Search results

The purpose of this paper is to describe how fabricate solar cell based‐on porous silicon (PS) prepared by electrochemical etching process is fabricated and the effect of porosity layer on the solar cell performance is investigated.

The techniques used include SiO₂ thermal oxidation, ZnO/TiO₂ sputtering deposition and PS prepared by electrochemical etching. Surface morphology and structural properties of porous Si were characterized by using scanning electron microscopy. Photoluminescence and Raman spectroscopy measurements were also performed at room temperature. Current‐voltage measurements of the fabricated solar cell were taken under 80 mW/cm² illumination conditions. Optical reflectance was obtained by using optical reflectometer (Filmetrics‐F20).

Pore diameter and microstructure are dependent on anodization condition such as HF: ethanol concentration, duration time, temperature, and current density. On other hand, a much more homogeneous and uniform distribution of pores is obtained when compared with other wafer prepared with different electrolyte composition.

PS is found to be an excellent anti‐reflection coating against incident light when it is compared with another anti‐reflection coating and exhibits good light‐trapping of a wide wavelength spectrum which produce high efficiency solar cells (11.23 per cent).

This study aims to develop a practical methodology to identify possible areas of improvements as well as exploring how to improve the health-care staff flow within a selected department in a hospital.

It focuses on showing how to properly study and analyze the health-care services and processes practiced at a selected department within a hospital. For this, several techniques like non-value-adding activities, time motion study, spaghetti diagram, layout analysis, etc. are used.

To test the proposed methodology, a neonatal intensive care unit (NICU) of a hospital in Oman was considered as a case study. The study revealed that this unit has several potential improvements capabilities. Further, this study also discussed possible areas of improvements of this case unit and suggested how such improvements can be implemented.

Several possible improvements are suggested and are discussed with the hospital authority, which can be clarified as the re-layout of the NICU rooms, reorganization of the store to improve the staff flow, increase the work efficiency, introduction of Help Us Support Healing policy, etc., which can enhance the entire operational system at the studied NICU.