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A Review of On-Line Machine Scheduling:Algorithms and Competitiveness 被引量:11
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作者 陈礴 《数学理论与应用》 1999年第3期1-15,共15页
在过去的十年里,在线算法的研究吸引了广泛的兴趣.本文对在排序和时间表问题中的各种有效的在线算法以及它们的竞争度作一综述.
关键词 排序 时间表 在线算法 竞争度
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Line-feature-based SLAM Algorithm 被引量:6
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作者 HAN Rui LI Wen-Feng 《自动化学报》 EI CSCD 北大核心 2006年第1期43-46,共4页
A line-feature based SLAM algorithm is presented in this paper to resolve the conflict between the requirements of computational complexity and information-richness within the point-feature based SLAM algorithm, All o... A line-feature based SLAM algorithm is presented in this paper to resolve the conflict between the requirements of computational complexity and information-richness within the point-feature based SLAM algorithm, All operations required for building and maintaining the map, such as model-setting, data association, and state-updating, are described and formulated. This approach has been programmed and successfully tested in the simulation work, and results are shown at the end of this paper. 展开更多
关键词 线性特征 SLAM算法 复杂度 数据关联
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Extraction of Laser Stripe Center Line Based on Genetic Algorithm and NURBS Interpolation 被引量:2
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作者 朱文娟 焦开河 +1 位作者 徐春广 肖定国 《Journal of Beijing Institute of Technology》 EI CAS 2008年第2期143-147,共5页
To improve the measurement accuracy of structured laser for inner surface dimensions of a deep hole, a new method to extract the laser stripe center line is proposed. An improved adaptive genetic algorithm that can co... To improve the measurement accuracy of structured laser for inner surface dimensions of a deep hole, a new method to extract the laser stripe center line is proposed. An improved adaptive genetic algorithm that can converge rapidly and search the global optimum is used to determine the threshold for the laser stripe segmentation. And then NURBS interpolation which has a good local control capability is adopted to extract the laser stripe center line. Experiments show that the extracted laser stripe center line is stable and the diameter of the deep hole can be measured accurately. 展开更多
关键词 structured laser center line adaptive genetic algorithm NURBS interpolation
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The Line Clipping Algorithm Basing on Affine Transformation 被引量:1
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作者 Wenjun Huang 《Intelligent Information Management》 2010年第6期380-385,共6页
A new algorithm for clipping line segments by a rectangular window on rectangular coordinate system is presented in this paper. The algorithm is very different to the other line clipping algorithms. For the line segme... A new algorithm for clipping line segments by a rectangular window on rectangular coordinate system is presented in this paper. The algorithm is very different to the other line clipping algorithms. For the line segments that cannot be identified as completely inside or outside the window by simple testings, this algorithm applies affine transformations (the shearing transformations) to the line segments and the window, and changes the slopes of the line segments and the shape of the window. Thus, it is clear for the line segment to be outside or inside of the window. If the line segments intersect the window, the algorithm immediately (no solving equations) gets the intersection points. Having applied the inverse transformations to the intersection points, the algorithm has the final results. The algorithm is successful to avoid the complex classifications and computations. Besides, the algorithm is effective to simplify the processes of finding the intersection points. Comparing to some classical algorithms, the algorithm of this paper is faster for clipping line segments and more efficient for calculations. 展开更多
关键词 COMPUTER GRAPHICS line CLIPPING algorithm AFFINE TRANSFORMATION
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RECONFIGURABLE PRODUCTION LINE MODELING AND SCHEDULING USING PETRI NETS AND GENETIC ALGORITHM 被引量:8
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作者 XIE Nan LI Aiping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第3期362-367,共6页
In response to the production capacity and functionality variations, a genetic algorithm (GA) embedded with deterministic timed Petri nets(DTPN) for reconfigurable production line(RPL) is proposed to solve its s... In response to the production capacity and functionality variations, a genetic algorithm (GA) embedded with deterministic timed Petri nets(DTPN) for reconfigurable production line(RPL) is proposed to solve its scheduling problem. The basic DTPN modules are presented to model the corresponding variable structures in RPL, and then the scheduling model of the whole RPL is constructed. And in the scheduling algorithm, firing sequences of the Petri nets model are used as chromosomes, thus the selection, crossover, and mutation operator do not deal with the elements in the problem space, but the elements of Petri nets model. Accordingly, all the algorithms for GA operations embedded with Petri nets model are proposed. Moreover, the new weighted single-objective optimization based on reconfiguration cost and E/T is used. The results of a DC motor RPL scheduling suggest that the presented DTPN-GA scheduling algorithm has a significant impact on RPL scheduling, and provide obvious improvements over the conventional scheduling method in practice that meets duedate, minimizes reconfiguration cost, and enhances cost effectivity. 展开更多
关键词 Reconfigurable production line Deterministic timed Petri nets (DTPN) Modeling Scheduling Genetic algorithm(GA)
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Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms 被引量:6
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作者 杨彪 梁贵安 +5 位作者 彭金辉 郭胜惠 李玮 张世敏 李英伟 白松 《Journal of Central South University》 SCIE EI CAS 2013年第10期2685-2692,共8页
The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and wi... The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design. 展开更多
关键词 industrial microwave DRYING ROTARY device SELF-ADAPTIVE PID controller genetic algorithm ON-line tuning SELENIUM-ENRICHED SLAG
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Genetic Algorithm for Concurrent Balancing of Mixed-Model Assembly Lines with Original Task Times of Models 被引量:1
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作者 Panneerselvam Sivasankaran Peer Mohamed Shahabudeen 《Intelligent Information Management》 2013年第3期84-92,共9页
The growing global competition compels manufacturing organizations to engage themselves in all productivity improvement activities. In this direction, the consideration of mixed-model assembly line balancing problem a... The growing global competition compels manufacturing organizations to engage themselves in all productivity improvement activities. In this direction, the consideration of mixed-model assembly line balancing problem and implementing in industries plays a major role in improving organizational productivity. In this paper, the mixed model assembly line balancing problem with deterministic task times is considered. The authors made an attempt to develop a genetic algorithm for realistic design of the mixed-model assembly line balancing problem. The design is made using the originnal task times of the models, which is a realistic approach. Then, it is compared with the generally perceived design of the mixed-model assembly line balancing problem. 展开更多
关键词 Assembly line Balancing Cycle Time GENETIC algorithm CROSSOVER Operation Mixed-Model
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Sequencing of Mixed Model Assembly Lines Based on Improved Shuffled Frog Leaping Algorithm 被引量:1
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作者 ZHAO Xiaoqiang JI Shurong 《Journal of Donghua University(English Edition)》 EI CAS 2018年第2期154-159,共6页
Shuffled frog leaping algorithm( SFLA) was used to solve multi-objective sequencing problem of mixed model assembly line( MMAL). Local convergence can be avoided and optimal solution can be obtained to a certain exten... Shuffled frog leaping algorithm( SFLA) was used to solve multi-objective sequencing problem of mixed model assembly line( MMAL). Local convergence can be avoided and optimal solution can be obtained to a certain extent. However,the multi-objective sequencing problem of MMAL is an non-deterministic polynomial hard( NP-hard) problem and the shortcomings are slow convergence rate and low precision. To solve the shortcomings for optimization objectives of minimizing total utility time and keeping average consumption rate of parts, a chaos differential evolution SFLA( CDESFLA) is proposed in this study. Because SFLA is easy to fall into local optimum,the evolution operator of differential evolution algorithms is introduced in SFLA as a local search strategy,and differential mutation operator is introduced in chaotic sequence to prevent premature convergence. The examples show that the proposed CDESFLA is better for convergence accuracy than SFLA,genetic algorithm( GA) and particle swarm optimization( PSO) 展开更多
关键词 MIXED model ASSEMBLY line (MMAL) SEQUENCING shuffledfrog leaping algorithm (SFLA) CHAOS optimization differentialevolution algorithm
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An Improved Line Search and Trust Region Algorithm 被引量:1
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作者 Qinghua Zhou Yarui Zhang Xiaoli Zhang 《Journal of Software Engineering and Applications》 2013年第5期49-52,共4页
In this paper, we present a new line search and trust region algorithm for unconstrained optimization problems. The trust region center locates at somewhere in the negative gradient direction with the current best ite... In this paper, we present a new line search and trust region algorithm for unconstrained optimization problems. The trust region center locates at somewhere in the negative gradient direction with the current best iterative point being on the boundary. By doing these, the trust region subproblems are constructed at a new way different with the traditional ones. Then, we test the efficiency of the new line search and trust region algorithm on some standard benchmarking. The computational results reveal that, for most test problems, the number of function and gradient calculations are reduced significantly. 展开更多
关键词 TRUST REGION algorithmS TRUST REGION Subproblem line SEARCH UNCONSTRAINED Optimization
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Assembly Line Balancing Based on Double Chromosome Genetic Algorithm
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作者 刘俨后 左敦稳 张丹 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第6期622-628,共7页
Aiming at assembly line balancing problem,a double chromosome genetic algorithm(DCGA)is proposed to avoid trapping in local optimum,which is a disadvantage of standard genetic algorithm(SGA).In this algorithm,there ar... Aiming at assembly line balancing problem,a double chromosome genetic algorithm(DCGA)is proposed to avoid trapping in local optimum,which is a disadvantage of standard genetic algorithm(SGA).In this algorithm,there are two chromosomes of each individual,and the better one,regarded as dominant chromosome,determines the fitness.Dominant chromosome keeps excellent gene segments to speed up the convergence,and recessive chromosome maintains population diversity to get better global search ability to avoid local optimal solution.When the amounts of chromosomes are equal,the population size of DCGA is half that of SGA,which significantly reduces evolutionary time.Finally,the effectiveness is verified by experiments. 展开更多
关键词 double chromosome genetic algorithm assembly line balancing mathematical model global optimum
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Effective Hybrid Teaching-learning-based Optimization Algorithm for Balancing Two-sided Assembly Lines with Multiple Constraints 被引量:8
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作者 TANG Qiuhua LI Zixiang +2 位作者 ZHANG Liping FLOUDAS C A CAO Xiaojun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期1067-1079,共13页
Due to the NP-hardness of the two-sided assembly line balancing (TALB) problem, multiple constraints existing in real applications are less studied, especially when one task is involved with several constraints. In ... Due to the NP-hardness of the two-sided assembly line balancing (TALB) problem, multiple constraints existing in real applications are less studied, especially when one task is involved with several constraints. In this paper, an effective hybrid algorithm is proposed to address the TALB problem with multiple constraints (TALB-MC). Considering the discrete attribute of TALB-MC and the continuous attribute of the standard teaching-learning-based optimization (TLBO) algorithm, the random-keys method is hired in task permutation representation, for the purpose of bridging the gap between them. Subsequently, a special mechanism for handling multiple constraints is developed. In the mechanism, the directions constraint of each task is ensured by the direction check and adjustment. The zoning constraints and the synchronism constraints are satisfied by teasing out the hidden correlations among constraints. The positional constraint is allowed to be violated to some extent in decoding and punished in cost fimction. Finally, with the TLBO seeking for the global optimum, the variable neighborhood search (VNS) is further hybridized to extend the local search space. The experimental results show that the proposed hybrid algorithm outperforms the late acceptance hill-climbing algorithm (LAHC) for TALB-MC in most cases, especially for large-size problems with multiple constraints, and demonstrates well balance between the exploration and the exploitation. This research proposes an effective and efficient algorithm for solving TALB-MC problem by hybridizing the TLBO and VNS. 展开更多
关键词 two-sided assembly line balancing teaching-learning-based optimization algorithm variable neighborhood search positional constraints zoning constraints synchronism constraints
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Ethics Lines and Machine Learning: A Design and Simulation of an Association Rules Algorithm for Exploiting the Data
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作者 Patrici Calvo Rebeca Egea-Moreno 《Journal of Computer and Communications》 2021年第12期17-37,共21页
Data mining techniques offer great opportunities for developing ethics lines whose main aim is to ensure improvements and compliance with the values, conduct and commitments making up the code of ethics. The aim of th... Data mining techniques offer great opportunities for developing ethics lines whose main aim is to ensure improvements and compliance with the values, conduct and commitments making up the code of ethics. The aim of this study is to suggest a process for exploiting the data generated by the data generated and collected from an ethics line by extracting rules of association and applying the Apriori algorithm. This makes it possible to identify anomalies and behaviour patterns requiring action to review, correct, promote or expand them, as appropriate. 展开更多
关键词 Data Mining Ethics lines Association Rules Apriori algorithm COMPANY
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Transmission Lines Distance Protection Using Differential Equation Algorithm and Hilbert-Huang Transform
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作者 Xingmao Liu Zhengyou He 《Journal of Power and Energy Engineering》 2014年第4期616-623,共8页
This paper proposed the scheme of transmission lines distance protection based on differential equation algorithms (DEA) and Hilbert-Huang transform (HHT). The measured impedance based on EDA is affected by various fa... This paper proposed the scheme of transmission lines distance protection based on differential equation algorithms (DEA) and Hilbert-Huang transform (HHT). The measured impedance based on EDA is affected by various factors, such as the distributed capacitance, the transient response characteristics of current transformer and voltage transformer, etc. In order to overcome this problem, the proposed scheme applies HHT to improve the apparent impedance estimated by DEA. Empirical mode decomposition (EMD) is used to decompose the data set from DEA into the intrinsic mode functions (IMF) and the residue. This residue has monotonic trend and is used to evaluate the impedance of faulty line. Simulation results show that the proposed scheme improves significantly the accuracy of the estimated impedance. 展开更多
关键词 Hilbert-Huang TRANSFORM DIFFERENTIAL EQUATION algorithm DISTANCE PROTECTION Transmission lineS
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A NEW ALGORITHM FOR ADAPTIVE LATTICE FILTERAND ITS APPLICATION IN THE SPEECH LINEARPREDICTIVE SYNTHESIS 被引量:1
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作者 Jiang Taihui (institute of Information Science, Wuji University Jiangmen, Guangdong 529020) 《Journal of Electronics(China)》 1996年第4期325-332,共8页
In this paper, an adaptive line spectral pair filter is derived from an adaptive lattice filter. A least-mean-square(LMS) type adaptive algorithm used to calculate directly the line spectral pair(LSP) coefficients on ... In this paper, an adaptive line spectral pair filter is derived from an adaptive lattice filter. A least-mean-square(LMS) type adaptive algorithm used to calculate directly the line spectral pair(LSP) coefficients on a stage-by-stage basis is presented. Experimental results show that the algorithm has higher convergence rate and lower misadjustment as compared with the other algorithms. The LSP coefficients calculated by the algorithm have been used to carry out speech linear predictive synthesis, resulting in better results than PARCOR coefficients. 展开更多
关键词 line SPECTRAL PAIR FILTER Adaptive LATTICE FILTER linear prediction LMS algorithm
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遗传算法下多线结构光视觉传感器解耦标定方法
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作者 傅龙天 许振宇 +1 位作者 陈钦 Ruel REYES 《传感技术学报》 北大核心 2026年第1期147-152,共6页
针对多线结构光视觉传感器易受环境干扰,导致深度估计不准确、无法获取有效三维信息的问题,研究遗传算法下多线结构光视觉传感器解耦标定方法。该方法通过一阶径向变形模型校正图像点坐标,在此基础上基于移动3次以上的一维靶标,将两个... 针对多线结构光视觉传感器易受环境干扰,导致深度估计不准确、无法获取有效三维信息的问题,研究遗传算法下多线结构光视觉传感器解耦标定方法。该方法通过一阶径向变形模型校正图像点坐标,在此基础上基于移动3次以上的一维靶标,将两个不存在共同视场的线结构光视觉传感器相关联,结合交比定义与不变性相求出整体坐标系中的转换矩阵和交点处的三维坐标。并以最小化移动后标靶特征点重投影坐标与实际坐标之间距离和移动后交点与光平面之间距离为目标构建目标函数,使用多种群遗传算法求解目标函数最优解,实现多线结构光视觉传感器解耦标定。实验结果表明,利用所提方法解耦标定时的皮尔逊相关系数更接近于1,可以较为准确地完成解耦标定。 展开更多
关键词 光视觉传感器 解耦标定 多种群遗传算法 多线结构 一维靶标
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基于几何-语义约束与扩散增强的线描生成
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作者 贵向泉 张继续 +2 位作者 李立 李琪 张斌轩 《计算机技术与发展》 2026年第1期55-63,共9页
彩陶作为中国历史悠久的文物,具有重要的艺术与文化研究价值。针对彩陶线描生成中普遍存在的结构丢失、线条歪曲和细节模糊等问题,提出了一种双阶段高保真重构模型——GS-CycleDiff。以CycleGAN为基础,设计几何损失和语义损失,分别利用M... 彩陶作为中国历史悠久的文物,具有重要的艺术与文化研究价值。针对彩陶线描生成中普遍存在的结构丢失、线条歪曲和细节模糊等问题,提出了一种双阶段高保真重构模型——GS-CycleDiff。以CycleGAN为基础,设计几何损失和语义损失,分别利用MiDaS单目深度估计生成的伪深度图与原始照片深度图对齐,确保线描画在关键几何结构处的连贯性;并借助CLIP模型提取图像语义特征,通过最小化输入照片的CLIP和生成的线描画之间的距离,进行约束生成结果与原图在文化符号层面的对应关系。随后,将初步生成的线描画输入轻量级扩散去噪网络,通过多步迭代去噪和细节增强,抑制背景噪声、强化线条清晰度。实验结果表明,GS-CycleDiff生成的图像在线条清晰度、几何结构、语义一致性及整体视觉真实感方面,均显著优于传统CycleGAN模型及其他对比模型,并能在多种风格和复杂背景下生成精细的线描图像。 展开更多
关键词 线描画 CycleGAN GS-CycleDiff算法 几何损失 语义损失 扩散模型
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面向蓄意物理攻击下电-气综合能源系统韧性提升的协同加固策略
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作者 李少岩 戴瑞恒 +4 位作者 张涛 顾雪平 屠竞哲 冀鲁豫 白岩松 《电力自动化设备》 北大核心 2026年第1期40-48,共9页
在蓄意物理攻击场景下,电-气综合能源系统极易出现大规模停电和严重的燃气供应中断事件,制定事前加固方案可提升系统整体的防御能力。面向蓄意物理攻击场景,以系统失负荷量评估电-气综合能源系统的韧性水平,实现不同能源形式负荷损失的... 在蓄意物理攻击场景下,电-气综合能源系统极易出现大规模停电和严重的燃气供应中断事件,制定事前加固方案可提升系统整体的防御能力。面向蓄意物理攻击场景,以系统失负荷量评估电-气综合能源系统的韧性水平,实现不同能源形式负荷损失的统一表征。充分计及不同能源系统攻击难度与效果的差异性,建立基于主从博弈的3层两阶段事前线路加固方案优化模型,并采用列与约束生成算法对模型进行求解,有效识别最恶劣攻击场景并得到最优加固策略。以修改的新英格兰10机39节点电力系统与比利时20节点天然气系统为算例进行仿真分析,结果验证了在电-气综合能源系统蓄意物理攻击防御研究中计及电-气系统耦合特性的必要性,所得协同加固策略能在不同的攻击资源水平下有效提升系统整体的防御韧性。 展开更多
关键词 电-气综合能源系统 蓄意物理攻击 韧性提升 线路加固 列与约束生成算法
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P|rj,on-line|∑C_j的一类在线算法与竞争比分析 被引量:2
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作者 刘培海 鲁习文 《运筹与管理》 CSCD 2007年第3期56-60,65,共6页
本文研究平等机上的在线排序问题,优化目标是使总完工时间最小,算法SSPT是此问题的一类在线算法,论文引入一个拟时间表,此时间表具有SRPT时间表的部分性质,论文通过此辅助时间表证明了SSPT算法是(3-1/m)-competitive的。
关键词 应用数学 竞争比 在线算法 排序 平行机
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平行机的实时到达on-line算法下界的改进 被引量:1
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作者 陈仕平 姚恩瑜 《高校应用数学学报(A辑)》 CSCD 北大核心 1999年第3期315-318,共4页
本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明... 本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明了该在线问题不存在性能比小于1.3473的on-line算法.本文将此界改进为(5-5)/2. 展开更多
关键词 排序 on-line算法 平行机 组合最优化 实时到达
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非平衡大气辐射强度与透过率的Line-By-Line计算模式 被引量:1
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作者 朱世德 向安平 《计算物理》 CSCD 北大核心 1998年第5期110-118,共9页
导出了非局域热力学平衡(NLTE)大气辐射强度与透过率的基本公式,以及NLT和LTE的线强、光学厚度和透过率的关系。假设转动能级是热力学平衡(LTE)的,建立了一个精确的LinebyLineNLTE辐射强度与透过... 导出了非局域热力学平衡(NLTE)大气辐射强度与透过率的基本公式,以及NLT和LTE的线强、光学厚度和透过率的关系。假设转动能级是热力学平衡(LTE)的,建立了一个精确的LinebyLineNLTE辐射强度与透过率的有效算法来计算较高层行星大气红外活跃样品的辐射强度。计算了地球大气16O396μm带在白天、夜晚和NLTE、LTE条件下的临边光谱辐射强度、线积分辐射强度、带积分辐射强度和合成光谱辐射强度,揭示了NLTE辐射强度对LTE辐射强度有显著而重要的偏离。 展开更多
关键词 非局域热力学平衡(NLTE) 发射与透射 辐射强度与透过率 line-by-line算法
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