A new algorithm of tracking time-varying channels in impulsive noise environment using a robust Kalman filter

2005 International Symposium on Intelligent Signal Processing and Communication Systems (ISPACS 2005), Hong Kong, 13-16 December 2005This paper proposes a new algorithm for tracking time-varying channels in impulsive noise environment using a robust Kalman filter. It employs a simple dynamical model of the channel, where the changes in the impulse response coefficients are due entirely to the innovations of the Kalman filter. This reduces the arithmetic complexity, while offering reasonable good performance. The robust Kalman filter is used to restrain the adverse effect of impulsive noise and provide estimates of the covariance matrices of the state and measurement noises. The noisy channel estimates from the Kalman filter can be used to estimate the parameters of the channel coefficients when they are assumed to follow an AR model. Finally, the two processes can be coupled together to further improve the performance. Simulation results show that the new algorithm gives more stable performance than the conventional methods under impulsive noise environment. © 2005 IEEE.published_or_final_versio

Four-dimensional visualization of construction scheduling and site utilization

Author name used in this publication: K. W. Chau2003-2004 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

4D dynamic construction management and visualization software : 1. Development

Author name used in this publication: K. W. Chau2004-2005 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Generation of solitary waves by transcritical flow over a step

It is well-known that transcritical flow over a localized obstacle generates upstream and downstream nonlinear wavetrains. The flow has been successfully modelled in the framework of the forced Korteweg - de Vries equation, where numerical and asymptotic analytical solutions have shown that the upstream and downstream nonlinear wavetrains have the structure of unsteady undular bores, connected by a locally steady solution over the obstacle, which is elevated on the upstream side and depressed on the downstream side. Inthispaper we consider the analogous transcritical flow over a step, primarily in the context of water waves. We use numerical and asymptotic analytical solutions of the forced Korteweg - de Vries equation, together with numerical solutions of the full Eulerequations, to demonstrate that a positive step generates only an upstream-propagating undular bore, and a negative step generates only a downstream-propagating undular bore. © 2007 Cambridge University Press.published_or_final_versio

Validation of the Chinese version of the Reynolds' suicidal ideation questionnaire: psychometric properties and its short version

BACKGROUND: This study aims to validate the Chinese version of the Reynolds' Suicidal Ideation Questionnaire (SIQ) in a Chinese society and explore a convenient short version. METHODS: A sample of 711 cases was derived from two territory-wide surveys of Hong Kong adolescents aged between 15 and 19 years old. RESULTS: The SIQ and the Suicidal Ideation Questionnaire-Junior (SIQ-JR) demonstrated good reliability and concurrent validity among Hong Kong adolescents. However, the factor structure for both SIQ and SIQ-JR appeared to be unclear. A four-item short form of the SIQ-JR, namely, SIQ-JR-4, was proposed. CONCLUSION: The SIQ-JR-4 is an ideal substitute of the SIQ/SIQ-JR for future quick assessment of suicidal ideation in Chinese young adolescents

A new robust kalman filter algorithm under outliers and system uncertainties

This paper proposes a new robust Kalman filter algorithm under outliers and system uncertainties. The robust Kalman filter of Durovic and Kovacevic is extended to include unknown-but-bounded parameter uncertainties in the state or observation matrix. We first formulate the robust state estimation problem as an M-estimation problem, which leads to an unconstrained nonlinear optimization problem. This is then linearized and solved iteratively as a series of linear least-squares problem. These least-squares problems, subject to the bounded system uncertainties using the robust least squares method proposed by A. Ben-Tal and A. Nemirovski. Simulation results show that the new algorithm leads to a better performance than the conventional algorithms under outliers as well as system uncertainties. © 2005 IEEE.published_or_final_versio

On the multiple-access capacity of multitone-CDMA communications

This letter derives a bit-error-probability expression for an asynchronous multitone-code-division multiple access (CDMA) system and shows that the multiple-access (MA) capacity of this system is identical to that of a conventional (single-carrier) direct-sequence spread-spectrum system under conditions of equal bandwidth and equal bit rate. It is also shown that using more subcarriers to increase the processing gain does not increase the MA capacity.published_or_final_versio

4D dynamic management for construction planning and resource utilization

Author name used in this publication: K. W. Chau2003-2004 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Application of data warehouse and Decision Support System in construction management

Author name used in this publication: K. W. Chau2002-2003 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe