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: Quantum efficiency & Diode. The organization has 618 authors who have published 940 publications receiving 10674 citations.

Performance Comparison of DFT-OFDM and Wavelet-OFDM with Zero-Forcing Equalizer for FIR Channel Equalization

Abstract: In conventional DFT based orthogonal frequency division multiplexing (OFDM), cyclic prefix (CP) is used to avoid the inter symbol interference (ISI) caused by a time dispersive channel. A solution has been proposed in literature, which involves replacing DFT with wavelet packet transform (WPT) in communication systems. WPT does not require CP and has the attraction of having much lower side lobes. However, in wavelet based multicarrier systems, channel equalization remains an open research area. In this article, a time-domain zero-forcing equalizer (ZFE) for wavelet packet based OFDM (WOFDM) is proposed. The performance comparison of DFT-OFDM and WOFDM is given for an arbitrary FIR channel with different types of wavelet packets. Simulation results show improvement in bit error rate (BER) performance for WOFDM.

Electrical characterization of the ITO/NiPc/PEDOT : PSS junction diode

Abstract: This paper reports on the fabrication and characterization of an ITO/NiPc/PEDOT?:?PSS junction diode. A thin film of nickel phthalocyanine (NiPc) was deposited by the thermal vacuum deposition method on indium tin oxide (ITO) used as a substrate. The current?voltage characteristics of the diode were measured at room temperature under dark condition and showed rectifying behaviour. The values of several electrical parameters such as ideality factor, barrier height, conductivity, and series and shunt resistances were calculated.

Humidity sensing properties of Cu2O-PEPC nanocomposite films

Abstract: A blend of copper oxide nanopowder (Cu2O), 3 wt.%, and poly-N-epoxypropylcarbazole (PEPC), 2 wt.%, in benzol was drop-casted on glass substrates with pre-deposited surface-type silver electrodes for the fabrication of Cu2O-PEPC nanocomposite thin films. The thicknesses of the Cu2O-PEPC films were in the range of 10–13 μm. The effect of humidity on the electrical properties of the nanocomposite films was investigated by measuring the capacitance and dissipation of the samples at two different frequencies of the applied voltage: 120 Hz and 1 kHz. The AC resistance of the samples was determined from the dissipation values, and the DC resistance was measured directly. The effect of ageing on the humidity sensing properties of the nanocomposite was observed. After ageing, it was observed that at 120 Hz and 1 kHz, under a humidity of up to 86% RH, the capacitance of the cell increased by 85 and 8 times, and the resistance decreased by 345 and 157 times, accordingly, with respect to 30% RH conditions. It was found that with an increase in frequency, the capacitance and resistance of the samples decreased. It is assumed that the humidity response of the cell is associated with the diffusion of water vapors and doping of the semiconductor nanocomposite by water molecules.

Moving toward green mobility: overview and analysis of electric vehicle selection, Pakistan a case in point

Abstract: Environmental concerns are on the rise around the world, as carbon emissions are increasing rapidly and which is one of the leading causes of global warming. These emissions come from different sectors but the biggest contribution comes from the transport sector. As countermeasures, countries are shifting toward electric vehicles, which are much greener modes of transportation. Currently, different types of electric vehicles are available in the market. The selection of a viable type of electric vehicle for a developing country like Pakistan needs proper evaluation. In this study, two techniques are used. Firstly, fuzzy Strength, Weaknesses, Opportunities, and Threats (SWOT) approach is used for the selection of a suitable vehicle for the future market of Pakistan. Secondly, fuzzy linear programming is used to check the viability of electric vehicles in the current market scenario. Using these techniques, hydrogen fuel cell vehicle is selected as the most advantageous vehicle for Pakistan’s future market and the hybrid electric vehicle comes out as the best alternative for the current market. The techniques and the case study of Pakistan are the main novelty of this study, as no literature exists on electric vehicles with these methods on Pakistan’s perspective. Based on the results, different recommendations are given to the policymakers of Pakistan. The recommended policies could make electric vehicles a prime competitor to the combustion vehicles in the current and future markets.