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Real-time reliability prediction for dynamic systems with both deteriorating and unreliable components

Science in china(Series F) 2009年第11期52卷 2234-2246页

作者： XU ZhengGuo1.2, JI YinDong2,3 & ZHOU DongHua1.2? 1.Department of Automation, tsinghua University, {1., china 2 tsinghua National Laboratory for Information Science and Technology, tsinghua University, {1., china 3 research Institute of Information Technology (RIIT), tsinghua University, {1., china Department of Automation Tsinghua University Beijing 100084 China tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China research Institute of Information Technology (RIIT) Tsinghua University Beijing 100084 China

As an important technology for predictive maintenance, failure prognosis has attracted more and more attentions in recent years. Real-time reliability prediction is one effective solution to failure prognosis. Considering a dynamic system that is composed of normal, deteriorating and unreliable components, this paper proposes an integrated approach to perform real-time reliability prediction for such a class of systems. For a deteriorating component, the degradation is modeled by a time-varying fault process which is a linear or approximately linear function of time. The behavior of an unreliable component is described by a random variable which has two possible values corresponding to the operating and malfunction conditions of this component. The whole proposed approach contains three algorithms. A modified interacting multiple model particle filter is adopted to estimate the dynamic system＇s state variables and the unmeasurable time-varying fault. An exponential smoothing algorithm named the Holt＇s method is used to predict the fault process. In the end, the system＇s reliability is predicted in real time by use of the Monte Carlo strategy. The proposed approach can effectively predict the impending failure of a dynamic system, which is verified by computer simulations based on a three-vessel water tank system.

关键词： reliability failure prognostics dynamic systems fault prediction particle filtering interacting multiple model exponential smoothing,predictive maintenance

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The multi-factor recombination and processes superimposition model for hydrocarbon accumulation:application to the Silurian in the Tarim Basin

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Petroleum Science 2008年第1期5卷 13-19页

作者： Meng Qingyang Pang Xiongqi Gao Jianbo State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China Basin and Reservoir research {1. China University of Petroleum Beijing 102249 China research {1. CNOOC Beijing 100027 China

The multi-factor recombination and processes superimposition model for hydrocarbon accumulation is put forward in view of the hydrocarbon geological characteristics of multiple episodes of structural evolution, multiple sets of source-reservoir-seal assemblage, multiple cycles of hydrocarbon accumulation and multiple episodes of readjustment and reconstruction in the complex superimposed basins in china. It is a system including theories and methods that can help to predict favorable exploration regions. According to this model, the basic discipline for hydrocarbon generation, evolution and distribution in the superimposed basins can be summarized in multi-factor recombination, processes superimposition, multiple stages of oil filling and latest stage preservation. With the Silurian of the Tarim basin as an example, based on the reconstruction of the evolution history of the four factors （paleo-anticline, source rock, regional cap rock and kinematic equilibrium belt） controlling hydrocarbon accumulation, this model was adopted to predict favorable hydrocarbon accumulation areas and favorable exploration regions following structural destruction in three stages of oil filling, to provide guidance for further exploration ofoil and gas in the Silurian of the Tarim basin.

关键词： Multi-factor recombination processes superimposition Tarim Basin Silurian favorable exploration region prediction

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An integrated decision method for prediction of tropical cyclone movement by using genetic algorithm

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Science china Earth Sciences 2005年第3期48卷 429-440页

作者： YANG Yuanqin1.& WANG Jizhi2 1. National Meteorological center, {1. 1.0081.china 2. Chinese Academy of Meteorological Sciences, {1. 1.0081. china 1. National Meteorological center 100081 Beijing China 2. Chinese Academy of Meteorological Sciences 100081 Beijing China

In this study an integrated decision method for the multi-prediction results of tropical cyclone movements by using genetic algorithm (GA) has been adopted. A genetic learning artifi- cial neural network (GLANN) as a learning mechanism for track prediction was developed through training with the huge samples of typhoon tracks from 1.84 to 2002. The prediction of typhoon motion is to consider how to suit the dynamic change of environment, where typhoon passed through. The neural network structure is described by GA. A fitness function for choice of GA is given to approach the maximum of fitness (the minimum of the errors). Parallel comparing analyses for prediction abilities of unusual typhoon tracks in recent years by GLANN with multi-forecast methods were conducted. More types of cases were employed in the comparing analyses, which consist of the typhoon, Winnie, No.1., in 1.97, characterized by a long life over the ocean and in the mainland with severe effect on china, the 1. unusual typhoon tracks in the 1.90s, the tracks with landfall and affected action in 1.98 and the typhoons born in the Northwestern Pacific and the South china Sea in 2000, including the 24—48 h forecast, etc. The results indicated that for prediction ability of typhoon tracks, specially for unusual typhoons, GA decision-making developed in this study is superior to the others.

关键词： genetic algorithm, integrated decision, prediction of tropical cyclone.

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Seismic wave propagating in Kelvin-Voigt homogeneous visco-elastic media

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Science china Earth Sciences 2006年第2期49卷 147-153页

作者： YUAN Chunfang1. PENG Suping1. ZHANG Zhongjie2 & LIU Zhenkuan3 1. china University of Mining & Technology, {1. 1.0083, china 2. Institute of Geophysics, Chinese Academy of Sciences, {1. 1.01.1. china 3. Exploration and Development research Institute of Daqing Oilfield, Daqing 1.371., china 1. china University of Mining & Technology Beijing 100083 China 2. Institute of Geophysics Chinese Academy of Sciences Beijing 100101 China 3. Exploration and Development research Institute of Daqing Oilfield Daqing 163712 China

This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.

关键词： Kelvin-Voigt visco-elastic velocity attenuation seismic wave.

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Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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Science china Earth Sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1.2,3,HUANG JiKun 1.3 & DENG XiangZheng 1.3 1.Institute of Geographic Sciences and Natural Resources research,Chinese Academy of Sciences,{1. 1.01.1.china 2 Department of Economics and Management,Zhejiang Forestry University,Linan 31.300,china 3 center for Chinese Agricultural Policy,Chinese Academy of Sciences,{1. 1.01.1.china 1. Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

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Study on Transformation of CaO-Al_2O_3-SiO_2-MgO System Inclusions in ZG06Cr1.Ni4Mo Stainless Steel

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Journal of Iron and Steel research International 2011年第S2期18卷 341-346页

作者： LIU Jian-hui1.3, DONG Han1.3, ZHU Rong2, LI Shi-qi2 (1. Institute for Structural Materials,Central Iron and Steel research Institute, {1. 1.0081.china 2. School of Metallurgical and Ecological Engineering,University of Science and Technology {1., {1. 1.0083,china 3. National Engineering research center of Advanced Steel Technology, {1. 1.0081.china) Cent Iron & Steel Res Inst Inst Struct Mat Beijing 100081 Peoples R China Univ Sci & Technol beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China Natl Engn Res Ctr Adv Steel Technol Beijing 100081 Peoples R China

This paper aims at generally studying on the inclusions of ZGG06Cr1.Ni4Mo ultra-low carbon stainless steel used for large scale hydraulic turbine sets. On the basis of analysis the industrial test samples, thermodynamic software FactSage is used to study inclusions transformation process in CaO-SiO2-Al2O3-MgO system while stainless steel is been smelting. The results illustrate the inclusions melting points and plasticity variation law. The reasonable inclusions plasticity controlling area is found out in low melting point. The melting point is up to 1.80℃ While MgO weight concentration is 1.% in CaO-SiO2-Al2O3-MgO system, SiO2, Al2O3 and CaO in inclusions are in weight concentration range of 50-70%, 1.-20% and 1.-40%, respectively. For purpose of gaining low melting point inclusions, silicon alumina radio in deoxidant should be controlled between 2-5 for ultra-low carbon stainless steel refining in industry.

关键词： ZG06Cr1.Ni4Mo stainless steel low melting point inclusion thermodynamic calculation

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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1.& LIU Changming1. 2 1. School of Environmental Sciences, beijing Normal University, beijing 1.0875, china 2. Institute of Geographic Science and Natural Resources research, beijing 1.01.1. china beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1.82—1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82 to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1.2, LU Yuanzheng1.2,3 & XU Daoyi4 1. research Institute of Petroleum Exploration and Development, {1. 1.0083, china 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, {1. 1.0083, china 3. china University of Geosciences, {1. 1.0083, china 4. Institute of Geology, china Earthquake Administration, {1. 1.0029, china 1. research Institute of Petroleum Exploration and Development 100083 Beijing China 2. Key Laboratory of Oil and Gas Reservoir of Petrochina 100083 Beijing China 3. china University of Geosciences 100083 Beijing China 4. Institute of Geology China Earthquake Administration 100029 Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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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 {1., Chinese Academy of Sciences, beijing 1.0080, china 2. Graduate School of the Chinese Academy of Sciences, beijing 1.0039, china 3. General Establishment of Space Science and Application, Chinese Academy of Sciences, beijing 1.0080, china Correspondence should be addressed to L Congmin 1. center for Space Science and Applied {1. Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China 3. General Establishment of Space Science and Application Chinese Academy of Sciences 100080 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.

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The coupling instability of Rossby and topographic Rossby waves in the equatorial area

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Science china Earth Sciences 2005年第10期48卷 1792-1801页

作者： CHAO Jiping1.2, LIU Lin1.3 & YU Weidong1.1. Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 266061. china 2. National {1. center for Marine Environmental Forecasts, State Oceanic Administration, beijing 1.0081. china 3. Ocean University of china, Qingdao 266003, china Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao china National research {1. for Marine Environmental Forecasts State Oceanic Administration beijing china Ocean University of china Qingdao china

In case of considering the fact that the tropical ocean thermocline or the lower at-mosphere height field has the meridional variation, the topographic Rossby wave will be excited. Also the background geostrophic current emerges. Under such conditions, the topographic Rossby wave can interact with the classical Rossby wave at some parameter band and thus brings a new kind of instability, which may be of potential application in understanding some phenomena of the ENSO cycle.

关键词： thermocline variation, equatorial jet, Rossby wave, topographic Rossby wave, coupling instability

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