Towards BIM/GIS interoperability: A theoretical framework and practical generation of spaces to support infrastructure Asset Management

The past ten years have seen the widespread adoption of Building Information Modelling (BIM) among both the Architectural, Engineering and Construction (AEC) and the Asset Management/ Facilities Management (AM/FM) communities. This has been driven by the use of digital information to support collaborative working and a vision for more efficient reuse of data. Within this context, spatial information is either held in a Geographic Information Systems (GIS) or as Computer-Aided Design (CAD) models in a Common Data Environment (CDE). However, these being heterogeneous systems, there are inevitable interoperability issues that result in poor integration. For this thesis, the interoperability challenges were investigated within a case study to ask: Can a better understanding of the conceptual and technical challenges to the integration of BIM and GIS provide improved support for the management of asset information in the context of a major infrastructure project? Within their respective fields, the terms BIM and GIS have acquired a range of accepted meanings, that do not align well with each other. A seven-level socio-technical framework is developed to harmonise concepts in spatial information systems. This framework is used to explore the interoperability gaps that must be resolved to enable design and construction information to be joined up with operational asset information. The Crossrail GIS and BIM systems were used to investigate some of the interoperability challenges that arise during the design, construction and operation of an infrastructure asset. One particular challenge concerns a missing link between AM-based information and CAD-based geometry which hinders engineering assets from being located within the geometric model and preventing geospatial analysis. A process is developed to link these CAD-based elements with AM-based assets using defined 3D spaces to locate assets. However, other interoperability challenges must first be overcome; firstly, the extraction, transformation and loading of geometry from CAD to GIS; secondly, the creation of an explicit representation of each 3D space from the implicit enclosing geometry. This thesis develops an implementation of the watershed transform algorithm to use real-world Crossrail geometry to generate voxelated interior spaces that can then be converted into a B-Rep mesh for use in 3D GIS. The issues faced at the technical level in this case study provide insight into the differences that must also be addressed at the conceptual level. With this in mind, this thesis develops a Spatial Information System Framework to classify the nature of differences between BIM, GIS and other spatial information systems

Effect of priming exercise on oxygen uptake kinetics in heart failure with preserved ejection fraction

The cardinal symptom of heart failure with preserved ejection fraction (HFpEF) is exercise intolerance, which is associated with fatigue and reduced quality of life. HFpEF patients exhibit skeletal muscle dysfunction related to reduced peak oxygen uptake (peak V̇O2p). Prior heavy exercise speeds pulmonary oxygen uptake (V̇O2p) kinetics in older adults and in HF patients with reduced ejection fraction (HFrEF), presumably through increased oxygen delivery to the exercising muscle. We tested the hypothesis that prior heavy exercise would not speed V̇O2p on-kinetics in patients with HFpEF, suggesting HFpEF exercise intolerance stems primarily from muscle dysfunction. Eight HFpEF patients, 4 high-fit (CTL-HF), and 5 low-fit age-matched controls (CTL-LF) underwent echocardiography and peak exercise testing (cycle ergometer). Subjects performed 3 separate repetitions of 2 exercise transitions: MOD1, transition from rest to 4-min moderate intensity cycling (work rate corresponding to 90% ventilatory threshold); and MOD2, MOD1 preceded by 2-min of heavy cycling (∆50% intensity; halfway between ventilatory threshold and peak) and 5-min of inter-transition rest. V̇O2p (breath-by-breath gas exchange), heart rate (HR, ECG), stroke volume (SV, ModelFlow), cardiac output (CO, calculated), total peripheral resistance (TPR, calculated), and tissue oxygenation of the vastus lateralis (TOI, near-infrared spectroscopy) on-kinetics were measured. V̇O2p, HR, and CO data were linearly interpolated, time-aligned, averaged into 5-s time bins, and curve-fitted using a monoexponential equation. ∆SV, ∆TPR, and ∆TOI were calculated from baseline at 15s, 30s, and end-exercise to represent time-course changes. Analysis included repeated measures ANOVA, and SNK post-hoc, break-down analyses, and non-parametric testing where appropriate. Significance was P<0.05. HFpEF V̇O2p on-kinetics were slower than CTL-HF but similar to CTL-LF, pooled across conditions (P=0.008). MOD2 V̇O2p on-kinetics were faster compared to MOD1, pooled across groups (P=0.039). CTL-HF had a greater reduction in TPR across all time points compared to HFpEF (all P<0.038) and at 30s and end-exercise compared to CTL-LF (all P<0.032), pooled across conditions. HFpEF patients and CTL-LF had decreased TOI at 15-30s (all P≤0.024) in MOD1. By visual inspection, HFpEF TOI remained depressed while CTL-LF TOI increased to baseline levels, with no group difference at end-exercise (P=0.086) in MOD1. CTL-HF TOI increased at 15-30s (all P≤0.024) and decreased toward baseline levels. All groups had slower HR on-kinetics in MOD2 compared to MOD1 (P=0.001). TOI showed a greater reduction in MOD2 than MOD1 in HFpEF at 30s (P=0.033) and CTL-HF throughout MOD2 (all P<0.05). The results of this study indicate that HFpEF patients have impaired V̇O2p on-kinetics and a speeding response of V̇O2p on-kinetics to prior exercise, suggesting O2 delivery may be an important rate-limiting factor of V̇O2p on-kinetics in HFpEF

Fast pseudo-enhancement correction in CT colonography using linear shift-invariant filters

This paper presents a novel method to approximate shift-variant Gaussian filtering of an image using a set of shift-invariant Gaussian filters. This approximation affords filtering of the image using fast convolution techniques that rely on the FFT, while achieving a result that closely matches the shift-variant result. We demonstrate the method in a CT colonography application that reduces the pseudo-enhancement effect, which is a local brightening artifact in CT imaging that can result from the use of oral contrast agents. Experimental results demonstrate the effectiveness of the method and emphasize its computational efficiency

Developing IFC for infrastructure: A case study of three highway entities

Modern cities pay particular attention to upscale their infrastructure systems in order to improve the every-day life of their citizens and lead the way towards a more sustainable environment. As part of this, they invest extensive funds in large infrastructure projects which are challenging to deliver as they require an e efficient communication among different professions, in order to share information efficiently throughout the lifecycle of the project, thus highlighting the importance of standardization to maintain consistency and integrity during data exchange. Building Information Modelling (BIM) aims to facilitate the above-mentioned requirements by describing the life-cycle of the project and Industry Foundation Classes (IFC) is the Standard for BIM that enables an efficient storage, management, exchange and visualization of information. However, there are two important challenges that need to be addressed: (i) IFC focuses particularly on buildings and provides limited support for infrastructure elements and (ii) the information exchange aims to describe mostly the construction phase; highlighting the lack of classes that refer to the operation and maintenance phase. Within this context, this paper proposes the extension of Industry Foundation Classes (IFC) for Asset Management in Infrastructure. A method is developed based on a case study of three highway entities: (i) retaining wall, (ii) gantry and (iii) bridge and a conceptual extension is presented. The results are further discussed and recommendations regarding future research fields are proposed

Accommodation needs for carers of and adults with intellectual disability in regional Australia: Their hopes for and perceptions of the future

Introduction: This article provides an in-depth investigation of the accommodation circumstances of a population of aging adults with intellectual disability living at home with parents or in supported accommodation in an Australian regional centre. Given the ageing of both the carer and adult population with intellectual disability our research explored the accommodation needs and perceptions of future lifestyle issues from the perspective of both the carers and the adults with intellectual disability. This study aimed to describe these accommodation circumstances related to a regional/rural location and did not make direct comparisons with urban/metropolitan situations. Methods: A mixed methods approach, specifically an explanatory design, participant selection model was utilised for the overall study. This article reports on the qualitative study consisting of data from both free response open-ended survey questions and semi-structured interviews with selected adults with intellectual disability and their carers. This study explored and described participants’ experiences and perceptions regarding their accommodation needs and future lifestyle issues. A purposive sampling technique was used to identify a representative sample of participants for interviews. The interview questions were guided by the results of the quantitative first study phase. Data were analysed by content analysis for major themes emerging from the interview and free response survey data. Results: A total of 146 carers (mean age 61.5 years; range 40–91 years) and 156 adults with intellectual disability (mean age 37.2 years; range 18–79 years) participated in the study. Data saturation was reached after 10 interviews were undertaken with carers (mean age 60 years) and 10 with adults with intellectual disability (no age criteria applied). Six major themes were identified: ageing, family issues, living at home, living away from home, government support and funding, and future needs. The perceptions and views of both adults with intellectual disability and their carers around these major themes are reported and discussed. Conclusions: This study indicates that there is a lack of suitable, available, supported accommodation for people aged 18 years and older with intellectual disability in this Australian regional centre. Consequently, aging parents caring at home have little choice but to continue in their caring role. For those caring away from home, existing services are decreasingly seen as fitting the ideal life they want for the person with intellectual disability for whom they care. The told experiences, perceptions and views of older carers of and adults with intellectual disability have highlighted their increasing vulnerability to the ‘disability system’. The findings suggest that government and disability services must acknowledge the changing needs of people with intellectual disability in connection with their advancing age and the urgency of increasing care needs due to the advancing age of their carer/s. The overwhelming feeling is that the carer’s voice will only be heard when the situation reaches crisis point. For many carers and their families this has already occurred

Thermorheological Properties Near the Glass Transition of Oligomeric Poly(methyl methacrylate) Blended with Acrylic Polyhedral Oligomeric Silsesquioxane Nanocages

Submitted to Rheologica ActaTwo distinct oligomeric species of similar mass and chemical functionality (Mw ≈ 2,000 g/mol), one a linear methyl methacrylate oligomer (radius of gyration Rg ≈ 1.1 nm) and the other a hybrid organic-inorganic polyhedral silsesquioxane nanocage (methacryl-POSS, r ≈ 1.0 nm), were subjected to thermal and rheological tests to compare the behaviors of these geometrically dissimilar molecules over the entire composition range. The glass transition temperatures of the blends varied monotonically between the glass transition temperatures of the pure oligomer (Tg = â47.3°C) and the pure POSS (Tg = â61.0°C). Blends containing high POSS contents (with volume fraction φ_POSS ⥠0.90) exhibited enhanced enthalpy relaxation in DSC measurements, and the degree of enthalpy relaxation was used to calculate the kinetic fragility indices m of the oligomeric MMA (m = 59) and the POSS (m = 74). The temperature dependences of the viscosities were fitted by the free volume-based WLF-VFT framework and a dynamic scaling relation. The calculated values of the fragility from the WLF-VFT fits were similar for the POSS (m = 82) and for the oligomer (m = 76), and the dynamic scaling exponent was similar for the oligomeric MMA and the POSS. Within the range of known fragilities for glass-forming liquids, the temperature dependence of the viscosity was found to be similarly fragile for the two species. The difference in shape of the nanocages and oligomer chains is unimportant in controlling the glass-forming properties of the blends at low volume fractions ( φPOSS < 0.20); however, at higher volume fractions, adjacent POSS cages begin to crowd each other, leading to an increase in the fractional free volume at the glass transition temperature and the observed enhanced enthalpy relaxation in DSC.AFOSR (DURINT Program

Linking tree growth rate, damage repair, and susceptibility to a genus-specific pest infestation

Pest preference and subsequent susceptibility of a host individual is likely related to previous growth patterns in that host. Emerald ash borer (Agrilus planipennis Fairmaire) is a pestiferous beetle introduced to North America from Asia. While all species of ash are susceptible to attack, some individual trees appear to survive infestation. We selected ash trees in southeastern Michigan, collected cores and categorized trees as high tolerance to emerald ash borer attack (high overall health, low crown dieback), low tolerance (low overall health, high crown dieback) and intermediate tolerance (in-between the other categories). We artificially wounded trees and measured wound closure after 3 years. Ring width indices were not correlated between high and low tolerance trees. Regression slopes comparing growth and years were significantly different between the three tolerance categories, with high tolerance trees having the steepest slope. Wound closure was greatest in high tolerance trees. High tolerance trees demonstrating more rapid (steeper regression slope), consistent (lower variance), and effective (greater wound closure) growth. Those vigorously growing trees likely had more capacity to repair damage caused by emerald ash borer, leading to healthier trees in our categorization. Linking previous host growth patterns to health may have implications related to identifying individual trees potentially tolerant to attack

Exploring the Effectiveness of a Retreat Method for Extension Staff

The California 4-H Association hosted two retreats to support its members with goals of balancing professional development with intentional relationship building. Evaluations demonstrated that staff found the intentional balance of time spent in unstructured, semi-structured, and structured time offered opportunities to grow professionally while building relationships with peers. Follow-up surveys found that 4-H professionals strengthened their network of peers to rely on in their work. Future work for professional development may benefit from a social capital lens