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El diagrama de casos de uso describe las interacciones entre un usuario y una pieza de software. Se han realizado algunos trabajos que buscan la generación automática o semiautomática del diagrama de casos de uso desde descripciones en lenguajes naturales o controlados. Sin embargo, estos esfuerzos no han sido suficientes porque algunos parten de un lenguaje controlado orientado a la solución, la cual no existe en las etapas iniciales del ciclo de vida del software; otros trabajos requieren una alta intervención del analista para la generación del diagrama, lo cual es altamente inconveniente si se trata de automatizar el proceso; finalmente, no se identifican todos los elementos del diagrama de casos de uso, en particular las relaciones especiales (>, > e >). En este artículo se define un método basado en reglas heurísticas que permite identificar los actores, los casos de uso y las relaciones especiales del diagrama de casos de uso, tomando como punto de partida una representación en lenguaje controlado del dominio del problema: los denominados esquemas preconceptuales. Además, se realiza la implementación de estas heurísticas en la herramienta metaCASE AToM3 y se ejemplifica con un caso de estudio

The electrochemical formation of Dy–Ni alloys was investigated in molten CaCl2–DyCl3 (1.0 mol%) at 1123 K. Cyclic voltammetry indicated the formation of Dy–Ni alloys at more negative than 1.0 V vs. Ca2+/Ca. Higher cathodic currents were observed from approximately 0.6 V, which indicated the formation of Dy–Ni alloys having higher Dy concentration. An open-circuit potentiometry was carried out with Mo and Ni electrodes before and after the addition of DyCl3. After the potentiostatic electrolysis of Mo electrode at −0.50 V for 30 s in molten CaCl2–DyCl3, only one potential plateau appeared at 0.33 V, which was interpreted as the equilibrium potential of Dy3+/Dy. In contrast, four potential plateaus were observed at 0.49, 0.62, 0.87, and 1.04 V for Ni electrode after the potentiostatic electrolysis at 0.25 V for 15 min. According to energy-dispersive X-ray spectroscopy and X-ray diffraction of the electrolyzed samples, the four potential plateaus correspond to the two-phase coexisting states of (DyNi + DyNi2), (DyNi2 + DyNi3), (DyNi3 + DyNi5), and (DyNi5 + Ni). Standard Gibbs energies of formation were calculated for Dy–Ni alloys.

Electric Vehicles have several potential advantages over traditional internal combustion engine vehicles. They promise zero emission and efficiency. State of charge of a battery is considered as one of the important parameters of Lead acid battery. Study has been done and identified that temperature is a main factor that affects the state of charge of the battery and some measures are to be taken to improve its performance. Unscented kalman filter plays a vital role in estimating the real state of charge of a lead acid battery. Testing of lead acid battery has been done in real-time. Unscented kalman filter code is implemented in MATLAB environment and the state of charge has been estimated for the degrading battery.

A high pressure/high temperature reactor was used in semi­continuous mode for hydroprocessing of Cracked Vegetable Oil (CVO). Therefore, hydrogen with a partial pressure of 50 bar was conveyed continuously through the pilot plant. The reaction temperature was 350 °C. This temperature was hold for 3 h in each experiment. CVO was provided in the reactor for treatment with a molybdenum catalyst with traces of heavy metals in a ratio of 1 wt.­% corresponding to the mass of CVO in the reactor at the beginning of the test. Deoxygenation (DO) reactions were found in all experiments and Hydrogenated Cracked Vegetable Oil (HCVO) was obtained. Acid number and calorific value measurement as well as selectively gas chromatography/mass spectrometry (GCMS) was performed for proving DO. CVO used in this study was made from rapeseed oil. The aim of the project is the transfer of those findings to CVO which is based on used frying oil. Conventional raw materials suffer on a lack of sustainability and high cost. CVO removes these drawbacks and provides a high quality product with high energy density at the same time. Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1034-1037

Solar cells require effective protection against environmental influences so that they can convert sunlight into energy for a long time. Backsheets provide long-term protection for solar cells against mechanical and chemical influences and the effects of the weather at the backside of the solar cells. State of the art at the frontside is the usage of glass to ensure protection particularly against water vapour. For thin film PV technologies, flexibility is a major advantage compared to crystalline solar-cells. As a result new frontsheet materials, which are flexible, are in the focus. But not only flexibility is a very important property, also WVTR (water vapour transmission rate), transparency, YI (yellowing index) as well as costs have to be kept in mind. For CIGS photovoltaic devices, barrier materials with WVTR of at least 10-4 g/m2d are necessary to provide lifetime of more than 20 years. Aim of the presented work is to introduce new transparent barrier frontsheets for PV applications. 27th European Photovoltaic Solar Energy Conference and Exhibition; 2985-2987

In this work, we conducted a study that is to bleach wastewater model solutions loaded with dyes of indigo and sulfur black, while using and optimizing the process of hybridized treatment of textile effluents by torque of coagulation-ultrafiltration (CO-UF). According to the separate optimization of coagulation processes (optimum dose of the coagulant (lime) and ultrafiltration membrane (hydrodynamic characterization of the membrane based on polysulfone (PSU)), we combined the two methods in order to increase performance fading exploited colored waters. The results of the rate of discoloration separated by the methods of coagulation and ultrafiltration are respectively of the order of 33.55% and 80.36% for the water loaded with indigo and of the order of 25.33% and 60.78% for those charged with the black sulfur. While the results of the bleaching obtained by the hybrid method CO-UF have shown that the bleaching rate was calculated as around 98% for the indigo and of the order of 92% for the black sulfur, obviously very interesting with respect to the coagulation and ultrafiltration used separately. Moroccan Journal of Chemistry, Vol. 4, No 1 (2016)

In the study, the effect rates of independent variables (cutting speed, feed rate, cutting depth and tool nose radius) on the dependent variables (surface roughness) used during turning of C45 manufacturing steel were investigated and optimum cutting parameters were determined. Turning experiments were performed according to the L27 orthogonal (Vertical) array of the response surface method (RSM). As independent variables 3 different cutting speeds (160 m/min, 260 m/min and 360 m/min), feed rate (0.05 mm/rpm, 0.18 mm/rpm and 0.31 mm/rpm), cutting depth (0.1 mm, 0.3 mm and 0.5 mm) and tool nose radius (0.4 mm, 0.8 mm and 1.2 mm) were used. As a result analysis of Variance, the effects of independent variables and the effects of interactions on dependent variables were examined. As a result, it was determined that the most effective independent variable on the dependent variable was the feed rate and tool nose radius, respectively, while the effect of cutting speed and cutting depth was found to be low. It was found that while the feed rate increased, the dependent variable increased and the tool nose radius decreased.

El despacho hidrotérmico determina la relación adecuada entre la generación hidráulica y la generación térmica de tal forma que el costo operativo sea óptimo durante el período de planeamiento, cumpliendo con las restricciones de generación, transmisión y demanda; además, establece el uso racional y eficiente de los recursos energéticos de los sistemas eléctricos de potencia. En muchos casos el problema del despacho hidrotérmico es simplificado para encontrar una solución en un tiempo computacionalmente razonable. Entre las principales simplificaciones se encuentran: linealizar las funciones de costo de las plantas térmicas, eliminar las restricciones de la red de tal forma que el despacho se realice a nodo único y considerar la demanda y el caudal de forma determinística. En este articulo se presenta un método de solución al problema del despacho hidrotérmico mediante las técnicas de punto interior y simulación de Monte Carlo, el modelo propuesto considera las curvas de costo de las plantas térmicas, las restricciones de la red, la incertidumbre en el pronóstico de la demanda y la aleatoriedad en las afluencias lo cual permite obtener distribuciones de probabilidad en las variables de salida del problema (función de costos, potencias generadas, etc).

Distance learning has become the basis for the functioning of the information society. Without it, it is difficult today to imagine the process of education. If, in addition, we will have to deal with education at managerial level should be aware of the rapid depreciation of knowledge. The effectiveness of distance learning can be improved by using learning objects. Learning objects allow for quick adaptation to the changing environment due to space and time. This article will discuss the organization of learning objects in the distance learning systems.