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The Synthesis And Characterization Of Imidazolium Lithium Phthalocyanines, John J. Kelley

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A series of 1,3-di-substituted-imidazolium lithium phthalocyanines, in which the substituents on the imidazolium nitrogens were combinations of methyl, ethyl, pentyl, hexyl, isopropyl, adamantyl or 2,4,6-trimethylphenyl groups, was synthesized. The cation exchange of a single lithium ion of dilithium phthalocyanine for a 1,3-disubstituted-imidazolium ion was performed by mixing their salts in common organic solvents under ambient conditions. This afforded a number of imidazolium lithium phthalocyanines in moderate yields. They exhibited poor solubility in most solvents. Their composition and purity were initially verified by 1H and 13C-NMR and elemental analysis. The 1H-NMR spectra also indicated that the imidazolium and lithium phthalocyanine ions …

Characterization Of Inert Gas Rf Plasma-Treated Indium Tin Oxide Thin Films Deposited Via Pulsed Dc Magnetron Sputtering, Amber Nicole Reed

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In this work, the effects of a post-deposition RF plasma treatment on indium tin oxide (ITO) thin films prepared with pulsed DC magnetron sputtering in argon were investigated. The parameters of the post-deposition were studied to determine what RF power and gas pressure resulted in the greatest reduction in resistivity in the films while producing the smallest increase in substrate temperature for treatments with both argon and oxygen plasmas. The as-deposited (untreated) films and the treated films were characterized using Raman spectroscopy and X-ray diffraction to determine the effects of the post-deposition treatment on the degree of film crystallization. XPS …

Real-Time Hilbert Transform And Autocorrelation For Digital Wideband Communication Applications, Murthy, Dilip Srinivasa

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Digital wideband receiver plays a key role in communication and radar systems, and it is used detect and analyze wide range of radio frequency (RF) signals. A digital Instantaneous Frequency Measurement (IFM) receiver is designed, where implementation of a real-time architecture of a Hilbert transform and autocorrelation algorithm is presented. Real-time architecture performs continuous monitoring and processing of the incoming signal. Prior to the previous one bit design, the input data fed to the Hilbert transform is 8-bit wide at a clock rate of 320 MHz with the input data rate is increased by a factor of eight, an 8-bit …

Modeling Training Effects On Task Performance Using A Human Performance Taxonomy, Douglas P. Meador

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There is little argument that modern military systems are very complex, both in terms of the resources in time and money to develop them and the infrastructure that is required to produce trained operators. To properly execute human systems integration during the acquisition process, systems built to train operators must be developed that optimize training. Consequently, the training system community would benefit from simulation models that provide the ability to make accurate predictions of training processes, and allow the decision maker to specify an optimum combination of operator performance after training and the cost of that training. The goal of …

Integrated Inductors, Mandar Dilip Kavimandan

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Integrated inductors, also called spiral inductors, on-chip inductors, or planarinductors, are inseparable part in radio frequency integrated circuits (RFICs). Increasing growth in RFICs from the past few decades has forced study of these components in greater detail. Apart from IC inductors, there are several components mounted on a chip - namely capacitors, resistors, MOSFETs, diodes etc. It is extremely important to understand the electrical and magnetic behavior of all these components. Electrical behavior of these components is easy to understand. However, the real challenge lies in realizing and predicting the magnetic behavior of components, namely, inductors and capacitors. Capacitors have …

Non-Linear Shunting Of Piezo-Actuators For Vibration Suppression, Anisetti Anusha

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Vibrations at a resonant frequency lead to catastrophic failure or at the very least, shorten the life span of the structure due to fatigue. These problems force engineers to implement damping techniques. Smart materials have been used over two decades to reduced vibration amplitudes. Recently, there has been much research and development on smart materials and structures.

This work introduces an innovative approach for vibration suppression using passively shunted piezolectric materials. Initially linear circuit elements such as resistors, capacitors, and inductances, or building a non-linear circuit with different impedance designs were used. Instead of such elements, a switched electromechanical shunt …

A Tabu Search Heuristic For Multi-Period Clustering To Rationalize Delivery Operations, Surya Sudha Khambhampati

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Delivery operations use centralized warehouses to serve geographically distributed customers. Resources (e.g. personnel, trucks, stock, and equipment) are scheduled from the warehouses to distributed locations with the aim of: (a) meeting customer demands and, (b) rationalizing delivery operation costs. My thesis investigates the problem of clustering customers based on their geographical vicinity and their multi-period demands, while optimally scheduling resources. The problem addresses with-and-without capacity constraints of vehicles at the warehouse. This problem is proven to be NP-Hard. Hence, solutions using state-of-the-art exact methods such as branch and bound are not pertinent due to the computation complexity involved. We develop …

Dynamic Pneumatic Muscle Actuator Control System For An Augmented Orthosis, Maria J. Gerschutz

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This dissertation develops, implements and analyzes a dynamic control system for a pneumatic muscle actuator (PMA) utilizing an augmented orthosis application. The application of PMAs are limited due to poor control capabilities resulting from dynamic nonlinearities. An adequate control system applying an appropriate dynamic pneumatic muscle actuator model increases the potential utility of PMAs in high-force applications including augmented orthotic applications.

The research conducts an initial analysis evaluating the feasibility of PMAs in high-force applications (force assistance with minimal displacement). A computational simulated control system (CSCS) is developed to analyze three different control schemes. The three PMA control schemes (position …

Locked Rooms And Interpreting Readers: The Role Of Embedded Texts In The Locked-Room Mysteries Of Poe, Leroux, And Christie, Carolyn E. Stoermer

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As closed narratives, locked-room mysteries risk the sense of interpretive play for which the larger detective genre is known. To mitigate this risk, writers like Edgar Allan Poe, Gaston Leroux, and Agatha Christie incorporate embedded texts into their locked-room stories. These recreated documents encourage readers' involvement by eliciting culturally specific interpretive reactions. Studying how these authors' embedded texts simultaneously innovate and conserve within the locked-room subgenre brings critics closer to understanding exactly how the detective story earned its reputation as one of the most engaging forms of fiction.

The Impact Of Nutrient Availability And Algal Community On Carbon Isotope Fractionaion In Crystal Lake, Clark County, Ohio, April R. Wisebaker

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Crystal Lakes are a group of four interconnected lakes, located in southwestern Clark County, Ohio. Several studies have looked at separate geochemical and isotopic information at this location. However, no one has thoroughly studied the relationship between the algal community, geochemistry, and carbon isotope fractionation within Crystal Lake. The fractionation of carbon isotopes of dissolved inorganic carbonate is greatly affected by the process of photosynthesis; the amount of photosynthesis is affected by the amount of algae in the aquatic community; the amount of algae is affected by the available nutrients in system. Therefore, there should be a correlation between the …

Algorithmic Techniques Employed In The Isolation Of Codon Usage Biases In Prokaryotic Genomes, Douglas W. Raiford Iii

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While genomic sequencing projects are an abundant source of information for biological studies ranging from the molecular to the ecological in scale, much of the information present may yet be hidden from casual analysis. One such information domain, trends in codon usage, can provide a wealth of information about an organism's genes and their expression. Degeneracy in the genetic code allows more than one triplet codon to code for the same amino acid, and usage of these codons is often biased such that one or more of these synonymous codons is preferred. Isolation of translational efficiency bias can have important …

Energy Efficient Image Video Sensor Networks, Paul Anthony Bender

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Image Video Sensor Networks are emerging applications for sensor network technologies. The relatively large size of the data collected by image video sensors presents new challenges for the sensor network in terms of energy consumption and channel capacity. We address each of these issues through the use of a high density network deployment utilizing some nodes as dedicated relay nodes.

A high density network allows network nodes to reduce their transmission power. This reduction in transmission power allows each node to conserve power and simultaneously increases the potential for spatially concurrent transmissions within the network, resulting in improved network throughputs. …

A Study Of Multi-Echelon Inventory Systems With Stochastic Capacity And Intermediate Product Demand, Suman Niranjan

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The research in this dissertation involves the study of several multi-echelon inventory systems with stochastic capacity and intermediate product demand. Specifically we analyze the behavior of the system which consists of several intermediate product demands. The analysis is primarily three fold i) developed update (relational) equations for all the multi-echelon inventory systems under several inventory allocation policies, ii) develop two simulation optimization approaches 1) OptQuest framework, and 2) IPA (Infinitesimal Perturbation Analysis) framework, used to minimize the total cost of the inventory systems that satisfy the desired customer service level, iii) obtain numerical results for all the multi-echelon inventory systems …

Shore Wives: The Lives Of British Naval Officers' Wives And Widows, 1750-1815, Amy Lynn Smallwood

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This thesis provides an analysis of the lives of mid- to late-eighteenth century Royal Navy officers'wives and widows, including how they coped with the challenges of being separated from their husbands for extended periods of time. This separation forced them to accept additional financial and management responsibilities. By successfully managing these tasks, they proved that women were capable of managing money, purchasing property, rearing and educating children, working the patronage system, being political activists, dealing with bureaucracy, and networking. Shore wives performed these duties with the very real fear that their husbands might never come home alive. By taking up …

Evaluation Of Overlay/Underlay Waveform Via Sd-Smse Framework For Enhancing Spectrum Efficiency, Vasu D. Chakravarthy

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Recent studies have suggested that spectrum congestion is mainly due to the inefficient use of spectrum rather than its unavailability. Dynamic Spectrum Access (DSA) and Cognitive Radio (CR) are two terminologies which are used in the context of improved spectrum efficiency and usage. The DSA concept has been around for quite some time while the advent of CR has created a paradigm shift in wireless communications and instigated a change in FCC policy towards spectrum regulations. DSA can be broadly categorized as using a 1) Dynamic Exclusive Use Model, 2) Spectrum Commons or Open sharing model or 3) Hierarchical Access …

Object Similarity Through Correlated Third-Party Objects, Ting Sa

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Given a pair of objects, it is of interest to know how they are related to each other and the strength of their similarity. Many previous studies focused on two types of similarity measures: The first type is based on closeness of attribute values of two given objects, and the second type is based on how often the two objects co-occur in transactions/tuples.

In this thesis we study a new behavior-based similarity measure, which evaluates similarity between two objects by considering how similar their correlated third-party object sets are. Behavior-based similarity can help us find pairs of objects that have …

The Effect Of Dissolved Air On The Cooling Performance Of A Partially-Confined Fc-72 Spray, Rebekah Lee Puterbaugh

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The objective of this thesis is to investigate the heat transfer performance of a partially-confined FC-72 spray with varying dissolved air concentrations. An experimental test rig consisting of a spray chamber coupled to a fluid delivery loop system was used to obtain temperature, pressure, and critical heat flux (CHF) data. A downward facing nozzle within the spray chamber allowed the FC-72 fluid to be sprayed onto an upward facing, thick-film, resistor heater. The heater was mounted onto a glass post, with a sump system to allow removal of excess fluid. Type-E thermocouples were imbedded in the post to obtain temperature …

Exploration Of Synthetic Routes To The Sulfoxide And Sulfone Derivatives Of Benzotrithiophenes, Tiffany M. Hall

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The synthesis of new organic materials that have the potential to be utilized in a thermoelectric application are in demand because they are able to convert thermal energy directly into electrical energy. The "end-on" sulfoxide and sulfone derivatives of Benzo[1,2-c:3,4-c':5,6-c'']trithiophene 1 were synthesized for this reason. The "end-on" mode sulfoxide derivative 13 of Benzo[1,2-c:3,4-c':5,6-c'']trithiophene 1 was prepared by utilizing 3-Carboxypyridinium Chlorochromate (CPCC) 16 and AlCl₃, as an oxidizing system. The ¹H NMR (DMSO-d₆) spectrum displayed a singlet peak at 5.03 ppm, and the IR spectrum displayed an absorption at 1059.33cm^-1, which confirmed its …

Paleoenvironment And Lateral Extent Of An Exposed Carbonate Build-Up: Horry County, South Carolina, Lisa A. Raterink

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A carbonate build-up exposed in the Intracoastal Waterway in Horry County, South Carolina is estimated to be Pleistocene to Pliocene in age. The carbonate build-up discontinuously spans approximately 12 kilometers of the waterway. Prominent formations in the area consist of the Waccamaw and the Canepatch Formation. A distinct sand layer is present laterally between the build-up and the excavated waterway bank, which consists primarily of well preserved fossil molluscs and echinoderms.

Field observations show that the carbonate build-up is bluish-gray in color and composed of shell fragments, predominantly mollusc, in a mud matrix. Thin sections analyzed, using a petrographic microscope, …

Analysis And Transformation Of Post-Conditions, Abhinav Vasikarla

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Software engineers have been trying for years to develop a software synthesis system that can transform a formal specification model to a design model from which executable code can be generated. AFIT wide spectrum object modeling environment (AWESOME) is one result of their research. AWESOME presents a formal model as an abstract syntax tree. This model consists mainly of object class specifications. The methods in these classes are specified using pre and post-conditions. The intent of this thesis is to support the transformation of post-conditions to code statements. A post-condition is first categorized as dependent or independent relative to other …

Fpga Design Of A Hardware Efficient Pipelined Fft Processor, Ryan T. Bone

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Digital receivers involve fast Fourier transform (FFT) computations that require a large amount of arithmetic operations. The implementation of a FFT processor is one of the most challenging parts in the realization of a wideband receiver and its hardware complexity is very high. Hence, kernel function FFT processors have been proposed to meet real-time processing requirements and to reduce hardware complexity by rounding the kernel function to predetermined kernel points so as to eliminate the multipliers and use only shifters and adders or subtractors. Because of the nonlinear nature of this approximation by the rounding errors, spurious responses are generated …

Exploration Of Gradient-Type Poly(Arylene Ether)S Via An Abb' Monomer System, Alex V. Dolgov

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Evidence shows that a gradient like copolymer can be synthesized using nucleophilic aromatic substitution, NAS, chemistry. Using the 4-chloro-3-fluoro-4'hydroxydiphenylsulfone monomer, 5, it is possible to control the ratios of the leaving groups, in this case the fluorine and the chlorine, with the right solvent and temperature. Alternating the temperatures will alter the substitution of the leaving groups, thus forming a polymer backbone of gradient characteristics. Initial reactions to determine the relative rates of displacement of the chlorine and fluorine atoms were carried out using a model compound, 1, which possessed the chlorine and fluorine leaving groups, but not the phenol …

Evanescent Microwave Microscopy Of Porcine Skin Tissue, Richard A. Kleismit

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This thesis describes the application of a custom designed λ/4 resonant coaxial probe to measurements of the complex permittivity of in vitro freshly excised porcine skin tissue. The dielectric properties of the organic material within the near field of the tip of the probe frustrates the electric field and measurably changes the resonant frequency and quality factor Q of the coaxial sensor, where the change in resonant frequency and quality factor of a tuned resonance is measured as a function of tip-sample separation. The design of the probe enables better spatial resolution than previously developed probes. The following studies were …

Performance And Complexity Co-Evaluations Of Mpeg4-Als Compression Standard For Low-Latency Music Compression, Isaac Kevin Matthew

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In this thesis compression ratio and latency of different classical audio music tracks are analyzed with various encoder options of MPEG4ALS. Different tracks of audio music tracks are tested with MPEG4-ALS coder with different options to find the optimum values for various parameters to obtain maximum compression ratio with minimum CPU time (encoder and decoder time). Optimum frame length for which the compression ratio saturates for music audio is found out by analyzing the results when different classical music tracks are experimented with various frame lengths. Also music tracks with varying sampling rate are tested and the compression ratio and …

Electrochemistry Of Trinuclear Metal Clusters Of Molybdenum And Tungsten In 1-Ethyl-3- Methylimidazolium Tetrafluoroborate, Tracey Lynn Harris

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The imidazolium based ionic liquid: 1-ethyl-3-methylimidizoliumtetrafluoroborate, (EMIBF4) was synthesized to be used as a solvent for the electrochemical investigation of molybdenum and tungsten. The electrochemical window is about 4.2V after removing traces of impurities such as Cl^- and H₂O. Electronic spectra of metal clusters [Mo₃O₂(O₂CCH₃)₆(H₂O)₃]⁺² ; [W₃O₂(O₂CCH₃)₆(H₂O)₃]⁺² ; [MoW₂O₂(O₂CCH₃)₆(H₂O)₃]⁺² and [Mo_{2 …}

Poly(Arylene Ether)S With Truly Pendant Benzene Sulfonic Acid Groups, Mohamed Moustafa Abdellatif

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A series of new sulfonated poly(arylene ether)s containing one sulfonic acid group, located on a pendant phenyl sulfonyl moiety, at every repeat unit was synthesized using 3-sulfonated-3', 5'-difluorophenyl Sulfone, 4, and a variety of bisphenols. A conventional nucleophilic aromatic substitution (NAS) was utilized for the homopolymerization and copolymerization reactions. Polymerization reactions of 4 in NMP at 180 °C provided the corresponding linear sulfonated poly(arylene ether)s, s-PAEs, with number average molecular weight, M_n, ranging from 10,000 to 38,000 Daltons. All of the polymers were characterized by ¹H and ¹³C NMR spectroscopy, thermogravimetric analysis (TGA), and differential scanning …

Model And Solution Approaches For The Equipment Scheduling Under Disruption Problems In Usps Mail Processing And Distribution Centers, Arvindkumar Ravi Chakravarthy

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This research addresses the equipment scheduling problem under disruptions in United States Postal Service mail processing and distribution centers. These facilities contain a large variety of equipment and employ a non-homogeneous workforce that work on shifts of various lengths and start times. The scheduling of equipment (the determination of the configuration and usage of equipment to match mail arrivals) and the scheduling of workforce (the determination of the optimal size and composition of the workforce, their days off / lunch assignments, and overtime usage) to meet processing service commitment with a constantly changing demand are some of the most challenging …

Geologic Mapping Of The Changgo Dome In Southern Tibet Using Aster Imagery, Andrew Paul Folfas

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Within the thick TSS, south of the Indus-Tsangpo Suture, a series of granitic intrusions and gneissic domes crop out along the NHA. These culminations are common features that are seen in orogenic belts; therefore, understanding the nature and development of these features is an integral part of this study and other collisional orogenic studies. Changgo Dome is a granitic dominated feature that is characterized by the presence of two spectrally similar Tertiary granites. This zone is nearly inaccessible for ground mapping, thus it is an ideal setting for the use of satellite imagery as a cartographic medium. In a previous …

A Stochastic Production Planning Model Under Uncertain Demand, Meenakshi Prajapati

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Production planning plays a vital role in the management of manufacturingfacilities. The problem is to determine the production loading plan consisting of the quantity of production and the workforce level - to fulfill a future demand. Although the deterministic version of the problem has been widely studied in the literature, the stochastic production planning problem has not. The application of production planning models could be limited if the stochastic nature of the problem, for example, uncertainty in future demand, is not addressed. This study addresses such a stochastic production planning problem under uncertain demand and its application in an enclosure …

Dynamic Characterization Of A Pneumatic Muscle Actuator And Its Application To A Resistive Training Device, Jennifer L. Serres

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Research described in this dissertation expands the use of a biomechanical phenomenological model to a commercially available pneumatic muscle actuator (PMA). Due to the nonlinearities of the device, achieving accurate control is challenging. Experiments have been conducted that define boundaries of operation where linear approximations can be used to describe the dynamics of the PMA. Empirical data presented in this dissertation show that nonlinearities exist more prevalently at higher loads (on average >70% contractile force value). When the PMA is under high loads, low displacement occurs. Therefore, these regions are of less interest to design engineers. Once conditions of nonlinearities …