Rees semigroups of digraphs for classification of data

Recent research has motivated the investigation of the weights of ideals in semiring constructions based on semigroups. The present paper introduces Rees semigroups of directed graphs. This new construction is a common generalization of Rees matrix semigroups and incidence semigroups of digraphs. For each finite subsemigroup S of the Rees semigroup of a digraph and for every zero-divisor-free idempotent semiring F with identity element, our main theorem describes all ideals J in the semigroup semiring F0[S] such that J has the largest possible weight.

Dividend forecasts and dividend payments of initial public offerings-when zero means zero and no comment most likely also means zero

Managers often try to forecast dividends because as Brown et al. (2002)  suggest, dividends have cash flow implications for investors and are important signalling devices. This study analyses the dividend forecasts in the prospectuses of initial public offerings (IPOs) in Australia over the period 1994 to 1999. While many companies forecast dividends, many make no dividend forecast at all and some forecast no (or zero) dividends for the forthcoming year. This paper seeks to determine if no forecast at all should present a different signal to investors than a zero dividend forecast. It is found that those that do not forecast a dividend, by and large, do not pay a dividend. It is also found that those that forecast a zero dividend, true to their forecast, pay no dividend.

Groups, graphs and mutually unbiased bases

A new characteristic free approach to constructing large sets of mutually unbiased bases in Hilbert space is developed. We associate with a seed set of bases a finite subgroup of which defines a strongly regular graph. Large sets of mutually unbiased bases are obtained as the cliques of the graph.

Strategies which aim to positively impact on weight, physical activity, diet and sedentary behaviours in children from zero to five years. A systematic review of the literature

Preventing the development of obesity in children is an international health priority. To assess the effectiveness of interventions designed to prevent obesity, promote healthy eating and/or physical activity and/or to reduce sedentary behaviours in 0–5-year-old children, a systematic review of the literature was performed. Literature searches were limited to articles published between January 1995 and June 2006, printed in English and sampling children aged 0–5-years. Searches excluded literature concerned with breastfeeding, eating disorders, and interventions which were school-based or concerned with obesity treatment. Two reviewers independently extracted data and assessed study strengths and weaknesses. Nine included studies were grouped based on the settings in which they were delivered. Most studies involved multi-approach interventions, were conducted in the USA and varied in study designs and quality. All showed some level of effectiveness on at least one obesity-behaviour in young children. These studies support, at a range of levels, the premise that parents are receptive to and capable of some behavioural changes that may promote healthy weight in their young children. The small quantity of research heralds the need, particularly given the potential for early intervention to have long-lasting impacts on individual and population health, to build in a substantial way upon this evidence base.

Clock synchronization state graphs based on clock precision difference

Consistent and stable global states of clock synchronization are very important in distributed and parallel systems. This paper presents an innovative strategy and method to obtain stable global clock synchronization state graphs in asynchronous Internet environments. Our model will introduce the concept of clock precision difference as a means to evaluate running states of all clocks in this system and make this system  self-adaptive well. Finally, we introduce the concept of clock precision difference into global states analysis of clock synchronization and construct clock synchronization state graphs in order to evaluate distributed clock synchronization states. We also present detailed simulations of the strategy and mathematical analysis used on real Internet environments.

Zero impact: are lawyers' values affected by law school?(Survey)

In 2001 approximately 700 Australian final-year undergraduate law students were surveyed as the first part of a three-year study of Australian lawyers' values. This study is being undertaken in an effort to understand what values are important in determining lawyers' attitudes to difficult behavioural choices confronting them in legal practice. It is hoped that knowledge of the actual values held by lawyers (in the context of critical professional choices) will enable better targeted values awareness education in both pre- and post-admission contexts.

The main quantitative survey employed a number of hypothetical scenarios. These were designed through the use of ethical dilemmas to examine issues of conflicting loyalties within a context of self-interest and lawyers' perceived obligations to the community, employers, family, friends and clients. (1)

Our approach in this paper is to set the scene by providing basic frequencies to responses in each scenario, followed by an analysis of themes elicited from respondents during the focus groups. Our immediate objective is to provide representative interviewee (that is, respondent) commentary designed to throw some light on the major choices of those respondents in the first year of the main quantitative survey. (2) Note that these focus groups were conducted some months after the quantitative analyses, and in particular after respondents had left law school. All respondents were, by that stage, working within a variety of legal workforce environments. In this analysis, it must be stressed, we have not attempted to match and compare individual respondents' comments with their earlier choices in the quantitative survey. That task awaits the longitudinal analysis now under way for the whole period of data collection during the three-year study.

Lateral strength of zero bond masonry walls subjected to wind loads

Masonry walls are usually laid with the individual masonry units along a course overlapping units in the course below. Commonly, the perpend joints in the course occur above the mid-points of the units below to form a ‘half-bond’ or above a third point to form a ‘third-bond’. The amount of this overlap has a profound influence on the strength of a wall supported on three or four sides, where lateral pressures from wind cause combined vertical and horizontal flexure. Where masonry units are laid with mortar joints, the torsional shear bond resistance between the mortar and overlapping units largely determines the horizontal flexural strength. If there is zero bond strength between units, then the horizontal flexural strength is derived from the frictional resistance to torsion on the overlapping bed-faces of the units. This thesis reports a theoretical and experimental investigation into the frictional properties of overlapping units when subjected to combinations of vertical and horizontal moments and vertical axial compression. These basic properties were used to develop a theory to predict the lateral strength of walls supported on two, three or four sides. A plastic theory of behaviour was confirmed by experiment. The theory was then used to determine maximum unbraced panel sizes for particular boundary conditions. Design charts were developed to determine temporary bracing requirements for panels during construction.

Intersection and partition graphs

This thesis reviews previous work done on both general partition graphs and existential partition graphs, which are a generalised form of general partition graphs, and extends some of the results.

Single molecule conductance through rigid norbornylogous bridges with zero average curvature

A new homologous series of norbornylogous (NB) bridges has been synthesized in which the average curvature of the bridges is very small. The molecules are rigid and have two thiol moieties at each end to allow them to form self-assembled monolayers (SAMs) and to connect to two gold electrodes to form a molecular junction. The SAMs formed were characterized using electrochemistry to determine the surface coverage of molecules on gold surface and to provide an indication of the packing of the NB bridges while ellipsometry and X-ray photoelectron spectroscopy (XPS) were used to provide an indication of the SAM thickness and orientation. Single molecule conductance of NB bridges was measured as a function of the molecular length. The conductance was found to decrease exponentially with the length with a decay constant that is exactly correlated with photoelectron transfer and other studies at the multiple molecule level. The molecule−electrode contact resistance was determined and compared with that of related alkanedithiol molecular junctions.