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Linear QSAR Regression Models for the Prediction of Bioconcentration Factors of Chloroanilines in Fish by Density Functional Theory 被引量:16
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作者 冯长君 杨伟华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期830-834,共5页
Density functional theory(DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationshi... Density functional theory(DFT)-B3LYP level with the 6-311G**(d,p) basis set was used to calculate a set of molecular quantum chemical descriptors of 12 chloroanilines. Quantitative structure-activity relationship(QSAR) models of the bioconcentration factors(BCF) of the anilines in fish were established using some of the following calculated descriptors: EHOMO, ENHOMO, ELUMO, ENLUMO, ΔE1(= ELUMO- EHOMO), ΔE2(= ENLUMO- ENHOMO), dipole moment(μ), molecular volume(V), vibrational energy of 0 K(Ev), thermodynamic energy(E), heat capacity(Cv), entropy(Sm) and the charge of benzene ring(Qph). Using the variable selection and leaps-and-bounds regression, the quantum chemical descriptors derived directly from the molecular structures were employed to develop a linear QSAR model between the bioconcentration factors(BCF) and two descriptors(Sm, ENHOMO) of 12 chloroanilines. Statistically, the most significant one is a two-parameter linear equation with the correlation coefficient(R^2) of 0.981 and cross-validated correlation coefficient(Rcv^2) of 0.967. The established QSAR model has good stability and predictability based on the results from Rcv2 of leave-one-out cross-validation, AIC, FIT and tα/2. The quantum chemical analyses were performed from two aspects of frontier molecular orbital and entropy. The results show that two structural describers are crucial to the bioconcentration activity of chloroanilines. 展开更多
关键词 CHLOROANILINES bioconcentration factor density functional theory quantum chemical describers quantitative structure-activity relationship
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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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Application of the Third Theory of Quantification in Screening Sensitive Geological Factors Influencing Coal and Gas Outburst 被引量:2
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作者 吴财芳 曾勇 张许良 《Journal of China University of Mining and Technology》 2003年第1期66-71,共6页
The principles of the third theory of quantification were discussed. The concept and calculation method of reaction degree were put forward, which have extended the applying range and scientificalness of the primary r... The principles of the third theory of quantification were discussed. The concept and calculation method of reaction degree were put forward, which have extended the applying range and scientificalness of the primary reaction. Taking the Zhongmacun mine as an example, the geological factors affecting coal and gas outburst were researched. Eight sensitive factors for the outburst of coal and gas were screened out from 11 geological factors using the method of unit classification and the third theory of quantification. On the basis of this, the Zhongmacun coal mine was classified into several divisions. The practice shows that it is feasible to apply the third theory of quantification to gas geology, which offers a new thought to screen the sensitive geological factors of gas outburst forecast. 展开更多
关键词 the third theory of quantification reaction degree sensitive geological factor gas outburst forecast
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Impact of meteorological factors on the incidence of influenza in Beijing: A 35-year retrospective study based on Yunqi theory 被引量:2
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作者 Hong Wang Xuan Zhang +5 位作者 Zhili Gao Ling Han Zhongdi Liu Long Yan Mingyue Li Juan He 《Journal of Traditional Chinese Medical Sciences》 2018年第3期264-270,共7页
Objective:To analyze the impact of meteorological factors on the incidence of influenza based on the Yunqi theory in Beijing area,and to establish an effective forecast modelMethods:Monthly data on the incidence of in... Objective:To analyze the impact of meteorological factors on the incidence of influenza based on the Yunqi theory in Beijing area,and to establish an effective forecast modelMethods:Monthly data on the incidence of influenza from 1970 to 2004 and daily data on the meteorological factors (including daily averages of temperature,wind speed,relative humidity,vapor pressure,and daily total precipitation) from 1966 to 2004 were collected and processed under the traditional Chinese medicine (TCM) theory of six qi.A back-propagation artificial neural network was then performed to analyze the data.Results:The highest incidence of influenza occurs in the sixth qi (the period of December and January),which is characterized by dryness and coldness.Altogether six models were successfully established.Climatic data used were of the same year,one year prior,two years prior,and three years prior to the influenza data respectively.The last two models involve climatic data of the previous three years plus the current year and of the past four years plus the current year.Finally,we determined the fifth model has the highest forecast accuracy (49%).Conclusions:Meteorological factors can exert an influence on the incidence of influenza,which corresponds to TCM theory that 'the pestilence occurred three years after the abnormal climatic changes'.This study may generate interest among the public health community and other TCM theories can be applied so that public health measures can be taken to prevent and control influenza,particularly during the winter months. 展开更多
关键词 INCIDENCE of INFLUENZA METEOROLOGICAL factors Yunqi theory BACK-PROPAGATION artificial NEURAL network
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An Empirical Examination of the Arbitrage Pricing Theory:Evidences from the U.S.Stock Market
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作者 Mahdy F.Elhusseiny Nyakundi M.Michieka Benjamin Bae 《Journal of Modern Accounting and Auditing》 2019年第2期69-79,共11页
This study investigates the effects of changes in local macroeconomic risk factors on returns on the banking,chemicals,insurance,telecommunication,and utilities industries in the U.S.market.Using a multifactor pricing... This study investigates the effects of changes in local macroeconomic risk factors on returns on the banking,chemicals,insurance,telecommunication,and utilities industries in the U.S.market.Using a multifactor pricing model and data from 1998:01 to 2017:12,empirical results show that the banking,chemical,and telecommunication industries show more differences in their stock reactions to local macroeconomic risk factors.The insurance and telecommunication industries do not react significantly to risk factors.However,all the industries show strong reactions to local market portfolio. 展开更多
关键词 ARBITRAGE PRICING theory MACROECONOMIC factors multifactor PRICING model
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Overview and Graph Theory of the Immune System of Crustacean 被引量:1
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作者 马寨璞 张繁霜 井爱芹 《Agricultural Science & Technology》 CAS 2010年第8期19-23,38,共6页
In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and ef... In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and effects of these factors,different symbolic forms are introduced to express the effects,and ultimately the whole node graph of the system is obtained. The graph theory can be used for further researches on the immune system of crustacean. 展开更多
关键词 CRUSTACEAN Immune system Immune factors Graph theory
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A Study of New Consumption from the Perspective of Mediatization:Essence, Contributing Factors, and Reinvention of Rules
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作者 Chen Shi 《Contemporary Social Sciences》 2022年第4期39-57,共19页
Most of the existing literature on the emergence of new consumption and its essence is based on the discussion of micro consumption phenomena. This paper takes new consumption phenomena in the digital media-dominated ... Most of the existing literature on the emergence of new consumption and its essence is based on the discussion of micro consumption phenomena. This paper takes new consumption phenomena in the digital media-dominated polymedia environment as the object of study to review the theoretical history of “mediatization,” and explores new consumption’s emergence, essence, and related issues systematically through deductive reasoning. More specifically, this paper is to first interpret the mediatization theory and then analyze two dimensions(i.e., the formation of mediatized consumption and the resultant reinvention of practice rules) from the perspective of media affordances. On this basis, we conclude mediatized consumption’s essence, forms, and practice rules. This study indicates that new consumption is essentially mediatized consumption, which concerns “media-shaped consumption” and “consumption-shaped media,” and that new consumption has two representations;consumption-oriented media and banal consumption. Media affordances make new consumption fields human-oriented, connecting “people” and “things,” and are becoming a major contributor to the formation of mediatized consumption. Thus, the practice rules concerning “people, goods, and fields” in the new consumption sector are reinvented;the social interactions in the “middle region” are highlighted;the imaginative, narrative, and social characteristics of goods are emphasized;and the cross-field integration of consumption is realized. 展开更多
关键词 new consumption mediatization theory ESSENCE contributing factors practice rules
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The core ideology of Ecological Marxism:Marx is the pioneer of internal factors theory of ecological environment
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作者 Liu Sihua 《Ecological Economy》 2007年第4期346-354,共9页
This paper from the unified visual angle of philosophy and economics has observed Marx's theory of ecological economics, clarified the misunderstanding on Marx's theory of nature and ecological environmental t... This paper from the unified visual angle of philosophy and economics has observed Marx's theory of ecological economics, clarified the misunderstanding on Marx's theory of nature and ecological environmental thought at home and abroad for a long time, studied systematically and deeply the Marx's thought that natural and ecological environment is external condition and internal elements of human social economic growth, confirmed firstly Marx is the forerunner who established the theory of internal cause of natural ecological environment. It is of far-reaching academic and practical significance. 展开更多
关键词 Marx Natural environment Ecological economics theory of internal factors
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On Dynamic Social Factors for Development of China’s Human Rights Theory
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作者 FAN JIZENG 《The Journal of Human Rights》 2011年第4期20-22,共3页
China's mainstream human rights theory has undergone tremendous changes since the reform-and-opening scheme was kicked off in the early 1980s. "Human rights," which used to be seen as a concept of capitalist ideolo... China's mainstream human rights theory has undergone tremendous changes since the reform-and-opening scheme was kicked off in the early 1980s. "Human rights," which used to be seen as a concept of capitalist ideology, is now an important part of the Chinese system of socialist values. 展开更多
关键词 On Dynamic Social factors for Development of China s Human Rights theory
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Effect of Exchange-Correlation Functional on the Structural, Mechanical, and Optoelectronic Properties of Orthorhombic RbSrBr3 Perovskite
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作者 Fatema Najrin Rabeya Bakar Sarna +3 位作者 Md. Alamin Sarker Budrun Neher Md. Mahbubur Rahman Bhuiyan Farid Ahmed 《Materials Sciences and Applications》 2024年第6期137-154,共18页
In the present study, the effect of the exchange-correlation functional on the structural, mechanical, and optoelectronic properties of orthorhombic RbSrBr3 perovskite has been investigated using various functionals i... In the present study, the effect of the exchange-correlation functional on the structural, mechanical, and optoelectronic properties of orthorhombic RbSrBr3 perovskite has been investigated using various functionals in Density Functional Theory (DFT) with the CASTEP code. The optimized lattice parameters are quite similar for all the functionals. The electronic properties have shown that RbSrBr3 perovskite is a wide direct band gap compound with a band gap energy ranging from 4.296 eV to 4.494 eV for all the functionals. The mechanical parameters like elastic constants, Young’s modulus, Shear modulus, Poisson’s ratio, Pugh’s ratio, and an anisotropic factor reveal that the RbSrBr3 perovskite has ductile behavior and an anisotropic nature which signifies the mechanical stability of the compound. The Debye temperature might withstand lattice vibration heat. High absorption coefficient (>104 cm−1), high optical conductivity, and very low reflectivity have been found in the RbSrBr3 perovskite for all functions. The computed findings on the RbSrBr3 perovskite suggested that the presented studied material is potentially applicable for photodetector and optoelectronic devices. 展开更多
关键词 Density Functional theory Mechanical Properties PHOTODETECTOR DUCTILITY Anisotropic Factor
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Period-doubling bifurcation in two-stage power factor correction converters using the method of incremental harmonic balance and Floquet theory 被引量:4
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作者 Wang Fa-Qiang Zhang Hao Ma Xi-Kui 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期153-162,共10页
In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correcti... In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correction converter typically employs a cascade configuration of a pre-regulator boost power factor correction converter with average current mode control to achieve a near unity power factor and a tightly regulated post-regulator DC-DC Buck converter with voltage feedback control to regulate the output voltage. Based on the assumption that the tightly regulated postregulator DC-DC Buck converter is represented as a constant power sink and some other assumptions, the simplified model of the two-stage power factor correction converter is derived and its approximate periodic solution is calculated by the method of IHB. And then, the stability of the system is investigated by using Floquet theory and the stable boundaries are presented on the selected parameter spaces. Finally, some experimental results are given to confirm the effectiveness of the theoretical analysis. 展开更多
关键词 two-stage power factor correction converter incremental harmonic balance Floquet theory period-doubling bifurcation
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Fluid–solid coupling analysis of rock pillar stability for concealed karst cave ahead of a roadway based on catastrophic theory 被引量:10
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作者 Zhao Yanlin Peng Qingyang +2 位作者 Wan Wen Wang Weijun Chen Bin 《International Journal of Mining Science and Technology》 SCIE EI 2014年第6期737-745,共9页
In order to study the mechanism of water inrush from a concealed, confined karst cave, we established a fluid–solid coupling model of water inrush from a concealed karst cave ahead of a roadway and a strength reducti... In order to study the mechanism of water inrush from a concealed, confined karst cave, we established a fluid–solid coupling model of water inrush from a concealed karst cave ahead of a roadway and a strength reduction method in a rock pillar for preventing water inrush based on catastrophic theory. Fluid–solid coupling effects and safety margins in a rock pillar were studied. Analysis shows that rock pillar instability, exerted by disturbance stress and seepage stress, is the process of rock pillar catastrophic destabilization induced by nonlinear extension of plastic zones in the rock pillar. Seepage flow emerges in the rock pillar for preventing water inrush, accompanied by mechanical instability of the rock pillar. Taking the accident of a confined karst cave water-inrush of Qiyi Mine as an example, by studying the safety factor of the rock pillar and the relationship between karst cave water pressure and thickness of the rock pillar,it is proposed that rock pillar thickness with a safety factor equal to 1.5 is regarded as the calculated safety thickness of the rock pillar, which should be equal to the sum of the blasthole depth, blasting disturbance depth and the calculated safety thickness of the rock pillar. The cause of the karst water inrush at Qiyi Mine is that the rock pillar was so small that it did not possess a safety margin. Combining fluid–solid coupling theory, catastrophic theory and strength reduction method to study the nonlinear mechanical response of complicated rock engineering, new avenues for quantitative analysis of rock engineering stability evaluation should be forthcoming. 展开更多
关键词 Rock mechanics Catastrophic theory Shear strength reduction method Karst water inrush Safety factor
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Improved Ligand-Field Theory with Effect of Electron-Phonon Interaction 被引量:1
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作者 MADong-Ping CHENJu-Ron 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期529-538,共10页
Traditional ligand-field theory has to be improved by taking into account both 'pure electronic' contribution and electron-phonon interaction one (including lattice-vibrational relaxation energy). By means of ... Traditional ligand-field theory has to be improved by taking into account both 'pure electronic' contribution and electron-phonon interaction one (including lattice-vibrational relaxation energy). By means of improved ligand-field theory, R1, R2, R'3, R'2, and R'1 lines, U band, ground-state zero-field-splitting (GSZFS), and ground-state g factors of ruby and/or GSGG: Cr3+ as well as thermal shifts of GSZFS, R1 line and R2 line of ruby have been calculated.The results are in very good agreement with the experimental data. Moreover, it is found that the value of cubic-field parameter given by traditional ligand-field theory is inappropriately large. For thermal shifts of GSZFS, R1 line and R2 line of ruby, several conclusions have also been obtained. 展开更多
关键词 improved ligand-field theory electron-phonon interaction Stokes shift energy spectrum thermal shift g factor
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On Applicability of Face——Saving Theory in China
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作者 刘倩雅 《海外英语》 2013年第9X期202-203,共2页
Brown and Levinson's face theory is a theory of interpersonal relationship. It has successfully explained the influence of "face"in people's daily communications. The theory is built on the basis of ... Brown and Levinson's face theory is a theory of interpersonal relationship. It has successfully explained the influence of "face"in people's daily communications. The theory is built on the basis of western culture and ignores the cultural difference of "face"in China. It is not free from limitations the absoluteness of which exerts a checking effort on its universal applicability. This paper probes from the perspective of the influence of context and culture that the application of Face-Saving theory in actual communications in China, especially from those restrictions on the use of negative face in China. 展开更多
关键词 face—saving theory application restricting factors
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Research on Influence Factors of Pig Farmers' Ecological Farming Behavior: Based on the TPB and SEM
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作者 Chengying HAN Zhenhong QI +1 位作者 Dongmin ZHANG Xinrui LI 《Asian Agricultural Research》 2016年第2期19-27,共9页
China's extensive development model of pig industry gives rise to serious resource and environment bottleneck restriction,it is urgent to transform the existing development model into ecological farming model. In ... China's extensive development model of pig industry gives rise to serious resource and environment bottleneck restriction,it is urgent to transform the existing development model into ecological farming model. In this process,farmers' behavior will play a key role. On the basis of summarizing development connotation and characteristics of ecological agriculture,using survey data of 323 pig farmers in 6 provinces,based on the Theory of Planned Behavior( TPB) it introduced individual characteristics and external environment constraint variables,and made an empirical analysis on factors influencing intention and behavior of pig farmers' ecological farming using the Structural Equation Model( SEM). Results indicate:( i) ecological farming intention of pig farmers has the largest direct effect on their ecological farming behavior;( ii)ecological farming cognition of pig farmers has significant positive effect on their ecological farming behavior;( iii) external environment has the largest indirect effect on their ecological farming behavior,followed by the overall effect,and external environment has significant positive effect on ecological farming attitude and cognition of pig farmers;( iv) individual characteristics( educational level and income level) of pig farmers influence ecological farming behavior of pig farmers through their ecological farming attitude and intention,but the degree of influence is limited. 展开更多
关键词 Ecological FARMING BEHAVIOR Influence factors PIG FARMERS theory of PLANNED Behavior(TPB) Structural Equation Model(SEM)
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Energy Spectrum, g Factors, Strain-Induced Level-Splittings and R-Line Thermal Shift of MgO:V^(2+)
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作者 ZHANG Zheng-Jie MA Dong-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期511-516,共6页
Traditional ligand-field theory has to be improved by taking into account both pure electronic contribution and electron-phonon interaction one (including lattice-vibrational relaxation energy). By means of improved... Traditional ligand-field theory has to be improved by taking into account both pure electronic contribution and electron-phonon interaction one (including lattice-vibrational relaxation energy). By means of improved ligand-field theory, the R line, t^322T1 and t^322T2 lines, t^22(^3T1)e^4T2, t^22(^3T1)e^4T1 and t2e^2(^4A2)4T1 bands, g factors of t^32 ^4A2 and t32E, four strain-induced level-splittings and R-line thermal shift of MgO:V^2+ have been calculated. The results are in very good agreement with the experimental data. It is found that for MgO:V^2+, the contributions due to electronphonon interaction (EPI) come from the first-order term; the contributions from the second-order and higher terms are insignificant. In thermal shift of R line of MgO:V^2+, the temperature-dependent contribution due to EPI is dominant. The results obtained in this work may be used in theoretical calculations of other effects of EPI. 展开更多
关键词 improved ligand-field theory electron-phonon interaction energy spectrum strain-induced split-ting thermal shift g factor
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Analytical Solution for Bending Stress Intensity Factor from Reissner’S Plate Theory
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作者 Lalitha Chattopadhyay 《Engineering(科研)》 2011年第5期517-524,共8页
Plate-type structural members are commonly used in engineering applications like aircraft, ships nuclear reactors etc. These structural members often have cracks arising from manufacture or from material defects or st... Plate-type structural members are commonly used in engineering applications like aircraft, ships nuclear reactors etc. These structural members often have cracks arising from manufacture or from material defects or stress concentrations. Designing a structure against fracture in service involves consideration of strength of the structure as a function of crack size, dimension and the applied load based on principles of fracture mechanics. In most of the engineering structures the plate thickness is generally small and in these cases though the classical plate theory has provided solutions, the neglect of transverse shear deformation leads to the limitation that only two conditions can be satisfied on any boundary whereas we have three physical boundary conditions on an edge of a plate. In this paper this incompatibility is eliminated by using Reissner plate theory where the transverse shear deformation is included and three physically natural boundary conditions of vanishing bending moment, twisting moment and transverse shear stress are satisfied at a free boundary. The problem of estimating the bending stress distribution in the neighbourhood of a crack located on a single line in an elastic plate of varying thickness subjected to out-of-plane moment applied along the edges of the plate is examined. Using Reissner’s plate theory and integral transform technique, the general formulae for the bending moment and twisting moment in an elastic plate containing cracks located on a single line are derived. The thickness depended solution is obtained in a closed form for the case in which there is a single crack in an infinite plate and the results are compared with those obtained from the literature. 展开更多
关键词 REISSNER Plate theory INTEGRAL TRANSFORM Stress INTENSITY Factor SINGULAR INTEGRAL Equation
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Conversion of Torpedo's Lake and Sea Test Data Based on Grey System Theory 被引量:1
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作者 宋保维 邵成 +1 位作者 朱红波 毛昭勇 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第4期285-287,共3页
As only a little information can be obtained from torpedo's lake and sea tests,and the torpedo's life does not distribute typically. If conventional methods are used to convert the environment factor for torpe... As only a little information can be obtained from torpedo's lake and sea tests,and the torpedo's life does not distribute typically. If conventional methods are used to convert the environment factor for torpedo's lake and sea tests,their results can not reflect the actual conditions. A conversion model of the environment factor for torpedo's lake and sea tests is set up based on the GM(1,2) model of the grey system theory. For the merit of the grey system,the problem of uncertain life distributions and few samples can be solved. The calculation results show that the method is easy,realistic and high precise. 展开更多
关键词 鱼雷 理论 设计 计算 结构 雷体
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Research on the Influence Factors and Struction of University Teachers Leader-Member Exchange
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作者 Cuihua Liu 《International English Education Research》 2014年第3期65-68,共4页
The leader - member exchange theory is one of the leading and the hot topic in recent years of the study of Western leaders. Structural studies of LMX factors have important theoretical and practical value in college ... The leader - member exchange theory is one of the leading and the hot topic in recent years of the study of Western leaders. Structural studies of LMX factors have important theoretical and practical value in college teachers. In this paper, the "impact factor structure of university teachers LMX Questionnaire" for four universities 808 subjects was investigated. By exploratory factor analysis and confirmatory factor analysis, it found that the structure of university teachers LMX factors includes five dimensions: values, attitudes up, personality characteristics, switching behavior, objective situations. The questionnaire has good reliability and validity. 展开更多
关键词 University Teachers LMX theory Structural factors
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The application and view of the geochemistry theory in direct coal liquefaction technique 被引量:1
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作者 Xiaohong XIA Yong QIN 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期55-55,共1页
关键词 地球化学 液化现象 迁移
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