Rapid water quality characterization for chlorine demand and THM formation in drinking waters

The quality of drinking water generally deteriorates when it is delivered through a distribution system due to the decay of disinfectant, which subsequently allows the re-growth of microorganisms in the distribution system in addition to the formation of trihalomethane (THM). Therefore, a model which describes the changes that occur in the water quality in the distribution system is needed to determine whether to enhance the treatment processes or to improve the distribution system so that microbiological criteria are met. In this paper the chlorine decay kinetics and THM formation in treated water is modeled considering the reaction of chlorine with fast and slow reacting organic and nitrogenous compounds which are present in that water. The treated water was also passed through three types of resins to fractionate very hydrophobic acids (VHA), slightly hydrophobic acids (SHA), hydrophilic charged (CHA) and hydrophilic neutral (NEU) compounds which are present in the water. Chlorine decay tests were conducted on the effluents emerging from the resins to evaluate the chlorine demand and THM formation potential of those organic fractions. The model shows that the CHA presented in the waters has a very high THM formation potential (around 62% of the THM produced). VHA, NEU and CHA contributed to chlorine demand in the water.

Impact of past and future residential housing development patterns on energy demand and related emissions

The continued outward growth from a central business district has been the dominant characteristic of most cities in Australia. However, this feature is seen as unsustainable and alternative scenarios to contain the outward growth are being proposed. Melbourne is currently grappling with this issue while simultaneously trying to reduce per capita greenhouse gas emissions. Housing size, style and its location are the three principal factors which determine the emissions from the residential sector. This paper describes a methodology to assess the combined impact of these factors on past and possible future forms of residential development in Melbourne. The analysis found that the location of the housing and its size are the dominant factors determining energy use and greenhouse gas emissions.

Forecasting construction demand : a vector error correction model with dummy variables

Modelling the level of demand for construction is vital in policy formulation and implementation as the construction industry plays an important role in a country’s economic development process. In construction economics, research efforts on construction demand modelling and forecasting are various, but few researchers have considered the impact of global economy events in construction demand modelling. An advanced multivariate modelling technique, namely the vector error correction (VEC) model with dummy variables, was adopted to predict demand in the Australian construction market. The results of prediction accuracy tests suggest that the general VEC model and the VEC model with dummy variables are both acceptable for forecasting construction economic indicators. However, the VEC model that considers external impacts achieves higher prediction accuracy than the general VEC model. The model estimates indicate that the growth in population, changes in national income, fluctuations in interest rates and changes in householder expenditure all play significant roles when explaining variations in construction demand. The VEC model with disturbances developed can serve as an experimentation using an advanced econometrical method which can be used to analyse the effect of specific events or factors on the construction market growth.

Demand drives up TERs and threatens equity

Strong demand could help the government’s participation targets while simultaneously undermining equity targets.

Auditor independence : shared meaning between the demand and supply sides of the audit services market?

Purpose – The purpose of the paper is to examine the extent to which there is shared meaning of the concept of auditor independence between the three major groups of parties on the demand and supply sides of the audit services market – auditors, financial report preparers and financial report users.

Design/methodology/approach – The paper utilises the measurement of meaning framework (semantic differential analysis) originally proposed by Osgood et al. in 1957. The framework is used to investigate the extent to which there is shared meaning (agreement in interpretations) of the independence concept, in response to alternative audit engagement case contexts, between key parties to the financial reporting communication process. The study's research data was collected in the period March 2004-May 2005.

Findings – Findings indicate a robust and stable single-factor cognitive structure within which the research participants interpret the connotative meaning of the auditor independence concept. An analysis of the experimental cases finds similarities in connotations (interpretations) of an audit firm's independence for the participant groups for most cases, with the exception of cases involving the joint provision of audit and non-audit (taxation) services.

Research limitations/implications – The usual external validity threat that applies to experimental research generally applies to the study. That is, the results may not be generalisable to settings beyond those examined in the study. An important implication of the study is that it emphasises the continuing problematic nature of the joint provision of audit and non-audit services, even in situations where the non-audit services comprise only traditional taxation services.

Originality/value – The study is the first to examine the concept of auditor independence by means of the Osgood et al. measurement of meaning research framework using, as research participants, the three major groups on the demand and supply sides of the audit services market.

Critical uncertainty factors for efficient allocation of demand risk in privately financed public infrastructure projects in Australia

Risk allocation in privately financed public infrastructure projects, which are mainly referred as public-private partnership (PPP) projects, is a challenging job due to the nature of incomplete contracting. Among the various risks that may eventually materialise, demand risk is one of the major challenges that PPPs face. Choosing a risk allocation strategy could be viewed as the process of deciding the proportion of risk management responsibility between public and private partners based on a series of characteristics of risk management service transaction in question. These characteristics are more or less related to the various uncertainty factors. In this study, various uncertainty factors have been examined in order to achieve efficient allocation of demand risk and minimise risk management-related costs in a long-term view. Critical uncertainty factors have been identified through an industry-wide survey in Australia. Future research directions are also set out.