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The purpose of this paper is to study the effect of liner surface texture on journal bearing performance. Modeling the profile curvature of the dimples or grooves is planned for different cases of texture surface under thermo-hydrodynamic condition (THD). The aim of this paper is to determine the effect the texture surface on the performance of journal bearing and specify the optimum shape for texture dimples.

The paper was opted for an exploratory study by applying finite difference method to solve the energy equation, the heat conduction equations and the Reynolds equation numerically. The lubricant film thickness is divided to a mesh of 640,000 points. The equations were solved for each point of the mesh by using a MATLAB code. For texture shape optimization, 24 cases of different texture shapes were selected which includes elliptical, triangle and square curvature shape.

The paper provides theoretical insights about the effect of texture shape on journal bearing performance. It was concluded that to get a high load-carrying capacity, the direction of curvature is preferably to be perpendicular to the sliding direction. The convex texture has higher load carrying capacity than concave texture. Finally, the surface with textures in channel form yields better overall performance than the surface with several dimples.

This paper fulfils an identified need to study how texture surface affects the performance of journal bearing under thermo-hydrodynamic conditions.

This study aims to show the dyeing behaviour of polyester fabrics using four novel heterocyclic disperse dyes.

The four dyes were synthesized based on 5, 5'-(1, 4-phenylene) bis (1, 3, 4-thiadiazol-2-amine) as a diazonium compound. The UV/Vis absorption spectroscopic data of these disperse dyes while dyeing polyester fabrics were investigated. Following this, the dyeing properties of these dyes on polyester fabrics were investigated under acid condition.

The results showed that increasing the dyeing temperature from 80°C to 100°C led to an increase in dye uptake for all dyes, but further increases of the temperature to 130°C led to higher dye uptake for dye 3 as the dye exhaustion increased by about 50% from 55.9% to 91.4%.

This study is important as it introduces new dyes for the dyeing of polyethylene terephthalate (PET) fibres with colours that range from yellowish orange to bluish yellow and scarlet red and all with excellent brightness, levelness and depth of shade.

Comfortable outdoor workspaces are important for employees in business parks and urban areas. Prioritizing a pleasant thermal environment is essential for employee productivity, as well as the improvement of outdoor spaces between office buildings to enhance social activities and quality of outdoor workplaces in a hot arid climate has been subjected to very little studies Thus, this study focuses on business parks (BPs) landscape elements. The objective of this study is to enhance the user's thermal comfort in the work environment, especially in the outdoors attached to the administrative and office buildings such as the BPs.

This research follows Four-phases methodology. Phase 1 is the investigation of the literature review including the Concept and consideration of BP urban planning, Achieving outdoor thermal comfort (OTC) and shading elements analysis. Phase 2 is the case study initial analysis targeting for prioritizing zones for shading involves three main methods: social assessment, geometrical assessment and environmental assessment. Phase 3 entails selecting shading elements that are suitable for the zones requiring shading parametrize the selected shading elements. Phase 4 focuses on the optimization of OTC through shading arrangements for the prioritized zones.

Shading design is a multidimensional process that requires consideration of various factors, including social aspects, environmental impact and structural integrity. Shading elements in urban areas play a crucial role in mitigating heat stress by effectively shielding surfaces from solar radiation. The integration of parametric design and computational optimization techniques enhances the shading design process by generating a wide range of alternative solutions.

While conducting this research, it is important to acknowledge certain limitations that may affect the generalizability and scope of the findings. One significant limitation lies in the use of the shade audit method as a tool to prioritize zones for shading. Although the shade audit approach offers practical benefits for designers compared to using questionnaires, it may have its own inherent biases or may not capture the full complexity of human preferences and needs.

Few studies have focused on optimizing the type and location of devices that shade outdoor spaces. As a result, there is no consensus on the workflow that should regulate the design of outdoor shading installations in terms of microclimate and human thermal comfort, therefore testing parametric shading scenarios for open spaces between office buildings to increase the benefit of the outer environment is very important. The study synthesizes OTC strategies by filling the research gap through the implementation of a proper workflow that utilizes parametric thermal comfort.

The cement-filled PA12 manufactured by selective laser sintering (SLS) offers desirable mechanical properties; however, these properties are dependent on several fabrication parameters. As a result, SLS prototypes may exhibit orthotropic mechanical properties unless properly oriented in build chamber. This paper aims to evaluate the effects of part build orientation, laser energy and cement content on mechanical properties of cement-filled PA12.

The test specimens were fabricated by SLS using the “DTM Sinterstation 2000” system at which the specimens were aligned along six different orientations. The scanning speed was 914mm/s, scan spacing was 0.15mm, layer thickness was 0.1mm and laser power was 4.5–8Watt. A total of 270 tensile specimens, 270 flexural specimens and 135 compression specimens were manufactured and the tensile, compression and flexural properties of fabricated specimens were evaluated.

The experiments revealed orientation-dependent (orthotropic) mechanical properties of SLS cement-filled PA12 and confirmed that the parts with shorter scan vectors have enhanced flexural strength as compared with longer scan vectors. The maximum deviations of ultimate tensile strength, compressive strength and flexural modulus along the six orientations were 32%, 26% and 36%, respectively.

Although part build orientation is a key fabrication parameter, very little was found in open literature with contradictory findings about its effect on mechanical properties of fabricated parts. In this work, the effects of build orientation when combined with other fabrication parameters on the properties of SLS parts were evaluated along six different orientations.

Malnutrition is one of the serious public health problems especially for children and pregnant women in developing countries such as Bangladesh. This study aims to identify the risk factors associated with child nutrition for both male and female children in Bangladesh.

This study was conducted among 23,099 mothers or caretakers of children under five years of age from a nationally representative survey named Bangladesh Multiple Indicator Cluster Survey, 2019. This study used chi-square test statistic for bivariate analysis and multinomial logistic regression was used to evaluate the adjusted effects of those covariates on child nutritional status.

The prevalence of severely malnourished, nourishment was higher for males than females (5.3% vs 5.1%, 77.4% vs 76.8%) while moderately malnourished were higher for females (18.1% vs 17.4%). The findings from the multinomial model insinuated that the mother’s education level, wealth index, region, early child development, mother’s functional difficulties, child disability, reading children's books and diarrhea had a highly significant effect on moderate and severe malnutrition for male children. For the female children model, factors such as mother’s education level, wealth index, fever, child disability, rural, diarrhea, early child development and reading less than three books were significant for moderate and severe malnutrition.

There is a solution to any kind of problem and malnutrition is not an exceptional health problem. So, to overcome this problem, policymakers should take effective measures to improve maternal education level, wealth status, child health.

Students of mixed-ability learning together in one class is a challenge for all educators, especially in English as foreign language (EFL) contexts. Timed reading activity (TRA) is an activity that can help educators address the learning needs of students in such a context. The present study investigated the effectiveness of the TRA in enhancing EFL students' reading rate and reading comprehension as well as in making them aware of potentially wrong reading strategies that they may be using.

A classroom intervention was designed for a group of preparatory year (PY) students at a Saudi university. The study sample consisted of one intact class of 29 students. Data were collected from pre- and post-tests of students' reading rate and reading comprehension as well as progress charts. In addition, a questionnaire was used to identify the reading strategies used by the students.

The results showed that the TRA generally enhanced the reading comprehension and the reading rate of EFL mixed-ability students as well as raised their awareness of their use of wrong fast reading strategies.

The results of the study support the use of TRA as a remedial reading activity in EFL mixed-ability classes.

This paper examines the financial ratios that may have a significant effect on the efficiency in Malaysian listed companies. Nine financial ratios measure seven variables which are firm visibility, tangibility, working capital, leverage, liquidity, productivity and profitability.

Data are collected from 108 public listed companies in Malaysia. The data extracted from companies' annual reports for three years 2012–2014. STATA software analysis is used to examine these relationships.

The results show each of tangibility and liquidity have negative relationships with efficiency ratio. In against of that, profitability, working capital and productively positively link to efficiency. Leverage which is measured by two ratios – Debt ratio and Debt equity ratio – shows mix results. Debt ratio shows a positive but not significant relationship with efficiency ratio and Debt equity ratio shows a negative significant relationship with efficiency ratio.

The results benefit companies, investors, economists and governments regulators in Malaysia-to understand the efficiency determinants, so help to make the right decision to enhance the efficiency level in companies which leads to enhance the amount of investments which in turn, enhance the country's economy in general.

This study differs than previous studies number of aspects: first the study covers a three years' period between 2012 and 2014, this period presents the movement of Malaysian current into depreciation with more than 45 percent of its value. Second, in the Malaysia context, this study examines new variables such as firm visibility, tangibility, and productivity. Third, the results of this study will help managers, shareholders, investors, regulators and other parties to make right decisions that will enhance the level of firm efficiency which enhances the investments and the economy of Malaysia.

Due to the recent coronavirus (COVID-19) outbreak, a temporary interruption of education activities occurred all over the world. The sudden and quick shift from blended or face-to-face learning mode to the sole online learning mode affected the perceptions of students toward the Blackboard application and the usage. This study aims to investigate the perceptions of students toward the Blackboard application in the process of learning Preparatory Year (PY) English courses as the mere tool of learning and the impact of the students’ perceptions on the students’ use of Blackboard.

The results are based on a survey conducted with 228 of PY students: 1st level n = 126 and 2nd level n = 102 at Najran University. The data are analyzed to compare the two levels, as the students’ prior experience with Blackboard is not the same. The 2nd level students have prior experience of blended learning through Blackboard, whereas 1st level students have no prior experience of learning through Blackboard.

The data of the perceptions of both levels showed that 1st level students’ perceptions toward online learning of English via Blackboard were higher than 2nd level students. The data on the frequency of the use of the Blackboard application reflected the perceptions of students.

The findings suggest that the students’ prior experience of e-learning via Blackboard has an impact on the students’ perceptions.

The findings of the study contributed to the learning through the management systems research field and online learning of English during the COVID-19 outbreak.

The purpose of this paper is to examine how companies can achieve business excellence in a highly volatile, uncertain, complex and ambiguous (VUCA) environment. Within the literature about business excellence, there is a lack of understanding of the impact of today’s high VUCA on achieving business excellence. A new business concept, business excellence in a volatile, uncertain, complex and ambiguous environment (BEVUCA), will be illustrated so as to bridge this gap by considering the overall VUCA influence and the influences of each specific term individually.

The research incorporated a systematic literature review for three knowledge areas, namely: VUCA, business excellence and the management integration of quality and risk. The later knowledge area was reviewed because such diverse management thinking can help to achieve BEVUCA.

The research provided a definition for a new business concept and the systematic literature review identified 18 critical success factors so as to manage and excel under a high VUCA business environment. Finally a conceptual framework was developed for integrating quality management and risk management thinking so as to achieve BEVUCA.

BEVUCA can be used to close the current gap in the body of literature by providing a link between VUCA and business excellence, and hence advancing the discussion in these areas. Additionally, the BEVUCA conceptual framework can be used as guidance in integrating quality management and risk management to achieve the identified critical success factors.