Ghulam Ishaq Khan Institute of Engineering Sciences and Technology

About: Ghulam Ishaq Khan Institute of Engineering Sciences and Technology is a education organization based out in Topi, Pakistan. It is known for research contribution in the topics: Thin film & Quantum efficiency. The organization has 618 authors who have published 940 publications receiving 10674 citations.

Bio-Synthesized Tin Oxide Nanoparticles: Structural, Optical, and Biological Studies

Abstract: This research was planned to synthesize a biological potent nanomaterials via an eco-friendly process to combat the diseases causing bacteria and the free radicals generated inside the body. For this purpose, a green synthesis process was employed to prepare SnO2 nanoparticles by utilizing leaf extract of Populus ciliate, and they were characterized via different physico-chemical techniques. The crystallite size of SnO2 nanoparticles was found to be 58.5 nm. The calculated band gap energy of SnO2 nanoparticles was 3.36 eV. The SnO2 nanoparticles showed 38, 49, 57, and 72% antioxidant activity at concentrations of 100, 200, 300, and 400 L with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid) (ABTS) assays. The antibacterial effects of prepared SnO2 nanoparticles were studied using the agar well diffusion method against Gram-positive bacteria (S. pyogene and S. aureus) and Gram-negative bacteria (K. pneumoniae and E. coli). Both the antioxidant activity and antibacterial activity were seen to increase with increasing the concentration of the nanoparticles.

Photoanode annealing effect on charge transport in dye-sensitized solar cell

Abstract: Solar energy is an abundantly available form of clean and renewable energy resource that can be used to generate electricity using many different photovoltaic technologies. Dye-sensitized solar cells (DSSCs) have attracted attention of researchers due to their low cost and easy fabrication processes, when compared to conventional silicon-based photovoltaic devices. Performance enhancement of DSSCs continues to be the subject of recent research. In this work, FTO/TiO2/N719/electrolyte/Pt-type conventional DSSCs were fabricated with and without heat treatment of the FTO/TiO2 photoanode before sensitization and Pt counter electrode. Results of the photovoltaic and impedance spectroscopic measurements are reported and discussed. The photovoltaic data reveals relatively higher performance of the cell made after heat treatments of the photoanode and the counter electrodes. The objective of this research is to study the reason for high performance obtained employing the annealed photoanode. The overall power conversion efficiency and short-circuit current density of the device made after heat treatment are observed higher than the one without heat treatment by 165% and 206%, respectively. The impedance spectroscopic studies also confirmed high performance of the cell made after the heat treatments.

VLCS: A Novel Clock Synchronization Technique for TDMA-based MAC Protocols in VANETs

Abstract: Local clock synchronization of nodes is one of the most critical problems with Time-Division Multiple Access (TDMA)-based protocols for dissemination of warning messages in Vehicular Ad hoc Networks (VANETs). Unsynchronized nodes’ clocks make time slot reservations inefficient, which results in channel collisions at a large scale. In this paper, we propose a novel cluster-based Vehicle-to-Vehicle Local Clock Synchronization (VLCS) technique, which is composed of two phases to synchronize all nodes in a VANET to a commonly shared clock. The first phase performs inter-cluster clock synchronization, whereas the second phase accomplishes intra-cluster clock synchronization where each member node synchronizes its clock with the corresponding cluster head. Simulation results demonstrate significant improvement of VLCS over an eminent VANETs clock synchronization technique.

Comparative Modal Analysis of Gasketed and Nongasketed Bolted Flanged Pipe Joints: FEA Approach

Abstract: It is widely known that resonance can quickly lead to failure in vibrating bolted flanged pipe joints. Condition monitoring is performed time to time in some industries for smooth operation of a sy...

Extraction of Electronic Parameters of PEDOT:PSS-PVA/n-Si Heterojunction Diode

Abstract: Using spin coating, a PEDOT:PSS-PVA/n-Si device has been fabricated by depositing the composite of conducting polymer PEDOT:PSS and poly(vinyl alcohol) on n-Si substrate. The current-voltage measurements of the device have been evaluated at room temperature in dark. The PEDOT:PSSPVA/ n-Si structure demonstrated the rectifying behavior. The various electronic parameters such as rectification ratio, turn on voltage, ideality factor, reverse saturation current, barrier height, series and shunt resistances were extracted from the IV characteristics of this diode. The values of ideality factor and series resistance were also verified by using Cheung functions. In addition, the conduction mechanism in the device was also investigated by I-V curves.