Power electronics (PE) plays a major role in electrical devices and systems, namely in electromechanical drives, in motor and generator controllers, and in power grids, including high-voltage DC (HVDC) power transmission. PE is also used in devices for the protection against grid disturbances, like voltage sags or power breakdowns. To cope with these disturbances, back-up energy storage devices are used, like uninterruptible power supplies (UPS) and flywheels. Some of these devices may use superconductivity. Commercial PE semiconductor devices (power diodes, power MOSFETs, IGBTs, power Darlington transistors and others) are rarely (or never) experimented for cryogenic temperatures, even when designed for military applications. This means that its integration with HTS power devices is usually done in the hot environment, raising several implementation restrictions. These reasons led to the natural desire of characterising PE under extreme conditions, e. g. at liquid nitrogen temperatures, for use in HTS devices. Some researchers expect that cryogenic temperatures may increase power electronics' performance when compared with room-temperature operation, namely reducing conduction losses and switching time. Also the overall system efficiency may increase due to improved properties of semiconductor materials at low temperatures, reduced losses, and removal of dissipation elements. In this work, steady state operation of commercial PE semiconductors and devices were investigated at liquid nitrogen and room temperatures. Performances in cryogenic and room temperatures are compared. Results help to decide which environment is to be used for different power HTS applications

The driving force behind the work herein presented is the importance of budgeting in a competitive market. The problem at hands is the creation of a budgeting methodology for reverse engineering applications, involving laser scanning, that has the ability to generate budgets for different customer accuracy requirements and for parts of different morphologic characteristics, such as: shape, dimension and/or detail complexity. A breakup approach was used to implement the methodology: the reverse engineering process was broken in nine basic identified steps and elementary sources of cost were defined at the different reverse engineering stages as well. Particular budgeting methodologies for each step of the process were created. The obtained results so far point to the possibility of creating a complete budgeting system based on the proposed methodology. © 2008 Taylor & Francis Group.

Thin films of molybdenum-doped indium oxide (IMO) were prepared by a 3-source, cylindrical radio-frequency magnetron sputtering at room temperature. The films were post-annealed and were characterized by their structural (X-ray diffraction) and optical (UV-VIS-NIR spectrophotometer) properties. The films were studied as a function of oxygen volume percentage (O2 vol.%) ranging from 3.5 to 17.5. The structural studies revealed that the as-deposited amorphous films become crystalline on annealing. In most cases, the (222) reflection emerged as high intensive peak. The poor visible transmittance of the films as-deposited without oxygen was increased from ∼ 12% to over 80% on introducing oxygen (3.5 O2 vol.%). For the films annealed in open air, the average visible transmittance in the wavelength ranging 400-800 nm was varied between 77 and 84%. The films annealed at high temperatures (> 300 °C) decreased the transmittance to as low as < 1%. The optical band gap of the as-deposited films increased from the range 3.83-3.90 to 3.85-3.98 eV on annealing at different conditions. © 2007 Elsevier B.V. All rights reserved.

This study describes the characterisation of whey protein hydrolysates obtained from tryptic hydrolysis to assess their application as ingredients with angiotensin-converting-enzyme (ACE) inhibitory action. The levels of a-lactalbumin (alpha-la) and P-lactoglobulin (beta-lg) remaining after hydrolysis were quantified. Peptides were separated by RP-HPLC, and Ala-Leu-Pro-Met-His-Ile-Arg (ALPMHIR), the most potent beta-lg-derived ACE-inhibitory peptide was monitored. A correlation curve was established for the production of this peptide as a function of hydrolysis time. Heat-induced gelation of hydrolysates was studied by small-deformation rheology. The gelation times and the strength of the final gels were highly dependent on the degree of hydrolysis. Smaller peptides liberated by hydrolysis contributed to the inability of whey protein hydrolysates to gel. (c) 2006 Elsevier Ltd. All rights reserved.

Algunos de los fenómenos donde el concepto de “globalización” es aplicado incluyen la internacionalización de los mercados, la globalización de la cultura, el dominio político hegemónico del mundo por algunos estados poderosos, o grupos de estados, el poder creciente de organismos supranacionales, y el desarrollo de una división global de trabajo. De acuerdo con Radice, la globalización é generalmente definida como “un proceso a través de lo cual una proporción creciente de transacciones económicas, sociales e culturales ocurre directamente o indirectamente entre partners de países distintos” (Radice, 2004: 154). Un ponto de partida para entender la división global del trabajo debe ser la investigación de los modos como las empresas se reestructuran, una vez que son los actores-llave en la decisión sobre que trabajo debe ser encontrado y donde. Las “cadenas de valor” descriven cada etapa en el proceso productivo de un producto o un servicio final. La palabra “valor” en la frase “cadena de valor” dice respecto al valor añadido. Cada etapa en la cadena de valor implica recibir inputs, procesarlos, y entonces pasarlos a la unidad siguiente en la cadena, con el valor que está sendo adicionado no proceso. As unidades separadas da cadena de valor pueden estar dentro da misma empresa (in-house) o en distintas empresas (outsourced). Similarmente pueden estar en un mismo local, o en otra localización. La normalización de muchos procesos del negocio, combinada con la digitalización da información y el desarrollo de redes de telecomunicaciones de elevada capacidad ha tornado posible el trabajo tele-mediado, pudiendo este ser externalizado y/o re-localizado, conduciendo à introducción de una división de trabajo internacional no trabajo de procesamiento de información. Esta comunicación presentará algunos resultados derivados do proyecto europeo WORKS, donde son estudiados casos portugueses de empresas que justamente se integran en

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