International Experience with Contractor Driven BOT Concessions

The BOT approach to building and financing infrastructure projects has been used for, among others, toll roads and bridges, power plants, port facilities, transmission lines and water supply systems. A number of concessions are contractor drive. The paper lists a set of best international BOT practices and a case has been designed to illustrate the points made

Ecological Benchmarking to Explore Alternative Fishing Schemes to Protect Endangered Species by Substitution: The Danish Demersal Fishery in the North Sea

The cod stock in the North Sea is threatened by overexploitation. To recover this fishing stock, pressure needs to be reduced. This implies that catch compositions with small amounts of cod are preferred by public policy makers. The present analysis assesses the technological efficiency of fishing trips in terms of the substitution possibilities away from cod by considering landings of cod as an undesirable output. A conservative non-parametric frontier technology approach imposing minimal assumptions and based on directional distance functions is applied to explore alternative fishing activities for Danish gill netters operating in the North Sea with the goal of reducing cod catches. Since performance on different fishing trips may be influenced by the operating environment, a four-stage approach is applied to correct for exogenous factors (Fried et al. (1999)). The corrected directional distance function efficiency scores reveal the behavioural inefficiencies, i.e., prospects for decreasing the catch of cod while catch of other species are increased.Capacity, Directional distance function, Fisheries, Output Substitution

Constraints on the relative sizes of intervening Mg II-absorbing clouds and quasar emitting regions

Context: A significantly higher incidence of strong (rest equivalent width W_r > 1 {\AA}) intervening Mg II absorption is observed along gamma-ray burst (GRB) sight-lines relative to those of quasar sight-lines. A geometrical explanation for this discrepancy has been suggested: the ratio of the beam size of the source to the characteristic size of a Mg II absorption system can influence the observed Mg II equivalent width, if these two sizes are comparable. Aims: We investigate whether the differing beam sizes of the continuum source and broad-line region of Sloan Digital Sky Survey (SDSS) quasars produce a discrepancy between the incidence of strong Mg II absorbers illuminated by the quasar continuum region and those of absorbers illuminated by both continuum and broad-line region light. Methods: We perform a semi-automated search for strong Mg II absorbers in the SDSS Data Release 7 quasar sample. The resulting strong Mg II absorber catalog is available online. We measure the sight-line number density of strong Mg II absorbers superimposed on and off the quasar C IV 1550 {\AA} and C III] 1909 {\AA} emission lines. Results: We see no difference in the sight-line number density of strong Mg II absorbers superimposed on quasar broad emission lines compared to those superimposed on continuum-dominated spectral regions. This suggests that the Mg II-absorbing clouds typically observed as intervening absorbers in quasar spectra are larger than the beam sizes of both the continuum-emitting regions and broad line-emitting regions in the centers of quasars, corresponding to a lower limit of the order of 10^17} cm for the characteristic size of a Mg II absorbing cloud.Comment: 10 pages, 5 figures. Edit: fixed a missing cross-referenc

Air flow study in a two branches manifold

This project consists on a cooling system for a wind turbine generator. The main concept used to cool the generator is based on a manifold, which consists in an arrangement of pipes used to redistribute the flow of a fluid or gas, typically from a single inlet to a number of outlets, or vice versa. The first idea was to design a manifold with an inlet and four outlets using an equation solver program called EES, SolidWorks Flow Simulation as an application of computational fluid dynamics (CFD) analysis and a wooden model built and tested, and try to get the total control of the system. A first step has been to carry out all the calculations for a two branch model. This has given us a general idea of how the flow works and how it is distributed between the branches, and this two branches model (instead of four) simplifies the calculations of the model at first. This model, which its main branch is 30 mm wide and the outlet branches widths are 19.5 and 21.5 mm, has been introduced to an EES program, designed in SolidWorks and built in wood to obtain the pressures, velocities and flows for the circulating fluid along the conduits. Once the results for the three methods have been obtained, these has been analyzed and compared between them to draw some conclusions about the similarities or differences of the data from the three methods. After the first analysis we have decided to build again a two branches model but with narrower conduits, of 5 mm both the main branch and the outlet branches. This second model has been designed to see if the flow behaves the same way when it circulates through narrow conduits. Here we have had to design a new method to measure the parameters inside the thin conduits. This method, which we called “Sphere method”, consists of a small lead ball which moves more or less depending on the pressure applied on its surface. Once compared to the other two computational methods, it has been tested in the wide branches model and compared to the results obtained there measuring with a Pitot tube, and has resulted to be more accurate than expected, so we have decided to enhance it by working with more lengths to calculate the velocity profile curve and improve the calibration of the threads so the results were even more precise. In other matters we have studied the pressure loss in a tubular pipe which is narrower in the middle. This study has been performed using three computer programs; the already known EES and SolidWorks Flow Simulation Studio, and CFDesign. This last comparison has been expected to show the differences between three methods based on theoretical calculations

Comparison of markets for organic food in six EU states.

This report was presented at the UK Organic Research 2002 Conference. Recent research confirms that the decision to convert is now highly influenced by financial incentives arising from EU regulations but the exact mix of incentives depends on prevailing government policies and access to premium markets so that the organic sector in most countries is now referred to as either government-led or market-driven. The objective of the paper is to compare development of the sector along these two polarities but set within the context of "common elements of interest" within new agrifood methodologies: time, space, power, and meaning (Cooke, Uranga and Etxebarria 1998; Morgan and Murdoch 2000). The paper presents preliminary findings relating to six EU States: UK, Ireland, Austria, Denmark, Portugal and Italy, and through the application of "worlds of production" to market outlets and suggests discourses that define these outlets. The analysis aims to inform the further study of farmer marketing decisions and practices

Ecological Benchmarking to Explore Alternative Fishing Schemes: The Danish Demersal Fishery in the North Sea

The cod stock in the North Sea is threatened by overexploitation. To recover this fishing stock, pressure needs to be reduced. This implies that catch compositions with small amounts of cod are preferred by public policy makers. The present analysis assesses the technological efficiency of fishing trips, considering landings of cod as an undesirable output. A non-parametric frontier technology approach based on directional distance functions is applied to explore alternative fishing activities for Danish gill netters operating in the North Sea with the goal of protecting the cod stock. Since the performance observed on different fishing trips may be under influence of the external operating environment, a four-stage approach introduced by Fried et al. (1999) is applied to correct for such exogenous factors. The corrected directional distance function efficiency scores reveal the behavioural inefficiencies, i.e., prospects for decreasing the catch of cod while catch of other species are increased