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Remarkable achievements,splendid future——Celebrating the 45^(th) anniversary of synthetic diamond of china

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金刚石与磨料磨具工程 2008年第S1期28卷 1-19页

作者： Li Zhihong,Zhao Bo,Yi Yunlei,Wang Qin,Hua Shujie,Zhang Hui (zhengzhou Research institute for Abrasives and Grinding,zhengzhou 450013,china)

The development of china as the world’s manufacturing house is best exemplified in the industry of diamond *** is indispensable in the creation of industrial infrastructure,including the construction of roads and building of *** world’s diamond was provided mainly by countries outside china in last ***,a"great leap forward"has taken shape with rapid expansion in Chinese diamond-making capabilities from the enlargement of the equipment(cubic presses) and improvements in diamond yield and product quality in the end of last *** the turn of this century,china outpaced the rest world combined in the total diamond output,became the largest producer in the world *** 2007,china produced nearly 4.4 billion carats,80%of the world’s diamond total *** Chinese diamond well accepted in the world can be seen in the export statistics of china & import statistics of developed countries in this *** example,59%of USA imported diamonds were from china in 2007;in Japan, 40%. This report contains a survey of some main industrial sectors that use diamond ***,22 tables and figures are used to portray the many facets of superabrasives,including cubic boron *** report also discusses several challenges facing Chinese diamonds,such as the vast price difference between imported diamond grit produced outside china and domestic *** paper also presents an outlook of the future development of the Chinese superabrasives industry basing on the Chinese macroeconomics and the recent data of the end-users as well as their future development *** paper concludes by proposing that although remarkable achievements have been made in the past 45 years,given the fact that Chinese superabrasives industry still lags behind that from the advanced countries on a multitude of variables,further endeavor should be made to make china a super country in the superabrasives industry in the world.

关键词： Industrial diamond superabrasives cubic press cubic boron nitride diamond saws

A fingerprint feature extraction algorithm based on curvature of Bezier curve

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Progress in Natural Science:Materials International 2007年第11期17卷 1376-1381页

作者： Yuan Huaqiang1, Ye Yangdong2, Deng Jianguang2, Chai Xiaoguang1 and Li Yong1(1. School of Software, Dongguan University of Technology, Dongguan 523808, china 2. Information Engineering institute, zhengzhou University, zhengzhou 450001, china) School of Software Dongguan University of Technology Dongguan 523808 China Information Engineering institute Zhengzhou University Zhengzhou 450001 China

Fingerprint feature extraction is a key step of fingerprint identification. A novel feature extraction algorithm is proposed in this paper, which describes fingerprint feature with the bending information of fingerprint ridges. Ridges in the specific region of fingerprint images are traced firstly in the algorithm, and then these ridges are fit with Bezier curve. Finally, the point that has the maximal curvature on Bezier curve is defined as a feature point. Experimental results demonstrate that this kind of feature points characterize the bending trend of fingerprint ridges effectively, and they are robust to noise, in addition, the extraction precision of this algorithm is also better than the conventional approaches.

关键词： fingerprint identification feature extraction Bezier curve curvature

Boundary Nevanlinna-pick Interpolation for Meromorphic Functions

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Acta Mathematicae Applicatae Sinica 2002年第2期18卷 255-262页

作者： Gong-ning Chen, Li-xin JiaDepartment of Mathematics, Beijing Normal University, Beijing 100875, china Electronic and Technology institute, zhengzhou 450004, china Department of Mathematics Beijing Normal University Beijing China Electronic and Technology institute Zhengzhou China

Versions of the multiple Nevanlinna-Pick interpolation problem in the class N involving both interior and boundary data are investigated. This leads to solvability criteria for the indicated problems and description o... 详细信息

关键词： Nevanlinna-pick interpolation generalized Pick matrix Hankel vector power moment problem minimally positive Hankel matrix

Research on the Establishment of Navigation Service under Cloud Computing

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Research on the Establishment of Navigation Service under Cl...

Glacigenic Characteristics of the Luoquan Formation and Sediment Gravity Flow Reworking on It

第三届中国卫星导航学术年会

作者： Cui Yang,Lu Zhiping,Chen Zhengshen,Wang Yupu institute of surveying and mapping Information Engineering University,zhengzhou,china

As a fire-new way of network service,cloud computing make network becoming a synthetic medium to transfer service,computing power and *** is bringing about a huge influence on the development of navigation service ***,this paper introduced the limits of existing navigation service model;then preliminarily discussed navigation services under the condition of cloud computing,and designed a flexible framework of navigation cloud services based on general system architecture;and finally,the conclusions and future works are presented.

关键词： cloud computing.system architecture.navigation service.navigation cloud

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Acta Geologica Sinica(English Edition) 1988年第3期1卷 325-339页

作者： Wu Ruitang Guan Baode china University of Geosciences, Wuhan, Hubei Henan institute of Geology, zhengzhou, Henan china University of Geosciences Wuhan Hubei China

The origin of the Luoquan Formation which occurs along the southern margin of the North china Blockhas long been argued. Based on recent work. the Formation is considered as a glacial sedimentary sequencepartially reworked by sediment gravity flow. The major evidence for the glacigene of Luoquan Formationdiamictites is as follows: 1, a striated and polished pavement with various features resulting from glacialabrasion and plucking, such as crescentic gouge, crescentic fracture, streamlined form and glaciated step; *** diamictites with striated clast. faceted clast and iron-shaped stone formed by glaciation; 3. rhythmitewith dropstones; 4. a glacial sedimentary sequence bearing advance-retreat cycles; and 5. wide distribution ofthe diamictites. Glacial deposits can be distinguished from sediment gravity flow deposits by the features men-tioned above. Some characteristics of sediment gravity flow existing in the Luoquan Formation diamictites in-dicate that glacial deposits might have been partially reworked by sediment gravity flow. Therefore, this papersuggests that the Luoquan Formation diamictite is a result of a glacial event rather than a mud flow *** primary tillites are the principal contribution of the Luoquan Formation, while sediment gravity flow de-posits are the redeposited diamictites and should be termed as glacigenic sediment gravity flow deposits.

关键词： Glacigenic Characteristics of the Luoquan Formation and Sediment Gravity Flow Reworking on It

Response of flood discharging capacity to the deterioration of the lower Yellow River

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Science china(Technological Sciences) 2004年第z1期47卷 152-160页

作者： LI Wenxue1, LI Yong2, YAO Wenyi2, SU Yunqi2 & ZHANG Xiaohua2 1. Yellow River Engineering Consulting Co. Ltd., zhengzhou 450003, china 2. Yellow River institute of Hydraulic Research, zhengzhou 450003, china Yellow River institute of Hydraulic Research

Based on the clarifications of the deterioration characteristics of the lower Yellow River (LYR), the influence of river deterioration on flood discharging capacity is studied through theoretical derivation and analysis of field data. This study indicates that response of flood discharging capacity to river deterioration is nonlinear. Sediment depositions in the main channel cause the reductions of dominant discharge and thus the increase of initial flood stage. Reductions in the channel width result in the increases of the rising rate of flood stage and the decrease of flood discharging capacity.

关键词： flood discharging capacity, boundary condition, deterioration, sediment, the lower Yellow River.

Tribological Properties of SiC/Cu Composite at High Temperature

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 888-891页

作者：范冰冰张锐 zhengzhou institute of Aeronautical Industry Management School of Materials Science & Engineering Zhengzhou University

SiC/Cu composites were prepared by hot pressing. The high temperature tribological properties of the composites were investigated. XRD, SEM techniques were carried out to characterize the samples. It is found that the friction coefficient of SiC/Cu composites increases with the increasing SiC content. The SiC reinforcement particles are worn down other than removed by pulling out during the wear test. Oxidation of Cu debris leads to the smooth contacting surface. Ring crack is formed under the cyclic wear test. The crack propagates through the damaged matrix and along the brittle interface between SiC particles and Cu matrix.

关键词： SiC/Cu composite tribological properties high temperature wear ring crack

FORMATION OF QUASICRYSTALLINE PHASE IN RAPIDLY SOLIDIFIED Al-Fe-V-Si ALLOY

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Acta Metallurgica Sinica(English Letters) 1994年第3期7卷 167-170页

作者： GUAN Shaokang, TANG Yali, SHEN Ningfu, ZHAO Dongshanzhengzhou institute of Technology. zhengzhou. chinaHU HanqiUniversity of Science and Technology Beijing. Beijing, china zhengzhou Inst of Technology Zhengzhou China

The icosahedral quasicrvstalline phase (i-phase) with the chemical composition of 82.4at%Al. 8.8at%Fe. 3.6at%V and 5.2at%Si in melt spun Al-Fe-V-Si ribbons was found. It is suggested that the temperature and holding t... 详细信息

关键词： quasicrvstalline phase Al-Fe-V-Si alloy rapid solidification

Scalar Weighed Least Square Combination Model for Clock Offset Prediction

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Scalar Weighed Least Square Combination Model for Clock Offs...