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A theory for three-dimensional response of micropolar plates 被引量:1
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作者 Dianwu HUANG Linghui HE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第8期1403-1414,共12页
Through combined applications of the transfer-matrix method and asymptotic expansion technique,we formulate a theory to predict the three-dimensional response of micropolar plates.No ad hoc assumptions regarding throu... Through combined applications of the transfer-matrix method and asymptotic expansion technique,we formulate a theory to predict the three-dimensional response of micropolar plates.No ad hoc assumptions regarding through-thickness assumptions of the field variables are made,and the governing equations are two-dimensional,with the displacements and microrotations of the mid-plane as the unknowns.Once the deformation of the mid-plane is solved,a three-dimensional micropolar elastic field within the plate is generated,which is exact up to the second order except in the boundary region close to the plate edge.As an illustrative example,the bending of a clamped infinitely long plate caused by a uniformly distributed transverse force is analyzed and discussed in detail. 展开更多
关键词 micropolar plate TRANSFER-MATRIX asymptotic expansion three-dimensional response
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Modeling mechanistic responses in asphalt pavements under three-dimensional tire-pavement contact pressure 被引量:9
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作者 胡小弟 L.F.WALUBITA 《Journal of Central South University》 SCIE EI CAS 2011年第1期250-258,共9页
A three dimensional finite element program incorporating actually measured vertical tire-pavement contact pressure(TPCP) was utilized for modeling the mechanistic responses in asphalt concrete(AC) layers by simulating... A three dimensional finite element program incorporating actually measured vertical tire-pavement contact pressure(TPCP) was utilized for modeling the mechanistic responses in asphalt concrete(AC) layers by simulating various vehicle motions:stationary and non-stationary(i.e.in acceleration or deceleration mode).Analysis of the results indicated the following items.1) It is critical to use the vertical TPCP as the design control criteria for the tensile strains at the bottom of the AC layer when the base layer modulus is lower in magnitude(e.g.≤400 MPa);however,when the base layer modulus is higher in magnitude(e.g.≥7 000 MPa),the horizontal TPCP and the tensile strains in the X-direction at the surface of the AC layer should also be considered as part of the design response criteria.2) The definition of "overload" needs to be revised to include tire pressure over-inflation,i.e.,a vehicle should be considered to be overloaded if the wheel load exceeds the specification and/or the tire inflation pressure is higher than the specification.3) Light trucks have more structural impact on the strain responses and pavement design when the thickness of the surfacing AC layer is thinner(e.g.≤50 mm).4) The acceleration of a vehicle does not significantly impact the AC surface distresses such as rutting at the top of the upgrade slopes or intersections;however,vehicle deceleration can dramatically induce horizontal shear strains and consequently,aggravate shoving and rutting problems at the highway intersections.Evidently,these factors should be taken into account during mechanistic stress-strain modeling and structural design of asphalt pavements. 展开更多
关键词 asphalt pavement tire-pavement contact pressure vehicle acceleration mechanistic response three-dimensional finiteelement
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Three-Dimensional Exact Solution for Dynamic Damped Response of Plates with Two Free Edges
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作者 Le Wang Muchun Yu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第3期79-90,共12页
A three-dimensional state space method has been developed for the calculation of dynamic response of plates with two free edges and two simply supported edges.A complex damping model was introduced, then the exact sol... A three-dimensional state space method has been developed for the calculation of dynamic response of plates with two free edges and two simply supported edges.A complex damping model was introduced, then the exact solutions which satisfy all the governing equations and boundary conditions were obtained.In order to overcome the difficulty of satisfying all the stress conditions at free edges, the displacement functions of free edges were assumed.The boundary conditions were strictly satisfied when the convergence rate was good.The computing time was evidently less than that of finite element method.The comparison of the solution with those of finite element method show that there is an excellent agreement for displacements.When the imaginary parts of normal stress deviated, the finite element results showed existence of shear stresses at top and bottom surfaces, and the boundary conditions of FEM model were not strictly satisfied. 展开更多
关键词 three-dimensional EXACT solution state space method free edge response
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Optimization of Three-Dimensional Culture Conditions of HepG2 Cells with Response Surface Methodology Based on the VitroGel System
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作者 WANG Jing Bo QIN Wen +7 位作者 YANG Zhuo SHEN Shi MA Yan WANG Li Yuan ZHUO Qin GONG Zhao Long HUO Jun Sheng CHEN Chen 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2022年第8期688-698,共11页
Objective This study optimizes three-dimensional(3D) culture conditions of HepG2 using response surface methodology(RSM) based on the VitroGel system to facilitate the cell model in vitro for liver tissues.Method HepG... Objective This study optimizes three-dimensional(3D) culture conditions of HepG2 using response surface methodology(RSM) based on the VitroGel system to facilitate the cell model in vitro for liver tissues.Method HepG2 cell was 3D cultured on the VitroGel system.Cell viability was detected using Cell Counting Kit-8(CCK-8) assay of HepG2 lived cell numbers.The proliferation of HepG2 cell and clustering performance was measured via fluorescence staining test.Albumin concentration in the culture medium supernatant as an index of HepG2 cell biological function was measured with ELISA kit.Independent factor tests were conducted with three key factors:inoculated cell concentration,cultured time,and dilution degree of the hydrogel.The preliminary results of independent factor tests were used to determine the levels of factors for RSM.Result The selected optimal culture conditions are as follows:concentration of inoculated cells was4.44 × 10^(5)/mL,culture time was 4.86 days,and hydrogel dilution degree was 1:2.23.The result shows that under optimal conditions,the predicted optical density(OD) value of cell viability was 3.10 and measured 2.978 with a relative error of 3.94%.Conclusion This study serves as a reference for the 3D HepG2 culture and constructs liver tissues in vitro.Additionally,it provides the foundation for repeated dose high-throughput toxicity studies and other scientific research work. 展开更多
关键词 response surface methodology The three-dimensional culture HYDROGEL
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Irradiation Response of Adipose-derived Stem Cells under Three-dimensional Culture Condition
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作者 DU Ya Rong PAN Dong +5 位作者 CHEN Ya Xiong XUE Gang REN Zhen Xin LI Xiao Man ZHANG Shi Chuan HU Bu Rong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期549-557,共9页
Objective Adipose tissue distributes widely in human body. The irradiation response of the adipose cells in vivo remains to be investigated. In this study we investigated irradiation response of adipose-derived stem c... Objective Adipose tissue distributes widely in human body. The irradiation response of the adipose cells in vivo remains to be investigated. In this study we investigated irradiation response of adipose-derived stem cells (ASCs) under three-dimensional culture condition. Methods ASCs were isolated and cultured in low attachment dishes to form three-dimensional (3D) spheres in vitro. The neuronal differentiation potential and stem-liked characteristics was monitored by using immunofluoresence staining and flow cytometry in monolayer and 3D culture. To investigate the irradiation sensitivity of 3D sphere culture, the fraction of colony survival and micronucleus were detected in monolayer and 3D culture. Soft agar assays were performed for measuring malignant transformation for the irradiated monolayer and 3D culture. Results The 3D cultured ASCs had higher differentiation potential and an higher stem-like cell percentage. The 3D cultures were more radioresistant after either high linear energy transfer (LET) carbon ion beam or low LET X-ray irradiation compared with the monolayer cell. The ASCs’ potential of cellular transformation was lower after irradiation by soft agar assay. Conclusion These findings suggest that adipose tissue cell are relatively genomic stable and resistant to genotoxic stress. 展开更多
关键词 Adipose-derived stem cells three-dimensional cell culture Irradiation response High-and low-LET irradiation
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QTL Identification of the Insensitive Response to Photoperiod and Temperature in Soybean by Association Mapping 被引量:6
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作者 ZUO Qiao-mei WEN Zi-xiang +4 位作者 ZHANG Shu-yun HOU Jin-feng GAI Jun-yi YU De-yue XING Han 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第8期1423-1430,共8页
The insensitive response to photoperiod and temperature is an important quantitative trait for soybean in wide adaptation breeding. The natural variation in response to photoperiod and temperature was detected using 2... The insensitive response to photoperiod and temperature is an important quantitative trait for soybean in wide adaptation breeding. The natural variation in response to photoperiod and temperature was detected using 275 accessions of soybean [Glycine max (L.) Merrill] from China. Genome-wide association mapping, based on population structure analysis, was carried out using 118 SSR markers by the TASSEL GLM (general linear model) program. Nine SSR markers (P〈0.01) were associated with the value of the response to photoperiod and temperature (VRPT) caused by days to flowering (DF), among which, Satt308 (LG M), Sattl50 (LG M) and Satt440 (LG l), were identified in both 2006 and 2007. Twelve SSR markers (P〈0.01) were associated with VRPT caused by days to maturity (DM), among which three markers, Satt387 (LG N), Satt307 (LG C2) and AW310961 (LG J), were detected in both 2006 and 2007. In addition, a total of 20 elite alleles were screened out over 2006 and 2007 for being associated with an insensitive response to photoperiod and temperature (IRPT) caused by DF and a total of seven different elite alleles were screened out for being associated with IRPT caused by DM. Among these elite alleles, five alleles, Satt150-244, Satt308-164, Satt308-206, Satt440-176, and Satt440-206, were associated with IRPT caused by DF and were identified in both years, but only one allele, Satt307-170, was identified as being associated with an IRPT caused by DM. Based on these elite alleles, a set of typical accessions were screened out. The result about the genetic basis of IRPT is meaningful for soybean wide adaption breeding. 展开更多
关键词 QTL association mapping SOYBEAN insensitive response photoperiod and temperature
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A modified method of discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces 被引量:13
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作者 Keshen Zhang Wei Wu +3 位作者 Hehua Zhu Lianyang Zhang Xiaojun Li Hong Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第3期571-586,共16页
This paper presents an automated method for discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces.Specifically,the method consists of five steps:(1)detection of trace feature points by... This paper presents an automated method for discontinuity trace mapping using three-dimensional point clouds of rock mass surfaces.Specifically,the method consists of five steps:(1)detection of trace feature points by normal tensor voting theory,(2)co ntraction of trace feature points,(3)connection of trace feature points,(4)linearization of trace segments,and(5)connection of trace segments.A sensitivity analysis was then conducted to identify the optimal parameters of the proposed method.Three field cases,a natural rock mass outcrop and two excavated rock tunnel surfaces,were analyzed using the proposed method to evaluate its validity and efficiency.The results show that the proposed method is more efficient and accurate than the traditional trace mapping method,and the efficiency enhancement is more robust as the number of feature points increases. 展开更多
关键词 Rock mass DISCONTINUITY three-dimensional point clouds Trace mapping
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Three-dimensional computed tomography mapping of posterior malleolar fractures 被引量:2
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作者 Qi-Hang Su Juan Liu +5 位作者 Yan Zhang Jun Tan Mei-Jun Yan Kai Zhu Jin Zhang Cong Li 《World Journal of Clinical Cases》 SCIE 2020年第1期29-37,共9页
BACKGROUND Posterior malleolar fractures have been reported to occur in<40%of ankle fractures.AIM To reveal the recurrent patterns and characteristics of posterior malleolar fractures by creating fracture maps of t... BACKGROUND Posterior malleolar fractures have been reported to occur in<40%of ankle fractures.AIM To reveal the recurrent patterns and characteristics of posterior malleolar fractures by creating fracture maps of the posterior malleolar fractures through the use of computed tomography mapping.METHODS A consecutive series of posterior malleolar fractures was used to create threedimensional reconstruction images,which were oriented and superimposed to fit an ankle model template by both aligning specific biolandmarks and reducing reconstructed fracture fragments.Fracture lines were found and traced in order to generate an ankle fracture map.RESULTS This study involved 112 patients with a mean age of 49,comprising 32 pronationexternal rotation grade IV fractures and 80 supination-external rotation grade IV fractures according to the Lauge-Hansen classification system.Three-dimensional maps showed that the posterior ankle fracture fragments in the supinationexternal rotation grade IV group were relatively smaller than those in the pronation-external rotation grade IV group after posterior malleolus fracture.In addition,the distribution analyses on posterior malleolus fracture lines indicated that the supination-external rotation grade IV group tended to have higher linear density but more concentrated and orderly distribution fractures compared to the pronation-external rotation grade IV group.CONCLUSION Fracture maps revealed the fracture characteristics and recurrent patterns of posterior malleolar fractures,which might help to improve the understanding of ankle fracture as well as increase opportunities for follow-up research and aid clinical decision-making. 展开更多
关键词 three-dimensional imaging mapS Ankle fractures Computed tomography
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Asymmetric image encryption algorithm based on a new three-dimensional improved logistic chaotic map 被引量:1
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作者 叶国栋 吴惠山 +1 位作者 黄小玲 Syh-Yuan Tan 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期153-163,共11页
Based on some analyses of existing chaotic image encryption frameworks and a new designed three-dimensional improved logistic chaotic map(3D-ILM),an asymmetric image encryption algorithm using public-key Rivest–Shami... Based on some analyses of existing chaotic image encryption frameworks and a new designed three-dimensional improved logistic chaotic map(3D-ILM),an asymmetric image encryption algorithm using public-key Rivest–Shamir–Adleman(RSA)is presented in this paper.In the first stage,a new 3D-ILM is proposed to enhance the chaotic behavior considering analysis of time sequence,Lyapunov exponent,and Shannon entropy.In the second stage,combined with the public key RSA algorithm,a new key acquisition mathematical model(MKA)is constructed to obtain the initial keys for the 3D-ILM.Consequently,the key stream can be produced depending on the plain image for a higher security.Moreover,a novel process model(NPM)for the input of the 3D-ILM is built,which is built to improve the distribution uniformity of the chaotic sequence.In the third stage,to encrypt the plain image,a pre-process by exclusive OR(XOR)operation with a random matrix is applied.Then,the pre-processed image is performed by a permutation for rows,a downward modulo function for adjacent pixels,a permutation for columns,a forward direction XOR addition-modulo diffusion,and a backward direction XOR addition-modulo diffusion to achieve the final cipher image.Moreover,experiments show that the the proposed algorithm has a better performance.Especially,the number of pixels change rate(NPCR)is close to ideal case 99.6094%,with the unified average changing intensity(UACI)close to 33.4634%,and the information entropy(IE)close to 8. 展开更多
关键词 three-dimensional improved logistic chaotic map(3D-ILM) Rivest–Shamir–Adleman(RSA)algorithm image encryption CONFUSION ENTROPY
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Slam Technology on Disaster Response
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作者 Zakari Tukur Ibrahim Junyi He 《World Journal of Engineering and Technology》 2024年第3期695-714,共20页
Disaster response demands rapid, accurate, and comprehensive situational awareness. This study explores the potential of Simultaneous Localization and Mapping (SLAM) technology to enhance disaster response efforts. By... Disaster response demands rapid, accurate, and comprehensive situational awareness. This study explores the potential of Simultaneous Localization and Mapping (SLAM) technology to enhance disaster response efforts. By integrating sensors and algorithms, SLAM enables autonomous systems to create detailed maps of disaster-stricken areas while simultaneously determining their own location. This research investigates the application of SLAM in various disaster scenarios, assesses its performance in challenging conditions, and analyzes its potential to improve search and rescue, damage assessment, and resource allocation. The findings highlight the advantages of SLAM in providing real-time data, supporting decision-making, and increasing the efficiency of disaster response operations. 展开更多
关键词 Autonomous Vehicles Disaster response SENSORS mapPING SLAM
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Prepulse inhibition (PPI) of tactile startle response in recombinant congenic strains of mice:QTL mapping and comparison with acoustic PPI
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作者 Adam Torkamanzehi Patricia Boksa Ridha Joober 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第3期139-151,共13页
Prepulse inhibition (PPI) of the startle response is a psychophysiological measure of sensorimotor gating believed to be cross-modal between different sensory systems. We analyzed the tactile startle response (TSR... Prepulse inhibition (PPI) of the startle response is a psychophysiological measure of sensorimotor gating believed to be cross-modal between different sensory systems. We analyzed the tactile startle response (TSR) and PPI of TSR (tPPI), using light as a prepulse stimulus, in the mouse strains A/J and C57BL/6J and 36 recombinant congenic strains derived from them. Parental strains were significantly different for TSR, but were comparable for tPPI. Among the congenic strains, variation for TSR was significant in both genetic backgrounds, but that of tPPI was significant only for the C57BL/6J background. Provisional mapping for loci modulating TSR and tPPI was carried out. Using mapping data from our previous study on acoustic startle responses (ASR) and PPI of ASR (aPPI), no common markers for aPPI and tPPI were identified. However, some markers were significantly associated with both ASR and TSR, at least in one genetic background. These results indicate cross-modal genetic regulation for the startle response but not for PPI, in these mouse strains. 展开更多
关键词 tactile startle response prepulse inhibition (PPI) acoustic startle response recombinant congenic strains of mice QTL mapping microsatellite markers
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Stochastic response analysis of noisy system with non-negative real-power restoring force by generalized cell mapping method
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作者 Qun HAN Wei XU Xiaole YUE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第3期329-336,共8页
The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping (GCM) method compute the transient and stationary probability density functions (PDFs) real... The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping (GCM) method compute the transient and stationary probability density functions (PDFs) real-power is used to Combined with the global properties of the noise-free system, the evolutionary process of the tran- sient PDFs is revealed. The results show that stochastic P-bifurcation occurs when the system parameter varies in the response analysis and the stationary PDF evolves from bimodal to unimodal along the unstable manifold during the bifurcation. 展开更多
关键词 stochastic response probability density function (PDF) generalized cell mapping (GCM) method real-power restoring force bifurcation
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Balanced Functional Maps for Three-Dimensional Non-Rigid Shape Registration
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作者 Xu-Peng Wang Hang Lei +1 位作者 Yan Liu Nan Sang 《Journal of Electronic Science and Technology》 CAS CSCD 2021年第4期369-378,共10页
Three-dimensional(3D)shape registration is a challenging problem,especially for shapes under non-rigid transformations.In this paper,a 3D non-rigid shape registration method is proposed,called balanced functional maps... Three-dimensional(3D)shape registration is a challenging problem,especially for shapes under non-rigid transformations.In this paper,a 3D non-rigid shape registration method is proposed,called balanced functional maps(BFM).The BFM algorithm generalizes the point-based correspondence to functions.By choosing the Laplace-Beltrami eigenfunctions as the function basis,the transformations between shapes can be represented by the functional map(FM)matrix.In addition,many constraints on shape registration,such as the feature descriptor,keypoint,and salient region correspondence,can be formulated linearly using the matrix.By bi-directionally searching for the nearest neighbors of points’indicator functions in the function space,the point-based correspondence can be derived from FMs.We conducted several experiments on the Topology and Orchestration Specification for Cloud Applications(TOSCA)dataset and the Shape Completion and Animation of People(SCAPE)dataset.Experimental results show that the proposed BFM algorithm is effective and has superior performance than the state-of-the-art methods on both datasets. 展开更多
关键词 Functional map(FM) Laplace-Beltrami operator shape registration three-dimensional(3D)non-rigid shape.
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Design and Realization of Block Level Augmented Reality Three-Dimensional Map
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作者 Dashuai Shang Chenguang Dai +1 位作者 Ying Yu Yabing Fan 《Journal of Computer and Communications》 2023年第6期113-121,共9页
In response to the construction needs of “Real 3D China”, the system structure, functional framework, application direction and product form of block level augmented reality three-dimensional map is designed. Those ... In response to the construction needs of “Real 3D China”, the system structure, functional framework, application direction and product form of block level augmented reality three-dimensional map is designed. Those provide references and ideas for the later large-scale production of augmented reality three-dimensional map. The augmented reality three-dimensional map is produced based on skyline software. Including the map browsing, measurement and analysis and so on, the basic function of three-dimensional map is realized. The special functional module including housing management, pipeline management and so on is developed combining the need of residential quarters development, that expands the application fields of augmented reality three-dimensional map. Those lay the groundwork for the application of augmented reality three-dimensional map. . 展开更多
关键词 Augmented Reality three-dimensional map Multi-Source Data Fusion three-dimensional Analysis three-dimensional Scene SKYLINE
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Application of Three-dimensional Laser Scanning Technology in the Teaching Practice of Surveying and Mapping of Ancient Buildings
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作者 Yapeng DUAN Junli LIU +2 位作者 Zhendong LIU Dingtao CAI Shaomin NI 《Asian Agricultural Research》 2019年第11期77-80,共4页
Based on the study of the application of three-dimensional laser scanning technology in ancient building surveying and mapping,this paper briefly describes the working principle and flow of three-dimensional laser sca... Based on the study of the application of three-dimensional laser scanning technology in ancient building surveying and mapping,this paper briefly describes the working principle and flow of three-dimensional laser scanning technology.Based on the practical application,this paper puts forward the discussion of related problems and matters needing attention.This has a certain reference significance for the study of new technology in surveying and mapping of ancient buildings. 展开更多
关键词 three-dimensional laser SCANNING technology SURVEYING and mapPING of ANCIENT BUILDINGS
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Numerical analysis of multicomponent responses of surface-hole transient electromagnetic method 被引量:3
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作者 孟庆鑫 胡祥云 +1 位作者 潘和平 周峰 《Applied Geophysics》 SCIE CSCD 2017年第1期175-186,192,共13页
We calculate the multicomponent responses of surface-hole transient electromagnetic method. The methods and models are unsuitable as geoelectric models of conductive surrounding rocks because they are based on regular... We calculate the multicomponent responses of surface-hole transient electromagnetic method. The methods and models are unsuitable as geoelectric models of conductive surrounding rocks because they are based on regular local targets. We also propose a calculation and analysis scheme based on numerical simulations of the subsurface transient electromagnetic fields. In the modeling of the electromagnetic fields, the forward modeling simulations are performed by using the finite-difference time-domain method and the discrete image method, which combines the Gaver–Stehfest inverse Laplace transform with the Prony method to solve the initial electromagnetic fields. The precision in the iterative computations is ensured by using the transmission boundary conditions. For the response analysis, we customize geoelectric models consisting of near-borehole targets and conductive wall rocks and implement forward modeling simulations. The observed electric fields are converted into induced electromotive force responses using multicomponent observation devices. By comparing the transient electric fields and multicomponent responses under different conditions, we suggest that the multicomponent-induced electromotive force responses are related to the horizontal and vertical gradient variations of the transient electric field at different times. The characteristics of the response are determined by the varying the subsurface transient electromagnetic fields, i.e., diffusion, attenuation and distortion, under different conditions as well as the electromagnetic fields at the observation positions. The calculation and analysis scheme of the response consider the surrounding rocks and the anomalous field of the local targets. It therefore can account for the geological data better than conventional transient field response analysis of local targets. 展开更多
关键词 Surface-hole transient electromagnetic method multicomponent response analysis transient electric field three-dimensional finite-difference time-domain method discrete image method
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Three-dimensional seismic isolation bearing and its application in long span hangars 被引量:13
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作者 Li Xiongyan Xue Suduo Cai Yancheng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第1期55-65,共11页
Based on the seismic response characteristics of space frame structures,a new type of seismic isolation bearing defined as a three-dimensional seismic isolation bearing(3DSIB) is developed in this paper.The bearing ... Based on the seismic response characteristics of space frame structures,a new type of seismic isolation bearing defined as a three-dimensional seismic isolation bearing(3DSIB) is developed in this paper.The bearing offers excellent properties such as multi-dimensional seismic isolation,reasonable rotation capability,good ability to resist lifting load,uncoupled stiffness in horizontal and vertical directions,etc.In the 3DSIB,the horizontal dimension is designed by combining the Teflon sliding device and helical spring,while the vertical dimension is developed by introducing disk springs or helical springs.The mathematical model of the 3DSIB was established and its performance with the critical parameters was tested on a shaking table.Furthermore,the 3DSIB was applied in a 120 m span hangar structure and simulated using SAP2000 software to evaluate its performance in practical structures.The performance of the structures with and without 3DSIB was compared.It is shown that the hangar structure with 3D bearings achieves a better performance.The axial force and acceleration response of the structures with 3DSIB are effectively reduced,while the displacement response of the bearing is within the predetermined range. 展开更多
关键词 three-dimensional seismic isolation bearing (3DSIB) seismic isolation HANGAR axial force acceleration response
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Science Letters:Dynamic concision for three-dimensional reconstruction of human organ built with virtual reality modelling language (VRML) 被引量:3
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作者 禹正杨 郑树森 +2 位作者 陈雷霆 何晓乾 王建军 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期611-616,共6页
This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize t... This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize the dynamic concision of 3D medical model with script node and sensor node in VRML. The 3D reconstruction and concision of body internal organs can be built with such high quality that they are better than those obtained from the traditional methods. With the function of dynamic concision, the VRML browser can offer better windows for man-computer interaction in real-time environment than ever before. 3D reconstruction and dynamic concision with VRML can be used to meet the requirement for the medical observation of 3D reconstruction and have a promising prospect in the fields of medical imaging. 展开更多
关键词 Virtual Reality Modelling Language (VRML) Direct texture mapping three-dimensional reconstruction Dynamic concision
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Strengthening the three-dimensional comprehensive observation system of multi-layer interaction on the Tibetan Plateau to cope with the warming and wetting trend 被引量:1
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作者 Yaoming Ma Binbin Wang +5 位作者 Xuelong Chen Lei Zhong Zeyong Hu Weiqiang Ma Cunbo Han Maoshan Li 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第4期67-71,共5页
Changes in the water cycle on the Tibetan Plateau(TP)have a significant impact on local agricultural production and livelihoods and its downstream regions.Against the background of widely reported warming and wetting,... Changes in the water cycle on the Tibetan Plateau(TP)have a significant impact on local agricultural production and livelihoods and its downstream regions.Against the background of widely reported warming and wetting,the hydrological cycle has accelerated and the likelihood of extreme weather events and natural disasters occurring(i.e.,snowstorms,floods,landslides,mudslides,and ice avalanches)has also intensified,especially in the highelevation mountainous regions.Thus,an accurate estimation of the intensity and variation of each component of the water cycle is an urgent scientific question for the assessment of plateau environmental changes.Following the transformation and movement of water between the atmosphere,biosphere and hydrosphere,the authors highlight the urgent need to strengthen the three-dimensional comprehensive observation system(including the eddy covariance system;planetary boundary layer tower;profile measurements of temperature,humidity,and wind by microwave radiometers,wind profiler,and radiosonde system;and cloud and precipitation radars)in the TP region and propose a practical implementation plan.The construction of such a three-dimensional observation system is expected to promote the study of environmental changes and natural hazards prevention. 展开更多
关键词 Plateau warming and wetting Hydrological cycle three-dimensional comprehensive observation system of multi-layer interaction Mountain-disaster response Tibetan Plateau
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Trends in Vegetation Response to Drought in Sudano-Sahelian Part of Northern Nigeria 被引量:1
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作者 Blessing Bolarinwa Fabeku Emmanuel C. Okogbue 《Atmospheric and Climate Sciences》 2014年第4期569-588,共20页
This study was carried out to evaluate the drought occurrence and its implication on vegetation cover over the Sudano-Sahelian zone of the Northern part of Nigeria. Monthly mean Rainfall data for the period 40 years (... This study was carried out to evaluate the drought occurrence and its implication on vegetation cover over the Sudano-Sahelian zone of the Northern part of Nigeria. Monthly mean Rainfall data for the period 40 years (1971-2010) were obtained from Nigeria Meteorological Agency (NIMET) for each of the meteorological stations present and functioning in this region for climatic analysis. Standardized Precipitation Index (SPI) was used to analyze drought occurrence on a time scale of five (5) months that cover the period of raining season over the study area. Also Satellite data over the selected part of the study area for three different epochs, 1986, 2000 and 2005 were used for vegetation response analysis. The SPI values were interpolated using Inverse Distance Weighted (IDW) interpolation technique in ArcGIS 9.3 to generate Drought Spatial Pattern Map for each selected modeled years. The vegetation response indicators used are land cover maps and Greenness Index (GI) maps. Land cover categories were classified into five levels: Dense Vegetation, less dense Vegetation, Settlement/built up, Bare Surface and Water body. The results based on the ground truth (rainfall) data show that many years of drought episode were experienced over the study area. On the other hand, the prime indicators (Land cover and GI maps) used in this study also depicts the changes that took place over the study area in response to this climatic anomaly (drought) and it could be noted that there was dramatic reduction in the occurrence towards the end of the last two decade, 1990-1999, which simply indicated improvement in rainfall even in 2000 and the later years. 展开更多
关键词 DROUGHT OCCURRENCE VEGETATION response Standardize PRECIPITATION INDEX (SPI) Normalized PRECIPITATION INDEX (NDVI) Greenness INDEX (GI) DROUGHT Spatial map
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