A Web-platform for Linking IFC to External Information during the Entire Lifecycle of a Building

AbstractDuring the lifecycle of a building, much more information is used and produced than can be contained inside a Building Information Model (BIM). The information outside the BIM is seldom connected to the BIM or connected across domains. Furthermore, information in BIM is only accessible to people with sufficient CAD or architectural background, and often expensive software is needed to edit and add data. This inefficient information management causes significant costs in practice. Our research contributes to the development of IFC based web applications in practice and demonstrates a way of linking machine to human readable data thus making the data accessible to non CAD users or architectural experts. In this paper we describe such a platform for the integration of model-based data and non-model based data. We tried to construct a mapping process from IFC properties to a national building element classification system, as a way of structuring the objects and information for use in our web platform. Since both the structure of IFC and most building element classification systems are based on semantic relations of building elements (i.e. holonym, meronym, hypernym), translations by means of a basic reasoning system should be feasible. We elaborate on several uses of this platform in applications for maintenance and reuse of building materials, buildings and built structures

Immobilization precision of a modified GTC frame

The purpose of this study was to evaluate and quantify the interfraction reproducibility and intrafraction immobilization precision of a modified GTC frame. The error of the patient alignment and imaging systems were measured using a cranial skull phantom, with simulated, predetermined shifts. The kV setup images were acquired with a room‐mounted set of kV sources and panels. Calculated translations and rotations provided by the computer alignment software relying upon three implanted fiducials were compared to the known shifts, and the accuracy of the imaging and positioning systems was calculated. Orthogonal kV setup images for 45 proton SRT patients and 1002 fractions (average 22.3 fractions/patient) were analyzed for interfraction and intrafraction immobilization precision using a modified GTC frame. The modified frame employs a radiotransparent carbon cup and molded pillow to allow for more treatment angles from posterior directions for cranial lesions. Patients and the phantom were aligned with three 1.5 mm stainless steel fiducials implanted into the skull. The accuracy and variance of the patient positioning and imaging systems were measured to be 0.10±0.06 mm, with the maximum uncertainty of rotation being ±0.07°.957 pairs of interfraction image sets and 974 intrafraction image sets were analyzed. 3D translations and rotations were recorded. The 3D vector interfraction setup reproducibility was 0.13 mm ±1.8 mm for translations and the largest uncertainty of ±1.07° for rotations. The intrafraction immobilization efficacy was 0.19 mm ±0.66 mm for translations and the largest uncertainty of ±0.50° for rotations. The modified GTC frame provides reproducible setup and effective intrafraction immobilization, while allowing for the complete range of entrance angles from the posterior direction. PACS number: 87.53.Ly, 87.55.Q

Regional scale spatio-dynamic simulation of hydrological pathways and groundwater transit times for diffuse pollution modelling in a lowland catchment

Hydrological connectivity is nowadays recognized as a key factor controlling the transfer of nutrients throughout the landscape. At the regional (100 - 10000 km2) scale, current rasterbased nutrient transport models fail to describe hydrological pathways in both space and time, because their resolution is too low. We developed a novel modelling approach, which is based on a cell-by-cell water balance model and a GIS-implementation of existing equations describing groundwater storage and runoff as governed by recharge and landscape metrics and groundwater transit times. The model was applied to an Estonian lowland catchment measuring 901 km2 for the years 1991-2000 and calibrated using 7-days mean discharge at the catchment outlet. The value of the improved dynamic simulation of magnitude and spatial extent of both quick and slow hydrological pathways was successfully tested by exploring the relations between measured Dissolved Inorganic Nitrogen (DIN) concentrations and simulated 'hydrological states' of the catchments during a typical summer baseflow, in which we hypothesized that concentrations are governed by low transit times and agricultural areas, and during a typical spring flood, in which the share of quick runoff from agricultural areas seems dominant

Immobilization precision of a modified GTC frame

The purpose of this study was to evaluate and quantify the interfraction reproducibility and intrafraction immobilization precision of a modified GTC frame. The error of the patient alignment and imaging systems were measured using a cranial skull phantom, with simulated, predetermined shifts. The kV setup images were acquired with a room-mounted set of kV sources and panels. Calculated translations and rotations provided by the computer alignment software relying upon three implanted fiducials were compared to the known shifts, and the accuracy of the imaging and positioning systems was calculated. Orthogonal kV setup images for 45 proton SRT patients and 1002 fractions (average 22.3 fractions/patient) were analyzed for interfraction and intrafraction immobilization precision using a modified GTC frame. The modified frame employs a radiotransparent carbon cup and molded pillow to allow for more treatment angles from posterior directions for cranial lesions. Patients and the phantom were aligned with three 1.5 mm stainless steel fiducials implanted into the skull. The accuracy and variance of the patient positioning and imaging systems were measured to be 0.10 +/- 0.06 mm, with the maximum uncertainty of rotation being +/- 0.07 degrees. 957 pairs of interfraction image sets and 974 intrafraction image sets were analyzed. 3D translations and rotations were recorded. The 3D vector interfraction setup reproducibility was 0.13 mm +/- 1.8 mm for translations and the largest uncertainty of +/- 1.07 degrees for rotations. The intrafraction immobilization efficacy was 0.19 mm +/- 0.66 mm for translations and the largest uncertainty of +/- 0.50 degrees for rotations. The modified GTC frame provides reproducible setup and effective intrafraction immobilization, while allowing for the complete range of entrance angles from the posterior directio

Development of Non-Cell Adhesive Vascular Grafts Using Supramolecular Building Blocks

Cell-free approaches to in situ tissue engineering require materials that are mechanically stable and are able to control cell-adhesive behavior upon implantation. Here, the development of mechanically stable grafts with non-cell adhesive properties via a mix-and-match approach using ureido-pyrimidinone (UPy)-modified supramolecular polymers is reported. Cell adhesion is prevented in vitro through mixing of end-functionalized or chain-extended UPy-polycaprolactone (UPy-PCL or CE-UPy-PCL, respectively) with end-functionalized UPy-poly(ethylene glycol) (UPy-PEG) at a ratio of 90:10. Further characterization reveals intimate mixing behavior of UPy-PCL with UPy-PEG, but poor mechanical properties, whereas CE-UPy-PCL scaffolds are mechanically stable. As a proof-of-concept for the use of non-cell adhesive supramolecular materials in vivo, electrospun vascular scaffolds are applied in an aortic interposition rat model, showing reduced cell infiltration in the presence of only 10% of UPy-PEG. Together, these results provide the first steps toward advanced supramolecular biomaterials for in situ vascular tissue engineering with control over selective cell capturin

Average mussel bed densities in the Wadden Sea

<p>This is figure 1 from our open access Ecosystems paper: Large-Scale Spatial Dynamics of Intertidal Mussel (<em>Mytilus edulis</em> L.) Bed Coverage in the German and Dutch Wadden Sea. It describes the 39 tidal basins of the Wadden Sea with average intertidal mussel bed coverage over the years 1999–2010. Intertidal mussel bed coverage is defined as the percentage of tidal flat area that is covered by mussel beds. The intertidal flats in tidal basins 1–3 in Denmark are colored gray because no comparable mussel bed data were available. The geographic extent of the Wadden Sea ranges between 52°57–55°37 North and 4°44–8°12 East.</p> <p> </p

Probing the solvent-induced tautomerism of a redox-active ureidopyrimidinone

Trimethylammonium functionalized gold nanoparticles are demonstrated as templates for the assembly of peptide fragments and their subsequently promoted ligation. This system displays the use of organically tailored nanoparticles as effective supramolecular reagents for catalyzing bond-forming reactions and may also serve as a model for prebiotic conditions where charged surfaces may have promoted the polymerization of the early biopolymers