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Mapping forest fire risk zones with spatial data and principal component analysis

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Science china(Technological Sciences) 2006年第Z1期49卷 140-149页

作者： XU Dong, Guofan Shao, DAI Limin, HAO Zhanqing, TANG Lei & WANG Hui institute of Applied Ecology, Chinese Academy of Sciences, shenyang 110016, china Graduate University of Chinese Academy of Sciences, Beijing 100039, china department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA department of management, shenyang institute of aeronautical engineering, shenyang 11003., china department of City Development, Jinan University, Jinan 250002, china institute of Applied Ecology Chinese Academy of Sciences Shenyang China Graduate University of Chinese Academy of Sciences Beijing China department of Forestry and Natural Resources Purdue University West Lafayette USA department of management Shenyang Institute of Aeronautical Engineering Shenyang China department of City Development Jinan University Jinan China

By integrating forest inventory data with remotely sensed data, new data layers for factors that affect forest fire potentials were generated for Baihe Forestry Bureau in Jilin Province of china. The principle component analysis was used to sort out the relationships between forest fire potentials and environmental factors. The classifications of these factors were performed with GIS, generating three maps: a fuel-based fire risk map, a topography-based fire risk map, and an anthropogenic-factor fire risk map. These three maps were then synthesized to generate the final fire risk map. The linear regression method was used to analyze the relationship between an area-weighted value of forest fire risks and the frequency of historical forest fires at each forest farm. The results showed that the most important factor contributing to forest fire ignition was topography, followed by anthropogenic factors.

关键词： wildfire risk, regression analysis, geographic information system, remote sensing, Baihe Forestry Bureau.

Influence of Hot Rolling Conditions on the Mechanical Properties of Hot Rolled TRIP Steel

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Journal of Wuhan University of Technology(Materials Science) 2008年第1期23卷 74-79页

作者：李壮 WU Di department of Materials engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

Influence of hot rolling conditions on the mechanical properties of hot rolled TRIP steel was investigated. Thermomechanical control processing （TMCP） was conducted by using a laboratory hot rolling mill, in which three different kinds of finish rolling temperatures were applied. The results show that polygonal ferrite, granular bainite and larger amount of stabilized retained austenite can be obtained by controlled rolling processes. The finer ferrite grain size is produced through the deformation induced transformation during deformation rather than after deformation, which affects the mechanical properties of hot rolled TRIP steel. Mechanical properties increase with decreasing finish rolling temperature due to the stabilization of retained austenite. Ultimate tensile strength （UTS）, total elongation （TEL） and the product of ultimate tensile strength and total elongation （UTS×TEL） reaches optimal values （791 MPa, 36% and 28 476 MPa%, respectively） when the specimen was hot rolled for 50% reduction at finish rolling temperature of 700 ℃.

关键词： hot rolling conditions retained austenite hot rolled TRIP steels mechanical properties

Mechanical Properties of DS NiAl/Cr(Mo) Alloys with Low Addition of Hf for High-temperature Applications

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Journal of Materials Science & Technology 2005年第5期 29-34页

作者： Xinghao DU1,2)+ and Jianting GUO1)1) institute of Metal Research, Chinese Academy of Sciences, shenyang 110016, china2) department of Materials engineering, shenyang institute of aeronautical engineering, shenyang 11003., china institute of Metal Research，Chinese Academy of Sciences，shenyang 110016，china department of Materials engineering，shenyang institute of aeronautical engineering，shenyang 11003.，china institute of Metal Research，Chinese Academy of Sciences，shenyang 110016，china

A multiphase NiAI-28Cr-5.85Mo-0.15Hf alloy, which was directionally solidified (DS) in an AI2O3-SiO2 mold by stan-dard Bridgman method and then underwent prolonged solution and aging treatment was prepared. The microstruc-ture, tensile properties as well as tensile creep of the heat-treated alloy at different temperatures were studied. Thealloy was composed of NiAl, Cr(Mo) and Hf-rich phase and small amount of fine Heusler phase (Ni2AIHf). Althoughthe present alloy exhibited high tensile strength at low temperature, it was weaker than that of system with highcontent Hf but still stronger than that of many NiAI-based alloys at high temperatures. The fracture toughness islower than that of DS NiAI-28Cr-6Mo alloy. Nevertheless, advantageous effects on the mechanical properties, *** decrease in brittle-to-ductile transition temperature (BDTT) were obtained for the low content of Hf. The ob-tained creep curves exhibit conventional shape: a short primary creep and long accelerated creep stages. The ruptureproperties of the heat-treated alloy follow the Monkman-Grant relationship, which exhibits similar creep behavior tothat of NiAI/Cr(Mo) system with high Hf content.

关键词： NiAI/Cr(Mo, Hf) alloys Microstructure Mechanical properties Tensile deformation Creep behavior

Control allocation and management of redundant control effectors based on bases sequenced optimal method

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Science china(Technological Sciences) 2010年第2期53卷 577-583页

作者： YANG LingYu1, FAN YanMing2, SHAO Shan2, ZHONG YouWu1 & SHEN GongZhang1 1 department of Automation Science and Electrical engineering, Beihang University, Beijing 100191, china 2 shenyang Aircraft Design and Research institute, shenyang 11003., china department of Automation Science and Electrical engineering Beihang University Beijing China shenyang Aircraft Design and Research institute Shenyang China

For an advanced aircraft, the amount of its effectors is much more than that for a traditional one, the functions of effectors are more complex and the coupling between each other is more severe. Based on the current control allocation research, this paper puts forward the concept and framework of the control allocation and management system for aircrafts with redundancy con-trol effectors. A new optimal control allocation method, bases sequenced optimal (BSO) method, is then presented. By analyz-ing the physical meaning of the allocation process of BSO method, four types of management strategies are adopted by the system, which act on the control allocation process under different flight conditions, mission requirements and effectors work-ing conditions. Simulation results show that functions of the control allocation system are extended and the system adaptability to flight status, mission requirements and effector failure conditions is improved.

关键词： aircraft with multiple control effectors flight control management

New development thoughts on the bio-inspired intelligence based control for unmanned combat aerial vehicle

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Science china(Technological Sciences) 2010年第8期53卷 2025-2031页

作者： DUAN HaiBin 1 ,SHAO Shan 2 ,SU BingWei 3 &ZHANG Lei 41 State Key Laboratory of Science and Technology on Holistic Flight Control,School of Automation Science and Electrical engineering, Beijing University of Aeronautics and Astronautics,Beijing 100191,china 2 Flight Control department,shenyang Aircraft Design and Research institute,shenyang 11003.,china 3 Beijing institute of Near Space Vehicle’s System engineering,Beijing 100076,china 4Integration and Project Section,Air Force Equipment Academy,Beijing 100085,china State Key Laboratory of Science and Technology on Holistic Flight Control School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing China Flight Control department Shenyang Aircraft Design and Research Institute Shenyang China Beijing institute of Near Space Vehicle’s System engineering Beijing China Integration and Project Section Air Force Equipment Academy Beijing China

Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of *** the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.

关键词： bio-inspired intelligence unmanned combat aerial vehicle(UCAV) artificial brain autonomous control bayesian network bio-inspired hardware heterogeneous cooperative control

RECRYSTALLIZATION TEXTURE INCOLD ROLLED Cu 30mass%Zn BRASS HEATED BY LASER BEAM

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Acta Metallurgica Sinica(English Letters) 1999年第4期12卷 664-667页

作者： Y.N.Wang1) , B.L.Wu2) ,L.Zuo1) and Z.D.Linag1) 1) department of Materials Science & engineering , Northeastern University ,shenyang 110006 ,china 2) shenyang institute of aeronautical engineering ,shenyang 11003. , china

Heating rate playsanimportantroleon recrystallizationtextureofcold deformed ***,thelaser heatingtechnique wasusedtotheultrarapidlyannealingon acold rolledCu 30 mass% Zn alloy. The experimental resultsshow thatthe texture development differs from those observed in the case of conventional annealing. When primary recrystallization completes,the grainsizeisvery fineandthegrain orientation distributionisalmostrandom . Withthecontinuousgrain growing,the dispersioncharacterofthegrainorientationsstillre mains. The possible mechanismson theevolution of ultrarapid recryctallization texture were discussed.

关键词： Cu 30 mass% Zn alloy recrystallization texture laser heating

THE PROPERTIES OF SILICA FUME-MAGNESIUM OXYCHLORIDE CEMENT MATERIALS

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1038-1040页

作者： H.F.Yu 1) ,P.Q.Liu 1) and W.H.Wang 2) 1) department of Materials Science and engineering, shenyang Architectural and Civil engineering institute,shenyang 110015,china 2) department of Airport, CAAC Eastnorth management, shenyang 110043,Chin

The properties of a new magnesium Oxychloride cement (MOC) material formed by silica fume uniformly mix in MOC paste was presents. The influence of silica fume on the water resistance and compressive strength of MOC paste was invesigated in this study. It is shown that when 30 weight percent of silica fume is added to the MOC paste, a high strength and water resisting new material with 112MPa compressive strength and 1 00 water resisting coefficient could by obtained.

关键词： silica fume magnesium oxychloride cement (MOC),compressive strength,water resistance

Modeling Production Planning System of BOM-based of Discrete Manufacture Enterprise

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Modeling Production Planning System of BOM-based of Discrete...

Static Properties Model of Magnetically Controlled Shape Memory Alloy Based on Neural Networks

2009中国控制与决策会议

作者： An Yu-xin School of Economy & management,shenyang institute of aeronautical engineering,shenyang 110136

＜正＞The product characteristics for discrete manufacturing enterprises are studied,the bill of materials（BOM） system is defined as the important product data in manufacturing system of discrete manufacture *** characteristics and the roles of EBOM,PBOM,MBOM connected with product data management are discussed and *** considering the balance production for production planning,some factors impacting production planning model and some critical problems are ***,a production planning model is established..

关键词： Discrete manufacture BOM Product data management Production planning

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Static Properties Model of Magnetically Controlled Shape Mem...