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STUDY ON SINGULAR CONFIGURATIONS AND computer SIMULATION OF 6R ROBOT

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Chinese Journal of Mechanical engineering 2004年第2期17卷 177-180页

作者： Zhang Kai Hu Dejin Liu Chengliang school of Mechanical engineering,shanghai Jiaotong university,shanghai 200030, china school of Mechanical engineering Shanghai Jiaotong University 上海 200030

When robot is at singular configuration, the limited hand velocity wouldrequire some joints with infeasible speeds so as to lead unsafely of the system. A method of solvingthe approximate velocity of joint near singular configuration point by adding damped vector isproposed and a modified algorithm is provided. With the analysis of J^(-1) the singularconfigurations of 6R robot are divided into structure boundary singularity , boundary singularity ,inner singularity and wrist singularity. The conditions of singularities of the robot have beenascertained. The computer simulations of the singularities of the robot are developed, which havemany advantages over previous description methods of the singular configurations of robot. With thehelp of boundary singularity analysis, a application in welding trajectory planning checking of therobot has been carried out and the simulation result proved visualized and useful.

关键词： Robot Singular configuration computer simulation

Computational model for perception of objects and motions

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science china(Life sciences) 2008年第6期51卷 526-536页

作者： YANG WenLu1,2, ZHANG LiQing1 & MA LiBo1 1 Department of computer science and engineering, shanghai Jiao Tong university, shanghai 200240, china 2 Department of Electronic engineering, shanghai Maritime university, shanghai 200135, china Department of computer science and engineering Shanghai Jiao Tong University Shanghai China Department of Electronic engineering Shanghai Maritime University Shanghai China

Perception of objects and motions in the visual scene is one of the basic problems in the visual system. There exist 'What' and 'Where' pathways in the superior visual cortex, starting from the simple cells in the primary visual cortex. The former is able to perceive objects such as forms, color, and texture, and the latter perceives 'where', for example, velocity and direction of spatial movement of objects. This paper explores brain-like computational architectures of visual information processing. We propose a visual perceptual model and computational mechanism for training the perceptual model. The compu- tational model is a three-layer network. The first layer is the input layer which is used to receive the stimuli from natural environments. The second layer is designed for representing the internal neural information. The connections between the first layer and the second layer, called the receptive fields of neurons, are self-adaptively learned based on principle of sparse neural representation. To this end, we introduce Kullback-Leibler divergence as the measure of independence between neural responses and derive the learning algorithm based on minimizing the cost function. The proposed algorithm is applied to train the basis functions, namely receptive fields, which are localized, oriented, and bandpassed. The resultant receptive fields of neurons in the second layer have the characteristics resembling that of simple cells in the primary visual cortex. Based on these basis functions, we further construct the third layer for perception of what and where in the superior visual cortex. The proposed model is able to perceive objects and their motions with a high accuracy and strong robustness against additive noise. computer simulation results in the final section show the feasibility of the proposed perceptual model and high efficiency of the learning algorithm.

关键词： visual perception visual cortex computational model receptive fields simple cells complex cells

Smart home architecture based on event-driven DPWS～+

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Journal of shanghai university(English Edition) 2011年第5期15卷 386-390页

作者：陈鹏支小莉 school of computer engineering and science Shanghai University

With the advances of electronic information technology and computer network, especially the embedded technology, smart home is no more just a vision but being practical. The interoperability of heterogeneous devices and flexibility of devices＇ usage are two key problems that challenge the implementation of smart home. To deal with these two issues, this paper proposes an event-driven service oriented architecture using device profile for web services （DPWS）. DPWS inherits the advantages of the traditional web services in achieving interoperability without dependence on platform, while improving service discovery and security as well as being optimized for deploying on resource constrained devices. By providing a visual interface for describing a service workflow （SW）, the user can easily customize the actions of devices by services composition. Devices automatically cooperate without user＇s intervention to complete required business logic. This is achieved by fully exploiting the eventing capabilities on DPWS enabled home devices. Finally, a home theater scenario is given to illustrate the event driven mechanism for the SW in the proposed smart home framework.

关键词： device profile for web services (DPWS) smart home event-driven service workflow (SW)

Model Checking-Based Testing of Web Applications

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Wuhan university Journal of Natural sciences 2007年第5期12卷 922-926页

作者： ZENG Hongwei MIAO Huaikou school of computer engineering and science Shanghai University Shanghai 200072 China

A formal model representing the navigation behavior of a Web application as the Kripke structure is proposed and an approach that applies model checking to test case generation is presented. The Object Relation Diagram as the object model is employed to describe the object structure of a Web application design and can be translated into the behavior model. A key problem of model checking-based test generation for a Web application is how to construct a set of trap properties that intend to cause the violations of model checking against the behavior model and output of counterexamples used to construct the test sequences. We give an algorithm that derives trap properties from the object model with respect to node and edge coverage criteria.

关键词： Web application test generation model checking consistency relation

Influence of rare earth promoters on the performance of Ni/Mg(Al)O catalysts for hydrogenation and steam reforming of toluene

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Rare Metals 2009年第6期28卷 582-589页

作者： ZHANG Yuwen CHENG Hongwei LU Xionggang DING Weizhong ZHOU Guozhi shanghai Key Laboratory of Modem Metallurgy and Materials Processing School of Materials Science and Engineering Shanghai University Shanghai 200072 China school of Metallurgical and Ecological engineering University of Science and Technology Beijing Beijing 100083 China

CeO2-, La2O3-, and ZrO2-promoted Ni/Mg（Al）O catalysts synthesized by hydrotalcite-type precursors have been investigated with respect to catalytic activity and carbon formation in the hydrogenation and steam reforming of toluene as a model tar compound. X-ray diffraction （XRD）, Brunauer-Emmett-Teller （BET） specific surface area and Hz-temperature programmed reduction （TPR） were used to observe the characteristics of the prepared catalysts. The carbon formation and its amount on the used catalysts were examined by transmission electron microscope （TEM）, scanning electron microscope （SEM） and thermogravimetric （TG）. The trend of catalytic activity as derived from the experimental results followed the order： Ni-Ce〉Ni-La〉Ni-Zr〉Ni. The catalyst modified with CeO2 exhibited the highest catalytic performance and had good carbon resistance in the hydrogenation and steam reforming of toluene. A toluene conversion of 96.8%, a CH4 yield of 45.2% and a CO yield of 50.4% have been achieved. The addition of promoters led to better dispersion of nickel species and higher interaction nickel-support, which were favorable for increasing the catalytic activity and effectively preventing carbon formation.

关键词： hydrogen production hydrogenation rare earth hydrotalcite

NEAR WAKE OF A MODEL HORIZONTAL-AXIS WIND TURBINE

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Journal of Hydrodynamics 2009年第2期21卷 285-291页

作者： HU Dan-mei DU Zhao-hui school of Power and Enviromental engineering Shanghai University of Electric Power Shanghai 200090 China school of Mechanical engineering Shanghai Jiao Tong University Shanghai 200240 China

An experimental investigation on the properties of the near wake behind the rotor of a Horizontal-Axis Wind Turbine （HAWT） was carried out at model scale. Measurements were made with a stationary slanted hot-wire anemometer using the technique of phase-locked averaging. The primary aim is to study the formation and development of the three-dimensional wake. Five axial locations were chosen within four chord lengths of the blades over a range of tip speed ratios. The results show that during the downstream developmerit of the wake, the wake centre traces a helical curve with its rotation direction opposite to that of the rotor. The distribution of mean velocity behind the HAWT rotor reveals an expansion and a decay of the three-dimensional wake. The shapes of the mean velocity distribution are similar along the blades span at the same downstream axial location. It is shown that the turbulence levels in the wake are higher than those in the non-wake region. The circumferential component and the radial component of the turbulence intensity are higher than the axial component. Our study offers some food of thought for better understanding of the physical features of the flow field as well as the performance of HAWT.

关键词： horizontal-axis wind turbine wake flow hot-wire anemometry experimental

Deadlock detection using abstraction refinement

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Journal of shanghai university(English Edition) 2010年第1期14卷 1-5页

作者：曾红卫 school of computer engineering and science Shanghai University

This paper adopts counterexample guided abstraction refinement scheme to alleviate the state explosion problem of deadlock detection. We extend the classical labeled transition system models by qualifying transitions as certain and uncertain to make deadlock-freedom conservative, i.e. if the abstraction of a system is deadlock-free, then the system is deadlock-free. An abstraction refinement approach to deadlock detection is proposed, and the correctness of the approach is proved.

关键词： deadlock detection state explosion extended labeled transition system abstraction refinement counterexample

Excavation and characterization of refuse in closed landfill

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Journal of Environmental sciences 2002年第3期14卷 303-308页

作者： ZHAO You cai (The State Key Laboratory of Pollution Control and Resource Reuse, school of Environmental science and engineering, Tongji university, shanghai 200092, china. ) The State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and EngineeringTongji UniversityShanghai 200092China E-mail:zyclmk @ online***

Refuse in landfills becomes stabilized as organic matter in refuse degrades and soluble inorganic substances dissolve during their long term stabilization process. In this paper, this process is also referred to as mineralization process and the resultant stabilized refuse referred to as aged refuse. Aged refuse contains a wide spectrum and huge quantity of microorganisms with strong decomposition capability for refractory organic matter present in some wastewater such as leachate. In this study, aged refuse excavated from 2 to 10 years old closed landfill compartments in shanghai Refuse Landfill is characterized in terms of particulate distribution by screening, total nitrogen, total phosphorus, biodegradable matter. The approaches for redevelopment of both land and aged refuse in the stabilized landfills are proposed.

关键词： landfill refuse mineralization

Seamlet carving for shape-aware image resizing

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science china(Information sciences) 2012年第5期55卷 1073-1081页

作者： LIN Xiao 1,2,SHENG Bin 1,MA LiZhuang 1,SHEN Yang 1 & CHEN ZhiHua 3 1 Department of computer science and engineering,shanghai Jiao Tong university,shanghai 200240,china 2 Academy of Information Technology,Luoyang Normal university,Luoyang 471022,china 3 Department of computer science and engineering,East china university of science and Technology,shanghai 200237,china Department of computer science and engineering Shanghai Jiao Tong University Shanghai China Academy of Information Technology Luoyang Normal University Luoyang China Department of computer science and engineering East China University of Science and Technology Shanghai China

In this paper we propose an optimized seam-carving approach for anti-shearing image *** image/video seam-carving strategy only focuses on deleting the pixels along 8-connected seams,which may lead to the obvious information loss during *** the traditional seam-carving methods,our approach can construct a seamlet to handle the discontinuous pixels and further achieve an optimized image resizing results with *** particular,to suppress zigzag artifacts,we introduce the anti-shearing energy into the seamlet generation,which includes two steps:1) the energy map is formalized by using Gabor filtering and the saliency map;2) The energy computation is optimized in Gabor feature space to obtain the resizing results without the connectivity *** experimental results and comparisons show the effectiveness of our method.

关键词： image resizing seamlet carving saliency map