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Three-dimensional structural models,evolution and petroleum geological significances of transtensional faults in the Ziyang area,central Sichuan Basin,SW China
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作者 TIAN Fanglei GUO Tonglou +6 位作者 HE Dengfa GU Zhanyu MENG Xianwu WANG Renfu WANG Ying ZHANG Weikang LU Guo 《Petroleum Exploration and Development》 SCIE 2024年第3期604-620,共17页
With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,... With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,fault throw analyzing,and balanced profile restoration,it is pointed out that the transtensional fault system in the Ziyang 3-D seismic survey consists of the northeast-trending F_(I)19 and F_(I)20 fault zones dominated by extensional deformation,as well as 3 sets of northwest-trending en echelon normal faults experienced dextral shear deformation.Among them,the F_(I)19 and F_(I)20 fault zones cut through the Neoproterozoic to Lower Triassic Jialingjiang Formation,presenting a 3-D structure of an“S”-shaped ribbon.And before Permian and during the Early Triassic,the F_(I)19 and F_(I)20 fault zones underwent at least two periods of structural superimposition.Besides,the 3 sets of northwest-trending en echelon normal faults are composed of small normal faults arranged in pairs,with opposite dip directions and partially left-stepped arrangement.And before Permian,they had formed almost,restricting the eastward growth and propagation of the F_(I)19 fault zone.The F_(I)19 and F_(I)20 fault zones communicate multiple sets of source rocks and reservoirs from deep to shallow,and the timing of fault activity matches well with oil and gas generation peaks.If there were favorable Cambrian-Triassic sedimentary facies and reservoirs developing on the local anticlinal belts of both sides of the F_(I)19 and F_(I)20 fault zones,the major reservoirs in this area are expected to achieve breakthroughs in oil and gas exploration. 展开更多
关键词 transtensional(strike-slip)fault three-dimensional structural model structural evolution petroleum geological significance Ziyang area Sichuan Basin
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An experimental study on variation of b value during deformation of rock samples with different structural models
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作者 陈顺云 刘力强 +1 位作者 马胜利 马瑾 《Acta Seismologica Sinica(English Edition)》 CSCD 2005年第3期338-344,共7页
A preliminary study of b value of rocks with two kinds of structural models has been made on the base of a new acoustic emission recording system. It shows that b value of the sample decreases obviously when the sampl... A preliminary study of b value of rocks with two kinds of structural models has been made on the base of a new acoustic emission recording system. It shows that b value of the sample decreases obviously when the sample with compressive en echelon faults changes into a tensile one after interchange occurs between stress axis σ1 and σ2. A similar experiment is observed when the sample with tensile en echelon faults changes into that with a bend fault after two segments of the en echelon fault linking up. These facts indicate that the variation of b value may con-tain the information of the regional dominant structural model. Therefore, b-value analyses could be a new method for studying regional dominant structural models. 展开更多
关键词 b value of acoustic emission structural model en echelon fault bend fault
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Quantitative Structural Models to Assess Credit Risk on Individuals
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作者 Akorede K. Oluwo Enrique Villamor 《Journal of Applied Mathematics and Physics》 2022年第7期2313-2340,共28页
Default Probabilities quantitatively measures the credit risk that a borrower will be unable or unwilling to repay its debt. An accurate model to estimate, as a function of time, these default probabilities is of cruc... Default Probabilities quantitatively measures the credit risk that a borrower will be unable or unwilling to repay its debt. An accurate model to estimate, as a function of time, these default probabilities is of crucial importance in the credit derivatives market. In this work, we adapt Merton’s [1] original works on credit risk, consumption and portfolio rules to model an individual wealth scenario, and apply it to compute this individual default probabilities. Using our model, we also compute the time depending individual default intensities, recovery rates, hazard rate and risk premiums. Hence, as a straight-forward application, our model can be used as novel way to measure the credit risk of individuals. 展开更多
关键词 Merton structural Model Individual Default Intensities Hazard Rate for Individuals Individual Risk Premium
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Understanding size selectivity of trawls using structural models:Methodology and a case study on fish sorting grids
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作者 Nadine Jacques Bent Herrmann +1 位作者 Jesse Brinkhof Manu Sistiaga 《Aquaculture and Fisheries》 2025年第3期499-513,共15页
Fish behaviour affects the performance of selection devices in fishing gears.Traditionally,fish behaviour in relation to selection devices is assessed by direct observation.However,this approach has limitations,and th... Fish behaviour affects the performance of selection devices in fishing gears.Traditionally,fish behaviour in relation to selection devices is assessed by direct observation.However,this approach has limitations,and the observations are not explicitly incorporated in the selectivity models.Further,underwater observations and quantification of fish behaviour can be challenging.In this study we outline and use an indirect method to explicitly incorporate and quantify fish behaviour in trawl selectivity analysis.We use a set of structural models,which are based on modelling the actual processes believed to determine the size selection of the device,to discern which behaviours are most likely to explain the selectivity process.By bootstrapping we assess how confident we can be in the choice of a specific structural model and on discerning the associated behavioural aspects.We collected size selectivity data in the Barents Sea demersal trawl fishery targeting gadoids,where the use of a sorting grid is compulsory.Using our modelling approach,we obtained deeper understanding of which behavioural processes most likely affect size selectivity in the sorting grids tested.Our approach can be applied to other fishing gears to understand and quantify fish behaviour in relation to size selectivity. 展开更多
关键词 structural models Size selectivity Fish behaviour Bootstrap model selection Bottom trawl Sorting grids
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A Re-Parametrization-Based Bayesian Differential Analysis Algorithm for Gene Regulatory Networks Modeled with Structural Equation Models
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作者 Yan Li Dayou Liu +1 位作者 Yungang Zhu Jie Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第7期303-313,共11页
Under different conditions,gene regulatory networks(GRNs)of the same gene set could be similar but different.The differential analysis of GRNs under different conditions is important for understanding condition-specif... Under different conditions,gene regulatory networks(GRNs)of the same gene set could be similar but different.The differential analysis of GRNs under different conditions is important for understanding condition-specific gene regulatory relationships.In a naive approach,existing GRN inference algorithms can be used to separately estimate two GRNs under different conditions and identify the differences between them.However,in this way,the similarities between the pairwise GRNs are not taken into account.Several joint differential analysis algorithms have been proposed recently,which were proved to outperform the naive approach apparently.In this paper,we model the GRNs under different conditions with structural equation models(SEMs)to integrate gene expression data and genetic perturbations,and re-parameterize the pairwise SEMs to form an integrated model that incorporates the differential structure.Then,a Bayesian inference method is used to make joint differential analysis by solving the integrated model.We evaluated the performance of the proposed re-parametrization-based Bayesian differential analysis(ReBDA)algorithm by running simulations on synthetic data with different settings.The performance of the ReBDA algorithm was demonstrated better than another state-of-the-art joint differential analysis algorithm for SEMs ReDNet obviously.In the end,the ReBDA algorithm was applied to make differential analysis on a real human lung gene data set to illustrate its applicability and practicability. 展开更多
关键词 Gene regulatory networks structural equation models JOINT
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Porosity prediction based on improved structural modeling deep learning method guided by petrophysical information
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作者 Bo-Cheng Tao Huai-Lai Zhou +3 位作者 Wen-Yue Wu Gan Zhang Bing Liu Xing-Ye Liu 《Petroleum Science》 2025年第6期2325-2338,共14页
Porosity is an important attribute for evaluating the petrophysical properties of reservoirs, and has guiding significance for the exploration and development of oil and gas. The seismic inversion is a key method for ... Porosity is an important attribute for evaluating the petrophysical properties of reservoirs, and has guiding significance for the exploration and development of oil and gas. The seismic inversion is a key method for comprehensively obtaining the porosity. Deep learning methods provide an intelligent approach to suppress the ambiguity of the conventional inversion method. However, under the trace-bytrace inversion strategy, there is a lack of constraints from geological structural information, resulting in poor lateral continuity of prediction results. In addition, the heterogeneity and the sedimentary variability of subsurface media also lead to uncertainty in intelligent prediction. To achieve fine prediction of porosity, we consider the lateral continuity and variability and propose an improved structural modeling deep learning porosity prediction method. First, we combine well data, waveform attributes, and structural information as constraints to model geophysical parameters, constructing a high-quality training dataset with sedimentary facies-controlled significance. Subsequently, we introduce a gated axial attention mechanism to enhance the features of dataset and design a bidirectional closed-loop network system constrained by inversion and forward processes. The constraint coefficient is adaptively adjusted by the petrophysical information contained between the porosity and impedance in the study area. We demonstrate the effectiveness of the adaptive coefficient through numerical experiments.Finally, we compare the performance differences between the proposed method and conventional deep learning methods using data from two study areas. The proposed method achieves better consistency with the logging porosity, demonstrating the superiority of the proposed method. 展开更多
关键词 Porosity prediction Deep learning Improved structural modeling Petrophysical information
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Structural Ore-controlling Model for the Super-large Hadamengou Gold Deposit in Inner Mongolia,China
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作者 WANG Da YANG Biao +8 位作者 XU Daxing LI Xiaoshuang FAN Songhao SU Panyun MA Huchao WANG Guilong WANG Gaotian MA Lei LIU Wencan 《Acta Geologica Sinica(English Edition)》 2025年第2期499-521,共23页
Controversy is ongoing regarding the relationship between ore formation and the structural evolution of the Hadamengou gold deposit.To address this issue,we conducted a comprehensive investigation of mineralization-re... Controversy is ongoing regarding the relationship between ore formation and the structural evolution of the Hadamengou gold deposit.To address this issue,we conducted a comprehensive investigation of mineralization-related structures,geochronology and Fe isotopes.From the perspective of spatial evolution,hydrothermal fluids originating from the Shadegai and Xishadegai plutons have extracted accumulated ore-forming elements from the Wulashan Group(Ar2WL)and then evolved,initiating at Exploration Line 11 and migrating eastwards and westwards along the EW-trending thrust fault system to form orebodies.From the temporal evolution standpoint,the Wulashan Group(Ar_(2)WL)experienced diagenesis(2591.00 Ma to 2204.00 Ma)and metamorphism(2074.00 Ma to 1625.00 Ma)from late Neoarchean to early Paleoproterozoic,when ore-forming materials were initially accumulated;in the early Paleozoic(440.71 Ma to 425.00 Ma),the collision led to the formation of early-stage EW-trending imbricated thrust faults,which established a fundamental structural framework for the orefield and further accumulated ore-forming materials;from the late Paleozoic to the Mesozoic,multiple subsequent episodes of regional tectonic-magmatic-hydrothermal events have superimposed,modified and reactivated the thrust fault system.Notably,the Triassic period,particularly between 245.00 Ma and 217.90 Ma,is considered to be a primary ore-forming stage.In summary,the intricate relationship between ore-formation and structural evolution has been fundamentally elucidated. 展开更多
关键词 Fe isotope GEOCHRONOLOGY thrust fault system structural ore-controlling model Hadamnegou Au deposit
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Factors in Work-Related Musculoskeletal Disorders in Dentists:A Structural Equation Model
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作者 Shunhang Li Jian Li +6 位作者 Xin Xu Yushan Huang Yilin Zhang Xiaoshuang Xu Weizhen Guan Xiaoping Liu Jing Li 《Biomedical and Environmental Sciences》 2025年第5期639-643,共5页
Dentistry is a profession with a high prevalence of work-related musculoskeletal disorders(WMSDs),with symptoms often appearing very early in one’s career[1].WMSDs are conditions affecting the muscles,bones,and nervo... Dentistry is a profession with a high prevalence of work-related musculoskeletal disorders(WMSDs),with symptoms often appearing very early in one’s career[1].WMSDs are conditions affecting the muscles,bones,and nervous system due to occupational factors.In 2002,the International Labor Organization included musculoskeletal diseases in the International List of Occupational Diseases.China’s recently updated Classification and Catalog of Occupational Diseases has introduced two new categories of occupational illnesses,including occupational musculoskeletal disorders.WMSDs significantly impact the health and work of dentists,reducing their quality of life and causing economic losses.These disorders are multifactorial in nature,influenced by personal,psychosocial,biomechanical,and environmental factors.Dentists frequently maintain static or awkward postures during procedures,which leads to musculoskeletal strain and discomfort;additionally,long working hours contribute to psychological stress,further increasing the risk of WMSDs[2]. 展开更多
关键词 DENTISTS occupational factors classification catalog occupational diseases musculoskeletal disorders wmsds awkward postures work related musculoskeletal disorders structural equation model static postures
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Structural Modeling and Aeroelastic Analysis of High-Aspect-Ratio Composite Wings 被引量:9
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作者 赵永辉 胡海岩 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第1期25-30,共6页
A unified structural model for high-aspect-ratio composite wing with arbitrary cross-section is developed. Two types of lay-ups of the composite wing, namely, circumferentially uniform stiffness (CUS) configuration ... A unified structural model for high-aspect-ratio composite wing with arbitrary cross-section is developed. Two types of lay-ups of the composite wing, namely, circumferentially uniform stiffness (CUS) configuration and circumferentially asymmetric stiffness (CAS) configuration, are investigated. The present structural modeling method is validated through ANSYS FEM software for the case of a composite box beam. Then, the case of a single-cell composite wing with NACA0012 airfoil shape is considered. To investigate the aeroelastic problem of high-aspect-ratio composite wings, the linear ONERA aerodynamic model is used to model the unsteady aerodynamic loads under the case of small angle of attack. Finally, flutter speeds of the high-aspect-ratio wing with various composite ply angles are determined by using U-g method. 展开更多
关键词 structural modeling aeroelastic analysis high-aspect-ratio composite wing
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EVOLUTIONARY MODEL OF FREE ECONOMIC ZONES——Different Generations and Structural Features 被引量:10
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作者 MENGGuang-wen 《Chinese Geographical Science》 SCIE CSCD 2005年第2期103-112,共10页
Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of... Free economic zone (FEZ) has a long history and plays a more and more important role in the world economy. Most studies, however, focused on the theoretical analysis of benefit and cost as well as the economic role of FEZ in the less developed countries and little attention has been paid to the evolution of FEZ. This paper will improve the above-mentioned studies and put forward the structural and spatial evolutionary model of FEZ by analyzing the development of objectives, preferential policy, governance structure, industrial sectors and location of FEZs based on the international economic and political development. FEZs develop towards: 1) more comprehensive and macro objectives, 2) more industry-oriented and multi-preferential policies, 3) more cross-national and combination zones with administrative areas, 4) more technology-intensive and multi-industries, 5) more flexible location and larger spatial dimensions, 6) more rapid evolution and typologies, and 7) more economic integration to the host economy. 展开更多
关键词 free economic zone structural evolutionary model spatial evolution
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IFC-based integration tool for supporting information exchange from architectural model to structural model 被引量:5
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作者 刘照球 李云贵 张汉义 《Journal of Central South University》 SCIE EI CAS 2010年第6期1344-1350,共7页
With the purpose of enhancing effective collaboration between architects and structural engineers in the building design field, an integration tool was developed for supporting information exchange from architectural ... With the purpose of enhancing effective collaboration between architects and structural engineers in the building design field, an integration tool was developed for supporting information exchange from architectural model to structural model. The PKPM (Bopomofo acronym, a Chinese building design software) structural model and an industry foundation classes (IFC) data model were adopted and analyzed to design the framework of the integration tool. The technique of mixed program languages (C++ and FORTRAN) was applied to developing the tool software, and the connectivity relationships and intersection nodes between the structural elements were optimized and simplified. A case study was implemented to illustrate the method to use the integration tool for information exchange from IFC-format architectural model to PKPM structural model. The results show that the tool can extract the information of architectural model and form a corresponding structural model. The presented method can help to enhance the modeline efficiency at the structural design phase. 展开更多
关键词 architectural model structural model industry foundation classes informatiOn exchange
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Coupling Relationship Analysis on Households′ Production Behaviors and Their Influencing Factors in Nature Reserves:A Structural Equation Model 被引量:6
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作者 WANG Changhai WEN Yali +1 位作者 DUAN Wei HAN Feng 《Chinese Geographical Science》 SCIE CSCD 2013年第4期506-518,共13页
A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by inter... A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by interrelated factors,such as protection attitudes,resource endowment,and family wealth.This research evaluated households near the Crested Ibis National Nature Reserve in Shaanxi Province,acquiring data from 436 households around Yang County and Ningshan County in the south slope of Qinling Mountains,China.Based on the collected data,we developed a structural equation model to evaluate the coupling relationships among households′ protection attitudes,production behaviors,resource endowment,and family wealth.The results showed that:1) households with great resource endowment had more negative attitudes,probably due to their greater protection costs;2) the households with higher education levels had worse protection attitudes;3) the households with more family wealth were likely to use fewer fertilizers,pesticides,and firewood;4) the households with more resource endowment showed less production and management behaviors;5) the enhancement of households' attitudes improved production behaviors to protection the environment,but the effects were not statistically significant.Our results provide a basis for the government's protection policy making,exploring the effective management measures that are beneficial for both nature reserve management and community development. 展开更多
关键词 family wealth protection attitudes production behaviors resource endowment structural equation model Crested Ibis National Nature Reserve
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Framework system and research flow of uncertainty in 3D geological structure models 被引量:7
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作者 ZHU, Liangfeng ZHUANG, Zhiyi 《Mining Science and Technology》 EI CAS 2010年第2期306-311,共6页
Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error... Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error detection and dynamic correction in 3D geological structure models,we have reviewed the current situation and development trends in 3D geological modeling.The main context of uncertainty in 3D geological structure models is discussed.Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed.We have described in detail the integration of development practices of 3D geological modeling systems,as well as the implementation process for uncertainty evaluation in 3D geological structure models.This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions. 展开更多
关键词 3D geological structure model model quality UNCERTAINTY 3D geological modeling
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Investigation of the role of personal factors on work injury in underground mines using structural equation modeling 被引量:5
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作者 P.S.Paul 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期815-819,共5页
Work injuries in mines are complex and generally characterized by several factors starting from personal to technical and technical to social characteristics.In this paper,investigation was made through the applicatio... Work injuries in mines are complex and generally characterized by several factors starting from personal to technical and technical to social characteristics.In this paper,investigation was made through the application of structural equation modeling to study the nature of relationships between the influencing/associating personal factors and work injury and their sequential relationships leading towards work injury occurrences in underground coal mines.Six variables namely,rebelliousness,negative affectivity,job boredom,job dissatisfaction and work injury were considered in this study.Instruments were developed to quantify them through a questionnaire survey.Underground mine workers were randomly selected for the survey.Responses from 300 participants were used for the analysis.The structural model of LISREL was used to estimate the interrelationships amongst the variables.The case study results show that negative affectivity and job boredom induce more job dissatisfaction to the workers whereas risk taking attitude of the individual is positively influenced by job dissatisfaction as well as by rebelliousness characteristics of the individual.Finally,risk taking and job dissatisfaction are having positive significant direct relationship with work injury.The findings of this study clearly reveal that rebelliousness,negative affectivity and job boredom are the three key personal factors influencing work related injuries in mines that need to be addressed properly through effective safety programs. 展开更多
关键词 structural equation modeling Mine safety Occupational health and safety Work injury
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Experimental Insights on the Structural Patterns and Their Formation Mechanisms of the Xujiaweizi Fault Depression in the Songliao Basin 被引量:4
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作者 Wei Long Zhongquan Li +5 位作者 Ying Li Junliang Chen Fengyu Tan Zhiyi Zheng Jinmiao Hu Runfang Li 《Journal of Earth Science》 SCIE CAS CSCD 2018年第2期369-375,共7页
The Xujiaweizi (XJWZ) fault depression is a primary area for deep-seated gas explo- ration in Daqing. Through seismic profile interpretation, the main sag-controlling fault and struc- tural characteristics in the XJ... The Xujiaweizi (XJWZ) fault depression is a primary area for deep-seated gas explo- ration in Daqing. Through seismic profile interpretation, the main sag-controlling fault and struc- tural characteristics in the XJWZ fault depression were analyzed based on folds and faults analysis. A three-dimensional geological model of the XJWZ fault depression was also set up to enable fur- ther discussion by means of structural physical modeling. According to our research, the basic structural framework of the XJWZ fault depression was the result of regional extension. Its forma- tion and evolution were mainly controlled by the Xuxi fault. The structural framework of S-N blocking was due to changes in the fracture attitude. The Xuzhong uplift and the depressions on both sides belong to a normal-fault-related fold and were formed by controlling of the ramp/flat normal fault in the same tectonic movement period. 展开更多
关键词 structural physical modeling formation mechanism normal-fault-related fold Xujiaweizi fault depression.
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Different effects of economic and structural performance indexes on model construction of structural topology optimization 被引量:5
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作者 G.L.Yi Y.K.Sui 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第5期777-788,共12页
The objective and constraint functions related to structural optimization designs are classified into economic and performance indexes in this paper.The influences of their different roles in model construction of str... The objective and constraint functions related to structural optimization designs are classified into economic and performance indexes in this paper.The influences of their different roles in model construction of structural topology optimization are also discussed.Furthermore,two structural topology optimization models,optimizing a performance index under the limitation of an economic index,represented by the minimum compliance with a volume constraint(MCVC)model,and optimizing an economic index under the limitation of a performance index,represented by the minimum weight with a displacement constraint(MWDC)model,are presented.Based on a comparison of numerical example results,the conclusions can be summarized as follows:(1)under the same external loading and displacement performance conditions,the results of the MWDC model are almost equal to those of the MCVC model;(2)the MWDC model overcomes the difficulties and shortcomings of the MCVC model;this makes the MWDC model more feasible in model construction;(3)constructing a model of minimizing an economic index under the limitations of performance indexes is better at meeting the needs of practical engineering problems and completely satisfies safety and economic requirements in mechanical engineering,which have remained unchanged since the early days of mechanical engineering. 展开更多
关键词 Economic index Performance index structural topology optimization models MCVC model MWDC model Safety and economy
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Anomaly Models of Spatial Structures for Copper-Molybdenum Ore Deposits and their Application 被引量:11
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作者 MA Shengming ZHU Lixin +2 位作者 LIU Chongmin XI Mingjie TANG Shixin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第3期843-857,共15页
This paper discusses the enrichment and depletion regularities for porphyry coppermolybdenum ore deposits in different regions and varied deposit genetic types in the same area, taking three porphyry copper-molybdenum... This paper discusses the enrichment and depletion regularities for porphyry coppermolybdenum ore deposits in different regions and varied deposit genetic types in the same area, taking three porphyry copper-molybdenum ore deposits (i.e., the Chengmenshan in Jiangxi, Wunugetushan in Inner Mongolia, Baishantang in Gansu) and two copper deposits in Gansu Province (the Huitongshan skarn deposit and Gongpoquan composite deposit) as case studies. The results show that porphyry Cu-Mo deposits or skarn copper deposits include both enrichment of the ore-forming elements and associated elements, and depletion of some lithophile dispersed elements, rare earth elements (REE) and some major elements. And the depleted elements vary with deposits, having generality and their own features. On a deposit scale, the positive anomalies of enriched elements and negative anomalies of depleted elements follow in a sequence to comprise regular anomaly models of spatial structures. The exploration in the Tongchang deposit in Jiangxi and Huitongshan deposit in Gansu suggests that anomaly models play a key role in the identification of mineral occurrences and deposits compared to one single enriched element anomaly. And the anomaly models exert a critical effect on the optimization of prospecting targets and their potential evaluation. 展开更多
关键词 copper-molybdenum deposits enrichment and depletion anomaly models of spatial structures case studies
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Analysis of Ecosystem Degradation Factors in Yuanmou Arid-Hot Valleys Based on Interpretative Structural Model 被引量:2
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作者 ZHANG Bin LIU Gangcai +2 位作者 AI Nanshan SHI Kai SHU Chengqiang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第3期279-284,共6页
For ecological restoration and reconstruction of the degraded area, it is an important premise to correctly understand the degradation factors of the ecosystem in the arid-hot valleys. The factors including vegetation... For ecological restoration and reconstruction of the degraded area, it is an important premise to correctly understand the degradation factors of the ecosystem in the arid-hot valleys. The factors including vegetation degradation, land degradation, arid climate, policy failure, forest fire, rapid population growth, excessive deforestation, overgrazing, steep slope reclamation, economic poverty, engineering construction, lithology, slope, low cultural level, geological hazards, biological disaster, soil properties etc, were selected to study the Yuanmou arid-hot valleys. Based on the interpretative structural model (ISM), it has found out that the degradation factors of the Yuanmou arid-hot valleys were not at the same level but in a multilevel hierarchical system with internal relations, which pointed out that the degradation mode of the arid-hot valleys was "straight (appearance)-penetrating-background". Such researches have important directive significance for the restoration and reconstruction of the arid-hot valleys ecosystem. 展开更多
关键词 interpretative structural model ECOSYSTEM degradation factors the arid-hot valleys
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Nonaffine Network Structural Model for Molten Low-Density Polyethylene and High-Density Polyethylene in Oscillatory Shear 被引量:2
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作者 张娟 瞿金平 《Journal of Shanghai University(English Edition)》 CAS 2002年第4期292-296,共5页
We propose molten polymer's entanglement network deformation to be nonaffine and use transient network structural theory with the revised Liu's kinetics rate equation and the revised upper convected Maxwell co... We propose molten polymer's entanglement network deformation to be nonaffine and use transient network structural theory with the revised Liu's kinetics rate equation and the revised upper convected Maxwell constitutive equation to establish a nonaffine network structural constitutive model for studying the rheological behavior of molten Low Density Polyethylene (LDPE) and High Density Polyethylene (HDPE) in oscillatory shear. As a result, when the strain amplitude or frequency increases, the shear stress amplitude increases. At the same time, the accuracy of the nonaffine network model is higher than that of affine network model. It is clear that there is a small amount of nonaffine network deformation for LDPE melts which have long chain branches, and there is a larger amount of nonaffine network deformation in oscillatory shear for HDPE melts which has no long chain branches. So we had better consider the network deformation nonaffine when we establish the constitutive equations of polymer melts in oscillatory shear. 展开更多
关键词 kinetics rate equation nonaffine network structural model nonaffine deformation oscillatory shear.
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Systematic rationalization approach for multivariate correlated alarms based on interpretive structural modeling and Likert scale 被引量:5
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作者 高慧慧 徐圆 +2 位作者 顾祥柏 林晓勇 朱群雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1987-1996,共10页
Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalizati... Alarm flood is one of the main problems in the alarm systems of industrial process. Alarm root-cause analysis and alarm prioritization are good for alarm flood reduction. This paper proposes a systematic rationalization method for multivariate correlated alarms to realize the root cause analysis and alarm prioritization. An information fusion based interpretive structural model is constructed according to the data-driven partial correlation coefficient calculation and process knowledge modification. This hierarchical multi-layer model is helpful in abnormality propagation path identification and root-cause analysis. Revised Likert scale method is adopted to determine the alarm priority and reduce the blindness of alarm handling. As a case study, the Tennessee Eastman process is utilized to show the effectiveness and validity of proposed approach. Alarm system performance comparison shows that our rationalization methodology can reduce the alarm flood to some extent and improve the performance. 展开更多
关键词 Alarm rationalization Root-cause analysis Alarm priority Interpretive structural modeling Likert scale Tennessee Eastman process
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