... AGRICULTURAL DEVELOPMENT TRE Chidley J. Elgy Department of Civil Engineering University of As... more ... AGRICULTURAL DEVELOPMENT TRE Chidley J. Elgy Department of Civil Engineering University of Aston Birmingham, UK and J. Antoine Soil Resources ... the report has benefitted from inputs and comments from R. Brinkman, M. Purnell, F. Nachtergaele and D. Sims in AGLS ...
This paper presented the potential of smart phone to provide support on mapping the indoor asset.... more This paper presented the potential of smart phone to provide support on mapping the indoor asset. The advantage of using the smart phone to generate the indoor map is that it has the ability to capture, store and reproduces still or video images; indeed most of us do have this powerful gadget. The captured images usually used by maintenance team to save a record for future reference. Here, these images are used to generate 3D models of an object precisely and accurately for efficient and effective solution in data gathering. Thus, it could be a resource for an informative database in asset management.
Contractor selection is an important step in ensuring the success of any construction project. Fa... more Contractor selection is an important step in ensuring the success of any construction project. Failing to adequately select the winning contractor may lead to problems in the project delivery phase such as bad quality and delay in the expected project duration; which ultimately results in cost overruns. This paper reviewed the strength of existing studies on the link between contractor selection strategy and project outcomes, with a view of proposing an approach on how one might try to examine this relationship moving forward. There are research that try to establish a direct relationship between contractor selection strategy and the outcome of the construction project. There are also decision support tools such as AHP or ANP that help clients prioritise various factors when selecting contractors. However the majority of these research and tools are informed by self-perception questionnaires and surveys that makes it difficult to gauge the strength of the relationship between contra...
In order to develop sustainable and scientifically defensible environmental strategies, developme... more In order to develop sustainable and scientifically defensible environmental strategies, development planners, regulators, and policy-makers require reliable information relating to the current and future state of the environment, and to the options for minimising levels of pollution and the effects of pollution in a cost-effective way. Techniques for environmental management may be greatly enhanced by combining rigorous administrative protocols with appropriate software tools (based on state-of-the-art data analysis and simulation techniques) to create a "hybrid" environmental management system. This paper describes the AIDAIR R&D project to develop an effects-based air quality management system by the seamless integration of such tools. The software architecture is based on a geographical information system (GIS). Embedded within this structure are a suite of predictive models, and it is backed by a decision support system (DSS), including multi-factorial, multiobjective ...
This study presents a two stage process to determine suitable areas to grow fuel crops: i) FAO Ag... more This study presents a two stage process to determine suitable areas to grow fuel crops: i) FAO Agro Ecological Zones (AEZ) procedure is applied to four Indian states of different geographical characteristics; and ii) Modelling the growth of candidate crops with GEPIC water and nutrient model, which is used to determine potential yield of candidate crops in areas where irrigation water is brackish or soil is saline. Absence of digital soil maps, paucity of readily available climate data and knowledge of detailed requirements of candidate crops are some of the major problems, of which, a series of detailed maps will evaluate true potential of biofuels in India.
Journal of Construction Engineering and Management, 2019
Perceived benefits of the best value strategy and the problems the lowest price strategy has caus... more Perceived benefits of the best value strategy and the problems the lowest price strategy has caused in the construction industry; has led to the increase in the use of the best value strategy in selecting contractors. Whilst there is research that have tried to establish a direct relationship between a contractor selection strategy and the project outcomes, there are hardly any empirical research that tries to establish this relationship. This paper presents a quantifiable method of assessing the risk of selecting different contractor selection strategies using educational facilities projects in the UK. A Monte-Carlo simulation study was conducted to assess how the lowest priced contractor would have fared against the best value contractor had it been awarded the contract instead. It was concluded that selecting the best value contractor in educational facilities projects is not necessary in terms of cost. Furthermore, though the results are limited to educational facilities project, the method can be adapted to other sectors.
25th Annual Conference of the International Group for Lean Construction, 2017
Contractor selection is one of the most important step in ensuring the success of any constructio... more Contractor selection is one of the most important step in ensuring the success of any construction project. Failing to adequately select the winning contractor may lead to problems in the project delivery phase such as bad quality and delay in the expected project duration; which ultimately results in cost overruns. This paper presents an approach by which a what-if scenario can be analysed in educational facilities projects in the UK; therefore if the client selected the best value contractor for a project whose submitted price is not the lowest price, a what-if scenario was conducted to show how the lowest priced contractor would have fared had he/she been awarded the contract instead. This was done by analysing historic data of projects that have selected the lowest priced contractor. Then correlations were derived between variables; which was then be inputted into a Monte Carlo Simulation to analyse 3 real educational facilities projects that used a best value selection method. Using Monte Carlo Simulation allowed us to see all the possible outcomes of cost, and duration. It was concluded that selecting the best value contractor in educational facilities projects may not be necessary in terms of cost.
The issues of linking single process models with GIS have been well rehearsed. Linking several mo... more The issues of linking single process models with GIS have been well rehearsed. Linking several models raises some new issues. Rewriting the logic and relationships of existing models into one large model cannot always be justified. An alternative approach is to construct links from a GIS to the models using a network of programs and structures. Issues of this approach
This work presents a two-dimensional approach of risk assessment method based on the quantificati... more This work presents a two-dimensional approach of risk assessment method based on the quantification of the probability of the occurrence of contaminant source terms, as well as the assessment of the resultant impacts. The risk is calculated using Monte Carlo simulation methods whereby synthetic contaminant source terms were generated to the same distribution as historically occurring pollution events or a priori potential probability distribution. The spatial and temporal distributions of the generated contaminant concentrations at pre-defined monitoring points within the aquifer were then simulated from repeated realisations using integrated mathematical models. The number of times when user defined ranges of concentration magnitudes were exceeded is quantified as risk. The utilities of the method were demonstrated using hypothetical scenarios, and the risk of pollution from a number of sources all occurring by chance together was evaluated. The results are presented in the form of charts and spatial maps. The generated risk maps show the risk of pollution at each observation borehole, as well as the trends within the study area. This capability to generate synthetic pollution events from numerous potential sources of pollution based on historical frequency of their occurrence proved to be a great asset to the method, and a large benefit over the contemporary methods.
Soil erosion is one of the most pressing issues facing developing countries. In Ghana, a country ... more Soil erosion is one of the most pressing issues facing developing countries. In Ghana, a country with an expanding population and high potent ial for economic growth, agriculture is an important resource. The high intens ity seasonal rainfall coincides with the early growing period of crops such as maize, yam and cassava. Agricultural plots are very susceptible to high erosion rates, especially when on steep sided valleys in the region around the south of Lake Volta. Thus, accurate prediction of soil erosion is a necessity. The accuracy of soil erosion models is largely determined by the availability and quality of the sediment yield data used for calibration. A conceptual model based on the CALSITE model is being developed to run in the GRASS GIS package for use in Ghana. The model is being tested on a 14 1cm" basin southwest of Lake Volta, where streamflow, rainfall, soil moisture and sedi ment transport data were collected during September 2000.
The issues of linking single process models with GIS have been well rehearsed. Linking several mo... more The issues of linking single process models with GIS have been well rehearsed. Linking several models raises some new issues. Rewriting the logic and relationships of existing models into one large model cannot always be justified. An alternative approach is to construct links from a GIS to the models using a network of programs and structures. Issues of this approach
A fully three dimensional model of variably saturated flow has been developed to investigate the ... more A fully three dimensional model of variably saturated flow has been developed to investigate the hydrological effects of spatial variability of saturated hydraulic conductivity on a 150 m by 100 m hillslope and assess the validity of the concept of effective hydraulic conductivity. The model is based on the Galerkin approximation to the finite element method. Accessibility to the vector processor of a CDC Cyber 205 supercomputer permitted numerical solutions on grids containing several thousand node points and two thousand time steps. The results suggest that under conditions of predominant subsurface flow the concept of equivalent uniform properties are valid. -Authors
Land cover information suitable for urban drainage modelling is acquired by airborne remote sensi... more Land cover information suitable for urban drainage modelling is acquired by airborne remote sensing. The scanner used is a line scanner that scans continuously while the aircraft¯ies forward recording 11 bands of the electromagnetic spectrum. This is classi®ed by ®rst segmenting the image into approximately homogeneous polygons using a Marr±Hidreth edge detector. These polygons are then classi®ed into roofs, paved areas and permeable land. Rigorous accuracy tests are applied to the classi®ed imagery, which shows that this method gives better results than any of those currently used. Dawn thermal imagery was not used in this study.
This Section applies the theory of the preceding Section to the problems of water supply systems.... more This Section applies the theory of the preceding Section to the problems of water supply systems. The first section looks at the use of GIS with environmental process models. The second section covers the use of GIS and remote sensing techniques in demand evaluation and forecasting. The third section looks at two current applications of remote sensing for water supplies; the detection of buried objects and leaks, and the assessment of water quality. The last section considers the issues of using GIS and remote sensing in a utilities environment.
... AGRICULTURAL DEVELOPMENT TRE Chidley J. Elgy Department of Civil Engineering University of As... more ... AGRICULTURAL DEVELOPMENT TRE Chidley J. Elgy Department of Civil Engineering University of Aston Birmingham, UK and J. Antoine Soil Resources ... the report has benefitted from inputs and comments from R. Brinkman, M. Purnell, F. Nachtergaele and D. Sims in AGLS ...
This paper presented the potential of smart phone to provide support on mapping the indoor asset.... more This paper presented the potential of smart phone to provide support on mapping the indoor asset. The advantage of using the smart phone to generate the indoor map is that it has the ability to capture, store and reproduces still or video images; indeed most of us do have this powerful gadget. The captured images usually used by maintenance team to save a record for future reference. Here, these images are used to generate 3D models of an object precisely and accurately for efficient and effective solution in data gathering. Thus, it could be a resource for an informative database in asset management.
Contractor selection is an important step in ensuring the success of any construction project. Fa... more Contractor selection is an important step in ensuring the success of any construction project. Failing to adequately select the winning contractor may lead to problems in the project delivery phase such as bad quality and delay in the expected project duration; which ultimately results in cost overruns. This paper reviewed the strength of existing studies on the link between contractor selection strategy and project outcomes, with a view of proposing an approach on how one might try to examine this relationship moving forward. There are research that try to establish a direct relationship between contractor selection strategy and the outcome of the construction project. There are also decision support tools such as AHP or ANP that help clients prioritise various factors when selecting contractors. However the majority of these research and tools are informed by self-perception questionnaires and surveys that makes it difficult to gauge the strength of the relationship between contra...
In order to develop sustainable and scientifically defensible environmental strategies, developme... more In order to develop sustainable and scientifically defensible environmental strategies, development planners, regulators, and policy-makers require reliable information relating to the current and future state of the environment, and to the options for minimising levels of pollution and the effects of pollution in a cost-effective way. Techniques for environmental management may be greatly enhanced by combining rigorous administrative protocols with appropriate software tools (based on state-of-the-art data analysis and simulation techniques) to create a "hybrid" environmental management system. This paper describes the AIDAIR R&D project to develop an effects-based air quality management system by the seamless integration of such tools. The software architecture is based on a geographical information system (GIS). Embedded within this structure are a suite of predictive models, and it is backed by a decision support system (DSS), including multi-factorial, multiobjective ...
This study presents a two stage process to determine suitable areas to grow fuel crops: i) FAO Ag... more This study presents a two stage process to determine suitable areas to grow fuel crops: i) FAO Agro Ecological Zones (AEZ) procedure is applied to four Indian states of different geographical characteristics; and ii) Modelling the growth of candidate crops with GEPIC water and nutrient model, which is used to determine potential yield of candidate crops in areas where irrigation water is brackish or soil is saline. Absence of digital soil maps, paucity of readily available climate data and knowledge of detailed requirements of candidate crops are some of the major problems, of which, a series of detailed maps will evaluate true potential of biofuels in India.
Journal of Construction Engineering and Management, 2019
Perceived benefits of the best value strategy and the problems the lowest price strategy has caus... more Perceived benefits of the best value strategy and the problems the lowest price strategy has caused in the construction industry; has led to the increase in the use of the best value strategy in selecting contractors. Whilst there is research that have tried to establish a direct relationship between a contractor selection strategy and the project outcomes, there are hardly any empirical research that tries to establish this relationship. This paper presents a quantifiable method of assessing the risk of selecting different contractor selection strategies using educational facilities projects in the UK. A Monte-Carlo simulation study was conducted to assess how the lowest priced contractor would have fared against the best value contractor had it been awarded the contract instead. It was concluded that selecting the best value contractor in educational facilities projects is not necessary in terms of cost. Furthermore, though the results are limited to educational facilities project, the method can be adapted to other sectors.
25th Annual Conference of the International Group for Lean Construction, 2017
Contractor selection is one of the most important step in ensuring the success of any constructio... more Contractor selection is one of the most important step in ensuring the success of any construction project. Failing to adequately select the winning contractor may lead to problems in the project delivery phase such as bad quality and delay in the expected project duration; which ultimately results in cost overruns. This paper presents an approach by which a what-if scenario can be analysed in educational facilities projects in the UK; therefore if the client selected the best value contractor for a project whose submitted price is not the lowest price, a what-if scenario was conducted to show how the lowest priced contractor would have fared had he/she been awarded the contract instead. This was done by analysing historic data of projects that have selected the lowest priced contractor. Then correlations were derived between variables; which was then be inputted into a Monte Carlo Simulation to analyse 3 real educational facilities projects that used a best value selection method. Using Monte Carlo Simulation allowed us to see all the possible outcomes of cost, and duration. It was concluded that selecting the best value contractor in educational facilities projects may not be necessary in terms of cost.
The issues of linking single process models with GIS have been well rehearsed. Linking several mo... more The issues of linking single process models with GIS have been well rehearsed. Linking several models raises some new issues. Rewriting the logic and relationships of existing models into one large model cannot always be justified. An alternative approach is to construct links from a GIS to the models using a network of programs and structures. Issues of this approach
This work presents a two-dimensional approach of risk assessment method based on the quantificati... more This work presents a two-dimensional approach of risk assessment method based on the quantification of the probability of the occurrence of contaminant source terms, as well as the assessment of the resultant impacts. The risk is calculated using Monte Carlo simulation methods whereby synthetic contaminant source terms were generated to the same distribution as historically occurring pollution events or a priori potential probability distribution. The spatial and temporal distributions of the generated contaminant concentrations at pre-defined monitoring points within the aquifer were then simulated from repeated realisations using integrated mathematical models. The number of times when user defined ranges of concentration magnitudes were exceeded is quantified as risk. The utilities of the method were demonstrated using hypothetical scenarios, and the risk of pollution from a number of sources all occurring by chance together was evaluated. The results are presented in the form of charts and spatial maps. The generated risk maps show the risk of pollution at each observation borehole, as well as the trends within the study area. This capability to generate synthetic pollution events from numerous potential sources of pollution based on historical frequency of their occurrence proved to be a great asset to the method, and a large benefit over the contemporary methods.
Soil erosion is one of the most pressing issues facing developing countries. In Ghana, a country ... more Soil erosion is one of the most pressing issues facing developing countries. In Ghana, a country with an expanding population and high potent ial for economic growth, agriculture is an important resource. The high intens ity seasonal rainfall coincides with the early growing period of crops such as maize, yam and cassava. Agricultural plots are very susceptible to high erosion rates, especially when on steep sided valleys in the region around the south of Lake Volta. Thus, accurate prediction of soil erosion is a necessity. The accuracy of soil erosion models is largely determined by the availability and quality of the sediment yield data used for calibration. A conceptual model based on the CALSITE model is being developed to run in the GRASS GIS package for use in Ghana. The model is being tested on a 14 1cm" basin southwest of Lake Volta, where streamflow, rainfall, soil moisture and sedi ment transport data were collected during September 2000.
The issues of linking single process models with GIS have been well rehearsed. Linking several mo... more The issues of linking single process models with GIS have been well rehearsed. Linking several models raises some new issues. Rewriting the logic and relationships of existing models into one large model cannot always be justified. An alternative approach is to construct links from a GIS to the models using a network of programs and structures. Issues of this approach
A fully three dimensional model of variably saturated flow has been developed to investigate the ... more A fully three dimensional model of variably saturated flow has been developed to investigate the hydrological effects of spatial variability of saturated hydraulic conductivity on a 150 m by 100 m hillslope and assess the validity of the concept of effective hydraulic conductivity. The model is based on the Galerkin approximation to the finite element method. Accessibility to the vector processor of a CDC Cyber 205 supercomputer permitted numerical solutions on grids containing several thousand node points and two thousand time steps. The results suggest that under conditions of predominant subsurface flow the concept of equivalent uniform properties are valid. -Authors
Land cover information suitable for urban drainage modelling is acquired by airborne remote sensi... more Land cover information suitable for urban drainage modelling is acquired by airborne remote sensing. The scanner used is a line scanner that scans continuously while the aircraft¯ies forward recording 11 bands of the electromagnetic spectrum. This is classi®ed by ®rst segmenting the image into approximately homogeneous polygons using a Marr±Hidreth edge detector. These polygons are then classi®ed into roofs, paved areas and permeable land. Rigorous accuracy tests are applied to the classi®ed imagery, which shows that this method gives better results than any of those currently used. Dawn thermal imagery was not used in this study.
This Section applies the theory of the preceding Section to the problems of water supply systems.... more This Section applies the theory of the preceding Section to the problems of water supply systems. The first section looks at the use of GIS with environmental process models. The second section covers the use of GIS and remote sensing techniques in demand evaluation and forecasting. The third section looks at two current applications of remote sensing for water supplies; the detection of buried objects and leaks, and the assessment of water quality. The last section considers the issues of using GIS and remote sensing in a utilities environment.
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