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The purpose of this paper is to investigate an alternative to established hysteresis models.

Different mathematical representations of the magnetic hysteresis are compared and some differences are briefly discussed. After this, the application of the T(x) function is presented and an inductor model is developed. Implementation details of the used transient circuit simulator code are further discussed. From real measurement results, parameters for the model are extracted. The results of the final simulation are finally discussed and compared to measurements.

The T(x) function possesses a fast mathematical formulation with very good accuracy. It is shown that this formulation is very well suited for an implementation in transient circuit simulator codes. Simulation results using the developed model are in very good agreement with measurements.

For the purpose of this paper, only soft magnetic materials were considered. However, literature suggests, that the T(x) function can be extended to hard magnetic materials. Investigations on this topic are considered as future work.

While the mathematical background of the T(x) function is very well presented in the referenced papers, the application in a model of a real device is not very well discussed yet. The presented paper is directly applicable to typical problems in the field of power electronics.

Medical research requires biological material and data collected through biobanks in reliable processes with quality assurance. Medical studies based on data with unknown or questionable quality are useless or even dangerous, as evidenced by recent examples of withdrawn studies. Medical data sets consist of highly sensitive personal data, which has to be protected carefully and is available for research only after the approval of ethics committees. The purpose of this research is to propose an architecture to support researchers to efficiently and effectively identify relevant collections of material and data with documented quality for their research projects while observing strict privacy rules.

Following a design science approach, this paper develops a conceptual model for capturing and relating metadata of medical data in biobanks to support medical research.

This study describes the landscape of biobanks as federated medical data lakes such as the collections of samples and their annotations in the European federation of biobanks (Biobanking and Biomolecular Resources Research Infrastructure – European Research Infrastructure Consortium, BBMRI-ERIC) and develops a conceptual model capturing schema information with quality annotation. This paper discusses the quality dimensions for data sets for medical research in-depth and proposes representations of both the metadata and data quality documentation with the aim to support researchers to effectively and efficiently identify suitable data sets for medical studies.

This novel conceptual model for metadata for medical data lakes has a unique focus on the high privacy requirements of the data sets contained in medical data lakes and also stands out in the detailed representation of data quality and metadata quality of medical data sets.

This paper aims to develop thermal analysis method of thermal joints characterization. The impact on convection on thermal resistance analysis with use thermography for silver-based thermal joints were investigated for non-metallized and metalized semiconductor surfaces. Heat transfer efficiency depends on thermal conductivity; radiation was used to perform thermographic analysis; the convection is energy loss, so its removing might improve measurements accuracy.

Investigation of thermal joints analysis method was focused on determination of convection impact on thermal resistance thermographic analysis method. Measuring samples placed in vacuum chamber with lowered pressure requires transparent window for infrared radiation that is used for thermographic analysis. Impact of infrared window and convection on temperature measurements and thermal resistance were referred.

The results showed that the silicon window allowed to perform thermal analysis through, and the convection was heat transfer mode which create 15% energy loss.

It is possible to measure thermal resistance for silver-based thermal joints with convection eliminated to improve measurements accuracy.

The effects of board composition on performance have long been discussed in management research using fractionalization measures. In this study, we propose an alternative measurement approach based on board polarization.

Using an exploratory analysis and applying the polarization measure to German Deutscher Aktienindex (DAX)-, Midcap-DAX (MDAX)- and Small Cap-Index (SDAX)-listed companies, this paper applies the polarization index to examine the relationship between board diversity and performance.

The results show that the polarization concept is well suited to measure principal-agent problems between the members of the management and supervisory boards. We reveal that board polarization is negatively associated with firm performance, as measured by return on investment (ROI).

This exploratory study shows that the measurement of board polarization can be linked to performance differences between companies, which offers promising starting points for further research.

The study aims to investigate the utilisation of open research data repositories (RDRs) for storing and sharing research data in higher learning institutions (HLIs) in Tanzania.

A survey research design was employed to collect data from postgraduate students at the Nelson Mandela African Institution of Science and Technology (NM-AIST) in Arusha, Tanzania. The data were collected and analysed quantitatively and qualitatively. A census sampling technique was employed to select the sample size for this study. The quantitative data were analysed using the Statistical Package for the Social Sciences (SPSS), whilst the qualitative data were analysed thematically.

Less than half of the respondents were aware of and were using open RDRs, including Zenodo, DataVerse, Dryad, OMERO, GitHub and Mendeley data repositories. More than half of the respondents were not willing to share research data and cited a lack of ownership after storing their research data in most of the open RDRs and data security. HILs need to conduct training on using trusted repositories and motivate postgraduate students to utilise open repositories (ORs). The challenges for underutilisation of open RDRs were a lack of policies governing the storage and sharing of research data and grant constraints.

Research data storage and sharing are of great interest to researchers in HILs to inform them to implement open RDRs to support these researchers. Open RDRs increase visibility within HILs and reduce research data loss, and research works will be cited and used publicly. This paper identifies the potential for additional studies focussed on this area.

Companies are discovering the power of crowdsourcing as a source of new ideas for products and services. It is assumed that the personal engagement and the continuous involvement with a company’s products or services over a period of several weeks positively affect participants’ loyalty intentions toward the host companies. The research leads the authors to challenge this assumption. In addition to mere participation in crowdsourcing initiatives, the authors argue that perceptions of fairness will explain changes in customer relationship-related consequences such as loyalty, perceived innovativeness and product interest. The paper aims to discuss these issues.

The authors analyzed a real-life crowdsourcing contest launched by a leading lighting manufacturer and investigated the impact of two fairness dimensions (distributive and procedural) on participants’ future behavioral and attitudinal intentions (n=121). The analysis was performed with SEM.

The results suggest that fairness perceptions are significantly related to evoked product interest, perceived innovativeness and loyalty intentions. The analysis reveals that the influence of the fairness dimensions is asymmetric: while distributive fairness can be considered as a basic factor that must be fulfilled in order to avoid negative behavioral consequences, procedural fairness instead is an excitement factor that causes truly positive behavioral consequences.

The results are particularly relevant for companies launching a crowdsourcing competition under their own brand name, and for broadcasting platforms. For companies with no relations to end-users, these findings may not be as relevant.

Organizers of crowdsourcing contests should be aware that such initiatives can be a double-edged sword. Fair Play is a must to gain the positive effects from crowdsourcing initiatives for both new product development and the customer relationship. For companies lacking the capabilities to manage crowdsourcing initiatives professionally it is advisable to rely on intermediary broadcasting platforms.

The research is the first to investigate systematically the consequences of fairness perceptions in a real-life crowdsourcing idea contest. The authors demonstrate the asymmetric nature of fairness perceptions on three different outcome variables that are important for the customer relationship.

This study aims to elucidate the quantitative and qualitative differences in employment development between German districts. Building on ideas from competitive development and resource-based theory, the paper particularly seeks to explain enduring East-West differences between rural regions by two different forms of competitive advantage: cost leadership and quality differentiation.

This study follows a two-step empirical approach: First, an extended shift-share regression is conducted to analyze employment development in Western and Eastern German districts between 2007 and 2016. Second, the competitive share effect and other individual terms of the shift-share model are further examined in additional regressions using regional economic characteristics as exogenous variables.

The findings suggest that the above-average employment growth of the rural districts in the West is owed to the successful exploitation of experience in manufacturing that has been gathered by firms in the past 100 years or so. While their strategy is largely based on advanced and specialized resources and an innovation-driven differentiation strategy, the relatively weak employment development of Eastern rural districts might be explained by a lack of comparable long-term experiences and the related need to focus on the exploitation of basic and general resources and, accordingly, on the efficiency-based strategy of cost leadership.

This study offers an in-depth empirical analysis of how the competitive share effect, i.e. region-specific resources beyond industry structure, contributes to regional employment development. The analysis reveals that quantitative differences in rural employment development are closely related to qualitatively different levels of input factors and different regimes of competitiveness.