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(961 - 980 of 4,544)
Pages
- Title
- DEVELOPMENT OF PHASED TWIN FLIP-FLOP JETS
- Creator
- Raman, G, Rice, Ej
- Date
- 1994-07
- Publisher
- ASME-AMER SOC MECHANICAL ENG
- Description
-
The flip-flop nozzle is a device that can produce an oscillating jet flow without any moving parts. There is now a renewed interest in such...
Show moreThe flip-flop nozzle is a device that can produce an oscillating jet flow without any moving parts. There is now a renewed interest in such nozzles due to their potential for use as excitation devices in practical applications. An experiment aimed at developing twin flip-flop jets that operate at prescribed frequencies and phase differences was performed. The phasing was achieved using two different nozzle interconnection schemes. In one configuration the two jets flapped in-phase and in another they flapped out-of-phase with respect to each other. In either configuration the frequencies of oscillation of both jets were equal. When one of the jets was run at a constant high velocity and the velocity of the second jet was increased gradually, the higher velocity jet determined the frequency of oscillation of both jets. The two flip-flop jet configurations described in this paper could be used to excite a primary jet flow in either an anti-symmetric (sinuous) or a symmetric (varicose) mode.
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- Title
- Orthotics and Prosthetics in Latin America (sequence unknown), IPRO 309 - Deliverables: IPRO 309 Brochure F09
- Creator
- Ashley, Trevor, Claxton, Matt, Conover, Stephen, Gotanco, Francis, Mathai, Alexander, Nizich, Adam, Park, Yong, Quikr, Kerry, Ray, Monmayuri, Vasquez, Raul
- Date
- 2009-12
- Description
-
The overall goal of our IPRO team is to create a program for delivering orthotics and prosthetics that is sustainable. This will be...
Show moreThe overall goal of our IPRO team is to create a program for delivering orthotics and prosthetics that is sustainable. This will be accomplished by improving the quality of the product by increasing availability of funding, improving cost effectiveness of prosthetics, and promoting awareness of treatment available.
Deliverables for IPRO 309: Orthotics and Prosthetics in Latin America for the fall 2009 semester.
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- Title
- An adaptive robust M-estimator for nonparametric nonlinear system identification
- Creator
- Wu, X. C., Cinar, A.
- Date
- 1996-08
- Publisher
- BUTTERWORTH-HEINEMANN LTD
- Description
-
An adaptive robust M-estimator for nonparametric nonlinear system identification is proposed. This M-estimator is optimal over a broad class...
Show moreAn adaptive robust M-estimator for nonparametric nonlinear system identification is proposed. This M-estimator is optimal over a broad class of distributions in the sense of maximum likelihood estimation. The error distributions are described by the generalized exponential distribution family. It combines nonparametric regression techniques to form a powerful procedure for nonlinear system identification. The adaptive procedure's excellent performance characteristics are illustrated in a Monte Carlo study by comparing the results with previous methods.
Endnote format citation
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- Title
- EXPLORING THE SHEAR-AND-TIME DEPENDENT DEGRADATION OF VON WILLEBRAND FACTOR UNDER VENTRICULAR ASSIST DEVICE-RELATED FLOW CONDITIONS
- Creator
- Yang, Shuo
- Date
- 2015, 2015-12
- Description
-
Abnormalities in VWF can cause impaired blood coagulation which results in higher bleeding tendency in patients with this disorder. Alteration...
Show moreAbnormalities in VWF can cause impaired blood coagulation which results in higher bleeding tendency in patients with this disorder. Alteration in VWF is characteristic in ventricular assist devices (VADs) implanted subjects with failing hearts. The nature of the abnormalities produced and the conditions which produce such abnormalities are not fully understood. The studies in this thesis investigate quantitatively the effects of VADs and VAD-related flow conditions on VWF degradation. This thesis consists of three studies: 1) an in vitro VAD loop study in which was investigated the degradation effects of three VADs either under preclinical development (VAD I) or being commercially available (VAD II & III); 2) a viscometer shear study in which was investigated a variety of factors under the controlled condition of a modified Couette viscometer, namely, shear stress, exposure time, pulsatile frequency and protease function, with respect to VWF degradation 3) a tubular shear study in which was investigated the relative degradation effects of shear stress versus exposure time under more VAD-related shear stresses (10 - 100 times higher than physiological levels) and exposure times of miliseconds. In the VAD flow loop, significant VWF degradation induced by VADs wee observed with an approximately 95% loss of high molecular weight VWF by 60 minutes. In the viscometer and the tubular studies, the factors studied enhanced VWF degradation in the following manner: increased shear stress above physiological levels, prolonged exposure time and higher pulsatile shear frequency were associated with greater degradation; shear stress was a more dominant factor than exposure time with respect to the degradation; and a various shear stress regions demonstrated maximal degradation effects. In addition, calcium-dependent protease function was a necessity for VWF degradation at all shear stress levels investigated. The studies also revealed that the unfolding of VWF to expose the cleavage sites appeared to take more time under shear than the refolding to re-cover those sites under static conditions. Critical shear regions may be important for unfolding and degrading VWF multimers of various sizes.
Ph.D. in Biomedical Engineering, December 2015
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- Title
- Interpreting ECG data by integrating statistical and artificial intelligence tools
- Creator
- Tatara, E., Cinar, A.
- Date
- 2002-01
- Publisher
- IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
- Description
-
The use of an automated system integrating data conditioning, statistical methods, and artificial intelligence tools to summarize and...
Show moreThe use of an automated system integrating data conditioning, statistical methods, and artificial intelligence tools to summarize and interpret high-frequency physiological data such as the electrocardiogram is investigated. The development of a methodology and its associated tools for real-time patient monitoring and diagnosis is accomplished by using the commercial programming environments MATLAB and G2, a real-time knowledge-based system (KBS) development shell. Data interpretation and classification is performed by integrating statistical classification methods and knowledge-based techniques with a graphical user interface that provides quick access to the analysis results as well as the original data. A KBS was developed that incorporates various statistical methods with a rule-based decision system to detect abnormal situations, provide preliminary interpretation and diagnosis, and to report these findings to the healthcare provider
Endnote format citation
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- Title
- TOPICS IN COUNTERPARTY RISK AND DYNAMIC CONIC FINANCE
- Creator
- Iyigunler, Ismail
- Date
- 2012-11-02, 2012-12
- Description
-
This thesis consists of three essays about modeling counterparty risk and pricing derivative securities. In the rst essay, we analyze the...
Show moreThis thesis consists of three essays about modeling counterparty risk and pricing derivative securities. In the rst essay, we analyze the counterparty risk embedded in CDS contracts, in presence of a bilateral margin agreement. We focus on the pricing of collateralized counterparty risk, and we derive the bilateral Credit Valuation Adjustment (CVA), unilateral Credit Valuation Adjustment (UCVA), and Debt Valuation Adjustment (DVA). We propose a model for the collateral by incorporating all related factors such as the thresholds, haircuts and margin period of risk. We derive the dynamics of the bilateral CVA in a general form with related jump martingales. Counterparty risky and the counterparty risk-free spread dynamics are derived and the dynamics of the Spread Value Adjustment (SVA) is found as a consequence. We nally employ a Markovian copula model for default intensities and illustrate our ndings with numerical results. In the second essay we address the issue of computation of the bilateral CVA under rating triggers in presence of ratings-linked margin agreements. We consider collateralized OTC contracts, that are subject to rating triggers, between two parties { an investor and a counterparty. Moreover, we model the margin process as a function of the credit ratings of the counterparty and the investor. We employ a Markovian approach for modeling of the rating transitions and of the default probabilities of the counterparties. In this framework, we derive the representation for bilateral CVA. We also introduce a new component in the decomposition of the counterparty risky price: namely the rating valuation adjustment (RVA) that accounts for the rating triggers. We consider several dynamic collateralization schemes where the margin thresholds are linked to the credit ratings of the counterparties. We account for the rehypothecation risk in the presence of independent amounts. Our results are ix illustrated in terms of a CDS contract and an IRS contract. In the third essay, we study the problem of pricing in incomplete markets with risk measures and acceptability indices. We propose a model for nding the dynamic ask and bid prices of derivative securities using Dynamic Coherent Acceptability Indices (DCAI) in the presence of transaction costs. In this framework, we de ne and prove a representation theorem for dynamic bid ask prices. We show that our prices can be computed using dynamic Gain-Loss Ratio (dGLR), which is a DCAI. To illustrate our results, we provide several numerical examples, by pricing barrier options with dGLR.
PH.D in Applied Mathematics, December 2012
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- Title
- A METHODOLOGY FOR UTILIZATION OF DEGRADED WATER IN THERMOELECTRIC POWER PLANT COOLING SYSTEMS
- Creator
- Safari, Iman
- Date
- 2013, 2013-12
- Description
-
The overall objective of this study was to develop a comprehensive methodology to identify viable treatment strategies for utilization of...
Show moreThe overall objective of this study was to develop a comprehensive methodology to identify viable treatment strategies for utilization of degraded waters for cooling in thermoelectric power systems. To achieve this objective a process simulation model was developed using Aspen Plus® with the OLI (OLI System, Inc.) water chemistry model to predict water quality and the rate of fouling in the recirculating cooling loop utilizing secondary-treated municipal wastewater (MWW) and tertiary-treated municipal wastewater as the sources of makeup water. This process simulation model includes sub- models for pre-treatment units; the cooling tower with water, CO2, and NH3 evaporation; as well as the recirculating cooling system and condenser with salt precipitation and fouling. The input parameters of the model, including CO2 mass transfer coefficients in the cooling tower and kinetics of salts precipitation reactions, were determined by developing mathematical models and calibrating the models with the experimental data obtained from literature. The process simulation module was used to predict the water quality in the recirculating cooling loop and the results were compared with pilot-scale experimental data from literature on makeup water alkalinity, loop pH and ammonia evaporation. The effects of various parameters including makeup water quality, salt formation, NH3 and CO2 evaporation mass transfer coefficients, heat load and operating temperatures were investigated. The results indicate that stripping of CO2 and NH3 in the cooling tower can significantly affect the cooling loop pH. x viii The model was also used to determine the rate of fouling in the condenser. The results indicate that the fouling rate of MWW as makeup water is significantly higher than that expected with fresh water, and tertiary treatment of MWW such as nitrification and/or softening can significantly reduce the fouling potential. Finally, the rate of fouling obtained from this study was integrated into the existing cost model developed earlier (at Illinois Institute of Technology) to perform the overall economic analysis. The results show that the use of municipal wastewater (MWW) to replace freshwater as makeup for the recirculating cooling loops of thermoelectric power plants is economically viable when tertiary treatments such as nitrification or softening are applied. Among various treatment strategies studied, nitrification of MWW has the lowest cost of 0.29 $/m3 for utilization in a 550 MW power plant. Furthermore, it was concluded that utilization of secondary treated municipal wastewater (MWW) without tertiary treatments such as nitrification or softening is not economically viable due to its significant fouling costs.
PH.D in Chemical Engineering, December 2013
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- Title
- CREDIT DEFAULT SWAP SPREAD FORECASTING USING THE LINEAR BAYESIAN RANDOM COEFFICIENTS MODEL WITH BALANCED PANELS
- Creator
- Arifi, Imir
- Date
- 2014, 2014-05
- Description
-
This study (thesis) predicts out of sample one to five year quarterly credit default swap spread curves for subsets of a population comprised...
Show moreThis study (thesis) predicts out of sample one to five year quarterly credit default swap spread curves for subsets of a population comprised of 308 companies via the linear Bayesian Random Coefficient Model (RMC) with balanced panel construction, capturing over 80% of reference entities with liquid CDS term structures. The use of scoring, structural and reduced form model variations generates credit spread tenure points and curves at the company level. The Altman Z-score and classic Merton structural framework explain too little of the credit default swap spreads out of sample. However, The Merton structural framework works well in predicting out of sample credit default swap spreads when modified by deriving the implied leverage ratio via market spreads. The widely used, Bloomberg implemented, JPMorgan 2001(CDSW) model works well for the period the study covers. The Bayesian Random Coefficients model explains 87% of observed credit default swap spreads one quarter out of sample, substantially exceeding any published research on the credit spread forecasting subject.
PH.D in Management Science, May 2014
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- Title
- The Effect of Salmonella Enteritidis on the Thermal Properties of Egg Albumen and Yolk
- Creator
- Chadha, Isha
- Date
- 2011-11-27, 2011-12
- Description
-
Salmonella-inoculated and uninoculated fresh eggs were microwave processed to achieve pasteurization. However, quality degradation was...
Show moreSalmonella-inoculated and uninoculated fresh eggs were microwave processed to achieve pasteurization. However, quality degradation was observed in the albumen of inoculated eggs but not in the uninoculated eggs although the processing was the same. Previous work showed that dielectric properties of egg albumen and yolk do not change in the presence of the bacteria. A new hypothesis was therefore proposed that heat capacity is affected by its presence. If an egg has a lowered heat capacity it will become hotter for a given amount of microwave energy input than eggs having normal heat capacities. The goal of the experiments was to determine whether Salmonella at varying concentrations and different incubation times affects the temperature-dependent thermal properties of egg albumen and yolk during in-shell growth. Although the main concern was Salmonella’s effect on the heat capacity of albumen, the equipment used could measure thermal conductivity as well and measurements on yolk were included for completeness. The thermal properties of both egg albumen and yolk were measured by the KD2 Pro thermal properties analyzer (Decagon Instruments, Pullman, WA) via the supplied 30 mm dual-needle sensor. Variables were temperature (7oC, 30oC, 40oC, 50oC, 55oC and 60oC), bacterial inoculum (0, 103, 106, 108 cfu/ml) and incubation time (0 or 30 hours). The measurements showed no significant difference in thermal properties between inoculated and uninoculated samples of egg albumen and yolk regardless of change in temperature, bacterial concentration and incubation period. The absence of an effect on either the dielectric (previous study) or thermal (present study) parameters by the presence of Salmonella leaves unexplained the quality differences between similarly processed inoculated and uninoculated eggs. A biochemical explanation based on the interaction between metabolic byproducts and egg proteins, affecting how they denature, is a topic for future research.
M.S. in Food Safety and Technology, December 2011
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- Title
- LAKESHORE CITY: A PROPOSAL FOR SOCIAL SUSTAINABILITY
- Creator
- Karpuzi, Isida
- Date
- 2013-04-25, 2013-05
- Description
-
After the collapse of the steel industry, the US Steel South Works plant left behind a vacant 600-acre area of lakefront land and thousands of...
Show moreAfter the collapse of the steel industry, the US Steel South Works plant left behind a vacant 600-acre area of lakefront land and thousands of unemployed workers that had inhabited the adjacent neighborhood of South Chicago. This thesis proposes the revitalization of this abandoned area through the development of a new community called Lakeshore City. The design of the new city is informed by the social and economic issues that have kept South Chicago in a poor condition since the closing of the mill and it is based on the solutions to those issues. Through adding diversified program, enhancing connectivity, and encouraging human interaction, Lakeshore City attempts to create a contemporary and socially sustainable living environment that can bring new prosperity to its surrounding neighborhood.
M.S. in Architecture, May 2013
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- Title
- Investigation of the service record and explosion hazard of chemical fire extinguishers
- Creator
- Kimball, Norman F
- Date
- 2009, 1917
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationofs00kimb
Thesis (B.S.)--Armour Institute of Technology
- Title
- Investigation of special steels
- Creator
- Andrews, E. E., Winser, R. A.
- Date
- 2009, 1908
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationofs00andr
Thesis (B.S.)--Armour Institute of Technology
- Title
- Investigations with recommendations of power and power costs in plant no. 2, Falls Creek Sand and Stone Co.
- Creator
- Ambrose, R. B.
- Date
- 2009, 1921
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationswi00ambr
Thesis (B.S.)--Armour Institute of Technology
- Title
- Investigation of the relative stability of vertical back and battered back dam sections
- Creator
- Geisler, R.j, Clark, R.b.
- Date
- 2009, 1912
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationofr00geis
Thesis (B.S.)--Armour Institute of Technology
- Title
- Investigation of time of combustion in a gas engine cylinder
- Creator
- Enander, E. H., Gaylor, W. S.
- Date
- 2009, 1906
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationoft00enan
Thesis (B.S.)--Armour Institute of Technology
- Title
- An investigation of the various properties of sand as affecting its use in concrete and mortar
- Creator
- Altman, Eugene E
- Date
- 2009, 1916
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationofv00altm
Thesis (B.S.)--Armour Institute of Technology;Bibliography: leaf 70
- Title
- An investigation of the tar by-product of the water gas industry
- Creator
- Harper, Robert B., Fash, Ralph H.
- Date
- 2009, 1905
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationoft00harp
Thesis (B.S.)--Armour Institute of Technology
- Title
- THE DEVELOPMENT OF AN INSTRUMENT TO EVALUATE TEACHERS’ CONCEPTS ABOUT NATURE OF MATHEMATICAL KNOWLEDGE
- Creator
- Kean, Lesa L.
- Date
- 2012-12-10, 2012-12
- Description
-
While there does seem to be widespread consensus that teachers’ beliefs and concepts influence the way they teach, even the most recent...
Show moreWhile there does seem to be widespread consensus that teachers’ beliefs and concepts influence the way they teach, even the most recent international studies suggest that research-based evidence for this consensus is limited. In an effort to enlarge and enhance the pool of evidence that shows specific relationships between teacher beliefs and practice, the present author undertook to write an attitude survey and interview protocol that identifies and distinguishes teachers’ concepts on eight different aspects of NOMK. Such a survey seems to be a natural first step to providing evidence for the larger question of which beliefs correlate to what teacher behaviors. Eight NOMK aspects were identified and defined based on a review of over 68 resources including twelve that contained an existing assessment addressing NOMK concepts. While superficial inspection of the assessments referenced may suggest that the best solution may be to use an existing assessment or to compile a list of items from these various assessments and use that to assess NOMK, the researcher suggests four major issues that would suggest otherwise. The items of the assessment and the assessment as a whole were validated through several steps. First, the author started with over 40 survey items, distributed evenly over her eight aspects and including both Likert-type and open-ended items. Second, the items were randomized and distributed to practicing mathematics teachers for their feedback. Third, the items were revised and sent back out to teachers for additional feedback. Fourth, the resulting survey was piloted with over 20 community college teachers. Fifth, their responses were coded, and the open-ended items were coded by xii rubric and confirmed by a second coder. Sixth, the survey was revised once again and piloted to another sample of 20 with similar analysis. Finally, she conducted several forms of qualitative and quantitative analysis to cull down the items to those that produced the most valid and reliable survey items set possible. The resulting survey addresses six of the eight aspects proposed by the researcher and includes both Likert-type and open-ended items intended to be confirmed and clarified through interview. The researcher suggests further research be done in order to design items that validly and reliably identify teachers’ concepts of NOMK on the remaining two aspects.
PH.D in Mathematics Education, December 2012
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- Title
- SIMULATION AND DEVELOPMENT OF A CLINICAL ANALYZER-BASED IMAGING SYSTEM
- Creator
- Majidi, Keivan
- Date
- 2013, 2013-12
- Description
-
The analyzer-based phase-sensitive X-ray imaging method (ABI) is emerging as a potential alternative to conventional radiography. ABI...
Show moreThe analyzer-based phase-sensitive X-ray imaging method (ABI) is emerging as a potential alternative to conventional radiography. ABI simultaneously generates a number of planar images containing information about scattering, refraction and absorption properties of the object. These parametric images are acquired by sampling the angular intensity profile (AIP) of an X-ray beam passing through the object at different positions of the analyzer crystal. Like many of the modern imaging techniques, ABI is a computed imaging method (meaning that the images are calculated from raw data). Therefore, the noise in ABI depends on the imaging conditions such as source flux, number of the analyzer positions, and the analyzer positions themselves as well as on the estimation method of the parameters. In the first part of this thesis, we use the Cramer-Rao lower bound to quantify the noise in ABI images and then investigate the effect of different analyzer-sampling strategies on this bound. The CRLB is the minimum bound for the variance of an unbiased estimator and defines the best noise performance that one can obtain regardless of which estimation method is used to estimate ABI parametric images. We will then use this bound to evaluate three ABI methods: Multiple-Image Radiography (MIR), Diffraction Enhanced Imaging (DEI) and Scatter Diffraction Enhanced Imaging (S-DEI). The proposed methodology can be used to evaluate any other ABI parametric image estimation technique. Synchrotron radiation has been the main source for experimental ABI and developing its methodologies, therefore the ABI application to clinical imaging has been very limited. It is inevitable to use conventional X-ray sources for ABI in order to utilize xii the technique in the clinical applications, however, due to the limited intensity of these sources and their finite source size, developing such systems is very challenging. In the second part of this thesis, we use computer simulations to understand the above challenges better. We measure the properties of this imaging system such as flux and point-spread function for various design parameters and discuss how to find an “optimal” setup based on these properties. The optimality of an imaging setup depends on the specific application that one wants to perform using the system; however, the results and discussions in this section layouts a design procedure for clinical ABI systems. In the last part of this thesis we review the steps we took in the Advanced X-ray Imaging Laboratory (AXIL) toward developing a clinical ABI system.
PH.D in Electrical Engineering, December 2013
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- Title
- GOTTA EAT TO LIVE, GOTTA STEAL TO EAT: THE INVESTIGATION OF SERIOUS DISRUPTIVE BEHAVIOR, TEMPERAMENT, AND EXECUTIVE DYSFUNCTION AMONG HOMELESS YOUTH
- Creator
- Kaszynski, Katie
- Date
- 2014, 2014-07
- Description
-
Background: Homeless youth are at risk for many adverse outcomes, including poor physical health, traumatic experiences, victimization, poor...
Show moreBackground: Homeless youth are at risk for many adverse outcomes, including poor physical health, traumatic experiences, victimization, poor academic achievement, cognitive deficits, psychopathology, and substance use. Research demonstrates that these individuals engage in substantial disruptive behavior (e.g., stealing, dealing drugs, breaking and entering, engaging in prostitution), which further increases their risk of negative outcomes. Individual factors, including innate temperament and executive functioning skills have been shown to relate to one another and be independently related to behavior problems, as evidenced by research investigating housed youth. Homeless youth are shown to exhibit poor effortful control, high distress, executive dysfunction, and substance abuse; factors of which have not been fully examined in relationship to persistent behavior problems as reflected in antisocial personality disorder (ASPD). Study Aim: The current study evaluated the association between temperament, executive functioning, and substance use disorders in their relation to the likelihood of meeting criteria for ASPD among homeless youth (ages 18-22). It was hypothesized that these variables would significantly relate to meeting criteria for ASPD in this population. Procedure: 87 homeless individuals (mean age = 19.27) who were residing at a homeless shelter at the time of the study (in Chicago or Los Angeles) participated over the course of two testing sessions. Each individual completed measures of ASPD and substance use disorders (MINI), temperament (ATQ), and executive functioning (D-KEFS), among other measures that are part of a larger studying conducted at University of Chicago Medical Center (UCMC). Results: Results suggested that temperament (specifically effortful control) executive dysfunction (specifically cognitive shifting), and substance use disorder (specifically substance abuse) were significantly related to the likelihood of a homeless individual meeting criteria for ASPD. Youth who showed poorer effortful control, better ability to shift attention between sets of information, and substance abuse were at a greater likelihood of meeting criteria for ASPD. Conclusions: These findings indicate that aspects of temperament, specific executive skills, and substance abuse are important variables in determining the likelihood of ASPD among a population of homeless individuals. Clinical implications, limitations, and suggestions for interventions are discussed.
Ph.D. in Psychology, July 2014
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