Applied Mechanics and Materials Vol. 372

Abstract: CuIn_0.8Ga_0.2Se₂ thin film is grown at room temperature by RF sputtering using high quality of CuIn_0.8Ga_0.2Se₂ single phase target. A (112) diffraction peak is dominant with no secondary phases such as selenide materials in the X-ray diffraction pattern. A flat and homogeneous surface can be obtained in the sample.

Abstract: If the optical collector surfaces in concentrator photovoltaic (CPV) systems are soiled, a significant proportion of sunlight is scattered and definitively lost because the scattered rays cannot be focused onto the solar cell. In this study, we studied the influence of soiling on poly-methyl methacrylate (PMMA) substrates with and without super-hydrophilicity anti-soiling layer. After 5 months, the reduction rate of transmittance for the sample without anti-soiling coat was 7.1%. In contrast, that for the sample with anti-soiling coat could be suppressed to 4.2%. Moreover, the relationship between wind speed and accumulation of dust was discussed.

Abstract: CuInSe₂ thin films were prepared under vacuum by conventional evaporation method .The films were deposited at different film thickness (188-577nm) .XRD of as-prepared powder indicated that CuInSe₂ has tetragonal poly crystalline structure with(122) preferred orientation, while XRD of the as-deposited films were of a mixed amorphous- microcrystalline nature. The variation of the calculated lattice parameters at different film thickness were showed. The electrical properties of CuInSe₂ thin films were studied at different film thickness. The dark conductivity of the films was measured as a function of temperature. Two regions were obtained corresponding to two activation energy. The activation energy decreases with increasing the film thickness.

Abstract: This paper reports the improvement of open circuit voltage stability of solar cell using InN based quantum dot in the active layer of the device structure. We have analyzed theoretically the temperature dependence of the open circuit voltage of the solar cell to investigate its fluctuation using Ge and InN based quantum dot in the active layer of the solar cell. Numerical results obtained are compared. The comparison results reveal that the open circuit voltage has been reduced a little bit but the fluctuation of terminal voltage has been reduced significantly by using InN quantum dot in the active layer of the device structure. Therefore InN is proved to be an excellent material to fabricate solar cell to provide higher stability in the open circuit voltage of the solar cell in very near future.

Abstract: Pure Water is the important source for living creature survival which enriches their life. Solar stills is the best method to obtain the pure water from the sea water. Sea water available free from cost. Free energy is utilized to drive the solar still hence the non renewable energy is conserved, free from risk, pollution, damage, occupies lesser space, installing and maintain cost of the solar still is less. The basin material is chosen according to the thermal conductivity and lower cost analyses. An experimental and theoretical study have been done on solar still to optimize the design by examining the design, operational and climatic parameter on its performance. Single basin solar stills with basin volume of 500 mm × 500 mm ×200 mm have been fabricated by using saint gobian glass material. A 5 mm thick glass cover was used as a transparent material. This glass cover with an inclination of 13° is fixed to the vertical wall of the still. The whole assembly was air tight made with help of aluminium foil gasket and clips. This work mainly concentrates on the solar radiation, cover title angle, depth of the water.

Abstract: Modelling of an ill-defined system such as the wastewater treatment plant is quite tedious and difficult. However, successful and optimal operation of the system relied upon a suitable model. Most of the available developed models were applied to industrial wastewater treatment plants. This paper presents adaptive neuro fuzzy inference system (ANFIS) model for carbon removal in the Bunu domestic wastewater treatment plant in Kuala Lumpur, Malaysia. For comparison feed-forward neural network (FFNN) was used. Simulation results revealed that ANFIS model is slightly better than the FFNN model, thus proving that the model is a reliable and valuable tool for the wastewater treatment plant.

Abstract: This article is based on ADAMS software platform to solve working space of the 4-DOF parallel mechanism. Design a kind of 4-DOF parallel mechanism and establish virtual prototype on ADAMS software platform. Then through enumeration three branched chain parameters combination, even without the premise of kinematics positive solution, we can solve it working space using the forward solving method and get the branched chain parameter with the reference point position corresponding numerical relations. It greatly simplifies the solution of the working space of parallel mechanism, is more advantageous to parameter optimization and trajectory planning of parallel mechanism.

Abstract: As switched reluctance machines (SRM) generally offer a simple and robust design, they are very suitable for electromechanical actuation systems which need to be actuated by fault tolerant drives. This paper investigates dual-channel, dual-redundancy, lacking phase schemes of SRM guaranteeing fault tolerance and the corresponding control systems in detail are compared to point out the advantages and disadvantages of them., a new lacking phase scheme for 12/8 SRM is proposed and the finite element model based on field-circuit coupling is established, results indicate that this scheme have superior fault tolerant performance and suit tasks in electro-mechanical actuation system of aerospace environments.

Abstract: The natural characteristics of fluid conveying pipe with its ends under different supporting conditions were investigated. The expression of vertical vibration mode-function of pipe beam was derived from the boundary conditions of similarly supported beam. The effect of different supporting elastic coefficient, fluid pressure, flowrate, and axial force of pipe section on its natural characteristics was calculated and analyzed based on the eigenequation of motion. The numerical computation results showed that its natural frequency was proportional to elastic supporting coefficient and axially pressed force of pipe section, but was proportional conversely to fluid flowrate, fluid pressure and axially sectional drawn force of pipe. The natural frequency of different modes can be coupled with each other, the primarily mode and secondly mode would change either. In order to improve the natural frequency of fluid conveying pipe, the elastically constrained coefficients should be extended and the axially pressed force of pipe section should be avoided.

Abstract: This paper deals with structural analysis of bus superstructure undergoes rollover event. Bus superstructure with varying beam profile size will undergo rollover simulations analysis. The purpose of this work is to analyze structural response of bus superstructure in terms of deformation, stress and strain under several loadings and constraining conditions. These rollover simulations were run according to United Nation Economic Commission of Europe Regulation 66 (UNECE R66). Validation procedure using simple box modeled undergoes rollover have been done to ensure the results are synchronized with real problem. An interaction with bus coach builder allows author acquired accurate bus superstructure dimensions before designing the mathematical model in finite element analysis software. Three full-scale bus superstructures mathematical model with difference cant-rail horizontal roof beam profile size was developed and the deformation of superstructure during and after rollover testing had been study. Analyses suggested that one of the contributing factors that lead to the failure of bus having rollover accident is cant-rail and roof structure profile size.