28434248
Optimized Rate Allocation for Unbalanced Multiple Description Video Coding Over Unreliable Packet Network
8253940
A pinhole camera modeling of motion vector field for tennis video analysis
The motion vector field (MVF) represents motion characteristics in video sequences, and has been widely used and been proved to be effective in sports video analysis. However, in tennis video analysis, MVF-based methods are seldom utilized for the reasons that: (i) the players' true motion is not accurately represented by the extracted motion vector, due to the deformation caused by the diagonal shooting of the camera; and (ii) the motion vector's magnitude is not prominent enough and is prone to be disturbed by noises. In this paper, a pinhole camera modeling of the motion vector field is proposed to revise the deformed motion vector. In this modeling, a foreground object mask is adopted and global motion compensation is incorporated as the pre-processing steps. Evaluation of the proposed modeling using four hours of tennis videos shows very encouraging results.
16772027
CCL-SVC: Optimizing user experience of broadcasting video on computation capability limited handheld devices
In this paper, we propose a novel scheme using computing complexity layered scalable video coding (CCLSVC) to optimize the user experience of broadcasting video in the computing capability limited handheld terminals. To address the heterogeneity of computing capability among different handheld devices, we employ hierarchal B reference structure of SVC to divide the frames into multiple computing complexity layers (CC Layers) in server side. The handheld clients simply choose to decode the frames in their corresponding layers in terms of their computation capability to maximize the video PSNR. We have proved that the optimal CC Layers division problem is a precedence constrained scheduling problem, which is an NP-complete problem. And we further propose our fast greedy method to approximately get optimized broadcasting video playback PSNR. The simulation shows that our method is superior to temporal SVC and random frame discarding method.
5295208
Bit rate reduction of H.264/AVC video coding for mobile applications
The increasing use of mobile applications requires higher compression efficiency for video coding. However, in mobile applications, the capability of the processor is limited and the channel is unreliable. Since the emerging H.264/AVC video coding standard provides superior compression performance compared to all the existing video coding standards, many research efforts concentrate on the compression efficiency of intra-frame coding in H.264/AVC. In this paper, we propose a novel algorithm to reduce the bit rate compressed by H.264/AVC intra-frame coding. We focus on the method to code the intra-frame prediction modes. Our proposed method significantly reduces the bits used to code the modes and do not change the syntax of the bit stream. Experimental results demonstrate it is effective and efficient
28617398
An Unbalanced Multiple Description Coding Scheme for Video Transmission Over Wireless Ad Hoc Networks
5815107
SIKAS: A Scalable Distributed Key Management Scheme for Dynamic Collaborative Groups
The increasing popularity of distributed and collaborative applications prompts the need for secure communication in collaborative groups. Some distributed collaborative key management protocols have been proposed to provide group communication privacy and data confidentiality for collaborative groups. However, most of them rekey on each member change, and the costs of group rekeying can be quite substantial for large groups with frequent membership changes. In this paper, we propose a scalable distributed key management scheme using a distributed one-way function tree named SIKAS which can significantly reduce the computation and communication costs of maintaining the group key based upon period-based group rekeying. A comparison with previous work has shown that SIKAS provides scalability and rekeying efficiency while preserving both distributed and collaborative properties
16922329
A New Transmit Scheme Combining Beamforming with Space-Time Block Coding
In this paper, a new transmit scheme combining beamforming (BF) with space-time block coding (STBC) is proposed for correlated fading channels. Based on maximizing the output mean signal-to-noise ratio (SNR) at the receiver, the transmitter BF weight vectors are first derived. Then, utilizing the minimal bit error rate (BER) upper bound as the design criterion, a simple power allocation algorithm is developed. Next, the BER performance of the system with the proposed transmit scheme is analyzed by considering an M-QAM constellation. Finally, computer simulation results are given to verify the effectiveness of the proposed scheme.
34492999
Adaptive Neural Network Path Tracking of Unmanned Ground Vehicle
Unmanned ground vehicles (UGVs) play an increasingly important role in future space exploration and battlefield. This work is concerned with the automatic path tracking control of UGVs. By using the structure properties of the system, neuro-adaptive control algorithms are developed for high precision tracking without involving complex design procedures – the proposed control scheme only demands partial information of the system, no detail description of the system model is needed. Furthermore, uncertain effects such as external disturbance and uncertain parameters can easily be handled. In addition, all the internal signals are uniformly bounded and the control torque is smooth anywhere.
14435465
A hardware/software partitioning algorithm based on artificial immune principles
Hardware/software codesign is the main approach to designing the embedded systems. One of the primary steps of the hardware/software codesign is the hardware/software partitioning. A good partitioning scheme is a tradeoff of some constraints, such as power, size, performance, and so on. Inspired by both negative selection model and evolutionary mechanism of the biological immune system, an evolutionary negative selection algorithm for hardware/software partitioning, namely ENSA-HSP, is proposed in this paper. This ENSA-HSP algorithm is proved to be convergent, and its ability to escape from the local optimum is also analyzed. The experimental results demonstrate that ENSA-HSP is more efficient than traditional evolutionary algorithm.
37887576
Design and Application of GIS Software Platform Integrating with DSS Oriented to E-Government
Both Geographic Information System (GIS) and decision support system (DSS) are playing an important part in government affairs management or electronic government (E-government). But GIS and DSS are usually independently working the interactive relation between them is unsubstantial, so that application of E-government to GIS is inconvenient and inefficient. This paper puts forward a new idea for designing software platform based on integrative GIS and DSS according to target of E-government construction in China, introduces the function integration target, method and technical way in different levels of this platform. This paper has found a new way of GIS development oriented to E-government, and described successful application in a series of G-government project, such as General National Situation Information System, Flood and Drought Prevention Information Service System, West Development Information Service System and so on.
6883051
Studies on lateral rolling locomotion of a snake robot
A reconfigurable modular snake robot has been developed, which can not only move on a plane but aIso achieve some f-dimensional motions while reconfigured. Control equations of 3-dimensional locomotion were established by the composition of two bending motions in mutual orthogonal plane. Three types of lateral rolling locomotion, flapping, linear rolling and curved rolling, were achieved by controlling the amplitudes and the number of two waves in the two bending motions. Using the three types of locomotion the snake robot can realize net lateral translation, alternation of its contact base and rolling over some obstacles. The lateral rolling locomotion obtains its driving force through the interaction with the environment. The rolling shape and its direction depend on the transferring direction and phase difference of the two waves respectively.