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This paper reports on the development of a repulsive type magnetic bearing system and the importance of permanent magnet (PM) configuration on the attenuation of radial disturbance. A new configuration of the permanent magnet of the bearing system resulting in improved stiffness characteristics in the radial direction has been described. Prototype models have been designed and developed in our laboratory and experiments carried out.

An automatic query expansion (AQE) facility in an online catalogue was evaluated in an operational library setting. The Okapi experimental system had other features including: ranked output ‘best match’ keyword searching, automatic stemming, spelling normalisation and cross referencing as well as relevance feedback. A combination of transaction log analysis, search replays, questionnaires and interviews was used for data collection. Findings show that contrary to previous results, AQE was beneficial in a substantial number of searches. User intentions, the effectiveness of the ‘best match’ search and user interaction were identified as the main factors affecting the take‐up of the query expansion facility.

This paper aims to present the methodology for designing a system providing comprehensive data about the UK’s museums and enabling research into the history, status and long-term development of the entire sector.

The authors have devised and applied an iterative methodology to deliver a knowledge base, web application and website through which these and related resources are publicly accessed, allowing incorporation of the requirements of user stakeholders drawn from across the UK museum sector.

The methodology has enabled the elicitation of usage scenarios, research questions and feedback from a broad range of user stakeholders, allowing the system to be successfully delivered within the time and staffing constraints of a single publicly-funded research project. Feedback received from external evaluators and users of the system has been overwhelmingly positive.

The system includes the only comprehensive data set of the UK’s museums and is enabling new research by museum studies scholars and museum professionals. The methodology can inform other projects aiming to create specialist knowledge resources involving a wide range of user stakeholders, particularly within constrained time and staffing resources.

This chapter investigates how night-time light images acquired from the Defense Meteorological Satellite Program’s Operational Linescan System provide spatial and temporal insight into the economic impact of the disintegration of Yugoslavia. First, the chapter provides an overview of the economic development in Yugoslavia using conventional statistics, and second, it presents an analysis of the disintegration of the federation by comparing official statistics with night-time light data. Evaluating the impact of the disintegration of Yugoslavia as a federation and the conflicts arising in the wake of the break up is challenging since reliable data is missing. Therefore, satellite images, as one of the few sources of objective information, are potentially of great importance. We used yearly Operational Linescan System composites covering the period 1992–2013. The analysis is divided into small geographical units (districts) based on the republics in the former Yugoslavia.

This study aims to thoroughly examine the milling process applied to fused filament fabrication (FFF) parts. The primary objective is to identify the key variables in creating smooth surfaces on FFF specimens and establish trends about specific parameters.

In this study, PLA and ABS samples fabricated by FFF are subjected to side milling in several experiments. Achievable surface quality is studied in relation to material properties, milling parameters, tooling and macrostructure. The surface finish is quantified using profile measurements of the processed surfaces. The study classifies the created chips into categories that can be used as criteria for the anticipated quality. Spectral analysis is used to examine the various surface formation modes. Thermal monitoring is used to track chip formation and surface temperature changes during the milling process.

This study reveals that effective heat dissipation through proper chip formation is vital for maintaining high surface quality. Recommended methodology demands using a tool with a substantial flute volume, using high positive rake and clearance angles and optimizing the feed-per-tooth and cutting speed. Disregarding these guidelines may cause the surface temperature to surpass the material’s glass transition, resulting in inferior quality characterized by viscous folding. For FFF thermoplastics, optimal milling can bring the average surface roughness down to the micron level.

This research contributes to the field by providing valuable guidance for achieving superior results in milling FFF parts. This study includes a concise summary of the theoretically relevant insights, presents verification of the key factors by qualitative analysis and offers optimal milling parameters for 3D-printed thermoplastics based on systematic experiments.

The purpose of this paper is to investigate numerically thermal convection heat transfer in closed square and cubical cavities with local energy sources of various geometric shapes.

The analyzed regions are square and cubical cavities with two isothermally cold opposite vertical walls, whereas other walls are adiabatic. A local energy element of rectangular, trapezoidal or triangular shape is placed on the lower surface of the cabinet. The lattice Boltzmann technique has been used as the main method for the problem solution in two-dimensional (2D) and three-dimensional (3D) formulations, whereas the finite difference technique with non-primitive parameters such as stream function and vorticity has been also used.

The velocity and temperature fields for a huge range of Rayleigh number 104–106, as well as for various geometry shapes of the heater have been studied. A comparative analysis of the results obtained on the basis of two numerical techniques for 2D and 3D formulations has been performed. The dependences of the energy transfer strength in the region on the shape of energy source and Rayleigh number have been established. It has been revealed that the triangular shape of the energy source corresponds to the maximum values of the velocity vector and temperature within the cavity, and the rectangular shape corresponds to the minimum values of these mentioned variables. With the growth of the Rayleigh number, the difference in the values of these mentioned variables for rectangular and triangular shapes of heaters also increases.

The originality of this work is to scrutinize the lattice Boltzmann method and finite difference method for the problem of natural convection in 2D and 3D closed chambers with a local heated element.

The purpose of this paper is to highlight the need for degradation data in order to improve the reliability and the mean residual life estimation of a specific item of equipment and to adapt the preventive maintenance tasks accordingly.

An initial reliability model which uses a degradation-based reliability model that is built from the collection of hitting times of a failure threshold. The proposed maintenance model is based on the cost/availability criterion. The estimation of both reliability and optimum time for preventive maintenance are updated with all new degradation data that are collected during operating time.

An improvement for the occurrences of maintenance tasks which minimizes the mean cost per unit of time and increases the availability.

Inspection tasks to measure the degradation level should be realized at least one time for each item of equipment at a specific time determined by the proposed methodology.

The introduction of a criterion which helps the maintainer to decide to postpone or not the preventive replacement time depending on the measured degradation level of a specific item of equipment.

The paper complements the research framework proposed by Kim and Matsumura (2017) through a broad survey of the management accounting research in sustainability.

The paper reviews recent management accounting research in the area of corporate responsibility/sustainability; focusing on articles published in seven widely recognized accounting journals and the Journal of Business Ethics.

Our survey of the recent literature indicates: (1) a major focus has been on integration of sustainability in management control systems; (2) the primary research methods used are case studies and surveys, with few large sample, archival studies (primarily on compensation); and (3) a significant amount of literature has been published outside of the traditional accounting literature.

The paper complements existing literature reviews in the area by focusing on the set of most widely recognized journals. By focusing on these journals, we highlight opportunities for future research that are likely to reach a broader accounting readership.

This paper aims to empirically examine the long- and short-run relationship between macroeconomic indicators (exchange rates, interest rates, exports, imports, foreign reserves and the rate of inflation) and sovereign credit default swap (SCDS) spreads for Pakistan.

The authors apply the autoregressive distributed lag (ARDL) model to explore the level relationship between the macroeconomic variables and SCDS spreads. The error correction model is estimated to examine the short-run effects of the underlying macroeconomic variables on SCDS spreads. Finally, the long-run estimates are obtained in the ARDL framework. The study uses monthly data covering the period January 2001-February 2015.

The results indicate that there is a significant long-run relationship between the macroeconomic indicators and SCDS spreads. The estimated long-run coefficients reveal that both the interest rate and foreign exchange reserves are significantly and negatively, whereas imports and the rate of inflation are positively related to SCDS spreads. Yet, the results suggest that the exchange rate and exports do not have any significant long-run impact on SCDS spreads. The findings regarding the short-run relationship indicate that the exchange rate, imports and the rate of inflation are positively, whereas the interest rate and exports are negatively related to SCDS spreads.

The results suggest that State Bank of Pakistan should design monetary and foreign exchange rate polices to minimize unwanted variations in the exchange rate to reduce SCDS spreads. The results also suggest that it is incumbent to Pakistan Government to improve the balance of payments to reduce SCDS spreads. The findings also suggest that the inflation targeting policy can also help in reducing SCDS spreads.

This is the first study to examine the empirical determinants of SCDS spreads for Pakistan. Second, it estimates the short- and long-run effects in the ARDL framework. Third, it considers both internal and external empirical determinants of SCDS spreads.

This research uses a firm’s disclosure of climate risk index derived from deep learning analysis of earnings conference calls to investigate how these disclosures affect market reactions among publicly traded European companies. To address potential endogeneity issues, the study employs an event study methodology, using the Paris Agreement as an exogenous shock that signalled a stronger global commitment to climate action.

Apart from the standard ordinary least squares regression analysis, several robustness tests are used to ensure the validity and reliability of the results. These tests include propensity score matching, entropy balancing, and instrumental-variable analysis. Our final sample comprises 439 observations from European countries.

Our research shows that a firm’s greater exposure to climate risk causes the market to react negatively to the event. This suggests that regulatory scrutiny may raise costs for the company, which could ultimately result in lower stock returns.

Using a unique climate risk disclosure metric based on textual analysis in a European context, our study is the first to investigate the impact of firm-level climate risk disclosure on shareholder wealth.