Sabbir Ahmed Khan

Solar Home System Components Qualification Testing Procedure and Its Effect in Bangladesh Perspective

Bangladesh has seen a proliferation of Solar Home System (SHS) in Off-grid areas as a substitute for grid electricity. Along with the demand, supply of low quality SHS components is increasing resulting in decreased SHS efficiency and adverse effect on the countrys economy. In this case standard testing methods for the SHS components can help us verify the standard of the components in markets thus increase reliability and efficiency of the whole system. This paper discusses about the standard qualification testing procedure, its necessity and effect in Bangladesh prospective. Here we present the testing procedures used to determine whether the SHS components meet IDCOL standards and our findings on the components in concern. Sample testing data from our lab is also integrated in the paper.

Current-voltage characteristics of CNTFET considering non-ballistic conduction: Effect of dielectric constant

Carbon nanotube is being considered as a prospective alternative for the existing Silicon technology in present days. The advancement of Silicon technology, at present, has slowed down considerably because of its various material issues and scaling limitations and so, carbon nanotubes have gained the attention of researchers around the world over. In this literature, the effect of change of dielectric constant of the gate material on the performance of carbon nanotube field effect transistor (CNTFET) with non-ballistic conduction is extensively investigated. It is found in this study that with the value of dielectric constant of the gate material greatly improves the current output of CNTFET considering Non-Ballistic conduction. In addition to this, the obtained results are compared with previously reported CNTFET with ballistic conduction data for a better perception of the non-ballistic conduction with effects. Also, the on and off state current ratios have been calculated and plotted in this work to further contrast the ballistic and non-ballistic conduction of CNTFET.

Low cost cylindrical lumen testing procedure in Bangladesh perspective

Due to having several Solar Home System components manufacturers, overall quality of LED lamps varies from organization to organization. This unstable quality is increasing with the number of SHS installation and thus the system inefficiency. Hence, testing of LED lamps used in SHS is very important. However, existing procedure using the integrated sphere system for lumen test is quite costly in our countrys perspective. Considering the situation, this research presents a low cost cylindrical procedure for lumen testing. The effectiveness of our novel system is tested in this paper. This research also includes the testing results from CARG lab, BRAC University.

Epitaxial growth controlled tailoring of Metal-Insulator (MI) Transition properties of rare earth correlated oxides

Strongly correlated electron devices using Metal Insulator Transition (MIT) Oxides are prospective alternatives along the new generation of high speed devices based on novel mechanisms. Taking the advantages of correlated electrons which are capable of forming a variety of electronic phases, MIT Oxides and Phase Change Materials (PCM) are treated as the frontiers of emergent device research. With the prospect of downsizing devices to the nanoscale regime, benefits over conventional semiconductor devices are attained. Aided by recent advances in fabrication technology, considerable improvements have been achieved to tailor the Metal-Insulator (MI) transition properties of MIT Oxides. In this study, the tailoring of MI transition properties for a particular group of MIT Oxides, namely the transition metal perovskite oxides of RNiO3 family are studied on the epitaxial platform. Finally, antiferromagnetism characteristics and anonymous resistivity inherent within those oxides are studied.