Vector Tracking Loop Design for Degraded Signal Environment

The performance of GPS degrades significantly in urban canyons and in indoor environments. There has been significant research in order to enhance the performance of a GPS receiver in such challenging environment but still the traditional GPS receivers fall short of optimal performance in degraded signal environment where the carrier to noise density ratio(?C/N?_0) drops significantly and when GPS signal is obstructed by the surrounding environment. Improving GPS receiver performance in GPS challenged environment has become one of the very important driving factors of ongoing research in the field of GPS technologies. This thesis presents a modern GPS receiver architecture which is based on vector tracking loops. Traditional GPS receivers employ scalar tracking loops for tracking the satellite signals. Scalar tracking loops treat each channel independently. Therefore aiding of weaker satellite signals is not possible by the stronger signals. In a standard GPS receiver a Delay Lock Loop is used to track the Pseudo-Random Noise (PRN) sequence and a Costas loop is used to track the carrier part of the signal. On the other hand, vector tracking loops process the signals in an aggregate way and can provide better tracking in degraded signal environment. The task of tracking and navigation is done in one algorithm by using an extended Kalman filter. Due to the coupling of tracking and navigation in one processor aiding of weaker signals by the stronger signals is present. With vector tracking approach GPS receiver can take advantage of the redundancy of the GPS measurements that is not possible in the traditional GPS receiver architecture. A vector delay lock loop based on non-linear discriminator function has been implemented in this thesis and its ability to reacquire signals after momentarily blockage has been studied. The simulation results show the better performance of VDLL than conventional tracking methods. /Kir1

Limnological Study of River Soan (Punjab), Pakistan

River Soan is one of the important aquatic systems of the Punjab province in Pakistan and flows into Indus River near Kalla Bagh (District Mianwali). In order to measure the quality of water and to evaluate planktonic community, an integrated monitoring system was applied from May to December 2001. During the study period total of 202 genera were observed of which 134 were of phytoplankton present in various phylums including Cyanophyta (22), Cyarophyta (7), Xanthophyta (5), Bacillariophyta (22), Euglenophyta (5), Chlorophyta (62), Chrysophyta (8), Pyrrophyta (1) and Cphryrotophyta (2). 53 genera of zooplankton were observed including Protozoa (33), Rotifera (8), Cladocera (7), Copepoda (4) and Aquatic insecta (1). In addition to phyto and zooplankton 3 genera of Charophyta and 11 genera of Macrophyta were observed. Diversity index of phytoplankton ranged from 4.6 to 13.5 and of zooplankton from 1.94 to 5.90. Water samples were collected on monthly basis for estimation of various physical and chemical water quality parameters i.e., water temperature (9-31 0C), light penetration (1.2-22.3 cm), viscosity (0.8570-1.0572 mNS m-2), conductivity (7-19 mv), surface tension (69.28-72.63 dynes cm-1), density (0.980-1.022 mg l-1), specifi c gravity (0.796-1.025), boiling point (95-98 0C), turbidity (0.02-0.48 mg l-1), pH (8-9), dissolved oxygen (4.6- 9.3 mg l-1), alkalinity (19-36 mg l-1), acidity 1.0-1.8 mg l-1), carbonates (0), bicarbonates (19-36 mg l-1), total solids (0.56-4.24 mg l-1), total dissolved solids (0.53-4.83) and total dissolved volatile solids (0.05-0.29). Among elements, sodium (22.50-168.75 ppm), potassium (3.94-12.31 ppm), calcium (2.75-34.25 ppm), strontium (0.00-0.47 ppm), magnesium (0.00 ppm) and zinc (0.00 ppm) were detected through atomic absorption while seasonal variation in planktonic diversity was analyzed by calculating the frequency of occurrence, relative abundance and diversity index of planktonic life. The overall water quality of the study site remained within safe limits throughout the study period

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Vector Tracking Loop Design for Degraded Signal Environment

The performance of GPS degrades significantly in urban canyons and in indoor environments. There has been significant research in order to enhance the performance of a GPS receiver in such challenging environment but still the traditional GPS receivers fall short of optimal performance in degraded signal environment where the carrier to noise density ratio(?C/N?_0) drops significantly and when GPS signal is obstructed by the surrounding environment. Improving GPS receiver performance in GPS challenged environment has become one of the very important driving factors of ongoing research in the field of GPS technologies. This thesis presents a modern GPS receiver architecture which is based on vector tracking loops. Traditional GPS receivers employ scalar tracking loops for tracking the satellite signals. Scalar tracking loops treat each channel independently. Therefore aiding of weaker satellite signals is not possible by the stronger signals. In a standard GPS receiver a Delay Lock Loop is used to track the Pseudo-Random Noise (PRN) sequence and a Costas loop is used to track the carrier part of the signal. On the other hand, vector tracking loops process the signals in an aggregate way and can provide better tracking in degraded signal environment. The task of tracking and navigation is done in one algorithm by using an extended Kalman filter. Due to the coupling of tracking and navigation in one processor aiding of weaker signals by the stronger signals is present. With vector tracking approach GPS receiver can take advantage of the redundancy of the GPS measurements that is not possible in the traditional GPS receiver architecture. A vector delay lock loop based on non-linear discriminator function has been implemented in this thesis and its ability to reacquire signals after momentarily blockage has been studied. The simulation results show the better performance of VDLL than conventional tracking methods. /Kir1

Self-reported Vocal symptoms among speech language pathologists dealing with children with hearing impairment and cerebral palsy

A cross-sectional study was conducted at the Ripah International University, Lahore, Pakistan from January to April, 2022 to evaluate and compare the Self-Reported Vocal symptoms among Speech Language Pathologists (SLP) practicing with children having Hearing Impairment (HI) and Cerebral Palsy (CP). The sample included 141 participants of both genders, aged 25 to 60 years, practicing with children with hearing impairment and cerebral palsy for at least one year. Vocal Tract Discomfort Scale (VTDS) and Voice Activity Participation Profile (VAPP) were utilised for data collection which was analysed using SPSS Ver-23. The study revealed no significant association of self-perceived vocal symptoms for SLPs catering to CP and HI children with p=0.303 and p=0.412 for VTDS and VAPP scores respectively and with higher mean scores for SLPs catering to CP children. Results revealed a total VTDS score of 40.26±13.10 with highest score for dryness, while highest VAPP mean score was noted for daily communication (53.82±23.20). Hence, there is no significant association of the speciality being catered to, while dryness is the commonest self-perceived symptom. Keywords: Cerebral Palsy, Hearing Impairment, Self-concept, Speech-Language Pathologist

Alternative Approach to Fitting First-Order Model to the Response Surface Methodology

In this paper, we present the computational procedure of the First-Order Model in Response Surface Methodology (RSM) in a new dimension. Firstly, we fit the First-Order Model to a 2k design by applying Yates’ technique to calculate the sum of squares of main effects and their interactions. Secondly, we prove that SS regression and SS linear are equivalent. Thirdly, we give a new idea for computing SS quadratic under the concept of unbalanced Completely Randomized Design. The formula used in this technique is numerically and mathematically equivalent to the existing technique. Lastly, we split the total variation in the responses into all possible sources with the help of a diagram

Impact of Perceived Organizational Support and Psychological Capital on Organizational Commitment among University’s Employees

The aim of this study was to find out the impact of perceived organizational support and psychological capital on organizational commitment among university’s employees. The target population for this study was the employees of the Muhammad Nawaz Sharif University of Agriculture Multan, Pakistan (MNSUAM). The study was based on a correlational research design, and total of 128 employees were sampled through a simple random sampling technique. Survey method was used for data collection. The instruments used for data collection included the Perceived Organizational Support Scale (POSS) Psychological Capital Questionnaire and Organizational Commitment Questionnaire The data was collected from 128 employees analyzed through Statistical Package for Social Sciences (SPSS). The results of this study revealed a significant correlation between dependent and independent variables. The regression analysis indicated significant impact of perceived organizational support on organizational commitment. Further, it was also indicated a significant impact of psychological capital on organizational commitment among university employees. No significant gender differences were found in terms of perceived organizational support and psychological capital and organizational commitment. However, the results indicated a difference in Job status in terms of perceived organizational support. The findings of this study suggest a significant role of study variables which would be helpful to conduct future studies in the area of public management, psychology, and more particularly, organizational psychology. Moreover, this study is also useful for designing an encouraging and supportive organizational environment for employees

Investigating the role of economic integration and financial development: Rebound effect and green ICT in BRICS

The increasing trend of information and communication technology (ICT) forced researchers and policymakers to check the direct and indirect effects of information and communication technology on environmental quality. This study explores the relationship between information and Communication Technology and ecological quality by including the ICT and the interaction term of ICT with financial development indicators. The study uses the data for the BRICS (Brazile, Russia, India, China, and South Africa) economies from 1996 to 2020. This study is a pioneering effort to identify the independent and overlapping effects of information and communication technology (ICT) and financial development indicators on environmental quality. Further, the study uniquely tried to explore the shape of a modified environmental Kuznets curve (EKC) based on ICT by introducing the squared term of ICT in the model. Driscoll Kraay's standard error analysis confirmed a positive significant relationship between ICT and environmental quality. Our findings, among other things, show that in Brazil, China, and South Africa, the finance, environment, and the effects of ICT interact, whereas, in India and Russia, there is no such evidence. To increase the benefits of ICT to the environment, policymakers in Brazil, China, and South Africa should take additional steps to improve their financial sectors. The ICT-based environmental Kuznets curve validated the inverted U shape EKC hypothesis. The study findings suggested that green innovation and technology should be introduced in information and communication technology to mitigate the harmful effect of human activities on the environment