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Title: A design for the Hocking Valley power project
Creator: Burris, Edward, Deering, John J., Mammes, Harry A, Sullivan, Thomas F
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/designforhocking00burr
Thesis (B.S.)--Armour Institute of Technology;Includes folded leaves in back pocket

Title: The design and equipment of a metallographic polishing machine
Creator: Hallett, John A.
Date: 2009, 1921
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/designequipmento00hall
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 18

Title: PHOTOCATHODE TUNABILITY: THE PHOTOEMISSIVE PROPERTIES OF ULTRA-THIN MULTILAYERED MgO/Ag/MgO FILMS SYNTHESIZED BY PULSED LASER DEPOSITION
Creator: Velazquez, Daniel Gomez
Date: 2015, 2015-05
Description: Much of the early development of photocathode materials was aimed at the growth of photoemissive thin films with low work function, and high...
Show moreMuch of the early development of photocathode materials was aimed at the growth of photoemissive thin films with low work function, and high quantum efficiency (QE). It has been shown, both theoretically and experimentally, that metal-insulator junctions can lead to the modification of the work function and QE for coverages of a few monolayers of metal oxides on metallic substrates. However, the production of electron beams suitable for new photoinjector technologies in many instances requires low emittance beams from the cathode itself. Often the cathode intrinsic emittance plays an important role in new e-gun designs. A demonstration of the ability to control photoemissive properties by engineering the band structure of a photocathode could provide a pathway to meet the demands of new photoinjector technologies. Nemeth et al. [Phys. Rev. Lett. 104, 046801 (2010)] used density functional theory (DFT) to model the properties of a multilayered structure of MgO/Ag(001)/MgO with 4 monolayers of Ag(001) flanked by n monolayers (ML) of MgO. Their model indicated that it is possible to reduce the emittance of a photoemitted electron beam when the thickness n of the MgO layers is 2 or 3 monolayers because the surface band structure exhibits a narrowing of the density of occupied states in momentum near the Γ-point neighboring the Fermi Level. The theoretical prediction concerning the emission properties of these multilayers structures was tested by fabricating them, and then characterizing their emission properties. Synthesis of multilayered MgO/Ag/MgO films was performed using a custom-built pulsed laser deposition (PLD) system. In-situ growth monitoring was carried out by Reflection High-Energy Electron Diffraction (RHEED). Ex-situ techniques such as Scanning Tunneling Microscopy (STM), Scanning Electron Microscopy/Energy Dispersive Spectroscopy (EDS) and Photoelectron Spectroscopy (PES) were used to show the formation of the crystalline and chemical structure of the multilayered films. A Kelvin Probe/photocurrent-detector system, custom-built for this research, was used to measure the work function and QE of the samples. Angle Resolved Photoelectron Spectroscopy was used to measure the angular photoelectron yield. Simultaneous reduction of work function and increase of QE was observed for (001) oriented multilayers of various thicknesses with respect to that of a bare Ag/MgO(001) surface. Work function measurements of multilayers of various thicknesses in the (111) orientation also registered a monotonic reduction with respect to that of a bare Ag/Si(111) surface. Angular emission was compared for a MgO/Ag/MgO multilayer (thicknesses of 3 ML/4 ML/3 ML) sample and Ag/MgO(001). Emission analysis of the angle-resolved photoelectron spectra shows a net change in the angular emission with high kinetic energy electron density shifted toward surface-normal emission. Experimental results were consistent with theoretical predictions, which open the promising possibility of customizing emission properties by direct manipulation of the surface band structure of the emitter.
Ph.D. in Physics, May 2015
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Title: INTEGRATION OF DAYLIGHT IN THE COMMERCIALLY USED BUILDINGS FOR ENERGY SAVING PURPOSES
Creator: Tabibzadeh, Meysam
Date: 2014, 2014-07
Description: The integration between different building systems’ operation in response to various room and weather conditions has a direct positive effect...
Show moreThe integration between different building systems’ operation in response to various room and weather conditions has a direct positive effect on buildings energy performance and cost effectiveness. A Building Automation System (BAS) or an integrated Building Energy Management System (BEMS) typically control five major building systems, including people occupancy detection, shading control, HVAC, and lighting systems. Other building systems and internal energy loads also need to be considered when developing integrated controls and energy efficiency in office buildings. The controls are designed to operate in different building zones (lighting and thermal), while communicating with the main building management system. Whether the zone is being occupied or not will define further actions by other control components. The main goal of this research is to improve energy performance in commercial office buildings by developing the integration between various building controls and the use of natural light indoors and outside views while maintaining both the occupants’ visual and thermal comfort and high building energy performance at the same time. In this research, the proposed synchronization between building occupancy, daylighting, and integrated controls for various building systems in a commercial office space was assessed using computer simulations. The study uses Microsoft Excel as the primary database and result compiling platform. The work flow algorithm of the integrated control (in Visual Basic Application for Excel) automatically defines the new simulation criteria, makes adjustments in the simulation inputs, and runs DOE2.2 energy simulations for the proposed models with integrated controls as well as the baseline model (compliant with the ASHRAE 90.1-2010 standard) for further analysis. The simulations are conducted for eight simulation dates over five years. The results from the proposed model are analyzed and compared with the baseline results in order to evaluate its energy performance and to determine possible savings. The simulation results analysis determines how the implementation of the proposed system can improve the daylighting and energy performance in the building by maximizing the integration between different building systems controls in response to different parameters, such as occupancy, weather conditions, and daylight. The evaluated results of the proposed system are summarized as the system and sub-system algorithms, features, and components of each system, and, finally, as the design guidelines for implementation of the new fully integrated controls for commercial office buildings. From the evaluation of the proposed system performance, the list of research outcomes and deliverables will be concluded, by determining the impact of integrated controls on the overall energy performance of the office work space. The fact that if and when the energy efficiency and improved comfort and environmental quality work hand in hand, in addition to and the role of integrated occupancy in improving the energy efficiency will define the level of success for the proposed control system. The final research outcome is the development of the integrated workflow that can be used in new Building Automation Systems (BAS) or incorporated into the simulation engine for “Simulation Assisted” (see section 2.2.2) Building Energy Management Systems (BEMS).
Ph.D. in Architecture, July 2014
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Title: PREDICTING COMMENT QUALITY ON NEWS WEBSITES: LINGUISTIC INDICATORS AND VIEWS FROM JOURNALISM PROFESSIONALS
Creator: Scott, Edward Blake
Date: 2014, 2014-07
Description: As the web has become more interactive in recent years, with website users having the ability to generate their own content, there has been...
Show moreAs the web has become more interactive in recent years, with website users having the ability to generate their own content, there has been increased tension between the content generated by users and the content generated by “professionals,” especially professional journalists and publishers. Many journalism professionals see the value of allowing users to comment on their work; for example, an interactive site that allows user commenting may increase users’ loyalty to the site, meaning they will return often, generate page views, and increase advertising revenue. Users can also serve to further explore an issue discussed in an article by broadening the discussion to include the viewpoints of those who aren’t professional journalists. However, publishers of news site comments have noted many problems with introducing user-generated content (UGC) to their sites, including the fact that users sometimes post inflammatory, insensitive, or lowquality comments that do not serve to improve the experience of the average reader. The problems caused by these kinds of comments have increased the amount of time and money required to moderate the comments section. Beyond inflammatory comments, however, is the problem of highlighting very good or high-quality comments. What is the degree to which those high-quality comments can be discovered through an automated process? This dissertation sought to test the extent to which comments to news sites can be automatically evaluated for quality by using a text-analysis system. Journalists were interviewed to get their views on user comments in general and comment quality in particular. The data from these interviews was used to generate hypotheses about which linguistic metrics provided by Coh-Metrix, a web-based text-analysis system, might be xiii most indicative of comment quality as described by journalists. Finally, a content analysis and close reading of a sample of news site comments was conducted in order to describe news site comments as a writing genre. Results from the interviews indicated that comment length, comment syntax, comment cohesion, comment narrativity, and comment individuality were all indicative of comment quality. However, statistical analyses on a sample of 246 comments failed to produce significant results for linguistic metrics hypothesized to be indicative of quality. Alternatively, an “positive engagement score” scale was created and used to identify how “engaging” comments were; this scale showed to have a significant, though minor, positive relationship with the number of recommendations a comment received from readers. Finally, the genre analysis of the sample of news site comments revealed that comments in the sample share a communicative purpose of providing additional content related to the article under discussion, providing a practical value for journalists and other professionals by offering tips and fact-checking functions, and providing a space where readers can debate the article in question and begin to develop a sense of community.
Ph.D. in Technical Communication, July 2014
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Title: OPTIMAL ROUTING ALGORITHMS IN ENERGY-HARVESTING WIRELESS SENSOR NETWORKS
Creator: Martinez, Gina
Date: 2014, 2014-12
Description: Harnessing energy from environmental sources such as solar and wind is an attractive solution to the critical energy limitation problem in...
Show moreHarnessing energy from environmental sources such as solar and wind is an attractive solution to the critical energy limitation problem in wireless sensor networks. Energy harvesting can potentially provide the network with perpetual and sustainable operation, or it can prolong network lifetime even for high consumption applications so as to justify the high cost of deployment. However, in order to efficiently utilize harvested energy, the energy source dynamics need to be incorporated into the network design. One way to do so is to make the network layer routing algorithm energy-harvest-aware. One common property of environmental energy sources is that they are generally only intermittently available. To address this, a storage unit such as a rechargeable battery can be introduced into the system. However, this is only a partial solution due to finite buffer storage capacities that cause harvested energy to be wasted when full. In this work, we aim to maximize the network lifetime by optimizing the energy availability and consumption alignment. To realize this objective, we first show that the minimization of energy wastage is a necessary condition to the maximization of available network energy. We then propose an on-demand routing algorithm that maximizes the total residual network energy by minimizing the energy consumption and wastage. Next, we illustrate the tradeoff between the two objectives of maximizing the total network energy and maximizing the minimum network energy in prolonging network lifetime. Then, we propose a linear-programming routing solution that maximizes a utility objective function based on this tradeoff. Although these routing approaches are shown to achieve high energy utilization, they are still based on deterministic harvest and consumption models. In the last part of this work, we propose a routing algorithm by applying the Semi-Markov Decision Process. Using this method, we are able to incorporate a comprehensive consideration of stochastic solar availability and traffic models, heterogeneous network properties such as non-uniform energy buffer capacities and consumption rates, and the optimization of an analytical formulation for network lifetime.
Ph.D. in Electrical and Computer Engineering, December 2014
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Title: DESIGN AND OPTIMIZATION OF CONFIGURABLE PASSIVE COMPONENTS FOR CMOS MILLIMETER-WAVE INTEGRATED CIRCUITS
Creator: Liu, Gui
Date: 2011-05-10, 2011-05
Description: With the rapid growth of wireless communications, there is an increasing demand for low cost, low power consumption, high data rates and high...
Show moreWith the rapid growth of wireless communications, there is an increasing demand for low cost, low power consumption, high data rates and high density integrated circuits. The continuous scaling of CMOS technologies promises to achieve higher frequencies of operation in the millimeter-wave (mm-wave) frequency regime. To enable lager bandwidth for higher data rates wireless applications, many efforts have been focused on the design of mm-wave CMOS integrated circuits. The emerging mm-wave wireless commercial applications such as Wireless Hi-definition Video (60 GHz), automotive radar (77 GHz) and mm-wave imaging system (94 GHz) have brought new challenges in devices technology and systems. There is an ever increasing demand for multi-band and multi-mode integrated wireless communication systems which have the advantages of power and area savings. Therefore, flexible and configurable mm-wave on-chip components and circuits are needed to accommodate a wide variety of wireless communication standards. On the other hand, the first silicon success of the challenging mm-wave integrated circuits requires superior and robust design capabilities in cutting-edge technologies. To satisfy customers by providing them with the fastest time-to-market and the lowest total cost, the configurable multiband mm-wave solution is preferred. Design of on-chip passive components operating at millimeter wave frequencies presents several challenges due to the ohmic loss, parasitic inductance and capacitance. Therefore, it requires both an accurate model and electromagnetic (EM) simulation tools to characterize the passive components. The other challenge of design of mm-wave on-chip passives is process variations which can have a significant effect on the robustness of the passive components and circuits. Methodology to compensate and adjust for process variations is needed. Passives that can be configured after fabrication would be an attractive way to obtain accurate parameters and overcome effects of process variations. The configurable Multilayer Coplanar Waveguide (MCPW) based transmission lines offer convenient method to alleviate the problem of process variations and obtain accurate inductor values. This dissertation focuses on the design of mm-wave passive components and their applications. Model, EM simulation, and optimization of several novel MCPW-based configurable inductors are presented. A 77-GHz voltage controlled oscillator (VCO) and a 77-GHz receiver employing the configurable inductors have been realized. The 77-GHz VCO with MCPW-based configurable inductor exhibits low phase noise and wide frequency tuning range. The 77-GHz receiver achieves low power and state-of-the-art performance. The successful implementations of several individual configurable passive components, a 77-GHz VCO, and a 77-GHz receiver demonstrate the feasibility to achieve good performance and robust design with configurable passive components.
Ph.D. in Electrical Engineering, May 2011
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Title: THE POLYMORPHIC DIAGRAM: CONCEPTS FOR DESIGN TECHNOLOGY TO MODEL SPATIAL CRITERIA IN ARCHITECTURE DESIGN
Creator: Hamadah, Qutaibah
Date: 2012-11-03, 2012-12
Description: In Architectural design, reasoning about space and its configuration lies at the center of the conceptual design workflow. The process unfolds...
Show moreIn Architectural design, reasoning about space and its configuration lies at the center of the conceptual design workflow. The process unfolds in a reflective and adaptive modeling methodology, through which architects structure their understanding of the design problem, and mediate its responsive and sensitive resolution. Paradoxically, however, modeling and representing spatial information – knowledge about the design problem’s spatial requirements and its relational orders – is perhaps the least welldeveloped feature in modern design systems. With all its importance in architecture design, existing design technology offers only limited assistance to one of architecture’s most critical and difficult design workflows, the definition of space, its layout and configuration. Moving forward, modern design systems must extend their ability to assist the architect in modeling spatial and relational design criteria. They must profit an integrated workflow where the problem definition, and the solution proposition develop in unison. In particular, it should pay heed to the architect’s cognitive and generative parameters, which necessarily relies on an adaptively and reflective modeling workflow, one that bridges between the problem definition and its solution proposition using multiple forms of representation. Towards this end, this dissertation presents the Polymorphic Diagram: a concept for a design technology to assist the architect in modeling spatial and relational design criteria using an interactive, graph-based, multi-representational medium.
PH.D in Architecture, December 2012
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Title: A LONGITUDINAL STUDY OF POSTTRAUMATIC SYMPTOMS AND POSTTRAUMATIC GROWTH IN ONCOLOGY PATIENTS
Creator: Thilges, Sarah R
Date: 2013, 2013-07
Description: Cancer has been observed and studied within the development of both posttraumatic stress disorder (PTSD) and posttraumatic growth (PTG)...
Show moreCancer has been observed and studied within the development of both posttraumatic stress disorder (PTSD) and posttraumatic growth (PTG) although reported prevalence rates of PTSD vary greatly and PTG rates are even less established. The current longitudinal study seeks to elucidate which factors are related to endorsing PTSD and PTG symptoms among oncology patients. One hundred and twenty-five patients completed measures at Time 1 assessing rates and predictors of PTSD and within the same sample, 75 patients completed measures assessing rates and predictors of PTG four years later (Time 2). A model containing utilization of venting along with greater trauma impact ratings significantly predicted PTSD symptoms at Time 1, although none of the variables were independent significant predictors. At Time 2, results indicate using spirituality as support and greater obsessive and depressive symptoms at T1 predicted PTG although only spirituality was a significant independent predictors. Results have implications for clinical and research work to address and monitor potential risk factors for distress and strengths which may promote PTG.
PH.D in Psychology, July 2013
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Title: ANTI-STIGMA PROGRAMS: STIGMA IN CAMPUS POlICE OFFICERS
Creator: Rafacz, Jennifer D.
Date: 2012-07-19, 2012-07
Description: It has been proposed that the most effective way to combat mental illness stigma is to focus on power groups who have a direct impact on the...
Show moreIt has been proposed that the most effective way to combat mental illness stigma is to focus on power groups who have a direct impact on the lives of persons with serious mental illness. With the increase of violence and need for mental health services on college campuses, campus police officers are seen as an important power group for persons with serious mental illness. This study assessed the effects of online contact versus online education anti-stigma programs on campus police officers attitudes toward persons with serious mental illness. The study also considered moderators of contact specifically level of familiarity, state empathy, and trait empathy. It was found that the online program was not effective in changing attitudes. The research also suggested that the attitudes of the campus police officers were generally non-stigmatizing other than the endorsement of fear/danger. Both state and trait empathy were found to be moderators helping behaviors and social distance. Level of familiarity was not found to be a moderator of social distance. The findings suggest that future research and stigma work with campus police officers should focus on in vivo behaviorally driven interventions such as crisis intervention training with a focus on danger/fear.
Ph.D. in Psychology, July 2012
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Title: A COMPARISON OF META-ANALYTIC PROCEDURES WHEN PRE- AND POSTTEST VARIANCES ARE HETEROGENEOUS
Creator: Collins, Michael W.
Date: 2011-11, 2011-12
Description: Meta-analysis is a statistical method for aggregating summary results from archival research. Traditional meta-analysis procedures that...
Show moreMeta-analysis is a statistical method for aggregating summary results from archival research. Traditional meta-analysis procedures that involve repeated measures assume homogeneous variances in pretests and posttests, an assumption which is often violated in training evaluation contexts due to variance inflation in posttests. A new meta-analytic procedure that allows for heterogeneous variance in pretests and posttests was tested in the context of leadership and managerial training programs. Application of the new method revealed greater sampling variance and less between-study variance than traditional meta-analysis with little effect on estimation of the mean effect size. However, the procedure screened out a large number of studies due to the intensive data requirements, which limited the number of usable studies for the meta-analysis.
Ph.D. in Psychology, December 2011
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Title: FROM FIREPLACE TO STEAM: DOMESTIC HEATING TECHNOLOGY IN NORTHEASTERN UNITED STATES, 1840-1890
Creator: Morais, Caroline
Date: 2012-12-07, 2012-12
Description: Why study nineteenth-century domestic heating technology? Besides its pop- ular appeal and utilitarian value, domestic heating technology is...
Show moreWhy study nineteenth-century domestic heating technology? Besides its pop- ular appeal and utilitarian value, domestic heating technology is one of the most signi cant yet least explored subjects in American history. American processes of industrialization, manufacturing, and transportation are well known, however, the impact of technological changes on the home is less familiar. Understanding past everyday lives is crucial to recognize the processes of adjusting to new technologies, particularly those technologies essential to today's American lives that have been overlooked. This dissertation examines the shift in domestic heating modes in North- eastern United States between the decades of 1840 and 1890. After carefully reviewing the literature on the subject of nineteenth-century heating technology, I asked myself why the domestic setting has received little schol- arly or historical attention in comparison to those of industrial and commercial set- tings. The answer lies on the fact that, traditionally, historians have been more interested in public events than in those within the private environment. The signi - cance of domestic heating technology has also been reduced duo to divisions between scholarly elds and disciplines. Also, the interpretation of artifacts has been more the eld of anthropologists than that of historians. Thus, few studies have narrowed their focus to a speci c topic of technology and the di erences in form, function, and cultural settings of its development. Investigating a historically obsolete technology and understanding the way people used it can be challenging. Domestic heating technology has advanced, and attitudes towards it have changed over time. It has been di cult to nd physical evidence of early examples in the form in which people originally used it daily. Addi- tionally, few people took the time to record their everyday-life interactions with the equipment and actual models of the old technology are hard to nd. Mid-nineteenth iv century American household heating apparatuses are a clear example of that. The ine ciency of systems previous to central heating challenged inventors and manufac- tures to search for and invest in more convenient and economical options to improve the quality of life. With the development of household heating technology, people gradually abandoned replaces and stoves and adopted furnaces and central heating as their primary source of heating. My goal was to explore the evolving meaning of domestic heating systems as a technological symbol. By analyzing the changing responses from one technological development to the other, I was able to identify some main points that made appro- priate domestic heating and ventilation a necessity for both comfort and health of Americans who lived in the focused period. I chose the ve decades between 1840 and 1890 because most of the modern conveniences were introduced into American homes for the rst time during those years and for their signi cance to the country's technological history. The Northeastern region was chosen as the geographical focus because the dispersion of knowledge began there, especially knowledge in heating and ventila- tion technology and apparatus manufacturing. The sources for the study included domestic advice manuals, architectural pattern books, engineering and architectural periodicals, patent records, manufacturers' and dealers' sales catalogs, and census schedules. The technological development of heating and ventilation systems culmi- nated with the advent of central heating, which currently represents the technology of domestic heating methods. In the design of American homes, central heating systems have superseded previous apparatuses such as replaces and stoves. They have become an option rather than a necessity of a comfortable and convenient domestic life. This disserta- tion is a brief study of that moment of transition. My intention was to expand on v basic assumptions about the technological development of the American home, not to challenge them. There has already been a considerable amount of attention given to the study of the American home and home life. Therefore, I see my research as an addition to the growing knowledge of the history of American domestic technology and the people and innovations that enabled its development.
PH.D in Philosophy in Architecture, December 2012
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Title: HARDWARE-EFFICIENT VLSI IMPLEMENTATION FOR PARALLEL LINEAR-PHASE DIGITAL FIR FILTER
Creator: Tsao, Yu-chi
Date: 2011-11, 2011-12
Description: Along with the explosive growth of multimedia applications, the number of gates required and the area consumed in very-large-scale integration...
Show moreAlong with the explosive growth of multimedia applications, the number of gates required and the area consumed in very-large-scale integration (VLSI) for digital signal processing (DSP) is getting higher and higher. Therefore, the demand for low-complexity and low-cost VLSI architectures for DSP, which occupies area as small as possible while remaining high performance, is imperatively needed. Finite impulse response (FIR) digital filter is one of the most widely used fundamental devices performed in DSP systems, ranging from wireless communications to video and image processing. Furthermore, when narrow transition band characteristics are required, the much higher order in the FIR filter is unavoidable. For instance, a 576-tap digital filter is used in video ghost canceller for broadcast television, which reduces the effect of multi-path signal echoes. On the other hand, parallel and pipelining processing are two techniques used in DSP applications, which both can be exploited to reduce the power consumption. Parallel processing applied on FIR digital filter can either increase the throughputs for high-speed processing or reduce the power consumption of the original sequential filter by lower supply voltage. Hence, there have been several architectures for parallel FIR digital filter proposed in the past. However, for symmetric convolutions, linear phase digital FIR filter, these proposed architectures are not beneficial in terms of hardware consumption. In this dissertation, new parallel FIR digital filter architectures which can save significant hardware cost by exploiting the inherent nature of symmetric convolutions, namely linear phase digital FIR filter, are presented. This dissertation is mainly divided into four chapters. In chapter one, some prerequisites as the background related to parallel finite impulse response (FIR) digital xi filter design and implementation are introduced, including conventional parallel FIR digital filter architectures, parallel FIR digital filter structures based on fast FIR algorithm (FFA), previously proposed architectures for parallel FIR filter, maximum absolute difference (MAD) quantization algorithm, canonic signed digit (CSD) representation and CSD multipliers for constant multiplications, are introduced and reviewed. In chapter two, the proposed parallel FIR digital filter structures for symmetric convolutions of even length are presented, in which the complexity and experimental results are analyzed and compared with FFA-based parallel FIR digital filter and other previously proposed structures. In chapter three, the proposed parallel FIR digital filter architectures for symmetric convolutions of odd length are presented, in which the complexity and the benefit of structures are analyzed and compared with FFA-based parallel FIR digital filter and other previously proposed structures The last chapter, chapter four, gives the summary and the conclusion of the proposed parallel linear-phase FIR digital filter.
Ph.D. in Electrical Engineering, December 2011
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Title: PARTICLE FILTERING ESTIMATION APPROACH IN ADVANCED DIGITAL COMMUNICATION SYSTEMS
Creator: Huang, Lun
Date: 2013, 2013-05
Description: The ever-increasing volume of users and the demand for more communication services bring about many advanced modulation and demodulation...
Show moreThe ever-increasing volume of users and the demand for more communication services bring about many advanced modulation and demodulation technologies which are developed to increase the spectrum efficiency and cope with challenging transmission conditions in digital communications. However, it is difficult to improve the performance of those traditional modulation and demodulation approaches without increasing transmit power and lowering spectrum efficiency. This thesis studies the application of powerful Particle Filtering methods to the problems associated with the interference cancellation, equalization, demodulation, and decoding of the signals over communication channel. In this thesis, theoretic models of using particle filtering approaches in digital communications are investigated, and several specific algorithms and schemes are considered as applications of the theoretic models. First, the application of particle filtering in delayed decision feed-back sequence estimation equalization is addressed. The particle filtering approach is then introduced to an efficient particle filtering receiver for inter-carrier interference cancellation and demodulation of M-ary modulated signals in OFDM/OFDMA system under time-variant Rayleigh fading channels. Subsequently, an efficient sequential Monte Carlo (SMC) demodulation approach for Polynomial Phase Modulation (PPM) is discussed. The interference cancellation and demodulation algorithm for MIMO-PPM scenario is then derived. The analysis of performance and computational complexity for SMC particle filtering approach is also provided. Comprehensive simulation results confirm that the proposed sequential Monte Carlo particle filtering approaches have better performance than the conventional methods.
PH.D in Electrical Engineering, May 2013
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Title: EXPANDING FAITH-BASED ORGANIZATIONS’ ADAPTATION OF STREAMING TECHNOLOGY
Creator: Johnson Winston, Patty D.
Date: 2011-07-18, 2011-05
Description: In the field of technical communication there exist few studies that specifically address faith-based organizations’ use of communication...
Show moreIn the field of technical communication there exist few studies that specifically address faith-based organizations’ use of communication technology. The purpose of this dissertation was to show how these organizations can expand their use of streaming technology by using principles and practices that are common in technical communication. This was addressed in three phases. First, a review of the relationship between religion and media was conducted. It revealed that faith-based organizations are early adaptors of communication technology. Communication technology is used to widely broadcast their organizational missions, tenets and goals. By accomplishing these tasks, faith-based organizations seek to educate and reinforce cultural norms, images, and belief systems among their adherents and attract new members. Second, an examination of theories and instructional practices found in technical communication was conducted. It was determined that adapting a learning-centered approach to instruction can be applied to a distance education model for faith-based education. Third, faith-based websites were analyzed to determine types and current uses of communication technology. It was established that most of the organizations that offer educational courses do not conduct them online, even if they already use streaming media for other purposes. The findings suggest that faith-based organizations’ use of streaming technology for educational purposes is an area of inquiry that should be further explored by technical communicators. Technical communication provides a rich array of disciplines from which to draw, such as Instructional Design, Information Architecture, and Usability.
Ph.D. in Technical Communication, May 2011
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Title: FINITE ELEMENT ANALYSIS OF HIGH HEAT LOAD DEFORMATION AND MECHANICAL BENDING CORRECTION OF A BEAMLINE MIRROR FOR THE APS UPGRADE
Creator: Goldring, Nicholas
Date: 2017, 2017-07
Description: The impending Advanced Photon Source Upgrade (APS-U) will introduce a hard x-ray source that is set to surpass the current APS in brightness...
Show moreThe impending Advanced Photon Source Upgrade (APS-U) will introduce a hard x-ray source that is set to surpass the current APS in brightness and coherence by two to three orders of magnitude. To achieve this, the storage ring light source will be equipped with a multi-bend achromat (MBA) lattice [1]. In order to fully exploit and preserve the integrity of new beams actualized by upgraded storage ring components, improved beamline optics must also be introduced. The design process of new optics for the APS-U and other fourth generation synchrotrons involves the challenge of accommodating unprecedented heat loads. This dissertation presents an ex-situ analysis of heat load deformation and the subsequent mechanical bending correction of a 400 mm long, grazing-incidence, H2O side-cooled, reflecting mirror subjected to x-ray beams produced by the APS-U undulator source. Bending correction is measured as the smallest rms slope error, σrms, that can be resolved over a given length of the heat deformed geometry due to mechanical bending. Values of σrms in the <0.1 µrad regime represent a given mirror length over which incident x-ray beams from modern sources can be reflected without significant loss of quality [2, 3]. This study assumes a perfectly flat mirror surface and does not account for finish errors or other contributions to σrms beyond the scope of thermal deformation and elastic bending. The methodology of this research includes finite element analysis (FEA) employed conjointly with an analytical solution for mechanical bending deflection by means of an end couple. Additionally, the study will focus on two beam power density profiles predicted by the APS-U which were created using the software SRCalc [4]. The profiles account for a 6 GeV electron beam with second moment widths of 0.058 and 0.011 mm in the x- and y- directions respectively; the electron beam is passed through a 4.8 m long, 28 mm period APS-U undulator which produces the x-ray beam incident at a 3 mrad grazing angle on the flat mirror surface for both cases. The first power density profile is the most extreme case created by the undulator at it’s closest gap with a critical energy of 3 keV (ky=2.459); the second profile is generated for the case in which the undulator is tuned to emit at 8 keV (ky=1.026). The 3 keV case is of particular interest as it represents one of the most intense peak heat loads predicted to be incident on first optics at the APS-U. The FEA results revealed that the deflection due to the 3 keV heat load yields a 10.9 µrad rms slope error over the full mirror length. The projected correction via the elastic bending of the substrate yields a 0.10 µrad σrms within the center longitudinal 300 mm. The FEA also predicts that the 8 keV heat load deflection can be corrected to a σrms of 0.11 µrad within the center 300 mm from 1.50 µrad over the entire length. Attempts to optimize the end couple to correct over the entire 400 mm mirror length were unable to resolve the heat load deflection rms slope error to within a < 0.1 µrad value for either case. However, if a larger corrected surface is required, a longer mirror can be implemented so as to absorb the heat load of a larger beam than necessary which can then be cut by an aperture to the desired size and energy range.
M.S. in Physics, July 2017
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Title: COORDINATED DRIVING IN CONNECTED AND AUTONOMOUS VEHICLE SYSTEM -- OPTIMAL ADVANCE LANE CHANGE ZONES AND COORDINATED PLATOON CAR FOLLOWING CONTROL
Creator: Gong, Siyuan
Date: 2017, 2017-07
Description: The connected and autonomous vehicle (CAV) system enables countless innovative coordinated driving approaches, such as coordinated lane change...
Show moreThe connected and autonomous vehicle (CAV) system enables countless innovative coordinated driving approaches, such as coordinated lane change and car-following in microscopic CAV control, and coordinated rounding and parking in macroscopic traffic flow guidance, which will improve the performance of our transportation system by enhancing traffic mobility, providing safe driving environment and reducing fuel consumption. Since the lane change and car-following behavior are indicated as crucial factors of traffic safety and efficiency, this dissertation focuses on developing the coordinated driving schemes in microscopic control and operation of lane change and car-following maneuvers. In particular, I develop an lane change zone optimization strategy and the coordinated platoon car-following control for a pure CAV platoon and a mixed platoon (i.e. mixed with human-drive vehicles and CAVs) respectively. This dissertation first explore the management strategy of the mandatory lane change near a two-lane highway off-ramp by optimizing the location of advance warning. The proposed approach considers that the area downstream of the advance warning includes two zones: the green and yellow zones corresponding to their respective most like lane change maneuvers. An optimization model is proposed to search for the optimal green and yellow zones. Traffic flow theory such as Greenshield model and shock wave analysis are used to analyze the impacts of the S-MLC and D-MLC maneuvers on the traffic delay. Numerical experiments indicate that the proposed optimization model can identify the optimal location to set the advance MLC warning nearby an off-ramp so that the traffic delay resulting from lane change maneuvers is minimized, and the corresponding capacity drop and traffic oscillation can be efficiently mitigated. Then, this research develops a novel car-following control scheme for a platoon of connected and autonomous vehicles on a straight highway. The platoon is modeled as an interconnected multi-agent dynamical system subject to physical and safety constraints. A constrained optimization based control scheme is proposed to ensure an entire platoon’s transient traffic smoothness and asymptotic dynamic performance. This dissertation develops dual based distributed algorithms to compute optimal solutions with proven convergence. Furthermore, the asymptotic stability of the unconstrained linear closed-loop system is established. These stability analysis results provide a principle to select penalty weights in the underlying optimization problem to achieve the desired closed-loop performance for both the transient and the asymptotic dynamics. By the motivation that CAVs and human-drive vehicles will co-exist on the road for a long period in the near future, the third part of this dissertation extends the pure CAV coordinated platooning control to the mixed flow environment. By integrating the Newell car-following model, a real-time curve matching algorithm is implemented to calibrate the ca-following model and anticipate the movement of human-drive vehicle by the real-time trajectory data. The constrained MPC are developed for each CAV platoon, considering their movement interaction through the human-drive vehicle platoon. Furthermore, this study provide a modified dual based distributed algorithm to improve convergence speed of the primal problem for the dual based distributed algorithm in Chapter 4. Several requirements of the penalty weights selection are provided by stability analysis under the unconstrained conditions. The numerical experiments based on field data will be conducted to illustrate the effectiveness and efficiency of the proposed the solution approach and the platoon control schemes.
Ph.D. in Civil Engineering, July 2017
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Title: INTEGRATED PLANNING OF BEV PUBLIC FAST-CHARGING STATIONS
Creator: Gong, Lin
Date: 2015, 2015-12
Description: This thesis proposes a multi-layer strategy and an abstract map method to achieve an integrated planning of public fast-charging stations to...
Show moreThis thesis proposes a multi-layer strategy and an abstract map method to achieve an integrated planning of public fast-charging stations to charge certain number of lightduty battery electric vehicles in a given geographic region under its existing environment, aiming to improve application of electric vehicle in the studied region and finally enhance social welfare in a long term by optimally locating public fast-charging stations and assigning their installed capacities to maximize the possibility of effectively charging battery electric vehicles, as well as to minimize the infrastructure cost and mitigate possible negative impacts on the transportation system and the electric power system. In the first layer of this multi-layer strategy, the conditions of the transportation system are considered, analyzed and mathematically modeled, while in the second layer, based on the former layer, the conditions of the electric power system are incorporated. Then in the third layer, an integrated planning of public fast-charging stations is achieved by combining both the transportation system's and the electric power system's conditions. From the first to the last layer, a case is studied in each layer to test the idea, method and also the mathematical model which is built by the MILP method. These works are based on an abstract road network map which is rooted in the actual map of a representative geographic region. After the optimal results based on the abstract map are obtained, they will be mapped back to the actual map of the representative geographic region. Therefore, the ideas, methods and solutions studied in this thesis aiming to achieve an integrated planning of public fast-charging stations to charge battery electric vehicles are able to be applied in practice.
M.S. in Electrical Engineering, December 2015
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Title: Graphical methods in reinforced concrete design
Creator: Klein, Samuel, Greifenhagen, E. O.
Date: 2009, 1909
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/graphicalmethods00klei
Thesis (B.S.)--Armour Institute of Technology

Title: DUAL-BASED APPROXIMATION ALGORITHMS FOR MULTIPLE NETWORK DESIGN PROBLEMS
Creator: Grimmer, Benjamin
Date: 2016, 2016-05
Description: We study a variety of NP-Complete network connectivity problems. Our pri- mary results come from a novel Dual-Based approach to approximating...
Show moreWe study a variety of NP-Complete network connectivity problems. Our pri- mary results come from a novel Dual-Based approach to approximating network de- sign problems with cut-based linear programming relaxations. This approach gives a 3=2-approximation to Minimum 2-Edge-Connected Spanning Subgraph that is equivalent to a previously proposed algorithm. One well-studied branch of network design models ad hoc networks where each node can either operate at high or low power. If we allow unidirectional links, we can formalize this into the problem Dual Power Assignment (DPA). Our Dual-Based approach gives a 3=2-approximation to DPA, improving the previous best known approximation of 11=7 1:57. Another standard network design problem is Minimum Strongly Con- nected Spanning Subgraph (MSCS). We propose a new problem generalizing MSCS and DPA called Star Strong Connectivity (SSC). Then we show that our Dual-Based approach achieves a 1.6-approximation ratio on SSC. As a result of our Dual-Based approximations, we prove new upper bounds on the integrality gaps of these problems. For completeness, we present a family of instances of MSCS (and thus SSC) with integrality gap approaching 4=3.
M.S. in Computer Science, May 2016
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