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1956年山西晋城县云台、封门、西冻水三村割属河南研究
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作者 祁毓龙 《太原理工大学学报(社会科学版)》 2016年第4期29-33,共5页
在微观尺度下探究政区改易问题,有利于更为深刻地认识政区改易背后多元复杂的"联系"。1956年,山西晋城县云台、封门、西冻水三村群众要求改属河南。面对此三村提出改属要求,中央、省、专署、乡政府等多种不同群体对此事情的看... 在微观尺度下探究政区改易问题,有利于更为深刻地认识政区改易背后多元复杂的"联系"。1956年,山西晋城县云台、封门、西冻水三村群众要求改属河南。面对此三村提出改属要求,中央、省、专署、乡政府等多种不同群体对此事情的看法,不仅体现了当时大背景下的社会风貌,还展示了民众之间、官民之间、官官之间、上下级之间的多重互动与博弈。文章以这次小尺度的政区改易行动,考察事件背后多重人物、群体之间的互动关系,勾勒不同群体对政区割属的影响。 展开更多
关键词 行政区划 政区地理 割属 云台 封门 西冻水
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西藏割舌树植物(楝科)的订正 被引量:2
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作者 陶德定 《植物分类学报》 CSCD 1994年第4期369-369,共1页
西藏割舌树Walsura xizangensis是吴征镒和李恒于1980建立的。近年来多位学者相继来函借阅该种命名模式标本(青藏队74—4540)进行研究,均认为该号模式标本不属楝科,但不知是什么植物。笔者经研究发现它原来是Glycosmis motuoensis D.D.... 西藏割舌树Walsura xizangensis是吴征镒和李恒于1980建立的。近年来多位学者相继来函借阅该种命名模式标本(青藏队74—4540)进行研究,均认为该号模式标本不属楝科,但不知是什么植物。笔者经研究发现它原来是Glycosmis motuoensis D.D.Tao。 展开更多
关键词 舌树 楝科 分类
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米兰山小橘(芸香科)的分类订正(英文) 被引量:2
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作者 牟凤娟 马士祝 +1 位作者 李双智 张奠湘 《广西植物》 CAS CSCD 北大核心 2011年第6期711-717,共7页
对芸香科山小橘属米兰山小橘进行了分类订正,根据模式标本查阅及原始文献相关特征描述,该种属于楝科割舌树属已知种类,将其处理为割舌树的异名。
关键词 山小橘 米兰山小橘 舌树 舌树 异名
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Finite Element Analysis and OADs Optimization of the Temperature in the Plane-strain Orthogonal Metal Cutting Process 被引量:1
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作者 刘龙权 姚振强 袁光杰 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期29-33,共5页
In order to analyze the influences of the different tool’s shape and surface conditions (such as different coated and material) and their interaction on the cutting temperature, a coupled thermo-mechanical finite ele... In order to analyze the influences of the different tool’s shape and surface conditions (such as different coated and material) and their interaction on the cutting temperature, a coupled thermo-mechanical finite element analysis (FEA) model of plane-strain orthogonal metal cutting process is constructed, and 16 simulation cases with 16 different types of tools, which cover 4 rake angles, -10°, 0°, 10°, 20°, and 4 friction coefficient values, 0, 0.1, 0.2, 0.3 in the same cutting condition (cutting depth and cutting speed) have been performed. Finally the simulation results are analyzed according to the variance analysis method (VAM) of orthogonal array designs (OADs), the relationships between the rake angle, tool-workpiece interface’s friction coefficient and their interact effect to the maximum temperature value and the temperature field of the chip are obtained. This result has some instructive meaning to analyze the causes of the cutting temperature and to control the maximum temperature value and the overall temperature field in the metal cutting process. 展开更多
关键词 FEA Metal cutting OADs Interact effect Maximum temperature value.
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3D modeling of geological anomalies based on segmentation of multiattribute fusion 被引量:1
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作者 Liu Zhi-Ning Song Cheng-Yun +3 位作者 Li Zhi-Yong Cai Han-Peng Yao Xing-Miao Hu Guang-Min 《Applied Geophysics》 SCIE CSCD 2016年第3期519-528,581,共11页
3D modeling of geological bodies based on 3D seismic data is used to define the shape and volume of the bodies, which then can be directly applied to reservoir prediction, reserve estimation, and exploration. However,... 3D modeling of geological bodies based on 3D seismic data is used to define the shape and volume of the bodies, which then can be directly applied to reservoir prediction, reserve estimation, and exploration. However, multiattributes are not effectively used in 3D modeling. To solve this problem, we propose a novel method for building of 3D model of geological anomalies based on the segmentation of multiattribute fusion. First, we divide the seismic attributes into edge- and region-based seismic attributes. Then, the segmentation model incorporating the edge- and region-based models is constructed within the levelset- based framework. Finally, the marching cubes algorithm is adopted to extract the zero level set based on the segmentation results and build the 3D model of the geological anomaly. Combining the edge-and region-based attributes to build the segmentation model, we satisfy the independence requirement and avoid the problem of insufficient data of single seismic attribute in capturing the boundaries of geological anomalies. We apply the proposed method to seismic data from the Sichuan Basin in southwestern China and obtain 3D models of caves and channels. Compared with 3D models obtained based on single seismic attributes, the results are better agreement with reality. 展开更多
关键词 Geological anomaly multiattributes FUSION SEGMENTATION 3D modeling
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Brain MRI Segmentation Using KFCM and Chan-Vese Model 被引量:1
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作者 吴一全 侯雯 吴诗婳 《Transactions of Tianjin University》 EI CAS 2011年第3期215-219,共5页
To extract region of interests (ROI) in brain magnetic resonance imaging (MRI) with more than two objects and improve the segmentation accuracy, a hybrid model of a kemel-based fuzzy c-means (KFCM) clustering al... To extract region of interests (ROI) in brain magnetic resonance imaging (MRI) with more than two objects and improve the segmentation accuracy, a hybrid model of a kemel-based fuzzy c-means (KFCM) clustering algorithm and Chan-Vese (CV) model for brain MRI segmentation is proposed. The approach consists of two succes- sive stages. Firstly, the KFCM is used to make a coarse segmentation, which achieves the automatic selection of initial contour. Then an improved CV model is utilized to subdivide the image. Fuzzy membership degree from KFCM clus- tering is incorporated into the fidelity term of the 2-phase piecewise constant CV model to obtain accurate multi-object segmentation. Experimental results show that the proposed model has advantages both in accuracy and in robustness to noise in comparison with fuzzy c-means (FCM) clustering, KFCM, and the hybrid model of FCM and CV on brain MRI segmentation. 展开更多
关键词 brain magnetic resonance imaging image segmentation kernel-based fuzzy c-means clustering ChanVese model
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Uniform wire segmentation algorithm of distributed interconnects
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作者 尹国丽 Lin Zhenghui 《High Technology Letters》 EI CAS 2007年第2期198-202,共5页
A uniform wire segmentation algorithm for performance optimization of distributed RLC interconnects was proposed in this paper. The optimal wire length for identical segments and buffer size for buffer inser-tion are ... A uniform wire segmentation algorithm for performance optimization of distributed RLC interconnects was proposed in this paper. The optimal wire length for identical segments and buffer size for buffer inser-tion are obtained through computation and derivation, based on a 2-pole approximatian model of distribut-ed RLC interconnect. For typical inductance value and long wires under 180nm technology, experiments show that the uniform wire segmentation technique proposed in the paper can reduce delay by about 27%~56%, while requires 34%~69% less total buffer usage and thus 29% to 58% less power consump-tion. It is suitable for long RLC interconnect performance optimization. 展开更多
关键词 distributed RLC interconnect uniform wire segmentation buffer insertion driver modeling
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Dry Milling of the Ultra-High-Strength Steel 30CrMnSiNi2A with Coated Carbide Inserts 被引量:2
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作者 牛秋林 董大鹏 +2 位作者 陈明 张余升 王呈栋 《Journal of Shanghai Jiaotong university(Science)》 EI 2013年第4期468-473,共6页
The ultra-high-strength steel (UHSS) plays an important role in the mechanical industry because of their special performances. The machinability of 30CrMnSiNi2A steel was studied in dry milling with two different co... The ultra-high-strength steel (UHSS) plays an important role in the mechanical industry because of their special performances. The machinability of 30CrMnSiNi2A steel was studied in dry milling with two different coated tools in the present work. This paper introduced that 30CrMnSiNi2A steel was a kind of diffficult-to-machine materials. The results showed that the cutting force components of feed direction and cutting width direction, i.e. Fx and Fy, increased slightly with increasing the cutting speed and feed rate. The values of axial force component Fx were much larger than Fx and Fy, and increased obviously with increasing the milling speed. The workpiece surface had the minimum roughness at the cutting speed of 150 m/min. The physical vapor deposition (PVD) coated ((Ti, A1)N-TiN) insert was more suitable for machining 30CrMnSiNi2A steel than the chemical vapor deposition (CVD) coated (Ti(C, N)-Al2O3) insert. Moreover, the main failure modes of PVD-coated insert were micro-chipping and coating spalling. The wear modes of CVD-coated insert were ploughing, coating spalling, and cratering. The serious adhesive wear and the abrasion with some adhesion were the main wear mechanism of PVD- and CVD-coated inserts, respectively. 展开更多
关键词 30CRMNSINI2A ultra-high-strength steel (UHSS) coated carbide dry milling
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