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Metal laser-powder-bed-fusion using laser-beam parts are particularly susceptible to contamination due to particles attached to the surface. This may compromise so-called technical cleanliness (e.g. in NASA RPTSTD-8070, ASTM G93, ISO 14952 or ISO 16232), which is important for many 3D-printed components, such as implants or liquid rocket engines. The purpose of the presented comparative study is to show how cleanliness is improved by design and different surface treatment methods.

Convex and concave test parts were designed, built and surface-treated by combinations of media blasting, electroless nickel plating and electrochemical polishing. After cleaning and analysing the technical cleanliness according to ASTM and ISO standards, effects on particle contamination, appearance, mass and dimensional accuracy are presented.

Contamination reduction factors are introduced for different particle sizes and surface treatment methods. Surface treatments were more effective for concave design features, however, the initial and resulting absolute particle contamination was higher. Results further indicate that there are trade-offs between cleanliness and other objectives in design. Design guidelines are introduced to solve conflicts in design when requirements for cleanliness exist.

This paper recommends designing parts and corresponding process chains for manufacturing simultaneously. Incorporating post-processing characteristics into the design phase is both feasible and essential. In the experimental study, electroless nickel plating in combination with prior glass bead blasting resulted in the lowest total remaining particle contamination. This process applied for cleanliness is a novelty, as well as a comparison between the different surface treatment methods.

Reviews the Essen Schweissen und Schneiden cutting and welding trade show, identifies mounting trend for electric servo guns to replace pneumatic welding guns, reports on growing interest in aluminium welding and outlines the different solutions proposed, assesses the latest developments in remote laser welding technology.

The purpose of this paper is to explore how consumers perceive, experience and engage with the art of filmmaking and the industrial film production process that the film studios present to them during their guided film studio tours.

Drawing on the author’s own film tourist experiences, observations and participatory interactions with fellow visitors at a major Hollywood film studio, this paper takes an autoethnographic “I’m-the-camera”-perspective and a hermeneutic data analysis approach.

The findings reveal that visitors experience the “authentic” representation of the working studio’s industrial film production process as an opportunity and “invitation to join” a broader filmmaker community and to share their own amateur filmmaking experiences with fellow visitors and professionals – just to discover eventually that the perceived community is actually the real “simulacrum”.

Although using an autoethnographic approach means that the breadth of collected data is limited, the gain in depth of insights allows for a deeper understanding of the actual visitor experience.

The findings encourage film studio executives, managers and talent agents to reconsider current practices and motivations in delivering film studio tours and to explore avenues for harnessing their strategic potential.

Contrary to previous studies that have conceptualised film studio tours as simulacra that deny consumers a genuine access to the backstage, the findings of this study suggest that the real simulacrum is actually the film tourists’ “experienced feeling” of having joined and being part of a filmmaker community, which raises question regarding the study of virtual communities.

The purpose of this paper is to demonstrate an inverse problem approach for the determination of stress zones in steel plates of electrical machines. Steel plates of electrical machines suffer large mechanical stress by processes like cutting or punching during the fabrication. The mechanical stress has effects on the electrical properties of the steel, and thus on the losses of the machine.

In this paper, the authors present a sensor arrangement and an appropriate algorithm for determining the spatial permeability distribution in steel plates. The forward problem for stress zone imaging is explained and an appropriate numerical solution technique is proposed. Then an inverse problem formulation is introduced and the nature of the problem is analyzed.

Based on sensitivity analysis, different measurement procedures are compared and a measurement setup is suggested. Further the ill‐posed nature of the inverse problem is analyzed by the Picard condition.

Because of the increased losses due to stress zones, the quantification of stress effects is of interest to adjust the production process. Stress zone imaging is a first approach for the application of an imaging system to quantify these material defects.

This paper presents a simulation study about the applicability of an inverse problem for stress zone imaging and presents first reconstruction results. Further, the paper discusses several issues about stress zone imaging for the ongoing research.

The purpose of this paper is to present methods for dissipating heat from RF circuit boards.

The paper describes various models developed by RUWEL in this respect.

The integration of heat removal systems in the structure of printed circuit boards is a proven and reliable technique, and ideally suitable for RF circuit boards.

In addition to using conductive adhesive films to bond RF circuit boards to heat sinks, new methods have been developed to integrate local heat removal systems in the form of Cu coins. These techniques give the circuit designer flexibility in terms of board design and choice of materials. The models presented are already being used for various RF components in base stations for cellular telephone networks and WiMax services.

This study aims to provide a comprehensive overview of the current state of the art in powder bed fusion (PBF) techniques for additive manufacturing of multiple materials. It reviews the emerging technologies in PBF multimaterial printing and summarizes the latest simulation approaches for modeling them. The topic of “multimaterial PBF techniques” is still very new, undeveloped, and of interest to academia and industry on many levels.

This is a review paper. The study approach was to carefully search for and investigate notable works and peer-reviewed publications concerning multimaterial three-dimensional printing using PBF techniques. The current methodologies, as well as their advantages and disadvantages, are cross-compared through a systematic review.

The results show that the development of multimaterial PBF techniques is still in its infancy as many fundamental “research” questions have yet to be addressed before production. Experimentation has many limitations and is costly; therefore, modeling and simulation can be very helpful and is, of course, possible; however, it is heavily dependent on the material data and computational power, so it needs further development in future studies.

This work investigates the multimaterial PBF techniques and discusses the novel printing methods with practical examples. Our literature survey revealed that the number of accounts on the predictive modeling of stresses and optimizing laser scan strategies in multimaterial PBF is low with a (very) limited range of applications. To facilitate future developments in this direction, the key information of the simulation efforts and the state-of-the-art computational models of multimaterial PBF are provided.

This paper aims to explain a celebrity’s deep resonance with consumers by unpacking the individual constituents of a celebrity’s polysemic appeal. While celebrities are traditionally theorised as unidimensional semiotic receptacles of cultural meaning, the authors conceptualise them here instead as human beings/performers with a multi-constitutional, polysemic consumer appeal.

Supporting evidence is drawn from autoethnographic data collected over a total period of 25 months and structured through a hermeneutic analysis.

In rehumanising the celebrity, the study finds that each celebrity offers the individual consumer a unique and very personal parasocial appeal as the performer, the private person behind the public performer, the tangible manifestation of either through products and the social link to other consumers. The stronger these constituents, individually or symbiotically, appeal to the consumer’s personal desires, the more s/he feels emotionally attached to this particular celebrity.

Although using autoethnography means that the breadth of collected data is limited, the depth of insight this approach garners sufficiently unpacks the polysemic appeal of celebrities to consumers.

The findings encourage talent agents, publicists and marketing managers to reconsider underlying assumptions in their talent management and/or celebrity endorsement practices.

While prior research on celebrity appeal has tended to enshrine celebrities in a “dehumanised” structuralist semiosis, which erases the very idea of individualised consumer meanings, this paper reveals the multi-constitutional polysemy of any particular celebrity’s personal appeal as a performer and human being to any particular consumer.

A transient magneto-quasistatic vector potential formulation involving nonlinear material is spatially discretized using the finite element method of first and second polynomial order. By applying a generalized Schur complement the resulting system of differential algebraic equations is reformulated into a system of ordinary differential equations (ODE). The ODE system is integrated in time by using explicit time integration schemes. The purpose of this paper is to investigate explicit time integration for eddy current problems with respect to the performance of the first-order explicit Euler scheme and the Runge-Kutta-Chebyshev (RKC) method of higher order.

The ODE system is integrated in time using the explicit Euler scheme, which is conditionally stable by a maximum time step size. To overcome this limit, an explicit multistage RKC time integration method of higher order is used to enlarge the maximum stable time step size. Both time integration methods are compared regarding the overall computational effort.

The numerical simulations show that a finer spatial discretization forces smaller time step sizes. In comparison to the explicit Euler time integration scheme, the multistage RKC method provides larger stable time step sizes to diminish the overall computation time.

The explicit time integration of the Schur complement vector potential formulation of eddy current problems is accelerated by a multistage RKC method.

The aim of this study was to prove that radio-frequency (RF) energy with 13.56 MHz can be used for heating building structures in a controlled manner exploiting the advantage that homogeneous heating with sufficient penetration depths can be achieved.

Because parallel electrodes on both sides of the heated structure cannot be used in many practical applications, two special electrode designs have been developed by modeling the field distribution and energy absorption and by carrying out test experiments to validate the simulation results.

One solution is based on a two-dimensional surface capacitor providing certain penetration depths and being especially suitable for treating thin structures such as wooden parquet floor. Such an arrangement can be particularly used for pest control even when sensitive surfaces have to be protected. The other solution uses a capacitive coupling between the grounded shielding and an electrode or an equivalent structure (e.g. moist soil) at the other side of the masonry to establish a sufficiently strong electrical field between a “hot” electrode on the side of the shielding and the coupled rear electrode.

Both solutions significantly enhance the application potential of RF heating.