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Temporal evidence combination method for multi-sensor target recognition based on DS theory and IFS 被引量:4
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作者 Ju Wang Fuxian Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第6期1114-1125,共12页
In order to effectively deal with the conflict temporal evidences without affecting the sequential and dynamic characteristics in the multi-sensor target recognition(MSTR) system at the decision making level, this pap... In order to effectively deal with the conflict temporal evidences without affecting the sequential and dynamic characteristics in the multi-sensor target recognition(MSTR) system at the decision making level, this paper proposes a Dempster-Shafer(DS) theory and intuitionistic fuzzy set(IFS) based temporal evidence combination method(DSIFS-TECM). To realize the method,the relationship between DS theory and IFS is firstly analyzed. And then the intuitionistic fuzzy possibility degree of intuitionistic fuzzy value(IFPD-IFV) is defined, and a novel ranking method with isotonicity for IFV is proposed. Finally, a calculation method for relative reliability factor(RRF) is designed based on the proposed ranking method. As a proof of the method, numerical analysis and experimental simulation are performed. The results indicate DSIFS-TECM is capable of dealing with the conflict temporal evidences and sensitive to the changing of time. Furthermore, compared with the existing methods, DSIFS-TECM has stronger ability of anti-interference. 展开更多
关键词 Dempster-Shafer(DS) theory intuitionistic fuzzy set(IFS) temporal evidence combination relative reliability factor
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Correcting the systematic error of the density functional theory calculation:the alternate combination approach of genetic algorithm and neural network 被引量:1
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作者 王婷婷 李文龙 +1 位作者 陈章辉 缪灵 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期437-444,共8页
The alternate combinational approach of genetic algorithm and neural network (AGANN) has been presented to correct the systematic error of the density functional theory (DFT) calculation. It treats the DFT as a bl... The alternate combinational approach of genetic algorithm and neural network (AGANN) has been presented to correct the systematic error of the density functional theory (DFT) calculation. It treats the DFT as a black box and models the error through external statistical information. As a demonstration, the ACANN method has been applied in the correction of the lattice energies from the DFT calculation for 72 metal halides and hydrides. Through the AGANN correction, the mean absolute value of the relative errors of the calculated lattice energies to the experimental values decreases from 4.93% to 1.20% in the testing set. For comparison, the neural network approach reduces the mean value to 2.56%. And for the common combinational approach of genetic algorithm and neural network, the value drops to 2.15%. The multiple linear regression method almost has no correction effect here. 展开更多
关键词 density functional theory neural network genetic algorithm alternate combination
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Project-based Language Learning: an Activity Theory Analysis in SOE Language Learning
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作者 陈苡晴 《海外英语》 2016年第10期215-217,220,共4页
This study focuses on the effectiveness of the project-based language learning(PBLL) in a college Secretarial Oral English(SOE) Module. Student reflections of the language project work have been analyzed through Activ... This study focuses on the effectiveness of the project-based language learning(PBLL) in a college Secretarial Oral English(SOE) Module. Student reflections of the language project work have been analyzed through Activity Theory. Moreover,Data has been collected and categorized based on the components of complex human activity: the subject, object, tools(signs,symbols, and language), the community in which the activity take place, division of labor, and rules. The findings theoretically support the outcome of project-based language learning which align with the object of the activity. 展开更多
关键词 ACTIVITY theory PROJECT-baseD LEARNING SOE LANGUAGE LEARNING
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Target recognition based on modified combination rule 被引量:16
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作者 Chen Tianlu Que Peiwen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期279-283,共5页
Evidence theory is widely used in the field of target recognition. The invalidation problem of this theory when dealing with highly conflict evidences is a research hotspot. Several alternatives of the combination rul... Evidence theory is widely used in the field of target recognition. The invalidation problem of this theory when dealing with highly conflict evidences is a research hotspot. Several alternatives of the combination rule are analyzed and compared. A new combination approach is proposed. Calculate the reliabilities of evidence sources using existing evidences. Construct reliabilities judge matrixes and get the weights of each evidence source. Weight average all inputted evidences. Combine processed evidences with D-S combination rule repeatedly to identify a target. The application in multi-sensor target reeognition as well as the comparison with typical alternatives all validated that this approach can dispose highly conflict evidences efficiently and get reasonable reeognition results rapidly. 展开更多
关键词 evidence theory combination rule conflict evidences target recognition data fusion.
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Landslides susceptibility mapping in Guizhou province based on fuzzy theory 被引量:8
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作者 WANG Wei-dong XIE Cui-ming DU Xiang-gang 《Mining Science and Technology》 EI CAS 2009年第3期399-404,共6页
The purpose of this study was to assess the susceptibility of landslides around the area of Guizhou province based on fuzzy theory.In first instance, slope, elevation, lithology, proximity to tectonic lines, proximity... The purpose of this study was to assess the susceptibility of landslides around the area of Guizhou province based on fuzzy theory.In first instance, slope, elevation, lithology, proximity to tectonic lines, proximity to drainage and annual precipitation were taken as independent, causal factors in this study.A landslide hazard evaluation factor system was established by classifying these factors into more subclasses according to some rules.Secondly, a trapezoidal fuzzy number weighting(TFNW) approach was used to assess the importance of six causal factors to landslides in an ArcGIS environment.Thirdly, a landslide susceptibility map was created based on a weighted linear combination model.According to this susceptibility map, the study area was classified into four categories of landslide susceptibility:low, moderate, high and very high.Finally, in order to verify the results obtained, the susceptibility map and the landslide inventory map were combined in the GIS.In addition, the weighting procedure showed that TFNW is an efficient method for weighting causal landslide factors. 展开更多
关键词 landslides susceptibility mapping fuzzy theory GIS weighted linear combination
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Theory of mind deficits in patients with esophageal cancer combined with depression 被引量:2
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作者 Yin Cao Quan-Di Zhao +4 位作者 Li-Jun Hu Zhi-Qin Sun Su-Ping Sun Wen-Wei Yun Yong-Gui Yuan 《World Journal of Gastroenterology》 SCIE CAS 2013年第19期2969-2973,共5页
AIM:To characterize the two components of theory of mind(ToM) in patients with esophageal cancer combined with depression.METHODS:Sixty-five patients with esophageal cancer combined with depression(depressed group) an... AIM:To characterize the two components of theory of mind(ToM) in patients with esophageal cancer combined with depression.METHODS:Sixty-five patients with esophageal cancer combined with depression(depressed group) and 62 normal controls(control group) were assessed using reading the mind in the eyes test,faux pas task,verbal fluency test,digit span test and WAIS IQ test.The depressed group was divided into two subgroups including psychotic depressed(PD) group(32 cases) and nonpsychotic depressed(NPD) group(33 cases).The clinical symptoms of patients were assessed using Beck depression inventory version Ⅱ and brief psychiatric reacting scale(BPRS).RESULTS:There was a significant difference between the depressed group and the control group on tasks involving ToM social perceptual components(mind reading:t = 7.39,P < 0.01) and tests involving ToM social cognitive components(faux pas questions:t = 13.75,P < 0.01),respectively.A significant difference was also found among the PD group,the NPD group and the control group on mind reading(F = 32.98,P < 0.01) and faux pas questions(χ 2 = 78.15,P < 0.01),respectively.The PD group and NPD group performed worse than normal group controls both on mind reading and faux pas questions(P < 0.05).The PD group performed significantly worse than the NPD group on tasks involving ToM(mind reading:F = 18.99,P < 0.01;faux pas questions:F = 36.01,P < 0.01).In the depressed group,there was a negative correlation between ToM performances and BPRS total score(mind reading:r =-0.35,P < 0.01;faux pas questions:r =-0.51,P < 0.01),and between ToM performances and hostile suspiciousness factor score(mind reading:r =-0.75,P < 0.01;faux pas questions:r =-0.73,P < 0.01),respectively.CONCLUSION:The two components of ToM are both impaired in patients with esophageal cancer combined with depression.This indicates that there may be an association between ToM deficits and psychotic symptoms in clinical depression. 展开更多
关键词 ESOPHAGEAL cancer combinED with DEPRESSION theory of MIND SOCIAL perceptual COMPONENT SOCIAL cognitive COMPONENT
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New weighting factors assignment of evidence theorybased one vidence distance 被引量:3
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作者 ChenLiangzhou ShiWenkang DuFeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期273-278,共6页
Evidence theory has been widely used in the information fusion for its effectiveness of the uncertainty reasoning. However, the classical DS evidence theory involves counter-intuitive behaviors when the high conflict ... Evidence theory has been widely used in the information fusion for its effectiveness of the uncertainty reasoning. However, the classical DS evidence theory involves counter-intuitive behaviors when the high conflict information exists. Based on the analysis of some modified methods, Assigning the weighting factors according to the intrinsic characteristics of the existing evidence sources is proposed, which is determined on the evidence distance theory. From the numerical examples, the proposed method provides a reasonable result with good convergence efficiency. In addition, the new rule retrieves to the Yager's formula when all the evidence sources contradict to each other completely. 展开更多
关键词 evidence theory rule of combination weighting factors evidence distance.
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Evidence combination method in time domain based on reliability and importance 被引量:2
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作者 LUO Chengkun CHEN Yunxiang +2 位作者 XIANG Huachun WANG Weijia WANG Zezhou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1308-1316,共9页
In order to achieve the information fusion in the time domain based on the evidence theory, an evidence combination method in the time domain based on reliability and importance is proposed according to the idea of ev... In order to achieve the information fusion in the time domain based on the evidence theory, an evidence combination method in the time domain based on reliability and importance is proposed according to the idea of evidence discount. Firstly, the distortion of the time-domain evidence is judged based on single exponential smoothing. The real-time reliability of the evidence at the adjacent time is obtained by the real-time reliability assessment method of the evidence based on the credibility decay model.Then, the relative importance of the evidence at the adjacent time is obtained by comprehensively considering improved conflict degree and uncertainty. Finally, based on the criterion of evidence discount and the Dempster’s rule of combination, the evidence combination is carried out to achieve the sequential combination of time-domain evidence. The numerical simulation and analysis show that this method has fully embodied the dynamic characteristics of time-domain evidence combination, and it has strong processing ability for conflict information and anti-disturbing ability.The proposed method has good applicability to information fusion in the time domain. 展开更多
关键词 evidence theory time-domain evidence combination evidence discount RELIABILITY IMPORTANCE
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Game theory-based attack and defense analysis in virtual wireless networks with jammers and eavesdroppers 被引量:3
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作者 Bassma S.Alsulami Chandra Bajracharya Danda B.Rawat 《Digital Communications and Networks》 SCIE CSCD 2021年第3期327-334,共8页
Dynamic spectrum sharing and cognitive radio networks were proposed to enhance the Radio Frequency(RF)spectrum utilization.However,there are several challenges to realize them in real systems,such as sensing uncertain... Dynamic spectrum sharing and cognitive radio networks were proposed to enhance the Radio Frequency(RF)spectrum utilization.However,there are several challenges to realize them in real systems,such as sensing uncertainty causing issues to licensed users,business models for licensed service providers.Wireless virtualization is regarded as a technology that leverages service level agreements to sublease unused or underutilized RF spectrum that addresses aforementioned issues and helps to significantly enhance the utilization of the RF spectrum,offer improved coverage and capacity of networks,enhance network security and reduce energy consumption.With wireless virtualization,wireless networks'physical substrate is shared and reconfigured dynamically between virtual wireless networks through Mobile Virtual Network Operations(MVNOs).Wireless virtualization with dynamic configurable features of Wireless Infrastructure Providers(WIPs),virtualized wireless networks are vulnerable to a multitude of attacks,including jamming attacks and eavesdropping attacks.This paper investigates a means of defense through the employment of coalition game theory when jammers try to degrade the signal quality of legitimate users,and eavesdroppers aim to reduce secrecy rates.Specifically,we consider a virtual wireless network where MVNO users'job is to improve their Signal to Interference plus Noise Ratio(SINR)while the jammers target to collectively enhance their Jammer Received Signal Strength(JRSS),and an eavesdropper's goal is to reduce the overall secrecy rate.Numerical results have demonstrated that the proposed game strategies are effective(in terms of data rate,secrecy rate and latency)against such attackers compared to the traditional approaches. 展开更多
关键词 Game theory based security Virtual wireless networks Jamming and eavesdropping
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Wavelet Bases Made of Piecewise Polynomial Functions: Theory and Applications 被引量:1
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作者 Lorella Fatone Maria Cristina Recchioni Francesco Zirilli 《Applied Mathematics》 2011年第2期196-216,共21页
We present wavelet bases made of piecewise (low degree) polynomial functions with an (arbitrary) assigned number of vanishing moments. We study some of the properties of these wavelet bases;in particular we consider t... We present wavelet bases made of piecewise (low degree) polynomial functions with an (arbitrary) assigned number of vanishing moments. We study some of the properties of these wavelet bases;in particular we consider their use in the approximation of functions and in numerical quadrature. We focus on two applications: integral kernel sparsification and digital image compression and reconstruction. In these application areas the use of these wavelet bases gives very satisfactory results. 展开更多
关键词 APPROXIMATION theory WAVELET baseS KERNEL Sparsification Image Compression
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Thermal Analysis of Organic Light Emitting Diodes Based on Basic Heat Transfer Theory 被引量:1
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作者 张稳稳 吴朝新 +3 位作者 刘迎文 董军 严学文 侯洵 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期139-143,共5页
We investigate the thermal characteristics of standard organic light-emitting diodes (OLEDs) using a simple and clear 1D thermal model based on the basic heat transfer theory. The thermal model can accurately estima... We investigate the thermal characteristics of standard organic light-emitting diodes (OLEDs) using a simple and clear 1D thermal model based on the basic heat transfer theory. The thermal model can accurately estimate the device temperature, which is linearly with electrical input power. The simulation results show that there is almost no temperature gradient within the OLED device working under steady state conditions. Furthermore, thermal analysis simulation results show that the surface properties (convective heat transfer coetficient and surface emissivity) of the substrate or cathode can significantly affect the temperature distribution of the OLED. 展开更多
关键词 OLEDS Thermal Analysis of Organic Light Emitting Diodes based on Basic Heat Transfer theory EML
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Density Functional Theory Study on La Complex with Schiff-base as Building Block 被引量:6
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作者 XIA Shu-Wei XU Xiang SUN Ya-Li FAN Yu-Hua BI Cai-Feng ZHANG Dong-Mei YANG Li-Rong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期197-203,共7页
Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized an... Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized and the calculation results show that the lanthanum ion is coordinated by one nitrogen atom and three oxygen atoms of L^1 and two oxygen atoms of nitrate ion. The bond length of La-N is 0.2637 nm and the average length of La-O is 0.2526 nm, which are consistent with the literatures. In addition, the stabilities, electronic structural characteristics and IR spectra of the complex have been analyzed, which describe the coordination of lanthanum ion with other atoms in detail. 展开更多
关键词 RARE-EARTH SCHIFF-base lanthanum complex density functional theory
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Application of periodic orbit theory in chaos-based security analysis 被引量:3
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作者 龙敏 丘水生 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2254-2258,共5页
Chaos-based encryption schemes have been studied extensively, while the security analysis methods for them are still problems to be resolved. Based on the periodic orbit theory, this paper proposes a novel security an... Chaos-based encryption schemes have been studied extensively, while the security analysis methods for them are still problems to be resolved. Based on the periodic orbit theory, this paper proposes a novel security analysis method. The periodic orbits theory indicates that the fundamental frequency of the spiraling orbits is the natural frequency of associated linearized system, which is decided by the parameters of the chaotic system. Thus, it is possible to recover the plaintext of secure communication systems based on chaotic shift keying by getting the average time on the spiraling orbits. Analysis and simulation results show that the security analysis method can break chaos shift keying secure communication systems, which use the parameters as keys. 展开更多
关键词 periodic orbit theory secure communication chaos-based security analysis
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The Source of Groundwater Recharge Based on Entropy Theory in the Arid Areas of North China 被引量:1
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作者 CHEN Jiansheng XU Yi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期390-391,共2页
Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge a... Objective Any natural system is constantly exchanging material, energy and information with the environment, and all tkese processes follow the basic law of thermodynamics, with no exception of groundwater recharge and discharge process. On the basis of the principle of the first law of thermodynamics, the reverse geochemical simulation method is widely used in the study of groundwater recharge, runoff and drainage process. However, some studies only consider the material conservation in theprocess, but ignore the probability of the transformation. 展开更多
关键词 The Source of Groundwater Recharge based on Entropy theory in the Arid Areas of North China
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Theory- and Evidence- Based Intervention: Practice-Based Evidence Integrating Positive Psychology Into a Clinical Psychological Assessment and Intervention Model and How to Measure Outcome 被引量:1
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作者 Poul Nissen 《Psychology Research》 2011年第2期91-105,共15页
关键词 评估模型 干预模式 基础 证据 心理学 干预措施 测量 临床
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An Evidence Combination Method based on DBSCAN Clustering
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作者 Kehua Yang Tian Tan Wei Zhang 《Computers, Materials & Continua》 SCIE EI 2018年第11期269-281,共13页
Dempster-Shafer(D-S)evidence theory is a key technology for integrating uncertain information from multiple sources.However,the combination rules can be paradoxical when the evidence seriously conflict with each other... Dempster-Shafer(D-S)evidence theory is a key technology for integrating uncertain information from multiple sources.However,the combination rules can be paradoxical when the evidence seriously conflict with each other.In the paper,we propose a novel combination algorithm based on unsupervised Density-Based Spatial Clustering of Applications with Noise(DBSCAN)density clustering.In the proposed mechanism,firstly,the original evidence sets are preprocessed by DBSCAN density clustering,and a successfully focal element similarity criteria is used to mine the potential information between the evidence,and make a correct measure of the conflict evidence.Then,two different discount factors are adopted to revise the original evidence sets,based on the result of DBSCAN density clustering.Finally,we conduct the information fusion for the revised evidence sets by D-S combination rules.Simulation results show that the proposed method can effectively solve the synthesis problem of high-conflict evidence,with better accuracy,stability and convergence speed. 展开更多
关键词 D-S evidence theory information fusion DBSCAN combination rules
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Modification of evidence theory based on feature extraction
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作者 杜峰 施文康 邓勇 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第6期667-673,共7页
Although evidence theory has been widely used in information fusion due to its effectiveness of uncertainty reasoning, the classical DS evidence theory involves counter-intuitive behaviors when high conflict informati... Although evidence theory has been widely used in information fusion due to its effectiveness of uncertainty reasoning, the classical DS evidence theory involves counter-intuitive behaviors when high conflict information exists. Many modification methods have been developed which can be classified into the following two kinds of ideas, either modifying the combination rules or modifying the evidence sources. In order to make the modification more reasonable and more effective, this paper gives a thorough analysis of some typical existing modification methods firstly, and then extracts the intrinsic feature of the evidence sources by using evidence distance theory. Based on the extracted features, two modified plans of evidence theory according to the corresponding modification ideas have been proposed. The results of numerical examples prove the good performance of the plans when combining evidence sources with high conflict information. 展开更多
关键词 evidence theory combination rule feature extraction evidence distance
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Adaptive Smoothing Method Based on Fuzzy Theory Study and Realization
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作者 Yao Wan Changlin Hu 《Journal of Computer and Communications》 2015年第5期38-43,共6页
In this paper, we study about a method to optimize the fused track quality in intelligence network of radar target fusion system, considering the role of people in the fusion system;we start to find ways to optimize t... In this paper, we study about a method to optimize the fused track quality in intelligence network of radar target fusion system, considering the role of people in the fusion system;we start to find ways to optimize the quality of the fused track, and adaptive smoothing method is proposed based on fuzzy theory. Tests show that this method can greatly improve the quality of the fused track system for battlefield reconnaissance provides high-quality, high-reliability battlefield. 展开更多
关键词 ADAPTIVE SMOOTHING Method based on FUZZY theory STUDY and REALIZATION
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Correspondence Between Bell Bases and Oriented Links in Knot Theory
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作者 QIANShang-Wu GUZhi-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第6期659-662,共4页
From the comparison of correlation tensor in the theory of quantum network, the Alexander relation matrix in the theory of knot crystals and the identical inversion relations under the action of Pauli matrices, we sho... From the comparison of correlation tensor in the theory of quantum network, the Alexander relation matrix in the theory of knot crystals and the identical inversion relations under the action of Pauli matrices, we show that there is a one to one correspondence between four Bell bases and four oriented links of the linkage in knot theory. 展开更多
关键词 Bell bases correlation tensor in the theory of quantum network Alexander relation matrix in the theory of knot crystals linkage 4(1) inversion relations under the action of Pauli matrices
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A Closure for Isotropic Turbulence Based on Extended Scale Similarity Theory in Physical Space
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作者 Chu-Han Wang Le Fang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第8期5-8,共4页
The closure of a turbulence field is a longstanding fundamental problem, while most closure models are introduced in spectral space. Inspired by Chou's quasi-normal closure method in spectral space, we propose an ana... The closure of a turbulence field is a longstanding fundamental problem, while most closure models are introduced in spectral space. Inspired by Chou's quasi-normal closure method in spectral space, we propose an analytical closure model for isotropic turbulence based on the extended scale similarity theory of the velocity structure function in physical space. The assumptions and certain approximations are justified with direct numerical simulation. The asymptotic scaling properties are reproduced by this new closure method, in comparison to the classical Batchelor model. 展开更多
关键词 DNS A Closure for Isotropic Turbulence based on Extended Scale Similarity theory in Physical Space
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