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Risk stratification of renal transplant recipients using routine parameters: Implication of learning from SARS-CoV-2 into transplant follow-up program
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作者 Abbas Ghazanfar Madiha Abbas +1 位作者 Md Walid Hussain Malik Kayal 《World Journal of Transplantation》 2023年第6期344-356,共13页
BACKGROUND Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is a global pandemic that is associated with a high risk of morbidity and mortality among recipients of solid organ transplantation.In th... BACKGROUND Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is a global pandemic that is associated with a high risk of morbidity and mortality among recipients of solid organ transplantation.In the course of acute SARS-CoV-2 infection,various laboratory markers have been identified as predictors for high risk of mortality.AIM To risk stratify renal transplant recipients(RTxR)using general demographic parameters,comorbidities and routine laboratory markers for the severity of the disease and its outcomes.We believe that learning about these routinely monitored parameters can help us plan better strategies for the RTxR follow-up program.METHODS This present study includes RTxR who acquired SARS-CoV-2 infection from March 2020 to February 2021.We recorded the basic demographics,comorbidities and routine laboratory markers.We investigated the impact of SARS-CoV-2 infection on RTxRs and risk-stratified the progression of disease severity and outcomes in terms of recovery or mortality.RESULTS From 505 RTxRs in our renal transplant follow-up program,29(7.75%)RTxRs had PCR-positive SARS-CoV-2 infection.We recorded 8 deaths from SARS-CoV-2 infection giving an overall mortality rate of 1.6%but a significant 27.6%mortality in SARS-CoV-2 positive recipients.Age more than 68 years,non-Caucasian ethnicity and male gender were associated with a significant drop in survival probability;P≤0.001.<0.001 and<0.0001 respectively.87.5%of the deceased were diabetic;P≤0.0.0001.Estimated glomerular filtration rate of less than 26 mL/min/1.73 m2,serum albumin less than 20 g/L,Hemoglobin less than 9.6 g/L and serum calcium less than 1.70 mmol/L were all associated with significantly increased risk of mortality;P=0.0128,<0.001,<0.0001 and 0.0061 respectively.CONCLUSION This study has identified some routinely used modifiable parameters in predicting a higher risk of mortality and morbidity.This knowledge can be used in RTxR follow-up programs by addressing these parameters early to help reduce the morbidity and mortality in RTxRs. 展开更多
关键词 SARS-CoV-2 mortality Renal transplant recipients Glomerular filtration rate ANEMIA ALBUMIN Calcium Reducing morbidity and mortality Renal transplant follow-up program
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Design of Aided Decision-Making Program for Prioritizing Construction Projects in Urban Road Network Planning
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作者 任刚 王炜 顾志康 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期249-253,共5页
The importance and complexity of prioritizing construction projects (PCP) in urban road network planning lead to the necessity to develop an aided decision making program (ADMP). Cost benefit ratio model and stage rol... The importance and complexity of prioritizing construction projects (PCP) in urban road network planning lead to the necessity to develop an aided decision making program (ADMP). Cost benefit ratio model and stage rolled method are chosen as the theoretical foundations of the program, and then benefit model is improved to accord with the actuality of urban traffic in China. Consequently, program flows, module functions and data structures are designed, and particularly an original data structure of road ... 展开更多
关键词 prioritizing construction projects program design urban road network planning aided decision making
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A Hybrid Programming Model for Optimal Production Planning under Demand Uncertainty in Refinery 被引量:6
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作者 李初福 何小荣 +2 位作者 陈丙珍 徐强 刘朝玮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第2期241-246,共6页
Abstract Production planning under uncertainty is considered as one of the most important problems in plant-wide optimization. In this article, first, a stochastic programming model with uniform distribution assumptio... Abstract Production planning under uncertainty is considered as one of the most important problems in plant-wide optimization. In this article, first, a stochastic programming model with uniform distribution assumption is developed for refinery production planning under demand uncertainty, and then a hybrid programming model incorporating the linear programming model with the stochastic programming one by a weight factor is proposed. Subsequently, piecewise linear approximation functions are derived and applied to solve the hybrid programming model-under uniform distribution assumption. Case studies show that the linear approximation algorithm is effective to solve.the hybrid programming model, along with an error≤0.5% when the deviatiorgmean≤20%. The simulation results indicate that the hybrid programming model with an appropriate weight factor (0.1-0.2) can effectively improve the optimal operational strategies under demand uncertainty, achieving higher profit than the linear programming model and the stochastic programming one with about 1.3% and 0.4% enhancement, respectavely. 展开更多
关键词 production planning demand uncertainty stochastic programming linear programming hybrid programming
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A Cooperation-planning Model Based on Bilevel Programming Decision 被引量:1
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作者 ZHANG Jianfeng ZHOU Lei BAO Zhenqiang BIAN Wenyu LI Xiangqing Information Engineering College,Yangzhou University,Yangzhou 225009,China, 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期940-945,共6页
This paper is based on a resource constrained active network project;the constraint of the local resource and the time constraint of the cooperation resource are considered simultaneously.And the respective benefit of... This paper is based on a resource constrained active network project;the constraint of the local resource and the time constraint of the cooperation resource are considered simultaneously.And the respective benefit of the manager and cooperation partners is also considered simultaneously.And a cooperation planning model based on bilevel multi-objective programming is de- signed,according to the due time and total cost.And an extended CNP based on the permitted range for resource and time requests is presented.A larger task set in scheduling cycle is on the permitting for the request of cooperation resource and time while the task manager itself may be permitted biding for tasks.As a result,the optimization space for the cooperation planning is enlarged.So not every bidding task is successfully bid by invitee,and the task manager itself takes on some bidding tasks.Finally,the genetic algorithm is given and the validity and feasibility of the model is proved by a case. 展开更多
关键词 bilevel programMING DECISION COOPERATION planning GENETIC algorithm RANGE for RESOURCE and time sequest
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Study on the Programming Standard for Ecological Rescue in General Land Use Planning 被引量:1
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作者 Bai Wei Hao Jinmin Zhang Qiuping 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第4期43-47,共5页
This paper aims at establishing the operation idea based on the analysis of the connotation,principles and reference indexes for programming standard for ecological rescue.The paper puts forward that the programming s... This paper aims at establishing the operation idea based on the analysis of the connotation,principles and reference indexes for programming standard for ecological rescue.The paper puts forward that the programming standard should take into account the natural,social and economic reference indexes,and modifies the scale and distribution of the ecological rescue according to the order of ecological safety,social safety and economic development.The paper suggests that the land planning department should strengthen the study and datum accumulation in order to establish the technology regulations of programming standard of the ecological rescue. 展开更多
关键词 land use planning IDEA SUM up ECOLOGICAL RESCUE programMING STANDARD
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Novel integrated optimization algorithm for trajectory planning of robot manipulators based on integrated evolutionary programming 被引量:1
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作者 XiongLUO XiaopingFAN HengZHANG TefangCHEN 《控制理论与应用(英文版)》 EI 2004年第4期319-331,共13页
Optimal trajectory planning for robot manipulators plays an important role in implementing the high productivity for robots. The performance indexes used in optimal trajectory planning are classified into two main cat... Optimal trajectory planning for robot manipulators plays an important role in implementing the high productivity for robots. The performance indexes used in optimal trajectory planning are classified into two main categories: optimum traveling time and optimum mechanical energy of the actuators. The current trajectory planning algorithms are designed based on one of the above two performance indexes. So far, there have been few planning algorithms designed to satisfy two performance indexes simultaneously. On the other hand, some deficiencies arise in the existing integrated optimi2ation algorithms of trajectory planning. In order to overcome those deficiencies, the integrated optimization algorithms of trajectory planning are presented based on the complete analysis for trajectory planning of robot manipulators. In the algorithm, two object functions are designed based on the specific weight coefficient method and ' ideal point strategy. Moreover, based on the features of optimization problem, the intensified evolutionary programming is proposed to solve the corresponding optimization model. Especially, for the Stanford Robot,the high-quality solutions are found at a lower cost. 展开更多
关键词 Trajectory planning Integrated optimization Evolutionary programming Robot manipulator
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HEURISTIC MODELING FOR A DYNAMIC AND GOAL PROGRAMMING IN PRODUCTION PLANNING OF CONTINUOUS MANUFACTURING SYSTEMS 被引量:2
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作者 JAHAN A ABDOLSHAH M 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第5期110-113,共4页
At the first sight it seems that advanced operation research is not used enough in continuous production systems as comparison with mass production, batch production and job shop systems, but really in a comprehensive... At the first sight it seems that advanced operation research is not used enough in continuous production systems as comparison with mass production, batch production and job shop systems, but really in a comprehensive evaluation the advanced operation research techniques can be used in continuous production systems in developing countries very widely, because of initial inadequate plant layout, stage by stage development of production lines, the purchase of second hand machineries from various countries, plurality of customers. A case of production system planning is proposed for a chemical company in which the above mentioned conditions are almost presented. The goals and constraints in this issue are as follows: (1) Minimizing deviation of customer's requirements. (2) Maximizing the profit. (3) Minimizing the frequencies of changes in formula production. (4) Minimizing the inventory of final products. (5) Balancing the production sections with regard to rate in production. (6) Limitation in inventory of raw material. The present situation is in such a way that various techniques such as goal programming, linear programming and dynamic programming can be used. But dynamic production programming issues are divided into two categories, at first one with limitation in production capacity and another with unlimited production capacity. For the first category, a systematic and acceptable solution has not been presented yet. Therefore an innovative method is used to convert the dynamic situation to a zero- one model. At last this issue is changed to a goal programming model with non-linear limitations with the use of GRG algorithm and that's how it is solved. 展开更多
关键词 Heuristic model Dynamic programming Goal programming production planning
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Quadratic Programming-based Approach for Autonomous Vehicle Path Planning in Space
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作者 CHEN Yang HAN Jianda WU Huaiyu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第4期665-673,共9页
Path planning for space vehicles is still a challenging problem although considerable progress has been made over the past decades.The major difficulties are that most of existing methods only adapt to static environm... Path planning for space vehicles is still a challenging problem although considerable progress has been made over the past decades.The major difficulties are that most of existing methods only adapt to static environment instead of dynamic one,and also can not solve the inherent constraints arising from the robot body and the exterior environment.To address these difficulties,this research aims to provide a feasible trajectory based on quadratic programming(QP) for path planning in three-dimensional space where an autonomous vehicle is requested to pursue a target while avoiding static or dynamic obstacles.First,the objective function is derived from the pursuit task which is defined in terms of the relative distance to the target,as well as the angle between the velocity and the position in the relative velocity coordinates(RVCs).The optimization is in quadratic polynomial form according to QP formulation.Then,the avoidance task is modeled with linear constraints in RVCs.Some other constraints,such as kinematics,dynamics,and sensor range,are included.Last,simulations with typical multiple obstacles are carried out,including in static and dynamic environments and one of human-in-the-loop.The results indicate that the optimal trajectories of the autonomous robot in three-dimensional space satisfy the required performances.Therefore,the QP model proposed in this paper not only adapts to dynamic environment with uncertainty,but also can satisfy all kinds of constraints,and it provides an efficient approach to solve the problems of path planning in three-dimensional space. 展开更多
关键词 path planning in three-dimensional space obstacle avoidance target pursuit relative velocity coordinates quadratic programming
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Study on path planning and compensation of off-line programming for thick walled curve welding
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作者 陈洪堂 李海超 +1 位作者 高洪明 吴林 《China Welding》 EI CAS 2015年第4期69-73,共5页
Thick walled curve welding are usually joined by multi-layer and multi-pass welding, which quality and efficiency could be improved by off-line programming of robot welding. However, the precision of off-line programm... Thick walled curve welding are usually joined by multi-layer and multi-pass welding, which quality and efficiency could be improved by off-line programming of robot welding. However, the precision of off-line programming welding path was decreased due to the deviation between the off-line planned welding path and the actual welding path. A path planning algorithm and a path compensation algorithm of multi-layer and multi-pass curve welding seam for off-line programming of robot welding are developed in this paper. Experimental results show that the robot off-line programming improves the welding efftcieney and precision for thick walled curve welding seam. 展开更多
关键词 robot welding off-line programming path planning path compensation
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Two-Phase Multi Objective Fuzzy Linear Programming Approach for Sustainable Irrigation Planning
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作者 D. G. Regulwar Jyotiba B. Gurav 《Journal of Water Resource and Protection》 2013年第6期642-651,共10页
The objective of the present study is to develop the irrigation planning model and to apply the same in the form of Two-Phase Multi Objective Fuzzy Linear Programming (TPMOFLP) approach for crop planning in command ar... The objective of the present study is to develop the irrigation planning model and to apply the same in the form of Two-Phase Multi Objective Fuzzy Linear Programming (TPMOFLP) approach for crop planning in command area of Jayakwadi Project Stage I, Maharashtra State, India. The development of TPMOFLP model is on the basis of various Linear Programming (LP) models and Multi Objective Fuzzy Linear Programming (MOFLP) models, these models have been applied for maximization of the Net Benefits (NB), Crop production (CP), Employment Generation (EG) and Manure Utilization (MU) respectively. The significant increase in the value of level of satisfaction (λ) has been found from 0.58 to 0.65 by using the TPMOFLP approach as compare to that of MOFLP model based on maxmin approach. The two-phase approach solution provides NB = 1503.56 Million Rupees, CP = 335729.30 Tons, EG = 29.74 Million Man days and MU = 160233.70 Tons respectively. The proposed model will be helpful for the Decision Maker (DM) to take a decision under conflicting situation while planning for different conflicting objectives simultaneously and has potential to find out an integrated irrigation planning with prime consideration for economic, social and environmental issue. 展开更多
关键词 SUSTAINABLE IRRIGATION planNING Multi Objective Fuzzy Linear programMING Maxmin APPROACH TWO-PHASE APPROACH
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Stochastic Programming For Order Allocation And Production Planning
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作者 Phan Nguyen Ky Phuc 《Computer Systems Science & Engineering》 SCIE EI 2022年第1期75-85,共11页
Stochastic demand is an important factor that heavily affects production planning.It influences activities such as purchasing,manufacturing,and selling,and quick adaption is required.In production planning,for reasons... Stochastic demand is an important factor that heavily affects production planning.It influences activities such as purchasing,manufacturing,and selling,and quick adaption is required.In production planning,for reasons such as reducing costs and obtaining supplier discounts,many decisions must be made in the initial stage when demand has not been realized.The effects of non-optimal decisions will propagate to later stages,which can lead to losses due to overstocks or out-of-stocks.To find the optimal solutions for the initial and later stage regarding demand realization,this study proposes a stochastic two-stage linear program-ming model for a multi-supplier,multi-material,and multi-product purchasing and production planning process.The objective function is the expected total cost after two stages,and the results include detailed plans for purchasing and production in each demand scenario.Small-scale problems are solved through a deterministic equivalent transformation technique.To solve the problems in the large scale,an algorithm combining metaheuristic and sample average approximation is suggested.This algorithm can be implemented in parallel to utilize the power of the solver.The algorithm based on the observation that if the remaining quantity of materials and number of units of products at the end of the initial stage are given,then the problems of the first and second stages can be decomposed. 展开更多
关键词 Mixed integer programming two-stage stochastic programming production planning order allocation
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Family Planning Program in Guangxi
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《China Population Today》 1999年第Z2期22-24,共3页
关键词 Family planning program in Guangxi RATE FP OVER
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A Review of Quantitative Analysis (QA) in Production Planning Decisions Using the Linear Programming Model
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作者 Karibo Benaiah Bagshaw 《American Journal of Operations Research》 2019年第6期255-269,共15页
The purpose of this paper was to examine the role of quantitative analysis in production planning decisions. This draws from the observed imperatives of quantitative analysis in business decisions and its capacity for... The purpose of this paper was to examine the role of quantitative analysis in production planning decisions. This draws from the observed imperatives of quantitative analysis in business decisions and its capacity for predictability and enhanced decision making given the increasingly complex nature of the business environment. The paper therefore addressed the historical evolution of quantitative technique as an efficient and effective decision-making tool. The content of the paper addressed commonly applied quantitative technique in manufacturing firms today which is, linear programming and its subsequent impact on production planning decisions. The results based on a congruence of views revealed that the “best-fit” application of quantitative analysis models and tools can untangle the complexities of production and planning decision making process in order to achieve the organizational goal. This is, as literature also showed that there is obviously no consensus or integrated model that is capable of solving all managerial problem, different models such as the linear programming model have however been developed to cater for different problems as they arise. The workability or suitability of quantitative analysis is actually premised on its appropriate application. The paper recommends the application of quantitative analysis using linear programming in solving various resource allocation related issues in the primary production planning function of manufacturing firms. 展开更多
关键词 DECISION MAKING Linear programMING Production planNING QUANTITATIVE Analysis
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Using Quality of Care Indicators to AssessFamily Planning Program: Xuanwu,Nanjing
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作者 Zhou Wei 《China Population Today》 1999年第Z2期12-14,32,共4页
关键词 ICR Xuanwu Nanjing PSR KDR Using Quality of Care Indicators to AssessFamily planning program
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China's Biotech Achievements——Development of China's 863 Program in the Ninth Five-Year Plan Period
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《China's Foreign Trade》 2002年第6期44-45,共2页
Modern biotechnology booms in the molecular life science. It brings about a promising future for improving human health, foodstuff, environment and energy and is of significance to improve traditional agriculture, dru... Modern biotechnology booms in the molecular life science. It brings about a promising future for improving human health, foodstuff, environment and energy and is of significance to improve traditional agriculture, druamakins and other 展开更多
关键词 In China’s Biotech Achievements Development of China’s 863 program in the Ninth Five-Year plan Period gene
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China's Biotechnology Development Program during the Tenth Five-Year Plan Period (2001-2005)
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《China's Foreign Trade》 2002年第6期46-46,共1页
Bioengineering TechnoIogy(Ⅰ)1. Crop molecular marker-assisted selection and pyramiding breeding technology2. Super hybrid
关键词 high China’s Biotechnology Development program during the Tenth Five-Year plan Period
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Analysis of Citizen Participation in Urban Planning of Comala,Colima,Mexico-A Secondary Publication
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作者 Amallinaly GCárdenas Aguilar Peter Chung Alonso +2 位作者 Alicia Cuevas Muñiz Dora Correa Fuentes Ignacio Barajas Avalos 《Journal of World Architecture》 2024年第1期63-75,共13页
The objective of this study was to determine the degree of citizen participation in urban planning processes in the municipality of Comala,Colima,Mexico to have a broader vision of the citizens and the environment in ... The objective of this study was to determine the degree of citizen participation in urban planning processes in the municipality of Comala,Colima,Mexico to have a broader vision of the citizens and the environment in which they live.An instrument was designed specifically to perform this study and the instrument was validated by calculating Cronbach’s Alpha.The results showed that citizens were highly involved in issues concerning their urban environment,and the main problems of the public spaces were also identified. 展开更多
关键词 Citizen participation planNING Urban development program
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A Novel MILP Model Based on the Topology of a Network Graph for Process Planning in an Intelligent Manufacturing System 被引量:6
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作者 Qihao Liu Xinyu Li Liang Gao 《Engineering》 SCIE EI 2021年第6期807-817,共11页
Intelligent process planning(PP)is one of the most important components in an intelligent manufacturing system and acts as a bridge between product designing and practical manufacturing.PP is a nondeterministic polyno... Intelligent process planning(PP)is one of the most important components in an intelligent manufacturing system and acts as a bridge between product designing and practical manufacturing.PP is a nondeterministic polynomial-time(NP)-hard problem and,as existing mathematical models are not formulated in linear forms,they cannot be solved well to achieve exact solutions for PP problems.This paper proposes a novel mixed-integer linear programming(MILP)mathematical model by considering the network topology structure and the OR nodes that represent a type of OR logic inside the network.Precedence relationships between operations are discussed by raising three types of precedence relationship matrices.Furthermore,the proposed model can be programmed in commonly-used mathematical programming solvers,such as CPLEX,Gurobi,and so forth,to search for optimal solutions for most open problems.To verify the effectiveness and generality of the proposed model,five groups of numerical experiments are conducted on well-known benchmarks.The results show that the proposed model can solve PP problems effectively and can obtain better solutions than those obtained by the state-ofthe-art algorithms. 展开更多
关键词 Process planning NETWORK Mixed-integer linear programming CPLEX
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Energy-Optimal Braking Control Using a Double-Layer Scheme for Trajectory Planning and Tracking of Connected Electric Vehicles 被引量:7
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作者 Haoxuan Dong Weichao Zhuang +4 位作者 Guodong Yin Liwei Xu Yan Wang Fa’an Wang Yanbo Lu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第5期44-55,共12页
Most researches focus on the regenerative braking system design in vehicle components control and braking torque distribution,few combine the connected vehicle technologies into braking velocity planning.If the brakin... Most researches focus on the regenerative braking system design in vehicle components control and braking torque distribution,few combine the connected vehicle technologies into braking velocity planning.If the braking intention is accessed by the vehicle-to-everything communication,the electric vehicles(EVs)could plan the braking velocity for recovering more vehicle kinetic energy.Therefore,this paper presents an energy-optimal braking strategy(EOBS)to improve the energy efficiency of EVs with the consideration of shared braking intention.First,a double-layer control scheme is formulated.In the upper-layer,an energy-optimal braking problem with accessed braking intention is formulated and solved by the distance-based dynamic programming algorithm,which could derive the energy-optimal braking trajectory.In the lower-layer,the nonlinear time-varying vehicle longitudinal dynamics is transformed to the linear time-varying system,then an efficient model predictive controller is designed and solved by quadratic programming algorithm to track the original energy-optimal braking trajectory while ensuring braking comfort and safety.Several simulations are conducted by jointing MATLAB and CarSim,the results demonstrated the proposed EOBS achieves prominent regeneration energy improvement than the regular constant deceleration braking strategy.Finally,the energy-optimal braking mechanism of EVs is investigated based on the analysis of braking deceleration,battery charging power,and motor efficiency,which could be a guide to real-time control. 展开更多
关键词 Connected electric vehicles Energy optimization Velocity planning Regenerative braking Dynamic programming Model predictive control
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Evaluation of Breeding Programs Combining Genomic Information in Chinese Holstein 被引量:2
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作者 CHEN Jun WANG Ya-chun ZHANG Yi SUN Dong-xiao ZHANG Sheng-li ZHANG Yuan 《Agricultural Sciences in China》 CAS CSCD 2011年第12期1949-1957,共9页
Current study adopted gene flow theory and selection index method to compare the breeding efficiency of three breeding plans in the Chinese Holstein cattle using ZPLAN software. Simulated conventional progeny-testing ... Current study adopted gene flow theory and selection index method to compare the breeding efficiency of three breeding plans in the Chinese Holstein cattle using ZPLAN software. Simulated conventional progeny-testing program (PT) and young sire program (YS) were compared with breeding program using genomic selection (GS) taking parameters derived from Chinese Holstein breeding system. The results showed that, GS shortened generation interval by 1.5-2.2 years, and increased the genetic progress by 30-50%, comparing to PT and YS, respectively. Economic analysis showed that GS could obtain a higher breeding efficiency, being 119 and 97% higher than that of PT and YS, respectively; and GS was also powerful in improving functional traits with a low heritability. Main factors affecting breeding efficiency in GS were further discussed, including selection intensity, accuracy and the cost of SNP genotyping. Our finding provided references for future designing and implementing GS in Chinese dairy population. 展开更多
关键词 Chinese Holstein genomic selection progeny-testing program young sire program breeding plan
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