Modeling and optimization of production and distribution of drinking water at VMW

We develop and discuss an operational planning model aiming at minimizing production and distribution costs in large drinking water networks containing buffers with free inflow. Modeling drinking water networks is very challenging due of the presence of complex hydraulic constraints, such as friction losses and pump curves. Non-linear, non-convex constraints result from the relationships between pressure and flow in power terms. Also, binary variables are needed to model the possibility of free inflow or re-injection of water at reservoirs. The resulting model is thus a non-convex Mixed-Integer Non-Linear Program (MINLP). A discrete-time setting is proposed to solve the problem over a finite horizon made of several intervals. A commercial solver, BONMIN, suited for convex MINLP models is used to heuristically solve the problem. We are able to find a good solution for a small part of an existing network operated by the Vlaamse Maatschappij voor Watervoorziening (VMW), a major drinking water company in Flanders

Does it matter which weather data you use in energy simulations?

Users of energy simulation programs often have a variety of weather data from which to choose--from locally recorded, measured weather data to preselected typical years--a bewildering range of options. In the last two years, several organizations have developed several new typical weather data sets including WYEC2, TMY2, CWEC, and CTZ2. Unfortunately, neither how these new data influence energy simulation results nor how they compare to existing typical data sets or actual weather data is well documented. In this paper, the authors present results from the DOE-2.1E hourly energy simulation program for a prototype office building as influenced by local measured weather data for multiple years and several weather data sets for a set of North American locations. They compare the influence of the various weather data sets on simulated annual energy use and energy costs. Statistics for temperature, solar radiation, and heating and cooling degree days for the different locations and data sets are also presented. Where possible, they explain the variation relative to the different designs used in developing each data set. They also show the variation inherent in actual weather data and how it influences simulation results. Finally, based on these results, they answer the question--does it really matter which weather data you use

Estimating the functional form for the density dependence from life history data

Two contrasting approaches to the analysis of population dynamics are currently popular: demographic approaches where the associations between demographic rates and statistics summarizing the population dynamics are identified; and time series approaches where the associations between population dynamics, population density, and environmental covariates are investigated. In this paper, we develop an approach to combine these methods and apply it to detailed data from Soay sheep (Ovis aries). We examine how density dependence and climate contribute to fluctuations in population size via age- and sex-specific demographic rates, and how fluctuations in demographic structure influence population dynamics. Density dependence contributes most, followed by climatic variation, age structure fluctuations and interactions between density and climate. We then simplify the density-dependent, stochastic, age-structured demographic model and derive a new phenomenological time series which captures the dynamics better than previously selected functions. The simple method we develop has potential to provide substantial insight into the relative contributions of population and individual-level processes to the dynamics of populations in stochastic environments

Evidence that high von Willebrand factor and low ADAMTS-13 levels independently increase the risk of a non-fatal heart attack

Background: A disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS-13) may influence von Willebrand factor (VWF) levels and consequently the risk of myocardial infarction (MI). Moreover, ADAMTS-13 influences hemostatic plug formation in mouse models. We therefore studied their associations in the Glasgow MI Study (GLAMIS). Methods and results: We measured ADAMTS-13 and VWF antigen levels by ELISAs in stored plasma from a case–control study of 466 MI cases and 484 age- and sex-matched controls from the same north Glasgow population. There was no correlation between ADAMTS-13 and VWF levels in cases or controls. ADAMTS-13 levels correlated positively with serum cholesterol and triglycerides and body mass index, and negatively with high-density lipoprotein-cholesterol. VWF levels correlated with age, fibrinogen and C-reactive protein. In multivariable analyses including risk factors, VWF correlated positively with risk of MI, and ADAMTS-13 correlated negatively with risk of MI. These associations were independent of each other. The association of ADAMTS-13 with risk of MI was observed only in multivariable analysis. Conclusions: VWF and ADAMTS-13 levels were not associated in this study, and showed associations with MI risk in opposite directions but of similar strength. The association of ADAMTS-13 with MI is influenced by lipid levels, and consequently requires further investigation

Highly-Parallel, Highly-Compact Computing Structures Implemented in Nanotechnology

In this paper, we describe work in which we are evaluating how the evolving properties of nano-electronic devices could best be utilized in highly parallel computing structures. Because of their combination of high performance, low power, and extreme compactness, such structures would have obvious applications in spaceborne environments, both for general mission control and for on-board data analysis. However, the anticipated properties of nano-devices mean that the optimum architecture for such systems is by no means certain. Candidates include single instruction multiple datastream (SIMD) arrays, neural networks, and multiple instruction multiple datastream (MIMD) assemblies

Researching prisoner experiences with prison officers: an action research inspired approach

This article reports on research that incorporated action research-inspired dimensions on a project conducted in three maximum-security prisons in England. The project was aimed at collecting ethnographically informed data on prisoner experiences, at developing a method by which such data could be systematically and routinely collected by prison staff and at facilitating opportunities for prison officers to understand the ‘pains of imprisonment’ from the perspectives of prisoners. The challenges and limitations of the project are discussed, with particular reference to the paradox of participation and the role of power relations within prisons and within the research process. It is suggested that despite the inherent difficulties of attempting a participative approach with more powerful actors, facilitating change on a larger scale may be best served by developing a ‘pedagogy of the oppressors’ alongside a ‘pedagogy of the oppressed’

Assessment of the Technical Potential for Achieving Zero-Energy Commercial Buildings: Preprint

The U.S. Department of Energy's Building Technologies Program has adopted the goal of making zero-energy commercial buildings (ZEBs) marketable by 2025. The National Renewable Energy Laboratory conducted an assessment of the entire commercial sector to evaluate the technical potential for meeting this goal with technology available in 2005 and projected forward to possible technology improvements for 2025. The analysis looked at the technical feasibility of ZEBs, limitations in market penetration and utility grid structures notwithstanding

Method for Planning Graduate Programs in Construction Management

University programs in Western countries must be accredited, and although several detailed conceptual methods have aimed to design new programs, no specific quantitative tools are currently available. The purpose of this paper is to describe a method to plan, design, or improve graduate degree programs based on selected requirements and market demands. This method involves two metrics, which are later combined into a final index. The first metric is the completeness index that evaluates the extent to which certain programs cover a discipline, in this case, construction management, according to a model using two variables: infrastructure life cycle and organizational breakdown. The second metric is the adequacy index, which measures how a program addresses the previously identified market demands. The final indicator (summary index) relates both indexes in a plot chart. In this study, the applicability of the method is illustrated by a sample of 21 construction management programs from prestigious universities and a survey of the Spanish construction industry. It can be applied in practice, not only in the construction management field, but also in other fields with an appropriate theoretical model that maps each field of knowledge and exploratory data that highlight the demands of each specific market.Pellicer Armiñana, E.; Yepes Piqueras, V.; Ortega Llarena, AJ. (2013). Method for Planning Graduate Programs in Construction Management. Journal of Professional Issues in Engineering Education and Practice. 139(1):33-41. doi:10.1061/(ASCE)EI.1943-5541.0000120S3341139