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地方性克汀病患者掌纹A、D主线的观察 被引量:4
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作者 廖之升 樊乃驹 +6 位作者 黄河浪 姜梦璜 沈杰 姚呈祥 康俊才 刘壮生 漆冲春 《遗传》 CAS CSCD 北大核心 1990年第3期37-38,共2页
73例地克病人与对照组96例正常人的皮纹学A、D主线分布的比较观察结果表明,地克病人的A+D主线指数均值(7.07±1.42)低于正常人(7.83±1.40),差别非常显著(t<sub>A+D</sub>=3.47)。D主线较为显著(t<sub>D... 73例地克病人与对照组96例正常人的皮纹学A、D主线分布的比较观察结果表明,地克病人的A+D主线指数均值(7.07±1.42)低于正常人(7.83±1.40),差别非常显著(t<sub>A+D</sub>=3.47)。D主线较为显著(t<sub>D</sub>=3.05),男性病人的D主线终止于1—2区的比值(71.72%)显著高于正常人(χ<sup>2</sup>=41.98)。提示地克病人的皮纹发育异常,可能与先天发育不良和/或遗传因素有关。 展开更多
关键词 地方线 克汀病 皮纹学 A D主线
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The ridgelet transform with non-linear threshold for seismic noise attenuation in marine carbonates 被引量:5
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作者 张恒磊 宋双 刘天佑 《Applied Geophysics》 SCIE CSCD 2007年第4期271-275,共5页
Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coeffici... Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coefficients reveal only three spatial orientations. Whereas the ridgelet transform has a superior capability for direction detection and the ability to process signals with linearly changing characteristics. In this paper, we present the issue of low signal-to-noise ratio (SNR) seismic data processing based on the ridgelet transform. Actual seismic data with low SNR from south China has been processed using ridgelet transforms to improve the SNR and the continuity of seismic events. The results show that the ridgelet transform is better than the wavelet transform for these tasks. 展开更多
关键词 Ridgelet transform DENOISE marine strata south China non-linear threshold
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Three-dimensional interpretation of sparse survey line MT data: Synthetic examples 被引量:1
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作者 林昌洪 谭捍东 +2 位作者 舒晴 佟拓 张玉玫 《Applied Geophysics》 SCIE CSCD 2012年第1期9-18,114,共11页
Currently, most of MT (magnetotelluric) data are still collected on sparse survey lines and interpreted using 2D inversion methods because of the field work cost, the work area environment, and so on. However, there... Currently, most of MT (magnetotelluric) data are still collected on sparse survey lines and interpreted using 2D inversion methods because of the field work cost, the work area environment, and so on. However, there are some 2D interpretation limitations of the MT data from 3D geoelectrical structures which always leads to wrong geological interpretations. In this paper, we used the 3D inversion method to interpret the MT sparse lines data. In model testing, the sparse lines data are the MT full information data generated from a test model and processed using the 3D conjugate gradients inversion code. The inversion results show that this inversion method is reasonable and effective. Meanwhile, we prove that for inversion results with different element parameters, the results by joint inversion of both the impedance tensor data and the tipper data are more accurate and closer to the test model. 展开更多
关键词 MT sparse lines 3D inversion impedance tensor TIPPER
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An Image Encryption Approach Using a Shuffling Map 被引量:2
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作者 XIAO Yong-Liang XIA Li-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期876-880,共5页
A new image encryption approach is proposed.First,a sort transformation based on nonlinear chaoticalgorithm is used to shuffle the positions of image pixels.Then the states of hyper-chaos are used to change the greyva... A new image encryption approach is proposed.First,a sort transformation based on nonlinear chaoticalgorithm is used to shuffle the positions of image pixels.Then the states of hyper-chaos are used to change the greyvalues of the shuffled image according to the changed chaotic values of the same position between the above nonlinearchaotic sequence and the sorted chaotic sequence.The experimental results demonstrate that the image encryptionscheme based on a shuffling map shows advantages of large key space and high-level security.Compared with someencryption algorithms,the suggested encryption scheme is more secure. 展开更多
关键词 IMAGE ENCRYPTION hyper-chaotic SHUFFLING SORT
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Application of Seismic Inversion Using Logging Data as Constraints in Coalfield 被引量:3
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作者 许永忠 潘冬明 +1 位作者 张宝水 崔若飞 《Journal of China University of Mining and Technology》 2004年第1期22-25,共4页
Seismic inversion and basic theory are briefly presented and the main idea of this method is introduced. Both non-linear wave equation inversion technique and Complete Utilization of Samples Information (CUSI) neural ... Seismic inversion and basic theory are briefly presented and the main idea of this method is introduced. Both non-linear wave equation inversion technique and Complete Utilization of Samples Information (CUSI) neural network analysis are used in lithological interpretation in Jibei coal field. The prediction results indicate that this method can provide reliable data for thin coal exploitation and promising area evaluation. 展开更多
关键词 seismic data inversion CUSI neural network wave impedance logging data thin coal seams
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A Method for Generating Contour Tree Based on Voronoi Interior Adjacency
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作者 QIAO Chaofei ZHAO Renliang +1 位作者 CHEN Jun CHEN Yunhao 《Geo-Spatial Information Science》 2005年第4期287-290,310,共5页
A contour tree is a good graphical tool for representing the spatial relations of contour lines and has many applications in map generalization, map annotation, terrain analysis, etc. A new method for generating conto... A contour tree is a good graphical tool for representing the spatial relations of contour lines and has many applications in map generalization, map annotation, terrain analysis, etc. A new method for generating contour trees by introducing a Voronoi based interior adjacency concept is proposed in this paper. The immediate interior adjacency set is employed to identify all of the children contours of each contour without contour elevations. It has advantages over existing methods such as the geometric method and the region growing based method. 展开更多
关键词 spatial relations of contour lines contour tree Voronoi interior adjacency set
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The Impacts of Permafrost Change on NPP and Implications:A Case of the Source Regions of Yangtze and Yellow Rivers 被引量:9
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作者 FANG Yiping QIN Dahe +2 位作者 DING Yongjian YANG Jianping XU Keyan 《Journal of Mountain Science》 SCIE CSCD 2011年第3期437-447,共11页
This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolatin... This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolating functions,and non-linear regression methods.The source regions of the Yangtze and Yellow Rivers were selected as the research areas.Results illustrate that:(1) There is significant non-linear relationship between NPP and GT in various typical years;(2) The maximum value of NPP is 6.17,5.87,7.73,and 5.41 DM·t·hm-2 ·a-1 respectively,and the corresponding GT is 7.1,10.0,21.2,and 8.9 o C respectively in 1980,1990,2000 and 2007;(3) In 1980,the sensitivity of NPP to GT is higher than in 1990,2000 and 2007.This tendency shows that the NPP presents change from fluctuation to an adaptation process over time;(4) During 1980~2007,the accumulated NPP was reduced to 8.05,and the corresponding carrying capacity of theoretical livestock reduced by 11%;(5) The shape of the demonstration region of ecological compensation system,livelihood support system,and science appraisal system in the source regions of Yangtze and Yellow Rivers are an important research for increasing the adaptation capacity and balancing protection and development. 展开更多
关键词 The source regions of Yangtze and Yellow Rivers PERMAFROST Ground temperature (GT) Net primary productivity (NPP) Policy adaptation
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Impacts of Climatic Change on River Runoff in Northern Xinjiang of China over Last Fifty Years 被引量:6
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作者 YANG Yuhui CHEN Yaning +2 位作者 LI Weihong WANG Minzhong SUN Guili 《Chinese Geographical Science》 SCIE CSCD 2010年第3期193-201,共9页
The characteristics of climatic change and fiver runoff, as well as the response of fiver runoff to climatic change in the northern Xinjiang are analyzed on the basis of the hydrological and meteorological data over t... The characteristics of climatic change and fiver runoff, as well as the response of fiver runoff to climatic change in the northern Xinjiang are analyzed on the basis of the hydrological and meteorological data over the last 50 years by the methods of Mann-Kendall nonparametric test and the nonlinear regression model. The results show that: 1) The temperature and the precipitation increased significantly in the whole northern Xinjiang, but the precipitation displayed no obvious change, or even a decreasing trend in the northern mountainous area of the northern Xinjiang. 2) River runoff varied in different regions in the northern Xinjiang. It significantly increased in the northern slope of the Tianshan Mountains and the north of the northern Xinjiang (p = 0.05), while slightly ificreased in the west of the northern Xinjiang. 3) North Atlantic Oscillation (NAO) affects fiver runoff by influencing temperature and precipitation. The NAO and precipitation had apparent significant correlations with the fiver runoff, but the temperature did not in the northern Xinjiang. Since the mid-1990s fiver runoff increase was mainly caused by the increasing temperature in the northern slope of the Tianshan Mountains and the north of the northern Xinjiang. Increased precipitation resulted in increased fiver runoff in the west of the northern Xinjiang. 展开更多
关键词 climatic change river runoff Mann-Kendall test nonlinear regression model NAO northern Xinjiang
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Wave Motion of Smoke in Subway Fire Environment 被引量:1
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作者 吴文忠 由世俊 《Transactions of Tianjin University》 EI CAS 2009年第3期206-209,共4页
Wave motion in subway or tunnel fire is an intrinsic property of smoke.As the pressure of smoke changes with mass of certain power,a kind of linear wave equation for smoke can be derived from the conservation equation... Wave motion in subway or tunnel fire is an intrinsic property of smoke.As the pressure of smoke changes with mass of certain power,a kind of linear wave equation for smoke can be derived from the conservation equations of its mass and momentum,under nearly homogeneous zone assumption.The smoke movement of 4 subway fires was simulated with Airpak.By fitting the pressure-mass functions to the simulated data,wave equations of the smoke were derived,and wave motions of smoke were thus validated.It can be seen that smoke wave is a kind of mass wave,whose velocity is inversely proportional to smoke mass,and wave of a bigger fire propagates slower. 展开更多
关键词 subway fire environment smoke movement wave propagation
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Generating and AnalyzingN-di mensional Hilbert Cell
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作者 FENG Yucai LI Chenyang 《Geo-Spatial Information Science》 2005年第4期297-305,共9页
In this paper, two algorithms are presented for generating two code scan lists of an N dimensional Hilbert cell, and a formal proof of the backward encoding algorithm is given. On the basis of the self similarity prop... In this paper, two algorithms are presented for generating two code scan lists of an N dimensional Hilbert cell, and a formal proof of the backward encoding algorithm is given. On the basis of the self similarity properties of a Hilbert curve, this paper gives a novel algorithm for generating a static evolvement rule table through analyzing a Hilbert cell. By looking up the static evolvement rule table, the N dimensional Hilbert mappings are efficiently implemented. 展开更多
关键词 ALGORITHM Hilbert curve space-filling curve
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Application of DC component to select fault branch in arc suppression coil grounding system 被引量:2
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作者 Zhi-Jie WANG Yan-Wen WANG 《Journal of Coal Science & Engineering(China)》 2013年第3期396-401,共6页
When single phase earth fault occurs in the arc suppression coil grounding system, the amplitude of the transient capacitance current is high and decays fast, but the attenuation of the transient inductance current is... When single phase earth fault occurs in the arc suppression coil grounding system, the amplitude of the transient capacitance current is high and decays fast, but the attenuation of the transient inductance current is much slower. This paper analyses the DC component of fault branch, and has found it is much bigger than that of the normal branches in transient state. All the simulation results obtained from three compensation types, different fault time and different wave cycles show that the DC component of fault branch is much higher than that of those normal branches. These results verify the effectiveness of taking the DC component as the method of fault line selection in the arc suppression coil grounding system. 展开更多
关键词 DC component arc suppression coil fault line selection transient state
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Specificity and Semantic Horizon of the Human Sciences from the Viewpoint of Bakhtin's Metalinguistics
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作者 Olga Ruptash 《Journal of Philosophy Study》 2013年第7期559-568,共10页
This article explores the potential resources of the Bakhtin's theory of dialogism and its core concepts for the development of the philosophy and methodology of the human sciences. Focusing on Bakhtin's late essays... This article explores the potential resources of the Bakhtin's theory of dialogism and its core concepts for the development of the philosophy and methodology of the human sciences. Focusing on Bakhtin's late essays: "The Problem of the Text in Linguistics, Philology, and the Human Sciences; From Notes Made in 1970-71;" and "Toward a Methodology for the Human Sciences," the author deals with such concepts as sense, semantic whole, superaddressee, the third, and outsideness. Metalinguistics is interpreted as a philosophical approach to the problems of humanities methodology. The specifics of the human sciences, which Bakhtin put to the question, are described in comparison and correlation with the natural sciences. The author elaborates the idea of the communicative three-part relationship or trilogue (as a development of the dialogue). The role of the superaddressee as the third participant of the trilogue between the researcher (the subject) and the text (the object) is discussed. The notion semantic whole and its implementation in the process of the sense's becoming (development) are analyzed. 展开更多
关键词 DIALOGUE text sense semantic whole the human sciences
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Scattering of Plane P Waves by Circular-arc Canyon Topography:High-frequency Solution
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作者 Yang Caihong 《Earthquake Research in China》 2010年第2期155-166,共12页
Through the Fourier-Bessel series expansion of wave functions,the analytical solution to the two-dimensional scattering problem of incidental plane P waves by circular-arc canyon topography with different depth-to-wid... Through the Fourier-Bessel series expansion of wave functions,the analytical solution to the two-dimensional scattering problem of incidental plane P waves by circular-arc canyon topography with different depth-to-width ratio is deduced.Unlike other existing analytical solutions,in order to ensure that the analytical solution is valid for higher frequency incident waves,the asymptotic properties of cylindrical functions are in this paper introduced to directly determine the unknown coefficients of scattering waves,avoiding the solution of linear equation systems and corresponding numerical issues,which in turn expand the frequency band in which the analytical solution is valid.Comparison with other existing analytical solutions demonstrates that the proposed analytical solution is correct.Furthermore,the scattering effects of a circular-arc canyon on the incident plane P wave are analyzed in a comparatively broad frequency band. 展开更多
关键词 Plane P wave Canyon topography SCATTERING Analytical solution Site effect
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Determination of photosynthetic parameters in two seawater-tolerant vegetables 被引量:1
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作者 邱念伟 周峰 +1 位作者 刘倩 赵文倩 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第2期412-415,共4页
It is difficult to determine the photosynthetic parameters of non-fiat leaves/green stems using photosynthetic instruments, due to the unusual morphology of both organs, especially for Suaeda salsa and Salicornia bige... It is difficult to determine the photosynthetic parameters of non-fiat leaves/green stems using photosynthetic instruments, due to the unusual morphology of both organs, especially for Suaeda salsa and Salicornia bigelovii as two seawater-tolerant vegetables. To solve the problem, we developed a simple, practical, and effective method to measure and calculate the photosynthetic parameters (such as PN, gs, E) based on unit fresh mass, instead of leaf area. The light/COftemperature response curves of the plants can also be measured by this method. This new method is more effective, stable, and reliable than conventional methods for plants with non-flat leaves. In addition, the relative notes on measurements and calculation of photosynthetic parameters were discussed in this paper. This method solves technical difficulties in photosynthetic parameter determination of the two seawater-tolerant vegetables and similar plants. 展开更多
关键词 photosynthetic parameters non-flat leaf fresh mass seawater-tolerant vegetable
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Application of Interval Newton Method to Solve Nonlinear Equations and Global Optimization
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作者 LI Shuang XU Caijun WANG Xinzhou 《Geo-Spatial Information Science》 2003年第1期24-27,33,共5页
The basic principle of interval arithmetic and the basic algorithm of the interval Newton methods are introduced.The prototype algorithm can not find any zero in an interval that has zero sometimes,that is,it is insta... The basic principle of interval arithmetic and the basic algorithm of the interval Newton methods are introduced.The prototype algorithm can not find any zero in an interval that has zero sometimes,that is,it is instable.So the prototype relaxation procedure is improved in this paper.Additionally,an immediate test of the existence of a solution following branch_and_bound is proposed,which avoids unwanted computations in those intervals that have no solution.The numerical results demonstrat that the improved interval Newton method is superior to prototype algorithm in terms of solution quality,stability and convergent speed. 展开更多
关键词 interval algorithm interval Newton method global optimization
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Bicharacteristic Curves in Modeling of the Earth Crust and Upper Mantle
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作者 Georgi Boyadzhiev 《Journal of Mathematics and System Science》 2014年第3期167-172,共6页
The aim of this paper is the introduction of a new approach to 3D modelling of elastic piecewise homogeneous media, in particular Earth crust and upper Mantle. The method is based on the principle of tomography with E... The aim of this paper is the introduction of a new approach to 3D modelling of elastic piecewise homogeneous media, in particular Earth crust and upper Mantle. The method is based on the principle of tomography with Earthquake as a source of the signal and receiver stations on the surface. The wave propagation in solid media is described by a system of three strongly coupled hyperbolic equations with piece - wise constant coefitients. The characteristic set and hi-characteristic curves of this system are computed in a homogeneous half-space with free boundary and the formulae of reflection and diffraction of the hi-characteristics on the internal boundaries of the media. Applications of the characteristic set and bi-eharacteristic curves for the inverse problem in geophysics and Earth modelling are given. 展开更多
关键词 3D modeling of Lithosphere BICHARACTERISTICS strongly coupled linear systems of PDE
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Study on mine earthquake activity rules for Laohutai coal mine in Fushun of Liaoning 被引量:2
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作者 HAN Xiaomin CHEN Li SUN Wenda 《Global Geology》 2011年第2期102-105,共4页
According to earthquake data of Fushun earthquake administration,the seismic analysis and statistical methods are utilized in order to analyze earthquake frequency,"b"-value timing and energy creep trends in... According to earthquake data of Fushun earthquake administration,the seismic analysis and statistical methods are utilized in order to analyze earthquake frequency,"b"-value timing and energy creep trends in Laohutai coal mine. By using least squares linear regression method,the relational expression between frequency and magnitude of mine earthquake in Laohutai coal mine is given. And the possible largest magnitude mine earthquake inferred has also been calculated. And this paper also provides a theoretical basis for further study of mine earthquake activity. 展开更多
关键词 mine earthquake earthquake frequency energy creep curve "b"-value method magnitude prediction
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Signal Path Reckoning Localization Method in Multipath Environment 被引量:5
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作者 Junhui Zhao Lei Li +1 位作者 Hao Zhang Yi Gong 《China Communications》 SCIE CSCD 2017年第3期182-189,共8页
In the wireless localization application, multipath propagation seriously affects the localization accuracy. This paper presents two algorithms to solve the multipath problem. Firstly, we improve the Line of Possible ... In the wireless localization application, multipath propagation seriously affects the localization accuracy. This paper presents two algorithms to solve the multipath problem. Firstly, we improve the Line of Possible Mobile Device(LPMD) algorithm by optimizing the utilization of the direct paths for single-bound scattering scenario. Secondly, the signal path reckoning method with the assistance of geographic information system is proposed to solve the problem of localization with multi-bound scattering paths. With the building model's idealization, the proposed method refers to the idea of ray tracing and dead reckoning. According to the rule of wireless signal reflection, the signal propagation path is reckoned using the measurements of emission angle and propagation distance, and then the estimated location can be obtained. Simulation shows that the proposed method obtains better results than the existing geometric localization methods in multipath environment when the angle error is controlled. 展开更多
关键词 wireless localization multipath propagation signal reflection path reckoning
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Artificial Neural Network Model of Hydrocarbon Migration and Accumulation
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作者 刘海滨 吴冲龙 《Journal of China University of Mining and Technology》 2002年第2期210-214,共5页
Based on the dynamic simulation of the 3 D structure the sedimentary modeling, the unit entity model has been adopted to transfer the heterogeneous complex passage system into limited simple homogeneous entity, and th... Based on the dynamic simulation of the 3 D structure the sedimentary modeling, the unit entity model has been adopted to transfer the heterogeneous complex passage system into limited simple homogeneous entity, and then the traditional dynamic simulation has been used to calculate the phase and the drive forces of the hydrocarbon , and the artificial neural network(ANN) technology has been applied to resolve such problems as the direction, velocity and quantity of the hydrocarbon migration among the unit entities. Through simulating of petroleum migration and accumulation in Zhu Ⅲ depression, the complex mechanism of hydrocarbon migration and accumulation has been opened out. 展开更多
关键词 hydrocarbon migration and accumulation nonlinear course ANN
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Discussion on bearing capacity of soft rock ground based on in-situ load test
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作者 Gao Wenhua Zhu Jianqun Huang Ziyong Liu Dong 《Engineering Sciences》 EI 2010年第4期37-41,共5页
The suitability of five methods was discussed here,taking the typical results from in-situ load test of Renshou Mansion and Caifu Plaza in Yueyang City for example.It shows that bearing capacity can be obtained by the... The suitability of five methods was discussed here,taking the typical results from in-situ load test of Renshou Mansion and Caifu Plaza in Yueyang City for example.It shows that bearing capacity can be obtained by the proportion load and limit load from p-s curve with the first and the second point of contraflexure easily.It is recommended that the accurate value of bearing capacity can be obtained by hyperbola fitting method and minimum curvature radius method theoretically.The rebound method is clear in principle,in which the elastoplasticity characteristic is thought about.Out of consideration for the unsteadiness and unobviousness of bearing capacity from relative settlement method,it can be only adopted as reference.So bearing capacity of soft rock ground should be determined by weathering condition of soft rock and curve type. 展开更多
关键词 rock mechanics soft rock bearing capacity of ground in-situ load test of rock ground characteristic curve
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