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Adaptability of ESR dating of fault gouge in aseismic region:A case study on Hangzhou region, China

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Acta Seismologica Sinica(English Edition) 2008年第3期21卷 267-274,332页

作者：姚琪陈汉林张微叶建青刘静伟赵冬牛佳文廖林 Department of Earth Sciences Zhejiang University Engineering Seismology Institute of Zhejiang Province State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration

ESR dating has been widely used in seismic assessment. In this paper, we collected fault gouge samples systematically for ESR (Electron Spin Resonance) dating, and sediment samples of overlying strata, and offset strata for OSL (Optically Stimulated Luminescence) dating along Xiaoshan-Qiuchuan fault (XQF) trending NE-SW, Xiaofeng-Sanmen fault (XSF) trending NW-SE, and Changhua-Putuo fault (CPF) trending E-W. In the same fault outcrop, the ESR data of fault gouge is greater than the OSL data of the strata offset by fault. Therefore, the ESR data of fault gouge colleted in Hangzhou region do not represent the time of weak fault movement in Late Quaternary region, but represent the strong fault movements in Late Cenozoic. The episode of fault movement in Late Cenozoic could be speculated according to the ESR data: 1.000.58 Ma, there were strong fault movements along the XSF, XQF and CPF in Hangzhou region; 0.580.45 Ma, the fault movements of all faults became weaker and did not zero ESR signals significantly for ESR dating of fault movements; 0.450.20 Ma, there were strong fault movements along part of XQF; 0.10.01 Ma, there were fault movements along the XSF only, but the fault movements were not strong enough to reset the ESR signal; Since 0.01 Ma, the Hangzhou region tends to be stable. In addition, the XSF might be the division line of fault segmentation of XQF; there were strong fault movements along the southwest segment of XQF during 0.45 Ma to 0.20 Ma; while the fault movements along the northeast segment of XQF mainly occurred during 1.000.58 Ma.

关键词： fault gouge ESR dating fault activity Xiaoshan-Qiuchuan fault Hangzhou region

COMPUTATIONAL FLOW RATE FEEDBACK AND CONTROL METHOD IN HYDRAULIC ELEVATORS

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Chinese Journal of Mechanical Engineering 2005年第4期18卷 490-493页

作者： Xu Bing Ma Jien Lin Jianjie State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

The computational flow rate feedback and control method, which can be used in proportional valve controlled hydraulic elevators, is discussed and analyzed. In a hydraulic elevator with this method, microprocessor receives pressure information from the pressure transducers and computes the flow rate through the proportional valve based on pressure-flow conversion real time algorithm. This hydraulic elevator is of lower cost and energy consumption than the conventional closed loop control hydraulic elevator whose flow rate is measured by a flow meter. Experiments arc carried out on a test rig which could simulate the load of hydraulic elevator. According to the experiment results, the means to modify the pressure-flow conversion algorithm are pointed out.

关键词： Hydraulic elevator Computational flow rate Proportional valve

Optimal hardware/software co-synthesis for core-based SoC desi gns

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Journal of Systems Engineering and Electronics 2006年第2期17卷 402-409页

作者： Zhan Jinyu Xiong Guangze Coll. of Computer Science and Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P.R. China

A hardware/software co-synthesis method is presented for SoC designs consisting of both hardware IP cores and software components on a graph-theoretic formulation. Given a SoC integrated with a set of functions and a set of performance factors, a core for each function is selected from a set of alternative IP cores and software components, and optimal partitions is found in a way to evenly balance the performance factors and to ultimately reduce the overall cost, size, power consumption and runtime of the core-based SoC. The algorithm formulates IP cores and components into the corresponding mathematical models, presents a graph-theoretic model for finding the optimal partitions of SoC design and transforms SoC hardware/software co-synthesis problem into finding optimal paths in a weighted, directed graph. Overcoming the three main deficiencies of the traditional methods, this method can work automatically, evaluate more performance factors at the same time and meet the particularity of SoC designs. At last, the approach is illustrated that is practical and effective through partitioning a practical system.

关键词： SoC co-synthesis partition IP core software component optimal path.

SCC of X70 and Its Deteriorated Microstructure in Simulated Acid Soil Environment

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Journal of Materials Science & Technology 2009年第2期25卷 169-174页

作者： Zhiyong Liu Guoli Zhai Xiaogang Li Cuiwei Du Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China

In order to study the stress corrosion cracking （SCC） of X70 pipeline steel and its weld joint in acid soil environment of southeast of China, two simulating methods were used here. The one was to obtain the bad microstructures in heat affected zone by annealing at 1300℃ for 10 min and air cooling to room temperature, the other was to get a series of simulating solutions of the acid soil environment. SCC susceptibilities of X70 pipeline steels＇before and after being normalized in the simulated solutions were studied by slow strain rate test （SSRT） and microstructural observation of fracture areas. Potentiodynamic polarization curves were used to study the electrochemical behaviour of different microstructures. SCC does occur to both the as-received material and normalized microstructure after heat treatment as the polarization potential decreased. Hydrogen embrittlement （HE） is indicated occurring to all tested materials at -850 mV （vs SCE） and -1200 mV（vs SCE）. The SCC mechanisms are different within varying potential range. Anodic dissolution is the key cause as polarization potential higher than null current potential, and HE will play a more important role as polarization potential lower than the null current potential.

关键词： X70 steel Heat affect zone Stress corrosion cracking (SCC) Yingtan soil

Effect of Recycling in the HL-1M Tokamak

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Plasma Science and Technology 2004年第2期6卷 2185-2188页

作者：郑永真 Southwestern Institute of Physics Chengdu 610041 China

Tokamak plasma discharge disruption at high density is investigated. The instability analysis on model indicates that the disruption is resulted from the energy loss arising from hydrogen recycling on the edge of the plasma. This energy loss could lead to a contraction of the current channel and the production of a disruptively unstable configuration. Using a simple model we shall investigate the implications of recycling for *** critical high-density n ≤1.6× 1020m-3 is reached in LH-1H.

关键词： recycling disruption

Cretaceous desert cycles, wind direction and hydrologic cycle variations in Ordos Basin: Evidence for Cretaceous climatic unequability

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Science China Earth Sciences 2004年第8期47卷 727-738页

作者： JIANG Xinsheng PAN Zhongxi XIE Yuan LI Minghui Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Chengdu Institute of Geology and Mineral Resources CGSChengdu 610082China Chengdu Institute of Geology and Mineral ResourcesCGSChengdu 610082China Chengdu Institute of Geology and Mineral ResourcesCGSChengdu 610082China Chengdu Institute of Geology and Mineral ResourcesCGSChengdu 610082China

Climatic state under greenhouse effect is a currently hot point. Whether greenhouse climate in geological history, especially in Cretaceous, was equable or not has aroused extensive discussion. By analysis on depositional cyclcity, wind direction change and hydrologic cycle variation of Cretaceous desert in the Ordos Basin of China, the unequability of Cretaceous cli-mate is dealt. It is shown that Cretaceous climate was extremely cyclic, not only having long and mid term but also having strong seasonal even instantaneous changes. Therefore, it is sug-gested that Cretaceous climate was not equable.

关键词： Ordos Basin of China,Cretaceous desert cycle,wind direction change,hydrologic cycle variation,Cretaceous climatic unequability.

EXACT LINEARIZATION BASED MULTIPLE-SUBSPACE ITERATIVE RESOLUTION TO AFFINE NONLINEAR CONTROL SYSTEM

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Applied Mathematics and Mechanics(English Edition) 2006年第12期27卷 1665-1671页

作者：徐自祥周德云邓子辰 School of Electronics and Information Northwestern Polytechnical UniversityXi'an 710072P. R. China Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072P. R. China

To the optimal control problem of affine nonlinear system, based on differential geometry theory, feedback precise linearization was used. Then starting from the simulative relationship between computational structural mechanics and optimal control, multiple-substructure method was inducted to solve the optimal control problem which was linearized. And finally the solution to the original nonlinear system was found. Compared with the classical linearizational method of Taylor expansion, this one diminishes the abuse of error expansion with the enlargement of used region.

关键词： affine nonlinear system precise linearization multiple-substructure optimal control

Real-time simulation of ground displacement by digital accelerograph record

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Acta Seismologica Sinica(English Edition) 2005年第1期18卷 82-88页

作者：金星马强李山有 Institute of Engineering Mechanics China Earthquake Administration Nanjing University of Technology Nanjing 210009 China

With the development of accelerograph, strong ground motion data can be widely applied to many fields. Especially, it is an important milestone for strong motion observation to expand application fields into earthquake monitoring that real-time simulation of ground displacement can be obtained by strong motion records for determining three earthquake parameters. For the purpose of application, on the basis of principle of seismic response of single-degree-of-freedom (SDOF) system, this paper presents a suit of formula of simulating ground displacement records by using strong ground motion records with the help of simulator of SDOF system. The research results show that the technique is very efficient and can be widely applied to earthquake monitoring.

关键词： strong motion record SDOF system displacement simulation

Weight Data Fusion Based on Mutual Support Applied in Large Diameter Measurement

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 562-566页

作者： WANG Biao YU Xiaofen XU Congyu School of Instrument Science and Opto-electronic Eng＆eering Hefei University of Technology Hefei 230009 China

The on-line diameter measurement of larger axis workpieces is hard to achieve high precision detection, because of the bad environment of locale, the problem to amend the measuring error by non-uniform temperature field, and the difficulty to collimate and locate by usual method. By improving the measurement accuracy of larger axis accessories, it is useful to raise axis and hole＇s industry produce level. Because of the influence of complex environment in locale and some influential factors which are hard excluded from the large diameter measurement with multi-rolling-wheels method, the measurement results may not support or even contradict each other. To the situation, this paper puts forward a mutual support deviation distinguish data fusion method, including mutual support deviation detection and weight data fusion. The mutual support deviation detection part can effectively remove or weaken the unexpected impact on the measurement results and the weight data fusion part can get more accurate estimate result to the detected data. So the method can further improve the reliability of measurement results and increase the accuracy of the measurement system. By using the weight data fusion based on the mutual support （DFMS） to the simulation and experiment data, both simulation results and experiment results show that the method can effectively distinguish the data influenced by unexpected impact and improve the stability and reliability of measurement results. The new provided mutual support deviation distinguish method can be used to single sensor measurement and multi-sensor measurement, and can be used as a reference in the data distinguish of other area. The DFMS is helpful to realize the diameter measurement expanded uncertainty in 5 ×10^-6D or even higher when the measured axis workpiece＇s diameter is 1-5 m （ 1 m ≤ D ≤5 m ）.

关键词： multi-sensor mutual support weight factor data fusion rolling-wheel