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Composition of sandstone and heavy minerals implies the provenance of Kuqa Depression in Jurassic, Tarim basin, china

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Progress in Natural Science:Materials International 2005年第7期15卷 633-640页

作者： WU Chaodong, LIN Changsong, SHEN Yanping and FENG Xue ( Key Laboratory of Orogenic Belts and Crustal Evolution, ministry of education, Peking university, beijing 100871, china Department of Resources, china university of Geosciences, beijing 100083, china) Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education Peking University Beijing 100871 China Department of Resources China University of Geosciences Beijing 100083 China

The petrological characteristics and heavy mineral assembly of the Jurassic System in Kuqa Basin are consistent with the tectonic evolution, which is the major factor controlling the filling process of Kuqa Basin. Controlled by the source areas at the both sides of the Basin, the matrixes are dominated by sedimentary rock, high-grade metamorphic rock, acid magmatic rock, and the highest heavy mineral assemblage of zircon-garnet-magnetite in the content. According to heavy mineral indexes, the Jurassic strata can be classified into three rhythmic units of heavy mineral. The lower sequence contains abundant heavy minerals and relatively high content of detritus and its matrixes primarily came form the recycling orogen. The assemblage of "zircon-garnet-magnetite" indicates that the sedimentary area in the early evolution period of the basin is relatively near the provenance. The middle sequence is different from the lower sequence in the heavy mineral assemblage and has the different characteristics from that of source rock. The heavy mineral assemblage is "garnet-zircon" with the highest content of garnet and its main matrices are the high-grade metamorphic rock, acid magmatic rock and hydrothermal vein at the northeastern edge of the basin. The middle and upper sequences are characterized by the clast provenance, which is primarily from the recycling orogen at the northern edge of the basin and secondarily from the southern uplift. As a result of the two provenances, the strata with apparent changes of heavy mineral assemblage and index better coincides with the interfaces of the secondary strata sequences, which reflects the denudation history and the filling process of the orogen at the northern edge of the basin.

关键词： sandstone components provenance analysis filling sequence tectonic evolution.

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Object-oriented World-view for Discrete-Event Simulation Modelling

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Systems Science and Systems Engineering 1996年第4期6卷 411-416页

作者： LIN Jian(The Management School beijing university of aeronautics & astronautics beijing 100083 china)

Object-oriented world-view provides a natural and powerful paradignl for expressing system elements and their dynamic behaviour for discrete-event simulation. Simulation gives the critical ability to study the dynamic behaviour of the models that are defined with object-voriented means. This paper first examines the ways of applying the object-oriented world-view to three major discrete simulation modelling approaches, then considers the process and merits of object-oriented simulation modelling.

关键词： Object orientation discrete-event simulation object-oriented modelling

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STIFFNESS EQUATION OF FINITE SEGMENT FOR FLEXIBLE BEAM-FORMED STRUCTURAL ELEMENTS

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Chinese Journal of Mechanical Engineering 2000年第1期13卷 17-24页

作者： Yun Chao Zong Guanghua (Institute of Robotics, beijing university of aeronautics and astronautics Liu Youwu (Tianjin university) 北京航空航天大学北京天津大学天津

The finite segment modelling for the flexible beam-formed structural elements is presented, in which the discretization views of the finite segment method and the difference from the finite element method are introduced. In terms of the nodal model, the joint properties are described easily by the model of the finite segment method, and according to the element properties, the assumption of the small strain is only met in the finite segment method, i. e., the geometric nonlinear deformation of the flexible bodies is allowable. Consequently,the finite segment method is very suited to the flexible multibody structure. The finite segment model is used and the are differentiation is adopted for the differential beam segments. The stiffness equation is derived by the use of the principle of virtual work. The new modelling method shows its normalization, clear physical and geometric meanings and simple computational process.

关键词： Beam-formed structural element Finite segment Stiffness equation Shape function

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INVESTIGATION ON FAULT DETECTION & DIAGNOSIS FOR POSITION SERVO SYSTEM OF AIRCRAFT ACTUATOR

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Chinese Journal of aeronautics 1997年第1期10卷 68-74页

作者： Zhang Jianhua Li Yunhua Wang Zhanlin Qiu Lihua(Faculty 303, beijing university of aeronautics and astronautics, beijing, china, 100083) Faculty 303 Beijing Univ. Aero. and Astronaut. Beijing 100083 China

A new approach to fault dignosis dealing with nonlinear system Hopfieldneural networks (HNN) is presented. The model parameters of the nonlinear systemtreated as functions of measured operating points and faults are estimated by HNN. Boththe nominal model of the healthy system and HNN training models corresponding to everyoperating point are recognized. In addition, the anticipated fault models corresponding toevery kind of fault and every operating point are obtaind in advance. The real systemmodel parameters of the system estimated by generalization process of HNN are matchedwith the nominal models of the healthy system and anticipated fault models. Consequent-ly, the final result of fault detection and diagnosis is acquired. The approach to fault diag-nosis is used in an aircraft actuating poisition servo system and the simulation resu1t is re-ported.

关键词： faults detection diagnosis nonlinear systems Hopfield neural networks(HNN) aircraft's actuating position servo systems

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SOME RESULTS ON GENERALIZED DIFFERENCE SETS

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Journal of Systems Science & Complexity 2008年第1期21卷 76-84页

作者： Xiwang CAO School of Mathematical Science, Nanjing university of aeronautics and astronautics, Nanjing 210016, china State Key Lab. of Information Security, beijing 100049, china. School of Mathematical Science Nanjing University of Aeronautics and Astronautics Nanjing China State Key Lab. of Information Security China

Sequences with ideal correlation functions have important applications in communications such as CDMA, FDMA, etc. It has been shown that difference sets can be used to construct such sequences. The author extends Pott and Bradley＇s method to a much broader case by proposing the concept of generalized difference sets. Some necessary conditions for the existence of generalized difference sets are established by means of some Diophantine equations. The author also provides an algorithm to determine the existence of generalized difference sets in the cyclic group Zv. Some examples are presented to illustrate that our method works.

关键词： Correlation functions diophantine equations generalized difference sets.

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Discrete　Simulation　Software　Styles　and　GPMS

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Systems Science and Systems Engineering 1997年第1期7卷 96-102页

作者： LIN Jian The Management School beijing university of aeronautics & astronautics, beijing,100083, china

GPMS is a new integrated simulation modelling environment for discrete event systems. It is composed of several independent components which perform different tasks in the process of simulation modelling and owns a number of features from different kinds of simulation software. This paper introduces GPMS through reviewing and discussing various discrete simulation software styles.

关键词： Simulation language Flow diagram Program generator VIS Object oriented

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A Discrete Event Simulation Support System in C^(++)

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Systems Science and Systems Engineering 1996年第4期6卷 456-464页

作者： LIN Jian(The Management School beijing university of aeronautics and astronautics beijing 100083, china)

This paper describes a discrete simulation support system that forms major parts of most simulation program. The support system contains three main features which differ from the most of other simulation support systems. It follows a strict three phase structure; supports visual interactive simulation. The principles of designing and implementing of the system are explained module by module.

关键词： discrete event simulation simulation support system C￣(++) three phase approach

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Study on Agent Based Methods for Concurrency Control in CSCW

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Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 495-499页

作者： Li Hu, Yao Shu zhen, Liu Chang hui Department of Computer Science, beijing university of aeronautics and astronautics, beijing 100083, china Department of Computer Science Beijing University of Aeronautics and Astronautics Beijing China

Concurrency control is a critical technology and one of the problems in CSCW systems. With the development of agent based technology, it has also been applied to research and development of CSCW systems. An Agent based method for concurrency control in CSCW is explored in this paper. This new way is achieved by making use of the thoughts of AOP (Agent Oriented Programming) to improve traditional locking method, on the basis of researching characteristics and functional requirements of concurrency control in CSCW, and analyzing various usually used concurrency control methods. All amendments to locking method are done on the basis of the analysis of limitations brought by locking. In this paper, a new algorithm supporting queue of locking request for Agent based concurrency control is also presented. All above aspects are discussed in some detail in this paper.

关键词： CSCW agent AOP Concurrency control algorithm supporting queue of locking request

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DYNAMIC FRACTURE TOUGHNESS OF ULTRASTRENGTH STEELS FOR AIRCRAFT

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Acta Metallurgica Sinica(English Letters) 1991年第3期4卷 209-213页

作者： XU Changgan ZENG Zhongping beijing university of aeronautics and astronautics,beijing,china

The plots of load vs deflection(P-D)for two ultra-strength steels 30CrMnSiNi2A and 300M has been examined on a Charpy impact tester with digital memory and microcomputer. A criterion was found to availably represent the dynamic fracture toughness,K_(Ic)~D ,of the steels under impact *** K_(Ic)~D,.can be calculated with suggesting that the turning point of change in compliance on the P-D plot is the point of destabilized crack *** K_(Ic)~D of steel 300M,quenched at 870℃ ,separately tempered at 300℃ and 450℃,was esti- mated to be 55—70 MN/m^(3/2)and 54—67 MN/m^(3/2)*** K_(Ic)calculated with accuracy about 20% seems to be available to the engineering evaluation.

关键词： ultra-strength steel impact toughness dynamic fracture toughness

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Experimental study on drying of typical MSW under incinerator-like conditions

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Science china(Technological Sciences) 2007年第5期50卷 636-643页

作者： ZHANG YanGuo1, CHEN MeiQian2, MENG AiHong1, LI QingHai1 & CHEN YunXuan2 1 Key Laboratory for Thermal Science and Power Engineering of ministry of education, Tsinghua university, beijing 100084, china 2 School of Mechanical, Electronical and Control Engineering, beijing Jiaotong university, beijing 100044, china Key Laboratory for Thermal Science and Power Engineering of ministry of education Tsinghua University Beijing China School of Mechanical Electronical and Control Engineering Beijing Jiaotong University Beijing China

In this paper, a series of experiments were conducted to investigate the drying of typical municipal solid wastes (MSW) in a muffle incinerator. From the experimental drying characteristic curves, the effects of temperature on drying process were observed to be more obvious in the low temperature region than in the high tem- perature region in muffle incinerator. At a specified drying temperature, drying time was highly dependent upon the packed waste thickness, having an exponent rela- tion with the thickness. When the drying temperature increased or the thickness of potato bulks was diminished, the maximum drying rate reduced. Based on the first-order reaction, activation energy (Ea), and factor A of potato and cabbage were determined.

关键词： drying, MSW, potato blocks, cabbage stems, temperature, dying rate

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