41927172
A Wavelets Network Interpolation Algorithm for OFDM Channel Estimation Systems
For the performance deficiency of the pilot symbol aided channel estimation in orthogonal frequency division multiplexing (OFDM) systems, the wavelets network interpolation channel estimator is proposed. By contrast with conventional methods, wavelets network interpolation channel estimator can guarantee the high transmission rate and lower Bit error rates (BER). Computer simulation results demonstrate that the proposed channel estimation method exhibit an improved performance compared to the conventional linear channel estimation methods and is robust to fading rate, especially in fast fading channels.
4963124
Blind equalization Using ν- support vector regressor for constant modulus signals
The support vector machine has been recently developed for blind equalization of constant modulus signals. In this paper we propose to use a v-support vector regressor (nu-SVR) for blindly equalizing multipath channels because of the high generalization ability of the SVR for short burst sequences. A weighted least square procedure is presented for solving the blind nu-SVR equalizer. The performance of the proposed algorithm is analyzed by means of computer simulations.
36390607
Wavelet-based diffusion approaches for signal denoising
The efficiency of nonlinear diffusion filters is related to diffusivity. In the previous models, diffusivity depended on the derivatives of a signal, and hence it is easily affected by noise. This paper considers the nonlinear wavelet-based diffusion (NWD) methods for signal denoising in which the diffusivity is expressed by the wavelet transforms of received signal at several scales. Due to the multiresolution of wavelet transform, the proposed diffusivity with wavelet transforms efficiently reduces the influence of noise on the estimate of diffusion amount and improves nonlinear diffusion filters. Some numerical experimental results compared with the previous models are shown.
22450367
Networking Business Model In Regional Medical Service- Case of Chikamori Medical Group in Kochi, Japan
Japan's Health Care System has experienced a number of changes over the last half a century. And the most heated aspect of current health policy debate focuses on the potential radical reform of the medical care system. In addition, the regional medical service organizations are in front of a more severe challenge because of the rapidly aging population and decreasing young population. Consequently, hospitals and other NHS organizations in local areas have been required to introduce reforms in their management structure for their survival This paper reports in depth on a case study of a private Japanese hospital, the Chikamori medical group, to introduce a key competence-based management model and differentiation marketing strategy. As one of the regional medical care support hospitals, Chikamori plays an active and important role in the regional medical care network. The case implies the effective business model based on positioning in the network architecture, which is significant not only for medical service field but also for other regional industries. The mutual correlations among financial strategy, human resource design, managing policy and collaboration manner with regional doctors are discussed in the paper.
17447352
Using Simulation to Characterize Topology of Peer to Peer Botnets
Future network intruders are constantly changing, improving and extending the capabilities of their botnets. Peer to peer bots are now under widespread development and are quickly evolving into a much tougher species to kill. However, partly due to the lack of understanding of the structural potential of command and control mechanism a botnets can have, countering peer to peer botnets has been ineffective. In this paper, we explore the characteristic of communication networks created by peer to peer botnets. We propose a simulation approach to characterize the structural properties and robustness of P2P botnets, corresponding to different paradigms of forming botnets. Through calculation and simulation for topology construction procedures, we show that extremely resilient peer to peer botnets can be formed to deliver attack code quickly. Such a theory would help predict botnets containment for a given topology and help develop strategies to improve defense against P2P botnets, because applying those strategies can always translate into some network topology transformation.
27148951
Diffusion filtering in image processing based on wavelet transform
The nonlinear diffusion filtering in image processing bases on the heat diffusion equations. Its key is the control of diffusion amount. In the previous models, the diffusivity depends on the gradients of images. So it is easily affected by noises. This paper first gives a new multiscale computational technique for diffusivity. Then we proposed a class of nonlinear wavelet diffusion (NWD) models that are used to restore images. The NWD model has strong ability to resist noise. But it, like the previous models, requires higher computational effort. Thus, by simplifying the NWD, we establish linear wavelet diffusion (LWD) models that consist of advection and diffusion. Since there exists the advection, the LWD filter is anisotropic, and hence can well preserve edges although the diffusion at edges is isotropic. The advantage is that the LWD model is easy to be analyzed and has lesser computational load. Finally, a variety of numerical experiments compared with the previous model are shown.
6780116
Joint MMSE Vector Precoding Based on GMD Method for MIMO Systems
We propose a geometric mean decomposition (GMD) based vector precoding (VP) for multiple input multiple output (MIMO) systems. Minimum mean square error (MMSE) criterion is used for the joint VP design. The application of GMD method eliminates the imbalance among subchannel gains and obtains a better perturbation vector than the conventional method. We then exploit the extended channel matrix for further performance improvement. Simulation results show the proposed schemes significantly outperform the existing VP schemes.
1165057
An Extensible Three-tier XML Dialogue System Architecture for Multimodal Interaction and Automated Agent Services
8504259
A Low Complexity MPEG Video Decoder with Arbitrary Downscaling Capability
This paper presents some new techniques to implement arbitrary downscaling in decoding MPEG video with very low complexity. The DCT block recomposition method, which was used in resizing static image, is introduced to downscale video in frequency domain with arbitrary factors. New motion compensation based on the block group motion evaluation is proposed to correspond to the downscaled IDCT. Block groups of regular motion and irregular motion are handled respectively to balance the computation cost and picture quality. Analysis indicates the great complexity reduction and experiments show the decoder performance on the MPEG-4 video sequence. These techniques will be beneficial to the video applications on the mobile devices and many other low end embedded systems
1077673
Low Complexity MMSE Vector Precoding Using Lattice Reduction for MIMO Systems
In this paper, a lattice-reduction-aided (LRA) minimum mean square error (MMSE) vector precoding (VP) is proposed for multiple input multiple output (MIMO) systems. Three schemes are provided for the perturbation vector design by Babai's approximation procedures based on lattice reduction method to reduce the complexity. Performance and complexity analysis are provided. Simulation results show that the proposed schemes significantly outperform the conventional MMSE Tomlinson-Harashima precoding (THP) and the zero forcing (ZF) VP. Compared with the MMSE VP via closest-point search, our LRA approach provides a simple alternative with little performance loss.
16207810
Web Services Methods for Communication over IP
In this paper, we study Web services methods and approaches to enable real-time communication services over IP. This approach extends Web services methodologies from service integration to a service-oriented approach for communication. In particular, we describe the generic Web service based application session management, WS-Session, the two-way full duplex Web service interaction framework, and most importantly, the development of Web service initiation protocol (WIP) which is a full featured Web service and SOA based communication framework for multimedia and voice communication over IP. We show that WIP provides a service oriented architecture which can be extended seamlessly from a P2P endpoint to an endpoint with advanced call control and switching capabilities typically requiring the assistance of a dedicated PBX. A prototype of WIP system is fully developed. Architectural design and system implementation of Web service based communication endpoints are studied and applied to realize service-oriented communication over IP. Advances of WIP indicate the beginning of a full Web service and SOA based communication paradigm that can reshape the converged communication over IP.