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Integrated parallel forecasting model based on modified fuzzy time series and SVM 被引量:1
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作者 Yong Shuai Tailiang Song Jianping Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第4期766-775,共10页
A dynamic parallel forecasting model is proposed, which is based on the problem of current forecasting models and their combined model. According to the process of the model, the fuzzy C-means clustering algorithm is ... A dynamic parallel forecasting model is proposed, which is based on the problem of current forecasting models and their combined model. According to the process of the model, the fuzzy C-means clustering algorithm is improved in outliers operation and distance in the clusters and among the clusters. Firstly, the input data sets are optimized and their coherence is ensured, the region scale algorithm is modified and non-isometric multi scale region fuzzy time series model is built. At the same time, the particle swarm optimization algorithm about the particle speed, location and inertia weight value is improved, this method is used to optimize the parameters of support vector machine, construct the combined forecast model, build the dynamic parallel forecast model, and calculate the dynamic weight values and regard the product of the weight value and forecast value to be the final forecast values. At last, the example shows the improved forecast model is effective and accurate. 展开更多
关键词 fuzzy C-means clustering fuzzy time series interval partitioning support vector machine particle swarm optimization algorithm parallel forecasting
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Multi-factor high-order intuitionistic fuzzy timeseries forecasting model 被引量:1
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作者 Ya'nan Wang Yingjie Lei +1 位作者 Yang Lei Xiaoshi Fan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1054-1062,共9页
Fuzzy sets theory cannot describe the neutrality degreeof data, which has largely limited the objectivity of fuzzy time seriesin uncertain data forecasting. With this regard, a multi-factor highorderintuitionistic fuz... Fuzzy sets theory cannot describe the neutrality degreeof data, which has largely limited the objectivity of fuzzy time seriesin uncertain data forecasting. With this regard, a multi-factor highorderintuitionistic fuzzy time series forecasting model is built. Inthe new model, a fuzzy clustering algorithm is used to get unequalintervals, and a more objective technique for ascertaining membershipand non-membership functions of the intuitionistic fuzzy setis proposed. On these bases, forecast rules based on multidimensionalintuitionistic fuzzy modus ponens inference are established.Finally, contrast experiments on the daily mean temperature ofBeijing are carried out, which show that the novel model has aclear advantage of improving the forecast accuracy. 展开更多
关键词 multi-factor high-order intuitionistic fuzzy time series forecasting model intuitionistic fuzzy inference.
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Research on Short-Term Load Forecasting of Distribution Stations Based on the Clustering Improvement Fuzzy Time Series Algorithm
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作者 Jipeng Gu Weijie Zhang +5 位作者 Youbing Zhang Binjie Wang Wei Lou Mingkang Ye Linhai Wang Tao Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2221-2236,共16页
An improved fuzzy time series algorithmbased on clustering is designed in this paper.The algorithm is successfully applied to short-term load forecasting in the distribution stations.Firstly,the K-means clustering met... An improved fuzzy time series algorithmbased on clustering is designed in this paper.The algorithm is successfully applied to short-term load forecasting in the distribution stations.Firstly,the K-means clustering method is used to cluster the data,and the midpoint of two adjacent clustering centers is taken as the dividing point of domain division.On this basis,the data is fuzzed to form a fuzzy time series.Secondly,a high-order fuzzy relation with multiple antecedents is established according to the main measurement indexes of power load,which is used to predict the short-term trend change of load in the distribution stations.Matlab/Simulink simulation results show that the load forecasting errors of the typical fuzzy time series on the time scale of one day and one week are[−50,20]and[−50,30],while the load forecasting errors of the improved fuzzy time series on the time scale of one day and one week are[−20,15]and[−20,25].It shows that the fuzzy time series algorithm improved by clustering improves the prediction accuracy and can effectively predict the short-term load trend of distribution stations. 展开更多
关键词 Short-term load forecasting fuzzy time series K-means clustering distribution stations
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Modeling the Nigerian Bonny Light Crude Oil Price: The Power of Fuzzy Time Series
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作者 Desmond Chekwube Bartholomew Ukamaka Cynthia Orumie +2 位作者 Chukwudi Paul Obite Blessing Iheoma Duru Felix Chikereuba Akanno 《Open Journal of Modelling and Simulation》 2021年第4期370-3900,共21页
<span style="font-family:Verdana;">Several authors have used different classical statistical models to fit the Nigerian Bonny Light crude oil price but the application of machine learning models and Fu... <span style="font-family:Verdana;">Several authors have used different classical statistical models to fit the Nigerian Bonny Light crude oil price but the application of machine learning models and Fuzzy Time Series model on the crude oil price has been grossly understudied. Therefore, in this study, a classical statistical model</span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">—</span><span style="font-family:Verdana;">Autoregressive Integrated Moving Average (ARIMA), two machine learning models</span><span style="font-family:Verdana;">—</span><span style="font-family:Verdana;">Artificial Neural Network (ANN) and Random Forest (RF) and Fuzzy Time Series (FTS) Model were compared in modeling the Nigerian Bonny Light crude oil price data for the periods </span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">from</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> January, 2006 to December, 2020. The monthly secondary data were collected from the Nigerian National Petroleum Corporation (NNPC) and Reuters website and divided into train (70%) and test (30%) sets. The train set was used in building the models and the models were validated using the test set. The performance measures used for the comparison include: The modified Diebold-Mariano test, the Root Mean Square Error (RMSE), the Mean Absolute Percentage Error (MAPE) and Nash-Sutcliffe Efficiency (NSE) values. Based on the performance measures, ANN (4, 1, 1) and RF performed better than ARIMA (1, 1, 0) model but FTS model using Chen’s algorithm outperformed every other model. The results recommend the use of FTS model for forecasting future values of the Nigerian Bonny Light Crude oil. However, a hybrid model of ARIMA-ANN or ARIMA-RF should be built and compared with Chen’s algorithm FTS model for the same data set to further verify the power of FTS model using Chen’s algorithm.</span></span></span> 展开更多
关键词 ARIMA Artificial Neural Network Chen’s Algorithm fuzzy time Series Random Forest
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Two-Factor Fuzzy Time Series for Equipment Data Prediction
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作者 HE Shanhong RONG Baizhong +4 位作者 QU Meng WANG Shuangfei LI guanhuan WANG Fengyang WU Jin 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第5期684-690,共7页
The data forecasting of plant equipment plays an important role in assurance of the safe and reliable operation of the plant equipment. Thus, it is necessary to improve the accuracy of data forecasting of the equipmen... The data forecasting of plant equipment plays an important role in assurance of the safe and reliable operation of the plant equipment. Thus, it is necessary to improve the accuracy of data forecasting of the equipment. A new two-factor fuzzy time series algorithm is proposed to forecast the data of the plant equipment.This method not only overcomes the limitations of one factor fuzzy time series algorithm, but also overcomes the drawbacks of traditional two-factor fuzzy time series algorithm. The collected data is used in the power plant to conduct experiments, where the metrics is Mean Absolute Percentage Error(MAPE). The results show that this method is superior to the existing two-factor fuzzy time series algorithms, and yields good results in the equipment prediction. 展开更多
关键词 equipment prediction fuzzy time series two-factor fuzzy time series
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A fuzzy time series forecasting method induced by intuitionistic fuzzy sets 被引量:1
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作者 Sanjay Kumar Sukhdev Singh Gangwar 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2015年第4期130-152,共23页
Intuitionistic fuzzy sets(IFSs)are well established as a tool to handle the hesitation in the decision system.In this research paper,fuzzy sets induced by IFS are used to develop a fuzzy time series forecasting model ... Intuitionistic fuzzy sets(IFSs)are well established as a tool to handle the hesitation in the decision system.In this research paper,fuzzy sets induced by IFS are used to develop a fuzzy time series forecasting model to incorporate degree of hesitation(nondeterminacy).To improve the forecasting accuracy,induced fuzzy sets are used to establish fuzzy logical relations.To verify the performance of the proposed model,it is implemented on one of the benchmarking time series data.Further,developed forecasting method is also tested and validated by applying it on a financial time series data.In order to show the accuracy in forecasting,the method is compared with other forecasting methods using different error measures. 展开更多
关键词 fuzzy time series intuitionistic fuzzy sets nondeterminacy induced fuzzy set data models.
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A Fuzzy Time Series Model Based on Improved Fuzzy Function and Cluster Analysis Problem
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作者 Tai Vovan Thuy Lethithu 《Communications in Mathematics and Statistics》 SCIE 2022年第1期51-66,共16页
Based on the improvement in establishing the relations of data,this study proposes a new fuzzy time series model.In this model,the suitable number of fuzzy sets and their specific elements are determined automatically... Based on the improvement in establishing the relations of data,this study proposes a new fuzzy time series model.In this model,the suitable number of fuzzy sets and their specific elements are determined automatically.In addition,using the percentage variations of series between consecutive periods of time,we build the fuzzy function.Incorporating all these improvements,we have a new fuzzy time series model that is better than many existing ones through the well-known data sets.The calculation of the proposed model can be performed conveniently and efficiently by a MATLAB procedure.The proposed model is also used in forecasting for an urgent problem in Vietnam.This application also shows the advantages of the proposed model and illustrates its effectiveness in practical application. 展开更多
关键词 Cluster analysis FORECAST fuzzy time series MODEL
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Strongα-cut and associated membership-based modeling for fuzzy time series forecasting
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作者 Gunjan Goyal Dinesh C.S.Bisht 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2021年第1期53-72,共20页
In this paper,a method is proposed to deal with factors affecting the fuzzy time series forecasting.A new fuzzification process is used by considering all the fuzzy sets with nonzero membership values corresponding to... In this paper,a method is proposed to deal with factors affecting the fuzzy time series forecasting.A new fuzzification process is used by considering all the fuzzy sets with nonzero membership values corresponding to the data points.A strong alpha-cut based method is presented to select appropriate fuzzy logical relationships that carry importance in analyzing the trend of time series.Further,a unique defuzzification approach based on weights is proposed to get crisp variation.This obtained variation is finally converted to the forecasted value.The presented method is tested on the benchmark enrolment dataset of Alabama University and seven datasets of the Taiwan Capitalization Weighted Stock Index.On comparing the results,it is observed that the presented method performs better than the existing methods.Also,the statistical measures indicate the good forecasting results of the presented method. 展开更多
关键词 Associated membership grade forecasting fuzzy logical relationship fuzzy time series strongα-cut
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A COMPUTATIONAL METHOD FOR FUZZY TIME SERIES FORECASTING BASED ON DIFFERENCE PARAMETERS
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作者 BHAGAWATI P.JOSHI SANJAY KUMAR 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2013年第1期22-33,共12页
Present study proposes a method for fuzzy time series forecasting based on difference parameters.The developed method has been presented in a form of simple computational algorithm.It utilizes various difference param... Present study proposes a method for fuzzy time series forecasting based on difference parameters.The developed method has been presented in a form of simple computational algorithm.It utilizes various difference parameters being implemented on current state for forecasting the next state values to accommodate the possible vagueness in the data in an efficient way.The developed model has been simulated on the historical student enrollments data of University of Alabama and the obtained forecasted values have been compared with the existing methods to show its superiority.Further,the developed model has also been implemented in forecasting the movement of market prices of share of State Bank of India(SBI)at Bombay Stock Exchange(BSE),India. 展开更多
关键词 fuzzy time series time variant fuzzy membership grade computational algorithm.
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Denoising Nonlinear Time Series Using Singular Spectrum Analysis and Fuzzy Entropy 被引量:1
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作者 江剑 谢洪波 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期19-23,共5页
We present a hybrid singular spectrum analysis (SSA) and fuzzy entropy method to filter noisy nonlinear time series. With this approach, SSA decomposes the noisy time series into its constituent components including... We present a hybrid singular spectrum analysis (SSA) and fuzzy entropy method to filter noisy nonlinear time series. With this approach, SSA decomposes the noisy time series into its constituent components including both the deterministic behavior and noise, while fuzzy entropy automatically differentiates the optimal dominant components from the noise based on the complexity of each component. We demonstrate the effectiveness of the hybrid approach in reconstructing the Lorenz and Mackey--Class attractors, as well as improving the multi-step prediction quality of these two series in noisy environments. 展开更多
关键词 of on or in Denoising Nonlinear time Series Using Singular Spectrum Analysis and fuzzy Entropy NLP IS
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FINE-GRAINED DISTRIBUTED MULTIMEDIA SYNCHRONIZA-TION MODEL——ENHANCED FUZZY-TIMING PETRI NET
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作者 韩莹洁 孙永强 吴哲辉 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第1期62-66,共5页
A fine grained distributed multimedia synchronization model——Enhanced Fuzzy timing Petri Net was proposed which is good at modeling indeterminacy and fuzzy. To satisfy the need of maximum tolerable jitter, the suffi... A fine grained distributed multimedia synchronization model——Enhanced Fuzzy timing Petri Net was proposed which is good at modeling indeterminacy and fuzzy. To satisfy the need of maximum tolerable jitter, the sufficient conditions are given in intra object synchronization. Method to find a proper granularity in inter object synchronization is also given to satisfy skew. Exceptions are detected and corrected as early as possible using restricted blocking method. 展开更多
关键词 multimedia synchronization enhanced fuzzy timing petri net (EFPN) quality of service (QoS)
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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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FUZZY APPROACHING SET AND FUZZYAPPROACHING FUNCTIONAL MAPPING
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作者 曹纯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第11期0-0,0-0+0-0+0-0+0-0+0,共11页
By establishing the concepts of fuzzy approaching set and fuzzy approaching functional mapping and making research on them, a new method for time series prediction is introduced.
关键词 fuzzy approaching set fuzzy approaching functional mapping time series prediction
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Handling higher order time series forecasting approach in intuitionistic fuzzy environment 被引量:1
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作者 Abhishekh Sanjay Kumar 《Journal of Control and Decision》 EI 2020年第4期327-344,共18页
This study presents a new method of forecasting based on a higher order intuitionistic fuzzy time series(FTS)by transforming FTS data into intuitionistic FTS data via defining their appropriate membership and non-memb... This study presents a new method of forecasting based on a higher order intuitionistic fuzzy time series(FTS)by transforming FTS data into intuitionistic FTS data via defining their appropriate membership and non-membership grades.The fuzzification of time series data is intuitionistic fuzzification which is based on the maximum score degree of intuitionistic fuzzy numbers.Also,the intuitionistic fuzzy logical relationship groups are defined and introduced into a defuzzification process for a higher order intuitionistic FTS that enhances in the forecasted output.In order to assess the performance of the proposed method,the method has been implemented on the historical data of rice production.The comparison result shows that the proposed method can achieve a better forecasting accuracy rate in terms of RMSE and MAPE than the existing methods such as Song and Chissom[(1993).Forecasting enrolments with fuzzy time series-Part I.Fuzzy Sets and System,54,1-9],Chen[(1996).Forecasting enrolments based on fuzzy time series.Fuzzy Sets and System,81,311-319],Singh[(2007a).A simple method of forecasting based on fuzzy time series.Applied Mathematics and Computation,186,330-339]and Abhishekh,Gautam,and Singh[(2017).A refined weighted method for forecasting based on type 2 fuzzy time series.International Journal of ModellingandSimulation,38,180-188;(2018).A score function based method of forecasting using intuitionistic fuzzy time series.New Mathematics and Natural Computation,14(1),91-111]. 展开更多
关键词 fuzzy time series intuitionistic fuzzy number membership grades accuracy function higher order IFLR
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Fuzz-TIME: an intelligent system for managing fuzzy temporal information
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作者 Aymen Gammoudi Allel Hadjali Boutheina Ben Yaghlane 《International Journal of Intelligent Computing and Cybernetics》 EI 2017年第2期200-222,共23页
Purpose-Time modeling is a crucial feature in many application domains.However,temporal information often is not crisp,but is subjective and fuzzy.The purpose of this paper is to address the issue related to the model... Purpose-Time modeling is a crucial feature in many application domains.However,temporal information often is not crisp,but is subjective and fuzzy.The purpose of this paper is to address the issue related to the modeling and handling of imperfection inherent to both temporal relations and intervals.Design/methodology/approach-On the one hand,fuzzy extensions of Allen temporal relations are investigated and,on the other hand,extended temporal relations to define the positions of two fuzzy time intervals are introduced.Then,a database system,called Fuzzy Temporal Information Management and Exploitation(Fuzz-TIME),is developed for the purpose of processing fuzzy temporal queries.Findings-To evaluate the proposal,the authors have implemented a Fuzz-TIME system and created a fuzzy historical database for the querying purpose.Some demonstrative scenarios from history domain are proposed and discussed.Research limitations/implications-The authors have conducted some experiments on archaeological data to show the effectiveness of the Fuzz-TIME system.However,thorough experiments on large-scale databases are highly desirable to show the behavior of the tool with respect to the performance and time execution criteria.Practical implications-The tool developed(Fuzz-TIME)can have many practical applications where time information has to be dealt with.In particular,in several real-world applications like history,medicine,criminal and financial domains,where time is often perceived or expressed in an imprecise/fuzzy manner.Social implications-The social implications of this work can be expected,more particularly,in two domains:in the museum to manage,exploit and analysis the piece of information related to archives and historic data;and in the hospitals/medical organizations to deal with time information inherent to data about patients and diseases.Originality/value-This paper presents the design and characterization of a novel and intelligent database system to process and manage the imperfection inherent to both temporal relations and intervals. 展开更多
关键词 Information retrieval fuzzy set theory fuzzy temporal relations fuzzy time intervals Temporal databases
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论《世界末日之战》的时间艺术
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作者 张金玲 《毕节学院学报(综合版)》 2010年第10期92-96,共5页
《世界末日之战》是秘鲁作家略萨的一部以巴西历史为题材的小说。小说试图通过对历史的回顾来表现对拉美历史的独特思考。小说中的时间艺术具有独特性,它一方面以明确的具体时间和自然时序来显示历史事件的客观性,另一方面又以模糊的、... 《世界末日之战》是秘鲁作家略萨的一部以巴西历史为题材的小说。小说试图通过对历史的回顾来表现对拉美历史的独特思考。小说中的时间艺术具有独特性,它一方面以明确的具体时间和自然时序来显示历史事件的客观性,另一方面又以模糊的、不确定的时间概念来展示小说特有的主观性,同时在结构安排上又通过时间的跳跃性、多层面性来呈现时间的立体性特色。 展开更多
关键词 《世界末日之战》 时间艺术 明确性 模糊性 跳跃与多层面性
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Q-Learning-Based Teaching-Learning Optimization for Distributed Two-Stage Hybrid Flow Shop Scheduling with Fuzzy Processing Time 被引量:7
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作者 Bingjie Xi Deming Lei 《Complex System Modeling and Simulation》 2022年第2期113-129,共17页
Two-stage hybrid flow shop scheduling has been extensively considered in single-factory settings.However,the distributed two-stage hybrid flow shop scheduling problem(DTHFSP)with fuzzy processing time is seldom invest... Two-stage hybrid flow shop scheduling has been extensively considered in single-factory settings.However,the distributed two-stage hybrid flow shop scheduling problem(DTHFSP)with fuzzy processing time is seldom investigated in multiple factories.Furthermore,the integration of reinforcement learning and metaheuristic is seldom applied to solve DTHFSP.In the current study,DTHFSP with fuzzy processing time was investigated,and a novel Q-learning-based teaching-learning based optimization(QTLBO)was constructed to minimize makespan.Several teachers were recruited for this study.The teacher phase,learner phase,teacher’s self-learning phase,and learner’s self-learning phase were designed.The Q-learning algorithm was implemented by 9 states,4 actions defined as combinations of the above phases,a reward,and an adaptive action selection,which were applied to dynamically adjust the algorithm structure.A number of experiments were conducted.The computational results demonstrate that the new strategies of QTLBO are effective;furthermore,it presents promising results on the considered DTHFSP. 展开更多
关键词 teaching-learning based optimization Q-learning algorithm two-stage hybrid flow shop scheduling fuzzy processing time
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Mathematical Modeling and a Multiswarm Collaborative Optimization Algorithm for Fuzzy Integrated Process Planning and Scheduling Problem 被引量:1
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作者 Qihao Liu Cuiyu Wang +1 位作者 Xinyu Li Liang Gao 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2024年第2期285-304,共20页
Considering both process planning and shop scheduling in manufacturing can fully utilize their complementarities,resulting in improved rationality of process routes and high-quality and efficient production. Hence,the... Considering both process planning and shop scheduling in manufacturing can fully utilize their complementarities,resulting in improved rationality of process routes and high-quality and efficient production. Hence,the study of Integrated Process Planning and Scheduling (IPPS) has become a hot topic in the current production field. However,when performing this integrated optimization,the uncertainty of processing time is a realistic key point that cannot be neglected. Thus,this paper investigates a Fuzzy IPPS (FIPPS) problem to minimize the maximum fuzzy completion time. Compared with the conventional IPPS problem,FIPPS considers the fuzzy process time in the uncertain production environment,which is more practical and realistic. However,it is difficult to solve the FIPPS problem due to the complicated fuzzy calculating rules. To solve this problem,this paper formulates a novel fuzzy mathematical model based on the process network graph and proposes a MultiSwarm Collaborative Optimization Algorithm (MSCOA) with an integrated encoding method to improve the optimization. Different swarms evolve in various directions and collaborate in a certain number of iterations. Moreover,the critical path searching method is introduced according to the triangular fuzzy number,allowing for the calculation of rules to enhance the local searching ability of MSCOA. The numerical experiments extended from the well-known Kim benchmark are conducted to test the performance of the proposed MSCOA. Compared with other competitive algorithms,the results obtained by MSCOA show significant advantages,thus proving its effectiveness in solving the FIPPS problem. 展开更多
关键词 Integrated Process Planning and Scheduling(IPPS) fuzzy processing time fuzzy completion time MultiSwarm Collaborative Optimization Algorithm(MSCOA)
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General coarsened measurement references for revelation of a classical world
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作者 谢东 徐春玲 王安民 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第11期133-137,共5页
It has been found that for a fixed degree of fuzziness in the coarsened references of measurements,the quantum-toclassical transition can be observed independent of the macroscopicity of the quantum state.We explore a... It has been found that for a fixed degree of fuzziness in the coarsened references of measurements,the quantum-toclassical transition can be observed independent of the macroscopicity of the quantum state.We explore a general situation that the degree of fuzziness can change with the rotation angle between two states(different rotation angles represent different references).The fuzziness of reference comes from two kinds of fuzziness:the Hamiltonian(rotation frequency)and the timing(rotation time).For the fuzziness of the Hamiltonian alone,the degree of fuzziness for the reference will change with the rotation angle between two states,and the quantum effects can still be observed with any degree of fuzziness of Hamiltonian.For the fuzziness of timing,the degree of the coarsening reference is unchanged with the rotation angle.During the rotation of the measurement axis,the decoherence environment can also help the classical-to-quantum transition due to changing the direction of the measurement axis. 展开更多
关键词 fuzziness rotation Hamiltonian references unitary timing comes unchanged alone operators
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Nonstationary fuzzy forecasting of wind and wave climate in very long-term scales
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作者 Ch.N.Stefanakos E.Vanem 《Journal of Ocean Engineering and Science》 SCIE 2018年第2期144-155,共12页
Global climate change may have serious impact on human activities in coastal and other areas.Climate change may affect the degree of storminess and,hence,change the wind-driven ocean wave climate.This may affect the r... Global climate change may have serious impact on human activities in coastal and other areas.Climate change may affect the degree of storminess and,hence,change the wind-driven ocean wave climate.This may affect the risks associated with maritime activities such as shipping and offshore oil and gas.So,there is a recognized need to understand better how climate change will affect such processes.Typically,such understanding comes from future projections of the wind and wave climate from numerical climate models and from the stochastic modelling of such projections.This work investigates the applicability of a recently proposed nonstationary fuzzy modelling to wind and wave climatic simulations.According to this,fuzzy inference models(FIS)are coupled with nonstationary time series modelling,providing us with less biased climatic estimates.Two long-term datasets for an area in the North Atlantic Ocean are used in the present study,namely NORA10(57 years)and ExWaCli(30 years in the present and 30 years in the future).Two distinct experiments have been performed to simulate future values of the time series in a climatic scale.The assessment of the simulations by means of the actual values kept for comparison purposes gives very good results. 展开更多
关键词 fuzzy time series Wind and wave data Forecasting NONSTATIONARY Ocean wind and wave climate
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