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Objective: To investigate the association between testosterone deficiency and depressive and/or anxiety symptoms.

Solar flat plate collectors are commonly used to transform solar energy into thermal one by heating a heat transfer fluid (HTF). The available thermal energy to the user is characterized by a certain thermal capacity and a certain temperature level. Comparing to the case of a single collector, when a higher thermal capacity is required in the user process, more collectors should be coupled in parallel, so that the HTF mass flow rate is increased, exiting the solar collector at the same temperature. Another case may be encountered when the user process requires the same mass flow rate of HTF, but at a higher temperature. In this last case, a series connection is considered. The aim of the present paper is to compare these cases and to build a solar panel map that could be used to choose the best arrangements for a specific user need. A study is performed regarding the map dynamics with respect to HTF consumption to the user for three storage tank capacities of 100L, 200L and 300L respectively. The results reveal a recommendation regarding collectors coupling function on user needs.

Storage processes are usually integrated in solar energy systems applications due to daily variation of this energy source availability. Among different thermal storage solutions, phase change materials (PCM) lately became more extensively used covering a wide range of operating temperatures. In this regard, a numerical simulation of a PCM melting process is performed under ANSYS CFD environment. A particular configuration is considered consisting in a 2m length annular tube having a 5.48 cm external diameter. The tube is filled with paraffin chosen as PCM. A concentric interior tube of 2.54 cm diameter is used for transporting the heat transfer fluid (HTF) from the solar collector. Heat is transferred through the 1 mm thick pipe wall to the PCM placed all around the HTF tube. The numerical results reveal the melting process of the PCM at different instances and tube sections. The time variation of the PCM liquid fraction is emphasized. The results describe the dynamic behavior of a PCM melting process and might be further integrated in any solar power plant storage charging process simulation.

This paper describes the development of a small-scale solar simulator for research and educational purposes. The main goal is to provide a uniform and stable distribution of irradiation from a set of four floodlight halogen lamps, over a targeted area of 40x40 cm2. The floodlights are placed perpendicularly to each other, on the top end of a light tube. Two types of halogen lamps were characterised and the total irradiation of the solar simulator was measured over a 5x5 grid. The results showed that the two arrangements of lamps are able to achieve a level of 1000 W/m2 on the 40x40 cm2 targeted area, but the non-uniformity is unsatisfactory. In order to reach a non-uniformity level of 10% using the proposed lamps arrangements, the targeted area should be reduced to 31x31 cm2.

A solar driven cooling system consisting of a single effect H2O-LiBr absorbtion cooling module (ACS), a parabolic trough collector (PTC), and a storage tank (ST) module is analyzed during one full day operation. The pressurized water is used to transfer heat from PTC to ST and to feed the ACS desorber. The system is constrained to operate at the maximum ACS exergetic efficiency, under a time dependent cooling load computed on 15 July for a one storey house located near Bucharest, Romania. To set up the solar assembly, two commercial PTCs were selected, namely PT1-IST and PTC 1800 Solitem, and a single unit ST was initially considered. The mathematical model, relying on the energy balance equations, was coded under Engineering Equation Solver (EES) environment. The solar data were obtained from the Meteonorm database. The numerical simulations proved that the system cannot cover the imposed cooling load all day long, due to the large variation of water temperature inside the ST. By splitting the ST into two units, the results revealed that the PT1-IST collector only drives the ACS between 9 am and 4:30 pm, while the PTC 1800 one covers the entire cooling period (9 am-6 pm) for optimum ST capacities of 90 kg/90 kg and 90 kg/140 kg, respectively. [ABSTRACT FROM AUTHOR]

Four decades ago, A. Bandura defined self-efficacy as people's confidence in their ability to produce the desired levels of performance, levels which exert a certain influence upon the events shaping their lives. Self-efficacy - as a cognitive process - generates motivation, options, emotions, ideas and behaviours. Th e person not only assesses one's own abilities in the light of past success or failure, but chooses certain tasks, doses one's eff ort and monitors one's eff ects according to past experience. Th is study aims to identify the diff erences between levels of self-efficacy according to gender, as well as to correlate self-efficacy with personality factors (sensation-seeking, sociability, and activity). [ABSTRACT FROM AUTHOR]

Along with the passage of time, parents have manifested a different attitude towards their children, trying to offer them everything they wanted in what concerns the toys. Therefore, the toy market is constantly expending, and the tough competition leads to the quality improvement of the toys and enforces certain standards on the market. The originality and topicality of the theme consist in the change in the toy consumers' and users' preferences which required greater attention to be paid to the influence manifested by the marketing environment on this market. The case study identifies the occurred problems and the toy influence factors by an analysis over the marketing environment components, i.e.: marketing internal environment, micro-environment and macro-environment. The study ends with the recommendation of several solutions for the improvement of the current situation. [ABSTRACT FROM AUTHOR]

This paper aims to address the issue of drug use and the favoring of this phenomenon, because the trend in the world, especially among young people, begin to converge in recent decades, and the effects of drug use are felt both from the individual, but especially by the society. Thus, Romania is also part of this trend, and it has the tendency to increase the number of addicts and perhaps which is more alarmingly, the decrease in age at onset of drug use. [ABSTRACT FROM AUTHOR]

A thermodynamic model for accurately predicting the overall efficiency and power output of a solar assembly using a Stirling engine is presented. It is based on the application of the First Law of Thermodynamics for Processes with Finite Speed and uses the Direct Method. The proposed model could also be used to better design receivers that concentrate the solar radiation and to properly size the receiver cavity for a dish solar concentrator. Examples of the optimization of the performance of Stirling engines are also included, as is a comparison of the optimization results with actual performance data from operating solar Stirling engines. [ABSTRACT FROM AUTHOR]