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Soil Geochemistry Changes Induced by a Foreign Soil Reconstruction Project in Three Gorges Reservoir Region of China 被引量:1
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作者 LIU Juan WEI Chao-Fu +1 位作者 LUO You-Jin DU Jing 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1511-1520,共10页
Fertile topsoil was added onto the surface of barren slope land in Three Gorges Reservoir region of China in an anthropogenic process known as the foreign soil reconstruction project. The main goal of this paper was t... Fertile topsoil was added onto the surface of barren slope land in Three Gorges Reservoir region of China in an anthropogenic process known as the foreign soil reconstruction project. The main goal of this paper was to reveal the influence of anthropogenic activities on pedogenic processes and soil classifications. Chemical weathering indices and comparative analysis were applied to discuss changes in geochemical compositions and weathering features of purplish soils(Cambisols) before and after the project. Results showed that:(1) The foreign soil reconstruction project slightly altered the major element composition of topsoil and improved the soil structure. Although the distributions of major elements in the original topsoil, original subsoil, foreign topsoil and newly constructed topsoil were all similar to that in upper continental crust, newly constructed topsoil was the most similar soil.(2) The chemical index of alteration was more sensitive than the weathering index of Parker at indicating chemical weathering status of purplish soil. The chemical weathering status of newly constructed topsoil was higher than that of the original topsoil and lower than that of foreign topsoil.(3) Anthropogenic activities may provide a promising new thought for the anthropogenic soil classification system. The scope and subgroups of Anthrosols should be extended and strengthened. Or there may be a need to combine Anthrosols and Technosols orders to create a new soil order. The results may be used for optimizing soil mellowing engineering activities and enriching the soil classification system. 展开更多
关键词 Anthropogenic activities Weathering status Foreign soil reconstruction project Pedogenic processes Three Gorges Reservoir region China
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Projects Lists Relating to Post-disaster Reconstruction
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《China's Foreign Trade》 2008年第23期61-66,共6页
Aba Prefecture Company Name:Sichuan Xintong New Materials Co.Ltd. Address:Shuimo,Wenchuan Nature of Business:Private Project Name:Processing and Sale of Tourism Products Details:Producing and processing of Natural cry... Aba Prefecture Company Name:Sichuan Xintong New Materials Co.Ltd. Address:Shuimo,Wenchuan Nature of Business:Private Project Name:Processing and Sale of Tourism Products Details:Producing and processing of Natural crystal products,man-made gem and other 展开更多
关键词 PDP COC LINE projects Lists Relating to Post-disaster reconstruction NATURE LED CO
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Study on Criterion of Differential Settlement in Subgrade Widening Project of an Expressway 被引量:1
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作者 胡江碧 张勇 费雪良 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期176-180,共5页
Criterion of differential settlement in subgrade is useful for keeping road in a good serving condition. The theory of traditional materials strength and their technologic economy are applied to analyze the additional... Criterion of differential settlement in subgrade is useful for keeping road in a good serving condition. The theory of traditional materials strength and their technologic economy are applied to analyze the additional bend stress of the pavement structure, the equivalent beam of elastic foundation and influence on the pavement structure of an uneven settlement. The allowable settling ratio of pavement index ( △i ) is got and is used to appraise the uneven settlement standard value in subgrade. The allowable settling ratio of pavement index is applied in an certain widening expressway project and △i ≤0.36 % is attained by the analyzing, calculating and adding a certain safe coefficient. This value was put into practice and is effective during the past two years. 展开更多
关键词 widening and reconstruction project differential settlement allowable settling ratio
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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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Discussion on the Safe and Guaranteed Access of Interchange Widening in Reconstruction and Extension of Highway
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作者 Heng Zhang Xuguang Zheng Jing Zhou 《Journal of Architectural Research and Development》 2021年第2期55-58,共4页
In the process of reconstruction and extension of highways,the most important thing is to ensure that the overall level of the widening of interchanges is comprehensively improved to ensure safe traffic.However,due to... In the process of reconstruction and extension of highways,the most important thing is to ensure that the overall level of the widening of interchanges is comprehensively improved to ensure safe traffic.However,due to the heavy and difficult tasks in the widening of interchanges,higher requirements are put forward for the construction quality of the project.In the actual construction of the project,it is necessary to actively analyze and explain the specific construction of the interchange widening project to ensure that the improvement level of the interchange widening in highway reconstruction and extension project is effectively upgraded.This paper gives a detailed introduction to the main construction technology for interchange widening project,clarifies the technical points of safety and guaranteed access,and proposes corresponding safeguard measures to ensure the comprehensive upgrade of the construction quality and standard of interchange widening in highway reconstruction and extension. 展开更多
关键词 Expressway reconstruction and extension project Widening of interchange Safety and guaranteed access
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基于重构主义的中国国际工程承包战略研究 被引量:3
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作者 陈天民 丁小迪 张雷 《工程管理学报》 2011年第5期477-481,共5页
为使中国国际工程承包商克服战略方面存在的劣势和问题,适应国际工程承包市场的发展需求,实现价值主张、利润主张和人员主张的合理匹配,将重构主义的战略观点引入中国国际工程承包的战略制定过程,并提出了相应的战略重构模型。战略重构... 为使中国国际工程承包商克服战略方面存在的劣势和问题,适应国际工程承包市场的发展需求,实现价值主张、利润主张和人员主张的合理匹配,将重构主义的战略观点引入中国国际工程承包的战略制定过程,并提出了相应的战略重构模型。战略重构模型表明中国承包商承接海外项目时可以同时追求差异化与低成本,开创新的市场空间,摆脱现有竞争,有助于中国国际工程承包业务实现高效益和持续性的发展。 展开更多
关键词 重构主义 中国国际工程承包 战略主张的匹配 战略重构模型
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A WEIGHTED ITERATIVE METHOD FOR ROBUST SELF-CALIBRATION
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作者 Liu Shigang Wu Chengke Tang Li Jia Jing 《Journal of Electronics(China)》 2006年第5期713-717,共5页
A robust self-calibration method is presented, which can efficiently discard the outliers based on a Weighted Iteration Method (WIM). The method is an iterative process in which the projective reconstruction is obtain... A robust self-calibration method is presented, which can efficiently discard the outliers based on a Weighted Iteration Method (WIM). The method is an iterative process in which the projective reconstruction is obtained based on the weights of all the points, whereas the weights are defined in inverse proportion to the re- ciprocal of the re-projective errors. The weights of outliers trend to zero after several iterations, and the accu- rate projective reconstruction is determined. The location of the absolute conic and the camera intrinsic pa- rameters are obtained after the projective reconstruction. The theory and experiments with both simulate and real data demonstrate that the proposed method is very efficient and robust. 展开更多
关键词 Weight iteration Self calibration projective reconstruction
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A 3D measurement method based on multi-view fringe projection by using a turntable 被引量:1
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作者 宋丽梅 高艳艳 +2 位作者 朱新军 郭庆华 习江涛 《Optoelectronics Letters》 EI 2016年第5期389-394,共6页
In order to get the entire data in the optical measurement, a multi-view three-dimensional(3D) measurement method based on turntable is proposed. In the method, a turntable is used to rotate the object and obtain mult... In order to get the entire data in the optical measurement, a multi-view three-dimensional(3D) measurement method based on turntable is proposed. In the method, a turntable is used to rotate the object and obtain multi-view point cloud data, and then multi-view point cloud data are registered and integrated into a 3D model. The measurement results are compared with that of the sticking marked point method. Experimental results show that the measurement process of the proposed method is simpler, and the scanning speed and accuracy are improved. 展开更多
关键词 projection registered cloud fringe calibration rotate fitting reconstructed coordinates scanner
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Geometric matrix research for nuclear waste drum tomographic gamma scanning transmission image reconstruction
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作者 张金钊 庹先国 《Chinese Physics C》 SCIE CAS CSCD 2015年第6期116-120,共5页
A geometric matrix model of nuclear waste drums is proposed for transmission image reconstruction from tomographic gamma scans(TGS). The model assumes that rays are conical, with intensity uniformly distributed with... A geometric matrix model of nuclear waste drums is proposed for transmission image reconstruction from tomographic gamma scans(TGS). The model assumes that rays are conical, with intensity uniformly distributed within the cone. The attenuation coefficients are centered on the voxel(cube) of the geometric center. The proposed model is verified using the EM algorithm and compared to previously reported models. The calculated results show that the model can obtain good reconstruction results even when the sample models are highly heterogeneous. 展开更多
关键词 tomographic verified cube reconstructed attenuation uniformly heterogeneous gamma projection uncertainty
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Development of projection-type optical scheme for computer-generated Fourier hologram recorder
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作者 E.Yu.Zlokazov S.B.Odinokov +1 位作者 N.M.Verenikina S.S.Donchenko 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第4期27-29,共3页
Projection-type recorders of computer-generated Fourier holograms have potential due to the decreased precision requirements of the optical scheme compared to most known holographic data recorders based on two-beam sc... Projection-type recorders of computer-generated Fourier holograms have potential due to the decreased precision requirements of the optical scheme compared to most known holographic data recorders based on two-beam schemes.In the case of optical memory system development,the reduction factor of the projection scheme requires the application of properly developed optical components.The present report is dedicated to the development of special objectives for the projection scheme of computer-generated Fourier holograms. 展开更多
关键词 projection holographic recording properly objectives simplicity match illumination dedicated reconstructed
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