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一种分析Timed-Release公钥协议的扩展逻辑 被引量:5
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作者 范红 冯登国 《计算机学报》 EI CSCD 北大核心 2003年第7期831-836,共6页
在Coffey和Saidha提出的CS逻辑 (CS逻辑将时间与逻辑结构相结合 ,可用于形式化分析Timed release公钥协议的时间相关性秘密的安全性 )的基础上 ,提出了CS逻辑的扩展逻辑 ,它更好地反映了Timed release公钥协议的特性 ,并对一个协议实例... 在Coffey和Saidha提出的CS逻辑 (CS逻辑将时间与逻辑结构相结合 ,可用于形式化分析Timed release公钥协议的时间相关性秘密的安全性 )的基础上 ,提出了CS逻辑的扩展逻辑 ,它更好地反映了Timed release公钥协议的特性 ,并对一个协议实例进行了有效的形式化分析 . 展开更多
关键词 timed-release公钥协议 扩展逻辑 密钥 密码协议 形式化分析
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Acoustic emission characteristics and stress release rate of coal samples in different dynamic destruction time 被引量:3
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作者 Xiao Fukun Liu Gang +3 位作者 Zhang Ze Shen Zhiliang Zhang Fengrui Wang Yifei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期981-988,共8页
Considering the importance of the prediction of rock burst disasters, and in order to grasp the law of acoustic emission(AE) of coal samples in different dynamic destruction time, the SH-II AE monitoring system was ad... Considering the importance of the prediction of rock burst disasters, and in order to grasp the law of acoustic emission(AE) of coal samples in different dynamic destruction time, the SH-II AE monitoring system was adopted to monitor the failure process of coal samples. The study of the change rule of the AE numbers, energy, ‘b' value and spectrum in the micro crack propagation process of the coal samples shows that as dynamic damage time went by, AE presented high-energy counts and the accumulated counts increased during the compression phase. The AE energy and cumulative counts increased during the elastic stage. The AE blank area increased gradually and the blank lines were more and more obvious in the molding stage. The AE counts and energy showed a trend of decrease in the residual damage phase.AE ‘b' values gradually became sparse, and the large scale cracks percentage compared with micro cracks decreased and the degree of damage decreased. The AE frequency spectrum peak went from the residual damage phase to the molding phase, and finally it was nearly stable, besides the bandwidth of the main frequency is gradually narrowed. Also, the frequency peak changed from single peak frequency to bi-peak frequency and to the single peak frequency. Uniaxial compressive strength is more sensitive than the elastic modulus to dynamic damage time. 展开更多
关键词 Dynamic destruction time Acoustic emission Outburst-proneness Stress release rate
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Online scheduling of jobs with kind release times and deadlines on a single machine
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作者 LI Wen-jie MA Ran FENG Qi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第1期113-126,共14页
This paper studies online scheduling of jobs with kind release times on a single machine. Here "kind release time" means that in online setting, no jobs can be released when the machine is busy. Each job J h... This paper studies online scheduling of jobs with kind release times on a single machine. Here "kind release time" means that in online setting, no jobs can be released when the machine is busy. Each job J has a kind release time r(J) ≥ 0, a processing time p(J) > 0 and a deadline d(J) > 0. The goal is to determine a schedule which maximizes total processing time( p(J)E(J)) or total number( E(J)) of the accepted jobs. For the first objective function p(J)E(J), we first present a lower bound 2(1/2), and then provide an online algorithm LEJ with a competitive ratio of 3. This is the first deterministic algorithm for the problem with a constant competitive ratio. When p(J) ∈ {1, k}, k > 1 is a real number, we first present a lower bound min{(1 + k)/k, 2 k/(1 + k)}, and then we show that LEJ has a competitive ratio of1 + k/k. In particular, when all the k length jobs have tight deadlines, we first present a lower bound max{4/(2 + k), 1}(for p(J)E(J)) and 4/3(for E(J)). Then we prove that LEJ is k/k-competitive for p(J)E(J) and we provide an online algorithm H with a competitive ratio of 2 k/( k + 1) for the second objective function E(J). 展开更多
关键词 SCHEDULING ONLINE algorithm KIND release time DEADLINE
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Parallel Machine Problems with a Single Server and Release Times
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作者 SHILing 《Geo-Spatial Information Science》 2005年第2期148-151,共4页
Parallel machine problems with a single server and release times are generalizations of classical parallel machine problems. Before processing, each job must be loaded on a machine, which takes a certain release times... Parallel machine problems with a single server and release times are generalizations of classical parallel machine problems. Before processing, each job must be loaded on a machine, which takes a certain release times and a certain setup times. All these setups have to be done by a single server, which can handle at most one job at a time. In this paper, we continue studying the complexity result for parallel machine problem with a single and release times. New complexity results are derived for special cases. 展开更多
关键词 parallel machine problem single server release time COMPLEXITY
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Design of Atomic Time Scale Release System for Multiple Laboratories
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作者 ZHU Jiangmiao ZHAO Weibo +2 位作者 GAO Yuan WANG Xing GAO Xiuna 《Instrumentation》 2020年第1期24-32,共9页
The atomic time scale release system for multiple laboratories is completed by modular design according to the atomic clock data provided by eight domestic punctual laboratories.The system includes the three modules,t... The atomic time scale release system for multiple laboratories is completed by modular design according to the atomic clock data provided by eight domestic punctual laboratories.The system includes the three modules,the processing of atomic clock data,the calculation of atomic time scale and the release of atomic time scale data,using MATLAB for data processing and time scale calculation,and using GUI for data visualization design.The system has clear process of the algorithm,simple function modules and friendly human-machine interface.The operation results of actual data show that the time difference between the integrated atomic time scale of the system and UTC is better than±10ns,and the content of data release can meet the needs of the scientific research in related fields in China. 展开更多
关键词 Atomic Clock Weight Distribution Atomic time Scale Data release
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Rationale of Timed-Release Analysis and the Improvement of Flotation Experiment
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作者 刘炯天 周振英 +2 位作者 李备备 沈正义 王进才 《International Journal of Mining Science and Technology》 SCIE EI 1998年第2期113-117,共5页
The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward... The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward a proposal to improve this test method by adding a new test step of scavenging flotation and using optimum test conditions varied with different fine coals instead of the given ones settled by the TRA norm. Comparison between test results of the two methods of TRA shows that the improved method is very good. 展开更多
关键词 laboratory COAL FLOTATION TEST Method timed-release ANALYSIS optimization of TEST conditions optimum results of COAL FLOTATION
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Study the effect of formulation variables in the development of timed-release press-coated tablets by Taguchi design
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作者 Chikkanna Narendra Mayasandra SrinavasaIyengar Srinath 《Natural Science》 2010年第4期379-387,共9页
In this investigation, the effect of formulation variables on the release properties of timed- release press-coated tablets was studied using the Taguchi method of experimental design. Formulations were prepared based... In this investigation, the effect of formulation variables on the release properties of timed- release press-coated tablets was studied using the Taguchi method of experimental design. Formulations were prepared based on Taguchi orthogonal array design with different types of hydrophilic polymers (X1), varying hydrophilic polymer/ethyl cellulose ratio (X2), and addition of magnesium stearate (X3) as independent variables. The design was quantitatively evalu-ated by best fit mathematical model. The results from the statistical analysis revealed that factor X1, X3 and interaction factors between X1X2 and X1X3 were found to be significant on the re-sponse lag time (Y1), where as only factor X1 was found to be significant on the response percent drug release at 8 hrs (Y2). A numerical optimization technique by desirability function was used to optimize the response variables, each having a different target. Based on the re-sults of optimization study, HPC was identified as the most suitable hydrophilic polymer and incorporation of hydrophobic agent magnesium stearate, could significantly improve the lag time of the timed-release press-coated tablet. 展开更多
关键词 Press-Coated TABLET Taguchi Design HYDROPHILIC Polymers timed-release Hydrophobic Agents
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Decisive Factors of Conidia Release of Botryosphaeria berengeriana during Growing Season 被引量:1
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作者 王晔 胡同乐 曹克强 《Plant Diseases and Pests》 CAS 2010年第5期34-37,共4页
[ Objective ] The study aimed to explore the release conditions for the conidia of Botryosphaena berengeriana and understand the release dynamic of conidia. [Method] The systematical survey on the release conditions f... [ Objective ] The study aimed to explore the release conditions for the conidia of Botryosphaena berengeriana and understand the release dynamic of conidia. [Method] The systematical survey on the release conditions for the conidia of B. berengeriana were conducted in two growing seasons in 2008 and 2009, combined with the collection of meteorological data around conidia release period, the weather conditions causing large amount release of B. berengedana were analyzed. [ Result] During a growing season, the conidia of pathogen appeared several large release peaks. Under the suitable temperature, when the precipitation lasted for 4 h, the conidia of B. berengeriana began to release with large amount, the amount of conidia reached the peak after release and trended to be stable during 4 - 12 h, which significantly reduced after 24 h, tended to dis- appear after 36 h, and completely disappeared after 72 h. [Conclusion] The dominant factor affecting B. berengeriana conidia release in large a- mount was precipitation, while the lasting time of precipitation played a decisive role. 展开更多
关键词 Botryosphaeria berengeriana de Not. f. sp. piricola Conidia release Precipitation lasting time Decisive factor
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Solving Multitrip Pickup and Delivery Problem With Time Windows and Manpower Planning Using Multiobjective Algorithms 被引量:6
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作者 Jiahai Wang Yuyan Sun +1 位作者 Zizhen Zhang Shangce Gao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第4期1134-1153,共20页
The multitrip pickup and delivery problem with time windows and manpower planning(MTPDPTW-MP)determines a set of ambulance routes and finds staff assignment for a hospital. It involves different stakeholders with dive... The multitrip pickup and delivery problem with time windows and manpower planning(MTPDPTW-MP)determines a set of ambulance routes and finds staff assignment for a hospital. It involves different stakeholders with diverse interests and objectives. This study firstly introduces a multiobjective MTPDPTW-MP(MO-MTPDPTWMP) with three objectives to better describe the real-world scenario. A multiobjective iterated local search algorithm with adaptive neighborhood selection(MOILS-ANS) is proposed to solve the problem. MOILS-ANS can generate a diverse set of alternative solutions for decision makers to meet their requirements. To better explore the search space, problem-specific neighborhood structures and an adaptive neighborhood selection strategy are carefully designed in MOILS-ANS. Experimental results show that the proposed MOILS-ANS significantly outperforms the other two multiobjective algorithms. Besides, the nature of objective functions and the properties of the problem are analyzed. Finally, the proposed MOILS-ANS is compared with the previous single-objective algorithm and the benefits of multiobjective optimization are discussed. 展开更多
关键词 Adaptive neighborhood selection manpower planning multiobjective optimization multitrip pickup and delivery problem with time windows
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Design and preparation of press-coated tablets for pulsed release of verapamil
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作者 邹豪 马伯良 蒋雪涛 《Journal of Medical Colleges of PLA(China)》 CAS 1999年第4期266-269,共4页
Objective: To achieve pulsed release system of verapamil on the basis of circadian rhythms of hypertensive patients. Methods: Factors affecting the lag time of the system were tested. Three swelling disintegrates (L-H... Objective: To achieve pulsed release system of verapamil on the basis of circadian rhythms of hypertensive patients. Methods: Factors affecting the lag time of the system were tested. Three swelling disintegrates (L-HPC,CMS-Na, CMC-Ca) of different contents were used- Various compositions of out shell were tested throughthe uniform design and dealt with multipleregression. Two basic formulations whose lag time is 3 and 5 h were decided- Results: The lag time 5 h formulation: CMS-Na was the preferable disintegrate with content 15 mg/tablet,out shell composition were chosen as PEG 6000 110 mg, HCO 105 mg, EVA 25 mg each tablet. Hardness 5 kg/cm2. Conclusion: A new press-coated tablets for the pulsed release of drug after a programmable period of time isachieved in the in vitro dissolution test. 展开更多
关键词 VERAPAMIL PULSED release system CIRCADIAN RHYTHMS lag time
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Reliability Growth Modeling and Optimal Release Policy Under Fuzzy Environment of an N-version Programming System Incorporating the Effect of Fault Removal Efficiency
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作者 P.K.Kapur Anshu Gupta P.C.Jha 《International Journal of Automation and computing》 EI 2007年第4期369-379,共11页
Failure of a safety critical system can lead to big losses. Very high software reliability is required for automating the working of systems such as aircraft controller and nuclear reactor controller software systems.... Failure of a safety critical system can lead to big losses. Very high software reliability is required for automating the working of systems such as aircraft controller and nuclear reactor controller software systems. Fault-tolerant softwares are used to increase the overall reliability of software systems. Fault tolerance is achieved using the fault-tolerant schemes such as fault recovery (recovery block scheme), fault masking (N-version programming (NVP)) or a combination of both (Hybrid scheme). These softwares incorporate the ability of system survival even on a failure. Many researchers in the field of software engineering have done excellent work to study the reliability of fault-tolerant systems. Most of them consider the stable system reliability. Few attempts have been made in reliability modeling to study the reliability growth for an NVP system. Recently, a model was proposed to analyze the reliability growth of an NVP system incorporating the effect of fault removal efficiency. In this model, a proportion of the number of failures is assumed to be a measure of fault generation while an appropriate measure of fault generation should be the proportion of faults removed. In this paper, we first propose a testing efficiency model incorporating the effect of imperfect fault debugging and error generation. Using this model, a software reliability growth model (SRGM) is developed to model the reliability growth of an NVP system. The proposed model is useful for practical applications and can provide the measures of debugging effectiveness and additional workload or skilled professional required. It is very important for a developer to determine the optimal release time of the software to improve its performance in terms of competition and cost. In this paper, we also formulate the optimal software release time problem for a 3VP system under fuzzy environment and discuss a the fuzzy optimization technique for solving the problem with a numerical illustration. 展开更多
关键词 Fault tolerant software reliability growth model release time fuzzy optimization.
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Physicochemical Properties and Control Release of Aloe Vera (Aloe barbadensis Miller) Bioactive Loaded Poly (Lactic Co-Glycolide Acid) Synthesized Nanoparticles
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作者 Lamin S. Kassama Jawadul Misir 《Advances in Chemical Engineering and Science》 2017年第4期333-348,共16页
Nano-encapsulation is a platform which offers a promising application for control release and the delivery of drugs in pharmaceuticals and antioxidant/ antimicrobial in food systems. Poly (lactic-co-glycolide acid) (P... Nano-encapsulation is a platform which offers a promising application for control release and the delivery of drugs in pharmaceuticals and antioxidant/ antimicrobial in food systems. Poly (lactic-co-glycolide acid) (PLGA) is a biodegradable and biocompatible co-polymer of lactic acid and glycolic acid which is used for synthesizing food based polymeric nanoparticles (NP). The aim of this study was to evaluate the morphological and physicochemical properties and the controlled release of bioactive components derived from Aloe vera gel loaded PLGA NP. The results shows the mean hydrodynamic diameter of the unloaded NP is 103 nm which is significantly (p < 0.01) smaller than the loaded freeze dried powered gel (FDG) (147 nm) and liquid gel (LG) (221 nm) and the particle size distribution given by the Poly-dispersity Index were 0.2, 0.2 and 0.3, respectively. The zeta potential for unloaded, FDG and LG NP were ±60, ±28 and ±22 mV, respectively, hence were electrokinetically stable NP. No significant (p > 0.05) inhibition of the antioxidant potential was observed with loaded NP. The entrapment efficiency for the FDG synthesized was 87%, and the burst effect was observed after 4 h as a result of the encapsulation effect. The release kinetics of bioactive is govern by the combination of mass diffusion and capillary action. 展开更多
关键词 NANOENCAPSULATION PLGA ALOE VERA Gel Size Distribution time release Kinetics & Antioxidant
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Five National Standards on Electric Vehicles Released
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《China Standardization》 2016年第3期6-7,共2页
Five Chinese national standards on electrically propelled road vehicles,leaded and drafted by CRRC Times Electric Vehicle Co.,Ltd.,were offi cially released recently.The standards include 3 parts of GB/T 18384 on the ... Five Chinese national standards on electrically propelled road vehicles,leaded and drafted by CRRC Times Electric Vehicle Co.,Ltd.,were offi cially released recently.The standards include 3 parts of GB/T 18384 on the safety specifi cations for electrically propelled road vehicles,that is GB/T 18384.1-2015,GB/T 18384.2-2015and GB/T 18384.3-2015,and 2 parts of GB/T 18488 on drive motor system for electric vehicles,including GB/T 18488.1-2015 and GB/T 18488.2-2015. 展开更多
关键词 electrically releaseD timeS providing downs GUARD PERSONNEL BREAK
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Mating behavior and sex pheromone release rhythm of Holotrichia parallela(Coleoptera: Melolonthidae)
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作者 Zhen Yang Dan Liang +6 位作者 Qian Ju Quansen Chen Xiao Li Xiaojing Jiang Maohua Chen Weiqiang Yang Mingjing Qu 《Oil Crop Science》 2019年第1期10-16,共7页
Mating behavior and sex pheromone release rhythm of Holotrichia parallela was studied in this research. The maximum mating times were 3 for female and 4 for male. Average mating times were 1.06 for female and 0.91 for... Mating behavior and sex pheromone release rhythm of Holotrichia parallela was studied in this research. The maximum mating times were 3 for female and 4 for male. Average mating times were 1.06 for female and 0.91 for male. L-isoleucine methyl ester(LIME), a major component of pheromone, increased gradually from 14:00 and peaked at 19:00, then dropped sharply at 20:00 and remained low at 24:00.(R)-(-)-linalool(referred as linalool below) maintained similar levels throughout the study period. Calling and mating activity significantly decreased LIME titer, but not linalool. Analyses of 11 samples collected during calling days(20 d-70 d) revealed that LIME production was affected by female age. LIME titers increased from 20 d to 45 d, and decreased from 45 d to 70 d. While linalool titers remained at similar levels at all sampling dates. The highest ratio between LIME and linalool was 12 and the lowest was 4. Field tests confirmed that the most attractive ratios of LIME: linalool in early season(June 1 to 20) and late season(August 1 to 20) were 6:1, while in the most serious injury stage(June 20 to August 1) was 12:1. This is the first report about circadian rhythmicity of sex pheromone in Holotrichia parallela, which provides a basis for controlling it in field. 展开更多
关键词 PHEROMONE release RHYTHM MATING times PHEROMONE lure field test
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Self-Reported Adherence after Overnight Switching from Immediate- to Extended-Release Pramipexole in Parkinson’s Disease
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作者 Mutsumi Iijima Mikio Osawa +2 位作者 Kenji Maruyama Shinichiro Uchiyama Kazuo Kitagawa 《Advances in Parkinson's Disease》 2015年第1期13-19,共7页
Background: Drug adherence decreased in patients with Parkinson’ s disease (PD) because of taking many different types of drugs. We evaluated drug adherence after switching from immediate-release (IR) to once-daily e... Background: Drug adherence decreased in patients with Parkinson’ s disease (PD) because of taking many different types of drugs. We evaluated drug adherence after switching from immediate-release (IR) to once-daily extended-release (ER) pramipexole (PPX) in PD. Methods: This study included 35 PD patients (20 men, 15 women);10 were taking oral PPX alone, and 25 were also using another anti-PD drug. PPX-IR was switched overnight to PPX-ER without gradual tapering. One month after switching, improvement in timing adherence and reduction in medication burden were evaluated by a questionnaire using a visual analog scale (VAS) (0: No change;10: Better). Motor function was assessed using part III of the Unified Parkinson’s Disease Rating Scale (UPDRS). Results: The VAS score for improvement in timing adherence was 8.1 ± 0.5 (mean ± standard error), and that for reduction in medication burden was 7.3 ± 0.6. There was a significant negative correlation (ρ = -0.43, p = 0.01) between the VAS score and number of types of medications. The UPDRS part III score improved significantly after switching 展开更多
关键词 Parkinson’s Disease Timing ADHERENCE PRAMIPEXOLE EXTENDED-release Immediate-release Motor Function
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面向复杂物流配送场景的车辆路径规划多任务辅助进化算法 被引量:1
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作者 李坚强 蔡俊创 +2 位作者 孙涛 朱庆灵 林秋镇 《自动化学报》 EI CAS CSCD 北大核心 2024年第3期544-559,共16页
在现代社会中,复杂物流配送场景的车辆路径规划问题(Vehicle routing problem,VRP)一般带有时间窗约束且需要提供同时取送货的服务.这种复杂物流配送场景的车辆路径规划问题是NP-难问题.当其规模逐渐增大时,一般的数学规划方法难以求解... 在现代社会中,复杂物流配送场景的车辆路径规划问题(Vehicle routing problem,VRP)一般带有时间窗约束且需要提供同时取送货的服务.这种复杂物流配送场景的车辆路径规划问题是NP-难问题.当其规模逐渐增大时,一般的数学规划方法难以求解,通常使用启发式方法在限定时间内求得较优解.然而,传统的启发式方法从原大规模问题直接开始搜索,无法利用先前相关的优化知识,导致收敛速度较慢.因此,提出面向复杂物流配送场景的车辆路径规划多任务辅助进化算法(Multitask-based assisted evolutionary algorithm,MBEA),通过使用迁移优化方法加快算法收敛速度,其主要思想是通过构造多个简单且相似的子任务用于辅助优化原大规模问题.首先从原大规模问题中随机选择一部分客户订单用于构建多个不同的相似优化子任务,然后使用进化多任务(Evolutional multitasking,EMT)方法用于生成原大规模问题和优化子任务的候选解.由于优化子任务相对简单且与原大规模问题相似,其搜索得到的路径特征可以通过任务之间的知识迁移辅助优化原大规模问题,从而加快其求解速度.最后,提出的算法在京东物流公司快递取送货数据集上进行验证,其路径规划效果优于当前最新提出的路径规划算法. 展开更多
关键词 车辆路径规划问题 时间窗约束 同时取送货 进化算法 迁移优化
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带时间窗的时间依赖型同时取送货车辆路径问题研究
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作者 何美玲 杨梅 +1 位作者 韩珣 武晓晖 《交通运输系统工程与信息》 EI CSCD 北大核心 2024年第4期231-242,262,共13页
针对带时间窗的时间依赖型同时取送货车辆路径问题(Time Dependent Vehicle Routing Problem with Simultaneous Pickup-Delivery and Time Windows,TDVRPSPDTW),本文建立以车辆固定成本、驾驶员成本、燃油消耗及碳排放成本之和为优化... 针对带时间窗的时间依赖型同时取送货车辆路径问题(Time Dependent Vehicle Routing Problem with Simultaneous Pickup-Delivery and Time Windows,TDVRPSPDTW),本文建立以车辆固定成本、驾驶员成本、燃油消耗及碳排放成本之和为优化目标的数学模型;并在传统蚁群算法的基础上,利用节约启发式构造初始解初始化信息素,改进状态转移规则,引入局部搜索策略,提出一种带自适应大邻域搜索的混合蚁群算法(Ant Colony Optimization with Adaptive Large Neighborhood Search,ACO-ALNS)进行求解;最后,分别选取基准问题算例和改编生成TDVRPSPDTW算例进行实验。实验结果表明:本文提出的ACO-ALNS算法可有效解决TDVRPSPDTW的基准问题;相较于模拟退火算法和带局部搜索的蚁群算法,本文算法求解得到的总配送成本最优值平均分别改善7.56%和2.90%;另外,相比于仅考虑碳排放或配送时间的模型,本文所构建的模型综合多种因素,总配送成本平均分别降低4.38%和3.18%,可有效提高物流企业的经济效益。 展开更多
关键词 物流工程 同时取送货车辆路径问题 蚁群算法 时间依赖 时间窗
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控释掺混肥料一次性基施对热带地区水稻产量及氮肥利用效率的影响
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作者 杨红竹 黄艳艳 +3 位作者 刘海林 林清火 茶正早 罗微 《福建农业学报》 CAS CSCD 北大核心 2024年第7期766-774,共9页
【目的】探究控释掺混肥及减氮处理对热带地区水稻产量及氮肥利用效率的影响,以期促进控释掺混肥料在热带地区水稻栽培中的科学施用及推广应用。【方法】以控释掺混肥料为试验材料,在海南省屯昌县枫木镇和儋州市东成镇开展大田试验,设... 【目的】探究控释掺混肥及减氮处理对热带地区水稻产量及氮肥利用效率的影响,以期促进控释掺混肥料在热带地区水稻栽培中的科学施用及推广应用。【方法】以控释掺混肥料为试验材料,在海南省屯昌县枫木镇和儋州市东成镇开展大田试验,设置常规施肥(分3次施肥)、控释掺混肥料一次性基施及其减氮10%和减氮20%处理,测定双季稻产量、氮素吸收及氮肥利用效率。【结果】等氮条件下,控释掺混肥料一次性基施能够促进水稻氮素吸收、干物质累积,提高水稻产量和氮肥利用效率;与常规分次施肥相比,水稻产量提高7.43%~22.84%,地上部干物质累积量提高8.22%~22.39%,氮素累积量提高12.19%~32.06%,氮肥利用率提高31.67%~75.65%,且均差异显著(除东成早稻产量外)。而在减氮10%~20%条件下,控释掺混肥一次性基施也能提高或不显著降低水稻产量、干物质累积量和氮素累积量,对氮肥利用率也具有一定提升效果。【结论】控释掺混肥一次性基施可提高水稻产量及肥料氮肥利用率,减氮10%~20%仍能获得较高产量,是热带地区水稻轻简化施肥和减氮增效的有效途径。 展开更多
关键词 控释掺混肥料 一次性施用 水稻 热带地区 产量
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多中心半开放式同时送取货的车辆路径问题研究
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作者 陈荣虎 张建宏 徐祯 《哈尔滨商业大学学报(自然科学版)》 CAS 2024年第1期32-38,共7页
研究了带软时间窗约束的多配送中心半开放式同时送取货的车辆路径问题,所有客户点均存在送取两种需求,并采用同一辆车同时提供送取服务.车辆服务完路线上所有客户点后,不一定返回起始配送中心,可就近返回任意配送中心.在此条件下,构建... 研究了带软时间窗约束的多配送中心半开放式同时送取货的车辆路径问题,所有客户点均存在送取两种需求,并采用同一辆车同时提供送取服务.车辆服务完路线上所有客户点后,不一定返回起始配送中心,可就近返回任意配送中心.在此条件下,构建了以车辆运输成本、车辆租赁成本、时间窗惩罚成本等总和最小为目标的优化模型.根据问题特征,设计了自适应精英遗传算法对该问题进行求解,引入自适应机制,根据个体的适应度动态地调节交叉和变异概率,采用精英保留策略将优秀个体进行遗传保留,不仅增强了算法的全局优化能力,还均衡了算法的局部搜索能力.通过案例仿真,验证了模型和算法的可行性和有效性.研究成果丰富了车辆路径问题的相关研究,为物流企业提供了一种决策参考. 展开更多
关键词 车辆路径问题 软时间窗 多中心半开放式 同时送取货 自适应精英遗传算法
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DCS算法求解带软时间窗的送取货一体化VRP
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作者 周明龙 《淮北师范大学学报(自然科学版)》 CAS 2024年第2期56-62,共7页
为求解带软时间窗的送取货一体化车辆路径问题,提出一种离散布谷鸟(DCS)搜索算法。该算法在基本布谷鸟搜索算法基础之上,对莱维飞行获取新鸟巢和以一定概率抛弃鸟巢的迭代公式进行重新定义;同时设计客户序列和车辆序列双倍体鸟巢,并对... 为求解带软时间窗的送取货一体化车辆路径问题,提出一种离散布谷鸟(DCS)搜索算法。该算法在基本布谷鸟搜索算法基础之上,对莱维飞行获取新鸟巢和以一定概率抛弃鸟巢的迭代公式进行重新定义;同时设计客户序列和车辆序列双倍体鸟巢,并对客户序列采用交换、逆序、插入操作和对每辆车的访问路线采用2-Opt操作。通过5个算例的仿真实验和相关文献比较,结果表明所提DCS算法行之有效。 展开更多
关键词 车辆路径问题 同时送取货 软时间窗 布谷鸟搜索算法
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