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Improved concept models for straight thin-walled columns with box cross section 被引量:4
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作者 Yu-cheng LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第11期1473-1479,共7页
This paper focuses on developing improved concept models for straight thin-walled box sectional columns which can better predict the peak crushing force that occurs during crashworthiness analyses. We develop a nonlin... This paper focuses on developing improved concept models for straight thin-walled box sectional columns which can better predict the peak crushing force that occurs during crashworthiness analyses. We develop a nonlinear translational spring based on previous research and apply such a spring element to build the enhanced concept models. The work presented in this article is developed on the basis of the publication of the author (Liu and Day, 2006b) and has been applied in a crashworthiness design issue, which is presented by the author in another paper (Liu, 2008). 展开更多
关键词 concept model Peak crushing force Box section Nonlinear translational springs Crashworthiness analysis Thin-walled column
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ATMOSPHERIC BOUNDARY LAYER CONCEPT MODEL OF THE PEARL RIVER DELTA AND ITS APPLICATION 被引量:4
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作者 范绍佳 王安宇 +3 位作者 樊琦 刘吉 王宝民 塔纳 《Journal of Tropical Meteorology》 SCIE 2007年第1期8-13,共6页
Based on the geographical circumstance, climate and the boundary layer meteorology features of the Pearl River Delta, a boundary layer concept model of the Pearl River Delta was built. The concept model consists of fo... Based on the geographical circumstance, climate and the boundary layer meteorology features of the Pearl River Delta, a boundary layer concept model of the Pearl River Delta was built. The concept model consists of four fundamental factors that affect the boundary layer meteorology of the Pearl River Delta and can convincingly explain the reason of the air quality change in the Pearl River Delta. The model can be used to the diffusion capability analysis, the air pollution potential forecasting or haze forecasting, etc. 展开更多
关键词 boundary layer concept model Pearl River Delta
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Effects of health concept model-based detailed behavioral care on mood and quality of life in elderly patients with chronic heart failure
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作者 Ai-Di Zheng Li-Li Cai Jing Xu 《World Journal of Psychiatry》 SCIE 2023年第7期444-452,共9页
BACKGROUND With the intensification of social aging,the susceptibility of the elderly population to diseases has attracted increasing attention,especially chronic heart failure(CHF)that accounts for a large proportion... BACKGROUND With the intensification of social aging,the susceptibility of the elderly population to diseases has attracted increasing attention,especially chronic heart failure(CHF)that accounts for a large proportion of the elderly.AIM To evaluate the application value of health concept model-based detailed behavioral care in elderly patients with CHF.METHODS This study recruited 116 elderly CHF patients admitted from October 2018 to October 2020 and grouped them according to the nursing care that they received.The elderly patients who underwent health concept model-based detailed behavioral care were included in a study group(SG;n=62),and those who underwent routine detailed behavioral nursing intervention were included as a control group(CG;n=54).Patients’negative emotions(NEs),quality of life(QoL),and nutritional status were assessed using the self-rating anxiety/depression scale(SAS/SDS),the Minnesota Living with Heart Failure Questionnaire(MLHFQ),and the Modified Quantitative Subjective Global Assessment(MQSGA)of nutrition,respectively.Differences in rehabilitation efficiency,NEs,cardiac function(CF)indexes,nutritional status,QoL,and nursing satisfaction were comparatively analyzed.RESULTS A higher response rate was recorded in the SG vs the CG after intervention(P<0.05).After care,the left ventricular ejection fraction was higher while the left ventricular end-diastolic dimension and left ventricular end systolic diameter were lower in the SG compared with the CG(P<0.05).The post-intervention SAS and SDS scores,as well as MQSGA and MLHFQ scores,were also lower in the SG(P<0.05).The SG was also superior to the CG in the overall nursing satisfaction rate(P<0.05).CONCLUSION Health concept model-based detailed behavioral care has high application value in the nursing care of elderly CHF patients,and it can not only effectively enhance rehabilitation efficiency,but also mitigate patients’NEs and improve their CF and QoL. 展开更多
关键词 Chronic heart failure Elderly patients Health concept model Detailed behavioral care Patient mood Quality of life Nursing effect
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Concept Model of Ecological Civilization Regulated by Nature,Society and Government 被引量:1
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作者 GAN Jiang-ying1,WU Bin2 1.Nanchang Academy of Social Science,Nanchang 330038,China 2.Linchuan No.2 Middle School,Fuzhou 344100,China 《Asian Agricultural Research》 2011年第9期57-60,共4页
We studied theoretic development of ecological civilization,and put forward the concept model of ecological civilization regulated by nature,society and government.In the construction of ecological civilization,the na... We studied theoretic development of ecological civilization,and put forward the concept model of ecological civilization regulated by nature,society and government.In the construction of ecological civilization,the nature,society and government play different roles and have respective functions.Therefore,we should build a self-regulating network of ecological civilization through natural law,social law,as well as scientific outlook on development. 展开更多
关键词 ECOLOGICAL CIVILIZATION REGULATING network Scienti
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The Transform Method from the Concept Model to the Petri Net Model
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作者 蒋昌俊 《High Technology Letters》 EI CAS 1997年第1期42-45,共4页
A concept model for the specification of the system is presented in this paper. It includes power graph,resource graph and restriction set. The transformation algorithms from concept model to Petri net model are given... A concept model for the specification of the system is presented in this paper. It includes power graph,resource graph and restriction set. The transformation algorithms from concept model to Petri net model are given respectively. The method is illustrated by an example of the discrete manufacturing system. 展开更多
关键词 DISCRETE CONCURRENT system ESTABLISHMENT model PETRI NET concept model specification
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Concept modeling of tapered thin-walled tubes 被引量:1
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作者 Michael L.DAY 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第1期44-53,共10页
This paper presents a method to create concept models for the tapered thin-walled tubes using beam elements and spring elements.Developed concept tapered beam models with different taper angles and cross sections are ... This paper presents a method to create concept models for the tapered thin-walled tubes using beam elements and spring elements.Developed concept tapered beam models with different taper angles and cross sections are compared with those detailed models through impact analyses.Important crash results are recorded and compared,and the relatively good agreement is achieved between these analyses.Concept modeling steps are illustrated in detail,and a general concept modeling method for such thin-walled tubes is summarized and presented. 展开更多
关键词 Tapered tube concept model Axial crushing Impact analysis Beam element Spring element
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Optimized Modeling Method for Unbalanced Data in High-Level Visual Semantic Concept Classification
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作者 谭励 曹元大 +1 位作者 杨明华 贺巧艳 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期186-191,共6页
To solve the unbalanced data problems of learning models for semantic concepts, an optimized modeling method based on the posterior probability support vector machine (PPSVM) is presented. A neighborbased posterior ... To solve the unbalanced data problems of learning models for semantic concepts, an optimized modeling method based on the posterior probability support vector machine (PPSVM) is presented. A neighborbased posterior probability estimator for visual concepts is provided. The proposed method has been applied in a high-level visual semantic concept classification system and the experiment results show that it results in enhanced performance over the baseline SVM models, as well as in improved robustness with respect to high-level visual semantic concept classification. 展开更多
关键词 visual concept modeling posterior probability support vector machine unbalanced data
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Disturbed state concept as unified constitutive modeling approach 被引量:5
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作者 Chandrakant S.Desai 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2016年第3期277-293,共17页
A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeforma... A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeformations, stress path, volume change, microcracking leading to fracture, failure and softening,stiffening, and mechanical and environmental forces. There are hardly available such unified models. Thedisturbed state concept (DSC) is considered to be a unified approach and is able to provide materialcharacterization for almost all of the above factors. This paper presents a description of the DSC, andstatements for determination of parameters based on triaxial, multiaxial and interface tests. Statementsof DSC and validation at the specimen level and at the boundary value problem levels are also presented.An extensive list of publications by the author and others is provided at the end. The DSC is considered tobe a unique and versatile procedure for modeling behaviors of engineering materials and interfaces. 2016 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. This is an open access article under the CC BY-NC-ND license 展开更多
关键词 Disturbed state concept (DSC)Constitutive model Parameters Soils Interfaces Validations
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Hybrid Chinese Information Retrieval Model Based on the Combination of Keyword and Concept 被引量:2
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作者 樊孝忠 李宏乔 李良富 《Journal of Beijing Institute of Technology》 EI CAS 2003年第S1期120-123,共4页
A hybrid model that is based on the Combination of keywords and concept was put forward. The hybrid model is built on vector space model and probabilistic reasoning network. It not only can exert the advantages of key... A hybrid model that is based on the Combination of keywords and concept was put forward. The hybrid model is built on vector space model and probabilistic reasoning network. It not only can exert the advantages of keywords retrieval and concept retrieval but also can compensate for their shortcomings. Their parameters can be adjusted according to different usage in order to accept the best information retrieval result, and it has been proved by our experiments. 展开更多
关键词 hybrid information retrieval model concept retrieval vector space model probabilistic reasoning network
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Concept and evaluation of bay health:the role of numerical model in the Yueqing Bay,China
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作者 ZHOU Dacheng SUN Zhilin +2 位作者 HUANG Yu HUANG Saihua LI Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第8期3-15,共13页
To better evaluate the three-dimensional bay health and predict the dynamic bay health conditions, a concept of numerical bay health was introduced and a method of numerical bay health evaluation(NBHE) was developed... To better evaluate the three-dimensional bay health and predict the dynamic bay health conditions, a concept of numerical bay health was introduced and a method of numerical bay health evaluation(NBHE) was developed.To support the NBHE method, a numerical bay health index(NBHI) system was constructed, which assess the natural and socio-economic effects on the entire bay. Five index groups are combined to formulate the NBHI,including geometry, hydrodynamics and sediment dynamics, bio-ecology, water quality and socio-economy.Each group has different number of indices selected and weighted using AHP method according to their importance. Data were mainly synthesized from a variety of numerical models together with monitoring programs, which provide superior to other approaches in discriminating data integrity and predicting data in future. The NBHE method using NBHI system was applied in the Yueqing Bay during spring tide in April 2007.According to the NBHE results, Sta. A, at the surface level of the estuarine mouth, has a healthy geometry condition, sub-healthy hydrodynamic and sediment dynamic condition, and unhealthy water quality and bioecology conditions. The integrated healthy score at Sta. A indicates its sub-healthy condition. 展开更多
关键词 numerical bay health concept numerical model numerical index system three dimensional evaluation Yueqing Bay
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A VISCOPLASTIC MODEL BASED ON NO-YIELD-SURFACE CONCEPT
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作者 周光泉 程经毅 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第4期337-344,共8页
The elasticjviscoplastic constitutive equation which describes deformation law of metal materials was suggested based on no-yield-surface concept and thermal activation theory of dislocation. The equation which takes ... The elasticjviscoplastic constitutive equation which describes deformation law of metal materials was suggested based on no-yield-surface concept and thermal activation theory of dislocation. The equation which takes account of effects of strain-rate, strain history, strain-rate history, hardening and temperature has stronger physical basis.Comparison of the theoretical prediction with experimental results of mechanical behaviours of Ti under conditions of uniaxial stress and room temperature shows good consistency. 展开更多
关键词 A VISCOPLASTIC model BASED ON NO-YIELD-SURFACE concept
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Application of the Static Headland-Bay Beach Concept to a Sandy Beach: A New Elliptical Model
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作者 LI Bing ZHUANG Zhenye +1 位作者 CAO Lihua DU Fengchao 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第1期81-89,共9页
The headland-bay beach is one of the most common coastal types in the world.Its morphology reflects the changes that occurred during long-term evolution of the sandy coast.Several headland-bay beach models have been p... The headland-bay beach is one of the most common coastal types in the world.Its morphology reflects the changes that occurred during long-term evolution of the sandy coast.Several headland-bay beach models have been proposed to simulate the coastline’s configuration in equilibrium.In this paper,a new elliptical model is proposed,described,and applied.On the east coast of Laizhou Bay in Shandong Province from Longkou Port to Diaolongzui,four typical headland-bay beaches have developed,and four headland-bay beach models are used in this paper to simulate the morphology of these beaches to assess the applicability of each model.The simulation results of the elliptical model verify that it is applicable to the study area.In addition,the elliptical model is easy to use.Through simulation and field investigations,we concluded that most of the coastal segments in this area will remain in an erosion state,and the human activity has a significant impact on the shoreline’s evolution. 展开更多
关键词 static headland-bay beach concept elliptical model sandy beach coastal erosion east coast of Laizhou Bay
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基于24Model的煤炭企业安全文化提升实践研究 被引量:1
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作者 崔义 刘振宇 +6 位作者 闫寿庆 王冰山 秦东立 姜琦 郭洁 张磊 赵金坤 《煤矿安全》 CAS 北大核心 2024年第2期250-256,共7页
为了发挥安全文化在事故预防中的重要作用,运用基于事故致因“2-4”模型的安全文化水平提升方法研究某煤炭企业的安全文化建设现状并提出改进措施。首先,明确了24Model视域下的安全文化水平提升方法在我国的适用性;然后,从安全文化水平... 为了发挥安全文化在事故预防中的重要作用,运用基于事故致因“2-4”模型的安全文化水平提升方法研究某煤炭企业的安全文化建设现状并提出改进措施。首先,明确了24Model视域下的安全文化水平提升方法在我国的适用性;然后,从安全文化水平现状和安全理念2方面开展了针对该企业的实践研究;最后,提出改进措施。结果表明:该企业安全文化水平总体上要比国内或同行业的安全业绩较差的企业好,比安全业绩较好的企业差;该企业安全理念涉及32元素的13个方面;一线人员、班组长、专业人员和领导层对部分元素的理解程度不佳,并且这些元素中仅有元素3、元素4、元素6、元素13、元素16的内容在企业的安全理念有所体现。提出了14条改进的安全理念用于提高企业的安全文化水平。 展开更多
关键词 安全文化 事故致因“2-4”模型 安全理念 事故预防 安全制度 安全认知
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Numerical Simulation of Oxy-coal Combustion for a Swirl Burner with EDC Model 被引量:6
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作者 崔凯 刘冰 +3 位作者 吴玉新 杨海瑞 吕俊复 张海 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第2期193-201,共9页
The characteristics of oxy-coal combustion for a swirl burner with a specially designed preheating chamber are studied numerically. In order to increase the accuracy in the prediction of flame temperature and igni- ti... The characteristics of oxy-coal combustion for a swirl burner with a specially designed preheating chamber are studied numerically. In order to increase the accuracy in the prediction of flame temperature and igni- tion position, eddy dissipation concept (EDC) model with a skeletal chemical reaction mechanism was adopted to describe the combustion of volatile matter. Simulation was conducted under six oxidant stream conditions with dif- ferent OjN2/CO2 molar ratios: 21/79/0, 30/70/0, 50/50/0, 21/0/79, 30/0/70 and 50/0/50. Results showed that 02 en- richment in the primary oxidant stream is in favor of combustion stabilization, acceleration of ignition and increase of maximum flame temperature, while the full substitution of N2 by CO2 in the oxidant stream delays ignition and decreases the maximum flame temperature. However, the overall flow field and flame shapes in these cases are very similar at the same flow rate of the primary oxidant stream. Combustion characteristics of the air-coal is similar to that of the oxy-coal with 30% 02 and 70% CO2 in the oxidant stream, indicating that the rear condition is suitable for retrofitting an air-coal fired boiler to an oxy-coal one. The swirl burner with a specially designed preheating chamber can increase flame temperature, accelerate ignition and enhance burning intensity of pulverized coal under oxy-coal combustion. Also, qualitative experimental validation indicated the burner can reduce the overall NOx emission under certain 02 enrichment and oxy-coal combustion conditions against the air-coal combustion. 展开更多
关键词 oxy-coal eddy dissipation concept model COAL swirl burner
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The research on the remote sensing's information tree model of the Nansha coral islets and reef's spatial structure 被引量:1
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作者 Liu Baoyin Wang Yanfeng and Hao Qingxiang(First institute of beanography, State  ̄ic Administration, Qingdso 266003, China Naming University, Naming 210008, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1996年第3期331-344,共14页
Based on the Nansha coral islets and reef's time-space attributes,and the intension and extension of the remote sensing information, the concept model and concept system of coral islets and reef are proposed.Then ... Based on the Nansha coral islets and reef's time-space attributes,and the intension and extension of the remote sensing information, the concept model and concept system of coral islets and reef are proposed.Then twin-tree remote sensing information model for different kinds of reef is constructed by using abstracted islets and reef's primitive, and the structure recognition system for coral islets and reef type is developed. 展开更多
关键词 Nansha Islands coral reefs remote sensing information tree concept model PRIMITIVE
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基于Concept-Relation模型的军事文本知识获取
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作者 雷玉霞 曹宝香 《曲阜师范大学学报(自然科学版)》 CAS 2004年第1期46-49,共4页
介绍一种从《中国大百科全书》文本中获取军事知识的方法 .该方法由 2部分组成 :第一部分是军事知识描述语言 (MKDL) ,由知识工程师用于将文本知识翻译成基于Concept_Relation_模型的MKDL形式化文本知识 ;第二部分是MKDL编译系统 .该系... 介绍一种从《中国大百科全书》文本中获取军事知识的方法 .该方法由 2部分组成 :第一部分是军事知识描述语言 (MKDL) ,由知识工程师用于将文本知识翻译成基于Concept_Relation_模型的MKDL形式化文本知识 ;第二部分是MKDL编译系统 .该系统通过对MKDL文本的编译、分析和知识连接而最后生成军事知识库 . 展开更多
关键词 concept-Relation模型 军事文本 知识获取 军事知识描述语言 MKDL编译系统
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基于“The all-on-3 concept”以不同角度植入远中倾斜种植体的种植固定全口义齿修复模型各部件应力峰值 被引量:2
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作者 杨凯文 刘艾芃 +4 位作者 赵娅琴 谭桂莲 李鸿宇 王注力 邓文正 《山东医药》 CAS 2022年第3期35-38,共4页
目的分析不同植入角度“The all-on-3 concept”远中倾斜种植体两种加载条件下模型各部件的应力分布。方法建立种植固定全口义齿修复模型,其中“The all-on-3 concept”模型3组(分别记为3-17°、3-30°、3-45°组)及“All-o... 目的分析不同植入角度“The all-on-3 concept”远中倾斜种植体两种加载条件下模型各部件的应力分布。方法建立种植固定全口义齿修复模型,其中“The all-on-3 concept”模型3组(分别记为3-17°、3-30°、3-45°组)及“All-on-4”模型1组(4-30°组),3-17°组、3-30°组、3-45°组、4-30°组种植体数量分别为3、3、3、4颗,远中倾斜种植体植入角度分别为17°、30°、45°、30°,修复体远中悬臂长度为14.7、12.8、9.6、12.8 mm,近中种植体与远中种植体间距分别为15.3、17.2、20.9、6.8 mm,使用有限元软件对4组模型进行垂直以及倾斜加载,分析两种加载模式下各组模型各部件(下颌骨、种植体、基台、修复螺丝、氧化锆桥)的应力峰值。结果在两种加载模式下,3-45°组各部件最大应力峰值出现次数最多、应力分布最不均匀,其次为3-17°组和3-30°组,4-30°组在对比中未出现最大应力峰值。结论“The all-on-3 concept”远中种植体植入角度为30°时各部件应力分布情况最佳,其次为17°,最差为45°,但“The all-on-3 concept”应力分布情况略差于“All-on-4”。 展开更多
关键词 种植固定全口义齿 “The all-on-3 concept”模型 “All-on-4”模型 种植体 应力峰值
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A Brief Analysis of the Self-correction Model——from the View of Linking Theory
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作者 佘阿莉 《教师》 2017年第32期78-79,共2页
Based on the theory of the post method pedagogy and the teaching practice,this paper proposes a new teaching model,the self-correction model,and explains it from the point of view of linking theory.
关键词 SELF-CORRECTION model LINKING THEORY concept IMPLICATIONS
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Review of permeability evolution model for fractured porous media 被引量:5
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作者 Jianjun Ma 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第3期351-357,共7页
The ability to capture permeability of fractured porous media plays a significant role in several engineering applications, including reservoir, mining, petroleum and geotechnical engineering. In order to solve fluid ... The ability to capture permeability of fractured porous media plays a significant role in several engineering applications, including reservoir, mining, petroleum and geotechnical engineering. In order to solve fluid flow and coupled flow-deformation problems encountered in these engineering applications,both empirical and theoretical models had been proposed in the past few decades. Some of them are simple but still work in certain circumstances; others are complex but also need some modifications to be applicable. Thus, the understanding of state-of-the-art permeability evolution model would help researchers and engineers solve engineering problems through an appropriate approach. This paper summarizes permeability evolution models proposed by earlier and recent researchers with emphasis on their characteristics and limitations. 展开更多
关键词 Permeability Fractured porous media Porosity Damage Network model Equivalent channel concept
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Establishment and Validation for the Theoretical Model of the Vehicle Airbag 被引量:2
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作者 ZHANG Junyuan JIN Yang +1 位作者 XIE Lizhe CHEN Chao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期487-495,共9页
The current design and optimization of the occupant restraint system(ORS) are based on numerous actual tests and mathematic simulations. These two methods are overly time-consuming and complex for the concept design... The current design and optimization of the occupant restraint system(ORS) are based on numerous actual tests and mathematic simulations. These two methods are overly time-consuming and complex for the concept design phase of the ORS, though they're quite effective and accurate. Therefore, a fast and directive method of the design and optimization is needed in the concept design phase of the ORS. Since the airbag system is a crucial part of the ORS, in this paper, a theoretical model for the vehicle airbag is established in order to clarify the interaction between occupants and airbags, and further a fast design and optimization method of airbags in the concept design phase is made based on the proposed theoretical model. First, the theoretical expression of the simplified mechanical relationship between the airbag's design parameters and the occupant response is developed based on classical mechanics, then the momentum theorem and the ideal gas state equation are adopted to illustrate the relationship between airbag's design parameters and occupant response. By using MATLAB software, the iterative algorithm method and discrete variables are applied to the solution of the proposed theoretical model with a random input in a certain scope. And validations by MADYMO software prove the validity and accuracy of this theoretical model in two principal design parameters, the inflated gas mass and vent diameter, within a regular range. This research contributes to a deeper comprehension of the relation between occupants and airbags, further a fast design and optimization method for airbags' principal parameters in the concept design phase, and provides the range of the airbag's initial design parameters for the subsequent CAE simulations and actual tests. 展开更多
关键词 occupant restraint systems AIRBAG theoretical model concept design
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