About the change of flow factors during the run-in process of lubricated contacts

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Achill Holzer ◽  
Katharina Schmitz
Keyword(s):  
Shear Flow ◽  
Surface Structure ◽  
Design Methodology ◽  
Test Bench ◽  
Flat Surface ◽  
Measured Data ◽  
Content Type ◽  
Lubricated Contacts ◽  
Digital Microscope ◽  
Experimental Test Bench

Purpose This paper aims to increase the knowledge of the run-in process of lubricated contacts in hydraulical pumps. When performing EHL simulations of tribological contacts, the surface influence needs to be taken into account. This experimental measurement wants to investigate the amount of change of the flow factors in the first hour of run of tribological contacts. Design/methodology/approach An experimental test bench is used to run-in several samples. After several minutes of running, samples are removed and the surface structure is captured using a digital microscope. With the measured data, flow factors are calculated. Findings The findings were clear that flow factors are highly direction-dependent, especially shear flow factors in radial directions experience almost no change. Overall, influence of the surface structure of up to 30% compared to a flat surface can be registered. Originality/value This paper helps to choose application-oriented values for the simulation of tribological contacts.

Design of a brushless excitation system utilizing pot cores

2015 ◽  
Vol 34 (6) ◽  
pp. 1740-1757
Author(s):  
Julian Veitengruber ◽  
Frank Rinderknecht ◽  
Horst E. Friedrich
Keyword(s):  
Design Methodology ◽  
Measured Data ◽  
Prototype System ◽  
Transfer System ◽  
Excitation System ◽  
Inductive Power Transfer ◽  
Content Type ◽  
Slip Rings ◽  
Brushless Excitation ◽  
System Compensation

Purpose – The purpose of this paper is to devote the optimal substitution of slip rings through an inductive power transfer system for field winding supply of generators or motors with a wound rotor. By a rotational pot-core transformer approach, the rotor-side energizing of the excitation windings can be provided isolated and free of wear. Design/methodology/approach – For design purpose, an analytical model of the inductive link and the compensation network elements is shown. Based on a pot-core transformer approach, possible types of compensation networks regarding motor-specific constraints were carried out and compared among themselves by parameter studies. The analytical parts of the model were subsequently validated with measured data of an appropriate core and accompanying FEM calculations. On the basis of an experimental prototype system, the approach has been tested both stationary and transient. Findings – The publication exemplifies how a brushless excitation system for generators and motors can be inexpensively designed and implemented. Originality/value – This paper systematically presents a comprehensive analytical approach for brushless excitation systems as well as a prototypical system. Compensation network elements regarding motor-specific constraints were carried out and compared among themselves by parameter studies.

Influence of the cavities on the PCB mechanical properties

Circuit World ◽  
2015 ◽  
Vol 41 (2) ◽  
pp. 76-79
Author(s):  
Boleslav Psota ◽  
Alexandr Otáhal ◽  
Ivan Szendiuch
Keyword(s):  
Mechanical Properties ◽  
Resonant Frequency ◽  
Design Methodology ◽  
Printed Circuit Boards ◽  
Measured Data ◽  
Circuit Boards ◽  
Frequency Range ◽  
Content Type ◽  
Printed Circuit ◽  
Acceleration Amplitude

Purpose – The main aim of this paper is to investigate the influence of the cavity coverage on the printed circuit boards (PCB) to the resonant frequency, acceleration and displacement. Design/methodology/approach – Tests were realized on four PCBs with different cavity areas. Frequency range of tests was between 10 and 2,000 Hz with 0.3 g acceleration amplitude. In addition, more simulations were performed to check different setups of the boards. Findings – From the calculated and measured data, it is clear that with the larger cavity area the resonance frequency drops. In case a greater number of components placed in cavities are needed on board, it is appropriate to use multiple smaller cavities than the bigger ones. Originality/value – Results in this paper could be very useful for PCB manufacturers and designers during designing of the new PCBs with cavities for dipped components.

Combined heat treatment of metal materials

2016 ◽  
Vol 35 (4) ◽  
pp. 1450-1459 ◽  
Author(s):  
Václav Kotlan ◽  
Roman Hamar ◽  
David Pánek ◽  
Ivo Doležel
Keyword(s):  
Heat Treatment ◽  
Numerical Solution ◽  
Design Methodology ◽  
Measured Data ◽  
Temperature Gradients ◽  
Comsol Multiphysics ◽  
Content Type ◽  
Coupled Problem ◽  
Field Temperature ◽  
Metal Materials

Purpose – The purpose of this paper is to propose and analyze a combined heat treatment of metal materials, consisting in classic induction pre-heating and/or post-heating and full heating by laser beam. This technology is prospective for some kinds of surface hardening and welding because its application leads to lowering of temperature gradients at the heated spots, which substantially reduces local residual mechanical strains and stresses. Design/methodology/approach – The task was solved like the 3D hard-coupled problem for electromagnetic field, temperature field and field of displacements. It was solved numerically using the techniques based on the FEM. For solution was used commercial software COMSOL Multiphysics, some parts were solved using own scripts in the software Agros. Findings – In the paper are shown results of the numerical solution and experimental measured data. Due the work the authors found that the influence of the pre-heating and post-heating really leads to limit the temperature gradients and from other measurements is clear that also to improving of the welding. Originality/value – The paper presents fully 3D nonlinear and nonstationary mathematical model of hybrid laser welding, its numerical solution experimental verification.

scholarly journals Vulnerable adults in police custody

2019 ◽  
Vol 22 (1) ◽  
pp. 5-8
Author(s):  
Ian Cummins
Keyword(s):  
Design Methodology ◽  
Research Literature ◽  
Police Custody ◽  
England And Wales ◽  
Content Type ◽  
Increased Risk ◽  
Vulnerable Adults

Purpose The purpose of this paper is to discuss the recent National Appropriate Adult Network (NAAN) report on the role of the appropriate adult. Design/methodology/approach This paper is based on the NAAN report and a review of relevant policy and research literature. Findings There to Help 2 highlights that there are still significant gaps in the provision of appropriate adult schemes across England and Wales. These gaps potentially place vulnerable adults at increased risk. Originality/value This paper is a review of recent research.

Co-workers’ perceptions of and reactions to employee’s involuntary demotion

2019 ◽  
Vol 41 (4) ◽  
pp. 740-757 ◽  
Author(s):  
Sophie Hennekam ◽  
Subramaniam Ananthram ◽  
Steve McKenna
Keyword(s):  
Design Methodology ◽  
Emotional Responses ◽  
Emotional Reaction ◽  
Content Type ◽  
Informational Justice ◽  
Behavioural Responses ◽  
Behavioural Reaction ◽  
Three Stages ◽  
Depth Interviews ◽  
The Way

Purpose The purpose of this paper is to investigate how individuals perceive and react to the involuntary demotion of a co-worker in their organisation. Design/methodology/approach The authors draw on 46 semi-structured in-depth interviews (23 dyads) with co-workers of demoted individuals. Findings The findings suggest that an individual’s observation of the demotion of a co-worker has three stages: their perception of fairness, their emotional reaction and their behavioural reaction. The perception of fairness concerned issues of distributive, procedural, interpersonal and informational justice. The emotional responses identified were feelings of disappointment/disillusion, uncertainty, vulnerability and anger. Finally, the behavioural reactions triggered by their emotional responses included expressions of voice, loyalty, exit and adaptation. Originality/value Perceptions of (in)justice perpetrated on others stimulate emotional and behavioural responses, which impacts organisational functioning. Managers should therefore pay attention to the way a demotion is perceived, not only by those directly concerned, but also by co-workers as observers.

Consumer value creation through WhatsApp use

2019 ◽  
Vol 32 (4) ◽  
pp. 455-471
Author(s):  
Jorge Cruz-Cárdenas ◽  
Jorge Guadalupe-Lanas ◽  
Ekaterina Zabelina ◽  
Andrés Palacio-Fierro ◽  
Margarita Velín-Fárez ◽  
...  
Keyword(s):  
Latin American ◽  
Value Creation ◽  
Emotional Support ◽  
Design Methodology ◽  
Instant Messaging ◽  
Role Performance ◽  
Content Type ◽  
Consumer Value ◽  
Depth Interviews ◽  
Practical Implications

Purpose The purpose of this paper is to understand in-depth how consumers create value in their lives using WhatsApp, the leading mobile instant messaging (MIM) application. Design/methodology/approach The study adopts the perspective of customer-dominant logic (CDL) and uses a qualitative multimethod design involving 3 focus groups and 25 subsequent in-depth interviews. The research setting was Ecuador, a Latin American country. Findings Analysis and interpretation of the participants’ stories made it possible to identify and understand the creation of four types of value: maintaining and strengthening relationships; improving role performance; emotional support; and entertainment and fun. In addition, the present study proposes a conceptual model of consumer value creation as it applies to MIM. Practical implications Understanding the way consumers create value in their lives using MIM is important not only for organizations that offer MIM applications, but also for those companies that develop other applications for mobile phones or for those who wish to use MIM as an electronic word-of-mouth vehicle. Originality/value The current study is one of the first to address the topic of consumer behavior in the use of technologies from the perspective of CDL; this perspective enables an integrated qualitative vision of value creation in which the consumer is the protagonist.

scholarly journals Advantages and potential challenges of data management in e-maintenance

2019 ◽  
Vol 25 (3) ◽  
pp. 378-396 ◽  
Author(s):  
Arian Razmi-Farooji ◽  
Hanna Kropsu-Vehkaperä ◽  
Janne Härkönen ◽  
Harri Haapasalo
Keyword(s):  
Data Management ◽  
Design Methodology ◽  
Management Practices ◽  
Future Research ◽  
Conceptual Approach ◽  
Content Type ◽  
Different Types ◽  
Maintenance Systems ◽  
Industry Leader ◽  
Practical Implications

Purpose The purpose of this paper is twofold: first, to understand data management challenges in e-maintenance systems from a holistically viewpoint through summarizing the earlier scattered research in the field, and second, to present a conceptual approach for addressing these challenges in practice. Design/methodology/approach The study is realized as a combination of a literature review and by the means of analyzing the practices on an industry leader in manufacturing and maintenance services. Findings This research provides a general understanding over data management challenges in e-maintenance and summarizes their associated proposed solutions. In addition, this paper lists and exemplifies different types and sources of data which can be collected in e-maintenance, across different organizational levels. Analyzing the data management practices of an e-maintenance industry leader provides a conceptual approach to address identified challenges in practice. Research limitations/implications Since this paper is based on studying the practices of a single company, it might be limited to generalize the results. Future research topics can focus on each of mentioned data management challenges and also validate the applicability of presented model in other companies and industries. Practical implications Understanding the e-maintenance-related challenges helps maintenance managers and other involved stakeholders in e-maintenance systems to better solve the challenges. Originality/value The so-far literature on e-maintenance has been studied with narrow focus to data and data management in e-maintenance appears as one of the less studied topics in the literature. This research paper contributes to e-maintenance by highlighting the deficiencies of the discussion surrounding the perspectives of data management in e-maintenance by studying all common data management challenges and listing different types of data which need to be acquired in e-maintenance systems.

An exploratory empirical study of whistleblowing and whistleblowers

2020 ◽  
Vol 27 (3) ◽  
pp. 755-770
Author(s):  
Maria Krambia-Kapardis
Keyword(s):  
Statistical Analysis ◽  
Design Methodology ◽  
Research Topic ◽  
Due Date ◽  
Content Type ◽  
Unethical Behaviour ◽  
Eu Member States ◽  
European Directive ◽  
Original Survey ◽  
Practical Implications

Purpose The purpose of this study is to develop a profile of whistleblowers and to determine whether whistleblowing legislation would encourage those individuals to bring to light some illegal or unethical behaviour that otherwise would remain in the shadows. Design/methodology/approach Having identified whistleblowing correlation, a survey was carried out in Cyprus of actual whistleblowers and could-have-been whistleblowers. Findings Males between 46 and55 years of age, regardless of whether they have dependents or hold senior positions in organizations are significantly more likely to blow the whistle. However, could-have-been whistleblowers did not go ahead because they felt that the authorities would not act on their information. Research limitations/implications Because of the sensitive nature of the research topic and the fact that only whistleblowers or intended whistleblowers could participate in the study, the sample size is limited as a result. This, in turn, limits both the number of respondents in each category (actual and intended) as well as constrains the statistical analysis that could be carried out on the data. Practical implications It remains to be seen whether EU Member States shall implement the European Directive 2019/1937 on the protection of persons who report breaches of Union Law, in its entirety by the due date, namely December 2021. Originality/value This study provides a literature review of whistleblowing and reports an original survey against the backdrop of the European Directive.

Interest rate option hedging portfolios without bank account

2019 ◽  
Vol 37 (1) ◽  
pp. 134-142
Author(s):  
Alberto Bueno-Guerrero
Keyword(s):  
Design Methodology ◽  
Contingent Claim ◽  
Necessary And Sufficient Condition ◽  
Barrier Option ◽  
Bank Account ◽  
Content Type ◽  
Option Hedging ◽  
Hedging Portfolio ◽  
Necessary And Sufficient ◽  
First Time

Purpose This paper aims to study the conditions for the hedging portfolio of any contingent claim on bonds to have no bank account part. Design/methodology/approach Hedging and Malliavin calculus techniques recently developed under a stochastic string framework are applied. Findings A necessary and sufficient condition for the hedging portfolio to have no bank account part is found. This condition is applied to a barrier option, and an example of a contingent claim whose hedging portfolio has a bank account part different from zero is provided. Originality/value To the best of the authors’ knowledge, this is the first time that this issue has been addressed in the literature.

Understanding decoupling in response to corporate governance reform pressures

2015 ◽  
Vol 23 (4) ◽  
pp. 369-382 ◽  
Author(s):  
Mario Krenn
Keyword(s):  
Corporate Governance ◽  
Design Methodology ◽  
Good Governance ◽  
Regulatory Change ◽  
Compliance Monitoring ◽  
Governance Reform ◽  
Firm Level ◽  
Content Type ◽  
Good Corporate Governance ◽  
Actual Use

Purpose – The purpose of this article is to explain under what circumstances firm-level adoption of codes of good corporate governance will more likely be superficial rather than substantive in nature. The article contains lessons for any agency or country that attempts to implement deep and lasting changes in corporate governance via codes of good corporate governance. Design/methodology/approach – The article reviews the literature on compliance with codes of good corporate governance and develops a conceptual model to explain why some firms that have formally adopted a code of good governance decouple this policy from its actual use. Findings – Decoupling in response to the issuance of codes of good corporate governance will be more attractive to firms and also more sustainable under the following conditions: firms’ compliance costs are relatively high firms’ costs of outright and visible non-compliance are relatively high and outsiders’ compliance monitoring costs are relatively high. Originality/value – The article contributes to the debate on compliance and convergence and provides policymakers with a conceptual framework for assessing the likelihood of successful regulatory change in corporate governance.

Sign in / Sign up

Export Citation Format

Share Document