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CO observations of massive star forming regions at different evolutionary phases

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2, XU Ye1,3. SHEN Zhiqiang1,3.& LI Jingjing1,2 1. Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 20003., china 2. Graduate school of the Chinese Academy of Sciences, Beijing 10003., china 3. Joint Institute for Galaxy and Cosmology, Shanghai Astronomical Observatory and the University of Science and Technology of china, Shanghai 20003., china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China Graduate school of the Chinese Academy of Sciences Beijing China Joint Institute for Galaxy and Cosmology Shanghai Astronomical Observatory and the University of Science and Technology of China Shanghai China

The 12CO (J=1-0), 13.O (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of Purple Mountain Observatory. Of the observed 9 sources, 13.O cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2O masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 22566+5828 in the observing field of S152/S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2O maser simulta- neously.

关键词： star formation cloud core outflow H2O maser

A Way to Find All the Optimal Solutions in Linear Programming

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Journal of Systems Engineering and Electronics 2000年第2期11卷 11-16页

作者： Zuo Xiaode Xue Shengjia & Luo Lei(management school, Jinan University Guangzhou 51063., P. R. china) management school Jinan University Guangzhou 510632 P. R. China

With the expression theorem of convex polyhedron, this paper gives the general expression for the solutions in standard linear programming problems. And the calculation procedures in determining the optimal solutions ... 详细信息

关键词： Linear programming Convex polyhedron Optimal solution Simplex method

Diagnosis of iridovirus in large yellow croaker by PCR

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Acta Oceanologica Sinica 2003年第4期22卷 635-641页

作者： Chen Xinhua1, Wang Xiaowen2, Wu Wenzhong3.1. Third Institute of Oceanography, State Oceanic Administration, Xiamen 3.1005, china 2. school of Life Science, Xiamen University, Xiamen 3.1005, china 3. Fujian Entry-Exit Inspection and Quarantine Bureau of the People’s Republic of china, Fuzhou 3.0000, china Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China school of Life Sciences Xiamen University Xiamen 361005 China Fujian Entry-Exit Inspection/Quarant Fuzhou 350000 China

A rapid and sensitive PCR-based method for the detection of the large yellow croaker iridovirus (LYCIV) is described, which involves the amplification of a 295 bp fragment of the LYCIV ATPase gene from DNA isolated from naturally infected fish spleen. Sequencing of LYCIV ATPase gene fragment showed it shared 100% nucleotide sequence homology with the corresponding region of the ATPase gene of red sea bream iridovirus (RSIV) and sea bass iridovirus (SBIV), suggesting that LYCIV was homologous with RSIV and SBIV at least in part of the gemone. The specificity and sensitivity of the PCR procedure were tested on the iridovirus-infected fishes, the expected fragment was detected from spleen DNA samples of infected fishes, whereas no fragments were amplified from healthy fish spleen DNA, white spot syndrome baculoviruses (WSBV) DNA and pseudorabies virus (PRV) DNA. Detection limit of this method was 10(-7) ng positive plasmid DNA containing target sequence, equal to about 100 virions. In the infected experiment, first positive detection (1/4) appeared at Day 3.post-infection, all fish (4/4) tested positive at Day 7, however obvious symptoms were observed at Day 8, so LYCIV infection could be detected prior to the appearance of obvious symptoms. These results indicate that this PCR method could be used for early, rapid and specific detection of LYCIV infection.

关键词： large yellow croaker (Pseudosciaena crocea) iridovirus ATpase gene pCR

Statistical Inference for Simple Tree Order in the Means of Stochastic Order on Stratified Contingency Tables

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Wuhan University Journal of Natural Sciences 2010年第2期15卷 93-98页

作者： YAN Guoyi1,2, CHEN Jingjing3.1.school of Mathematics and Statistics, Wuhan University, Wuhan 43.072, Hubei, china 2. school of Sciences, Wuhan Institute of Technology, Wuhan 43.074, Hubei, china 3. school of Sciences, Wuhan University of Science and Technology, Wuhan 43.081, Hubei, china school of Mathematics and Statistics Wuhan University Wuhan China school of Sciences Wuhan Institute of Technology Wuhan China school of Sciences Wuhan University of Science and Technology Wuhan China

In this paper, we consider testing the hypothesis that all multinomial populations in the stratified contingency table are identically distributed against the alternative that all these popula- tions are in simple tree order. We provide an asymptotic represen- tation of the order-restricted maximum likelihood estimate of the unknown parameters. The resulting estimators are proven to be ~n-consistent and asymptotically normal under appropriate conditions. A chi-squared test method is used for this hypothesis test problem. A real data set is applied to illustrate our theoretical result.

关键词： simple tree order chi-squared test asymptotic representation asymptotic distribution

Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2), Xiuhua Sui~3. Linjing Xiao~3.1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education, china), Shandong University of Science and Technology, Qingdao 266510, P. R. china 2. school of Architecture, Tsinghua University, Beijing 100084, P. R. china 3. College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao 266510, P. R. china Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education China) Shandong University of Science and Technology Qingdao P. R. China school of Architecture Tsinghua University Beijing P. R. China College of Mechanical and Electronic Engineering Shandong University of Science and Technology Qingdao P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

Problems of Production management in Agile Manufacturing Environment and their Countermeasures

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厦门大学学报（自然科学版） 2002年第S1期41卷 239-240页

作者： CHEN Zhi-xiang (school of management, Zhongshan University, Guangzhou 510275, china)

Agile manufacturing is a new production mode. This pa per discusses the four problems of production management in the environment of a gile manufacturing, and some countermeasures are advanced: (1) Organization of production. Traditional MTO production or MTS production ca n not meet the requirement of agile manufacturing which request both high produc tivity and the manufacturing flexibility. For this, the paper advances best way is to use the production organization mode of MCP (Mass Customization Production ),and some strategies of MCP are discussed. (2) Production planning. The requirement of agile manufacturing to production pl anning embodies in two facets: synchronization and flexibility. The paper su ggests that the structure and function of MRPII system should be improved in ord er to meet the demand of agile manufacturing. (3. Production control. The problem of production control is how to reduce the u ncertainty of hand over time between enterprises and increase the production syn chronization level. The paper advances some research direction on improving production ability. (4) Quality control. The problems of quality management are how to transfer the information of customer’s quality requirement between different organizations an d how to keep the consistency and stability of quality. Some countermeasures are advanced. In the end of the paper, one case advanced administrates how to utilize the thou ghts of agile manufacturing to upgrade the competition ability.

关键词： agile manufacturing production management count er measures

Cloning and sequencing of nifBHDKENX genes of Paenibacillus massiliensis T7 and its nif promoter analysis

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Science china(Life Sciences) 2006年第2期49卷 115-122页

作者： ZHAO Hongxin1,2,3. XIE Baoen2 & CHEN Sanfeng1,2 1. State Key Laboratory for Agrobiotechnology and Biological school, china Agricultural University, Beijing 100094, china 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry, china Agricultural University, Beijing 100094, china 3. Chemical and Biological school, ShenYang Normal University, Shenyang 11003., china State Key Laboratory for Agrobiotechnology and Biological school China Agricultural University Beijing China Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry China Agricultural University Beijing China Chemical and Biological school ShenYang Normal University Shenyang China

A 3.4 bp of nifH fragment was PCR amplified from Paenibacillus massiliensis T7 using the universal degenerate primers. The PCR-amplified nifH fragment was labeled with DIG; then used as a probe in Southern blot analysis. Southern blot result showed that there were two positive signals, indicating that there might be two copies of nifH in P. massiliensis T7. A total of 10254 bp DNA sequence containing purD; nifBHDKENX was obtained by five rounds of inverse-PCR amplification. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ[54]-dependent promoter sequence was detected upstream of the nifB gene; nifBHDKENX were likely to be organized in one operon. Assays of β-galactosidase activity of P. massiliensis T7PB carrying a nifB-lacZ fusion under different concentrations of NH4 [+]; O2 showed that the expression of nifB-lacZ was strongly inhibited by O2.

关键词： Paenibacillus massiliensis T7, nifBHDKENX, nifB-lacZ, inverse-PCR.

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological Sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2, GU Yidong3. LIN Baojun3.& GUO Jiong3.1. Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100080, china 2. Graduate school of the Chinese Academy of Sciences, Beijing 10003., china 3. General Establishment of Space Science and Application, Chinese Academy of Sciences, Beijing 100080, china Correspondence should be addressed to L Congmin Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate school of the Chinese Academy of Sciences Beijing China General Establishment of Space Science and Application Chinese Academy of Sciences Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2 m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth Sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3. LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china 2. Institute of Geophysics, china Seismological Bureau, Beijing 100085, china 3. Institute of Deposition Resource, Chinese Academy of Geosciences, Beijing 10003., china 4. school of Exploration and Information, china University of Geosciences, Beijing 100083. china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Institute of Geophysics China Seismological Bureau Beijing China Institute of Deposition Resource Chinese Academy of Geosciences Beijing China school of Exploration and Information China University of Geosciences Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3.segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 40 km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.