Optical Position Sensing In Free Space Optical Communication

In this thesis the performance of three estimators, (center of gravity, template matching and maximum likelihood (MLE)) to estimate the center of the beam on a photoemissive receiver array in a Free Space Optics (FSO) system, is compared in terms of mean square error. Simulations have been conducted in Matlab by generating a two dimensional nonhomogeneous Poisson process, and, mean square error is computed for three estimators. The cases of continuous and discrete arrays are also considered for various levels of signal-to-noise (SNR) ratio. Simulations have shown that the MLE gives the least mean squared error and especially performs significantly better than other estimators under poor SNR conditions

An Empirical Evidence of Human Capital Constraint towards Economic Growth

Human capital plays a crucial role in enhancing sustainable economic growth. The aim of this study is to investigate the long run linkage between economic growth and human capital and explore the problems facing by education and health sectors in Pakistan, how to remove these problems in order to increase Human Capital, eminence of Human Capital and Economic Growth also. For this purpose, this study has been taken annual time series data from 1977 to 2014 and employed co-integration technique to find out the results. This study has been used the data from WDI, SBP, and Economic Survey of Pakistan (various issues). The results of this study revealed strong positive and significant long run association between human capital and economic growth in Pakistan. It is also found by the study that current status of health and education sectors in Pakistan is very poor. This study may be useful for health and educational policy making and human capital formation to boost up economic growth in Pakistan. Keywords: Human capital, Economic Growth, Johansen Co-integration, Skilled Worker

Optimal Photodetector Size for High-Speed Free-Space Optics Receivers

The selection of an optimal photodetector area is closely linked to the attainment of higher data rates in optical wireless communication receivers. If the photodetector area is too large, the channel capacity degrades due to lower modulation bandwidth of the detector. A smaller photodetector maximizes the bandwidth, but minimizes the captured signal power and the subsequent signal-to-noise ratio. Therein lies an opportunity in this trade-off to maximize the channel rate by choosing the optimal photodetector area. In this study, we have optimized the photodetector area in order to maximize the channel capacity of a free-space optical link for a diverse set of communication scenarios. We believe that the study in this paper in general -- and the closed-form solutions derived in this study in particular -- will be helpful to maximize achievable data rates of a wide gamut of optical wireless communication systems: from long range deep space optical links to short range indoor visible light communication systems

Enteroenteric fistulae in ccute bowel ischemia

Gastrointestinal fistulae are classified as enteroenteric or enterocutaneous. Most gastrointestinal fistulae are formed after surgical procedures for inflammatory bowel disease or malignancy. For spontaneous enteroenteric fistulae, ischemia has been reported as a possible etiology. We report two cases of spontaneous enteroenteric fistulae arising after bowel ischemia; a 38-year male with a 10-day history of severe abdominal pain with fever and vomiting, and a 22-year female with a one-week history of abdominal pain and diarrhea. Arterial and venous thrombi in association with enteroenteric fistulae were identified on computed tomography. These cases point towards acute mesenteric ischemia as a rare cause of spontaneous enteroenteric fistulae. Surgical management of these fistulae can be effective in resolving this complication

Do financial development and energy efficiency ensure green environment? Evidence from R.C.E.P. economies

The issue of climate change and environmental degradation has been prevailing for the last few decades. Yet economies are further expanding due to free trade agreement which accelerates the trade of energy and carbon intensive commodities across the regions. A prominent example of such free trade is the Regional Comprehensive Economic Partnership (R.C.E.P.), which mostly remains ignored. The current research study explores the influence of financial development (F.D.) and energy efficiency (E.N.E.F.) on carbon emissions in the R.C.E.P. economies. Also, this study analyses the role of economic growth and renewable energy on environmental quality during the period from 1990 to 2020. Panel data approaches such as slope heterogeneity, crosssection dependence, and the second-generation panel unit root test are used. The non-normally distributed variables are found cointegrated. Therefore, a novel method of moments quantile regression is used. The results demonstrate that F.D. and economic growth are positively associated with CO2 emissions. At the same time, E.N.E.F. and renewable energy consumption (R.E.C.) significantly reduce the emissions level and promote a green environment in all quantiles. The environmental Kuznets curve is found valid in the R.C.E.P. economies. These results are robust as validated by Fully-Modified Ordinary Least Square – a parametric approach. A two-way significant causal association exists between carbon-economic growth, carbon-F.D., carbon- R.E.C., and carbon-E.N.E.F.. The findings suggest an enhancement in R.E.C., improvement in the E.N.E.F. approaches, and implications for green F.D. in the region

Impact of Delayed Pain to Needle and Variable Door to Needle Time On In-Hospital Complications in Patients With ST-Elevation Myocardial Infarction Who Underwent Thrombolysis: A Single-Center Experience.

Background Myocardial infarction is a life-threatening event, and timely intervention is essential to improve patient outcomes and mortality. Previous studies have shown that the time to thrombolysis should be less than 30 minutes of the patient\u27s arrival at the emergency room. Pain-to-needle time is a time from onset of chest pain to the initiation of thrombolysis, and door-to-needle time is a time between arrival to the emergency room to initiation of thrombolytic treatment. Ideally, the target for door-to-needle time should be less than 30 minutes; however, it is unclear if the door-to-needle time has a significant impact on patients presenting later than three hours from the onset of pain. As many of the previous studies were conducted in first-world countries, with established emergency medical services (EMS) systems and pre-hospital ST-elevation myocardial infarction (STEMI) triages and protocols, the data is not completely generalizable to developing countries. We, therefore, looked for the impact of the shorter and longer door-to-needle times on patient outcomes who presented to the emergency room (ER) with delayed pain-to-needle times (more than three hours of pain onset). Objective To determine the impact of delayed pain-to-needle time (PNT) with variable door-to-needle time (DNT) on in-hospital complications (post-infarct angina, heart failure, left ventricular dysfunction, and death) in patients with ST-elevation myocardial infarction (STEMI) who underwent thrombolysis. Methods and results A total of 300 STEMI patients who underwent thrombolysis within 12 hours of symptoms onset were included, which were divided into two groups based on PNT. These groups were further divided into subgroups based on DNT. The primary outcome was in-hospital complications between the two groups and between subgroups within each group. The pain-to-needle time was ≤3 hours in 73 (24.3%) patients and \u3e3 hours in 227 (75.7%) patients. In-hospital complications were higher in group II with PNT \u3e3 hours (p3 hours), has a significant impact on in-hospital complications with no difference in mortality