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Adaptive Architectural Strategies For Resilient Energy-Aware Computing, Rizwan Arshad Ashraf Jan 2015

Adaptive Architectural Strategies For Resilient Energy-Aware Computing, Rizwan Arshad Ashraf

Electronic Theses and Dissertations

Reconfigurable logic or Field-Programmable Gate Array (FPGA) devices have the ability to dynamically adapt the computational circuit based on user-specified or operating-condition requirements. Such hardware platforms are utilized in this dissertation to develop adaptive techniques for achieving reliable and sustainable operation while autonomously meeting these requirements. In particular, the properties of resource uniformity and in-field reconfiguration via on-chip processors are exploited to implement Evolvable Hardware (EHW). EHW utilize genetic algorithms to realize logic circuits at runtime, as directed by the objective function. However, the size of problems solved using EHW as compared with traditional approaches has been limited to relatively …

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Opportunistic Networks In Campus Environments, Salih Safa Bacanli Jan 2015

Opportunistic Networks In Campus Environments, Salih Safa Bacanli

Electronic Theses and Dissertations

Opportunistic communication is an active research area in wireless sensor networks. Exploiting the opportunities to communicate between devices in an unstable network is one of the main challenges of the opportunistic communication. In this thesis, we propose an infrastructure-independent opportunistic mobile social networking strategy for efficient message broadcasting in campus environments. Specifically, we focus on the application scenario of university campuses. In our model, the students' smartphones forward messages to each other. The messages are created spontaneously as independent events in various places of the campus. The events can be either urgent security alerts or private announcements to the students …

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Examining Multiple Approaches For The Transferability Of Safety Performance Functions, Ahmed Tarek Ahmed Farid Jan 2015

Examining Multiple Approaches For The Transferability Of Safety Performance Functions, Ahmed Tarek Ahmed Farid

Electronic Theses and Dissertations

Safety performance functions (SPFs) are essential in road safety since they are used to predict crash frequencies. They are commonly applied for detecting hot spots in network screening and assessing whether road safety countermeasures are effective. In the Highway Safety Manual (HSM), SPFs are provided for several crash classifications for several types of roadway facilities. The SPFs of the HSM are developed using data from multiple states. In regions where jurisdiction specific SPFs are not available, it is custom to adopt nationwide SPFs for crash predictions then apply a calibration factor. Yet, the research is limited regarding the application of …

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Compressive Sensing And Recovery Of Structured Sparse Signals, Behzad Shahrasbi Jan 2015

Compressive Sensing And Recovery Of Structured Sparse Signals, Behzad Shahrasbi

Electronic Theses and Dissertations

In the recent years, numerous disciplines including telecommunications, medical imaging, computational biology, and neuroscience benefited from increasing applications of high dimensional datasets. This calls for efficient ways of data capturing and data processing. Compressive sensing (CS), which is introduced as an efficient sampling (data capturing) method, is addressing this need. It is well-known that the signals, which belong to an ambient high-dimensional space, have much smaller dimensionality in an appropriate domain. CS taps into this principle and dramatically reduces the number of samples that is required to be captured to avoid any distortion in the information content of the data. …

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Modeling Dense Storage Systems With Location Uncertainty, Mohamed Awwad Jan 2015

Modeling Dense Storage Systems With Location Uncertainty, Mohamed Awwad

Electronic Theses and Dissertations

This dissertation focuses on developing models to study the problem of searching and retrieving items in a dense storage environment. We consider a special storage configuration called an inverted T configuration, which has one horizontal and one vertical aisle. Inverted T configurations have fewer aisles than a traditional aisle-based storage environment. This increases the storage density; however, requires that some items to be moved out of the way to gain access to other more deeply stored items. Such movement can result in item location uncertainty. When items are requested for retrieval in a dense storage environment with item location uncertainty, …

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Modeling Social Norms In Real-World Agent-Based Simulations, Rahmatollah Beheshti Jan 2015

Modeling Social Norms In Real-World Agent-Based Simulations, Rahmatollah Beheshti

Electronic Theses and Dissertations

Studying and simulating social systems including human groups and societies can be a complex problem. In order to build a model that simulates humans' actions, it is necessary to consider the major factors that affect human behavior. Norms are one of these factors: social norms are the customary rules that govern behavior in groups and societies. Norms are everywhere around us, from the way people handshake or bow to the clothes they wear. They play a large role in determining our behaviors. Studies on norms are much older than the age of computer science, since normative studies have been a …

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Determination Of Frequency-Based Switch Triggers For Optimal Vibration Reduction Via Resonance Frequency Detuning, Garrett Lopp Jan 2015

Determination Of Frequency-Based Switch Triggers For Optimal Vibration Reduction Via Resonance Frequency Detuning, Garrett Lopp

Electronic Theses and Dissertations

Resonance frequency detuning (RFD) is a piezoelectric-based vibration reduction approach that applies to systems experiencing transient excitation through the system*s resonance—for example, turbomachinery experiencing changes in rotation speed, such as on spool-up and spool-down. This technique relies on the inclusion of piezoelectric material and manipulation of its electrical boundary conditions, which control the stiffness of the piezoelectric material. Resonance frequency detuning exploits this effect by intelligently switching between the open-circuit (high stiffness) and short-circuit (low stiffness) conditions as the excitation approaches resonance, subsequently shifting the natural frequency to avoid this resonance crossing and limit the response. The peak response dynamics …

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Resource Management In Large-Scale Systems, Ashkan Paya Jan 2015

Resource Management In Large-Scale Systems, Ashkan Paya

Electronic Theses and Dissertations

The focus of this thesis is resource management in large-scale systems. Our primary concerns are energy management and practical principles for self-organization and self-management. The main contributions of our work are: 1. Models. We proposed several models for different aspects of resource management, e.g., energy-aware load balancing and application scaling for the cloud ecosystem, hierarchical architecture model for self-organizing and self-manageable systems and a new cloud delivery model based on auction-driven self-organization approach. 2. Algorithms. We also proposed several different algorithms for the models described above. Algorithms such as coalition formation, combinatorial auctions and clustering algorithm for scale-free organizations of …

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An Integrated Framework For Automated Data Collection And Processing For Discrete Event Simulation Models, Carlos Rodriguez Jan 2015

An Integrated Framework For Automated Data Collection And Processing For Discrete Event Simulation Models, Carlos Rodriguez

Electronic Theses and Dissertations

Discrete Events Simulation (DES) is a powerful tool of modeling and analysis used in different disciplines. DES models require data in order to determine the different parameters that drive the simulations. The literature about DES input data management indicates that the preparation of necessary input data is often a highly manual process, which causes inefficiencies, significant time consumption and a negative user experience. The focus of this research investigation is addressing the manual data collection and processing (MDCAP) problem prevalent in DES projects. This research investigation presents an integrated framework to solve the MDCAP problem by classifying the data needed …

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Stability And Control In Complex Networks Of Dynamical Systems, Saeed Manaffam Jan 2015

Stability And Control In Complex Networks Of Dynamical Systems, Saeed Manaffam

Electronic Theses and Dissertations

Stability analysis of networked dynamical systems has been of interest in many disciplines such as biology and physics and chemistry with applications such as LASER cooling and plasma stability. These large networks are often modeled to have a completely random (Erdös-Rényi) or semi-random (Small-World) topologies. The former model is often used due to mathematical tractability while the latter has been shown to be a better model for most real life networks. The recent emergence of cyber physical systems, and in particular the smart grid, has given rise to a number of engineering questions regarding the control and optimization of such …

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Worldwide Infrastructure For Neuroevolution: A Modular Library To Turn Any Evolutionary Domain Into An Online Interactive Platform, Paul Szerlip Jan 2015

Worldwide Infrastructure For Neuroevolution: A Modular Library To Turn Any Evolutionary Domain Into An Online Interactive Platform, Paul Szerlip

Electronic Theses and Dissertations

Across many scientific disciplines, there has emerged an open opportunity to utilize the scale and reach of the Internet to collect scientific contributions from scientists and non-scientists alike. This process, called citizen science, has already shown great promise in the fields of biology and astronomy. Within the fields of artificial life (ALife) and evolutionary computation (EC) experiments in collaborative interactive evolution (CIE) have demonstrated the ability to collect thousands of experimental contributions from hundreds of users across the glob. However, such collaborative evolutionary systems can take nearly a year to build with a small team of researchers. This dissertation introduces …

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An Optimization Of Thermodynamic Efficiency Vs. Capacity For Communications Systems, Gregory Rawlins Jan 2015

An Optimization Of Thermodynamic Efficiency Vs. Capacity For Communications Systems, Gregory Rawlins

Electronic Theses and Dissertations

This work provides a fundamental view of the mechanisms which affect the power efficiency of communications processes along with a method for efficiency enhancement. Shannon's work is the definitive source for analyzing information capacity of a communications system but his formulation does not predict an efficiency relationship suitable for calculating the power consumption of a system, particularly for practical signals which may only approach the capacity limit. This work leverages Shannon's while providing additional insight through physical models which enable the calculation and improvement of efficiency for the encoding of signals. The proliferation of Mobile Communications platforms is challenging capacity …

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Improving Fmri Classification Through Network Deconvolution, Jacob Martinek Jan 2015

Improving Fmri Classification Through Network Deconvolution, Jacob Martinek

HIM 1990-2015

The structure of regional correlation graphs built from fMRI-derived data is frequently used in algorithms to automatically classify brain data. Transformation on the data is performed during pre-processing to remove irrelevant or inaccurate information to ensure that an accurate representation of the subject's resting-state connectivity is attained. Our research suggests and confirms that such pre-processed data still exhibits inherent transitivity, which is expected to obscure the true relationships between regions. This obfuscation prevents known solutions from developing an accurate understanding of a subject’s functional connectivity. By removing correlative transitivity, connectivity between regions is made more specific and automated classification is …

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Compendium Of Thermoviscoplasticity Modeling Parameters For Materials Under Non-Isothermal Fatigue, Nathan O'Nora Jan 2015

Compendium Of Thermoviscoplasticity Modeling Parameters For Materials Under Non-Isothermal Fatigue, Nathan O'Nora

HIM 1990-2015

Viscoplasticity models allow for the prediction of the inelastic behavior of materials, taking into account the rate-dependence. In order to model the response under non-isothermal conditions experienced by many components, such as those in turbomachinery, however, it is necessary to incorporate temperature-dependence. Additionally, for materials subjected to thermal shock, temperature rate-dependence is also important. The purpose of this research is to develop a method of determining Chaboche viscoplasticity parameters that allows for consistent behavior with changing temperature. A quartet of candidate materials, 304 stainless steel, IN617, DS GTD-111, and Ti6242S, were chosen for their applications in turbomachinery, such as gas …

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Enhanced Microwave Hyperthermia Using Nanoparticles, Maryory Urdaneta Jan 2015

Enhanced Microwave Hyperthermia Using Nanoparticles, Maryory Urdaneta

Electronic Theses and Dissertations

In this dissertation a study of enhanced hyperthermia for cancer treatment through the use of magnetic nanoparticles is presented. Hyperthermia has been in use for many years, as a potential alternative method in cancer treatment, and high frequency microwave radiation has been used successfully to raise the tumor temperature to around 42°C in superficial tumors without causing damage to surrounding healthy tissues. Magnetic fluid hyperthermia involves the use of magnetic nanoparticles injected into the tumor before exposure to microwave radiation. The magnetic energy in the nanoparticles is converted into heat allowing for a more rapid rise of temperature in the …

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Reasoning Tradeoffs In Implicit Invocation And Aspect Oriented Languages, Jose Sanchez Salazar Jan 2015

Reasoning Tradeoffs In Implicit Invocation And Aspect Oriented Languages, Jose Sanchez Salazar

Electronic Theses and Dissertations

To reason about a program means to state or conclude, by logical means, some properties the program exhibits; like its correctness according to certain expected behavior. The continuous need for more ambitious, more complex, and more dependable software systems demands for better mechanisms to modularize them and reason about their correctness. The reasoning process is affected by the design decisions made by the developer of the program and by the features supported by the programming language used. Beyond Object Orientation, Implicit Invocation and Aspect Oriented languages pose very hard reasoning challenges. Important tradeoffs must be considered while reasoning about a …

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Cascaded Digital Refinement For Intrinsic Evolvable Hardware, Vignesh Thangavel Jan 2015

Cascaded Digital Refinement For Intrinsic Evolvable Hardware, Vignesh Thangavel

Electronic Theses and Dissertations

Intrinsic evolution of reconfigurable hardware is sought to solve computational problems using the intrinsic processing behavior of System-on-Chip (SoC) platforms. SoC devices combine capabilities of analog and digital embedded components within a reconfigurable fabric under software control. A new technique is developed for these fabrics that leverages the digital resources' enhanced accuracy and signal refinement capability to improve circuit performance of the analog resources' which are providing low power processing and high computation rates. In particular, Differential Digital Correction (DDC) is developed utilizing an error metric computed from the evolved analog circuit to reconfigure the digital fabric thereby enhancing precision …

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A Macro-Level Sustainability Assessment Framework For Optimal Distribution Of Alternative Passenger Vehicles, Nuri Onat Jan 2015

A Macro-Level Sustainability Assessment Framework For Optimal Distribution Of Alternative Passenger Vehicles, Nuri Onat

Electronic Theses and Dissertations

Although there are many studies focusing on the environmental impacts of alternative vehicle options, social and economic dimensions and trade-off relationships among all of these impacts were not investigated sufficiently. Moreover, most economic analyses are limited to life cycle cost analyses and do not consider macro-level economic impacts. Therefore, this thesis aims to advance the Life Cycle Sustainability Assessment literature and electric vehicle sustainability research by presenting a novel combined application of Multi Criteria Decision Making techniques with Life Cycle Sustainability Assessment for decision analysis. With this motivation in mind, this research will construct a compromise-programming model (multi-objective optimization method) …

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Meshless Direct Numerical Simulation Of Turbulent Incompressible Flows, Andres Vidal Urbina Jan 2015

Meshless Direct Numerical Simulation Of Turbulent Incompressible Flows, Andres Vidal Urbina

Electronic Theses and Dissertations

A meshless direct pressure-velocity coupling procedure is presented to perform Direct Numerical Simulations (DNS) and Large Eddy Simulations (LES) of turbulent incompressible flows in regular and irregular geometries. The proposed method is a combination of several efficient techniques found in different Computational Fluid Dynamic (CFD) procedures and it is a major improvement of the algorithm published in 2007 by this author. This new procedure has very low numerical diffusion and some preliminary calculations with 2D steady state flows show that viscous effects become negligible faster that ever predicted numerically. The fundamental idea of this proposal lays on several important inconsistencies …

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Modified System Design And Implementation Of An Intelligent Assistive Robotic Manipulator, Nicholas Paperno Jan 2015

Modified System Design And Implementation Of An Intelligent Assistive Robotic Manipulator, Nicholas Paperno

Electronic Theses and Dissertations

This thesis presents three improvements to the current UCF MANUS systems. The first improvement modifies the existing fine motion controller into PI controller that has been optimized to prevent the object from leaving the view of the cameras used for visual servoing. This is achieved by adding a weight matrix to the proportional part of the controller that is constrained by an artificial ROI. When the feature points being used are approaching the boundaries of the ROI, the optimized controller weights are calculated using quadratic programming and added to the nominal proportional gain portion of the controller. The second improvement …

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Investigating Simulation-Based Pattern Recognition Training For Behavior Cue Detection, Crystal Maraj Jan 2015

Investigating Simulation-Based Pattern Recognition Training For Behavior Cue Detection, Crystal Maraj

Electronic Theses and Dissertations

The U.S. military uses pattern recognition training to observe anomalies in human behavior. An examination of the pattern recognition training literature for Warfighters reveals a gap in training to discern patterns of human behavior in live environments. Additionally, the current state of warfare is evolving and requires operations to change. As a result, pattern recognition training must accommodate new practices to improve performance. A technique used to improve memory for identifying patterns in the environment is Kim's game. Kim's game establishes patterns to identify inanimate objects, of which information retains in memory for later recall. The paper discusses the fundamental …

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Towards Improving Human-Robot Interaction For Social Robots, Saad Khan Jan 2015

Towards Improving Human-Robot Interaction For Social Robots, Saad Khan

Electronic Theses and Dissertations

Autonomous robots interacting with humans in a social setting must consider the social-cultural environment when pursuing their objectives. Thus the social robot must perceive and understand the social cultural environment in order to be able to explain and predict the actions of its human interaction partners. This dissertation contributes to the emerging field of human-robot interaction for social robots in the following ways: 1. We used the social calculus technique based on culture sanctioned social metrics (CSSMs) to quantify, analyze and predict the behavior of the robot, human soldiers and the public perception in the Market Patrol peacekeeping scenario. 2. …

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Providing Context To The Clues: Recovery And Reliability Of Location Data From Android Devices, Connie Bell Jan 2015

Providing Context To The Clues: Recovery And Reliability Of Location Data From Android Devices, Connie Bell

Electronic Theses and Dissertations

Mobile device data continues to increase in significance in both civil and criminal investigations. Location data is often of particular interest. To date, research has established that the devices are location aware, incorporate a variety of resources to obtain location information, and cache the information in various ways. However, a review of the existing research suggests varying degrees of reliability of any such recovered location data. In an effort to clarify the issue, this project offers case studies of multiple Android mobile devices utilized in controlled conditions with known settings and applications in documented locations. The study uses data recovered …

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A Generic Framework For Multi-Method Modeling And Simulation Of Complex Systems Using Discrete Event, System Dynamics And Agent Based Approaches., Konstantinos Mykoniatis Jan 2015

A Generic Framework For Multi-Method Modeling And Simulation Of Complex Systems Using Discrete Event, System Dynamics And Agent Based Approaches., Konstantinos Mykoniatis

Electronic Theses and Dissertations

Decisions about Modeling and Simulation (M&S) of Complex Systems (CS) need to be evaluated prior to implementation. Discrete Event (DE), System Dynamics (SD), and Agent Based (AB) are three different M&S approaches widely applied to enhance decision-making of complex systems. However, single type M&S approaches can face serious challenges in representing the overall multidimensional nature of CS and may result in the design of oversimplified models excluding important factors. Conceptual frameworks are necessary to offer useful guidance for combining and/or integrating different M&S approaches. Although several hybrid M&S frameworks have been described and are currently deployed, there is limited guidance …

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Integrated Maritime Simulation Complex Management, Quality And Training Effectiveness From The Perspective Of Modeling And Simulation In The State Of Florida, Usa (A Case Study), Yaser Sendi Jan 2015

Integrated Maritime Simulation Complex Management, Quality And Training Effectiveness From The Perspective Of Modeling And Simulation In The State Of Florida, Usa (A Case Study), Yaser Sendi

Electronic Theses and Dissertations

Naturally, maritime training simulators at all events are valuable instructional and pedagogical tools. Through the history, the maritime simulation was utilized to train prospective maritime apprentices in whom it has filled the gap left by the acute shortage of opportunities for jobs onboard vessels around the globe. However, professional seafarers are the axis of success and competitiveness in the field of maritime training. They are the ones that, who are well trained and have the responsibilities of their work and the surrounding environment. In order to achieve the success along with effective training skills, both maritime companies and seafarers should …

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Lyapunov-Based Robust And Adaptive Control Design For Nonlinear Uncertain Systems, Kun Zhang Jan 2015

Lyapunov-Based Robust And Adaptive Control Design For Nonlinear Uncertain Systems, Kun Zhang

Electronic Theses and Dissertations

The control of systems with uncertain nonlinear dynamics is an important field of control science attracting decades of focus. In this dissertation, four different control strategies are presented using sliding mode control, adaptive control, dynamic compensation, and neural network for a nonlinear aeroelastic system with bounded uncertainties and external disturbance. In Chapter 2, partial state feedback adaptive control designs are proposed for two different aeroelastic systems operating in unsteady flow. In Chapter 3, a continuous robust control design is proposed for a class of single input and single output system with uncertainties. An aeroelastic system with a trailingedge flap as …

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Mechanism Of Hip Dysplasia And Identification Of The Least Energy Path For Its Treatment By Using The Principle Of Stationary Potential Energy, Mohammed Abdulwahab M. Zwawi Jan 2015

Mechanism Of Hip Dysplasia And Identification Of The Least Energy Path For Its Treatment By Using The Principle Of Stationary Potential Energy, Mohammed Abdulwahab M. Zwawi

Electronic Theses and Dissertations

Developmental dysplasia of the hip (DDH) is a common newborn condition where the femoral head is not located in its natural position in the acetabulum (hip socket). Several treatment methods are being implemented worldwide to treat this abnormal condition. One of the most effective methods of treatment is the use of Pavlik Harness, which directs the femoral head toward the natural position inside the acetabulum. This dissertation presents a developed method for identifying the least energy path that the femoral head would follow during reduction. This is achieved by utilizing a validated computational biomechanical model that allows the determination of …

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Data-Driven Simulation Modeling Of Construction And Infrastructure Operations Using Process Knowledge Discovery, Reza Akhavian Jan 2015

Data-Driven Simulation Modeling Of Construction And Infrastructure Operations Using Process Knowledge Discovery, Reza Akhavian

Electronic Theses and Dissertations

Within the architecture, engineering, and construction (AEC) domain, simulation modeling is mainly used to facilitate decision-making by enabling the assessment of different operational plans and resource arrangements, that are otherwise difficult (if not impossible), expensive, or time consuming to be evaluated in real world settings. The accuracy of such models directly affects their reliability to serve as a basis for important decisions such as project completion time estimation and resource allocation. Compared to other industries, this is particularly important in construction and infrastructure projects due to the high resource costs and the societal impacts of these projects. Discrete event simulation …

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Propagation Of Unit Location Uncertainty In Dense Storage Environments, Patrick Reilly Jan 2015

Propagation Of Unit Location Uncertainty In Dense Storage Environments, Patrick Reilly

Electronic Theses and Dissertations

Effective space utilization is an important consideration in logistics systems and is especially important in dense storage environments. Dense storage systems provide high-space utilization; however, because not all items are immediately accessible, storage and retrieval operations often require shifting of other stored items in order to access the desired item, which results in item location uncertainty when asset tracking is insufficient. Given an initial certainty in item location, we use Markovian principles to quantify the growth of uncertainty as a function of retrieval requests and discover that the steady state probability distribution for any communicating class of storage locations approaches …

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Sustainability Assessment Of A Municipal Utility Complex: A System Of Systems Approach, Tarek Fahmy Jan 2015

Sustainability Assessment Of A Municipal Utility Complex: A System Of Systems Approach, Tarek Fahmy

Electronic Theses and Dissertations

Construction of municipal utility complexes has to support continuing population growth, economic development, and a widespread of social interest in environmental preservation. Municipalities face challenges in designing, constructing, and operating environmentally sustainable utility complexes, and their primary goal in developing such a complex is to minimize the environmental impact resulting from energy production and waste treatment (both liquid and solid), management, and disposal. However, decision and policy makers lack a system of systems approach that takes into account multiple interdependent systems comprised of the functional system (infrastructure, facilities, operations within the complex…), the economic system, the social/cultural system, and the …

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