Abbas El-Zein

The development and application of multi-criteria decision-making tool with consideration of uncertainty: the selection of a management strategy for the bio-degradable fraction in the municipal solid waste.

A modified version of the multi-criteria decision aid, ELECTRE III has been developed to account for uncertainty in criteria weightings and threshold values. The new procedure, called ELECTRE-SS, modifies the exploitation phase in ELECTRE III, through a new definition of the pre-order and the introduction of a ranking index (RI). The new approach accommodates cases where incomplete or uncertain preference data are present. The method is applied to a case of selecting a management strategy for the bio-degradable fraction in the municipal solid waste of Sydney. Ten alternatives are compared against 11 criteria. The results show that anaerobic digestion (AD) and composting of paper are less environmentally sound options than recycling. AD is likely to out-perform incineration where a market for heating does not exist. Moreover, landfilling can be a sound alternative, when considering overall performance and conditions of uncertainty.

Sustainability and Ethics as Decision-Making Paradigms in Engineering Curricula.

Purpose – The aim of this paper is to explore the rationale for teaching sustainability and engineering ethics within a decision‐making paradigm, and critically appraise ways of achieving related learning outcomes.Design/methodology/approach – The paper presents the experience of the School of Civil Engineering at the University of Sydney in teaching environmental sustainability and engineering ethics to third‐year undergraduate students. It discusses the objectives of the course and the merits and drawbacks of incorporating ethics and sustainability in the same teaching framework. In addition, it evaluates ways of incorporating theoretical and applied perspectives on sustainability.Findings – Ethics and sustainability overlap but do not coincide; incorporating them in the same engineering course can be effective, provided that points of linkage are clearly recognized in the syllabus, a suitable combination of theory and practical applications is drawn upon and adequate teaching methods, including decisio...

Strategies for the municipal waste management system to take advantage of carbon trading under competing policies: The role of energy from waste in Sydney

Climate change is a driving force behind some recent environmental legislation around the world. Greenhouse gas emission reduction targets have been set in many industrialised countries. A change in current practices of almost all greenhouse-emitting industrial sectors is unavoidable, if the set targets is to be achieved. Although, waste disposal contributes around 3% of the total greenhouse gas emissions in Australia (mainly due to fugitive methane emissions from landfills), the carbon credit and trading scheme set to start in 2010 presents significant challenges and opportunities to municipal solid waste practitioners. Technological advances in waste management, if adopted properly, allow the municipal solid waste sector to act as carbon sink, hence earning tradable carbon credits. However, due to the complexity of the system and its inherent uncertainties, optimizing it for carbon credits may worsen its performance under other criteria. We use an integrated, stochastic multi-criteria decision-making tool that we developed earlier to analyse the carbon credit potential of Sydney municipal solid waste under eleven possible future strategies. We find that the changing legislative environment is likely to make current practices highly non-optimal and increase pressures for a change of waste management strategy.

Health and ecological sustainability in the Arab world: a matter of survival

Discussions leading to the Rio+20 UN conference have emphasised the importance of sustainable development and the protection of the environment for future generations. The Arab world faces large-scale threats to its sustainable development and, most of all, to the viability and existence of the ecological systems for its human settlements. The dynamics of population change, ecological degradation, and resource scarcity, and development policies and practices, all occurring in complex and highly unstable geopolitical and economic environments, are fostering the poor prospects. In this report, we discuss the most pertinent population-environment-development dynamics in the Arab world, and the two-way interactions between these dynamics and health, on the basis of current data. We draw attention to trends that are relevant to health professionals and researchers, but emphasise that the dynamics generating these trends have implications that go well beyond health. We argue that the current discourse on health, population, and development in the Arab world has largely failed to convey a sense of urgency, when the survival of whole communities is at stake. The dismal ecological and development records of Arab countries over the past two decades call for new directions. We suggest that regional ecological integration around exchange of water, energy, food, and labour, though politically difficult to achieve, offers the best hope to improve the adaptive capacity of individual Arab nations. The transformative political changes taking place in the Arab world offer promise, indeed an imperative, for such renewal. We call on policy makers, researchers, practitioners, and international agencies to emphasise the urgency and take action.

Groundwater pollution by organic compounds: a two-dimensional analysis of contaminant transport in stratified porous media with multiple sources of non-equilibrium partitioning

Transport of pollutants in soil and groundwater often occurs in stratified media under non-equilibrium conditions. Confined aquifers are usually bounded by low-permeability layers of soil which have been shown to exert a significant influence on the fate of contaminants in groundwater. Numerical solutions of transport equations have usually been restricted to single layers and have included single sources of non-equilibrium processes or none at all. The effect of soil stratification itself has sometimes been reduced to a transport-based non-equilibrium process. A boundary element solution of the transport equations in the Laplace domain is extended to include multiple sources of non-equilibrium processes in saturated media under the assumption of rate-limited mass transfer. Green functions accurately model infinite and semi-infinite domains such as soils and Laplace transforms remove the need for time-stepping and the associated numerical complexity. The proposed numerical technique is validated by comparing its results to analytical solutions. Its scope is illustrated through a case study of a sand aquifer bounded by less permeable layers of silt, and infiltrated by pollutants from a neighbouring lake. Copyright

Who's been left behind? Why sustainable development goals fail the Arab world

1–5 Evidence of persistent infectious disease in low-income and middle-income Arab countries exists, alongside increased prevalence of non-communicable diseases in all Arab countries, 6,7 high out-of-pocket health expenditure, 8 poor access to safe water, as well as violent confl ict, persistent foreign interventions, and high levels of social and political fragmentation that result in weak health systems and diminished rights to health. 9 Two sets of indicators, with important implications for health and development, are strikingly extreme in the Arab region (appendix). First, the Arab world has ten times the per person world average number of refugees and, in the Gulf Cooperation Council (GCC) countries, the highest number of international migrant workers as a percentage of the population at more than ten times the world average. Second, the Arab world has high levels of militarisation, with weapons imports per person at more than four times the world average. Additionally, the Arab world has the lowest ratios of health to military expenditures at less than one-fi fth of the world average.

Assessment of Vulnerability to Climate Change Using Indicators: Methodological Challenges

Climate change vulnerability assessment (CCVA) can help policy makers incorporate climate futures in planning. We discuss some of the most important methodological challenges facing CCVA, including geographical and temporal scales, aggregation, and nonlinearity. CCVA literature is large and multidisciplinary and appears to stem from a number of different paradigms (risk assessment, natural disaster management, urban planning, etc.). It is therefore difficult to elicit major directions, findings, and methodologies from this body of work. We study a sample of peer-reviewed CCVA publications and investigate the extent to which the CCVA literature is foregrounding and engaging with these methodological problems. We find that: 1. Critical scrutiny of prevalent assessment methodologies and development of new ones remain limited since only 10 % of the studies focus on such issues. This is despite the fact that many scholars have raised questions about the methodological aspects of vulnerability assessment. 2. Among the studies that aggregate indicators and consider both the biophysical and socioeconomic processes generating vulnerability, 59 % use methods based on multiple attribute utility theory (MAUT) such as arithmetic mean, geometric mean, or GIS-based MAUT, approaches that have strict theoretical requirements which are hardly met in the context of CCVA. 3. Although a number of theoretical papers have argued that indicator-based vulnerability assessment is likely to be most valid at smaller rather than larger geographical scales, only 17 % of studies are conducted at local scale.

Mechanical and flow behaviours and their interactions in coalbed geosequestration of CO2

Studying gas transport mechanisms in coal seams is crucial in determining the suitability of coal formations for geosequestration and/or CO2-enhanced coal bed methane recovery (ECBM), estimating CO2 storage capacity and recoverable volume of methane, and predicting the long-term integrity of CO2 storage and possible leakages. Due to the dual porosity nature of coal, CO2 transport is a combination of viscous flow and Fickian diffusion. Moreover, CO2 is adsorbed by the coal which leads to coal swelling which can change the porous structure of coal and consequently affects the gas flow properties of coal, i.e. its permeability. In addition, during CO2 permeation, the coal seam undergoes a change in effective stress due to the pore pressure alteration and this can also change the permeability of the coal seam. In addition, depending on the in situ conditions of the coal seam and the plan of the injection scheme, carbon dioxide can be in a supercritical condition which increases the complexity of the problem. We provide an overview of the recent studies on porous structure of coal, CO2 adsorption onto coal, mechanisms of CO2 transport in coalbeds and their measurement, and hydro-mechanical response of coal to CO2 injection and identify opportunities for future research.

Groundwater pollution by organic compounds : A three-dimensional boundary element solution of contaminant transport equations in stratified porous media with multiple non-equilibrium partitioning

Industrial contaminants and landfill leachates, particularly those with high organic content, may migrate into groundwater streams under conditions of non-equilibrium partitioning. These conditions may either be induced by time-dependent sorption onto the soil skeleton and intra-sorbent diffusion in the soil matrix, or by heterogeneous advective fields within the pore. These processes are known as chemical and physical non-equilibrium processes respectively, and may result in significant deviations from the paths predicted by steady-state partitioning assumptions. In addition, multi-directional soil properties, soil stratification and complex geometries of the pollution source may require a full three-dimensional analysis for accurate contamination prediction. A three-dimensional boundary element solution of the time-dependent diffusive/advective equation in non-homogeneous soils with both physical and chemical non-equilibrium processes is developed. Saturated conditions and rate-limited mass transfer are assumed. The Laplace transform removes the need for time-stepping and the associated numerical complexity, and the use of Greens functions yields accurate solutions of infinite and semi-infinite domains such as soils as well as media with finite dimensions. The solution requires boundary discretization only and can therefore be a valuable tool in bio-remediation and landfill design where different geometries, soil properties and pollutant loads may be analysed at low cost. The proposed technique is validated by comparing its predictions to analytical solutions obtained for different types of soil and contaminant sources. The scope of the method is illustrated by analysing the contamination of multi-layered soils by a neighbouring river and a surface source.

Can action on health achieve political and social reform

Public debate about health is rare in Arab countries. But getting the social and political issues underlying health problems onto the agenda could have wider effects on the regions political stagnation