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Title: TASK-BASED LOAD FORECASTING AND ROBUST RESOURCE SCHEDULING IN SMART GRID
Creator: Han, Jiayu
Date: 2021
Description: In microgrids, the uncertainty of load and renewables and lack of generation capacity will lead to a wide variety of operation problems in...
Show moreIn microgrids, the uncertainty of load and renewables and lack of generation capacity will lead to a wide variety of operation problems in both grid-connected mode and islanded mode. This motivates the design of the state-of-art microgrid master controller for microgrid energy management, load forecasting, and demand response. Uncertainty in renewables and load is a great challenge for microgrid operation, especially in islanded mode as the microgrid may be small in size and has limited flexible resources. A multi-timescale, two-stage robust dispatch model is proposed to optimize the microgrid operation. The proposed one uses only one model to combine the hourly and sub-hourly dispatch together, which means the day-ahead hourly dispatch results must also satisfy the sub-hourly conditions. At the same time, the feasibility of the day-ahead dispatch result is verified in the worst-case condition considering the high-level uncertainty in renewable energy output and load consumptions. In addition, battery energy storage system (BESS) and solar PV units are integrated as a combined solar-storage system in the proposed model and the output power of the combined solar-storage system remains unchanged on an hourly basis. Furthermore, both BESS and thermal units provide regulating reserve to manage solar and load uncertainty. The model has been tested in a controller hardware in loop (CHIL) environment for the Bronzeville Community Microgrid system in Chicago. The simulation results show that the proposed model works effectively in managing the uncertainty in solar PV and load and can provide a flexible dispatch in both grid-connected and islanded modes.When the generation capacity of an islanded microgrid is less than the load demand, load curtailment is inevitable. This dissertation proposes a multi-objective optimization model to minimize the load curtailments. Specifically, the proposed model minimizes the generation cost and total load curtailments and also minimizes the maximum load curtailment. Furthermore, the impact of the penalty coefficients of total load curtailment and maximum load curtailment is analyzed, which provides a strategy to choose the value of the two penalty coefficients according to different practical purposes. The proposed model can be used in both microgrid generation scheduling and microgrid planning problems. It was tested in the Bronzeville Community Microgrid system and the results showed that the proposed model can reduce the total load curtailment and maximum load curtailment.Load forecasting is one of the most important and studied topics in modern power systems. However, traditional load forecasting is an open-loop process as it does not consider the end use of the forecasted load. This dissertation proposes a closed-loop task-based day-ahead load forecasting model labeled as LfEdNet that combines two individual layers in one model, including a load forecasting layer based on deep neural network (Lf layer) and a day-ahead stochastic economic dispatch (SED) layer (Ed layer). The training of LfEdNet aims to minimize the cost of the day-ahead SED in the Ed layer by updating the parameters of the Lf layer. Sequential quadratic programming (SQP) is used to solve the day-ahead SED in the Ed layer. The test results demonstrate that the forecasted results produced by LfEdNet can lead to lower cost of day-ahead SED at the expense of slight reduction in forecasting accuracy.
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Title: TOPOLOGY OPTIMIZATION OF SYNCHRONOUS ELECTRIC MACHINES
Creator: Guo, Feng
Date: 2021
Description: Topology optimization of electric machine is attractive because of the increased design degree of freedom compared to conventional electric...
Show moreTopology optimization of electric machine is attractive because of the increased design degree of freedom compared to conventional electric machine design techniques. Also, a topology optimization approach does not necessarily require the use of a geometric template where dimensions are controlled by parameters. In this dissertation, a density-based magneto-structural topology optimization approach for the design of synchronous reluctance machine (SynRel), interior permanent magnet synchronous machine (IPMSM), and wound field synchronous machine (WFSM) rotors is developed. Depending on the electric machine type, the optimization problems are divided into single material and multi-material topology optimizations. A mass thresholding function is introduced to overcome the intermediate density issue which is caused by combining the magnetic and structural topology optimization problems. SynRel and IPMSM optimization examples are presented in the single material topology optimization section. For the multi-material topology optimization, in order to properly define the boundary conditions between multiple materials, a virtual region calculation approach is proposed. In the WFSM topology optimization, the copper field winding is represented by a virtual region. The contact and frictionless boundary conditions between the copper field winding and the electrical steel is defined and the centripetal load of the copper winding are equivalently calculated and applied on the elements on the electrical steel next to the boundary between the copper field winding and the steel of the WFSM pole tip. In additional to the total free-form magneto-structural topology optimization, a density-based combined dimensional and topology optimization is developed for the design of IPMSM and WFSM rotors. Both the dimensional and topological control variables are integrated to simplify the optimization problem. For IPMSM rotor design, the permanent magnet (PM) block shape is preferred to be retained where dimensional optimization could be used. The proposed dimensional topology optimization approach can fit in this design situation, where the PM is designed using dimensional control variables where the rest of the design domain is optimized using topology optimization. To allow the block or rectangular magnet to move and change size, the surrounding design domain mesh must deform or distort. The Laplace's smoothing mesh deformation technique is used in this approach and helper lines are connected to allow greater mesh deformation range and to avoid over mesh distortion. In addition to IPMSMs, a WFSM example is presented optimizing the winding region using dimensional optimization and the rotor core using topology optimization. An alternative combined dimensional and topology optimization approach has also been developed primarily for the design of the IPMSM rotors. In this approach, the mesh deformation is not required but there is no explicit geometric boundary between the rectangular permanent magnet and the surrounding electrical steel and air. In this approach, the PM density is expressed as a Heaviside rectangular function of dimensional variables. The function is projected onto the rotor mesh. Modified material penalizations are used. Topology optimization then controls the deposition of electrical steel and air. Three different IPMSM examples are presented with different dimensional control variables, including the PM position, size and angle.
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Title: Child Temperament, Attachment, and Loneliness: The Mediating Effects of Social Competence
Creator: Evans, Lindsey M
Date: 2021
Description: Chronic loneliness is a risk factor associated with adverse psychological, physical, and academic outcomes. Converging evidence suggests that...
Show moreChronic loneliness is a risk factor associated with adverse psychological, physical, and academic outcomes. Converging evidence suggests that young children experience and can reliably report on their own loneliness. Due to the significant negative sequalae associated with childhood loneliness, it is critically important to examine risk factors for child loneliness. The aims of this study were two-fold: (a) to examine if temperament (i.e., negative affect, effortful control, and inhibitory control) and attachment security assessed at 4 years of age predict loneliness at age 6; and (b) to determine if social competence at age 5 mediates the relation between temperament and attachment security at age 4 and loneliness at age 6. Participants included a diverse sample of 796 4-year old children, about half of whom were male. At age 4, temperament was assessed with the Rothbart Child Behavior Questionnaire and three inhibitory control tasks, and attachment security was assessed with the Attachment Q-Sort. At age 5, the Social Skills Rating Scale was used to assess social competence, and, at age 6, loneliness was assessed with the Loneliness and Social Dissatisfaction Questionnaire. Results of hierarchical regression analyses indicated that lower levels of effortful control and inhibitory control at age 4 significantly predicted higher levels of loneliness at age 6. Also, lower levels of negative affect and higher levels of effortful control and attachment security at age 4 significantly predicted higher levels of social competence at age 5. However, social competence at age 5 did not predict loneliness at age 6. There was no evidence that social competence at age 5 mediated the relation between age 4 temperament, attachment security and age 6 loneliness. These findings reveal that early self-regulation is associated with later child-reported loneliness and that intervention for children who struggle with cognitive regulation may be effective in decreasing risk for later loneliness.
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Title: Inviscid Shock Propagation within a Variable-Geometry Scramjet Inlet
Creator: Grybko, Maciej
Date: 2021
Description: The study concerns the propagation of shockwaves within an inlet of a scramjet engine and effect of inlet geometry variation on performance. A...
Show moreThe study concerns the propagation of shockwaves within an inlet of a scramjet engine and effect of inlet geometry variation on performance. A Python code was developed to simulate and visualize a flowfield within a scramjet inlet, based on inviscid oblique shock theory. The program was validated against NASA Shock software, and the results differed only by round-off error (0.05%). Subsequently a geometric sensitivity study was conducted, showing that throughout acceleration from Mach 5 to Mach 20 parameters like inlet height could be varied to ensure constant number of shocks within an inlet (preventing discontinuous changes of flowfield), whereas lower wedge angle could control compression required for optimal combustion. Correspondingly, a trajectory was determined with a constraint on static pressure entering combustion chamber (100 kPa). For an arbitrary baseline inlet geometry, it was established that beyond Mach 10 the scramjet would exceed structural load limit, despite delivering sufficient conditions for rapid combustion. Nevertheless, below Mach 10 it would operate efficiently, proving that hydrocarbon-fueled scramjets can have a fixed geometry. For higher speeds, a variable geometry is a necessity.
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Title: ARE SUPPORTIVE FOSTER CAREGIVERS ASSOCIATED WITH IMPROVED FOSTER CARE ALUMNI OUTCOMES? A LONGITUDINAL EXAMINATION OF THE EFFECT OF SUPPORTIVE FOSTER CAREGIVERS ON MENTAL HEALTH OUTCOMES IN A NATIONALLY REPRESENTATIVE SAMPLE
Creator: Dunn, Megan Reeves
Date: 2021
Description: Foster youth are a vulnerable population associated with poor health outcomes, but relatively little research has identified factors that may...
Show moreFoster youth are a vulnerable population associated with poor health outcomes, but relatively little research has identified factors that may mitigate adverse outcomes for these youth. The present study augments previous research by utilizing a nationally representative, longitudinal study (The National Longitudinal Study of Adolescent to Adult Health or Add Health) to investigate whether foster youth in the United States face significantly different mental and behavioral health outcomes compared with same-age peers, and second, whether presence of a supportive foster caregiver may predict better mental and behavioral health outcomes in the foster youth subsample. Using data from Waves III and IV of the Add Health study (N = 12,288 participants, of which n = 282 were foster youth), analyses examined whether foster status and higher caregiver support was related to rates of depression symptoms, suicidal ideation, marijuana use, and alcohol use. Surprisingly, there were few differences between those with and without a foster history; higher frequency of marijuana use among foster youth was the only significant difference. However, analyses in the foster youth subsample indicated that the presence of a supportive caregiver was associated with lower rates of depression symptoms and lower endorsement of suicidal ideation, demonstrating caregiver support as a possible protective factor for foster youth. Future research must continue to explore potential benefits of caregiver support, as it may inform policy that can improve long-term outcomes for foster youth.
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Title: THE EFFECTS OF MODIFIED SURFACES ON INSULIN CRYSTALLIZATION
Creator: Hammadi, Okba Tahar
Date: 2021
Description: Engineered nucleation features (ENFs) were designed with the hope to improve the efficiency of protein crystallization and increase...
Show moreEngineered nucleation features (ENFs) were designed with the hope to improve the efficiency of protein crystallization and increase reproducibility both in quality and quantity. These ENFs were tested with human insulin as the protein of choice since it has flexible parameters, only one cofactor, and a large amount of commercially available crystal ready protein. Insulin crystallization on the ENFs will produce more crystals while also having a reduced crystallization on-set time compared to the control glass surface. The ENFs were compared to control surfaces under similar conditions and observed over time to record both onset-times and end times. The ENFs performed markedly better in on-set times, having an overall 87%-time reduction when compared to the control drops. The drops placed on the ENF produced more than 2.5x the number of crystals in the control drops.
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Title: THE EFFECTS OF COMMUNICATION MODALITY ON PRESENCE, COGNITIVE LOAD AND RETENTION IN SECOND LIFE
Creator: WILKES, STEPHANY FILIMON
Date: 2009-12
Description: This thesis reports findings from a study (N = 60) of the impact of three communication modalities (voice only, text only, and voice and text...
Show moreThis thesis reports findings from a study (N = 60) of the impact of three communication modalities (voice only, text only, and voice and text simultaneously) on cognitive load, as measured by subjective reports of mental effort; on learning, as measured by tests of recall and retention; and on perceptions of presence as measured by a Presence Questionnaire (Witmer & Singer, 2005). Based on the results of prior empirical research, it is hypothesized that retention scores will be higher for voice participants and voice-and-text participants than for text-only participants; that cognitive load will be lower for voice participants and higher for text conditions; that voice will contribute to greater perceptions to presence; and that higher perceptions of presence will not correlate with deeper learning. Study results indicate that communication modality significantly effected cognitive load (F(2, 54) = 4.58, p = .01) and retention (F(2, 54) = 3.53, p = .04), and that experience with and time spent in the virtual environment had significant effects on measures of cognitive load, retention, and presence: Significant between-subjects effects were found for cognitive load and time (p = .23), for retention and time (p = .21), and for retention and experience (p — .03).
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Title: Harold Leonard Stuart Building, Illinois Institute of Technology
Creator: Strohm, Adam
Date: 2015
Description: 10 West 31st Street, Chicago, Illinois
Collection: Building History project (buildinghistory.iit.edu)

Title: Arthur Keating Hall, Illinois Institute of Technology
Creator: Strohm, Adam
Date: 2015
Description: 3040 South Wabash Avenue, Chicago, Illinois
Collection: Building History project (buildinghistory.iit.edu)

Title: Arthur Keating Hall, Illinois Institute of Technology
Creator: Strohm, Adam
Date: 2015
Description: 3040 South Wabash Avenue, Chicago, Illinois
Collection: Building History project (buildinghistory.iit.edu)

Title: Graduate Hall, Illinois Institute of Technology
Creator: Strohm, Adam
Date: 2015
Description: 70 East 33rd Street, Chicago, Illinois
Collection: Building History project (buildinghistory.iit.edu)

Title: Cunningham Hall, Illinois Institute of Technology
Creator: Strohm, Adam
Date: 2015
Description: 3100 South Michigan Avenue, Chicago, Illinois
Collection: Building History project (buildinghistory.iit.edu)

Title: John T. Rettaliata Engineering Center, Illinois Institute of Technology
Creator: Strohm, Adam
Date: 2015
Description: 10 West 32nd Street, Chicago, Illinois
Collection: Building History project (buildinghistory.iit.edu)

Title: Heating Plant, Illinois Institute of Technology
Creator: Strohm, Adam
Date: 2015
Description: 3430 South Federal Street, Chicago, Illinois
Collection: Building History project (buildinghistory.iit.edu)

Title: Mixed foods in color
Creator: LeVant, Howard, LeVant Photography
Date: 1969-1978
Description: Photograph for unidentified grocery store chain. Date of photograph is unknown. Date range listed (1969-1978) is approximate. Title supplied...
Show morePhotograph for unidentified grocery store chain. Date of photograph is unknown. Date range listed (1969-1978) is approximate. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: Ann Geddes with cigarette
Creator: LeVant, Howard, LeVant Photography
Date: 1969-1978
Description: Model test taken by photographer Howard LeVant/LeVant Photography. Date of photograph is unknown. Date range listed (1969-1978) is approximate...
Show moreModel test taken by photographer Howard LeVant/LeVant Photography. Date of photograph is unknown. Date range listed (1969-1978) is approximate. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: Big Mama Panty Hose
Creator: LeVant, Howard, LeVant Photography
Date: 1972
Description: Photograph taken by photographer Howard LeVant/LeVant Photography for client Greenbaum Associates.
Collection: Howard LeVant papers, 1950-2020

Title: Judy Sharp…leggy
Creator: LeVant, Howard, LeVant Photography
Date: 1969-1978
Description: Model test taken by photographer Howard LeVant/LeVant Photography. Date of photograph is unknown. Date range listed (1969-1978) is approximate...
Show moreModel test taken by photographer Howard LeVant/LeVant Photography. Date of photograph is unknown. Date range listed (1969-1978) is approximate. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

Title: 1910 Surgery with nuns
Creator: LeVant, Howard, LeVant Photography
Date: 1969-1978
Description: Photograph taken by photographer Howard LeVant/LeVant Photography for the Klau-Van Pietersom-Dunlap (KVPD) agency and Kimberly-Clark. Date of...
Show morePhotograph taken by photographer Howard LeVant/LeVant Photography for the Klau-Van Pietersom-Dunlap (KVPD) agency and Kimberly-Clark. Date of photograph is unknown. Date range listed (1969-1978) is approximate. Title supplied by Howard LeVant
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Collection: Howard LeVant papers, 1950-2020

Title: Gas station newspapers
Creator: LeVant, Howard, LeVant Photography
Date: 1969-1978
Description: Photograph created by photographer Howard LeVant/LeVant Photography for the advertising firm D'arcy McManus. Date of photograph is unknown....
Show morePhotograph created by photographer Howard LeVant/LeVant Photography for the advertising firm D'arcy McManus. Date of photograph is unknown. Date range listed (1969-1978) is approximate. Title supplied by Howard LeVant.
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Collection: Howard LeVant papers, 1950-2020

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