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The Apulian Castel del Monte has a distinct floor plan that is based upon three concentric octagons. This is why the proportions of the floor plan are based upon the Silver Ratio. However, this proporational system requires measurements which have irrational numbers that are very difficult to work with on a construction site. For this reason, the design of the building was converted into a modular system during the early construction planning phase. The modular system operates with whole numbers while preserving the intended design concept. The ratio of 17 to 7 is of fundamental importance here.

Das JuWi-Treffen wurde erstmalig 1999 in Weimar veranstaltet und findet seitdem jährlich im Wechsel an Wasserbauinstituten verschiedener Universitäten statt. Vorherige Treffen wurden unter anderem in Zürich, Dresden, Braunschweig und Graz ausgetragen. Ziel der Treffen ist es, wissenschaftliche MitarbeiterInnen und insbesondere DoktorandInnen aus dem Bereich des Wasserbaus zusammenzuführen und einen fachlichen Austausch in einem informellen Rahmen zu ermöglichen. Die in diesem Tagungsband zusammengestellten Beiträge fassen die Vorträge des diesjährigen Treffens in Form von jeweils vierseitigen "Extended Abstracts" zusammen.

This Article presents a conceptual and methodological account of a small porn bot network, focusing on its embeddedness within Instagram use. The analysis explores the gendered design of bots as platform-native personas, particularly their capacity to perform within the confines of Instagram's increasingly strict sexual content controls. We address three performative trajectories in the bot-exploited 'Instagrammatics' of identity play, social influence, and attention capture. We argue that a bot programmed to operate with sexual content to generate attention relies on the paradoxical blend of pornographic 'imagination' and social media 'authenticity'. For our analysis, we manually identified 30 porn bot accounts spamming in the comment sections of highly visible Instagram posts (those published by @justinbieber). We then collected associated metadata – bot profile names and images, comments and comment likers, followers and followings, bot content, and links in the bot profile bios. By variously situating and combining these data, we discuss how networked automation taps into the sexualized social scripts imitated by 'artificial' and 'authentic' users alike. Our findings point to how porn bots re-enact gender as a programmed set of instructions, adapting to Instagram's vision of acceptable sexuality and revealing its normative order.

"3.Welt"-Perspektiven Dritte-Welt-Perspektiven

Since we are living in a three-dimensional world, an adequate description of our environment for many applications includes the relative position and motion of the different objects in a scene. Nature has satisfied this need for spatial perception by providing most animals with at least two eyes. This stereo vision ability is the basis that allows the brain to calculate qualitative depth information of the observed scene. Another important parameter in the complex human depth perception is our experience and memory. Although it is far more difficult, a human being is even able to recognize depth information without stereo vision. For example, we can qualitatively deduce the 3D scene from most photos, assuming that the photos contain known objects [COR]. The acquisition, storage, processing and comparison of such a huge amount of information requires enormous computational power - with which nature fortunately provides us. Therefore, for a technical implementation, one should resort to other simpler measurement principles. Additionally, the qualitative distance estimates of such knowledge-based passive vision systems can be replaced by accurate range measurements. Imaging 3D measurement with useful distance resolution has mainly been realized so far with triangulation systems, either passive triangulation (stereo vision) or active triangulation (e.g. projected fringe methods). These triangulation systems have to deal with shadowing effects and ambiguity problems (projected fringe), which often restrict the range of application areas. Moreover, stereo vision cannot be used to measure a contrastless scene. This is because the basic principle of stereo vision is the extraction of characteristic contrast-related features within the observed scene and the comparison of their position within the two images. Also, extracting the 3D information from the measured data requires an enormous time-consuming computational effort. High resolution can only be achieved with a relatively large triangulation base and hence large camera systems. A smarter range measurement method is the TOF ( T ime- O f- F light) principle, an optical analogy to a bat´s ultrasonic system rather than human´s stereo vision. So far TOF systems are only available as 1D systems (point measurement), requiring laser scanners to acquire 3D images. Such TOF scanners are expensive, bulky, slow, vibration sensitive and therefore only suited for restricted application fields. In this dissertation an imaging, i.e. non-scanning TOF-camera is introduced, based on an array of demodulation pixels, where each pixel can measure both the background intensity and the individual arrival time of an RF-modulated (20 MHz) scene illumination with an accuracy of a few hundreds of picoseconds (300⋅10 -12 s). The pixel´s working concept is based on the CCD principle ( C harge C oupled D evice), allowing the transportation, storage and accumulation of optically generated charge carriers to defined local sites within the imaging device. This process is extremely fast and essentially loss-free. We call our new, powerful high-functionality pixels demodulation pixels because they extract the target´s distance and reflectivity from the received optical signal. This extracted information is modulated into the active optical signal during the time of propagation of the light (or time of flight) through the observed scene. Each pixel works like an individual high-precision stopwatch, and since its realization is mainly based on CMOS technology this new technique will benefit from the ongoing technology developments in terms of improved time- and hence distance resolution. Thanks to the use of CMOS, all commonly known CMOS APS ( A ctive P ixel S ensor) features ( R egions O f I nterest addressing: ROI, AD conversion, etc.) can be implemented monolithically in the future. The imaging devices have been fabricated in a 2 µm CMOS/CCD process, a slightly modified CMOS process which is available as an inexpensive prototyping service ( M ulti P roject W afer: MPW). This process offers the freedom to implement CCDs with sufficiently good performance for our application, although the performance is inferior to dedicated CCD technologies. We have realized and characterized several different pixel structures and will present these results here. The demodulation pixel with the best fill-factor and demodulation performance has been implemented (1) as a line sensor with 108 pixels and (2) as an image sensor with 64 x 25 pixels. Both devices have been integrated in separate range cameras working with modulated LED illumination and covering a distance range of 7.5 up to 15 meters. For non-cooperative diffusely reflecting targets these cameras achieve centimeter accuracy. With the single exception of the demodulation pixel array itself, only standard electronic and optical components have been used in these range cameras. For a resolution of 5 centimeters, an optical power of 600 fW per pixel is sufficient, assuming an integration time of 50 ms (20 Hz frame rate of 3D images). This low optical power implies that only 0.06 electrons are generated per modulation period (T mod =50 ns at 20 MHz modulation frequency). Furthermore, we present an in-depth analysis of the influences of non-linearities in the electronics, aliasing effects, integration time and modulation functions. Also, an optical power budget and a prediction for the range accuracy is derived as a function of the ratio of active illumination to background illumination. The validity of this equation is confirmed by both computer simulations and experimental measurements with real devices. Thus, we are able to predict the range accuracy for given integration time, optical power, target distance and reflectance. With this work we demonstrate the first successful realization of an all-solid-state 3D TOF range-camera without moving parts that is based on a dedicated customized PhotoASIC. The measured performance is very close to the theoretical limits. We clearly demonstrate that optical 3D-TOF is an excellent, cost-effective tool for all modern vision problems, where the relative position or motion of objects need to be monitored.

Vor 50 Jahren erschien "Understanding Media" von Marshall McLuhan. Das aktuelle "Navigationen"-Heft nimmt in fünf Beiträgen das Jubiläum zum Anlass, dieses Buch systematisch und historisch unter die Lupe zu nehmen. Die Beiträge setzen dazu an, die Situation des Buches zu verstehen, um etwas über seine Medien zu erfahren. Die Dramaturgie der Texte reicht von der handwerklichen Bearbeitung des Buches und seine Weitsicht hinsichtlich der Zukunft der Bücher über das Fernsehen seiner Zeit bis hin zur Rezeption seiner Inhalte in der deutschsprachigen Presse und seinem technikphilosophischen Kontext.