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黄土高原台原阶地乾县试区干湿气候分析 被引量:1
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作者 寸待贵 《干旱地区农业研究》 CSCD 北大核心 1990年第3期31-37,共7页
黄土高原台原阶地乾县试区,位于渭北旱腰带南缘。地多深切沟壑。依据实测和调查,分析研究了试区的降水量、蒸发量、蒸发力、干燥度、水土流失、墒情旱情等资料。试区降水年际年内分布不均,多年平均年降水量为 584.2mm,最少年为 281.9mm... 黄土高原台原阶地乾县试区,位于渭北旱腰带南缘。地多深切沟壑。依据实测和调查,分析研究了试区的降水量、蒸发量、蒸发力、干燥度、水土流失、墒情旱情等资料。试区降水年际年内分布不均,多年平均年降水量为 584.2mm,最少年为 281.9mm;蒸发量较邻近气象站大,涵蓄水分能力差,地下水埋深超过 100m,水浇地只占耕地面积的6.8%,是个易旱区。农业用水主要靠自然降水,农业产量丰歉不稳,应重视做好合理开发利用,以发挥较大的生产潜力。 展开更多
关键词 干湿气候分析 黄土高原 台原阶地
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内蒙古大兴安岭北部台原山地兴安落叶松生长规律的探讨
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作者 祁英 巩玉清 《内蒙古林业调查设计》 1991年第1期13-19,共7页
关键词 兴安落叶松 生长规律 台原山地 内蒙古
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Design and Implementation of an Open Network Security Management Platform 被引量:2
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作者 曹元大 王勇 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期316-320,共5页
In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasib... In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it. 展开更多
关键词 network security management open platform XML RPC SNMP
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Detection of Bluetongue Virus Group-specific Antigen Using Monoclonal Antibody Based Sandwich ELISA 被引量:4
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作者 Pradeep Narayan Gandhale Veerakyathappa Bhanuprakash +3 位作者 Vinayagamurthy Balamurugan Madhusudhan Hosamani Gnanavel Venkatesan Raj Kumar Singh 《Virologica Sinica》 SCIE CAS CSCD 2010年第6期390-400,共11页
A monoclonal antibody (MAb) specific for the bluetongue virus (BTV) group specific antigen (VP7) was characterized for its reactivity with purified virus and recombinant BTV VP7 (rVP7) protein and its suitability for ... A monoclonal antibody (MAb) specific for the bluetongue virus (BTV) group specific antigen (VP7) was characterized for its reactivity with purified virus and recombinant BTV VP7 (rVP7) protein and its suitability for use in the sandwich ELISA.The MAb,designated as 5B5 was specific to VP7 and belongs to IgG2a subclass and was selected for the development of the sELISA in this study.The MAb had a titer of 1:25 with BTV and 1:2 with the rVP7 protein.The sELISA is based on capturing of BTV antigen with VP7 specific MAb followed by detection using BTV polyclonal antiserum raised in rabbits.The assay was evaluated with six cell culture adapted serotypes of BTV that have been isolated from India,1,2,15,17,18 and 23.The assay could detect BTV antigen as early as day 8 in blood.It was also successfully applied for the detection of BTV group specific antigen in clinical samples of blood,washed RBCs,buffy coat and plasma.A total of 102 field samples from animals,suspected of being infected with BTV,were tested and 29.42% were positive.The blood samples were also amplified in cell culture which improved the sensitivity of the assay.Results confirmed that the sELISA is rapid and specific. 展开更多
关键词 BLUETONGUE DIAGNOSIS ELISA Monoclonal antibody Sandwich ELISA
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COMPARISONS OF THE WEST PACIFIC SUBTROPICAL HIGH AND THE SOUTH ASIA HIGH BETWEEN NCEP/NCAR AND ECMWF REANALYSIS DATASETS 被引量:4
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作者 陈雯 智协飞 《Journal of Tropical Meteorology》 SCIE 2008年第2期121-124,共4页
Comparisons of the west Pacific subtropical high with the South Asia High are made using the NCEP/NCAR and ECMWF 500 hPa and 100 hPa monthly boreal geopotential height fields for the period 1961-2000. Discrepancies ar... Comparisons of the west Pacific subtropical high with the South Asia High are made using the NCEP/NCAR and ECMWF 500 hPa and 100 hPa monthly boreal geopotential height fields for the period 1961-2000. Discrepancies are found for the time prior to 1980. The west Pacific subtropical high in the NCEP/NCAR data is less intense than in ECMWF data before 1980. The range and strength of the west Pacific subtropical high variation described by the NCEP/NCAR data are larger than those depicted by ECMWF data. The same situation appears in the 100-hPa geopotential field. These discoveries suggest that the interdecadal variation of the two systems as shown by the NCEP/NCAR data may not be true. Besides, the South Asia High center in the NCEP/NCAR data is obviously stronger than in the ECMWF data during the periods 1969, 1979-1991 and 1992-1995. Furthermore, the range is larger from 1992 to 1995. 展开更多
关键词 reanalysis datasets west Pacific subtropical high South Asia High comparisons
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Quantitative Analysis of the Reduction Kinetics of a Pt(Ⅱ) Precursor in the Context of Pt Nanocrystal Synthesis 被引量:1
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作者 Shan Zhou Tung-HanYang +1 位作者 MingZhao YounanXia 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第4期370-374,613,共6页
In this letter, we report a quantitative analysis of how a Pt(II) precursor is reduced to atoms at different temperatures for the formation of Pt nanocrystals with different morphologies and sizes. Our results sugge... In this letter, we report a quantitative analysis of how a Pt(II) precursor is reduced to atoms at different temperatures for the formation of Pt nanocrystals with different morphologies and sizes. Our results suggest that in the early stage of a synthesis, the Pt(II) precursor is reduced to atoms exclusively in the solution phase, followed by homogeneous nucleation to generate nuclei and then seeds. At a relatively low reaction temperature such as 22℃, the growth of the seeds is dominated by autocatalytic surface reduction that involves the adsorption and then reduction of the Pt(II) precursor on the surface of the just-formed seeds. This particular growth pathway results in relatively large assemblies of Pt nanocrystals. When the reaction temperature is increased to 100 ℃, the dominant reduction pathway will be switched from surface to solution phase, producing much smaller asselnblies of Pt nanocrystals. Our results also demonstrate that a similar trend applies to the seed-rnediated growth of Pt nanocrystals in the presence of Pd nanocubes. 展开更多
关键词 Kinetic model Nanocrystal synthesis Precursor reduction
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Experimental study on explosive mechanism of spontaneous combustion gangue dump 被引量:1
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作者 PAN Rong-kun YU Ming-gao LU Lai-xiang 《Journal of Coal Science & Engineering(China)》 2009年第4期394-398,共5页
In order to explore the reason for the frequency explosion of spontaneous combustion coal gangue dump and get to know their explosion mechanism, established the experiment platform about spontaneous combustion coal ga... In order to explore the reason for the frequency explosion of spontaneous combustion coal gangue dump and get to know their explosion mechanism, established the experiment platform about spontaneous combustion coal gangue dump interoperable water. The gangue dump was heated using the external heat source, and rainy weather through water mist was simulated. Simulated experiment about explosion of spontaneous combustion coal gangue dump was carried out on the different conditions of the rainfall or not. The unusual gases produced in the course of gangue combustion and the changes in temperature were observed, and their impacts on the explosion of gangue dump were analyzed. The experimental results show that overall warming phenomenon of the gangue dump after watering occurred, the amount of H2 is three times than that before watering, and the amount of CO is far greater than that on the conditions of no-watering, at the same time combining with local observation and tests. It is found that the content of the oxygen reduce with the temperature increasing; however, gangue dump internal hydrogen content increase unusually on the rainfall conditions at 90 ℃, but the local measuring points reach the explosion limit. The existence of the CO and H2 is the main reason for inducing the explosion of spontaneous combustion coal gangue dump. 展开更多
关键词 coal gangue spontaneous combustion gangue dump explosive mechanism
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Basal stacking fault induced twin boundary gliding,twinning disconnection and twin growth in hcp Ti from the first-principles 被引量:3
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作者 Qi QIAN Zheng-qing LIU +3 位作者 Yong JIANG Yi-ren WANG Xing-long AN Min SONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第2期382-390,共9页
First-principles calculations were performed to investigate the structures and energetics of {101n} coherent twin boundaries(CTBs) and glide twin boundaries(GTBs) in hexagonal close-packed(hcp) Ti. The formation mecha... First-principles calculations were performed to investigate the structures and energetics of {101n} coherent twin boundaries(CTBs) and glide twin boundaries(GTBs) in hexagonal close-packed(hcp) Ti. The formation mechanism of GTBs and their correlation with twin growth were fundamentally explored. Results suggested that GTBs can form from the gliding of CTBs, through their interaction with basal stacking fault. The gliding eventually restored the CTB structures by forming a pair of single-layer twinning disconnections. The pile-up of twinning disconnections should be responsible for the wide steps at twin boundaries as observed in high-resolution transmission electron microscopy, which can further promote twin growth. Possible effects of various alloying elements on pinning twin boundaries were also evaluated, to guide the strengthening design of Ti alloys. 展开更多
关键词 twin boundary stacking fault twinning disconnection twin growth first principles
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Investigation on the Cause of Excessive Vibration of an Offshore Platform
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作者 嵇春艳 《High Technology Letters》 EI CAS 2003年第2期37-43,共7页
An offshore platform of jacket type in Bohai Bay vibrated excessively under design environmental conditions, which had affected the normal operation of the platform. In order to mitigate the vibration of the platform,... An offshore platform of jacket type in Bohai Bay vibrated excessively under design environmental conditions, which had affected the normal operation of the platform. In order to mitigate the vibration of the platform, it is essentially important to explore the cause of the vibration. So the objective of this study is to investigate the cause of the excessive vibration. In this paper, dynamic characteristics of the offshore platform is analyzed by numerical simulation using finite element (FE) modeling. For further verifying the numerical results, model experiment is conducted. Numerical and experimental results demonstrate that there is relative movement and impact between the piles and the jacket, i.e. the piles and the jacket didnt connect well to an entity. It is this cause that the stiffness of the platform decreases and the impact between piles and the jacket legs induces excessive vibration. And also the grouting measure is advised to reduce the vibration of the offshore platform according to the analysis results. 展开更多
关键词 dynamic analysis offshore platform physical model wave loading FE modeling
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Experimental and simulated studies on hydraulic buffering valve for ZF-4WG308 power-shift transmission 被引量:3
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作者 王飞 王宇 +1 位作者 韩嘉骅 姚进 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第8期1801-1807,共7页
The structure and working principle of a hydraulic buffering valve for a power-shift transmission ZF-4WG308 were studied comprehensively, and a model of the hydraulic buffering valve was developed with AMESim. A bench... The structure and working principle of a hydraulic buffering valve for a power-shift transmission ZF-4WG308 were studied comprehensively, and a model of the hydraulic buffering valve was developed with AMESim. A bench test was conducted on a buffering valve for transmissions(ZF-4WG308) and the test results agree well with the simulated results. Further more, the influences of the key parameters of the valve on the buffering performance were also studied in details. 展开更多
关键词 shifting quality hydraulic buffering valve AMESim
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Time Domain Simulation of a One Line Failure for a DP-assisted Mooring System 被引量:4
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作者 Jianxun Zhu Liping Sun Shengnan Liu Jichuang Kang 《Journal of Marine Science and Application》 2014年第3期321-326,共6页
This paper focuses on the research of a semi-submersible platform equipped with a DP-assisted mooring system. Based on the working principles of the DP-assisted mooring system and the model of the platform motion, a t... This paper focuses on the research of a semi-submersible platform equipped with a DP-assisted mooring system. Based on the working principles of the DP-assisted mooring system and the model of the platform motion, a time domain simulation program is applied to analyze the impact, in the case of one line failure, on the platform motion, power consumption of the thrusters and the tension of the mooring lines. The results show that, under the 10-year wind dominant, a one line failure will have little impact on the tension of the mooring lines. When the failure line is windward, the power consumption will increase greatly with a weakened position of accuracy. However when the failure line is leeward, the power consumption will be reduced with a partly strengthened oosition of accuracy. 展开更多
关键词 DP-assisted mooring system time domain simulation one line failure semi-submersible platform.
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Association between MDM2-SNP309 and hepatocellular carcinoma in Taiwan Residents population 被引量:6
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作者 Jyh-Der Leu I-Feng kin +3 位作者 Ying-Fang Sun Su-Mei Chen Chih-Chao Liu Yi-Jang Lee 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第44期5592-5597,共6页
AIM:To investigate the risk association and compare the onset age of hepatocellular carcinoma(HCC) patients in Taiwan with different genotypes of MDM2- SNP309. METHODS:We analyzed MDM2-SNP309 genotypes from 58 patient... AIM:To investigate the risk association and compare the onset age of hepatocellular carcinoma(HCC) patients in Taiwan with different genotypes of MDM2- SNP309. METHODS:We analyzed MDM2-SNP309 genotypes from 58 patients with HCC and 138 cancer-free healthy controls consecutively.Genotyping of MDM2-SNP309 was conducted by restriction fragment length polymor- phism assay. RESULTS:The proportion of homozygous MDM2- SNP309 genotype(G/G)in cases and cancer-free healthy controls was similar(17.2%vs 16.7%).Multi-variate analysis showed that the risk of G/G genotypeof MDM2-SNP309 vs wild-type T/T genotype in patients with HCC was not significant(OR=1.265,95% CI=0.074-21.77)after adjustment for sex,hepatitis B or C virus infection,age,and cardiovascular disease/ diabetes.Nevertheless,there was a trend that GG genotype of MDM2-SNP309 might increase the risk in HCC patients infected with hepatitis virus(OR=2.568, 95%CI=0.054-121.69).Besides,the homozygous MDM2-SNP309 genotype did not exhibit a significantly earlier age of onset for HCC. CONCLUSION:Current data suggest that the asso- ciation between MDM2-SNP309 GG genotype and HCC is not significant,while the risk may be enhanced in patients infected by hepatitis virus in Taiwan. 展开更多
关键词 MDM2 protein Hepatocellular carcinoma TAIWAN Tumor suppressor protein p53
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Atomic layer deposition: Catalytic preparation and modification technique for the next generation 被引量:5
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作者 Hongbo Zhang Christopher L. Marshall 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第9期1311-1323,共13页
Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular level.There are several reported review papers published recently discuss... Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular level.There are several reported review papers published recently discussing this technique in catalysis.However,the mechanism on how the deposited materials improve the catalyst stability and tune the reaction selectivity is still unclear.Herein,catalytic systems created via ALD on stepwise preparation and/or modification under self-limiting reaction conditions are summarized.The effects of deposited materials in terms of electronic/geometry modification over the catalytic nanoparticles(NPs)are discussed.These effects explain the mechanism of the catalytic stability improvement and the selectivity modification.The unique properties of ALD for designing new catalytic systems are further investigated for building up photocatalytic reaction nanobowls,tandem catalyst and bi-active-component metallic catalytic systems. 展开更多
关键词 Atomic layer deposition Catalyst modification Catalyst preparation Redox properties Terrace site Step site
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The Design of Desk Lamp on 3D Modeling based on Solidworks 被引量:1
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作者 Mingxin Li 《International Journal of Technology Management》 2013年第1期43-45,共3页
This paper introduces the solidworks design flow, design methods and design principles of desk lamp. And we use the ergonomics principle, analysis the function of each part of the lamp, and analyses the design of lamp... This paper introduces the solidworks design flow, design methods and design principles of desk lamp. And we use the ergonomics principle, analysis the function of each part of the lamp, and analyses the design of lamp components, to meet user needs in the bedroom, do practical, human nature and convenient lamp. The application shows that the use of this software can make easier the realization of the design of the parts with complex shape, raise the design efficiency, optimize the product structure and save the cost. 展开更多
关键词 SOLIDWORKS Desk lamp 3D model
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Multicultural Citizenship Education: A Study on Experiences and Opinions of Taiwan's Indigenous Elementary School Teachers
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作者 Amy Shumin Chen 《Sociology Study》 2013年第11期875-888,共14页
The author reports findings of multicultural citizenship education from a two-year in-depth study of indigenous principals and teachers in local elementary schools. Data were gathered and analyzed using a conceptual f... The author reports findings of multicultural citizenship education from a two-year in-depth study of indigenous principals and teachers in local elementary schools. Data were gathered and analyzed using a conceptual framework that consisted of a multicultural citizenship based on the liberal theoretical perspective. The results indicate that indigenous educators face dilemmas in being cultural elites while considered national education policy implementer. Findings illustrate that indigenous elementary school educators are expected to possess differentiated-group privileges in teaching practices; however, they are confronted with both internal restrictions and external protections during establishing of ethnic cultural identity while playing their roles in the national educational apparatus. The paper also gives conclusions and suggestions for future researches. 展开更多
关键词 Multicultural citizenship IDENTITY indigenous right EDUCATION
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Marked Advance in Widths and Heights of Harmonic Plateau
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作者 陈高 朱颀人 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第4期759-763,共5页
We propose a scheme to simultaneously widen and heighten the high-order harmonic plateau on a large scale. More specifically, by adopting a united two-atom system with a suitable inter-nuclear separation instead of a ... We propose a scheme to simultaneously widen and heighten the high-order harmonic plateau on a large scale. More specifically, by adopting a united two-atom system with a suitable inter-nuclear separation instead of a single-atom, the harmonic plateau is widened from Ip + 3.2Up to Ip +8.5Up; further, by adopting the combined pulse, the extended plateau (harmonics near Ip+ 5.6Up) is selectively heightened in excess of 4 orders of magnitude compared with the case of the low-frequency pulse alone. By means of the wavelet transform for the induced dipole of these harmonics, a single x-ray pulse as short as 210 asec is achieved. 展开更多
关键词 high-order harmonic generation united two-atom model combined pulse
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Research on Crustal Flow and Its Dynamic Characteristics in Sichuan and Its Adjacent Area
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作者 Fan Jun Zhu Jieshou +2 位作者 Jiang Xiaotao Wu Peng Yang Yihai 《Earthquake Research in China》 CSCD 2016年第1期57-73,共17页
Using the broadband seismic data of the regional stations in the Sichuan Digital Seismic Network and the mobile seismic stations in this region,the receiver function inversion method was adopted to study the character... Using the broadband seismic data of the regional stations in the Sichuan Digital Seismic Network and the mobile seismic stations in this region,the receiver function inversion method was adopted to study the characteristics of crustal flow and dynamic effects in Sichuan and adjacent areas. The results show that: Velocity in the crust and upper mantle of the Sichuan basin is significantly higher than that beneath the eastern margin of the Qinghai-Tibetan plateau. The velocity v_S is from 3. 6 to 3. 8km / s in the crust and4. 5- 4. 8km / s in the upper mantle beneath the basin,and there is no low-velocity layer in the crust. The lithology shows a hard block. The v_S velocity in the eastern margin of the Qinghai-Tibetan plateau is lower,with average v_Sof 3. 0- 3. 4km / s in the mid crust and4. 0- 4. 5km / s in the upper mantle. Low-velocity layers are distributed widely in the crust,most of which are in the mid crust at a depth of 20km- 40 km,and there are also a few low-velocity layers appearing in the upper crust at depths of 10km- 20 km and the lower crust at depths of 40km- 60 km. Affected by the northward pushing of the Indian plate,the eastward movement of the eastern margin of the Qinghai-Tibetan plateau is blocked by the hard Sichuan basin,producing a southward and southeastward component.Such movement process is produced by the complicated forces acting in this area. Just under the action of these forces, the eastern margin of the Qinghai-Tibetan plateau becomes a region with complicated geology and intensive earthquake activity. Obstructed by the hard Sichuan basin,the low-velocity crustal flow is delaminated and split into two or three upward and downward tributaries. The upward flow intruded into the upper crust,causing uplift of the earths urface,forming mountain crests; the downward flow intruded into the lower crust and upper mantle,resulting in thickening of the crust and depression of the Moho. The crustal flow in the eastern margin of the Qinghai-Tibetan plateau is mainly distributed along the active faults. The crustal flow flows out from the Qiangtang block in the middle part of the eastern margin of the Qinghai-Tibetan plateau,the mainstream flows along the NW-SE trending Xianshuihe fault zone,then turns NS and flows to the south along the Anninghe and Xiaojiang faults. There is another crustal flow in the north of the study area,flowing in the NE and E-W directions to the Longmenshan faults. 展开更多
关键词 Sichuan and its adjacent area Receiver function Crustal flow Dynamiccharacteristics
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Kineto-static analysis of a novel high-speed parallel manipulator with rigid-flexible coupled links 被引量:2
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作者 孙涛 宋轶民 阎凯 《Journal of Central South University》 SCIE EI CAS 2011年第3期593-599,共7页
A novel high-speed parallel kinematic machine (PKM) named Delta-S parallel manipulator is proposed, which consists of a fixed base connected to a moving platform through three limbs with identical topology. Each lim... A novel high-speed parallel kinematic machine (PKM) named Delta-S parallel manipulator is proposed, which consists of a fixed base connected to a moving platform through three limbs with identical topology. Each limb is composed of one driving ann and one follower arm, herein, the latter includes two strings and one middle rod, all located in a same plane. Compared with similar manipulators with uniform parameters, the novel and unique topology as well as the addition of two strings of Delta-S manipulator can remove the clearance of the spherical joints, reduce the inertial load of components further, improve the positioning accuracy and dynamic performance, and so on. In order to formulate the kineto-static model of Delta-S manipulator, the kineto-static analyses and models of the driving arm, the generalized follower and the moving platform can be carried out by the D'ALEMBERT principle. For the sake of obtaining the force analytic results of strings, the deformation compatibility condition of strings and the middle rod are determined. Furthermore, in virtue of the assumption of small deformation and the linear superposition principle, the minimal pre-tightening force of the strings is calculated. The main results include that the loads of the strings and the middle rod must be larger than "zero" and the pre-tightening force over the workspace must be larger than the minimal pre-tightening force at any time within the workspace, which lay the foundation for the dynamic analysis and the prototype manufacture of the Delta-S manipulator. 展开更多
关键词 parallel kinematic machines (PKMs) Delta-S manipulator kineto-static analysis deformation compatibility condition pre-tightening force
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Analysis of Development Causes and Reasons on Logistics Public Information Platform in Road Freight Market of China
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作者 Xu Jing 《International Journal of Technology Management》 2016年第8期43-45,共3页
This paper based on the analysis and comparison of two major changes of our road freight market affected by reforming andopening-up, and discusses that the origin, course and motivation of the Logistics public informa... This paper based on the analysis and comparison of two major changes of our road freight market affected by reforming andopening-up, and discusses that the origin, course and motivation of the Logistics public information platform(LPIP). Then it Points that theessential reason is the asymmetry of information exchange, course of its development is in order to meet the different needs of different stagesof the market continuously adjusted to the function of a process of development, but also development of the market to a specifi c stage of theinevitable demand. 展开更多
关键词 LOGISTICS information platform road freight
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五陵原水资源及水文状况 被引量:1
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作者 梁安和 《秦汉研究》 2012年第1期103-111,共9页
五陵原位于渭河平原腹地,是关中平原的重要组成部分,东西跨越兴平市、秦都区、渭城区、泾阳县以及西安市高陵县部分地区,属于渭河谷地向黄土台原的过度地带,从西到东海拔480米到410米,落差约70米不等,南北从渭河的一、二级阶地过渡到黄... 五陵原位于渭河平原腹地,是关中平原的重要组成部分,东西跨越兴平市、秦都区、渭城区、泾阳县以及西安市高陵县部分地区,属于渭河谷地向黄土台原的过度地带,从西到东海拔480米到410米,落差约70米不等,南北从渭河的一、二级阶地过渡到黄土台原,最宽的地区约20余公里,最窄的地方约1公里多一点,海拔从380米到500米,落差约120米不等。 展开更多
关键词 高陵县 黄土 泾阳县 台原 渭河 五陵 秦都区
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