期刊文献+
共找到3,080篇文章
< 1 2 154 >
每页显示 20 50 100
Associations of genome-wide structural variations with phenotypic differences in cross-bred Eurasian pigs 被引量:1
1
作者 Wencheng Zong Jinbu Wang +8 位作者 Runze Zhao Naiqi Niu Yanfang Su Ziping Hu Xin Liu Xinhua Hou Ligang Wang Lixian Wang Longchao Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期68-87,共20页
Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability ... Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability to adapt to the local environment.SVs(≥50 bp)are widely distributed in the genome,mainly in the form of insertion(INS),mobile element insertion(MEI),deletion(DEL),duplication(DUP),inversion(INV),and translocation(TRA).While studies have investigated the SVs in pig genomes,genome-wide association studies(GWAS)-based on SVs have been rarely conducted.Results Here,we obtained a high-quality SV map containing 123,151 SVs from 15 Large White and 15 Min pigs through integrating the power of several SV tools,with 53.95%of the SVs being reported for the first time.These high-quality SVs were used to recover the population genetic structure,confirming the accuracy of genotyping.Potential functional SV loci were then identified based on positional effects and breed stratification.Finally,GWAS were performed for 36 traits by genotyping the screened potential causal loci in the F2 population according to their corresponding genomic positions.We identified a large number of loci involved in 8 carcass traits and 6 skeletal traits on chromosome 7,with FKBP5 containing the most significant SV locus for almost all traits.In addition,we found several significant loci in intramuscular fat,abdominal circumference,heart weight,and liver weight,etc.Conclusions We constructed a high-quality SV map using high-coverage sequencing data and then analyzed them by performing GWAS for 25 carcass traits,7 skeletal traits,and 4 meat quality traits to determine that SVs may affect body size between European and Chinese pig breeds. 展开更多
关键词 Body size GWAS PIG SKELETON structural variations
下载PDF
Evaluation on Spot Weld Models in Structural Dynamic Analysis of Automotive Body in White 被引量:9
2
作者 LIANG Jianyong LIANG Jun FANG Guodong PAN Zimin LI Wei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第1期84-90,共7页
Spot weld models are widely used in finite element analysis(FEA) of automotive body in white(BIW) to predict static,dynamic,durability and other characteristics of automotive BIW.However,few researches are done on... Spot weld models are widely used in finite element analysis(FEA) of automotive body in white(BIW) to predict static,dynamic,durability and other characteristics of automotive BIW.However,few researches are done on evaluation of the validity of these spot weld models in structural dynamic analysis of BIW.To evaluate the validity and accuracy of spot weld models in structural dynamic analysis of BIW,two object functions,error function and deviation function,are introduced innovatively.Modal analysis of Two-panel and Double-hat structures,which are the dominated structures in BIW,is conducted,and the values of these two object functions are obtained.Based on the values of object functions,the validity of these spot weld models are evaluated.It is found that the area contact method(ACM2) and weld element connection(CWELD) can give more precise prediction in modal analysis of these two classical structures,thus are more applicable to structural dynamic analysis of automotive BIW.Modal analysis of a classical BIW is performed,which further confirms this evaluation.The error function and deviation function proposed in this research can give guidance on the adaptability of spot weld models in structural dynamic analysis of BIW.And this evaluation method can also be adopted in evaluation of other finite element models in static,dynamic and other kinds of analysis for automotive structures. 展开更多
关键词 spot weld model structural dynamic analysis modal analysis two-panel structure double-hat structure body in white
下载PDF
Interpretation of residual gravity anomaly caused by simple shaped bodies using very fast simulated annealing global optimization 被引量:3
3
作者 Arkoprovo Biswas 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第6期875-893,共19页
A very fast simulated annealing(VFSA) global optimization is used to interpret residual gravity anomaly.Since,VFSA optimization yields a large number of best-fitted models in a vast model space;the nature of uncerta... A very fast simulated annealing(VFSA) global optimization is used to interpret residual gravity anomaly.Since,VFSA optimization yields a large number of best-fitted models in a vast model space;the nature of uncertainty in the interpretation is also examined simultaneously in the present study.The results of VFSA optimization reveal that various parameters show a number of equivalent solutions when shape of the target body is not known and shape factor 'q' is also optimized together with other model parameters.The study reveals that amplitude coefficient k is strongly dependent on shape factor.This shows that there is a multi-model type uncertainty between these two model parameters derived from the analysis of cross-plots.However,the appraised values of shape factor from various VFSA runs clearly indicate whether the subsurface structure is sphere,horizontal or vertical cylinder type structure.Accordingly,the exact shape factor(1.5 for sphere,1.0 for horizontal cylinder and 0.5 for vertical cylinder)is fixed and optimization process is repeated.After fixing the shape factor,analysis of uncertainty and cross-plots shows a well-defined uni-model characteristic.The mean model computed after fixing the shape factor gives the utmost consistent results.Inversion of noise-free and noisy synthetic data as well as field data demonstrates the efficacy of the approach. 展开更多
关键词 Gravity anomaly Idealized body Uncertainty VFSA Subsurface structure Ore exploration
下载PDF
A strategy for lightweight designing of a railway vehicle car body including composite material and dynamic structural optimization 被引量:2
4
作者 Alessio Cascino Enrico Meli Andrea Rindi 《Railway Engineering Science》 2023年第4期340-350,共11页
Rolling stock manufacturers are finding structural solutions to reduce power required by the vehicles,and the lightweight design of the car body represents a possible solution.Optimization processes and innovative mat... Rolling stock manufacturers are finding structural solutions to reduce power required by the vehicles,and the lightweight design of the car body represents a possible solution.Optimization processes and innovative materials can be combined in order to achieve this goal.In this framework,we propose the redesign and optimization process of the car body roof for a light rail vehicle,introducing a sandwich structure.Bonded joint was used as a fastening system.The project was carried out on a single car of a modern tram platform.This preliminary numerical work was developed in two main steps:redesign of the car body structure and optimization of the innovated system.Objective of the process was the mass reduction of the whole metallic structure,while the constraint condition was imposed on the first frequency of vibration of the system.The effect of introducing a sandwich panel within the roof assembly was evaluated,focusing on the mechanical and dynamic performances of the whole car body.A mass saving of 63%on the optimized components was achieved,corresponding to a 7.6%if compared to the complete car body shell.In addition,a positive increasing of 17.7%on the first frequency of vibration was observed.Encouraging results have been achieved in terms of weight reduction and mechanical behaviour of the innovated car body. 展开更多
关键词 structural dynamic optimization Car body lightweight design Railway vehicle dynamics Railway car body engineering Railway vehicle design Composite materials
下载PDF
Geological characteristics and models of fault-foldfracture body in deep tight sandstone of the second member of Upper Triassic Xujiahe Formation in Xinchang structural belt of Sichuan Basin,SW China 被引量:1
5
作者 LIU Junlong LIU Zhongqun +8 位作者 LIU Zhenfeng LIU Yali SHEN Baojian XIAO Kaihua BI Youyi WANG Xiaowen WANG Ail FAN Lingxiao LI Jitongl 《Petroleum Exploration and Development》 SCIE 2023年第3期603-614,共12页
In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot... In the second member of the Upper Triassic Xujiahe Formation(T_(3)x_(2))in the Xinchang area,western Sichuan Basin,only a low percent of reserves has been recovered,and the geological model of gas reservoir sweet spot remains unclear.Based on a large number of core,field outcrop,test and logging-seismic data,the T_(3)x_(2) gas reservoir in the Xinchang area is examined.The concept of fault-fold-fracture body(FFFB)is proposed,and its types are recognized.The main factors controlling fracture development are identified,and the geological models of FFFB are established.FFFB refers to faults,folds and associated fractures reservoirs.According to the characteristics and genesis,FFFBs can be divided into three types:fault-fracture body,fold-fracture body,and fault-fold body.In the hanging wall of the fault,the closer to the fault,the more developed the effective fractures;the greater the fold amplitude and the closer to the fold hinge plane,the more developed the effective fractures.Two types of geological models of FFFB are established:fault-fold fracture,and matrix storage and permeability.The former can be divided into two subtypes:network fracture,and single structural fracture,and the later can be divided into three subtypes:bedding fracture,low permeability pore,and extremely low permeability pore.The process for evaluating favorable FFFB zones was formed to define favorable development targets and support the well deployment for purpose of high production.The study results provide a reference for the exploration and development of deep tight sandstone oil and gas reservoirs in China. 展开更多
关键词 fault-fold-fracture body fracture control factor genetic characteristics geological model deep layer tight sandstone Xinchang structural belt Upper Triassic Xujiahe Formation Sichuan Basin
下载PDF
COMPUTER SYSTEM FOR GEOMETRIC MODELING OF GEOLOGIC BODIES AND APPLICATIONS
6
作者 Dai, Tagen Mao, Xiancheng 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第4期179-184,共6页
INTRODUCTIONThemodelsofgeometricmodelingofgeologicbodiesbeargeometric,topologicalandattributeinformation[1... INTRODUCTIONThemodelsofgeometricmodelingofgeologicbodiesbeargeometric,topologicalandattributeinformation[1].Bymeansofcomput... 展开更多
关键词 GEOLOGIC BODY data structure MATHEMATICAL model automatic PLOTTING
下载PDF
Structural Traits,Structural Indices and Body Weight Prediction of Arsi Cows
7
作者 Aman Gudeto Tesfaye Alemu Aredo +1 位作者 Tadele Mirkena Sandip Banerjee 《NASS Journal of Agricultural Sciences》 2022年第1期33-40,共8页
Structural measurements are indicators of animal performance,productivity and carcass characteristics.This study was conducted with the objectives of assessing structural measurements,developing body weight prediction... Structural measurements are indicators of animal performance,productivity and carcass characteristics.This study was conducted with the objectives of assessing structural measurements,developing body weight prediction and structural indices for cows of Arsi breed.The cows were purchased from highland and lowland agro-ecologies of Arsi and East Shoa zones of Oromia regional state,Ethiopia and kept in Adami Tulu Agricultural Research Center(ATARC)for the breed development purpose.Totally 222 cows were included in the structural traits measurement.Thirty four young heifers were also considered in the study.Twenty two structural traits were considered during observational survey.The structural index was calculated from the phenotypically correlated linear measurements.Structural traits were analyzed by T-test of SPSS version twenty four.The observed average values of height at wither,chest depth,heart girth,body length,pelvic width,cannon bone circumferences of the cows were 107,55.62,141.06,117.82,31.41 and 13.58cm,respectively.Heart girth(0.82),flank girth(0.73),hook circumferences(0.67),chest depth(0.65)and height at rump(0.64)were highly correlated(P<0.01)to body weight of the cows.Regression analysis indicated that hearth girth had the highest coefficient of determination for body weight of the cows and heifers.Accordingly,the simple linear equations were developed to predict the body weight of cows and heifers.Body weight of Arsi cow(y)=-221.005+3.1(heart girth)and Body weight of Arsi heifer(y)=-188.452+2.75(heart girth).Based on this,the measuring chart tape can be developed to estimate the body weight of Arsi cows and heifers at field condition where there is no access to weighing scales. 展开更多
关键词 Cattle structural traits Arsi cows structural indices Body weight prediction
下载PDF
3D near-surface P-wave velocity structure imaging with Distributed Acoustic Sensing and electric hammer source
8
作者 Heting Hong Fu Yin +2 位作者 Yuhang Lei Yulan Li Baoshan Wang 《Earthquake Research Advances》 CSCD 2024年第3期27-33,共7页
Distributed Acoustic Sensing(DAS) is an emerging technique for ultra-dense seismic observation, which provides a new method for high-resolution sub-surface seismic imaging. Recently a large number of linear DAS arrays... Distributed Acoustic Sensing(DAS) is an emerging technique for ultra-dense seismic observation, which provides a new method for high-resolution sub-surface seismic imaging. Recently a large number of linear DAS arrays have been used for two-dimensional S-wave near-surface imaging in urban areas. In order to explore the feasibility of three-dimensional(3D) structure imaging using a DAS array, we carried out an active source experiment at the Beijing National Earth Observatory. We deployed a 1 km optical cable in a rectangular shape, and the optical cable was recast into 250 sensors with a channel spacing of 4 m. The DAS array clearly recorded the P, S and surface waves generated by a hammer source. The first-arrival P wave travel times were first picked with a ShortTerm Average/Long-Term Average(STA/LTA) method and further manually checked. The P-wave signals recorded by the DAS are consistent with those recorded by the horizontal components of short-period seismometers. At shorter source-receiver distances, the picked P-wave arrivals from the DAS recording are consistent with vertical component recordings of seismometers, but they clearly lag behind the latter at greater distances.This is likely due to a combination of the signal-to-noise ratio and the polarization of the incoming wave. Then,we used the Tomo DD software to invert the 3D P-wave velocity structure for the uppermost 50 m with a resolution of 10 m. The inverted P-wave velocity structures agree well with the S-wave velocity structure previously obtained through ambient noise tomography. Our study indicates the feasibility of 3D near-surface imaging with the active source and DAS array. However, the inverted absolute velocity values at large depths may be biased due to potential time shifts between the DAS recording and seismometer at large source-receiver distances. 展开更多
关键词 Distributed Acoustic Sensing(DAS) Near-surface structure First-arrival travel time tomography Body wave Active source
下载PDF
中低温岩浆热液型金矿床找矿预测地质模型
9
作者 薛建玲 庞振山 +5 位作者 程志中 陈辉 张晓飞 贾儒雅 俞炳 牟妮妮 《岩石学报》 SCIE EI CAS 北大核心 2025年第1期4-30,共27页
我国金矿资源对外依存度长期居高不下,立足国内,寻找并探明一批大型金矿床是一项迫在眉睫的重大任务。中低温岩浆热液型金矿床是我国金的最主要来源,如何寻找其隐伏矿和深部矿成为当前矿产勘查研究的热点。本文以勘查区找矿预测理论为指... 我国金矿资源对外依存度长期居高不下,立足国内,寻找并探明一批大型金矿床是一项迫在眉睫的重大任务。中低温岩浆热液型金矿床是我国金的最主要来源,如何寻找其隐伏矿和深部矿成为当前矿产勘查研究的热点。本文以勘查区找矿预测理论为指导,以中低温岩浆热液型金矿床为研究对象,总结了中低温岩浆热液型金矿床地质特征,构建了以成矿地质体、成矿构造和成矿结构面特征和成矿作用特征标志为核心内容的找矿预测地质模型,为该类型金矿床找矿预测提供了新的思路,指导隐伏矿和深部矿金资源勘查取得突破。中低温岩浆热液型金矿床分为中温岩浆热液型金矿床和低温岩浆热液型金矿床两个亚类,广泛发育于陆块区和造山带中,赋矿围岩多种多样,成矿时代广泛,主要集中在中生代。本文厘定了中低温岩浆热液型金矿床成矿地质体为中酸性侵入体,与矿床(体)呈现出空间上相依(1~5km)、时间上相近(10Myr)、成因上相关的内在成生联系和时空配置关系。成矿构造属褶皱、断裂、岩浆侵入复合构造系统;成矿结构面主要有断裂、硅钙面、岩溶构造及岩体侵入接触带、爆破角砾岩体及水压裂隙等;矿化样式受成矿结构面控制,大致可分为四个类型:层状、脉状、块状及其组合而成的复合型。中温岩浆热液型金矿床成矿作用早阶段温度可达450℃左右,形成强度不等的钾长石化、钠长石化或铁白云石化;主成矿阶段成矿温度250℃左右,蚀变主要为硅化、绢云母化、伊利石化,Au和Ag共伴生,同时伴生少量Pb、Zn、Cu等,主要金属矿物为黄铁矿,次为黄铜矿、磁黄铁矿、方铅矿和闪锌矿;而低温岩浆热液型金矿床成矿作用主阶段温度低于250℃,Au和As、Sb共伴生,Ag含量低,常见毒砂和辉锑矿等矿物,成矿作用早阶段蚀变则主要为硅化,有的为次生石英岩化。金的沉淀富集机制包括流体的沸腾、混合和交代等机制。成矿作用中心位于岩体外接触带2~3km和接触带之内,由浅部到深部形成“上脉下层”的二元结构模式,脉状矿体具有侧伏延深规律,在此基础上构建了找矿预测地质模型。在该模型指导下,我们重新厘定了我国重要成矿区带金矿床类型,在深部发现新的矿体样式,拓宽了深部找矿空间,提升了我国重要成矿区带成矿规律的认识水平,带动了我国重要成矿区带金矿找矿新突破。 展开更多
关键词 中温岩浆热液型金矿床 低温岩浆热液型金矿床 成矿地质体 成矿构造与成矿结构面 成矿作用特征标志 找矿预测模型
下载PDF
地震体波走时与重力快速联合反演方法研究
10
作者 谭智 石磊 李永华 《地球物理学报》 北大核心 2025年第1期111-122,共12页
多种地球物理资料联合反演是克服反演多解性的有效手段.本文发展了一种近震体波走时与重力快速联合成像方法.该方法基于兼顾浅部和深部介质速度与密度的混合关系,将频率域拟三维重力正演与双差层析成像方法相结合,构建三维壳幔速度模型... 多种地球物理资料联合反演是克服反演多解性的有效手段.本文发展了一种近震体波走时与重力快速联合成像方法.该方法基于兼顾浅部和深部介质速度与密度的混合关系,将频率域拟三维重力正演与双差层析成像方法相结合,构建三维壳幔速度模型.基于两个不同模型的理论测试表明,该联合反演算法不仅能很好的恢复模型特征,还提高了计算效率.进一步将该方法应用于青藏高原东北缘地壳上地幔P波速度结构构建,反演结果与地表地质构造、深地震测深结果相吻合,验证了本文反演算法在实际数据应用中的可靠性和有效性. 展开更多
关键词 重力正演 频率域 近震体波 联合反演 速度结构
下载PDF
单原子Pt负载在锐钛矿(001)表面的电光学特性研究
11
作者 靳帆 赵志超 《原子与分子物理学报》 CAS 北大核心 2025年第6期43-50,共8页
基于第一性原理的多体格林函数理论方法,系统探究了锐钛矿TiO_(2)(001)表面负载Pt单原子催化剂的电子结构和光学性质,考虑Pt在完美表面和缺陷表面(O空位)两种基底上的负载.结果发现,Pt会在TiO_(2)禁带中间、价带和导带边缘引入新能级,... 基于第一性原理的多体格林函数理论方法,系统探究了锐钛矿TiO_(2)(001)表面负载Pt单原子催化剂的电子结构和光学性质,考虑Pt在完美表面和缺陷表面(O空位)两种基底上的负载.结果发现,Pt会在TiO_(2)禁带中间、价带和导带边缘引入新能级,但不同基底负载的Pt单原子催化剂存在不同的带隙特性.Pt的负载会引起体系光学吸收红移,增大光学吸收范围,延伸光吸收至可见光甚至是红外区域,提升可见光活化的可能性,同时改善体系的激子束缚能,有利于空穴与电子有效分离,这可能是Pt负载后光催化性能提升的原因之一.然而,若在可见光或低能量紫外光激发后,分离的电子与空穴没有及时参与反应,体系衰变回最低激发态,此时极大的激子束缚能可能会加速电子与空穴重组,不利于表面催化反应的进行.负载在O空位的催化剂最低激发态的激子束缚能比完美表面小,重组速率慢.计算结果能够为理解单原子催化剂结构-性能关系提供一些见解. 展开更多
关键词 二氧化钛 Pt单原子催化剂 多体格林函数理论 电子结构 光吸收
下载PDF
欧洲多源制调车机车车体平台技术研究
12
作者 曹媛 金希红 +1 位作者 陆军 黎宏飞 《电力机车与城轨车辆》 2025年第1期30-34,共5页
为应对欧洲调车机车市场的需求,同时降低后续车型研发和认证的周期及成本,文章提出了一种多源制调车机车车体平台。首先,通过底架结构设计、车体接口平台化设计及车体轻量化设计,实现不同能源制式下设备的安装需求,以及在重量分配和安... 为应对欧洲调车机车市场的需求,同时降低后续车型研发和认证的周期及成本,文章提出了一种多源制调车机车车体平台。首先,通过底架结构设计、车体接口平台化设计及车体轻量化设计,实现不同能源制式下设备的安装需求,以及在重量分配和安装空间方面预留出后续平台车型变化的空间;其次,对平台化车体结构强度进行安全性评估,确保车体结构可以满足所有平台车型及后续配置变化时的承载要求;最后,对车体安装组件进行模块化设计,实现该平台下不同车型的快速转换。 展开更多
关键词 车体 结构 平台 调车机车
下载PDF
动力集中动车组动力车车体结构与强度设计
13
作者 单勇 《电力机车与城轨车辆》 2025年第1期55-60,共6页
动力集中动车组动力车的车体结构是各种设备的关键载体,以及整列车牵引力和制动力的重要传递部件。针对相关标准及用户对动力集中动车组动力车车体结构与强度的要求,文章分析了动力集中动车组的运行环境和载荷特点,针对关键载荷特点提... 动力集中动车组动力车的车体结构是各种设备的关键载体,以及整列车牵引力和制动力的重要传递部件。针对相关标准及用户对动力集中动车组动力车车体结构与强度的要求,文章分析了动力集中动车组的运行环境和载荷特点,针对关键载荷特点提出适应性的车体结构方案,并通过仿真及试验等手段验证该方案的可行性和有效性。文章提出了气动载荷对车体结构的影响、车体模态对整车抗蛇行运动的影响、局部振动的影响,以及车体结构自身稳定性等问题,并提供了相关解决方法。 展开更多
关键词 动力集中动车组 动力车 车体结构 强度设计 模态
下载PDF
瞬变电磁技术对地质构造富(导)水性的探测研究
14
作者 韩霞 《煤》 2025年第1期96-99,共4页
利用瞬变电磁勘探方法,通过视电阻率反演技术,分析目标体和目的层位的电性变化特征,寻找视电阻率低阻区以及其变化情况。分析目标体在层面和层间的富水性特征,即预测预报其富(导)水性,从而以此为基础制定合理科学的防治水技术方案,确保... 利用瞬变电磁勘探方法,通过视电阻率反演技术,分析目标体和目的层位的电性变化特征,寻找视电阻率低阻区以及其变化情况。分析目标体在层面和层间的富水性特征,即预测预报其富(导)水性,从而以此为基础制定合理科学的防治水技术方案,确保煤矿防治水安全。 展开更多
关键词 瞬变电磁技术 视电阻率反演 地质构造 目标体 富(导)水性
下载PDF
Design of lightweight magnesium car body structure under crash and vibration constraints 被引量:25
15
作者 Morteza Kiani Imtiaz Gandikota +1 位作者 Masoud Rais-Rohani Keiichi Motoyama 《Journal of Magnesium and Alloys》 SCIE EI CAS 2014年第2期99-108,共10页
Car body design in view of structural performance and lightweighting is a challenging task due to all the performance targets that must be satisfied such as vehicle safety and ride quality.In this paper,material repla... Car body design in view of structural performance and lightweighting is a challenging task due to all the performance targets that must be satisfied such as vehicle safety and ride quality.In this paper,material replacement along with multidisciplinary design optimization strategy is proposed to develop a lightweight car body structure that satisfies the crash and vibration criteria while minimizing weight.Through finite element simulations,full frontal,offset frontal,and side crashes of a full car model are evaluated for peak acceleration,intrusion distance,and the internal energy absorbed by the structural parts.In addition,the first three fundamental natural frequencies are combined with the crash metrics to form the design constraints.The wall thicknesses of twenty-two parts are considered as the design variables.Latin Hypercube Sampling is used to sample the design space,while Radial Basis Function methodology is used to develop surrogate models for the selected crash responses at multiple sites as well as the first three fundamental natural frequencies.A nonlinear surrogate-based optimization problem is formulated for mass minimization under crash and vibration constraints.Using Sequential Quadratic Programming,the design optimization problem is solved with the results verified by finite element simulations.The performance of the optimum design with magnesium parts shows significant weight reduction and better performance compared to the baseline design. 展开更多
关键词 Multidisciplinary design optimization Magnesium structure Car body structure CRASHWORTHINESS VIBRATION Vehicle design
下载PDF
Failure characteristics and the damage evolution of a composite bearing structure in pillar-side cemented paste backfilling 被引量:2
16
作者 Boqiang Cui Guorui Feng +6 位作者 Jinwen Bai Gaili Xue Kai Wang Xudong Shi Shanyong Wang Zehua Wang Jun Guo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第8期1524-1537,共14页
A backfilling body-coal pillar-backfilling body(BPB)structure formed by pillar-side cemented paste backfilling can bear overburden stress and ensure safe mining.However,the failure response of BPB composite samples mu... A backfilling body-coal pillar-backfilling body(BPB)structure formed by pillar-side cemented paste backfilling can bear overburden stress and ensure safe mining.However,the failure response of BPB composite samples must be investigated.This paper examines the deformation characteristics and damage evolution of six types of BPB composite samples using a digital speckle correlation method under uniaxial compression conditions.A new damage evolution equation was established on the basis of the input strain energy and dissipated strain energy at the peak stress.The prevention and control mechanisms of the backfilling body on the coal pillar instability were discussed.The results show that the deformation localization and macroscopic cracks of the BPB composite samples first appeared at the coal-backfilling interface,and then expanded to the backfilling elements,ultimately appearing in the coal elements.The elastic strain energy in the BPB composite samples reached a maximum at the peak stress,whereas the dissipated energy continued to accumulate and increase.The damage evolution curve and equation agree well with the test results,providing further understanding of instability prevention and the control mechanisms of the BPB composite samples.The restraining effect on the coal pillar was gradually reduced with decreasing backfilling body element's volume ratio,and the BPB composite structure became more vulnerable to failure.This research is expected to guide the design,stability monitoring,instability prevention,and control of BPB structures in pillar-side cemented paste backfilling mining. 展开更多
关键词 backfilling body-coal pillar-backfilling body composite structure digital speckle correlation method uniaxial compression deformation characteristics damage evolution
下载PDF
The Fluid Traditional and Indigenous Structure of Climatism in Physical Architecture and Its Role in Hospital Construction 被引量:1
17
作者 Sania Sami Roughayeh Rezanejad Zanjany 《Journal of Building Construction and Planning Research》 2020年第1期1-13,共13页
The issue of climatism is a matter of concern today, given the growth of technology and the subject of globalization, which is defined and explained in many respects. The rapid advancement of technology makes communic... The issue of climatism is a matter of concern today, given the growth of technology and the subject of globalization, which is defined and explained in many respects. The rapid advancement of technology makes communication and navigation readily available. This factor causes the challenge for human societies to discover more recent developments that in turn raise the issues of how can the climatism be compatible with the creation of an architectural work, taking into account that the countries’ conventional boundaries lose their importance. And, the factors affect climatism, in other words, the way that climatism, human societies with diverse cultures, and the surrounding environment interact with each other, is raised. And, in general, the way that an architecture work to interact with its environment is discussed. In this sense, the traditional and indigenous architecture, and the fluidity of the region in the architectural framework also address the characteristics of the physical and architectural features of each region from the architectural arena, introducing effective approaches to architecture and urban planning (objective and tactical approaches), using the rational-logical approach to regional review. Then, the discussion of regionalism and regional influences in the physical fabric of each traditional architectural structure’s region is presented, with the special look of traditional architecture that is expressed in consistency between the building and the nature, and to explain the arguments to the examples and characteristics. 展开更多
关键词 REGIONALISM Climatism NATIVE ARCHITECTS FLUIDITY Body structural Archi-tects Health CENTERS Climatism in the HOSPITAL
下载PDF
PHYSICAL VALUE MAPPING ALGORITHM OF MESH IN FINE CAE ANALYSIS OF AUTOMOBILE BODY STRUCTURE 被引量:2
18
作者 Hu Ping Gong Kejia Bao Yidong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期338-341,共4页
A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from... A physical value mapping (PVM) algorithm based on finite element mesh from the stamped part in stamping process to the product is presented, In order to improve the efficiency of the PVM algorithm, a search way from the mesh of the product to the mesh of the stamped part will be adopted. At the same time, the search process is divided into two steps: entire search (ES) and local search (LS), which improve the searching efficiency. The searching area is enlarged to avoid missing projection elements in ES process. An arc-length method is introduced in LS process. The validity is confirmed by the results of the complex industry-forming product. 展开更多
关键词 Fine CAE analysis of auto body structure Finite element mesh Arc method Physical value mapping
下载PDF
Optimized body structure and packaging for car ODB impact performance 被引量:1
19
作者 Men Yongxin Ma Fangwu +2 位作者 Wang Zhitao Wang Zelong Peng Hong 《Engineering Sciences》 EI 2012年第6期43-46,共4页
Front bumper, crash box and side rail are key body structural parts in front crash. Deformation space is affected by compartment packaging. The improvement suggestions are proposed to solve the problems existed in the... Front bumper, crash box and side rail are key body structural parts in front crash. Deformation space is affected by compartment packaging. The improvement suggestions are proposed to solve the problems existed in the current vehicle struc- ture and compartment packaging based on the areas that influence performance of automobile offset deformable barrier impact, such as the side rail, mounting, storage battery packaging,etc. It is proved that dO % offset crash simulation result of one certain car is well-correlated with the physical test. Optimization cases meet the crash performance requirements. The objec- tive of the analysis is to guide structural design and improves a car' s crash safety performance. 展开更多
关键词 PACKAGING offset deformable barrier impact body structure crash performance optimization
下载PDF
Fully nonlinear modeling of radiated waves generated by floating flared structures 被引量:3
20
作者 Bin-Zhen Zhou De-Zhi Ning +1 位作者 Bin Teng Ming Zhao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第5期667-680,共14页
The nonlinear radiated waves generated by a structure in forced motion, are simulated numerically based on the potential theory. A fully nonlinear numerical model is developed by using a higher-order boundary element ... The nonlinear radiated waves generated by a structure in forced motion, are simulated numerically based on the potential theory. A fully nonlinear numerical model is developed by using a higher-order boundary element method (HOBEM). In this model, the instantaneous body position and the transient free surface are updated at each time step. A Lagrangian technique is employed as the time marching scheme on the free surface. The mesh regridding and interpolation methods are adopted to deal with the possible numerical instability. Several auxiliary functions are proposed to calculate the wave loads indirectly, instead of directly predicting the temporal derivative of the velocity potential. Numerical experiments are carried out to simulate the heave motions of a submerged sphere in infinite water depth, the heave and pitch motions of a truncated flared cylinder in finite depth. The results are verified against the published numerical results to ensure the effectiveness of the proposed model. Moreover, a series of higher harmonic waves and force components are obtained by the Fourier transformation to investigate the nonlinear effect of oscillation frequency. The difference among fully nonlinear, body-nonlinear and linear results is analyzed. It is found that the nonlinearity due to free surface and body surface has significant influences on the numerical results of the radiated waves and forces. 展开更多
关键词 Wave radiation Fully nonlinear Body- nonlinear HOBEM Flared structure
下载PDF
上一页 1 2 154 下一页 到第
使用帮助 返回顶部