Suchergebnisse

Electro-optical and infrared (EO/IR) sensor models are useful tools that can facilitate understanding a system's behavior without expensive and time-consuming testing of an actual system. EO/IR models are especially important to the military industry where truth data is required but is sometimes impractical to obtain through experimentation due to expense or difficulties in procuring hardware. This work describes implementation of a focal plane array (FPA) model of charge-coupled device (CCD) and complementary metal-oxide semiconductor (CMOS) photodetectors as a component in the Air Force Institute of Technology (AFIT) Sensor and Scene Emulation Tool (ASSET). The FPA model covers conversion of photo-generated electrons to voltage and then to digital numbers. It incorporates sense node, source follower, and analog-to-digital converter (ADC) components contributing to gain non-linearities and includes noise sources associated with the detector and electronics such as shot, thermal, 1/f, and quantization noise. This thesis describes the higher fidelity FPA and electronics model recently incorporated into ASSET, and it also details validation of the improved model using EO/IR imager data collected with laboratory measurements. The result is an improved model capable of generating realistic synthetic data representative of a wide range of systems for use in new algorithm development and data exploitation techniques supporting a broad community of academic, commercial, and military researchers.

Research in lifestyle risks is becoming more and more important, particularly with reference to what is generally known as "unhealthy diets". The Law is now firmly established as a prominent instrument of Public Health. There are several distinctive methods of legal intervention targeted at counteracting overweight and promoting healthier lifestyles. In this paper we examine several measures that have been adopted and discuss whether Law should foster healthy diets. Our purpose is to examine the threats of falling into a paternalistic attitude when devising any regulatory intervention aimed at promoting a healthier lifestyle.

This essay addresses a highly topical subject of increasing interest in Western legal mandamuses today, as focused on debating the role to be played by judges within the democratic system. This is how the problem po sed to Constitutional Law and Political Science by the socalled countermajority objection of the Judiciary, essentially based on the fact that the judges, by not being popularly elected but rather in a very mediate manner , should not, in exercising constitutional control, become the censors of acts and omissions of the other State powers. Against this stance widely spread among academic centers in the United States, nine arguments are submitted, all leading to either neutralize or overcome this objection, and among which those of deep republican rooted politics intertwine with others closer to constitutionaltechnique questions. ; En este ensayo se aborda un tema de creciente interés y actualidad en los ordenamientos jurí­dicos de Occidente, centrado en la discusión acerca del papel que deben cumplir los jueces dentro del sistema democrá¡tico. Así, se considera el problema planteado al Derecho Constitucional y a la Ciencia Polí­tica por la denominada objeción contramayoritaria del Poder Judicial, la cual bá¡sicamente se funda en el hecho de que los jueces, al no ser elegidos por el pueblo sino de un modo muy mediato no deberí­an convertirse, al ejercer el control de constitucionalidad, en censores de los actos y omisiones de los otros poderes del Estado. Contra esta posición, muy difundida en los centros académicos estadounidenses, se presentan nueve argumentos tendientes a neutralizar o superar dicha objeción, entre los que se entrelazan aquellos de profunda raigambre polí­tica republicana, con otros más cercanos a cuestiones de técnica constitucional.

This essay addresses a highly topical subject of increasing interest in Western legal mandamuses today, as focused on debating the role to be played by judges within the democratic system. This is how the problem po sed to Constitutional Law and Political Science by the socalled countermajority objection of the Judiciary, essentially based on the fact that the judges, by not being popularly elected but rather in a very mediate manner , should not, in exercising constitutional control, become the censors of acts and omissions of the other State powers. Against this stance widely spread among academic centers in the United States, nine arguments are submitted, all leading to either neutralize or overcome this objection, and among which those of deep republican rooted politics intertwine with others closer to constitutionaltechnique questions. ; En este ensayo se aborda un tema de creciente interés y actualidad en los ordenamientos jurí­dicos de Occidente, centrado en la discusión acerca del papel que deben cumplir los jueces dentro del sistema democrá¡tico. Así, se considera el problema planteado al Derecho Constitucional y a la Ciencia Polí­tica por la denominada objeción contramayoritaria del Poder Judicial, la cual bá¡sicamente se funda en el hecho de que los jueces, al no ser elegidos por el pueblo sino de un modo muy mediato no deberí­an convertirse, al ejercer el control de constitucionalidad, en censores de los actos y omisiones de los otros poderes del Estado. Contra esta posición, muy difundida en los centros académicos estadounidenses, se presentan nueve argumentos tendientes a neutralizar o superar dicha objeción, entre los que se entrelazan aquellos de profunda raigambre polí­tica republicana, con otros más cercanos a cuestiones de técnica constitucional.

Que los españoles no saben defenderse en una conversación cotidiana en inglés no es una aseveración de carácter novedosa, pero sí de tratamiento urgente. mientras que los últimos datos indican que el inglés es el idioma más hablado en la unión europea en su conjunto, y que se considera lengua franca (Crystal, 2003), menos del 30% de la población española se muestra capaz de poder comunicarse en dicho idioma (Comisión Europea 2005; 2006). Esta situación puede poner en peligro, entre otros aspectos, la cohesión social europea ante un claro desequilibrio de las oportunidades de movilidad laboral y estudiantil. este artículo aborda esta problemática y analiza los principales factores que conducen al éxito del aprendizaje del inglés, agrupándolos en las categorías lingüística, educativa, social y mediática. Ante la ausencia de estudios empíricos, se han empleado informes de organismos oficiales, literatura científica y observación profesional para basar los argumentos. si bien no se pueden ofrecer conclusiones definitivas, se describen los factores educativos y mediáticos como importantes influyentes en el éxito del aprendizaje del idioma. ; The fact that the Spanish cannot hold an everyday conversation in English comes as no surprise, but it remains a matter for urgent redress. Although recent research shows that English is the most widely spoken language in the European Union as a whole, and that it is considered a lingua franca (Crystal, 2003), less than 30% of the Spanish population are able to communicate in said language (European Commission 2005; 2006). This situation may negatively affect the EU 's consolidation process since there is a clear imbalance in the opportunities for student and work mobility. This article tackles this issue and analyses the factors that contribute towards success in learning English, through grouping these factors into those that are linguistic, educational, social, and media-based. In the absence of empirical studies, official reports, scientific literature and professional observation are drawn upon to develop and sustain the argumentation. Although definite conclusions cannot be reached, educational and media factors have been identified as strong influences on foreign language success.

Que los españoles no saben defenderse en una conversación cotidiana en inglés no es una aseveración de carácter novedosa, pero sí de tratamiento urgente. Mientras que los últimos datos indican que el inglés es el idioma más hablado en la Unión Europea en su conjunto, y que se considera lengua franca (Crystal, 2003), menos del 30% de la población española se muestra capaz de poder comunicarse en dicho idioma (Comisión Europea 2005; 2006). Esta situación puede poner en peligro, entre otros aspectos, la cohesión social europea ante un claro desequilibrio de las oportunidades de movilidad laboral y estudiantil. Este artículo aborda esta problemática y analiza los principales factores que conducen al éxito del aprendizaje del inglés, agrupándolos en las categorías lingüística, educativa, social y mediática. Ante la ausencia de estudios empíricos, se han empleado informes de organismos oficiales, literatura científica y observación profesional para basar los argumentos. Si bien no se pueden ofrecer conclusiones definitivas, se describen los factores educativos y mediáticos como importantes influyentes en el éxito del aprendizaje del idioma. ; The fact that the Spanish cannot hold an everyday conversation in English comes as no surprise, but it remains a matter for urgent redress. Although recent research shows that English is the most widely spoken language in the European Union as a whole, and that it is considered a lingua franca (Crystal, 2003), less than 30% of the Spanish population are able to communicate in said language (European Commission 2005; 2006). This situation may negatively affect the EU's consolidation process since there is a clear imbalance in the opportunities for student and work mobility. This article tackles this issue and analyses the factors that contribute towards success in learning English, through grouping these factors into those that are linguistic, educational, social, and media-based. In the absence of empirical studies, official reports, scientific literature and professional observation are drawn upon to develop and sustain the argumentation. Although definite conclusions cannot be reached, educational and media factors have been identified as strong influences on foreign language success.

<p>Studies the impact response of flat Titanium alloy plate against spherical projectile for damage analysis of aero engine components using experimental and finite element techniques. Compressed gas gun has been used to impart speed to spherical projectile at various impact velocities for damage studies. Crater dimensions (diameter and depth) obtained due to impact have been compared with finite element results using commercially available explicit finite element method code LS-DYNA. Strain hardening, high strain rate and thermal softening effect along with damage parameters have been considered using modified Johnson-Cook material model of LS-DYNA. Metallographic analysis has been performed on the indented specimen. This analysis is useful to study failure analysis of gas turbine engine components subjected to domestic object damage of gas turbine engine. </p><p> </p>

Nowadays, in many countries wind energy is responsible for a significant part of the electricity generation. For this reason, Transmission System Operators (TSOs) are now demanding the wind power plants (WPPs) to contribute with ancillary services such as frequency support. To this end, WPPs must be able to temporally increase the active power delivered into the grid to compensate consume and demand imbalances. This implies that WPPs now work below their maximum capacity to keep some power reserve to be able to inject extra power into the grid when needed. This reserve depends on the available wind power, which is directly connected with the wind speed faced by each turbine within the WPP. However, wind speed is negative affected by the wakes caused by the upstream turbines. This paper proposes a control algorithm to distribute the power contribution of each turbine seeking to minimize the wake effects and thus maximize the power reserve. The proposed algorithm is evaluated by simulations for the case of a WPP of 12 wind turbines. ; This work has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grant agreement No 675318 (INCITE).

Multi-objective optimization (MOO) is widely used in engineering systems design and planning. The solution of a MOO problem leads to a set of efficient points (Pareto set) from which decision-makers should identify the one that best fits their preferences. Generating this set requires large computational efforts, and the post-optimal analysis of the solutions becomes difficult as the number of objectives increases. This work introduces an approach based on the Analytic Hierarchy Process (AHP) to overcome these limitations. Through the definition of an aggregated objective function calculated using the AHP algorithm, a single-objective model is constructed that provides a unique Pareto solution of the original MOO model. The AHP is combined with a mixed-integer non-linear programming (MINLP) formulation that simplifies its application and is particularly suited to deal with many objectives (like those arising in sustainable engineering problems). The capabilities of the approach are demonstrated through a case study addressing the sustainable sugar/ethanol supply chain design problem. ; The authors wish to acknowledge support from the CONICET, Argentina (project PIP 00785 and doctoral scholarship), and the Spanish Government (ENE2015-64117-C5-3-R, CTQ2016-77968-C3).

Nowadays, wind power plants (WPPs) should be able to dynamically change their power output to meet the power demanded by the transmission system operators. When the wind power generation exceeds the power demand, the WPP works in de-loading operation keeping some power reserve to be delivered into the grid to balance the frequency drop. This paper proposes to cast a model predictive control strategy as a multi-objective optimization problem which regulates the power set-points among the turbines in order to track the power demand profile, to maximize the power reserve, as well as to minimize the power losses in the inter-arrays connecting the wind turbines within the wind farm collection grid. The performance of the proposed control approach was evaluated for a wind farm of 12 turbines using a wind farm simulator to model the dynamic behavior of the wake propagation through the wind farm. ; This work has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sk lodowska-Curie grant agreement No 675318 (INCITE). ; Peer reviewed