Search results

The purpose of this study is the generation of a thorough generic heart model optimized for direct 3D printing with silicone elastomers.

The base of the model design is segmentation of CT data, followed by a generic adaption and a constructive enhancement. The model is 3D printed with silicone. An evaluation of the physical model gives indications about its benefits and weaknesses.

The results show the feasibility of a generic design while maintaining anatomical correctness and the benefit of the generic approach to quickly derive a multiplicity of healthy and pathological versions from one single model. The material properties of the silicone model are sufficient for simulation, but the results of the evaluation indicate possible improvements, as for most anatomical features, the used silicone is too hard and too stretchable.

Previous developments mostly focus on patient-specific heart models. In contrast, this study sets out to explore the possibility and benefits of a generic approach. Standardized validated models would allow comparability in surgical simulation.

Dr Wallace Rubin, international consultant on soldering technology, was recently honoured with the 1994 Environmental Protection Agency (EPA) Stratospheric Ozone Protection Award for his work in helping to bring about the elimination of chlorofluorocarbon (CFC) solvents in the world's electronics industry. He is the only individual UK recipient of the 1994 award and one of just fifty individual and corporate recipients worldwide.

The purpose of the paper is to focus on the research into components with specific thermal properties and their influences on the reflow soldering process.

After a brief introduction, the paper gives an overview of the necessity of thermal management on printed circuit boards (PCBs) and the possible effects on the manufacturing of electronic devices. In the next sections, different test boards are presented for investigations into different thermal effects during soldering. The last section deals with the influences of molded interconnected devices (MIDs) on the reflow soldering process.

The investigations show that components from the thermal management influence the reflow soldering process more or less. The highest impacts on the soldering process are from components with a thermal connection to the electrical component and its solder joint. All results from the investigations have in common that the thermal influence can only be compensated by increasing the temperature during soldering. However, this significantly increases the risk of overheating the electrical components or the PCB itself.

This paper shows only the influence of some of the effects caused by thermal management on the reflow soldering process. Furthermore, vapour phase soldering is not considered, but actual investigations are carried out on vapour phase soldering ovens as well.

Thermal management becomes more and more important with the increasing functionality of electrical components and electronic devices. This topic has been the subject of a large number of articles. However, this paper deals with influences that thermal management has on the soldering process during the manufacturing of the electronic device.

Coors Ceramics GmbH, subsidiary of Coors Ceramics Company's Electronic Products Group, has appointed Mr Viktor Fronz as its German National Accounts Manager. Mr Fronz assumed responsibility for all of Coors Ceramics' electronic products accounts in Germany on 1 July 1994.

The fiercely increasing dynamics in many industries, which are a result of globalization, are main reasons for the increasing number of alliances during the past decade. Firms foster the exploitation as well as the exploration processes by engaging in alliances. To do so, firms need specific capabilities, such as an alliance capability. This contribution aims at describing the development process of alliance capability. Alliance capability will be analyzed in this contribution on a theoretical and qualitative basis by performing a case study on a global acting financial institution, operating in a highly dynamic and coopetitive environment, the Deutsche Börse AG.

Like the conventional PCB, the Moulded Interconnect Device (MID), be it 2‐ or 3‐dimensional, will have, as its interconnection medium, conductive patterning or structuring upon the surface of the device. This interconnection pattern will, in the majority of MID products, take the form of a metal (usually copper) deposited upon the surface of the plastic. How this metal is deposited and remains attached to the surface is the critical step in the production of a MID. That is the bond, or adhesion, between plastic and the applied metal circuitry. Without a strong and reliable bond between circuitry and plastic it will not be possible to manufacture a MID with the characteristics of a conventional interconnection medium, the PCB, the technology it is probably replacing within the finished product. This paper describes the development of a chemical adhesion process, and how the selection of a suitable resin and its moulding parameters can influence the adhesion performance of the metallisation process.

One popular method to assess discriminant validity in structural equation modeling is the heterotrait-monotrait ratio of correlations (HTMT). However, the HTMT assumes tau-equivalent measurement models, which are unlikely to hold for most empirical studies. To relax this assumption, the authors modify the original HTMT and introduce a new consistent measure for congeneric measurement models: the HTMT2.

The HTMT2 is designed in analogy to the HTMT but relies on the geometric mean instead of the arithmetic mean. A Monte Carlo simulation compares the performance of the HTMT and the HTMT2. In the simulation, several design factors are varied such as loading patterns, sample sizes and inter-construct correlations in order to compare the estimation bias of the two criteria.

The HTMT2 provides less biased estimations of the correlations among the latent variables compared to the HTMT, in particular if indicators loading patterns are heterogeneous. Consequently, the HTMT2 should be preferred over the HTMT to assess discriminant validity in case of congeneric measurement models.

However, the HTMT2 can only be determined if all correlations between involved observable variables are positive.

This paper introduces the HTMT2 as an improved version of the traditional HTMT. Compared to other approaches assessing discriminant validity, the HTMT2 provides two advantages: (1) the ease of its computation, since HTMT2 is only based on the indicator correlations, and (2) the relaxed assumption of tau-equivalence. The authors highly recommend the HTMT2 criterion over the traditional HTMT for assessing discriminant validity in empirical studies.

Drawing upon the job-demands resources and the job demands-control-support model, the authors examined the buffering effect of health-oriented leadership (HoL) in terms of staff care on the relationship between job demands and employee health and job satisfaction.

Cross-sectional data from two studies (N1 = 314 and N2 = 260) were analyzed using moderation analyses.

Study 1 showed that staff care mitigates the effect of job demands on strain and health complaints. Study 2 found that staff care also buffered the effect of job demands on general health and job satisfaction.

Particularly under high job demands, staff care is an important resource for employees' health and satisfaction. Organizations should promote leaders' staff care.

Findings provide further evidence for the beneficial role of leaders in terms of HoL.

This paper aims to analyse the general effect of co-created products on the brand equity of observers (OBBE). The influence of different implementations of the co-creation approach on the OBBE is tested. It is also discussed whether co-creation can be a strategic method for companies to positively affect the OBBE in the mass market.

A between-subject experiment with a 2 (intensity of integration: democratically voted vs commonly created) × 2 (expert knowledge: no expert knowledge vs expert knowledge) design plus one control group (zero co-creation) is conducted for two brands to test the postulated hypotheses.

Co-creation can have a weak positive effect on the OBBE. Integration intensity and expertise of integrated consumer also affect the OBBE only marginally.

Further research might investigate whether the initial brand equity has a moderating effect. Also brand image and underlying product category could influence the relation between co-creation and the OBBE and would be valuable for future studies.

Brand managers should aim to convert observers into participants, instead of setting the focus on the presentation of the user-designed product to the mass market.

This study is one of the few analyzing the effects of co-creation on observers in terms of brand equity. In addition to existing research, the concept of expertise in combination with co-creation and its influence on the OBBE is explored.

Crowdsourcing – a form of collaboration across organizational boundaries – provides access to knowledge beyond an organization’s local knowledge base. Integrating work on organization theory and innovation, the authors first develop a framework that characterizes crowdsourcing into a main sequential process, through which organizations (1) define the task they wish to have completed; (2) broadcast to a pool of potential contributors; (3) attract a crowd of contributors; and (4) select among the inputs they receive. For each of these phases, the authors identify the key decisions organizations make, provide a basic explanation for each decision, discuss the trade-offs organizations face when choosing among decision alternatives, and explore how organizations may resolve these trade-offs. Using this decision-centric approach, the authors continue by showing that there are fundamental interdependencies in the process that makes the coordination of crowdsourcing challenging.