Automatic 3D Shape Co-Segmentation Using Spectral Graph Method

Co-analyzing a set of 3D shapes is a challenging task considering a large geometrical variability of the shapes. To address this challenge, this paper proposes a new automatic 3D shape co-segmentation algorithm by using spectral graph method.Our method firstly represents input shapes as a set of weighted graphs and extracts multiple geometric features to measure the similarities of faces in each individual shape.Secondly all graphs are embedded into the spectral domain to find meaningful correspondences across the set.After that we build a joint weighted matrix for the graph set and then apply normalized cut criterion to find optimal co-segmentation of the input shapes.Finally we evaluate our approach on different categories of 3D shapes, and the experimental results demonstrate that our method can accurately co-segment a wide variety of shapes, which may have different poses and significant topology changes.     

DPGL： The Direct3D9-based Parallel Graphics Library for Multi-display Environment

The emergence of high performance 3D graphics cards has opened the way to PC clusters for high performance multi- display environment.In order to exploit the rendering ability of PC clusters,we should design appropriate parallel rendering algorithms and parallel graphics library interfaces.Due to the rapid development of Direct3D,we bring forward DPGL,the Direct3D9-based parallel graphics library in D3DPR parallel rendering system,which implements Direct3D9 interfaces to support existing Direct3D9 application parallelization with no modification.Based on the parallelism analysis of Direct3D9 rendering pipeline,we briefly introduce D3DPR parallel rendering system.DPGL is the fundamental component of D3DPR.After presenting DPGL three layers architecture, we discuss the rendering resource interception and management.Finally,we describe the design and implementation of DPGL in detail, including rendering command interception layer,rendering command interpretation layer and rendering resource parallelization layer.     

A Rapid Generation Method of Character Doll with Rotatable Limbs Oriented to 3D Printer

Currently, 3D printing of the character dolls is a very practical application for the average person. But the model of doll which can be obtained is static so the posture of the doll is single. On the other hand, the modification of the model is very difficult to non-professions. This paper proposes an rapid generation method of character doll with rotatable limbs, which is through adding the sphere joint to the doll＇s model automatically. After the model is segmented by drawing a line interactively, the sphere joint is created based on the segmentation boundary through entity modeling method. Lastly the two models of the doll and the joint are composited and printed. Some doll＇s model are tested on the FDM（Fused Deposition Modeling） 3D printer using this process. The results are more interesting and the efficiency has been greatly improved compared with modifying the model manually.     

Exploiting AML algorithm for multiple acoustic source 2D and 3D DOA estimations

The approximate maximum likelihood (AML) algorithm shows promises for joint estimations of acoustic source spectrum and direction-of-arrival (DOA). For the multisource case, the AML algorithm remains feasible as one considers an alternating projection procedure based on sequential iterative search on single source parameters. In order to perform multisource beamforming operations, earlier, we used a two-dimensional (2D) sensor array with 2D AML to obtain the DOA estimations for sources in the far field of t...     

System identification with binary-valued observations under both denial-of-service attacks and data tampering attacks:defense scheme and its optimality

In this paper,we investigate the defense problem against the joint attacks of denial-of-service attacks and data tampering attacks in the framework of system identification with binary-valued observations.By estimating the key parameters of the joint attack and compensating them in the identification algorithm,a compensation-oriented defense scheme is proposed.Then the identification algorithm of system parameter is designed and is further proved to be consistent.The asymptotic normality of the algorithm is obtained,and on this basis,we propose the optimal defense scheme.Furthermore,the implementation of the optimal defense scheme is discussed.Finally,a simulation example is presented to verify the effectiveness of the main results.     

System identification with binary-valued observations under both denial-of-service attacks and data tampering attacks: defense scheme and its optimality

In this paper, we investigate the defense problem against the joint attacks of denial-of-service attacks and data tampering attacks in the framework of system identification with binary-valued observations. By estimating the key parameters of the joint attack and compensating them in the identification algorithm, a compensation-oriented defense scheme is proposed. Then the identification algorithm of system parameter is designed and is further proved to be consistent. The asymptotic normality of the algorithm is obtained, and on this basis, we propose the optimal defense scheme. Furthermore, the implementation of the optimal defense scheme is discussed. Finally, a simulation example is presented to verify the effectiveness of the main results.     

多比例尺下的三维GIS细节层次可视化技术

In this paper ,by investigating leve!yof detail in 3D GIS,we integrate generalization techniqueswith 3D visualization techniques on the basis of object oriented database. In order to improve the perfor-mance of database access ,we investigate the access structure based on modified reactive tree and analyzethe detailed method of representing level of detail. This approach visualizes 3I) object with object-orient-ed database and integrates generalization with 3I) visualization techniques ,3D G-IS is expected to achievebetter performance of query and photo-realistic visualization at multi-scale。     

Rectification of 3D data obtained from moving range sensor by using extended projective multiple view geometry

To measure the 3D shape of large objects, scanning by a moving range sensor is one of the most efficient methods. However, if we use moving range sensors, the obtained data have some distortions due to the movement of the sensor during the scanning process. In this paper, we propose a method for recovering correct 3D range data from a moving range sensor by using the multiple view geometry under projective projections in space-time. We assume that range sensor radiates laser beams in a raster scan order, and they are observed from two cameras. We first show that we can deal with range data as 2D images, and show that the extended multiple view geometry can be used for representing the relationship between the 2D image of range data and the 2D image of cameras. We next show that the extended multiple view geometry can be used for rectifying 3D data obtained by the moving range sensor. The method is implemented and tested in synthetic images and range data. The stability of the recovered 3D shape is also evaluated.     

基于特定角色上下文的多智能体Q学习

One of the main problems in cooperative multiagent learning is that the joint action space grows exponentially with the number of agents. In this paper, we investigate a sparse representation of the coordination dependencies between agents to employ roles and context-specific coordination graphs to reduce the joint action space. In our framework, the global joint Q-function is decomposed into a number of local Q-functions. Each local Q-function is shared among a small group of agents and is composed of a set of value rules. We propose a novel multiagent Q-learning algorithm which learns the weights in each value rule automatically. We give empirical evidence to show that our learning algorithm converges to the same optimal policy with a significantly faster speed than traditional multiagent learning techniques.     

On controllability and stabilizability of probabilistic Boolean control networks

The controllability of probabilistic Boolean control networks(PBCNs)is first considered.Using the input-state incidence matrices of all models,we propose a reachability matrix to characterize the joint reachability.Then we prove that the joint reachability and the controllability of PBCNs are equivalent,which leads to a necessary and sufcient condition of the controllability.Then,the result of controllability is used to investigate the stability of probabilistic Boolean networks(PBNs)and the stabilization of PBCNs.A necessary and sufcient condition for the stability of PBNs is obtained first.By introducing the control-fixed point of Boolean control networks(BCNs),the stability condition has finally been developed into a necessary and sufcient condition of the stabilization of PBCNs.Both necessary and sufcient conditions for controllability and stabilizability are based on reachability matrix,which are easily computable.Hence the two necessary and sufcient conditions are straightforward verifiable.Numerical examples are provided from case to case to demonstrate the corresponding theoretical results.     

Design of tracking observers for locally jointly observable systems

This paper considers distributed state estimation of continuous-time linear system monitored by a network of multiple sensors. Each sensor can only access locally partial measurement output of the system and effectively communicates with its neighbors to cooperatively achieve the asymptotic estimation of the target full system state. For a constructive design, we shall incorporate the concept of system immersions and propose a class of distributed tracking observers for the problem under a reasonable condition of the locally joint observability. Moreover, as a direct application of the proposed observer design, we further present an interesting leader-following consensus design for multi-agent system.     

The Layout and Simulation of Logarithmic Spiral Double Curved Arch Dam Transverse Joints

Because of its good condition with mechanics,logarithmic spiral double curve arch bam has been widely used in the practical engineering.The introduction of a new method in how to divide transverse joint in arch dam will be given and the further research of its calculation has been done.The C++ is used in electronic procedure and the 3D simulation has been finished with AutoCAD,which will provide the object model for computer simulation of the arch dam and the division of finite element mesh.Meanwhile,this method in dividing the transverse joint in arch dam also can be taken as the calculated basis for the design and calculation of arch dam,construction lofting and the calculation of the work amount.     

Performance driven expression mapping based on segmented examples

We present a method that combines performance-driven method with segmented 3D blendshape models to animate a face.First we prepare key sample examples and corresponding key target examples.Next we segment the whole face into two regions,for each region we reduce dimensionality of source examples using PAC into abstract space which is defined by truncated PCA eigenvectors.Then for each example we fix the cardinal base function,which can determine the weight of the target example.Finally,in the animation stage we compute the weight of each example for each frame and add the weighted displacement vectors of each region on the general face model.     

A Survey on Partial Retrieval of 3D Shapes

Content-based shape retrieval techniques can facilitate 3D model resource reuse, 3D model modeling, object recognition, and 3D content classification.Recently more and more researchers have attempted to solve the problems of partial retrieval in the domain of computer graphics, vision, CAD, and multimedia.Unfortunately, in the literature, there is little comprehensive discussion on the state-of-the-art methods of partial shape retrieval.In this article we focus on reviewing the partial shape retrieval methods over the last decade, and help novices to grasp latest developments in this field.We first give the definition of partial retrieval and discuss its desirable capabilities.Secondly, we classify the existing methods on partial shape retrieval into three classes by several criteria, describe the main ideas and techniques for each class, and detailedly compare their advantages and limits.We also present several relevant 3D datasets and corresponding evaluation metrics, which are necessary for evaluating partial retrieval performance.Finally, we discuss possible research directions to address partial shape retrieval.     

Joint subcarrier,code, and power allocation for parallel multi-radio access in heterogeneous wireless networks

In the heterogeneous wireless networks, it has been proved that the joint spectrum and power allocation can achieve network diversity gains for parallel multi-radio access in theory. This article aims to develop an effective and practical algorithm of joint subearrier, code, and power allocation for parallel multi- radio access of the downlink in heterogeneous wireless networks （e.g., CDMA and OFDMA）. Firstly, we propose a unified framework to formulate the subcarrier, code, and power allocation as an optimization problem. Secondly, we propose a resource element （subcarrier and code） scheme based on the threshold type. Simulation results show that the proposed scheme outperforms the existing algorithm for considered wireless scenarios.     

Boundary-representable partition of unity for image magnification

This paper proposes a simple yet effective algorithm to magnify 2D/3D images with preserving discontinuities of intensity. Our algorithm is based on the partition of unity （PU） approximation, which offers many advantages such as smooth representation, noise-robustness, and precise representation. Unfortunately, PU encounters difficulties when scaling images and maintaining boundaries within images owing to the nature of its approximation. To overcome this problem, we propose an approximation that preserves discontinuities. This is realized by dividing the local spherical support of PU into two parts along a locally detected discontinuity and by individually approximating intensities on each side of the discontinuity. This algorithm is suitable for magnifying a variety of images, including scanned documents, pictures, and CT-scanned images. To demonstrate the effectiveness of the proposed method, we show some experimental results for 2D/3D images.     

Joint optimal sensing time and power allocation for multi-channel cognitive radio networks considering sensing-channel selection

In this paper,we consider a multi-channel cognitive radio network(CRN)where each secondary user(SU)can only choose to sense a subset of channels.We formulate a joint optimization problem of sensingchannel selection,sensing time and power allocation under the constraints of average transmit power budget and average interference power budget,which maximizes the CRN’s total throughput.We propose a greedy algorithm to solve the joint optimization problem,which has much less computational complexity.Moreover,it is shown that the search space of the greedy algorithm can be further pruned.Finally,numerical results demonstrate that the greedy algorithm has comparable performance to the exhaustive search algorithm.     

Infrared Image Target Segmentation Processing Based On Space-Time Combination

This paper puts forward a scheme of target time-domain segmentation on the basis of analyzing time-domain characteristics of sequence images and targets＇ gray level characteristics in time-domain. On the suggestion of multi-variable joint distribution probability, we discover a new target segmentation method based on space-time joint on the help of the method that makes use of space-time fusing to enhance targets. And the new method has considered both targets＇ gray level distributing characteristics in single-frame image and their gray levels and moving speed continuities in bordered some frame images. Joining both of the segmented images and the realization of time-domain processing and single-frame processing parallel can greatly cut calculating time and apparently improve the effect of image segmentation. The result of experiment indicates that it is feasible to fuse two-frame image of single-frame target enhancing and time-domain target enhancing first and segment them secondly, and it can also greatly improve the precision and universality of segmentation.     

Evaluation for Small Visual Difference Between Conforming Meshes on Strain Field

This paper gives a method of quantifying small visual differences between 3D mesh models with conforming topology, based on the theory of strain fields. Strain field is a geometric quantity in elasticity which is used to describe the deformation of elastomer. In this paper we consider the 3D models as objects with elasticity. The further demonstrations are provided: the first is intended to give the reader a visual impression of how our measure works in practice; and the second is to give readers a visua...