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The paper introduces and illustrates the use of numerical models for the simulation of electromagnetic and thermal processes in an absorbing ceramic layer (susceptor) of a new millimeter-wave (MMW) heat exchanger. The purpose of this study is to better understand interaction between the MMW field and the susceptor, choose the composition of the ceramic material and help design the physical prototype of the device.

A simplified version of the heat exchanger comprises a rectangular block of an aluminum nitride (AlN) doped with molybdenum (Mo) that is backed by a thin metal plate and irradiated by a plane MMW. The coupled electromagnetic-thermal problem is solved by the finite-difference time-domain (FDTD) technique implemented in QuickWave. The FDTD model is verified by solving the related electromagnetic problem by the finite element simulator COMSOL Multiphysics. The computation of dissipated power and temperature is based on experimental data on temperature-dependent dielectric constant, loss factor, specific heat and thermal conductivity of the AlN:Mo composite. The non-uniformity of patterns of dissipated power and temperature is quantified via standard-deviation-based metrics.

It is shown that with the power density of the plane wave on the block’s front face of 1.0 W/mm², at 95 GHz, 10 × 10 × 10-mm blocks with Mo = 0.25 – 4% can be heated up to 1,000 °C for 60-100 s depending on Mo content. The uniformity of the temperature field is exceptionally high – in the course of the heating, temperature is evenly distributed through the entire volume and, in particular, on the back surface of the block. The composite producing the highest level of total dissipated power is found to have Mo concentration of approximately 3%.

In the electromagnetic model, the heating of the AlN:Mo samples is characterized by the volumetric patterns of density of dissipated power for the dielectric constant and the loss factor corresponding to different temperatures of the process. The coupled model is run as an iterative procedure in which electromagnetic and thermal material parameters are upgraded in every cell after each heating time step; the process is then represented by a series of thermal patterns showing time evolution of the temperature field.

Determination of practical dimensions of the MMW heat exchanger and identification of material composition of the susceptor that make operations of the device energy efficient in the required temperature regime require and expensive experimentation. Measurement of heat distribution on the ceramic-metal interface is a practically challenging task. The reported model is meant to be a tool assisting in development of the concept and supporting system design of the new MMW heat exchanger.

While exploitation of a finite element model (e.g. in COMSOL Multiphysics environment) of the scenario in question would require excessive computational resources, the reported FDTD model shows operational capabilities of solving the coupled problem in the temperature range from 20°C to 1,000°C within a few hours on a Windows 10 workstation. The model is open for further development to serve in the ongoing support of the system design aiming to ease the related experimental studies.

The purpose of this paper is to examine how active consumers, i.e. consumers that can inter-temporally shift their load, can influence electricity prices. As demonstrated in this paper, inter-temporal load shifting can induce negative electricity prices, a recurring phenomenon on power exchanges.

The paper presents a novel electricity-market model assuming a nodal-pricing, energy-only spot market with active consumers. This study formulates an economic equilibrium problem as a linear program and uses an established six-node case study to compare equilibrium prices of a model with inflexible demand to a model with flexible demand of active consumers.

This study illustrates that temporal coupling of hourly market clearing through load shifting of active consumers can cause negative electricity prices that are not observed in a model with ceteris paribus inflexible demand. In such situations, where compared to the case of inflexible demand more flexibility is available in the system, negative electricity prices signal lower total system costs. These negative prices result from the use of demand flexibility, which, however, cannot be fully exploited due to limited transmission capacities, respectively, loop-flow restrictions.

Literature indicates that negative electricity prices result from lacking flexibility. The results illustrate that active consumers and their additional flexibility can lead to negative electricity prices in temporally coupled markets, which in general contributes to increased system efficiency as well as increased use of renewable energy sources. These findings extend existing research in both the area of energy flexibility and causes for negative electricity prices. Therefore, policymakers should be aware of such (temporal coupling) effects and, e.g. continue to allow negative electricity prices in the future that can serve as investment signals for active consumers.

The purpose of this paper is to discuss a novel life cycle approach to education for sustainable development (ESD) where the students become “design thinkers”.

A case study on the creation, development and utilisation of educational games by university students is presented. The paper discusses the case study in the context of Kolb’s experiential learning and dynamic matching model, Perry’s stages of intellectual development and Beech and Macintosh’s processual learning model. The data used were from questionnaire feedback from the pupils who played the games and students who designed the games. Further qualitative feedback was collected from local schools involved in playing the games created by the students.

Overall, the students responded positively to the assessment and would like to see more of this type of assessment. They enjoyed the creativity involved and the process of developing the games. For the majority of the skill sets measured, most students found that their skills improved slightly. Many students felt that they had learnt a lot about effectively communicating science. The school children involved in playing the student-created games found them accessible with variable degrees of effectiveness as engaging learning tools dependent on the game.

This paper contributes a new approach to ESD which incorporates learner-centred arrangements within a full life cycle of game creation, delivery, playing and back to creation. The games can be used as a tool for enhancing knowledge and influencing behaviours in school children whilst enhancing ESD capacity in schools. The assessment also helps forge important links between the academic and local communities to enhance sustainable development.

The purpose of this paper is to describe a study that explores the discreet activist strategies of educational leaders who promote social justice.

Part of a larger project, this study employed qualitative methods. In particular, researchers interviewed 26 leaders – principals, vice principals, department heads, and central office officials who presided over both homogeneous and diverse schools, departments, and districts in and around a large Canadian city. Data were analyzed during and after data collection, and themes were identified, explored, and described.

Given the resistance they faced in their efforts to promote social justice, leaders found that they had to be strategic in their efforts. In particular, they had to position themselves in ways that reduced their visibility and increased their credibility. When they took action, they tended to adopt subtle rather than obvious strategies.

The harsh reality for activist educational leaders who promote social justice is that they will likely have to be strategic in the way they go about their work. Given the nature of their relationships with the organizations in which they work and the power differentials within which they operate, educational leaders may have to adopt low key or discreet strategies if they are to successfully promote their social justice agendas.

This paper is a regional exploratory study of implicit leadership theories in two regions of China. The purpose of this paper is to compare ideal vs Confucian leadership profiles and explore the possibility of a cultural hybrid perspective of leadership.

This study empirically explores leadership profiles through indigenous leadership research and compares implicit leadership theories of Confucian leadership and ideal leadership among a group of 128 managers representing two regions in mainland China. In doing so, measures developed by Global Leadership and Organizational Behavior Effectiveness that were translated into the local language are employed.

The results empirically show that a region known to have a deeper cultural entrenchment interprets Confucian ideology as ideal leadership, while a region more disconnected from the cultural center transforms its ideology based on more globally accepted leadership ideals.

The findings of this study caution leadership researchers (whether universally-etic or specifically-emic focused) from making generalizations regarding leadership. Although there might be some broad universals of leadership, context-specific leadership practices are deeply rooted between and within cultures.

This paper contributes to the literature by providing insight on implicit leadership theories in China and by proposing a culturally hybrid perspective of leadership based on globalization and cultural entrenchment forces.

In the highly gendered academic sector, womens’ high participation rates have not translated into equal career progression with men. Existing literature suggests that early career publication success is a good indicator of long-term publication success. This research is intended to provide a better understanding of whether the notions of success espoused by neo-liberal universities align with the subjective measures of what constitutes academic success for women ECRs (early career researchers).

The study examines the perceptions of nine successful women ECRs at an Australian university. It uses collaborative autoethnography with thematic analysis of participants’ self-reflective narratives on being a successful ECR.

Five themes were identified. One focussed on objective academic success, which included publications, grants and citations. The other four themes – living a balanced life, making a difference, labour of love and freedom and flexibility – offered more subjective views of success. These included: research making a contribution to society, undertaking research they are passionate about, having autonomy in their role and achieving work-life balance.

The findings demonstrate that women define success in broader terms than neo-liberal universities, and future studies should consider these divergent definitions. Universities committed to equality should understand differences in how women may approach career progress and incorporate this into support processes and in alignment of individual and university goals.

This research offers unique insights into the experience of post-doctoral employment for women in the academic environment and the factors influencing their success in this early career phase.

People spend a lot of time communicating with their co-workers each day; however, research has yet to explore how colleagues influence each other’s health behaviors. The purpose of this paper is to examine the association between health-related communication and health behaviors among co-workers in a workplace wellness program.

Participants (n=169) were recruited from a large south-western university and its local school district through e-mail announcements sent from a wellness administrator. Participants were part of a workplace wellness program that offers several daily group fitness classes, as well as cooking classes, and other educational programs for faculty and staff.

Structural equation modeling was used to examine the association between people’s perceived social influence and social support from co-workers, organizational socialization and their health behaviors. Results indicated that perceived social influence from co-workers had an indirect effect on people’s health behaviors through their perceived social support from their co-workers, as well as through their organizational socialization.

These variables were examined cross-sectionally, meaning that causal relationships and directionality cannot be determined in this study.

Co-worker communication and socialization appear to be important factors in understanding individuals’ health behaviors; thus, organizations that offer workplace wellness programs should provide opportunities for socialization and co-worker communication to facilitate employees’ healthy behaviors.

Although the authors only looked at one wellness program and did not examine these variables in programs of varying sizes and types, this study uniquely incorporates interpersonal and organizational communication perspectives in order to give new insight into co-workers’ health-related communication.

Like it or not, change is inevitable if you are to survive. Far better to instigate change than allow other people to inflict it on you. To anticipate the future has to be good to allow time to implement change rather than having to react to it. This appears quite simple, but is it? This special themed issue of Management Decision contains a number of examples of how organizations have managed change. Lessons can be learned from other industries than your own with regard to best practice and basic principles which can then be applied to your own organization..

This study investigates information quality, information security technology and information sharing with moderation by information security culture and information leakage and how they all play out to influence supply chain performance for contract suppliers (Contract), noncontract suppliers (Noncontract) and pooled suppliers (Contract and Noncontract combined).

Multigroup analysis was deployed to compare the impact on Contract and Noncontract.

The finding on pooled suppliers confirmed the hypothesis that, in the multigroup analysis, information security culture negatively impacted the information quality–information sharing relationship of Contract.

The practical learning point is that Noncontract could still share information and perform and in some instances better than Contract. Noncontract suppliers are still workable.

Information security culture motivated Noncontract to share and perform better than Contract. This result presents a dilemma.

This study aims to first explore the extent to which argumentativeness changed during the adaptation process among Muslim immigrants to France from 2006 to 2015 and, second, to examine the cultural fusion process. The study investigates the influence of intercultural contact on communication traits by exploring the extent to which members of the dominant cultural group adapt their argumentativeness over time.

Through a longitudinal panel study, the paper investigates the influence of intercultural contact on communication traits by exploring the extent to which members of the dominant cultural group adapt their argumentativeness over time. Confirmatory factor analysis and structural equation modeling are used to assess the hypotheses and research question.

Results revealed a curvilinear relationship between argumentativeness and time. Argumentativeness increased from 2006 to 2009, remained constant from 2009 to 2012 and then decreased after 2012. Furthermore, data analysis revealed argumentativeness levels among members of the dominant culture did not change.

The results are potentially limited by the sample being a convenience sample and the presence of extenuating factors.

Argumentativeness is viewed by many researchers as a functional form of communication. However, few studies have longitudinally studied how this trait can change over time.