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The purpose of this paper is to control flow separation over a NACA 4415 airfoil by applying unsteady forces to the separated shear layers using dielectric barrier discharge (DBD) plasma actuators. This novel flow control method is studied under conditions which the airfoil angle of attack is 18°, and Reynolds number based on chord length is 5.5 × 10⁵.

Large eddy simulation of the turbulent flow is used to capture vortical structures through the airfoil wake. Power spectral density analysis of the baseline flow indicates dominant natural frequencies associated with “shear layer mode” and “wake mode.” The wake mode frequency is used simultaneously to excite separated shear layers at both the upper surface and the trailing edge of the airfoil (dual-position excitation), and it is also used singly to excite the upper surface shear layer (single-position excitation).

Based on the results, actuations manipulate the shear layers instabilities and change the wake patterns considerably. It is revealed that in the single-position excitation case, the vortices shed from the upper surface shear layer are more coherent than the dual-position excitation case. The maximum value of lift coefficient and lift-to-drag ratio is achieved, respectively, by single-position excitation as well as dual-position excitation.

The paper contributes to the understanding and progress of DBD plasma actuators for flow control applications. Further, this research could be a beneficial solution for the promising design of advanced low speed flying vehicles.

Pakistan is an agricultural country having the world's largest canal irrigation system. Indus basin that covers 70 percent of irrigated area for crop production is the major source of water in the country. Owing to rapid increase in population and uncertain environmental conditions, this water is not adequate to cope with the crop water requirement and needs additional means to provide extra water for agricultural purposes. The main source of irrigation is canal and ground water but the quality of ground water is so poor for the sustainability of agriculture system. To cope with the present demand, use of municipal sewage water that consists of domestic liquid waste, as well as industrial effluents, is becoming a common practice. The present study aims to reflect the hazardous effects of sewage water on the environment, with the main focus on heavy metals and chemical composition of soil and vegetables.

Industrial effluent was collected from one ghee mill, one flour mill, three textile industries and three hosieries located in Faisalabad, an industrial city of Pakistan highly affected with water pollution. All water samples were analyzed for pH, EC, SAR and RSC. Water analysis was also carried out for various nutrients and heavy metals (K⁺¹, P²⁺, Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺ and Pb²⁺). Soil samples from various depths (0‐15, 15‐30, 30‐60, 60‐90 and 90‐120 cm) were taken to analyze for EC, pH, SAR, Na⁺¹, SO₄, K⁺¹, P²⁺, Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺ and Pb²⁺ after irrigation with canal water and sewage water. Cadmium, lead and copper concentration was determined in various vegetables grown in areas irrigated with canal water and industrial effluents to determine their final concentration in the final product ultimately affecting the human health.

Although the sewage water is a source of many nutrients, it also includes a significant amount of heavy metals like Fe²⁺, Cu²⁺, Zn²⁺, Mn²⁺, Ni²⁺, Pb²⁺ and pathogens. Extensive use of this effluent for irrigation purpose has resulted in an upsurge of such metals in soils and various crops, which ultimately resulted in clinical problems in human beings.

The present study reflects the composition of sewage water and heavy metal accumulation in soil, as well as crops. It further highlights the different potential hazards to humans due to these contaminants.

Aims to extract Rice bran oil (RBO) from Pakistani cultivar Basmati‐385 for efficient use of local rice industrial waste, i.e. rice bran to reduce the import of edible oil and to evaluate the suitability of RBO in baked products by making cookies.

RBO was extracted from stabilized rice bran by solvent extraction. The RBO obtained was analyzed for different quality parameters and further applied into baked products such as cookies at various levels, i.e. 0, 25, 50, 75 and 100 per cent, by gradually replacing normal shortening to check its suitability as a shortening and its effectiveness in extending the shelf life of product due to its natural antioxidants. Five treatments of RBO and normal shortening (NS) (T₁ = 100 per cent NS + 0 per cent RBO, T₂ = 75 per cent NS + 25 per cent RBO, T₃ = 50 per cent NS + 50 per cent RBO, T₄ = 25 per cent NS + 75 per cent RBO and T₅ = 0 per cent NS + 100 per cent RBO) were used to prepare cookies and 45 days, storage study was conducted.

Various treatments and storage have a highly significant effect on moisture, fat and NFE content of cookies. Protein content of cookies remained unaffected by changing treatments. During 45 days, storage moisture, protein, fat and NFE content decreased significantly. Physical studies revealed increase in width and spread factor of cookies, while thickness was reduced, gradually with the proportionate increase of RBO. There was significant decrease in quality score of cookies for color, taste, flavor, crispness, texture and overall acceptability. Treatment T₃ (50 per cent NS + 50 per cent RBO) got the highest score for all the sensory attributes.

The present study suggests that T₃ (50 per cent NS + 50 per cent RBO) can produce superior quality cookies to prove the effectiveness of RBO as bakery shortening.

Although Pakistan is an agricultural country, unfortunately 71 per cent of the country's edible oil requirements are met through the import of edible oil. In the present project the possibility of RBO extraction from local variety was evaluated. In this way, if fully explored, RBO can become the fourth indigenous source of edible oil.

Drawing on Kahn’s model of meaningful connections, this study aims to examine relational attachment as a mediating mechanism linking social support in terms of instrumental support and personal support to employees’ subjective career success.

Data were collected in 2 waves from 247 employees working in Poland. Hypotheses were tested using structural equation modeling in AMOS.

The findings indicated that employees are more attached to and satisfied with their careers when they have a stronger relational attachment to others at work. Furthermore, relational attachment was found to be driven by tangible or intangible instrumental support received at work rather than the personal support received at work.

Managers should recognize the importance of workplace relationships and social support, which can lead to higher career commitment and career satisfaction. However, managers should keep in mind that too much interference in individuals’ privacy and providing too much personal support may lead to adverse outcomes.

The present study expands the scant literature on the mediating role of relational attachment at work between social support received at work and subjective career success.

This study aims to address the timely question of whether Bitcoin exhibited a safe haven property against the major Australian stock indices during the first and second waves of the COVID-19 pandemic in Australia and whether such property is similar or different in one year time from the first wave of the COVID-19.

The authors used the bivariate Dynamic Conditional Correlation, Generalized Autoregressive Conditional Heteroskedasticity model, on the five-day returns of Bitcoin and Australian stock indices for the sample period between 23 April, 2011 and 19 April, 2021.

The results show that Bitcoin offered weak safe haven and hedging benefits when combined in a portfolio with S&P/ASX 200 Financials index, S&P/ASX 200 Banks index or S&P/ASX 300 Banks index. In regard to the S&P/ASX All Ordinaries Gold index, the authors found Bitcoin a risky candidate with inconsistent safe haven and hedging benefits. Against S&P/ASX 50 index, S&P/ASX 200 index and S&P/ASX 300 index, Bitcoin was nothing more than a diversifier. The outset of the second COVID-19 wave, which was comparatively more severe than the first, is also reflected in the results with considerably higher correlations.

There is a lack of in-depth empirical evidence on the safe haven capabilities of Bitcoins for various Australian stock indices during the first and second waves of the COVID-19 pandemic. The study bridges this void in research.

As a result of the so-called information explosion, it is very important for researchers, faculty members and students to access scientific and research information, which highlights the importance of designing university websites. The purpose of this paper was to evaluate Iranian state university websites using the Web quality evaluation method (WebQEM).

The research method was a combination of a descriptive survey and Delphi technique. The research population included 100 Iranian state university websites. Data collection was done using the checklists prepared by WebQEM. Descriptive statistics (frequency, mean and standard deviation) and analysis statistics (Spearman rank-difference correlation coefficient) were used for data analysis.

The results indicated that Iranian state university websites met the four main criteria considered in WebQEM; reliability (mean = 0.67), efficiency (mean = 0.66) and functionality (mean = 0.62) were in a “good” condition, and usability was in a “middle” condition (mean = 0.59). Also, the findings showed that 60 per cent of the websites were in a good condition and 37 per cent were in a middle condition. In conclusion, Iranian state university websites were found to be in a “good” condition (mean = 0.63). Also, Ferdowsi University of Mashhad was ranked in the first place (score = 0.822). The hypothesis that there was a very weak correlation between Iranian state university ranking and Iranian state university websites ranking was confirmed (with the correlation of 0.22).

The paper includes implications for the development of user interface of academic websites. This paper fills a part of the gap in terms of an urgent need for research on how university websites can be standardized. If university websites have significant and necessary standard factors (i.e. ISO 9126-1), students may succeed in academic information retrieval. Using the results of this research can help university website designers to fix weaknesses for active participation in these websites.

This study has evaluated Iranian state university websites using WebQEM.

This study aims to focus on the interpretation component of Peirce’s triadic model of sign to identify: the components affecting the interpretation of an object and the components affecting the meaning creation by people for use in ontologies. Ashura was selected because it is a historical event and a meaningful sign in Iranian religious culture.

This qualitative study was conducted in two steps. In the first step, the Instagram pages of five groups of people were chosen as the sample and examined using qualitative content analysis. In the second step, 18 creators of Ashura works were selected, their lived experience in creating these works was collected using in-depth semi-structured interviews and analysed through phenomenology method.

Based on the results, the concept is context-oriented; one cannot interpret the signs according to one’s personal preferences because the context, social rules and habits limit this interpretation. Accordingly, the use of reference systems and rules of logic, as well as artificial intelligence and computer science tools alone cannot help represent meaning in ontologies. Rather, individual characteristics, contexts, presuppositions and components existing in personal, social and technological worlds are effective on concept formation and meaning creation. Thus, these factors must be considered in ontology, especially for multi-faceted and context-oriented concepts, such as Ashura.

This research adopted a new approach and method to study ontology. This study focused on interpretation and adopted Peirce’s sign model for ontology design.

The purpose of this paper is to discuss the importance of mission and vision in the process of state development. Using the case of Pakistan, it will be argued that state organizations do not develop and find the right direction without outlining a clear mission and vision which will be beneficial to all citizens, who are the real stakeholders.

Yin (2003) and Baxter and Jack (2008) argue that case study is an enriched method to explore a complex relationship. The complex relationship may be understood better by qualitative methods than quantitative. Following their suggestion, case study method will be adopted to understand the relationship between the mission and vision and state development. In this study, Pakistan will be used as a case. Moreover, the technique of historical analysis will be employed to understand this relationship. Historical analysis is important because the repercussions of current actions can only be evaluated in the future.

The paper shows the importance of “mission and vision” for state development. Using Pakistan as the case, it is argued that a state can lose its direction without having a clear mission and vision. It is further contended that it is not erection of institutions or verbal/written pronouncements and slogans, but a strong commitment to the mission and the vision brings the required change, which helps to develop a state. In the future research, the researcher can further examine the role of mission and vision in relation to state development.

The limitation of this study is that it has only focussed on the leadership and politics of Pakistan. In the future, a comparative study investigation may be useful.

The research is useful for political leaders, political scientists and public management researchers.

The research is unique and original that it evaluates the role of leadership and the development of the state from the perspective of mission and vision, which has not been done in the earlier research. Moreover, the paper elaborates the concept of state development.

The inappropriate lighting methods can have irreversible effects on artworks available in museums and exhibitions. Several factors affect the choice of the lighting system in the museums. By surveying all possible elements, this paper aims to propose a sustainability-based solution, as it relates to the development of artwork conservation, visual perception and energy efficiency during operation and maintenance (O&M).

The paper elicits optimal solutions out of the method presented based on functions and expert opinion to improve lighting quality in existing museums. To study the optimization, the energy consumption and life cycle cost (LCC) in both the proposed lighting and the existing lighting system are compared using HoneyBee and LadyBug plugins in GrassHopper, as well as BLCC5 energy cost estimation software.

The results indicated a practical method to select the most suitable solution for museum lighting. By applying the proposed solutions obtained from the case study, a significant reduction in energy consumption and LCC were achieved. Besides, greenhouse gases were remarkably decreased.

Providing the proper lighting systems for each museum is the issue that is given special attention during the facilities management. The quality of the lighting, energy consumption and costs are analyzed by the simulation software. It is recommended that the validity considerations of the practice are examined.

The present study tried to present an optimal method to choose the best lighting system by the simultaneous utilization of theoretical and practical aspects. The functional model is also introduced for performing the most effective method to enhance the lighting techniques in the art museums.

Debates regarding climate change risk perception (CCRP), particularly its scale and impact on social and environmental sustainability, have continued for decades. CCRP is experiencing a renaissance with an increased focus on environmentally relevant behaviors to mitigate the effects of climate change. However, CCRP lacks investigation from the employee perspective. Supported by the social exchange and value–belief–norm theories, this study aims to address the impact of employees’ CCRP on their proenvironmental behavior (PEB) via the moderating roles of environmental values and psychological contract breach.

The nonprobability convenience sampling technique was used to collect survey data from a sample of 299 employees across 138 manufacturing firms in Pakistan.

The results show that employees’ CCRP positively impacts their PEB and that this relationship is moderated by their environmental values and psychological contract breach. Specifically, environmental values strengthen the CCRP–PEB relationship, while psychological contract breach weakens it.

The findings of the study emphasize useful guidance for managers and practitioners as a future avenue to restructure the climate change framework by emphasizing the conditions (i.e. environmental values and psychological contract breach). In doing so, the study is beneficial for managers and practitioners in helping to increase employees’ PEB through the development of climate change action plans.

To the best of the authors’ knowledge, this study is one of the first investigations into CCRP–employees’ PEB nexus in the developing country context. The study incorporates social exchange and value–belief–norm theory, which serve as the CCRP’s theoretical underpinnings. The findings advance the new knowledge about a firm’s social responsibility to achieve the sustainable development goals outlined in the UN’s 2030 Agenda.