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Abstract The gradual depletion of fossil-fuel-based energy resources and the growing rate of greenhouse gas emission are two of the most significant global concerns in recent years. These concerns have resulted in an increasing demand for the utilization of renewable energy resources. From among all renewable resources, hydropower is the leading contributor to grid-connected electricity in the world. In this article, the hydropower potential in Malaysia, current and future prospects of large and small-scale hydropower development, and issues and challenges related to hydropower development are described. Small hydropower promotion techniques, government initiatives, and the advantages and barriers to small hydropower development are also included. Highlights • Hydropower potential in Malaysia. • Current and future prospects of large and small scale hydropower development. • Issues and challenges related to hydropower development. • Small hydropower promotion techniques, government initiatives and advantages and barriers towards small hydropower development. [ABSTRACT FROM AUTHOR]

Eu 0.65 Sr 0.35 Fe x Mn 1− x O 3 ( x =0.1, 0.3 and 0.5) has been prepared using a standard solid state reaction method. The under-investigation compounds is found to crystallize in a single-phase orthorhombic structure in the P bnm space group (62). The adiabatic polaron electronic transfer was obtained for all samples and the activation energy of x =0.1 sample is equal to 1.013 meV and slightly increase at x =0.3 (1.289 meV) while is doubled for x =0.5 to be 2.1065 meV. The magnetization–temperature dependence measurements of Eu 0.65 Sr 0.35 Fe x Mn 1− x O 3 show the ferromagnetic ordering at low iron concentration x =0.1 and when iron concentration increase to x =0.5 the noncollinear magnetic ordering (the canted antiferromagnetic) is obtained. The magnetic phase transition (paramagnetic-ferromagnetic transition) in the Eu 0.65 Sr 0.35 Fe 0.1 Mn 0.9 O 3 is observed at T c of 150 K. For Eu 0.65 Sr 0.35 Fe 0.5 Mn 0.5 O 3 the multi-magnetic phase transition is observed at T c of 200K and T N of 430 K. The resistivity at low temperature is measured. Theoretical Calculations using Monte Carlo code have been done. The magnetization as function of temperature has been calculated using Monte Carlo simulations for Eu 0.65 Sr 0.35 Fe x Mn 1− x O 3 ( x =0.0, 0.1, 0,2, 0.3, 0.4 and 0.5). Ising model is a suitable model to study the magnetization for our compounds. The internal energy for x =0 is the highest value compared with the other x values which have nearly a ground state value equal to 2.7 J [ABSTRACT FROM AUTHOR]

This paper presents a three-phase hybrid multilevel converter (MLC) topology for photovoltaic (PV) grid-connected system with a new current control scheme. Deadbeat current controller in α-β reference frame is designed in S-domain using derivative feedback to make the actual current to track exactly the reference current. The controller generates α-β reference voltage for inverter with lower power electronic components. The inverter has high quality output voltage which leads to a high quality injected grid current thus eliminates the using of custom and more expensive power filter for the high power rating systems. Besides, MLC switching losses is very low due to most of the power cell switches are operating at nearly fundamental frequency. Some selected simulation results are presented to validate the proposed system and the proposed control scheme. [ABSTRACT FROM AUTHOR]

Abstract: Polymeric films composed of mixture of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) are prepared from casting combined solvent (methylene chloride and methanol in 1:1 ratio) containing 8% weight/volume of both polymers (EC to HPC in 1:3 weight ratio). The structural and optical studies of the films are carried out by X-ray diffraction and UV–vis spectrophotometer. The films are polycrystalline structure with an average grain size from 23.15 to 10.79nm. The possible optical transition in these films is found to be allowed direct transition. The optical band gap energy (E g ) is estimated to be 5.02eV for HPC–EC plain film and then decreases with increasing the filler content reaching to 4.24eV for the film filled with maximum Se80Te14Sn6 content of 1w%. This suggests that Se80Te14Sn6, as filler, is a good choice to control the optical properties of HPC–EC blend film. [Copyright &y& Elsevier]

Cadmium Selenide, CdSe, thin films deposited on different substrate types; FTO/glass,/glass, and ITO/glass substrates were produced by thermal evaporation method in the room temperature. The influence of different types of substrates on the structural, optical and electrical properties of the films was studied by X-ray diffraction and absorption photo spectroscopy respectively. X-ray diffractions revealed that all the CdSe films have a polycrystalline with cubic structure having preferred orientation (111) at 2θ ≈ 25.1°. The optical energy band, E g , values support the fact that the films have semiconductor behavior which can be attributed to the quantum confinement effect. It was observed that the optical properties such as transmittance, reflectance, optical bandgap, and refractive index and some another parameters of CdSe films were strongly affected by types of substrates. The electrical properties were measured at room temperature using two probe methods. • Influence of the substrate on the structural, optical and electrical properties of CdSe thin films. • Swanepoel's involved methods were used to calculating the film thickness and refractive index. • Cauchy's equation used to fitting the refractive index in whole wavelength. • Electrical resistivity for CdSe films were measured in room temperature. [ABSTRACT FROM AUTHOR]