J Jakob Beetz

Waveguide superconducting single-photon detectors for integrated quantum photonic circuits

The monolithic integration of single-photon sources, passive optical circuits, and single-photon detectors enables complex and scalable quantum photonic integrated circuits, for application in linear-optics quantum computing and quantum communications. Here, we demonstrate a key component of such a circuit, a waveguide single-photon detector. Our detectors, based on superconducting nanowires on GaAs ridge waveguides, provide high efficiency (∼20%) at telecom wavelengths, high timing accuracy (∼60 ps), and response time in the ns range and are fully compatible with the integration of single-photon sources, passive networks, and modulators.

Ifcowl: A case of transforming express schemas into ontologies

Abstract Ontologies have been successfully applied as a semantic enabler of communication between both users and applications in fragmented, heterogeneous multinational business environments. In this paper we discuss the underlying principles, their current implementation status, and most importantly, their applicability to problems in the building information modeling domain. We introduce the development of an ontology for the building and construction sector based on the industry foundation classes. We discuss several approaches of lifting modeling information that is based on the express family of languages for data modeling onto a logically rigid and semantically enhanced ontological level encoded in the W3C Ontology Web Language. We exemplify the added value of such formal notation of building models by providing several examples where generic query and reasoning algorithms can be applied to problems that otherwise have to be manually hard-wired into applications for processing building information. Furthermore, we show how the underlying resource description framework and the set of technologies evolving around it can be tailored to the need of distributed collaborative work in the building and construction industry.

BIMQL - An open query language for building information models

In this paper we present the on-going development of a framework for a domain specific, open query language for building information models. The proposed query language is intended for selecting, updating and deleting of data stored in Industry Foundation Classes models. Even though some partial solutions already have been suggested, none of them are open source, domain specific, platform independent and implemented at the same time. This paper provides an overview of existing approaches, conceptual sketches of the language in development and documents the current state of implementation as a prototype plugin developed for the open source model server platform bimserver.org. We report on the execution of example test-cases to show the general feasibility of the approach chosen.

Exchange of Parametric Bridge Models Using a Neutral Data Format

Parametric modeling is a well-established methodology in the field of mechanical engineering. It allows for the creation of flexible geometric models using parameters for dimensions and makes it possible to define numeric relationships between these parameters by means of mathematical formulas and define geometric-topological constraints between geometric entities. The result is a flexible geometric model that can be steered through the manipulation of its primary parameters. In contrast to explicit geometric models with fixed dimensions, a parametric model can capture the design intent and represent domain knowledge. The use of parametric modeling techniques is particularly beneficial for designing bridges. This is because the geometric design of bridges is mainly determined by external constraints resulting from the size and the layout of both the overlying and the undercrossing carriageway. This reduces the effort required for reworking when changes are made, while simultaneously providing a high degree of reusability for the model in other, similar projects, resulting in significantly increased efficiency in the bridge design process. Because of the strong fragmentation of the architecture, engineering, and construction (AEC) industry, the data exchange between the different participants in a construction project is of crucial importance. The use of neutral, open data formats has proved to be the most suitable approach to realize this data exchange. However, currently existing neutral data formats do not allow for an exchange of parametric geometry. To overcome these technical limitations, this paper introduces an extension to the IFC-Bridge format, thus providing a means of interchanging parametric bridge models. This article describes in detail the necessary entities introduced to define parameters and capture dimensional and geometric constraints. The suitability of the developed extensions is proved by presenting the successful transfer of parametric bridge models between two parametric design systems as well as from a design system to a structural analysis system.

Implementation of a National 3D Standard : case of the Netherlands

This paper describes the motivation and problem statements as well as the ongoing investigations regarding the follow-up activities of the 3D Pilot NL. This pilot is a large collaboration in the Netherlands aiming at pushing 3D developments in the Netherlands. The first phase resulted in a national 3D standard, modeled as CityGML Application Domain Extension. Some insights obtained during this phase are sufficiently mature to be anchored in practice such as maintaining and further developing the 3D standard by Geon ovum and the provision of a countrywide 3D midscale base dataset which is currently under study at the Kadaster. Other results need further attention in a collaborative setting, specifically how the new 3D standard works in practice. This is currently being further explored in a second phase of the 3D Pilot in which over 100 organizations are participating. The goal of the follow-up pilot is more focused than the first pilot and aims at writing best practice documents by joint effort of the 3D Pilot community. The best practice documents are based on tools and techniques that are being developed for supporting the implementation of the 3D standard. Specific attention is being paid how to align City GML to the standard in the BIM (Building information Model) domain (IFC). Initial findings and work in progress are presented.

The role of smart home in smart real estate

Purpose – The purpose of this paper is to review an emerging type of dwelling, indicated as Smart Home, with a focus on future user lifestyles and needs. Trends toward sustainability and technological changes dramatically alter the concepts of Smart Home. Consequently, real estate decisions are going to be affected by the Smart Home development. Inspired by research in the field of user centered design and future lifestyles, the authors redefine the housing design to increase the acceptance of Smart Homes in the society.Design/methodology/approach – Upcoming trends and developments in housing technologies and concepts are reviewed and analyzed. A multidimensional definition of a Smart Home is suggested which allows a better understanding of the new elements and spaces of this future home. A new concept of a home environment is presented in which virtual space and ambient intelligent space is integrated within the physical space. Furthermore, possible changes in lifestyles enabled by new technological deve...

Establishing and implementing a national 3D standard in The Netherlands: Entwicklung und Implementierung eines nationalen 3D Standards in den Niederlanden

This paper describes the 3D developments achieved within the 3D Pilot NL. The first phase of this pilot (January 2010 June 2011) resulted in a national 3D standard, modeled as CityGML application domain extension (ADE). This standard is briefly explained in this paper. To implement this standard as a nationwide 3D dataset, further research was needed. The second phase of the 3D Pilot finished in December 2012 developed tools, techniques and guidelines to support the implementation of the 3D standard. These are: 1) implementation specifications for the national CityGML ADE to be used in tendering documents, 2) example data compliant to the 3D standard, 3) 3D validator, 4) guidelines to update 3D datasets, and 5) 3D application showcases. These instruments are further explained and presented in this paper. Der Beitrag beschreibt den aktuellen Stand des niederlandischen Projektes 3D Pilot NL und zugehorige Entwicklungen zur 3D-Datenmodellierung. Die erste Phase des Projektes fuhrte von Januar 2010 bis Juni 2011 zu einem nationalen 3D Standard, der als Application Domain Extension (ADE) von CityGML modelliert wurde. Fur seine Implementierung und Anwendung auf einen landesweiten 3D-Datensatz waren weitere Untersuchungen erforderlich. In der im Dezember 2012 beendeten zweiten Phase des 3D Pilot NL wurden Hilfsmittel fur die Implementierung entwickelt: 1.) eine Implementierungsrichtlinie der nationalen Application Domain Extension (ADE) fur City- GML zur Verwendung in Ausschreibungen, 2.) Beispieldatensatze, 3.) ein 3D Validator fur die Konsistenzprufung von Daten atzen, 4.) eine Richtlinie fur die Fortfuhrung der 3D Daten und 5.) Anwendungsbeispiele. Diese Werkzeuge werden hier vorgestellt.

A performance benchmark over semantic rule checking approaches in construction industry

As more and more architectural design and construction data is represented using the Resource Description Framework (RDF) data model, it makes sense to take advantage of the logical basis of RDF and implement a semantic rule checking process as it is currently not available in the architectural design and construction industry. The argument for such a semantic rule checking process has been made a number of times by now. However, there are a number of strategies and approaches that can be followed regarding the realization of such a rule checking process, even when limiting to the use of semantic web technologies. In this article, we compare three reference rule checking approaches that have been reported earlier for semantic rule checking in the domain of architecture, engineering and construction (AEC). Each of these approaches has its advantages and disadvantages. A criterion that is tremendously important to allow adoption and uptake of such semantic rule checking approaches, is performance. Hence, this article provides an overview of our collaborative test results in order to obtain a performance benchmark for these approaches. In addition to the benchmark, a documentation of the actual rule checking approaches is discussed. Furthermore, we give an indication of the main features and decisions that impact performance for each of these three approaches, so that system developers in the construction industry can make an informed choice when deciding for one of the documented rule checking approaches.

Qualitative and Quantitative Cost Estimation: A Methodology Analysis

This paper reports on the first part of an ongoing research with the goal of designing a framework and a knowledge-based system for 3D parametric modelbased quantity take-off and cost estimation in the Architecture, Engineering and Construction (AEC) industry. The authors have studied and analyzed current cost estimation methods used in both the AEC and non-AEC industries in terms of their requirements, use contexts, methodologies, limitations and strengths to lay the groundwork for selecting the most suitable problem decomposition methods and cost estimation techniques to design a new framework. We have focused on determining the underlying methodologies of different cost estimation models and not just the techniques. Both qualitative methods used in early stages of design and quantitative methods used in more mature design stages are reviewed and their structure are analyzed.

Freedom through constraints: User-oriented architectural design

In this article we report on validated research for the construction of design constraints by automated interpretation of natural language input. We show how our approach of dynamic reconfigurations of parsed syntax trees using a number of production rules is used to formalize and transform natural language constructs into computable constraints that are applied to concrete building information models. The calibration and validation of the proposed algorithms and production rules is based on two test data sets: The verbatim text of Dutch building code regulations for dormer extensions on existing roofs and constraints formulated ad hoc by design students based upon a series of example designs. We show how a prototypical implementation of our approach can be used to interpret 44% of the test data without human interference and how the remaining sentences can be interpreted with minimal additional effort or further development.