Sector-wise dividend payment by all listed companies in Dhaka stock exchange : an empirical analysis

Purpose: The purpose of this article is to examine the sectorwise dividend payment of all the listed companies in the Dhaka Stock Exchange (DSE). This paper also indicates the highest and lowest percentage of dividend paid by companies in each sector, as well as illustrates the reason for distributing such amount of dividend. Design/methodology/approach: The empirical analysis was done by using the last fifteen years (i.e., 2004-2018) of dividend payment by all listed firms in DSE. Data was collected from the secondary sources to perform the analysis. On collected data, average dividend amount was calculated for each listed company by adding the percentage of cash and stock dividend paid by those companies. Trend analysis was performed on the average dividend to see which company among all listed companies is distributing a high or low percentage of dividend to their shareholders' over the years. Findings: The results from this article show that companies in the declining industry fail to meet their shareholders’ expectations in terms of dividend payment. On the other hand, companies in booming industries are consistently disbursing dividend for their shareholders’. Besides, companies are in the growth stage, and the multinational companies are distributing a considerable percentage of dividend. Practical implications: The results of this article will be helpful for the fund managers’, investment analysts’ and investors’ who makes decisions to invest in the capital market because the paper presented the historical average dividend payment by listed companies. Originality/value: This article presents the average dividend payment by companies listed in stock exchange in an emerging economy, also finds out sector-wise dividend payment and suggests some remedial for companies.peer-reviewe

Trends of the major porin gene (ompF) evolution

OmpF is one of the major general porins of Enterobacteriaceae that belongs to the first line of bacterial defense and interactions with the biotic as well as abiotic environments. Porins are surface exposed and their structures strongly reflect the history of multiple interactions with the environmental challenges. Unfortunately, little is known on diversity of porin genes of Enterobacteriaceae and the genus Yersinia especially. We analyzed the sequences of the ompF gene from 73 Yersinia strains covering 14 known species. The phylogenetic analysis placed most of the Yersinia strains in the same line assigned by 16S rDNA-gyrB tree. Very high congruence in the tree topologies was observed for Y. enterocolitica, Y. kristensenii, Y. ruckeri, indicating that intragenic recombination in these species had no effect on the ompF gene. A significant level of intra- and interspecies recombination was found for Y. aleksiciae, Y. intermedia and Y. mollaretii. Our analysis shows that the ompF gene of Yersinia has evolved with nonrandom mutational rate under purifying selection. However, several surface loops in the OmpF porin contain positively selected sites, which very likely reflect adaptive diversification Yersinia to their ecological niches. To our knowledge, this is a first investigation of diversity of the porin gene covering the whole genus of the family Enterobacteriaceae. This study demonstrates that recombination and positive selection both contribute to evolution of ompF, but the relative contribution of these evolutionary forces are different among Yersinia species

Experimental and Numerical Evaluation of a Steamline Behaviour Using Local Approach

Results of the experimental and numerical comparative analysis of steamline pipes have been presented. New pipes and the pipes used for more than 117,000 hours at 540 °C under pressure of 42 bars have been simultaneously tested. This testing has been carried out because frequent failures of the equipment components exposed to elevated temperatures, such as steam pipelines, make it necessary to pay particular attention to the analysis of the materials used. The most frequent failures were those connected with occurrence of cracks, particularly expressed in case of steel 14MoV6 3. Local approach to fracture has been developed for complete understanding of fracture mechanism. This approach combines theoretical, experimental and numerical solution

Advantage of use of activated flux-cored wire instead of solid wire with the mag welding process from the mechanical properties aspect

The objective of this paper is the analysis and evaluation of the quality of the new flux-cored wire designed for the MAG welding process that was developed and produced using special laboratory equipment. Experimental welding was performed with the new activated flux-cored wire and classic solid wire with changing of welding parameters and shielding gas composition (100 % CO2 and gas mixtures of Ar + CO2 + O2)

Numerical simulation of the plunge stage in friction stir welding alloys EN AW 2024 T 351 and EN AW 7049A T 652

Tema ovog rada je proučavanje faze probijanja korišćenjem numeričkog modela. Analizirana je promena temperature i sile probijanja u toku faze probijanja postupka zavarivanja trenjem mešanjem za legure aluminijuma visoke čvrstoće EN AW 2024 T 351 i EN AW 7049A T 652, pri različitim brzinama rotacije alata. Numerički rezultati pokazuju da maksimalne temperature u postupku zavarivanja trenjem mešanjem mogu biti povećane sa povećanjem brzine rotacije alata i da su temperature manje od temperature topljenja materijala koji se zavaruje. Pri istim brzinama rotacije alata, registrovana je veća temperatura kod legure aluminijuma EN AW 2024 T 351 i veća sila probijanja - otpor materijala kod legure EN AW 7049A T 652. Sa povećanjem brzine rotacije alata, sila probijanja može biti smanjena. Trodimenzionalni model konačnih elemenata faze probijanja je razvijen korišćenjem ABAQUS programskog paketa za proučavanje termomehaničkih procesa faze probijanja. Spregnuti termo-mehanički model konačnih elemenata koristi proizvoljnu Lagranž-Ojlerovu formulaciju, Džonson-Kukov zakon i Kulonov zakon trenja. U ovoj analizi se temperatura, pomjeranje i mehaničke reakcije posmatraju istovremeno. Generisanje toplote u postupku zavarivanja trenjem mešanjem se može podeliti na tri dela:generisanje toplote trenjem od čela alata, generisanje toplote trenjem od trna alata i generisanje toplote od plastičnih deformacija u blizini trna alata.This paper investigates the plunge stage using numerical modeling. Change of temperature and plunge force have been analyzed during the plunge stage of the FSW procedure for high hardness aluminum alloys EN AW 2024 T 351 and EN AW 7049A T 652, at different speed of tool rotation. Numerical results indicate that the maximum temperature in the FSW process can be increased with the increase of the rotational speed and that temperature is lower than the melting point of the welding material. Higher temperature was registered at the aluminum alloy EN AW 2024 T 351 at the same speed of tool rotation, and higher plunge force - resistance of material was registered at the alloy EN AW 7049A T 652. When the rotational speed is increased, the plunge force can be reduced. A three-dimensional finite element model (FEM) of the plunge stage was developed using the commercial code ABAQUS to study the thermo-mechanical processes involved during the plunge stage. A coupled thermo-mechanical 3D FE model using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and the Coulomb's Law of friction. In this analysis, temperature, displacement and mechanical responses are determined simultaneously. The heat generation in FSW can be divided into three parts: frictional heat generated by the tool shoulder, frictional heat generated by the tool pin, and heat generated by material plastic deformation near the pin region

Numerical simulation of the plunge stage in friction stir welding alloys EN AW 2024 T 351 and EN AW 7049A T 652

Tema ovog rada je proučavanje faze probijanja korišćenjem numeričkog modela. Analizirana je promena temperature i sile probijanja u toku faze probijanja postupka zavarivanja trenjem mešanjem za legure aluminijuma visoke čvrstoće EN AW 2024 T 351 i EN AW 7049A T 652, pri različitim brzinama rotacije alata. Numerički rezultati pokazuju da maksimalne temperature u postupku zavarivanja trenjem mešanjem mogu biti povećane sa povećanjem brzine rotacije alata i da su temperature manje od temperature topljenja materijala koji se zavaruje. Pri istim brzinama rotacije alata, registrovana je veća temperatura kod legure aluminijuma EN AW 2024 T 351 i veća sila probijanja - otpor materijala kod legure EN AW 7049A T 652. Sa povećanjem brzine rotacije alata, sila probijanja može biti smanjena. Trodimenzionalni model konačnih elemenata faze probijanja je razvijen korišćenjem ABAQUS programskog paketa za proučavanje termomehaničkih procesa faze probijanja. Spregnuti termo-mehanički model konačnih elemenata koristi proizvoljnu Lagranž-Ojlerovu formulaciju, Džonson-Kukov zakon i Kulonov zakon trenja. U ovoj analizi se temperatura, pomjeranje i mehaničke reakcije posmatraju istovremeno. Generisanje toplote u postupku zavarivanja trenjem mešanjem se može podeliti na tri dela:generisanje toplote trenjem od čela alata, generisanje toplote trenjem od trna alata i generisanje toplote od plastičnih deformacija u blizini trna alata.This paper investigates the plunge stage using numerical modeling. Change of temperature and plunge force have been analyzed during the plunge stage of the FSW procedure for high hardness aluminum alloys EN AW 2024 T 351 and EN AW 7049A T 652, at different speed of tool rotation. Numerical results indicate that the maximum temperature in the FSW process can be increased with the increase of the rotational speed and that temperature is lower than the melting point of the welding material. Higher temperature was registered at the aluminum alloy EN AW 2024 T 351 at the same speed of tool rotation, and higher plunge force - resistance of material was registered at the alloy EN AW 7049A T 652. When the rotational speed is increased, the plunge force can be reduced. A three-dimensional finite element model (FEM) of the plunge stage was developed using the commercial code ABAQUS to study the thermo-mechanical processes involved during the plunge stage. A coupled thermo-mechanical 3D FE model using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and the Coulomb's Law of friction. In this analysis, temperature, displacement and mechanical responses are determined simultaneously. The heat generation in FSW can be divided into three parts: frictional heat generated by the tool shoulder, frictional heat generated by the tool pin, and heat generated by material plastic deformation near the pin region

The bio-ethanol production with the thin stillage recirculation

In this paper, the bioethanol production with the thin stillage recirculation in mashing was investigated. The mashing was performed with recirculation of: 0, 10, 20 and 30 % of the thin stillage. The thin stillage recirculation was repeated six times. In the experiment without the thin stillage, the recirculation bioethanol yield (compared to the theoretical yield) was 97.96 %, which implicates that the experiment conditions were chosen and performed well. With the addition of the thin stillage, the bioethanol yield increased and was above 100 %. Higher bioethanol yield than 100 % can be explained by the fact that the thin stillage contains carbohydrates, amino acids and yeast cells degradation products. The bioethanol yield increased with the increased number of thin stillage recirculation cycles. Dry matter content in fermenting slurry increased with the increased thin stillage quantity and the number of the thin stillage recirculation cycles (8.04 % for the first and 9.40 % for the sixth cycle). Dry matter content in thin stillage increased with the increased thin stillage quantity and the number of thin stillage recirculation cycles. Based on the obtained results it can be concluded that thin stillage recirculation increased the bioethanol yield. The highest bioethanol yields were obtained with recirculation of 10% thin stillage

Structural integrity assurance of casing pipes in the oil and gas industry

The exploitation of casing steel pipes used in oil and gas drilling rigs typically involves a corrosive atmosphere, high pressures and elevated temperatures. These conditions can affect the initiation and development of defects in the material, which can jeopardize t he s afe s ervice o f t he s ystem. I n t his work, a n assessment of the integrity of a damaged pipe, manufactured by high frequency contact welding (HF) of API J55 steel, is presented. The influence of an initial defect (machined surface crack) on the pipe structural integrity is analysed. Besides the defects at the internal surface, which is in contact with the transported fluid, casing pipes are also exposed to damage at the external surface, which is why such configuration is examined here. The analysed surface crack is in an axial direction, bearing in mind that this type of defect is the most severe for the cylindrical pressurised components. Internal pressure testing is conducted on a pipe closed by dished ends. The values of fracture parameters, crack mouth opening displacement CMOD and J integral, were tracked during the experiment. The applied procedure for J integral determination (so-called direct measurement) can be applied both on standard specimens and on structures. It includes the use of combined experimental - computational procedure. Finite element analysis is used for determining the criteria for the pipe failure, regarding both crack growth initiation and plastic collapse of the ligament. The size of the crack is varied in the finite element models, in order to determine the influence of its size on the maximum loading. Simplified 2D models are also examined, with the aim of determining the applicability of such approach. Based on the obtained results, criteria for the integrity assessment of the pipe are discussed

Failure prediction of gas and oil drilling rig pipelines with axial defects

Working conditions of casing pipes in drilling rigs can significantly influence the initiation and development of damage in the material, and therefore also the safe service of the entire system. In this work, an integrity assessment of a steel pipe with initial defect (machined surface crack) is presented. The position of this defect is on the external surface; unlike transport pipes, where internal surface is often endangered due to the contact with the fluid, casing pipes are often exposed to damages at the external surface. Analyzed crack is in axial direction, bearing in mind that this type of defect most significantly decreases the load carrying capacity of the cylindrical pressurized components. A pipe segment exposed to internal pressure is analyzed experimentally and numerically, using the finite element method. The experimental setup included the tracking of crack mouth opening displacement (CMOD) values, as well as J integral, which is determined by application of direct measurement. Criteria for pipe failure are determined on finite element models of the pipe; fracture initiation and plastic collapse are considered as failure mechanisms. The size of the crack is varied in the finite element models; several 3D models with different crack sizes (length and depth) are evaluated. Dependence of maximum internal pressure on the defect size is obtained. 2D plane strain models are also examined, with an aim to determine the applicability limits of this simplified approach. Based on the obtained results, integrity assessment criteria for the analyzed geometries are discussed