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Article
Publication date: 7 August 2017

Zbigniew Magonski and Barbara Dziurdzia

The aim of this paper is to find the electrical representation of a solid oxide fuel cell (SOFC) that enables the application of typical exploitation characteristics of…

Abstract

Purpose

The aim of this paper is to find the electrical representation of a solid oxide fuel cell (SOFC) that enables the application of typical exploitation characteristics of fuel cells for estimation of fuel cell parameters (for example, exchange current) and easy analysis of phenomena occurred during the fuel cell operation.

Design/methodology/approach

Three-layer structure of an SOFC, where a thin semi-conducting layer of electrolyte separates the anode from the cathode, shows a strong similarity to typical semiconductor devices built on the basis of P-N junctions, like diodes or transistors. Current–voltage (I-V) characteristics of a fuel cell can be described by the same mathematical functions as I-V plots of semiconductor devices. On the basis of this similarity and analysis of impedance spectra of a real fuel cell, two electrical representations of the SOFC have been created.

Findings

The simplified electrical representation of SOFC consists of a voltage source connected in series with a diode, which symbolizes a voltage drop on a cell cathode, and two resistors. This model is based on the similarity of Butler-Volmer to Shockley equation. The advanced representation comprises a voltage source connected in series with a bipolar transistor in close to saturation mode and two resistors. The base-emitter junction of the transistor represents voltage drop on the cell cathode, and the base-collector junction represents voltage drop on the cell anode. This model is based on the similarity of Butler-Volmer equation to Ebers-Moll equation.

Originality/value

The proposed approach based on the Shockley and Ebers-Moll formulas enables the more accurate estimation of the ion exchange current and other fuel cell parameters than the approach based on the Butler-Volmer and Tafel formulas. The usability of semiconductor models for analysis of SOFC operation was proved. The models were successively applied in a new design of a planar ceramic fuel cell, which features by reduced thermal capacity, short start-up time and limited number of metal components and which has become the basis for the SOFC stack design.

Details

Microelectronics International, vol. 34 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 March 1989

K. SOUISSI, A. PARASKEVOPOULOS, P. DEVOLDÈRE and E. CAQUOT

A 2D numerical simulation using a finite element technique is presented for computing spreading resistance of a semiconductor buried ridge stripe laser. The simplified…

Abstract

A 2D numerical simulation using a finite element technique is presented for computing spreading resistance of a semiconductor buried ridge stripe laser. The simplified physical model is analyzed from the functional analysis point of view and a proof of existence and uniqueness of the nonlinear partial differential equations obtained from this simplified model is given. The discrete associated nonlinear problem is solved on triangular finite elements using conjugate gradient algorithms. Some results are presented for a specific semiconductor laser

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 8 no. 3
Type: Research Article
ISSN: 0332-1649

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Book part
Publication date: 18 September 2018

Celeste Campos-Castillo

Existing descriptions of trust in health care largely assume a straightforward association between a patient’s relationship with a regular provider and his or her trust in…

Abstract

Purpose

Existing descriptions of trust in health care largely assume a straightforward association between a patient’s relationship with a regular provider and his or her trust in health care. I extend status characteristics theory (SCT) and social identity theory (SIT) to suggest greater variability in this association by investigating the role of social differences between patients and their regular providers. Whereas the SIT extension predicts lower trust in dissimilar than similar dyads, the predictions from the SCT extension depend on status in dissimilar dyads. Further, research examining how social differences in patient–provider dyads shape trust largely emphasizes racial differences, but the theories implicate gender differences too.

Methodology/approach

I analyze a longitudinal dataset of patient–provider dyads offering a conservative test of the extensions.

Findings

Results generally support predictions from the SCT extension. Specifically, patients’ status based on differences in either race or gender: (1) is inversely related to their trust in health care and (2) influences the resiliency of their trust, whereby the degree health care met prior expectations matters less (more) for the trust of low (high) status patients than equal status patients.

Research limitations/implications

When patients and providers differ on both race and gender, findings sometimes depart from predictions. This indicates differences in two social categories is a unique situation where the contributions of each category are distinct from that of the other.

Originality/value

This research extends SCT to explain greater variability in the connection between patient–provider dyads and trust in health care, while also showing how gender compares to race.

Details

Gender, Women’s Health Care Concerns and Other Social Factors in Health and Health Care
Type: Book
ISBN: 978-1-78756-175-5

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Article
Publication date: 1 September 1997

M. Isberg, P. Jonsson, N. Keskitalo, F. Masszi and H. Bleicher

Shows how a sensitivity analysis of different mobility models was carried out in order to reach the best fit of simulation results to measured data. Simulated data were…

Abstract

Shows how a sensitivity analysis of different mobility models was carried out in order to reach the best fit of simulation results to measured data. Simulated data were compared to both electrical (IV‐characteristics) and optical (excess charge carrier distribution) results. The simulations included both steady state and transient investigations on a temperature scale ranging from room temperature up to 150°C. Concerning lifetimes, a two‐trap Shockley‐Read‐Hall (SRH) recombination model was implemented into the simulation code to be able to model the local lifetime variations of the irradiated samples. At high carrier concentration, the overall dominating recombination process is the Auger process. From experimental data the Auger coefficients seem to be concentration dependent too, and in addition, proposes a temperature dependence to the Auger coefficient.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 16 no. 3
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 June 2002

George K. Chacko

Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade…

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Abstract

Develops an original 12‐step management of technology protocol and applies it to 51 applications which range from Du Pont’s failure in Nylon to the Single Online Trade Exchange for Auto Parts procurement by GM, Ford, Daimler‐Chrysler and Renault‐Nissan. Provides many case studies with regards to the adoption of technology and describes seven chief technology officer characteristics. Discusses common errors when companies invest in technology and considers the probabilities of success. Provides 175 questions and answers to reinforce the concepts introduced. States that this substantial journal is aimed primarily at the present and potential chief technology officer to assist their survival and success in national and international markets.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 14 no. 2/3
Type: Research Article
ISSN: 1355-5855

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Article
Publication date: 2 September 2014

Peter Brous, Bonnie G. Buchanan and Tony Orcutt

The “raise your rate” (RYR) certificate of deposit (CD) allows investors to raise the rate on their CD to the current market rate over the life of the CD. The purpose of…

Abstract

Purpose

The “raise your rate” (RYR) certificate of deposit (CD) allows investors to raise the rate on their CD to the current market rate over the life of the CD. The purpose of this paper is to present a binomial option pricing model to value this option to raise the rate. The model also demonstrates conditions under which the investor should choose to exercise their option and raise their rate prior to maturity. Understanding the value of this option is useful to both banks setting rates, and investors comparing alternative investment opportunities. The results of this model suggest that, for CDs with short maturities and low yields, the value of the option is relatively small, roughly one to four basis points, however, for CDs with longer maturities and higher yields the value of the option can be as much as 50-80 basis points.

Design/methodology/approach

This paper demonstrates how to value raise your rate CDs by applying a binomial option pricing model and provides the value of this option over a range of current CD yields and over a range of CD maturities.

Findings

When CD rates are low and maturities are short the value of the option is small (one to four basis points), however, when CD rates are high with longer maturities, the value of this option can be significant (50-80 basis points).

Research limitations/implications

The research implication is that the rate discount that the institution offers and the investor accepts should reflect the value of the option to raise the rate. The benefit to the institution and the cost to the investor reflected in the rate discount can be determined by the procedures presented in this paper regarding the valuation of the option to raise the rate.

Practical implications

The purpose of this paper is to demonstrate how to apply a binomial option pricing model to value the option that is attached to a raise your rate CD. Knowing the value of this option should be useful both to banks, in determining the discounted rate they should offer on these CDs, and to investors choosing among alternative investment opportunities. An additional benefit of applying a binomial model to value the option is that the model can be used by investors to determine the optimal point at which to exercise their option and lock in the current higher rate.

Social implications

Given the recent financial turmoil, pressure has been placed on banks to increase their liquidity and deposit base. CDs are crucial to this. Understanding the value of the RYR option is useful to both banks setting rates and investors comparing alternative investment opportunities.

Originality/value

Given the current economic climate, deciding which strategic investment options to pursue is of paramount importance. To the best of the knowledge this is the first study that applies binomial option pricing to certificates of deposit to help investors make these decisions.

Details

Managerial Finance, vol. 40 no. 9
Type: Research Article
ISSN: 0307-4358

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Article
Publication date: 9 February 2021

Zdzisława Elżbieta Niemczewska

The paper is to propose a tool for holistic impact assessment of commercially reused immovable cultural heritage resources on local, sustainable development along with the…

Abstract

Purpose

The paper is to propose a tool for holistic impact assessment of commercially reused immovable cultural heritage resources on local, sustainable development along with the possibility to ensure the cultural sustainability of these assets themselves. The paper contains a case study using the proposed tool. The case study concerns a historic object in the form of a Polish manor house located in rural areas in Poland adapted for commercial purposes – restaurant, painting gallery and renovation of antique furniture.

Design/methodology/approach

The author proposes a holistic approach based on aspects, to impact assessment of given heritage resources on the economic, social, cultural and environmental pillars of sustainable development and the sustainable use of heritage assets themselves. Above that, the approach proposes to use the assumptions of EMAS or ISO 14001 systems for assessment of environmental aspects in case of reused cultural heritage assets.

Findings

The test study showed that the proposed tool allows determining whether, how and to what extent the contemporary commercial function of a given element of immovable cultural heritage contributes to local sustainable development and whether and to what extent the cultural sustainability of a given cultural heritage is ensured.

Research limitations/implications

In the proposed approach, very detailed quantitative data cannot be included because of the need to simplify the research.

Practical implications

The proposed tool can be used by owners of reused historic buildings, local authorities, services responsible for the protection of cultural heritage and financing institutions to determine whether a given contemporary commercial function of cultural heritage resources contributes to local sustainable development in holistic approach and whether this function ensures the preservation of its cultural sustainability.

Social implications

The use of the proposed tool will give the opportunity to take appropriate actions to increase the impact of historic objects on local sustainable development including social aspects. Moreover, it will be possible to increase the cultural sustainability of these objects.

Originality/value

There are not many studies and tools that provide a possibility to assess a holistic impact of reused cultural heritage on local sustainable development. Research usually concerns one or two pillars: social and economic. Above that, the study of the cultural appreciation in two different groups: direct users and the local community is a novelty in the perception of contribution to cultural development. It may contribute to the different way of measurement of appreciation of cultural heritage and its contribution to social and cultural development. In addition, to study the environmental pillar, the author proposes an approach used in environmental management (ISO 1400 and EMAS), i.e. the application of activities related to eliminating the potentially harmful impact of a new function of the historic resource on the natural environment.

Details

Journal of Cultural Heritage Management and Sustainable Development, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2044-1266

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Book part
Publication date: 29 October 2018

Hassan Raza, Brad van Eeden-Moorefield, Joseph G. Grzywacz, Miriam R. Linver and Soyoung Lee

The current longitudinal study investigated the within- and between-person variance in work-to-family conflict and family-to-work conflict among working mothers over time…

Abstract

The current longitudinal study investigated the within- and between-person variance in work-to-family conflict and family-to-work conflict among working mothers over time. It also examined the effects of a nonstandard work schedule and relationship quality on work-to-family conflict and family-to-work conflict using bioecological theory. Results of multilevel modeling analyses showed that there was significant within- and between-person variance in work-to-family conflict and family-to-work conflict. The linear and quadratic terms were significantly related to family-to-work conflict, whereas the quadratic term was significantly associated with work-to-family conflict. There was also a positive relationship between a nonstandard work schedule and work-to-family conflict, whereas relationship quality was negatively associated with family-to-work conflict. Future studies should consider diversity among working mothers to adequately predict work–family conflict. The current study provides important implications for employers to consider, concerning within-and between-person differences among working mothers, which could in turn allow for accommodations and help to decrease work–family conflict.

Details

The Work-Family Interface: Spillover, Complications, and Challenges
Type: Book
ISBN: 978-1-78769-112-4

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Article
Publication date: 1 July 1997

David C. Wyld

Looks at the recent US court decision in the case of Pepsico v. Redmond. The case centred on the circumstances of Quaker’s hiring of William Redmond, a former Pepsico…

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779

Abstract

Looks at the recent US court decision in the case of Pepsico v. Redmond. The case centred on the circumstances of Quaker’s hiring of William Redmond, a former Pepsico marketing executive, to co‐ordinate the company’s distribution strategy for its newly‐acquired Snapple product line. At issue in the Redmond case was the unique question of whether or not knowledge of corporate strategy could be considered protectable proprietary information under the American incarnation of trade secret law. To understand the setting for the Redmond case, presents a brief overview of trade secret law in the USA. Then, after an examination of the facts and judicial decision in the Redmond case, concludes with a discussion of the implications of this case for marketing strategic decision making and executive recruitment in the post‐Redmond environment.

Details

Marketing Intelligence & Planning, vol. 15 no. 4
Type: Research Article
ISSN: 0263-4503

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Article
Publication date: 7 October 2014

Alexander S. Tonkoshkur and Alexander V. Ivanchenko

The purpose of this paper is to develop a generalized model of the nonlinear conductivity of varistor ceramic suitable for solving problems of prediction and control of…

Abstract

Purpose

The purpose of this paper is to develop a generalized model of the nonlinear conductivity of varistor ceramic suitable for solving problems of prediction and control of ceramic nonlinearity, stability of varistor properties.

Design/methodology/approach

The modeling of current-voltage characteristic of the intergranular barrier in metal oxide varistor ceramics is based on the development of the algorithm. It includes all the known mechanisms of electrotransfer in a wide range of voltages and currents of the current-voltage characteristics, and also takes into account the deviation of the barrier form the Schottky barrier.

Findings

The models of double Schottky barrier and double barrier of arbitrary form, as well as the algorithms for calculating the current-voltage characteristics of a single intergranular potential barrier and a separate “microvaristor” with the use of the most well-established understanding of the main mechanisms of electrical are developed. The results of current-voltage characteristics modeling correspond to the existing understanding of the nonlinear electrical conductivity varistor ceramics are based on zinc oxide. The model of double barrier of arbitrary form takes into account the deviation of the barrier form the Schottky barrier which is important in predicting the deformation of the current-voltage characteristics of the varistor products in the process of degradation.

Originality/value

The relation between the form of the current-voltage characteristic and the distribution profile of the donor concentration in the surface regions of the semiconductor crystallites constituting the intergranular potential barrier is established. The accumulation of donors in the space charge region leads to the increase in the current on the prebreakdown region of the current-voltage characteristic and the reduction of voltage corresponding to the breakdown region beginning of the current-voltage characteristic. The significant role of the interlayer in the formation of current-voltage characteristic of the intergranular potential barrier is shown.

Details

Multidiscipline Modeling in Materials and Structures, vol. 10 no. 3
Type: Research Article
ISSN: 1573-6105

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