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1 – 10 of 13Martin Hafner, Marc Schöning and Kay Hameyer
The purpose of this paper is to consider thermal analysis as part of an automated sizing and design process. The temperature estimation at characteristic points of the machine…
Abstract
Purpose
The purpose of this paper is to consider thermal analysis as part of an automated sizing and design process. The temperature estimation at characteristic points of the machine, and in particular in permanent magnets, is essential to accurately simulate the electromagnetic behavior and avoid irreversible demagnetization.
Design/methodology/approach
In this paper, an electromagnetic dimensioning model, parameterized by finite element analysis, is coupled to a thermal lumped‐parameter model to constitute a fast and efficient design tool for electrical machines.
Findings
A parameterized and hybrid FE‐analytical electromagnetic model, which combines analytical and numerical advantages, to archive a fast and accurate electromagnetic simulation results is combined with a thermal lumped‐parameter model for water‐cooled and passive air‐cooled surface mounted permanent magnet synchronous machines (PMSM).
Practical implications
Sizing, electromagnetic and thermal modeling aspects are integrated into an automated design process. The whole design process is demonstrated on two standard industrial servo motors for passive and active water cooling and afterwards compared with available measurements.
Originality/value
The proposed method allows considering thermal aspects during the iterative automated electromagnetic design process of PMSM.
Details
Keywords
Timothy W. Cole, Myung-Ja K. Han, Maria Janina Sarol, Monika Biel and David Maus
Early Modern emblem books are primary sources for scholars studying the European Renaissance. Linked Open Data (LOD) is an approach for organizing and modeling information in a…
Abstract
Purpose
Early Modern emblem books are primary sources for scholars studying the European Renaissance. Linked Open Data (LOD) is an approach for organizing and modeling information in a data-centric manner compatible with the emerging Semantic Web. The purpose of this paper is to examine ways in which LOD methods can be applied to facilitate emblem resource discovery, better reveal the structure and connectedness of digitized emblem resources, and enhance scholar interactions with digitized emblem resources.
Design/methodology/approach
This research encompasses an analysis of the existing XML-based Spine (emblem-specific) metadata schema; the design of a new, domain-specific, Resource Description Framework compatible ontology; the mapping and transformation of metadata from Spine to both the new ontology and (separately) to the pre-existing Schema.org ontology; and the (experimental) modification of the Emblematica Online portal as a proof of concept to illustrate enhancements supported by LOD.
Findings
LOD is viable as an approach for facilitating discovery and enhancing the value to scholars of digitized emblem books; however, metadata must first be enriched with additional uniform resource identifiers and the workflow upgrades required to normalize and transform existing emblem metadata are substantial and still to be fully worked out.
Practical implications
The research described demonstrates the feasibility of transforming existing, special collections metadata to LOD. Although considerable work and further study will be required, preliminary findings suggest potential benefits of LOD for both users and libraries.
Originality/value
This research is unique in the context of emblem studies and adds to the emerging body of work examining the application of LOD best practices to library special collections.
Details
Keywords
To reduce the computational costs for electromagnetic simulations of permanent magnet synchronous machines maintaining a high accuracy.
Abstract
Purpose
To reduce the computational costs for electromagnetic simulations of permanent magnet synchronous machines maintaining a high accuracy.
Design/methodology/approach
An analytical model is introduced regarding multiple designs of permanent magnet synchronous machines. This electromagnetic model is coupled to a numerical simulation. Thereby, the advantages of both computational methods are combined by parameterizing the analytical model to the numerical solution. This results in a high‐efficient analytical model with the accuracy of the numerical simulation. The results of the analytical model are compared to measurements of a permanent magnet synchronous machine. Various machine modifications are simulated to evaluate possible limitations of the analytical model.
Findings
It can be stated, that a once parameterized analytical model achieves a high accuracy. Furthermore, geometric variations can be applied without the need of a new parameterization through a numerical simulation. Only changing the permanent magnet height or the air gap height results in a significant deviation and a new numerical simulation is recommended.
Research limitations/implications
Only measurements for machines up to 5 kW were available. In consequence, the model is only validatet in this range.
Practical implications
With the presented analytical model, an electromagnetic design of a permanent magnet synchronous machine can be performed very time efficient achieving accurate results. Furthermore, optimization studies can be performed with low‐computational costs.
Originality/value
The introduced analytical model can be parameterized by a numerical simulation. The numeric simulation process and the parameterization are performed automatically according to the data calculated by the analytical model. Measurements demonstrate the effectiveness and the limitations of the model.
Details
Keywords
Developing a collection of compact disc sound recordings is beginning to emerge as a goal for many libraries, yet the commitment of resources and energy involved in this effort is…
Abstract
Developing a collection of compact disc sound recordings is beginning to emerge as a goal for many libraries, yet the commitment of resources and energy involved in this effort is not to be taken lightly. In addition to the inevitable practical problems to be solved, there is the rare responsibility of constructing a collection from the ground up, an enterprise particularly challenging with a new medium. Satisfying both patron needs and staff requirements is seldom easy; the task of choosing CD's therefore requires careful thought, planning, and monitoring.
DURING the three years I have attended the meetings of this branch association, papers of so interesting a character have been read that I am well aware of the difficulty each…
Abstract
DURING the three years I have attended the meetings of this branch association, papers of so interesting a character have been read that I am well aware of the difficulty each paper reader must have in keeping up the standard. But as my subject seems a good one, you may be inclined to overlook an indifferent treatment of it.