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- Title
- CARING FOR THE CAREGIVER: INTERPERSONAL FACTORS AND DEPRESSION AS PARALLEL-SERIAL MEDIATORS BETWEEN STIGMA AND SUICIDAL IDEATION
- Creator
- Tsen, Jonathan Y.
- Date
- 2022
- Description
-
Background/Objectives: This study applied Joiner's Interpersonal PsychologicalTheory to a caregiver population, by describing relationships...
Show moreBackground/Objectives: This study applied Joiner's Interpersonal PsychologicalTheory to a caregiver population, by describing relationships among affiliate stigma, thwarted-belongingess (TB), perceived-burdensomeness (PB), and depression, and suicidal ideation (SI). Participants/Setting: 243 adult caregivers participated in this study via Prolific Academic and caregiver-related websites. Design/Main Outcome Measures: This study used a cross-sectional, survey-based design including demographics, the Affiliate Stigma Scale (α=.93), Interpersonal Needs Questionnaire-15 (α=.95), Center of Epidemiology Studies–Depression-10 (α=.90), and Depressive Symptom Inventory— Suicide Subscale (α = .91) via Qualtrics. Analyses run on SPSSv27/Hayes’ PROCESS macro. Results: Parallel-serial mediation found after controlling for covariates that the total indirect effect of affiliate stigma on SI through both TB and PB then through depression was significant, B = .0271, SE = .0062, β = .1659, 95%CI [.0152, .0393]. Conclusions: Findings indicated that affiliate stigma indirectly affected SI through both TB and PB then through depression. Interventions to improve caregiver wellbeing should capitalize on both improving interpersonal functioning and depressive symptoms in tandem in order to reduce SI risk.
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- Title
- Towards Understanding the Microstructure and Mechanical Properties of Additively Manufactured Ni-base Superalloys
- Creator
- Tiparti, Dhruv Reddy
- Date
- 2022
- Description
-
Nickel-base superalloy components such as turbine discs typically undergo numerous manufacturing steps that contribute to increasing the cost...
Show moreNickel-base superalloy components such as turbine discs typically undergo numerous manufacturing steps that contribute to increasing the cost and the waste of excess materials. With advent of fusion based additive of manufacturing (AM) techniques, such components with complex geometry can be fabricated with great efficiency. However due to characteristically high energy densities, fast cooling rate, and layer-by-layer building process associated with AM; Ni-base superalloys with higher temperature performance are difficult to be fabricated by AM due to susceptibility to composition related defect formation, which is further exacerbated by anisotropic grain structures induced by the large thermal gradients present. Crack-free material can be fabricated but, in most cases, issues such as an anisotropic microstructure will prevail, and the balance of mechanical properties achieved may not be suitable for the desired applications. Several strategies exist to mitigate the challenges posed by additive manufacturing via post-processing such as hot-isostatic processing, annealing heat treatments, application of grain refining inoculants, etc. All these strategies utilized to mitigate issues with AM of Ni-base superalloys still require further study to understand their effects on the microstructure and mechanical properties. This work aims to evaluate the use of inoculant particles, and novel heat treatments on the microstructure and mechanical properties of different superalloys. First, the effect of varying amounts of CoAl2O4 inoculant ranging from 0 to 2 wt.% on the microstructure evolution of Inconel 718(IN718) fabricated by selective laser melting (SLM) was evaluated. The findings from this study indicated that additions of CoAl2O4 only resulted in a minor degree of grain refinement with slight increase in anisotropy; in addition, a CoAl2O4 ¬content above 0.2 wt.% resulted in the formation of agglomerate inclusions; and that to effectively utilize CoAl2O4 as a grain refining inoculant, process parameters must be further optimized while considering the formation of agglomerates, and other defects. Second, the application of CoAl2¬O4 was extended towards the Direct Energy Deposition (DED) of IN718. Here findings indicated that due to the modification of the thermophysical properties of the melt pool by oxide addition, an earlier onset of large columnar extending across multiple layers occurred while counteracting conditions required for equiaxed grain formation; and these CoAl2O4 were also found to exhibit a potent Zenner pinning effect that maintained the as-built grain structure despite application of extreme high treatment condition of 1200oC for 4 hrs. Third, the tensile and fatigue properties of the DED IN718 with CoAl2O4 were evaluated. Here, it was found that the addition of CoAl2O4 leads to a minor increase in tensile strength in the as-built condition attributed primarily to the fine oxide dispersion; a more modest increase in tensile strength in the heat-treated condition due to grain refinement induced by retaining the as-built grain structure; and that despite the increase in tensile strength with CoAl2O4 a corresponding increase in fatigue life did not occur. Lastly, the processing of René 65 conducted by laser-powder bed fusion(L-PBF) was done and compared to the conventionally cast and wrought material. Here, the effect of the difference in processing route in conjunction with heat treatments was evaluated to understand the creep and stress relaxation behavior. It was found that L-PBF of René 65 led to an overall improved resistance to deformation by creep and relaxation mechanism.
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- Title
- Quality of Life in People with Epilepsy: The Associations of Anti-seizure Medications and Biopsychosocial Variables
- Creator
- Thomas, Julia A.
- Date
- 2022
- Description
-
People with epilepsy, on average, experience lower quality of life (QOL) than healthy controls (Taylor et al., 2011). This study examined the...
Show morePeople with epilepsy, on average, experience lower quality of life (QOL) than healthy controls (Taylor et al., 2011). This study examined the associations between specific anti-seizure medication, biopsychosocial factors, and QOL in people with epilepsy. Analysis of covariance revealed that individuals taking three or more anti-seizure medications had significantly lower QOL than those taking levetiracetam. Findings also demonstrated that when looking at biopsychosocial factors as predictors of QOL in hierarchical regression, anxiety, depression, and daytime sleepiness were significant predictors of QOL. Once these factors were entered into the model, number of medications was no longer significant. The final model predicted 59.6% of the variance in QOL. Lastly, a moderation analysis to examine the moderating effect of employment on the association between number of anti-seizure medications and QOL was not significant. Additional exploratory analyses looking at individuals who were employed versus those who were not employed were completed. These findings underscore the importance of addressing psychological health and sleep factors within the epilepsy population.
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- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
- Creator
- Brandt & Associates
- Date
- 1964
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking northeast.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1958
- Creator
- Brandt & Associates
- Date
- 1958
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking southwest.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1963
- Creator
- Brandt & Associates
- Date
- 1963
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1950
- Date
- 1950
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking southwest. Photographer unknown.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1940
- Date
- 1940
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north. Photographer unknown.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1975
- Creator
- Brandt & Associates, Ltd.
- Date
- 1975
- Description
-
Aerial photograph of Mies Campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1985
- Date
- 1985-10-24
- Description
-
Aerial photograph of Mies Campus, looking north, 1985. Photographer unknown.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
- Creator
- Brandt & Associates
- Date
- 1964
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1964
- Creator
- Brandt & Associates
- Date
- 1964
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1967
- Creator
- Brandt & Associates
- Date
- 1967
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking north.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, ca. 1955-1959
- Date
- 1955-1959
- Description
-
Aerial photograph of the Illinois Institute of Technology campus, looking southwest. Photographer unknown. Date of photograph unknown. Date...
Show moreAerial photograph of the Illinois Institute of Technology campus, looking southwest. Photographer unknown. Date of photograph unknown. Date range listed is approximate.
Show less - Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Aerial view of the Illinois Institute of Technology campus, Chicago, Illinois, 1957
- Date
- 1957
- Description
-
Aerial photograph of the south portion of the Illinois Institute of Technology campus, looking south. Photographer unknown.
- Collection
- IIT Campus Aerial photographs, 1940-2002
- Title
- Synthesis and Photophysical Characterization of Novel Organic Triplet Donor–Acceptor Dyads for Light-Harvesting/Modulation Application
- Creator
- Yun, Young Ju
- Date
- 2022
- Description
-
Donor–acceptor chromophoric systems (D–A) are important scaffolds for several light-harvesting/initiated processes and devices, including...
Show moreDonor–acceptor chromophoric systems (D–A) are important scaffolds for several light-harvesting/initiated processes and devices, including light-emitting diodes, photo-catalytic/redox systems, and photovoltaic cells. It has been hypothesized that for efficient photophysical processes (viz. energy/charge-transfer or excited-state interactions); it is ideal to tether the donor and acceptor chromophores into molecular dyads. To this end, I devised and synthesized several dyads by tethering an organic triplet energy donor and various polyaromatic chromophores (e.g., perylene derivatives and anthracene derivatives) onto a conjugated-/non-conjugated-linker (phenylene- and triptycene- linker, respectively). During the 4-5 years of my Ph.D., I synthesized a total of five (5) dyads: o–, p–3, and dyads 3–5. These systems were fully characterized using different spectroscopy tools/techniques. The spectroscopy investigations of the dyads have allowed me to decipher two important energy transfer pathways: through-bond and through-space with the phenylene linker and only through-space energy with the triptycene linker. Furthermore, the investigations led to the discovery that geometrical features such as face-to-face (co-facial) or slip-stacked interactions between the donor and acceptors chromophores might dictate the dynamic/kinetic of light-induced energy transfer in the dyads. Findings from my graduate research project paved the way for developing molecular engineering studies for light-harvesting/modulation applications.Subsequently, I was able to employ the dyads of my interest to achieve intramolecular and intermolecular triplet energy transfer (TEnT) triplet-triplet annihilation-based photon upconversion (TTA-PUC).
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- Title
- DEFAULT RISK AND MOMENTUM PREMIUM
- Creator
- Zhang, Yi
- Date
- 2022
- Description
-
Birge and Zhang (2018) reported that combining common factors models with functions of the default risk improves models' performance to...
Show moreBirge and Zhang (2018) reported that combining common factors models with functions of the default risk improves models' performance to explain stock returns. Default risk contains firm specific information and may help to explain momentum premium that compensates investors for the firm specific risk exposures. In this paper, we confirmed that the forward-looking measure of default risk, as proposed by Birge and Zhang (2018), seems to capture some pricing information in the momentum premium. This provides an alternative to explain the underlying risks associated with the momentum strategy.
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- Title
- INTEGRATED DECISION SUPPORT SYSTEM FOR THE SELECTION AND IMPLEMENTATION OF DELAY ANALYSIS IN CONSTRUCTION PROJECTS
- Creator
- Yang, Juneseok
- Date
- 2022
- Description
-
The goal of this study is to establish an objective, user-friendly, and reliable decision support system, called delay analysis selection and...
Show moreThe goal of this study is to establish an objective, user-friendly, and reliable decision support system, called delay analysis selection and implementation system (DASIS), which allows delay analysts and practitioners in the construction industry to select a type of delay analysis that is most appropriate for given conditions and to perform the selected type of delay analysis. DASIS integrates a delay analysis selection system (DASS) module and an implementation module (DAIS) that performs the type of delay analysis selected by DASS in construction projects.The model that operates the DASS module consists of (1) four different delay analysis approaches currently available to practitioners; (2) a set of 26 attributes that affect the selection of a type of delay analysis; (3) a case-base involving 3,776 cases described by these 26 attributes and their corresponding output values (i.e., the most appropriate delay analysis approach); (4) a set of 7 categories consisting of subsets of attributes; (5) the weights of the attributes and the categories; and (6) a spreadsheet designed in Microsoft Excel that performs the calculations involved in case-based similarity assessment. The implementation module is a computerized analytics and automation platform that performs the type of delay analysis selected by DASS. In developing the DASS module, 26 attributes that influence the selection of the most appropriate type of delay analysis were identified based on a thorough literature review and were organized in seven categories. These attributes were used to evaluate the four types of delay analysis (i.e., static, dynamic, additive, and subtractive analyses). Based on the results of this evaluation, a case-base of 3,776 cases was generated while considering the constraints of each category. The weights of the attributes and categories were determined by using several methods. To determine the best-fit between a target case (defined by its 26 attributes) and the 3,776 cases stored in the case-base were used to perform a case-based similarity assessment to calculate weighted case similarity scores, and to find the best-informed solution to the delay analysis type selection problem. In developing the DAIS module, the four types of delay analysis were coded in Microsoft Excel using macros programmed in Visual Basic for Applications (VBA). This automated tool performs the selected delay analysis by DASS. The fully integrated DASIS model finds the best-fit match between a target case and cases stored in the case-base by means of similarity assessment methods by using weighted case similarity scores, hence identifying the most appropriate type of delay analysis for use in the target case, performs the selected type of delay analysis and generates a report about the results of the delay analysis to the analyst instantaneously, allowing the contractual parties to settle the issues quickly. This study is the first attempt to establish an objective decision support system (DASS) to assist delay analysts by automating the selection of a type of delay analysis using combinations of well recognized and reliable attributes and similarity assessment techniques. In addition, DASS is immediately followed by DAIS in an integrated system (DASIS) that does not only do the selection of the most appropriate type of delay analysis, but that also implements the selected delay analysis, hence providing ease of use and high speed. A case study based on fictitious scenarios is presented to demonstrate and validate the research approach. The use of the entropy weight method to calculate the weights of the attributes can be considered a minor limitation of the study. Finally, DASIS can be reformulated as a web-based application that allows analysts to work online using ordinary browsers anywhere and anytime.
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- Title
- MEASUREMENT OF ELECTRON NEUTRINO AND ANTINEUTRINO APPEARANCE WITH THE NOνA EXPERIMENT
- Creator
- Yu, Shiqi
- Date
- 2020
- Description
-
As a long-baseline neutrino oscillation experiment, the NuMI Off-axis $\nu_e$ Appearance (NOvA) experiment aims at studying neutrino physics...
Show moreAs a long-baseline neutrino oscillation experiment, the NuMI Off-axis $\nu_e$ Appearance (NOvA) experiment aims at studying neutrino physics by measuring neutrino oscillation parameters using the neutrino flux from the Main Injector (NuMI) beam. It has two functionally identical detectors. The near detector is onsite at Fermi National Accelerator Laboratory. The far detector is 810 km away from the source of neutrinos and antineutrinos, at Ash River, Minnesota. At the near detector, muon neutrinos or antineutrinos, before significant oscillations take place, are used to correct the Monte Carlo simulation. At the far detector, the neutrino and antineutrino fluxes after significant oscillations have happened are measured and analyzed to study neutrino oscillation. The NOvA experiment is sensitive to the values of $\sin^2\theta_{23}$, $\Delta m^2_{32}$, and $\delta_{CP}$. The latest values from the NOvA 2020 analysis are as follows: $\sin^2\theta_{23}=0.57^{+0.03}_{-0.04}$, $\Delta m^2_{32}=(2.41\pm0.07)\times10^{-3}$ eV$^2$/c$^4$, and $\delta_{CP}=0.82\pi$ with a wide 1$\sigma$ interval of uncertainty. My study is focused on the neutrino oscillation analysis with NOvA, including detector light model tuning, particle classification with convolutional neural network, electron neutrino and antineutrino energy reconstruction, and oscillation background estimation. Most of my studies have been used in the latest NOvA publication and the NOvA 2020 analysis.
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- Title
- Towards Trustworthy Multiagent and Machine Learning Systems
- Creator
- Xie, Shangyu
- Date
- 2022
- Description
-
This dissertation aims to systematically research the "trustworthy" Multiagent and Machine Learning systems in the context of the Internet of...
Show moreThis dissertation aims to systematically research the "trustworthy" Multiagent and Machine Learning systems in the context of the Internet of Things (IoT) system, which mainly consists of two aspects: data privacy and robustness. Specifically, data privacy concerns about the protection of the data in one given system, i.e., the data identified to be sensitive or private cannot be disclosed directly to others; robustness refers to the ability of the system to defend/mitigate the potential attacks/threats, i.e., maintaining the stable and normal operation of one system.Starting from the smart grid, a representative multiagent system in the IoT, I demonstrate two works on improving data privacy and robustness in aspects of different applications, load balancing and energy trading, which integrates secure multiparty computation (SMC) protocols for normal computation to ensure data privacy. More significantly, the schemes can be readily extended to other applications in IoT, e.g., connected vehicles, mobile sensing systems.For the machine learning, I have studied two main areas, i.e., computer vision and natural language processing with the privacy and robustness correspondingly. I first present the comprehensive robustness evaluation study of the DNN-based video recognition systems with two novel proposed attacks in both test and training phase, i.e., adversarial and poisoning attacks. Besides, I also propose the adaptive defenses to fully evaluate such two attacks, which can thus further advance the robustness of system. I also propose the privacy evaluation for the language systems and show the practice to reveal and address the privacy risks in the language models. Finally, I demonstrate a private and efficient data computation framework with the cloud computing technology to provide more robust and private IoT systems.
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