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Pumped-storage hydroelectricity (PSH) is considered as an effective method to moderate the difference in demand and supply of electricity. This study aims to understanding of the high capacity of energy production, storage and permanent exploitation has been the prominent feature of pumped-storage hydroelectricity.

In this paper, the optimization of energy production and maintenance costs in one of the large Iranian PSH has been discussed. Hence, a mathematical model mixed integer nonlinear programming developed in this area. Minimizing the difference in supply and demand in the energy production network to multiple energies has been exploited to optimal attainment scheme. To evaluate the model, exact solution CPLEX and to solve the proposed programming model, the efficient metaheuristics are utilized by the tuned parameters achieved from the Taguchi approach. Further analysis of the parameters of the problem is conducted to verify the model behavior in various test problems.

The results of this paper have shown that the meta-heuristic algorithm has been done in a suitable time, despite the approximation of the optimal answer, and the consequences of research indicate that the model proposed in the studied power plant is applicable.

In pumped-storage hydroelectricity plants, one of the main challenges in energy production issues is the development of production, maintenance and repair scheduling concepts that improves plant efficiency. To evaluate the mathematical model presented, exact solution CPLEX and to solve the proposed bi-objective mixed-integer linear programming model, set of efficient metaheuristics are used. Therefore, according to the level of optimization performed in the case study, it has caused the improvement of planning by 7%–12% and effective optimization processes.

The aim of this paper is to predict and minimize the risks of oil, gas and petrochemical projects. Besides, reducing the likelihood of occurrence and minimizing risks impact on the projects to reduce the probable costs and improve the economic situation is another purpose of this paper.

This paper provides a fuzzy Decision-Making Trial and Evaluation Laboratory (DEMATEL) – a technique that assist to solve decision-making problems – and IP (Impact & Probability) table methods to identify and analyze critical risks in energy projects, and then fuzzy Binary Logistic Regression (BLR) in order to predict the probability of each level of risk for more efficient risk management in projects. Furthermore, in this paper, the fuzzy BLR (FBLR) is optimized such that the probability of a high level of risk for the implementation of the project has been minimized using meta-heuristic algorithm.

The results from the point of view of experts show that combination of fuzzy DEMATEL with FBLR approach as well as using SA algorithm, in order to optimize the high level of risks, can provide a smart approach to managing risks with more success.

The application of the proposed method is illustrated via a real data set from energy projects.

We propose combined fuzzy DEMATEL and FBLR methods to predict and optimize the risks of the energy projects, which is the innovation of this paper.

International alliances are becoming an increasingly important and recognized means of conducting business. Once viewed primarily as a strategy to enter foreign markets, alliances have become a very effective way for established businesses to accelerate technological development, enhance productivity and lower investment risks. In many ways joint ventures offer the most attractive form of trade alliance and a significant portion of the international joint ventures are in the service sector. Although, services are generally viewed by academicians and practitioners differently than products, this apparent difference has been neglected in the study of joint ventures formation and operations. Since the basic conditions and scope for services and products differ, one can expect that joint venture partners' interest and management strategies for service joint venture will also differ. Thus, the purpose of this study is to discuss and identify major research issues in studying service joint ventures. Some research propositions in regard to the service joint ventures are developed. Furthermore, future research avenues in international service joint venture operations are delineated.

Purpose: The main purpose of this study is to test the effect of consumers’ readiness level to use new technology on their intention to use mobile payment applications based on the technology readiness and acceptance model (TRAM). In detail, it examines how the dimensions of TR as ‘optimism, innovativeness, discomfort, and insecurity’ affect consumers’ intention to utilise mobile payment applications. Moreover, the effect of the technology-accepting behaviour measured by two major factors as ‘perceived usefulness’ and ‘perceived ease of use’ on the intention to use mobile payment applications is also examined.

Need for the study: The existence of a mobile system alone is not enough to attract consumers with no user experience to these applications. The user-centred attribute in the usage of these applications, which involves the influence of technology readiness (TR), has been largely ignored especially in developing countries. By focussing on this area, it is expected to fill the gap that has not been sufficiently handled in the developing country settings and, particularly in Turkey.

Methodology: The study population consists of the consumers who live in İstanbul who is aged 18 and over and use mobile payment technology at least once. After collecting data, confirmatory factor analysis was applied to validate the measurement model. Afterward, the structural model was tested by the Maximum Likelihood-MI estimation method, and the bootstrap samples were stated as 5,000.

Findings: When the results of the study are examined, it is seen that optimism has a significant influence on the perceived usefulness and perceived ease of use dimensions of the technology acceptance model, while innovativeness is significant only on the perceived ease of use. This study results also show that discomfort and insecurity don’t significantly influence the perception of usefulness and easy-to-use mobile payment applications as perceived by individuals. Perceived ease of use is to positively affect the perceived usefulness. Additionally, the perceived ease of use and the perceived usefulness are strong predictors of intention to use mobile payment applications.

Practical implications: Findings of this study demonstrate the validity of the technology readiness and acceptance model for explaining the intention of using mobile payment applications in Turkey. To improve consumers’ intent in the usage of m-payment apps, their level of technological readiness towards technology should be determined and the factors that affect the formation of insecurity and discomfort attitudes of individuals should be emphasised.

The focus of this paper is a comparative case study of the symbolic role of the Croatian and Serbian languages and writing in discourses of the Nation and the National. Our research is situated at the intersection of the scientific fields of sociolinguistics, memory studies, and studies on nationalism. Using Anthony D. Smith’s ethno-symbolist approach to the study of nationalism, which focuses on the reciprocal relationship between elites and the people, we analyze the case of anti-Cyrillic protests in Vukovar, Croatia, which were triggered by the implementation of Croatian minority rights legislation. This research analyses the role of language and its use as a symbol in memory practices and accompanying discourses in Croatia and its echoes in Serbian public space. The top-down perspective observes state-promoted events and populist implications of language mis(use). Alternatively, the bottom-up approach encompasses various actions and initiatives of so-called “activists” who belong either to “nationalist” organizations or to liberal/democratic NGOs. The majority of voices that are not aligned with the above-mentioned organizations are neglected in the public space (Obradovic-Wochnik, 2013).

We explore the dynamics created between social groups promoting populist ideas, other groups promoting alternative practices, and their influence on the ideological pattern adopted by ruling elites.

The purpose of this paper is to examine the influence of personality traits on the perception of key message characteristics in road safety advertising.

The advertisement uses visual imagery and imagery methods to examine key message characteristics. An online survey questionnaire was used to obtain responses of 947 driver perceptions with various personality traits; and the data are explored using multiple linear-regressions.

The findings of the research indicate the importance of using key message characteristics based upon established scientific theory to developing messages, more particularly in road safety and other social marketing campaigns. The role of personality traits and its relevance also appear to be of primary importance and can be used to segment the market; guide message designs and development, as different personality traits are found to be significant for different message characteristics.

This research varies from preceding efforts as it examines the influence of personality traits on drivers’ perceptions of messages using established scientific theory, and bridging the gap in the research between two main paths of research with reference to fear-based messages: the process that influences an individual response to key messages; and the influences of personality trait differences on message perceptions.

This study extends the knowledge in several essential areas and offers a set of recommendations to assist marketers in developing effective message strategies and segmentation based on personality traits. Besides advancing theory, this study enhances the understanding of how to develop more effective road safety messages that will save lives and prevent injuries.

The present work aims to formulate nanolubricants and improve antiwear, antifriction and extreme pressure (EP) performances of castor oil (CO) with surface-modified CuO nanoparticles as an additive in the boundary lubrication regime.

In this study, CuO nanoparticles are modified with a surfactant sodium dodecyl sulfate (SDS) by means of a chemical method. These modified nanoparticles with varying concentrations of 0.1, 0.25, 0.5 and 1.0%w/v were used to formulate the nanolubricants. The tribological properties of non-formulated and formulated CO were examined using a four-ball tester. The tribological test results were compared with paraffin oil (PO) for similar compositions.

The nanoparticle concentrations in base oils were optimized by wear scar diameter (WSD) and load carrying capacity during antiwear and EP tests, respectively. In the antiwear test, the maximum reductions in WSD were 28.3 and 22.2 per cent; however, the coefficient of friction was reduced by 34.6 and 17.3 per cent at optimum nanoparticle concentrations in CO and PO, respectively. A significant improvement in the weld load was observed for both nanolubricants.

This work indicates that nanoparticle-based CO in industrial applications provides on par or better results than mineral oil. Also, it has a negligible hazardous impact on our eco-system.

This paper aims that mobile health (mHealth) applications have emerged as a key tool to support public health. However, there are only a few studies examining the influences of health-related ascribes on continuance intention to use mHealth apps and how these influences are contingent on gender in the mHealth app using context.

This study takes the protection motivation theory as a theoretical framework to examine the ordered relationship between threat and coping appraisals and their impacts on continuance intention to use mHealth apps. In addition, this study further extends the literature on gender differences into the mHealth app's context to investigate the moderating role of gender. The suggested hypotheses are confirmed by a structural equation modeling approach and multigroup investigation employing survey data of 345 users of Spring Rain Doctor in China, a typical mHealth app.

The findings suggest that the impact of perceived disease threat on user's continuance intention is mediated entirely by coping appraisals. Furthermore, the three coping appraisals' impacts are contingent upon gender. Specifically, response efficacy is more crucial for male users in forecasting continuance intention, whereas self-efficacy and response cost have a more salient influence on continuance intention for female users.

This study examines the ordered influences of threat and coping appraisal, moderated by gender, on continuance intention on use mHealth apps. These findings could contribute to relevant theoretical and practical implications.

This study aims to identify the counterproductive knowledge behavior (CKB) of volunteers in nonprofit organizations and its influencing factors, based on the theories of planned behavior and well-being.

An online survey was used to collect 496 valid responses. A structural equation model was constructed, and the relationships among the constructs were estimated via the maximum likelihood method. To analyze the direct and indirect effects, 2,000 bootstrapping runs were conducted. A Kruskal-Wallis test was also conducted to analyze the relationship between the variables.

A combination of organizational factors and individual attitudes and perceptions can be used to explain CKB. Insecurity about knowledge sharing had the greatest impact on CKB. A competitive organizational norm induced CKB while a knowledge-sharing organizational norm did not have a significant impact. Further, the more self-determined the volunteer activity was, the more the CKB was suppressed. However, well-being did not have a significant direct effect. Volunteers with high levels of well-being and self-determination had significantly lower levels of insecurity about knowledge sharing compared to those who did not.

Well-being arising from volunteering did not directly suppress CKB. To improve organizational efficiency by reducing CKB, nonprofit organization managers should provide intrinsically motivating tasks and interact with the volunteers.

There is a lack of empirical research on CKB in volunteer organizations; therefore, the authors propose a new approach to knowledge management in volunteer activities.