Open Access

Seit der Saison 2014 veröffentlichen wir alle 4 Monate unseren Newsletter "Werkstattgeflüster", der unseren Unterstützern, Förderern und Freunden gleichermaßen einen Einblick in unser Projekt geben soll. Über die Saison verteilt möchten wir so verstärkt über die Events und unsere Zusammenarbeit mit unseren Sponsoren berichten und unseren Mitgliedern die Chance geben, Ihre Arbeit im Team vorzustellen.

Technikjournalismus ist eine noch recht junge Sparte im Fachjournalismus und umfasst die Berichterstattung über Themen aus den Gebieten, Bauen und Wohnen, Energie und Umwelt, Verkehr und Transport, Gewerbe und industrielle Produktion, Handel und Dienstleistungen sowie Information und Kommunikation.Dieser Band gibt zunächst einen Überblick über das Berufsbild des Technikjournalisten, den Gegenstand seiner Berichterstattung, die Recherche, typische Darstellungsformen und sprachliche Besonderheiten. Anschließend wird der Technikjournalismus in den verschiedenen Printmedien sowie im Hörfunk, Fernsehen und Internet vorgestellt; erfahrene Fachjournalisten wie namhafte Wissenschaftler beschreiben die medienspezifischen Besonderheiten, erläutern Spezifika von Recherche und Darstellung und vermitteln Handwerk und Orientierung. Auch das Verhältnis zur Wissenschaft und zu den Public Relations wird untersucht. Ausführungen über rechtliche und ethische Rahmenbedingungen runden das Buch ab.

Design ist allgegenwärtig - es durchtränkt gleichsam das Leben, oftmals unbewusst, doch immer durchscheinend und folgenhaft. Es ist Bestandteil des Habitus und unverzichtbarer Teil einer jeden Identität. Selbst im bewussten Verzicht auf Design kommt eine spezifische Designästhetik zum Ausdruck, die anders sein möchte. Doch welche Normierungen greifen hier und dienen als Orientierung für Absetzbewegungen? Dies zeigt sich vor allem in der Prägung durch massenmediale Diskurse. Die Beiträge des Bandes entwickeln zu diesem zentralen Dispositiv einen theoretischen wie praktischen Rahmen und reflektieren Indikatoren für entsprechende Leistungen.

Einer Moderne in der Tradition der Aufklärung, zweckrational gestimmt und zum Pragmatischen geneigt, muß Repräsentatives verdächtig vorkommen. Die Verpflichtung zu einer Wahrheit, die um so lauterer erscheint, je schmuck- und glanzloser sie daherkommt, beargwöhnt das Repräsentative bestenfalls als Schnickschnack, in weniger günstigen Stunden als Einschüchterung oder Manipulation.

The paper presents the design of a baseband pi/4-DQPSK complex wavelet packet modulation CWPM transceiver and the results of its FPGA implementation. The design uses 8-point Discrete Wavelet Packet Transform (DWPT) and its inverse as core processing modules. All modules have been designed using VHDL programming language together with the Altera software tools Quartus II 9.1 and ModelSim 6.5b. The transceiver was implemented on a Cyclone III board.

The requirements of an efficient communication scheme for wireless sensing applications have been investigated. The noncoherent direct chaotic communication scheme called chaos on-off keying (COOK) has presented itself as a promising candidate. This paper proposes a modified version of the COOK scheme to improve its performance in noisy and fading environments. The proposed scheme is designed to increase the signal space of the decision variable by using the concept of differential correlation keeping implementation requirements simple. The results show that the proposed modified version of the COOK scheme achieves less bit-error probability in noisy and fading channels at moderate signal-to-noise ratio values and almost constant detection threshold as compared with the original version.

The main requirements of efficient steganographic systems are transparency, robustness and security. In this work, the proposed system is designed to achieve these requirements, as follows: to increase the transparency and robustness, the proposed system uses the transform domain technique, in this case the wavelet domain technique to embed the color secret image into the color cover image. To achieve high security, chaotic systems are used to accomplish the following two purposes: firstly to scramble the secret color image before hiding it into the color cover image, secondly to randomly select the embedding positions in the cover image. Three chaotic systems with many combinations are used for the scrambling and the embedding process. Experimental results including Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), Correlation, Signal to Noise Ratio (SNR) and embedding capacity demonstrate that the proposed system has good performance as compared with other existing methods without attack and under different types of attacks such as filtering and noise attacks. Simulation results show that the combination of chaotic systems providing the best performance include the use of Logistic and Hénon maps for the embedding process and Arnold's cat map for the encryption process. The MSE, PSNR, correlation, SNR and embedding capacity obtained in this case reach up to 0.0010, 78.1dB, 0.9999, 67.2dB and 0.39% respectively when the secret image is Airplane with 32×32 pixels and the cover image is Girl with 512×512 pixels. For the extracted secret image, the chaotic system set that provides the best performance includes the use of Arnold's cat map for the encryption process. The MSE, PSNR, correlation and SNR obtained in this case reach up to 0.0846, 58.9dB, 1 and 56.1dB respectively. As compared with other methods, the proposed method achieves gains without any attack of 8.2dB for the stego image and 32.4dB for the extracted secret image in PSNR when the secret image is Airplane with 256×256 pixels and the cover image is Girl with 512×512 pixels.

This paper describes a project carried out at the Bonn-Rhein-Sieg University to teach low-power digital design structures in a laboratory. Low-power design has become one of the most essential constraints in digital systems, especially in portable devices. For this purpose, low-power design is a topic addressed in electrical and computer curricula, but it also requires applications in a laboratory. Therefore, this project focuses on preparing students for current trends in low-power design by examining realistic applications of its basic theories and principles, either hands-on or remotely. The laboratory's experiments use a field programmable gate array (FPGA) as a design platform for implementing the students' digital designs. This contribution reports on our first experiences in teaching low-power design in the lab. This paper focuses on the educational impact on students regarding the following: (1) overall objectives in the laboratory, (2) experimental exercises with low-power techniques, and (3) using educational FPGA boards and the EduPow board. The EduPow board is a developed hands-on board at the Bonn-Rhein-Sieg University that is relatively specific on using various signal image-processing applications to directly observe the power dissipation of a student's digital algorithm. Our assessment of the low-power design lab shows that the requirements and objectives of this project are fairly well satisfied. In addition, students' feedback indicates that using the EduPow board is more attractive and motivational in their work.

This paper investigates how learning objectives can be complemented by employing a remote system to improve teaching low-power digital circuits design. The low-power design laboratory system that has been developed at the Bonn-Rhine-Sieg University of Applied Sciences is composed of two laboratory types: the on-site (hands-on) and the remote laboratories to teach low-power techniques with laboratory exercises. This laboratory system enables online experiments that can be performed using physical instruments and obtaining real data. Digital circuit designers can observe the most influential factors in power dissipation during laboratory exercises in the on-site system and then use the remote laboratory to supplement investigating other factors. This contribution describes teaching activities performed during the Summer Semester 2015 using only the on-site system, and during the Summer Semester 2016 using the on-site and the remote systems. The assessment studies the achieved learning objectives, evaluates the laboratory reports with and without the support of the remote system, and analyses the students' use of the remote system. The assessment and the students' opinions provide positive feedback on this approach and verify that the remote laboratory system is a successful and effective complementary learning tool for remotely reusing the on-site laboratory and achieving additional learning objectives that cover most conceptual theories in low-power digital circuits design.

The need for innovation around the control functions of inverters is great. PV inverters were initially expected to be passive followers of the grid and to disconnect as soon as abnormal conditions happened. Since future power systems will be dominated by generation and storage resources interfaced through inverters these converters must move from following to forming and sustaining the grid. As “digital natives” PV inverters can also play an important role in the digitalisation of distribution networks. In this short review we identified a large potential to make the PV inverter the smart local hub in a distributed energy system. At the micro level, costs and coordination can be improved with bidirectional inverters between the AC grid and PV production, stationary storage, car chargers and DC loads. At the macro level the distributed nature of PV generation means that the same devices will support both to the local distribution network and to the global stability of the grid. Much success has been obtained in the former. The later remains a challenge, in particular in terms of scaling. Yet there is some urgency in researching and demonstrating such solutions. And while digitalisation offers promise in all control aspects it also raises significant cybersecurity concerns.

The paper presents the topological reduction method applied to gas transport networks, using contraction of series, parallel and tree-like subgraphs. The contraction operations are implemented for pipe elements, described by quadratic friction law. This allows significant reduction of the graphs and acceleration of solution procedure for stationary network problems. The algorithm has been tested on several realistic network examples. The possible extensions of the method to different friction laws and other elements are discussed.