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Title: DECISION SUPPORT SYSTEM FOR THE SELECTION OF BUILDING COMPONENTS USING MAINTAINABILITY PRINCIPLES
Creator: Liu, Xuanchang
Date: 2019
Description: Maintainability of a building component refers to how easy it is to maintain the component with minimum cost and downtime. Unfortunately,...
Show moreMaintainability of a building component refers to how easy it is to maintain the component with minimum cost and downtime. Unfortunately, maintainability issues do not receive enough attention in the design stage and cause serious problems in the post-construction stage such as increasing the life cycle cost of the facility, wasting maintenance materials, and unsatisfactory user experience because of downtime. These problems can be prevented if a tool is available that can help designers make the selection for building components based on maintainability in the design stage. This study aims to develop such a tool that allows designers to evaluate a building’s components relative to maintainability and that helps designers to make a maintainability-based selection in the design stage. To achieve this purpose, this study first identifies a checklist of maintenance actions for components of building systems, in this study condensers. Then, a condenser selector system is developed by coding in Java language. Users can run this selector with any browser with or without a connection to the Internet. This condenser selector system relies on a database that is populated by data about maintenance actions obtained from condensers’ guidebooks or from manufacturers. When using the selector, designers can customize the tool according to their preferences or conditions. At the end, the selector ranks the condensers in the database and allows the designer to make an informed maintainability-based selection. The prototype component selection system is a prototype, but can be expanded by augmenting the system to include other components too. Ideally, a maintainability-based selection tool should include all models of all components in building systems. Such a system could be a significant improvement in the current design practice. Considering the maintainability of components in the design stage could enhance maintenance and facility management.
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Title: Photochemical Reaction of Covalent Organic Frameworks: Probing the Changes in Surface Area and Topology of the Frameworks
Creator: Ye, Yuxin
Date: 2019
Description: Covalent organic frameworks (COFs) are a new class of 2-dimensional or 3-dimensional polymers that have rigid and porous structures. COFs are...
Show moreCovalent organic frameworks (COFs) are a new class of 2-dimensional or 3-dimensional polymers that have rigid and porous structures. COFs are widely applied in gas storage, catalysts, photo conductivity, and drug delivery. Since the applications of COFs are highly related to their structures, it is necessary to learn the stability of COFs under certain conditions. In this research, the stability of COFs towards light was mainly focused on. A new tetraphenyl substituted ketone based COF was synthesized and characterized with Fourier transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, ultraviolet-visible spectroscopy, and powder X-ray diffraction. Infrared spectra proved that this new COF can undergo Norrish type I reaction to release carbon monoxide under UV irradiation, while main structure of this COF was not broken. This thesis will detailly discussed the synthesis and characterization of this new COF, as well as the building blocks, linkers, and other precursors. This thesis will give some inspirations in the study of energy transfer in covalent organic frameworks.
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Title: MULTI-OBJECTIVE OPTIMIZATION FOR LEED - NEW CONSTRUCTION USING GENETIC ALGORITHMS
Creator: ALOTHAIMEEN, IBRAHEEM
Date: 2018
Description: In the U.S., the building sector is responsible for 73% of electricity usage, 38% of CO2 emissions, and 13.6% of potable water. These data...
Show moreIn the U.S., the building sector is responsible for 73% of electricity usage, 38% of CO2 emissions, and 13.6% of potable water. These data indicate that the construction industry negatively impacts the global environment and natural resources. The concept of “sustainability” was introduced to set guidelines for the construction industry to limit its negative environmental impact. To promote sustainability in the construction industry, many organizations have introduced guidelines and rating systems for buildings. One of these rating systems is Leadership in Energy and Environmental Design (LEED) which is the most globally acknowledged system.Although LEED excels in reducing the negative environmental impacts and the energy consumption of buildings, the high costs in the early phases associated with the implementation and pursuit of LEED certification are pushing away some project owners from entering the process. Therefore, to balance these objectives in sustainable projects, an approach which optimizes multiple objectives is needed. In this study, a multi-objective optimization framework, which uses Non-dominated Sorting Genetic Algorithm-II (NSGA-II), is proposed to find the optimal solution in terms of life-cycle cost and sustainability for a new construction project pursuing LEED v4 BD+C certification. A BIM project of a 3-floor educational building was selected as a case study in the research. The study case is used to verify the efficiency and soundness of the proposed model. The results show that the method does indeed lead to optimal solutions.
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Title: QUINODIZATION REACTION OF NAPHTHALENE DIIMIDES TO AFFORD NOVEL P-NAPHTHOQUINODIMETHANE LIGHT-HARVESTING CHROMOPHORES: AROMATICITY, PHOTOPHYSICS AND APPLICATION FOR PHOTON UPCONVERSION
Creator: Shokri, Siamak
Date: 2018
Description: ABSTRACT The chemistry and aromaticity of polycyclic benzenoid hydrocarbons have been a topic of intensive investigations since the early 19th...
Show moreABSTRACT The chemistry and aromaticity of polycyclic benzenoid hydrocarbons have been a topic of intensive investigations since the early 19th century. The concept of aromaticity has played a crucial role in organic chemistry and related fields; and it expanded very rapidly for its ability to explain the stability, electronic structures and physical properties of π-conjugated molecules. Besides benzenoid structures, chemists have also investigated quinoidal systems, which have been shown to exhibit unique aromaticity and physical properties in the ground state. Notably, it is customary to draw quinoidal polycycles as a mixture of closed– and open–shell structures. While closed–shell quinoids do exhibit interesting physical and electronic properties, the open–shell forms can be related to benzenoids with the presence of radicals or unpaired electrons. In this context, it has been demonstrated that open–shell quinoids can have both singlet and triplet multiplicity in their ground state. In this thesis, I will demonstrate that this feature can be tuned/suppressed through clever design of the molecular framework that contains a quinoidal moiety. Often, quinoids can be labeled as aromatic like benzenoids or (anti)/pro-aromatic depending on the molecular framework. Before labeling a quinoidal compound as aromatic or (anti)/pro-aromatic, it is important to define the different aromaticity rules and their influence on the corresponding physical and electronic properties of the system(s) of interest. Chemists have relied on two main aromaticity rules (Hückel vs. Baird) to predict the nature, electronic, and physical properties of quinoidal structures and related systems. We proposed and synthesized novel quinoidal naphthalene derivatives (QDM) that exhibit “compromised” aromaticity in the ground state. A combination of computation and photophysical methods were employed to: i) decipher the reaction mechanism during the formation of the new poly-heterocyclic structures, ii) investigate their ground state and excited state opto-electronic properties, and iii) explore the nature and aromaticity of the corresponding excited state species. Additionally, the QDM was used as light-harvesting triplet sensitizers to achieve photon upconversion. This dissertation will first present a historical perspective in the investigation of various polycyclic aromatic systems that exhibit interesting aromaticity. Then, in chapter 2, I will detail the synthetic route and corresponding mechanism during the preparation of thio-QDM. The characterization and photophysical properties including the transient absorption spectra and excited state dynamics and kinetics of these chromophores will also be discussed. In chapter 3, I will discuss the use of QDM as light-harvesting energy donor to sensitize perylene and achieve triplet-triplet annihilation photon upconversion. The mechanism of this non-linear photophysical process will also be highlighted. Finally, the conclusion chapter will introduce future perspectives in the synthesis of derivatives of QDM.
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Title: INDUSTRIALIZED BUILDING CONSTRUCTION MODELS FOR TORNADO AFTERMATH RECOVERY
Creator: Alves de Carvalho, Augusto
Date: 2019
Description: Some researchers have reported that the number of disasters is expanding in scale and occurrences. Today, humanity occupies more land than...
Show moreSome researchers have reported that the number of disasters is expanding in scale and occurrences. Today, humanity occupies more land than forty years ago. Due to this, existing communities are prone to higher chances of being affected by disasters. Consequently, the number of natural disasters and losses have increased through time. Recent research work indicates that construction of new houses takes the majority of the recovery time; for example, In Joplin tornado aftermath, the development of new houses took the longest part of the recovery time (D. J. Smith & Sutter, 2013). The disaster industry sees housing and shelter as a product. The procurement is done on a necessity basis. The product --tents, inter-shelters, trailers, permanent dwellings, or any property to rent-- has to be ready whenever required. Therefore, after calculating the construction capacity in tornado regions, a methodology is proposed to compare four different robust industrialized building construction alternatives, keeping components, modules, and pieces in stock. Comparing them will provide information about which format is more appropriate for a profitable company or even a public entity, to respond and recover from a disaster faster.
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Title: The Role of Ethnic Similarity, Perceived Communication Style Deviation, and Cultural Intelligence in Leader-Member Exchange and Trust
Creator: Polyashuk, Yelena
Date: 2019
Description: This study examined those factors that contribute to a better working relationship between a leader and a subordinate or make that working...
Show moreThis study examined those factors that contribute to a better working relationship between a leader and a subordinate or make that working relationship challenging. Specifically, we investigated the effect of ethnic configuration within the leader-subordinate dyad and perceived dissimilarity on Leader-Member Exchange (LMX) and trust. Communication style deviation was tested as a mediator between actual, as well as perceived dissimilarity and relational outcomes. Cultural Intelligence (CQ) was included as a moderator, the presence of which could ameliorate the negative impact of dissimilarity on LMX and trust. In order to test these predictions, a survey was administered to 614 participants. Participants were working students at an urban, Midwestern, public university. Results showed that in presence of low CQ among respondents, there was a negative impact of ethnic dissimilarity on LMX. However, no impact of ethnic similarity/dissimilarity on trust was found. Specific dyad composition of the leader-subordinate dyad had no significant impact on LMX or trust. Finally, communication style deviation partially mediated the relationship between perceived dissimilarity and the two outcome variables of LMX and trust. These findings revealed that in order to build a high-quality relationship within an ethnically diverse leader-subordinate dyad, both CQ and alignment in communication style are of consequence.
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Title: Unsupervised Learning of Visual Odometry Using Direct Motion Modeling
Creator: Andrei, Silviu Stefan
Date: 2020
Description: Data for supervised learning of ego-motion and depth from video is scarce and expensive to produce. Subsequently, recent work has focused on...
Show moreData for supervised learning of ego-motion and depth from video is scarce and expensive to produce. Subsequently, recent work has focused on unsupervised learning methods and achieved remarkable results which surpass in some instances the accuracy of supervised methods. Many unsupervised approaches rely on predicted monocular depth and so ignore motion information. Moreover, unsupervised methods which do incorporate motion information do so only indirectly by designing the depth prediction network as an RNN. Hence, none of the existing methods model motion directly. In this work, we show that it is possible to achieve superior pose estimation results by modeling motion explicitly. Our method uses a novel learning-based formulation for depth propagation and refinement which transforms predicted depth maps from the current frame onto the next frame where it serves as a prior for predicting the next frame's depth map. Experimental results demonstrate that the proposed approach surpasses state of the art techniques for the pose prediction task while being better or on par with other methods for the depth prediction task.
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Title: AN EMPIRICAL APPROACH TO GASSIFICATION PROCESS MODELING AND ASSESSMENT
Creator: Rahmaninejad, Fatemeh
Date: 2013-05-01, 2013-05
Description: There has been growing interest in estimating the flow rate and composition of fuel gases produced from gasification of coal and other...
Show moreThere has been growing interest in estimating the flow rate and composition of fuel gases produced from gasification of coal and other carbonaceous solid fuels. In general, coal gasification processes are complex, and because of the high costs associated with the experimental investigations, modeling and simulation tools are needed to assist with the design, analysis, and optimization of these complex processes. Most of the efforts in the development of gasifier models have focused on two different approaches; equilibrium modeling and kinetic modeling. The chemical equilibrium approach assumes the gasification reactions have sufficiently fast kinetics and reach global chemical reaction equilibria, which leads to over-prediction of the extent of the gasification reactions [1, 2, 3]. On the other hand, the kinetic based models require detailed knowledge of hydrodynamic and reaction kinetics of the heterogeneous and homogeneous chemical reactions [4, 5]. Because of the dependence of the product gas (composition and flow rate) on a broad ranges of certain key operating variables such as gasifier design, configuration, and coal type the gasification model needs to take into account the effect of those parameters based on available experimental data. In this study, a versatile and user-friendly gasifier simulation model was developed which incorporates a MS Excel interface aiming to provide a guide to gasification process analysis, evaluation and improvement. The model uses a set of empirical “default” correlations, for the reaction conversions that were obtained from xi regression analysis of the available experimental data to predict the syngas composition, flow rate, and performance of the gasifier based on the operating conditions specified by the user. The results of the parametric studies performed for assessment of the effect of operating conditions are discussed and presented.
M.S. in Chemical Engineering, May 2013
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Title: Exploring the experience of work-family conflict among low-wage, immigrant workers
Creator: Pickett, Meghan
Date: 2019
Description: Work-family conflict is a well-studied and long-standing construct; however, there is a fundamental gap in our understanding of the construct...
Show moreWork-family conflict is a well-studied and long-standing construct; however, there is a fundamental gap in our understanding of the construct when it is applied to minority populations. The current study considered a unique group who sit at an intersection of challenges – low-wage, immigrant workers – to identify if traditional antecedents were predictive in this new group. Additional conceptualizations of work-family conflict are also considered. Results suggest that typical antecedents do not display the same significance and that alternative measures of work-family conflict should be considered. Conclusions and implications to the study of work-family conflict research are discussed.
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Title: Temporal and Spatial Properties of the Negative Bold Response in the DMN
Creator: Gholipour Picha, Saman
Date: 2024
Description: The Negative Blood Oxygen Level Dependent (BOLD) Response (NBR) remains less explored than its positive counterpart (PBR) in functional...
Show moreThe Negative Blood Oxygen Level Dependent (BOLD) Response (NBR) remains less explored than its positive counterpart (PBR) in functional Magnetic Resonance Imaging (fMRI) studies. This dissertation aims to advance the understanding of the NBR by investigating its task-specific spatial patterns, comparing its specificity to the PBR, validating its reproducibility across different subject groups, examining its relationship with functional connectivity patterns during cognitive tasks, and assessing its linearity with respect to stimulus duration.Firstly, we analyzed the spatial patterns of NBR and PBR across a diverse set of cognitive tasks using a novel paradigm that grouped twelve tasks into four cognitive domains. Our findings revealed that both NBR and PBR exhibit distinct, task-specific spatial patterns, with the NBR predominantly occurring within the Default Mode Network (DMN). Notably, the NBR demonstrated greater task specificity compared to the PBR, suggesting a unique role in differentiating cognitive processes. To validate these observations, we replicated the analyses in a separate cohort, confirming the reproducibility and consistency of the task-specific NBR spatial patterns across different subject groups. This consistency underscores the reliability of NBR patterns and their potential generalizability. Additionally, we investigated the functional connectivity patterns of major brain networks during cognitive tasks. Our analyses showed that functional connectivity within networks such as the DMN and the dorsal attention network (DAN) remained stable across different tasks. This implies that task-specific BOLD signal changes are likely not due to alterations in functional connectivity but result from local neural dynamics. Furthermore, we assessed the linearity of the NBR with respect to stimulus duration. Contrary to our initial hypothesis, the NBR did not exhibit a clear linear relationship with stimulus duration, differing from the established linearity of the PBR. This suggests fundamental differences in neurovascular coupling mechanisms between positive and negative BOLD responses and indicates that linear models may not suffice for accurately analyzing NBR data. Methodologically, we developed a robust fMRI data analysis pipeline incorporating motion correction, distortion correction using TopUp, spatial normalization via an in-house technique utilizing outputs from FreeSurfer and ANTs, and noise reduction through ICA-AROMA. This pipeline ensured high-quality preprocessing and reliable first-level statistical analyses. In conclusion, this research enhances the understanding of the NBR by highlighting its greater task specificity and non-linearity compared to the PBR. The findings emphasize the importance of considering both activation and deactivation processes in cognitive neuroscience. They have significant implications for theoretical models of brain function, analytical approaches in fMRI research, and potential clinical applications, paving the way for future investigations into the complex dynamics of neural activation and deactivation.
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Title: CO2 CAPTURE AND HYDROGEN PRODUCTION IN SORBENT ENHANCED WATER-GAS SHIFT (SEWGS) PROCESS WITH REGENERABLE SOLID SORBENT
Creator: Zarghami Khanehsar, Shahin
Date: 2015, 2015-07
Description: Carbon dioxide emission from fossil fuel combustion and its impact on global warming is one of the most critical environmental issues nowadays...
Show moreCarbon dioxide emission from fossil fuel combustion and its impact on global warming is one of the most critical environmental issues nowadays. Coal as a main source of produce energy is the most CO2-intensive fossil fuel. Advanced power generation processes that use gasification technology, such as Integrated Gasification Combined Cycle (IGCC), which offer higher efficiency, are among the leading contenders for power generation in the 21st century. In an IGCC process, because of high pressure, carbon dioxide in the fuel gas is at higher concentration, which can be captured and sequestered at lower costs. Utilization of regenerable MgO-based sorbents has been shown to be an effective method for capturing CO2 from gasification-based processes at elevated temperatures and pressures (i.e. p > 20 atm and 330° < T < 450°C). Low cost MgO based sorbent can be prepared through modification of natural dolomite. The reactivity of the sorbent in carbonation/regeneration cycles has a significant impact on the economics of the proposed regenerable process. Although the sorbent can be regenerated in successive cycles, the sorbent reactivity and capacity gradually decline during the cyclic process. Therefore, it is crucial to develop a better understanding on the role of the key parameters affecting the reactivity of the sorbent going through the cyclic carbonation/regeneration process. In this work, a systematic study on the sorbent preparation parameters (i.e., calcination temperature, calcination duration, calcination temperature ramp, potassium concentration, impregnation duration, drying temperature, re-calcination temperature, and re-calcination duration) was conducted to understand the effect of each parameter on the overall capacity and reactivity of the sorbent. The concentration of potassium additive (as carbonation reaction promoter) has the most significant effect on the reactivity of the sorbent and the optimum K/Mg molar ratio appears to be in the range of 0.1-0.16. The reactivity of the sorbent toward carbon dioxide at various operating conditions (i.e. temperature, CO2 concentration and steam concentration) was experimentally evaluated. The presence of steam significantly improves the reactivity of the sorbent which is attributed to formation of more favorable pore structure as well as the existence of a parallel carbonation reaction pathway involving the formation of a transient MgO.H2O* compound. The optimum carbonation reaction temperature in the presence of steam is around 380˚C. The effect of cycling on CO2 capture capacity of MgO-based sorbent was also experimentally investigated in this work. Series of carbonation/regeneration cycles (up to 25) have been carried out in a dispersed bed reactor to determine the effect of various variables on long term durability of the sorbent. The gradual loss of CO2 sorption capacity appears to be mainly due to loss potassium (a carbonation reaction promoter) in the cyclic process. Durability of the sorbents improves in the presence of steam, which is likely due to the favorable changes in the pore structure of the sorbents. A kinetic model was developed to fit the reactivity curves obtained from the dispersed bed tests at different operating conditions which was needed to predict the sorbent/catalyst performance in the regenerative process. Model parameters were defined and discussed for each of the operating conditions, as well as dispersed bed cyclic tests. Furthermore, the thermal behavior and the kinetics of partial decomposition of dolomite were studied in a dispersed-bed reactor to improve the reactivity of the sorbent. The microstructure and the nature of the solid products were found to be strongly dependent on the CO2 partial pressure near the reacting interface and on the decomposition temperature. A significant increase in the rate of the dolomite decomposition reaction was found in the presence of steam. Steam improves the kinetics of decomposition, modifies the radial distribution of the pores; and improves the connectivity of the pores inside the dolomite particles, which decreases the diffusion resistance of produced carbon dioxide inside the particle. A shrinking core model with variable product layer diffusivity was used to fit the experimental data and determine the kinetic parameters of the dolomite decomposition reaction. The results indicate that transport of CO2 across the reacting interface in the porous particle was the main limiting factor in the decomposition reaction at the experimental conditions investigated. A lab-scaled high-pressure/high-temperature packed-bed reactor was utilized to evaluate the performance of the sorbent in simultaneous water-gas shift reaction and sorbent carbonation environment. It was shown that the CO2 in the coal gas can be removed by regenerable MgO-based sorbents at temperatures around 350°C, and the CO2 removal can shift WGS reaction to enhance hydrogen production. Therefore, Sorbent Enhanced Water-Gas-Shift (SEWGS) can result in much higher hydrogen production without lowering the temperature, leading to higher overall process efficiency.
Ph.D. in Chemical Engineering, July 2015
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Title: THE RELATIONS OF LEADER EMPOWERING BEHAVIORS ON EMPLOYEE PERFORMANCE: MODERATED BY GENDER DYAD COMPOSITION
Creator: Zigun, David J
Date: 2016, 2016-07
Description: This study examined the possible moderating effect of gender dyadic composition on the relationship between Leadership Empowering Behaviors ...
Show moreThis study examined the possible moderating effect of gender dyadic composition on the relationship between Leadership Empowering Behaviors (LEBs) and employee performance across 221 supervisor-subordinate dyads in a Fortune 500 Midwestern U.S. company. The relationships between LEBs and employee performance moderated by gender dyadic composition were examined, as well as possible group differences of LEB ratings between gender dyad group membership. The goal of this study was to test the moderating role of gender dyadic composition on the relationship between LEBs and employee performance. This study obtained both supervisor ratings of employee performance and employee ratings of LEBs, allowing for the use of multi-source data. Results supported the expected relationship between LEBs and employee performance but neither indications of a moderating effect by gender dyads were found, nor were there group differences in perceptions of LEBs. This study adds to the existing literature because previous research has predominantly focused on examining employee perceptions of LEBs and related outcomes, but this was the first study to explore the potential moderating effect of gender dyads in this relationship. Implications of this study are explored.
M.S. in Psychology, July 2016
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Title: OPTIMAL MATERIAL SELECTION MODEL FOR LEED CERTIFICATION USING GENETIC ALGORITHMS
Creator: Kim, Taehyoung
Date: 2012-12-16, 2012-12
Description: Material selection is an important part of building design because it has great impact on the environment, as buildings during/after...
Show moreMaterial selection is an important part of building design because it has great impact on the environment, as buildings during/after construction are responsible for a large portion of carbon emissions and use many resources and considerable energy. Selecting green materials is an emergent issue in both design firms and construction companies. Green building certification such as LEED systems originated from the desire to improve environmental, economic, financial, and social benefits. The current approach to material selection for sustainability is based only on the designer’s past experiences. An arbitrary approach based on subjective opinions causes unnecessary expense, longer construction duration, and failure to meet desired environmental goals. In order to help decision-makers with the selection of the right materials, this study proposes a model that uses Genetic Algorithms in MATLAB and that optimizes the desired points in LEED Certification within budget constraints. This model can be applied to any project that is pursuing LEED Certification. If the user specifies the desired LEED points, the system recommends the least expensive combination of materials extracted from a database containing detailed information about a large member of materials. The modified model uses multi-objective genetic algorithms to establish trade-off between budget constraints and LEED points. The proposed system is expected to be a useful tool for inexperienced designers and a valuable guideline for designers with extensive experience.
M.S. in Civil Engineering, December 2012
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Title: AUTOMATED PROGRESS CONTROL USING LASER SCANNING TECHNOLOGY
Creator: Zhang, Chengyi
Date: 2013, 2013-05
Description: Assessing progress in different construction activities at the end of every payment period is time consuming and requires specialized...
Show moreAssessing progress in different construction activities at the end of every payment period is time consuming and requires specialized personnel employed by the contractor and the owner. Automatic progress control that requires a minimum amount of human involvement could reduce the time spent on this activity, reduce the number of personnel used, reduce the cost involved, reduce disagreements between contractor and owner, and add to the overall efficiency of project management. Attempts have been made in the past to resolve this issue using image processing and other techniques but the results have not been satisfactory. A new attempt was made to set up a system that can assess progress control with minimum human input and the results are presented in this paper. The experiment made use of laser scanning technology and was conducted both in laboratory conditions and construction sites. The initial results from laboratory condition appear to be promising but there are still obstacles to surmount. The system is robust and accurate in laboratory conditions and constitutes proof of concept. Improvements are made to accelerate the registration process of multiple scans, to reduce the noise data, to recognize objects of irregular shape, and to assess the practicality and economic feasibility of such a system when applying this system in real construction sites. Keywords: Construction scheduling, progress control, laser scanning
PH.D in Civil Engineering, May 2013
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Title: COMPUTATIONAL FLUID DYNAMICS AND POPULATION BALANCE MODEL FOR SIMULATION OF DRY SORBENT BASED CO2 CAPTURE PROCESS
Creator: Abbasi, Emadoddin
Date: 2013, 2013-12
Description: Carbon capture and sequestration (CCS) is one of the key technologies needed to mitigate carbon dioxide emission from industrial sources and...
Show moreCarbon capture and sequestration (CCS) is one of the key technologies needed to mitigate carbon dioxide emission from industrial sources and power plants. Development of CFD-based design tool for prediction of the extent of CO2 capture in a regenerable dry sorbent-based technology, in an efficient power plant design (i.e., modern IGCC power plants) was the driving force behind this project. In this study, we established a systematic methodology, starting from investigating the properties of the sorbent and its reaction mechanism, to developing a model for design and scale-up of the reactors that is needed to deploy this technology at larger scales. This dissertation provides a coupled CFD-PBE model based on the novel FCMOM approach with broad application in reaction engineering and reactor design where the polydisperse nature of the phases has strong effect on the hydrodynamics of the system. Detailed investigations of the MgO-based sorbent and its performance toward capturing CO2 from a coal gas stream were performed that result in development of the two-zone variable diffusivity shrinking core reaction model. Furthermore, a baseline design for a circulating fluidized bed (CFB) reactor, using numerical modeling and threedimensional simulations of a full-loop circulating fluidized bed reactor was provided based on the coupled CFD-PBE, which in combination with the reaction model can perform as a base for parametric studies and optimization of the process.
PH.D in Chemical Engineering, December 2013
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Title: THE EXAMINATION OF EFFORT TESTS: IDENTIFYING AN EFFICIENT APPROACH TO THE ASSESSMENT OF MALINGERING
Creator: Van De Kreeke, Diana
Date: 2013, 2013-05
Description: Malingering is an important issue in neuropsychology. A person can malinger both cognitive and psychological symptoms and it is important for...
Show moreMalingering is an important issue in neuropsychology. A person can malinger both cognitive and psychological symptoms and it is important for a clinician to assess for this possibility as malingering invalidates test findings. Several embedded and standalone effort tests exist for the purpose of malingering classification. This study looked to assess the effectiveness of embedded cognitive effort measures as compared to standalone effort measures. Additionally, the effectiveness of a smaller set of measures versus a larger set was analyzed for both cognitive and psychological measures. The likelihood of a person malingering both cognitive and psychological symptoms was assessed. Lastly, exploratory analyses were conducted to assess for differences between malingerers and non-malingerers. It was discovered that the California Verbal Learning Test-Second Edition-Forced Choice and the Victoria Symptom Validity Test were poor estimators of malingering classification. Therefore, the cognitive effort measures included in the analyses were the Reliable Digit Span, Rey 15-Item Test, Word Memory Test, and the Test of Memory Malingering. Psychological measures included the F and FBS indices from the Minnesota Multiphasic Personality Inventory-2 and the Negative Impression Management and Malingering Index scales from the Personality Assessment Inventory. Findings revealed that stand-alone tests add a significant amount of variance to malingering classification over and above embedded measures in a cognitive test battery. The most effective set of cognitive effort tests included the Reliable Digit Span, Rey 15-Item Test, and Word Memory Test. The Test of Memory Malingering did not add significant additional variance to the classification of malingering. Results showed that a vii person is not likely to malinger both cognitive and psychological symptoms. Lastly, the F and Negative Impression Management indices were just as effective at classifying malingering as when the FBS and Malingering Index scales were also used. Future research should further assess the actual sensitivities of the California Verbal Learning Test-Second Edition-Forced Choice and the Victoria Symptom Validity Test. Also, research should assess whether different cut off scores for the Test of Memory Malingering lead to increased efficiency of the measure for malingering classification.
PH.D in Psychology, May 2013
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Title: WEB-BASED CONTEMPORANEOUS DELAY ANALYSIS
Creator: Pektas, Murat
Date: 2011-11-22, 2011-12
Description: The construction industry is fragmented due to the many stakeholders and the diverse phases involved in a construction project. On time,...
Show moreThe construction industry is fragmented due to the many stakeholders and the diverse phases involved in a construction project. On time, within budget, with required quality are essentials of a successful project. However, most construction projects are faced with delays, which obstruct success. To recover the damage caused by delays, both the delays and the parties responsible for them should be identified accurately. Daily window delay analysis outperforms other delay analysis methods, but it requires intensive day-by-day information. The information flow among the project stakeholders must be smooth and speedy at all stages of the production process not only to achieve the basic project objectives but also to let project stakeholders recognize the delays and the parties responsible for them in order to recover time and cost. The Internet is attractive for transferring information promptly and economically with no regional or temporal borders. To merge the power of the Internet and to ease time consuming delay analysis, a web-based application is proposed to analyze delays effectively and contemporaneously, to reduce time and cost, and to provide historical data. The application considers the day-by-day variation in critical path(s) during the project life cycle. The application gives accurate and repeatable results for apportioning project delays, accelerations and decelerations among involved parties. The manual effort required by traditional systems is minimized with the application’s simple, easy to use, yet effective and highly automated features. Moreover, the database structure of the application is designed to store and manage more than one project at a time to let its users calculate the overall performance of the company including all projects, and to calculate average durations for activities that can come up in future projects.
M.S. in Civil Engineering, December 2011
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Title: TASK/STAFFING-TECHNOLOGY FIT IN CONSTRUCTION SCHEDULING
Creator: Yang, Juneseok
Date: 2015, 2015-07
Description: Construction managers use scheduling methods such as the critical path method (CPM) and linear scheduling methods (LSM) to improve the outcome...
Show moreConstruction managers use scheduling methods such as the critical path method (CPM) and linear scheduling methods (LSM) to improve the outcome of their project. CPM is a popular scheduling method that is mostly based on precedence relationships and the identification of the longest path through a network. LSMs are based on a continuous flow of resources and are used mostly on projects that exhibit repetitive characteristics. Despite the many obvious advantages of CPM, its use in construction has been limited. LSMs are much less frequently used than CPM, although the general consensus is that LSMs are quite effective in projects composed of activities of repetitive nature. Understanding the reasons why these methods are not used as extensively as expected could improve their level of acceptance in the construction industry. The link between construction scheduling methods and the tasks expected to be performed by schedulers has been an on-going concern in the construction industry. The link between construction scheduling methods and the capabilities of the scheduling staff has also been an important issue. This study proposes a combined task/staffing-technology fit model to understand why CPM and LSM are not used as extensively as expected in construction scheduling: (1) a task-technology fit model that aims to measure the extent to which a construction scheduling method functionally matches the tasks expected to be performed by the scheduling staff; (2) a staffing-technology fit model that aims to measure the extent to which a construction scheduling method matches the staff`s experience, know-how and capabilities. The models that are proposed are an answer to the lack of proper instruments for evaluating the extent to which scheduling methods are used in the industry. A questionnaire survey was administered to professionals listed in the directory of the Construction Management Association of America (CMAA) who have many years of experience in construction scheduling. Statistical analyses were performed to determine statistical significance of the differences between the level of agreement concerning task-technology fit and staffing-technology fit for CPM and LSM applications. Findings indicate that there are significant differences between the opinions of CPM users and LSM users. This means that task-technology fit is much different in CPM and LSM applications. Similarly, staffing-technology fit is also quite different in CPM and LSM applications.
M.S. in Civil Engineering, July 2015
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Title: Technology News, February 16, 1951
Collection: Technology News Microfilm collection, 1928-1981

Title: Simulation, design and applications of a table top analyzer-based phase contrast mammography system
Creator: Caudevilla Torras, Oriol
Date: 2019
Description: Analyzer-based Imaging is a promising phase contrast technology with huge potential for soft tissue imaging. Unlike absorption-contrast...
Show moreAnalyzer-based Imaging is a promising phase contrast technology with huge potential for soft tissue imaging. Unlike absorption-contrast methods, phase-contrast modalities measure refraction and scatter properties of the tissue. Such images are particularly suitable for applications such as mammography.The potential advantages of the Analyzer-Based Imaging technology are three fold. First, it shows exceptional contrast when imaging soft tissue, which produces extremely sharp images of the breast compared to absorption images. Second, it provides additional insights about the breast. In particular, the density and scatter images of breast micro-calcifications can help assessing their malignancy better than common mammograms. Third, it has shown potential to reduce the radiation dose deposited in the breast tissue by an order of magnitude compared to common mammography procedures.In the past, Analyzer-Based Imaging has been mainly developed with synchrotron light sources and focused on obtaining micro-resolution images. For such applications, quasi-monoenergetic beams are required. Nevertheless, monochromatic radiation can be easily obtained in synchrotron setups by filtering the source’s spectrum with crystal optics. Since synchrotrons are very brilliant sources, most of their radiation can be filtered out and still obtain low noise phase contrast images. Nowadays, there is a lot of interest in transitioning the technology to a table-top system using compact X-ray sources for mammography. However, compact sources are several orders of magnitude less brilliant, which causes extremely long exposure times. Additionally, the trade-off between exposure time (throughput) and resolution in compact analyzer-based imaging systems is yet to be completely understood.In this thesis, we lay down the principles to develop compact analyzer-based imaging systems capable of imaging a full-sized breast under ten seconds, while ensuring a resolution under 100 microns. This represents a major breakthrough towards obtaining a clinical analyzer-based mammography system. Additionally, we explore a unique application of the analyzer-based technology for breast diagnosis consisting on the assessment of the chemical composition of micro-calcifications. In conjunction with ABI’s unparalleled image quality, determining the chemical composition of micro- calcifications can help to mitigate the high false positive rate in common mammography.
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