Household Income Dynamics and Wage Inequality In Bangladesh: Evidence From Hies 2010 And 2016

Al Mamun,MD. ARFANUZZAMAN,NUSRAT JAHAN NISHAT 중앙대학교 경제연구소 2023 Journal of Economic Development Vol.48 No.3

The study used the Household Income and Expenditure Survey (HIES) data from 2010 and 2016 of Bangladesh to examine the effects of human capital (education, experience) and social factors (age, gender, location, economic activity) on income using the OLS and IV (2SLS and GMM) regression methods. The study suggests that both education and experience positively affected income in both rural and urban areas. The gender wage gap, rural-urban wage gap, and industrial and service sector wage gap all climbed to 44.1 percent, 19.4 percent, and 5 percent, respectively, in 2016, much higher than in 2010. It has emerged that both urban males and females earn significantly more than their rural counterparts in both periods. The study found a wage dominance of the service sector over the agricultural and industrial sectors in 2016. Besides, the gap between the agricultural and non-agricultural sector’s wages decreased significantly in 2016, indicating decent wage growth in the agriculture sector. As both human capital and social factors have a remarkable contribution to income, strategic planning, and investment are required to reduce inequality and wage gaps and advance inclusive development in Bangladesh.

Experimental Investigation of Chloride Ion Penetration and Reinforcement Corrosion in Reinforced Concrete Member

Al Mamun, Md. Abdullah,Islam, Md. Shafiqul Korea Institute of Construction Engineering and Ma 2017 Journal of construction engineering and project ma Vol.7 No.1

This paper represents the experimental investigation of chloride penetration into plain concretes and reinforced concretes. The main objective of this work is to study the main influencing parameters affecting corrosion of steel in concrete. Plain cement concrete and reinforced cement concrete with different water-cement ratios and different cover depth were subjected to ponding test. Ponding of specimens were done for different periods into 10% NaCl solution. Depth of penetration of chloride solution into specimens was measured after ponding. Specimens were crushed and reinforcements were washed using $HNO_3$ solution and weight loss due to corrosion was calculated accordingly. There was a linear relationship between depth of penetration and water-cement ratio. It was also observed that, corrosion of reinforcing steel increases with chloride ponding period and with water-cement ratio. Corrosion of steel in concrete can be minimized by providing good quality concrete and sufficient concrete cover over the reinforcing bars. Water-cement ratio has to be low enough to slow down the penetration of chloride salts into concrete.

Effect of hot-casted NiO hole transport layer on the performance of perovskite solar cells

Mamun, Abdullah Al,Ava, Tanzila Tasnim,Abdel-Fattah, Tarek M.,Jeong, Hyeon Jun,Jeong, Mun Seok,Han, Seonhye,Yoon, Hargsoon,Namkoong, Gon Elsevier Science B.V., Amsterdam. 2019 SOLAR ENERGY -PHOENIX ARIZONA THEN NEW YORK- Vol.188 No.-

<P><B>Abstract</B></P> <P>NiO is extensively studied as a hole transport layer in perovskite solar cells but syntheses of NiO precursor involves toxic chemicals and time-consuming processes. Moreover, the synthesized NiO contains surface defects acting as trapping sites at the NiO/perovskite interfaces, resulting in poor charge extraction, hysteresis and light soaking. In this manuscript, we developed a non-toxic methodology for NiO precursor solution by using a simple mixture of NiO powder and HCl in an air environment. In addition, a new hot-casting technique was developed to successfully fabricate densely-packed, less defective NiO films. Interestingly, the hot-casting temperature was found to significantly affect morphology, film coverage and surface defects of NiO films. When a hot-casting temperature was below 100 °C, non-uniform NiO films were sparsely formed on the FTO surface and were characterized by defects in the form of hydroxyl groups and water on the surface. Such defective NiO films resulted in severe hysteresis and light soaking effect due to the trapped charges at the defective NiO/perovskite interface of perovskite solar cells. In contrast, when the hot-casting temperature was 120 °C, the NiO film formed densely-packed morphologies, covering the FTO surface. Furthermore, this film exhibited an ordered chemistry with strong Ni-O octahedral bonding and facilitated charge extraction at NiO/perovskite interface, resulting in a negligible hysteresis and light soaking. Finally, this non-toxic and simple method of fabricating NiO film will assist further development of perovskite solar cells.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A quick, simple, inexpensive, and non-toxic methodology was developed for preparing NiO precursor solution. </LI> <LI> A new hot-casting technique was developed to fabricate densely-packed, less defective NiO films. </LI> <LI> Hot-casted NiO resulted in a negligible hysteresis and light soaking of perovskite solar cells. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Issues in DSMC Application to the Prediction of Micro Nozzle Flow

Mamun Md Abdullah Al,Tae Ho Kim,Heuy Dong Kim 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.08

Seasonal Shift in Community Structure of Periphytic Ciliates in Estuarine Waters in the Northern Bay of Bengal, Bangladesh

Mamun Abdullah Al,Rahman Muhammed Forruq,Aysha Akhtar,Md. Wahidul Alam,Mohammad Nurul Azim Sikder,Alan Warren,Henglong Xu 한국해양과학기술원 2018 Ocean science journal Vol.53 No.4

To investigate the seasonal heterogeneity of the periphytic ciliate communities, a 1-year baseline survey was conducted in the Karnaphuli River estuary, northern Bay of Bengal, Bangladesh. A total of 54 ciliate species were recorded, including seven common and 14 dominant species. Maximum species number was in autumn whereas maximum abundance was in winter; the minimum for both occurred in summer. Multivariate analyses, i.e., canonical analysis of principal coordinates (CAP) and principal co-ordinates analysis (PCoA), revealed a clear seasonal heterogeneity of community structure and environmental variables. Multivariate correlation analysis (RELATE) demonstrated that the community structure of the periphytic ciliate communities was significantly correlated with environmental variables, and best matching analysis (BIOENV) indicated that heterogeneity of community patterns was mainly driven by water temperature, pH, dissolved oxygen, total dissolved solids and nutrients. Species richness and diversity peaked in autumn whereas species evenness peaked in summer. These results suggest that environmental conditions shape periphytic ciliate community structure, which is a potentially useful bio-indicator of estuarine water quality.

Effects of Tunneling Current on STM Imaging Mechanism for Alkanethiol Self-assembled Monolayers on Au(111)

Mamun, Abdulla Hel Al,Son, Seung-Bae,Hahn, Jae-Ryang Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.1

We investigated the effects of tunneling current on scanning tunneling microscopy (STM) images of 1-octanethiol (OT) and 1-decanethiol (DT) self-assembled monolayers (SAMs). At a low tunneling current, the domain boundaries and ordered alkanethiol molecules were clearly resolved. As the tunneling current was increased at a constant bias voltage, however, the STM images showed disordered structures of the OT and DT SAMs. As the tunneling current was reduced back to low values, the ordered structures of the alkanethiol molecules reappeared. The reversibility of the process suggests that the sulfur head groups did not rearrange under any of the tunneling current conditions. On the basis of our observations, which are inconsistent with the standard model for STM imaging of molecules on metal surfaces, we consider the STM imaging mechanism in terms of a two-region tunneling junction model.

Mapping Landslide Susceptibility Based on Spatial Prediction Modeling Approach and Quality Assessment

Al-Mamun,Park, Hyun-Su,JANG, Dong-Ho 한국지형학회 2019 한국지형학회지 Vol.26 No.3

The purpose of this study is to identify the quality of landslide susceptibility in a landslide-prone area (Jinbu-myeon, Gangwon-do, South Korea) by spatial prediction modeling approach and compare the results obtained. For this goal, a landslide inventory map was prepared mainly based on past historical information and aerial photographs analysis (Daum Map, 2008), as well as some field observation. Altogether, 550 landslides were counted at the whole study area. Among them, 182 landslides are debris flow and each group of landslides was constructed in the inventory map separately. Then, the landslide inventory was randomly selected through Excel; 50% landslide was used for model analysis and the remaining 50% was used for validation purpose. Total 12 contributing factors, such as slope, aspect, curvature, topographic wetness index (TWI), elevation, forest type, forest timber diameter, forest crown density, geology, landuse, soil depth, and soil drainage were used in the analysis. Moreover, to find out the co-relation between landslide causative factors and incidents landslide, pixels were divided into several classes and frequency ratio for individual class was extracted. Eventually, six landslide susceptibility maps were constructed using the Bayesian Predictive Discriminant (BPD), Empirical Likelihood Ratio (ELR), and Linear Regression Method (LRM) models based on different category dada. Finally, in the cross validation process, landslide susceptibility map was plotted with a receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) and tried to extract success rate curve. The result showed that Bayesian, likelihood and linear models were of 85.52%, 85.23%, and 83.49% accuracy respectively for total data. Subsequently, in the category of debris flow landslide, results are little better compare with total data and its contained 86.33%, 85.53% and 84.17% accuracy. It means all three models were reasonable methods for landslide susceptibility analysis. The models have proved to produce reliable predictions for regional spatial planning or land-use planning.

Genome-wide association study of body weight in Australian Merino sheep reveals an orthologous region on OAR6 to human and bovine genomic regions affecting height and weight

Al-Mamun, Hawlader A.,Kwan, Paul,Clark, Samuel A.,Ferdosi, Mohammad H.,Tellam, Ross,Gondro, Cedric BioMed Central 2015 Genetics, selection, evolution Vol.47 No.1

<P><B>Background</B></P><P>Body weight (BW) is an important trait for meat production in sheep. Although over the past few years, numerous quantitative trait loci (QTL) have been detected for production traits in cattle, few QTL studies have been reported for sheep, with even fewer on meat production traits. Our objective was to perform a genome-wide association study (GWAS) with the medium-density Illumina Ovine SNP50 BeadChip to identify genomic regions and corresponding haplotypes associated with BW in Australian Merino sheep.</P><P><B>Methods</B></P><P>A total of 1781 Australian Merino sheep were genotyped using the medium-density Illumina Ovine SNP50 BeadChip. Among the 53 862 single nucleotide polymorphisms (SNPs) on this array, 48 640 were used to perform a GWAS using a linear mixed model approach. Genotypes were phased with <I>hsphase</I>; to estimate SNP haplotype effects, linkage disequilibrium blocks were identified in the detected QTL region.</P><P><B>Results</B></P><P>Thirty-nine SNPs were associated with BW at a Bonferroni-corrected genome-wide significance threshold of 1 %. One region on sheep (<I>Ovis aries</I>) chromosome 6 (OAR6) between 36.15 and 38.56 Mb, included 13 significant SNPs that were associated with BW; the most significant SNP was OAR6_41936490.1 (<I>P</I> = 2.37 × 10<SUP>−16</SUP>) at 37.69 Mb with an allele substitution effect of 2.12 kg, which corresponds to 0.248 phenotypic standard deviations for BW. The region that surrounds this association signal on OAR6 contains three genes: <I>leucine aminopeptidase 3</I> (<I>LAP3</I>), which is involved in the processing of the oxytocin precursor; <I>NCAPG non-SMC condensin I complex, subunit G</I> (<I>NCAPG)</I>, which is associated with foetal growth and carcass size in cattle; and <I>ligand dependent nuclear receptor corepressor-like</I> (<I>LCORL</I>), which is associated with height in humans and cattle.</P><P><B>Conclusions</B></P><P>The GWAS analysis detected 39 SNPs associated with BW in sheep and a major QTL region was identified on OAR6. In several other mammalian species, regions that are syntenic with this region have been found to be associated with body size traits, which may reflect that the underlying biological mechanisms share a common ancestry. These findings should facilitate the discovery of causative variants for BW and contribute to marker-assisted selection.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1186/s12711-015-0142-4) contains supplementary material, which is available to authorized users.</P>

Pt and TCO free hybrid bilayer silver nanowire-graphene counter electrode for dye-sensitized solar cells

Al-Mamun, M.,Kim, J.Y.,Sung, Y.E.,Lee, J.J.,Kim, S.R. North Holland ; Elsevier Science Ltd 2013 Chemical physics letters Vol.561 No.-

Here we report a novel transparent conductive oxide (TCO) and Pt free silver nanowire and graphene nanoplatelet (AgNW-GNP) based hybrid counter electrode (CE) for dye-sensitized solar cells (DSSCs) having appreciable photovoltaic performances compared to reference Pt-FTO based DSSCs. Simple solution processed bilayer AgNW-GNP hybrid CEs were prepared to investigate its applicability in DSSCs based on their electrocatalytic and charge transport properties. DSSCs prepared with AgNW-GNP hybrid CEs containing the GNP loading of 0.88μg/cm<SUP>2</SUP> showed the photoconversion efficiency of 1.61+/-0.13% which is comparable with that of 1.87+/-0.15% made of standard Pt-FTO CEs.

Landslide Risk Assessment of Cropland and Man-made Infrastructures using Bayesian Predictive Model

Al-Mamun,장동호 한국지형학회 2020 한국지형학회지 Vol.27 No.3

The purpose of this study is to evaluate the risk of cropland and man-made infrastructures in a landslide-prone area using a GIS-based method. To achieve this goal, a landslide inventory map was prepared based on aerial photograph analysis as well as field observations. A total of 550 landslides have been counted in the entire study area. For model analysis and validation, extracted landslides were randomly selected and divided into two groups. The landslide causative factors such as slope, aspect, curvature, topographic wetness index, elevation, forest type, forest crown density, geology, land-use, soil drainage, and soil texture were used in the analysis. Moreover, to identify the correlation between landslides and causative factors, pixels were divided into several classes and frequency ratio was also extracted. A landslide susceptibility map was constructed using a bayesian predictive model (BPM) based on the entire events. In the cross validation process, the landslide susceptibility map as well as observation data were plotted with a receiver operating characteristic (ROC) curve then the area under the curve (AUC) was calculated and tried to extract a success rate curve. The results showed that, the BPM produced 85.8% accuracy. We believed that the model was acceptable for the landslide susceptibility analysis of the study area. In addition, for risk assessment, monetary value (local) and vulnerability scale were added for each social thematic data layers, which were then converted into US dollar considering landslide occurrence time. Moreover, the total number of the study area pixels and predictive landslide affected pixels were considered for making a probability table. Matching with the affected number, 5,000 landslide pixels were assumed to run for final calculation. Based on the result, cropland showed the estimated total risk as US $ 35.4 million and man-made infrastructure risk amounted to US $ 39.3 million.