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Title: EFFECT OF ORGANIZATIONAL JUSTICE ON EMPLOYEE HEALTH
Creator: Cruz, Jaime L.
Date: 2013, 2013-05
Description: Although many studies in the justice literature have examined organizational justice and organizational outcomes, less research has been...
Show moreAlthough many studies in the justice literature have examined organizational justice and organizational outcomes, less research has been conducted on organizational justice and employee health. Specifically, this study examined the relationship between employees’ perceptions of organizational justice dimensions – distributive, interactional and procedural justice in relation to proximal health outcomes (i.e., general well-being, insomnia, emotional exhaustion, alcohol consumption and emotional eating). It was hypothesized that lower levels of perceived justice at work would be associated with worse health related outcomes. With the study’s sample size of 339, results partially supported the hypotheses. Explicitly, results indicated that lower perceptions of distributive and interactional justice were related to increased emotional exhaustion and poorer overall health assessments (general well-being) in employees. Additionally, procedural justice perceptions were found to interact with individuals’ use of heuristic devices in that those who were more inclined to use heuristic devices when making justice judgments displayed a significant relationship between procedural justice perceptions and certain health outcomes (i.e., emotional eating) while individuals less inclined to utilize heuristics did not display a significant relationship between the aforementioned justice and health measures. In sum, this study, provides a much needed starting point for organizational scholars to begin to address and understand the relationship between justice perceptions and health related outcomes at work.
PH.D in Psychology, May 2013
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Title: SMART GRID COORDINATION OF A CENTRALIZED POWER AND COOLING FOR AN URBAN COMMUNITY
Creator: Franco, Diego Pacheco
Date: 2016, 2016-05
Description: Because the world’s fossil fuel reserves are finite, it is essential to substantially improve the efficiency of all energy consumers. Heating,...
Show moreBecause the world’s fossil fuel reserves are finite, it is essential to substantially improve the efficiency of all energy consumers. Heating, ventilating and air conditioning (HVAC) accounts for 45% of energy consumption in residential buildings. Thus, this project studied and proposed solutions to improve the efficiency of such systems. The project begins with an analysis of a cooling system using electric chillers for a new hypothetical residential community in the Chicago area. Then, two new hybrid configurations were proposed: the utilization of electric and absorption chillers and then this system was augmented with a Thermal Energy Storage (TES) system. A simulation environment based on Matlab/Simulink®, using the concepts of Economic Model Predictive Control (EMPC) was developed to evaluate the performance of these configurations. The main benefits found were the increasing energy efficiency, the environmental impacts reduction and a reduction of more than 70% in operating costs (in some cases, profit was generated).
M.S. in Chemical Engineering, May 2016
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Title: Formation of aluminium nitride
Creator: Rudd, E. B., Veit, L. L.
Date: 2009, 1921
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/formationofalumi00rudd
Thesis (B.S.)--Armour Institute of Technology

Title: The floor distribution of water from automatic sprinkler heads
Creator: Goppelsroeder, Roy A. C., Peterson, Leonard A, Grasse, C. A.
Date: 2009, 1916
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/floordistributio00gopp
Thesis (B.S.)--Armour Institute of Technology

Title: Forces set up in a conductor by a current pinch effect
Creator: Mastro-valerio, Giuseppe
Date: 2009, 1909
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/forcessetupincon00mast
Thesis (B.S.)--Armour Institute of Technology

Title: Floor distribution of standard automatic sprinkler heads
Creator: Kula, J. S., Foschinbaur, L. A., Schreiner, R. F.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/floordistributio00kula
Thesis (B.S.)--Armour Institute of Technology

Title: Forest Canon Reservoir
Creator: Hayden, Albert, Jr, Hayden, Julian
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/forestcanonreser00hayd
Thesis (B.S.)--Armour Institute of Technology; Bibliography : leaf 8

Title: EMBEDDED SYSTEM DESIGN FOR TRAFFIC SIGN RECOGNITION USING MACHINE LEARNING ALGORITHMS
Creator: Han, Yan
Date: 2016, 2016-12
Description: Traffic sign recognition system, taken as an important component of an intelligent vehicle system, has been an active research area and it has...
Show moreTraffic sign recognition system, taken as an important component of an intelligent vehicle system, has been an active research area and it has been investigated vigorously in the last decade. It is an important step for introducing intelligent vehicles into the current road transportation systems. Based on image processing and machine learning technologies, TSR systems are being developed cautiously by many manufacturers and have been set up on vehicles as part of a driving assistant system in recent years. Traffic signs are designed and placed in locations to be easily identified from its surroundings by human eyes. Hence, an intelligent system that can identify these signs as good as a human, needs to address a lot of challenges. Here, ―good‖ can be interpreted as accurate and fast. Therefore, developing a reliable, real-time and robust TSR system is the main motivation for this dissertation. Multiple TSR system approaches based on computer vision and machine learning technologies are introduced and they are implemented on different hardware platforms. Proposed TSR algorithms are comprised of two parts: sign detection based on color and shape analysis and sign classification based on machine learning technologies including nearest neighbor search, support vector machine and deep neural networks. Target hardware platforms include Xilinx ZedBoard FPGA and NVIDIA Jetson TX1 that provides GPU acceleration. Overall, based on a well-known benchmark suite, 96% detection accuracy is achieved while executing at 1.6 frames per seconds on the GPU board.
Ph.D. in Computer Engineering, December 2016
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Title: INFLUENCE OF OWNER-ORGANIZATION IMPRESSION AND CONTRACT FRAMING ON CONSTRUCTION CONTRACTORS' RISK PERCEPTIONS
Creator: Hanioglu, Mehmet Nihat
Date: 2014, 2014-12
Description: In a construction project, it is generally accepted that the contractor's perceived risk is the main factor in determining what is to be...
Show moreIn a construction project, it is generally accepted that the contractor's perceived risk is the main factor in determining what is to be proposed as the project cost and duration. Both the owner-organization and the contractor are aware of the existing risks and the owner-organizations tend to mitigate the existing risks by using the construction contract. It is hypothesized that the contractor’s initial impression of the owner-organization is a factor in the contractor’s perception of risk. It is further hypothesized that the initial impression is influenced by the content and context of the construction bid documents, which further influences the perceived risk and the bid strategy. The goal is to investigate the factors that influence contractors' impression of the owner-organization and to study the effects of contract document language and content in the impression formation process and subsequent development of a bid strategy. By better understanding the factors and relationships that influence impression formation and risk perceptions, it is expected that substantial time, money and unnecessary contention between these parties can be eliminated.
Ph.D. in Civil Engineering, December 2014
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Title: CYCLIC THERMAL TREATMENT
Creator: Gu, Sijie
Date: 2015, 2015-12
Description: Cyclic thermal treatment has the potential to improve energy efficiency of thermal processing. It has been shown that in some cases, the...
Show moreCyclic thermal treatment has the potential to improve energy efficiency of thermal processing. It has been shown that in some cases, the productivity was enhanced by the cyclic thermal treatment operation. In order to investigate the cyclic thermal treatment effect, Copper-Nickel interdiffusion couples were investigated. When the Cu-Ni interdiffusion couple showed positive results, the cyclic thermal treatment was applied to pack carburization and gas carburization of steel. The Cu-Ni interdiffusion couples were annealed with different time-temperature profiles for 5 days. There are three types of time-temperature profile; isothermal, symmetric, and asymmetric cyclic thermal treatment. After thermal treatment, concentration-distance profiles were. Based on the concentration-distance profile, the interdiffusion coefficients of different time-temperature profiles were calculated. The interdiffusion coefficient of the diffusion couple with a ramp rate of 1°C/min had a higher diffusion coefficient than that of the diffusion couple annealed isothermally at the equivalent temperature, 863°C, which means that cyclic thermal treatment has the effect of accelerating diffusion. When the ramp rate was 5ºC/min interdiffusion coefficients were higher than that of the diffusion couple annealed isothermally at the maximum temperature. However, when the ramp rate was increased to 10°C/min, the diffusion coefficient decreased to almost the same as the interdiffusion coefficient of the diffusion couple at the equivalent temperature. After achieving a promising result for the Cu-Ni diffusion couples, we expanded the cyclic thermal treatment to carburizing. The temperature range for cyclic pack carburization was 850° to 950°C. Increasing the cyclic ramp rate resulted in an increase in the case depth. Due to the setup of the pack carburization, the maximum cooling rate achievable is 5°C/min. In order to reach a higher ramp rate, an induction heating gas carburization system was setup. The temperature range for the cyclic induction heat gas carburization was 850°C to 950°C. For the cyclic induction heat gas carburization with increase in ramp rate, the case depth increased. The sample induction gas carburized at a ramp rate of 20°C/min had a deeper case depth than the sample induction gas carburized isothermally at 904.4°C, the equivalent temperature. The first test showed the sample induction gas carburized with a ramp rate of 20°C/min had a deeper case depth than the sample induction gas carburized isothermally at 950° C. With this we draw the conclusion that the cyclic induction gas carburization can achieve a deeper case depth than the isothermal at equivalent temperature induction gas carburization.
Ph.D. in Materials Science and Engineering, December 2015
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Title: POWER GRID VERIFICATION ON CLOUD
Creator: Gupte, Naval
Date: 2016, 2016-05
Description: Reliability and performance of modern ICs is becoming increasingly susceptible to supply voltage variations. Increased demand for low voltage...
Show moreReliability and performance of modern ICs is becoming increasingly susceptible to supply voltage variations. Increased demand for low voltage integrated circuits has made power grid analysis extremely critical and indispensable in modern design flows. Efficient validation of on-chip power distribution network is computationally demanding because of increasing grid sizes. Power grid simulation is critical for analysis and verification of power supply noises for robust and reliable IC designs. Computational demands to simulate power grids for ICs with increasing complexity is never-ending. Cloud computing platforms can be leveraged to mitigate costs associated with making these resources available. However, since simulation data usually contains sensitive design information, simulating on third-party platforms lead to major security concerns. In this study, we propose a framework for secure power grid simulation on Cloud. A transformation algorithm to hide current excitations is presented, while still allowing a majority of computations to be completed on Cloud. We employ multiple compression strategies to significantly reduce communication and storage overheads. Experiments show that our framework can achieve similar turn-around time as an insecure simulator on Cloud, while securing current excitations and output voltage vectors with reasonable communication and computational overheads. Vectorless technique to grid verification estimates worst-case voltage noises without detailed enumeration of load current excitations. We study voltage noise assessment in RLC models of VDD and GND networks in integrated power grids. Abstract grid model is utilized to abbreviate runtime, while transient constraints capture transitory circuit behaviour. Heuristics are employed to extract constraints that restrict power consumption profiles to realistic scenarios. Multiple linear programming problems are formulated to evaluate bounds on voltage overshoots and undershoots. We propose ways to mitigate storage and computational requirements on processing resources, enabling users to deploy computations on economical Cloud Computing platforms. Recommended solution is parallelizable, thereby reducing the overall verification time. Data compression is applied to fully exploit the compute capabilities of contemporary processors for higher throughputs. Experimental results suggest that the proposed technique is practical and scalable for industrial grids.
Ph.D. in Electrical Engineering, May 2016
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Title: PERFECTIONISM AS A MODERATOR OF ASSOCIATIONS BETWEEN BODY DISSATISFACATION AND DISORDERED EATING: AN ECOLOGICAL MOMENTARY ASSESSMENT STUDY
Creator: Hansen, Meghan A.
Date: 2017, 2017-07
Description: Disordered eating attitudes and behavioral urges are prevalent in community samples and contribute to numerous negative physical and...
Show moreDisordered eating attitudes and behavioral urges are prevalent in community samples and contribute to numerous negative physical and psychological outcomes. Using an ecological momentary assessment, this study examines how body dissatisfaction, perfectionism, and disordered eating relate to one another. Over the course of one week, women (n=49) with disordered eating completed multiple daily ratings of body dissatisfaction and disordered eating attitudes, urges and behaviors. Multilevel model analyses were used to test study hypotheses that; (1) body dissatisfaction prospectively predicts disordered eating attitudes and urges; and (2) perfectionism moderates the associations between body dissatisfaction and subsequent disordered eating attitudes and behaviors, such that individuals higher in perfectionism will report stronger associations between these variables. Results indicate that, in this sample, greater body dissatisfaction does not predict disordered eating attitudes, urges or behaviors. However, the interaction between increased body dissatisfaction and perfectionism predicted subsequent disordered eating attitudes and behavioral urges, but did not predict engagement in eating disorder behaviors. Results have important clinical and treatment implications for including perfectionism in the treatment of eating disorders.
Ph.D. in Psychology, July 2017
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Title: DEPRESSION AND ATTRIBUTIONS FOR DISTRESS
Creator: Hanson, Bjorn J.
Date: 2013, 2013-07
Description: Distress caused by depressive symptoms includes both direct and mediated pathways. Attributions for distress in individuals suffering from...
Show moreDistress caused by depressive symptoms includes both direct and mediated pathways. Attributions for distress in individuals suffering from depressive symptoms represent indirect pathways that have a high potential to be modified by psychotherapeutic interventions; however, little research has focused on the content of these attributions. This study provides the first quantitative measurement of this reasons-for-distress paradigm. Specifically, we aim to describe the frequencies, intensities, and co-occurrence patterns of attributions for distress, as well as distinguish the attributions for distress paradigm from previous attributions for depression research. Furthermore, we seek to demonstrate the accuracy of an illness behavior model for conceptualizing distress caused by depressive symptoms by differentiating symptom severity from symptom distress. In addition to quantifying attributions for distress, this study also extends previous research regarding rumination, the severity of distress caused by cognitive and vegetative symptoms of depression, and the co-occurrence of specific symptoms and specific reasons for distress. Individuals currently suffering from depressive symptoms were recruited from web-based advertisements to participate in this cross-sectional, online self-report study. A total of 204 individuals qualified for the study and completed some portion of the Reasons for Distress Questionnaire-Depression (RDQ-D). Results demonstrated that all reasons provided as part of the RDQ-D represented common attributions for distress in depressed individuals. Reasons related to personalized reasons for distress (Other), long-term outcomes (Long-term Consequences), productivity impairment (Work and Productivity Impairment), and x existential distress (Lack of Purpose or Meaning) were rated as significantly more distressing when compared with all reasons for distress. Cluster analysis suggested that certain reasons tended to co-occur and that some attributions for distress are nearly universal amongst individuals suffering from significant depressive symptoms. The reason-for-distress paradigm was demonstrated to be related to, yet distinct from, the reason-for-depression paradigm (Addis, Truax, & Jacobson, 1995). Distress ratings were also found to be moderately positively correlated with some depressive symptoms, but not others, providing support for an illness behavior conceptualization of distress severity in depression. Expanding on prior research, results showed that rumination was equally distressing and frequent across gender. Also, cognitive/affective symptoms of depression were rated as more distressing than vegetative symptoms of depression. Additionally, participants demonstrated the capacity to endorse specific reasons for distress in association with specific symptoms. As predicted, the existential reason for distress Lack of Purpose or Meaning was endorsed more frequently in relation to cognitive/affective symptoms of depression as compared to vegetative symptoms of depression. By focusing on specific symptoms of depression, the RDQ-D provides a clinical assessment that has the ability to identify specific unhelpful responses to symptoms that may be causing distress in addition to that inherent in the experience of the symptom. These unhelpful responses can then be included in case conceptualization, treatment planning, and intervention selection.
PH.D in Psychology, July 2013
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Title: COMPUTER AIDED DIAGNOSIS IN MAMMOGRAPHY WITH CONTENT-BASED IMAGE RETRIEVAL
Creator: Jing, Hao
Date: 2011-11, 2011-12
Description: Computer-aided diagnosis (CAD) for breast cancer, a common form of cancer in women, has been an active research area. This work aims to...
Show moreComputer-aided diagnosis (CAD) for breast cancer, a common form of cancer in women, has been an active research area. This work aims to investigate and develop CAD techniques for clustered microcalcifications (MCCs), which can be an important early sign of breast cancer. The contributions of this work include development of a database of cancer cases and algorithms for detection and classification of MCCs. First, a database consisting of a large number of cases is built from different sources. To support the merging of cases from different data sources, a feature comparison study is conducted between mammograms from screen film and full field digital mammography (FFDM) systems. It is demonstrated that the features extracted from film and FFDM are highly correlated and there is no adverse effect on a CAD task of classification when used together. Second, a spatial point process (SPP) approach is proposed to exploit the spatial distribution among different MCs in a mammogram directly during the detection process. This is different from the conventional approach in which detection algorithms are employed to first identify individual MCs in a mammogram, which are subsequently grouped into clusters by a clustering algorithm. The performance of the proposed approach is demonstrated to be superior to an existing method based on the support vector machine (SVM). Third, in observation of the emerging of large databases from the picture archiving and communication (PAC) systems in the clinics, a retrieval driven approach is proposed for classification of MCCs. In this approach, for a case to be diagnosed (i.e., query), a set of similar cases is retrieved from a database and subsequently is used to train xii an adaptive classifier specifically for the query case using the technique of logistic regression. The proposed approach is demonstrated to lead to significant improvement in classification accuracy. Moreover, the proposed adaptive classification approach is further developed using regularization techniques, where a prior is first derived from a baseline classifier and then used to regularize the adaptive classifier trained with the retrieved cases. The regularized adaptive classifier can be more computationally efficient, and is demonstrated to achieve further improvement in performance.
Ph.D. in Electrical Engineering, December 2011
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Title: INTERACTION OF DAIRY BASED PROTEIN WITH PHENOLIC ANTIOXIDANT OF STRAWBERRY POWDER
Creator: Feng, Haoshi
Date: 2012-05-04, 2012-05
Description: Fruits contain an abundant amount of polyphenolic compounds that have antioxidant properties. These compounds have shown the ability of...
Show moreFruits contain an abundant amount of polyphenolic compounds that have antioxidant properties. These compounds have shown the ability of reducing the risk of major degenerative diseases, relief from allergies/asthma, weight loss and improved circulation. Dairy proteins have numerous benefits as enhancing muscle formation, weight and blood pressure control, beneficial effect in bone and dental health and protection against toxins, bacteria, and viruses. The combination of both fruit and dairy in commercial or homemade mixtures, such as smoothies, is readily available and popular. But in fact, the interactions which happen between proteins and fruit antioxidants could affect the availability and potential activity of antioxidants. This thesis will focus on the interaction of dairy proteins with antioxidant from freeze dried strawberry and measure the availability of the antioxidant capacity. Freeze dried strawberry powder at different concentrations (1.64%, 3.28% and 6.56%) was mixed with four types of proteins at different concentration to demonstrate the interaction over a range. The proteins used were skim milk powder (6.89%), whey from bovine milk (0.51%), casein from bovine milk (2.04%), and albumin from bovine serum (2.55%). The antioxidant content was measured by several analytical techniques using LCMS/MS, Oxygen Radical Absorbance Capacity (ORAC) assay and Folin-Ciocalteu assay. SDS-PAGE was used to examine the change of protein molecular weight before and after the reactions. The binding interaction resulted in significantly reduced ORAC and Folin- Ciocalteu assay values compared to the respective non-protein strawberry mixtures (P<0.001 and P<0.05). The SDS-PAGE images between protein strawberry mixtures and non-protein strawberry mixtures showed similar results. The (+)-catechin, cyanidin-3-O glucoside, pelargonidin-3-O-glucoside and kaempferol-3-coumaroylglucoside content were significantly reduced when comparing skim milk based strawberry powder mixtures and non-protein strawberry mixtures (P<0.05). This research indicates the binding interaction between dairy protein and freeze dried strawberry powder reduces the antioxidant activity of the freeze dried strawberry powder.
M.S. in Food Safety and Technology, May 2012
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Title: MEASUREMENT OF INTRARETINAL NITRIC OXIDE IN EARLY DIABETIC RETINOPATHY
Creator: Guthrie, Micah
Date: 2014, 2014-12
Description: Diabetic retinopathy (DR) is the most frequent cause of new cases of blindness among adults aged 20-74 years. Nearly all patients with Type 1...
Show moreDiabetic retinopathy (DR) is the most frequent cause of new cases of blindness among adults aged 20-74 years. Nearly all patients with Type 1 diabetes and greater than 60% of patients with Type 2 diabetes will develop retinopathy within the rst two decades of the disease. Nitric oxide (NO) has been shown to play a role in the progression of DR, contributing to neuronal dysfunction and the breakdown of the blood-retina barrier early stages of the disease. The objective of the current study was to investigate the changes in intraretinal NO levels in early DR. To accomplish this, a dual NO/electroretinogram (ERG) electrode was developed to make the rst direct measurements of NO concentration throughout the in vivo retina. These electrodes were validated in an in vivo animal model by comparing control recordings to those taken after injection of the broad spectrum nitric oxide synthase (NOS) inhibitor L-NG-Nitroarginine methyl ester (L-NAME). Control NO pro les showed high levels of NO in the photoreceptor layer with localized areas of increased NO in the amacrine/ganglion cell layer. L-NAME NO pro les showed substantially reduced NO in the retina, indicating that the electrodes were measuring actual NO. The electrodes were then used to record NO pro les from the retinas of rats made diabetic with streptozotocin (STZ). The recordings were obtained three weeks after injection of STZ. Blood glucose levels were also monitored in order to correlate the blood glucose level with intraretinal NO concentration. It was found that mild diabetic rats (blood glucose 250-400 mg/dL) had higherthan- control levels of NO throughout their retinas. Severe diabetics (500-600 mg/dL) had lower-than-control levels, while moderate diabetics (400-500 mg/dL) did not have signi cantly di erent NO levels than controls. The NO pro les from the severe diabetics were very similar to L-NAME pro les, indicating that NOS production may be abnormal in severe diabetics. It was also found that intraretinal NO concentration was inversely correlated with the blood glucose of diabetic rats. To determine if the changes in NO seen in diabetic rats were due to direct tissue exposure to high glucose, NO pro les were also recorded from rats acutely injected with glucose solution to achieve similar levels of hyperglycemia. No changes in NO levels were seen in the retinas of these acute hyperglycemic rats, indicating that there are other factors besides high glucose contributing to the NO changes in DR. The results show that there is not a simple increase in NO as severity of diabetes increases and highlight the importance of being able to make measurements of bioavailable NO in retinal tissue. The electrodes were able to detect clear di erences in experimental DR, indicating their utility in investigating NO changes in the early stages of the disease. Future work with the electrodes needs to be performed to investigate the mechanisms of NO changes in DR in order to develop potential treatments which could mitigate the damage at an early stage before vision loss occurs.
M.S. in Biomedical Engineering, December 2014
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Title: HIV-RELATED TRAUMA AND ANTIRETROVIRAL ADHERENCE: THE EFFECTS OF PERSONAL RESOURCES
Creator: Guy, Arryn A.
Date: 2017, 2017-05
Description: Suboptimal adherence to antiretroviral therapy (ART) can interfere with virologic suppression and increase risk of developing drug-resistant...
Show moreSuboptimal adherence to antiretroviral therapy (ART) can interfere with virologic suppression and increase risk of developing drug-resistant strains of the virus. People living with HIV (PLH) have difficulty complying with ART—a treatment regimen that is unforgiving of non-adherence—in large part because this population is at higher risk for stressors, including experiencing their HIV diagnosis as a traumatic event (e.g., Boarts et al., 2006; Theuninck, Lake, & Gibson, 2010). Perceived social support and coping are contextual and changeable factors that can be focused on in interventions to improve treatment adherence. This study aimed to confirm that more perceived social support is related to optimal treatment adherence in PLH who experienced HIV-related trauma, through bolstering coping strategies, namely, emotion-focused coping strategies like positive reappraisal and emotional social support seeking, and problem-focused coping related to managing ART (i.e., active coping). Participants were 62 young adults living with HIV recruited from a local HIV clinic. Participants were assessed for experiencing their HIV diagnosis as a traumatic event, perceived social support, coping, and medication adherence. Positive reappraisal, emotional support seeking, and active coping strategies did not mediate the relation between perceived social support and adherence, however, active coping had a statistically significant effect on adherence when controlling for other hypothesized mediators in the model. This finding has practical significance for clinicians in that it suggests active coping plays a more direct role in improving treatment adherence than emotional support seeking and positive reappraisal coping strategies.
M.S. in Psychology, May 2017
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Title: TOWARD A NATURAL GENETIC/EVOLUTIONARY ALGORITHM FOR MULTIOBJECTIVE OPTIMIZATION
Creator: Ramasamy, Hariharane
Date: 2013, 2013-05
Description: Practical optimization problems often have multiple objectives, which are likely to conflict with each other, and have more than one optimal...
Show morePractical optimization problems often have multiple objectives, which are likely to conflict with each other, and have more than one optimal solution representing the best trade-offs among the competing objectives. Genetic algorithms, which optimize by repeatedly applying genetic operators to a population of possible solutions, have been used recently in multiobjective optimization, but often converge to a single solution that is not necessarily optimal due to lack of diversity in the population. Current multiobjective genetic and other evolutionary methods prevent this premature convergence by promoting new members that are dissimilar in parameter or objective space. A distance measure, which calculates similarities among the members in either objective or parameter space, is used to degrade the fitness of solutions when they are crowded in a small region. This process forces the algorithm to find new but distinct trade-off points in the objective or parameter space, but is computationally expensive. As the number of objectives or parameters increases, the methods fail to scale up and they deviate from the motivating concept of the genetic algorithm—natural evolution. We extend the standard genetic algorithm through two simple, yet powerful, changes motivated by natural evolution. In the first method, the algorithm, at each step, randomly or sequentially chooses one of the objectives for optimization; hence the method is called sequential extended genetic algorithm (SEGA). In the second method, a population is maintained for each objective, and crossover is performed selecting parents from across populations. This method is called parallel extended genetic algorithm (PEGA). We applied these methods to test problems from the literature, and to two well known problems, protein folding and multiple knapsack. We discovered our methods found better trade-off solutions than current multiobjective methods, without increasing computational complexity of genetic algorithms.
PH.D in Computer Science, May 2013
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Title: EFFICACY OF PULSED LIGHT TECHNOLOGY FOR THE INACTIVATION OF SALMONELLA ENTERITIDIS PT 30 ON ALMOND KERNEL SURFACE
Creator: Harguindeguy, Maite
Date: 2016, 2016-05
Description: Almond surfaces can be contaminated with pathogens such as Salmonella. Traditional thermal processing technologies used for inactivation of...
Show moreAlmond surfaces can be contaminated with pathogens such as Salmonella. Traditional thermal processing technologies used for inactivation of Salmonella on almonds can adversely impact the quality. Therefore, there is a need to investigate the efficacy of alternative technologies for inactivation of Salmonella on almonds without adversely affecting the quality. Pulsed light, a novel technology, can potentially be used to achieve this. Therefore, this study evaluated the efficacy of three pulsed light systems (operating at 1.8, 3, or 100 Hz) under various electrical input powers (1000, 1250 and 1500 W) and treatment times for inactivation of Salmonella Enteritidis PT 30 on almond surfaces. More than 4-log reduction was achieved at different treatment conditions for each of the control units. For instance, a 160 s treatment at 1500 W (100 Hz system) resulted in a 4.3 log CFU/almond reduction. Whereas, similar reductions were achieved in a shorter time with the lower frequency systems (1.8 or 3 Hz). Reductions of 4.6 and 5.9 log CFU/almond were achieved after 80 and 100 s treatment, respectively with the 1.8 Hz system (1250 W). Similarly, a 100 s treatment with the 3 Hz system (1000 W) resulted in a reduction of 4.7 log CFU/almond. Statistical analysis showed that the effect of equipment, treatment time, and electrical power input were significant (p<0.05). The D-values of 1.8, 3, and 100 Hz systems were 0.24, 0.53 and 0.73 min, respectively at 1500 W. In general, lower frequencies resulted in increased inactivation in shorter time. This can be attributed to the higher instantaneous power at lower frequencies. Similar trends were observed at other electrical input powers. The D-values found using pulsed light treatment are lower than the conventional dry heat treatment ones. Also, minimal color change was observed for treated almonds. These results indicate that pulsed light is efficacious for decontaminating almond surfaces within a relatively short time.
M.S. in Food Process Engineering, May 2016
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Title: Grinnell variable pressure alarm valve
Creator: Eyers, Walter, Thomson, F. L.
Date: 2009, 1908
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/grinnellvariable00eyer
Thesis (B.S.)--Armour Institute of Technology, 1908 B.S. in Fire Protection Engineering,...
Show morehttp://www.archive.org/details/grinnellvariable00eyer
Thesis (B.S.)--Armour Institute of Technology, 1908 B.S. in Fire Protection Engineering, 1908
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