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Title: DETECTING GNSS SPOOFING ATTACKS USING INS COUPLING
Creator: Tanil, Cagatay
Date: 2016, 2016-12
Description: Vulnerability of Global Navigation Satellite Systems (GNSS) users to signal spoofing is a critical threat to positioning integrity, especially...
Show moreVulnerability of Global Navigation Satellite Systems (GNSS) users to signal spoofing is a critical threat to positioning integrity, especially in aviation applications, where the consequences are potentially catastrophic. In response, this research describes and evaluates a new approach to directly detect spoofing using integrated Inertial Navigation Systems (INS) and fault detection concepts based on integrity monitoring. The monitors developed here can be implemented into positioning systems using INS/GNSS integration via 1) tightly-coupled, 2) loosely-coupled, and 3) uncoupled schemes. New evaluation methods enable the statistical computation of integrity risk resulting from a worst-case spoofing attack – without needing to simulate an unmanageably large number of individual aircraft approaches. Integrity risk is an absolute measure of safety and a well-established metric in aircraft navigation. A novel closed-form solution to the worst-case time sequence of GNSS signals is derived to maximize the integrity risk for each monitor and used in the covariance analyses. This methodology tests the performance of the monitors against the most sophisticated spoofers, capable of tracking the aircraft position – for example, by means of remote tracking or onboard sensing. Another contribution is a comprehensive closed-loop model that encapsulates the vehicle and compensator (estimator and controller) dynamics. A sensitivity analysis uses this model to quantify the leveraging impact of the vehicle’s dynamic responses (e.g., to wind gusts, or to autopilot’s acceleration commands) on the monitor’s detection capability. The performance of the monitors is evaluated for two safety-critical terminal area navigation applications: 1) autonomous shipboard landing and 2) Boeing 747 (B747) landing assisted with Ground Based Augmentation Systems (GBAS). It is demonstrated that for both systems, the monitors are capable of meeting the most stringent precision approach and landing integrity requirements of the International Civil Aviation Organization (ICAO). The statistical evaluation methods developed here can be used as a baseline procedure in the Federal Aviation Administration’s (FAA) certification of spoof-free navigation systems. The final contribution is an investigation of INS sensor quality on detection performance. This determines the minimum sensor requirements to perform standalone GNSS positioning in general en route applications with guaranteed spoofing detection integrity.
Ph.D. in Mechanical and Aerospace Engineering, December 2016
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Title: FLOW DISTRIBUTION AND TURBULENCE CHARACTERISTICS IN AN URBAN ENVIRONMENT
Creator: Goudarzi, Sepehr Aboutorabi
Date: 2014, 2014-12
Description: The amount of the urban flow studies has been excessively increased during past decade. Pollutant dispersion quality has been the main...
Show moreThe amount of the urban flow studies has been excessively increased during past decade. Pollutant dispersion quality has been the main motivation in these investigations. Besides, a more recent goal is to provide a spatial map of the flow distribution which can be used for micro aerial vehicles (MAV) flight control. These all have developed advanced methodologies in both computational and experimental researches. In this study flow distribution and characteristics are investigated in a 7×5 urban array model (blocks are representing buildings) in a low-speed wind tunnel. Stereoscopic Particle Image Velocimetry (SPIV) is employed as the velocimetry method to acquire three-dimensional velocity filed in the three-dimensional region of street areas. A large amount of SPIV data was acquired in four consecutive streets for four wind incidence angle. The evolution of the three-dimensional coherent structures is investigated. Also, flow characteristics are studied using parameters such as mean velocity, turbulent kinetic energy (TKE), vorticity magnitude and Reynolds stress tensor components. All flow characteristics are studied in four consecutive streets of the array. Also, the effects of the wind direction on the flow characteristics and arch vortex location are studied. A valuable achievement of this study is to suggest a method to find the location of the arch vortex legs, and find the angle between the arch horizontal axis with the spanwise direction (𝜑). It is shown that this angle is increasing significantly in variation of angle of incidence (AOI) in the range of 𝐴𝑂𝐼=0° to 𝐴𝑂𝐼=15°. The rate of increment of 𝜑 is much slower between 𝐴𝑂𝐼=15° and 𝐴𝑂𝐼=30° but the 𝜑 range is still greater than AOI. Existence of geometrical symmetry in 𝐴𝑂𝐼=0° case, brings unique features for this condition such as zero spanwise flow velocity in streets.. Increasing AOI to higher magnitudes will cause severe change in flow distribution and turbulence level, in the sense that turbulence intensity starts to impoverish.
M.S. in Mechanical and Aerospace Engineering, December 2014
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Title: A study of water distribution from automatic sprinklers
Creator: Schmidt, J. L., Alling, C. R
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofwaterdist00schm
Thesis (B.S.)--Armour Institute of Technology, 1907 B. S. in Fire Protection Engineering,...
Show morehttp://www.archive.org/details/studyofwaterdist00schm
Thesis (B.S.)--Armour Institute of Technology, 1907 B. S. in Fire Protection Engineering, 1907
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Title: A system of automatic train control
Creator: Morgan, Charles Woodward
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/systemofautomati00morg
Thesis (B.S.)--Armour Institute of Technology, 1911 Includes bibliographical references...
Show morehttp://www.archive.org/details/systemofautomati00morg
Thesis (B.S.)--Armour Institute of Technology, 1911 Includes bibliographical references and index B.S. in Mechanical Engineering, 1911
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Title: THERMAL AND FLUID FLOW FEASIBILITY STUDY OF A CIRCULAR COUETTE FLOW REACTOR VIA PLANAR LASER-INDUCED FLUORESCENCE IMAGING
Creator: Bittner, Peter R.
Date: 2012-04-28, 2012-05
Description: Liquid fueled microcombustors face many challenges in their development, the most prominent being high temperature gradients and radiative...
Show moreLiquid fueled microcombustors face many challenges in their development, the most prominent being high temperature gradients and radiative effects. Because the walls of microcombustors are thin, they offer very little resistance to conductive heat transfer, regardless of the materials used. This can cause very high heat losses that lead to large temperature gradients in the gas compared to nearly uniform temperatures inside conventional combustion chambers. In this investigation a circular Couette flow reactor (CCFR) and planar laser induced fluorescence (PLIF) are used to examine the feasibility of studying vapor distributions of a monodisperse acetone droplet stream, formed by a vibrating orifice aerosol generator (VOAG), exposed to combinations of varying velocity gradients, temperature gradients and radiant heating. The acetone droplets are injected through various ports on the CCFR to vary the time for vaporization of the droplets inside the reactor. Initial results of the operating CCFR uses acetone droplets seeded into the test section to demonstrate the fluorescence of the liquid and vapor acetone within the test section.
M.S. in Mechanical, Materials, and Aerospace Engineering, May 2012
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Title: SIMULATIONS OF CENTERLINE DEFECT CLOSURE IN OPEN DIE FORGING
Creator: Gangatirkar, Suhasini
Date: 2014, 2014-12
Description: Open die forging is a technique widely used to achieve desired shape and sound mechanical properties. Due to large sizes, the ingots often...
Show moreOpen die forging is a technique widely used to achieve desired shape and sound mechanical properties. Due to large sizes, the ingots often have internal defects such as porosity, shrinkage cavities which damage the overall quality of the final product and affect the mechanical properties of the material. The voids developed during cooling of the ingot have to be treated in the initial forming operation known as cogging which depends on parameters such as die width ratio, die overlap, feed ratio, die shape etc. In this work, finite element method has been used to identify different aspects affecting centerline defect closure, material properties, effect of friction coefficient, relationship between effective strain and the grain size. FORGE 2011 and FORGE NxT 1.0 by Transvalor Corp were used to create numerical models. The material used in this case is H13. Material data and compression test samples were obtained from experiments in a Gleeble 3500. Physical experiments carried out on the Gleeble 3500 were used to determine the coefficient of friction for samples treated at different temperature, strain and strain rates. The effect of these parameters on coefficient of friction was studied in later part of the study. The formulae from the literature used to calculate the coefficient of friction was validated by using simulation models of the compression test samples. These samples were also used to study fraction recrystallized for a particular sample to study the relationship between effective strain and microstructure. Comparisons between validation experiments and simulations showed that there was good agreement between the two and established the effective strain criterion for void closure. From the conclusions obtained from validation experiments, optimal pass schedule was developed to ensure closure of internal voids and uniform distribution of effective strain along centerline for sound quality of the workpiece by changing die overlap percentage every two passes.
M.S. in Material Science Engineering, December 2014
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Title: A study of anti-friction lineshaft bearings
Creator: Katzinger, Arthur, Alte, Arthur S.
Date: 2009, 1916
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofantifrict00katz
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 212-220

Title: HOT DUCTILITY BEHAVIOR IN THE CONTINUOUS CASTING OF NIOBIUM-BEARING MICROALLOYED STEELS
Creator: Jansto, Steven George
Date: 2013, 2013-12
Description: Over 200 million tons of Niobium-bearing steels were continuously cast and hot rolled globally in 2012. These Nb-bearing plate, bar and sheet...
Show moreOver 200 million tons of Niobium-bearing steels were continuously cast and hot rolled globally in 2012. These Nb-bearing plate, bar and sheet products are manufactured throughout the world. The melting and casting practices to assure production of crack-free slabs, billets and blooms of high surface quality is presented. Much has been published about the traditional ductility trough associated with higher carbon equivalent steels with and without microalloy additions of Nb, V and/or Ti. The focus has primarily been on the chemistry and optimal composition based upon the literature review. However, the steelmaking and process metallurgy parameters are rarely correlated to the hot ductility behavior. Most studies involve laboratory produced heats, but this research is based upon industrial produced samples.The hot ductility troughs associated with simple carbon-manganese steels can also result in surface and internal quality issues if certain steelmaking and casting parameters are not followed. Although high carbon equivalent steels exhibit inherently lower hot ductility behavior, as measured by percent reduction in area at elevated temperature, these steels still exhibit sufficient ductility to satisfactorily meet the unbending stress and strain gradients existing in the straightening section of most casters. The % Reduction in Area significantly overstates the minimum ductility required for crack-free casting of Nb-bearing steels. The relationship between the steelmaking and caster operation and the resultant slab quality is related through the hot ductility behavior. This global Nb-bearing continuous casting steel research study introduces the strain energy as an improved xxi measure of the hot ductiity behavior. The incidence of cracking is primarily related to the steelmaking and caster process parameters and steel chemistry is secondary. These parameters include the elemental residual chemistry level, superheat variation, transfer ladle temperature stratification, oscillation frequency and stroke, mould flux incompatibility, casting speed fluctuation, and excessive secondary cooling.
PH.D in Materials Science and Engineering, December 2013
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Title: The study and design of spray nozzles as applied to the De La Vergne oil engine
Creator: Harman, William E. S, Ward, Fred L
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studydesignofspr00harm
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 2

Title: DISCONTINUOUS IN THE NI-CO-AL PRECIPITATION ALLOY SYSTEM
Creator: Liu, Tian
Date: 2014, 2014-05
Description: The synthesis of nanoplates of 0 by use of discontinuous precipitation was investigated in the Ni-Co-Al alloy system. A series of experiments,...
Show moreThe synthesis of nanoplates of 0 by use of discontinuous precipitation was investigated in the Ni-Co-Al alloy system. A series of experiments, such as heat treatment, cold rolling, and electrolytic etching, have been performed to develop the desired microstructure. Nanostructured materials have great potential in a number of applications, such as catalysis, light weight structural materials, thermal management and pollution reduction. Kinetic information of the Ni-Co-Al alloy was obtained through measuring the optical micrographs of samples aged at di erent temperatures. The morphology of the nanostructure of the Ni-Co-Al alloy was investigated using scanning electron microscopy (SEM). The mechanical property (hardness) of the Ni-Co-Al alloy was obtained in di erent conditions as well. The Ni-Co-Al alloys were recrystallized in di erent ways. The texture of the alloys were determined using electron backscattered di raction (EBSD). After analyzing those experimental results, we nd that the discontinuous precipitation goes to completion in the Ni-Co-Al alloy. The discontinuous precipitates present a lamellar structure. The size of plates is similar with the spacing between plates and achieves a nanoscale architecture. The TTT curve of the Ni-Co-Al alloy with a composition of 43 at.% Ni, 48 at.% Co and 9 at.% Al provides abundant kinetic information. Further work is needed to produce a strong cube texture ((100) planes parallel to the foil surface).
M.S. in Materials Engineering, May 2014
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Title: PARAMETRIC COST ESTIMATION MODEL OF INTEGRATED REACTOR VESSEL UNDER MODULAR CONSTRUCTION WITHIN A FACTORY ENVIRONMENT
Creator: Chen, Xuan
Date: 2013, 2013-12
Description: High initial cost is one of the major barriers for the nuclear power industry. Small modular reactors (SMR) may be a solution to this problem...
Show moreHigh initial cost is one of the major barriers for the nuclear power industry. Small modular reactors (SMR) may be a solution to this problem because they have a much smaller financial barrier. In this thesis, parametric cost estimation modeling studies have been performed for the SMR integrated reactor vessel (IRV) under a factory environment. Based on different prior fabrication experiences, three scenarios have been studied, and the corresponding possible manufacturing costs of the entire IRV and its subcomponents have been estimated. To explore the cost allocation, the total cost has been divided into five cost contributors: labor, material, tooling labor, tooling replacement, and other. The results have been analyzed and discussed.
M.S. in in Mechanical, Material and Aerospace Engineering, December 2013
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Title: Tests on Kerr steam turbine and direct-connected Worthington centrifugal pump
Creator: James, Sydney Vincent, Jackson, Irving Foster
Date: 2009, 1907
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testsonkerrsteam00jame
Thesis (B.S.)--Armour Institute of Technology; Includes index

Title: Study of the transmission of heat through tile and concrete fireproofing
Creator: Snow, C. A.
Date: 2009, 1912
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyoftransmiss00snow
Thesis (B.S.)--Armour Institute of Technology

Title: COMPUTATIONAL ACCESS FLOW REDUCTION EFFECT ON WALL SHEAR STRESS IN BRACHIOCEPHALIC FISTULAE
Creator: Wlodarczyk, Marta P.
Date: 2017, 2017-05
Description: The population of patients with end stage renal disease (ESRD) is growing at a rate higher than the global population. The only viable...
Show moreThe population of patients with end stage renal disease (ESRD) is growing at a rate higher than the global population. The only viable treatment for these patients is a kidney transplant. However, in the absence of a suitable kidney donor, renal patients are left with hemodialysis as a renal replacement therapy. Hemodialysis is facilitated through arteriovenous fistula (AVF), and the particular interest in this investigation is brachiocephalic fistula (BCF). The survival of dialysis patients depends on maintaining patency of fistula over a prolonged period of time. The extreme hemodynamic environment that is created by BCF triggers the onset of neointimal hyperplasia (NH) in most renal dialysis patients, which leads to access failure via stenosis. This is because the hemodynamics in AVF are well outside the normal physiological range. Computational fluid dynamics (CFD) along with shape optimization allows for the study of the hemodynamic parameters such as wall shear stress that have been shown to be detrimental in the future occurrence of cephalic arch stenosis. In this study, CFD modeling and identification of hemodynamic patterns was possible in three dimensions due to advanced post processing of IVUS patient-specific geometries. A method utilizing 3D CFD and shape optimization has been developed to implement Miller’s banding method used in clinical practice to evaluate its impact on WSS and onset of neointimal hyperplasia. The level of banding represented by a constriction is in fact a patient specific value and is not a trivial solution of minimum flow rate necessary to conduct hemodialysis; hence suggesting that even restoring the inlet velocity to the velocity pre-fistula creation might not reduce incidence of cephalic arch stenosis. The findings of this study support the previous hypothesis that non-homeostatic WSS distributions trigger neointimal hyperplasia and resulting venous stenosis. The important outcome is that the presented computational framework allows for evaluation of Miller's banding method for reducing the blood flow rate via surgical constriction and identification of a patient-specific banding level that restores the WSS to the normal physiological range.
M.S. in Mechanical and Aerospace Engineering, May 2017
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Title: Test of a three ton refrigerating plant
Creator: Beerbaum, A. J, Strale, N. W, Keachie, P. L.
Date: 2009, 1912
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testofthreetonre00beer
Thesis (B.S.)--Armour Institute of Technology, 1912 B.S. in Mechanical Engineering, 1912

Title: FLOW FIELD STRUCTURE AND UNSTEADY AERODYNAMIC LOADS ON AN AIRFOIL IN SURGING FLOW
Creator: Iliev, Simeon Milenov
Date: 2015, 2015-05
Description: Airfoils subject to unsteady freestream velocity as in the case of helicopter rotor blades and vertical axis wind turbines have been observed...
Show moreAirfoils subject to unsteady freestream velocity as in the case of helicopter rotor blades and vertical axis wind turbines have been observed to exhibit very interesting lift behavior. Depending on the frequency of the oscillating freestream velocity, the uctuating lift amplitude can reach values as much as twice of that predicted by a quasi-steady approximation or as low as only one-half of that. Experimental data and analysis presented in this study provide the exact relationship between surging ow frequency and amplitude of the uctuating lift force for a range of reduced fre- quencies between k=0.1 and k=1.5. Furthermore, surface pressure measurements on the suction surface of the airfoil are used to supplement the measured lift force data and provide a measure of the level of unsteady ow e ects. Finally, experimental particle image velocimetry ow eld data is presented for the two surging ow cases corresponding to the maximum and minimum uctuating lift amplitude and is used to extract coherent ow eld structures which are related to the respective lift be- havior. Both the experimental lift force data and ow eld structures are compared to corresponding, low Reynolds number numerical simulation results.
M.S. in Mechanical and Aerospace Engineering, May 2015
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Title: Study and design of tall office building power plant
Creator: Hill, Warren E
Date: 2009, 1905
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studydesignoftal00hill
Thesis (B.S.)--Armour Institute of Technology

Title: Test of a Delavergne oil engine
Creator: Sieck, William
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/testofdelavergne00siec
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Mechanical Engineering, 1911

Title: A NOVEL METHOD FOR THE IMPLEMENTATION OF STRUCTURAL CONTACT IN FINITE ELEMENT METHODS OFFERING SIMPLIFIED TREATMENT OF ENERGY DISSIPATION
Creator: Grudzinski, James John
Date: 2012-04-24, 2012-05
Description: A novel method for implementing contact/impact in an implicit nite element formulation is presented. The method uses the ideas of buoyancy to...
Show moreA novel method for implementing contact/impact in an implicit nite element formulation is presented. The method uses the ideas of buoyancy to enforce the normal contact constraint and a velocity dependent force to model energy dissipation. Upon contact (penetration) a normal force equal to the depth of penetration times a target weight density (di erent and much larger than the actual material weight density) creates a normal pressure on the contacting body. In addition to the buoyancy force, the penetrating surface area is subjected to a drag-like force that acts in a direction opposite the velocity vector of the penetrating node of the contacting body . This rate dependence is broken up into components tangential and normal to the target surface. The normal component of the drag performs two functions. First it provides for an energy absorbing mechanism similar to a coe cient of restitution for modeling non-conservative systems. Secondly, it can provide damping (analogous to mathematical damping) which can aid in solution convergence. The tangential component of the damping force serves the function of modeling friction in a simpli ed manner. The method applies contact forces in the manner of external forces and as such lends itself well to simpli ed contact detection schemes which rely on functional representation of bodies. The method is described and demonstrated through several examples including a comparison to experimental data.
Ph.D. in Mechanical and Aerospace Engineering, May 2012
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Title: The utility of the pyrometer on carburetted water gas machines
Creator: Heath, Chester S.
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/utilityofpyromet00heat
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Mechanical Engineering, 1911

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