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甘肃礼县淫羊藿生长环境与品质分析
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作者 张航 张雷雷 +5 位作者 刘大虎 窦维 任旭亚 张萍 刘元春 赵玮 《寒旱农业科学》 2024年第10期949-954,共6页
甘肃南部的礼县是淫羊藿的道地产区,野生品产量大,对当地野生淫羊藿资源进行保护及人工驯化就显得十分重要。为了考察甘肃礼县淫羊藿种植条件与品质的情况,对礼县19个不同区域的野生或家种淫羊藿的种植土壤、灌溉水以及淫羊藿品质等关... 甘肃南部的礼县是淫羊藿的道地产区,野生品产量大,对当地野生淫羊藿资源进行保护及人工驯化就显得十分重要。为了考察甘肃礼县淫羊藿种植条件与品质的情况,对礼县19个不同区域的野生或家种淫羊藿的种植土壤、灌溉水以及淫羊藿品质等关键指标进行了检测。结果显示,19个采样区域的土壤质量在重金属污染和农药残留检测均在国家标准规定的限值范围以内,属于较好的生态土壤;水质也完全符合农田灌溉水质标准;淫羊藿品质各相关指标对照《中华人民共和国药典》要求均达标。通过模糊隶函数综合分析认为,19个采样区域中以太塘镇安家山野生淫羊藿品质最优,其次是中坝镇梁坪村野生淫羊藿,排在第3位的是城关镇东台村家种淫羊藿。 展开更多
关键词 礼县 淫羊藿 生长环境 品质 模糊隶函数 甘肃省
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MINER RULE CONSIDERING FUZZINESS OF STRESS DAMAGE UNDER DIFFERENT LOAD SEQUENCES 被引量:7
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作者 王旭亮 聂宏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期182-186,共5页
Since the traditional Miner rule ignores the influence of the load sequence on the fatigue life, the fuzzy rules are used to analyze the fuzziness of the fatigue damage caused by the stress nearby the fatigue limit un... Since the traditional Miner rule ignores the influence of the load sequence on the fatigue life, the fuzzy rules are used to analyze the fuzziness of the fatigue damage caused by the stress nearby the fatigue limit under different load sequences. The improved fuzzy Miner rule can reflect the influence of the load sequence on the fatigue life. Results of the example show that the prediction error can be reduced from 61.6% to 21.7%. 展开更多
关键词 atigue damage fuzzy rules membership functions load sequence Miner rule
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Fuzzy Comprehensive Evaluation of Urban Traffic Environment Quality
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作者 韩正忠 杨涛 方宁生 《Journal of Southeast University(English Edition)》 EI CAS 2001年第2期72-74,共3页
In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs... In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs and conduct example analysis. The evaluation result is consistent with the real case. So that the method of the fuzzy evaluation is a good one for the environment quality assessment. 展开更多
关键词 fuzzy evaluation membership function traffic environment quality
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INDUCTION MOTOR SPEED CONTROL SYSTEM BASED ON FUZZY NEURAL NETWORK 被引量:1
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作者 徐小增 李叶松 秦忆 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期195-199,共5页
A fuzzy neural network controller with the teaching controller guidance and parameter regulations for vector-controlled induction motor is proposed. The design procedures of the fuzzy neural controller and the teachin... A fuzzy neural network controller with the teaching controller guidance and parameter regulations for vector-controlled induction motor is proposed. The design procedures of the fuzzy neural controller and the teaching controller are described. The parameters of the membership function are regulated by an on-line learning algorithm. The speed responses of the system under the condition, where the target functions are chosen as I qs and ω, are analyzed. The system responses with the variant of parameter moment of inertial J, viscous coefficients B and torque constant K tare also analyzed. Simulation results show that the control scheme and the controller have the advantages of rapid speed response and good robustness. 展开更多
关键词 induction motor fuzzy neural network vector control speed control system
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Similarity measure design and similarity computation for discrete fuzzy data 被引量:7
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作者 LEE Sang-Hyuk PARK Wook-Je JUNG Dong-yean 《Journal of Central South University》 SCIE EI CAS 2011年第5期1602-1608,共7页
The similarity computations for fuzzy membership function pairs were carried out.Fuzzy number related knowledge was introduced,and conventional similarity was compared with distance based similarity measure.The useful... The similarity computations for fuzzy membership function pairs were carried out.Fuzzy number related knowledge was introduced,and conventional similarity was compared with distance based similarity measure.The usefulness of the proposed similarity measure was verified.The results show that the proposed similarity measure could be applied to ordinary fuzzy membership functions,though it was not easy to design.Through conventional results on the calculation of similarity for fuzzy membership pair,fuzzy membership-crisp pair and crisp-crisp pair were carried out.The proposed distance based similarity measure represented rational performance with the heuristic point of view.Furthermore,troublesome in fuzzy number based similarity measure for abnormal universe of discourse case was discussed.Finally,the similarity measure computation for various membership function pairs was discussed with other conventional results. 展开更多
关键词 similarity measure fuzzy number DISTANCE similarity evaluation fuzzy membership function
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Fuzzy entropy design for non convex fuzzy set and application to mutual information 被引量:7
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作者 LEE Sang-Hyuk LEE Sang-Min +1 位作者 SOHN Gyo-Yong KIM Jaeh-Yung 《Journal of Central South University》 SCIE EI CAS 2011年第1期184-189,共6页
Fuzzy entropy was designed for non convex fuzzy membership function using well known Hamming distance measure.The proposed fuzzy entropy had the same structure as that of convex fuzzy membership case.Design procedure ... Fuzzy entropy was designed for non convex fuzzy membership function using well known Hamming distance measure.The proposed fuzzy entropy had the same structure as that of convex fuzzy membership case.Design procedure of fuzzy entropy was proposed by considering fuzzy membership through distance measure,and the obtained results contained more flexibility than the general fuzzy membership function.Furthermore,characteristic analyses for non convex function were also illustrated.Analyses on the mutual information were carried out through the proposed fuzzy entropy and similarity measure,which was also dual structure of fuzzy entropy.By the illustrative example,mutual information was discussed. 展开更多
关键词 fuzzy entropy non convex fuzzy membership function distance measure similarity measure mutual information
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Stabilization design for continuous-time Takagi-Sugeno fuzzy systems based on new relaxed conditions
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作者 潘俊涛 费树岷 +1 位作者 穆朝絮 薛明香 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期550-553,共4页
This paper deals with the problem of stabilization design for a class of continuous-time Takagi-Sugeno(T-S)fuzzy systems.New stabilization conditions are derived based on a relaxed approach in which both fuzzy Lyapu... This paper deals with the problem of stabilization design for a class of continuous-time Takagi-Sugeno(T-S)fuzzy systems.New stabilization conditions are derived based on a relaxed approach in which both fuzzy Lyapunov functions and staircase membership functions are used.Through the staircase membership functions approximating the continuous membership functions of the given fuzzy model,the information of the membership functions can be brought into the stabilization design of the fuzzy systems,thereby significantly reducing the conservativeness in the existing stabilization conditions of the T-S fuzzy systems.Unlike some previous fuzzy Lyapunov function approaches reported in the literature,the proposed stabilization conditions do not depend on the time-derivative of the membership functions that may be the main source of conservatism when considering fuzzy Lyapunov functions analysis.Moreover,conditions for the solvability of the controller design are written in the form of linear matrix inequalities,but not bilinear matrix inequalities,which are easier to be solved by convex optimization techniques.A simulation example is given to demonstrate the validity of the proposed approach. 展开更多
关键词 Takagi-Sugeno fuzzy model fuzzy Lyapunov function staircase membership function linear matrix inequality
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Similarity measure on intuitionistic fuzzy sets 被引量:5
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作者 PARK Jean-Ho HWANG Jai-Hyuk +2 位作者 PARK Wook-Je 魏荷 LEE Sang-Hyuk 《Journal of Central South University》 SCIE EI CAS 2013年第8期2233-2238,共6页
Study of fuzzy entropy and similarity measure on intuitionistic fuzzy sets (IFSs) was proposed and analyzed. Unlike fuzzy set, IFSs contain uncertainty named hesitance, which is contained in fuzzy membership function ... Study of fuzzy entropy and similarity measure on intuitionistic fuzzy sets (IFSs) was proposed and analyzed. Unlike fuzzy set, IFSs contain uncertainty named hesitance, which is contained in fuzzy membership function itself. Hence, designing fuzzy entropy is not easy because of many entropy definitions. By considering different fuzzy entropy definitions, fuzzy entropy on IFSs is designed and discussed. Similarity measure was also presented and its usefulness was verified to evaluate degree of similarity. 展开更多
关键词 similarity measure MULTI-DIMENSION discrete data relative degree power interconnected system
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Similarity measure application to fault detection of flight system 被引量:5
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作者 KIM J +4 位作者 H LEE S H 王洪梅 《Journal of Central South University》 SCIE EI CAS 2009年第5期789-793,共5页
Fault detection technique is introduced with similarity measure. The characteristics of conventional similarity measure based on fuzzy number are discussed. With the help of distance measure, similarity measure is con... Fault detection technique is introduced with similarity measure. The characteristics of conventional similarity measure based on fuzzy number are discussed. With the help of distance measure, similarity measure is constructed explicitly. The designed distance-based similarity measure is applicable to general fuzzy membership functions including non-convex fuzzy membership function, whereas fuzzy number-based similarity measure has limitation to calculate the similarity of general fuzzy membership functions. The applicability of the proposed similarity measure to general fuzzy membership structures is proven by identifying the definition. To decide fault detection of flight system, the experimental data (pitching moment coefficients and lift coefficients) are transformed into fuzzy membership functions. Distance-based similarity measure is applied to the obtained fuzzy membership functions, and similarity computation and analysis are obtained with the fault and normal operation coefficients. 展开更多
关键词 similarity measure fuzzy number distance non-convex membership function
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Determination of coal mine mechanization using fuzzy logic 被引量:4
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作者 Ataei M Khalokakaei R Hossieni M 《Mining Science and Technology》 EI CAS 2009年第2期149-154,共6页
Two of the most important tasks in coal mines are to improve efficiency and to increase production besides keeping safety constantly in mind.In order to obtain these goals,mine mechanization is required.Mine mechaniza... Two of the most important tasks in coal mines are to improve efficiency and to increase production besides keeping safety constantly in mind.In order to obtain these goals,mine mechanization is required.Mine mechanization needs high levels of investment and should therefore be studied carefully before final decisions about mechanization are made.When analysizing the potential for mechanization the following,rather imprecise,factors should be considered:seam inclination and thickness,geological disturbances,seam floor conditions,roof conditions,water at the working face and the extension of seams.In our study we have used fuzzy logic,membership functions and created fuzzy rule-based methods and to considered the ultimate objective:mechanization of mining.As a case study,the mechanization of the Takht coal seams in Iran was investigated.The results show a high potential for mechanization in most of the Takht coal seams. 展开更多
关键词 fuzzy set MECHANIZATION coal seams PRODUCTIVITY SAFETY
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Designing similarity measurement with distance measure and application on laterally directional mode flight test 被引量:1
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作者 PARK Wook-je LEE Sang-min LEE Sang-hyuk 《Journal of Central South University》 SCIE EI CAS 2012年第4期1032-1039,共8页
Similarity measure construction has been proposed as fault detection of flight test method in order to obtain the primary control surface stuck and the combination stuck of primary control.Similarity measures were obt... Similarity measure construction has been proposed as fault detection of flight test method in order to obtain the primary control surface stuck and the combination stuck of primary control.Similarity measures were obtained through analyzing the certainty and uncertainty of fuzzy membership functions,which were designed based on well-known Hamming distance.It was applied to the fault detection of primary control surface stuck of uninhabited aerial vehicle(UAV).At post-failure control surface,if the UAV is controllable and trimmable using other control surfaces,the UAV is able to fly or return to the safety region through reconfiguration of flight control system.To detect the fault,similarity measure computations were carried out.This result could be applicable with the real-time parameter estimation method.By monitoring the value of coefficients due to the control surface deviation,it becomes aware that the control surface fault occurs or not.The control surface stuck position and value were separated by comparing the trim value with the reference value.This is the advantage of increasing in reliability without adding sensors or with additional low cost. 展开更多
关键词 similarity measure fault detection and isolation real-time parameter estimation control surface stuck
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Fuzzy-GA based algorithm for optimal placement and sizing of distribution static compensator (DSTATCOM) for loss reduction of distribution network considering reconfiguration 被引量:1
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作者 Mohammad Mohammadi Mahyar Abasi A.Mohammadi Rozbahani 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期245-258,共14页
This work presents a fuzzy based methodology for distribution system feeder reconfiguration considering DSTATCOM with an objective of minimizing real power loss and operating cost. Installation costs of DSTATCOM devic... This work presents a fuzzy based methodology for distribution system feeder reconfiguration considering DSTATCOM with an objective of minimizing real power loss and operating cost. Installation costs of DSTATCOM devices and the cost of system operation, namely, energy loss cost due to both reconfiguration and DSTATCOM placement, are combined to form the objective function to be minimized. The distribution system tie switches, DSTATCOM location and size have been optimally determined to obtain an appropriate operational condition. In the proposed approach, the fuzzy membership function of loss sensitivity is used for the selection of weak nodes in the power system for the placement of DSTATCOM and the optimal parameter settings of the DFACTS device along with optimal selection of tie switches in reconfiguration process are governed by genetic algorithm(GA). Simulation results on IEEE 33-bus and IEEE 69-bus test systems concluded that the combinatorial method using DSTATCOM and reconfiguration is preferable to reduce power losses to 34.44% for 33-bus system and to 45.43% for 69-bus system. 展开更多
关键词 distribution FACTS (DFACTS) distribution static compensator (DSTATCOM) network reconfiguration genetic algorithm fuzzy membership function power loss reduction
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Modelling spatial vagueness based on type-2 fuzzy set 被引量:1
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作者 杜国宁 朱仲英 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期250-256,共7页
The modelling and formal characterization of spatial vagueness plays an increasingly important role in the imple- mentation of Geographic Information System (GIS). The concepts involved in spatial objects of GIS have ... The modelling and formal characterization of spatial vagueness plays an increasingly important role in the imple- mentation of Geographic Information System (GIS). The concepts involved in spatial objects of GIS have been investigated and acknowledged as being vague and ambiguous. Models and methods which describe and handle fuzzy or vague (rather than crisp or determinate) spatial objects, will be more necessary in GIS. This paper proposes a new method for modelling spatial vagueness based on type-2 fuzzy set, which is distinguished from the traditional type-1 fuzzy methods and more suitable for describing and implementing the vague concepts and objects in GIS. 展开更多
关键词 Fuzzy theory Type-2 fuzzy set Spatial vagueness Geographic Information System (GIS) Membership function(MF)
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Properties of Fuzzy Entropy Based on the Shape Change of Membership Function
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作者 卿铭 秦应兵 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期268-271,共4页
Modification of a fuzzy partition often leads to the change of fuzziness of a fuzzy system. Researches on the change of fuzzy entropy of a fuzzy set, responding to shape alteration of membership function, therefore... Modification of a fuzzy partition often leads to the change of fuzziness of a fuzzy system. Researches on the change of fuzzy entropy of a fuzzy set, responding to shape alteration of membership function, therefore, play a significant role in analysis of the change of fuzziness of a fuzzy system because a fuzzy partition consists of a set of fuzzy sets which satisfy some special constraints. This paper has shown several results about entropy changes of a fuzzy set. First, the entropies of two same type of fuzzy sets have a constant proportional relationship which depends on the ratio of the sizes of their support intervals. Second, as for Triangular Fuzzy Numbers (TFNs), the entropies of any two TFNs which can not be always the same type, also, have a constant proportional relationship which depends on the ratio of the sizes of their support intervals. Hence, any two TFNs with the same sizes of support intervals have the same entropies. Third, concerning two Triangular Fuzzy Sets (TFSs) with same sizes of support intervals and different heights, the relationship of their entropies lies on their height. Finally, we point it out a mistake that Chen's assertion that the entropy of resultant fuzzy set of elevation operation is directly to that of the original one while elevation factor just acts as a propartional factor. These results should contribute to the analysis and design of a fuzzy system. 展开更多
关键词 fuzzy entropy membership function entropy function triangular fuzzy number support interval
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Linearization of T-S fuzzy systems and robust H_∞ control 被引量:4
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作者 YOON Tae-Sung 王法广 +2 位作者 PARK Seung-Kyu KWAK Gun-Pyong AHN Ho-Kyun 《Journal of Central South University》 SCIE EI CAS 2011年第1期140-145,共6页
Takagi-Sugeno(T-S) fuzzy model is difficult to be linearized because of membership functions included.So,novel T-S fuzzy state transformation and T-S fuzzy feedback are proposed for the linearization of T-S fuzzy syst... Takagi-Sugeno(T-S) fuzzy model is difficult to be linearized because of membership functions included.So,novel T-S fuzzy state transformation and T-S fuzzy feedback are proposed for the linearization of T-S fuzzy system.The novel T-S fuzzy state transformation is the fuzzy combination of local linear transformation which transforms local linear models in the T-S fuzzy model into the local linear controllable canonical models.The fuzzy combination of local linear controllable canonical model gives controllable canonical T-S fuzzy model and then nonlinear feedback is obtained easily.After the linearization of T-S fuzzy model,a robust H∞ controller with the robustness of sliding model control(SMC) is designed.As a result,controlled T-S fuzzy system shows the performance of H∞ control and the robustness of SMC. 展开更多
关键词 T-S fuzzy control LINEARIZATION H∞ control sliding mode control
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Multi-Level Fuzzy Comprehensive Assessment of Tourism Resources in Laiyuan County of Hebei Province
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作者 王利军 《Journal of Landscape Research》 2009年第11期94-98,共5页
The membership of every target and the mathematic model of multi-level fuzzy comprehensive assessment are set up by using fuzzy theories and means in this study.Tourism resources of main scenic spots areas in Laiyuan ... The membership of every target and the mathematic model of multi-level fuzzy comprehensive assessment are set up by using fuzzy theories and means in this study.Tourism resources of main scenic spots areas in Laiyuan County of Hebei Province are evaluated and classified by applying the model.The results of evaluation indicate that 10 of these scenic spots such as Baoziwo and Qingyunfeng are grade A,and 6 of them such as Yunpan Valley and Xianrenqiao are grade B.The peak forest scenic area in the Baishishan Geological Park and Shipuxia Scenic Area are grade A,and Jumayuan Scenic Area is grade B.Furthermore,suggestions are put forward based on the scientific and feasible development of tourism resources. 展开更多
关键词 Quality of tourism resources Membership function Multi-level fuzzy comprehensive assessment
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High-speed corner detection based on fuzzy ID3 decision tree
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作者 段汝娇 赵伟 +1 位作者 黄松岭 郝宽胜 《Journal of Central South University》 SCIE EI CAS 2012年第9期2528-2533,共6页
A high-speed comer detection algorithm based on fuzzy ID3 decision tree was proposed. In the algorithm, the Bresenham circle with 3-pixel radius was used as the test mask, overlapping the candidate comers with the nuc... A high-speed comer detection algorithm based on fuzzy ID3 decision tree was proposed. In the algorithm, the Bresenham circle with 3-pixel radius was used as the test mask, overlapping the candidate comers with the nucleus. Connected pixels on the circle were applied to compare the intensity value with the nucleus, with the membership function used to give the fuzzy result. The pixel with maximum information gain was chosen as the parent node to build a binary decision tree. Thus, the comer detector was derived. The pictures taken in Fengtai Railway Station in Beijing were used to test the method. The experimental results show that when the number of pixels on the test mask is chosen to be 9, best result can be obtained. The comer detector significantly outperforms existing detector in computational efficiency without sacrificing the quality and the method also provides high performance against Poisson noise and Gaussian blur. 展开更多
关键词 comer detector fuzzy ID3 algorithm decision tree computation efficiency REAL-TIME
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Carbon emission impact on the operation of virtual power plant with combined heat and power system 被引量:5
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作者 Yu-hang XIA Jun-yong LIU +1 位作者 Zheng-wen HUANG Xu ZHANG 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2016年第5期479-488,共10页
A virtual power plant (VPP) can realize the aggregation of distributed generation in a certain region, and represent distributed generation to participate in the power market of the main grid. With the expansion of ... A virtual power plant (VPP) can realize the aggregation of distributed generation in a certain region, and represent distributed generation to participate in the power market of the main grid. With the expansion of VPPs and ever-growing heat demand of consumers, managing the effect of fluctuations in the amount of available renewable resources on the operation of VPPs and maintaining an economical supply of electric power and heat energy to users have been important issues. This paper proposes the allocation of an electric boiler to realize wind power directly converted for supplying heat, which can not only overcome the limitation of beat output from a combined heat and power (CHP) unit, but also reduce carbon emissions from a VPP. After the electric boiler is considered in the VPP operation model of the combined heat and power system, a multi-objective model is built, which includes the costs of carbon emissions, total operation of the VPP and the electricity traded between the VPP and the main grid. The model is solved by the CPLEX package using the fuzzy membership function in Matlab, and a case study is presented. The power output of each unit in the case study is analyzed under four scenarios. The results show that after carbon emission is taken into account, the output of low carbon units is significantly increased, and the allocation of an electric boiler can facilitate the maximum absorption of renewable energy, which also reduces carbon emissions from the VPP. 展开更多
关键词 Virtual power plant (VPP) Carbon emissions Electric boiler Wind power Combined heat and power (CHP)
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A Fuzzy Negotiation Model of E-commerce
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作者 Yuying Wu Jinxuan Lu 《Journal of Systems Science and Information》 2006年第1期33-37,共5页
We usually decide to accept or reject the offer based on the utility function in the traditional automatic negotiation of E-commerce so that we reject the offers whose utility is lower than a specified value. Here we ... We usually decide to accept or reject the offer based on the utility function in the traditional automatic negotiation of E-commerce so that we reject the offers whose utility is lower than a specified value. Here we evaluate the acceptability based on the fuzzy set theory and the membership function. Since different issues have different effect on the negotiators, we state the combined concession in the multi-issue negotiation for the negotiators. We put forward a more practical negotiation model than the traditional negotiation model and give an example of its application in E-commerce. 展开更多
关键词 E-commerce fuzzy math. AGENT the membership function automatic negotiation
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