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基于特征分析算法的变换域通信系统接收技术 被引量:2
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作者 宋波 何世彪 +1 位作者 隋静文 甘文道 《太赫兹科学与电子信息学报》 2017年第3期395-401,共7页
异步条件下对变换域通信系统(TDCS)信号用特征值分解法可估计基函数序列,但由于协方差矩阵特征分解的不唯一性,造成分段得到的特征向量存在标量模糊的缺陷。通过理论分析特征值分解算法,提出了一种改进算法,将接收信号的分段周期扩大为... 异步条件下对变换域通信系统(TDCS)信号用特征值分解法可估计基函数序列,但由于协方差矩阵特征分解的不唯一性,造成分段得到的特征向量存在标量模糊的缺陷。通过理论分析特征值分解算法,提出了一种改进算法,将接收信号的分段周期扩大为基函数周期的2倍,通过特征值分解算法得到协方差矩阵的最大特征向量,用长度为基函数周期的窗口在最大特征向量中滑动,当窗口的二范数达到最大值时,即可得到基函数序列。通过实验仿真,改进算法能够有效克服分段向量出现部分正反号的缺陷,系统误码性能与同步条件下的系统误码性能基本一致。 展开更多
关键词 变换域通信系统 基函数 异步条件 标量模糊 特征值分解法 二范数
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A multi-objective fuzzy optimization model for cropping structure and water resources and its method 被引量:3
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作者 马建琴 陈守煜 邱林 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期5-10,共6页
Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this... Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development. 展开更多
关键词 cropping structure multi objective fuzzy optimization fuzzy deciding weight agricultural water resources
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Dynamic Target Wireless Network Selection Technique Using Fuzzy Linguistic Variables 被引量:7
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作者 Faisal Kaleem Abolfazl Mehbodniya +2 位作者 Arif Islam Kang K.Yen Fumiyuki Adachi 《China Communications》 SCIE CSCD 2013年第1期1-16,共16页
Even though various wireless Net- work Access Technologies (NATs) with dif- ferent specifications and applications have been developed in the recent years, no single wireless technology alone can satisfy the any- ti... Even though various wireless Net- work Access Technologies (NATs) with dif- ferent specifications and applications have been developed in the recent years, no single wireless technology alone can satisfy the any- time, anywhere, and any service wire- less-access needs of mobile users. A real seamless wireless mobile environment is only realized by considering vertical and horizontal handoffs together. One of the major design issues in heterogeneous wireless networks is the support of Vertical Handoff (VHO). VHO occurs when a multi-interface enabled mobile terminal changes its Point of Attachment (PoA) from one type of wireless access technology to another, while maintaining an active session. In this paper we present a novel multi-criteria VHO algorithm, which chooses the target NAT based on several factors such as user preferences, system parameters, and traf- tic-types with varying Quality of Service (QoS) requirements. Two modules i.e., VHO Neces- sity Estimation (VHONE) module and target NAT selection module, are designed. Both modules utilize several "weighted" users' and system's parameters. To improve the robust- ness of the proposed algorithm, the weighting system is designed based on the concept of fuzzy linguistic variables. 展开更多
关键词 network access selection VHO heterogeneous networks WLAN WMAN WWAN Techniques for Order Preference bySimilarity to Ideal Solution
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A fuzzy method to learn text classifier from labeled and unlabeled examples
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作者 刘宏 黄上腾 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第1期98-102,共5页
In text classification, labeling documents is a tedious and costly task, as it would consume a lot of expert time. On the other hand, it usually is easier to obtain a lot of unlabeled documents, with the help of some ... In text classification, labeling documents is a tedious and costly task, as it would consume a lot of expert time. On the other hand, it usually is easier to obtain a lot of unlabeled documents, with the help of some tools like Digital Library, Crawler Programs, and Searching Engine. To learn text classifier from labeled and unlabeled examples, a novel fuzzy method is proposed. Firstly, a Seeded Fuzzy c-means Clustering algorithm is proposed to learn fuzzy clusters from a set of labeled and unlabeled examples. Secondly, based on the resulting fuzzy clusters, some examples with high confidence are selected to construct training data set. Finally, the constructed training data set is used to train Fuzzy Support Vector Machine, and get text classifier. Empirical results on two benchmark datasets indicate that, by incorporating unlabeled examples into learning process, the method performs significantly better than FSVM trained with a small number of labeled examples only. Also, the method proposed performs at least as well as the related method-EM with Nave Bayes. One advantage of the method proposed is that it does not rely on any parametric assumptions about the data as it is usually the case with generative methods widely used in semi-supervised learning. 展开更多
关键词 text categorization FUZZY CLUSTERING
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Title Evaluation study of teaching-oriented teaching team in colleges and universities based on analytic hierarchy process
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作者 Meiyun Liu Gaochao Liu 《International English Education Research》 2014年第10期17-20,共4页
You Complying with the school's education purpose of training applied talents, in colleges and universities, teaching-oriented teaching team should be read in conjunction with the construction of its evaluating index... You Complying with the school's education purpose of training applied talents, in colleges and universities, teaching-oriented teaching team should be read in conjunction with the construction of its evaluating index system as well as the improvement of the operation quality of teaching efficiency. In view of vague characteristic of evaluation, this paper uses analytic hierarchy process to carry on the fuzzy and synthetic appraisal for operation quality of teaching-oriented teaching teams in colleges and universities, reasonably ascertaining the weights of the evaluation indexes and improving the objectivity and accuracy of evaluation. 展开更多
关键词 TEACHING-ORIENTED teaching team Analytic Hierarchy Process.
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Determination of the Sets of Sequences with the Standard Fuzzy Metric
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作者 Ugur Kadak 《Journal of Mathematics and System Science》 2013年第5期217-224,共8页
Following George and Veeramani et. al. [On some results in Fuzzy Metric Spaces, Fuzzy Sets Syst. 64 (1994) 395-399], we essentially deal with the classical sequence spaces using of the standard fuzzy metric with t-n... Following George and Veeramani et. al. [On some results in Fuzzy Metric Spaces, Fuzzy Sets Syst. 64 (1994) 395-399], we essentially deal with the classical sequence spaces using of the standard fuzzy metric with t-norm. We consider well-known classical sequence spaces such as l∞ , C, C0 and l p, and we have construct it with standard fuzzy metric. Finally, the completeness of these spaces was given by using the same metric. 展开更多
关键词 Sequence space metric space fuzzy metric space complete metric space.
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