Energy consumption, CO2 emissions and the economic growth nexus in Bangladesh: cointegration and dynamic causality analysis

The paper investigates the existence of dynamic causality between the energy consumption, environmental pollutions and economic growth using cointegration analysis for Bangladesh. First, we tested whether any long run relationship exist using Johansen bi-variate cointegration model which is complemented with auto-regressive distributed lag model introduced by Pesaron for the results robustness. Then, we tested for the short run and the long causality relationship by estimating bi-variate vector error correction modeling framework. The estimation results indicate that a unidirectional causality run from energy consumption to economic growth both in the short and the long run; a bi-directional causality from electricity consumption to economic growth in long run but no causal relationship exists in the short run. A uni-directional causality run from CO2 emissions to energy consumption in the long run but it is opposite in the short run. CO2 granger cause to economic growth both in the short and in the long run, which is conflicting to the familiar environmental Kuznets curve hypothesis. Our results are different from existing analysis for electricity consumption and economic growth, however. The result of dynamic linkage between energy consumption and economic growth significantly reject the ‘neo-classical’ assumption that energy use is neutral to economic growth. Hence clearly an important policy implication, energy can be considered as a limiting factor to the economic growth in Bangladesh and conservation of energy may harm economic spurs. Therefore, it is a challenge for the policy makers to formulate sustainable energy consumption policy to support smooth energy supply for sustainable economic growth

太陽光発電による電化と教育成果に対する含意 : 南アジアにおける実証的知見

広島大学(Hiroshima University)博士(学術)Doctor of Philosophydoctora

Preparation and characterization of suitable insulating and transparent conducting thin films for thin film electroluminescent devices by sol-gel process

Thin film electroluminescent (TFEL) displays are attractive because they are light, have low power consumption, wide viewing angle and long lifetime, are extremely rugged and can be used in hostile environments. Recently, there has been a renewed interest in thin film electroluminescent devices because of their promising application to head mounted displays for use in automobiles, aircraft, microsurgery and virtual reality applications. Both conventional and inverted thin film electroluminescent device structures consist of insulating film, transparent conducting film and luminescent layer. In a thin film electroluminescent device, the luminescent layer is sandwiched between two insulating layers. Electrodes outside both insulating layers are used to apply an electric field, with one electrode being transparent. These thin films are found to be sensitive to preparation conditions and can be prepared by a variety of methods, such as, magnetron sputtering, chemical vapour deposition, reactive electron beam evaporation, reactive thermal deposition, spray pyrolysis, laser ablation and more recently by sol-gel process. Nowadays, the sol-gel process is a wellaccepted technology for the preparation of thin films, monoliths, fibers and monosized powders. Compared to conventional thin film forming processes such as CVD, evaporation or sputtering, sol-gel film formation requires considerably less equipment and is potentially less expensive; however the most important advantage of sol-gel processing over conventional coating methods is the ability to control precisely the microstructure of the deposited film, i.e., the pore volume, pore size and surface area. The sol-gel process is a method where the substrate to be coated is dipped into a liquid solution containing the active material. When the substrate is removed from the solution a thin layer remains. On exposure to the atmosphere a hydrolysis reaction takes place which solidifies the liquid film. In this work, all the thin films have been prepared by using sol-gel process. Insulating films of titanium dioxide and tantalum oxide were prepared from titanium and tantalum alkoxides respectively and their characteristics have been investigated. The most important requirements for the insulating layers are high dielectric constant and high electric field strength. The dielectric constants of the films were calculated from the maximum capacitance of the Al/film/Si structure. The maximum dielectric constants for Ti02 and Ta20 5 films were approximately 50 and 82 respectively annealed at 700°C in oxygen. These results suggest that the Ti02 and Ta2Os thin film can be used as a high dielectric constant insulating layer in thin film electroluminescent devices. Highly conductive and transparent aluminum-doped zinc oxide thin films have been prepared from the solution of zinc acetate and aluminum nitrate in ethanol by the sol-gel process. The effect of changing the aluminum-to-zinc ratio from 0 to 5 at. % and annealing temperature from 0 to 700°C in air, oxygen and nitrogen has been investigated. The resistivities of thin films were measured as a function of annealing temperature and also as a function of aluminum dopant concentration in the solution. As-deposited films have high resistivity and high optical transmission. Annealing of the as-deposited films in atmosphere leads to a substantial reduction in resistivity. The films have a minimum value of resistivity of 1.3xl0'4 Q-cm for 0.8 at. % aluminum-doped zinc oxide annealed at 500°C in nitrogen and a maximum transmission of about 88% when deposited on glass substrates. X-ray diffraction measurements employing CuKa radiation were performed to determine the crystallinity of the ZnO:Al films which showed that the films were polycrystalline with a hexagonal structure when annealed at higher temperatures in air, oxygen and nitrogen. Transparent conductive indium tin oxide (ITO) thin films have been prepared by a solgel process. The starting solution was prepared by mixing indium chloride dissolved in acetylacetone and tin chloride dissolved in ethanol. 0-20 % by weight Sn-doped indium oxide (ITO) films were prepared by heat-treatment at above 400°C. The electrical, optical and structural properties of ITO thin films were investigated. The electrical resistivity was measured by using four-point probe method. The ITO thin films containing 10 wt.% Sn showed the minimum resistivity of p = 8.0xl0'4 Q-cm annealed at 500°C in nitrogen. The films have an optical transparency up to 89% at 900 nm. X-ray diffraction measurements employing CuKa radiation were performed to determine the crystallinity of the ITO films which showed that the ITO films were polycrystalline with a cubic bixbyite structure annealed in air, oxygen and nitrogen. Aluminum doped zinc oxide thin films have been deposited on titanium dioxide and tantalum oxide films on glass by sol-gel process. The resistivity of ZnO:Al thin films deposited on titanium dioxide and tantalum oxide films on glass have a minimum value of 2.5xl0'3 Q-cm and 9.6xl0'4 Q-cm respectively annealed at 500°C in nitrogen. ZnO:Al thin films deposited on titanium dioxide film on glass have a higher resistivity than that deposited on glass. This increase in resistivity on titanium dioxide film is due to the diffusion of titanium into the zinc oxide layer. Indium tin oxide thin films have been deposited on titanium dioxide and tantalum oxide films on glass for thin film electroluminescent devices. The resistivity of ITO films deposited on titanium dioxide and tantalum oxide films has a minimum value of 9.5x1 O'4 Q-cm and 9.0x10'4 Q-cm respectively annealed at 500°C in nitrogen which are as low as the resistivity of ITO films deposited on glass. This combination of transparent conductive ITO thin films and titanium dioxide or tantalum oxide insulating layer can be used for thin film electroluminescent devices

Microcredit, enhancement of entitlement and alleviation of poverty : an investigation into the Grameen Bank's role in Bangladesh

In developing countries, especially in Bangladesh, poor people are excluded from the formal financial sector credit services through the collateral requirement to receive a loan. Informal financial sector sources, especially moneylenders, are exploitative in nature. Therefore, poor people do not receive the minimum amount of capital, which is required to start any income generating activity, from either of the financial sector sources. The Grameen Bank initiated the microcredit programme in Bangladesh around 1976, to alleviate the poverty of poor households through providing them with the minimum amount of capital as credit without collateral and exploitation. The present study evaluates the impact of microcredit on the poverty of borrowing households. Both quasi-experimental as well as non-experimental designs have been formulated to achieve the objective. The survey-design covers one group of households (programme households), which have already received more than one loan, and another group of households (comparison households), which have just joined the programme. This study goes beyond earlier studies by developing a comprehensive framework, which covers income, consumption, assets, basic-needs, living standards, entitlement, poverty, and poverty risk of households, for assessing the impact of microcredit on the poverty of borrowing households. This study uses both subjective as well as objective measures of poverty for determining the poverty status of households. The present study compares income, consumption, basic-needs, some proxies for living standards, poverty, and poverty risk of programme households with those of comparison households to assess impacts of microcredit. On the basis of the results obtained, the study argues that microcredit increases income, consumption, expenditure, and assets of borrowing households. Through increasing income and assets, microcredit enhances entitlement of borrowing households. Microcredit also improves fulfilment of basic-needs and living standards of borrowing households. Finally, this study argues that microcredit reduces poverty risk and alleviates poverty of borrowing households significantly

Determinants of Stock Investment Decisions of Sub-urban Investors in Bangladesh

Stock market around the world regarded as one of the most dominant indicators of the economic development of a country. Although the economy of Bangladesh grows to ever apex in the year 2019, its capital markets show the worst condition ever and never represent the economic status of the country. Investors lost their confidence and their all rational investment decisions failed to yield capital gains over the years. Thus, the prime objective of this study is to explore the determining factors which instigate the sub-urban investors of Bangladesh in making their investment decisions in the stock market and to investigate the effects of socio-economic variables on the dominant factors. The study has been pursued through a questionnaire survey to collect data from the stock investors of suburban areas of Bangladesh.  Principal Component Analysis (PCA) has been used as a factor extraction method. Descriptive statistics, independent-samples t-test, ANOVA, and Post-hoc tests were employed as statistical tools. PCA derived eight factors and fundamental analysis becomes the most dominant factor that affects the suburban investors in making decisions about a stock. Factor analysis also indicated that investment training, technical analysis, investment literacy training, investment consultancy, trade house proximity, insider trading mechanism, macro-economic factors determine investment decisions. Results of inferential statistics revealed that gender difference affects technical analysis; education level has a large effect on investment training and investment length has an effect on fundamental and technical analysis. However, factors do not differ based on investors’ occupational background and investment training. Policymakers should give concentrated effort to stabilize the stock market as the investors are more concerned about fundamental and technical analysis as well as investment literacy. Keywords: Capital Market, Sub-urban Investors, PCA, Fundamental analysis, Socio-economic variables, Bangladesh DOI: 10.7176/EJBM/12-21-07 Publication date:July 31st 2020

Input switched closed-loop single phase SEPIC controlled rectifier with improved performances

DC power supply has become the driving source for some essential modern applications. Thereby, DC power conditioning has become a significant issue for engineers. Typically used rectifiers associated with a bridge structure is nonlinear in nature. Thereby, the current at input side of the rectifier contains harmonics, which also flow through the power line. The presence of harmonics causes several interruptions and reduce power quality. In this regard, a new close loop SEPIC controlled rectifier is proposed in this paper. The conventional scheme is arranged with a rectifier connected to a DC-DC converter, which is an open loop system. Consequently, such system cannot regulate voltage at load varying condition. The proposed SEPIC controlled rectifier can regulate voltage under load varying condition for a wide range. Additionally, the performance in terms of total harmonic distortion (THD) of input current and power factor at AC side are also within satisfactory range for the closed loop configuration. The controlled rectifier has four operating phases associated with switching states and input voltage polarity. The close loop configuration also incorporates a current and a voltage loop at the feedback path. The comparative studies have been performed among the proposed closed loop construction, the open-loop structure as well as the conventional construction. The effectiveness of the proposed controlled rectifier is verified in terms of THD and input power factor considering the results obtained from simulation

Factors Affecting Academic Performance of Undergraduate Students: Evidence from a Public University in Bangladesh

Academic result measured by Grade Point Average is often considered as the most dominant performance indicator of a student in most of developing countries like Bangladesh. Several prior studies have been conducted to determine the factors which act as control measures to the academic performance in tertiary level education. But the obtained results varied largely depending on the socio-economic context and education policy of the nations. The study aims at finding out the factors that affect the academic performance of students of a public university situated in the south-western part of Bangladesh and to assess the relative predictability of various factors on academic performance. A sample of 314 graduate students from different disciples was chosen based on a random sampling method. Principal Component Analysis (PCA) as a statistical tool has been used to extract factors affecting academic performance. Multiple Linear regression was run to predict the influence of these factors on the dependent variable. The academic factor that includes conventional exam system, teachers’ evaluation system, and academic study environment appeared as the most dominant determinant factors affecting academic performance. Other important factors such as the financial condition of students, family income, social media affiliation, part-time job, extra-curricular activities also dictate academic performance. Regression coefficient indicates that gender, higher secondary examination grades, sleeping duration, academic study hours have a significant influence on academic achievement. The study results will be useful to the students, academicians, guardians of the students, policymakers, and researchers to have a better understanding of determinants of academic achievement and taking appropriate measures accordingly. Keywords: Academic performance, PCA, Academic factors, demographic and socio-economic factors, Public university students, Bangladesh. DOI: 10.7176/JEP/12-5-07 Publication date: February 28th 202