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Optimizing Work Zones for Two-Lane Urban Road maintenance Projects

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Tsinghua Science and Technology 2008年第5期13卷 644-650页

作者：黄谦石京 Institute of Transportation Engineering Department of Civil EngineeringTsinghua University

Road maintenance work brings costs to the government and delays to users. The setting up of work zones often leads to severe congestion during peak hours, especially in busy urban areas. A road maintenance delay model is presented here that includes consideration of excessive traffic flow and non-motorists. Atrial-and-error method is used to find the optimal work zone length and the best work starting time to minimize the total cost of maintenance and delays. A numerical example with a sensitivity analysis is also given. The results show that optimal starting time is not sensitive to the flow speed and the increase of work zone speeds sharply reduces the total cost when the road is congested.

关键词： maintenance work zone delay non-motor interference optimizing

Equivalence of Some Different maintenance Activities in Single-Machine Scheduling

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Journal of the Operations Research Society of China 2018年第4期6卷 545-556页

作者： Juan Zou Jin-Jiang Yuan School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China School of Mathematical Sciences Qufu Normal UniversityQufu 273165ShandongChina

We study single-machine scheduling problems with a single maintenance activity(MA)of length p0 under three types of assumptions:(A)the MA is required in a fixed time interval[T−p0,T]with T≥p0 and the job processing is of preemptive and resumable;(B)the MA is required in a relaxed time interval[0,T]with T≥p0 and the job processing is of nonpreemptive;(C)the MA is required in a relaxed time interval[T0,T]with 0≤T0≤T−p0 and the job processing is of nonpreemptive.We show in this paper that,up to the time complexity for solving scheduling problems,assumptions(A)and(B)are equivalent,and moreover,if T−(T0+p0)is greater than or equal to the maximum processing time of all jobs,the assumption(C)is also equivalent to(A)and(B).As an application,we study the scheduling for minimizing the weighted number of tardy jobs under the above three assumptions,respectively,and present corresponding time-complexity results.

关键词： Scheduling maintenance Dynamic programming

The Change and Prospect of “Automobile Electromechanical maintenance Skills Competition” under the Chinese Model

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Journal of Mechanical Engineering Research 2019年第2期2卷 8-13页

作者： Jianguo Feng Sichuan Vocational And Technical College of Communications chengdusichuan611130China

This paper analyzes the origin, status, changes and characteristics of theautomotive electromechanical maintenance skills competition in China,and presents the developing trend in the future.

关键词： Automobile Electromechanical maintenance Skill contest Change Development

A Survey on Network Operation and maintenance Quality Evaluation Models

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ZTE Communications 2019年第4期17卷 56-61页

作者： LIU Lixia WU Muyang JI Feng LIU Zheng ZTE Corporation NanjingJiangsu 210012China Nanjing University of Posts and Telecommunications NanjingJiangsu 210023China

The evaluation of network operation and maintenance quality is an important reference for carriers to improve their service.However,the traditional evaluation methods involve so much human participation that it cannot cope with the explosive amount of data.Therefore,both the major carriers and researchers are trying to find solutions to evaluate the quality of network operation and maintenance more objectively and accurately.In this paper,we analyze the general process of quality evaluation models for network operation and maintenance.The process has four steps:1)selection of evaluation indicators;2)data process for chosen indicators;3)determination of indicator weights;4)establishment of evaluation models.We further describe the working principle of each step,especially the methods for indicator selection and weight determination.Finally,we review the recently proposed evaluation models and the international stan dards of network operation and maintenance quality evaluation.

关键词： quality evaluation network operation and maintenance quality of service indicator selection weight determination

Research of maintenance Task Interval Optimization of Elevator Hydraulic Actuation System

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International Journal of Plant Engineering and Management 2019年第3期24卷 169-179页

作者： CHEN Rui WANG Yiping SUN Tieyuan Shanghai Aircraft Customer Service Co. Ltd.

In order to solve the best maintenance interval problem of the elevator hydraulic actuation systems on civil aircraft, a method based on reliability and cost minimum is introduced in this paper. The estimation of system reliability is presented by using two-parameter Weibull distributions. The parameters are estimated by using Weibull probability statistical analysis and the practical operational data. Then, the maintenance optimization model isformulated where the objective function is to minimize the expected schedule maintenance cost in a time unit. The results of numerical example show that the proposed model could scheme the optimal maintenance intervals for the considered system when the parameters are given. This research has certain significance in theoryand engineering practice.

关键词： elevator hydraulic actuation system maintenance interval minimum cost Weibull

多样性维持与整合缺失:多元文化背景下元代民族社会教育政策分析

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西北师大学报（社会科学版） 2010年第6期47卷 44-50页

作者：张学强王文娟西北师范大学西北少数民族教育发展研究中心甘肃兰州730070

元代是一个文化多样性特征极其突出的社会,如何面对文化的多样性成为摆在统治者面前的一个重要问题。通过对元代的多元文化政策及"各依其本俗而治"的少数民族社会教育政策及其与国家整合的关系分析,认为元代"各依其本俗而治"的少数民族... 详细信息

元代是一个文化多样性特征极其突出的社会,如何面对文化的多样性成为摆在统治者面前的一个重要问题。通过对元代的多元文化政策及"各依其本俗而治"的少数民族社会教育政策及其与国家整合的关系分析,认为元代"各依其本俗而治"的少数民族社会教育政策主要是为了统治的暂时稳定而实施的,偏重于文化多样性现状的维持,而于国家的整合无太多的考虑。

关键词：文化多样性国家整合缺失多元文化背景元代少数民族社会教育政策分析 Integration Lack maintenance Yuan Dynasty Ethnic Minorities Education Policy Social 文化的多样性多元文化政策多样性特征统治者关系分析问题

Approximate Approach to Deal with the Uncertainty in Integra ted Production Scheduling and maintenance Planning

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Journal of Shanghai Jiaotong university(Science) 2020年第1期25卷 106-117页

作者：崔维伟 School of Management Shanghai UniversityShanghai 200444China

This paper deals with the integration problem between production scheduling and maintenance planning in a single machine,where the impact of failure uncertainty is considered.The objective is to minimize the weighted sum of quality robustness and solution robustness,which is determined by the jobs1 sequence,preventive maintenances,position and buffer time in the schedule.Then,a three-stage algorithm is devised to solve the problem,where the gradient descent algorithm based on an effective surrogate measure is developed in the second st age.The numerical experiments show that the deviation of the approximate approach is very small,as compared with the exact solution obtained by CPLEX.The balance between quality robustness and solution robustness and the distribution of buffer time in different scenarios are shown in a case study.It validates the necessity and effectiveness of the consideration of robustness in the industrial practice.

关键词： production scheduling maintenance policy proactive uncertainty

maintenance Strategies and Spare Parts Inventory Management for Use of Reconditioned Items

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Engineering（科研） 2022年第8期14卷 360-370页

作者： Mamadou Sagne Mouhamed Fadel Niang Doctoral School for Sustainable Development and Society Iba Der Thiam University Thies Senegal

The maintenance management of construction equipment occupies a prominent place in the overall strategy for managing the equipment fleet. It is also linked to the management of the stock of spare parts and particularly reconditioned spare parts. Because of the relatively low purchase cost of these, most companies are tempted by this option. The purpose of this article is precisely to study the impact of this category of parts in the stock and also in the optimization of maintenance costs, knowing that to do this;their use must obey certain constraints. It is therefore important to be able to characterize these reconditioned parts by estimating their optimal age, and studying their advantages and also their limits. The determination of the optimal age of reconditioned parts will be such that the total cost of replacement with used parts is at most equal to the total cost of replacement with new parts at the end of the operating period.

关键词： Strategies maintenance Spare Parts Reconditioned

Predictive maintenance of Manned Spacecraft Through Remaining Useful Life Estimation Technique

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Aerospace China 2018年第3期19卷 3-10页

作者： CHEN Runfeng YANG Hong Institute of Manned Space System Engineering Beijing 100094

Manned spacecraft pose challenges in terms of extremely high safety and reliability, and with the growth of system complexity and longer on-orbit operation time, the traditional management mode, such as monitoring the threshold of parameter passively, is difficult to meet the required safety standards. Predictive maintenance, which analyzes the system heath trend and estimates remaining useful life(RUL) to establish maintenance strategies ahead of time before failure occurs, is a new mode to approach maintenance tasks. Here, a predictive maintenance strategy for complex manned spacecraft is proposed based on the remaining useful life estimation technique. Firstly, a health index is established based on an abundance of telemetry data, reflecting the system's current health state. Secondly, we map the health index to the remaining useful life through system degradation modelling, taking into consideration both the system's stochastic deterioration and uncertainty. The maintenance and management strategies are then made based on the calculated distribution of RUL time. Finally, a case study on Chinese space station energy system predictive maintenance is presented.

关键词： remaining useful life predictive maintenance Chinese space station