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Parallel-pipelined Architecture of H.2.4 Deblocking Filter with Adaptive Dynamic Power

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Journal of shanghai jiaotong university(Science) 2010年第2期15卷 224-230页

作者：韦虎林涛 department of electronic {2. Shanghai Jiaotong University Institute of Very Large Scale Integrated Circuits Tongji University

In H.2.4,the computational complexity and memory access of deblocking filter are variable and depend on the video contents. In this paper,a pipelined VLSI architecture of deblocking filter with adaptive dynamic power is proposed. It avoids redundant computations and memory access by precluding the blocks which can be skipped. And the vertical and horizontal edges are simultaneously processed in an advanced scan order to speed up the decoder. As a result,the dynamic power of the proposed architecture can be reduced (up to about 89%) adaptively for different videos. And the off-chip memory access is improved compared to the previous designs. Moreover,the processing capability of the proposed architecture is very appropriate for real-time deblocking of high-definition television (HDTV,192.× 1080 pixel/frame,30 frame/s video signals) video operation at 38 MHz,which significantly outperforms the previous designs from 1.2. times to 4.8 times.

关键词： deblocking filter adaptive dynamic power parallel processing pipeline H.2.4

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, {2. Jiao Tong university, shanghai 2.02.0, China 2.department of electronic engineering, {2. Maritime university, {2. 2.0135, China 1. department of Computer Science and engineering Shanghai Jiao Tong University Shanghai 200240 China 2. department of electronic {2. Shanghai Maritime University Shanghai 200135 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

An analytical model for SMAC protocol in multi-hop wireless sensor networks

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Science China(Information Sciences) 2010年第11期53卷 2323-2331页

作者： LUO Jun, JIANG LingGe& HE Chen department of electronic {2., shanghai jiaotong university, shanghai 2.02.0, China 1. department of electronic {2. Shanghai Jiaotong University Shanghai 200240 China

Considering the active/sleep dynamics and the contention backoscheme of SMAC protocol in multi-hop wireless sensor networks (WSNs), we model each node as a finite single server queue with server shutdown, and model each node’s states as a two-dimensional continuous-time Markov chain. Based on the model, we derive the network performance in terms of average packet loss ratio, network throughput, average packet delay and average power consumption. Experiment comparisons show that the analytical results match well with the simulation results, which validates the accuracy of the analytical model. Furthermore, using the analytical model can enable us to investigate the performance tradeobetween energy efficiency and QoS requirement, and give us theoretical insight into the optimal parameters such as duty cycle, mean active period and buffer size in multi-hop wireless sensor networks.

关键词： multi-hop wireless sensor networks Markov chain energy efficiency QoS

Spatial continuity incorporated multi-attribute fuzzy clustering algorithm for blood vessels segmentation

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Science China(Information Sciences) 2010年第4期53卷 752-759页

作者： HAO JuTao1*, ZHAO JingJing2.& LI MingLu3 1School of Optical-Electrical and Computer engineering, university of {2. for Science and Technology, {2. 2.0093, China 2.4} of Electrical engineering, {2. university of Electric Power, {2. 2.0090, China 3department of Computer Science and engineering, shanghai jiaotong university, {12., China 1. School of Optical-Electrical and Computer engineering University of Shanghai for Science and Technology Shanghai 200093 China2. Department of Electrical Engineering Shanghai University of Electric Power Shanghai 200090 China3. Department of Computer Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

A three-dimensional representation of vasculature can be extremely important in image-guided neurosurgery, pre-surgical planning. In this paper, a spatial continuity incorporated multi-attribute fuzzy clustering algorithm (MAFCM S) is proposed to segment entire blood vessels from TOF MRA images. This clustering method takes both the intensity information and the geometrical information into account, while most of the cur- rent clustering methods only deal with the former. In this method, a new dissimilarity measure, which integrates the intensity and the geometry shape dissimilarity, is introduced. Because of the presence of the geometrical information, the new measure is able to differentiate the pixels with similar intensity values within different geometrical shape structures. Experimental results show that the new algorithm can get better segmentation.

关键词： fuzzy c-means clustering scale space analysis spatial continuity blood vessel segmentation multi-attribute fuzzy clustering

Effect of Solute Drag and Precipitate Pinning on Austenite Grain Growth in Ti-Nb Microalloyed Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 383-387页

作者： FU Li-ming 1,WANG Huan-rong 2.WANG Wei 2.SHAN Ai-dang 1 (1.School of Materials Science and engineering,shanghai jiaotong university,{2.,China 2.department of Structural Steels,Baosteel Research Institute,shanghai 2.1900,China) shanghai Jiao Tong Univ Sch Mat Sci & Engn Shanghai 200240 Peoples R China Baosteel Res Inst Dept Struct Steels Shanghai 201900 Peoples R China

A metallurgical model concerning the co-effect of the Nb solute drag and the complex carbonitride precipitates pinning is proposed to predict the recrystallization austenite grain growth of low carbon Nb-containing microalloyed *** analysis,both predicted and experimental,reveals the precipitate pinning plays a dominate role in suppressing the austenite grain growth with less Nb solute drag effect in high temperature region whereas the Nb solute drag predominates in relatively low temperature region.A factor p is suggested to assess the effectiveness of drag and *** pinning and the drag are more effective in restraining grain growth as p>0 and p<0,respectively.A low carbon Nb microalloyed steel and a kind of Ti-modified low carbon Nb steel by Ti substituting for part of Nb are employed to validate the modeling *** theoretical calculations show a good agreement with experimental results.

关键词： grain growth precipitates pinning solute drag Ti-Nb microalloyed steels

FUZZY KNOWLEDGE ACQUIREMENT IN GATE DESIGN

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Chinese Journal of Mechanical engineering 2000年第1期13卷 70-75,80页

作者： Lou Zhouliang Zhang Yongqing (department of Plastic Forming engineering, {2.) 上海交通大学上海

In order to reduce time and cost in engineering design, such as gate design, integral field knowledge must be obtained efficiently. After studying ID3 and its improved methods, a new algorithm(Fuzzy ID3 ) and its main concepts are presented to overcome some disadvantage in classical ID3 algorithms. In its application of gate design, fuzzy knowledge gotten by the new algorithm is more efficient than the knowledge by other ID3 algorithms, the set of fuzzy knowledge is much smaller than that of knowledge by classical ID3 algorithms. On the other hand, fuzzy knowledge represents field data more naturally to the way of bar thinking and more robust in tolerating imprecise, conflicting and missing information

关键词： Gate design Fuzzy ID3 Knowledge acquirement Expert system

MORPHOLOGY OF MELT SPINNING SUPERSATURATED B2.NiAl

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 89-93页

作者： SUN Baode CHE Xiaozhou LIN Dongliang ZHOU Yaohe(department of Materials engineering,{2.,shanghai 2.030,China)(department of Materials Science,{2.,shanghai 2.0030,China) shanghai jiaotong Univ Shanghai China

The morphology and structure of melt spinning Ni-33.6at% Al doped with B and RE were *** results show that the alloy consists of L10 martensitic grains and L12.Ni3Al at the grain boundaries when it contains no B and *** addition of 0.11-0.31wt% B can suppress the martensitic transformation and Ni3Al separation at the boundaries,and a supersaturated B2.single phase NiAl is *** addition of 0.05wt% RE can eliminate Ni3Al precipitated at the boundaries and get complete martensite,but 0.2.0.8wt% RE addition can suppress the martensitic transformation, and supersaturated B2.single phase NiAl is *** formation mechanism of supersaturated B2.single phase NiAl has been analyzed.

关键词： NiAl supersaturate morphologl melt spinning

A NONLINEAR THERMOCAPILLARY MIGRATION OF DROPLETS DUE TO DEPENDENCE OF PHYSICAL PROPERTIES ON TEMPERATURE

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Journal of Hydrodynamics 2006年第4期18卷 469-474页

作者： SUN Ren department of engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

A slow thermocapillary migration of a droplet at vanishingly small Reynolds and Marangoni numbers was theoretically investigated. A force on the droplet released in another liquid subjected to arbitrary configuration of the gravitational field and an imposed thermal gradient for the case of constant liquid properties was derived using the general solutions given by Lamb. A solution to the migration was thereby obtained, which corresponds to the well-known YGB result as t →∞. In the case of variable physical properties with temperature, a nonlinear migration of the droplet was described by the dynamical equation of motion, and the numerical results were compared with available experimental data. The comparison exhibits a reasonable agreement between the theoretical prediction and the experimental results, which shows the dependence of physical properties on temperature is a primary cause of the continuous velocity variation in the thermocapillary droplet migration.

关键词： thermocapillary migration droplet/bubble dynamics interfacial tension thermal gradient

NUMERICAL SIMULATION OF MORPHOLOGY OF POLYMER CHAIN COILS IN COMPLEX FLOWS

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Chinese Journal of Polymer Science 2005年第5期23卷 453-462页

作者： Hong Zheng Wei Yu Chi-xing Zhou department of Polymer Materials Science & engineering,{2.,shanghai 2.02.0,China shanghai Jiao Tong Univ Dept Polymer Mat Sci & Engn Shanghai 200240 Peoples R China

A new coupled finite element formulation is proposed to calculate a conformation tensor model in two complex flows： a planar contraction flow and a planar flow around a symmetrically placed cylinder. The components of conformation tensor are first computed together with the velocity and pressure to describe the change of morphology of polymer chain coils in flow fields. Macroscopic quantities of viscoelastic flow are then calculated based on the conformation tensor. Comparisons between the numerical simulations and experiments for stress patterns and velocity profiles are carried out to prove the validity of the method.

关键词： Viscoelastic flow Morphology Complex flows Conformation tensor model Finite element method (FEM).