZED ORDERS AND GENERALIZED TYPES OF DIRICHLET SERIES IN THE RIGHT HALF-PLANE 被引量:15
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作者 霍颖莹 孔荫莹 《Acta Mathematica Scientia》 SCIE CSCD 2014年第1期175-182,共8页
In the paper, generalized orders and generalized types of Dirichlet series in the right half-plane are given. Some interesting relationships on maximum modulus, the maximum term and the coefficients of entire function... In the paper, generalized orders and generalized types of Dirichlet series in the right half-plane are given. Some interesting relationships on maximum modulus, the maximum term and the coefficients of entire function defined by Dirichlet series of in the right half-plane are obtained. 展开更多
关键词 Dirichlet series order type slow growth
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The Lower Orders of Dirichlet and Random Dirichlet Series 被引量:7
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作者 Yu Jiarong (Department of Mathematics,Wuhan University,Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期1-8,共8页
The formulas of the lower orders of Dirichlet series are given by means of the exponents and the convex regularized sequences of the logarithms and the convex regularized sequences of the logarithms of the moduli of t... The formulas of the lower orders of Dirichlet series are given by means of the exponents and the convex regularized sequences of the logarithms and the convex regularized sequences of the logarithms of the moduli of the coefficients. Corresponding results are obtained for some random Dirichlet series. 展开更多
关键词 Dirichlet series random Dirichlet series lower order convex regularization
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Synchronization of chaotic systems with different orders 被引量:14
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作者 吕翎 栾玲 郭治安 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期346-351,共6页
A controller is designed to realize the synchronization between chaotic systems with different orders. The structure of the controller, the error equations and the Lyapunov functions are determined based on stability ... A controller is designed to realize the synchronization between chaotic systems with different orders. The structure of the controller, the error equations and the Lyapunov functions are determined based on stability theory. Hyperchaotic Chen system and Rossler system are taken for example to demonstrate the method to be effective and feasible. Simulation results show that all the state wriables of Rossler system can be synchronized with those of hyperchaotic Chen system by using only one controller, and the error signals approach zero smoothly and quickly. 展开更多
关键词 chaos synchronization hyperchaotic Chen system Rossler system chaotic systems with different orders
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CONTROLLABILITY AND OPTIMALITY OF LINEAR TIME-INVARIANT NEUTRAL CONTROL SYSTEMS WITH DIFFERENT FRACTIONAL ORDERS 被引量:3
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作者 丁小丽 Juan J.NIETO 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1003-1013,共11页
Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The ex... Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results. 展开更多
关键词 CONTROLLABILITY OPTIMALITY neutral equations different fractional orders
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Definition of fine roots on the basis of the root anatomy, diameter,and branch orders of one-year old Fraxinus mandshurica seedlings 被引量:3
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作者 Xinzhu Du Xing Wei 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1321-1327,共7页
Fine roots are important in root absorption of nutrient and water,and in root turnover.Accurate definition of fine roots is a prerequisite to improved estimation of the physiological and ecological functions of forest... Fine roots are important in root absorption of nutrient and water,and in root turnover.Accurate definition of fine roots is a prerequisite to improved estimation of the physiological and ecological functions of forest ecosystems.Root development and physiological functions are reflections of root anatomical structure.In this study,the anatomical structures of different root orders were analyzed by examining paraffin sections of one-year old Fraxinus mandshurica seedlings.One-year-old F.mandshurica seedlings had over five root orders.The root anatomical structures of all orders showed more differences.First and second order roots consisted of four sections: the epidermis,cortex,pericycle,and vascular bundles.Fourth and fifth order roots were mainly composed of the skin and peripheral vascular bundles(including the xylem and phloem).Third order roots had root epidermal and cortical structures,but the quantity and integrity of the cortical cells were inferior to those of the first and second order roots,and superior to those of the fourth and fifth order roots.All the first and second order roots and some third order roots with discontinuous cork layer(〈0.4 mm in diameter),but not the fourth and fifth order roots,were the fine roots of one-year old F.mandshurica seedlings.Although they had similar diameters,different portions of root systems had different anatomical structures and therefore,vary in capacity to absorb water and nutrients.Fine roots were accurately defined by root diameter,branch orders,and anatomical structural features of one-year old F.mandshurica seedlings. 展开更多
关键词 Fine root Root order Fraxinus mandshurica Anatomical structure
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A RECOGNITION OF SIMPLE GROUPS PSL(3,q) BY THEIR ELEMENT ORDERS 被引量:2
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作者 M.R.Darafsheh A.R.Moghaddamfar A.R.Zokayi 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期45-51,共7页
For any group G, denote byπe(G) the set of orders of elements in G. Given a finite group G, let h(πe (G)) be the number of isomorphism classes of finite groups with the same set πe(G) of element orders. A group G i... For any group G, denote byπe(G) the set of orders of elements in G. Given a finite group G, let h(πe (G)) be the number of isomorphism classes of finite groups with the same set πe(G) of element orders. A group G is called k-recognizable if h(πe(G)) = k <∞, otherwise G is called non-recognizable. Also a 1-recognizable group is called a recognizable (or characterizable) group. In this paper the authors show that the simple groups PSL(3,q), where 3 < q≡±2 (mod 5) and (6, (q-1)/2) = 1, are recognizable. 展开更多
关键词 Element order prime graph projective special linear group
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Different dissecting orders of the pulmonary bronchus and vessels during right upper lobectomy are associated with surgical feasibility and postoperative recovery for lung cancer patients 被引量:8
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作者 Hao-Ran Zhai Xue-Ning Yang +10 位作者 Qiang Nie Ri-Qiang Liao Song Dong Wei Li Ben-Yuan Jiang Jin-Ji Yang Qing Zhou Hai-Yan Tu Xu-Chao Zhang Yi-Long Wu Wen-Zhao Zhong 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第10期468-477,共10页
Background: Right upper lobectomy(RUL) for lung cancer with di erent dissecting orders involves the most vari?able anatomical structures, but no studies have analyzed its e ects on postoperative recovery. This study c... Background: Right upper lobectomy(RUL) for lung cancer with di erent dissecting orders involves the most vari?able anatomical structures, but no studies have analyzed its e ects on postoperative recovery. This study compared the conventional surgical approach, VAB(dissecting pulmonary vessels first, followed by the bronchus), and the alter?native surgical approach, a BVA(dissecting the posterior ascending arterial branch first, followed by the bronchus and vessels) on improving surgical feasibility and postoperative recovery for lung cancer patients.Methods: According to the surgical approach, consecutive lung cancer patients undergoing RUL were grouped into a BVA and VAB cohorts. Their clinical, pathologic, and perioperative characteristics were collected to compare periop?erative outcomes.Results: Three hundred one patients were selected(109 in the a BVA cohort and 192 in the VAB cohort). The mean operation time was shorter in the a BVA cohort than in the VAB cohort(164 vs. 221 min, P < 0.001), and less blood loss occurred in the a BVA cohort(92 vs. 141 m L, P < 0.001). The rate of conversion to thoracotomy was lower in the a BVA cohort than in the VAB cohort(0% vs. 11.5%, P < 0.001). The mean duration of postoperative chest drainage was shorter in the a BVA cohort than in the VAB cohort(3.6 vs. 4.5 days, P rvival was n= 0.001). The rates of postoperative complica?tions were comparable(P = 0.629). The median overall suot arrived in both cohorts(P > 0.05). The median disease?free survival was comparable for all patients in the two cohorts(not arrived vs. 41.97 months) and for patients with disease recurrences(13.25 vs. 9.44 months)(both P > 0.05). The recurrence models in two cohorts were also comparable for patients with local recurrences(6.4% vs. 7.8%), distant metastases(10.1% vs. 8.3%), and both(1.8% vs. 1.6%)(all P > 0.05).Conclusions: Dissecting the right upper bronchus before turning over the lobe repeatedly and dissecting veins via the a BVA approach during RUL would promote surgical feasibility and achieve comparable postoperative recovery for lung cancer patients. 展开更多
关键词 Lung cancer Dissecting order Video-assisted thoracic surgery Pulmonary veins BRONCHUS
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On the Variational Problems of the Functionals with Derivatives of Higher Orders and Undetermined Boundary 被引量:1
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作者 老大中 谈天民 《Journal of Beijing Institute of Technology》 EI CAS 2007年第1期116-121,共6页
According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of va... According to the necessary condition of the functional taking the extremum, that is its first variation is equal to zero, the variational problems of the functionals for the undetermined boundary in the calculus of variations are researched, the functionals depend on single argument, arbitrary unknown functions and their derivatives of higher orders. A new view point is posed and demonstrated, i.e. when the first variation of the functional is equal to zero, all the variational terms are not independent to each other, and at least one of them is equal to zero. Some theorems and corollaries of the variational problems of the functionals are obtained. 展开更多
关键词 calculus of variations FUNCTIONAL variational problems derivatives of higher orders undetermined boundary
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Orders of Automorphism Groups of the p^6 Groups of Family Φ_(24) 被引量:1
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作者 赵振华 苏翃 邱利琼 《Journal of Southwest Jiaotong University(English Edition)》 2008年第4期419-423,共5页
Using the metabelian property, regularity, p-commutativity and some properties of congruence, this paper gave the orders of automorphism groups of family Ф24, which are the groups of order p^6 determined by Rodney Ja... Using the metabelian property, regularity, p-commutativity and some properties of congruence, this paper gave the orders of automorphism groups of family Ф24, which are the groups of order p^6 determined by Rodney James, where p denotes an odd prime. 展开更多
关键词 P-GROUP AUTOMORPHISM Defining relations order
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Two Important Classes of p-groups and the Orders of Their Automorphism Groups 被引量:2
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作者 BAN Gui-ning ZHANG Xin-zheng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期491-493,共3页
In the paper we obtain two infinite classes of p-groups, calculate the orders of their automorphism groups and correct a mistake(perhaps misprinted) of Rodney James' paper in 1980.
关键词 finite group P-GROUP AUTOMORPHISM order CLASSIFICATION
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Efficient Quantum Secure Communication Protocol by Rearranging Particle Orders 被引量:2
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作者 GAO Gan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期845-847,共3页
We propose a quantum secure communication protocol by using three-particle GHZ states. In this protocol, we utilize the ideas of the rearranging orders and the sequence transmission. The sender of messages, Alice, fir... We propose a quantum secure communication protocol by using three-particle GHZ states. In this protocol, we utilize the ideas of the rearranging orders and the sequence transmission. The sender of messages, Alice, first disturbs the particle orders in an initial sequence, and then sends the sequence of the disturbed orders to the receiver of messages, Bob. Under Alice's introduction, Bob rearranges the sequence back to the initial sequence. By making a GHZ state measurement on each of the three particles in turn, Bob can attain Alice's secret messages. In addition, we still calculate the efficiency of our three-particle GHZ protocol and generalize it to the case using multi-particle GHZ state. 展开更多
关键词 rearranging orders quantum secure communication
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Flow shop rescheduling problem under rush orders 被引量:2
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作者 胡燕海 严隽琪 +1 位作者 叶飞帆 于军合 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第10期1040-1046,共7页
In the environment of customization, disturbances such as rush orders and material shortages often occur in the manufacturing system, so rescheduling is necessary for the manufacturing system. The rescheduling methodo... In the environment of customization, disturbances such as rush orders and material shortages often occur in the manufacturing system, so rescheduling is necessary for the manufacturing system. The rescheduling methodology should be able to dispose of the disturbance efficiently so as to keep production going smoothly. This aims researching flow shop rescheduling problem (FSRP) necessitated by rush orders. Disjunctive graph is employed to demonstrate the FSRP. For a flow shop processing n jobs, after the original schedule has been made, and z out of n jobs have been processed in the flow shop, x rush orders come, so the original n jobs together with x rush orders should be rescheduled immediately so that the rush orders would be processed in the shortest time and the original jobs could be processed subject to some optimized criteria. The weighted mean flow time of both original jobs and rush orders is used as objective function. The weight for rush orders is much bigger than that of the original jobs, so the rush orders should be processed early in the new schedule. The ant colony optimization (ACO) algorithm used to solve the rescheduling problem has a weakness in that the search may fall into a local optimum. Mutation operation is employed to enhance the ACO performance. Numerical experiments demonstrated that the proposed algorithm has high computation repeatability and efficiency. 展开更多
关键词 Flow shop rescheduling Dynamic scheduling Rush order Ant colony optimization Mutation operation
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Boundary Hamiltonian Theory for Gapped Topological Orders 被引量:2
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作者 胡愈挺 万义顿 吴咏时 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期207-211,共5页
We report our systematic construction of the lattice Hamiltonian model of topological orders on open surfaces, with explicit boundary terms. We do this mainly for the Levin-Wen string-net model. The full Hamiltonian i... We report our systematic construction of the lattice Hamiltonian model of topological orders on open surfaces, with explicit boundary terms. We do this mainly for the Levin-Wen string-net model. The full Hamiltonian in our approach yields a topologically protected, gapped energy spectrum, with the corresponding wave functions robust under topology-preserving transformations of the lattice of the system. We explicitly present the wavefunctions of the ground states and boundary elementary excitations. The creation and hopping operators of boundary quasi-particles are constructed. It is found that given a bulk topological order, the gapped boundary conditions are classified by Frobenius algebras in its input data. Emergent topological properties of the ground states and boundary excitations are characterized by (bi-) modules over Frobenius algebras. 展开更多
关键词 Boundary Hamiltonian Theory for Gapped Topological orders
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Lacanian Reinterpretation of Charlotte Perkins Gilman's The Yellow Wallpaper based on Theories of “Mirror Stage” and “Three Orders”
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作者 詹佳佳 《科学大众(智慧教育)》 2016年第1期137-139,78,共4页
The Yellow Wallpaper was a representative work of feminist literature by Charlotte Perkins Gilman.In the novel,the heroine under great repression gradually awakes to seek self identification and revolt against the pat... The Yellow Wallpaper was a representative work of feminist literature by Charlotte Perkins Gilman.In the novel,the heroine under great repression gradually awakes to seek self identification and revolt against the patriarchy.Many researchers have conducted studies from perspectives of feminism,image,theme and structure of the novel.This paper aims to employ Lacan’s"mirror stage"theory and"three orders"theory to analyze the story.Through observing the image of the"confined woman"in the"mirror"(the yellow wallpaper),her awareness of"selfhood"is gradually awakened:she lives in the Symbolic Order where the patriarchy has imposed many restrictions on her.Unable to live in such a world,while the Real is also incomprehensible,what she could do is to totally immerse herself in the Imaginary Order.That’s why she is creeping like a child. 展开更多
关键词 Mirror stage Identification EGO "Three orders"
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Freight Vehicle Routing Optimization for Sporadic Orders Using Floating Car Data 被引量:1
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作者 常晶晶 彭仲仁 孙健 《Journal of Donghua University(English Edition)》 EI CAS 2013年第2期96-102,共7页
The increasing popularity of e-commerce brings large volumes of sporadic orders from different customers,which have to be handled by freight trucks and distribution centers. To improve the level of service and reduce ... The increasing popularity of e-commerce brings large volumes of sporadic orders from different customers,which have to be handled by freight trucks and distribution centers. To improve the level of service and reduce the total shipping cost as well as traffic congestions in urban area, flexible methods and optimal vehicle routing strategies should be adopted to improve the efficiency of distribution effort. An optimization solution for vehicle routing and scheduling problem with time window for sporadic orders (VRPTW- S) was provided based on time-dependent travel time extracted from floating car data (FCD) with ArcGIS platform. A VRPTW-S model derived from the traditional vehicle routing problem was proposed, in which uncertainty of customer orders and travel time were considered. Based on this model, an advanced vehicle routing algorithm was designed to solve the problem. A case study of Shenzhen, Guangdong province, China, was conducted to demonstrate the vehicle operation flow,in which process of FCD and efficiency of delivery systems under different situations were discussed. The final results demonstrated a good performance of application of time-dependent travel time information using FCD in solving vehicle routing problems. 展开更多
关键词 freight routing and scheduling time-dependent travel time floating car data (FCD) sporadic order ArcGIS
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Analyze Light in August by Lacan's Theory of Three Orders
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作者 包亚楠 刘香 《海外英语》 2017年第11期161-163,共3页
Being one of the greatest 20thcentury writers,William Faulkner created many novels which were given high appraisal and remained popular up to today.The broad themes which are covered in Faulkner’s novels cannot be ne... Being one of the greatest 20thcentury writers,William Faulkner created many novels which were given high appraisal and remained popular up to today.The broad themes which are covered in Faulkner’s novels cannot be neglected,including the racial and religious belief in American society,the fading of the traditional Southern value and the corrosive influence of the rapid industrialization over the human being.Among these important themes,Faulkner also paid enough attention to the theme about how the individual can achieve his or her own identity.In the light of Lacan’s theory of Three Orders,this paper tries to evaluate Faulkner’s discussion over the formation of individual’s identity with Gail Hightower as the example. 展开更多
关键词 Light in August Formation of Identity Three orders
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