Optimized biomimetic hair sensor arrays for sensing oscillating air flows

Artificial hair sensor arrays are bio-inspired from flow-sensitive filiform hairs of the crickets, one of nature’s best in sensing small air flows. The presented hair sensor arrays aim to realize higher sensitivities compared to our previous sensor arrays by means of model-based design optimizations and fabricated with advanced MEMS technologies. The artificial hair-sensor arrays display a clear figure-of-eight response and show remarkable sensitivities to oscillating air flows down to 0.85 mm/s surpassing noise levels even at 1 kHz operational bandwidths

Methodologies for requirement checking on building models:A technology overview

The use of Building Information Modelling (BIM) has increased in the Architectural and Urban domain. Stakeholders within distinct disciplines collaborate and exchange such information models digitally. In order to strive for an interoperable use of the models, requirement documents are being written by stakeholders, standardisation bodies and governments. Such documents pose additional requirements to the exchange of building model definitions and limit the scope of information to something that is relevant to the disciplines the exchange pertains to, the phase of the construction project and the level of development of the project. For effective collaboration processes, checking these requirements in an automated and unambiguous way is of crucial importance. Yet, requirement definitions often comprise natural language texts and academic and commercial tools being developed in this regard are fragmented and heterogeneous. Furthermore, the models being checked are of uncertain quality because the semantics of the schema are not rigorously formalized and enforced and models contain redundancies that affect their reliability. This paper urges for more developed schema semantics and illustrates how the body of technical means, such as classification system, concept libraries, query languages, reasoners and model view definitions are related to one another and to the concept of automated rule checking.</p

Methodologies for requirement checking on building models:A technology overview

The use of Building Information Modelling (BIM) has increased in the Architectural and Urban domain. Stakeholders within distinct disciplines collaborate and exchange such information models digitally. In order to strive for an interoperable use of the models, requirement documents are being written by stakeholders, standardisation bodies and governments. Such documents pose additional requirements to the exchange of building model definitions and limit the scope of information to something that is relevant to the disciplines the exchange pertains to, the phase of the construction project and the level of development of the project. For effective collaboration processes, checking these requirements in an automated and unambiguous way is of crucial importance. Yet, requirement definitions often comprise natural language texts and academic and commercial tools being developed in this regard are fragmented and heterogeneous. Furthermore, the models being checked are of uncertain quality because the semantics of the schema are not rigorously formalized and enforced and models contain redundancies that affect their reliability. This paper urges for more developed schema semantics and illustrates how the body of technical means, such as classification system, concept libraries, query languages, reasoners and model view definitions are related to one another and to the concept of automated rule checking.</p

Air-flow sensitive hairs: boundary layers in oscillatory flows around arthropod appendages

The aim of this work is to characterize the boundary layer over small appendages in insects in longitudinal and transverse oscillatory flows. The problem of immediate interest is the early warning system in crickets perceiving flying predators using air-flow-sensitive hairs on cerci, two long appendages at their rear. We studied both types of oscillatory flows around small cylinders using stroboscopic micro-particle image velocimetry as a function of flow velocity and frequency. Theoretical predictions are well fulfilled for both longitudinal and transverse flows. Transverse flow leads to higher velocities than longitudinal flow in the boundary layer over a large range of angles between flow and cylinder. The strong spatial heterogeneity of flow velocities around filiform-shaped appendages is a rich source of information for different flow-sensing animals. Our results suggest that crickets could perceive the direction of incoming danger by having air-flow-sensitive hairs positioned around their entire cerci. Implications for biomimetic flow-sensing MEMS are also presented

Geobim for digital building permit process: Learning from a case study in Rotterdam

Among the digitalization processes which are being raised in Europe and in the world, the building permit process is seen as one of the priorities by municipalities, governmental institutions and standardization organizations. However, in current practice, the building permit issuing as well as the integration of geoinformation with BIM (GeoBIM) suffers from a number of complex sub-issues. These issues still remain and prevent the development of successful methodologies. In this paper, the building permit use case is explored within a project in close collaboration with the municipality of Rotterdam. A very specific case study in Rotterdam was selected as a starting point, which allowed us to develop the needed methodology for the implementation of an effective tool. In this paper we highlight the interpretation and formalization of regulation for building height, overhang and tower ratio. While these rules are specific to a zoning plan in Rotterdam, we believe that the methodology and encountered issues in formalizing the rules, applying the rules on delivered models and integrating various data sources (BIM and GIS specifically) are general to most building codes

Tissue identification with micro-magnetic resonance imaging in a caprine spinal fusion model

Nonunion is a major complication of spinal interbody fusion. Currently X-ray and computed tomography (CT) are used for evaluating the spinal fusion process. However, both imaging modalities have limitations in judgment of the early stages of this fusion process, as they only visualize mineralized bone. Magnetic resonance imaging (MRI) could be of great value as it is able to discriminate between different types of tissue. A feasibility study was performed in nine animals from a goat spinal fusion study, to evaluate the detection capacity of different tissues with micro-MRI. In this study bioresorbable polylactic acid cages were used. Six- and 12-months follow-up specimens were scanned in a 6.3 T micro-MRI scanner. After scanning, the specimens were processed for histology. Different types of tissue as well as the degradable cage material were identified in the fusion zone and designated as regions of interest (ROIs). Subsequently, the location of these ROIs was determined on the corresponding micro- MRI image, and average signal intensities of every individual ROI were measured. An excellent match was seen between the histological sections and micro-MRI images. The micro-MRI images showed quantifiable differences in signal intensity between bone with adipose marrow, bone with hematopoietic marrow, fibrocartilage, fibrous tissue, and degradable implant material. In time the signal intensity of bone with adipose marrow, bone with hematopoietic red marrow, and of fibrous tissue remained relatively constant. On the other hand, the signal intensity of the degradable implant material and the fibrocartilage changed significantly in time, indicating change of structure and composition. In conclusion, in our model using bioresorbable cages the MRI provides us with detailed information about the early fusion process and may therefore, allow early diagnosis of non-union

Geobim benchmark 2019: Design and initial results

GeoBIM, the integration of 3D geoinformation (Geo) with building information models (BIM), is a subject of increasing attention in both domains. A well-known practical challenge for this integration is the mixed state of software support for open standards in each domain that would ease the integration. This is often known by practitioners but poorly documented. In order to solve this problem, we devised the GeoBIM benchmark, in which we compile the experiences of volunteering participants, who perform a guided study to test the software they are most familiar with against a few provided datasets structured in open standards. The aim of the tests is to improve the knowledge of the state of the art in the software support for GeoBIM open standards and to identify points for improvement. In this paper, we present the design of the benchmark, especially explaining and discussing the chosen data to be used with their connected issues to be tested, and some initial results

THE ISPRS-EUROSDR GEOBIM BENCHMARK 2019

Standardised data formats and data models are essential for data integration and interoperability, which in turn adds value to data by allowing its reuse in multiple contexts. For this reason, in recent years extensive efforts have been focused on standards development. When representing the built environment, 3D city models and Building Information Models are particularly relevant, and their integration is now required to underpin use cases that cover the full life-cycle of a built asset, including design and planning as well as operations and management, and to support legal applications such as cadastral systems. For those kinds of data, CityGML by the Open Geospatial Consortium and Industry Foundation Classes by buildingSMART are the most popular reference standards. However, many users report, often through informal channels, the difficulties of working with these formats. This paper summarizes the outcomes of the GeoBIM Benchmark 2019, a scientific initiative funded by ISPRS and EuroSDR to collect insights into the most relevant issues encountered in the management of CityGML and IFC within existing software. Alongside data management (import, visualisation, analysis, export) problems, issues of particular consequence in terms of integration relate to georeferencing IFC files and the conversions among the two kinds of formats and models. Thus, the benchmark was designed to explore these tasks in available software. Following analysis of the benchmark results, a key outcome is the impossibility to find clear patterns in the behaviour of tools, which consequently means there is no consistency in the implementation of standards. Although the results could seem disappointing, the criticality in managing these standards as they are was described and this awareness can be the starting point for further research or further standards development. Finally, this project was useful to gather a wide community around this topic, and the discussion about the GeoBIM-related issues was definitely pushed