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AN INVESTIGATION ON ASM TURBULENCE MODEL IN PREDICTIING NONISOTROPIC TURBULENT FLOWS

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Journal of Hydrodynamics 1991年第2期3卷 81-87页

作者： Yang Yong-quan Wu Chi-gong, chengdu university of Science and technology, chengdu Sichuar 610065, P.R.China chengdu Univ of Science and Technology Chengdu China

Non-isotropy is evident for flows with large streamline curvature. Algebraic stress model can fairly simulate non-isotropy of turbulence. Some flow situations were investigated with a well developed ASM model. The calcu- lated results show that the distributions of Reynolds stresses in different directions are obviously different. The non-isotropy of the flow is evident. The effect of streamline curvature on the flow feature of submerged water jet restricted by solid boundaries were studied, and its application in the design of energy dissipators of free trajectory jet type was disscused.

关键词： ASM AN INVESTIGATION ON ASM TURBULENCE MODEL IN PREDICTIING NONISOTROPIC TURBULENT FLOWS

AN ITERATION METHOD FOR INTEGRAL EQUATIONS ARISING FROM GRAVITY FLOWS WITH FREE SURFACE

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Acta Mechanica Sinica 1987年第2期3卷 123-138页

作者： Wen Xianyun Wu Chigong (chengdu university of Science and technology) 1. chengdu university of Science and technology Chengdu China

Gravity potential flows with free surface still present considerable difficulties in non-linear mathematical *** researchers using analytic function theory could consideronly simple geometrical *** curvilinear solid boundaries by means of analytictheory is a difficult problem that has not been *** this paper,using Muskhelishvili’s singularintegral equation theory,we turn the gravity flow problem into the Riemann-Hilbert *** the length of the streamline of the boundary as the independent variable and the velocitypotential of the boundary as the function to be determined,we avoid the difficulty that the angle ofthe curved fixed part is *** the difference method and the finite element method,we develop a new numerical method that is suitable for complex solid boundaries and overcome thedifficulties encountered in applying analytic function *** known discharge,the conver-g(?)nee and stability of the method have been proved and an estimation of error has been *** method has been successfully applied to the calculation of the flow past spillway *** values agree well with the measured results.

关键词： gravity flow with free surface complex variable function boundary-integral equation convergence stability estimation of error

Emergency assessment of seismic landslide susceptibility: a case study of the 2008 Wenchuan earthquake affected area

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Earthquake Engineering and Engineering Vibration 2009年第2期8卷 207-217页

作者： Tang Chuan,Zhu Jing and Liang Jingtao State Key Laboratory of Geo-Hazard Prevention,chengdu university of technology,chengdu 610059,China Professor Associate Professor Graduate Student State Key Laboratory of Geo-Hazard Prevention Chengdu University of Technology Chengdu 610059 China

The 8.0 Mw Wenchuan earthquake triggered widespread and large scale landslides in mountainous regions. An approach was used to map and assess landslide susceptibility in a given area. A numerical rating system was applied to five factors that contribute to slope instability. Factors such as lithology, topography, streams and faults have an important influence as event-controlling factors for landslide susceptibility assessment. A final map is provided to show areas of low, medium, and high landslide susceptibility. Areas identified as having high landslide susceptibility were located in the central, northeastern, and far south regions of the study area. The assessment results will help decision makers to select safe sites for emergency placement of refuges and plan for future reconstruction. The maps may also be used as a basis for landslide risk management in the study area.

关键词： landslide susceptibility GIS Wenchuan earthquake Qingchuan area

ISOTOPIC GEOCHRONOLOGY OF GRANITOIDS FROM THE NORTHWESTERN TIBET

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地学前缘 2000年第S1期7卷 215-216页

作者： Fan Ranxue (chengdu university of technology, chengdu 610059,China)

This study area is located in the western North Tibetan Plateau, lying between the western Kunlun Mountains to the north and the Gangdise Mountains to the south, and covers an area of about 230000km\+2. Granitoid rocks occur widely in the area and mainly consist of huge intermediate\|acid intrusive rock\|bodies, which locally are accompanied by ultrabasic to basic *** granite bodies from the locations were chosen for this study. Determinations of U\|Pb age on zircon and Rb\|Sr age on whole rock or mineral of these rock units were made using a Finnigan MAT\|261 mass spectrometer fitted with multi\|collector. The total procedural Pb,Sr blank were always in the 2～4 ng range and insignificant in comparison to the sample(milligram range). K\|Ar data were previously published and are reported again here in order to compare them with the Pb and Sr results. The results for the eight granite bodies reveal a complex age pattern. This area may be divided on the basis of these radiometric dates into 5 rock zones. These zones defined are, from north to south, the southern Kunlun, the Qiangtang, the Anglonggangri, the Gangdise and the Himalaya rock zones.

关键词： North Tibet granitoid isotopic geochronology

Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, China: Implication for ore genesis

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Science China Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1,2 & PAN Guitang2 1. Geoscience College, chengdu university of technology, chengdu 610059, China 2. chengdu Institute of Geology and Mineral Resources, chengdu 610082, China 1. Geoscience College Chengdu University of Technology Chengdu 610059 China 2. chengdu Institute of Geology and Mineral Resources Chengdu 610082 China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, China. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in China. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

Magnetic and dielectric properties of low temperature fired ferrite/ceramic composite materials

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Progress in Natural Science:Materials International 2011年第1期21卷 21-26页

作者： Wei-wei LING~(1,2),Huai-wu ZHANG~1,Ying HE~1,Yuan-xun LI~1,Yun-yan WANG~1 1.State Key Laboratory of Electronic Thin Films and Integrated Devices, university of Electronic Science and technology of China,chengdu 610054,China 2.Department of Communication Engineering,chengdu university of Information technology, chengdu 610225,China [a] State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu 610054 China [b] Department of Communication Engineering Chengdu University of Information Technology Chengdu 610225 China

Ni-Cu-Zn ferrite/CaTiO3and Ni-Cu-Zn ferrite/BaTiO3composites which can be applied in low temperature co-fired ceramic（LTCC） technology were synthesized by conventional solid-state reaction at temperature lower than 950℃.Influence of the microstructures and the gap parameterδ/D on the complex permeability of the above two composites was *** modifiedδ/D values of the above two composites show a good fit to the magnetic circuit *** dielectric properties of the composites were predicted by the Maxwell-Garnctt effective medium theory and the discrepancy between measured and calculated values was analyzed.

关键词： ferrite/ceramic composite low temperature co-fired ceramic(LTCC) solid-state reaction magnetic properties dielectric properties

Photonic band gap from periodic structures containing anisotropic nonmagnetic left-handed metamaterial

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Chinese Optics Letters 2010年第4期8卷 431-434页

作者：唐婷婷陈福深孙豹 Key Laboratory of Broadband Optical Fiber Transmission and Communication Networks in university of Electronic Science and technology of China Ministry of Education Department of Optoelectronic technology Chengdu University of Information Technology Key Laboratory of Broadband Optical Fiber Transmission and Communication Networks in university of Electronic Science and technology of China Ministry of Education

We demonstrate a photonic band gap（PBG） from one-dimensional（1D） periodic structures created by a double-layer unit cell with an air layer and an anisotropic nonmagnetic left-handed metamaterial（LHM） layer whose permittivity elements are partially *** requirements imposed on the materials and structures to realize a PBG are derived when the frequency is above or below the cutoff frequency,and the transmission properties of the PBG are discussed by utilizing 4×4 transfer-matrix method with dispersive semiconductor metamaterial.

关键词： Anisotropy Cutoff frequency Energy gap Metamaterials Photonic band gap Transfer matrix method

Geo-engineering Lessons Learned from the 2008 Wenchuan Earthquake in Sichuan and Their Significance to Reconstruction

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Journal of Mountain Science 2011年第2期8卷 176-189页

作者： HUANG Runqiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 Sichuan China

The 2008 Wenchuan earthquake in Sichuan of China was the result of quake-triggering along an active several hundred-kilometer-long fault. The subsequent landslides and debris flow geohazards are dominating factors in planning post-disaster recovery and rebuilding. This paper presents recommendations for coping with large-scale geohazards and disasters. It is essential to establish a national emergency management system for huge scale catastrophe and earthquake precursor identification. Town construction must be kept away from active faults, especially to improve town safety in areas with high risk of seismic and geological hazards, and it is important to improve geohazard investigation and remediation for mountain areas that have become loosened by earthquake activity. Geological factors must be better understood to reduce direct and secondary risks and effects of earthquakes. Site selections for public relocation require clear and informed analysis of geological and social risk reduction, so that relocation, infrastructure reconstruction, and commemorative relic-sites can be protected.

关键词： Wenchuan Earthquake Geohazard Reconstruction

Efficient Array Coding Scheme for Large-Scale Storage Systems

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Journal of Electronic Science and technology 2015年第2期13卷 102-106页

作者： Dan Tang Software Engineering College Chengdu University of Information Technology

A family of array codes with a maximum distance separable（MDS） property, named L codes, is proposed. The greatest strength of L codes is that the number of rows（columns） in a disk array does not be restricted by the prime number, and more disks can be dynamically appended in a running storage system. L codes can tolerate at least two disk erasures and some sector loss simultaneously, and can tolerate multiple disk erasures（greater than or equal to three） under a certain condition. Because only XOR operations are needed in the process of encoding and decoding, L codes have very high computing efficiency which is roughly equivalent to X codes. Analysis shows that L codes are particularly suitable for large-scale storage systems.

关键词： codes decoding dynamically parity restricted sector encoding operations running correcting