Search results

To determine optimum design and operation parameters for ternary batch distillation under fixed product demand.

In this study, two different scenarios are considered. In the first scenario, the column specification (in terms of number of plates and vapour load) and product demand are given and the optimum operation policy is determined. In the second scenario, with a fixed batch time and product demand, the optimal design (in terms of number of plates and vapour load) and operation policy (in terms of reflux ratio profile) are determined. In both scenarios, maximisation of a profit function reflecting capital cost, operating cost and penalty due to under/over production and customer dissatisfaction is considered. A detailed dynamic model consisting of mass and energy balances with rigorous thermodynamic property calculation model is used. The optimisation problem is solved using modified simulated annealing algorithm.

Two ternary mixtures leading to easy and difficult separation were considered. The off‐cut production and recycling has been found to be more beneficial for difficult separation mixture than that for easy separation mixture. The net profit increases with over production more than under production of the products. This is because of the penalty imposed for customer dissatisfaction. It is better to over produce, as that will achieve the maximum profit and (at the same time) satisfy the customer. Finally, for a typical case study, the net profit with optimum design is found to be about 25 per cent more compared to the net profit obtained with fixed design.

Optimal design and operation of multicomponent batch distillation has received limited attention in the past. Also, these studies were not geared for fixed product demand scenario. The optimisation problem formulation considered in the past, led to unlimited production of products (based on the assumption that all products produced are saleable) to maximise the profitability. Also, there were no penalties for over or under production of the desired products, production of off‐cuts and customer dissatisfaction due to not meeting the order (amount of products and delivery time, etc.). In this work, for the first time, these issues are addressed in the optimisation problem formulation.

In this paper, a review of materials selection methods is presented. It initially discusses the importance of materials selection in various fields of scientific study particularly in engineering design. Various tools and methods for the selection of materials are reviewed. These include materials handbook, materials data‐bases, materials selection charts, artificial intelligence systems, and other computeraided materials selection systems.

This study aims to explore employee green behavior in higher education institution (HEI) laboratories in the Kingdom of Bahrain.

A qualitative approach was used to explore the green behavior experiences of individuals working in HEI laboratories. In-depth interviews were conducted with nine participants selected via purposive sampling. Thematic analysis was performed on the collected data using ATLAS.ti 9 software.

The analysis of the collected data identified five themes related to the green behavior in HEI laboratories. These themes, ranked in descending order of frequency, are conserving, avoiding harm, transforming, influencing others and taking initiative. The conserving theme accounted for one-third of the subcodes, as did the avoiding harm theme. The final one-third of subcodes was distributed among the remaining three themes.

This study conducted virtual interviews and coincidentally interviewed only female participants. The findings contribute to the existing literature on the themes of green behavior among laboratory staff in HEIs and provide valuable insights for university managers and sustainability coordinators in shaping policies to promote environmentally friendly practices and address negative practices.

Despite existing studies on environmental practices in various workplace settings, the exploration of green behavior in HEI laboratories in the Kingdom of Bahrain from the employee perspective remains limited. This study presents a significant opportunity for researchers to explore sustainability in HEI laboratories and for policymakers to develop corresponding strategies.

The purpose of this study is to reduce energy consumption in bakeries. Due to fulfill this demand, quite a few parameters such as energy and exergy efficiency, energy waste and fuel consumption by different traditional flatbreads bakeries (Sangak, Barbari, Taftun and Lavash should be monitored and their roles should not be neglected.

In the present study, experimental measurements and mathematical modeling are used to scrutinize and investigate the effects of the aforementioned parameters on energy consumption by bakeries.

The results show that by doing reported methods in this paper, the wasted energy of the walls can be decreased by about 65 per cent; and also, by controlling the combustion reaction to perform with 5 per cent excess air, the wasted energy of excess air declines by about 90 per cent. And finally, the energy and exergy efficiency of bakeries is increased, and as a result, the annual energy consumption of Sangak, Barbari, Taftun and Lavash bakeries diminish about 71, 59, 57 and 40 per cent, respectively.

As evidenced by the literature review, it can be observed that neither numerical studies nor experimental investigations have been conducted about energy and exergy analyses of Iranian machinery traditional flatbread bakeries. It is clear that due to a high preference of Iranians to use the traditional bread and also the popularity of baking this kind of bread in Iran, if it is possible to enhance the traditional oven conditions to decrease the loss of natural gas instead of industrializing the bread baking, the energy consumption in the country can be optimized.

Reverse osmosis (RO) has become an important method of desalination to meet the ever-growing water needs around the world. Its integration with renewable energy source (RES) reduces the environmental impact of gas emissions and cost of conventional fossil energy sources. The optimal sizing of energy sources to power RO desalination system is intended mainly to minimize the annualized cost of the system and by extension minimize freshwater cost while maximizing production.

In this study, a mathematical optimization approach is used to determine the optimal energy mix, which includes grid power, diesel generator and a photovoltaic (PV) module to supply an RO desalination unit. Three cases of optimal sizing approach were compared. Case 1 is a system with only grid power and diesel generator as energy sources; Case 2 has PV incorporated in the energy supply mix while Case 3 has the three energy sources and a Time of Use (TOU) demand response program on the demand side.

The results of implementing the optimization models show that Case 3 turnout the highest freshwater production (1,521 m³/day) at a unit cost of 1.36$/m³ when compared to Case 1 with daily freshwater production of 1,250 m³/day at a unit cost of 1.68$/m³ and Case 2 having a daily freshwater production of 1,501 m³/day at a unit cost of 1.33$/m³.

The integration of RES to power desalination system with application of TOU demand response is the significance of this study.

Paint drying is a very important process in an industry where shorter drying time for productivity and lower energy consumption for production cost are required while maintaining the product’s painting quality. In the present study, a drying process in a line-type paint drying furnace equipped with nozzles for hot air supply and moving conveyer belt to dry painted automotive parts is numerically simulated for the flow and heat transfer inside the furnace to evaluate the quality of the drying or baking at the end of the drying process in a production line.

A baking window for a specific paint is used for judging the local degree of baking (DOB) of the painted parts, which can be useful to identify under-baked or over-baked locations of the painted parts, and hence the quality of the baking process.

Numerical results of a time history of temperatures at two monitoring points on the painted parts were obtained and compared to the measured data in an actual furnace and showed good agreement. Three types of paints were considered in the present study and numerical results showed different drying characteristics. In addition to the original furnace nozzle configuration, two more furnace nozzle configurations with different numbers, direction and speed of hot air supply were simulated to improve the furnace’s drying performance. As a result, a newly suggested nozzle configuration with quick drying paint can give us a remarkable improvement in surface averaged DOB compared to the original nozzle configuration with original paint.

The present simulation technique and DOB methodology can be used for the optimal design of a drying furnace.

The term “Mental health literacy” is defined as knowledge and beliefs about mental disorders which aid their recognition, management or prevention. The importance of health literacy for physical health is widely studied; however, the area of mental health literacy in Pakistan has been comparatively neglected. The purpose of this paper is to address the knowledge about mental health in people living in Pakistan.

Relevant literature relating to mental health literacy was identified through various database searches. The databases searched included: PubMed, Cochrane database of Systemic Reviews, PsycINFO using the terms mental health, mental health literacy, mental health education, Pakistan.

Literature suggests that there is dearth of knowledge about mental illnesses and their treatment among public. This review also highlights the importance of mental health literacy among professionals working in the field of health care. In Pakistan, due to low literacy rate, a high percentage of poverty and dearth of trained professionals warrants an emendation in approaches established for attaining the goal of public health and psychiatric care.

Findings have implications for practitioners in the field of mental health care as well as designing targeted interventions for enhancing mental health literacy and help-seeking behavior in the future.

A limited understanding and lack of improvement in mental health literacy may interfere with society’s acceptance of evidence-based mental health care which may hamper the delivery of adequate mental health services to the needy.

The commercial and residential refuse generated by Ellsworth Air Force Base, USA was characterized and analyzed for collection procedures, and the opportunities for increasing the amount of solid waste that could be recycled were evaluated.

Random loads of hauled solid waste (an average 3.0 US tons/load) from different waste streams of Ellsworth Air Force Base were sorted. The weight fraction of each category of recyclable material derived from the hand sorting operations was applied to the three years of mixed waste tonnage in order to estimate the tonnage of each recyclable category disposed of as refuse during each year. The assessment of the data obtained from three full calendar years focused on the mixed solid waste generated from commercial and residential areas such as offices, childcare, lodging, supermarkets, food service facilities, and others.

Over 2,500 tones of recycling opportunities were missed during the 1999‐2001 calendar years. The characterizations of the total weight produced from commercial and residential waste streams showed that recyclable material constituted 35.95 percent and 23.27 percent of refuse from the commercial and the residential areas, respectively. The amounts of total recyclable material as missed opportunities for recycling were found to be 1,728 tons and 715 tons from the commercial and residential areas.

In response to the findings, Ellsworth Air Force Base has implemented a number of strategies for increased recovery of recyclables from its solid waste streams.

Quantifying missed opportunities for recycling is a useful action in planning future recycling operations aimed at best solid waste management practices.

This paper aims to provide a historical overview of AA, its purpose and benefits, the legal rationale for the SCOTUS ruling and what it means for colleges and the workplace regarding equitable opportunities for minority groups (which include women, Blacks, Hispanics, Asians and other low-income populations), as they aim for the “American dream”.

SCOTUS decision and rationale, along with literature.

The race-based affirmative action (AA) precedent was recently overturned by the Supreme Court of the United States (SCOTUS) in the case of Students for Fair Admission (SFFA), Inc. vs President and Fellows of Harvard College/University of North Carolina. SCOTUS ruled that race cannot be a specific basis for college admission. In other words, public and private colleges and universities will no longer be able to consider “race” as a factor in deciding which qualified applicants should be admitted to enhance the diversity of their student body.

This is an original analysis.

Drawing on knowledge-based view, social exchange theory and leader-member exchange, this study examines how exploitative leadership (EL) influences knowledge management (KM), its processes, and further investigates the moderating role of organisational citizenship behaviours (OCB) on the relationship between EL and KM.

Using a quantitative approach, survey data were collected from 356 faculty members in Iraqi public universities, and the direct and moderating relationships were assessed through Hierarchical regression by PROCESS v.3.3 macros in SPSS.

The study found a significant negative impact of EL on KM, including its processes, especially on knowledge utilisation. The assessment also revealed that OCB has a significant moderating impact on EL, particularly its effect on knowledge creation.

The empirical insights of the study are valuable and precious for policymakers, managers and academics in education sectors of developing countries, to enrich their managerial and scientific performance through addressing EL behaviours while considering the moderating effect of OCB.

The relevance of the study stems from the scarcity of research on EL, while studies on the negative behaviours of leaders as a predictor of KM process failures are significantly limited. Additionally, studies on the moderating impact of OCB on the linkage between EL and KM processes remain limited. This study is one of the earliest studies that investigate these inter-relationships amongst EL, OCB and KM processes.