1,538 research outputs found
Strokes2Surface: Recovering Curve Networks From 4D Architectural Design Sketches
We present Strokes2Surface, an offline geometry reconstruction pipeline that
recovers well-connected curve networks from imprecise 4D sketches to bridge
concept design and digital modeling stages in architectural design. The input
to our pipeline consists of 3D strokes' polyline vertices and their timestamps
as the 4th dimension, along with additional metadata recorded throughout
sketching. Inspired by architectural sketching practices, our pipeline combines
a classifier and two clustering models to achieve its goal. First, with a set
of extracted hand-engineered features from the sketch, the classifier
recognizes the type of individual strokes between those depicting boundaries
(Shape strokes) and those depicting enclosed areas (Scribble strokes). Next,
the two clustering models parse strokes of each type into distinct groups, each
representing an individual edge or face of the intended architectural object.
Curve networks are then formed through topology recovery of consolidated Shape
clusters and surfaced using Scribble clusters guiding the cycle discovery. Our
evaluation is threefold: We confirm the usability of the Strokes2Surface
pipeline in architectural design use cases via a user study, we validate our
choice of features via statistical analysis and ablation studies on our
collected dataset, and we compare our outputs against a range of
reconstructions computed using alternative methods.Comment: 15 pages, 14 figure
Urban robotic experimentation: San Francisco, Tokyo and Dubai
Advances in robotics, artificial intelligence and automation have the potential to transform cities and urban social life. However, robotic restructuring of the city is complicated and contested. Technology is still evolving, robotic infrastructure is expensive and there are technical, trust and safety challenges in bringing robots into dynamic urban environments alongside humans. This article examines the nascent field of ‘urban robotics’ in three emblematic yet diverse national-urban contexts that are leading centres for urban robotic experimentation. Focusing on the experimental application of autonomous social robots, the article explores: (i) the rationale for urban robotic experiments and the interests involved, and (ii) the challenges and outcomes of creating meaningful urban spaces for robotic experimentation. The article makes a distinctive contribution to urban research by illuminating a potentially far-reaching but under-researched area of urban policy. It provides a conceptual framework for mapping and understanding the highly contingent, spatially uneven and socially selective processes of robotic urban experimentation
Semantic Shift to Pragmatic Meaning in Shared Decision Making: Situation Theory Perspective
The way humans establish communication depends on the generation and conveyance of meaning. Linguistically, meaning in information is dependent on the meaning that is ascribed to signifiers in the context of the communication. These signifiers can include items such as words, phrases, signs, and symbols. Conveyance of meaning may, however, imprecise and prone to error. The meaning of information in communication may arise from a change in the context in which a signifier is placed (intrinsic), or a change in the paradigm with which the signifier and context are perceived (extrinsic). In simple situations, where paradigms are reconcilable, semantic shift is solely intrinsic. In complex situations, where differing paradigms will generally lead to irreconcilable perspectives (paradoxes and dualities); the semantic shift will be both intrinsic and extrinsic. Decisions are based on an individual\u27s (or individuals\u27 shared) understanding and understanding is in turn contingent on perspective. Decision making will, therefore, be affected by discrepancies in meaning. It is critical to understand the nature of the discrepancies where shared awareness is necessary to enable group decisions. The theoretical construct presented recognizes that (1) a semantic shift may be required where multiple perspectives based on different paradigms come into play and (2) a semantic shift may introduce error, inefficiency, noise or redundancy. Therefore, individual limits can be recognized via shared awareness, which can be studied with situation theory. © 2015 WIT Press
Spin excitations in the nematic phase and the metallic stripe spin-density wave phase of iron pnictides
We present a general study of the magnetic excitations within a weak-coupling
five-orbital model relevant to itinerant iron pnictides. As a function of
enhanced electronic correlations, the spin excitations in the symmetry broken
spin-density wave phase evolve from broad low-energy modes in the limit of weak
interactions to sharply dispersing spin wave prevailing to higher energies at
larger interaction strengths. We show how the resulting spin response at high
energies depends qualitatively on the magnitude of the interactions. We also
calculate the magnetic excitations in the nematic phase by including an orbital
splitting, and find a pronounced C_2 symmetric excitation spectrum right above
the transition to long-range magnetic order. Finally, we discuss the C_2 versus
C_4 symmetry of the spin excitations as a function of energy for both the
nematic and the spin-density wave phase.Comment: 10 pages, 10 figure
Mass Drug Administration and beyond: how can we strengthen health systems to deliver complex interventions to eliminate neglected tropical diseases?
Achieving the 2020 goals for Neglected Tropical Diseases (NTDs) requires scale-up of Mass Drug Administration (MDA) which will require long-term commitment of national and global financing partners, strengthening national capacity and, at the community level, systems to monitor and evaluate activities and impact. For some settings and diseases, MDA is not appropriate and alternative interventions are required. Operational research is necessary to identify how existing MDA networks can deliver this more complex range of interventions equitably. The final stages of the different global programmes to eliminate NTDs require eliminating foci of transmission which are likely to persist in complex and remote rural settings. Operational research is required to identify how current tools and practices might be adapted to locate and eliminate these hard-to-reach foci. Chronic disabilities caused by NTDs will persist after transmission of pathogens ceases. Development and delivery of sustainable services to reduce the NTD-related disability is an urgent public health priority. LSTM and its partners are world leaders in developing and delivering interventions to control vector-borne NTDs and malaria, particularly in hard-to-reach settings in Africa. Our experience, partnerships and research capacity allows us to serve as a hub for developing, supporting, monitoring and evaluating global programmes to eliminate NTDs
BIM in teaching — lessons learned from exploratory study
Building Information Technology bears promise to bring
integration into fragmented AEC industry, as well as large
potentials for optimization and management of building performance
along life cycle. However, the adoption in Central
Europe is much slower than in the USA or Scandinavia; the
designers and planners are sceptical about BIM benefits. In
order to build up capabilities and thus support BIM adoption
in the practice, BIM skills have be built up already in university
teaching. This endeavour is the central aim of the BIM_sustain
project accomplished at the Vienna University of Technology.
In winter term 2012/13 and winter term 2013/14 we accomplished
interdisciplinary BIM-supported design labs with
student participants from architecture, civil engineering and
building science. The teams used different modelling and simulation
software constellations for building design and analysis.
The software-constellations were evaluated in terms of BIMinteroperability,
and the design process was documented by
means of time and activity assessment, surveys on team performance,
process satisfaction and technology acceptance and
focus group interviews. In this paper we will present the results
of the evaluation of both courses and analyse the differences
resulting from the different course design in the two consequent
terms. The first course was dominated by the issue of
interfaces, whereas the second course, where better functioning
software combinations in terms of data transfer were used,
was dominated by the issues related to the collaboration and
teamwork. Our results are not only informative for the configuration
of interdisciplinary BIM-supported university teaching,
but can be derived for the practice as well, especially in the
areas of project management, software usage, modelling conventions
or incentive systems
Single-strand DNA Binding by the Helix-Hairpin-Helix Domain of XPF Contributes to Substrate Specificity of ERCC1-XPF
The nucleotide excision repair protein complex ERCC1-XPF is required for incision of DNA upstream of DNA damage. Functional studies have provided insights into the binding of ERCC1-XPF to various DNA substrates. However, because no structure for the ERCC1-XPF-DNA complex has been determined, the mechanism of substrate recognition remains elusive. Here we biochemically characterize the substrate preferences of the helix-hairpin-helix (HhH) domains of XPF and ERCC-XPF and show that the binding to single-stranded DNA (ssDNA)/dsDNA junctions is dependent on joint binding to the DNA binding domain of ERCC1 and XPF. We reveal that the homodimeric XPF is able to bind various ssDNA sequences but with a clear preference for guanine-containing substrates. NMR titration experiments and in vitro DNA binding assays also show that, within the heterodimeric ERCC1-XPF complex, XPF specifically recognizes ssDNA. On the other hand, the HhH domain of ERCC1 preferentially binds dsDNA through the hairpin region. The two separate non-overlapping DNA binding domains in the ERCC1-XPF heterodimer jointly bind to an ssDNA/dsDNA substrate and, thereby, at least partially dictate the incision position during damage removal. Based on structural models, NMR titrations, DNA-binding studies, site-directed mutagenesis, charge distribution, and sequence conservation, we propose that the HhH domain of ERCC1 binds to dsDNA upstream of the damage, and XPF binds to the non-damaged strand within a repair bubble
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