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Xu Z.,Shanghai JiaoTong University | Xu Z.,PLA University of Science and Technology
Information Sciences | Year: 2010

The Choquet integral is a very useful way of measuring the expected utility of an uncertain event [G. Choquet, Theory of capacities, Annales de l'institut Fourier 5 (1953) 131-295]. In this paper, we use the Choquet integral to propose some intuitionistic fuzzy aggregation operators. The operators not only consider the importance of the elements or their ordered positions, but also can reflect the correlations among the elements or their ordered positions. It is worth pointing out that most of the existing intuitionistic fuzzy aggregation operators are special cases of our operators. Moreover, we propose the interval-valued intuitionistic fuzzy correlated averaging operator and the interval-valued intuitionistic fuzzy correlated geometric operator to aggregate interval-valued intuitionistic fuzzy information, and apply them to a practical decision-making problem involving the prioritization of information technology improvement projects. © 2009 Elsevier Inc. All rights reserved.

Zhu B.,Nanjing Southeast University | Xu Z.,PLA University of Science and Technology
IEEE Transactions on Fuzzy Systems | Year: 2014

Hesitant fuzzy linguistic term sets (HFLTSs) are used to deal with situations in which the decision makers (DMs) think of several possible linguistic values or richer expressions than a single term for an indicator, alternative, variable, etc. Compared with fuzzy linguistic approaches, they are more convenient and flexible to reflect the DMs' preferences in decision making. For further applications of HFLTSs to decision making, we develop a concept of hesitant fuzzy linguistic preference relations (HFLPRs) as a tool to collect and present the DMs' preferences. Due to the importance of the consistency measures using preference relations in decision making, we develop some consistency measures for HFLPRs to ensure that the DMs are being neither random nor illogical. A consistency index is defined to establish the consistency thresholds of HFLPRs to measure whether an HFLPR is of acceptable consistency. For HFLPRs with unacceptable consistency, we develop two optimization methods to improve the consistency until they are acceptable. Several illustrative examples are given to validate the consistency measures and the optimization methods. © 2013 IEEE.

Xu Z.,PLA University of Science and Technology
IEEE Transactions on Fuzzy Systems | Year: 2013

An intuitionistic multiplicative preference relation was recently introduced by Xia et al. to characterize the preference information that is given by a decision maker over a set of objects. All the elements of the intuitionistic multiplicative preference relation are the 2-tuples, which can simultaneously depict the degree that one object is prior to another, and the degree that the object is not prior to another. Each part of the 2-tuples takes its value from the closed interval [1/9, 9], and thus can describe the decision maker's preferences over objects more comprehensively than the traditional multiplicative preference relation. How to derive the priority weights of the objects from an intuitionistic multiplicative preference relation is an important research topic for decision making with intuitionistic multiplicative preference information. In this paper, we shall focus on solving this issue. We first define the concepts of expected intuitionistic multiplicative preference relation, left and right error matrices, etc. Then based on the geometric aggregation operator and the error propagation formula, we derive the priority weight intervals from an intuitionistic multiplicative preference relation. After that, some approaches to decision making based on intuitionistic multiplicative preference relations are developed, and furthermore, two practical examples are given to illustrate our approaches. © 1993-2012 IEEE.

Qian Q.-H.,PLA University of Science and Technology
Yantu Lixue/Rock and Soil Mechanics | Year: 2014

As a review paper, the discourses on the mechanism and the definition of rockburst of authoritative experts were quoted, based on these discourses and according to the different mechanisms of rockburst, rockbursts are divided into the sliding mode rockburst resulting from fault-slip events and strain mode rockburst resulting from the failure of the rock. Combined with the specific accident cases, the mechanism and characteristics of the two types of rockburst are analyzed. Finally, based on the analysis of the mechanism, the quantitative forecast and numerical simulation of rock (coal) pillar strain mode rockburst, enclosing rock strain mode rockburst and sliding mode rockburst are introduced, in which, the author's latest research of quantitative forecast and numerical simulation for strain mode rockburst after incompatible deformation by using non-Euclidean geometry model is included.

Xu Z.,PLA University of Science and Technology
Knowledge-Based Systems | Year: 2012

Intuitionistic fuzzy preference relation is a suitable tool used to describe uncertain or vague preference information provided by a decision maker in fuzzy decision making situations. A key step in decision making with an intuitionistic preference relation is to derive the priority vector of the intuitionistic preference relation. In this paper, we develop an error-analysis-based method for the priority of an intuitionistic preference relation, and then a possibility degree formula is used to derive the ranking of the considered alternatives. Moreover, a numerical analysis on the developed method is conducted through an illustrative example. © 2012 Elsevier B.V. All rights reserved.

Qian Q.,PLA University of Science and Technology
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2012

The status quo of safety management in China's underground projects construction was introduced. Based on the accidents statistics, the serious security situation of underground projects construction was certificated. The analysis of types and causes for accidents indicated that the responsibility and subjective reasons are the great challenges for security management. Combining with Hain's safety pyramid theory, Heinrich's safety rules and Johnson's changes-errors model, the concept that accidents can be prevented by risk management measures was established, and some suggestions for accidents prevention were put forward. Besides, the mechanism and control measures for two typical geological hazards, i.e. water and mud outbursts and rockburst, were represented. For the study of water and mud outbursts, the laws of occurrence and development, the precursory information theory, the geological prediction methods and other incident countermeasures were introduced. For the control measures of rockburst, the definition and classification of rockbursts, the prevention mechanism, theoretical basis and engineering practice for monitoring and prediction, as well as the construction measures, were introduced. Some opinions and suggestions on technical methods and management tools were put forward for the accident prevention for underground projects construction.

Xu Z.,PLA University of Science and Technology
Computers and Industrial Engineering | Year: 2013

In group decision making under uncertainty, interval preference orderings as a type of simple uncertain preference structure, can be easily and conveniently used to express the experts' evaluations over the considered alternatives. In this paper, we investigate group decision making problems with interval preference orderings on alternatives. We start by fusing all individual interval preference orderings given by the experts into the collective interval preference orderings through the uncertain additive weighted averaging operator. Then we establish a nonlinear programming model by minimizing the divergences between the individual uncertain preferences and the group's opinions, from which we derive an exact formula to determine the experts' relative importance weights. After that, we calculate the distances of the collective interval preference orderings to the positive and negative ideal solutions, respectively, based on which we use a TOPSIS based approach to rank and select the alternatives. All these results are also reduced to solve group decision making problems where the experts' evaluations over the alternatives are expressed in exact preference orderings. A numerical analysis of our model and approach is finally carried out using two illustrative examples. © 2013 Published by Elsevier Ltd.

A method and video sensor for precipitation microphysical features measurement based on particle image velocimetry. The CCD camera is placed facing towards the light source, which forms a three-dimensional sampling space. As the precipitation particles fall through the sampling space, double-exposure images of precipitation particles illuminated by pulse light source are recorded by CCD camera. Combined with the telecentric imaging system, the time between the two exposures are adaptive and can be adjusted according to the velocity of precipitation particles. The size and shape can be obtained by the images of particles; the fall velocity can be calculated by particle displacement in the double-exposure image and interval time; the drop size distribution and velocity distribution, precipitation intensity, and accumulated precipitation amount can be calculated by time integration. This invention provides a method for measuring the shape, size, velocity, and other microphysical characteristics of various precipitation particles.

PLA University of Science and Technology | Date: 2011-06-30

The invention relates to a cognitive SIMO network access method based on cooperative relay, wherein a cognitive base station collects channel responses in a network and judges whether the cognitive users can cooperate with a primary user to achieve the target transmission rate required by the primary user or not, if so, a cognitive SIMO network is accessible to a frequency band licensed to the primary user; otherwise, the cognitive SIMO network is non-accessible. The access method can enable a plurality of the cognitive users and the primary user to simultaneously use the same licensed spectrum in the same geographical position, on the premise of ensuring the target transmission rate of the primary user, and further improve the utilization efficiency of the spectrum as far as possible. As the access method is based on cooperative communication, the nearer the distance from the cognitive network to the primary network is, the greater the network throughput can be achieved; and furthermore, a large-range network coverage can be realized, so the deficiencies in the existing cognitive radio access ways are made up.

PLA University of Science and Technology | Date: 2011-06-30

The invention relates to a resource distribution method for throughput maximization in a cooperative cognitive SIMO network. The primary user sends data after receiving a cooperation confirmation message, and the cognitive network keeps silence, receives the information data of the primary user and simultaneously decodes the data. The cognitive users which successfully decode the data utilize part of their transmission power to send the data of themselves to the cognitive base station, the remaining transmission power is used for helping in forwarding the data of the primary user; the cognitive users which cannot successfully decode the data only send the data of themselves and do not forward the data of the primary user. The cognitive base station eliminates the interference of the data of primary user in the received mixed signals and performs beamforming on the signals after eliminating the interference. According to the combined adjustment of the transmission power vector, the power distribution factor vector and the beamforming weight vectors of the cognitive SIMO network, the maximum throughput performance can be realized in the cognitive network while the target transmission rate of the primary user is ensured, furthermore, very fast convergence rate can be realized in the proposed resource distribution method.

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