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1
Bay, Christoph. "Dynamic holographic masks for adaptive optical lithography." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609954.
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George, Jonathan Keith. "Polar Synthetic Imaging| Single Pixel Imaging with Rotating Spiral Masks." Thesis, The George Washington University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1566270.
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The use of spiral masks placed in front of a single pixel and rotated in time is investigated as a method of single pixel imaging. Single pixel imaging allows an image to be reconstructed from samples of a single pixel over time. This sampling has traditionally been accomplished with liquid crystal arrays or digital micromirror devices. A set of rotating spiral masks in the aperture offer an alternative solution that may reduce complexity and cost for some imaging applications.
3
Rathsack, Benjamen Michael. "Photoresist modeling for 365 nm and 257 nm laser photomask lithography and multi-analyte biosensors indexed through shape recognition." Access restricted to users with UT Austin EID, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3035170.
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Ma, Xu. "Generalized inverse lithography methods for phase-shifting mask design." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 38 p, 2007. http://proquest.umi.com/pqdweb?did=1338919391&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Levin, Marcy E. "The use of edge gradient analysis on chrome and emulsion photomasks to determine modulation transfer functions /." Online version of thesis, 1985. http://hdl.handle.net/1850/10148.
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Agrawal, Ankur. "Development and characterization of advanced electron beam resists." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/34054.
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Cheshmehkani, Ameneh. "Design and synthesis of molecular resists for high resolution patterning performance." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/50286.
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In this thesis, different approaches in synthesizing molecular resist are examined, and structure-property relations for the molecular resist properties are studied. This allows for design of resists that could be studied further as either negative or positive tone resists in photolithography. A series of compounds having different number of acrylate moiety, and different backbones were investigated for photoresist application. Thermal curing of acrylate compounds in organic solvent was also examined. Film shrinkage, as well as auto-polymerization was observed for these compounds that make them unsuitable as photoresist material. Furthermore, calix[4]resorcinarenes (C4MR) was chosen as backbone, and the functional groups was selected as oxetane and epoxy. Full functionalized C4MR compounds with oxetane, epoxy and allyl were synthesized. Variable-temperature NMR of C4MR-8Allyl was studied in order to get a better understanding of the structure’s conformers. Energy barrier of exchange (ΔG#) was determined from coalescence temperatures, and was 57.4 KJ/mol for aromatic and vinyl hydrogens and 62.1 KJ/mol for allylic hydrogens.
8
Mishra, Ritwik. "Photoresist development on SiC and its use as an etch mask for SiC plasma etch." Thesis, Mississippi State : Mississippi State University, 2002. http://library.msstate.edu/etd/show.asp?etd=etd-06162002-205803.
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Sinha, Ashwini K. "Design and Characterization of Materials and Processes for Area Selective Atomic Layer Deposition." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/19736.
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Area selective atomic layer deposition (ASALD) is demonstrated to be a promising route to perform direct patterned deposition. In particular, methods to modify (or mask) the surface and process parameters to perform selective deposition of titanium dioxide have been developed and investigated in detail. Results indicated that self assembled monolayer based masking methodology posses significant limitations due to challenges associated with obtaining defect free monolayer and absence of traditional patterning techniques. On the other hand, polymer films based masking methodology offer a better alternative to perform ASALD. A number of factors that must be considered in designing a successful ASALD process based on polymer films were identified. These include: reactivity of polymer with ALD precursor, diffusion of ALD precursors through polymer mask and remnant precursor content in the polymer film during ALD cycling. Investigations suggested that ALD nucleation can be successfully blocked on polymer films that do not contain direct OH sites in their backbone. It was observed that sorption of water in the polymer film does not pose a serious limitation however; metal precursor diffusion through the polymer mask was identified as a critical parameter in determining the minimum required masking layer thickness for a successful ASALD process. In addition, a novel ASALD-based top surface imaging (TSI) technique has been developed. The ASALD-TSI process has demonstrated sharp contrast (etch barrier deposition vs exposure dose) and therefore offers the potential to overcome many of the challenges experienced with conventional TSI schemes.
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Alabi, Taiwo Raphael. "Design of photomodifiable material systems for maskless patterning of functional ceramic and metallic materials at multiple length scales." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/51709.
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Silicon and silicon-based materials have been investigated for the fabrication of electronic, optoelectronic, solar, and structural/mechanical devices. To enable the continuous use of silicon-based materials for next generation device applications, new and inexpensive ways of fabricating features of silicon, and silica-based materials are needed. This dissertation investigates: 1) novel techniques for the fabrication of silica and silicon nanofeatures with potential application in the electronics and optoelectronics industry; 2) new designs of photomodifiable material systems (resists) for maskless patterning of silica filled composites for structural/mechanical applications. Sub-micron and nano-scaled features were fabricated onto silicon and silicon oxide substrates using a technique combining block copolymers and laser interference ablation. The sacrificial block copolymers are loaded with metallic salt precursors and patterned with a UV laser to generate device-oriented nanofeatures. New photopolymerizable material systems (negative tone resists) were developed based on curcumin photosensitizer and an epoxy-acrylate, vinylether, and vinylether-acrylate silica¬-loaded material systems. The cationic and radical mechanisms employed by the monomeric systems under a high vapor pressure mercury lamp source were investigated with several materials characterization techniques.
11
Arab, Hassani Faezeh. "Resonant nano-electro-mechanical sensors for molecular mass-detection." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/336335/.
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This research is conducted as a part of EU FP7 project entitled NEMSIC (hybrid nanoelectro-mechanical/integrated circuit systems for sensing and power management applications) with project partners, EPFL, TU Delft, IMEC-NL, CEA-LETI, SCIPROM, IMEC-BE, Honeywell Romania, and HiQSCREEN. Nano-electro-mechanical (NEM) sensors are getting an increased interest because of their compatibility with “In-IC” integration, low power consumption and high sensitivity to applied force, external damping or additional mass. Today, commercial biosensors are developed based on mass-detection and electro-mechanical principles. One of the recent commercial mass-detection biosensors is a quartz crystal microbalance (QCM) biosensor which achieves the mass sensitivity of a few tens pico g/Hz. The newly developed in-plane resonant NEM (IP R-NEM) sensor in this thesis achieves the mass sensitivity less than zepto g/Hz that is over nine orders smaller than that of the commercial QCM sensor using a much smaller sensing area compared to the QCM sensor. This fact will make the IP-RNEM sensor a world-unique sensor that shows a very high sensitivity to a very small change in mass. The stated mass sensitivity is achieved by modelling the functionalization and detection processes of the suspended beam. For modelling the linker molecules in the functionalization process, a conformal coating layer in different configurations are added to the suspended beam and the sparse distribution of target molecules in the detection process is modeled by changing the density of the coating layer. I would like to clarify that the scaling rule of the mass responsivity is given by k4 regardless of the different functionalization configurations. I develop a completely new hybrid NEM-MOS simulation technology which combines three-dimensional finite element method (3D FEM) based NEM device-level simulation and circuit-level simulation for NEM-MOS hybrid circuits. The FEM device-level simulation module also includes new modelling of selfassembled monolayer for surface functionalization as well as adsorb ed molecules to be detected and facilitates quantitative evaluation of mass responsivity of designed NEM sensor devices. The basic part of the sensor, the NEM structure, includes a suspended beam and two side electrodes and that is fabricated at the Southampton Nanofabrication Centre (SNC). The fabrication at SNC includes a new sensor that uses a free-free beam that improves the quality factor up to five orders of magnitude at room temperature and atmosphere based on the numerical results. The IP R-NEM sensor consists of a suspended beam that is integrated with an in-plane MOSFET and is fabricated by CEA-LETI. The monolithically integrated NEM with the MOSFET on the same SOI layer for the sensor is a real breakthrough which makes it a potential low-cost candidate among the mass-detection based sensors. With respect to the conducted radio-frequency (RF) characterization for nano-wire devices in collaboration with the Tokyo Institute of Technology and NEM structures, the designing of an RF contact pad to reduce the effect of parasitic frequencies and doing the measurement at high vacuum to reduce the motional resistance and increase the quality factor are necessary for the characterization of devices with nano-scale dimensions. The integrated MOSFET in the IP RNEM sensor amplifies the output transmission signal from the resonating beam by its intrinsic gain. The fabricated sensors show a three orders of magnitude larger gain than that of the previously proposed resonant suspended gate FETs by biasing the MOSFET at the optimized voltage biases that are found based on the DC characterization of MOSFETs.
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Lin, Tzu-Yung. "Advanced electronics for Fourier-transform ion cyclotron resonance mass spectrometry." Thesis, University of Warwick, 2012. http://wrap.warwick.ac.uk/55048/.
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With the development of mass spectrometry (MS) instruments starting in the late 19th century, more and more research emphasis has been put on MS related subjects, especially the instrumentation and its applications. Instrumentation research has led modern mass spectrometers into a new era where the MS performance, such as resolving power and mass accuracy, is close to its theoretical limit. Such advanced performance releases more opportunities for scientists to conduct analytical research that could not be performed before. This thesis reviews general MS history and some of the important milestones, followed by introductions to ion cyclotron resonance (ICR) technique and quadrupole operation. Existing electronic designs, such as Fourier-transform ion cyclotron resonance (FT-ICR) preamplifiers (for ion signal detection) and radio-frequency (RF) oscillators (for ion transportation/filtering) are reviewed. Then the potential scope for improvement is discussed. Two new FT-ICR preamplifiers are reported; both preamplifiers operate at room temperature. The first preamplifier uses an operational amplifier (op amp) in a transimpedance configuration. When a 18-k feedback resistor is used, this preamplifier delivers a transimpedance of about 85 dB , and an input current noise spectral density of around 1 pA/ p Hz. The total power consumption of this circuit is around 310 mW when tested on the bench. This preamplifier has a bandwidth of fi3 kHz to 10 MHz, which corresponds to the mass-to-charge ratio, m/z, of approximately 18 to 61k at 12 T for FT-ICR MS. The transimpedance and the bandwidth can be adjusted by replacing passive components such as the feedback resistor and capacitor. The feedback and bandwidth limitation of the circuit is also discussed. When using an 0402 type surface mount resistor, the maximum possible transimpedance, without sacrificing its bandwidth, is approximated to 5.3 M . Under this condition, the preamplifier is estimated to be able to detect ~110 charges. The second preamplifier employs a single-transistor design using a different feedback arrangement, a T-shaped feedback network. Such a feedback system allows ~100-fold less feedback resistance at a given transimpedance, hence preserving bandwidth, which is beneficial to applications demanding high gain. The single-transistor preamplifier yields a low power consumption of ~5.7 mW, and a transimpedance of 80 dB in the frequency range between 1 kHz and 1 MHz (m/z of around 180 to 180k for a 12-T FT-ICR system). In trading noise performance for higher transimpedance, an alternative preamplifier design has also been presented with a transimpedance of 120 dB in the same frequency range. The previously reported room-temperature FT-ICR preamplifier had a voltage gain of about 25, a bandwidth of around 1 MHz when bench tested, and a voltage noise spectral density of ~7.4 nV/ p Hz. The bandwidth performance when connecting this preamplifier to an ICR cell has not been reported. However, from the transimpedance theory, the transimpedance preamplifiers reported in this work will have a bandwidth wider by a factor of the open-loop gain of the amplifier. In a separate development, an oscillator is proposed as a power supply for a quadrupole mass filter in a mass spectrometer system. It targets a stabilized output frequency, and a feedback control for output amplitude stabilization. The newly designed circuit has a very stable output frequency at 1 MHz, with a frequency tolerance of 15 ppm specified by the crystal oscillator datasheet. Within this circuit, an automatic gain control (AGC) unit is built for output amplitude stabilisation. A new transformer design is also proposed. The dimension of the quadrupole being used as a mass filter will be determined in the future. This circuit (in particular the transformer and the quadrupole connection/mounting device) will be finalised after the design of the quadrupole. Finally, this thesis concludes with a discussion between the gain and the noise performance of an FT-ICR preamplifier. A brief analysis about the correlation between the gain, cyclotron frequency, and input capacitance is performed. Future work is also suggested for extending this research.
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Rothe, Eric V. (Eric Vaughn). "Mass." Thesis, North Texas State University, 1985. https://digital.library.unt.edu/ark:/67531/metadc504172/.
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Mass is written for large mixed choruswind ensemble consisting of woodwind quartet (flute, oboe, Bb clarinet, and bassoon), brass quintet (two Bb trumpets, F horn, trombone, bass trombone), and recorded digital synthesizer. This setting of the Ordinary is in Latin and includes the Kyrie, Gloria, Credo, Sanctus, and Agnus Dei. The duration of the work is approximately twenty-seven minutes.
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Gifford, Eric Allan 1965. "Hough transform extraction of cartographic fiducial marks from aerial photography." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277903.
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Cartographic compilation requires precision mensuration. The calibration of mensuration processes is based on specific fiducials. External fiducials, around the exterior frame of the image, must be precisely measured to establish the overall physical geometry. Internal fiducials are provided within the image by placement of cloth panels on the ground at locations whose position is precisely known. Both types of fiducials must be known within the pixel space of a digitized image in order for the feature extraction process to be accurate with respect to delineated features. Precise mensuration of these fiducials requires that a cartographer view the image on a display and use pointing devices, such as a mouse, to pick the exact point. For accurate fiducial location, the required manual operations can be an added time-consuming task in the feature extraction process. Interactive tools which eliminate the precise pointing action for the operator are described in this thesis. The operator is required only to "box-in" the fiducial, using a simple drawing tool, select the fiducial function, and the software of the tool returns the precise location of the fiducial.
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Kaygin, Sel Sultan. "Industrial Design And The Mass Customization Of Electronic Consumer Goods." Phd thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615705/index.pdf.
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Mass customization is promoted in manufacturing industry as a way to satisfy individual customer requirements in a flexible, efficient and cost effective way. However, mass customization within the specific sector of &lsquoelectronic consumer goods&rsquo
is relatively underdeveloped, whilst the contributions of industrial designers to mass customization remain quite unclear. This research redresses both of these issues, elaborating on the possibilities of mass-customization in the electronic consumer goods sector, and explaining how industrial designers can take a central role in implementation. Chapter 2 contains a literature review on key terms related to mass customization. A portfolio of mass customization case studies, from both within and outside electronic consumer goods, are presented and analyzed in Chapter 3, which also reports on a new classification system to define six discrete customization types. User needs research methods, including IDEO methods, are reviewed in Chapter 4 to determine those methods most applicable for use in the pilot (Chapter 5) and main (Chapter 7) &lsquo
research through design&rsquo
customization projects. The pilot project, conducted with METU industrial design undergraduates, explored opportunities and barriers for mass customization of electronic consumer goods
the main project, carried out by the Vestel ID Team under the SAN-TEZ scheme, resulted in a new mass customized all-in-one (AIO) PC for Vestel Electronics. In Chapter 6, results of interviews with Vestel staff are presented, uncovering the current situation within Vestel Electronics for implementing mass customization. Chapter 8 contains the research conclusions, including discussion of a proposed design-based mass customization design and development procedure.
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Yu, Xing 1974. "Comparing electronic commerce solutions for small businesses." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31562.
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E-commerce is a new way of doing business. It is becoming increasingly important to everybody. The objective of this thesis is to compare various design approaches and to find out the best solution for small businesses. Some commonly used technologies in developing e-commerce systems are introduced in the first three chapters. The topics covered are from Web standards and protocols to Web planning and design, from Web servers to server side programming, and most importantly, Java technology and IBM's WebSphere. Based on these technologies, two solutions are presented: building from scratch with Java servlets and building with IBM's WebSphere. We develop an online store with each of the solutions. The last part of the thesis is a comprehensive comparison. Time, complexity, performance and cost are evaluated in this comparison. A simple conclusion is drawn afterwards with our suggestions to small businesses regarding which solution they should choose.
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Delannoy, Jean-Christian. "Modeling articulated bodies with distributed mass for virtual interactive environments." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27238.
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Dynamic simulation is a powerful application of contemporary computers, it has uses that range from design and manufacturing to simulation and entertainment products. This work investigates dynamic simulation of articulated bodies in interactive virtual environments. Previous techniques for both modeling articulated bodies in virtual environments as well as simulating their motion are qualitatively compared for the twin goals of correctness of results and computational efficiency. Implementations of the Verlet system and the method of stiff springs for articulated bodies are quantitatively compared when used for bodies with segments of varied mass in interactive virtual environments. Finally, a novel adaptation of the Verlet technique for simulating constrained and articulated bodies is presented. Through this adaptation to the Verlet algorithm we are able to simulate bodies with links of inconsistent mass more faithfully than with previous implementations.
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Chang, Chung-jen. "Society, state, and electronic media policy : the introduction of cable to Taiwan /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1302628268.
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McMillan, Donald Calum. "Mass participation user trials." Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3656/.
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This thesis investigates how researchers can take advantage of the rapid adoption of mobile technology that has brought with it transformations in social and cultural practice; the expectations of what computers are, what they can do, and the role of digital objects in everyday life. In particular this thesis presents and discuses the use of new App Store style software distribution methods to reduce the cost, in terms of researcher time and hardware, of recruiting a large group of participants for a trial ‘in the wild’ while increasing the potential diversity of users is becoming an attractive option for researchers pursuing the ubicomp vision. It examines the procedures for running large scale trials with the deployment of three applications released to a combined user base of over 135,000 in such a way as to keep the qualitative detail necessary to inform design while gain- ing the diversity of users for claims of generalisability. More generally, it discusses the results that can be expected from this ‘mass participation’ approach, and the ethical responsibilities they place upon researchers. The contributions of this thesis for mobile HCI show that in large-scale trials, relatively rich qualitative data can be collected along with substantial quantitative data, and that a hybrid trial methodology combining a large- scale deployment with a local trial can be a powerful tool in addressing shortcomings of trials that are either solely local or solely global. This thesis also contributes guidelines for researchers running large-scale user trials that give consideration to the established research norms and practices, in an attempt to strike a new balance between invasiveness and utility.
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Pendse, Nachiket C. "Crash safety assessment of bus operators in mass transit buses." Thesis, Wichita State University, 2007. http://hdl.handle.net/10057/1545.
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Mass transportation systems and specifically bus systems are a key element of the national transportation network. According to the Traffic Safety Facts report from 1999-2001, total of 333 fatal involvements of transit bus operators in fatal crashes have been reported from 284,000 bus related traffic accidents. Thus bus occupant safety research is an effort for the enhancement of bus operator safety. Crashes resulting in injuries were distributed between front, door side, driver side and rear collisions. This study is aimed at the evaluation of potential bus operator injuries during different accident scenarios of a mass transit bus in frontal, side and rear crashes. Dynamic sled tests of the bus operator and its environment are first conducted at National Institute for Aviation Research. From Numerical models of the crash event including bus and bus operator are developed using the MADYMO and LSDYNA codes, and validated against the experimental sled tests. Validation is carried out by comparing the kinematics of the bus operator represented by a Hybrid III ATD in actual sled tests and simulations. To ensure validity, a comparison of various acceleration profiles and forces -moments experienced by the bus operator under various test conditions are compared. Furthermore, potential injury levels sustained by the operator in the actual sled tests and the simulations are compared with FMVSS standards. This is done to analyze biomechanical performance under different loading conditions. The developed models once validated for their realistic applications, are performed with parametric study to obtain optimized configuration that provides protection to bus operator in the course of a crash.Thesis (M.S)-- Wichita State University, College of Engineering, Dept. of Mechanical Engineering
"December 2007."
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Pendse, Nachiket C. Lankarani Hamid M. "Crash safety assessment of bus operators in mass transit buses /." Thesis, A link to full text of this thesis in SOAR, 2007. http://hdl.handle.net/10057/1545.
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Tellez, Galdino Mejia. "Infrared characterization of SiN films on Si for high speed electronics applications." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FTellez.pdf.
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Thesis (M.S. in Applied Physics)--Naval Postgraduate School, December 2004.Thesis advisor(s): Gamani Karunasiri, Ronald E. Brown. Includes bibliographical references (p. 33). Also available online.
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Thokade, Sujeet S. "Passenger safety in real-life crash scenarios of mass transit buses." Thesis, Wichita State University, 2007. http://hdl.handle.net/10057/1556.
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Buses and coaches form a vital part of the national as well as city public transportation network. Buses are still one of the safest modes of transportation. Nevertheless, bus accidents resulting in passenger injuries and fatalities do occur. According to the Traffic Safety Facts statistical reports from 1999 to 2003, an average of 40 fatalities and 18,430 injuries of bus occupants occurred per year. These accidents involved normal vehicle impacts, such as head-on or rear-end collisions. In this thesis the crashworthiness of the passenger compartment in a mass transit bus is evaluated and interior design guidelines that will mitigate the fatalities and injuries of the occupants during a crash event are recommended. Computational modeling and crash sled testing are used to analyze the frontal, side and rear accident scenarios in the passenger compartment. This report includes the evaluation of occupant injury during three accident scenarios by validating numerical models through MADYMO and LSDYNA codes versus experimental sled tests using Federal Motor Vehicle Safety Standards (FMVSSs) 208 injury criteria. Interior components are evaluated against crashworthiness requirements from the FMVSS and the Standard Bus Procurement Guidelines (SBPG). The sled pulses were generated from validated bus model finite element (FE) simulations of critical real-crash scenarios for frontal, rear and side conditions. The validated numerical model was then subjected to parametric studies to analyze the influence of the current vehicle interior design parameters, e.g., Seat spacing, seat height, location etc. on passenger kinematics and biomechanical performance. This study was carried out through a Design of Experiments (DOE). Optimization studies were carried out to define new bus interior designs that would reduce or mitigate passenger injuries.Thesis (M.S)-- Wichita State University, College of Engineering, Dept. of Mechanical Engineering
"December 2007."
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Thokade, Sujeet S. Lankarani Hamid M. "Passenger safety in real-life crash scenarios of mass transit buses /." Thesis, A link to full text of this thesis in SOAR, 2007. http://hdl.handle.net/10057/1556.
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Giannoukos, Stamatios. "Portable mass spectrometry for artificial sniffing." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2013500/.
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On-site chemical detection and monitoring of compounds related to homeland security applications, civil defence and forensics is difficult using conventional instrumentation. Target analytes include human chemical signatures (for detection of illegal immigration), drugs of abuse, explosives and chemical warfare agents (CWAs). A convenient solution is to complement existing techniques using portable membrane inlet mass spectrometry (MIMS). This thesis deals with the mass spectrometric investigation of characteristic chemical odour signatures emitted by human exhaled breath and skin as chemical signs of human presence in a confined space. It also presents detection results of threat and threat related chemical compounds. Numerical modelling of ion injection and confinement in a non-scanning linear ion trap (LIT) mass analyser for achieving sensitivity enhancement was carried out. A novel portable artificial sniffer based on linear ion trap (LIT) technology has been designed and developed. Initial performance results are described. Preliminary field trials have led to positive outcomes which are currently being commercially exploited.
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Balwan, Nishant Kuber. "Implementation and evaluation of automotive child restraint systems in mass transit buses." Thesis, Wichita State University, 2008. http://hdl.handle.net/10057/2083.
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Mass transportation systems and specifically bus systems are a key element of the national transportation network. Buses are one of the safest forms of transportation. Nonetheless, bus crashes resulting in occupant injuries and fatalities do occur. Each year, more than 5,800 children die, nearly 120,000 are permanently disabled, and more than 14 million are hurt seriously enough to require emergency medical care due to unintentional injury. Therefore, effort is needed to improve the performance of bus interior and structure. Child Safety is a continuing effort to improve the safety of children in mass transit buses. This project provides an overview of the implementation of two types of attachment systems Child Restraint Systems (CRS) in a mass transit buses. A series of sled tests were conducted in order to evaluate the performance of the Child Restraint Systems for typical frontal, side and rear crash scenarios. The results of the test indicate that the implementation of ISOFIX or LATCH attachments in transit bus seats mitigates the risk of severe injuries to the 12 month-old, and 3 year-old occupants; while not increasing the risk of severe injuries due to CRS interactions to other unrestraint adult passengers. In the next phase of this research, results from these sled tests were validated using the multibody analysis tool MADYMO to evaluate the performance of child safety in mass transit buses using the Federal Motor Vehicle Safety Standards (FMVSS 208) injury criteria. The Kinematics of sled tests are closely matching with that of simulations. Injury values for sled tests and simulations are well below injury criteria. The results from this study show the 20 % variation in injury signals. This study concludes that interior for mass transit bus with child seats and restraint can be utilized in mass transit buses to improve the safety performance of children.Wichita State University, College of Engineering, Dept. of Mechanical Engineering
Includes bibliographic references (leaves 83-86)
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Balwan, Nishant Kuber Lankarani Hamid M. "Implementation and evaluation of automotive child restraint systems in mass transit buses." A link to full text of this thesis in SOAR, 2008. http://hdl.handle.net/10057/2083.
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Syed, Sarfaraz Uddin. "Quadrupole mass spectrometry under the influence of magnetic field." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/5533/.
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A Quadrupole Mass Spectrometer (QMS) is an instrument for measuring concentrations of atoms and molecules by separating atomic and molecular ions according to their mass-to-charge ratios (m/z). It consists primarily of an ion source, quadrupole mass filter (QMF) and detector. Generally, QMF resolution can be improved by increasing the number of rf cycles of the alternating electric field the ion experiences when passing through the mass filter. In order to improve the resolution, the dimensions of the QMF or the operating parameters are to be changed. However geometric modifications to improve performance increase the manufacturing cost and usually the size of the instrument. A low cost method to increase the resolution of a given QMS is the application of magnetic field to the mass filter. The work is mainly concerned with the performance of a QMS under the influence of magnetic field. Significant improvement in QMS performance was obtained under certain magnetic field conditions, and these have been explained in terms of our theoretical model developed in the University of Liverpool. The theoretical approach assumed in the model is that the QMF contains hyperbolic rods as electrodes and that the magnetic field acts over the full length of the mass filter assembly. This model is capable of accurate simulation of spectra allowing the user to specify different values of mass spectrometer dimensions and applied input signals. The model has been upgraded for better sensitivity, and to simulate the QMF at very high number of rf cycles. Simulation and experimental results were presented for different conditions. This work also demonstrates the modeling of mass spectra of gases using the theoretical model for stability zones 1 and 3. The performance of QMF operating in stability zones 1 and 3 has been derived and a relationship between maximum obtainable resolution and scan line is obtained.
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Palmer, Andrew D. "Information processing for mass spectrometry imaging." Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/5472/.
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Mass Spectrometry Imaging (MSI) is a sensitive analytical tool for detecting and spatially localising thousands of ions generated across intact tissue samples. The datasets produced by MSI are large both in the number of measurements collected and the total data volume, which effectively prohibits manual analysis and interpretation. However, these datasets can provide insights into tissue composition and variation, and can help identify markers of health and disease, so the development of computational methods are required to aid their interpretation. To address the challenges of high dimensional data, randomised methods were explored for making data analysis tractable and were found to provide a powerful set of tools for applying automated analysis to MSI datasets. Random projections provided over 90% dimensionality reduction of MALDI MSI datasets, making them amenable to visualisation by image segmentation. Randomised basis construction was investigated for dimensionality reduction and data compression. Automated data analysis was developed that could be applied data compressed to 1% of its original size, including segmentation and factorisation, providing a direct route to the analysis and interpretation of MSI datasets. Evaluation of these methods alongside established dimensionality reduction pipelines on simulated and real-world datasets showed they could reproducibly extract the chemo-spatial patterns present.
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Kim, Younglae. "Imagination and religious education in the electronic media age." Theological Research Exchange Network (TREN), 1992. http://www.tren.com.
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Tabbara, Tarik. "Electronic mass media and freedom of expression in Germany, the United States and Canada." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27467.
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This thesis examines the constitutional guarantee of freedom of expression as applied to electronic mass media. It compares the different approaches adopted in Germany, the United States and Canada. After an overview of freedom of expression doctrine in general and the main features of the regulation of electronic mass media the rationalization of this regulation in freedom of expression doctrine is analyzed.The focus of this analysis is how electronic mass media have changed the traditional understanding of fundamental rights and freedoms as purely negative individual guarantees. This change occasions and necessitates a closer look at governmental regulation and the role of the state, and the different conceptions of freedom of expression that can be used to justify it.
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Huang, Ziyi. "Rating methodology of high voltage mass impregnated DC cable circuits." Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/372744/.
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With the continuing growth in energy consumption worldwide, the move towards a European wide super grid will result in significant changes in how modern transmission and distribution networks are operated. Fundamental to this is the need to accurately know or determine the available ampacity of high voltage cable circuits, because huge bulk power volumes need to be transmitted between maritime nations through dc power cables. Therefore, an accurate cable rating becomes paramount towards an efficient and safe operation of transmission networks, while the finance for large scale network construction schemes is limited. Although the standardised thermal-limited rating has been successfully implemented for traditional ac cable networks for over 50 years, the move towards dc cable transmission imposes extra physical constraints on the cable rating, which are not considered by standard rating approaches. The two main concerns are the potential dielectric electrical breakdown prior to a normal thermal runaway and the development of dielectric cavities during cable cooling. In addition, the thermal-limited rating of submarine dc cable crossings, within a complex marine environment, requires an advanced numerical modelling method, where the traditional IEC thermal-limited rating method does not apply. Besides the technical value, significant interest exists both within the electrical power industry and organizations such as Cigré and IEC, because this work will inform future international standards for rating high voltage dc cables. Considering the dielectric electrical stress constraint as the limiting factor for cable ratings, an analytical electrical stress-limited rating method has been developed and successfully benchmarked by numerical simulations for a practical cable design. This method allows ratings to be calculated against a criterion of maximum dielectric electrical strength. Considering the dielectric cavity creation threshold as the limiting factor for cable ratings, a comprehensive study has been conducted, including thermal dynamics, theory of elasticity and electrical circuit theory. Subsequently, the analytical calculation of the cable internal pressure has been originally developed, together with a concept of the mechanical pressure-limited rating. The method has been successfully demonstrated for a practical cable design, yielding a rating which prevents the creation of cavity due to potential plastic deformations of the cable sheath. When crossings are inevitably installed, cables are pushed towards their thermal limit, as a result of the mutual heating. In order to accurately rate these circuits under various ambient conditions; Finite Element Analysis (FEA) methods have been developed. Compared to the traditional IEC calculation, FEA modelling provides a more reasonable and accurate solution, by releasing idealistic assumptions in the IEC method. In addition, a systematic cable rating strategy has been suggested and successfully demonstrated through rating submarine high voltage dc cable crossings, which considers highly coupled physics: thermal, electrical and mechanical. In summary, this thesis contributes towards the modern rating methodology development for hvdc mass impregnated cable circuits, under a purpose of efficient and reliable long-term operation.
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Zhang, Kewen. "The computer network-based media and ethnic electronic community /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9904877.
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Boiani, Filippo. "Blockchain Based Electronic Health Record Management For Mass Crisis Scenarios : A Feasibility Study." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254875.
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Electronic Health Records (EHRs) are both crucial and sensitive as they contain essential information and are frequently shared among different parties including hospitals, pharmacies or private clinics. This information must remain correct, up to date, private, and accessible only to the authorized people. Moreover, the access must also be assured under special conditions mass crises like hurricanes or earthquakes where disruption, decentralized responses, and chaos could potentially lead to wrong procedures or even malicious behaviors. The introduction of blockchain a distributed ledger where the records are stored in a linked sequence of blocks and are theoretically difficult to delete or tamper with made possible to design and implement new solutions for more failure-resistant EHRs applications adopting a distributed and decentralized philosophy, in contrast with the central ones based on cloud infrastructures or even local solutions. In this context, this work provides a systematic study to understand whether permissioned blockchain implementations could be of any benefit to managing health records in emergency situations caused by natural disasters. After the design and implementation of a basic prototype for an EHRs management system in Hyperledger Fabric and the execution of a set of test cases based on the simulation of the Haiti earthquake of 2010, it was possible to discuss the benefits and tradeoffs that the system entails. The discussion focused on the performance parameters like throughput, latency, memory and CPU usage. The system allowed the patients and practitioners to share and access EHRs and be able to detect and react to the crisis situations. Moreover, it behaved correctly in the presence of malicious nodes assuring throughputs and latencies still lower, compared to current centralized systems like credit card payments, but already up to two orders of magnitude higher than permissionless blockchain implementations. Even though there is still a lot of work to do, the system represented by the prototype could be an interesting alternative for networks of healthcare companies to help ensuring the continuity of treatment while preserving privacy and confidentiality in extreme situations.Electronic Health Records (EHRs) är både viktiga och känsliga då de innehåller viktig information som ofta delas mellan flera parter, såsom sjukhus, apotek, och privata kliniker. Den här informationen måste hållas korrekt, uppdaterad, privat, och tillgänglig endast till auktoriserad personer. Vidare, tillgången till information måste vara försäkrad under extraordinära händelser, masskriser såsom orkaner och jordbävningar då distribution, decentraliserade åtgärder, och kaos potentiellt kan leda till fel åtgärder, till och med skadligt beteende. Introduceringen av blockchain en distruberad ledger"vars recordslagras i en länkad sekvens av block som är teoretiskt svåra att förstöra eller manipulera har möjligjort designen och implementationen av ny lösningar för mer krashresistanta EHR applikationer som antar en distribuerad och decentraliserad filosofi, i motsats till de centrala som bygger på molninfrastrukturer eller till och med lokala lösningar. I det här sammanhanget ger detta arbete en systematisk studie för att förstå huruvida permission-baserade blockchain-implementationer kan vara till nytta för att hantera hälso information (records) i nödsituationer orsakade av naturkatastrofer. Efter utformningen och genomförandet av en grundläggande prototyp för ett system för hantering av EHR i Hyperledger Fabric och genomförandet av en uppsättning testfall baserade på simuleringen av jordbävningen i Haiti 2010 kunde vi diskutera de fördelar och avvägningar som systemet medför. Diskussionen fokuserade på prestanda parametrar som throughput, latens, minne och CPU-användning. Systemet gjorde det möjligt för patienterna och utövarna att dela och komma åt EHR och kunna upptäcka och reagera på krissituationerna. Dessutom uppträdde det korrekt i närvaro av skadliga noder och säkerställde throughput och latens, vilket var lägre jämfört med nuvarande centraliserade system som kreditkortsbetalningar, men upp till två storleksordningar högre än permission-lösa blockchain-implementeringar. Trots att det fortfarande finns mycket arbete att göra skulle det system som representeras av prototypen kunna vara ett intressant alternativ för nätverk av sjukvårdsföretag, för att hjälpa till i extrema situationer och garantera kontinuiteten i behandlingen, samtidigt som sekretess och konfidentialitet bevaras.
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Wandy, Joe. "Unsupervised Bayesian explorations of mass spectrometry data." Thesis, University of Glasgow, 2017. http://theses.gla.ac.uk/7928/.
Full textAbstract:
In recent years, the large-scale, untargeted studies of the compounds that serve as workers in the cell (proteins) and the small molecules involved in essential life-sustaining chemical processes (metabolites) have provided insights into a wide array of fields, such as medical diagnostics, drug discovery, personalised medicine and many others. Measurements in such studies are routinely performed using liquid chromatography mass spectrometry (LC-MS) instruments. From these measurements, we obtain a set of peaks having mass-to-charge, retention time (RT) and intensity values. Before further analysis is possible, the raw LC-MS data has to be processed in a data pre-preprocessing pipeline. In the alignment step of the pipeline, peaks from multiple LC-MS measurements have to be matched. In the identification step, the identity of unknown compounds in the sample that generate the observed peaks have to be assigned. Using tandem mass spectrometry, fragmentation peaks characteristic to a compound can be obtained and used to help establish the identity of the compound. Alignment and identification are challenging because the true identities of the entire set of compounds in the sample are unknown, and a single compound can produce many observed peaks, each with a potential drift in its retention time value. These observed peaks are not independent as they can be explained as being generated by the same compound. The aim of this thesis is to introduce methods to group these related peaks and to use these groupings to improve alignment and assist in identification during data pre-processing. Firstly, we introduce a generative model to group related peaks by their retention time. This information is used to influence direct-matching alignment, bringing related peak groups closer during matching. Investigations using benchmark datasets reveal that improved alignment performance is obtained from this approach. Next, we also consider mass information in the grouping process, resulting in PrecursorCluster, a model that performs the grouping of related peaks in metabolomics by their explainable mass relationships, RT and intensity values. Through a second-stage process that matches these related peak groups, peak alignment is produced. Experiments on benchmark datasets show that an improved alignment performance is obtained, while uncertainties in matched peaksets can also be extracted from the method. In the next section, we expand upon this two-stage method and introduce HDPAlign, a model that performs the clustering of related peaks within and across multiple LC-MS runs at once. This allows for matched peaksets and their respective uncertainties to be naturally extracted from the model. Finally, we look at fragmentation peaks used for identification and introduce MS2LDA, a topic model to group related fragmentation features. These groups of related fragmentation features potentially correspond to substructures shared by metabolites and can be used to assist data interpretation during identification. This final section corresponds to a work in progress and points to many interesting avenues for future research.
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Enweluzor, M. P. C. "Instrument for solids mass flow measurement in pneumatic conveyors." Thesis, University of Bradford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373225.
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Moon, Sanghyun. "CONSTRUCTING GOVERNANCE IN GLOBAL ELECTRONIC COMMERCE." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1038941025.
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Saunders, Ryan C. "Beyond media literacy in the language arts classroom [electronic resource] /." Online pdf file accessible through the World Wide Web, 2010. http://archives.evergreen.edu/masterstheses/Accession89-10MIT/Saunders_RCMIT2010.pdf.
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Oostendorp, Marcelyn Camereldia Antonette. "Investigating changing notions of "text": comparing news text in printed and electronic media." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_9984_1183428106.
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This research aimed to give an account of the development of concepts of text and discourse and the various approaches to analysis of texts and discourses, as this is reflected in core linguistic literature since the late 1960s. The idea was to focus specifically on literature that notes the development stimulated by a proliferation of electronic media. Secondly, this research aimed to describe the nature of electronic news texts found on the internet in comparison to an equivalent printed version, namely texts printed in newspapers and simultaneously on the newspaper website.
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Jadhav, Yuvraj S. "Crashworthiness of wheel-chaired occupants with restraint system for real-life crash scenarios of mass transit buses." Thesis, Wichita State University, 2007. http://hdl.handle.net/10057/1539.
Full textAbstract:
The aim of this research was to study the behavior of a wheel-chaired occupant for different crash scenarios in a mass transit bus. Actual crash sled tests were carried out at the National Institute for Aviation Research (NIAR) crash laboratory facility and validated according kinematics and injury parameters. Setup of these crash tests was done by following various wheelchair restraint and tie-down standards. Other factors, such as wheelchair placement in a bus environment were taken into consideration while preparing the sled tests. The Hybrid III 50th percentile anthropometric test device (ATD) was used for all crash pulses, as it represents the weight and size of an average American. A detailed Computer-Aided design (CAD) model using CATIA V5 was created by applying a reverse engineering technique. This CAD model was then used to prepare a detailed finite element model (FEM) and a facet model which were used for carrying out simulations with the help of software such as MADYMO for multi-body dynamics and LS-DYNA for finite element analysis. These two models were then simulated for the same crash pulses as the actual sled tests to study the kinematics and injury parameters. To define correct material properties tension tests of the belt material were carried out to obtain the actual belt webbing characteristics. The detailed finite element model was developed and used to study the exact force-displacement relationship and to obtain the proper kinematics. Simulations were run using both software for all crash tests, and the kinematics and injury values were validated with the actual crash test values and kinematics. Validation was done using the Motion View software. The validation of the tests was studied to discern the various parameters responsible for the injury values of the wheel-chaired occupant. Further, a more detailed parametric study was carried out where these parameters were changed or modified to create combinations of restraint and securement systems, in order to provide an overview of the appropriate choice of restraint and securement system to reduce the potential injury to the wheel-chaired occupant.Thesis (M.S)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering
"December 2007."
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Jadhav, Yuvraj S. Lankarani Hamid M. "Crashworthiness of wheel-chaired occupants with restraint system for real-life crash scenarios of mass transit buses /." Thesis, A link to full text of this thesis in SOAR, 2007. http://hdl.handle.net/10057/1539.
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Sawyer, Frederick Emile. "Coupled mixing-cell and mass balance flow path models of the White River Flow System, Nevada, USA." abstract and full text PDF (UNR users only), 2009. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1467765.
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Tabbara, Tarik. "Electronic mass media and freedom of expression in Germany, the United States and Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ29842.pdf.
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Chunara, Rumi. "Electronic readout of microchannel resonators for precision mass sensing in solution by Rumi Chunara." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/57803.
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Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 115-120).
Microfabricated transducers have enabled new approaches for detection of biomolecules and cells. Integration of electronics with these tools simplify systems and provide platforms for robust use outside of the laboratory setting. Suspended microchannel resonators (SMRs) are sensitive microfluidic platforms used to precisely measure the buoyant mass of single cells and monolayers of protein in fluid environments. Conventionally, micro cantilever deflection is measured by the optical-lever technique, wherein a laser beam is reflected off the cantilever onto a position sensitive photodiode. This thesis introduces microchannel resonators with electronic readout, eliminating the use of external optical components for resolving the sensor's resonant frequency. Piezo resistors have been fabricated on SMRs through ion implantation integrated with the existing SMR fabrication process. We fabricated two designs: one with a cantilever length of 210 pm and resonant frequency of -347 kHz, and the other with a cantilever length of 406 pm and resonant frequency of ~92 kHz. The work here builds upon knowledge of signal transduction from static and dynamic cantilever based sensors because the piezo resistors are implemented on vacuum encapsulated devices containing fluid. Electronic readout is shown to resolve the microchannel resonance frequency with an Allan variance of 5 x 10-18 (210 pm) and 2 x 1017 (406 pm) using a 100ms gate time, corresponding to a mass resolution of 0.1 and 0.4 fg respectively. This mass resolution calculated from piezoresistive readout frequency stability, is approximately 3X better than optical readout for the 210 pm device and 1.3X for the 406 pm device using the same gate time. Resolution is expected to improve with further optimization of the system. To demonstrate the readout, histograms of the buoyant masses of a mixture of size standard polystyrene beads (with nominal diameters 1.6, 1.8, and 2.0 pm) and budding yeast cells were made.
Ph.D.
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Hull, Alexander W. (Alexander William). "Collisional transfer between excited electronic states as a mechanism for sulfur mass-independent fractionation." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/130591.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, September, 2020Cataloged from the official PDF of thesis. Page 242 blank.
Includes bibliographical references (pages 235-241).
The Great Oxygenation Event, the introduction of O2 into the Earth's atmosphere approximately 2.5 billion years ago, is a critical milestone in the development of life on Earth. The exact timing of this event is thought to be correlated with the disappearance of Archean sulfur isotopic anomalies, called Sulfur Mass -Independent Fractionation (S-MIF), in the rock record. This anomalous fractionation pattern can be described, generally, as an enrichment in the three rare isotopes: S-33 (0.75%), S-34 (4.25%) S-36 (0.01%), relative to the most abundant isotopologue S-32 (0.75%), However, the mechanism for the generation of S-MIF in a reducing atmosphere is still unknown. I use the B-X UV transition (~31,000-36,000 cm⁻¹) in S₂ as a proxy for study of excited state collisional transfer as a possible mechanism for S-MIF. The short-lifetime B state (natural lifetime: 32 ns) state-mixes extensively with a longer-lifetime B" state (4200 ns).
Furthermore, the most abundant isotopologue of S₂, ³²S-³²S has only half the number of rotational states compared to its asymmetric counterparts. In this work, I replicated Green and Western's effective Hamiltonian for the X, B, and B" states with additional considerations for mass-dependent vibrational level shifts and nuclear permutation effects. I hypothesize that the collisional transfer between the B and B" states occurs differently for different isotopologues. This difference results in a different average excited state lifetimes, which, in turn, affects the relative rate at which they undergo chemical reactions and enter the rock record. Here, spectroscopic B/B" perturbations act as doorways through which population can exchange between the B and B" states. My model incorporates absorption, fluorescence, and predissociation, as described by Green and Western.
It also includes the Gelbart-Freed model for electronically inelastic collisions and Brunner and Pritchard model for rotationally inelastic collisions. I calculate the amount of each isotopologue that enters the rock record by time-dependently solving a master equation kinetic model. Results show that, generally, each region where a B vibronic state crosses a B" vibronic state behaves differently. However, the interactions display some systematic behavior. Because of the energy level patterns, lighter isotopologues are generally favored over the heavier ones (i.e. 32-36 < 32-34 < 32-33 < 32-32) in the absence of predissociation. When predissociation is present the trend reverses, but remains Mass-Dependent, and cannot explain the S-MIF signature in the rock record. The most important conclusion, however: the interactions with the smaller B/B" state-mixing showed the larger isotope effects.
To continue my analysis, therefore, I considered the same B/B" system where the perturbation matrix elements are 1% of their original Green and Western values, i.e. a "weak perturbation model". Here, I develop a statistical doorway model, which posits that doorway locations are somewhat random, and that the asymmetric isotopologues converge to a limiting, ensemble behavior at lower pressures than do symmetric species that are missing half of their rotational states. Results show that this statistical isotope effect is relevant to the weak perturbation model, and may help explain the anomalous isotope patterns in the rock record. Further analysis shows that non-statistical effects may also play a critical role. These include transfer between B and B" states with very small state-mixing (as little as 0.005% ) and non-statistical doorway sampling. I conclude that a model that combines statistical and non-statistical isotope effects may explain Archean S-MIF.
by Alexander W. Hull.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Chemistry
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Chien, Wen-Fang Winnie. "Investigation of uranium and various ligand complexes in the gas phase using electrospray ionization ion trap mass spectrometry." Thesis, Wichita State University, 2007. http://hdl.handle.net/10057/1518.
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The speciation and reactivity of uranium is a topic of sustained interest because species dependent chemistry controls processes ranging from nuclear fuel processing to mobility and fate in the geological surface. Past condensed phase studies have shown uranium a wide range of oxidation states and coordinate ion numbers in the environment. These studies have also suggested the strong interactions such as charge transfer between the uranium cations and solvent molecules cause the latter to behave like equatorial ligands. Studying and understanding intrinsic uranium chemistry is challenging because it is difficult to gain explicit control over the interactions of solvent and non-solvent ligands with uranyl ions in the condensed phase. An attractive alternative, therefore, is to monitor reaction in the gas phase (i.e. a solution free environment) in order to gain control over the chemical species chosen for study and the specific neutral reagents. Recent studies shown that ion-trap mass spectrometry can be applied to the study of intrinsic metal and metal-complex chemistry by generating the metal complexes as ions through electrospray ionization ESI and allowing species to interact with neutral reagents present in the collision gas. Throughout these series of uranyl studies, ESI is used to produce gas-phase ions from solutions containing uranyl nitrate complexes in deionized water. Several studies were conducted to monitor uranium and ligands behavior under different systems by controlling factors such as the numbers of ligands attached to the uranium dioxo cation center, ligand degrees of freedom, and ligand basicities. These studies were designed to gain clear insight to the intrinsic behavior of uranium complexes.Thesis (M.S.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry
"December 2007."
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Chien, Wen-Fang Winnie Van Stipdonk Michael J. "Investigation of uranium and various ligand complexes in the gas phase using electrospray ionization ion trap mass spectrometry /." Thesis, A link to full text of this thesis in SOAR, 2007. http://hdl.handle.net/10057/1518.
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Wang, Yifan 1963. "Audiovideo services for a virtual laboratory." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26438.
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This thesis presents the design and implementation of a framework for audio/video services for a virtual laboratory. A library of subroutines was developed to support a network video/audio server, capable of performing multimedia interactive presentations in this networked environment. The network video/audio server is an upgraded form of ACME.In a virtual laboratory, the server's file system can be used to store laboratory lessons, combining circuit simulations such as SPICE or mathematical computations using MATLAB with sounds and video sequences. The clients are able to access the server's file system via TCP/IP connections and to playback a sound or a video sequence, to record a voice message, and to send a voice message or a video sequence to another workstation. The server's workstation and the client's workstations are able to perform real time audio voice communication between each other via the video/audio server. The clients can also send voice commands from the local workstation to the voice recognition toolkit in the server workstation via a TCP/IP connection with the audio/video server for hands-free interactive presentations.
The experimental results indicate that the audio/video performance is suitable for multimedia presentations in a virtual laboratory environment. The suggestions for the future development of the virtual laboratory design are presented.
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ALshammari, Musaed. "How Kuwaiti College Students in the United States Use and Perceive Electronic News Media| A Case Study." Thesis, Arkansas State University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10977267.
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The purpose of this study was to formulate a preliminary conceptual perception about how Kuwaiti college students in the United States use and perceive electronic media. This qualitative study has sought to recognize the utilization habits and perception of Kuwaiti college students in the USA toward electronic media. The study examines the reasons for the high degree of dependency on electronic media by Kuwaiti students in the USA and the most significant features and properties that are available by electronic media, which attract youth attention. This research conducted semi-structured, in-depth interviews with a sample of 15 Kuwaiti college students in the United States. It was concluded that Kuwaiti college students are the major users of recent technology and pioneers of electronic and social media. It also seeks for future investigations to understand whether the demographic characteristics of Kuwaiti college students are affecting their media utilization habits.
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Cridland, April Louise. "Development of a planar penning trap for quantum applications with electrons." Thesis, University of Sussex, 2018. http://sro.sussex.ac.uk/id/eprint/80554/.
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This thesis presents the development of the Geonium Chip, a planar Penning trap. The Geonium Chip consists of the five electrodes of a cylindrical Penning trap projected onto the surface of a microfabricated chip. Beneath the chip is a planar magnetic field source currently made from coils of niobium titanium wire. Traditionally the magnetic field source is a large superconducting solenoid, replacing this with a planar source makes the setup scalable, portable and economical. The Geonium Chip, with its magnetic field source and detection electronics, need to be placed in a cryostat. In this thesis, I describe the development of the cryogenic setup with particular emphasis on the design and optimisation of the non-destructive detection system. I detail the cryogenic wiring of the cryostat including the thermalisation of high current wires and the noise reduction techniques employed on the detection signal. In addition, I explore the parasitic capacitances of the Geonium Chip using microwave network analysis and describe the testing of the magnetic field source at 4 K. Finally, I discuss the generation of electrons within the trap and the results of our first attempts at trapping a cloud of electrons. Together, the chip and the magnetic field source can be used to trap ions for ultraaccurate mass spectrometry or an electron for single microwave photon detection. A single microwave photon detector is a tool that is currently still missing in quantum technology and is needed for determining the quantum state of microwave radiation fields. This is vital for quantum communication and cryptography. Additionally, using the Geonium Chip as a mass spectrometer has the potential to lead to very accurate mass spectrums without the need for frequent calibration. Finally, eliminating the expensive superconducting solenoid will make accurate mass spectrometry available to a wider market.