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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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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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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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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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Preliminary Theoretical Studies on the Combination of Halogen Ions with Crown Tetraalanylpeptide 被引量:3
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作者 Hongtao Song Guoping Liu Yuqing Yang Hui Gao Hongyuan Wei Shunzhong Luo 《Journal of Chemistry and Chemical Engineering》 2010年第4期7-12,共6页
The density functional theory based hybrid-method B3LYP was used to investigate the interaction of the halogen ions with crown tetraalanylpeptide which was the coronary structures of homodetic cyclotetraalapeptide and... The density functional theory based hybrid-method B3LYP was used to investigate the interaction of the halogen ions with crown tetraalanylpeptide which was the coronary structures of homodetic cyclotetraalapeptide and was represented as the model basic. Many properties including combination energy, optimum geometry structures and population analysis were calculated. It was shown that there was scarcely any change in the coronary structure of C4-Ala after combination with X. The electrons moved from halogen ions to C4-Ala during the combining process. Combination of C4-Ala with F was obviously stronger than that of Cl^- and Br. When the energy of C4-Ala-X was at minimum, the distances between halogen ions and the center of C4-Ala were 0.084 nm, 0.210 nm and 0.200 nm, respectively. 展开更多
关键词 Density functional theory combination halogen ion crown tetraalanylpeptide.
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Time Evolution Caused by Hamiltonian Composed of Quadratic Combination of Canonical Operators and Time-Dependent Two-Mode Fresnel Operator 被引量:1
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作者 FAN Hong-Yi Hai-Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期599-602,共4页
We show that the time-dependent two-mode Fresnel operator is just the time-evolutional unitary operator governed by the Hamiltonian composed of quadratic combination of canonical operators in the way of exhibiting SU... We show that the time-dependent two-mode Fresnel operator is just the time-evolutional unitary operator governed by the Hamiltonian composed of quadratic combination of canonical operators in the way of exhibiting SU(1,1) algebra. This is an approach for obtaining the time-dependent Hamiltonian from the preassigned time evolution in classical phase space, an approach which is in contrast to Lewis-Riesenfeld's invariant operator theory of treating timedependent harmonic oscillators. 展开更多
关键词 time-dependent two-mode Fresnel operator quadratic combination of canonical operators Lewis-Riesenfeld's invariant operator theory
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Interactive-Adaptive Combination Rule
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作者 金宏斌 蓝江桥 李鸿飞 《China Communications》 SCIE CSCD 2011年第2期140-146,共7页
Aiming at the invalidation of DS theory dealing with the evidence in a high conflict and reducing confidence level of DSm theory processing a low conflict,this paper proposes an interactive-adaptive combination rule. ... Aiming at the invalidation of DS theory dealing with the evidence in a high conflict and reducing confidence level of DSm theory processing a low conflict,this paper proposes an interactive-adaptive combination rule. Adopting the angle similarity based on hyper-power set as the weight of generalized Dempster rule and PCR rule,the new rule adaptively processes various evidence combination issues. In this way,the rule can obtain not only the better fusion of decision making effect in a low conflict,but also the solution to the synthesis in a high conflict. Simulation analysis demonstrates the validity and applicability from this rule of combination. 展开更多
关键词 dezert-smarandache theory dempster-shafer theory interactive-adaptive combination rule conflict evidence
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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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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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Optimization of combined endoreversible Carnot heat engines with different objectives 被引量:4
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作者 程雪涛 梁新刚 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期239-244,共6页
Taking the output power, thermal efficiency, and thermo-economic performance as the optimization objectives, we optimize the operation parameters of a thermodynamic system with combined endoreversible Carnot heat engi... Taking the output power, thermal efficiency, and thermo-economic performance as the optimization objectives, we optimize the operation parameters of a thermodynamic system with combined endoreversible Carnot heat engines in this paper. The applicabilities of the entropy generation minimization and entransy theory to the optimizations are discussed. For the discussed cases, only the entransy loss coefficient is always agreeable to the optimization of thermal efficiency. The applicabilities of the other discussed concepts to the optimizations are conditional. Different concepts and principles are needed for different optimization objectives, and the optimization principles have their application preconditions. When the preconditions are not satisfied, the principles may be not applicable. 展开更多
关键词 combined endoreversible Carnot heat engines entransy theory entropy generation minimization finite time thermodynamics
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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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Reasonable location parameters of pick and nozzle in combined cutting system 被引量:4
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作者 曾锐 杜长龙 +1 位作者 陈荣俊 王文娟 《Journal of Central South University》 SCIE EI CAS 2014年第3期1067-1076,共10页
The drum shearer and high pressure water jet combined cutting system is an effective technology to cut hard coal-rock, but one problem of the technology is the choice of pick and nozzle location parameters. In order t... The drum shearer and high pressure water jet combined cutting system is an effective technology to cut hard coal-rock, but one problem of the technology is the choice of pick and nozzle location parameters. In order to solve the problem, the process and mechanism of combined cutting arc studied and mining seepage catastrophe theory is used to construct the mathematic and physical model of combined cutting hard coal-rock. Based on the model and detailed analysis of combined cutting mechanism, the single pick and nozzle combined cutting test-bed is built to test the main pick and nozzle location parameters of drum shearer and water jet combined cutting system. Test results show that the best vertical distance between the pick-tip and nozzle center point is the sum of cutting thickness and proper target distance in the Y axial direction; the best horizontal distance is the length between pick-tip point and coal-rock surface bursting crack point in the X axial direction. The best incident angle of water jet should be the same as the bursting crack line's angle in theory, but considering other important factors comprehensively, it is more reasonable when the incident angle of water jet is 90°. 展开更多
关键词 combined cutting location parameter water jet mining seepage theory hard coal-rock
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Insights into electrochemical nitrogen reduction reaction mechanisms:Combined effect of single transition-metal and boron atom 被引量:5
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作者 Xingzhu Chen Wee-Jun Ong +2 位作者 Xiujian Zhao Peng Zhang Neng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期577-585,共9页
Developing single-atom catalysts(SACs) for electrochemical devices is a frontier in energy conversion.The comparison of stability,activity and selectivity between various single atoms is one of the main research focus... Developing single-atom catalysts(SACs) for electrochemical devices is a frontier in energy conversion.The comparison of stability,activity and selectivity between various single atoms is one of the main research focuses in SACs.However,the in-depth understanding of the role that the coordination atoms of single atom play in the catalytic process is lacking.Herein,we proposed a graphene-like boroncarbon-nitride(BCN) monolayer as the support of single metal atom.The electrocatalytic nitrogen reduction reaction(eNRR) performances of 3 d,4 d transition metal(TM) atoms embedded in defective BCN were systematically investigated by means of density functional theory(DFT) computations.Our study shows that the TM-to-N and B-to-N π-back bonding can contribute to the activation of N_(2).Importantly,a combined effect is revealed between single TM atom and boron atom on eNRR:TM atom enhances the nitrogen reduction process especially in facilitating the N_(2) adsorption and the NH3 desorption,while boron atom modulates the bonding strength of key intermediates by balancing the charged species.Furthermore,Nb@BN3 possesses the highest electrocata lytic activity with limiting potential of-0.49 V,and exhibits a high selectivity for nitrogen reduction reaction(NRR) to ammonia compared with hydrogen evolution reaction(HER).As such,this work can stimulate a research doorway for designing multi-active sites of the anchored single atoms and the innate atoms of substrate based on the mechanistic insights to guide future eNRR research. 展开更多
关键词 Boron-carbon–nitrogen(BCN) Single-atom catalysts Electrocatalytic nitrogen reduction reaction Density functional theory combined effect
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Analytic elasticity solution of bi-modulus beams under combined loads 被引量:1
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作者 Huiling ZHAO Zhiming YE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第4期427-438,共12页
A unified stress function for bi-modulus beams is proposed based on its mechanic sense on the boundary of beams. Elasticity solutions of stress and displacement for bi-modulus beams under combined loads are derived. T... A unified stress function for bi-modulus beams is proposed based on its mechanic sense on the boundary of beams. Elasticity solutions of stress and displacement for bi-modulus beams under combined loads are derived. The example analysis shows that the maximum tensile stress using the same elastic modulus theory is underestimated if the tensile elastic modulus is larger than the compressive elastic modulus. Otherwise, the maximum compressive stress is underestimated. The maximum tensile stress using the material mechanics solution is underestimated when the tensile elastic modulus is larger than the compressive elastic modulus to a certain extent. The error of stress using the material mechanics theory decreases as the span-to-height ratio of beams increases, which is apparent when L/h ≤ 5. The error also varies with the distributed load patterns. 展开更多
关键词 bi-modulus elasticity theory analytic solution combined loads
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Buckling analysis of shear deformable composite conical shells reinforced by CNTs subjected to combined loading on the two-parameter elastic foundation 被引量:3
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作者 A.H.Sofiyev N.Kuruoglu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第2期205-218,共14页
The main objective of this study is to investigate the buckling analysis of CCSs reinforced by CNTs subjected to combined loading of hydrostatic pressure and axial compression resting on the twoparameter elastic found... The main objective of this study is to investigate the buckling analysis of CCSs reinforced by CNTs subjected to combined loading of hydrostatic pressure and axial compression resting on the twoparameter elastic foundation(T-P-EF).It is one of the first attempts to derive the governing equations of the CCSs reinforced with CNTs,based on a generalized first-order shear deformation shell theory(FSDST)which includes shell-foundation interaction.By adopting the extended mixing rule,the effective material properties of CCSs reinforced by CNTs with linear distributions are approximated by introducing some efficiency parameters.Three carbon nanotube distribution in the matrix,i.e.uniform distribution(U)and V and X-types linear distribution are taken into account.The stability equations are solved by using the Galerkin procedure to determine the combined buckling loads(CBLs)of the structure selected here.The numerical illustrations cover CBLs characteristics of CCSs reinforced by CNTs in the presence of the T-P-EF.Finally,a parametric study is carried out to study the influences of the foundation parameters,the volume fraction of carbon nanotubes and the types of reinforcement on the CBLs. 展开更多
关键词 NANOCOMPOSITES CNTS Composite conical shells Two-parameter elastic foundations combined buckling loads Shear deformation shell theories
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Postbuckling of Imperfect Stiffened Cylindrical Shells Under Combined External Liquid Pressure and Axial Compression 被引量:1
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作者 Shen HuishenProfessor, Department of Civil Engineering. Shanghai Jiao Tong University. Shanghai 200030 《China Ocean Engineering》 SCIE EI 1996年第4期367-390,共24页
posthuckling analysis is presented for the stilTened cylindrical shell of finite length subjected to combined loading of external liquid pressure and axial compression. The formulations are based on a boundary layer t... posthuckling analysis is presented for the stilTened cylindrical shell of finite length subjected to combined loading of external liquid pressure and axial compression. The formulations are based on a boundary layer theory of shell buckling, which includes the effects of nonlinear prebuckling deformations, nonlinear large deflections in the postbuckling range and initial geometrical imperfections of the shell. The 'smeared stifl'cner' approach is adopted for the stiffencrs. In the analysis a singular perturbation technique is used (o determine the interactive buckling loads and the postbuckling paths. Numerical examples cover the performance of perfect and imperfect, stringer and ring stiffened cylindrical shells. Typical results arc presented in the dimcnsionless graphical form. 展开更多
关键词 structural stability ptwtbuckling stiffened cylindrical shell combined loading boundary layer theory of shell buckling singular perturbation technique.
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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock 被引量:2
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作者 Tienan Wang Yue Zhai +2 位作者 Huan Gao Yubai Li Ruifeng Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期601-616,共16页
Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ... Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering. 展开更多
关键词 combined body stress-strain relationship Hooke’s law Effective medium theory Stress threshold determination
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STUDY OF GYROMONOTRON WITH A COMBINING PERIODIC MAGNETIC FIELD AND A COAXIAL CYCLOTRON ELECTRON BEAM
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作者 吴坚强 《Journal of Electronics(China)》 1989年第2期129-139,共11页
On the basis of a work of Wu Jianqiang et al.(1987),by making use of the linear kinetictheory,the gyromonotron with a combining periodic magnetic field and a coaxial cyclotron electron beam hasbeen analysed in detail.... On the basis of a work of Wu Jianqiang et al.(1987),by making use of the linear kinetictheory,the gyromonotron with a combining periodic magnetic field and a coaxial cyclotron electron beam hasbeen analysed in detail.And the formulas of the electron beam to wave interaction power,frequency shift andstarting current,etc.have been derived. 展开更多
关键词 Linear KINETIC theory Gyromonotron combinING PERIODIC magnetic filed COAXIAL CYCLOTRON electron beam
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POSTBUCKLING OF IMPERFECT STIFFENED CYLINDRICAL SHELLS UNDER COMBINED EXTERNAL PRESSURE AND HEATING
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作者 沈惠申 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第5期411-423,共16页
A postbuckling analysis is presented for a stiffened cylindrical shell of finite length subjected to combined loading of external pressure and a uniform temperature rise. The formulations are based on a boundary layer... A postbuckling analysis is presented for a stiffened cylindrical shell of finite length subjected to combined loading of external pressure and a uniform temperature rise. The formulations are based on a boundary layer theory of shell buckling, which includes the effects of nonlinear prebuckling deformations, nonlinear large deflections in the postbuckling range and initial geometrical imperfections of the shell. The 'smeared stiffener' approach is adopted for the stiffeners. The analysis uses a singular perturbation technique to determine the interactive buckling loads and the postbuckling equilibrium paths. Numerical examples cover the performances of perfect and imperfect, stringer and ring stiffened cylindrical shells. Typical results are presented in dimensionless graphical form. 展开更多
关键词 POSTBUCKLING thermal postbuckling stiffened cylindrical shell combined loading a boundary layer theory of shell buckling singular perturbation technique
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