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The purpose of this paper is to present a methodology for calculating eddy current losses in the core of a single-phase power voltage transformer, which, unlike a standard power transformer, has an open-type core (I-type core). In those apparatus, reduction of core losses is achieved by using a multipart open-type core that is created by merging a larger number of leaner cores.

3D FEM approach for calculation of eddy current losses in open-type cores based on a weak AλA formulation is presented. Method in which redundant degrees of freedom are eliminated is shown. This enables faster convergence of the simulation. The results are benchmarked using simulations with standard AVA formulation.

Results using weak AλA formulation with elimination of redundant degrees of freedom are in agreement with both simulation using only weak AλA formulation and with simulation based on AVA formulation.

The presented methodology is valid in linear cases, whereas the nonlinear case will be part of future work.

Presented procedure can be used for the optimization when designing the open-type core of apparatus like power voltage transformers.

The presented method is specifically adapted for calculating eddy currents in the open-type core. The method is based on a weak formulation for the magnetic vector potential A and the current vector potential λ, incorporating numerical homogenization and a straightforward elimination of redundant degrees of freedom, resulting in faster convergence of the simulation.

The purpose of the paper is to clarify the influence of introducing magnetic concentrators on the performance of Hall effect based current sensors and to obtain dependencies of the sensor characteristics on the conductor position.

The finite element method and Comsol software are used for analysis of the three-dimensional magnetic field of the constructions of Hall effect based current sensor with different types of magnetic concentrators – closed-core (of rectangular and toroidal type) and open-core of toroidal type – with additional larger air gap. The Hall plate is also included in the model with its real dimensions and the magnetic flux density is obtained by integrating over its volume.

It has been found that there is dependence of the output signal (proportional to the magnetic flux density) of Hall effect based current sensor with both closed- and open-core magnetic concentrators on the position of the current carrying conductor. Distribution of the magnetic flux density and dependencies of its value in the Hall plate on the conductor position and on the additional air gap have been obtained. Optimization is carried out with respect to the additional air gap and cross-section dimensions of the concentrator.

Estimation of the influence of the introducing magnetic concentrators is made with respect to relationships between the output signal and conductor position for different constructions of the magnetic core of the concentrators.

The purpose of this paper is to explore how an organization can combine different types of open innovations and what are the key factors that may influence the combination of different open innovations.

The basic methodology of this paper is the longitudinal inductive analysis within the conceptual framework of the open innovation proposed by Dahlander and Gann (2010). In this case study of Xiaomi Tech Inc., the open innovation combination is investigated through examining 25 new products created between August 2010 and December 2016 in terms of four general types: acquiring, sourcing, selling and revealing open innovation.

In practice, the combination of different types of open innovations can be realized. A firm may combine different open innovations at three levels: a single product level, a related product cluster level and a company level. In addition, different open innovations can be combined in diverse modes. The purpose of combining different types of open innovations is to overcome the disadvantages of each type and to exploit the advantages of all different types. Many factors may affect a firm’s option of how to combine open innovations. At different development stages, a firm may make and implement corresponding strategic direction based on its innovation capacity and internal resource. For a given strategy, the firm needs to create profits and manage intellectual property in the implementation of open innovations. These factors are interacted each other, rather than isolated.

The findings of this paper are helpful for better understanding how and why an organization can combine different types of open innovations. From a managerial point of view, an organization may combine different types of open innovations to leverage advantages and avoid disadvantages of each certain type of open innovation. An appropriate combination of different open innovations can effectively improve new product development.

The purpose of this paper is to verify results related to losses in the core of a brushless DC prototype motor, obtained using its computer FE models, by experimental tests on manufactured machines. The paper focuses on the comparison of losses in the core of a machine with a classical stator core made of an iron–silicon material (Fe–Si) and a new one made of a modern METGLAS material.

Computer models of the prototype motors were created using FEM. The designed machines were manufactured, and experimental tests were performed. To achieve high frequencies in rotating magnetic fields, motors with a stator to rotor pole ratio of 9/12 were built. Twin rotor approach was applied, as two identical rotors were built along the two geometrically identical stators made of different core materials.

Experimental studies have shown the superiority of the METGLAS material over the classical Fe–Si material. Material parameters were measured directly on the prepared cores as library data used in the simulation may be incorrect due to technological processes during core production, which was also verified. Problems related to twin rotor approach have been identified. Solution to the problem has been suggested. Necessity of 3D FEM modelling was identified.

The main source of originality is that METGLAS material used in the prototype machines was developed and manufactured by the authors themselves. Original approach to core parameter evaluation based on simplified methodology has been suggested. Another original part is a simplified methodology applied to loss measurement during no-load test.

The purpose of this paper is to consider a constructional solution of the combined instrument transformer: constructed so that the voltage part is a column transformer, which means that the magnetic circuit of it is open and situated into a composite insulator. The aim of this research was to achieve optimal configuration of open magnetic circuit of the column voltage transformer.

The authors made analyses of electromagnetic field distribution and computed the voltage error and phase displacement for many different cases of magnetic circuits of the column voltage transformers. The analyses of the electromagnetic field distribution and computations were carried out using the 3D field‐circuit method based on the finite‐element numerical method. The results were compared with tests of a real‐life model.

The result of research is the selection of the best constructional version of the column voltage transformer; the research also gives some guidelines for design and manufacture of this construction of combined transformers.

The paper is meant for constructors of instrument transformers and presents results of research into new constructional solutions of combined transformer.

The purpose of the paper is to introduce standardization as a neutral arena for open innovation. The aim is to show that different policies towards open membership in standardization initiatives lead to different open innovation processes.

Two cases are used to illustrate the differences in open innovation processes. The cases are the Android mobile operating system and the service platform developed by the Open Mobile Alliance. The core process types introduced by Gassmann and Enkel are used to show the different open innovation approaches.

Both cases use open innovation to create standards. Open membership leads to a coupled process, while a more restricted membership gives separate inside‐out and outside‐in processes. The case lead by established firms in the industry has a process where radical innovations are introduced early in the process, while the case lead by newcomers has a process where radical innovations are introduced late in the process. The two cases have different approaches towards commercialization of the products. Android relies on third‐party developers, while the Open Mobile Alliance relies on their own members.

The cases are from the telecommunication sector and based on standardization of large technical platforms. The findings might not be the same for other sectors.

The paper establishes open innovation as a neutral arena for open innovation outside the domain of any single firm. It shows how the openness towards membership influences the choice of open innovation processes.

The purpose of this paper is to contribute to the literature about the commercial involvement in open source software, levels of this involvement and consequences of attempting to mix various logics of action.

This paper uses the case study approach based on mixed methods: literature reviews and news searches, electronic surveys, qualitative interviews and observations. It combines discussions from several research projects as well as previous publications to present the scope of commercial choices within open source software and their consequences.

The findings show that higher levels of involvement in open source software communities poses important questions about the balance between economic, technological, and social logics as well as the benefits of being autonomous, having access to collaborative networks and minimizing risks related to free-riding. There are six levels of commercial involvement in open source communities, and each of them is characterized by a different dilemma.

The paper sheds light on the various level of involvement of business in open source movement and emphasize that the popularized “open innovation” concept is only the first step in real involvement and paradigm shift.

The link between mergers and acquisitions (M&A) and innovation has been analysed in both corporate finance studies and the innovation literature. Despite this attention and the practical evidence that highlights different connections between these two terms, there is a need to investigate the latest trends with regard to these important topics, and to put a particular focus on the emerging paradigm of open innovation. Thus, this paper aims to provide a systematic literature review (SLR) about the relationship between M&As and the concept of innovation in the current scenario.

Through an SLR from 2012 to June 2017, 55 papers have been identified and analysed to give a better understanding of the motivations and the methodologies adopted in past studies.

This paper identifies various conceptual and research methodological characteristics of studies that have connected, directly or indirectly, M&As and innovation in recent years. In addition, the results highlight a scarcity of studies that explicitly or implicitly refer to the open innovation paradigm, marking only a partial understanding of this emerging phenomenon.

This paper improves the knowledge on the link between extraordinary corporate transactions and innovation, and it highlights that a clear consensus, particularly regarding the open innovation paradigm, is lacking. Thus the authors propose that future studies should carefully evaluate M&As by following the open innovation approach.

The purpose of this paper is to explore the ideological foundation of open innovation strategies and the open business model, which are appearing as new industrial paradigms based on information technology (IT).

First, this paper examined the ideological foundation of Deleuze, Whitehead, and Popper. Next, Taoism was scrutinized to discover concrete bases for open innovation.

Here, it was found that Taoism completely coincides with the logical basis of open innovation. The theory “the supreme good is like water” of Taoism means to vacate oneself and fill the space with others to create paradoxes, thereby filling oneself with a more creative method.

Taoism provides a way to present paradoxes through the idea of vacating and opening to reach a creative stage of leaving nature as it is.

Core groups stand as the tangible, but fluid repositories of knowledge, influence and power in organizations. Thus, the core group in any organization is the focal point of organizational learning throughout the organization, because people act to fulfill the perceived needs and priorities of some key group of people. An organization goes wherever its people perceive that the core group needs and wants to go. An organization becomes whatever its people perceive that the core group needs and wants it to become. Core Group Theory holds implications for how the complex of power, knowledge and influence interacts with organizational opportunities for genuine learning and creativity.