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Article
Publication date: 1 March 1986

H. Bangert, A. Kaminitschek and A. Wagendristel

Hardness testing using a SEM offers visual observation and measurement according to the hardness definition even for submicroscopic impressions. It can provide information on…

Abstract

Hardness testing using a SEM offers visual observation and measurement according to the hardness definition even for submicroscopic impressions. It can provide information on plasticity, homogeneity, adhesion etc. which cannot be obtained from depth measurements alone. The device described operates inside a SEM and offers a load between 10−2N and 10−5N. The influence of test load, rate of load increase and dwell time on the results was examined on various materials.

Details

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

Article
Publication date: 1 January 2004

Jaroslav Mackerle

This paper gives a bibliographical review of the finite element modelling and simulation of indentation testing from the theoretical as well as practical points of view. The…

2056

Abstract

This paper gives a bibliographical review of the finite element modelling and simulation of indentation testing from the theoretical as well as practical points of view. The bibliography lists references to papers, conference proceedings and theses/dissertations that were published between 1990 and 2002. At the end of this paper, 509 references are listed dealing with subjects such as, fundamental relations and modelling in indentation testing, identification of mechanical properties for specific materials, fracture mechanics problems in indentation, scaling relationship for indentation, indenter geometry and indentation testing.

Details

Engineering Computations, vol. 21 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 February 1986

The Deutscher Verband für Schweisstechnik (German Welding Society) made a very judicious and much appreciated choice of venue for its Third International Conference on 18–20…

Abstract

The Deutscher Verband für Schweisstechnik (German Welding Society) made a very judicious and much appreciated choice of venue for its Third International Conference on 18–20 February, 1986, on Interconnection Technology in Electronics. Fellbach, less than 10 km from the Schlossplatz in Stuttgart, and whose past profile was shaped almost entirely by winegrowing, has become since the opening in 1976 of the Schwabenlandhalle a town renowned equally for its significance as a conference centre. With the vine‐crowned Kappelberg hill dominating the town and commanding views to the Neckar Valley, Swabian hospitality and friendliness at its best, and a most impressive congress hall with excellent facilities in picturesque snow‐clad surroundings, the ingredients for providing a conference venue conducive to an optimum interchange of technological information were certainly present.

Details

Microelectronics International, vol. 3 no. 2
Type: Research Article
ISSN: 1356-5362

Article
Publication date: 1 September 1995

Zuu‐Chang Hong, Ching Lin and Ming‐Hua Chen

A transport equation for the one‐point velocity probability densityfunction (pdf) of turbulence is derived, modelled and solved. The new pdfequation is obtained by two modeling…

Abstract

A transport equation for the one‐point velocity probability density function (pdf) of turbulence is derived, modelled and solved. The new pdf equation is obtained by two modeling steps. In the first step, a dynamic equation for the fluid elements is proposed in terms of the fluctuating part of Navier‐Stokes equation. A transition probability density function (tpdf) is extracted from the modelled dynamic equation. Then the pdf equation of Fokker‐Planck type is obtained from the tpdf. In the second step, the Fokker‐Planck type pdf equation is modified by Lundgren’s formal pdf equation to ensure it can properly describe the turbulence intrinsic mechanism. With the new pdf equation, the turbulent plane Couette flow is solved by the direct finite difference method coupled with dimensionality reduction and QUICKER scheme. A simple boundary treatment is proposed such that the near‐wall solution is tractable and then no refined grid is required. The calculated mean velocity, friction coefficient, and turbulence structure are in good agreement with available experimental data. In the region departed from the center of flow field, the contours of isojoint pdf of V1 and V2 is very similar to that of experimental result of channel flow. These agreements show the validity of the new pdf model and the availability of the boundary treatment and QUICKER scheme for solving the turbulent plane Couette flow.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 5 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 July 2005

Mary E. Kinsella, Blaine Lilly, Benjamin E. Gardner and Nick J. Jacobs

To determine static friction coefficients between rapid tooled materials and thermoplastic materials to better understand ejection force requirements for the injection molding…

2440

Abstract

Purpose

To determine static friction coefficients between rapid tooled materials and thermoplastic materials to better understand ejection force requirements for the injection molding process using rapid‐tooled mold inserts.

Design/methodology/approach

Static coefficients of friction were determined for semi‐crystalline high‐density polyethylene (HDPE) and amorphous high‐impact polystyrene (HIPS) against two rapid tooling materials, sintered steel with bronze (LaserForm ST‐100) and stereolithography resin (SL5170), and against P‐20 mold steel. Friction tests, using the ASTM D 1894 standard, were run for all material pairs at room temperature, at typical part ejection temperatures, and at ejection temperatures preceded by processing temperatures. The tests at high temperature were designed to simulate injection molding process conditions.

Findings

The friction coefficients for HDPE were similar on P‐20 Steel, LaserForm ST‐100, and SL5170 Resin at all temperature conditions. The HIPS coefficients, however, varied significantly among tooling materials in heated tests. Both polymers showed highest coefficients on SL5170 Resin at all temperature conditions. Friction coefficients were especially high for HIPS on the SL5170 Resin tooling material.

Research limitations/implications

Applications of these findings must consider that elevated temperature tests more closely simulated the injection‐molding environment, but did not exactly duplicate it.

Practical implications

The data obtained from these tests allow for more accurate determination of friction conditions and ejection forces, which can improve future design of injection molds using rapid tooling technologies.

Originality/value

This work provides previously unavailable friction data for two common thermoplastics against two rapid tooling materials and one steel tooling material, and under conditions that more closely simulate the injection‐molding environment.

Details

Rapid Prototyping Journal, vol. 11 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 August 2003

Josef Eberhardsteiner, Günter Hofstetter, Günther Meschke and Peter Mackenzie‐Helnwein

In this paper, three research topics are presented referring to different aspects of multifield problems in civil engineering. The first example deals with long term behaviour of…

1278

Abstract

In this paper, three research topics are presented referring to different aspects of multifield problems in civil engineering. The first example deals with long term behaviour of wood under multiaxial states of stress and the effect of moisture changes on the deformation behaviour of wood. The second example refers to the application of a three‐phase model for soils to the numerical simulation of dewatering of soils by means of compressed air. The soil is modelled as a three phase‐material, consisting of the deformable soil skeleton and the fluid phases – water and compressed air. The third example is concerned with computational durability mechanics of concrete structures. As a particular example of chemically corrosive mechanisms, the material degradation due to the dissolution of calcium and external loading is addressed.

Details

Engineering Computations, vol. 20 no. 5/6
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 13 November 2007

J. Andrew Grimson and David F. Pyke

The paper seeks to develop a framework for sales and operations planning (S&OP) that is based on previous literature and company interviews. It is designed to help managers…

14792

Abstract

Purpose

The paper seeks to develop a framework for sales and operations planning (S&OP) that is based on previous literature and company interviews. It is designed to help managers understand how effective their S&OP processes are and how to progress to advanced stages.

Design/methodology/approach

The S&OP literature, is reviewed and the results of a number of company interviews are presented. These lead to a new framework, with descriptions of each stage, and to implementation insights for managers.

Findings

After highlighting key dimensions for establishing a firm's S&OP maturity on a five‐stage framework and, with the use of this framework, exploring in a preliminary way the relationship between firm size or process type (job shop, batch flow, continuous flow, etc.) and its degree of S&OP plan integration, little apparent relationship was found. However, the data suggest that business processes are enablers of S&OP plan integration, but that information technology is not clearly so.

Research limitations/implications

The results are based on a thorough review of the literature and on 15 in‐depth company interviews. Because the sample size is small, the results should be considered to provide only preliminary insights.

Practical implications

Managers can use the framework to assess their S&OP process maturity. To advance to higher S&OP integration, managers should focus on leadership of business processes that can enable effective S&OP plan integration. These processes include organizational structure, meetings and collaboration across functional areas, and performance measurements. Information technology tools may also be enablers, but they do not appear to be the primary drivers.

Originality/value

The framework separates business processes from information processes. It is quite extensive and therefore provides managers with an indication of the maturity of their S&OP processes. Also presented are insights into an intuitive, albeit challenging, process for advancing through the stages of maturity. Finally, a perspective on the future of S&OP integration is suggested that is focused on optimizing profits rather than myopically maximizing revenues or minimizing costs.

Details

The International Journal of Logistics Management, vol. 18 no. 3
Type: Research Article
ISSN: 0957-4093

Keywords

Article
Publication date: 9 November 2010

André Pretorius

The purpose of this paper is to explore the factors that contribute towards learning effectiveness in e‐learning courses. A review of previous studies was carried out to determine…

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Abstract

Purpose

The purpose of this paper is to explore the factors that contribute towards learning effectiveness in e‐learning courses. A review of previous studies was carried out to determine those factors that are most applicable to a tertiary teaching environment and to propose a model to assess effectiveness in online courses. The virtual learning environment (VLE) was defined to establish the boundaries for measurement. Constructivism was explored as a teaching approach in tertiary online courses. This model provided the input for a demonstration of an online course measurement and feedback tool using Moodle. A current student group was used to demonstrate the tool's use and recommendations were made from the findings. Areas for improvement were discussed and recommendations made for future studies.

Design/methodology/approach

In this study a literature analysis approach was followed to establish theoretical bases for the practical application of the theory. The objective of the study was to demonstrate a model to measure the effectiveness of an LMS in aiding learner success as the most important success indicator of an e‐learning system.

Findings

The demonstration of a survey tool in Moodle showed a possible method to determine preferences and measure the extent to which it was achieved in an online course. This study endeavoured to explore the factors that contribute towards improving learning effectiveness specifically in the e‐learning environment. A model was proposed with the teacher, learner and design dimensions in the constructivist approach.

Originality/value

This study sets out to answer the following questions: What is learning effectiveness and what factors influence learning effectiveness in e‐learning? What factors are significant in measuring e‐learning effectiveness at the Military Academy? And what general high‐level framework can be used to develop a measurement instrument for future positivistic studies?

Details

Campus-Wide Information Systems, vol. 27 no. 5
Type: Research Article
ISSN: 1065-0741

Keywords

Article
Publication date: 11 May 2015

Agnieszka Bielinska-Kwapisz

Given that there exists in the literature relatively little research into the effectiveness of writing centers at universities, the purpose of this paper is to show the impact of…

1632

Abstract

Purpose

Given that there exists in the literature relatively little research into the effectiveness of writing centers at universities, the purpose of this paper is to show the impact of university writing centers on first-year business seminar student writing.

Design/methodology/approach

This quantitative study involved 315 first-year undergraduate business students. Logistic and quantile regression analysis was used to test two hypotheses.

Findings

Results indicate that student intrinsic and extrinsic motivational factors positively influenced the likelihood that a student visits the center. Student grades on writing assignments were significantly higher for students who visited the writing center but only for students who scored in the top 40th percentile of the grade distribution.

Practical implications

Writing centers should try to reach all students not only those who are naturally motivated. Most importantly, centers should find ways to help students in the lower portion of grade distribution since these students presumably require sustained help.

Originality/value

This paper suggests that writing centers helped only students at the top of the grades distribution which may be valuable to universities in assessing impact of writing centers and help in the efforts to improve student writing. However, this effect can only be uncovered using quantile regression. Therefore, this research has demonstrated the potential usefulness of quantile regression as a predictive and explanatory tool in assessment.

Details

International Journal of Educational Management, vol. 29 no. 4
Type: Research Article
ISSN: 0951-354X

Keywords

Open Access
Article
Publication date: 22 January 2021

Kaja Primc, Marko Ogorevc, Renata Slabe-Erker, Tjaša Bartolj and Nika Murovec

The diversity of perspectives means that one can find many factors and models of proenvironmental behavior. However, they typically suffer from limitations and varying degrees of…

4432

Abstract

Purpose

The diversity of perspectives means that one can find many factors and models of proenvironmental behavior. However, they typically suffer from limitations and varying degrees of validity in specific contexts, suggesting that today the prime goal should be to learn and improve the models which have been already developed. In this study, the authors build on the model for predicting proenvironmental behavior developed by Oreg and Katz-Gerro (2006), namely one of the most comprehensive cross-national proenvironmental behavior models and one of the few not to be limited to either a local or single-country context or specific proenvironmental behavior.

Design/methodology/approach

By using the statistical matching technique, the authors merged data from two existing databases without common identifiers – the International Social Survey Program (environmental module) and the European Social Survey (Round 5). The resulting multinational data concerning 9,710 observations enabled a replication with extensions of Oreg and Katz-Gerro's (2006) proenvironmental behavior model that incorporates newly added Schwartz's theory of human values. To achieve the study's main objective, that is, to present improvements to the original model of proenvironmental behavior, the authors used structural equation modeling (SEM) procedures to estimate four competing models in the R program.

Findings

This study implies that Schwartz's individually measured motivational types of values (benevolence [BE], universalism [UN], self-direction [SD]) are predictors of people's proenvironmental behavior, while his conceptualization of post-materialism yields a better model fit than Inglehart's country-level post-materialism scores. The results also corroborate previous findings that post-materialist values can stimulate proenvironmental behaviors through attitudes, perceived behavioral control and intentions. The present study reveals that proenvironmental attitudes did not change substantially in the 10-year period, even though the world's environmental and sustainability challenges have largely increased. Surprisingly, the mean value of several of the perceived threat variables even decreased.

Originality/value

The authors externally validate one of the most comprehensive proenvironmental behavior models by reproducing it using new multinational large-sample data with nearly 10,000 observations collected 10 years later. The most significant addition to the original model introduced in the current study is the inclusion of Schwartz's motivational types of values, which are measured at the individual level, namely BE, UN and SD. The authors also extend the model by adding proenvironmental behavior measures and group the construct into three latent variables: saving natural resources, green purchasing and environmental activism.

Details

Baltic Journal of Management, vol. 16 no. 2
Type: Research Article
ISSN: 1746-5265

Keywords

1 – 10 of 59