Science & Technology Review CONTENTS	Vol.25  No.23  2007 (Sum No. 245)
	This issue published on 10. Dec., 2007
Forward
1  The 21st Century Vision of Technological Innovation Evolution LU Yongxiang
News Round
7  When a Breakthrough is Created HUANG Yongming
Suggestion
8  Suggestion on Legislation of Sci-tech Input, and More
Special to S&T Review
17  History of China's Spaceflight: The Way to Tops in the Field ZHU Yu, WANG Zhi, QI Zhihong
Articles
23  Study on the Homoclinic Orbit Bifurcations in Pattern Formation System YUE Baozeng Abstract: Singular homoclinic stationary solutions and its bifurcations in the one-dimensional Gray-Scott model were carried out. A careful analysis of the scenario of the global bifurcation diagram suggests that the dynamics of self-replicating system is related to a hierarchy structure of folding bifurcation branches in parameter regions. The numerics suggests the Bogdanov-Takens points together with a presence of critical points emanating from the particular codimension-two homoclinic orbit play a central role for global bifurcation of periodic obits and the homoclinic solutions and the complex chaotic dynamics. Numerical simulation also reveals the existence of the modulating two-pulse or multi-pulse, which companying the procedure of pulse self-replicating in reaction-diffusion systems. Key Words: global bifurcation; pattern formation; homoclinic orbit; pulse solution CLC Numbers: N93, O19, O39  Document Code: A  Article ID: 1000-7857(2007)23-0023-05
28  Numerical Study on the Self-excited Vibration of Disc Brake System LI Bo, DING Qian, CHEN Yan Abstract: The dynamical equations for a 3-DOF automotive disc brake system are derived. The LuGre model is adopted to determine the friction force between the disc and the pad. The complex dynamical behavior of the brake pad with non-internal conditions is numerically investigated. It is shown that with the decrease of disc velocity, the tangential motion of the pad loses its stability, and the pure slip and incomplete-stick-slip self-excited vibrations are resulted. As the viscous friction factor becomes quite large, the chaotic motion with incomplete-stick-slip characteristics can be resulted. The pad can vibrate in torsion with high frequency when in incomplete-stick-slip stage. The tangential and the torsional self-excited vibrations lead to low and high frequency squeal noises. Key Words: brake system; dry friction; self-excited vibration; stick-slip CLC Numbers: TH113.1, O32  Document Code: A  Article ID: 1000-7857(2007)23-0028-05
33  Advances in Studies on the SD Oscillator and the Attractors CAO Qingjie, Marian Wiercigroch, Ekaterina Pavlovskaia, et al. Abstract: In this paper a new oscillator named the SD oscillator is proposed. The perturbed attractors are called the SD attractors. The dynamics of this oscillator depends on the smooth transition of a smooth parameter ?琢. The oscillator behaves smoothly if the parameter ?琢 is greater than zero and it behaves with discontinuity if ?琢＝0. This oscillator is of strong non-linearity and serves as an example of transition from smooth dynamics to that of discontinuity. The standard dynamics of double-well can be seen as a smooth system, similar to Duffing system. In addition to the standard dynamics, the discontinuous system behaves as non-standard dynamics, with so-called the saddle-like singularity and homoclinic-like orbit. Key Words: SD oscillator, SD attractor; Lypunov exponent; saddle-like equilibrium; homoclinic-like orbit CLC Number: O322  Document Code: A  Article ID: 1000-7857(2007)23-0033-05
38  Numerical Simulation for Time History of Stress Distributions in the Mortar During Explosive Lining WANG Hailiang, LI Xinming, DING Huizhe, et al. Abstract: Explosive lining process is numerically simulated by DYNA-2D finite element program, and the time history of stress distributions in the fluid mortar during explosive lining is analyzed. Analysis results indicate that, at the stage of stress oscillation, each mortar element oscillates not only in a lamellar way along the radial directions but also in a way of clustering along the tangential directions. In the initial stages, the fluid mortar elements oscillate mainly in the lamellar way along the radial directions. Each mortar element is subjected to the impact of the maximum compressive stress when the explosive is detonated and reaches its maximum pressure. Key Words: explosive lining; fluid mortar; stress; numerical simulation CLC Number: TD235  Document Code: A  Article ID: 1000-7857(2007)23-0038-04
42  Strength Analysis on High Speed Shaft Coupling SHENG Xuanyu, WANG Liankui Abstract: Shaft coupling is used in the power conversion unit of High Temperature Gas-cooled Reactor Gas Turbine (HTR-GT) system to connect the helium turbine and gear box. A three dimensional assemble model is built in the design software CATIA. The stresses in shaft coupling are calculated by ABAQUS for CATIA. The maximum Von Mises stress caused by centrifugal force is 303 MPa, that caused by bolt pre-tightening force is 167 MPa and that caused by moment of torque is 1 MPa. The first two maximum stresses occur at the bolt hole near the maximum outer diameter, so the total stress would be 470 MPa. Key Words: shaft coupling; stress; high rotation speed; high temperature gas-cooled reactor CLC Number: TL362  Document Code: A  Article ID: 1000-7857(2007)23-0042-04
46  Research and Application of Power-plant Fuel Audit Multi-dimension Data Analysis System Based on OLAP QIAN Li, QI Linhai Abstract: The current fuel management and the traditional fuel audit in power-plant are analyzed in this paper. The Power-plant Fuel Audit Multi-dimension Data Analysis System is proposed, based on OLAP multi-dimension data analysis, DBMS data transfer technology and the method of audit temporary table, which can be used to analyze the fuel data in multi-angles, multi-sides and multi-levels, and identify fuel audit trail and audit evidence among huge amount of data. The efficiency and quality of fuel audit are shown to be improved. Key Words: multi-dimension data analysis; OLAP; audit temporary table; DBMS; audit trail CLC Number: TP274.2  Document Code: A  Article ID: 1000-7857(2007)23-0046-05
51  Observations on the Microstructure of Uncinula necator Cleistothecia LI Hua, LAI Kanning, TAO Yongsheng, et al. Abstract: Some mature samples of Uncinula necator cleistothecia were observed and its morphology was studied in detail. Generally the mature concavo-convex cleistothecia are scattered on the surface of leaves, but sometimes they are clustered together. The diameter of cleistothecia is is in a range of 76.8~145 μm. The number of appendages per cleistothecium is 7~26, which is about 224.9~628.5μm in length, and 4.45~9.6 μm in width. The upper part of appendage is transparent, its base is dark brown, and the top curls up into one or two and a half circles. Each cleistothecium contains 3~6 asci, which are oval or near oval or near spheroid in shape and have a short handle in general, of a size in a range of (36.8~71.8) μm×(19.6~54.9) μm. The number of ascospore per ascus varies from 3 to 7, and they are colorless and oblong. Key Words: Vitis vinifera; Erysiphe necator; cleistothecia; microstructure description CLC Number: Q939.95  Document Code: B  Article ID: 1000-7857(2007)23-0051-04
55  Analysis for the Reinforcement Mechanism of Vegetation Root System in the Cracked Rock Slopes LU Dunhuan, WANG Xinghua Abstract: Ecological protection technique is a new technique for rock slope protection, and its reinforcement mechanism is not well studied. In view of applications of ecological protection technique of rock slope, this paper studies the reinforcement mechanism of ecological protection technique, mainly, the functions performed by the root system. The root system is analyzed, including the reinforcement mechanism of the deep root system of vegetation; the reinforcement mechanism of the shallow root system; the conservation of soil and water by the vegetation root system; and the zoological function of the vegetation root system; The calculation results may serve as a guidance for real projects. Key Words: vegetation root; slope; interaction mechanism; reinforcement system CLC Numbers: TU459, Q948.1  Document Code: A                Article ID: 1000-7857(2007)23-0055-04
59  Developing Ecological Economy of Sericulture and Vegetation Restoration in the Water-level-fluctuating Zone of the Three Gorges Reservoir HE Xiubin, XIE Zongqiang, NAN Hongwei, et al. Abstract: The water-level-fluctuating zone of the Three Gorges Reservoir performs important ecological functions for both the water body and land areas. Recently, severe environmental problems in the Three Gorges Reservoir area where the ecological environment is extremely fragile, become a focal point of local government's attention, and will greatly influence reservoir operation, water environment quality and production and life of people living there. In the present paper, the anti-season waterlogging resistance characteristics of mulberry is analyzed, and it is demonstrated that it is feasible to develop an ecological economy of sericulture in the Three Gorges area. A development model is proposed and its potentiality is analyzed to provide some guidances for policy making and practice in plant restoration in the water-level-fluctuating zone, environmental management and development of the rural economy in the Three Gorges Reservoir area. Key Words: Three Gorges Reservoir; water-level-fluctuating zone; plant restoration; sericulture; ecological economy CLC Number: S157.9  Document Code: A  Article ID: 1000-7857(2007)23-0059-05
Reviews
64  Current Development of Combinatorial Materials Approach for Fast Discovering and Screening of New Alloy Materials LIU Qian, CHEN Wei, LIU Qingfeng, et al.
69  Development in Marine Geography Information System WANG Fang, ZHU Yuehua
74  Experimental Study of Therapeutic Effect of Electro-acupuncture on Parkinson's Disease JIA Jun, LI Bo, SUN Zuoli, et al.
81  Notes on Reviews in Chinese Science Abstracts(Chinese Edition)
Science Reports
82  Meeting at the Interface: The Important Physical and Chemical Process of Fine Particulate
Commentary
85  Food Safety Calls for Organic Agriculture FENG Ying, WU Yishan
86  A True "Genius" LIU Bing
87  Books Appraisal
Editor-in-chief's Thoughts
89  How to Pound the Foundation of Postgraduates Successful Research Career (XV) FENG Changgen
Special Columns
6  Cover Story
9  Voice of Scientific Communit
10  Half-month News Briefs
12  International Journal Highlights
13  Domestic Journal Highlights
14  Scientific Community Briefs
16  Guidance for Contributors to Science and Technology Review
84  Events
88  Readers' Letters
90  Entertainment
92  Digest of Chinese Newspapers and Journals
93  Career
95  Global Jobs