Institution
Ghulam Ishaq Khan Institute of Engineering Sciences and Technology
Education•Topi, Pakistan•
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.
Papers published on a yearly basis
Papers
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15 Nov 2010TL;DR: In this article, the authors present statistics of path loss for 60 GHz millimeter wave propagation channel simulations that are performed in the presence of humans in different indoor environments, where the human bodies are considered as randomly distributed cylinders in a room.
Abstract: This paper presents statistics of path loss for 60 GHz millimeter wave propagation channel simulations that are performed in the presence of humans in different indoor environments. A deterministic propagation model is used as an experimental tool to investigate the narrowband characteristics of the channel. The indoor radio propagation channel is modeled by using ray tracing and humans are modeled as perfectly conducting cylinders. The human bodies are considered as randomly distributed cylinders in a room. By varying both the number of persons and room size their effect on the received signal strength i.e. its fading distribution has been studied statistically. For a fixed room size as the number of persons increase, the variance of path loss increases due to more variations in the received signal. The variance decreases as the room size increases for a fixed number of persons. It was found that change in the dimensions of the rooms for a given area caused the statistics of path loss to change.
2 citations
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TL;DR: In this article, numerical analysis of structural engineering of conventional LED has been presented to enhance the performance of green light-emitting diodes (LEDs), and the proposed structure with composition-graded electron blocking layer as well as thickness-graded last quantum barrier and last quantum well shows improved radiative recombination rate, lower efficiency droop and higher light output power at high current density in comparison to other devices.
Abstract: To enhance the performance of green light-emitting diodes (LEDs), numerical analysis of structural engineering of conventional LED has been presented. Our proposed structure with composition-graded electron blocking layer as well as thickness-graded last quantum barrier and last quantum well shows improved radiative recombination rate, lower efficiency droop and higher light output power at high current density in comparison to other devices. The observed improvements are because of better electron and hole confinement as well as improved hole transportation inside the active region.
2 citations
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TL;DR: In this paper, the authors proposed that high reflection surfaces and polarization rotators can be designed using planar stratified metamaterials (MTMs), which are composed of strong chiral, dielectric, double negative, chiral nihility, and single negative MTM slabs.
Abstract: In this paper, it is proposed that high reflection surfaces and polarization rotators can be designed using planar stratified metamaterials (MTMs). For this purpose, structures used in design are composed of strong chiral, dielectric, double negative, chiral nihility, and single negative MTM slabs. To investigate these multilayered structures, reflection and transmission coefficients are analytically computed using transfer matrix method. The expressions depend on frequency, angle of incidence, optical width of slab, and material parameters. The structures are tested for numerical values and then optimized results are presented. For each case, structure is composed of odd number of infinite length slabs. These structures can be used in filters, radomes, and polarization conversion devices.
2 citations
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01 Jan 2011TL;DR: In this paper, the goodness-of-fit of a continuous distribution for a set of n observations grouped into N equal probability intervals is considered and the chi-square test is shown to be optimal in terms of the Pitman's and the Kalenberg's intermediate asymptotic efficiencies.
Abstract: The problem of testing the goodness-of-fit of a continuous distribution for a set of n observations grouped into N equal probability intervals is considered. It is assumed that N → ∞ as n → ∞. Let η1, …, η N be the numbers of observations in the intervals. We show that within the class of tests based on statistics of the form fη1 + ⋯ + fη N the classical chi-square test is optimal in terms of the Pitman’s and the Kalenberg’s intermediate asymptotic efficiencies but it is much inferior to tests satisfying Cramer condition in terms of the Kalenberg’s strong intermediate and the Bahadur’s exact asymptotic efficiencies. For the chi-square statistic, a probability of large deviation result, likely to be of its own interest, is proved.
2 citations
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07 Jul 1997TL;DR: In this article, the authors used scatterometry to measure silylated wafers to detect unwanted variations in processing conditions so that corrective responses can be implemented, which is a technique that is rapid, non-destructive and sensitive to changes introduced by the silylation process.
Abstract: The silylation step in the top surface imaging process has been difficult to monitor and characterize for lack of appropriate metrology tools. Utilizing scatterometry to measure silylated wafers, we report successful monitoring of processing effects. Wafers were manufactured under nominally identical processing conditions. Applying scatterometry, we are able to discern location dependent variations within wafers. In addition, wafer to wafer variations are also observe. Both these variations are detrimental to yield. Variations in processing conditions cause modifications and perturbations in the gratings. Different gratings diffract light in a dissimilar manner. Processing conditions and their effects on the wafers are deduced from these measurements using computational analysis. This information is used to detect unwanted variations in processing conditions so that corrective responses can be implemented. This technique is rapid, non-destructive and sensitive to changes introduced by the silylation process.
2 citations
Authors
Showing all 626 results
Name | H-index | Papers | Citations |
---|---|---|---|
Wajid Ali Khan | 128 | 1272 | 79308 |
Shuichi Miyazaki | 69 | 455 | 18513 |
Muhammad Zubair | 51 | 806 | 10265 |
Mohammad Islam | 44 | 192 | 9721 |
Asifullah Khan | 38 | 192 | 5109 |
Muhammad Waqas | 32 | 383 | 7336 |
Rana Abdul Shakoor | 30 | 140 | 3244 |
Noor Muhammad | 29 | 160 | 2656 |
Abdul Majid | 28 | 231 | 3134 |
Muhammad Abid | 27 | 377 | 3214 |
Iftikhar Ahmad | 26 | 143 | 2500 |
Shaheen Fatima | 24 | 79 | 2287 |
Ghulam Hussain | 24 | 127 | 1937 |
Zubair Ahmad | 24 | 145 | 1899 |
Muhammad Zahir Iqbal | 23 | 129 | 1624 |