426930
An admission control scheme for end-to-end statistical QoS provision in IP networks
This paper presents a distributed and scalable admission control scheme to provide end-to-end statistical QoS guarantees in IP network. The basic idea of the scheme is that the ingress routers make admission control decisions according to the network status information obtained by sending probing packets along the selected routing path. Each router passively monitors the arriving traffic and marks the probing packets with its network status. The performance of the presented scheme is evaluated with a variety of traffic models, QoS metrics and network topologies. The simulation results show that the proposed scheme can accurately control the admissible region and effectively improve the utilization of network resource.
46299738
Web Clustering and Association Rule Discovery for Web Broadcast
When we broadcast web pages package through broadband broadcast network, what we will broadcast and how we broadcast are two problems. First, we formalize these problems as a clustering problem. Second, we use the association rule to give a better result. In this paper we provide a new web mining method WebClustering to resolve these problems. This method combines the clustering idea and association rule discovery idea. The mining object is the web pages of Cache and Log in WWW Proxy server. By this method we can find a valuable Web broadcast set and create some index HTML pages to direct the users to navigate.
18884970
Performance Characterisation of Face Recognition Algorithms and Their Sensitivity to Severe Illumination Changes
This paper details the results of a face verification competition [2] held in conjunction with the Second International Conference on Biometric Authentication. The contest was held on the publically available XM2VTS database [4] according to a defined protocol [15]. The aim of the competition was to assess the advances made in face recognition since 2003 and to measure the sensitivity of the tested algorithms to severe changes in illumination conditions. In total, more than 10 algorithms submitted by three groups were compared. The results show that the relative performance of some algorithms is dependent on training conditions (data, protocol) as well as environmental changes.
481878
Reducing Spatial Resolution for MPEG-2 to H.264/AVC Transcoding
Transcoding is an important technique for reducing the bit rate or spatial resolution to meet the constrained transmission bandwidths and terminal capabilities. In this paper, we propose a spatial downscaling transcoding method to convert an MPEG-2 bitstream into an H.264/AVC bitstream. A novel feature of the proposed method is to focus on the fast mode decision that fully exploits the advantages of variable block-size motion compensation feature in H.264/AVC. In the transcoder, types and motion vectors of pre-encoded macroblocks are considered together to decide the new encoding block type. While maintaining a reasonable image quality, the proposed method significantly reduces the computational complexity and facilitates the video servers to provide multimedia service in real time for heterogeneous clients. Experimental results show that our method is very effective.
15693719
Context-based Arithmetic Coding Reexamined for DCT Video Compression
This paper presents a new context modeling technique for arithmetic coding of DCT coefficients in video compression. A key feature of the new technique is the inclusion of all previously coded coefficient magnitudes in a DCT block in context modeling. This enables adaptive arithmetic coding to exploit the redundancy of the high-order Markov process in the DCT domain with a few conditioning states. In addition, a context weighting technique is used to further improve the coding efficiency. The complexity of the new arithmetic coding scheme is slightly lower than that of context-based adaptive binary arithmetic coding (CABAC) of H.264. Moreover, the scheme is made compatible to the AVS baseline profile. It achieves on average 13% improvement in compression ratio over context-based two dimension variable length coding (C2DVLC) designed for the DCT domain, and a similar coding efficiency as the CABAC technique in H.264.
58983783
Review the strength of Gabor features for face recognition from the angle of its robustness to mis-alignment
Gabor feature has been widely recognized as better representation for face recognition in terms of rank-1 recognition rate. In this paper, we review the strength of Gabor feature for face recognition from the new angle of its robustness to mis-alignment using a novel quantificational evaluation method combining both the alignment precision and the recognition accuracy. Our experiments show that, compared with the gray-level intensity, Gabor feature is much more robust to image variation caused by the imprecision of facial feature localization, which further support the feasibility of Gabor representation.
8471073
Spectrum Sensing for DMB-T Systems Using PN Frame Headers
Spectrum sensing for the China digital television terrestrial broadcasting system is considered in this paper. The spectrum sensing algorithms utilize PN sequences embedded in the frame headers to perform spectrum sensing. A theoretical lower bound on the misdetection probability for each spectrum sensor presented in this paper is derived. The performances of the proposed spectrum sensing algorithms are demonstrated by computer simulation for the multipath Rayleigh fading and steady state multipath Rayleigh fading channels. Simulation results show that the misdetection probability evaluated by computer simulations is close to the lower bound on the misdetection probability for a steady state multipath Rayleigh channel. When the probability of false alarm is 0.01 and a 50 ms of sensing time is used, a misdetection probability equal to 0.1 is achieved when the signal to noise power ratio is -16 dB, -18.8 dB, and -18 dB for modes 1, 2, and 3 in the multipath Rayleigh fading channel, respectively.
39625644
An AVS Based IPTV System Network Trial
This paper unveils the solution of an AVS1-P2 based IPTV (AVSIPTV) system network trial, which is architected with the common three levels such as national, provincial and urban level, and each system function of each level is described. In order to verify the solution, the AVS-IPTV testing and verification environment has been setup in the China Netcom Group labs, which promoted STB (Set-top box) to support AVS. An AVS-IPTV system network commercial trial has been successfully deployed to test and verify the performance of the AVS-IPTV system function, EPG (Electronic Program Guide), AVS streaming service, and the quality of experience. The trial makes AVS standard and AVS-IPTV system commercially applicable in the real world.
36578035
Mobile robot sonar interpretation algorithm for distinguishing trees from poles
Abstract We describe an algorithm to automatically distinguish trees from round metal poles with a sonar system packaged on a mobile robot. A polynomial interpolation of the square root of the backscattered signal energy versus scan angle is first plotted. Asymmetry and fitting error are then extracted for each sweep across the object, giving a single point in an abstract phase space. Round metal poles are nearer to the origin than are trees, which scatter the sonar more irregularly due to lobulations and/or surface roughness. Results are shown for 20 trees and 10 metal poles scanned on our campus.
5747221
Application Research of Design Patterns in Virtual Trade Platform
Shanxi Coal Transportation and Marketing Group Limited has abundant coal and infrastructure network resources, maturity the highway system of coal transportation. The construction of virtual trade platform can share resources, accelerate the circulation speed of resources, reduce business costs, and improve business efficiency. The paper applies design pattern to virtual trade platform. The system has the advantage of strong scalability and maintainability, easy to develop and support multiple types of user interface.
39810254
NCPN: A Simulation Tool for Coloured Petri Nets