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Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source
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作者 LIU Yao CHEN Yifan GE Changzi 《Journal of Ocean University of China》 CAS CSCD 2024年第1期247-254,共8页
The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is ... The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying capacity.Simple and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of biodeposition.Theoretically,biodeposition in cage culture areas without specific emission rules can be simplified as point source pollution.Fluent is a fluid simulation software that can simulate the dispersion of particulate matter simply and efficiently.Based on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid software.In the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling fluxes.At sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),respectively.The simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),respectively.There was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well simulated.Moreover,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative error.Thus,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition in the open waters can be simply and effectively simulated by the fluid simulation software Fluent. 展开更多
关键词 fluent fluid simulation software pollution source simplification posterior difference ratio similarity theory Spear-man correlation
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ESTIMATION METHOD FOR AIRCRAFT SIMILARITY BASED ON FUZZY THEORY AND GREY INCIDENCE ANALYSIS 被引量:4
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作者 李永平 陈闵叶 刘明 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期194-198,共5页
An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the... An estimation method for aircraft similarity based on fuzzy theory and grey incidence analysis is presented. This estimation method is made up of the triangular fuzzy transforming model of linguistic variables and the method of grey incidence analysis. Nine feature attributes of aircraft are selected to estimate the similarity between the new aircraft and the existing aircraft. A new aircraft X and other six existing aircrafts are taken as examples. Analyses show that similarity estimation results obtained from the method are in accordance with practice. 展开更多
关键词 aircraft similarity fuzzy theory grey incidence analysis
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Load Reduction Test Method of Similarity Theory and BP Neural Networks of Large Cranes 被引量:4
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作者 YANG Ruigang DUAN Zhibin +2 位作者 LU Yi WANG Lei XU Gening 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第1期145-151,共7页
Static load tests are an important means of supervising and detecting a crane's lift capacity. Due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solv... Static load tests are an important means of supervising and detecting a crane's lift capacity. Due to space restrictions, however, there are difficulties and potential danger when testing large bridge cranes. To solve the loading problems of large-tonnage cranes during testing, an equivalency test is proposed based on the similarity theory and BP neural networks. The maximum stress and displacement of a large bridge crane is tested in small loads, combined with the training neural network of a similar structure crane through stress and displacement data which is collected by a physics simulation progressively loaded to a static load test load within the material scope of work. The maximum stress and displacement of a crane under a static load test load can be predicted through the relationship of stress, displacement, and load. By measuring the stress and displacement of small tonnage weights, the stress and displacement of large loads can be predicted, such as the maximum load capacity, which is 1.25 times the rated capacity. Experimental study shows that the load reduction test method can reflect the lift capacity of large bridge cranes. The load shedding predictive analysis for Sanxia 1200 t bridge crane test data indicates that when the load is 1.25 times the rated lifting capacity, the predicted displacement and actual displacement error is zero. The method solves the problem that lifting capacities are difficult to obtain and testing accidents are easily possible when 1.25 times related weight loads are tested for large tonnage cranes. 展开更多
关键词 similarity theory BP neural network large bridge crane load reduction equivalent test method
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Progress in ab initio in-medium similarity renormalization group and coupled-channel method with coupling to the continuum
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作者 Xin‑Yu Xu Si‑Qin Fan +4 位作者 Qi Yuan Bai‑Shan Hu Jian‑Guo Li Si‑Min Wang Fu‑Rong Xu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第12期312-342,共31页
Over the last decade,nuclear theory has made dramatic progress in few-body and ab initio many-body calculations.These great advances stem from chiral efective feld theory(xEFT),which provides an efcient expansion and ... Over the last decade,nuclear theory has made dramatic progress in few-body and ab initio many-body calculations.These great advances stem from chiral efective feld theory(xEFT),which provides an efcient expansion and consistent treatment of nuclear forces as inputs of modern many-body calculations,among which the in-medium similarity renormalization group(IMSRG)and its variants play a vital role.On the other hand,signifcant eforts have been made to provide a unifed description of the structure,decay,and reactions of the nuclei as open quantum systems.While a fully comprehensive and microscopic model has yet to be realized,substantial progress over recent decades has enhanced our understanding of open quantum systems around the dripline,which are often characterized by exotic structures and decay modes.To study these interesting phenomena,Gamow coupled-channel(GCC)method,in which the open quantum nature of few-body valence nucleons coupled to a deformed core,has been developed.This review focuses on the developments of the advanced IMSRG and GCC and their applications to nuclear structure and reactions. 展开更多
关键词 Ab initio calculations Chiral efective feld theory In-medium similarity renormalization group Gamow coupled channel Resonance and continuum Open quantum systems
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Similarity theory based method for MEMS dynamics analysis 被引量:2
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作者 李瑰贤 彭云峰 张欣 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第3期312-316,共5页
A new method for MEMS dynamics analysis is presented,ased on the similarity theory. With this method, two systems' similarities can be captured in terms of physics quantities/governed-equations amongst different e... A new method for MEMS dynamics analysis is presented,ased on the similarity theory. With this method, two systems' similarities can be captured in terms of physics quantities/governed-equations amongst different energy fields, and then the unknown dynamic characteristics of one of the systems can be analyzed according to the similar ones of the other system. The probability to establish a pair of similar systems among MEMS and other energy systems is also discussed based on the equivalent between mechanics and electrics, and then the feasibility of applying this method is proven by an example, in which the squeezed damping force in MEMS and the current of its equivalent circuit established by this method are compared. 展开更多
关键词 similarity theory MEMS dynamics equivalent between mechanics and electrics equivalent circuit
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The Application of Similarity Theory in Designing Large Deflection Buckling Spring-Piece
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作者 Huang Tiequn Jia Shushi Sun Yueming Cheng Yaodong 《上海交通大学学报》 EI CAS CSCD 北大核心 2004年第z2期42-47,共6页
Large Deflection Buckling Spring-Piece (LDBSP) refers to the deformation of an end-fixed flat spring-piece under normal loadings. Plastic deformation usually appears in LDBSP.The static characteristic curve is very pa... Large Deflection Buckling Spring-Piece (LDBSP) refers to the deformation of an end-fixed flat spring-piece under normal loadings. Plastic deformation usually appears in LDBSP.The static characteristic curve is very particular, because within its linear deflection region, the spring constant can be designed to be any value from minus to plus. With its obvious advantages of large liner deflection range, low spring constant, etc., the LDBSP has now been extensively applied to the exciting device, low-frequency shock absorbers and so on. The static characteristic curve of LDBSP belongs to the nonlinear problem of an arch with varying section. Therefore, it is difficult to obtain it theoretically. The formulae for designing LDBSP have not been set up yet. In this study,the authors apply similarity theory to analyze the liner deflection range A and the spring constant K, and derive the relationship of similarity criterion, finally obtain a set of formulae for designing LDBSP by model test and the least square method, which can be applied in engineering design.Through the research, it is proved that it is unnecessary to keep geometrical similarity of spring-piece shape. This fact extends the application scope of the formulae. The proposed formulae for designing LDBSP thereby can be applied for any dimensions within the range allowed. 展开更多
关键词 similarity theory similarity CRITERION dimension model test DEFLECTION SPRING SPRING constant plastic deformation
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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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Similarities and Differences of Chinese Translation Theories And Western Translation Theories 被引量:14
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作者 黄雯怡 《海外英语》 2017年第2期241-244,共4页
Translation theories are based on the different languages and cultures.The difference is not clearly defined,so there is a place of mutual integration that can be used interchangeably.Theyall regard author’s meaning ... Translation theories are based on the different languages and cultures.The difference is not clearly defined,so there is a place of mutual integration that can be used interchangeably.Theyall regard author’s meaning and style as a core to translate a good product.Comparatively,Chinese theories focus on expressing the general meaning of the author,but Western theory emphasizes equivalence of details on translation and response of reader.In the translation practice,according to different theoretical texts and different stages of the translation process,the Chinese and Western translation theories are combined to apply them for making up for each other's deficiencies,which can help our translators to solve the problems in the process of translation improve the construction of Chinese theories. 展开更多
关键词 chinese translation theories western translation theories similarITIES DIFFERENCES
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Combination method of conflict evidences based on evidence similarity 被引量:9
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作者 Wenhao Bi An Zhang Yuan Yuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期503-513,共11页
Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure ... Aiming at the problem that the traditional Dempster Shafer (D-S) evidence theory cannot deal with conflicted evidences effectively and correctly, this paper points out that the key issue of this problem is to measure the degree of conflict between evidences correctly after analyzing various improved methods. The existing evidence conflict measure methods are analyzed, and a new evidence conflict measure method called evidence similarity measure based on the Tanimoto measure is proposed, while a new evidence combination method is proposed on the basis of evidence similarity measure. Firstly, the conflict degrees between evidences are obtained through the evidence similarity measure. Then the evidence sources are modified based on the credibility of different evidences and the weights of conflicted parts of evidences on different focal elements are determined. Finally, the fusion result is obtained by this method. Numerical examples show that the proposed method can effectively fuse evidences when evidences are consistent or highly conflicted, and it has a fast convergence speed, a high degree of accuracy and good adaptability. 展开更多
关键词 evidence theory evidence conflict conflict measure evidence similarity information fusion
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Observational Evidence for the Monin-Obukhov Similarity under All Stability Conditions 被引量:3
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作者 牛生杰 赵丽娟 +3 位作者 陆春松 杨军 王静 王巍巍 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第2期285-294,共10页
Data collected in the surface layer in a northern suburban area of Nanjing from 15 November to 29 December 2007 were analyzed to examine the MoninObukhov similarity for describing the turbulent fluctu ations of 3D win... Data collected in the surface layer in a northern suburban area of Nanjing from 15 November to 29 December 2007 were analyzed to examine the MoninObukhov similarity for describing the turbulent fluctu ations of 3D winds under all stability conditions and to obtain the turbulence characteristics under different weather conditions. The results show that the dimensionless standard deviations of turbulent velocity com ponents (σ u /u* , σ v /u* , σ w /u * ) and dimensionless turbulent kinetic energy (TKE) can be well described by "1/3" power law relationships under stable, neutral, and unstable conditions, with σ u /u * σ v /u * σ w /u* . Land use and land cover changes mainly impact dimensionless standard deviations of horizontal component fluctuations, but they have very little on those of the vertical component. The dimensionless standard devi ations of wind components and dimensionless TKE are remarkably affected by different weather conditions; the deviations of horizontal wind component and dimensionless TKE present fog day clear sky overcast cloudy; the trend of the vertical wind component is the reverse. The surface drag coefficient at a Nan jing suburban measurement site during the observation period was obviously higher than at other reported plains and plateau areas, and was approximately one order larger in magnitude than the reported plains areas. Dimensionless standard deviation of temperature declined with increasing |z /L| with an approximate "1/3" slope in unstable stratification and "2/3" slope in stable stratification. 展开更多
关键词 Monin-Obukhov similarity theory boundary stability boundary layer parameterization
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Scale Effects and a Method for Similarity Evaluation in Micro Electrical Discharge Machining 被引量:1
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作者 LIU Qingyu ZHANG Qinhe +3 位作者 WANG Kan ZHU Guang FU Xiuzhuo ZHANG Jianhua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1193-1199,共7页
Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at th... Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of "scale effects" in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM. 展开更多
关键词 Electrical Discharge Machining (EDM) micro EDM Scale effect similarity theory similarity evaluating method
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Complex neutrosophic generalised dice similarity measures and their application to decision making 被引量:2
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作者 Zeeshan Ali Tahir Mahmood 《CAAI Transactions on Intelligence Technology》 2020年第2期78-87,共10页
Complex neutrosophic set(CNS)is a modified version of the complex fuzzy set,to cope with complicated and inconsistent information in the environment of fuzzy set theory.The CNS is characterised by three functions expr... Complex neutrosophic set(CNS)is a modified version of the complex fuzzy set,to cope with complicated and inconsistent information in the environment of fuzzy set theory.The CNS is characterised by three functions expressing the degree of complex-valued membership,complex-valued abstinence and degree of complex-valued non-membership.The aim of this manuscript is to initiate the novel dice similarity measures and generalised dice similarity using CNS.The special cases of the investigated measures are discussed with the help of some remarks.Moreover,some distance measures based on CNS are also proposed in this manuscript.Then,the authors applied the generalised dice similarity measures and weighted generalised dice similarity measures using CNS to the pattern recognition model to examine the reliability and superiority of the established approaches.The advantages and comparative analysis of the proposed measures with existing measures are also discussed in detail.At last,a numerical example is provided to illustrate the validity and applicability of the presented measures. 展开更多
关键词 theory. similarity VALUED
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IMPROVEMENT TO THE EVAPORATION DUCT MODEL BY INTRODUCING NONLINEAR SIMILARITY FUNCTIONS IN STABLE CONDITIONS 被引量:1
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作者 丁菊丽 费建芳 +2 位作者 黄小刚 胡晓华 周鑫 《Journal of Tropical Meteorology》 SCIE 2011年第1期64-72,共9页
Modified refractivity (M) profile is an important parameter to describe the atmospheric refraction environment,as well as a key factor in uniquely evaluating electromagnetic propagation effects.In order to improve the... Modified refractivity (M) profile is an important parameter to describe the atmospheric refraction environment,as well as a key factor in uniquely evaluating electromagnetic propagation effects.In order to improve the model-derived M profile in stable (especially very stable) conditions,three nonlinear similarity functions,namely BH91,CB05,SHEBA07,are introduced in this paper to improve the original Babin_V25 model,and the performances of these modified models are verified based on the hydrometeorological observations from tower platforms,which are finally compared with the original Babin_V25 model and Local_HYQ92 model.Results show that introducing nonlinear similarity functions can significantly improve the model-derived M profile;especially,the newly developed SHEBA07 functions manage to reduce the predicted root mean square (rms) differences of M and M slope (for both 0-5m and 5-40m) by 64.5%,16.6%,and 60.4%,respectively in stable conditions.Unfortunately,this improved method reacts little on the evaporation duct height;in contrast,Local_HYQ92 model is capable of reducing the predicted rms differences of M,M slope (for both 0-5m and 5-40m),and evaporation duct height by 76.7%,40.2%,83.7%,and 58.0% respectively.Finally,a new recommendation is made to apply Local_HYQ92 and Babin_SHEBA07 in very stable conditions considering that M slope is more important than evaporation duct height and absolute M value in uniquely determining electromagnetic propagation effects. 展开更多
关键词 evaporation duct similarity theory flux-profile relationship nondimensional similarity functions stable boundary layer electromagnetic wave propagation radar detective ability
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Numerical verification of similar Cam-clay model based on generalized potential theory 被引量:2
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作者 钟志辉 杨光华 +2 位作者 傅旭东 温勇 张玉成 《Journal of Central South University》 SCIE EI CAS 2014年第12期4707-4713,共7页
From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential ... From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential theory, has less assumptions,clearer mathematical basis, and better computational accuracy. Theoretically, it is more scientific than the traditional Cam-clay models. The particle flow code PFC3 D was used to make numerical tests to verify the rationality and practicality of the similar Cam-clay model. The verification process was as follows: 1) creating the soil sample for numerical test in PFC3 D, and then simulating the conventional triaxial compression test, isotropic compression test, and isotropic unloading test by PFC3D; 2)determining the parameters of the similar Cam-clay model from the results of above tests; 3) predicting the sample's behavior in triaxial tests under different stress paths by the similar Cam-clay model, and comparing the predicting results with predictions by the Cam-clay model and the modified Cam-clay model. The analysis results show that the similar Cam-clay model has relatively high prediction accuracy, as well as good practical value. 展开更多
关键词 generalized potential theory similar Cam-clay model modified Cam-clay model numerical test PFC3D
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Design and Research of Similarity and its Serialization of the Flotation Machine's Key Structure 被引量:1
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作者 DONG Yu-de DING Zhan-you +2 位作者 YANG Shan-lai BAI Su-cheng PAN Kai 《Computer Aided Drafting,Design and Manufacturing》 2014年第2期74-81,共8页
Aiming at the problems such as more repeatedly design and longer design cycle, in this paper, the similarity theory was introduced to the design process of the key structures of flotation machine. The impeller and U-s... Aiming at the problems such as more repeatedly design and longer design cycle, in this paper, the similarity theory was introduced to the design process of the key structures of flotation machine. The impeller and U-shaped tank of flotation machine system were analyzed as similarity unit. Meanwhile, the level of similarity of the units and the similarity of the system were calculated. Based on the analysis of the impeller and the size of U-shaped tank, the similarity criteria were derived. The derived conclusions are: (1) The relationship between the diameter of the impeller and the volume of the tank was power function and calculated as the similarity criteria of the impeller; (2) The relationship between the ratio between the U-shaped tank's cross-sectional area and impeller's diameter and the volume of the tank was power function and calculated as the similarity criterions of the U-shaped tank. Using the similarity criterion combined with computer technology and database technology to realize part and system serialization design. The results show that the research can efficiency. avoid repeatedly design, shorten design cycle, and raise the design 展开更多
关键词 SCM similarity theory similarity unit flotation machine SERIALIZATION
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论信息技术革命的社会历史原因——基于SST理论的分析 被引量:4
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作者 鄢显俊 《科学学研究》 CSSCI 北大核心 2005年第5期586-591,共6页
信息技术革命所以发生在20世纪40年代末到90年代初期的美国,与特定历史时期的社会背景有关,SST理论为剖析信息技术革命的社会历史原因提供了一种全面而深刻的理论框架。该理论认为,技术革命与社会之间是一种良性互动的关系,但相较而言,... 信息技术革命所以发生在20世纪40年代末到90年代初期的美国,与特定历史时期的社会背景有关,SST理论为剖析信息技术革命的社会历史原因提供了一种全面而深刻的理论框架。该理论认为,技术革命与社会之间是一种良性互动的关系,但相较而言,现代社会对技术进步的决定作用尤显突出,这表现为:社会的政治需求、经济需求以及两者综合作用而产生的官—产—学—研一体化制度保障和完善的风险投资体制决定了信息技术革命必然发生在美国,它是“历史合力”的结果。 展开更多
关键词 信息技术革命 社会历史原因 sst理论
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基于SST和Bayes的初始备件需求确定方法 被引量:6
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作者 董骁雄 陈云翔 +1 位作者 项华春 白洋 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2018年第2期316-321,共6页
随着使用环境的变化,研制阶段制定的初始备件方案常常无法满足装备部署部队后的保障要求。针对该情况,引入了相似系统理论(SST)和Bayes方法,根据相似系统理论初步确定备件的初始失效率,依据装备在使用中的寿命分布类型,取出对应的共轭... 随着使用环境的变化,研制阶段制定的初始备件方案常常无法满足装备部署部队后的保障要求。针对该情况,引入了相似系统理论(SST)和Bayes方法,根据相似系统理论初步确定备件的初始失效率,依据装备在使用中的寿命分布类型,取出对应的共轭先验分布,利用最大熵方法求取超参数,运用Bayes理论得到后验失效率,综合初始失效率和后验失效率确定初始备件需求。算例结果表明该方法满足实际应用要求,是初始备件需求预测可靠而有效的方法。 展开更多
关键词 初始备件 相似系统理论(sst) BAYES 需求 失效率
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Application of Fractal Theory in Landscape Design
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作者 王雨竹 《Journal of Landscape Research》 2012年第3期29-31,共3页
Research and application of fractal theory in landscape design has greatly enriched the concepts and techniques of garden creation,and pushed forward landscape design closer to the natural world.By elaborating interna... Research and application of fractal theory in landscape design has greatly enriched the concepts and techniques of garden creation,and pushed forward landscape design closer to the natural world.By elaborating internal connection between fractal theory and landscape design,this paper uses iterative function system of the fractal theory and matlab to draw fractal trees.Two designed experiments demonstrate that the fractal theory can be employed to realize the vivid drawing of natural landscapes with the support of limited data.Therefore,fractal theory is a practical tool used to draw vivid natural landscapes efficiently. 展开更多
关键词 LANDSCAPE architecture LANDSCAPE design FRACTAL theory SELF-similarity ITERATIVE FUNCTION system Matlab
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考虑AIR情形的方案选择方法研究——基于IFSST与TOPSIS
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作者 尤天慧 曹兵兵 夏波 《软科学》 CSSCI 北大核心 2016年第9期131-135,共5页
针对多方参与决策(A)、评价指标集有差异(I)且专家对指标参数有要求(R)的方案选择问题,给出了一种基于直觉模糊软集理论(IFSST)和逼近理想点(TOPSIS)的决策方法。首先,描述了考虑AIR情形的方案选择问题,并依据IFSST,将评价信息转化为直... 针对多方参与决策(A)、评价指标集有差异(I)且专家对指标参数有要求(R)的方案选择问题,给出了一种基于直觉模糊软集理论(IFSST)和逼近理想点(TOPSIS)的决策方法。首先,描述了考虑AIR情形的方案选择问题,并依据IFSST,将评价信息转化为直觉模糊软集的形式,通过直觉模糊软集间的且运算,获得每个方案针对各方评审专家评价信息的综合直觉模糊软集;然后,依据TOPSIS的思想,确定综合直觉模糊软集的正、负理想点;进一步,计算各备选方案到正、负理想点的距离及与理想点的贴近度,并基于理想点贴近度大小选择最优备选方案;最后,通过一个算例说明方法的可行性与有效性。 展开更多
关键词 多方参与(A) 差异评价指标集(I) 指标参数要求(R) IFsst TOPSIS
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Risk assessment model of tunnel water inrush based on improved attribute mathematical theory 被引量:10
20
作者 YANG Xiao-li ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期379-391,共13页
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel... Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility. 展开更多
关键词 tunnel water inrush risk assessment model attribute mathematical theory nonlinear measurement function similar weight method
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