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The purpose of this paper is to study the effect of piston position on the in-cylinder swirling flow in a simplified model of a large two-stroke marine diesel engine.

Large eddy simulations with four different models for the turbulent flow are used: a one-equation model, a dynamic one-equation model, a localized dynamic one-equation model and a mixed-scale model. Simulations are carried out for two different geometries corresponding to 100 and 50 percent open scavenge ports.

It is found that the mean tangential profile inside the cylinder changes qualitatively with port closure from a Lamb-Oseen vortex profile to a solid body rotation, while the axial velocity changes from a wake-like profile to a jet-like profile. The numerical results are compared with particle image velocimetry measurements, and in general, the authors find a good agreement.

Considering the complexity of the real engine, the authors designed the engine model using the simplest configuration possible. The setup contains no moving parts, the combustion is neglected and the exhaust valve is discarded.

Studying the flow in a simplified engine model, the setup allows studies of fundamental aspects of swirling flow in a uniform scavenged engine. Comparing the four turbulence models, the local dynamic one-equation model is found to give the best agreement with the experimental results.

The purpose of this paper is to present large‐scale parallel direct numerical simulations of granular flow, using a novel, portable software program for discrete element method (DEM) simulations.

Since particle methods provide a unifying framework for both discrete and continuous systems, the program is based on the parallel particle mesh (PPM) library, which has already been demonstrated to provide transparent parallelization and state‐of‐the‐art parallel efficiency using particle methods for continuous systems.

By adapting PPM to discrete systems, results are reported from three‐dimensional simulations of a sand avalanche down an inclined plane.

The paper demonstrates the parallel performance and scalability of the new simulation program using up to 122 million particles on 192 processors, employing adaptive domain decomposition and load balancing techniques.

Two-phase R-744 ejectors are critical components enabling energy recovery in R-744 heat pump and refrigeration systems, but despite their simple geometry, the flow physics involve complex multiphase mixing phenomena that need to be well-quantified for component and overall system improvement. This study aims to report on multiphase mixture simulations for a specific two-phase R-744 ejector with supercritical inlet conditions at the motive inlet side.

Four different operating conditions, which have motive inlet pressure range of 90.1 bar–101.1 bar, are selected from an existing experimental data set. A two-phase thermodynamic equilibrium (TPTE) model is used, where the fluid properties are described by a thermodynamic look-up table.

The results show that the TPTE model overpredicts mass flow rates at the motive inlet, resulting in a relative error ranging from 15.6% to 21.7%. For the mass flow rate at the suction inlet, the relative errors are found less than 1.5% for three cases, while the last case has an error of 12.4%. The maximum deviation of the mass entrainment ratio is found to be 8.0% between the TPTE model and the experimental data. Ejector efficiency ranges from 25.4% to 28.0%. A higher pressure difference between the ejector outlet and the diverging nozzle exit provides greater pressure lift.

Based on the results, near future efforts will be to optimize estimation errors while enabling more detailed field analysis of pressure, density, temperature and enthalpy in the computational domain.

The authors have two main original contributions: 1) the presented thermodynamic look-up table is unique and provides unique computation for the real-scale ejector domain. It was created by the authors and has not been applied before as far as we know. 2) To the best of the authors’ knowledge, this study is the first study that applies the STAR-CCM+ multiphase mixture model for R-744 mixture phenomena in heat pumps and refrigeration systems.

This paper proposes and tests a model to explain the outcomes of three different information presentation formats. Based on cognitive fit theory, information visualization formats that best fit task characteristics are expected to lead to improved decision-making outcomes. We apply the Judgment and Decision-Making framework (Bonner, 2008) to investigate how certain factors can impact decision quality.

This study tests whether certain production variance presentation formats (percentages, dollar amounts, and schematic faces), task complexity, understanding of the presentation format, motivation, and effort increase the accuracy of a supervisor’s bonus calculation. A total of 281 students and professionals participated in this experiment. Their responses were examined using regression analysis.

Our results indicate that individuals mostly prefer the percentages presentation format and that the use of the percentages presentation format, a lower level of task complexity, and a better understanding of the variance presentation format lead to more accurate calculations in the experimental task.

Our study provides a call for further research on factors that influence the choice of presentation format as a potentially fruitful area for management accounting researchers.

We exhort practicing management accountants to exert direct influence on employees’ decision making through the use of variance presentation formats that fit their tasks and promote understanding.

Our experiment introduced two major innovations: it uses an interactive data visualization approach allowing subjects to select their preferred presentation format; and it focuses on production variances, a topic that has received less attention in the academic managerial accounting literature, but is still very relevant to practitioners.

The purpose of this study is to explore whether pension plan reporting readability affects earnings volatility. Moreover, as SFAS 158 requires firms to fully recognize their funded status on the balance sheet, the firms’ pension liabilities (inside debts) and financing ability have the corresponding change. This study further investigates whether pension plan reporting readability affects earnings volatility from the SFAS 158 and funded status perspectives.

This study follows Li (2008), Lehavy et al. (2011) and Rennekamp (2012) to use the FOG and SMOG variables as the readability proxies and investigates whether pension plan reporting readability affects earnings volatility from the perspectives of inside debts and SFAS 158 by using a sample of 3,077 American firms from the year 2006 to 2009.

Empirical results of this study show that firms with low readability of pension plan reporting have high earnings volatility, revealing that less readable pension plan reporting increases the assessed variance of a firm’s inside debts, financing flexibility, investment ability and therefore profitability. In addition, the implement of SFAS 158 enhances the effect of pension plan reporting readability on earnings volatility. Moreover, the authors also find that the funded status plays a moderating role for the effect of pension plan reporting readability on earnings volatility. Finally, the results are robust to endogeneity issue.

Earnings stability measures how consistently earnings have been generated over time, and its importance has been acknowledged by most firms. For example, prior literature has documented that manipulating financial reporting to smooth earnings is becoming a business common practice (Burgstahler et al., 2006; Liu and Espahbodi, 2014). The empirical results suggest that pension plan reporting readability is a significant determinant of earnings volatility.

As a practical implication, this study points out that manipulations of the pension reporting readability are not costless. It incurs the costs of earnings instability.

This study indicates that the issuance of SFAS 158 makes firms more likely to engage in pension plan readability manipulation. As a result, it has policy implication that the regulator should consider how the policy change alters the firm financial reporting behavior.

The empirical results suggest that firms may be more likely to engage in obfuscating pension plan disclosure after FASB’s issuance of SFAS 158. This would further increase outside investors’ assessed variance for inside debts and earnings volatilities. When policymakers require firms to recognize their funded status in statement of financial position, they should consider the costs or benefits that the firm manager face and, therefore, how this policy change alter the firm financial reporting behavior.

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).

This study aims to reflect on quality, sustainability and resilience as emerging organisational priorities within total quality management (TQM) and organisational excellence.

The paper uses a conceptual approach based on reflection and theoretical studies on the philosophical foundations of quality, excellence, resilience and sustainability as cornerstones for organisational excellence. Bearing in mind that sustainable excellence rests upon a combination of systemic and soft issues that define organisational ability for resilience and sustainability, there is a need to analyse and reflect on short business cases from world-leading companies and further reflect on the fundamental principles, which have helped such companies to survive, grow and sustain. This study includes such a business case – the LEGO case. In addition, a Japanese case has been included. Japanese training material on human motivation developed in the 1980s exemplifies how company managers were trained, at that time, to understand and practice human motivation, excellence principles and tools.

Organisational excellence constitutes an evolving concept as the world becomes more chaotic and interconnected with multiple disruptive shocks. Organisational excellence challenges the inflexibilities of Newtonian mindsets, recognising the paramount importance of interactions and further underlining the significance of invisible elements such as human potentiality, motivation and values that formulate the principles of organisational excellence.

The paper investigates the notions of quality, resilience and sustainability and their relation to motivation and organisational excellence within the framework of business management and TQM. A world-leading company – LEGO – will be used to exemplify the theoretical findings together with the Japanese Motivation Training Programme case.

Thirty-two qualitative research reports on co-teaching in inclusive classrooms, identified through a comprehensive literature search, are reviewed. Studies have included significant diversity in grade level, geographical location, setting, and took place in three different countries. Overall, teachers and administrators reported a high degree of satisfaction with co-teaching. However, a number of needs were also addressed, including administrative support, appropriate caseloads, planning time, student skill level, and co-teacher compatibility. Implications for research and practice are discussed.

Proposes that multinational companies (MNCs) establish virtual communities of practice, i.e. intranet‐based collaborative forums, and thereby benefit from a combination of codification and personification strategies in order to solve knowledge retrieval problems for the knowledge worker.

Based on an overview of the problems related to retrieval (i.e. individual decoding and interpretation of knowledge), a literature review on individual memory, databases, social capital and virtual communities of practice reveals a knowledge retrieval means matrix, paying respect to retrieval processes.

Virtual communities of practice are suggested as a strategy for internationally‐operating corporations that cannot develop regular face‐to‐face contact between employees, but still need some degree of personification for efficient knowledge transfers.

Being a conceptual paper, quantitative/qualitative integration will enrich the debate further. Also, the very narrow focus on firms' information systems excludes important aspects such as knowledge creation, transfer stickiness, and application of retrieved knowledge.

The knowledge retrieval means matrix is a useful instrument for managers to map and further develop their organizations for better utilization of the organizational memory.

The combined tripartition of virtual communities, the combination of codification and personalization, and knowledge retrieval is, to the best of the authors' knowledge, presented for the first time.

The purpose of this paper is to elaborate a multi‐criteria methodology for the performance assessment of energy supply technologies, which also takes into account the dynamics of technological change.

The approach chosen is based on the multi‐criteria outranking methodology Preference Ranking Organisation METHod for Enrichment Evaluations (PROMETHEE), which is linked to the concept of technology's life cycle by assigning criteria weights depending on the actual development phase of a certain technology. The modifications to the PROMETHEE algorithm are described and the modified methodology is demonstrated by evaluating heat and power supply alternatives for a municipal area in Germany.

The methodology is suitable for the evaluation of energy technologies taking into account varying preferences depending on their stage of maturity. It is a feasible alternative to other methodologies which allow for interconnections like the analytic network process. The results show that, based on a multi‐criteria life cycle approach, renewable energy technologies are competitive with conventional alternatives for supplying heat and power.

Appropriate methods are required to elicit life cycle‐dependent preferences. Decision support should help decision makers (DMs) to articulate preferences according to different development phases and illustrate the results in the most meaningful way.

The methodology provides the basis for a comprehensive analysis of energy technologies at different life cycle stages. It can be used to support decision making in different situations and by various actors.