A network theoretic perspective of decision processes in complex construction projects

This paper proposes an approach to modelling and visualising decision processes in large complex construction projects by incorporating a network perspective. Computer modelling and visualisation of decision processes as social and task-entity networks makes possible the identification of key participants, critical tasks, latent networks, vulnerabilities and dynamics that impact upon complex decision situations. New advances in network theory can help reveal the ways in which social, organisational, political and technological relationships shape decision outcomes. By conceiving decision processes as a complex system and modelling this system using network-theoretic principles, it is possible to include a tremendous amount of information that has remained untapped by conventional qualitative, game-theoretic, and statistical approaches. This research contributes to the understanding of the strategic implications of decision processes as complex systems of interacting actors and problem tasks, and provides the technological means for supporting them. The approach has been verified through the development of an experimental network-theoretic system

Exploring the value of BIM for corporate real estate

© 2016, © Emerald Group Publishing Limited. Purpose: Building information modelling (BIM) offers rich opportunities for property professionals to use information throughout the property life cycle. However, the benefits of BIM for property professionals are largely untapped. BIM was developed by the architecture, engineering and construction (AEC) sector to assist in managing design and construction data. As these technologies mature and evolve, so does the opportunity for other professional groups to use data within, or linked to, BIM models. This paper aims to explore the potential for corporate real estate managers (CREM) and investment surveyors to use data contained in BIM models and building management systems, which could help these professionals with strategic planning, portfolio rationalisation and acquisitions. Design/methodology/approach: This is a scoping study to explore the potential to expand the scope of BIM to other professional activities. As such, the research adopted a Delphi approach with a series of workshops with experienced stakeholders in Australia and England. Qualitative research is inductive and hypothesis-generating. That is, as the researcher assimilates knowledge and information contained in the literature, ideas and questions are formed, which are put to research participants, and, from this process, conclusions are drawn. Findings: It is technologically feasible for some property professionals, such as CREM, to use some data contained within BIM, and linked building management systems. The types of data used by property professionals were identified and ranked in importance. Needs are varied, both in the range of data and the points in the property life cycle when they are required. The benefits identified include potentially accessing and using more reliable and accurate data in professional tasks; however, challenges exist around the fidelity of the data and assurances that it is current. Research limitations/implications: The key limitations of the research were that the views expressed are those of a select group of experienced practitioners and may not represent the consensus view of the professions and industry as a whole. The limitations and criticisms of focus group data collection are that individuals holding strong views may dominate the sessions. Practical implications: The findings show that expanding access to BIM could enable some property professionals, including CREM, to utilise relevant data that could improve the quality and accuracy of their professional services. A simple initial system could be trialled to ascertain the value of the data. Over time, the availability of data could be extended to allow more professionals access. Furthermore, there is potential to link BIM to other digitised property data in the future. Originality/value: To date, no one has considered the practicality or potential utility of expanding the access to data contained in 3D BIM models to property professionals, nor has anyone considered which data would be useful to them. The value of using BIM data is that, as more property stock is delivered and maintained via BIM-enabled processes, it will be possible for a wider range of professionals such as CREM and investment surveyors to offer more accurate advice and services to clients

Building Information Modelling in Tertiary Construction Project Management Education: A Programme-wide Implementation Strategy

This paper reports on the on-going development of teaching and learning supported by Building Information Modelling (BIM) in the undergraduate Construction Project Management Programme at the University of Technology Sydney. BIM is a model-driven approach to designing, constructing, operating and maintaining buildings and civil engineering facilities. The model that forms the core of the BIM approach is a smart, shared and computable three-dimensional model of the building or the civil engineering facility. At its heart, BIM and Virtual Construction Models (VCMs) are used to facilitate a more integrated and visual mode of teaching. The approach provides a new basis for developing problem based learning - one that has the potential to allow students to aggregate their learning around a central project whilst enabling problems to be scaled at different levels of complexity. This approach aims to better integrate and link individual subjects together as well as improve the development of core student attributes such as communication, understanding, decision making, collaboration and information gathering skills; very much mimicking the on-going technology driven transformation happening in industry. The VCMs aim to be regularly used in various formats as students progress through their undergraduate degree programme - and we adopt the term `vertical problems' to capture the way models and problem based learning are being utilised, where staff author `sub-plots' that utilise information models in a way that best suits their specific subjects, e.g. cost, time, quality, sustainability subject areas. To this end, the article reports on findings from the research, development and early implementation stages of a programme-wide teaching and learning proposition supported by BIM. This includes a typology that helps target varying degrees of model utilisation and diffusion in given subjects and transitional requirements for both staff and students

Evaluations of BIM: Frameworks and perspectives

© ASCE 2014. This paper examines the evaluation of BIM-enabled projects. It provides a critical review of the three main areas of measurement, namely: technology, organization/people and process. Using two documented case studies of BIM implementation, the paper illustrates the benefits realized by project owners and contractors, and illustrates a lack of attention relative to contextual factors affecting the adoption and deployment of BIM. The paper has three main contributions. First, it identifies and discusses the lack of and difficulty surrounding standardized assessment methods for evaluating BIM-enabled projects. Second, it proposes a conceptual model that includes contextual attributes and demonstrates how the proposed framework reaches beyond simple evaluation to encompass the documentation of BIM's benefits, lessons learned, challenges and adopted solutions. Third, it shows how the framework can account for existing business processes, organizational process assets, and enterprise level factors. The paper aims to provide a conceptual basis for evaluation and a starting point for benchmarking

Comparison of shipbuilding and construction industries from the product structure standpoint

Copyright © 2018 Inderscience Enterprises Ltd. The use of building information modelling (BIM) in construction compares to the use of product lifecycle management (PLM) in manufacturing. Previous research has shown that it is possible to improve BIM with the features and the best practices from the PLM approach. This article provides a comparison from the standpoint of the bill of materials (BOM) and product structures. It compares the product beginning of life in both construction and shipbuilding industries. The research then tries to understand the use, form and evolution of product structures and BOM concepts in shipbuilding with the aim of identifying equivalent notions in construction. Research findings demonstrate that similar concepts for structuring information exist in construction; however, the relationship between them is unclear. Further research is therefore required to detail the links identified by the authors and develop an equivalent central structuring backbone as found in PLM platforms

Prioritising surveillance for alien organisms transported as stowaways on ships travelling to South Africa

The global shipping network facilitates the transportation and introduction of marine and terrestrial organisms to regions where they are not native, and some of these organisms become invasive. South Africa was used as a case study to evaluate the potential for shipping to contribute to the introduction and establishment of marine and terrestrial alien species (i.e. establishment debt) and to assess how this varies across shipping routes and seasons. As a proxy for the number of species introduced (i.e. 'colonisation pressure') shipping movement data were used to determine, for each season, the number of ships that visited South African ports from foreign ports and the number of days travelled between ports. Seasonal marine and terrestrial environmental similarity between South African and foreign ports was then used to estimate the likelihood that introduced species would establish. These data were used to determine the seasonal relative contribution of shipping routes to South Africa's marine and terrestrial establishment debt. Additionally, distribution data were used to identify marine and terrestrial species that are known to be invasive elsewhere and which might be introduced to each South African port through shipping routes that have a high relative contribution to establishment debt. Shipping routes from Asian ports, especially Singapore, have a particularly high relative contribution to South Africa's establishment debt, while among South African ports, Durban has the highest risk of being invaded. There was seasonal variation in the shipping routes that have a high relative contribution to the establishment debt of the South African ports. The presented method provides a simple way to prioritise surveillance effort and our results indicate that, for South Africa, port-specific prevention strategies should be developed, a large portion of the available resources should be allocated to Durban, and seasonal variations and their consequences for prevention strategies should be explored further. (Résumé d'auteur

The Sound Generated by Mid-Ocean Ridge Black Smoker Hydrothermal Vents

Hydrothermal flow through seafloor black smoker vents is typically turbulent and vigorous, with speeds often exceeding 1 m/s. Although theory predicts that these flows will generate sound, the prevailing view has been that black smokers are essentially silent. Here we present the first unambiguous field recordings showing that these vents radiate significant acoustic energy. The sounds contain a broadband component and narrowband tones which are indicative of resonance. The amplitude of the broadband component shows tidal modulation which is indicative of discharge rate variations related to the mechanics of tidal loading. Vent sounds will provide researchers with new ways to study flow through sulfide structures, and may provide some local organisms with behavioral or navigational cues

Epistatic Roles of E2 Glycoprotein Mutations in Adaption of Chikungunya Virus to Aedes Albopictus and Ae. Aegypti Mosquitoes

Between 2005 and 2007 Chikungunya virus (CHIKV) caused its largest outbreak/epidemic in documented history. An unusual feature of this epidemic is the involvement of Ae. albopictus as a principal vector. Previously we have demonstrated that a single mutation E1-A226V significantly changed the ability of the virus to infect and be transmitted by this vector when expressed in the background of well characterized CHIKV strains LR2006 OPY1 and 37997. However, in the current study we demonstrate that introduction of the E1-A226V mutation into the background of an infectious clone derived from the Ag41855 strain (isolated in Uganda in 1982) does not significantly increase infectivity for Ae. albopictus. In order to elucidate the genetic determinants that affect CHIKV sensitivity to the E1-A226V mutation in Ae. albopictus, the genomes of the LR2006 OPY1 and Ag41855 strains were used for construction of chimeric viruses and viruses with a specific combination of point mutations at selected positions. Based upon the midgut infection rates of the derived viruses in Ae. albopictus and Ae. aegypti mosquitoes, a critical role of the mutations at positions E2-60 and E2-211 on vector infection was revealed. The E2-G60D mutation was an important determinant of CHIKV infectivity for both Ae. albopictus and Ae. aegypti, but only moderately modulated the effect of the E1-A226V mutation in Ae. albopictus. However, the effect of the E2-I211T mutation with respect to mosquito infections was much more specific, strongly modifying the effect of the E1-A226V mutation in Ae. albopictus. In contrast, CHIKV infectivity for Ae. aegypti was not influenced by the E2-1211T mutation. The occurrence of the E2-60G and E2-211I residues among CHIKV isolates was analyzed, revealing a high prevalence of E2-211I among strains belonging to the Eastern/Central/South African (ECSA) clade. This suggests that the E2-211I might be important for adaptation of CHIKV to some particular conditions prevalent in areas occupied by ECSA stains. These newly described determinants of CHIKV mosquito infectivity for Ae. albopictus and Ae. aegypti are of particular importance for studies aimed at the investigation of the detailed mechanisms of CHIKV adaptations to its vector species

Probabilistic downscaling of remote sensing data with applications for multi-scale biogeochemical flux modeling

Upscaling ecological information to larger scales in space and downscaling remote sensing observations or model simulations to finer scales remain grand challenges in Earth system science. Downscaling often involves inferring subgrid information from coarse-scale data, and such ill-posed problems are classically addressed using regularization. Here, we apply two-dimensional Tikhonov Regularization (2DTR) to simulate subgrid surface patterns for ecological applications. Specifically, we test the ability of 2DTR to simulate the spatial statistics of high-resolution (4 m) remote sensing observations of the normalized difference vegetation index (NDVI) in a tundra landscape. We find that the 2DTR approach as applied here can capture the major mode of spatial variability of the high-resolution information, but not multiple modes of spatial variability, and that the Lagrange multiplier (γ) used to impose the condition of smoothness across space is related to the range of the experimental semivariogram. We used observed and 2DTR-simulated maps of NDVI to estimate landscape-level leaf area index (LAI) and gross primary productivity (GPP). NDVI maps simulated using a γ value that approximates the range of observed NDVI result in a landscape-level GPP estimate that differs by ca 2% from those created using observed NDVI. Following findings that GPP per unit LAI is lower near vegetation patch edges, we simulated vegetation patch edges using multiple approaches and found that simulated GPP declined by up to 12% as a result. 2DTR can generate random landscapes rapidly and can be applied to disaggregate ecological information and compare of spatial observations against simulated landscapes