Michael Rosenthal, Markus Rüggeberg, Christian Gerber, Lukas Beyrich and Jeremy Faludi
The purpose of this study is to quantify the vertical shrinkage rates and the mechanical strength of three-dimensional (3D) printed parts for a variety of wood-based materials for…
Abstract
Purpose
The purpose of this study is to quantify the vertical shrinkage rates and the mechanical strength of three-dimensional (3D) printed parts for a variety of wood-based materials for liquid deposition modeling.
Design/methodology/approach
The overall hypothesis was that a well-chosen combination of binders, fibers and fillers could reduce shrinkage in the Z dimension and increase compressive and flexural strength (DIN 52185, 52186). To test this assumption, eight sub-hypotheses were formulated. Mixtures of the ingredients were chosen in different ratios to measure the performance of prints. For time efficiency, an iterative heuristic approach was used – not testing all variations of all variables in even increments, but cutting off lines of testing when mixtures were clearly performing poorly.
Findings
The results showed that some mixtures had high dimensional accuracy and strength, while others had neither, and others had one but not the other. Shrinkage of 3D printed objects was mainly caused by water release during drying. An increase of the wood as well as the cement, sand, salt and gypsum content led to reduced vertical shrinkage, which varied between 0 and 23%. Compressive and flexural strength showed mixed trends. An increase in wood and salt content worsened both strength properties. The addition of fibers improved flexural, and the addition of cement improved compression strength. The highest strength values of 14 MPa for compressive and 8 MPa for flexural strength were obtained in the test series with gypsum.
Originality/value
This paper is an important milestone in the development of environmentally friendly materials for additive manufacturing. The potential of many ingredients to improve physical properties could be demonstrated.
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Dawne Moon and Theresa W. Tobin
Scholars who study humility tend to think of it in highly individualized terms, such as an absence of vanity or an accurate self-assessment. Individuating definitions can lead to…
Abstract
Scholars who study humility tend to think of it in highly individualized terms, such as an absence of vanity or an accurate self-assessment. Individuating definitions can lead to such jarring concepts as the “humble white supremacist” (Roberts & Wood, 2007). Qualitative sociological research in the (predominantly North American) evangelical movement to accept and affirm lesbian, gay, bisexual, trans, queer, and intersex (LGBTQI) identities, same-sex marriage, and sex/gender transition reveals that humility is not simply the awareness that “I could be wrong.” That awareness is rooted in what we have found to be humility’s defining element, concern to foster relationship. These findings prompt us to define humility as a fundamentally social disposition, as concern to protect the kinds of intimate connection with others that can transform the self. Recognizing the social nature of humility reveals why humility is incompatible with injustice.
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Flavio Felice and Massimiliano Vatiero
It is often “assumed,” even among well-informed lawyers and economists, that European competition law is an emulation of the US antitrust law because of American influence on…
Abstract
It is often “assumed,” even among well-informed lawyers and economists, that European competition law is an emulation of the US antitrust law because of American influence on European political and economic debates after the Second World War. However, such an assumption is disputable: in accordance with Professor Gerber, the competition law in Europe is an indigenous product based primarily on ideas developed in Germany by the so-called ordoliberal thought. In this respect, the article 102 TFEU may be considered a proof. The aims of this article are to furnish a critical examination of ordoliberal ideas of anticompetitive conducts and underline the relevance of ordoliberal thought for the development of the modern European competition law.
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Lars Mjøset, Roel Meijer, Nils Butenschøn and Kristian Berg Harpviken
This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial…
Abstract
This study employs Stein Rokkan's methodological approach to analyse state formation in the Greater Middle East. It develops a conceptual framework distinguishing colonial, populist and democratic pacts, suitable for analysis of state formation and nation-building through to the present period. The framework relies on historical institutionalism. The methodology, however, is Rokkan's. The initial conceptual analysis also specifies differences between European and the Middle Eastern state formation processes. It is followed by a brief and selective discussion of historical preconditions. Next, the method of plotting singular cases into conceptual-typological maps is applied to 20 cases in the Greater Middle East (including Afghanistan, Iran and Turkey). For reasons of space, the empirical analysis is limited to the colonial period (1870s to the end of World War 1). Three typologies are combined into one conceptual-typological map of this period. The vertical left-hand axis provides a composite typology that clarifies cultural-territorial preconditions. The horizontal axis specifies transformations of the region's agrarian class structures since the mid-19th century reforms. The right-hand vertical axis provides a four-layered typology of processes of external intervention. A final section presents selected comparative case reconstructions. To the authors' knowledge, this is the first time such a Rokkan-style conceptual-typological map has been constructed for a non-European region.
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Lili Liu, Ayoung Suh and Christian Wagner
Researchers have called for the synthesis of divergent perspectives and the development of a theoretical model that examines individuals’ donation behavior in charitable…
Abstract
Purpose
Researchers have called for the synthesis of divergent perspectives and the development of a theoretical model that examines individuals’ donation behavior in charitable crowdfunding. To fill this research gap, the purpose of this paper is to synthesize the literature pertaining to the determinants of donation behavior in charitable crowdfunding. Then, drawing on the stimulus-organism-response framework, the authors develop and test a model that explains individuals’ intention to donate to charitable crowdfunding.
Design/methodology/approach
This paper follows a quantitative research approach. An online survey was distributed to collect data from individuals who had experienced charitable crowdfunding. In total, 205 valid responses were received and analyzed.
Findings
First, this study finds that individuals’ empathy and the perceived credibility of a charitable crowdfunding project are key determinants for their intention to donate in charitable crowdfunding. Second, the study finds that website quality, transaction convenience, and project content quality influence both empathy and perceived credibility in different ways. Third, it is noteworthy that initiator reputation is positively related to perceived credibility, while project popularity is positively associated with empathy.
Originality/value
This research advances the knowledge of individual donation behavior in charitable crowdfunding. The model can help researchers understand individuals’ philanthropic behavior by providing empirical explanations of the interplay between technological and project characteristics, emotional and cognitive states, and individuals’ donation behavior. For practitioners, the research suggests appropriate design, launch, and operation strategies to facilitate individuals’ donation behavior in charitable crowdfunding.
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At the nexus of social movement and organizational studies is the question of how social movements matter to organizational processes, such as how anticorporate activism impacts…
Abstract
At the nexus of social movement and organizational studies is the question of how social movements matter to organizational processes, such as how anticorporate activism impacts corporations, markets, and industries. This chapter presents a framework for better answering this question. The chapter suggests that the contentious and private politics literature should be brought closer together to understand this phenomenon. Drawing on the concepts of scale shift and the political, industry, and corporate opportunity structures, the chapter illustrates how the contentious politics literature can be adjusted to help explain the outcomes of private politics.
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Thomas Preisner, Christian Bolzmacher, Andreas Gerber, Karin Bauer, Eckhard Quandt and Wolfgang Mathis
The purpose of this paper is to investigate the accuracy of different force calculation methods and their impact on mechanical deformations. For this purpose, a micrometer scaled…
Abstract
Purpose
The purpose of this paper is to investigate the accuracy of different force calculation methods and their impact on mechanical deformations. For this purpose, a micrometer scaled actuator is considered, which consists of a micro‐coil and of a permanent magnet (PM) embedded in a deformable elastomeric layer.
Design/methodology/approach
For the magnetic field evaluation a hybrid numerical approach (finite element method/boundary element method (FEM/BEM) coupling and a FEM/BEM/Biot‐Savart approach) is used, whereas FEM is implemented for the mechanical deformation analysis. Furthermore, for the magneto‐mechanical coupling several force calculation methods, namely the Maxwell stress tensor, the virtual work approach and the equivalent magnetic sources methods, are considered and compared to each other and to laboratory measurements.
Findings
The numerically evaluated magnetic forces and the measured ones are in good accordance with each other with respect to the normal force acting on the PM. Nevertheless, depending on the used method the tangential force components differ from each other, which leads to slightly different mechanical deformations.
Research limitations/implications
Since the force calculations are compared to measurement data, it is possible to give a suggestion about their applicability. The mechanical behavior of the actuator due to the acting forces is solely calculated and therefore only an assumption concerning the deformation can be given.
Originality/value
A new kind of micrometer scaled actuator is numerically investigated by using two different hybrid approaches for the magnetic field evaluation. Based on those, the results of several force calculation methods are compared to measurement data. Furthermore, a subsequent structural analysis is performed, which shows slightly different mechanical deformations depending on the used force calculation method.
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Anna Kadefors, Kirsi Aaltonen, Stefan Christoffer Gottlieb, Ole Jonny Klakegg, Pertti Lahdenperä, Nils O.E. Olsson, Lilly Rosander and Christian Thuesen
Relational contracting is increasingly being applied to complex and uncertain construction projects. However, it has proved hard to achieve stable performance and industry-level…
Abstract
Purpose
Relational contracting is increasingly being applied to complex and uncertain construction projects. However, it has proved hard to achieve stable performance and industry-level learning in this field. This paper employs an institutional perspective to analyze how legitimacy for relational contracting has been produced and challenged in Denmark, Finland, Norway and Sweden, including implications for dissemination and learning.
Design/methodology/approach
A collaborative case study design is used, where longitudinal accounts of the developments in relational contracting over more than 25 years in four Nordic countries were developed by scholars based in each country. The descriptions are underpinned by literature sources from research, practice and policy.
Findings
The countries share similar problem perceptions that have triggered the de-institutionalization of traditional contracting practices. Models and policies developed elsewhere are important sources of knowledge and legitimacy. Most countries have seen pendulum movements, where dissemination of relational contracting is followed by backlashes when projects fail to meet projected outcomes. Before long, however, relational contracting tends to re-emerge under new labels and in slightly new forms. Such a proliferation of concepts presents further obstacles to learning. Successful institutionalization is found to rely on realistic goals in combination with broad competence development at the organizational and industry levels.
Practical implications
In seeking inspiration from other countries, policymakers should go beyond contract models to also consider strategies to manage industry-level learning.
Originality/value
The paper provides a unique longitudinal cross-country perspective on the field of relational contracting. As such, it contributes to the small stream of literature on long-term institutional change in the construction sector.
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Mark Breecheen and Brian H. Kleiner
Investigates religious discrimination (RD) and how this is difficult to contend with in the workplace with particular emphasis on the USA – as it has over 239 officially…
Abstract
Investigates religious discrimination (RD) and how this is difficult to contend with in the workplace with particular emphasis on the USA – as it has over 239 officially recognized sectors and approximately 1,300 unconventional groups alone! Gives examples of litigation between employee and employer and the courts’ verdicts. Shows that there are numerous factors involved in the upswing of RD cases in the USA, but to solve the complex problem the USA needs to define its stance regarding religion.
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The crowdfunding market has experienced rapid growth in recent years. However, not all projects are successfully financed because of information asymmetries between the founder…
Abstract
Purpose
The crowdfunding market has experienced rapid growth in recent years. However, not all projects are successfully financed because of information asymmetries between the founder and the providers of external finance. This shortfall in funding has made factors that lead to successful fundraising, a great interest to researchers. This study draws on the social capital theory, human capital theory and level of processing (LOP) theory to predict the success of crowdfunding projects.
Design/methodology/approach
A feature set is extracted and correlations between project success and features are utilized to order the features. The artificial neural network (ANN) is popularly applied to analyze the dependencies of the input variables to improve the accuracy of prediction. However, the problem of overfitting may exist in such neural networks. This study proposes a neural network method based on ensemble machine learning and dropout methods to generate several neural networks for preventing the problem of overfitting. Four machine learning techniques are applied and compared for prediction performance.
Findings
This study shows that the success of crowdfunding projects can be predicted by measuring and analyzing big data of social media activity, human capital of funders and online project presentation. The ensemble neural network method achieves highest accuracy. The investments rose from early projects and another platform by the funder serve as credible indicators for later investors.
Practical implications
The managerial implication of this study is that the project founders and investors can apply the proposed model to predict the success of crowdfunding projects. This study also identifies the most influential features that affect fundraising outcomes. The project funders can use these features to increase the successful opportunities of crowdfunding project.
Originality/value
This study contributes to apply a new machine learning modeling method to extract features from activity data of crowdfunding platforms and predict crowdfunding project success. In addition, it contributes to the research on the deployment of social capital, human capital and online presentation strategies in a crowdfunding context as well as offers practical implications for project funders and investors.