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“3 Degrees and 8 Combinations” Teaching Mode of Anti-Seismic Design of Building Structures
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作者 Huina Li 《Journal of Contemporary Educational Research》 2023年第4期12-17,共6页
Earthquakes pose a significant threat to people’s property and personal safety.Improving the teaching of civil engineering and building structure anti-seismic design courses can enable students to do a good job in an... Earthquakes pose a significant threat to people’s property and personal safety.Improving the teaching of civil engineering and building structure anti-seismic design courses can enable students to do a good job in anti-seismic design in the future and effectively reduce the damage on buildings caused by earthquakes.In this paper,we analyzed the basic characteristics of a course in civil engineering major,which is Anti-Seismic Design of Building Structures,and the shortcomings of traditional teaching.It is proposed that the 3-degrees and 8-combinations teaching mode of anti-seismic design of building structures can effectively improve students’autonomy and enthusiasm in learning,helps to cultivate professional ethics among students,and improve their ability to apply what they have learned. 展开更多
关键词 anti-seismic Design of Building structures 3-Degrees and 8-Combinations anti-seismic structure
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Construction of Teaching Case Base of Anti-Seismic Design of Building Structure
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作者 Huina Li 《Journal of Architectural Research and Development》 2023年第3期13-18,共6页
Anti-Seismic Design of Building Structures is an important course in civil engineering majors,and it is also a course that pays equal attention to theory and practice.Therefore,by establishing a case base for Anti-Sei... Anti-Seismic Design of Building Structures is an important course in civil engineering majors,and it is also a course that pays equal attention to theory and practice.Therefore,by establishing a case base for Anti-Seismic Design of Building Structures,the obscure theoretical knowledge can be taught to students in the form of examples,and the knowledge becomes intuitive.In this way,the students’understanding of anti-seismic design theory and the efficiency of teaching can be improved,and the students’interest in learning can be stimulated. 展开更多
关键词 Building structure anti-seismic design Case base
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Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents
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作者 Yanjing Cao Chenchen Xu +2 位作者 Qi Li Shan Lu Jing Xiao 《International Journal of Mental Health Promotion》 2024年第4期261-269,共9页
Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of thes... Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of these measures over time remains understudied.This research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese teenagers.Method:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D assessment.After a three-month interval,967 of these participants repeated the CES-D evaluation.The study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural integrity.We investigated factorial invariance by conducting a twopronged CFA:one comparing urban vs.rural backgrounds,and another contrasting the results from the initial assessment with those from the follow-up.Results:The CES-D demonstrated adequate reliability in both rural and urban high school student samples.The preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected data.Invariance tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s invariance.Conclusions:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese adolescents.Its applicability is consistent across different living environments and remains stable over time. 展开更多
关键词 DEPRESSION factor structure measurement invariance Chinese adolescent longitudinal invariance
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Structural Health Monitoring by Accelerometric Data of a Continuously Monitored Structure with Induced Damages
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作者 Giada Faraco Andrea Vincenzo De Nunzio +1 位作者 Nicola Ivan Giannoccaro Arcangelo Messina 《Structural Durability & Health Monitoring》 EI 2024年第6期739-762,共24页
The possibility of determining the integrity of a real structure subjected to non-invasive and non-destructive monitoring,such as that carried out by a series of accelerometers placed on the structure,is certainly a g... The possibility of determining the integrity of a real structure subjected to non-invasive and non-destructive monitoring,such as that carried out by a series of accelerometers placed on the structure,is certainly a goal of extreme and current interest.In the present work,the results obtained from the processing of experimental data of a real structure are shown.The analyzed structure is a lattice structure approximately 9 m high,monitored with 18 uniaxial accelerometers positioned in pairs on 9 different levels.The data used refer to continuous monitoring that lasted for a total of 1 year,during which minor damage was caused to the structure by alternatively removing some bracings and repositioning them in the structure.Two methodologies detecting damage based on decomposition techniques of the acquired data were used and tested,as well as a methodology combining the two techniques.The results obtained are extremely interesting,as all the minor damage caused to the structure was identified by the processing methods used,based solely on the monitored data and without any knowledge of the real structure being analyzed.The results use 15 acquisitions in environmental conditions lasting 10 min each,a reasonable amount of time to get immediate feedback on possible damage to the structure. 展开更多
关键词 structural health monitoring damage detection vibration measurements stochastic subspace identification
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Measurement Research Based on Bayesian Structural Equation Cognitive Model
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作者 Shuixian Fei Sanzhi Shi +4 位作者 Jixin Li Jiali Zheng Xinyi Yu Yifan Huang Xiang Li 《Journal of Applied Mathematics and Physics》 2024年第4期1163-1177,共15页
The Bayesian structural equation model integrates the principles of Bayesian statistics, providing a more flexible and comprehensive modeling framework. In exploring complex relationships between variables, handling u... The Bayesian structural equation model integrates the principles of Bayesian statistics, providing a more flexible and comprehensive modeling framework. In exploring complex relationships between variables, handling uncertainty, and dealing with missing data, the Bayesian structural equation model demonstrates unique advantages. Therefore, Bayesian methods are used in this paper to establish a structural equation model of innovative talent cognition, with the measurement of college students’ cognition of innovative talent being studied. An in-depth analysis is conducted on the effects of innovative self-efficacy, social resources, innovative personality traits, and school education, aiming to explore the factors influencing college students’ innovative talent. The results indicate that innovative self-efficacy plays a key role in perception, social resources are significantly positively correlated with the perception of innovative talents, innovative personality tendencies and school education are positively correlated with the perception of innovative talents, but the impact is not significant. 展开更多
关键词 Bayesian structural Equation Model Innovative Talents measure of Cognition Innovative Self-Efficacy Social Resources
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MEASURING STRUCTURE COMPLEXITY OF UML CLASS DIAGRAMS 被引量:6
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作者 Zhou Yuming Xu Baowen (Dept. of Computer Science & Eng., Southeast Univ., Nanjing 210096) (State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072) (Jiangsu Key Lab. of Computer Info. Proc. Tech., Soochow Univ., Suzhou 215006) 《Journal of Electronics(China)》 2003年第3期227-231,共5页
To provide system designer a valid measure to evaluate the structure complexityof class diagrams objectively, this letter first proposes a method to transform a class diagramsinto a weighted class dependence graph, th... To provide system designer a valid measure to evaluate the structure complexityof class diagrams objectively, this letter first proposes a method to transform a class diagramsinto a weighted class dependence graph, then presents a structure complexity measure for classdiagrams based on entropy distance. 展开更多
关键词 Class diagrams structure complexity measurE Entropy distance DEPENDENCE
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A Method for Measuring the Structure Complexity of Web Application
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作者 MAO Cheng-ying LU Yan-sheng 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期143-150,共8页
The precise and effective measure results of Web applications not only facilitate good comprehension of them, but also benefit to the macro-management of software activities, such as testing, reverse engineering, reus... The precise and effective measure results of Web applications not only facilitate good comprehension of them, but also benefit to the macro-management of software activities, such as testing, reverse engineering, reuse, etc. The paper exploits some researches on measuring the structure complexity of Web application. Through a deep analysis of the configuration and objects' interactions of Web system, two conclusions have been drawn:① A generic Web application consists of static web page, dynamic page, component and database object; ② The main interactions have only three styles, that is static link, dynamic link and call/return relation. Based on analysis and modeling of the content of a Web page (static or dynamic), complexity measure methods of both control logic of script and nesting of HTML code are further discussed. In addition, two methods for measuring the complexity of inte〉page navigation are also addressed by modeling the inte〉page navigation behaviors of Web application via WNG graph. 展开更多
关键词 structure complexity measure DD graph HTree tree WNG graph
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Single-borehole measuring method for broken rock zone in gently inclined thin layer weakness structure
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作者 陈庆发 周科平 +1 位作者 龙腾腾 高峰 《Journal of Coal Science & Engineering(China)》 2008年第2期200-204,共5页
According to the structural characteristics of gently inclined thin layer rock mass in which lots of weak interlayer existed,the concept of gently inclined thin layer weakness structure was proposed.If single-borehole... According to the structural characteristics of gently inclined thin layer rock mass in which lots of weak interlayer existed,the concept of gently inclined thin layer weakness structure was proposed.If single-borehole measuring method of the acoustic along the conventional arrangement mode was used in measuring the broken rock zone in this structure,the change of the relationship curves (Vp-L) between acoustic p-wave velocity (Vp) and borehole depth (L) would present the irregular feature due to the mechanical characteristics of layered rock mass and harmful effects of weak interlayers,and the scope of broken rock zone couldn't be defined quickly.Based on the analysis of the me- chanical characteristics of layered rock mass,the propagation rule of acoustic and distri- butions characteristics of plastic zone and slip zone in layered rock mass,new arrange- ment mode of acoustic measuring boreholes for broken rock zone in gently inclined thin layer weakness structure was proposed.Namely,the measuring boreholes in two sides were parallel to the strata,the measuring boreholes in the roof and floor perpendicular to the strata.Besides the controlling depth of the measuring boreholes in the scope of the large plastic zones or the large slip zones should be increased.Engineering example showed that new acoustic measuring boreholes arrangement mode had the better appli- cability and could determine the scope of the broken rock zone in the gently inclined thin layer weakness structure quickly. 展开更多
关键词 single-borehole measuring method broken rock zone gently inclined thin layer weakness structure acoustic measuring
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A New Technology to Measure the Thermoelectric Performance of Nanowire Array Structure 被引量:1
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作者 王为 王惠 高建平 《Transactions of Tianjin University》 EI CAS 2002年第4期243-245,共3页
Recently, the study on one-dimensional thermoelectric materials is getting more and more attention. For those one-dimensional thermoelectric materials with nanowire array structure fabricated with alumina film as temp... Recently, the study on one-dimensional thermoelectric materials is getting more and more attention. For those one-dimensional thermoelectric materials with nanowire array structure fabricated with alumina film as template, its thickness is often in the range of 10 to several tens micrometers, and the conventional measurement cannot be used. The key difficulties of the thermoelectric performance measurement for nanowire array materials include two aspects: 1) How to heat the two sides of the specimen uniformly and keep the temperature difference constantly at the same time; 2) How to measure the temperature of the two sides of the specimen with the thickness of 10 to several tens micrometers. A new type heating and temperature measuring technology has been used, and it can be simply described as liquid heating and separate temperature measurement. According to this principle, a thermoelectric performance measurement system has been established. 展开更多
关键词 measuring technology thermoelectric performance nanowire array structure thermoelectric materials
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Synthesis, performance and structure characterization of glyoxal-monomethylolurea-melamine (G-MMU-M) co-condensed resin 被引量:1
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作者 Haixiang Liu Jun Zhang +3 位作者 Chunlei Dong Gang Zhu Guanben Du Shuduan Deng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期92-104,共13页
In order to reduce the formaldehyde emission of formaldehyde-based wood adhesive from the source,it is aimed to develop a novel co-condensed resin of glyoxal-monomethylolurea-melamine(G-MMU-M).A series of G-MMU-M resi... In order to reduce the formaldehyde emission of formaldehyde-based wood adhesive from the source,it is aimed to develop a novel co-condensed resin of glyoxal-monomethylolurea-melamine(G-MMU-M).A series of G-MMU-M resins with various formulations of raw materials were successfully prepared.The basic properties and bonding performance of the G-MMU-M resins were determined.Furthermore,the structures of resins were characterized by FTIR,^(13)C NMR,XPS,and ESI-MS.The results show that the prepared G-MMU-M resin remains stable for 30 d,meanwhile,the dry and wet bonding strength of the plywoods bonded with the resins,solid content and viscosity are influenced greatly by the addition amount of melamine and MMU/G molar ratio.The G-MMU-M resins with MMU/G molar ratio of 0.9:1.0 and 8% melamine exhibit the highest dry and bonding strength of 1.98 MPa and 1.27 MPa,increased by 34% and 63%,respectively,in comparison with glyoxal-monomethylolurea(G-MMU)resin.In the G-MMU-M resins,there were four main oligomers including M—CH(—^(+)CH-MMU)-O-MMU,M-CH(—CH_(2)OH)-MMU-O-MMU,M—CH(—OH)—^(+)CH-MMU-O-MMU,and M—CH(—^(+)CH-MMU)-MMU-p-G. 展开更多
关键词 Wood adhesive Glyoxal-monomethylolurea-melamine SYNTHESIS Chemical reaction measurement structure
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Vector-intensity measure based seismic vulnerability analysis of bridge structures 被引量:8
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作者 Li Zhongxian Li Yang Li Ning 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第4期695-705,共11页
This paper presents a method for seismic vulnerability analysis of bridge structures based on vector-valued intensity measure (viM), which predicts the limit-state capacities efficiently with multi-intensity measure... This paper presents a method for seismic vulnerability analysis of bridge structures based on vector-valued intensity measure (viM), which predicts the limit-state capacities efficiently with multi-intensity measures of seismic event. Accounting for the uncertainties of the bridge model, ten single-bent overpass bridge structures are taken as samples statistically using Latin hypercube sampling approach. 200 earthquake records are chosen randomly for the uncertainties of ground motions according to the site condition of the bridges. The uncertainties of structural capacity and seismic demand are evaluated with the ratios of demand to capacity in different damage state. By comparing the relative importance of different intensity measures, Sa(T1) and Sa(T2) are chosen as viM. Then, the vector-valued fragility functions of different bridge components are developed. Finally, the system-level vulnerability of the bridge based on viM is studied with Duunett- Sobel class correlation matrix which can consider the correlation effects of different bridge components. The study indicates that an increment IMs from a scalar IM to viM results in a significant reduction in the dispersion of fragility functions and in the uncertainties in evaluating earthquake risk. The feasibility and validity of the proposed vulnerability analysis method is validated and the bridge is more vulnerable than any components. 展开更多
关键词 bridge structure seismic vulnerability analysis vector-valued intensity measure components' correlation system vulnerability
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Field Measurements of Influence of Sand Transport Rate on Structure of Wind-sand Flow over Coastal Transverse Ridge 被引量:10
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作者 DONG Yuxiang S L NAMIKAS +1 位作者 P A HESP MA Jun 《Chinese Geographical Science》 SCIE CSCD 2008年第3期255-261,共7页
The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Prov... The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei Province, which is one of the most typical coastal aeolian distribution regions in China and famous for the tall and typical coastal transverse ridges. The measurement results show that, on the conditions of approximate wind velocities and same surface materials and environments, some changes happen to the structure of wind-sand flow with the increase of total sand transport rate on the crest of coastal transverse ridge. First, the sand transport rates of layers at different heights in the wind-sand flow increase, with the maximum increase at the height layer of 4-8cm. Second, the ratios of sand trans-port rates of layers at different heights to total sand transport rate decrease at the low height layer (0-4cm), but increase at the high height layer (4-60cm). Third, the distribution of the sand transport rate in the wind-sand flow can be expressed by an exponential function at the height layer of 0-40cm, but it changes from power function model to ex-ponential function model in the whole height layer (0-60cm) and changes into polynomial function model at the height layer of 40-60cm with the increase of total sand transport rate. Those changes have a close relationship with the limit of sand grain size of wind flow transporting and composition of sand grain size in the wind-sand flow. 展开更多
关键词 sand transport rate coastal transverse ridge structure of wind-sand flow field measurement
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A comparison of summer precipitation structures over the South China Sea and the East China Sea based on tropical rainfall measurement mission 被引量:3
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作者 LI Jiangnan YANG Chaofeng +2 位作者 LI Fangzhou HE Qihua LI Weibiao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第11期41-49,共9页
The three-dimensional structures of summer precipitation over the South China Sea (SCS) and the East China Sea (ECS) are investigated based on tropical rainfall measurement mission (TRMM). The primary results ar... The three-dimensional structures of summer precipitation over the South China Sea (SCS) and the East China Sea (ECS) are investigated based on tropical rainfall measurement mission (TRMM). The primary results are as follows. First, both the convective and stratiform precipitation rates in the SCS are much higher than those of the ECS. The contribution of the convective cloud precipitation to the surface precipitation is primarily over the SCS and the ECS with a proportion of about 70%, but the contribution of convective cloud precipitation is slightly larger in the SCS than the ECS. The contribution of stratus precipitation is slightly larger in the ECS than that in the SCS. Second, the content of cloud particles and precipitation particles in the ECS in June was greater than that in the SCS, while in July and August, the content of cloud and precipitation particles in the ECS was less than that in the SCS. Third, the latent heat profile of the ECS is quite different from that of the SCS. In June, the peak values of evaporation and condensation latent heating rates in the ECS are greater than those in the SCS. In July and August, however, the peak values of evaporation and condensation latent heating rates in the ECS are about 0.05°/h less than those in the SCS. 展开更多
关键词 PRECIPITATION three-dimensional structures tropical rainfall measurement mission SouthChina Sea East China Sea
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Problems of durability and reinforcement measures for underground structures in China 被引量:1
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作者 Xianming Zeng Zhenyu Wang +3 位作者 Junqi Fan Lin Zhao Dalu Lin Jian Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第3期250-259,共10页
In this paper, the bolt- and cable-supported structures mainly refer to anchored cables, anchored bolts, soil nails and other commonly used reinforcing and supporting structures in geotechnical engineering, as well as... In this paper, the bolt- and cable-supported structures mainly refer to anchored cables, anchored bolts, soil nails and other commonly used reinforcing and supporting structures in geotechnical engineering, as well as reinforced soil structures in permanent works. They are often used in combination, or formed into composite bolt-and cable-supported structures, with other traditional construction methods and relevant measures. Distinct characteristics of such structures are that they are most often invisible, exposed to more severe underground corrosive environments and with strict durability requirements. A number of serious durability problems of underground structures are discussed and major achievements and advances in China and abroad in terms of durability and reinforcement measures for underground structures are reviewed, followed by comprehensive analyses. Some suggestions for those problems are put forward. 展开更多
关键词 underground structures DURABILITY service life reinforcement measures
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Eco-environmental Impact Assessment of the Change of Regional Industrial Structure and Regulative Measures 被引量:2
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作者 Zhang Jian 《Chinese Journal of Population,Resources and Environment》 北大核心 2008年第2期8-17,共10页
Acting as an important driving force for the change of the regional land use,the change of industrial structure also has some influences on the ecological environment.The assessment and mechanism analysis of these inf... Acting as an important driving force for the change of the regional land use,the change of industrial structure also has some influences on the ecological environment.The assessment and mechanism analysis of these influences will be beneficial to the sustainable development of regional economy and the im- provement of relationships between man and earth.Taking Chuzhou City in Anhui Province as an example,on the basis of a qualitative analysis of the influence of the development of differ- ent industry on the regional ecological environment,this paper builds the influence factor of industrial structure on natural envi- ronment and the influence index of industrial structure on natural environment,makes a quantitative assessment of the change of the industrial structure and its comprehensive influences on the eco- logical environment in the Chuzhou City from 1974 to 1995. Studies show that,during the analysed period,Chuzhou City's industrial structure has changed markedly,having undergone two transformations.The influence of industrial structure on natural environment from 1974 to 1995 increased as a whole,while from 1996 to 2004,the influence of industrial structure on natural en- vironment decreased year-on-year.These changes indicate that the regional change of industrial structure results in better ecological effects.Finally,we propose appropriate regulatory measures ac- cording to our research results. 展开更多
关键词 change of industrial structure eco-environmental effect Chuzhou City measures
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Evolution of the Spatial Distribution of Basic Infrastructures and Services in the Niakhar Area (Fatick), Senegal
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作者 Alphousseyni Ndonky Mouhamadou Moustapha Mbacké Ndour +1 位作者 Pape Boubou Sow Rosalie Diouf 《Journal of Geographic Information System》 2023年第6期611-628,共18页
Basic infrastructures and services present an important socio-economic and territorial equity issue, because the availability of these makes it possible to improve the living conditions of populations, makes territori... Basic infrastructures and services present an important socio-economic and territorial equity issue, because the availability of these makes it possible to improve the living conditions of populations, makes territories attractive and stimulates their development. The objective of our study has been achieved, so our results provided information on the rate of propagation of basic infrastructures and services, as well as the evolution of the forms of spatial distribution of the latter. The data used comes from the census and geolocation of basic infrastructures and services in the Niakhar area, carried out by the IRD in 2018. Centrographic measurements were used to describe the overall spatial distribution and the use of chi-square statistics confirmed the existence of a preferential direction of distribution. To verify the existence of a spatial structure of infrastructure and service seeding, the Ripley statistic is used. Our results can be useful for land use planning and spatial resource allocation policies. Indeed, the identification of different types of spatial aggregates and the highlighting of the preferred directions of the distribution of basic infrastructures and services, make it possible to correct disparities in the spatial distribution of basic resources. 展开更多
关键词 Spatial structure Spatial Disparities Ripley Statistic Centrographic measurements
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Inversion of thicknesses of multi-layered structures from eddy current testing measurements 被引量:1
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作者 黄平捷 吴昭同 《Journal of Zhejiang University Science》 EI CSCD 2004年第1期86-91,共6页
Luquire et al. ' s impedance change model of a rectangular cross section probe coil above a structure with an arbitrary number of parallel layers was used to study the principle of measuring thicknesses of multi-l... Luquire et al. ' s impedance change model of a rectangular cross section probe coil above a structure with an arbitrary number of parallel layers was used to study the principle of measuring thicknesses of multi-layered structures in terms of eddy current testing voltage measurements. An experimental system for multi-layered thickness measurement was developed and several fitting models to formulate the relationships between detected impedance/voltage measurements and thickness are put forward using least square method. The determination of multi-layered thicknesses was investigated after inversing the voltage outputs of the detecting system. The best fitting and inversion models are presented. 展开更多
关键词 Multi layered structure Thickness measurement Eddy current testing Multi frequency INVERSION
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MULTIPARAMETER MEASUREMENT FOR RACEWAY GROOVE OF BEARING BASED ON 3D RECONSTRUCTION WITH DIGITAL STRUCTURED LIGHT 被引量:1
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作者 He Tao Zhong Ming LiWei Zhong Yuning Shi Tielin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期470-472,共3页
A fast 3D reconstruction method based on structured light to measure various parameters of the raceway groove is presented. Digital parallel grating stripes distributed with sine density are projected onto the raceway... A fast 3D reconstruction method based on structured light to measure various parameters of the raceway groove is presented. Digital parallel grating stripes distributed with sine density are projected onto the raceway groove by a DLP projector, and distorting of stripes is happened on the raceway. Simultaneously, aided by three-step phase-shifting approach, three images covered by different stripes are obtained by a high-resolution CCD camera at the same location, thus a more accuracy local topography can be obtained. And then the bearing is rotated on a high precision computer controlled rotational stage. Three images are also obtained as the former step at next planned location triggered by the motor. After one cycle, all images information is combined through the mosaics. As a result, the 3D information of raceway groove can be gained. Not only geometric properties but also surface flaws can be extracted by software. A preliminary hardware system has been built, with which some geometric parameters have been extracted from reconstructed local topography. 展开更多
关键词 structured light Fringe projection Phase-shifting Multiparameter measurement 3D reconstruction
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Multilevel Tests and Measurement Evaluation Methods for the Application of Composite Materials in Spacecraft Structures 被引量:1
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作者 WANG Yuhang GUO Liangshuai +2 位作者 ZHOU Peng ZHANG Tao WANG Fuhui 《上海航天(中英文)》 CSCD 2022年第1期111-121,共11页
With the implementation of new-generation launch vehicles,space stations,lunar and deep space exploration,etc.,the development of spacecraft structures will face new challenges. In order to reduce the spacecraft weigh... With the implementation of new-generation launch vehicles,space stations,lunar and deep space exploration,etc.,the development of spacecraft structures will face new challenges. In order to reduce the spacecraft weight and increase the payload,composite material structures will be widely used. It is difficult to evaluate the strength and life of composite materials due to their complex mechanism and various phenomena in damage and failure.Meanwhile,the structures of composite materials used in spacecrafts will bear complex loads,including the coupling loads of tension,pressure,bending,shear,and torsion. Static loads,thermal loads,and vibration loads may occur at the same time,which asks for verification requirements to ensure the structure safety. Therefore,it is necessary to carry out a systematic multi-level experimental study. In this paper,the building block approach (BBA) is used to investigate the multilevel composite material structures for spacecrafts. The advanced measurement technology is adopted based on digital image correlation (DIC) and piezoelectric and optical fiber sensors to measure the composite material structure deformation. The virtual experiment technology is applied to provide sufficient and reliable data for the evaluation of the composite material structures of spacecrafts. 展开更多
关键词 composite material structure SPACECRAFT multilevel test measurement evaluation
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Spatial effect of environmental regulation measures on industrial structure upgrading from the empirical analysis of Beijing-Tianjin-Hebei region and its surrounding areas 被引量:1
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作者 Guoxing Zhang Peide Zhang +2 位作者 Nana Deng Haixu Bao Jiexun Li 《Chinese Journal of Population,Resources and Environment》 2019年第3期267-277,共11页
This paper investigates the spatial effect of environmental regulation measures on the upgrading of industrial structure in the integrated development strategy of Beijing-Tianjin-Hebei region and its surrounding areas... This paper investigates the spatial effect of environmental regulation measures on the upgrading of industrial structure in the integrated development strategy of Beijing-Tianjin-Hebei region and its surrounding areas.In order to reflect the effect of the environmental regulation and different regulation measures more truly,this paper constructs indices of the environmental regulation measures through the results of policy texts quantification.On the basis of the previous research,this paper divides environmental regulation into the following types:personnel and administrative measures of command and control;market-oriented fiscal,taxation,financial and other economic measures;guidance measures.Spatial panel regression results show that administrative measures of command control and market-oriented fiscal measures have a significant role in promoting regional industrial structure upgrading,but not conducive to the advancement of the industrial structure of adjacent areas.Their roles in promoting and inhibition are counteracted,which causes the total effect of industrial structure upgrading of Beijing-Tianjin-Hebei and the surrounding areas are not significant.Personnel measures,financial measures,other economic measures and guidance measures do not have the short-term effect and spatial effect on the upgrading of industrial structure. 展开更多
关键词 Beijing-Tianjin-Hebei and its surrounding areas policy quantification environmental regulatory measures upgrading of industrial structure
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