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Article
Publication date: 1 January 1988

Nathan IDA

Problem 2 of the International Workshop for Eddy Current Code Comparison is a hollow cylinder with its axis perpendicular to a uniform sinuosoidal field. A total of 10…

Abstract

Problem 2 of the International Workshop for Eddy Current Code Comparison is a hollow cylinder with its axis perpendicular to a uniform sinuosoidal field. A total of 10 solutions, employing 9 different computer codes, are described and compared with analytic results. Most codes were 2‐D finite element and were found to give satisfactory solutions.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 7 no. 1/2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 30 September 2014

Pedro Miguel de Almeida Areias, Timon Rabczuk and Joaquim Infante Barbosa

– The purpose of this paper is to discuss the linear solution of equality constrained problems by using the Frontal solution method without explicit assembling.

Abstract

Purpose

The purpose of this paper is to discuss the linear solution of equality constrained problems by using the Frontal solution method without explicit assembling.

Design/methodology/approach

Re-written frontal solution method with a priori pivot and front sequence. OpenMP parallelization, nearly linear (in elimination and substitution) up to 40 threads. Constraints enforced at the local assembling stage.

Findings

When compared with both standard sparse solvers and classical frontal implementations, memory requirements and code size are significantly reduced.

Research limitations/implications

Large, non-linear problems with constraints typically make use of the Newton method with Lagrange multipliers. In the context of the solution of problems with large number of constraints, the matrix transformation methods (MTM) are often more cost-effective. The paper presents a complete solution, with topological ordering, for this problem.

Practical implications

A complete software package in Fortran 2003 is described. Examples of clique-based problems are shown with large systems solved in core.

Social implications

More realistic non-linear problems can be solved with this Frontal code at the core of the Newton method.

Originality/value

Use of topological ordering of constraints. A-priori pivot and front sequences. No need for symbolic assembling. Constraints treated at the core of the Frontal solver. Use of OpenMP in the main Frontal loop, now quantified. Availability of Software.

Details

Engineering Computations, vol. 31 no. 7
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 March 1986

Peter Bettess and Jacqueline A. Bettess

A profile solver which factorizes the profile matrix K into the form LDLT, is described. D is a diagonal matrix and L is a lower triangular matrix. LT is stored by…

Abstract

A profile solver which factorizes the profile matrix K into the form LDLT, is described. D is a diagonal matrix and L is a lower triangular matrix. LT is stored by columns, using a steering vector, to locate the elements. In addition a fixity vector is used. This indicates which degrees of freedom are free and which are fixed. A main program uses a random number generator to set up test data. Full listings are given, together with information on how to get a copy of the program.

Details

Engineering Computations, vol. 3 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 February 2000

A.N. Pavlov, S.S. Sazhin, R.P. Fedorenko and M.R. Heikal

Detailed results of numerical calculations of transient, 2D incompressible flow around and in the wake of a square prism at Re = 100, 200 and 500 are presented. An…

Abstract

Detailed results of numerical calculations of transient, 2D incompressible flow around and in the wake of a square prism at Re = 100, 200 and 500 are presented. An implicit finite‐difference operator‐splitting method, a version of the known SIMPLEC‐like method on a staggered grid, is described. Appropriate theoretical results are presented. The method has second‐order accuracy in space, conserving mass, momentum and kinetic energy. A new modification of the multigrid method is employed to solve the elliptic pressure problem. Calculations are performed on a sequence of spatial grids with up to 401 × 321 grid points, at sequentially halved time steps to ensure grid‐independent results. Three types of flow are shown to exist at Re = 500: a steady‐state unstable flow and two which are transient, fully periodic and asymmetric about the centre line but mirror symmetric to each other. Discrete frequency spectra of drag and lift coefficients are presented.

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International Journal of Numerical Methods for Heat & Fluid Flow, vol. 10 no. 1
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 1 June 2004

Corey Keith

This paper describes the MARCXML architecture implemented at the Library of Congress. It gives an overview of the component pieces of the architecture, including the…

Abstract

This paper describes the MARCXML architecture implemented at the Library of Congress. It gives an overview of the component pieces of the architecture, including the MARCXML schema and the MARCXML toolkit, while giving a brief tutorial on their use. Several different applications of the architecture and tools are discussed to illustrate the features of the toolkit being developed thus far. Nearly any metadata format can take advantage of the features of the toolkit, and the process of the toolkit enabling a new format is discussed. Finally, this paper intends to foster new ideas with regards to the transformation of descriptive metadata, especially using XML tools. In this paper the following conventions will be used: MARC21 will refer to MARC 21 records in the ISO 2709 record structure used today; MARCXML will refer to MARC 21 records in an XML structure.

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Library Hi Tech, vol. 22 no. 2
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 1 March 1992

G. Franke

This paper provides some justification for the observation that managers hedge transaction and translation risk through financial contracts and not economic risk as…

Abstract

This paper provides some justification for the observation that managers hedge transaction and translation risk through financial contracts and not economic risk as recommended by economists. One reason for the observed behavior is uncertainty in the perception of economic risk. If the manager is more heavily penalized for mishedging than rewarded for proper hedging, then uncertainty of perception may induce him not to hedge economic risk. Another reason is that accounting rules may lead to high accounting losses if economic risk is properly hedged by financial contracts.

Details

Managerial Finance, vol. 18 no. 3
Type: Research Article
ISSN: 0307-4358

Content available
Article
Publication date: 11 March 2021

Luiz Guilherme Rodrigues Antunes, Cleber Carvalho de Castro and Andrea Ap da Costa Mineiro

The purpose of this paper is to analyze the performance of incubators in the stages of formation and development of incubated business networks, especially in bottom-up…

Abstract

Purpose

The purpose of this paper is to analyze the performance of incubators in the stages of formation and development of incubated business networks, especially in bottom-up and top-down network models.

Design/methodology/approach

The research is defined as qualitative and descriptive, with the application of multiple case studies, in which two networks of incubated businesses were investigated, one being top-down and the other bottom-up, which emerged within the incubation process of two business incubators (CIETEC and INCIT). To make the study operational, 11 semi-structured interviews were carried out and the thematic analysis of content was developed.

Findings

The results pointed out that in the top-down network the incubator performs a new assignment, the network orchestration, which corresponds to the actions of formation, coordination and governance of the group. In the bottom-up network, it was found that the role of the incubator was to expand the value offers usually practiced.

Research limitations/implications

As a limitation of the research, the very limitation of case studies is pointed out that is they do not allow for generalizations.

Practical implications

The research contributes to reflections on the effectiveness of the incubator and sheds light on the complementarity of networks in incubation processes, providing gains for incubators, incubated businesses and society.

Originality/value

The originality of this document is the new role of the incubator, which is orchestration, and its categorization. The results allow us to understand the effects of providing networks and relationships for incubated businesses. In addition, this study broadens the focus of traditional analyses of the incubator–incubated duo to consider the incubator–network–incubated trio.

Details

Innovation & Management Review, vol. 18 no. 1
Type: Research Article
ISSN: 2515-8961

Keywords

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Book part
Publication date: 30 October 2009

Ricardo Mora and Javier Ruiz-Castillo

In the context of educational segregation by ethnic group, it has been argued that rigorous pairwise segregation comparisons over time or across space should be invariant…

Abstract

In the context of educational segregation by ethnic group, it has been argued that rigorous pairwise segregation comparisons over time or across space should be invariant in two situations: when the ethnic composition of the population changes while the distribution of each ethnic group over the schools remains constant (invariance 1), or when the size distribution of schools changes while the ethnic composition of each school remains constant (invariance 2). This paper makes two contributions to the segregation literature. First, it argues by means of the Mutual Information or M index, which is neither invariant 1 nor 2, that both properties have strong implications, and it provides reasons to defend that the overall segregation index need not satisfy either one. Second, nevertheless, it is shown that in pairwise comparisons this index admits two decompositions into three terms. In the first decomposition, a term is invariant 1 and also satisfies a weak version of invariance 2. In the second decomposition, a term is invariant 2 and also satisfies a weak version of invariance 1. It is shown that these decompositions can be used to reach the analogous ones obtained in Deutsch et al. (2006).

Details

Occupational and Residential Segregation
Type: Book
ISBN: 978-1-84855-786-4

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Article
Publication date: 1 February 1974

A.J.‐P. ALTMANN

Line theory and the description of phenomena in subthreshold stimulated nerve fibres have many common features. This paper offers accurate formulations of these relations…

Abstract

Line theory and the description of phenomena in subthreshold stimulated nerve fibres have many common features. This paper offers accurate formulations of these relations. It starts with the partial differential equation u″ = r1 · Cm · u + r1gm · u for subthreshold changes of the deviation of the membrane potential from the resting value. For sinusoidal stimulation the characteristic quantities describing the subthreshold behaviour of a nerve fibre are derived from this equation. For step stimulation a (the attenuation constant) becomes independent of frequency and is a measure of the spatial decay of the membrane voltage changes, while transients are characterized by the time constant of the nerve fibre. The investigation of biological processes in neuron systems with the help of electro‐technical concepts may be included in the realm of cybernetic methods.

Details

Kybernetes, vol. 3 no. 2
Type: Research Article
ISSN: 0368-492X

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Book part
Publication date: 16 October 2020

Ângela Gonçalves, Dina Pereira, João Leitão and Maria del Mar Fuentes

This chapter uses an intellectual capital (IC) qualitative approach for assessing the bio health technologies entrepreneurial ecosystem of a university located in Southern…

Abstract

This chapter uses an intellectual capital (IC) qualitative approach for assessing the bio health technologies entrepreneurial ecosystem of a university located in Southern Europe, aiming to identify the role played by IC in fostering the sustainable success of the entrepreneurial ecosystem. There has been limited research dedicated to deepening the knowledge of the entrepreneurial ecosystems’ dimensions, using an IC lens, in the context of university cities with different dimensions. Small cities may not have some dimensions, so developed, comparing with the ones of the ecosystems of large urban centers. This chapter uses a qualitative approach funded in a case study exploring internal and external stakeholders of a Portuguese entrepreneurial ecosystem, UBImedical, targeted at the bio health sector. The study is part of an exploratory study funded in the scope of a European Project, aiming to explore in a pioneering way the application of the dominant triad of capitals forming IC and, thus, identifying and understanding the dimensions of different entrepreneurial ecosystems. The case study reveals that the IC’s dimensions more critical for the success of the bio health entrepreneurial ecosystems are the structural capital and the relational capital, although human capital is perceived as a basic prerequisite for fostering the entrepreneurial ecosystem’s performance. The results are funded in primary and qualitative data collected from the interviews developed to previously identified external and internal stakeholders of this type of entrepreneurial ecosystem under study.

Details

A Guide to Planning and Managing Open Innovative Ecosystems
Type: Book
ISBN: 978-1-78973-409-6

Keywords

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