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.

Mathematical modeling and control law design for 1DOF Quadcopter flight dynamics

Abstract: The purpose of this research is the modeling and Linear Control of Quad copter through pitch, roll, yaw and thrust command Interface. This research starts with derivation of nonlinear mathematical model of quad copter dynamics that consists of 6 degree of freedom(DOF) motions. The non-linear model is then linearized around equilibrium point and then 3DOF kinematics is extracted in order to design stabilizing and tracking control of three angular motions (Pitch, Yaw and roll). The Open loop transfer function of each DOF rotation motion shows that quad copter is highly unstable without any damping factor in linear mode. A Proportional integrator and differentiator(PID) controller is designed to control and stabilization of 3DOF rotations, controlling the four actuators independently in simulation. The real time 1DOF operation is done on designed Test rig in which the relation between thrust, Average RPM is evaluated and desired pitch pitch response is achieved by closed loop PID controller on Test rig. To support the above arguments, the simulated results as well as experimental results are presenented and compared.

Runtime Invocation Analysis of API Objects in Large Code Base

Abstract: Software systems use several third party libraries via their available interfaces popularly known as the application programming interface (API). The runtime usage of the API in an object-oriented software system can be defined by several characteristics including the type and number of API objects created, the methods invoked on those objects, and the source code locations from where the objects were created or invoked during their lifetime. These characteristics can be used to identify the source code locations exhibiting different types of runtime behavior which can be used for program comprehension, debugging, performance monitoring and fault detection. In this paper, we define object invocation model based on above-mentioned characteristics. We also propose an implementation framework that can be used to extract key model parameters from any source code. The Java Collections API is one of the most widely used Java APIs. We demonstrate effectiveness of our proposed approach by analyzing object invocation model for Java Collection API in a large open source project.

Two Dimensional Materials based Heterostructures for Photosensing Applications

Abstract: Graphene (Gr) and transition metal dichalcogenides (TMDC) have wide scope in electronic and optoelectronic industry because of incredible optical and electrical properties. The study investigates the utilization of molybdenum disulfide-graphene (MoS 2 -Gr) hybrid field effect transistor (FET) as photosensor. The photo-current response of hybrid FET was studied for source-drain voltages(V ds ) range from 1 to 5 V. The important optical figure of merits such as photoresponsivity (R λ ) and external quantum efficiency (EQE) are calculated to evaluate the performance of FET. Enhancement in the optical performance of FET is observed. MoS 2 -Gr divulges high R λ (3.34 × 103 AW-1) while the EQE of hybrid FET (1.8 × 104) is higher than that of individual structures. This methodology of fabricating TMDCs-Gr based hybrid devices opens new doors for advances in highly efficient photosensor for sensing and optoelectronic applications.

Synthesis and characterisation of carbon nanotube reinforced copper matrix nanocomposites

Abstract: This work presents the multi-walled carbon nanotubes (CNTs) reinforced copper matrix nanocomposites that were synthesised by a chemical based route commonly known as molecular level mixing. These nanocomposites can exhibit much superior properties as compared to other metal matrix composites. A copper acetate monohydrate sample was mixed with CNTs in ethanol followed by drying, calcination, and reduction. This resulted in the formation of copper nanoparticles attached with uniformly dispersed CNTs. The samples at each process step were characterised by using Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), and scanning electron microscopy (SEM). Emphasis is placed on the functionalisation of the CNTs and its role in deagglomeration in order to achieve uniform mixing with the copper metal matrix. Sintering of the powder was done at 900°C for two hours and SEM studies revealed good retention and uniform distribution of CNTs in the copper-based matrix of the nanocomposite samples indicating considerable benefits of the synthesis process.

Examining the weak-form efficiency and opportunities for technical analysis in the foreign exchange market: a new insight from trading partners of Pakistan

Abstract: Foreign exchange market prediction is one of the most challenging problems which continues to distress both researchers and financial analysts, because investors can earn abnormal profits only if market are inefficient. The objective of this study is to analyse the weak-form efficiency of foreign currencies of major trading partners of Pakistan which includes China, Germany, Hong Kong, Italy, Japan, Kuwait, Saudi Arabia, UAE, the UK and the USA. We use a battery of parametric and non-parametric test (measure of normality, autocorrelation and Q-statistics, run test, Kolmogorov-Smirnov test and variance ratio tests) on the most recent dataset. Time period spans from January 1, 2006 to January 31, 2017 on daily, weekly and monthly basis which provides robustness of our findings. This study reveals that foreign exchange market are weak-form inefficient, therefore there exist opportunities for a technician in terms of technical trading strategies in the foreign exchange market of major trading partners of Pakistan. This study has important implication for technical trading strategies, developing diversified portfolios and for the application of risk management techniques in foreign exchange market.