The dynamics and determinants of Kuwait's long-run economic growth

This paper develops a quarterly macro-econometric model for the Kuwaiti economy estimated over the period 1979Q2-2013Q1, allowing us to investigate the long-run role of oil income in the development of Kuwait as well as the direct effects of oil revenue, foreign output, and equity price shocks on real output. More specifically, we examine to what extent Kuwaiti real output in the long run is shaped by oil revenue through their impact on capital accumulation, and technological transfers through foreign output. Using the same modelling strategy we also explore the role of oil income in terms of long-run private and public sector output growth (separately). The estimates suggest that real domestic output in the long run is influenced by oil revenues and foreign output (a proxy for technological progress), and technological growth in Kuwait is on a par with the rest of the world. Furthermore, while we show that both oil revenues and foreign output drive growth in the public sector, it seems that technological progress is the main (and only) driver for private sector real growth. Finally, our results show that oil revenue and global equity market shocks have a large and significant long-run impact on Kuwait's real output and public sector GDP. In comparison, the effects of the foreign output shock is muted

Bilateral retrorenal colon-a case report

Ascending and descending colon normally lie in anterior pararenal space anterior to kidneys. Extension of colon behind kidney is rare. It is more frequently found on the left side behind lower pole of the left kidney. Bilateral retrorenal colon is rare. Its detection is important prior to Retrorenal, Percutaneous nephrolithotomy (PCNL) to avoid complications. We report a case of bilateral retrorenal colon detected incidentally in a case of obstructive jaundice

The impact of computer use in the development of mathematics teaching in primary education

The educational system in Kuwait is intended to provide primary and secondary students with required skills in order to operate in the technical careers commonly undertaken. However, mathematics education lags significantly behind other countries in Kuwait. In the 1997 and 2008 TIMMS international studies of primary and secondary mathematics achievement, Kuwait ranked near the bottom on almost all scores. Thus, improving mathematics education in Kuwait is an issue of serious concern. This research focuses on the question of whether mathematics teaching and learning in Kuwaiti primary schools (grade 4) can be improved through the use of computer-based tools for practice drills and constructive mathematics play. An observational intervention was used in a classroom of 24 children, where students took a pre-test for mathematics achievement, then engaged in a series of exercises through the term and were retested at the end of the term. This was accompanied by a series of in-services and teacher interviews that were conducted within the school, in order to discover attitudes about mathematics teaching and learning and to train teachers in the suggested approaches and techniques. A combined qualitative and quantitative approach included analysis of test scores and interviews with teachers and students. The overall outcomes of the study did show a slight increase in mathematics achievement scores. However, more importantly it showed an improvement in children's and teacher's attitudes to mathematics learning related to the introduction of constructive play activities (derived from the Cambridge University N-RICH program and selected for students based on level of achievement) Overall, the importance of this study is that it provides pragmatic information for Kuwaiti teachers and curriculum designers on improving mathematics teaching and learning.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Inhibition of weld corrosion in flowing brines containing carbon dioxide

The aim of this research was to study the effectiveness of a typical oilfield corrosion inhibitor, which is considered to be a green inhibitor (non toxic to the environment) in controlling internal corrosion of welded X65 pipeline steel in brines saturated with carbon dioxide at one bar pressure, under dynamic flowing conditions, over a range of temperatures. Several experimental configurations were used ranging from a simple flat plate design to a novel rotating cylinder electrode, to allow high shear stress to be achieved. The rotating cylinder electrode (RCE) apparatus was designed to allow steel from the weld metal, heat affected zone (HAZ) and parent material to be galvanically coupled and tested in high shear stress conditions. In producing the RCE, the three regions of the weld were identified by optical metallography and samples of each were machined to produce cylindrical electrodes, which were mounted on a motor driven shaft. Electrical connections were made to the three electrodes via a high quality slip-ring assembly. The galvanic currents flowing between the regions of the weld were recorded using zero-resistance ammeters and their self-corrosion rates were found by uncoupling the electrodes and performing polarization resistance measurements. For static conditions the inhibitor had an effective performance and after a short initial period during which film formation took place, at longer exposure times a dramatic reduction of corrosion rate was obtained. Under flowing conditions, both the galvanic currents and the self-corrosion rates were found to increase with the shear stress, as the rotational speed of the RCE was increased. The total corrosion rate of each weld region was assessed from the sum of the self-corrosion and galvanic contributions. In most cases, the weld metal and HAZ were shown to be cathodic to the parent material and this was considered to be a desirable situation as localised corrosion of the weld was minimised. However, in some circumstances, including inhibition of pre-corroded steel surfaces, a current reversal took place, which resulted in accelerated corrosion of the weld. These findings are explained in terms of the protective nature of the films that form on each region of the weld.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Building Energy Model Generation Using a Digital Photogrammetry-Based 3D Model

Buildings consume a large amount of energy and environmental resources. At the same time, current practices for whole-building energy simulation are costly and require skilled labor. As Building Energy Modeling (BEM) and simulations are becoming increasingly important, there is a growing need to make environmental assessments of buildings more efficient and accessible. A building energy model is based on collecting input data from the real, physical world and representing them as a digital energy model. Real-world data is also collected in the field of 3D reconstruction and image analysis, where major developments have been happening in recent years. Current digital photogrammetry software can automatically match photographs taken with a simple smartphone camera and generate a 3D model. This thesis presents methods and techniques that can be used to generate a building energy model from a digital photogrammetry-based 3D model. To accomplish this, a prototype program was developed that uses 3D reconstructed data as geometric modeling inputs for BEM. To validate the prototype, an experiment was conducted where a case-study building was selected. Photographs of the building were taken using a small remotelycontrolled Unmanned Aerial Vehicle (UAV) drone. Then, using photogrammetry software, the photographs were used to automatically generate a textured 3D model. The texture map, which is an image that represents the color information in the 3D model, was semantically annotated to extract building elements. The window annotations were iii used as inputs for the BEM process. In addition, a number of algorithms were applied to automatically convert both the 3D model and the annotated texture map into geometry that is compatible for a building energy model. Through the prototype, pre-defined templates were used with the geometric inputs to generate an EnergyPlus model (as an example building energy model). The feasibility of this experiment was verified by running a successful energy simulation. The results of this thesis contribute towards creating an automated and user-friendly photo-to-BEM method

Isotopic-mass dependence of the A, B, and C excitonic band gaps in ZnO at low temperatures

Low temperature wavelength-modulated reflectivity measurements of isotopically engineered ZnO samples have yielded the dependence of their A, B, and C excitonic band gaps on the isotopic masses of Zn and O. The observed dependence is analyzed in terms of the band gap renormalization by zero-point vibrations via electron-phonon interaction and the volume dependence on isotopic mass. A simplified, two-oscillator model, employed in the analysis, yields zero-point renormalizations of the band gaps, -154 +/- 14 meV (A), -145 +/- 12 meV (B), and -169 +/- 14 meV (C), for ZnO with natural isotopic composition

Investigating Calotropis Procera natural dye extracts and PDOT:PSS hole transport material for dye-sensitized solar cells

Received: February 24th, 2021 ; Accepted: May 2nd, 2021 ; Published: May 4th, 2021 ; Correspondence: [email protected] this work, natural dye extracts from Calotropis Procera are used as the main dyesensitizer in solar cells. The Calotropis plant is a non-food item capable of surviving the harsh climate of the United Arab Emirates. Its incorporation into dye-sensitized solar cells is tested by constructing various cells, whose performance was also compared to that of more common chlorophyll-based dye extracts (i.e. spinach) as well as compared against a baseline cell sensitized with a synthetic ruthenium dye. The performance of the Calotropis-based cells was in general better than those with other natural sensitizers, but of course scored lower efficiency results when compared to cells built with synthetic dyes (0.075% compared to 5.11%). The advantage in using a natural sensitizer include facile extraction and preparation, low cost and abundance, since the Calotropis source has no competing applications in terms of food, livestock feed, etc. The figureof-merit of cell output vs. cost for such cells makes them a good contender for further research and development effort to overcome the obvious drawbacks of stability and service longevity. Adding a hole-transport material to the cells in the form of PEDOT:PSS was also attempted to assess the enhancement it could provide to the cells. This did not yield the desired results and more experiments have to be done to better understand the interaction of each added layer to the original cell design

The Impact of COVID-19 Lockdowns on Air Quality: A Systematic Review Study

Background: The purpose of this article was to review the published literature and evaluate the association between air quality/air pollution and the lockdown/stay-at-home orders during COVID-19 pandemic. Our goal is to identify the various environmental factors, such as urban and rural air quality, which were affected by the lockdown during the coronavirus disease (COVID-19) pandemic. Methods: We searched PubMed (2000–2021) for eligible articles using the following: (1) Aerosol[Title/Abstract], AND (2) air quality[Title/Abstract] OR air pollution[Title/Abstract] AND (3) COVID-19[Title/Abstract]. A total of 39 articles were identified through the search conducted in PubMed. We first screened the title and the abstract of those 39 articles for eligibility. A total of 24 articles did not meet the eligibility criteria and were excluded based on the title and the abstract review. The 15 remaining articles were assessed in full text for eligibility and data extraction. After a full-text review, 3 articles were excluded. Finally, a total of 12 selected articles were confirmed for data extraction. Results: Among the 12 studies, 5 articles focused on the effect of the air pollution, fine particulate matter, and air pollutants of COVID-19 pandemic’s lockdown, while 1 article targeted the relationship between the weather/air quality and COVID-19 death rate during lockdown. In addition, 5 papers focused on the association between the environmental factors, air pollution and air quality and COVID-19 mortality rate. Finally, 1 research study paper aimed to study the COVID-19 positivity rate and the effect of air quality during the stay-at-home order or the lockdown which was occurred in March 2020. It is important to note that it has been found that an increase in the average PM2.5 concentration was correlated with a relative increase in the COVID-19 test positivity rate. This explains the increase in the number of COVID cases during the period of the wildfire smoke from August to October 2020 (1). Conclusion: The findings indicate that the COVID-19 lockdown has significant impact on the air quality across the world. The lockdown significantly reduces the air pollutants such as NO2, CO, O3 and Particulate Matter PM2.5 and PM10. This reduction led to a much healthier and safer outdoor air and hence improved the air quality during the lockdown/stay-at-home orders. More research is needed to validate that the air pollutants (NO2, CO, O3, PM2.5 and PM10) have a significant impact on the COVID-19 mortality and fatality rates