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3D virtual reconstruction of the Pleistocene cheetah skull from the Tangshan, Nanjing, china

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Progress in Natural Science:Materials International 2007年第1期17卷 74-79页

作者： DONG Wei, HOU Xinwen, LIU Jinyi, FANG Yingsan, JIN Changzhu and ZHU Qizhi ( institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, beijing 100044, china State Key Laboratory of Pattern Recognition, institute of Automation, Chinese Academy of Sciences, beijing 100080, china Nanjing Provincial Museum, Nanjing 210016, china Radiology Department, Renmin Hospital, Peking University, beijing 100044, china) [a]institute of Vertebrate Paleontology and Palecanthropology Chinese Academy of Sciences Beijing China [b]State Key Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing China [c]Nanjing Provincial Museum Nanjing China [d]Radiology Department Renmin Hospital Peking University Beijing China

The development of computer tomography and image processing has made it possible to establish virtual 3D reconstruction and non-invasive dissection of fossil specimens. We used these methods to reconstruct a virtual 3D skull of a Pleistocene cheetah skull from the Tuozi cave, Tangshan, Nanjing, and virtually dissected it for anatomic studies, and measured the volumes of different parts of the endocranium. The endocranium of the cheetah skull has showed that its frontal sinus is beehive-like, the frontal lobe of cerebra is relatively large but the temporal lobe is relatively small, its cerebral sulcus and gyrus are more complicated than those of the domestic cat, similar to those of the domestic dog, but simpler than those of giant panda, pig, cattle and horse. The technology of virtual 3D reconstruction and non-invasive dissection of fossil specimens can extend the morphological study from the exterior to the interior, and it can also help to study fragile specimens and virtually backup rare and precious specimens.

关键词： CT imaging 3D reconstruction cheetah skull early Pleistocene Tangshan Nanjing.

The Alternating-Direction Schemes and Numerical Analysis for the Three-dimensional Seawater Intrusion Simulation

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Acta Mathematicae Applicatae Sinica 2002年第3期18卷 389-404页

作者： Zhi-yue ZhangLASG, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china & School of Mathematics and computer Science, Nanjing Normal University, Nanjing 210097, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China School of Mathematics and computer Science Nanjing Normal University Nanjing China

Both numerical simulation and theoretical analysis of seawater intrusion in coastal regions are of great theoretical importance in environmental sciences. The mathematical model can be described as a coupled system of three dimensional nonlinear partial differential equations with initial-boundary value problems. In this paper, according to the actual conditions of molecular and three-dimensional characteristic of the problem, we construct the characteristic finite element alternating-direction schemes which can be divided into three continuous one-dimensional problems. By making use of tensor product algorithm, and priori estimation theory and techniques, the optimal order estimates in H1 norm are derived for the error in the approximate solution.

关键词： Three-dimensional seawater intrusion characteristic finite element alternating-direction optimal order estimate in H^1

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基于网络的设备镜像系统设计

计算机工程 2002年第6期28卷 190-191,221页

作者：谭毓安北京理工大学计算机科学与工程系北京100081

将镜像驱动程序挂接在系统上,截获源服务器中的读写操作,通过网络传输到目标服务器中,由目标系统执行相同操作。在源服务器和目标服务器中保持数据一致。该文讨论了系统中各模块的设计原理,以及同步和异步两种镜像方式。

关键词：设备镜像系统设计计算机网络数据安全

The (⊿+2,2)-incidence coloring of outerplanar graphs

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Progress in Natural Science:Materials International 2008年第5期18卷 575-578页

作者： Shudong Wanga,b,c, Jin Xu a,b, Fangfang Mac, Chunxiang Xua,b a institute of Software, School of Electronic Engineering and computer Science, Peking University, beijing 100871, china b Key Laboratory of High Con dence Software Technologies, Ministry of Education, beijing 100871, china c College of Information Science and Engineering, Shandong University of Science and technology, Qingdao 266510, china institute of Software School of Electronic Engineering and Computer Science Peking University Beijing 100871 China Key Laboratory of High Confidence Software Technologies Ministry of Education Beijing 100871 China College of Information Science and Engineering Shandong University of Science and Technology Qingdao 266510 China

An incidence coloring of graph G is a coloring of its incidences in which neighborly incidences are assigned di erent colors. In this paper, the incidence coloring of outerplanar graphs is discussed using the techniques of exchanging colors and the double inductions from the aspect of con guration property. Results show that there exists a (D + 2,2)-incidence coloring in every outerplanar graph, where D is the maximum degree of outerplanar graph.

关键词： Incidence coloring Incidence chromatic number Outerplanar graph

A new pseudorandom number generator based on a complex number chaotic equation

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Chinese Physics B 2012年第9期21卷 142-148页

作者：刘杨佟晓筠 School of computer Science and technology Harbin Institute of Technology

In recent years, various chaotic equation based pseudorandom number generators have been proposed. However, the chaotic equations are all defined in the real number field. In this paper, an equation is proposed and proved to be chaotic in the imaginary axis. And a pseudorandom number generator is constructed based on the chaotic equation. The alteration of the definitional domain of the chaotic equation from the real number field to the complex one provides a new approach to the construction of chaotic equations, and a new method to generate pseudorandorn number sequences accordingly. Both theoretical analysis and experimental results show that the sequences generated by the proposed pseudorandom number generator possess many good properties.

关键词： chaotic equation pseudorandom number generator complex number

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

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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, beijing 100084, china 2 Tsinghua National Laboratory for Information Science and technology, Tsinghua University, beijing 100084, china 3 Research institute of Information technology (RIIT), Tsinghua University, beijing 100084, 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

THE COMPOSABILITY PROBLEM OF THESEMANTICS OFXYZ/BE-COMMUNICATING PROCESSES

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Systems Science and Mathematical Sciences 1999年第S1期12卷 61-68,68-69页

作者： LI Guangyuan TANG Zhisong(Laboratory for computer Science, institute of Software, Academia Sinica,beijing 100080 china)

Composability is vital to the specification and verification of concurrent systems. This paper is devoted to the composability of XYZ / BE- communicating *** show that parallel composition processes preserve all of th... 详细信息

关键词： Linear temporal logic formal semantics communicating process parallelcomposition trace equivalence.

Study for ^(228)Th reduction in thermal reactor with Th-U fuel cycls

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Nuclear Science and Techniques 1999年第1期10卷 48-50页

作者： XU Xiaoqin (china institute of Atomic Energy, beijing 10241s) china institute of Atomic Energy Beijing 102413 China

By using computer code WIMS/CENDL, the effects of some parameters, core configuration such as fuel element structure, neutron flux and burn-up, are discussed in this paper. It is shown that high neutron flux, small fuel rod diameter, large volume ratio of coolant to fuel, seed-blank heterogeneous core arrangement and 231 Pa chemical separation are necessary for reducing 228Th production in reactor.

关键词：热反应堆钍-铀 228钍减少

Intelligent Intrusion Detection System Model Using Rough Neural Network

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Intelligent Intrusion Detection System Model Using Rough Neu...