Jinxing Shen, Jiansheng Yuan and Arnulf Kost
The computation of 3‐D eddy current problems is an important topic both in theoretical and engineering areas. Based on Green's theorem, Kost theoretically developed a BEM…
Abstract
The computation of 3‐D eddy current problems is an important topic both in theoretical and engineering areas. Based on Green's theorem, Kost theoretically developed a BEM formulation for general 3‐D nonlinear eddy current problems. The parallel implementation of this formulation in the linear case has been made on a massively parallel supercomputer, where a constant triangular element was used.
Roland Erwin Suri and Mohamed El-Saad
Changes in file format specifications challenge long-term preservation of digital documents. Digital archives thus often focus on specific file formats that are well suited for…
Abstract
Purpose
Changes in file format specifications challenge long-term preservation of digital documents. Digital archives thus often focus on specific file formats that are well suited for long-term preservation, such as the PDF/A format. Since only few customers submit PDF/A files, digital archives may consider converting submitted files to the PDF/A format. The paper aims to discuss these issues.
Design/methodology/approach
The authors evaluated three software tools for batch conversion of common file formats to PDF/A-1b: LuraTech PDF Compressor, Adobe Acrobat XI Pro and 3-HeightsTM Document Converter by PDF Tools. The test set consisted of 80 files, with 10 files each of the eight file types JPEG, MS PowerPoint, PDF, PNG, MS Word, MS Excel, MSG and “web page.”
Findings
Batch processing was sometimes hindered by stops that required manual interference. Depending on the software tool, three to four of these stops occurred during batch processing of the 80 test files. Furthermore, the conversion tools sometimes failed to produce output files even for supported file formats: three (Adobe Pro) up to seven (LuraTech and 3-HeightsTM) PDF/A-1b files were not produced. Since Adobe Pro does not convert e-mails, a total of 213 PDF/A-1b files were produced. The faithfulness of each conversion was investigated by comparing the visual appearance of the input document with that of the produced PDF/A-1b document on a computer screen. Meticulous visual inspection revealed that the conversion to PDF/A-1b impaired the information content in 24 of the converted 213 files (11 percent). These reproducibility errors included loss of links, loss of other document content (unreadable characters, missing text, document part missing), updated fields (reflecting time and folder of conversion), vector graphics issues and spelling errors.
Originality/value
These results indicate that large-scale batch conversions of heterogeneous files to PDF/A-1b cause complex issues that need to be addressed for each individual file. Even with considerable efforts, some information loss seems unavoidable if large numbers of files from heterogeneous sources are migrated to the PDF/A-1b format.
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Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community…
Abstract
Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.
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H. Igarashi, A. Kost and T. Honma
This paper describes a boundary element analysis of magnetic shieldings for electron microscopes. Since the thickness of the shielding layer is considerably small compared with…
Abstract
This paper describes a boundary element analysis of magnetic shieldings for electron microscopes. Since the thickness of the shielding layer is considerably small compared with its overall size, numerical analysis of electromagnetic fields inside the layer leads to an ill‐conditioned matrix. This problem can be overcome by analytical evaluation of the interior electromagnetic field, which yields the impedance boundary condition (IBC) valid for static and eddy current fields, which expresses the relationship between the electromagnetic fields on both surfaces of the layer. In this paper the magnetic fields around a shielding layer are analyzed by the boundary element method under the IBC on the shielding layer. Two‐dimensional and axisymmetric magnetic fields are analyzed to evaluate the shielding efficiency of shielding immersed in an ac magnetic field. It is shown that magnetic disturbances can be reduced to less than one‐hundredth inside a shielding consisting of double shielding layers.
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Ulf Papenfuß, Iris Saliterer and Nora Albrecht
This chapter investigates financial resilience of German local governments. The local governments included in this analysis challenged the applicability of the financial…
Abstract
This chapter investigates financial resilience of German local governments. The local governments included in this analysis challenged the applicability of the financial resilience concept by reporting no significant direct impact of the financial crisis during the last 10 years. This is also in line with more general observations suggesting that Germany weathered the financial crisis successfully and without the dramatic effects on its local governments that are observable in other countries. During semi-structured interviews with key administrative decision-makers, it turned out that the financial crisis impacted the local governments’ commercial tax revenues only in its aftermath, and respondents rather highlighted the refugee crisis in 2015 and sudden changes in the tax base caused by relocation, bankruptcy or economic turmoil as financial shocks. More general trends, for example, upper governmental levels devolving more service and administrative responsibility without sufficient compensation, and in particular long-term issues, that is, high debt levels magnifying effects of financial shocks, seem to challenge German local governments. Some cases included in this investigation seem reluctant to make conflict-laden, but necessary changes, and feel exposed to policies and regulations by upper governmental levels. This creates uncertainty and at times leaves them in a sense of helplessness and infeasibility of proper planning. However, the need for investing resources to build up internal capacities has already been pointed out. From a financial resilience perspective, this seems even more important in a context where relying on buffering was feasible, but might prove insufficient once other internal capacities are required to tackle local governments’ financial vulnerabilities.
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Djonny Weinzierl, Adroaldo Raizer, Arnulf Kost and Golberi de Salvador Ferreira
This paper presents the use of transmission‐line modelling ‐ time domain (TLM‐TD) method to analyse the fields in mode stirred reverberation chambers excited by wires. It will be…
Abstract
This paper presents the use of transmission‐line modelling ‐ time domain (TLM‐TD) method to analyse the fields in mode stirred reverberation chambers excited by wires. It will be shown how the fields inside the chamber are distributed for a large range of excited frequencies. The work intends to develop a numerical procedure to verify the effectiveness and usefulness of the TLM method to electromagnetic compatibility problems. The numerical model presented here is based on the classical symmetrical condensed 3D node. The simulations will be compared with method of moments results obtained in available benchmark data. Some comments are made on comparisons between the two techniques.
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To explore the politics of gender, health, medicine, and citizenship in high-income countries, medical sociologists have focused primarily on the practice of legal abortion. In…
Abstract
To explore the politics of gender, health, medicine, and citizenship in high-income countries, medical sociologists have focused primarily on the practice of legal abortion. In middle- and low-income countries with restrictive abortion laws, however, medical sociologists must examine what happens when women have already experienced spontaneous or induced abortion. Post-abortion care (PAC), a global reproductive health intervention that treats complications of abortion and has been implemented in nearly 50 countries worldwide, offers important theoretical insights into transnational politics of abortion and reproduction in countries with restrictive abortion laws. In this chapter, I draw on my ethnography of Senegal’s PAC program to examine the professional, clinical, and technological politics and practices of obstetric care for abortions that have already occurred. I use the sociological concepts of professional boundary work and boundary objects to demonstrate how Senegalese health professionals have established the political and clinical legitimacy of PAC. I demonstrate the professional precariousness of practicing PAC for physicians, midwives, and nurses. I show how the dual capacity of PAC technologies to terminate pregnancy and treat abortion complications has limited their circulation within the health system, thereby reducing quality of care. Given the contradictory and complex global landscape of twenty-first-century abortion governance, in which pharmaceutical forms of abortion such as Misoprostol are increasingly available in developing countries, and as abortion restrictions are increasingly enforced across the developed world, PAC offers important theoretical opportunities to advance medical sociology research on abortion politics and practices in the global North and South.
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The development of electrical machines is nowadays closely related to the knowledge of the electromagnetic fields throughout the different parts of a machine. Although a machine…
Abstract
The development of electrical machines is nowadays closely related to the knowledge of the electromagnetic fields throughout the different parts of a machine. Although a machine is often of complicated geometrical structure and of different, mostly nonlinear materials, modern numerical methods and the related software allow calculation of the fields in 2D models and several 3D cases precisely enough in order to derivate from them quantities like energy density distribution, the torque behaviour and characteristics like load and no load. The paper will at first compare numerical methods suited for electromagnetic field calculation in electrical machines. The following topic deals with adaptive mesh generation playing an important role to save computer memory and cpu time. Then examples like a Switched Reluctance Machine, an Asynchronous Machine and a Stepping Motor are shown concerning the results of field calculation. It is shown that anisotropy may have to be taken into account, and finally it is shown that field calculation enables the shape optimization of a machine.
J. Bart Stykes and Karen Benjamin Guzzo
A robust body of scholarship has attached unintended childbearing, cohabitation, and stepfamily living arrangements to a greater risk of union instability in the United States…
Abstract
A robust body of scholarship has attached unintended childbearing, cohabitation, and stepfamily living arrangements to a greater risk of union instability in the United States. These aspects of family life, which often co-occur, are overrepresented among disadvantaged populations, who also have an independently higher risk of union instability. Existing scholarship has modeled these family experiences as correlated events to better understand family and union instability, yet the authors assert a direct effort to test whether or how unintended childbearing differs across marital and stepfamily statuses makes important contributions to established research on relationship stability. Drawing on the 2006–2017 National Survey of Family Growth (NSFG), the authors test potential moderating effects to better understand the linkages between unintended childbearing and union dissolution among 7,864 recent, higher-order births to partnered mothers via discrete-time, event history logistic regression models. Findings confirm that unintended childbearing, cohabitation, and stepfamily status are all linked with a greater risk of dissolution. However, unintended childbearing is differentially linked to instability by marital status, with unintended childbearing being associated with a higher risk of dissolution for married couples relative to cohabiting couples. Unintended fertility does not seem to increase the risk of instability across stepfamily status. Findings provide more evidence in support of selection, rather than causation, in explaining the association between unintended childbearing and union instability among higher-order births. Results suggest that among higher-order births, unintended childbearing may reflect underlying relationship issues.
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Dieter Lederer, Hajime Igarashi, Arnulf Kost and Toshihisa Honma
The calculation of magnetic shielding with ferromagnetic material by an effective reluctivity method and a time step method based on the finite element calculation is…
Abstract
The calculation of magnetic shielding with ferromagnetic material by an effective reluctivity method and a time step method based on the finite element calculation is investigated. The calculation results of both methods are compared with measurement results and with each other in order to check their reliability and accuracy. It turns out that both methods give similar results for the field inside the shielding material, whereas in the surrounding air the effective reluctivity method gives more accurate results than the present time step method.