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Abstract: A computer vision system tries to mimic our primary sense (sight) in order to gather information without the need for physical interaction, in fact such systems are able to grade automatically, and extract useful information with a degree of sensitivity closer to that of a human, reducing considerably the margin of error. By performing digital image processing, defined as the acquisition and processing of visual information by computer, computer vision systems allow analyzing image data for specific applications in order to determine how images can be used to extract the required information. Among the most important features for accurate classification and sorting of products it can be mentioned the shape. The shape of objects or regions of interest are important features used for content representation, and require good segmentation to detect objects or regions. Basically, shape characterization is of two types: boundary-based and regionbased. Boundary-based shape features include rectilinear shapes, polygonal approximation, finite element models, and Fourier-based shape descriptors. Region-based features include statistical moments and grid-based approaches. Object shape detection using a technique based on Hough Transform for further segmentation is presented on this paper. [Copyright &y& Elsevier]

• In this research work, three different types of CIGSe-based thin film solar cells (TFSCs) such as CISe, CIGSe, and CIGSe bilayer TFSCs are simulated through SCAPS software. • Comparative study on the solar cell parameters of these CI(G)Se TFSCs and finding the best conditions for achieving high device performance are the novel approaches of this research work. • The device's performance is optimized to get maximum efficiency by analyzing the material properties, such as thickness and carrier concentrations of CI(G)Se, CdS, ZnO, and ZnO:Al materials used in CIGSe-based thin film solar cells. • The experimentally obtained parameters of CIGSe thin films deposited by the hybrid deposition method and CdS thin films deposited by the chemical bath deposition method are also analyzed through this simulation and obtained more than 20% efficiency, showing potential to get high device performance. • Finally, the influence of defects (present in the absorber layer, buffer layer, and their interface), work temperatures, and parasitic resistances on the solar cell parameters are investigated. • Understanding the results obtained from the theoretical modeling can help in designing the experimental work, saving material resources and research time. The copper indium selenium/copper indium gallium selenium (CI(G)Se)-based thin film solar cells (TFSCs) have been fascinating in the photovoltaic market due to their potential to attain high efficiency of solar cells and modules at relatively little cost. This research work introduces the simulation of the CI(G)Se TFSCs through SCAPS software. Some parameters like thickness, bandgap, and carrier concentration of semiconducting materials used in the CI(G)Se TFSCs were optimized to get the solar cell efficiency as high as possible. The optimized efficiencies for CISe, CIGSe, and CIGSe bilayer TFSCs were 22.81, 27.32, and 27.99%, respectively. It is seen from the results that the device's performance using two absorber layers in CI(G)Se TFSCs was comparatively higher than using a single absorber layer. This outcome is mainly due to the better absorption of photons in CI(G)Se TFSCs containing two absorber layers. The SCAPS software also analyzed the experimentally obtained parameters of CI(G)Se and CdS thin films and noticed more than 20% efficiency, showing potential parameters to use in commercial applications. The effect of defects found in the CI(G)Se absorber layer, CdS buffer layer, and CdS/CI(G)Se interface on the solar cell parameters are primarily studied here. It is observed that the increasing defects in the CI(G)Se TFSCs could impact negatively the device's performance by recombining the generated charge carriers. Better results were found for CI(G)Se TFSCs at a lower work temperature (by reducing the saturation current, and at a smaller series resistance value as well as a larger shunt resistance value (by reducing the alternative paths for generated charge carriers). Therefore, understanding these results could provide complete information on the optimization process that can serve as a guide to achieve highly efficient electronic devices experimentally. [ABSTRACT FROM AUTHOR]

This paper proposes a mathematical model for a solar Dish/Stirling system. Firstly, it is presented a methodology to calculate the appropriate angles and characterize the solar tracking control system for the city of Itajubá-MG/Brazil, in order to maximize the heat flow on the cavity of the receiver. Secondly, it was developed an algorithm for sizing and to determine the effects of opto-geometric parameters on the overall efficiency of the Dish/Stirling system. The model allows defining different configurations and geometric distances between the concentrator and the receiver, in order to obtain the desired heat in the receiver cavity. Finally, it is carried out a thermal balance for the evaluation of the maximum efficiency and overall efficiency of the system. The results obtained for a concentrator with a diameter of 10.5 [m] and solar irradiation of 1000 W/m 2 are: theoretical maximum working temperature in the receiver surface of 1596 K and a maximum thermal efficiency of 68%. It is observed that for collectors between 10 and 20 m of diameter, the overall efficiency variation is not significant (23–25%), since the variation of the temperature of the receiver and the thermal losses in the cavity are minimal for the evaluated conditions. [ABSTRACT FROM AUTHOR]

• For multi-product systems, allocation of resources and residues is difficult. • Thermoeconomics is an ideal tool to carry out Life Cycle Assessment studies. • Environmental load allocated by traditional and thermoeconomic methods. • Advantages and disadvantages of allocation methods are presented in a case study. When analysing multi-product systems, the allocation of resources and waste in a Life Cycle Assessment presents a difficulty. This can be solved through thermoeconomic approaches. Thus, the objective of the present work was to carry out a comparative analysis between traditional methods, recommended by ISO 14000, and thermoeconomic methods in the Life Cycle Assessment of a cogeneration system composed of a gas microturbine and lithium bromide–water absorption systems. First, the system's total emissions were calculated, and then the allocation of resources was carried out. This allocation was achieved in three ways: traditional allocation, thermoeconomic allocation, and allocation through exergoenvironmental analysis. To carry out the last two allocations, the exergetic costs were calculated considering the physical structure and the productive structure of the production flows (using four different exergy breakdown models,). And with the result of the exergetic costs, the environmental impacts (environmental costs) were calculated through the thermoeconomic allocation and the exergoenvironmental analysis. The environmental impacts (environmental costs) found with allocations that use thermoeconomics were compared with those obtained by the Life Cycle Assessment with the traditional allocation (energetic and exergetic). Thus, it was found that the results obtained by the energy allocation and the allocation that uses the thermoeconomic model of total exergy have the highest environmental impact over the cold production. It was also found that there is no difference between using an exergetic allocation or thermoeconomic allocation if the system does not have many dissipative components, such as valves, and there is no need to know the influence of the components on the final environmental impact since both perform the same calculations with very few modifications. It was concluded that, when performing a thermoeconomic analysis on a system with valves, one can use any of the models studied, depending on how detailed one wants the results of their environmental impact to be. On the other hand, if the system does not contain many dissipative elements or one does not need a detailed result, one should just make the traditional exergy allocation. Moreover, if it is necessary to know which component has the greatest environmental impact, the exergoenvironmental analysis should be used. Thus, this work contributes to a compilation of all the thermodynamic models used to date, and how they can be applied in a Life Cycle Assessment to generate more detailed results. [ABSTRACT FROM AUTHOR]