Growth and equity effects of changing demographic structures in the Netherlands: simulations within a social accounting matrix

"This paper deals with the economic consequences of a changing demography in an industrialized country, namely the Netherlands. The analytical framework chosen is that of general equilibrium as statistically given by the social accounting matrix (SAM) in which we introduce households by size for the present economic demographic situation (1981) and for a future simulated situation (2010) featuring in particular a relative increase in one-person households (individualization). The income (output) multipliers of both SAMs show a positive growth bias towards three and more person households and towards mining, public utilities, trade and banking."     

Application of nitrogen and phosphorus criteria for streams in agricultural landscapes

Efforts to control eutrophication of water resources in agriculturally dominated ecosystems have focused on managing on-farm activities to reduce nutrient loss; however, another management measure for improving water quality is adoption of environmental performance criteria (or 'outcome-based standards'). Here, we review approaches for setting environmental quality criteria for nutrients, summarize approaches developed in Canada for setting 'ideal' and 'achievable' nutrient criteria for streams in agricultural watersheds, and consider how such criteria could be applied. As part of a 'National Agri-Environmental Standards Initiative', the Government of Canada committed to the development of non-regulatory environmental performance standards that establish total P (TP) and total N (TN) concentrations to protect ecological condition of agricultural streams. Application of four approaches for defining ideal standards using only chemistry data resulted in values for TP and TN spanning a relatively narrow range of concentrations within a given ecoregion. Cross-calibration of these chemically derived standards with information on biological condition resulted in recommendations for TP and TN that would likely protect aquatic life from adverse effects of eutrophication. Non-point source water quality modelling was then conducted in a specific watershed to estimate achievable standards, i.e. chemical conditions that could be attained using currently available and recommended management practices. Our research showed that, taken together, short-term achievable standards and ultimate ideal standards could be used to set policy targets that should, if realized, lower N and P concentrations in Canadian agricultural streams and improve biotic condition.     

Influence of hydraulic retention time on UASB post-treatment with UF membranes

A pilot UASB reactor coupled with an external ultrafiltration (UF) membrane was operated under three different hydraulic retention times (HRT) for domestic wastewater treatment. The aim was to assess the HRT influence on system performance and fouling. The highest concentrations of COD, total solids, extracellular polymeric substances (EPS) and soluble microbial products (SMP) in UASB effluent and permeate were found when the UASB reactor was operated under the lowest HRT studied (4 hours); although the fulfillment of Mexican Standard for wastewater reclamation was not compromised. This fact could be attributed to the higher shear stress forces inside the UASB reactor when it was operated at low HRT, which promoted the release of biopolymeric substances in its effluent. Besides, the fouling propensity in the UASB effluent was worsened with HRT reduction, by increasing the fouling rate and the specific cake resistance. Based on these results, it is recommended to avoid operating the UASB reactor at low HRTs (less than 4 hours) in order to control SMP and EPS fouling potential. The results presented also suggest that HRT reduction has a detrimental effect on performance and fouling.     

Opportunities for public water utilities in the market of energy from water

An inventory is made of the possibilities to recover sustainable energy from the water cycle by identifying different water flows in a municipal environment as a sustainable energy source. It is discussed what role public water utilities should play in the market of energy from water. This is done for Waternet, the public water utility of Amsterdam, by describing experiences on two practical applications for aquifer thermal energy storage and energy recovery from drinking water. The main conclusion is that public water utilities can substantially contribute to the production of sustainable energy, especially by making use of heat and cold from the water cycle. Public water utilities have the opportunity to both regulate and enter the market for energy from water.     

The use of CFD modelling to optimise measurement of overflow rates in a downstream-controlled dual-overflow structure

The measurement of the flow through complex combined sewer overflow structures in the frame of automated monitoring remains difficult. In this paper, a methodology based on the use of computational fluid dynamics (CFD) modelling in order to improve the instrumentation of a downstream-controlled dual-overflow structure is presented. The dual-overflow structure is composed of two combined sewer overflows (CSOs) connected by a rectangular channel and controlled by a downstream gate located at the entry of the Meyzieu waste water treatment plant (close to Lyon, France). The analysis of the CFD results provides: (i) a better understanding of the interaction between the two CSOs--that means the hydraulic operation, the hydrodynamic behaviour, the backflow effect--and (ii) an ability to optimise the location of the water depth sensor. The measured water depth is used to assess the overflow rate by means of a numerical relationship. Uncertainties are also assessed.     

Is this the right time to come out? Case study

In this fictional case study, Adam Lawson is a promising young associate at Kirkham McDowell Securities, a St. Louis underwriting and financial advisory firm. Recently, Adam helped to bring in an extremely lucrative deal, and soon he and a few other associates will be honored for their efforts at the firm's silver anniversary dinner. George Campbell, vice president in mergers and acquisitions, is caught unprepared when Adam tells him that, after serious reflection, he has decided to bring his partner, Robert Collins, to the banquet. George is one of Adam's biggest supporters at the firm, and he personally has no problem with Adam being gay. But it is one thing for Adam to come out of the closet at the office. It is quite another to do so at a public company-client event. After all, Kirkham McDowell's client roster includes some very conservative companies--one of the country's largest defense contractors, for example. George is concerned with how Adam's openness about his sexual orientation will play with their clients and, as a result, how senior management will react. Adam has not come to George for permission to bring Robert to the dinner. But clearly Adam wants some sort of response. George has never faced sexual diversity issues in the workplace before, and there is no company policy to guide him. Just how negative an effect could Robert have on Adam's career with the firm and the firm's relationship with its clients? Isn't it possible that even the firm's most conservative clients will simply decide that Adam's choice of guest is a personal matter--not a business one?(ABSTRACT TRUNCATED AT 250 WORDS)