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Ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District
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作者 Gong Hongsheng Han Runsheng +2 位作者 Li Ziteng Ren Tao Wang Jiasheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期202-203,共2页
1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is ... 1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is strictly controlled by fault structures.It has developed to one of the famous production bases of lead&zinc and germanium in China. 展开更多
关键词 PB ore-controlling regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District Zn
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The Characteristics of Ore-Controlling Structure in Baoshan Cu-Pb-Zn Polymetallic Deposit,Hunan Province 被引量:3
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作者 QI Fan-yu1,ZHANG Zhi1,2,LI Yong-sheng1,ZHEN Shi-min1,JIA De-long1,GONG Fan-ying1,GONG Xiao-dong1,HE Peng1(1.School of Earth & Resources,China University of Geosciences Beijing,Beijing 100083,China 2.Development and Research Center,Beijing 100037 China) 《矿物学报》 CAS CSCD 北大核心 2011年第S1期823-824,共2页
The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part ... The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part of Nanling polymetallic deposit belt.The outcropping stratas consist of upper Devonian Shetianqiao,Xikuangshan Formation,Lower Carboniferous Menggong’ao,Shidengzi,Ceshui,and Zimenqiao Formation.Igneous rocks in the Baoshan ore area mainly comprise granodiorite porphyry.Furthermore,the radio isotopic age ranges from 123 Ma to 183 Ma,belonging to the early to middle Yanshanian. 展开更多
关键词 PB The Characteristics of ore-controlling structure in Baoshan Cu-Pb-Zn Polymetallic Deposit Hunan Province ZN CU
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Analysis of Ore-controlling Structure in the Qifengcha-Detiangou Gold Deposit,Huairou County,Beijing 被引量:1
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作者 CHEN Bailin LI Zhongjian DONG Faxian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第1期94-100,共7页
The Qifengcha-Detiangou gold deposit is a medium-sized deposit recently found in Huairou County, Beijing. It belongs to the altered mylonite type with superimposed quartz vein type and is related to the early Yanshani... The Qifengcha-Detiangou gold deposit is a medium-sized deposit recently found in Huairou County, Beijing. It belongs to the altered mylonite type with superimposed quartz vein type and is related to the early Yanshanian magmatic activity. Characterized by multiperiodic activity, the NE-trending Qifengcha fault is a regional ore-controlling structure in the area, and gold mineralization develops only in its southeastern part. Meanwhile, gold mineralization is controlled by the Yunmengshan metamorphic core complex. The nearly N-S- and E-W-trending low-angle detachment faults, reformed by the Qifengcha fault in the northwestern part of the core complex, are the main ore-bearing faults. All discovered gold deposits are located within an area 1.5–4.0 km away from the boundary of the upwelling centre. The N-S- (NNE-) and E-W-trending ore-bearing faults are ductile-brittle structural zones developing in shallow positions and subjected mainly to compressive deformation. The structural ore-controlling effects are as follows. (1) The attitude, shape, and distribution of gold orebodies are controlled by faults. (2) There is a negative correlation between the gold abundance and the magnetic anisotropy (P) of the altered mylonite samples from the deposit, which shows that the gold mineralization is later than the structural deformation. (3) Quartz vein type mineralization is superimposed on altered mylonite type mineralization. (4) In mineralized mylonite, the stronger the ductile shear deformation, the easier the late-stage gold mineralization to occur and the higher the gold abundance. The richest gold mineralization occurs only around the centre of the fault subjected to the strongest deformation. 展开更多
关键词 analysis of ore-controlling structure Qifengcha-Detiangou gold deposit BEIJING
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Analysis of Ore-Controlling Structures of the Xincheng-Hexi Gold Deposit,Shandong Province,China
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作者 LEI Shibin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期548-553,共6页
Based on quantitative and semi-quantitative mathematical and mechanical analysis of the shape, motion, structural factors, stress field and deformation field of the ore-hosting faults in the Xincheng-Hexi gold deposit... Based on quantitative and semi-quantitative mathematical and mechanical analysis of the shape, motion, structural factors, stress field and deformation field of the ore-hosting faults in the Xincheng-Hexi gold deposit, the ore-controlling features of faults and mineralization mechanism are discussed. It is concluded that the mineralization is controlled by the main faults, subsidiary fractures, joint density, mechanical features and deformation of the faults. The ore bodies are mainly located in the lower part of the convex crest and upper part of the concave trough of the main undulating fault surface. Mineralization is positively correlated to the development of subsidiary fractures and joints, which correspond to zones of low internal stress and high body strain and shear strain. They are favourable positions for mineralization and alteration. 展开更多
关键词 SHANDONG gold deposit ore-controlling structure
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GEOCHEMICAL REASERCH ON ORE-CONTROLLING STRUCTURE IN LIAODONG LUOQUANBEI-BAIYUN GOLD MINERAL BELT
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作者 LI Pei zheng, TIAN Shu hai, WANG Qian cheng (College of Resource, Environment and Civil Engeneering, Central South University, Changsha 410083, China) 《Geotectonica et Metallogenia》 2001年第1期159-161,共3页
In recent2 0 years,because of the finding ofmany large- superlargegold deposits,we re- new the theories for prospecting and gain many things and conceptions.The current geo- chemical and gold- forming theories underli... In recent2 0 years,because of the finding ofmany large- superlargegold deposits,we re- new the theories for prospecting and gain many things and conceptions.The current geo- chemical and gold- forming theories underline the importance of the early submarine volcano- sedimentation,metamorphic differention,sedimentation of terrigenous clastics,thermal spring and it’s sedimentation,syngenesis process and other hypergene supplying the source for metallogenic materials.According to the study for source bed(rock) and depsitional for- mation of gold,we find that gold will be gradually enriched and mineralized in source bed (rock) ,because of variousgeologicprocesses,such as regional metamorphism ormigmatiza- tion,geothermal bittern,volcanism. The ore- control of deep and giant fault and ductile shear beltand tectono- flash space is emphasized,especially,we should notice the long- term, succession and multistage of the 展开更多
关键词 rock SE GEOCHEMICAL REASERCH ON ore-controlling structure IN LIAODONG LUOQUANBEI-BAIYUN GOLD MINERAL BELT ORE
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INDUCTION—POLYMERIZATION OF PREPARING POLYMERS OF REGULAR STRUCTURE
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作者 Hsiao Lin CHANG, You An Map, Yi Men CHENG Department of Materials Science and Applied Chemistry, National University of Defence Technology, Changsha, 410073 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期821-822,共2页
Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points... Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points and polymerized to polymer of regular structure. Regularity of structure of the polyacrylamide prepared by this means has been verified with electron diffractograms, DSC curve and IR spectrum of the polymer. 展开更多
关键词 TEM INDUCTION POLYMERIZATION OF PREPARING POLYMERS OF regular structure
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Modeling of 3D-structure for regular fragments of low similarity unknown structure proteins
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作者 彭志红 Chen Jie Lin Xiwen Sang Yanchao 《High Technology Letters》 EI CAS 2007年第4期431-435,共5页
Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular ... Because it is hard to search similar structure for low similarity unknown structure proteins directly from the Protein Data Bank (PDB) database, 3D-structure is modeled in this paper for secondary structure regular fragments (α-Helices, β-Strands) of such proteins by the protein secondary structure prediction software, the Basic Local Alignment Search Tool (BLAST) and the side chain construction software SCWRL3. First, the protein secondary structure prediction software is adopted to extract secondary structure fragments from the unknown structure proteins. Then, regular fragments are regulated by BLAST based on comparative modeling, providing main chain configurations. Finally, SCWRL3 is applied to assemble side chains for regular fragments, so that 3D-structure of regular fragments of low similarity unknown structure protein is obtained. Regular fragments of several neurotoxins are used for test. Simulation results show that the prediction errors are less than 0.06nm for regular fragments less than 10 amino acids, implying the simpleness and effectiveness of the proposed method. 展开更多
关键词 low similarity unknown structure regular segment 3D-structure modeling main chain confonnation side chain assembly
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Data-Path Placement Based on Regularity Extraction and Implementation
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作者 杨长旗 洪先龙 +2 位作者 蔡懿慈 经彤 吴为民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第8期925-936,共12页
An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal ... An algorithm named DPP is addressed.In it,a new model based on the concept of irregularity degree is founded to evaluate the regularity of cells.It generates the structure regularity of cells by exploiting the signal flow of circuit.Then,it converts the bit slice structure to parallel constraints to enable Q place algorithm.The design flow and the main algorithms are introduced.Finally,the satisfied experimental result of the tool compared with the Cadence placement tool SE is discussed. 展开更多
关键词 Data Path regularity extraction bit slice structure Q place
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MPS-FEM Coupled Method for Study of Wave-Structure Interaction 被引量:3
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作者 Guanyu Zhang Xiang Chen Decheng Wan 《Journal of Marine Science and Application》 CSCD 2019年第4期387-399,共13页
Nowadays,an increasing number of ships and marine structures are manufactured and inevitably operated in rough sea.As a result,some phenomena related to the violent fluid-elastic structure interactions(e.g.,hydrodynam... Nowadays,an increasing number of ships and marine structures are manufactured and inevitably operated in rough sea.As a result,some phenomena related to the violent fluid-elastic structure interactions(e.g.,hydrodynamic slamming on marine vessels,tsunami impact on onshore structures,and sloshing in liquid containers)have aroused huge challenges to ocean engineering fields.In this paper,the moving particle semi-implicit(MPS)method and finite element method(FEM)coupled method is proposed for use in numerical investigations of the interaction between a regular wave and a horizontal suspended structure.The fluid domain calculated by the MPS method is dispersed into fluid particles,and the structure domain solved by the FEM method is dispersed into beam elements.The generation of the 2D regular wave is firstly conducted,and convergence verification is performed to determine appropriate particle spacing for the simulation.Next,the regular wave interacting with a rigid structure is initially performed and verified through the comparison with the laboratory experiments.By verification,the MPS-FEM coupled method can be applied to fluid-structure interaction(FSI)problems with waves.On this basis,taking the flexibility of structure into consideration,the elastic dynamic response of the structure subjected to the wave slamming is investigated,including the evolutions of the free surface,the variation of the wave impact pressures,the velocity distribution,and the structural deformation response.By comparison with the rigid case,the effects of the structural flexibility on wave-elastic structure interaction can be obtained. 展开更多
关键词 MPS-FEM coupled method Fluid-structure interaction(FSI) regular wave Wave impact pressure structure deformation response
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Occurrence characteristics and enrichment regularity of indium in pyrite: A case study of Dachang tin ore-field 被引量:2
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作者 Yong-sheng CHENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第8期2197-2208,共12页
To reveal the occurrence state and enrichment regularity of the dispersed element indium in pyrite, the petrology,mineralogy, geochemistry, and mineral physics were researched detailedly. The results suggest that the ... To reveal the occurrence state and enrichment regularity of the dispersed element indium in pyrite, the petrology,mineralogy, geochemistry, and mineral physics were researched detailedly. The results suggest that the structure of pyrite is mainlycomposed of massive structure, disseminated structure, vein structure, reticular structure, comb structure and so on. Generally, thepyrite coexists with sphalerite, marmatite, pyrrhotite, chalcopyrite, galena, and arsenopyrite. And the texture of pyrite primarilyconsists of the metasomatic texture, solid solution texture, idiomorphic?hypidiomorphic granular texture, and disseminated texture.The content of indium in pyrite ranges from 0.491×10?6 to 65.1×10?6 with an average value of 14.38×10?6. Yet, the indium content inthe Gaofeng deposit is higher than that in the Dafulou and Tongkeng deposit, showing a particularly significant supernormalenrichment. Besides, the cadmium content in pyrite is also higher than other dispersed elements, and similarly the abnormalenrichment of cadmium in the Gaofeng deposit is also very significant. An obvious positive correlation exists between In and Cd, orTl, but a negative correlation between In and Re. It is difficult to find out a positive or negative correlation between In and Ga. Theelement zinc is of great importance to the enrichment of indium, which can possibly facilitate to the migration and crystallization of dispersed element indium. 展开更多
关键词 dispersed element indium PYRITE lattice structure enrichment regularity cassiterite-sulfide deposit Dachang ore-field
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Mineralization and Ore-controlling Implications of Low-angle Faults 被引量:1
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作者 CHEN Bailin LIU Jianmin +1 位作者 ZHANG Da WU Jianshe 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第4期438-446,共9页
Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own par... Abstract Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own particularities. The low-angle fault plays an important role in controlling over some endogenetic metallic ore deposits. Based on studies of the Xiaoban gold deposit, Xinzhou gold deposit, and Longfengchang polymetallic ore deposit, and comparisons with other mines, the authors conclude the ore-controlling implications of low-angle faults as follows. (1) Because of high temperature and high pressure, as well as strong ductile deformation, the internal energy of the elements rises in the large-scale deep ductile low-angle faults, which causes the elements to activate and differentiate from the source rocks, forming ore-bearing hydrothermal solution, and bring mineralization to happen. (2) When rising from depths and flowing along the low-angle faults, the ore-bearing hydrothermal solution will alter and replace the tectonites in the fault zone. The rocks of the hanging side and the heading side differ in lithology, texture and structure, which results in changes or dissimilarities of the physical-chemical conditions. This destroys the balance of the hydrothermal solution system and causes the dissolved ore-forming elements to precipitate; as a result, a deposit is formed. Therefore, the meso-shallow ductile-brittle low-angle faults play the role of a geochemical interface in the process of mineralization. (3) Low-angle faults are often one of the important host structures. 展开更多
关键词 low-angle fault ore-controlling structure structural metallogenesis geochemical interface of mineralization host structure
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Inverse Load Identification in Stiffened Plate Structure Based on in situ Strain Measurement 被引量:1
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作者 Yihua Wang Zhenhuan Zhou +2 位作者 Hao Xu Shuai Li Zhanjun Wu 《Structural Durability & Health Monitoring》 EI 2021年第2期85-101,共17页
For practical engineering structures,it is usually difficult to measure external load distribution in a direct manner,which makes inverse load identification important.Specifically,load identification is a typical inv... For practical engineering structures,it is usually difficult to measure external load distribution in a direct manner,which makes inverse load identification important.Specifically,load identification is a typical inverse problem,for which the models(e.g.,response matrix)are often ill-posed,resulting in degraded accuracy and impaired noise immunity of load identification.This study aims at identifying external loads in a stiffened plate structure,through comparing the effectiveness of different methods for parameter selection in regulation problems,including the Generalized Cross Validation(GCV)method,the Ordinary Cross Validation method and the truncated singular value decomposition method.With demonstrated high accuracy,the GCV method is used to identify concentrated loads in three different directions(e.g.,vertical,lateral and longitudinal)exerted on a stiffened plate.The results show that the GCV method is able to effectively identify multi-source static loads,with relative errors less than 5%.Moreover,under the situation of swept frequency excitation,when the excitation frequency is near the natural frequency of the structure,the GCV method can achieve much higher accuracy compared with direct inversion.At other excitation frequencies,the average recognition error of the GCV method load identification less than 10%. 展开更多
关键词 structural health monitoring load identification Tikhonov regularization generalized cross validation stiffened plate structure
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Analysis on geological structures influencing gas occurrence at Qidong coalmine 被引量:1
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作者 WU Shi-yong HU Bao-lin YAO Duo-xi ZHANG De-sheng 《Journal of Coal Science & Engineering(China)》 2010年第3期292-295,共4页
The occurrence state of methane is mostly controlled by coalfield geologicalstructures.The coal-bearing strata at Qidong coalmine experienced many tectonic cyclessince their formation.The gas content made by the compl... The occurrence state of methane is mostly controlled by coalfield geologicalstructures.The coal-bearing strata at Qidong coalmine experienced many tectonic cyclessince their formation.The gas content made by the complicated structural geologic systemat the coalfield is very different, which is obviously higher on the north side of the Weimiaofracture belt than that on the south side and near itself.This thesis discussed the gas occurrenceregularity based on the geometric characteristics of the geological structure andits regional tectonic evolution.This study can provide a foundation for coalfield exploitationand deal with coal and gas outburst. 展开更多
关键词 geological structure evolutional regularity gas occurrence Qidong coalmine
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RGBD Salient Object Detection by Structured Low-Rank Matrix Recovery and Laplacian Constraint 被引量:1
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作者 Chang Tang Chunping Hou 《Transactions of Tianjin University》 EI CAS 2017年第2期176-183,共8页
A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the s... A structured low-rank matrix recovery model for RGBD salient object detection is proposed. Firstly, the problem is described by a low-rank matrix recovery, and the hierarchical structure of RGB image is added to the sparsity term. Secondly, the depth information is fused into the model by a Laplacian regularization term to ensure that the image regions which share similar depth value will be allocated to similar saliency value. Thirdly, a variation of alternating direction method is proposed to solve the proposed model. Finally, both quantitative and qualitative experimental results on NLPR1000 and NJU400 show the advantage of the proposed RGBD salient object detection model. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Laplace transforms Object recognition RECOVERY
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Mineralization enrichment regularity of gold deposit in Shangzhuang, northwestern Jiaodong
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作者 QI Caisong ZHANG Yuan 《Global Geology》 2013年第2期68-74,共7页
Shangzhuang gold deposit located in the Wangershan fault zone of northwestern Jiaodong is of meso- hypogenic altered rock type. The ore bodies occur at the hanging wall and footwall of Wangershan fault in vein or irre... Shangzhuang gold deposit located in the Wangershan fault zone of northwestern Jiaodong is of meso- hypogenic altered rock type. The ore bodies occur at the hanging wall and footwall of Wangershan fault in vein or irregular shapes with the NE strike, NW trend, 30° -60°~ in dip and the lateral trending of SW. The ores are composed of pyrite, quartz, sericite, bismuthinite, native gold, bismuth sulfosah minerals, chalcopyrite, etc. , shown as brecciated structure and vein structure with metasomatic dissolution textures. The wall rock altera- tion is mainly described as phyllic alteration and silicification. The mineralization of this deposit is controlled by structure and altered rocks. The ore-controlling fault structures of this deposit is Wangershan fault, of which the intersection of major fault and secondary fault is the main ore-bearing position of this gold deposit, and the lar- ger arc curved position is a favorable part for ore body occurrence. On the plane, the ore body is shown as equi- distant pinch-out reproduction. 展开更多
关键词 deposit characteristics ore-controlling regularity Shangzhuang gold deposit
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Structural Connectivity Enhanced Anisotropic 3D Network for Brain Midline Delineation
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作者 Yufan Liu Kongming Liang +6 位作者 Yinuo Jing Shen Wang Zhanyu Ma Yiming Li Yizhou Yu Yizhou Wang Jun Guo 《Journal of Beijing Institute of Technology》 EI CAS 2023年第5期562-578,共17页
Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain m... Brain midline delineation can facilitate the clinical evaluation of brain midline shift,which has a pivotal role in the diagnosis and prognosis of various brain pathology.However,there are still challenges for brain midline delineation:1)the largely deformed midline is hard to localize if mixed with severe cerebral hemorrhage;2)the predicted midlines of recent methods are not smooth and continuous which violates the structural priority.To overcome these challenges,we propose an anisotropic three dimensional(3D)network with context-aware refinement(A3D-CAR)for brain midline modeling.The proposed network fuses 3D context from different two dimensional(2D)slices through asymmetric context fusion.To exploit the elongated structure of the midline,an anisotropic block is designed to balance the difference between the adjacent pixels in the horizontal and vertical directions.For maintaining the structural priority of a brain midline,we present a novel 3D connectivity regular loss(3D CRL)to penalize the disconnectivity between nearby coordinates.Extensive experiments on the CQ dataset and one in-house dataset show that the proposed method outperforms three state-of-the-art methods on four evaluation metrics without excessive computational burden. 展开更多
关键词 brain midline delineation refinement network structure prior connectivity regular loss
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空间结构模型优化的弹性参数FFT-MA随机建模
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作者 黄国娇 曾繁鑫 +2 位作者 王善涛 张宏兵 蒋甫玉 《石油地球物理勘探》 EI CSCD 北大核心 2024年第5期1121-1131,共11页
快速傅里叶变换滑动平均(FFT-MA)法是一种灵活高效的随机建模方法,在地下介质高分辨率建模、复杂介质非平稳建模和不确定性评价等方面具有重要的应用价值。准确构建空间结构模型是利用FFT-MA方法生成合理的随机模型的关键。然而,以往对F... 快速傅里叶变换滑动平均(FFT-MA)法是一种灵活高效的随机建模方法,在地下介质高分辨率建模、复杂介质非平稳建模和不确定性评价等方面具有重要的应用价值。准确构建空间结构模型是利用FFT-MA方法生成合理的随机模型的关键。然而,以往对FFT-MA方法的研究并未提出准确构建空间结构模型的有效方法。为此,文中提出了一种有效的空间结构模型估计方法。该方法基于反演思想,通过最小化随机模型与测井数据和地震数据的空间结构差异,分别估计空间结构模型的纵向自相关长度和横向自相关长度。同时,为了优化空间结构模型的估计效果,在纵向自相关长度的反演过程中引入边界保护正则化,以提高反演的稳定性。此外,将地震约束引入模型优选以提高随机模型的稳定性。实验结果表明:该方法能够稳定估计地下介质的非平稳空间结构模型,从而建立准确描述复杂储层非平稳空间相关特征的高分辨率随机模型。与基于序贯高斯协模拟的随机建模方法相比,使用空间结构模型优化的FFT-MA随机建模方法能够有效刻画多种复杂地质构造从而实现复杂储层建模。 展开更多
关键词 FFT-MA 方法 空间结构模型 参数反演 边界保护正则化 随机建模 非平稳性建模
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考虑结构空间作用的RC框架梁轴向约束刚度研究
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作者 季静 黄芷若 +4 位作者 丁迅 杨坚 林鹏 郑振光 韩小雷 《建筑结构》 北大核心 2024年第20期112-120,111,共10页
为真实反映结构对框架梁的空间约束作用,提出了轴向约束刚度指标以量化结构空间约束,并建立可模拟框架结构空间约束作用的数值模型。对比足尺框架结构试验数据表明,按规范计算的框架梁抗弯承载力与试验值相对误差为42%~75%,考虑结构轴... 为真实反映结构对框架梁的空间约束作用,提出了轴向约束刚度指标以量化结构空间约束,并建立可模拟框架结构空间约束作用的数值模型。对比足尺框架结构试验数据表明,按规范计算的框架梁抗弯承载力与试验值相对误差为42%~75%,考虑结构轴向约束作用后相对误差缩小至25%以内,说明该模型可较好地模拟框架结构轴向约束作用,验证了该数值模型的合理性和可靠性。在有限元软件SAP2000中建立等效弹性数值模型,通过单参数分析得到对RC框架梁轴向约束刚度有显著影响的关键变量。在常见工程的取值范围内对关键变量进行充分的排列组合,开展规模化数值分析并总结结构空间约束的作用机理与RC框架梁极限状态下轴向约束刚度分布规律,得出了极限状态下RC框架梁轴向约束刚度的计算方法。 展开更多
关键词 钢筋混凝土框架结构 结构空间作用 轴向约束刚度 规模化数值分析 分布规律 回归分析
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基于因果正则化极限学习机的风电功率短期预测方法
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作者 杨茂 张书天 王勃 《电力系统保护与控制》 EI CSCD 北大核心 2024年第11期127-136,共10页
随着风电并网比例的逐年提高,电力系统对风电功率预测的准确性和稳定性提出了更高要求。对于同一风电场而言,为了避免不同特征选择方法所选择的风电场特征子集不同,从因果关系的角度出发,提出了一种基于因果正则化极限学习机(causal reg... 随着风电并网比例的逐年提高,电力系统对风电功率预测的准确性和稳定性提出了更高要求。对于同一风电场而言,为了避免不同特征选择方法所选择的风电场特征子集不同,从因果关系的角度出发,提出了一种基于因果正则化极限学习机(causal regularized extreme learning machine, CRELM)的风电功率短期预测方法。首先将极限学习机(extreme learning machine, ELM)建模为结构因果模型(structural causal model, SCM),在此基础上计算隐藏层神经元与输出层神经元之间的平均因果效应向量。然后将该平均因果效应向量与输出层权重相结合构成因果正则化项,在最小化训练误差的同时最大化网络的因果关系,以进一步提升模型的预测准确性和预测稳定性。最后,以国内蒙西某风电场数据为例,与采用特征选择或不采用特征选择的预测模型相对比,验证了所提方法的有效性和适用性。 展开更多
关键词 特征选择 因果正则化 结构因果模型 平均因果效应向量 极限学习机
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The Principle of Square Hole Machining and It's Tooling Structure Design
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作者 Jinxia NIU 《International Journal of Technology Management》 2015年第2期7-8,共2页
In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and pro... In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method: planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. 展开更多
关键词 Abstract: In order to meet the rapid needs of processing square hole in mechanical equipment the paper expounds the square hole processing method: planetary wheel method and analyze the principle of tooling structure and process with computer graphics parameters design. The results that as long as the appropriate parameters using the above method not only can punch the square hole can also be processed triangle the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel. Keywords: Square hole processing Planet wheel Lelo triangle Square hole drilling
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