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Application of single neuron adaptive PID controller during the process of timber drying 被引量:4
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作者 张冬妍 刘亚秋 曹军 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期244-248,共5页
The paper presents a method of using single neuron adaptive PID control for adjusting system or servo system to implement timber drying process control, which combines the thought of parameter adaptive PID control and... The paper presents a method of using single neuron adaptive PID control for adjusting system or servo system to implement timber drying process control, which combines the thought of parameter adaptive PID control and the character of neural network on exactly describing nonlinear and uncertainty dynamic process organically. The method implements functions of adaptive and self-learning by adjusting weighting parameters. Adaptive neural network can make some output trail given hoping value to decouple in static state. The simulation result indicates the validity, veracity and robustness of the method used in the timber drying process 展开更多
关键词 process control Timber drying single neuron Adaptive control PID control
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A Note of the Uniqueness Criterion for Single Birth Processes
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作者 吴群英 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期88-92,共5页
This paper is devoted to studying the si ngle birth processes. The uniqueness criterion for the processes is presented.
关键词 single birth process uniqueness criterion zero _exit REGULAR
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Three-dimensional simulation of fabrication process-dependent effects on single event effects of SiGe heterojunction bipolar transistor 被引量:2
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作者 张晋新 贺朝会 +3 位作者 郭红霞 李培 郭宝龙 吴宪祥 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第8期542-550,共9页
The fabrication process dependent effects on single event effects (SEEs) are investigated in a commercial silicon- germanium heterojunction bipolar transistor (SiGe HBT) using three-dimensional (3D) TCAD simulat... The fabrication process dependent effects on single event effects (SEEs) are investigated in a commercial silicon- germanium heterojunction bipolar transistor (SiGe HBT) using three-dimensional (3D) TCAD simulations. The influences of device structure and doping concentration on SEEs are discussed via analysis of current transient and charge collection induced by ions strike. The results show that the SEEs representation of current transient is different from representation of the charge collection for the same process parameters. To be specific, the area of C/S junction is the key parameter that affects charge collection of SEE. Both current transient and charge collection are dependent on the doping of collector and substrate. The base doping slightly influences transient currents of base, emitter, and collector terminals. However, the SEEs of SiGe HBT are hardly affected by the doping of epitaxial base and the content of Ge. 展开更多
关键词 SiGe HBT single event effects fabrication process dependence 3D simulation
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Relationship of public preferences and behavior in residential outdoor spaces using analytic hierarchy process and principal component analysis—a case study of Hangzhou City, China 被引量:7
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作者 SHI Jian-ren ZHAO Xiu-min +2 位作者 GE Jian HOKAO Kazunori WANG Zhu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第8期1372-1385,共14页
This study examined public attitudes concerning the value of outdoor spaces which people use daily. Two successive analyses were performed based on data from common residents and college students in the city of Hangzh... This study examined public attitudes concerning the value of outdoor spaces which people use daily. Two successive analyses were performed based on data from common residents and college students in the city of Hangzhou, China. First, citizens registered various items constituting desirable values of residential outdoor spaces through a preliminary questionnaire. The result proposed three general attributes (functional, aesthetic and ecological) and ten specific qualities of residential outdoor spaces. An analytic hierarchy process (AHP) was applied to an interview survey in order to clarify the weights among these attributes and qualities. Second, principal factors were extracted from the ten specific qualities with principal component analysis (PCA) for both the common case and the campus case. In addition, the variations of respondents’ groups were classified with cluster analysis (CA) using the results of the PCA. The results of the AHP application found that the public prefers the functional attribute, rather than the aesthetic attribute. The latter is always viewed as the core value of open spaces in the eyes of architects and designers. Fur-thermore, comparisons of ten specific qualities showed that the public prefers the open spaces that can be utilized conveniently and easily for group activities, because such spaces keep an active lifestyle of neighborhood communication, which is also seen to protect human-regarding residential environments. Moreover, different groups of respondents diverge largely in terms of gender, age, behavior and preference. 展开更多
关键词 Public preference Open space Analytic hierarchy process (AHP) Principal component analysis (PCA) Cluster analysis (CA)
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Relationships between the surface quality of a single crystal copper ingot and the process parameters of a heated mould continuous casting method 被引量:1
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作者 G.J.Xu Z.F.Ding +3 位作者 Y.T.Ding S.H.Kou G.L.Liu C.L.Feng 《China Foundry》 SCIE CAS 2004年第S1期62-66,共5页
The relationships between the surface quality of a single crystal copper ingot and the process parameters of heated mould continuous casting method were studied experimentally using our own design of horizontal heated... The relationships between the surface quality of a single crystal copper ingot and the process parameters of heated mould continuous casting method were studied experimentally using our own design of horizontal heated mould continuous casting apparatus, and the mechanism by which process parameters affect the surface quality of a single crystal copper ingot is analyzed in the present paper. The results show that the process parameters affect the surface quality of a pure copper ingot by affecting the position of the liquid-solid interface in the mould. The position of the liquid-solid interface in the mould must be controlled carefully within an appropriate range, which is determined through a series of experiments, in order to gain a single crystal copper ingot with good surface quality. 展开更多
关键词 heated mould continuous casting single crystal copper surface quality process parameter
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THE DGW-I FURNACE A MATERIALS PROCESSING FACILITY IN "SZ-2" SPACECRAFT 被引量:1
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作者 WANG Jinchang LIU Yan +4 位作者 AI Fei YU Qiang REN Juanxi TAN Xiaochen CEI Weixing 《空间科学学报》 CAS CSCD 北大核心 2002年第z1期154-158,共5页
The DGW-I is a new material processing facility developed in China,which was firstly carried into orbit in November 1999 by the SZ-1 spacecraft and then in January 2001 carried by SZ-2 into space again,and successfull... The DGW-I is a new material processing facility developed in China,which was firstly carried into orbit in November 1999 by the SZ-1 spacecraft and then in January 2001 carried by SZ-2 into space again,and successfully processed 6 samples of materials,including 3 samples of alloys,2 of semiconductors and 1 sample of oxide crystal. 展开更多
关键词 MICROGRAVITY space material science Material processing facility
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REALIZATION OF QUICK-LOOK IMAGING FOR SPACEBORNE SAR BASED ON PARALLEL PROCESSING 被引量:1
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作者 TangZhi ZhouYinqing LiJingwen 《Journal of Electronics(China)》 2004年第2期152-158,共7页
Large range cell migration is a severe challenge to imaging algorithm for spaceborne SAR. Based on design of Finite Impulse Response (FIR) filter and Range Doppler (RD) algorithm, a realization of quick-look imaging f... Large range cell migration is a severe challenge to imaging algorithm for spaceborne SAR. Based on design of Finite Impulse Response (FIR) filter and Range Doppler (RD) algorithm, a realization of quick-look imaging for large range cell migration is proposed. It realized quick-look imaging of 8 times reduced resolution with parallel processing on memory shared 8 CPU SGI server. According to simulation experiment, this quick-look imaging algorithm with parallel processing can image 16384x16384 SAR raw data within 6 seconds. It reaches the requirement of real-time imaging. 展开更多
关键词 space borne SAR Quick-look imaging Range cell migration Parallel processing
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Word Embeddings and Semantic Spaces in Natural Language Processing 被引量:1
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作者 Peter J. Worth 《International Journal of Intelligence Science》 2023年第1期1-21,共21页
One of the critical hurdles, and breakthroughs, in the field of Natural Language Processing (NLP) in the last two decades has been the development of techniques for text representation that solves the so-called curse ... One of the critical hurdles, and breakthroughs, in the field of Natural Language Processing (NLP) in the last two decades has been the development of techniques for text representation that solves the so-called curse of dimensionality, a problem which plagues NLP in general given that the feature set for learning starts as a function of the size of the language in question, upwards of hundreds of thousands of terms typically. As such, much of the research and development in NLP in the last two decades has been in finding and optimizing solutions to this problem, to feature selection in NLP effectively. This paper looks at the development of these various techniques, leveraging a variety of statistical methods which rest on linguistic theories that were advanced in the middle of the last century, namely the distributional hypothesis which suggests that words that are found in similar contexts generally have similar meanings. In this survey paper we look at the development of some of the most popular of these techniques from a mathematical as well as data structure perspective, from Latent Semantic Analysis to Vector Space Models to their more modern variants which are typically referred to as word embeddings. In this review of algoriths such as Word2Vec, GloVe, ELMo and BERT, we explore the idea of semantic spaces more generally beyond applicability to NLP. 展开更多
关键词 Natural Language processing Vector space Models Semantic spaces Word Embeddings Representation Learning Text Vectorization Machine Learning Deep Learning
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Range walk and array rotation in space-time adaptive processing:effects and compensations 被引量:2
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作者 Jinping Sun Guohua Wang Shiyi Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期537-543,共7页
This paper proposes a unified clutter model incorporating the effects of range walk and array rotation for space-time adaptive processing(STAP) in airborne multi-channel early-warning radar.Based on this clutter mod... This paper proposes a unified clutter model incorporating the effects of range walk and array rotation for space-time adaptive processing(STAP) in airborne multi-channel early-warning radar.Based on this clutter model,STAP performance is then analyzed from the perspective of covariance matrix tapering(CMT).For STAP performance degradation due to array rotation,a determinate compensation method is proposed based on the CMT method.Numerical examples are provided to verify the analysis and the proposed compensation method. 展开更多
关键词 RADAR space-time adaptive processing CLUTTER covariance matrix tapering.
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Higher-Order Statistics and Nonlinear Processes in Space Plasmas
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作者 Zhao Zhengyu Dai Honggang Shi Xianqing 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第2期181-186,共6页
Statistics of order 2 (variance, auto and cross-correlation functions, auto and cross-power spectra) and 3 (skewness, auto and cross-bicorrelation functions, auto and cross-bispectra) are used to analyze the wave-part... Statistics of order 2 (variance, auto and cross-correlation functions, auto and cross-power spectra) and 3 (skewness, auto and cross-bicorrelation functions, auto and cross-bispectra) are used to analyze the wave-particle interaction in space plasmas. The signals considered here are medium scale electron density irregularities and ELF/ULF electrostatic turbulence. Nonlinearities are mainly observed in the ELF range. They are independently pointed out in time series associated with fluctuations in electronic density and in time series associated with the measurement of one electric field component. Peaks in cross-bicorrelation function and in mutual information clearly show that, in well delimited frequency bands, the wave-particle interactions are nonlinear above a certain level of fluctuations. The way the energy is transferred within the frequencies of density fluctuations is indicated by a bi-spectra analysis. 展开更多
关键词 higher-order statistics nonlinear processes space plasmas
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SPACE-TIME ADAPTIVE PROCESSING FOR AIRBORNE RADAR:A CONVENIENT IMPLEMENTATION APPROACH 被引量:2
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作者 Wang Yongliang Peng Yingning(Dept. of Electronic Engineering, Tsinghua University, Beijing, 100084) 《Journal of Electronics(China)》 1996年第4期310-318,共9页
A convenient implementation approach to space-time adaptive processing for airborne radar has been proposed, which is added by some auxiliary array elements in the area of main-lobe clutter on the basis of 2-D Capon a... A convenient implementation approach to space-time adaptive processing for airborne radar has been proposed, which is added by some auxiliary array elements in the area of main-lobe clutter on the basis of 2-D Capon approach . It is of practical use for its small computational load. This approach possesses the ideal performance in the area of main-lobe clutter . In addition, the approach which is added by some auxiliary beams in the area of main-lobe clutter has also been discussed. 展开更多
关键词 AIRBORNE radar space-TIME adaptive processing(STAP) CLUTTER SUPPRESSION
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Number of Tardy Jobs of Single Machine Scheduling Problem with Variable Processing Time
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作者 朱健梅 《Journal of Modern Transportation》 1999年第1期88-95,共8页
The number of tardy jobs of the single machine scheduling problem with a variable processing time is studied in accordance with the published instances of traffic transportation management engineering. It is proved ... The number of tardy jobs of the single machine scheduling problem with a variable processing time is studied in accordance with the published instances of traffic transportation management engineering. It is proved by 3 partition problem that if the problem is of ready time and common deadline constrained, its complexity is NP hard in the strong sense. Finally, a polynomial algorithm for solving unit processing time and common deadline problems is proposed. 展开更多
关键词 NUMBER of tardy JOBS single machine scheduling problem VARIABLE processing time STRONG NP HARDNESS algorithm.
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Preparation of single-phase ammonium dimolybdate by combination process 被引量:3
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作者 ZHANG Bao XIA Xiaomei LI Qian 《Rare Metals》 SCIE EI CAS CSCD 2012年第5期517-522,共6页
A novel method for the preparation of single-phase ammonium dimolybdate with industrial ammonium molybdate was studied. Various in- fluential factors were evaluated in the paper, including reaction temperature, reacti... A novel method for the preparation of single-phase ammonium dimolybdate with industrial ammonium molybdate was studied. Various in- fluential factors were evaluated in the paper, including reaction temperature, reaction time, initial molybdenum concentration, initial NH_3 /Mo molar ratio, and stirring speed. Under the optimum experimental conditions, the crystallization rate of product is 85.23%. The X-ray diffraction (XRD) analysis and chemical analysis show that the product is single-phase ammonium dimolybdate, and no impurity phases exist. The scanning electronic microscope (SEM) image reveals uniform particle size, good particle dispersion, and no agglomeration between particles. Meanwhile, the final pH value of acidification was investigated. The total molybdenum recovery can reach up to 99.40%, and the main phases of acidification product are the same as those of raw material with the final pH value of 1.5. This determines that the acidification product can be used as a raw material to produce single-phase ammonium dimolybdate. 展开更多
关键词 single-phase ammonium dimolybdate combination process crystallization rate phase composition total molybdenum recovery
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ISHIKAWA ITERATIVE PROCESS IN UNIFORMLY SMOOTH BANACH SPACES
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作者 HUANG Zhen-yu(黄震宇) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第11期1306-1310,共5页
Let E be a uniformly smooth Banach space, K be a nonempty closed convex subset of E, and suppose: T: K --> K is a continuous Phi-strongly pseudocontractive operator with a bounded range. Using a new analytical meth... Let E be a uniformly smooth Banach space, K be a nonempty closed convex subset of E, and suppose: T: K --> K is a continuous Phi-strongly pseudocontractive operator with a bounded range. Using a new analytical method, under general cases, the Ishikawa iterative process {x(n)} converges strongly to the unique fixed point x* of the operator T were proved. The paper generalizes and extends a lot of recent corresponding results. 展开更多
关键词 Ishikawa iterative process Phi-stongly pseudocontractive operators uniformly smooth Banach spaces
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Direct data domain approach to space-time adaptive processing 被引量:2
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作者 Wen Xiaoqin Han Chongzhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期59-64,共6页
In non-homogeneous environment, traditional space-time adaptive processing doesn't effectively suppress interference and detect target, because the secondary data don' t exactly reflect the statistical characteristi... In non-homogeneous environment, traditional space-time adaptive processing doesn't effectively suppress interference and detect target, because the secondary data don' t exactly reflect the statistical characteristic of the range cell under test. A ravel methodology utilizing the direct data domain approach to space-time adaptive processing ( STAP ) in airbome radar non-homogeneous environments is presented. The deterministic least squares adaptive signal processing technique operates on a "snapshot-by-snapshot" basis to dethrone the adaptive adaptive weights for nulling interferences and estimating signal of interest (SOI). Furthermore, this approach eliminates the requirement for estimating the covariance through the data of neighboring range cell, which eliminates calculating the inverse of covariance, and can be implemented to operate in real-time. Simulation results illustrate the efficiency of interference suppression in non-homogeneous environment. 展开更多
关键词 space-time adaptive processing direct data domain interference suppression.
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A Class of Single Machine Scheduling Problems with Variable Processing Time
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作者 周荷芳 周贤伟 《Journal of Modern Transportation》 2001年第1期93-100,共8页
In this paper, single machine scheduling problems with variable processing time are raised. The criterions of the problem considered are minimizing scheduling length of all jobs, flow time and number of tardy jobs and... In this paper, single machine scheduling problems with variable processing time are raised. The criterions of the problem considered are minimizing scheduling length of all jobs, flow time and number of tardy jobs and so on. The complexity of the problem is determined. [WT5HZ] 展开更多
关键词 single machine scheduling problem NP-HARD variable processing time complexity theory
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Strong NP-Hardness of Single Machine Scheduling Problems with Variable Processing Time
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作者 周贤伟 杜文 朱健梅 《Journal of Modern Transportation》 1998年第2期78-88,共11页
In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' ... In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' of the job on position i and a “normal' processing time of the job. The criteria considered is to minimize scheduled length of all jobs. A lemma is proposed and proved. In no deadline constrained condition, the problem belongs to polynomial time algorithm. It is proved by using 3 partition that if the problem is deadline constrained, its complexity is strong NP hard. Finally, a conjuncture is proposed that is to be proved. 展开更多
关键词 single machine scheduling problem variable processing time strong NP hardness.
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Nonlinear dynamics and coupling effect of libration and vibration of tethered space robot in deorbiting process
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作者 王班 郭吉丰 +1 位作者 冯吉根 王剑 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第5期1095-1105,共11页
In order to control the growth of space debris,a novel tethered space robot(TSR) was put forward.After capture,the platform,tether,and target constituted a tethered combination system.General nonlinear dynamics of the... In order to control the growth of space debris,a novel tethered space robot(TSR) was put forward.After capture,the platform,tether,and target constituted a tethered combination system.General nonlinear dynamics of the tethered combination system in the post-capture phase was established with the consideration of the attitudes of two spacecrafts and the quadratic nonlinear elasticity of the tether.The motion law of the tethered combination in the deorbiting process with different disturbances was simulated and discussed on the premise that the platform was only controlled by a constant thrust force.It is known that the four motion freedoms of the tethered combination are coupled with each other in the deorbiting process from the simulation results.A noticeable phenomenon is that the tether longitudinal vibration does not decay to vanish even under the large tether damping with initial attitude disturbances due to the coupling effect.The approximate analytical solutions of the dynamics for a simplified model are obtained through the perturbation method.The condition of the inter resonance phenomenon is the frequency ratio λ_1=2.The case study shows good accordance between the analytical solutions and numerical results,indicating the effectiveness and correctness of approximate analytical solutions. 展开更多
关键词 tethered space robot general nonlinear dynamics deorbiting process perturbation method inter resonance phenomenon
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Design of 512-bit logic process-based single poly EEPROM IP
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作者 金丽妍 JANG Ji-Hye +2 位作者 余忆宁 HA Pan-Bong KIM Young-Hee 《Journal of Central South University》 SCIE EI CAS 2011年第6期2036-2044,共9页
A single poly EEPROM cell circuit sharing the deep N-well of a cell array was designed using the logic process. The proposed cell is written by the FN tunneling scheme and the cell size is 41.26 μm2, about 37% smalle... A single poly EEPROM cell circuit sharing the deep N-well of a cell array was designed using the logic process. The proposed cell is written by the FN tunneling scheme and the cell size is 41.26 μm2, about 37% smaller than the conventional cell. Also, a small-area and low-power 512-bit EEPROM IP was designed using the proposed cells which was used for a 900 MHz passive UHF RFID tag chip. To secure the operation of the cell proposed with 3.3 V devices and the reliability of the used devices, an EEPROM core circuit and a DC-DC converter were proposed. Simulation results for the designed EEPROM IP based on the 0.18μm logic process show that the power consumptions in read mode, program mode and erase mode are 11.82, 25.15, and 24.08 ~tW, respectively, and the EEPROM size is 0.12 mm2. 展开更多
关键词 single poly EEPROM cell Fowler-Nordheim tunneling logic process radio frequency identification small area
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A Genetic Algorithm for Single Machine Scheduling with Fuzzy Processing Time and Multiple Objectives
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作者 吴超超 顾幸生 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期185-189,共5页
In this paper, by considering the fuzzy nature of the data in real-life problems, single machine scheduling problems with fuzzy processing time and multiple objectives are formulated and an efficient genetic algorithm... In this paper, by considering the fuzzy nature of the data in real-life problems, single machine scheduling problems with fuzzy processing time and multiple objectives are formulated and an efficient genetic algorithm which is suitable for solving these problems is proposed. As illustrative numerical examples, twenty jobs processing on a machine is considered. The feasibility and effectiveness of the proposed method have been demonstrated in the simulation. 展开更多
关键词 SCHEDULING single machine genetic algorithms fuzzy processing time multiple objectives
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