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- Title
- A NUMERICAL-METHOD FOR DETERMINING OPTIMAL PARAMETER VALUES IN FORCED PERIODIC OPERATION
- Creator
- Ozgulsen, F., Adomaitis, R. A., Cinar, A.
- Date
- 1992-02
- Publisher
- PERGAMON-ELSEVIER SCIENCE LTD
- Description
-
A numerical approach for determining values of forcing parameters which maximize performance of a periodically forced system is described....
Show moreA numerical approach for determining values of forcing parameters which maximize performance of a periodically forced system is described. Periodic solutions of the system equations plus a differential form of the time-average performance measure are computed with a shooting algorithm. A nonlinear programming package is used to solve the optimization problem. The algorithm is applied to ethylene oxidation process, using the model of a continuous stirred-tank reactor (CSTR).
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- Title
- B-SPLINE BASED ROBUST FORMULATION IN TOPOLOGY OPTIMIZATION
- Creator
- Gu, Yu
- Date
- 2014, 2014-12
- Description
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In this thesis, we extend the B-spline based density representation to robust topology optimization. The B-spline based representation has...
Show moreIn this thesis, we extend the B-spline based density representation to robust topology optimization. The B-spline based representation has been shown to have the ability of preventing checker-boards. With separate analysis and design mesh, the B-spline based filter is also competitive on computation storage compared with usual density filter. However, the current B-spline based representation is not robust where gray transitions exist. The recent proposed robust formulation highlights the manufacturability that simulates under- or over- etching designs compared with intermediate design. The robustness is demonstrated through three test cases. The minimum length control for quadratic B-splines is analytically derived with respect to knot span size and threshold. Our study about the characteristics of rectangular domain of B-spline based representation, shows that the optimized designs are comparable to those by density filter.
M.S. in Mechanical and Aerospace Engineering, December 2014
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- Title
- Transmission efficiencies of belting
- Creator
- Marks, Robert Edward
- Date
- 2009, 1919
- Publisher
- Armour Institute of Technology
- Description
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http://www.archive.org/details/transmissioneffi00mark
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 29
- Title
- ENVIRONMENTAL PERFORMANCE VS. FINANCIAL PERFORMANCE, MARKET INEFFICIENCY AND INVESTMENTS
- Creator
- He, Chaohua
- Date
- 2014, 2014-07
- Description
-
It is challenging to de ne corporate environmental performance or corporate nancial performance. In this study, a company is considered to...
Show moreIt is challenging to de ne corporate environmental performance or corporate nancial performance. In this study, a company is considered to have good environmental performance (namely, be green, environment-friendly or environmentally responsible) if it is among the Top 100 of the 500 US greenest companies ranked by Newsweek, or has environmental strength(s) and no environmental concern in terms of the KLD ratings. A company is regarded to have good nancial performance if it has a high raw return, Sharpe ratio, and excess (or abnormal) return over various benchmarks. Preference will be given to excess return estimated using the Carhart four-factor model [14]. A previous published longitudinal study, co-authored with my advisor [13], unveils that: 1) environmentally responsible companies tend to experience signi cantly positive abnormal performance in the long horizon (e.g. from the fourth to seventh year after being selected); 2) the value-adding e ect and the market's upward price adjustments on undervalued intangible environmental strength(s) might have resulted in the long-term outperformance. Would environmentally responsible companies still outperform during shorter horizons, such as the event period of an environmental disclosure? Using event study methodologies, this paper investigates market responses to independent Newsweek environmental disclosures by analyzing cross-sectional and time-series abnormal security returns. Results suggest that the Top 100 greenest companies tend to display signi cant abnormal returns within 4 days after a disclosure, and the signi cant abnormal returns generally persist for no more than 3 trade days. e.g., the Carhart four-factor abnormal return, with statistical signi cance, is averaged at 0.50% per day over the four disclosure events. The ndings are robust to di erentmodels of normal return, removal of outliers, elimination of confounding e ects, controlling for characteristic factors, and adjusting for cross-sectional correlation and volatility shift on test statistics using BMP-adjusted technology[56]. Signi cant abnormal returns over the event period may indicate ine ciency of the nancial market. Fama-Macbeth regressions further reveal that short-horizon abnormal returns could be explained by a spectrum of characteristic variables, green investing, arbitrage trading, and/or various psychological biases. Complementing the cited longitudinal study, a portfolio-level comparison reveals that an actively managed green portfolio outperforms an actively managed nongreen portfolio in terms of raw return and risk-adjusted measures such as Sharpe ratio, Jensen's alpha and Fama-French alpha in the long horizon. The results are robust to di erent portfolio weighting technologies and the consideration of turnover costs. In addition, the green portfolio's outperformance is driven by a bunch of small, aggressive and relatively inactive stocks that have better performance than the market predicts. No evidence shows that the ever-increasing demand on green securities leads to the green portfolio's outperformance, because green stocks are actually less actively traded. Panel regressions further indicate that long-horizon corporate economic performance positively correlates to historical corporate environmental performance.
Ph.D. in Management Science, July 2014
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- Title
- SUSTAINABLE, CONTROLLED, REACTION SYNTHESIS OF METALLIC WIRES AND STRIPS
- Creator
- Chen, Xin
- Date
- 2014, 2014-05
- Description
-
The main purpose of this work is to investigate bi and tri-metallic metal com- binations as initiators which require an ability to have a self...
Show moreThe main purpose of this work is to investigate bi and tri-metallic metal com- binations as initiators which require an ability to have a self-sustaining exothermic reaction. Through the reaction, the initiator should achieve a temperature in excess of 500 C when in contact with a thermally conducting surface. Also the initiator must be in the form of a exible wire or strip of the order of one millimeter radius. There are four phases in my MS research project. First was identifying the potential candidate compounds for exothermic reaction. During this phase, I wrote a program using Mathematicar (Appendix A) to calculate the adiabatic temperature resulting from the reaction of di erent binary or ternary elemental combinations. The calculation took into account the speci c heats and any enthalpies of transformation occurring between room temperature and the adiabatic temperature. Based on the results of this program several suitable compositions were selected from three hun- dred candidates. The second phase was determining a methodology to manufacture selfCpropagating thin strips or wires. We attempted several methods including plate rolling, wire twisting, mechanical coating, chemical coating, and powder metallurgy. We successfully obtained self-propagating thin metal strips and wires using powder metallurgy methods. In the third phase, a transparent reaction box was constructed in order to provide a protective atmosphere (Ar gas) and connect to a data acqui- sition system to obtain the reaction temperature, initiation temperature and video materials of reactions. In the last phase, the reacted samples were characterized using Scanning Electron Microscope (SEM), Backscattered Electron detector (BSE), X-ray Di raction (XRD), Di erential scanning calorimeter (DSC), etc.
M.S. in Mechanical, Materials, and Aerospace Engineering, May 2014
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- Title
- A MODEL OBJECT BASED SUPERVISORY EXPERT SYSTEM FOR FAULT TOLERANT CHEMICAL REACTOR CONTROL
- Creator
- Basila, M. R., Stefanek, G., Cinar, A.
- Date
- 1990-05
- Publisher
- PERGAMON-ELSEVIER SCIENCE LTD
- Description
-
An expert system for real-time control of chemical processes provides an environment for coordination of process fault diagnosis, assessment...
Show moreAn expert system for real-time control of chemical processes provides an environment for coordination of process fault diagnosis, assessment of process behavior, automated controller retuning and/or reconfiguration and consequently enables fault-tolerant process control. A supervisory expert system with object-based knowledge representation and heuristic (shallow) and model-based (deep) knowledge is presented. The expert system resides on a PC/386 and communicates with the control system developed in the form of control blocks residing on a PC/286. The prototype of the expert system is developed for retuning model-based controllers to improve the behavior of a packed-bed tubular CO oxidation reactor under autothermal operation. MOBECS is a supervisory expert system designed to tailor the process control system for a tubular autothermal reactor in response to process or control system faults, and changes in the process behavior. Specific functions include process fault diagnosis, control system performance monitoring and trouble-shooting, controller tuning and control system restructuring. As this work progresses, we will also address the problems of sensor placement, state estimation and process identification. Because of the high degree of coupling and interaction between process and control system entities, objects are the best knowledge representation for a process control expert system. The class—object structures of MOBECS is divided into three orthogonal trees representing the process and control system hierarchies and the topology of the system. Using this structure, knowledge is divided into general knowledge applicable to any process or control system and knowledge that is domain specific. The general knowledge is stored in the class structures and, together with generalized rules, forms a knowledge base kernel. This permits rapid prototyping of other applications of MOBECS. Properties are defined as high as possible in the class tree structure and inherited downwards. Knowledge specific to the process is stored in the objects at the leaves of the trees. Rules form the reasoning portion of the knowledge base and contain the causal relationships, meta-knowledge and performance monitoring functions. Rules that perform general monitoring and troubleshooting are applied at the class level through pattern matching. Rule sets are linked through context relationships to identify indirect relationships to the inference engine. These relationships are used with the process topology tree to reduce the search space when a fault is detected. The process monitoring and instability detection rules have been tested by simulating the inputs to the expert system. At the present time, experimental validation of the MOBECS prototype is being undertaken. Once the MOBECS prototype has been fully tested, the knowledge base will be extended to incorporate more complex fault diagnosis, state estimation, sensor placement and controller restructuring.
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- Title
- Recording and Reproducing Head for Wire Recorders
- Creator
- Camras, Marvin
- Date
- 1948-02-10
- Description
-
Sponsorship: Armour Research Foundation
United States Patent
- Title
- Solid State Shear Extrusion Pulverization
- Creator
- Shutov, Fyodor, Ivanov, George, Arastoopour, Hamid
- Date
- 2009-05-11, 1995-05-16
- Description
-
A process and apparatus for pulverization of natural and synthetic polymeric material by heating to a pre-melt or softening temperature below...
Show moreA process and apparatus for pulverization of natural and synthetic polymeric material by heating to a pre-melt or softening temperature below its melting point, cooling and applying high normal and shear stresses sufficient to form fine powder, and fluidizing the powder in a gas stream preventing its agglomeration. The same process and apparatus is suitable for enhancement of reactivity of polymeric and solid monomeric material to form homopolymers, copolymers, and new polymeric materials.
Sponsorship: Illinois Institute of Technology
United States Patent
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- Title
- Gyroscope
- Creator
- Altman, Samuel P.
- Date
- 1959-03-03
- Description
-
Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent
- Title
- Nonlinear Contingency Screening for Voltage Collapse
- Creator
- Flueck, Alexander Joel, Dondeti, Jayabharath Reddy
- Date
- 2009-05-14, 2002-12-17
- Description
-
A method for estimating the severity of generator unit outage and multi-terminal branch outage contingencies with respect to voltage collapse...
Show moreA method for estimating the severity of generator unit outage and multi-terminal branch outage contingencies with respect to voltage collapse in large-scale electric power systems which includes the steps of estimating a post-contingency saddle-node bifurcation induced voltage collapse point of an electric power system following a set of generator unit outages and/or a set of branch outages and calculating a distance to collapse of said power system. The post-contingency voltage collapse point is determined by application of a nonlinear contingency screening method.
Sponsorship: Illinois Institute of Technology
United States Patent
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- Title
- Magnetic Recording System Using Transducer with Flux Path
- Creator
- Camras, Marvin
- Date
- 2009-04-29, 1972-08-01
- Description
-
A video transducer system comprising a magnetic head having a magnetic core with a loop magnetic signal flux path including a scanning gap,...
Show moreA video transducer system comprising a magnetic head having a magnetic core with a loop magnetic signal flux path including a scanning gap, and a magnetic record medium coupled to the core at the scanning gap.
Sponsorship: IIT Research Institute
United States Patent
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- Title
- Motion Picture Film
- Creator
- Camras, Marvin
- Date
- 1957-02-19
- Description
-
Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent
- Title
- Differential Spool Drive
- Creator
- Fischer, John J., Hadley, Donald W.
- Date
- 1951-02-20
- Description
-
Sponsorship: Armour Research Foundation of Illinois Institute of Technology
United States Patent
- Title
- Agricultural Rehabilitation Tower
- Creator
- Garcia, Rodrigo, Lee, Jennifer
- Date
- 5/4/2011, 2011-05
- Description
-
to create a vertical community bound together by two key issues/requirements in Korean society: urban agriculture and mental health care to...
Show moreto create a vertical community bound together by two key issues/requirements in Korean society: urban agriculture and mental health care to create a ‘vertical façade farm’ capable of producing 156 tons of vegetables (predominantly lettuce, tomatoes, peppers, and strawberries) and 200 tons of fish per year to create a mental health sanctuary (or sanatorium) that provides short term (days), midterm (months) and long term (years) residence and care for people with mental health issues that may require physical operations and/or psychological care. to actively engage the mental health residents in aspects of the agricultural production to draw on research showing that engagement with plants/nature assists in mental healing. to create a large multi-purpose space at the ground floor of the building which will largely serve as a farmer’s market for sale of the agricultural produce and engagement between the community residents and the public to create a series of gardens/green spaces at height within the complex, as well as vertical green walls, for healing (residents and urban issues) to use the double-skin ‘façade farm’ for assisting in passive natural ventilation of internal spaces
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- Title
- Magnetic Analog to Digital Converter
- Creator
- Cameron, Scott H.
- Date
- 4/23/2009, 1966-03-01
- Description
-
Sponsorship: IIT Research Institute
United States Patent
- Title
- WIDESPAN: 2030-board 2
- Creator
- Ninan, Janice
- Date
- 2011-05, 2010-12
- Description
-
Widespan design.Investigating the integration of windmills into longspan structure and investigating the axial forces of tension to span...
Show moreWidespan design.Investigating the integration of windmills into longspan structure and investigating the axial forces of tension to span grater spans using virtual depth concepts with slender lightweight design.
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- Title
- Greenweb
- Creator
- Thomas, Boerman
- Date
- 2010-07-29
- Title
- CONSTITUTIVE BEHAVIOR AND MODELING OF AL-CU ALLOY SYSTEMS
- Creator
- Turkkan, Omer Anil
- Date
- 2013-05-07, 2013-05
- Description
-
High speed deformation events such as caused by projectile penetration, fragment impact and shock/blast loading are of great importance in...
Show moreHigh speed deformation events such as caused by projectile penetration, fragment impact and shock/blast loading are of great importance in designing materials and structures for army applications. In these events, materials are subjected to large strains, high strain rates and rapid increase in temperature due to thermoplastic heating. In such severe conditions, overall performance is determined by the evolution of flow stress, failure initiation and propagation, and commonly in the form of adiabatic shear banding. Some of 2XXX series aluminum-copper (Al-Cu) alloys are recognized for their decent ballistic properties, and therefore they have been used as an armor material for lightweight U.S. Army vehicles. Most recently, an Al-Cu-Mg-Mn-Ag alloy labeled as Al 2139-T8 has been developed and is evaluated by the U.S. Army Research Labs. because of its better ballistic properties and higher strength than its predecessors. The underlying microstructure is believed to be the key element for this superior performance. The goal of this study is to explore the effect of composition and microstructural features on overall dynamic material behavior by examining mechanical and deformation behavior of different Al-Cu material systems. Starting from the pure single crystal and polycrystalline Al structures, and adding a different element to chemical composition in each step (i.e., Cu, Mg, Mn, Ag), mechanical response of these different systems has been investigated. For all alloy systems with the exception of single crystal Al, mechanical tests have been performed at room and elevated temperatures covering quasi-static ( to ) and dynamic ( to strain rate regimes. xiv Shear-compression specimens promoting localized shear deformation have been used to explore tendency of each one of these materials to failure by adiabatic shear banding. In addition to phenomenological Johnson-Cook Model (JCM), physics based Zerrilli-Armstrong and Mechanical Threshold Models have been studied to model the constitutive response of Al-Cu alloys over a wide range of strain rates and temperatures.. An improved ZA model has been developed to better capture the trends in experimental data.
M.S. in MECHANICAL, MATERIALS, AND AEROSPACE ENGINEERING, May 2013
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- Title
- VIBRATIONAL CONTROL OF AN EXOTHERMIC REACTION IN A CSTR - THEORY AND EXPERIMENTS
- Creator
- Cinar, A., Deng, J., Meerkov, S. M., Shu, X. S.
- Date
- 1987-03
- Publisher
- AMER INST CHEMICAL ENGINEERS
- Description
-
Vibrational control is a method for modification of dynamic properties of linear and nonlinear systems by introducing fast, zero-average...
Show moreVibrational control is a method for modification of dynamic properties of linear and nonlinear systems by introducing fast, zero-average oscillations in the system's parameters. In this paper, forced oscillations introduced in the input flow rates of an exothermic continuous stirred-tank reactor (CSTR) are shown to result in a modification of the S-shaped steady state curve. This modification leads to a possibility of operating a CSTR at an asymptotically stable period regime located in the vicinity of an unstable steady state of the reactor system with stationary input flow rates. Thus, vibrations of the input flow rates can be viewed as a stabilizing mechanism for exothermic CSTR's.
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- Title
- QUALITY-OF-SERVICE AWARE SCHEDULING AND DEFECT TOLERANCE IN REAL-TIME EMBEDDED SYSTEMS
- Creator
- Li, Zheng
- Date
- 2015, 2015-05
- Description
-
For real-time embedded systems, such as control systems used in medical, automotive and avionics industry, tasks deployed on such systems...
Show moreFor real-time embedded systems, such as control systems used in medical, automotive and avionics industry, tasks deployed on such systems often have stringent real-time, reliability and energy consumption constraints. How to schedule real-time tasks under various QoS constraints is a challenging issue that has drawn attention from the research community for decades. In this thesis, we study task execution strategies that not only minimize system energy consumption but also guarantee task deadlines and reliability satisfaction. We first consider the scenario when all tasks are of the same criticality. For this case, two task execution strategies, i.e. checkpointing based and task re-execution based strategies are developed. Second, considering the scenario when tasks are of different criticalities, a heuristic search based energy minimization strategy is also proposed. When tasks are of different criticalities, a commonly used approach to guaranteeing high-criticality task deadlines is to remove low-criticality tasks whenever the system is overloaded. With such an approach, the QoS provided to low-criticality tasks is rather poor, it can cause low-criticality tasks to have high deadline miss rate and less accumulated execution time. To overcome this shortcoming, we develop a time reservation based scheduling algorithm and a two-step optimization algorithm to meet high-criticality task deadlines, while minimizing low-criticality task deadline miss rate and maximizing their accumulated execution time, respectively. As many-core techniques mature, many real-time embedded systems are built upon many-core platforms. However, many-core platforms have high wear-out failure rate. Hence, the last issue to be addressed in the thesis is how to replace defective cores on many-core platforms so that deployed applications’ real-time properties can be maintained. We develop an offline and an online application-aware system reconfiguration strategy to minimize the impact of the physical layer changes on deployed real-time applications. All the developed approaches are evaluated through extensive simulations. The results indicate that the developed approaches are more effective in addressing the identified problems compared to the existing ones in the literature.
Ph.D. in Computer Science, May 2015
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