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121.
Dual hesitant fuzzy set (DHFS) is a new generalization of fuzzy set (FS) consisting of two parts (i.e., the membership hesitancy function and the non-membership hesitancy function), which confronts several different possible values indicating the epistemic degrees whether certainty or uncertainty. It encompasses fuzzy set (FS), intuitionistic fuzzy set (IFS), and hesitant fuzzy set (HFS) so that it can handle uncertain information more flexibly in the process of decision making. In this paper, we propose some new operations on dual hesitant fuzzy sets based on Einstein t-conorm and t-norm, study their properties and relationships and then give some dual hesitant fuzzy aggregation operators, which can be considered as the generalizations of some existing ones under fuzzy, intuitionistic fuzzy and hesitant fuzzy environments. Finally, a decision making algorithm under dual hesitant fuzzy environment is given based on the proposed aggregation operators and a numerical example is used to demonstrate the effectiveness of the method. 相似文献
122.
Cascading failures often occur in congested complex networks. Cascading failures can be expressed as a three-phase process:
generation, diffusion, and dissipation of congestion. Different from the betweenness centrality, a congestion function is
proposed to represent the extent of congestion on a given node. Inspired by the restart process of a node, we introduce the
concept of “delay time,” during which the overloaded node cannot receive or forward any traffic, so an intergradation between
permanent removal and nonremoval is built and the flexibility of the presented model is demonstrated. Considering the connectivity
of a network before and after cascading failures is not cracked because the overloaded node are not removed from network permanently
in our model, a new evaluation function of network efficiency is also proposed to measure the damage caused by cascading failures.
Finally, we investigate the effects of network structure and size, delay time, processing ability, and traffic generation
speed on congestion propagation. Cascading processes composed of three phases and some factors affecting cascade propagation
are uncovered as well. 相似文献
123.
A hybrid approach of DEA (data envelopment analysis) and TOPSIS (technique for order performance (preference) by similarity
to ideal solution) is proposed for multiple criteria decision analysis in emergency management. Two DEA-based optimization
models are constructed to facilitate identifying parameter information regarding criterion weights and quantifying qualitative
criteria in TOPSIS. An emergency management case study utilizing data from the Emergency Management Australia (EMA) Disasters
Database is provided to demonstrate the feasibility of the proposed analysis procedure. 相似文献
124.
Jinguang Liu 《系统科学与信息学报》2009,7(4):351-358
Command Decision Simulation (CDS) is not only an important and difficult issue in the field of simulation, but also a technique issue to be tackled in the course of collective Modeling and Simulation in Joint Operations Experiment Center. CDS can give support to all kinds of simulation. Using computer to realize the Blue side's command deci- sion automatic execution in the operation training simulation system can improve training effect. Using computer to realize the lower level command unit's automatic command deci- sion can help to reduce the number of controllers and release them from heavy work. It can also enlarge simulation scale and increase the freedom of the simulation entity especially the command entity, thus enhance the authenticity and credibility of the simulation. Ac- cording to the command decision structure and the Joint Intention Theory, the thesis puts forward the method of making use of Coordination Matrix (CM) to realizing cooperation among the entities in CDS and constructs the calculation sketch of Task Execution, Task Monitoring and Task Replanning. At the same time, the thesis brings forward the CDS structure vision based on Partial Global Planning(PGP). As CM is an indispensable part of combat simulation, the theory and the method of CDS will become an important part for the theory of Combat Simulation. 相似文献
125.
New computing method of weighted coefficients for tracking a maneuvering target using PDAF in the presence of clutter 下载免费PDF全文
To avoid or reduce the influence of unpredictable motion mode on data association, a new computing method of weighted coefficients of measurements for PDAF is presented in which it is assumed that the current turn rate of a maneuvering target changes within a limited range and its turn may be in arbitrary direction during data association. Thus, the predicted center for computing the weighted coefficients is a curved surface in 3-D
space, which differs from the predicted center for setting up a validation gate, namely, a point in 3-D space. The distance between a measurement and the curved surface is used to compute its weighted coefficient. To reduce the computational complexity of weighted coefficients, the formulas for computing the maneuvering direction angle and turn rate corresponding to a measurement are presented. Simulation results show the proposed method reduces the percentage of lost tracks and improves the state estimation accuracy in tracking a maneuvering target using PDAF in the presence of clutter. 相似文献
126.
DDFS spurious signals due to amplitude quantization in absence of phase-accumulator truncation 下载免费PDF全文
Spurious signals in direct digital frequency synthesizers (DDFSs) are partly caused by amplitude quantization and phase truncation, which affect their application to many wireless telecommunication systems. Thee signals are deterministic and periodic in the time domain, so they appear as line spectra in the frequency domain. Two types of spurious signals due to amplitude quantization are exactly formulated and compared in thetime and frequency domains respectively. Then the frequency spectra and power levels of the spurious signals due to amplitude quantization in the absence of phase-accumulator truncation are emphatically analyzed, and the effects of the DDFS parameter variations on the spurious signals are thoroughly studied by computer simulation. And several important conclusions are derived which can provide theoretical support for parameter choice and spurious performance evaluation in the application of DDFSs. 相似文献
127.
The authors propose a V
N, p
test statistic for testing finite-order serial correlation in a semiparametric varying coefficient partially linear errors-in-variables
model. The test statistic is shown to have asymptotic normal distribution under the null hypothesis of no serial correlation.
Some Monte Carlo experiments are conducted to examine the finite sample performance of the proposed V
N, p
test statistic. Simulation results confirm that the proposed test performs satisfactorily in estimated size and power.
This research is supported by the National Natural Science Foundation of China under Grant Nos. 10871217 and 40574003; the
Science and Technology Project of Chongqing Education Committee under Grant No. KJ080609; the Doctor's Start-up Research Fund
under Grant No. 08-52204; and the Youth Science Research Fund of Chongqing Technology and Business University under Grant
No. 0852008. 相似文献
128.
129.
130.
Journal of Systems Science and Complexity - Nonlinear feedback shift registers (NFSRs) are widely used as building blocks in the design of stream ciphers. Let NFSR(f) be an NFSR with the... 相似文献