18 February 2012, Volume 30 Issue 5
    

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    Articles
  • HUO Yan;LI Ping;HE Jiping
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    A study focused on the 3D gait analysis for the multiple sclerosis patients is designed. A 3D motion capture system is used to track the changes in gait performance involving the selected parameters before and after the treatment, and some changes of multiple gait parameters are successfully found. These changes reflect the subtle functional changes of the patients, and it is also found that the subtle functional changes are closely related to the treatment time. The quantities evaluation based on the gait data is able to compensate the disadvantages caused by the currently widely used evaluations. These objective assessments will assist the clinicians with making more effective treatment decisions and with facilitating new treatment development.
  • LUO Shouhua;CUI Yannan;BO Tengfei;LI Guang;CHEN Gong
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    The basic working principle of Cone Beam Computer Tomography (CBCT) is briefly described, the advantages and disadvantages of both continuous and pulsed X-ray imaging methods are analyzed, and the pulsed X-ray imaging method is adopted to implement the design of low-dose CBCT. On the basis of this, the internal and external trigger modes of PaxScan 2520 flat panel detector are realized. The experiment results show that the method of continuous X-ray imaging needs dozens of seconds for the process rotating a circle, in the meanwhile, the method of pulsed X-ray imaging only needs about four seconds for doing same job. In a word, pulsed X-ray imaging reduces the X-ray radiation time considerably and improves the safety performance of CBCT significantly. Besides, pulsed X-ray imaging with internal and external trigger modes has no difference in terms of image quality. The choice for the modes depends on whether or not needs active control for X-ray emission.
  • ZHANG Fengjun;ZHU Shuyang;ZHONG Shuang;SU Kejia;WEI Da
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    In order to ameliorate the inferior efficiency of manganese removal and the lengthy period of maturation concerned in the common filter medium, the filter media for manganese removal were prepared by modifying the original river sand The effects of hydraulic retention time, pH value, DO, and Mn2+ concentration on manganese removal efficiency were studied by the filtration test of simulation groundwater. The mechanism of manganese removal was also preliminarily discussed in the test. The results show that the Mn2+ concentration of effluent is constantly lower than 0.1mg/L, which conforms with the state standards for drinking water; under the optimum conditions, the water residence time is about 24min, the content of dissolved oxygen is about 7mg/L, the pH value of the inflow is neutral or alkaline, and the concentration of manganese is no more than 2mg/L. The membrane of modified river sand surface plays a crucial role. The mechanism of manganese removal that is adsorption and self-catalysis processes is preliminary confirmed based on scanning electron microscopy and X-ray spectrum analysis for the filtration membrane of modified river sand surface.
  • XIONG Lichun;CHEN Jianhong;SHI Dongping;YANG Libing;YANG Shan
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    Aiming at the current limitations of the City Emergency Response System (CERS), such as lack of system integration, uncentralized management, lower intelligence technology, and its accessibility to form the information isolated island, the related properties of the CERS's collaborative model are analyzed. Then, it is deemed to its properties, especially its cooperativeness, agree completely with the characteristics of the multi-agent. For this reason, based on the multi-agent technology, the system architecture of distributed CERS in the collaborative mode is proposed; the system is an integration of monitor, early warning, and rescue in CERS, and has more powerful perceptiveness, initiative, and self adaptability. Meanwhile, the structure of multi-agent systems is refined, and its structural model is sequentially established. Thus, on this basis, the course of information processing involving alarm receiving, analysis and judgment, and alarm processing is discussed in details. At the same time, based on the multi-agent system, its members and coordination between them in the system are considered. Finally, by using the blackboard model and contract net model, the coordination mechanism of CERS is studied. In addition, a comprehensive and collaborative operation control scheme on CERS is designed.
  • ZHANG Shuqin;SHAN Xinlan;DING Huirong;WANG Hongfu;ZHANG Lei
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    Meteorological conditions affect the yield and quality of plastic mulching-based table potato. In Shizuishan city, Ningxia Hui Autonomous Region,the analysis of correlation on yield and meteorological factors during growth stage shows the key factors affected potato production were the average minimum temperature in late March, the average minimum temperature May, the average minimum temperature early July, sunshine in early August and precipitation in June. The studies could provide some theoretical evidences for meteorological service of potato.
  • LI Wenqiang;LIU Xiao
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    Based on the idea of the divide and conquer method, as is commonly adopted in parallel algorithms, a grouping and order reducing sequence algorithm is proposed for solving the Toeplitz type circular tri-diagonal linear algebraic equation systems in this paper. Compared with the traditional algorithm for the same problem, the advantage of this grouping and order reducing algorithm is that the computation cost and the computer memory requirement can be reduced. The whole algorithm includes three steps. The first step is grouping and order reducing of the original system. To put it better, the coefficient matrix and the right hand side of a Toeplitz type circular tri-diagonal system of order n=μm is divided into μ subgroups. Consequently, the order of each subgroup is . The second step is the formation of the parameter equations. That is to say, according the characteristics of the tri-diagonal coefficient matrix, the relations between subgroups are obtained, and the solution components, which do not belong to the subgroups, are taken as parameters. Then, a parameter equation is formed based on the equation that includes the parameters. The third step is to solve the parameter equation. And then, the original system is solved by substituting the parameters into the corresponding subgroups. As for the tri-diagonal system, the grouping and order reducing algorithm can also reduce the requirement for the computer memory and increase the order of the system, but at the same time , increase the computation cost. Numerical experiments show that, on one hand, there is an optimal number for grouping in saving the computation cost if the order of the system is fixed. On the other hand, the optimal number for groupings increases with the increase of the order of the system.
  • WANG Xian;SONG Fang;FENG Qingwei
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    The concise synthesis of Erlotinib was described. Treatment of Ethyl 3,4-dihydroxybenzoate with 2-methoxyethyl methanesulfonate followed by nitration, reduction, cyclization and chloration to afford 4-chloro-6,7-bis(2-methoxyethoxy)-1,4-dihydroquinazoline, which was treated with 3-ethynylaniline and then with dry hydrochloride to give Erlotinib. In this synthesis, the nitration process has greatly been improved. The advantages of this synthetic route include short reaction time, good total yield, and simple work-up.
  • CHEN Qiang;ZHU Lin;AN Huiyong
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    Core-shell microgels were synthesized by the grafting polymerization of N-isopropylacrylamide in the presence of the polyvinylamine using TBHP as the initiator. The poly(vinyl alcohol)/microgel composite hydrogels were also prepared by the solution mixing and the frozen-thawing method. The morphology and the inner-structure of the microgels were characterized by SEM and TEM experiments. The temperature-sensitive properties of microgels and composite hydrogels were also investigated. The results show that the microgels are spherical and have a core-shell structure. The microgels and composite hydrogels have a nearly same volume phase transition temperature and the composite hydrogels show a rapid phase transition behavior.
  • Reviews
  • HAN Zaisheng;LI Yao;WANG Hao;HE Jing
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    Transboundary Aquifer (TBA) is an aquifer system that exists in more than one state. As an important component of the groundwater system, proper management and rational utilization in TBAs are significantly important for promoting sustainable development and good-neighbor relationships. The TBAs will not simply implicate by the country's political boundary as it follows the natural boundary lines. A brief count of the research on TBAs in the world is presented. Within the framework of the UNESCO's International Hydrological Program (IHP-VI & VII) activities for the International Shared Aquifer Resource Management (ISARM), the both preliminary and detail inventories on TBA in Asia has accomplished. Those TBAs are classified into two types, that is, regional grade and local grade. A draft of Asian TBAs map has advanced; the updated map provides the situation of the regional TBAs identifying as the actual shape. Two case studies have been conducted. Those are the TBAs in the middle Heilongjiang-Amur River and Lancang-Mekong River Basin. The UNESCO leading expert group has attempted with DPSIR framework for driving forces, pressures, state impact, and responses to classifications of TBAs. A TBA comprehensive evaluation indicators system is put forward. The potential benefits achieved in the case of TBAs depend on three sets of variables, namely, TBAs intrinsic value and functions, socio-economic, and legal indicators. With the legal and institutional indicators, the aquifers could be classified as inconsistent, less harmonious, harmonious, and more harmonious. Those are applied to the four TBAs in the Lancang-Mekong Basin. Countries with the TBAs should strengthen their cooperation for coordinative and joint management of groundwater resources in order to achieve sustainable utilization.
  • LIU Changxiao
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    The research and development of New Molecular Entities (NMEs) as new drugs is a long-term, systematic project involving multiple disciplines. The translation research recently proposed is able to build connection among basic laboratory research, preclinical studies, clinical evaluation and clinical application of new drug candidates to establish a novel development model, therefore, the R&D cycle can be shortened and the approval of new drugs for marketing will be promoted. Both in innovative research and clinical trials, pharmacokinetics and drug disposition (absorption, distribution, metabolism, excretion) properties are important criteria for assessing drug-likeness of candidates. Thus, pharmacokinetic study plays an important role in the translational research for the evaluation of NMEs throughout entire innovative drug R&D process. The pathways from bench to bedside and from bedside to the market in the course of the translational research are important strategy to improve efficiency, in which each step of R&D is associated with PK studies. Possibility of druggability of a certain chemical entity, early failure and early-out issues or success can be spotted at first place. Therefore, pharmacokinetics evaluation in drug discovery, drug design, research and development is valuable to improve the success rate and maintain low costs, and further access to safe, effective drugs for human beings.
  • WANG Ruili;LIU Quan;WU Zihui;HU Xiaomian
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    Adaptive grid method is one of the key techniques in the area of science and engineering applications. Based on the Lagrange grids of computational method, two types of different adaptive grid methods including couple adaptive mesh methods and pro-processor adaptive mesh methods are described. In the framework of couple adaptive mesh methods, several adaptive mesh methods including adaptive mesh refinement, moving mesh method, and adaptive coordinate methods are reviewed. In the framework of pro-processor adaptive mesh methods, adaptive mesh redistribution, reconnection-based method, changing connectivity of the mesh, and connectivity optimization method are described. Their advantages and disadvantages are compared with each other and analyzed with regard to the basic theory, efficiency, robustness for physics characteristics, and other features. It provides the support for using adaptive mesh method in the area of science and engineering applications.