Constellation Design of Geosynchronous Navigation Satellites Which Maximizes Availability and Accuracy over a Specified Region of the Earth

Currently, there are four Global Navigation Satellite Systems (GNSS) either being developed or in existence-GPS, GLONASS, Compass, and Galileo. Additionally, there are several Regional Navigation Satellite Systems (RNSS) planned or in existence, as well as numerous augmentation systems (which require a GNSS for operation). It can be anticipated that there will be interest in developing additional independent regional navigation satellite systems to cover areas of interest to particular countries or regions, who want to have their own system. In this paper, a genetic algorithm is used in an effort to determine near-optimal RNSS constellations. First, a cost function is setup, which involves a weighted combination of dilution of precision (DOP) values and percentage availability for any number of receiver locations on the ground (which themselves can be weighted). Effectively, using this approach it is easy to quantify the quality of coverage, in terms of measurement geometry, over a specific region of the earth. Next, a genetic algorithm is used in order to attempt to converge to the lowest-cost constellation possible

Evaluation of life quality and sleep problems in children presenting with headache to the pediatric neurology outpatient clinic

Aim: We aimed to investigate the quality of life (QL) and sleep habits (SH) of children presenting to the pediatric neurology outpatient clinic with headache. Methods: This prospective, cross-sectional and observational survey study included children aged 2-18 who presented to the pediatric neurology outpatient clinics of Dr. Ali Kemal Belviranlı Maternity and Children's Hospital or Konya City Hospital between April and August 2022. QL was assessed using the Pediatric Quality of Life Inventory (PedsQL) and sleep characteristics were evaluated using the Children’s Sleep Habits Questionnaire. Results: The study included 137 patients (56.2% girls) with a mean age of 153.54±34.5 months at presentation. All patients were diagnosed with primary headache; 51.8% had migraine and 48.2% had tension-type headache. Quality of life scores were 69.07±14.96 according to child self-assessment and 66.39±15.37 according to parental assessment. The mean score on the sleep habits questionnaire was 48.01±7.68, and 9.5% of the patients had good sleep quality. Subscale scores showed that the greatest adverse effects on QL were in the areas of emotional functioning and school functioning. Conclusions: Clinical assessment of patients’ QL and SH is important for individualizing treatment and approach in pediatric primary headache

IS THERE AN INFORMAL EMPLOYMENT WAGE PENALTY IN EGYPT?

This paper considers the private sector wage earners in Egypt and examine their wage distribution during 1998-2012 using Egyptian Labor Market Panel Survey. We first estimate Mincer wage equations both at the mean and at different quantiles of the wage distribution taking into account observable characteristics. Then we make use of the panel feature of the data and estimate models taking into account unobservable characteristics. We also consider the possibility of nonlinearity in covariate effects and estimate a variant of matching models. In all cases we find a persistent informal wage penalty in the face of extensive sensitivity checks. It is smaller when unobserved heterogeneity is taken into account and larger at the top than at the bottom of the conditional wage distribution. We also examine the informal wage penalty over time during the study period and in different groups according to experience and education. The informal wage penalty has increased recently over time and is larger for the better educated but smaller for the more experienced

Is There an Informal Employment Wage Penalty in Egypt?

This paper considers the private sector wage earners in Egypt and examine their wage distribution during 1998-2012 using Egyptian Labor Market Panel Survey. We first estimate Mincer wage equations both at the mean and at different quantiles of the wage distribution taking into account observable characteristics. Then we make use of the panel feature of the data and estimate models taking into account unobservable characteristics. We also consider the possibility of nonlinearity in covariate effects and estimate a variant of matching models. In all cases we find a persistent informal wage penalty in the face of extensive sensitivity checks. It is smaller when unobserved heterogeneity is taken into account and larger at the top than at the bottom of the conditional wage distribution. We also examine the informal wage penalty over time during the study period and in different groups according to experience and education. The informal wage penalty has increased recently over time and is larger for the better educated but smaller for the more experienced

Is There an Informal Employment Wage Penalty in Egypt?

This paper considers the private sector wage earners in Egypt and examine their wage distribution during 1998-2012 using Egyptian Labor Market Panel Survey. We first estimate Mincer wage equations both at the mean and at different quantiles of the wage distribution taking into account observable characteristics. Then we make use of the panel feature of the data and estimate models taking into account unobservable characteristics. We also consider the possibility of nonlinearity in covariate effects and estimate a variant of matching models. In all cases we find a persistent informal wage penalty in the face of extensive sensitivity checks. It is smaller when unobserved heterogeneity is taken into account and larger at the top than at the bottom of the conditional wage distribution. We also examine the informal wage penalty over time during the study period and in different groups according to experience and education. The informal wage penalty has increased recently over time and is larger for the better educated but smaller for the more experienced

Public versus Private Sector Wage Gap in Egypt: Evidence from Quantile Regression on Panel Data

This paper considers the public and private sector wage earners in Egypt and examines their wage distribution during 1998-2012 using Egyptian Labor Market Panel Survey. We estimate the public-private sector wage gap with Mincer wage equations both at the mean and at different quantiles of the wage distribution. In this process we take into account observable and unobservable characteristics of the individuals using the panel feature of the data with a fixed effects model. We address sector of employment selection issue for both males and females. We find that there is very little evidence of sample selection in our data. Therefore, we present both the selection corrected results and the results with no selection correction. We find a persistent public sector wage penalty for males and public sector wage premium for females in the face of extensive sensitivity checks. They are larger when unobserved heterogeneity is taken into account for males but insignificant for females. They are similar across the quantiles for males but, smaller at the top than at the bottom of the conditional wage distribution for females. We further examine the public sector wage gap over time and in different sub-groups according to age and education. The public sector wage penalty for males has decreased recently over time and is larger for the better educated and younger. We also find substantial regional differences in public sector wage gap for males

Is There an Informal Employment Wage Penalty in Egypt?

This paper considers the private sector wage earners in Egypt and examine their wage distribution during 1998-2012 using Egyptian Labor Market Panel Survey. We first estimate Mincer wage equations both at the mean and at different quantiles of the wage distribution taking into account observable characteristics. Then we make use of the panel feature of the data and estimate models taking into account unobservable characteristics. We also consider the possibility of nonlinearity in covariate effects and estimate a variant of matching models. In all cases we find a persistent informal wage penalty in the face of extensive sensitivity checks. It is smaller when unobserved heterogeneity is taken into account and larger at the top than at the bottom of the conditional wage distribution. We also examine the informal wage penalty over time during the study period and in different groups according to experience and education. The informal wage penalty has increased recently over time and is larger for the better educated but smaller for the more experienced