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Article
Publication date: 8 May 2018

Aibin Zhu, Hongling Wu, Yulei Yang and Shengli He

Because of the various geometric descriptions of different bearing types, performance calculation of journal bearing is complicated, and is difficult in traditional model. This…

Abstract

Purpose

Because of the various geometric descriptions of different bearing types, performance calculation of journal bearing is complicated, and is difficult in traditional model. This paper aims to simplify the calculation of the journal bearing performance, and to reduce the workload.

Design/methodology/approach

On the basis of previous research, a general performance calculation model of journal bearing is proposed in this paper. Eccentricity ratio and attitude angle of axis to each pad are calculated by coordinates of spindle center and each pad center by establishing the unified coordinate system. The surface deformation of journal bearing is taken into consideration, and a correction value is added to the dimensionless oil film thickness.

Findings

The performance calculation results of various fix-pad and tilting-pad journal bearings match the results of the existing references very well, revealing the validity of the model. The general model can greatly reduce programming workload, and increase adaptability to different bearings.

Originality/value

Geometric descriptions of both fix-pad and tilting-pad journal bearings are unified in this model, which can be applied to both standard and non-standard journal bearings with different preload ratios. In addition, due to the unification of different bearings types, this model is more conducive to performance comparison among different bearing types, and promotes the development of new structural forms for journal bearings.

Details

Industrial Lubrication and Tribology, vol. 70 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Book part
Publication date: 23 October 2023

Glenn W. Harrison and Don Ross

Behavioral economics poses a challenge for the welfare evaluation of choices, particularly those that involve risk. It demands that we recognize that the descriptive account of…

Abstract

Behavioral economics poses a challenge for the welfare evaluation of choices, particularly those that involve risk. It demands that we recognize that the descriptive account of behavior toward those choices might not be the ones we were all taught, and still teach, and that subjective risk perceptions might not accord with expert assessments of probabilities. In addition to these challenges, we are faced with the need to jettison naive notions of revealed preferences, according to which every choice by a subject expresses her objective function, as behavioral evidence forces us to confront pervasive inconsistencies and noise in a typical individual’s choice data. A principled account of errant choice must be built into models used for identification and estimation. These challenges demand close attention to the methodological claims often used to justify policy interventions. They also require, we argue, closer attention by economists to relevant contributions from cognitive science. We propose that a quantitative application of the “intentional stance” of Dennett provides a coherent, attractive and general approach to behavioral welfare economics.

Details

Models of Risk Preferences: Descriptive and Normative Challenges
Type: Book
ISBN: 978-1-83797-269-2

Keywords

Article
Publication date: 12 July 2011

Omar AL‐Tabbaa and Rifat Rustom

This paper seeks to propose a general framework to be used in developing multi‐use simulation modules for estimating project durations at the planning phase.

Abstract

Purpose

This paper seeks to propose a general framework to be used in developing multi‐use simulation modules for estimating project durations at the planning phase.

Design/methodology/approach

The research method incorporates two main stages. First, conceptualisation of the general framework, and second, implementing the framework in modelling and experimenting simulation modules, which involves data collection, statistical analysis, templates building through the ARENA software, and modules verification and validation.

Findings

The framework was found to be effective in providing an approach for building multi‐use simulation modules. The validation and verification processes of the developed simulation module reflect the soundness of the proposed framework.

Practical implications

Useful insights have been presented in this research regarding building multi‐use simulation modules in infrastructure construction projects. In addition, the paper demonstrates examples about how simulation interaction interface can contribute to the efficiency of using the simulation technique.

Originality/value

Given the lack of general approaches for building multi‐use simulation modules, this research suggests a simplified approach for developing multi‐use modules. Both academics and practitioners can benefit from this new approach by understanding the mechanism behind the multi‐use model concept as explained in this paper.

Article
Publication date: 1 May 2000

Anghel N. Rugina

Presents the first chapter in this work with regard to the search for new ideas and better interpretations in the growth and development of new ideas. Investigates the exchange of…

Abstract

Presents the first chapter in this work with regard to the search for new ideas and better interpretations in the growth and development of new ideas. Investigates the exchange of views between thinkers of different points of view. Invites co‐operation between various factions to investigate unification of all known sciences (natural and economic) and to include the arts. Mentions all the great thinkers in these areas and unreservedly discusses their contribution in the school of thought. Proffers that modern technology cannot and should not be slowed down and that for the social economy of human solidarity should be aimed for, to begin a new era for humanity.

Details

International Journal of Social Economics, vol. 27 no. 5/6
Type: Research Article
ISSN: 0306-8293

Keywords

Article
Publication date: 1 March 2010

5611

Abstract

Details

Journal of Public Budgeting, Accounting & Financial Management, vol. 22 no. 3
Type: Research Article
ISSN: 1096-3367

Book part
Publication date: 6 January 2016

Michel van der Wel, Sait R. Ozturk and Dick van Dijk

The implied volatility surface is the collection of volatilities implied by option contracts for different strike prices and time-to-maturity. We study factor models to capture…

Abstract

The implied volatility surface is the collection of volatilities implied by option contracts for different strike prices and time-to-maturity. We study factor models to capture the dynamics of this three-dimensional implied volatility surface. Three model types are considered to examine desirable features for representing the surface and its dynamics: a general dynamic factor model, restricted factor models designed to capture the key features of the surface along the moneyness and maturity dimensions, and in-between spline-based methods. Key findings are that: (i) the restricted and spline-based models are both rejected against the general dynamic factor model, (ii) the factors driving the surface are highly persistent, and (iii) for the restricted models option Δ is preferred over the more often used strike relative to spot price as measure for moneyness.

Article
Publication date: 5 May 2015

Philip Hyland

The purpose of this paper is to introduce the reader to the nature of confirmatory bifactor modelling. Confirmatory bifactor modelling is a factor analytic procedure that allows…

Abstract

Purpose

The purpose of this paper is to introduce the reader to the nature of confirmatory bifactor modelling. Confirmatory bifactor modelling is a factor analytic procedure that allows researchers to model unidimensionality and multidimensionality simultaneously. This method has important applications in the field of criminal psychology.

Design/methodology/approach

This paper begins by introducing the topic of factor analysis and explains how confirmatory bifactor modelling is similar yet distinct to the more familiar factor analytical procedures in the psychological literature.

Findings

Through practical examples this paper explains the value of this analytical technique to researchers in criminal psychology. Examples from the existing criminal psychological literature are used to illustrate the way in which bifactor analysis allows important theoretical questions to be addressed.

Originality/value

This paper highlights the strengths and limitations associated with traditional “restricted” confirmatory bifactor models and introduces the notion of the “unrestricted” bifactor model. The unrestricted bifactor model allows greater flexibility for addressing interesting research questions. The paper concludes by providing the reader with an annotated Mplus syntax file for how to perform confirmatory bifactor modelling.

Abstract

Details

Handbook of Microsimulation Modelling
Type: Book
ISBN: 978-1-78350-570-8

Content available
Book part
Publication date: 1 January 2001

Abstract

Details

Dynamic General Equilibrium Modelling for Forecasting and Policy: A Practical Guide and Documentation of MONASH
Type: Book
ISBN: 978-0-44451-260-4

Article
Publication date: 6 November 2017

Shamindra Nath Sanyal, Saroj Kumar Datta and Asok Kumar Banerjee

The purpose of this paper is to examine the physicians’ attitude toward branded generic drugs in prescribing those drugs in some selective medical conditions and to identify the…

Abstract

Purpose

The purpose of this paper is to examine the physicians’ attitude toward branded generic drugs in prescribing those drugs in some selective medical conditions and to identify the factors that influence physicians’ behavior toward prescribing branded generic drugs in the said selective medical conditions.

Design/methodology/approach

The study was carried out across six major cities in eastern India with 301 physicians. The current study introduced some significant elements into the modified technology acceptance model (TAM) with title the extended tam for product usage (TETPU) to analyze the prescribing factors that influence physicians in five common yet serious medical conditions in India. Out of nine factors considered here, seven were selected from the previous literature studies of different product segments and two were proposed by the authors. Demographic factor was proposed as the confounding variable.

Findings

The results indicated that apart from the factors “perceived no need” and “physicians’ perception and need achievement” rest of the factors showed satisfactory to excellent results.

Practical implications

The current study findings may enable the pharmaceutical managers to revise or modify their current marketing communication and other brand-building strategies so as to achieve a superior performance that offers them a competitive advantage.

Originality/value

The paper fulfils a need for advancing the knowledge on the physician’s prescription influencing factors by introducing the newer aspects of the concept and offers a theoretical framework for the academia and practical framework for the managers who desire to implement the strategies to achieve competitive advantage.

Details

International Journal of Pharmaceutical and Healthcare Marketing, vol. 11 no. 4
Type: Research Article
ISSN: 1750-6123

Keywords

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