Metal Forming of Vibration‐Damping Composite Sheets

Composite materials with vibrations damping qualities can be made of two steel sheets enclosing a viscoelastic plasticcorelayer. These sandwich sheets often need to be formed. Material parameters are determined to describe the forming process. Based on these parameters, pilot studies are carried out in order to develop recommendations for forming this class of material.     

A fully automated calibration method for an optical see-through head-mounted operating microscope with variable zoom and focus

Ever since the development of the first applications in image-guided therapy (IGT), the use of head-mounted displays (HMDs) was considered an important extension of existing IGT technologies. Several approaches to utilizing HMDs and modified medical devices for augmented reality (AR) visualization were implemented. These approaches include video-see through systems, semitransparent mirrors, modified endoscopes, and modified operating microscopes. Common to all these devices is the fact that a precise calibration between the display and three-dimensional coordinates in the patient's frame of reference is compulsory. In optical see-through devices based on complex optical systems such as operating microscopes or operating binoculars-as in the case of the system presented in this paper-this procedure can become increasingly difficult since precise camera calibration for every focus and zoom position is required. We present a method for fully automatic calibration of the operating binocular Varioscope M5 AR for the full range of zoom and focus settings available. Our method uses a special calibration pattern, a linear guide driven by a stepping motor, and special calibration software. The overlay error in the calibration plane was found to be 0.14-0.91 mm, which is less than 1% of the field of view. Using the motorized calibration rig as presented in the paper, we were also able to assess the dynamic latency when viewing augmentation graphics on a mobile target; spatial displacement due to latency was found to be in the range of 1.1-2.8 mm maximum, the disparity between the true object and its computed overlay represented latency of 0.1 s. We conclude that the automatic calibration method presented in this paper is sufficient in terms of accuracy and time requirements for standard uses of optical see-through systems in a clinical environment.     

UNICORE 6 — Recent and Future Advancements

UNICORE is a European Grid Technology with more than 10 years of history. Originating from the Supercomputing domain, the latest version UNICORE 6 has turned into a general-purpose Grid technology that follows established standards and offers a rich set of features to its users. The paper starts with an architectural insight into UNICORE 6, highlighting the workflow features, standards and the different clients. Next, the current state of advancement is presented by describing recent developments. The paper closes with an outlook on future planned developments.     

Interdigitated back‐contact heterojunction solar cell concept for liquid phase crystallized thin‐film silicon on glass

We present an interdigitated back‐contact silicon heterojunction system designed for liquid‐phase crystallized thin‐film (~10 µm) silicon on glass. The preparation of the interdigitated emitter (a‐Si:H(p)) and absorber (a‐Si:H(n)) contact layers relies on the etch selectivity of doped amorphous silicon layers in alkaline solutions. The etch rates of a‐Si:H(n) and a‐Si:H(p) in 0.6% NaOH were determined and interdigitated back‐contact silicon heterojunction solar cells with two different metallizations, namely Al and ITO/Ag electrodes, were evaluated regarding electrical and optical properties. An additional random pyramid texture on the back side provides short‐circuit current density (j_SC) of up to 30.3 mA/cm² using the ITO/Ag metallization. The maximum efficiency of 10.5% is mainly limited by a low of fill factor of 57%. However, the high j_SC, as well as V_OC values of 633 mV and pseudo‐fill factors of 77%, underline the high potential of this approach. Copyright © 2015 John Wiley & Sons, Ltd.     

Modeling Feedback Bridging Faults with Non-Zero Resistance

We study the behavior of feedback bridging faults with non-zero bridge resistance in both combinational and sequential circuits. We demonstrate that a test vector may detect the fault, not detect the fault or lead to oscillation, depending on bridge resistance. Moreover, the resistance intervals in which a particular behavior is observed are not necessarily contiguous. We demonstrate non-trivial behavior for situations in which a detection seems impossible, namely disabled loops going through a gate with controlling values on its side inputs.We outline the multiple strengths problem which arises due to the fact that a critical bridge resistance depends on the strengths of the signals driving the bridge, which in turn are functions of the number of the on-transistors, these again depending on the bridge resistance, making such a fault very hard to resolve. For sequential circuits, we describe additional difficulties caused by the need to account for implications on bridge behavior, which have originated in the previous time frames. We conclude that the complexity of resistive feedback bridging fault simulation accurate enough to resolve such situations will probably be prohibitively high and propose possible simplifying assumptions. We present simulation results for ISCAS benchmarks using these assumptions with and without taking oscillation into account.This revised version was published online in March 2005 with corrections to the cover date.     

Mirror or Molder? A Study of Media Coverage,Stock Prices,and Trading Volumes in Germany

This article investigates the short‐term relationship between media coverage, stock prices, and trading volumes of eight listed German companies. A content analysis of news reports about the selected companies and a secondary analysis of the daily changes in closing prices and the trading volumes of these companies were combined in a time‐series design. After ARIMA‐modeling each of them, the results suggest that media coverage rather reflects than shapes the development at stock exchanges from a short‐term perspective (2 months). There were almost no hints for a widespread media effect, that is, an impact on so many investors that it will result in a measurable change in stock prices or trading volumes. Finally, theoretical and methodological consequences for exploring widespread media effects are discussed.     

End of life management of industrial robots

End of life management (EOL) is currently a hot topic in the electronics industry. Currently, mostly IT equipment and goods of consumer electronics are considered. In the nearest future automation equipment has also to be taken into account. There are three possibilities depending on the age and kind of the device: resell–reuse–recycle, called the “3Rs”. For recycling fully or semi-automated disassembly will gain in importance in the nearest future also for robots. Producers of robots have to take into account EoL because of regulations and laws as well as according to ethical codes contributing to protection of the environment. Based on previous works a real example will be presented and discussed.