53 research outputs found

    AUTOMATED REGISTRATION OF BUILDING SCAN WITH BIM THROUGH DETECTION OF CONGRUENT CORNER POINTS

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    Current methods of construction progress monitoring involve manual data collection and processing, which are time-consuming and labor-intensive, with a dominant human presence entailing several flaws such as missing or inaccurate information. Recent research efforts for automated progress monitoring have largely focused on model-based assessment methods that are dependent on a pre-requisite step known as registration which is still performed manually due to numerous challenges. This study proposes a novel automated coarse registration method that utilizes the BIM model as the as-planned model to align it with the corresponding as-built model using their geometrical features. First, it extracts the corner points in both models using their planar features and then identifies the conjugate corner points based on different geometric invariants. Later, the transformations are determined from those conjugate points and the most accurate transformation parameter is finalized in the end. The proposed method is validated on different datasets

    Development of a 3D dynamic flood web GIS visualisation tool

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    Low elevation coastal areas are vulnerable to the effects of sea level rise and to an increase in the frequency and severity of storm surge events due to climate change.Coastal urban areas are at risk because coastal flooding causes extensive damage to energy and transportation infrastructure, disruptions to the delivery of services, devastating tolls on the public’s health and,occasionally, significant loss of life. Although scientists widely stress the compelling need to mitigate and adapt to climate change, public awareness lags behind. Because WebGIS maps (web-based geographic information systems) quickly convey strong messages, condense complex information, engage people on issues of environmental change, and motivate personal actions, this paper focuses on searching the ideal flood assessment WebGIS method to encourage people to mitigate and adapt to climate change. Surveys demonstrated that 3D visualisations have an enormous added value because they are more vivid and therefore more understandable and make it easier to imagine the consequences of a flood than2D visualisations. In this research, the WebGIS will be created using Ol3-Cesium and openlayers to visualise a flood event by dynamic layers in a 2D/3D environment

    The Next Linear Collider Test Accelerator

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    During the past several years, there has been tremendous progress on the development of the RF system and accelerating structures for a Next Linear Collider (NLC). Developments include high-power klystrons, RF pulse compression systems and damped/detuned accelerator structures to reduce wakefields. In order to integrate these separate development efforts into an actual X-band accelerator capable of accelerating the electron beams necessary for an NLC, we are building an NLC Test Accelerator (NLCTA). The goal of the NLCTA is to bring together all elements of the entire accelerating system by constructing and reliably operating an engineered model of a high-gradient linac suitable for the NLC. The NLCTA will serve as a testbed as the design of the NLC evolves. In addition to testing the RF acceleration system, the NLCTA is designed to address many questions related to the dynamics of the beam during acceleration. In this paper, we will report on the status of the design, component development, and construction of the NLC Test Accelerator

    How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers

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    Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program

    (4 MICROWAVE MEASUREMENTS OF AZIMUTHAL ASYMMETRIES IN ACCELERATING FIELDS OF DISK-LOADED WAVEGUIDES

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    This paper presents microwave measurements of azimuthal asymmctrics in the accelerating fields of the SLAC disk-loaded waveguide. These field asymmetries lead to RF phase-dependent beam steering which can be detrimental to operation of linear accelerators in general and of the SLAC Linear Collider in particular

    On-site geometrical measurements of an experimental ice composite shell through TLS and photogrammetry

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    Measurement techniques for determining the thickness and shape of ice structures can be divided into contact and non-contact methods. The non-contact methods are the most appropriate for measuring relatively thin fiber reinforced ice shells because they hold no risk for damages. Furthermore, these measurement techniques can be repeated during the icing process, which, additionally, enables to produce intermediate results. This paper describes the 3D measurement and modelling methods used for the “Candela pavilion” that was built by university students and staff in the framework of an international project in Juuka, Finland during the winter of early 2016.</p

    On-site geometrical measurements of an experimental ice composite shell through TLS and photogrammetry

    No full text
    Measurement techniques for determining the thickness and shape of ice structures can be divided into contact and non-contact methods. The non-contact methods are the most appropriate for measuring relatively thin fiber reinforced ice shells because they hold no risk for damages. Furthermore, these measurement techniques can be repeated during the icing process, which, additionally, enables to produce intermediate results. This paper describes the 3D measurement and modelling methods used for the “Candela pavilion” that was built by university students and staff in the framework of an international project in Juuka, Finland during the winter of early 2016

    HIGH-FIELD CAPTURE SECTION FOR SLC POSITRON SOURCE*

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    The positron source for SLC is being installed at the twe thirds point on the SLAC linac. Electron bunches at 33 GeV impinge upon a Tantalum/Tungsten target, producing showers of positrons with energies ’ extending from approximatel
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