Adaptive partition and hybrid method in fractal video compression

Fractal image compression is a relatively recent image compression method, which is simple to use and often leads to a high compression ratio. These advantages make it suitable for the situation of a single encoding and many decoding, as required in video on demand, archive compression, etc. There are two fundamental fractal compression methods, namely, the cube-based and the frame-based methods, being commonly studied. However, there are advantages and disadvantages in both methods. This paper gives an extension of the fundamental compression methods based on the concept of adaptive partition. Experimental results show that the algorithms based on adaptive partition may obtain a much higher compression ratio compared to algorithms based on fixed partition while maintaining the quality of decompressed images.     

Short gamma-ray bursts near and far

Progress in understanding the nature of short gamma-ray bursts (GRBs) has been rapid since the discovery of the first afterglows in mid-2005. The emerging picture appears to be of short GRBs, which originate at moderate redshift (a few tenths) and appear in galaxies of all ages. This discovery has been used to argue for their origin in compact binary mergers. However, this population does not describe all short bursts. Here, I will present results of observations of several short GRBs, which challenge the conclusions drawn from the early observations. The observations show that some short GRBs originate in the very low redshift Universe (below 100Mpc), while some may also lie at redshifts comparable with the long GRBs (i.e. z>2). I will discuss the properties of these bursts and the implications they have for the progenitors of short GRBs.     

Ethical Issues in Software Engineering Research: A Survey of Current Practice

In this paper we explore how the software engineering research community is currently dealing with the ethical issues that some empirical research presents. We discuss how the immaturity of the software engineering discipline is reflected in an approach to ethical issues that compares unfavourably with other more mature disciplines.We show that an analysis of recent published work measures an increase in empirical software engineering research currently being undertaken. We also discuss our survey of UK University Department Heads which explores how the software engineering research community is dealing with the ethical issues related to empirical work. Overall we found that whilst some UK Universities have taken ethical issues very seriously, others have not considered the issues.     

Behaviours of near two-dimensional ventilation configurations

Performances of eight configurations of a ventilated room are predicted. The flows exhibit increasingly three-dimensional tendencies as the proportion of wall occupied by the supply and extract vents is reduced. For all of the cases studied, short-circuiting of the air-flow is predicted. Using the concept of the air-exchange effectiveness alone, as a comparative indicator of ventilation performance, is questionable.     

Assessing the UK policies for broadband adoption

Broadband technology has been introduced to the business community and the public as a rapid way of exploiting the Internet. The benefits of its use (fast reliable connections, and always on) have been widely realised and broadband diffusion is one of the items at the top of the agenda for technology related polices of governments worldwide. In this paper an examination of the impact of the UK government’s polices upon broadband adoption is undertaken. Based on institutional theory a consideration of the manipulation of supply push and demand pull forces in the diffusion of broadband is offered. Using primary and secondary data sources, an analysis of the specific institutional actions related to IT diffusion as pursued by the UK government in the case of broadband is provided. Bringing the time dimension into consideration it is revealed that the UK government has shifted its attention from supply push-only strategies to more interventional ones where the demand pull forces are also mobilised. It is believed that this research will assist in the extraction of the “success factors” in government intervention that support the diffusion of technology with a view to render favourable results if applied to other national settings.