1,115 research outputs found

    A framework for integrating syntax, semantics and pragmatics for computer-aided professional practice: With application of costing in construction industry

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    Producing a bill of quantity is a knowledge-based, dynamic and collaborative process, and evolves with variances and current evidence. However, within the context of information system practice in BIM, knowledge of cost estimation has not been represented, nor has it been integrated into the processes based on BIM. This paper intends to establish an innovative means of taking data from the BIM linked to a project, and using it to create the necessary items for a bill of quantity that will enable cost estimation to be undertaken for the project. Our framework is founded upon the belief that three components are necessary to gain a full awareness of the domain which is being computerised; the information type which is to be assessed for compatibility (syntax), the definition for the pricing domain (semantics), and the precise implementation environment for the standards being taken into account (pragmatics). In order to achieve this, a prototype is created that allows a cost item for the bill of quantity to be spontaneously generated, by means of the semantic web ontology and a forward chain algorithm. Within this paper, ‘cost items’ signify the elements included in a bill of quantity, including details of their description, quantity and price. As a means of authenticating the process being developed, the authors of this work effectively implemented it in the production of cost items. In addition, the items created were contrasted with those produced by specialists. For this reason, this innovative framework introduces the possibility of a new means of applying semantic web ontology and forward chain algorithm to construction professional practice resulting in automatic cost estimation. These key outcomes demonstrate that, decoupling the professional practice into three key components of syntax, semantics and pragmatics can provide tangible benefits to domain use

    Capital Budgeting Evaluation Practices of Building Contractors in Hong Kong

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    This paper reports the results of an investigation into capital budgeting evaluation practicesin the construction industry of Hong Kong. The aim of this study was to identify thepopularity and extent of usage of various techniques for capital budget evaluation, investmentappraisal, risk analysis, and management science. The current study was comparedwith a similar survey conducted in 1994 to establish the changes in the capital budgetingevaluation practices of contracting firms over time. The results indicate that there was ageneral increase in the popularity and extent of usage in certain capital budget evaluationtechniques such as “best/worst estimate” and “formal financial evaluation”. In addition,the evaluation techniques examined were fitted into a discriminant function analysis (DFA),and a model has been developed which allows contracting firms to be classified accordingto their predominant characteristics in capital budget evaluation

    Proteomic analysis of the rat ovary following chronic low-dose exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

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    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a ubiquitously distributed endocrine-disrupting chemical and reproductive toxicant. In order to elucidate low-dose TCDD-mediated effects on reproductive or endocrine functions, female Sprague-Dawley rats were orally administered various concentrations (20, 50, or 125 ng/kg once weekly) TCDD for 29 wk. A proteomic analysis of the ovaries by two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry showed distinct changes in the levels of several proteins that are relevant markers of TCDD toxicity. Serum estradiol (E2) levels of TCDD-treated animals were markedly lower than control. There were no significant differences in bone mineral density (BMD) of femurs. The body weight of the 125-ng/kg TCDD group was significantly decreased relative to control and there was also a significant reduction in absolute and relative ovarian weights. Expressions of selenium binding protein 2, glutathione S-transferase mu type 3, Lrpap1 protein, NADPH, and peptidylprolyl isomerase D were upregulated, while prohibitin and N-ethylmaleimide-sensitive factor expression levels were downregulated. Data provide further insight into the mechanisms by which TCDD disrupts ovarian function by indicating which differential protein expressions following low-dose TCDD exposure

    ANALYSIS OF THE PRESSURE DISTRIBUTION PATTERN AND THE CONTROLLING BALANCE DURING KICK MOVEMENT OF TAI-CHI CHUAN

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    The purpose of this study was to compare the pressure distribution patterns of the stable kick and unstable kick from the kick movement of a Tai-Chi Chuan athlete. A national elite female Tai-Chi Chuan athlete was the subject for this study. The Tekscan HR Mat Pressure Measurement System was used to collect the vertical ground reaction force and the pressure history of the standing foot in right kicking movement and left kicking movement. All the data of the standing foot were divided into metatarsals, tarsals and phalanges to calculate the partial force and partial pressure. The pressure-time diagram of the phalanges, metatarsals and tarsals indicated that the pressure histories trended to be stable in each time as the lefl kick completed, and the phalanges produced 'snatchy' and larger pressures acting on the ground

    Transport spectroscopy in a time-modulated open quantum dot

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    We have investigated the time-modulated coherent quantum transport phenomena in a ballistic open quantum dot. The conductance GG and the electron dwell time in the dots are calculated by a time-dependent mode-matching method. Under high-frequency modulation, the traversing electrons are found to exhibit three types of resonant scatterings. They are intersideband scatterings: into quasibound states in the dots, into true bound states in the dots, and into quasibound states just beneath the subband threshold in the leads. Dip structures or fano structures in GG are their signatures. Our results show structures due to 2ω\hbar\omega intersideband processes. At the above scattering resonances, we have estimated, according to our dwell time calculation, the number of round-trip scatterings that the traversing electrons undertake between the two dot openings.Comment: 8 pages, 5 figure

    Project-based pedagogy in interdisciplinary building design adopting BIM

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    Purpose – This study aims to present a pedagogical practice in the project-based assessment of AEC students’ interdisciplinary building design work adopting BIM. This pedagogical practice emphasizes the impacts of BIM, as the digital collaboration platform, on the cross-disciplinary teamwork design through information sharing. This study also focuses on collecting students’ perceptions of BIM effects in integrated project design. Challenges in BIM adoption from AEC students’ perspective were identified and discussed, and could spark further research needs. Design/Methodology/Approach – Based on a thorough review of previous pedagogical practices of applying BIM in multiple AEC disciplines, this study adopted a case study of the Solar Decathlon residential building design as the group project for AEC students to deliver the design work and construction planning. In total 13 different teams within the University of Nottingham Ningbo China, each group consisting of final year undergraduate students with backgrounds in architecture, civil engineering, and architectural environmental engineering, worked to deliver the detailed design of the solar-powered residential house meeting pre-specified project objectives in terms of architectural aesthetics, structural integrity, energy efficiency, prefabrication construction techniques, and other issues such as budget and scheduling. Each team presented the cross-disciplinary design plan with cost estimate and construction scheduling together with group reports. This pedagogical study collected students’ reflective thinking on how BIM affected their design work, and compared their feedback on BIM to that from AEC industry professionals in previous studies. Findings – The case study of the Solar Decathlon building project showed the capacity of BIM in enabling interdisciplinary collaboration through information exchange and in enhancing communication across different AEC fields. More sustainable design options were considered in the early architectural design stages through the cross-disciplinary cooperation between architecture and building services engineering. BIM motivated AEC student teams to have a more comprehensive design and construction plan by considering multiple criteria including energy efficiency, budget, and construction activities. Students’ reflections indicated both positive effects of BIM (e.g., facilitating information sharing) as well as challenges for further BIM implementation, such as some architecture students’ resistance to BIM, and the lack of existing family types in the BIM library, etc. Research limitations/implications – Some limitations of the current BIM pedagogy were identified through the student group work. For example, students revealed the problem of interoperability between BIM (i.e., Autodesk Revit) and building energy simulation tools. To further integrate the university education and AEC industry practice, future BIM pedagogical work could recruit professionals and project stakeholders in the adopted case studies, for the purpose of providing professional advice on improving the constructability of the BIM-based design from student work. Originality/value – This work provides insights into the information technology applied in the AEC interdisciplinary pedagogy. Students gained the experience of a project-based collaboration and were equipped with BIM capabilities for future employment within the AEC job market. The integrated design approach was embedded throughout the team project process. Overall, this BIM pedagogical practice emphasized the link between academic activities and real-world industrial practice. The pedagogical experience gained in this BIM course could be expanded to future BIM education and research in other themes such as interoperability of building information exchange among different digital tools

    Dynamic Image-Based Modelling of Kidney Branching Morphogenesis

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    Kidney branching morphogenesis has been studied extensively, but the mechanism that defines the branch points is still elusive. Here we obtained a 2D movie of kidney branching morphogenesis in culture to test different models of branching morphogenesis with physiological growth dynamics. We carried out image segmentation and calculated the displacement fields between the frames. The models were subsequently solved on the 2D domain, that was extracted from the movie. We find that Turing patterns are sensitive to the initial conditions when solved on the epithelial shapes. A previously proposed diffusion-dependent geometry effect allowed us to reproduce the growth fields reasonably well, both for an inhibitor of branching that was produced in the epithelium, and for an inducer of branching that was produced in the mesenchyme. The latter could be represented by Glial-derived neurotrophic factor (GDNF), which is expressed in the mesenchyme and induces outgrowth of ureteric branches. Considering that the Turing model represents the interaction between the GDNF and its receptor RET very well and that the model reproduces the relevant expression patterns in developing wildtype and mutant kidneys, it is well possible that a combination of the Turing mechanism and the geometry effect control branching morphogenesis
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