ion of agent percepts. The rest of the paper is organised as follows. Section 2 contains an introduction to Second Life and Section 3 contains our formalism for virtual environments. Section 4 discusses the challenges and problems in accurately extracting spatio-temporal data from Second Life environments using existing mechanisms. Section 5 presents the new mechanisms that we developed to accu...

The emergence of video has presented new challenges to the problem of face recognition. Most of the existing methods are focused towards the use of either representative exemplars or image sets to summarize videos. There is little work as to how they can be combined effectively to harness their individual strengths. In this paper, we investigate a new dual-feature approach to face recognition i...

There is growing recognition of the importance of the role of architecture in determining the quality of a software system. While a good architecture cannot guarantee attainment of quality goals, a poor architecture can prevent their achievement. It is particularly important to evaluate the performance of a distributed system architecture. Errors made early can cause excessive overhead for comm...

In a wide-area network with high-speed links, congestion may lead to poor utilization and the degradation of the service provided to the users. This paper presents a Cooperative Congestion Management Scheme in which the intermediate nodes in the vicinity of a congested link share their resources to offload this link before packets are discarded. The scheme uses a progression of proactive contro...

Since the early 1990’s, a variety of studies has shown that network traffic, both for localand wide-area networks, has self-similar properties. This led to new approaches in network traffic modelling because most traditional traffic approaches result in the underestimation of performance measures of interest. Instead of developing completely new traffic models, a number of researchers have prop...

The determinants of the dimensions that shape a formal system of performance appraisal are studied in relation to a sample of Spanish manufacturing establishments. In particular, the factors that influence the measures used to evaluate performance, the person who carries out such appraisal and its frequency are analysed. Our results show that the characteristics of the establishment exert a sig...

Aiming to advance the coning algorithm performance of strapdown inertial navigation systems, a new half-compressed coning correction structure is presented. The half-compressed algorithm structure is analytically proven to be equivalent to the traditional compressed structure under coning environments. The half-compressed algorithm coefficients allow direct configuration from traditional compre...

This work is devoted to the formulation and derivation of the α−κ−μ/gamma distribution which corresponds to a physical fading model. The proposed distribution is composite and is constituted by the α−κ−μ non-linear generalized multipath model and the gamma shadowing model. It also constitute the basis for deriving the α−κ−μ Extreme/gamma model which accounts for non-linear severe multipath and ...

The angular error of indexing table on machine tool is measured using new developed measuring device. The measuring techniques, which have been reviewed in this paper, are currently available in manufacturing engineering to calibrate the angle measurement. The new developed measuring device using 6 points kinematic concept and employing ball and vee grooves is used to calibrate angle errors of ...

The state of many dynamic systems evolves subject to some equality constraints. Under the assumption that the equality constrained dynamic systems are already available, most existing work focuses on developing state estimation algorithms for these systems. However, how to design and analyze such a system is rarely addressed, even though it is critically important for performance evaluation and...