http://hdl.handle.net/1842/3521 Wed, 22 May 2013 17:33:47 GMT 2013-05-22T17:33:47Z http://hdl.handle.net/1842/6550 Title: Neural networks for modelling the final target cost of water projects Authors: Ahiaga-Dagbui, Dominic D; Smith, Simon D Abstract: Producing reasonably accurate cost estimates at the planning stage of a project important for the subsequent success of the project. The estimator has to be able to make judgement on the cost influence of a number of factors including site conditions, procurement, risks, price changes, likely scope changes or type of contract. This can shroud the estimation process in uncertainty, which has often resulted in project cost overruns. The knowledge acquisition, generalization and forecasting capabilities of Artificial Neural Networks (ANN) are explored in this pilot study to build final cost estimation models that incorporate the cost effect of some of the factors mentioned above. Data was collected on ninety-eight water-related construction projects completed in Scotland between 2007-2011. Separate cost models were developed for normalized target cost and log of target costs. Variable transformation and weight decay regularization were then explored to improve the final model’s performance. As a prototype of a wider research, the final model’s performance was very satisfactory, demonstrating ANN ability to capture the interactions between the predictor variables and final cost. Ten input variables, all readily available or measurable at the planning stages for the project, were used within a Multilayer Perceptron Architecture and a Quasi-Newton training algorithm. Sat, 01 Sep 2012 00:00:00 GMT http://hdl.handle.net/1842/6550 2012-09-01T00:00:00Z http://hdl.handle.net/1842/5748 Title: Long-term care facilities in Ontario, Canada: A waste management overview Authors: Gales, John; Roy-Poirier, A; Champagne, P Abstract: Long-term care (LTC) facilities are growing in number in the province of Ontario. Typically, Canadian LTC facilities house an average of over 100 residents. Environmental concerns associated to waste management in LTC facilities have not been fully explored, and relevant information is apparently limited in the available research literature. An independent study was conducted to investigate solid waste management in LTC facilities in Ontario. Both privately and municipally-owned LTC facilities were considered. The paper draws its observations from site visits, as well as interviews with facilitators and management of environmental services of LTC facilities. The study explores two main areas of waste management in LTC facilities; characterization of solid waste, and waste disposal criteria. Description: This document represents a public white paper report of three long term facilities studied in 2005. Permission to use the facilities by name was originally obtained though not exercised by the authors. The project began as an independent and self funded study while the lead author was attending the University of Ottawa as an undergraduate student. This project investigated both public and private facilities. Results were compiled in 2009 and presented as a paper at the IASTED International Conference on Environmental Management and Engineering. This paper can be referenced as such. This white paper also includes an additional appendix for calculations made, some grammatical/spelling corrections, new formatting, updated images and the original presentation slides used to relay information at the aforementioned conference. For further details or for the full background documents please send the corresponding author an email. Thu, 01 Jan 2009 00:00:00 GMT http://hdl.handle.net/1842/5748 2009-01-01T00:00:00Z http://hdl.handle.net/1842/5645 Title: Potential Risks to International Joint Ventures In Developing Economies: The Ghanaian Construction Industry Experience Authors: Ahiaga-Dagbui, Dominic D; Fugar, Frank D.K; McCarter, John W; Adinyira, Emmnuel Abstract: International construction companies are increasingly entering into joint ventures with local companies in developing countries to explore perceived profitable opportunities overseas. Joint ventures generally offer a number of benefits but they can become very difficult to manage as a result of many complexities introduced by the association of two or more companies from different countries, with differing political, cultural and legal frameworks, technical and managerial capabilities, and national economic environments. This theoretical study assesses the risks associated with International Construction Joint Ventures in developing economies with particular reference to Ghana. The nature, strengths, weaknesses, opportunities and threats within the Ghanaian construction industry were reviewed. The economy, governance, business environment, infrastructure, resources, etc. of Ghana were also assessed. The main risks factors to International Joint Ventures (IJVs) identified in Ghana can be categorised into two: major risk factors including the microeconomic and financial risk factors and joint venture partner problems. The client’s ability to finance the projects and poor technical, financial and managerial capacities of Ghanaian construction firms were the main factors in this group. The minor risks factors include the availability and high cost of construction materials, issues of bribery and corruption, power supply problems and security. Tue, 01 Nov 2011 00:00:00 GMT http://hdl.handle.net/1842/5645 2011-11-01T00:00:00Z http://hdl.handle.net/1842/5614 Title: Creating FDTD models of commercial GPR antennas using Taguchi’s optimisation method Authors: Warren, Craig; Giannopoulos, Antonios Abstract: Very few researchers have developed numerical models of ground-penetrating radar (GPR) that include realistic descriptions of both the antennas and the subsurface. This is essential to be able to accurately predict responses from near-surface, near-field targets. We have developed a detailed 3D finite-difference time-domain models of two commercial GPR antennas — a Geophysical Survey Systems, Inc. (GSSI) 1.5-GHz antenna and a MALÅ Geoscience 1.2-GHz antenna — using simple analyses of the geometries and the main components of the antennas. Values for unknown parameters in the antenna models (due to commercial sensitivity) were estimated by using Taguchi's optimization method, resulting in a good match between the real and modeled crosstalk responses in free space. Validation using a series of oil-in-water emulsions to simulate the electrical properties of real materials demonstrated that it was essential to accurately model the permittivity and dispersive conductivity. When accurate descriptions of the emulsions were combined with the antenna models, the simulated responses showed very good agreement with real data. This provides confidence for use of the antenna models in more advanced studies. Thu, 17 Mar 2011 00:00:00 GMT http://hdl.handle.net/1842/5614 2011-03-17T00:00:00Z