Zoekresultaten

Toward live domain-specific languages

Live programming is a style of development characterized by incremental change and immediate feedback. Instead of long edit-compile cycles, developers modify a running program by changing its source code, receiving immediate feedback as it instantly adapts in response. In this paper, we propose an approach to bridge the gap between running programs and textual domain-specific languages (DSLs). The first step of our approach consists of applying a novel model differencing algorithm, tmdiff, to the textual DSL code. By leveraging ordinary text differencing and origin tracking, tmdiff produces deltas defined in terms of the metamodel of a language. In the second step of our approach, the model deltas are applied at run time to update a running system, without having to restart it. Since the model deltas are derived from the static source code of the program, they are unaware of any run-time state maintained during model execution. We therefore propose a generic, dynamic patch architecture, rmpatch, which can be customized to cater for domain-specific state migration. We illustrate rmpatch in a case study of a live programming environment for a simple DSL implemented in Rascal for simultaneously defining and executing state machines.

The riddle of the real city

Does our knowledge about city and urban planning have solid ground? Can historical research promote creative thinking? How can we theorise about urban design and architecture in our age of the media? These questions have guided the creation of this multi-layered, richly documented and illustrated triptych, in which the Dutch architectural theorist Wim Nijenhuis pursues a creative goal: to stimulate new ways of thinking in architectural culture.Each part of the triptych treats distinctive issues with a particular style of writing:I – a treatise on urban history. Using the archaeological-genealogical toolkit Nijenhuis reveals the difference between urbanistic discourse in the modern and the classical age; the first staging the street and public space, the latter adhering to representation and mathematical order. In great detail he shows how modern urbanism did not emerge from idealistic motives and technical urgencies, but from an accidental mix of medical, engineering and aesthetical parlances, and how classical thinking on the city dissociated from Renaissance by an intertwining of military science, political science, anthropology and ethics.II – a bundle of essays about the condition of the city in our media age. In strikingly composed texts the author prophesies how rapid traffic and transmission speed of media will distort the perception of our real cities. This gradual event will profoundly influence the cultural role of architecture.III – a set of meditations about epistemological problems. Questioning the practice of critical writing, Nijenhuis proposes change of subjectivity (and thereby worldview), ethical indifference, parody, curative mythomania and hypermodern dilettantism.The book is composed as a cloud essay that serves to enrich the reader’s theoretical understanding of urban interventions. Dialoguing with philosophers like Bataille, Deleuze, Foucault, Klossowski, Sloterdijk and Virilio, Nijenhuis covers multiple disciplines such as urbanism, architecture, history, media science, philosophy and art. Stretching urbanistic thinking beyond its limits he carries the reader along into the miraculous world of the street, the engineer, the norm, the form, order, fortresses, discipline, army camps, city frontiers, the Temple of Salomon, the quest for beauty, the ‘impressiveness’ of images, speed, the tragedy of the omnipolis, solidification of time, and the liquidising potency of apocalypticism and Taoist non-action.The Riddle of the Real City testifies to four experimental exercises: transitory subjectivism to reveal hidden dimensions of the person, transhistorical verticality to communicate with singular events from the past, theory as toolkit and pursuing a personal path in reading and investigation.

Valuing the client or the property?

This thesis provides an examination of judgement autonomy of Dutch commercial real estate valuers in relation to client orientation. The valuation of commercial real estate such as offices or retail properties requires in-depth analysis due to its uniqueness by location, building type and usage details. Essentially, a register-valuer is qualified and instructed to assess a property value to one’s best cognitive effort and inform others of this outcome by means of a valuation report. In the Netherlands, concerns over independence risks and client-related judgement risks of valuers have been raised by regulative authorities as the Dutch Central Bank (DNB) and the Dutch Authority for the Financial Markets (AFM). A significant part of these concerns followed the 2008 financial crisis, which appeared to be at least partially driven by unreliable and incomparable valuations of Dutch commercial real estate (AFM, 2014; DNB, 2012; 2015). Among other things, these concerns led to the instigation of the Nederlands Register Vastgoed Taxateurs (NRVT) in 2015. NRVT is a new Dutch central register of valuation practitioners set up in order to improve self-regulation, quality control and compliance of valuation practitioners. Currently, the chamber for commercial real estate valuation holds about 2,000 commercial valuation registrations (NRVT, 2020). The introduction of NRVT, and other measures taken, reflect an instrumental view towards enhancing professionalism of Dutch valuers. This view is based on a systematic orientation to professional conduct in which good practice is primarily objectively determined (Van Ewijk, 2019). However, Wassink and Bakker (2016) point out that individuals make personal choices in order to deal with work complexity. Insight into and reflection on individual choices is part of what is referred to as normative aspects of professionalisation: what norms prevail in individual judgement and decision-making and why (Van Ewijk, 2019). In this regard, insight into judgement reasoning of valuation practitioners may contribute to normative levels of professional development of valuers. The need for such is expressed through community concerns over how individual judgement autonomy may become subdued due to instrumental-driven developments taking place in the sector. The combination of authoritative concerns over professional quality in the Netherlands and lack of (scientific) insight on how client influence affects judgement in valuation practice poses a problem: How may practitioners address client-related judgement bias risks and improve valuation accuracy from this viewpoint, if little is known on how such risks may occur in daily practice? The seemingly scarce scientific insights available in this regard in the Netherlands may also prevent educational programs to adequately address valuer independence and objectivity risks in relevant training programs. In order to address this knowledge gap, the present PhD research examines the following research problem: 169 Summary “How does client orientation affect professional judgement autonomy of commercial real estate valuers in the Netherlands?” The term ‘client orientation’ should be broadly interpreted and may refer to valuers’ perception, understanding and meaning given to alleged, actual or anticipated client-related aspects. Information on such client aspects is not required for the performance of valuation instructions. It should also be noted that this research examines the context of how client orientation may affect valuer judgement reasoning patterns during work practice, yet not its effect in terms of decision on final value opinion.

Real-time ray tracing through the eyes of a game developer.

The Brigade Renderer: A path tracer for real-time games

We present the Brigade renderer: an efficient system that uses the path tracing algorithm to produce images for real-time games. We describe the architecture of the Brigade renderer, and provide implementation details. We describe two games that have been created using Brigade.

Neural Bidirectional Texture Function Compression and Rendering

The recent success of Machine Learning encouraged research using artificial neural networks (NNs) in computer graphics. A good example is the bidirectional texture function (BTF), a data-driven representation of surface materials that can encapsulate complex behaviors that would otherwise be too expensive to calculate for real-time applications, such as self-shadowing and interreflections. We propose two changes to the state-of-the-art using neural networks for BTFs, specifically NeuMIP. These changes, suggested by recent work in neural scene representation and rendering, aim to improve baseline quality, memory footprint, and performance. We conduct an ablation study to evaluate the impact of each change. We test both synthetic and real data, and provide a working implementation within the Mitsuba 2 rendering framework. Our results show that our method outperforms the baseline in all these metrics and that neural BTF is part of the broader field of neural scene representation. Project website: https://traverse-research.github.io/NeuBTF/.