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Research on Rapid Response Schematic Design for Flexible Transfer Line CAPP-Based

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厦门大学学报（自然科学版） 2002年第S1期41卷 174-175页

作者： GAO Ju-hong 1, XU Yan-shen 2.(1. Department of Industrial Engineering, School of Management, tianjin university, 2. Department of Mechanical Engineering, School of Management, tianjin Univers ity, tianjin 300072. China)

To meet the market requirements for Flexible Transf er Line (FTL), which consists of modular NC machining tools of high quality and co st saving, the methodologies and technologies of client-oriented FTL rapid resp onse schematic design CAPP-based, one of the key techniques, are presented in t his paper. In order to achieve this purpose, an integrated system for integrated design of CAD/CAPP/FTL with box-type parts is realized. In this paper, firstly the theory of the conceptual design of FTL based on CAPP is established and the software architecture is developed. The global-domain pr oduct model is put forward to meet with data representation. After the manufactu ring feature is analyzed and decomposed for machining operations, the feature-b ased part unified data model object-oriented is built. Secondly the knowledge- based CAPP system data model is established. The process planning unit model is formed by work element (WE), which is tool-cell based function abstraction meth od, and has unified layers with respect to designing and manufacturing. With WEs through dynamic response and simultaneous structure in process planning, the pr inciple solution for CAPP function system can be implemented. Lastly the mapping from process domain to module design domain is built. The unidirectional select ion process based on fuzzy matching technology is easily dealt with computer. Th e algorithm of decision with fuzzy synthetic evaluation method and technology is applied to estimate the feasibility of the results in local working procedure o f modular NC machine tools and make decision of designs in overall FTL, which co nsists of many different factors. The example shows that the rapid response desi gn in bidding-based FTL scheme design is realized.

关键词： CAPP flexible transfer line product model rapi d response design

RuCl_3·3H_2. Mediated Olefin Isomerizations in Ionic Liquids: A Highly Recyclable System for Olefin Isomerizations

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Chemical Research in Chinese Universities 2012年第1期28卷 67-69页

作者： SHAO Ming-bo1, LIU Gui-yan2. ZHAO Jing-jing1, WANG Xiao-yu1 and WANG Jian-hui1 1. Department of Chemistry, College of Science, tianjin university, tianjin 300072. P. R. China 2. tianjin Key Laboratory of Structure and Performance for Functional Molecule, College of Chemistry, tianjin Normal university, tianjin 300387, P. R. China Department of Chemistry College of Science Tianjin University Tianjin 300072 College of Chemistry Tianjin Normal University Tianjin Key Laboratory of Structure and Performance for Functional Molecule Tianjin 300387

Herein lies a convenient and highly efficient method of olefin isomerization in the presence of RuCl3？3H2. in ionic liquid（IL）. More importantly, RuCl3？3H2. is a robust and recyclable catalyst. Nine cycles of RuCl... 详细信息

关键词： Ruthenium trichloride Ionic liquid Olefin isomerization

The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, China

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Science China Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2. Faculty of Earth Sciences and Mineral Resources, China university of Geosciences, Beijing 100083, China 3. tianjin Institute of Geology and Mineral Resources, tianjin 300170, China 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing 100083 China 3. tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

China Galileo Test Range and Its Critical Technologies

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Transactions of tianjin university 2009年第6期15卷 463-470页

作者：刘学林蔚保国 School of Management Tianjin University The 54th Research Institute of CETC

With the rapid development of global navigation satellite system (GNSS) and its applications, GNSS test range is becoming the focus of research. This paper, with the cooperation on Galileo Program between Europe and China as background, gives an overview of the development of test ranges for satellite navigation, proposes an implementation plan for China Galileo Test Range (CGTR), presents an analysis of CGTR and describes its overall objective, architecture, function and services, as well as operating modes. Particular analysis and study are given to the critical technologies related to CGTR implementation, including test range simulation and evaluation, time syn-chronizing and keeping, and pseudolite time division multiple access (TDMA) signal design. Research results of this paper can be helpful to GNSS testing and related applications.

关键词： CGTR Galileo satellite navigation test range

Design and performance of dual-band high temperature superconducting filter

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Science China(Information Sciences) 2012年第4期55卷 956-961页

作者： JI LaiYun 1,MA Jie 1,2.SUN Jun 1,WANG Lang 1,LI YanQi 1 & LIU Bin 1 1 tianjin Hi-Tech Superconducting Electronic Co.Ltd,tianjin 300384,China 2.Department of Information Engineering,Hebei {2. of technology,tianjin 300130,China 1. tianjin Hi-Tech Superconducting Electronic Co. Ltd Tianjin 300384 China2. Department of Information Engineering Hebei University of Technology Tianjin 300130 China

In this paper,a dual-band high temperature superconducting (HTS) filter with 14-pole and 3 cross couplings is *** equivalent model,theoretical result,coupling matrix,and the simulated result of the filter are *** desired filter is designed and fabricated using double-sided DyBa 2.Cu 3 O 7 thin films on MgO wafer 2.inches in diameter and 0.5 mm in *** filter has two passbands with frequencies 192.-1940 MHz and 1960-1980 MHz respectively,and insertion loss less than 0.2.*** measurement results show that the response of practical filters is in good agreement with that of simulated results and theoretical analysis,with the group delay variation being less than ±2. ns over 90% of the filter bandwidth for the two passbands.

关键词： HTS filter dual-band cross-coupling cascaded quadruplet structure

Seismic Reliability and Rehabilitation Decision of Water Distribution System

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Transactions of tianjin university 2010年第3期16卷 223-228页

作者：柳春光何双华 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Faculty of Infrastructure Engineering Dalian University of Technology

In order to evaluate the seismic reliability of water distribution system and make rehabilitation decisions correspondingly, it is necessary to assess pipelines damage states and conduct functional analysis based on pipe leakage model. When an earthquake occurred, the water distribution system kept serving with leakage. By adding a virtual node at the centre of the pipeline with leakage, an efficient approach to pressure-driven analysis was developed for simulating a variety of low relative scenarios, and a hydraulic leakage model was also built to perform hydraulic analysis of the water supply network with seismic damage. Then the mean-first-order-second-moment method was used to analyse the seismic serviceability of the water distribution system. According to the assessment analysis, pipes that were destroyed or in heavy leakage were isolated and repaired emergently, which improved the water supply capability of the network and would constitute the basis for enhancing seismic reliability of the system. The proposed approach to seismic reliability and rehabilitation decision analysis on water distribution system is demonstrated effective through a case study.

关键词： water distribution system hydraulic analysis leakage model seismic reliability rehabilitation decision

Threading dislocation density comparison between GaN grown on the patterned and conventional sapphire substrate by high resolution X-ray diffraction

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 465-468页

作者： ZHANG YuChao1, XING ZhiGang2. MA ZiGuang2. CHEN Yao2. DING GuoJian2. XU PeiQiang2. DONG ChenMing3, CHEN Hong2.& LE XiaoYun1 1 School of Physics and Nuclear Energy Engineering, Beihang university, Beijing 100190, China 2.Renewable Energy Laboratory, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China 3 School of Information and Communication, tianjin Polytechnic university, tianjin 300160, China 1. School of Physics and Nuclear Energy Engineering Beihang University Beijing 100190 China2. Renewable Energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing 100190 China3. School of Information and Communication Tianjin Polytechnic University Tianjin 300160 China

GaN epifilms are grown on the patterned sapphire substrates (PSS) (0001) and the conventional sapphire substrates (CSS) (0001) by metal-organic chemical vapor deposition (MOCVD) using a novel two-step growth. High resolution X-ray diffraction (HR-XRD) is used to investigate the threading dislocation (TD) density of the GaN epifilms. The TD density is calculated from the ω-scans full width at half maximum (FWHM) results of HR-XRD. The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2. which is less than on the CSS. This is confirmed by the results of atomic force microscopy (AFM) measurement. The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS. The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra. It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.

关键词： GaN patterned sapphire substrate threading dislocation XRD

Petrogenesis and significance of early Yanshanian syenite-granite complex in eastern Nanling Range

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Science China Earth Sciences 2005年第7期48卷 912-924页

作者： CHEN Peirong1, ZHOU Xinmin1, ZHANG Wenlan1, LI Huimin2. FAN Chunfang1, SUN Tao1, CHEN Weifeng1 & ZHANG Min1 1. State Key Laboratory of Mineral Deposits Research, Department of Earth Sciences, Nanjing university, Nanjing 2.0093, China 2. tianjin Institute of Geology and Mineral Resources, China Geological Survey, tianjin 300170, China State Key Laboratory of Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China tianjin Institute of Geology and Mineral Resources China Geological Survey Tianjin 300170 China

In the eastern Nanling Range there exists the early Yanshanian syenite-granite assemblage. A representative example is the Pitou-Tabei complex composed of the Tabei syenite pluton and the Pitou syenogranite pluton in southern Jiangxi Province. U-Pb zircon dating yields ages of 188.6±2.2.Ma for the Tabei pluton and 186.3±1.1 Ma for the Pitou pluton. The Tabei syenite is characterized by relatively low SiO2.content (62.40% - 68.75%), high alkalis (K2.+Na2. = 10.56%-11.96%), low percent K2./Na2. ratios (0.56-0.93), metaluminous fea- ture (A/CNK = 0.80-1.00), enrichment in LILE (Rb, Ba, K) and HFSE (Th, U, Nb, Ta, Zr, and so on), weakly negative to positive Eu anomalies (δ Eu = 0.63-1.82., relatively low (87Sr/86Sr)i (0.70412.0.70543), and relatively high ε Nd(t) (3.14-3.52.. The Pitou syenogranite is charac- terized by high silicon content (SiO2.= 71.06%-76.2.%), relatively low alkalis (K2.+Na2. = 8.10%-9.80%), high percent K2./Na2. ratios (1.2.-1.94), metaluminous feature (A/CNK = 0.94-1.07), enrichment in Rb, Th (U), K, depletion in Ba, Nb, Ta, Sr, P , Zr, Ti, high ΣREE (av- eraging 451.03 μg/g), strong negative Eu anomalies (δ Eu = 0.2.-0.33), relatively high (87Sr/86Sr)i (0.70805-0.70912., and relatively low ε Nd( t ) (?5.35-?6.2.). The Tabei syenite and Pitou syenogranite both have the characteristics of A-type granites. The former is considered to be from the asthenosphere mantle, and the latter was the product of the crust-mantle mixture. They both were probably formed in a rifting setting.

关键词： syenite-granite assemblage single zircon U-Pb age rifting environment Nanling Range.

Experimental study on high-voltage solar array sustained arc discharge induced by high charging

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Science China(Technological Sciences) 2007年第2期50卷 213-220页

作者： LI Kai1,2. XIE ErQing1, WANG Li2. LIU YanXia1, YANG Yang1, SUN YanZheng3, CUI XinYu3 & MAI ShengLi2.1 School of Physical Science and technology, Lanzhou university, Lanzhou 730000, China 2.Lanzhou Institute of Physics, Lanzhou 730000, China 3 {2. Institute of Power Source, {2. 300381, China 1. School of Physical Science and technology Lanzhou University Lanzhou 730000 China 2. Lanzhou Institute of Physics Lanzhou 730000 China 3. tianjin Institute of Power Source Tianjin 300381 China

It has been reported that sustained arc discharge induced by electrostatic discharge (ESD) could cause permanent damage to high-power and high-voltage solar array of spacecrafts. The paper focuses on ESD simulating experiments on Si and GaAs samples, and induces sustained arc discharge. The physical mechanism of sustained arc discharge is discussed by comparing the charging/discharging phenomena between Si and GaAs samples. The experiments show that sustained arc discharge can produce a permanent short-circuit channel between solar cell strings through which the solar array’s photovoltaic power may flow out sustainedly. The analyses show that sustained arc discharge strongly depends on solar array structure, solar array operating voltage, ESD characteristics and cell materials. Keywords high-voltage solar array - electrostatic discharge - sustained arc discharge - mechanism Supported by the National Laboratory of Vacuum, Cryogenics technology and Physics (Grant No. 51475030504DZ2.01), and the National High technology Development Program of China (Grant No. 2.02.A732.58)

关键词： high-voltage solar array electrostatic discharge sustained arc discharge mechanism