Dulcy M. Abraham

Assessment technologies for sewer system rehabilitation

Due to their low visibility, rehabilitation of underground utilities is neglected until a catastrophic failure occurs. This results in costly and difficult rehabilitation options. A key issue governing the selection of appropriate rehabilitation technologies, is the availability of adequate information concerning the condition of infrastructure. This paper presents an overview of the current methods and new developments for sewer line condition assessment. The focus of the paper is on internal inspection technologies, which investigate infiltration/inflow problems, and assess the structural conditions of sewer pipes. The primary internal inspection method is closed-circuit television (CCTV) inspection. The quality of information obtained using traditional CCTV is dependent on the experience and skill of the technician and the reliability of the TV picture. Other non-destructive, remote-sensing diagnostic methods include: infrared thermography system, sonic distance measurement method and ground penetrating radar technique. The features of three new promising multi-sensory systems, namely, KARO, PIRAT and SSET, are explained. The paper also discusses ongoing research efforts for automated interpretation of multi-sensory data.

Exploring the Dimensions of Systems of Innovation Analysis: A System of Systems Framework

The objective of this paper is to propose an analysis framework based on the System of Systems approach to overcome existing methodological problems in System of Innovation studies. The concept of System of Innovation has been an important focus of innovation policy studies over the last decade. These studies have concentrated on structuring theoretical frameworks to assess the determinants of innovation processes using systems analysis principles. Despite about 20 years of research, System of Innovation has yet to become a theoretical framework. This paper reviews the relevant literature in an attempt to identify the challenges that System of Innovation studies face in structuring theoretical frameworks. The primary reason for the challenges appears to be that Systems of Innovation have been analyzed as monolithic systems when, in reality, Systems of Innovation are Systems of Systems, which have different features than monolithic systems. Different dimensions of assessment of System of Systems analysis are therefore required in System of Innovation studies. Three dimensions of System of Innovation analysis (definition, abstraction, and modeling) are introduced here to provide an analysis framework for Systems of Innovation studies. The proposed system-of-systems-based analysis framework (called Innovation System of Systems) would resolve the methodological challenges that System of Innovation studies are confronting in developing theoretical frameworks. Thus, it is capable of being tested by other researchers in the area of Systems of Innovation to advance the state of knowledge.

Allocating security resources to a water supply network

This paper develops a method for allocating a security budget to a water supply network so as to maximize the networks resilience to physical attack. The method integrates max-min linear programming, hydraulic simulation, and genetic algorithms for constraint generation. The objective is to find a security allocation that maximizes an attackers marginal cost of inflicting damage through the destruction of network components. We illustrate the method on two example networks, one large and one small, and investigate its allocation effectiveness and computational characteristics.

Application of dynamic programming and simulation for sewer management

This paper proposes a decision‐making framework to assist asset managers in decision making regarding sewer maintenance/rehabilitation (M&R) plans under constraints of limited access to sewer condition data. It discusses the application of probabilistic dynamic programming in conjunction with a Markov chain model to analyze the life cycle cost of combined sewer systems. M&R issues have traditionally been addressed with a crisis‐based approach, but this study contributes to sewer infrastructure management efforts in developing a management system based on life cycle cost analysis. The framework includes the optimal M&R techniques for sewer projects and the optimal times of application. The role of simulation is also explored to obtain the variability of the total cost. By knowing the expected costs and their variabilities, a deeper understanding of life cycle costs of sewer infrastructure can be obtained. The model’s capability is enhanced further by testing its sensivitity to varying discount and inflatio...

Ex-Ante Policy Analysis in Civil Infrastructure Systems

According to the National Academy of Engineering, innovations such as intelligent transportation systems, alternative fuels, and smart grids are critical to enhancing the resilience and sustainability of infrastructure systems. One key to realizing infrastructure innovations is effective policymaking based on a comprehensive analysis of the system. However, policy analysis in infrastructure systems is difficult because of the existence of complex adaptive behaviors and uncertainties. The objective of this paper is to create an ex-ante analysis framework using Agent-Based simulation to facilitate incorporation of uncertainties and complex adaptive behaviors of stakeholders in the analysis of infrastructure policies. The proposed framework includes three phases: definition, abstraction, and implementation. First, the steps in each phase will be discussed. Then, the application of the framework is demonstrated for the assessment of financial innovation policies for U.S. transportation infrastructure. Using hybrid agent-based/system dynamics techniques, a computational model is created to simulate the micro behaviors of state departments of transportation, private institutional investors, and the public. The results of the model include the visualization of the outcomes of different policies and the identification of the desired policy landscapes. The proposed framework provides policymakers with an integrated methodology through which an infrastructure policy problem is formulated, micro behaviors of the agents are modeled, the policy landscape is created, and the desired scenarios are identified.

Evaluation of flexibility in capital investments of infrastructure systems

Purpose – The purpose of this paper is to present a methodology to evaluate the capital investments in infrastructure projects managed by private operators considering uncertainties in the operation and maintenance of the infrastructure components.Design/methodology/approach – The methodology described in this paper is based on two major sources of information: deterioration curves of the infrastructure systems obtained from Markov chain models and the value of flexibility obtained from a real options analysis.Findings – Using this methodology, it is possible to determine whether there is value if project managers adopt flexible strategies in determining capital investments. These strategies refer to the opportunities of postponing, deferring or canceling capital investments required to maintain the operation of the infrastructure systems.Research limitations/implications – The model utilizes Monte Carlo simulation and real options analysis to overcome the complexities associated with the solution of the ...

Hybrid Approach to the Study of Inter-Organization High Performance Teams

AbstractAs construction projects increase in scale and complexity, a major challenge is to ensure the effective transfer of relevant information to the right entities to make decisions, manage conflict, and solve challenges, which will allow organizations to achieve the goals of the project. Project teams whose members have the necessary attitudes, competencies, and skills to overcome this challenge are often termed high performing teams (HPTs). Building on recent studies about HPTs, this paper proposes a hybrid methodology that uses network theory and the jobs-to-be-done framework for the study of teams that aspire to develop high performance. Social network analysis (SNA) provides a reactive approach to the study of team connectivity and hierarchical leadership patterns and is complemented by the jobs-to-be-done framework that focuses on the drivers of the behavior of the various project organizations. The paper demonstrates these concepts by analyzing the characteristics of HPTs through a case study on...

CONSTRUCTION WORK ZONE SAFETY

The need of maintaining safety of motorists and workers during periods of construction activities on interstates has prompted the Indiana Department of Transportation (INDOT) to initiate a study aimed at improving the safety in work zones on rural interstates. The two main objectives of the project are 1) determine if active warning devices or improved signing have an impact in work zone safety and 2) determine if it is appropriate to consider temporary roads and bridges during construction activity on interstates in an effort to maintain two lanes open at all times. This report describes the methods used to meet the objectives set forth by INDOT. The report has been subdivided into four major parts. A review of current work zone practices was conducted in neighboring states and abroad, and is presented in the first part of the report. The second part of the report contains an evaluation of several traffic management technologies that are currently available for interstate work zones. The goal of the evaluation was to determine the benefit INDOT would gain from using a technology of this type. The third part of the report presents the experimentation and testing conducted during the research project. This part discusses the accident data evaluation conducted in several interstate work zone projects in the state of Indiana. This portion of the report also presents the description of the test pilot project that included the deployment and evaluation of a series of fixed signs in conjunction with variable message signs in the I-65/US-30 reconstruction project near Merrillville, Indiana. The fourth part of the report covers the evaluation conducted to determine the feasibility of maintaining two lanes open at all times during work zones on interstates. An economic model was developed to provide INDOT with a preliminary tool for deciding if two lanes open should be maintained in a particular project. Along with the model is a case study that provides INDOT with an example of the staging required to complete the highway project in several seasons.

System‐of‐systems approach for assessment of financial innovations in infrastructure

Purpose – The purpose of the study presented in this paper is to assess determinants of financial innovations in infrastructure using a system‐of‐systems approach, and to demonstrate this approach in the context of the US highway transportation sector.Design/methodology/approach – A system‐of‐systems approach is adopted for systemic assessment. Data obtained from a case‐based research approach and a survey deployed to the state Departments of Transportation in the US is utilized in parallel with a network analysis to explore the status quo, key players and interactions, and the drivers of financial innovations for infrastructure.Findings – The findings include constructs regarding the players, practices, and activities and also a conceptual model relating to the drivers of financial innovations.Practical implications – The model along with the constructs provides an analytical tool for understanding the dynamics of financial innovations. Such understanding would lead to expansion of the creation and diffu...

Effectiveness of Speed Control Measures on Nighttime Construction and Maintenance Projects

Nighttime work-zone safety has become a concern among state transportation agencies due to an increasing number of work-zone fatalities and the high percentage of roadwork performed at night. Speed control has been determined by numerous researchers to be one of the best ways to improve safety on nighttime work zones. This paper presents an empirical analysis of speed control strategies for nighttime interstate construction and maintenance projects in Indiana. The analysis considers the effect of various speed control measures on the mean speed and the standard deviation of speed through nighttime work zones. Using a seemingly unrelated regression modeling approach, our analysis revealed that the presence of police enforcement, a high percentage of semi trucks in the traffic stream, and a high traffic flow significantly reduced mean work-zone speeds. Factors found to significantly increase mean work-zone speeds included an increase in the number of open lanes, an original speed limit of the road section greater than 60 mph, an increase in the distance between the work-zone speed limit signs and the first cone/barrel in the construction zone taper, and the progression of time through the night. The standard deviation of vehicle speeds was found to be significantly lower before midnight and as the number of vehicles queued increased. And it was found to be significantly higher with an increase in the number of open lanes through the work zone, an increase in the number of work-site speed-limit signs, a high percentage of personal vehicles in the traffic, and an increase in total traffic flow. The results from this research demonstrate a useful analysis methodology (seemingly unrelated regression estimation) and provide some empirical results that can provide guidance for transportation agencies and contractors to improve speed-control strategies in nighttime work zones.