Shabtai Isaac - Academia.edu (original) (raw)
Papers by Shabtai Isaac
Journal of Construction Engineering and Management
Construction Management and Economics, 2013
An extended research programme has examined over the past two decades how productivity in constru... more An extended research programme has examined over the past two decades how productivity in construction projects can be improved through the development of models for project monitoring and control, which process automatically collected data on the actual project performance. Tests that were conducted with these models demonstrate that this approach can help overcome some of the limitations of existing manual methods. However, they also indicate that certain manually obtained data are still required in addition to the automatically collected data. A framework for semi-automated project monitoring and control is proposed, in which both manually and automatically collected data can be incorporated. This framework integrates the monitoring of projects with their control by taking into account the impact on productivity of existing deviations from the planned performance, and of the controlling actions that are proposed to deal with these deviations.
Frontiers in Built Environment
Journal of Cleaner Production
Automation in Construction
Sustainability
The objective of this research is to study the cost of Net Zero Energy (NZE) communities of diffe... more The objective of this research is to study the cost of Net Zero Energy (NZE) communities of different urban scales and densities, while taking into consideration the local climate and the type of buildings in the community. A comprehensive model was developed for this purpose, with which the cost-optimal configuration of renewable energy-related technologies for an NZE community can be identified. To validate the model, data from two case studies that differed in their climate and building types were used. The results of this study contribute to a better understanding of the implications of NZE requirements for urban planning. An increase in the scale of a community was found to reduce energy costs, up to a certain point. Urban density, on the other hand, was found to have a more complex impact on costs, which depends on the local climate of the community and the subsequent energy demand. This underlines the importance of addressing the technological design of energy systems at the ...
IOP Conference Series: Earth and Environmental Science
Journal of Construction Engineering and Management
Proceedings of the 35th International Symposium on Automation and Robotics in Construction (ISARC)
Efforts to integrate construction planning have thus far focused on the interoperability of model... more Efforts to integrate construction planning have thus far focused on the interoperability of models and computer applications. However, merely linking different models, e.g. design and schedule, while useful, necessarily restricts planners to an iterative improvement of plans. This research defines a single integrated mathematical model with singularity functions to directly represent the different aspects that need to be considered in planning construction projects, such as their design, schedule, budget, site layout, etc. This allows all relevant aspects to be taken into account simultaneously when optimizing the construction plan. The new model can be used to visualize different aspects of a project, allowing the planner to interact with the model and manipulate it. Examples are provided for the intuitive visualization of the time-space that building components, site objects and construction activities occupy, of the dynamic relations and buffers between objects and activities, and of the impact of changes in the plan.
Proceedings of the 35th International Symposium on Automation and Robotics in Construction (ISARC)
Construction management courses are currently mostly based on frontal lectures, homework and exam... more Construction management courses are currently mostly based on frontal lectures, homework and examswhere the exams comprise of questions similar to the ones that the professor showed in the lectures & later the student is asked to solve at home. In practice, construction engineers are required to be able to quickly resolve unstructured complex problems, under conditions of uncertainty, by finding, collecting and integrating information from different sources and providing creative solutions. We propose that a learning-centered approach to the education of the construction management student, in which s/he is confronted with the need to find solutions for such complex problems, and to identify the relevant data, will better prepare the future engineer for the profession. Moreover, the students have to be exposed to the fact that there is more than one correct solution and none of the solutions is perfect. Ethical dilemmas in particular may require construction managers to resolve problems for which they cannot rely on simple formulas. An elective course in construction management, which has been developed over the past four years, in which these principles have been incorporated, will be described.
Automation in Construction
Journal of Computing in Civil Engineering
Environmental management, May 1, 2017
This study seeks to attain a better understanding of the information that is required by governme... more This study seeks to attain a better understanding of the information that is required by governments to prepare for earthquakes, and of the constraints they face in obtaining this information. The contributions of the study are two-fold. A survey that was conducted among those responsible for earthquake preparedness actions in different governmental agencies and at different levels revealed on the one hand a desire for information on a broad range of topics, but on the other hand that no resources were allocated in practice to gather this information. A Geographic Information System-based process that was developed following the survey, allowed the required information on seismic hazards and loss and damage risks to be rapidly collected, mapped and integrated. This supported the identification of high-priority areas, for which a more detailed analysis could be initiated. An implementation of the process showed promise, and confirmed its feasibility. Its relative simplicity may ensur...
Journal of Civil Engineering and Management, 2016
A statistical safety control method is presented that utilizes location data from a relatively in... more A statistical safety control method is presented that utilizes location data from a relatively inaccurate yet cost-effective system to track workers in real time, and prevent unsafe situations at construction sites. In light of the inaccuracy of the tracking system, buffer areas are defined as statistical zones, at some distance from potential workplace hazards. Statistical alerts are created according to predefined rules when the hazard exposure of workers in those zones crosses a certain threshold. The results of tests of the method demonstrate that the model is able to successfully process the location data in order to compensate for its inaccuracy. This is done without necessitating a significant increase in the areas that are defined as being of high risk, and therefore off-limits for most workers on site. The model can thus ensure the efficiency of the construction work by restricting the size of the areas on site that are off-limits for most workers, while at the same time ...
Annals of Operations Research, 2016
Automation in Construction, 2016
Automation in Construction, 2016
Journal of Construction Engineering and Management
Construction Management and Economics, 2013
An extended research programme has examined over the past two decades how productivity in constru... more An extended research programme has examined over the past two decades how productivity in construction projects can be improved through the development of models for project monitoring and control, which process automatically collected data on the actual project performance. Tests that were conducted with these models demonstrate that this approach can help overcome some of the limitations of existing manual methods. However, they also indicate that certain manually obtained data are still required in addition to the automatically collected data. A framework for semi-automated project monitoring and control is proposed, in which both manually and automatically collected data can be incorporated. This framework integrates the monitoring of projects with their control by taking into account the impact on productivity of existing deviations from the planned performance, and of the controlling actions that are proposed to deal with these deviations.
Frontiers in Built Environment
Journal of Cleaner Production
Automation in Construction
Sustainability
The objective of this research is to study the cost of Net Zero Energy (NZE) communities of diffe... more The objective of this research is to study the cost of Net Zero Energy (NZE) communities of different urban scales and densities, while taking into consideration the local climate and the type of buildings in the community. A comprehensive model was developed for this purpose, with which the cost-optimal configuration of renewable energy-related technologies for an NZE community can be identified. To validate the model, data from two case studies that differed in their climate and building types were used. The results of this study contribute to a better understanding of the implications of NZE requirements for urban planning. An increase in the scale of a community was found to reduce energy costs, up to a certain point. Urban density, on the other hand, was found to have a more complex impact on costs, which depends on the local climate of the community and the subsequent energy demand. This underlines the importance of addressing the technological design of energy systems at the ...
IOP Conference Series: Earth and Environmental Science
Journal of Construction Engineering and Management
Proceedings of the 35th International Symposium on Automation and Robotics in Construction (ISARC)
Efforts to integrate construction planning have thus far focused on the interoperability of model... more Efforts to integrate construction planning have thus far focused on the interoperability of models and computer applications. However, merely linking different models, e.g. design and schedule, while useful, necessarily restricts planners to an iterative improvement of plans. This research defines a single integrated mathematical model with singularity functions to directly represent the different aspects that need to be considered in planning construction projects, such as their design, schedule, budget, site layout, etc. This allows all relevant aspects to be taken into account simultaneously when optimizing the construction plan. The new model can be used to visualize different aspects of a project, allowing the planner to interact with the model and manipulate it. Examples are provided for the intuitive visualization of the time-space that building components, site objects and construction activities occupy, of the dynamic relations and buffers between objects and activities, and of the impact of changes in the plan.
Proceedings of the 35th International Symposium on Automation and Robotics in Construction (ISARC)
Construction management courses are currently mostly based on frontal lectures, homework and exam... more Construction management courses are currently mostly based on frontal lectures, homework and examswhere the exams comprise of questions similar to the ones that the professor showed in the lectures & later the student is asked to solve at home. In practice, construction engineers are required to be able to quickly resolve unstructured complex problems, under conditions of uncertainty, by finding, collecting and integrating information from different sources and providing creative solutions. We propose that a learning-centered approach to the education of the construction management student, in which s/he is confronted with the need to find solutions for such complex problems, and to identify the relevant data, will better prepare the future engineer for the profession. Moreover, the students have to be exposed to the fact that there is more than one correct solution and none of the solutions is perfect. Ethical dilemmas in particular may require construction managers to resolve problems for which they cannot rely on simple formulas. An elective course in construction management, which has been developed over the past four years, in which these principles have been incorporated, will be described.
Automation in Construction
Journal of Computing in Civil Engineering
Environmental management, May 1, 2017
This study seeks to attain a better understanding of the information that is required by governme... more This study seeks to attain a better understanding of the information that is required by governments to prepare for earthquakes, and of the constraints they face in obtaining this information. The contributions of the study are two-fold. A survey that was conducted among those responsible for earthquake preparedness actions in different governmental agencies and at different levels revealed on the one hand a desire for information on a broad range of topics, but on the other hand that no resources were allocated in practice to gather this information. A Geographic Information System-based process that was developed following the survey, allowed the required information on seismic hazards and loss and damage risks to be rapidly collected, mapped and integrated. This supported the identification of high-priority areas, for which a more detailed analysis could be initiated. An implementation of the process showed promise, and confirmed its feasibility. Its relative simplicity may ensur...
Journal of Civil Engineering and Management, 2016
A statistical safety control method is presented that utilizes location data from a relatively in... more A statistical safety control method is presented that utilizes location data from a relatively inaccurate yet cost-effective system to track workers in real time, and prevent unsafe situations at construction sites. In light of the inaccuracy of the tracking system, buffer areas are defined as statistical zones, at some distance from potential workplace hazards. Statistical alerts are created according to predefined rules when the hazard exposure of workers in those zones crosses a certain threshold. The results of tests of the method demonstrate that the model is able to successfully process the location data in order to compensate for its inaccuracy. This is done without necessitating a significant increase in the areas that are defined as being of high risk, and therefore off-limits for most workers on site. The model can thus ensure the efficiency of the construction work by restricting the size of the areas on site that are off-limits for most workers, while at the same time ...
Annals of Operations Research, 2016
Automation in Construction, 2016
Automation in Construction, 2016