The use of geographic information systems for the optimal location of biomass power plants in the Madrid Community (Spain)

This article has been extracted from the results of a thesis entitled “Potential bioelectricity production of the Madrid Community Agricultural Regions based on rye and triticale biomass.” The aim was, first, to quantify the potential of rye (Secale Cereale L.) and triticale ( Triticosecale Aestivum L.) biomass in each of the Madrid Community agricultural regions, and second, to locate the most suitable areas for the installation of power plants using biomass. At least 17,339.9 t d.m. of rye and triticale would be required to satisfy the biomass needs of a 2.2 MW power plant, (considering an efficiency of 21.5%, 8,000 expected operating hours/year and a biomass LCP of 4,060 kcal/kg for both crops), and 2,577 ha would be used (which represent 2.79% of the Madrid Community fallow dry land surface). Biomass yields that could be achieved in Madrid Community using 50% of the fallow dry land surface (46,150 ha representing 5.75% of the Community area), based on rye and triticale crops, are estimated at 84,855, 74,906, 70,109, 50,791, 13,481, and 943 t annually for the Campiña, Vegas, Sur Occidental, Área Metropolitana, Lozoya-Somosierra, and Guadarrama regions. The latter represents a bioelectricity potential of 10.77, 9.5, 8.9, 6.44, 1.71, and 0.12 MW, respectively

Un análisis estratégico del sector de las telecomunicaciones

Este trabajo de investigación pretende identificar las principales características estratégicas del sector de telecomunicaciones, con especial énfasis en la situación actual y posible evolución futura de las empresas. Se tomará como punto de partida el periodo precrisis 2004-2008 y se comparará con la situación actual 2009-2014. Dada la coyuntura actual tras la crisis financiera de los últimos cinco años y las expectativas de salida de la misma, en este estudio se realiza un análisis estratégico del sector de las comunicaciones que servirá de base para analizar futuras expansiones de este sector, una vez su-peradas las limitaciones económicas actuales. También se quiere resaltar las grandes incertidumbres asociadas a la aparición de las nuevas tecnologías móviles de banda ancha que han provocado un fuerte cambio tecnológico en el entorno de los operadores móviles. Este estudio comienza con una breve reseña histórica del sector y concluye con los principales cambios históricos, desafíos, riesgos y objetivos actuales del mismo, realizándose una segmentación de los principales operadores

Computing Efficient Financial Strategies: An Extended Compromise Programming Approach

This paper proposes a mathematical model to plan the financial strategy of a large company. The model links the philosophy of new behavioural economics with the multiple criteria decision making paradigm. Within this theoretical approach, the proposed model is supported by more realistic behavioral hypotheses. After formulating the initial multi-objective programming model, it has, due to its underlying computational difficulties, to be transformed into an easily computable extended compromise programming model. The functional and empirical potential of the model is illustrated with the help of a case study concerning a “stock market quoted” Spanish company operating in the energy sector. This paper shows how such an approach can open up new prospects for research linking economic problems with applied mathematic

Corporate social responsibility in portfolio selection: A "goal games" against nature approach

Nowadays, there is an uprising social pressure on big companies to incorporate into their decision-making process elements of the so-called social responsibility. Among the many implications of this fact, one relevant one is the need to include this new element in classic portfolio selection models. This paper meets this challenge by formulating a model that combines goal programming with "goal games" against nature in a scenario where the social responsibility is defined through the introduction of a battery of sustainability indicators amalgamated into a synthetic index. In this way, we have obtained an efficient model that only implies solving a small number of linear programming problems. The proposed approach has been tested and illustrated by using a case study related to the selection of securities in international markets

Three-dimensional modelling of calving processes on Johnsons Glacier, Livingston Island, Antarctica.

Iceberg calving is an important mass loss mechanism from ice shelves and tidewater glaciers for many mid and high-latitude glaciers and ice caps, yet the process is not well represented in prognostic models of ice dynamics. Benn and others (2007) proposed a calving criterion appropriate for both grounded and floating glacier tongues or ice shelves. This criterion assumes that the calving is triggered by the downward propagation of transverse surface crevasses, near the calving front, as a result of the extensional stress regime. The crevasse depth is calculated following Nye (1957), assuming that the base of a field of closely spaced crevasses lies at a depth where the longitudinal tensile strain rate tending to open the crevasse equals the creep closure resulting from the ice overburden pressure

Un modelo tridimensional de producción de icebergs: experimentos numéricos en el glaciar Johnsons, Isla Livingston, Antártida

Las leyes de producci´on de icebergs m´as usuales son: 1) la que considera que la tasa de producci´on de icebergs depende linealmente de la profundidad de agua en el frente glaciar, seg´un una ley obtenida mediante ajustes a observaciones de campo; y 2) aqu´ella en la que el criterio de producci´on de icebergs viene dado por la altura del glaciar sobre el nivel de flotaci´on. El principal problema de la primera es que las relaciones emp´ıricas var´ıan ampliamente de un glaciar a otro, y tambi´en var´ıan con el tiempo, lo que no las hace adecuadas para modelos evolutivos de glaciares, mientras que la mayor desventaja de la segunda es que su aplicaci´on queda restringida a glaciares con frente no flotante. El nuevo criterio de producci´on de icebergs propuesto recientemente por Benn et al. [2] considera que el mecanismo primario de la producci´on de icebergs es la propagaci´on vertical de las grietas superficiales desarrolladas cerca del frente como consecuencia del r´egimen de tensiones extensivas. Este criterio permite el desarrollo de lenguas glaciares flotantes y puede ser utilizado en modelos evolutivos de din´amica glaciar. Sus principales limitaciones son su car´acter bidimensional y la excesiva simplicidad de los modelos din´amicos empleados. Hemos desarrollado una extensi´on tridimensional de este criterio que resuelve el sistema de Stokes completo de la din´amica glaciar, superando as´ı las dos limitaciones mencionadas. Hemos aplicado este modelo al glaciar Johnsons, en Isla Livingston (Ant´artida), mostrando los resultados que, si consideramos la presencia de un cierto volumen de agua de fusi´on en las grietas, las predicciones del modelo se ajustan bastante bien a las observaciones. No obstante, se requieren mejoras en la ley de deslizamiento del glaciar sobre su lech

Ice thickness, internal structure and subglacial topography of Bowles Plateau ice cap and the main ice divides of Livingston Island, Antarctica, by ground-based radio-echo sounding

Ground-based radio-echo sounding studies of Livingston Island ice cap, Antarctica, were started in 1999 at Johnsons and Hurd glaciers, in Hurd Peninsula, close to the Spanish Antarctic Station Juan Carlos I. Radar profiling continued in 2000 and 2003 along the main ice divides of the ice cap and in the upper parts of Huron and another unnamed glacier, both draining Bowles ice plateau towards Moon Bay. More detailed radar studies on Bowles ice plateau were performed in December 2006 using an icepenetrating radar VIRL-6, with central frequency of 20 MHz, and a Ramac/GPR radar with 200 MHz antennae, intended for deep penetration to bedrock and shallow penetration to determine the firn layer thickness, respectively. The radar equipment was installed on two Nansen sledges and two pulkas towed by snowmobiles. Georeferencing of radar data was accomplished by using a GPS receiver working in stand-alone mode. The endpoints of the radar profiles were more accurately georeferenced using differential GPS. The data collected were used to construct the ice thickness, glacier surface and bedrock elevation maps and to estimate the average ice thickness and total ice volume of the plateau, as well as the spatial distribution of snow accumulation. For time-to-depth conversion, an average radio-wave velocity determined from common midpoint measurements at several locations in Hurd Peninsula was used. The thickest ice (550 m) was found in the upper part of Huron glacier. This thickness is almost twice the maximum thickness found along the main ice divides (330 m) and almost three times that found in Hurd Peninsula (200 m). The bedrock in two large areas in the northern and southern parts of the plateau, towards Moon Bay and Huntress glacier, lies below sea level, at depths down to -200 m, indicating that, should the ice cap fully disappear, several separated islands would likely appear, even if isostacic rebound is taken into account

Perspectives on prevention Issues, approaches and practices for tackling local crime problems

SIGLEAvailable from British Library Document Supply Centre-DSC:99/14792 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Optimum acceptability of telecommunications networks: a multi-criteria approach

This paper proposes an aggregated index of acceptability that can establish a "ranking" of the possible candidate hub cities in the design of a telecommunications network. The main advantages of the aggregated index proposed are the following: (a) it takes into account several wide-ranging design criteria, (b) its formulation is given by a lineal mathematical expression, (c) the procedure for calculating the index is very simple, and (d) the candidate hubs can be ranked differently depending on the aggregation structure of the criteria involved. Taking this considerations, the application of the proposed methodology can supplement the information supplied by more sophisticated multicriteria approaches based generally upon 0/1 goal programming. The theory presented is illustrated using a case study taken from the literature

Patient care in the community Community mental handicap nursing, 1992-93; summary information from Form KC58, England

Available from British Library Document Supply Centre-DSC:6412.86141(1992-93) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo