Acquisition, Modeling, and Augmentation of Reflectance for Synthetic Optical Flow Reference Data

This thesis is concerned with the acquisition, modeling, and augmentation of material reflectance to simulate high-fidelity synthetic data for computer vision tasks. The topic is covered in three chapters: I commence with exploring the upper limits of reflectance acquisition. I analyze state-of-the-art BTF reflectance field renderings and show that they can be applied to optical flow performance analysis with closely matching performance to real-world images. Next, I present two methods for fitting efficient BRDF reflectance models to measured BTF data. Both methods combined retain all relevant reflectance information as well as the surface normal details on a pixel level. I further show that the resulting synthesized images are suited for optical flow performance analysis, with a virtually identical performance for all material types. Finally, I present a novel method for augmenting real-world datasets with physically plausible precipitation effects, including ground surface wetting, water droplets on the windshield, and water spray and mists. This is achieved by projecting the realworld image data onto a reconstructed virtual scene, manipulating the scene and the surface reflectance, and performing unbiased light transport simulation of the precipitation effects

Rain rendering for evaluating and improving robustness to bad weather

Rain fills the atmosphere with water particles, which breaks the common assumption that light travels unaltered from the scene to the camera. While it is well-known that rain affects computer vision algorithms, quantifying its impact is difficult. In this context, we present a rain rendering pipeline that enables the systematic evaluation of common computer vision algorithms to controlled amounts of rain. We present three different ways to add synthetic rain to existing images datasets: completely physic-based; completely data-driven; and a combination of both. The physic-based rain augmentation combines a physical particle simulator and accurate rain photometric modeling. We validate our rendering methods with a user study, demonstrating our rain is judged as much as 73% more realistic than the state-of-theart. Using our generated rain-augmented KITTI, Cityscapes, and nuScenes datasets, we conduct a thorough evaluation of object detection, semantic segmentation, and depth estimation algorithms and show that their performance decreases in degraded weather, on the order of 15% for object detection, 60% for semantic segmentation, and 6-fold increase in depth estimation error. Finetuning on our augmented synthetic data results in improvements of 21% on object detection, 37% on semantic segmentation, and 8% on depth estimation.Comment: 19 pages, 19 figures, IJCV 2020 preprint. arXiv admin note: text overlap with arXiv:1908.1033

Surface Engineering for Phase Change Heat Transfer: A Review

Among numerous challenges to meet the rising global energy demand in a sustainable manner, improving phase change heat transfer has been at the forefront of engineering research for decades. The high heat transfer rates associated with phase change heat transfer are essential to energy and industry applications; but phase change is also inherently associated with poor thermodynamic efficiencies at low heat flux, and violent instabilities at high heat flux. Engineers have tried since the 1930's to fabricate solid surfaces that improve phase change heat transfer. The development of micro and nanotechnologies has made feasible the high-resolution control of surface texture and chemistry over length scales ranging from molecular levels to centimeters. This paper reviews the fabrication techniques available for metallic and silicon-based surfaces, considering sintered and polymeric coatings. The influence of such surfaces in multiphase processes of high practical interest, e.g., boiling, condensation, freezing, and the associated physical phenomena are reviewed. The case is made that while engineers are in principle able to manufacture surfaces with optimum nucleation or thermofluid transport characteristics, more theoretical and experimental efforts are needed to guide the design and cost-effective fabrication of surfaces that not only satisfy the existing technological needs, but also catalyze new discoveries

Not just seeing, but also feeling art: mid-air haptic experiences integrated in a multisensory art exhibition

The use of the senses of vision and audition as interactive means has dominated the field of Human-Computer Interaction (HCI) for decades, even though nature has provided us with many more senses for perceiving and interacting with the world around us. That said, it has become attractive for {HCI} researchers and designers to harness touch, taste, and smell in interactive tasks and experience design. In this paper, we present research and design insights gained throughout an interdisciplinary collaboration on a six-week multisensory display – Tate Sensorium – exhibited at the Tate Britain art gallery in London, UK. This is a unique and first time case study on how to design art experiences whilst considering all the senses (i.e., vision, sound, touch, smell, and taste), in particular touch, which we exploited by capitalizing on a novel haptic technology, namely, mid-air haptics. We first describe the overall set up of Tate Sensorium and then move on to describing in detail the design process of the mid-air haptic feedback and its integration with sound for the Full Stop painting by John Latham (1961). This was the first time that mid-air haptic technology was used in a museum context over a prolonged period of time and integrated with sound to enhance the experience of visual art. As part of an interdisciplinary team of curators, sensory designers, sound artists, we selected a total of three variations of the mid-air haptic experience (i.e., haptic patterns), which were alternated at dedicated times throughout the six-week exhibition. We collected questionnaire-based feedback from 2500 visitors and conducted 50 interviews to gain quantitative and qualitative insights on visitors’ experiences and emotional reactions. Whilst the questionnaire results are generally very positive with only a small variation of the visitors’ arousal ratings across the three tactile experiences designed for the Full Stop painting, the interview data shed light on the differences in the visitors’ subjective experiences. Our findings suggest multisensory designers and art curators can ensure a balance between surprising experiences versus the possibility of free exploration for visitors. In addition, participants expressed that experiencing art with the combination of mid-air haptic and sound was immersive and provided an up-lifting experience of touching without touch. We are convinced that the insights gained from this large-scale and real-world field exploration of multisensory experience design exploiting a new and emerging technology provide a solid starting point for the {HCI} community, creative industries, and art curators to think beyond conventional art experiences. Specifically, our work demonstrates how novel mid-air technology can make art more emotionally engaging and stimulating, especially abstract art that is often open to interpretation

Reprocessing interference : an artistic exploration of the visual material generated by interference

Includes bibliographical references (leaves 45-47).My body of work is concerned with the constructed promise of telecommunication - that is, the promise to connect people all over the world via telephone lines, computer networks and, most recently, satellite signals. The development of and access to networked systems has brought about this "utopian promise" (Mitchell 2005: 305), an ideal of instant connectivity that allows a user to be in contact with others through technological devices over vast distances. Connectivity supposedly enables users to develop and sustain relationships on the Internet. However, the question arises whether telecommunication technologies are living up to their promise. My title, Reprocessing Inte/ference: An artistic exploration of the visual material generated by inte/terence, refers to the concepts pertaining to this promise and also to the failure of the promise, focusing on the notions of distance and interference. It further encapsulates my working method, a process of degrading and filtering both my own and found footage

Off the Orbit: Works of Art for Long-Term Space Travellers. Outline of a novel artistic practice

Full version unavailable due to 3rd party copyright restrictions.This research combines the arts with human spaceflight. The aim of the investigation is to identify the aesthetic parameters for display in works of art on extended crewed missions. The study claims that, within the research area of human spaceflight, novel working methods should be developed that can integrate the artist into the scientific process. The extraordinary challenges of extended space exploration not only concern technical and human-bodily aspects, they will also affect the enormous psychological and psychosocial restrictions the spacefarer will face. These limitations are due to the unusual distance and the long timeframes; the future explorers will live confined and isolated within the habitat environment far away from their place of origin. In addition, the consequences of sensory deprivation caused by the high-tech indoor habitat, the emptiness of outer space, the effects of social monotony and limited contact with home will dominate their life in the extreme environment and the emotional state of the future explorer. Many cultural techniques for recreation and stress mitigation are already in use or will be tested in human spaceflight in the near future. However, in this context the implementation of works of art has not been evaluated. The production of works of art for future astronauts represents a new research area. From the artistic perspective, creativity will expand in an unusual manner. Artists will not only have to develop significant metaphors, they will also be confronted with an unknown responsibility, because the confined and isolated astronaut will become the exclusive audience and user of their works. Furthermore, works of art must follow the particular demands of verifiability, safety, and reliability. These specific conditions will give the artistic work a unique meaning which makes the work a part of the life-sustaining system. The outcome will be an experiment that combines both artistic and scientific strategies

Surface engineering for phase change heat transfer: A review

Owing to advances in micro- and nanofabrication methods over the last two decades, the degree of sophistication with which solid surfaces can be engineered today has caused a resurgence of interest in the topic of engineering surfaces for phase change heat transfer. This review aims at bridging the gap between the material sciences and heat transfer communities. It makes the argument that optimum surfaces need to address the specificities of phase change heat transfer in the way that a key matches its lock. This calls for the design and fabrication of adaptive surfaces with multiscale textures and non-uniform wettability. Among numerous challenges to meet the rising global energy demand in a sustainable manner, improving phase change heat transfer has been at the forefront of engineering research for decades. The high heat transfer rates associated with phase change heat transfer are essential to energy and industry applications; but phase change is also inherently associated with poor thermodynamic efficiency at low heat flux, and violent instabilities at high heat flux. Engineers have tried since the 1930s to fabricate solid surfaces that improve phase change heat transfer. The development of micro and nanotechnologies has made feasible the high-resolution control of surface texture and chemistry over length scales ranging from molecular levels to centimeters. This paper reviews the fabrication techniques available for metallic and silicon-based surfaces, considering sintered and polymeric coatings. The influence of such surfaces in multiphase processes of high practical interest, e.g., boiling, condensation, freezing, and the associated physical phenomena are reviewed. The case is made that while engineers are in principle able to manufacture surfaces with optimum nucleation or thermofluid transport characteristics, more theoretical and experimental efforts are needed to guide the design and cost-effective fabrication of surfaces that not only satisfy the existing technological needs, but also catalyze new discoverie

Life Expansion: Toward an Artistic, Design-Based Theory of the Transhuman / Posthuman

The thesis’ study of life expansion proposes a framework for artistic, design-based approaches concerned with prolonging human life and sustaining personal identity. To delineate the topic: life expansion means increasing the length of time a person is alive and diversifying the matter in which a person exists. For human life, the length of time is bounded by a single century and its matter is tied to biology. Life expansion is located in the domain of human enhancement, distinctly linked to technological interfaces with biology. The thesis identifies human-computer interaction and the potential of emerging and speculative technologies as seeding the promulgation of human enhancement that approach life expansion. In doing so, the thesis constructs an inquiry into historical and current attempts to append human physiology and intervene with its mortality. By encountering emerging and speculative technologies for prolonging life and sustaining personal identity as possible media for artistic, design-based approaches to human enhancement, a new axis is sought that identifies the transhuman and posthuman as conceptual paradigms for life expansion. The thesis asks: What are the required conditions that enable artistic, design-based approaches to human enhancement that explicitly pursue extending human life? This question centers on the potential of the study’s proposed enhancement technologies in their relationship to life, death, and the human condition. Notably, the thesis investigates artistic approaches, as distinct from those of the natural sciences, and the borders that need to be mediated between them. The study navigates between the domains of life extension, art and design, technology, and philosophy in forming the framework for a theory of life expansion. The critical approach seeks to uncover invisible borders between these interconnecting forces by bringing to light issues of sustaining life and personal identity, ethical concerns, including morphological freedom and extinction risk. Such issues relate to the thesis’ interest in life expansion and the use emerging and speculative technologies. 4 The study takes on a triad approach in its investigation: qualitative interviews with experts of the emerging and speculative technologies; field studies encountering research centers of such technologies; and an artistic, autopoietic process that explores the heuristics of life expansion. This investigation forms an integrative view of the human use of technology and its melioristic aim. The outcome of the research is a theoretical framework for further research in artistic approaches to life expansion

Artistic research into distraction, agency, and the internet

This practical study is concerned with flows of attention and distraction that are associated with experiences of the internet. Taking the term ‘internet’ to stand for a range of networked social, media-consumption, and data practices carried out on devices such as smartphones, this study sets out to explore how distraction might arise, how it might be conceptualised, and the potential consequences for agency of the conditions of its emergence. The study is led by the production and analysis of artworks, using practical approaches that engage critically with aspects of the experience of the internet. This thesis begins by exploring conceptions of the ‘attention economy’ articulated by Goldhaber (1997), Beller (2006), and Citton (2017), developing an understanding that counters mainstream deterministic positions regarding the impact of digital technologies on the capacity for focused attention. Distraction is considered as an experience that may be sought out by individuals but can be captured and extended by third parties such as social media platforms. The importance of the data generated by habitual or compulsive engagement with internet-enabled devices and services (Zuboff, 2015) is considered against a backdrop of quantification and managerialism that extends beyond experiences of the internet. The study reviews existing artworks made in response to these concerns, focusing on expressions of the ‘attention economy’ prevalent in ‘postinternet’ art. Works by Vierkant (2010), Roth (2015) and others that interrogate infrastructure, data-gathering, or networked methods of distribution are identified as relevant, and a position is developed from which the consequences of metricised display platforms for an artistic ‘attention economy’ can be explored. Prototype artworks made during the study are appraised using an artistic research methodology that foregrounds the role of the researcher as both producer and reader of the artwork. Works that actively create distraction, that gather and visualise data, and that emphasise calm self-interrogation, are discussed and evaluated. The practical aspects of the research contribute to knowledge by extending understanding of the spatial, infrastructural, and algorithmic dimensions of the relationship between distraction and agency