WSC 2009 Final Abstracts

Location-Based Management of Construction Projects: Part of a New Typology for Project Scheduling Methodologies
Russell Kenley (Swinburne University of Technology) and Olli Seppänen (Vico Software)

Abstract:
The domain of project scheduling has various disparate techniques, each competing to be the best for effective planning and control of projects. Especially, there are many terms for the family of construction scheduling methods which variously involve repetition, linear relationships, vertical or horizontal staging or in some other way map production units against time. This paper considers the underlying rationale behind those terms and proposes a new typology to encapsulate the entire family of scheduling methods and specifically to differentiate the family of production-oriented methodologies from the more common critical path methodologies. The following are proposed: activity-based methodologies which may be divided into deterministic and probabilistic, and location-based methodologies which may be divided into unit production and location production. The paper then shows how location production in the location-based methodology involves focusing on locations as the unit of analysis and tasks as the unit of control for effective production management.

Resource Leveling of Linear Schedules with Singularity Functions
Gunnar Lucko and Angel A. Peña Orozco (Catholic University of America)

Abstract:
This paper builds on a new methodology of modeling linear schedules with singularity functions. These unique functions have been used successfully for criticality and float analyses. The approach is extended to deriving one flexible equation for the complete resource profile of a schedule, including any changes in the resource rates of activities. A subsequent equation describes the first moment of area of the resource profile. Minimizing the moment is the objective function for leveling the resource profile. A genetic algorithm with inverse ranking is computerized to perform successive iterations. Chromosomes contain different permutations resource rates at which the activities can be performed. Probabilistic reproduction, crossover, and mutation steps mimic a biological selection process. Step-by-step descriptions of the calculations and a detailed example of a construction project illustrate how singularity functions can provide a powerful model that integrates the linear schedule with its resource profile and facilitates the overall optimization process.

A Hierarchical Constraint-Based Approach to Modeling Construction and Manufacturing Processes
Ian Flood (University of Florida)

Abstract:
Modeling construction processes is an essential part of project planning and control. Most modeling exercises use the Critical Path Method (CPM) since it is simple to use and versatile. Almost all other modeling techniques are aimed at specialized types of construction work, such as linear scheduling which is used for modeling work that progresses along a line. Discrete-Event simulation has also been used for construction modeling, and while it is extremely versatile, it lacks the simplicity in use of CPM and so has not been widely adopted within the industry. This paper goes back to first principles, identifying the needs of construction project planning and how existing tools meet (or fail to meet) these requirements. Based on this, a new modeling paradigm is proposed that is better suited to the needs of contemporary construction project planning. The principles of the method are demonstrated in application to three example construction projects.

Simulation-Optimization Integrated Approach to Planning Ready Mixed Concrete Production and Delivery: Validation and Applications
Ming Lu and Hoi-Ching Lam (Hong Kong Polytechnic University)

Abstract:
Powered by the simulation and optimization engines resulting from recent research, a computer system named HKCONSIM is ready to provide concrete plant managers with decision support in making the best operation strategy for delivering concrete to multiple site clients. A case study describing one-day operations of the batch plant is used to illustrate the decision support functions HKCONSIM can provide. The case study consists of four parts: (1) input data preparation, (2) the definitions of relevant measures of the system performance, (3) simulation model validation by comparing the simulation outputs against the actual records, and (4) further optimization analysis under three "what-if" scenarios postulated with practical implications. In conclusion, the batch plant operators can draw on HKCONSIM to augment their experiences, corroborate their intuitions, and create new intelligence in coping challenges in day-by-day operations planning.

Sustainability Analysis of Earthmoving Operations
Changbum Ahn (University of Illinois at Urbana-Champaign), Prasant Rekapalli and Julio Martinez (Purdue University) and Feniosky Peña-Mora (Columbia University)

Abstract:
Emissions from construction equipment are the main contributor of environmental impacts from construction processes, and mitigating these impacts is an important aspect of operations design and planning. To this end, emission estimation models play an important role in environmental management of construction operations. This paper presents an emission model that integrates with discrete-event simulation (DES) for more accurate emission estimates from construction operations compared to existing models. The paper also presents a case study which analyzes sustainability of an earthmoving operation, to dem-onstrate the application of DES for estimating emissions.

Using Simulation Analysis for Mining Project Risk Management
Undram Chinbat and Soemon Takakuwa (Nagoya University)

Abstract:
As a result of the current economic crisis, which led to metal prices fall, mining company managers have been encouraged to cut costs. Thus, improvement projects to reduce cost has become major interest in the Mongolian mining industry. Mining projects are subject to high risk because of their size, uncertainty, complexity and high cost. This paper focuses on the development of a simulation method which provides an engineering tool for managing risks associated with the development of open mining improvement projects. The study will demonstrate the advantages of using simulation analysis for mining project management and how it reduces associated risks. The research was based on a case study of an optimization project of a mining plant based in Mongolia.

An Overview of the COSYE Environment for Construction Simulation
Simaan M. AbouRizk and Stephen Hague (University of Alberta)

Abstract:
As the degree of complexity in construction systems increases, the concepts of construction simulation must be advanced and formalized in practice as the primary means for designing, analyzing, planning, and controlling construction projects and facilities. Whereas the prevalent approach for simulating construction operations has traditionally been discrete-event process interaction simulation, the authors propose a strategic re-engineering of simulation methods in dynamic Construction Synthetic Environments (COSYE). The High Level Architecture (HLA) is identified as one of the most promising approaches to address the challenges faced by construction simulation and decision support. This architecture has been adopted as the basis of a new generation of modeling and simulation tools. In this paper, the authors propose a model for developing virtual environments to capture all features, resources and processes required to design, build, and maintain a facility, outlining the COSYE environment and federation structure, and describing a test application in construction bidding simulation.

Real Options and System Dynamics Approach to Model Value of Implementing a Project Specific Dispute Resolution Process in Construction Projects
Carol C. Menassa (University of Wisconsin - Madison)

Abstract:
This paper presents a methodology to study the effect of different resolution strategies on the value of the investment in a project-specific dispute resolution ladder (DRL) using option/real option theories from financial engineering, process centric modeling, and system dynamics methodology. Of particular interest in this paper is the integration of these research methodologies into a computer model to support the evaluation of the DRL investment in a particular construction project by taking into account the characteristics of: (1) the project, and (2) the different alternative dispute resolution (ADR) techniques chosen for the DRL implementation. Finally, an example is presented to illustrate the application of the computer model in a real construction project.

Meaningful Level of Change in Hybrid Simulation for Construction Analysis
Amin Alvanchi, SangHyun Lee, and Simaan AbouRizk (University of Alberta)

Abstract:
Hybrid models of System Dynamics (SD) and Discrete Event Simulation (DES) in the construction industry aim to provide decision makers with more accurate analysis. However, there are certain issues that can limit the applicability of SD-DES hybrid models for real construction job situations. Meaningful Level of Change (MLC) is a concept that has been proposed to prevent the time advancing issue in the hybrid models used within the construction domain. It is claimed that by utilizing the MLC, the running time of hybrid simulation models can be reduced while only slightly contributing to model inaccuracy. In this paper, we investigate the effects of utilizing the MLC for SD-DES hybrid models used for construction systems. First, the theoretical aspects of applying the MLC in hybrid models are investigated. Second, the effects of using different set values of MLC in an experimental model of a real construction system are illustrated.

Development of a Visual Whole Life-cycle Energy Assesment Framework for Built Environment
Saad Dawood, Richard Lord, and Nashwan Dawood (Teesside University)

Abstract:
The UNFCC (United Nations Framework Convention on Climate Change) adopted the Kyoto protocol, establishing legally binding targets for the developed world countries that ratified the protocol. It aims to reduce greenhouse gas emissions by an overall 5% below 1990 levels during the period between 2008 and 2012. Our review of current literature and research projects in the area of sustainability, energy and assessment applied to Built Environment identified gaps in current knowledge and tools. There is also a need to integrate sustainability within the whole life cycle (WLC) of a building from design through construction to operation. This paper aims to give an overall review of the knowledge and technologies in the research area. We present a framework, methodologies and technologies that will facilitate the integration of Environmental Impact Assessment (EIA), Whole Life Cycle Cost Assessment (WLCCA) and Life Cycle Assessment (LCA) using 3D and BIM technologies.

Use of Building Information Models in Simulations
Raja R. A. Issa (University of Florida), Patrick Suermann (US Air Force) and Svetlana Olbina (University of Florida)

Abstract:
The transition to Building Information Modeling (BIM) represents a substantial shift from existing business practices in the architecture, engineering, construction, and facility operations (AECO) arena. While the move from drafting to computer aided design (CAD) sought to automate an existing business practice, successful BIM virtually builds a structure first. Similar to the virtual prototypes in the manufacturing industry, now AECO designers and maintainers can use these virtual models for evaluating various courses of action for improved design and construction. This is especially true in the area of sustainability analysis for design factors such as day-lighting, climate control, and energy usage. This paper will address new emerging business processes stemming from BIM simulations.

Ensuring Building Performance Through Simulation
Dana K. Smith (National Institute of Building Sciences)

Abstract:
The complexities of multi-faceted decision-making are presented which identify opportunities for the use of a mature building information model in the simulation of a facility, not only during design and construction but also throughout its life to include after handoff to the owner and occupant. Having the authoritative source provide design and functional information allows the occupant to understand how the facility will function prior to construction and better understand the cost of operations on an annual basis for the life of the facility. Life cycle based simulation of facilities using building information models will provide the predictive information necessary to do a profoundly better job of operating a facility because you can work according to a plan defined prior to construction.

Using Virtual Environments to Support Electrical Safety Awareness in Construction
Dong Zhao, Jason David Lucas, and Walid Thabet (Virginia Tech)

Abstract:
Safety is important to the construction industry. Every year lives are lost due to accidents that could have been prevented with proper training and awareness of workplace hazards. Electrical safety hazards are the cause of about a quarter of all deaths within the construction industry. Enhanced training methods that are active and interactive can augment electrical safety training for all construction workers and reduce accidents and fatalities caused by electrical shock. Virtual Environment (VE’s) simulations have been used with success for safety training within the construction industry. VE simulation offers an active form of training that allows the user to interact with a modeled environment. This active training allows for a development of cognitive abilities and awareness that typically improve the users’ comprehension of training material. This paper discusses issues concerning electrical safety within the construction industry. It then discusses the benefits of using an active training approach such as VE simulation and its effects on the cognitive abilities of users. Lastly, a proposed safety training program is discussed that can help augment electrical safety training practices in the construction industry. Within the proposed safety training program a VE simulation prototype is planned. The initial development of the prototype simulation is also presented.

Analytical Approach to Augmenting Site Photos with 3D As-Built Bored Pile Models
Fei Dai and Ming Lu (Hong Kong Polytechnic University)

Abstract:
To acquire information of the invisible underground infrastructure, non-destructive subsurface imaging technologies are generally utilized. In construction, the recorded data of as-built pile excavation is solely archived on the Koden test result sheet. The result is in the form of literal document and identified by the pile numbering. The graphical presentation of the result may provide a clearer and easier way for engineers to investigate the pile alignment by merging the result onto the real site photo. The key is to devise a "virtual camera" to project the three-dimensional as-built model of the bored pile onto a two-dimensional view of the site scene, resulting in an augmented photo of the bored pile. The mathematical equations are formulated to allow for parameterization of the projection. A case of augmenting a ground site photo with as-built underground data for the purpose of investigation of alignment for a bored pile construction is demonstrated.

An Experimental Framework to Analyze Alternative Decision-making Strategies Using Situational Simulations in Construction Management
Amlan Mukherjee, Nilufer Onder, Corey A. Tebo, and Kekoa Kaaikala (Michigan Technological University)

Abstract:
Situational simulations are dynamic, interactive, context-sensitive, adaptive environments. They further construction research by providing an interactive simulation platform that can be used to explore what-if construction scenarios and to estimate risks and contingencies. This paper extends current research to study the evolution of dynamic uncertainty in construction management projects using situational simulations as experimental testbeds. An experimental framework is proposed to explore alternative outcomes of a particular decision strategy, and also investigate the impact of alternative decision strategies under similar project scenarios. A set of preliminary experiments were conducted to illustrate the proposed framework. The significance of this research is in enhancing and informing the deliberative process during the planning and pre-planning stages of a construction project and supporting the preparation of contingency plans of action in anticipation of varying levels of project risk and uncertainty.

Simulating the Effect of Learning Decay on Adaptation Performance in Project Networks
Jiayu Chen, John E. Taylor, and Hakan I. Unsal (Columbia University)

Abstract:
In this paper we extend a multi-agent simulation model for interorganizational learning to explore the issue of learning decay on adaptation performance. Researchers agree that project networks can support the development and exchange of new knowledge among firms, however, the question of learning beyond the firm at the boundaries between firms or at the level of the network remains less explored. Previous research has shown that relational instability in networks can slow learning and that task interdependence moderates the impact of increasing relational instability on project network adaptation performance. Research to date on this phenomenon neglects the effect of forgetting which may impact the performance of project networks where firms work together infrequently. We find these gaps in time between learning events can negatively impact the adaptation rate of relationally unstable project networks. These findings are critical to developing a comprehensive understanding of learning in interorganizational project networks.

Simulation of Project-Based Organizational Design in China: From the Perspective of Contexual Interactions
Huanhuan Wang, Bin Hu, and Guoyin Jiang (Sch. of Management,Huazhong University of Sci. and Tech.)

Abstract:
The project-based organizations engaging in engineering consultancy are at the early stage in China. For the manager of China, how to conduct the organization design for them according to contextuality that characterizes the conditions of China is an important issue. First, the factors that affect the performance of this type of the project-based organization of China are analyzed. Then, the organizational design model that has both the advantages of NK model and the ones of complementarity framework is proposed. The impacts of the interactions among the design dimensions of organization, capability to gain resource and turbulence of the environment on the organizational design are researched with simulation approach. Furthermore, the qualitative demonstration of the model is done with data and materials gathered from the actual cases. Last, the implications of the results are put forward.

Rapid Deployment of Simulation Models for Building Construction Applications
Gunnar Lucko (Catholic University of America), Kannan Swaminathan and Perakath C. Benjamin (Knowledge Based Systems, Inc.) and Michael G. Madden (M. Madden Consulting, LLC)

Abstract:
This paper presents a knowledge based approach to increase the use of simulation in the construction industry without its users having to become or hire experts in simulation techniques. The premise of this approach is to use existing process-related schedule information as inputs to create a functioning simulation model with little or no user intervention. It explains analytical capabilities and limitations of schedules and simulation, reviews previous discrete event simulation studies, and discusses integrating knowledge from this domain. It describes the architecture of the WorkSim system. A case study presents processes of a real construction project. The conceptual and pragmatic feasibility of converting schedules into simulations is tested with its representative sample dataset. Modeling and analyzing this case study establishes the technical viability of the ideas discussed in the paper. Future work will examine challenges to the quality of such models, e.g. their resolution, required resource data, and duration distributions.

Proposed Methodology for Comparing Schedule Generation Schemes in Construction Resource Scheduling
Jin-Lee Kim (California State University, Long Beach)

Abstract:
This paper proposes a methodology to compare the serial scheme with the parallel scheme in a decoding procedure of permutation-based genetic algorithm for construction resource scheduling. Elitist genetic algorithm based on the serial scheme, which was previously developed by the author, is used as a platform to integrate the parallel scheme. Since two schedule generation schemes have different mechanisms, it is meaningful to demonstrate the effects of the scheme on the performance of an algorithm. The ultimate goal of this study is to address the issue with regard to which of the schedule generation schemes will perform better for an arbitrary instance of resource scheduling problems. Thirty problems are solved here to compare their project durations according to the scheme. Scheduling results indicate that Elitist genetic algorithm using the serial scheme provides better solutions than the one using the parallel scheme.

Generating Simulation Network for Design Process Based on Dsm
Md. Aslam Hossain and David Kim Huat Chua (National University of Singapore)

Abstract:
Use of simulation technique is becoming more popular in managing design process. However, developing a simulation model can be very tedious and knowledge demanding, and a simulation model developed for one project cannot readily be used for others due to the unique nature of design project. This paper develops a generalized simulation model for the design process which is capable of generating simulation network automatically for any design project based on dependency relationships as represented by DSM. Concept of estimability and rework of design activities has been utilized in reducing the overall design completion time. Simulation can be run for the generated network to get a probabilistic design schedule. The proposed concept of autogeneration of simulation network has been studied with a case study. It is very efficient in generating the simulation network for any design process and saves the tedious job of simulation model development.

Applications of Discrete-Event Simulation to Reliability and Availability Assessment in Civil Engineering Structures
Angel A. Juan (Open University of Catalonia), Arai Monteforte (ReliaSoft Inc.), Albert Ferrer and Carles Serrat (Technical University of Catalonia) and Javier Faulin (Public University of Navarre)

Abstract:
This paper discusses the convenience of predicting, quantitatively, time-dependent reliability and availability levels associated with most building or civil engineering structures. Then, the paper reviews different approaches to these problems and proposes the use of discrete-event simulation as the most realistic way to deal with them, specially during the design stage. The paper also reviews previous work on the use of both Monte Carlo simulation and discrete-event simulation in this area and shows how discrete-event simulation, in particular, could be employed to solve uncertainty in time-dependent structural reliability problems. Finally, a case study is developed to illustrate some of the concepts previously covered in the paper.