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Generalized ordered weighted averaging operators based methods for MADM in intuitionistic fuzzy set setting 被引量:4
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作者 Wang Shuqi Li Dengfeng Wu Zhiqian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1247-1254,共8页
Multiattribute decision making(MADM) problems, in which the weights and ratings of alternatives are expressed with intuitionistic fuzzy(IF) sets, are investigated.Firstly, the relative degrees of membership and th... Multiattribute decision making(MADM) problems, in which the weights and ratings of alternatives are expressed with intuitionistic fuzzy(IF) sets, are investigated.Firstly, the relative degrees of membership and the relative degrees of non-membership are formulated as IF sets, the weights and values of alternatives on both qualitative and quantitative attributes may be expressed as IF sets in a unified way.Then a MADM method based on generalized ordered weighted averaging operators is proposed.The proposed method is illustrated with a numerical example. 展开更多
关键词 multiattribute decision making intuitionistic fuzzy set ordered weighted averaging operator fuzzy set.
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Linear goal programming approach to obtaining the weights of intuitionistic fuzzy ordered weighted averaging operator 被引量:3
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作者 Yejun Xu Chao Huang +1 位作者 Qingli Da Xinwang Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期990-994,共5页
The multiple attribute decision making problems are studied, in which the information about attribute weights is partly known and the attribute values take the form of intuitionistic fuzzy numbers. The operational law... The multiple attribute decision making problems are studied, in which the information about attribute weights is partly known and the attribute values take the form of intuitionistic fuzzy numbers. The operational laws of intuitionistic fuzzy numbers are introduced, and the score function and accuracy function are presented to compare the intuitionistic fuzzy numbers. The intuitionistic fuzzy ordered weighted averaging (IFOWA) operator which is an extension of the well-known ordered weighted averaging (OWA) operator is investigated to aggregate the intuitionistic fuzzy information. In order to determine the weights of intuitionistic fuzzy ordered weighted averaging operator, a linear goal programming procedure is proposed for learning the weights from data. Finally, an example is illustrated to verify the effectiveness and practicability of the developed method. 展开更多
关键词 intuitionistic fuzzy set intuitionistic fuzzy ordered weighted averaging(IFOWA) operator linear goal programming WEIGHTS multiple attribute decision making(MADM).
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Fast acquisition of L2C CL codes based on combination of hyper codes and averaging correlation 被引量:1
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作者 Qingxi Zeng Linlin Tang +1 位作者 Pengna Zhang Ling Pei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期308-318,共11页
This paper provides a direct and fast acquisition algorithm of civilian long length(CL) codes in the L2 civil(L2C) signal. The proposed algorithm simultaneously reduces the number of fast Fourier transformation(... This paper provides a direct and fast acquisition algorithm of civilian long length(CL) codes in the L2 civil(L2C) signal. The proposed algorithm simultaneously reduces the number of fast Fourier transformation(FFT) correlation through hyper code technique and the amount of points in every FFT correlation by using an averaging correlation method. To validate the proposed acquisition performance, the paper applies this algorithm to the real L2C signal collected by the global positioning system(GPS) L2C intermediate frequency(IF) signal sampler—SIS100L2C. The acquisition results show that the proposed modified algorithm can acquire the code phase accurately with less calculation and its acquisition performance is better than the single hyper code method. 展开更多
关键词 L2C civilian long length(CL) code fast acquisition hyper code averaging correlation
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Simulation of light environment in a serrated photovoltaic greenhouse and optimization of daylighting roofs based on Design Builder
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作者 LIU Jian WU Xuyong +2 位作者 WANG Baolong WU Qingsen TIAN Libo 《农业工程学报》 北大核心 2025年第7期211-221,共11页
In the tropical regions represented by Hainan,there are abundant solar and thermal resources,and it is relatively suitable for the construction of photovoltaic greenhouse(PVG).However,the construction of PVG still rel... In the tropical regions represented by Hainan,there are abundant solar and thermal resources,and it is relatively suitable for the construction of photovoltaic greenhouse(PVG).However,the construction of PVG still relies mainly on experience and is incapable of quantifying the balance between the photovoltaic(PV)generation and the light requirements for agricultural production.As a result,actual PVGs are primarily PV-based,without carefully considering the needs of agricultural daylighting.To quantify the influence of the design parameters of PVGs and the layout of PV panels on the internal daylighting of serrated PVGs,and to optimize the daylighting design of the roof,this paper utilizes the Design Builder software to establish gradient models for a multi-span serrated-type PVG in tropical regions.Gradient models were established in terms of aspects,namely span,width of longitudinal/transverse daylighting strip,height,roof angle,and photovoltaic panel coverage rate(PCR).Daylighting in the greenhouse of each gradient model was simulated,and with the annual average daily light integral(A_(DLI))and distribution uniformity(DU)as evaluation indicators,the influence of various design parameters on the daylighting inside the greenhouse was quantified.The result reveals that:(1)PCR is the decisive indicator for daylighting in the PVG,and a function between PCR and the A_(DLI) is derived as A_(DLI)=-15.5 PCR+16.841;(2)Increasing the width of longitudinal daylighting strip significantly improves the A_(DLI) and enhances DU while increasing the span has a noticeable effect on improving A_(DLI) but does not significantly enhance DU;(3)Increasing the eave height without changing PCR does not enhance A_(DLI) but effectively improves DU;increasing the transverse daylighting strip and adjusting the roof angle hardly improves A_(DLI).In summary,it is recommended that the optimal span for PVGs in tropical regions be set within the range of 6.5-8.0m,and the eave height be set within the range of 2.5-3.5m.Preferably,the longitudinal daylighting strip with a width ranging from 0.5-0.8m should be installed.Based on the above relationship function,the PCR can be calculated according to the appropriate light demand for the cultivated crops.The daylighting design theory proposed in this paper can provide a theoretical basis and reference for the healthy development of the PV industry in tropical regions. 展开更多
关键词 photovoltaic greenhouse annual average daily light integral greenhouse design parameters DAYLIGHTING tropical regions
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Gender differences in the burden of near vision loss in China:An analysis based on GBD 2021 data
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作者 LIU Yu ZHU Liping +4 位作者 LIN Yanhui WANG Yanbing XIONG Kun LI Xuhong YAN Wenguang 《中南大学学报(医学版)》 北大核心 2025年第6期1030-1041,共12页
Objective:Near vision loss(NVL)is one of the leading causes of visual impairment worldwide,exerting a profound impact on individual quality of life and socio-economic development.This study aims to analyze the burden ... Objective:Near vision loss(NVL)is one of the leading causes of visual impairment worldwide,exerting a profound impact on individual quality of life and socio-economic development.This study aims to analyze the burden of NVL in China by sex and age groups from 1990 to 2021 and to project trends over the next 15 years.Methods:Using data from the Global Burden of Disease(GBD)2021 database,we conducted descriptive analyses of NVL prevalence in China,calculated age-standardized prevalence rates(ASPR)and age-standardized disability-adjusted life years rates(ASDR)to compare burden differences between sexes and age groups,and applied an autoregressive integrated moving average(ARIMA)model to predict NVL trends for the next 15 years.The model selection was based on best-fit criteria to ensure reliable projections.Results:From 1990 to 2021,China’s ASPR of NVL rose from 10096.24/100000 to 15624.54/100000,and ASDR increased from 101.75/100000 to 158.75/100000.In 2021,ASPR(16551.70/100000)and ASDR(167.69/100000)were higher among females than males(14686.21/100000 and 149.76/100000,respectively).China ranked highest globally in both NVL cases and disability-adjusted life years(DALYs),with female burden significantly exceeding male burden.Projections indicated this trend and sex gap will persist until 2036.Compared with 1990,the prevalence cases and DALYs increased by 239.20%and 238.82%,respectively in 2021,with the highest burden among females and the 55−59 age group.The ARIMA model predicted continued increases in prevalence and DALYs by 2036,with females maintaining a higher burden than males.Conclusion:This study reveals a marked increase in the NVL burden in China and predicts continued growth in the coming years.Public health policies should prioritize NVL prevention and control,with special attention to women and middle-aged populations to mitigate long-term societal and health impacts. 展开更多
关键词 China near vision loss Global Burden of Disease database autoregressive integrated moving average model gender differences
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Fixed-time distributed average consensus tracking for multiple Euler-Lagrange systems
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作者 SUN Guhao ZENG Qingshuang CAI Zhongze 《Journal of Systems Engineering and Electronics》 2025年第2期523-536,共14页
This paper investigates the sliding-mode-based fixed-time distributed average tracking (DAT) problem for multiple Euler-Lagrange systems in the presence of external distur-bances. The primary objective is to devise co... This paper investigates the sliding-mode-based fixed-time distributed average tracking (DAT) problem for multiple Euler-Lagrange systems in the presence of external distur-bances. The primary objective is to devise controllers for each agent, enabling them to precisely track the average of multiple time-varying reference signals. By averaging these signals, we can mitigate the influence of errors and uncertainties arising dur-ing measurements, thereby enhancing the robustness and stabi-lity of the system. A distributed fixed-time average estimator is proposed to estimate the average value of global reference sig-nals utilizing local information and communication with neigh-bors. Subsequently, a fixed-time sliding mode controller is intro-duced incorporating a state-dependent sliding mode function coupled with a variable exponent coefficient to achieve dis-tributed average tracking of reference signals, and rigorous ana-lytical methods are employed to substantiate the fixed-time sta-bility. Finally, numerical simulation results are provided to vali-date the effectiveness of the proposed methodology, offering insights into its practical application and robust performance. 展开更多
关键词 distributed average tracking(DAT) fixed-time con-vergence Euler-Lagrange systems sliding mode control
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Asynchronously fault detection for flight vehicles with unstable modes via MDLF and MDADT method
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作者 Sheng Luo Xin Liu +2 位作者 Yanfei Cheng Shiyu Shuai Haoyu Cheng 《Defence Technology(防务技术)》 2025年第7期417-436,共20页
This research focuses on detecting faults in flight vehicles with unstable subsystems operating asynchronously.By accounting for asynchronous switching,a switched model is established,and filters for fault detection(F... This research focuses on detecting faults in flight vehicles with unstable subsystems operating asynchronously.By accounting for asynchronous switching,a switched model is established,and filters for fault detection(FD)in unstable subsystems are developed.The FD challenge is then transformed into an H∞filtering issue.Utilizing the multiple discontinuous Lyapunov function(MDLF)approach and the mode-dependent average dwell time(MDADT)method,sufficient conditions are derived to ensure stability during both fast and slow switching.Furthermore,the existence and solutions for FD filters are provided through linear matrix inequalities(LMIs).The simulation outcomes demonstrated the excellent performance of the developed method in studied cases. 展开更多
关键词 Fault detection Asynchronous switching H∞filtering Multiple discontinuous lyapunov function Mode-dependent average dwell time Linear matrix inequalities(LMIs)
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黑龙江桦南地区黑龙江杂岩锆石U-Pb定年 被引量:30
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作者 李旭平 焦丽香 +3 位作者 郑庆道 董晓 孔凡梅 宋召军 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第8期1909-1916,共8页
黑龙江杂岩主要由绿片岩相变质岩和糜棱岩化构造片岩组成,长期以来与麻山杂岩一起被认为代表佳木斯地块的前寒武纪基底,但这种认识缺乏可信的同位素年代学及古生物资料的支持。对出露于黑龙江省东部桦南地区湖南营组绿片岩进行了锆石LA-... 黑龙江杂岩主要由绿片岩相变质岩和糜棱岩化构造片岩组成,长期以来与麻山杂岩一起被认为代表佳木斯地块的前寒武纪基底,但这种认识缺乏可信的同位素年代学及古生物资料的支持。对出露于黑龙江省东部桦南地区湖南营组绿片岩进行了锆石LA-ICP-MS U-Pb定年研究。结果显示锆石的Th/U比值为0.27~1.27,变化较大;获得两组^(206)Ph/^(238)U年龄数据:其加权平均年龄分别为:511±10Ma(n=13,MSWD=1.6)和274.7±3.6Ma(n=9,MSWD=0.91)。黑龙江杂岩中最老的年龄969~747Ma表现来自中元古和新元古代。这些年龄与黑龙江杂岩的年龄与来自俯冲碰撞变质事件的~511Ma的年龄结合起来,表明黑龙江杂岩中含有经历晚新元古——早古生代造山作用的碎屑锆石,亦或代表着在俯冲拼贴过程中混入的麻山杂岩块体。~275Ma年龄反映黑龙江杂岩经历的一次碰撞造山事件,可能与晚古生代古亚洲洋闭合相关。 展开更多
关键词 黑龙江省 桦南 地区 麻山杂岩 碎屑锆石 U-Pb定年 complex zircon dating weighted average ages METAMORPHIC age 同位素年代学 前寒武纪基底 碰撞造山事件 绿片岩相 古亚洲洋闭合 佳木斯地块 造山作用 早古生代 新元古代
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ECMWF集合预报和确定性预报对淮河流域暴雨预报的对比分析 被引量:25
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作者 董全 金荣花 +1 位作者 代刊 康志明 《气象》 CSCD 北大核心 2016年第9期1146-1153,共8页
本文运用2012年5—9月欧洲中期天气预报中心(ECMWF)的集合预报系统(Ensemble Prediction System,EPS)和确定性模式(High-resolution Deterministic forecast,HDet)资料对比分析了淮河流域暴雨的预报效果。对于集合预报,主要对比了基于EP... 本文运用2012年5—9月欧洲中期天气预报中心(ECMWF)的集合预报系统(Ensemble Prediction System,EPS)和确定性模式(High-resolution Deterministic forecast,HDet)资料对比分析了淮河流域暴雨的预报效果。对于集合预报,主要对比了基于EPS的日降水量极端天气预报指数(Extreme Forecast Index,EFI),和改进的贝叶斯模型平均(Modified Bayesian Model Averaging,MBMA)法对降水的订正后概率。由于ROC(Relative Operating Characteristic)检验是与模式的系统性偏差无关的,所以选用ROC检验,对比了不同空报率下的TS评分,以及不同方法的相对经济价值。对比检验的结果显示,各时效预报MBMA预报效果最好,其次是HDet,EFI的预报效果最差,其中2 d内的预报HDet接近MBMA,随着预报时效的延长,MBMA相对于HDet和EFI的优势不断增强。在不同标准下确定三种方法对淮河流域暴雨预报的阈值,结果显示MBMA同样优于HDet,EFI预报效果最差。但MBMA的优势是通过增加预报偏差得到,如果将预报偏差限定为主观预报的1.37,此时MBMA的效果和HDet的效果接近。 展开更多
关键词 集合预报系统(Ensemble Prediction System EPS) 改进型贝叶斯模型平均(Modified Bayesian Model averaging MBMA) 极端预报指数(Extreme Forecast Index EFI) 暴雨
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传感器网络中过滤机制下高效top-k查询处理技术 被引量:2
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作者 张慧 郑吉平 韩秋廷 《小型微型计算机系统》 CSCD 北大核心 2014年第1期44-49,共6页
如何能量高效的进行top-k查询处理是无线传感器网络领域中的一个重要课题.节点设置过滤窗口可以避免与top-k查询无关的数据上传到汇聚节点或者基站,因而大大减少传感器网络的通信量,节省传感器节点能量.然而,已有算法如FILA、DAFM,基站... 如何能量高效的进行top-k查询处理是无线传感器网络领域中的一个重要课题.节点设置过滤窗口可以避免与top-k查询无关的数据上传到汇聚节点或者基站,因而大大减少传感器网络的通信量,节省传感器节点能量.然而,已有算法如FILA、DAFM,基站到传感器节点的过滤窗口更新中仍然存在很大开销.提出一种基于预测信息更新窗口的top-k查询算法FAPU,该算法根据历史数据采用ARIMA时间序列预测模型对接下来s个时刻的传感器数据进行预测,根据预测信息进行多步窗口更新的代价评估,避免不必要的窗口更新,从而减小窗口更新的能量消耗.实验结果表明在确保top-k查询准确性的同时,本文所提出的FAPU算法与已有算法相比更加能量有效. 展开更多
关键词 无线传感器网络 TOP-K Filter-based Monitoring Approach(FILA) 时间序列 AUTOREGRESSIVE Integrated Moving AVERAGE (ARIMA)
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一个计算超滤膜平均孔径的新公式 被引量:1
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作者 丁马太 何旭敏 余乃梅 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1991年第5期546-548,共3页
膜的平均孔径是多孔性分离膜的重要参数。因此,它的准确测定有着重要意义。目前,通常采用的有哈根-泊肃叶(Hagen-Poiseuille)法和扫描电镜(SEM)法。哈根-泊肃叶法主要依据是泊肃叶定律。假设所有膜孔都是垂直于膜面、半径相等的圆形直... 膜的平均孔径是多孔性分离膜的重要参数。因此,它的准确测定有着重要意义。目前,通常采用的有哈根-泊肃叶(Hagen-Poiseuille)法和扫描电镜(SEM)法。哈根-泊肃叶法主要依据是泊肃叶定律。假设所有膜孔都是垂直于膜面、半径相等的圆形直管。此时,膜孔长度1可取膜厚度的值。当膜的孔密度为n、膜两侧工作压差为Δp时,则粘滞系数为η的液体在t时间内透过工作面积为A的多孔膜的体积流量Q与膜孔半径r有如下关系: 展开更多
关键词 AVERAGE PORE size of UF membrane SEM method Hagen-Poiseuille LAW
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Entropy-based procedures for intuitionistic fuzzy multiple attribute decision making 被引量:7
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作者 Xu Zeshui~(1,2) & Hu Hui~3 1.School of Economics and Management,Southeast Univ.,Nanjing 210096,P.R.China 2.Inst.of Sciences,PLA Univ.of Sciences and Technology,Nanjing 210007,P.R.China 3.Inst.of Communications Engineering,PLA Univ.of Sciences and Technology, Nanjing 210007,P.R.China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期1001-1011,共11页
The class of multiple attribute decision making (MADM) problems is studied, where the attribute values are intuitionistic fuzzy numbers, and the information about attribute weights is completely unknown. A score fun... The class of multiple attribute decision making (MADM) problems is studied, where the attribute values are intuitionistic fuzzy numbers, and the information about attribute weights is completely unknown. A score function is first used to calculate the score of each attribute value and a score matrix is constructed, and then it is transformed into a normalized score matrix. Based on the normalized score matrix, an entropy-based procedure is proposed to derive attribute weights. Furthermore, the additive weighted averaging operator is utilized to fuse all the normalized scores into the overall scores of alternatives, by which the ranking of all the given alternatives is obtained. This paper is concluded by extending the above results to interval-valued intuitionistic fuzzy set theory, and an illustrative example is also provided. 展开更多
关键词 multiple attribute decision making intuitionistic fuzzy number score matrix ENTROPY additive weighted averaging operator.
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Consensus intuitionistic fuzzy group decision-making method for aircraft cockpit display and control system evaluation 被引量:6
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作者 Tao Geng An Zhang Guangshan Lu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第4期634-641,共8页
A novel group decision-making (GDM) method based on intuitionistic fuzzy sets (IFSs) is developed to evaluate the ergonomics of aircraft cockpit display and control system (ACDCS). The GDM process with four step... A novel group decision-making (GDM) method based on intuitionistic fuzzy sets (IFSs) is developed to evaluate the ergonomics of aircraft cockpit display and control system (ACDCS). The GDM process with four steps is discussed. Firstly, approaches are proposed to transform four types of common judgement representations into a unified expression by the form of the IFS, and the features of unifications are analyzed. Then, the aggregation operator called the IFSs weighted averaging (IFSWA) operator is taken to synthesize decision-makers’ (DMs’) preferences by the form of the IFS. In this operator, the DM’s reliability weights factors are determined based on the distance measure between their preferences. Finally, an improved score function is used to rank alternatives and to get the best one. An illustrative example proves the proposed method is effective to valuate the ergonomics of the ACDCS. 展开更多
关键词 aircraft cockpit display and control system (ACDCS) group decision-making (GDM) intuitionistic fuzzy set (IFS) different preference representation weighted averaging (WA) operator.
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Interval-valued intuitionistic fuzzy aggregation operators 被引量:4
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作者 Weize Wang Xinwang Liu Yong Qin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第4期574-580,共7页
The notion of the interval-valued intuitionistic fuzzy set (IVIFS) is a generalization of that of the Atanassov's intuitionistic fuzzy set. The fundamental characteristic of IVIFS is that the values of its membersh... The notion of the interval-valued intuitionistic fuzzy set (IVIFS) is a generalization of that of the Atanassov's intuitionistic fuzzy set. The fundamental characteristic of IVIFS is that the values of its membership function and non-membership function are intervals rather than exact numbers. There are various averaging operators defined for IVlFSs. These operators are not monotone with respect to the total order of IVIFS, which is undesirable. This paper shows how such averaging operators can be represented by using additive generators of the product triangular norm, which simplifies and extends the existing constructions. Moreover, two new aggregation operators based on the t.ukasiewicz triangular norm are proposed, which are monotone with respect to the total order of IVIFS. Finally, an application of the interval-valued intuitionistic fuzzy weighted averaging operator is given to multiple criteria decision making. 展开更多
关键词 interval-valued intuitionistic fuzzy set (IVIFS) interval-valued intuitionistic fuzzy weighted averaging (IVlFWA) operator interval-valued intuitionistic fuzzy ordered weighted averaging (IVI-FOWA) operator multiple criteria decision making (MCDM) mono-tonicity.
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Generalization of the linguistic aggregation operator and its application in decision making 被引量:3
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作者 Jose M. Merigo Anna M. Gil-Lafuente +1 位作者 Ligang Zhou Huayou Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期593-603,共11页
A generalization of the linguistic aggregation functions (or operators) is presented by using generalized and quasiarithmetic means. Firstly, the linguistic weighted generalized mean (LWGM) and the linguistic gene... A generalization of the linguistic aggregation functions (or operators) is presented by using generalized and quasiarithmetic means. Firstly, the linguistic weighted generalized mean (LWGM) and the linguistic generalized ordered weighted averaging (LGOWA) operator are introduced. These aggregation functions use linguistic information and generalized means in the weighted average (WA) and in the ordered weighted averaging (OWA) function. They are very useful for uncertain situations where the available information cannot be assessed with numerical values but it is possible to use linguistic assessments. These aggregation operators generalize a wide range of aggregation operators that use linguistic information such as the linguistic generalized mean (LGM), the linguistic OWA (LOWA) operator and the linguistic or- dered weighted quadratic averaging (LOWQA) operator. We also introduce a further generalization by using quasi-arithmetic means instead of generalized means obtaining the quasi-LWA and the quasi-LOWA operator. Finally, we develop an application of the new approach where we analyze a decision making problem regarding the selection of strategies. 展开更多
关键词 linguistic aggregation function linguistic orderedweighted averaging (OWA) operator generalized mean linguis-tic decision making strategic decision making uncertainty.
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基于改进的双极Slope One算法的农业信息推荐模型研究 被引量:1
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作者 张启宇 宋瑶 +1 位作者 陈英义 封文杰 《安徽农业科学》 CAS 2014年第29期10394-10396,共3页
为了在海量信息中为用户提供有价值的信息,个性化在线推荐系统是农业信息化综合服务平台的重要组成部分。Slope One算法因简单高效被许多在线推荐系统使用。对Slope One算法进行研究,并结合农业信息化综合服务平台的特点,提出了农业信... 为了在海量信息中为用户提供有价值的信息,个性化在线推荐系统是农业信息化综合服务平台的重要组成部分。Slope One算法因简单高效被许多在线推荐系统使用。对Slope One算法进行研究,并结合农业信息化综合服务平台的特点,提出了农业信息推荐模型。该模型按资源类别把用户评分矩阵划分为评分子矩阵,在此基础上采用杰卡德统一算子距离相似度算法建立用户类别近邻用户,采用改进的双极Slope One算法和Item user average算法相结合的方式对未访问资源进行评分预测,有效降低计算量,并提高了评分预测精度,既适合稠密数据集,又适合稀疏数据集。 展开更多
关键词 杰卡德统一算子距离相似度算法 双极Slope one算法 ITEM user average算法 农业信息 个性化推荐
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Inertial projection algorithms for convex feasibility problem 被引量:2
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作者 Yazheng Dang Yan Gao Lihua Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期734-740,共7页
The purpose of this paper is to apply inertial technique to string averaging projection method and block-iterative projection method in order to get two accelerated projection algorithms for solving convex feasibility... The purpose of this paper is to apply inertial technique to string averaging projection method and block-iterative projection method in order to get two accelerated projection algorithms for solving convex feasibility problem.Compared with the existing accelerated methods for solving the problem,the inertial technique employs a parameter sequence and two previous iterations to get the next iteration and hence improves the flexibility of the algorithm.Theoretical asymptotic convergence results are presented under some suitable conditions.Numerical simulations illustrate that the new methods have better convergence than the general projection methods.The presented algorithms are inspired by the inertial proximal point algorithm for finding zeros of a maximal monotone operator. 展开更多
关键词 convex feasibility problem inertial technique string averaging block iteration asymptotic convergence
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Data envelopment analysis procedure with two non-homogeneous DMU groups 被引量:2
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作者 CHEN Ye WU Liangpeng LU Bo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期780-788,共9页
The classic data envelopment analysis(DEA) model is used to evaluate decision-making units'(DMUs) efficiency under the assumption that all DMUs are evaluated with the same criteria setting. Recently, new research... The classic data envelopment analysis(DEA) model is used to evaluate decision-making units'(DMUs) efficiency under the assumption that all DMUs are evaluated with the same criteria setting. Recently, new researches begin to focus on the efficiency analysis of non-homogeneous DMU arose by real practices such as the evaluation of departments in a university, where departments argue for the adoption of different criteria based on their disciplinary characteristics. A DEA procedure is proposed in this paper to address the efficiency analysis of two non-homogeneous DMU groups. Firstly, an analytical framework is established to compromise diversified input and output(IO) criteria from two nonhomogenous groups. Then, a criteria fusion operation is designed to obtain different DEA analysis strategies. Meanwhile, Friedman test is introduced to analyze the consistency of all efficiency results produced by different strategies. Next, ordered weighted averaging(OWA) operators are applied to integrate different information to reach final conclusions. Finally, a numerical example is used to illustrate the proposed method. The result indicates that the proposed method relaxes the restriction of the classical DEA model,and can provide more analytical flexibility to address different decision analysis scenarios arose from practical applications. 展开更多
关键词 data envelopment analysis (DEA) non-homogeneousdecision-making unit (DMU) criteria fusion Friedman test ordered weighted averaging (OWA) operator
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基于ARIMA模型对上证指数的预测 被引量:10
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作者 白营闪 《科学技术与工程》 2009年第16期4885-4888,共4页
股票价格涉及很多不确定因素,且各个因素之间的相关关系错综复杂,因此要从理论上彻底弄清楚股市的变化机理十分困难。然而股市是一个运动的、特殊的系统,它必然存在着规律。以上证综合指数为例,利用EVIEWS软件对其股票价格建立ARIMA模型... 股票价格涉及很多不确定因素,且各个因素之间的相关关系错综复杂,因此要从理论上彻底弄清楚股市的变化机理十分困难。然而股市是一个运动的、特殊的系统,它必然存在着规律。以上证综合指数为例,利用EVIEWS软件对其股票价格建立ARIMA模型,提出了股票价格序列的一步向前静态预测方法,用于股票价格序列的建模及股价短期预测,希望为企业和投资者在进行相关决策时提供有益的参考。 展开更多
关键词 上证综合指数 自回归移动平均模型(Autoregressive Integrated Moving Average Model ARIMA模型) 计量经济学 观察(Econometrics VIEWS EVIEWS)
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Progressive failure analysis of composite structure based on micro- and macro-mechanics models 被引量:1
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作者 孙志刚 阮绍明 +1 位作者 陈磊 宋迎东 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2980-2988,共9页
Based on parameter design language, a program of progressive failure analysis in composite structures is proposed. In this program, the relationship between macro- and micro-mechanics is established and the macro stre... Based on parameter design language, a program of progressive failure analysis in composite structures is proposed. In this program, the relationship between macro- and micro-mechanics is established and the macro stress distribution of the composite structure is calculated by commercial finite element software. According to the macro-stress, the damaged point is found and the micro-stress distribution of representative volume element is calculated by finite-volume direct averaging micromechanics(FVDAM). Compared with the results calculated by failure criterion based on macro-stress field(the maximum stress criteria and Hashin criteria) and micro-stress field(Huang model), it is proven that the failure analysis based on macro- and micro-mechanics model is feasible and efficient. 展开更多
关键词 composite progressive analysis finite-volume direct averaging micromechanics (FVDAM) failure criteria
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