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The CAD/CAM Solution and Realization for Machining Large Scale Steel-concrete Objects

厦门大学学报（自然科学版） 2002年第S1期41卷 14-15页

作者： ZHENG Yong-qian, CHEN Bing-sen, ZHANG Wei-min, FAN Liu-qun (department of Mechanical engineering, tongji university, shanghai 200092, china)

First the architecture of the integrated CAD/CAM system developed for machining large scale steel-concrete girders using I-DEAS and other developing tools are introduced; then the involved technologies in the development of the system are presented, which include the method for determining the position and orientation of the manufacturing features, the method for geometrical modeling of the girders, the techniques for generating the toolpaths for the 5-axis machining centers, the generative process planning technique and the postprocssing technique for the specific machines etc. Moreover some related special technical issues are also discussed. The CAD/CAM system is a network-based workshop-oriented manufacturing system, in which every machining cell can work independently serving two machining lines. The cell server take charge of the management of work schedules, personnel, machining resources, databases etc. the control computer serves to monitor the whole manufacturing lines, to arrange tasks, and to communicate; the two CAD/CAM workstations’ work is to model the girders using the CAD data, to plan the process and to generate the NC programs. The CL files that describe the toolpaths generated are ATP-format files. In order to translate them into NC codes that can be directly used by the 5-axis machining centers, a specific postprocessing program is developed for these distinct machines. The system has been successfully realized and applied in shanghai Maglev Transrapid project. In the developing process, the following technical problems are solved: 1. Algorithms for measuring, positioning, and machining complex objects. 2. Methods for Modeling. 3. Animation and postprocess techniques for 5-axis machining centers. 4. Technologies for machining large-scale concrete-steel structures Although further evolution is needed for this system, the facts have proven its performance satisfactory and the technologies and the methods developed suitable.

关键词： maglev transrapid CAD/CAM manufacturing feature Pseudo-NC Real-NC post process

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Lower Boundary of the Marine Pleistocene in Northern Shelf of the South china Sea

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Acta geologica Sinica(English Edition) 1991年第4期65卷 427-439,460页

作者： Wang Pinxian Xia Lunyu Wang Lujiang Cheng Xinrong department of Marine geology, tongji university, shanghai 200092,china Research Institute, Nanhai West Oil Corporation, Zhanjiang, Guangdong 524057, china 1 1) department of Marine geology Tongji University Shanghai 200092 China 2 2) Research Institute Nanhai West Oil Corporation Zhanjiang Guangdong 524057 China

A marine stratigraphic sequence across the Pliocene / Pleistocene boundary has been found in the north-ern continental shelf of the South china Sea. The marine Quaternary deposits in the Yinggehai Basin may ex-ceed 2,000 m in thickness, probably providing the best section for studying the lower boundary of the marinePleistocene in South china. The vertical succession with planktonic foraminifers and nannofossils revealed inboreholes in the basin has been well correlated with that in the international stratotype section of thePliocene / Pleistocene boundary at Vrica, Italy, resulting in the acquirement of a biostratigraphic boundary at1.64 Ma. This boundary, however, does not coincide with any prominent lithological palaeoenvironmentalchanges in the study area and can hardly be used in geological practice. There are, in contrast, significantchanges at the level of LAD of Globorotalia multicamerata sensu lato located below the above-mentionedboundary. The percentage of planktonic foraminifers in the total population and preservation of foraminiferaltests display great changes at this level corresponding to a clear onlap on the seismic profiles and indicating adepositional hiatus at ca. 2.0-2.5 Ma. Since the level can be widely traced in the Pearl River Mouth Basin andthe Beibu Gulf Basin and well corresponds with the marked depositional environmental changes recorded inthe west Pacific and other regions, it is recommended that the Plio / Pleistocene boundary be drawn at the levelof Gr. multicamerata sensu lato LAD, roughly concurrent with the Gauss / Matuyama turn.

关键词： Lower Boundary of the Marine Pleistocene in Northern Shelf of the South china Sea

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Efficient video cutout based on adaptive multilevel banded method

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Science china(Information Sciences) 2012年第5期55卷 1082-1092页

作者： CHEN MinGang 1,SUI BoCong 1,GAO Yan 2 & MA LiZhuang 1 1 department of Computer Science and engineering,shanghai Jiao Tong university,shanghai 200240,china 2 Software engineering Institute,East china Normal university,shanghai 200062,china 1. department of Computer Science and engineering Shanghai Jiao Tong University Shanghai 200240 China2. Software Engineering Institute East China Normal University Shanghai 200062 China

Although many efficient image cutout approaches have been proposed,it is still a challenge to cut out foreground objects from a video clip because of the costs of time and memory consumption and the difficulty in maintaining temporal coherence for the cutout *** this paper,we propose a novel and efficient video cutout approach by extending a multilevel banded image segmentation method to video *** our method,the segmentation results are propagated frame by frame at the lowest resolution level based on optical flow,and are refined in image pyramids level by level through banded graph *** construct an adaptive narrow band to ensure that the segmentation result falls exactly into the narrow band during *** results show that the video cutout approach based on adaptive multilevel bands dramatically reduces time and memory costs,and achieves ideal segmentation results.

关键词： video object cutout multilevel band graph cuts video segmentation

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Analytical layer-element solutions for a multi-layered transversely isotropic elastic medium subjected to axisymmetric loading

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Journal of Zhejiang university-Science A(Applied Physics & engineering) 2012年第1期13卷 9-17页

作者： Zhi-yong AI Nai-rui CANG Jie HAN Key Laboratory of geotechnical and Underground engineering of MOE Department of Geotechnical Engineering Tongji University Shanghai 200092 China department of Ciwl Environmental and Architectural Engineering The University of Kansas Lawrence KS 66045 USA

This paper presents an analytical layer-element method used to analyze the displacement of a multi-layered transversely isotropic elastic medium of arbitrary depth subjected to axisymmetric *** on the basic constitutive equations and the HU Hai-chang's solutions for transversely isotropic elastic media,the state vectors of a multi-layered transversely isotropic medium were *** the state vectors,an analytical layer element for a single layer(i.e.,a symmetric and exact stiffness matrix) was acquired in the Hankel transformed domain,which not only simplified the calculation but also improved the numerical efficiency and stability due to the absence of positive exponential *** global stiffness matrix was obtained by assembling the interrelated layer elements based on the principle of the finite layer *** solving the algebraic equations of the global stiffness matrix which satisfy the boundary conditions,the solutions for multi-layered transversely isotropic media in the Hankel transformed domain were *** actual solutions of this problem in the physical domain were acquired by inverting the Hankel *** paper presents numerical examples to verify the proposed solutions and investigate the influence of the properties of the multi-layered medium on the load-displacement response.

关键词： Transverse isotropy Analytical layer element Multi-layered elastic medium Axisymmetric loading Hankel transform

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Local connectivity of Julia sets for a family of biquadratic polynomials

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Science china Mathematics 2007年第10期50卷 1477-1492页

作者： Jing L~(1+) Wei-yuan QIU~2 ~1 department of Basic Education,shanghai Maritime university,shanghai 200000,china ~2 department of Mathematics,Fudan university,shanghai 200433,china 1. department of Basic Education Shanghai Maritime University Shanghai 200000 China 2. department of Mathematics Fudan University Shanghai 200433 China

The local connectivity of Julia sets for the family of biquadratic polynomials f_c(z)= (z^2-2c^2)z^2 with a parameter c is *** is proved that for any parameter c,the boundary of the immediately attracting domain of f_... 详细信息

关键词： biquadratic polynomials Julia sets local connectivity

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基于GML的GIS空间要素描述与应用研究

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同济大学学报（自然科学版） 2004年第6期32卷 749-754页

作者：童小华许谷声同济大学测量与国土信息工程系上海200092 同济大学经济与管理学院上海200092

以房屋土地地理信息系统 (GIS)中的地籍图形数据为例 ,探讨了基于地理标识语言 (GML)规范的空间要素描述 ,包括其数据描述结构和GML文档 ,并基于JAVA语言、文档对象模型和XML语言接口协议 (SAX)实现了一个基于GML的地籍GIS查询系统。

关键词：地理标识语言空间要素互操作

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Target tracking in wireless sensor networks using adaptive measurement quantization

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Science china(Information Sciences) 2012年第4期55卷 827-838页

作者： ZHOU Yan 1,2,LI JianXun 2 & WANG DongLi 1 1 Colleage of Information engineering,Xiangtan university,Xiangtan 411105,china 2 department of Automation,shanghai Jiao Tong university,shanghai 200240,china 1. Colleage of Information engineering Xiangtan University Xiangtan 411105 China2. Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

Quantization/compression is usually adopted in wireless sensor networks (WSNs) since each sensor node typically has very limited power supply and communication *** consider the problem of target tracking in a WSN with quantized measurements in this *** is focused on the design of measurement quantizer with adaptive *** on the probability density function (PDF) of the signal amplitude measured at a random location and by maximizing the entropy,an adaptive design method for quantization thresholds is *** to the nonlinear measuring and quantization models,particle filtering (PF) is adopted in the fusion center (FC) to estimate the target *** Cram'er-Rao lower bounds (CRLBs) for tracking accuracy using quantized measurements are also ***,a simulation example on tracking single target with noisy circular trajectories is provided to illustrate the effectiveness of the proposed approach.

关键词： target tracking wireless sensor network adaptive quantization posterior Cram’er-Rao lower bound

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Population-size-dependent branching processes in Markovian random environments

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Chinese Science Bulletin 1998年第8期43卷 635-638页

作者： WANG Hanxing 1 and DAI Yonglong 2 1. department of Mathematics, shanghai university, shanghai 201800, china 2. department of Mathematics, Zhongshan university, Guangzhou 510275, china department of Mathematics Shanghai University Shanghai China department of Mathematics Zhongshan University Gunngzhou China

A branching model {Z n} n≥0is considered where the offspring distribution of the population’s evolution is not only dependent on the population size, but also controlled by a Markovian environmental process {ξ n} n≥0. For this model, asymptotic behaviour is studied such as limn→∞Z n and limn→∞Z n/m n in the case that the mean m k, θof the offspring distribution converges to m>1 as the population size k grows to ∞. In the case that {ξ n} n≥0is an irreducible positive recurrent Markov chain, certain extinction (i.e. P(Z n=0 for some n)=1) and noncertain extinction (i.e. P(Z n=0 for some n)<1) are studied.

关键词： Markov chains in random environments stochastic population models branching processes.

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An optimal adaptive filtering algorithm with a polynomial prediction model

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Science china(Information Sciences) 2011年第1期54卷 153-162页

作者： TAN JiaJia & ZHANG JianQiu department of Electronic engineering,Fudan university,shanghai 200433,china 1. department of Electronic engineering Fudan University Shanghai 200433 China

A new approach to the optimal adaptive filtering is proposed in this *** this approach,a polynomial prediction model is used to describe the time-variant/invariant impulse response coeffcients of an identified *** the polynomial prediction model is viewed as the state equations of the identified impulse response coeffcients and the relationships between the inputs and outputs of the system are regarded as the measurements of the states,our adaptive filtering can be achieved in the framework of the Kalman filter. It is understood that Kalman filter is optimal in the sense of the MAP(maximum a posteriori),ML(most likelihood)and MMSE(minimum mean square error)under the linear and Gaussian white noise *** a result,our algorithm is also optimal in the statistical senses as Kalman filter does,provided that the impulse response coeffcients can be modeled by a *** only do the analytical results of the algorithm but also the simulation results show that our algorithm outperforms the traditional known algorithms.

关键词： adaptive filters polynomial prediction model impulse response coeffcients process equation Kalman filter optimal

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沥青路面面层和基层结构模量的反算

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同济大学学报（自然科学版） 2004年第10期32卷 1386-1389页

作者：张小宁孙立军同济大学交通运输工程学院交通工程系上海200092 同济大学交通运输工程学院道路工程系上海200092

分析了路面面层刚度对路表弯沉盆形状的影响 ,并在此基础上利用“惰性点”理论开发了一套反算路面面层和基层模量的方法 .通过大量理论分析和数值验证发现 ,当路面面层模量较大时 ,荷载作用下路表弯沉盆较坦 ;相反 ,当面层模量较小时 ,... 详细信息

分析了路面面层刚度对路表弯沉盆形状的影响 ,并在此基础上利用“惰性点”理论开发了一套反算路面面层和基层模量的方法 .通过大量理论分析和数值验证发现 ,当路面面层模量较大时 ,荷载作用下路表弯沉盆较坦 ;相反 ,当面层模量较小时 ,路表弯沉盆较陡 .利用这一特性 ,创造了一种新的反算路面模量的迭代方法 ,即利用惰性点方法反算得到的地基模量 ,匹配荷载中心点和附近校核点 2处的弯沉值 ,得到面层和基层的模量 .该方法过程收敛 ,且反算解唯一 .

关键词：沥青路面模量反算惰性点改进试算法弯沉盆

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