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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Development of a Nanometric Machining Center for Ultraprecision Manufacturing

Cox, Daniel 18 January 2005 (has links)
The demand for reduced-size components and devices is pervasive throughout industrial and commerical sectors. This drive to reduce the achievable size of parts and features has furthered the developmen of processes and tools capable of micro scale fabrication. In particular, one of the directions this field has taken is in scaling down traditional machine tools. Being a relatively young area of manufacturing, the area of miniaturized machining is still developing and a significant portion of work remains yet to be done. As a thorough understanding of this area is still developing, experimental tests play a significant role furthering this process. Therefore the direction of this project has been to explore this field using a predominantly experimental approach. The aim of it being to realize a miniaturized machine tool capable of fabricating features and even parts on the micro scale. Additionally the machine should be controlled as a standard milling machine and also be capable of generating free form three dimensional parts. In parallel to developing a machine tool, the project has also been directed at examining the machine's capabilities through a range of tests. For creating such a machine tool, the process was carried out in a two stages. Each stage involved a miniaturized machine tool at a different level. The first machine tool produced primarily served as a proof of concept structure. By performing a range of tests on this machine, it allowed for useful insights be to gained for developing the subsequent stage along with establishing some base performance characteristics which were also used for subsequent comparisons. The primary contributions made in this research include: the development of a miniaturized machine, the completion of experiments that map out the machine's capabilities, and theoretical calculations which further define these limits.
2

RAPID MICROIMMUNOASSAY WITH ELECTROCHEMICAL DETECTION

Wijayawardhana, Charles Ajith 11 October 2001 (has links)
No description available.
3

Wireless Sensor System for Airborne Applications

Berdugo, Albert, Grossman, Hy, Schofield, Nicole, Musteric, Steven 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / Adding an instrumentation / telemetry system to a test vehicle has historically required an intrusive installation for wiring and powering all elements of the system from the sensor to the telemetry transmitter. In some applications there is need for a flexible and modular instrumentation and telemetry system that can be installed with minimal intrusiveness on an aircraft without the need for permanent modifications. Such an application may benefit from the use of a miniaturized, inexpensive network of wireless sensors. This network will communicate its data to a central unit installed within the aircraft. This paper describes recent efforts associated with the Advanced Subminiature Telemetry System (ASMT) Initial Test Capability Project. It discusses the challenges in developing a wireless sensor network system for use in an airborne environment. These include selection of frequencies, COTS wireless devices, batteries, system synchronization, data bandwidth calculations, and mechanical structure for external installation. The paper will also describe the wireless network architecture as well as the architecture of the wireless sensor and the central control unit.
4

A PCMCIA BASED TELEMETRY AND ACQUISITION SYSTEM

Gross, Jeffrey, Keller, G. E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In this paper, the Miniature Data Acquisition Transceiver System (Mini-DAT), a Type II PC-Card based data acquisition and transceiver system is described. The Mini-DAT was developed by ViaSat and is currently in use at the Air Force Research Lab (AFRL) at Eglin AFB. AFRL is investigating the use of this Industrial, Scientific and Medical (ISM) band system for data collection with advanced munitions. The Mini-DAT combines the advantages of PC-Card technology with an off the shelf interfacing and packaging approach to provide a large array of capabilities in a very small package. The system provides everything needed to collect analog, discrete and digital data, process the data and transfer the data in a wireless fashion using the latest license free spread spectrum modulation technology. The advanced design of the Mini-DAT allows for operation in harsh remote environments, collecting data unattended and accessed remotely. A graphical user interface (GUI) is provided via a Windows 3.x and 95 software package that can be easily customized for specific applications. The Mini-DAT provides fast and reliable error-free data transfer over the 2.4GHz ISM communication band. It operates over a shared 80MHz bandwidth, allowing multiple access of a number of portable units operating simultaneously in the same band.
5

Design and Characterization of a Miniaturized Spectrometer for Wearable Applications

Westover, Tyler Richard 09 August 2022 (has links)
As individual health monitors continue to become more widely adopted in helping individuals make informed decisions, new technologies need to be developed to obtain more biometric data. Spectroscopy is a well-known tool to gain biological information. Traditionally spectrometers are large and expensive making personal or wearable health monitors difficult. Here we present the development and characterization of a miniaturized short wavelength infrared spectrometer for wearable applications. We present a carbon nanotube parallel hole collimator can effectively select a narrow set of allowed angles of light to be separated by a linear variable filter and detected at a photodiode array making a spectrometer. We will go over the calibration of the spectrometer showing a resolution of 13 nm at 1300 nm. Improvements on the original collimator data will be discussed, including carbon nanotube growth without infiltration and growth on transparent substrates. We will also show measurements made on human subjects yielding a pulse.
6

Design of a Miniaturized X-band Chebyshev Band-pass Filter Based on BST Thin Film

Zhang, Chenhao 21 August 2012 (has links)
No description available.
7

Design and Characterization of a Miniaturized Fluorescence Analysis System for Measurement of Cell-Free DNA

Bondi, Parker 30 November 2018 (has links)
Sepsis is a dysregulated systemic response to infection and is one of the leading causes of in-hospital mortality in Canada. Accurate distinction between survivors and non-survivors of sepsis has recently been demonstrated through quantification of cell-free DNA (cfDNA) concentration in blood. In an analysis of 80 septic patients, non-survivors of sepsis had significantly higher cfDNA concentration levels than that of survivors or healthy patients. Real time separation of cfDNA from contaminants in blood has also been done using a cross channel microfluidic device. Current methods for DNA quantification utilize time consuming and complicated laboratory equipment and therefore are not suitable for bedside real-time testing. Thus a handheld cfDNA fluorescence device coined the Sepsis Check was designed that can perform DNA characterization in a reservoir device and DNA detection in a microfluidic cross channel device. The goal is to use this system along with the cross channel devices to set apart survivors or healthy donors from non-survivors in patients with sepsis. The design consists of a 470𝑛𝑚 light emitting diode (LED) with 170𝑚𝑊 of optical power (LED470L – ThorLabs), an aspherical uncoated lens with a focal length of 15𝑚𝑚 (LA1540-ML – ThorLabs), a 488𝑛𝑚 bandpass filter with a 3𝑛𝑚 full width at half maximum (FWHM) (FL05488-3 – ThorLabs), an aspherical uncoated lens with a focal length of 25𝑚𝑚 (LA1560-ML – ThorLabs), an aspherical uncoated lens with a focal length of 35𝑚𝑚 (LA1027-ML – ThorLabs), a 525𝑛𝑚 longpass filter with an optical density >4.0 (F84744 – Edmund Optics), and a Raspberry Pi Camera V2 (Raspberry Pi Foundation). The Sepsis Check is made to excite the dsDNA specific PicoGreen fluorophore which has a peak absorbance at 502𝑛𝑚 and a peak emission at 523𝑛𝑚. In summary, the Sepsis Check in this thesis is capable of calibrating dsDNA concentration from 1𝜇𝑔/𝑚𝐿 to 10𝜇𝑔/𝑚𝐿 and detect DNA accumulation of 5𝜇𝑔/𝑚𝐿 and 10𝜇𝑔/𝑚𝐿 in the cross channel device. This tool can be a valuable addition to the ICU to rapidly assess the severity of sepsis for informed decision making. / Thesis / Master of Applied Science (MASc)
8

Wireless Sensor System for Airborne Applications

Pellarin, Steve, Grossman, Hy, Musteric, Steven 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / Adding an instrumentation / telemetry system to a test article has historically required an intrusive installation. Power, wiring, and available space typically present significant challenges. There has been a long-standing need in the test and training community for a non-intrusive, flexible and modular instrumentation and telemetry system that can be installed on an aircraft or other test article without the need for permanent modifications. In addition, as available space in aircraft weapon bays, small weapons, and unmanned vehicles becomes a premium, the miniaturization of remote sensors and telemetry units becomes critical. This paper describes the current status of the Advanced Subminiature Telemetry System (ASMT) Initial Test Capability Project. It discusses the progress to date in fielding an operational, wireless sensor system that may be installed on the aircraft skin using an Electro-Cleavable adhesive as an alternative to conventional mounting methods. The wireless sensor utilizes the Wireless Communications Standard for Wireless Personal Area Network™ (WPAN™) IEEE 802.15 Working Group standard (commonly referred to as Bluetooth) to establish communication between the sensor and controller modules. Results of aircraft ground testing for EMI compatibility with aircraft systems will be presented. It is also expected that actual flight test results will be available by the time the paper goes to publication.
9

WIRELESS SENSOR SYSTEM FOR AIRBORNE APPLICATIONS

Pellarin, Steve, Musteric, Steven 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Adding an instrumentation / telemetry system to a test article has historically required an intrusive installation. Power, wiring, and available space typically present significant challenges. There has been a long-standing need in the test and training community for a non-intrusive, flexible and modular instrumentation and telemetry system that can be installed on an aircraft or other test article without the need for permanent modifications. In addition, as available space in aircraft weapon bays, small weapons, and unmanned vehicles becomes a premium, the miniaturization of remote sensors and telemetry units becomes critical. This paper describes the current status of the Advanced Subminiature Telemetry System (ASMT) Initial Test Capability Project. It discusses the challenges that have been overcome in developing a wireless sensor network system for use in an airborne test environment. These include wireless sensor packaging design, selection of operating frequencies, COTS wireless devices, batteries, system synchronization and data bandwidth calculations. The paper will also document the progress to date including preliminary test results.
10

Desenvolvimento de equipamento de teste de estruturas miniaturizadas: testes em estrutura útil na eliminação de partículas. / Development of machine to test miniaturized structures: tests in util structure from particles elimination.

Santos, Leandro Colevati dos 26 May 2006 (has links)
Amostras com pequenos volumes e matrizes complexas, como sistemas biológicos, necessitam de preparação criteriosa. Muitas dessas amostras são melhor analizadas em estruturas miniaturizadas devido à necessidade de detectar células e microorganismos em diferentes matrizes. Por essa razão, equipamentos capazes de detectar e destruir microorganismos e estruturas para prévia retenção desses se faz necessários na vida moderna. Chicanas, constrições usadas para reduzir velocidade de fluxo, que podem ser utilizadas para reter compostos, são estruturas macroscópicas para remover resíduos de lagos, fazendas e etc. e chicanas miniaturizadas foram usadas para a adsorção de compostos orgânicos do ar e da água. Assim, esse trabalho tem dois diferentes objetivos: 1) Produção de um equipamento de baixo custo, para teste de partículas ou eliminação de microorganismos e 2) O desenvolvimento de estruturas miniaturizadas para retenção e/ou seleção de partículas e substâncias viscosas de um fluido líquido. A metodologia utilizada foi: 1) Dois software foram escolhidos para esse trabalho. O LabVIEW® 7.0 foi utilizado como plataforma para o desenvolvimento do software do equipamento e o FemLAB® 3.1 para a simulação de estruturas. O equipamento produzido usou Microbalança de Quartzo como detector e um sistema de admissão baseado em uma bomba e tubos. 2) O desenho da estrutura foi otimizado por simulação do comportamento do fluxo. A estrutura otimizada foi feita desmontável, e usinada em polimetilmetacrilato ? acrílico, com ferramentas convencionais. Acrílico foi usado devido à sua transparência óptica, que permite testes com microsocpia óptica. As simulações consideraram N2 e Água como fluidos gasoso e líquido, respectivamente. Avaliou-se o comportamento das partículas (50?m and 13?m) em fluxo gasoso e polidimetilsiloxano (silicone, com viscosidade de 350 cSt) e partículas em fluxo líquido. As estruturas foram caracterizadas quanto à adsorção e retenção de partículas usando equipamento desenvolvido e por microscopia óptica. As estruturas foram, também, continuamente fotografadas durante a execução do experimento e fotos foram utilizadas para determinar o comportamento do fluxo. Os reagentes foram injetados na estrutura em pequenos pulsos. O equipamento mostrou boa performance para detecção de adsorção em fluxo líquido e reprodutibilidade no monitoramento do aquecimento de estruturas. As chicanas mostraram boa capacidade de reter partículas grandes (50?m), mas não pequenas (13?m), tanto para fluxos gasosos como líquidos. Contudo, a estrutura tem pequena capacidade de carga para fluidos líquidos (? 1mg); além disso, a retenção de amostras de silicone na estrutura, utilizando fluido líquido, ocorreu devido à diferença de velocidade entre os fluidos. A simulação e os resultados experimentais apresentam boa correlação. Assim, a chicana mostrou a possibilidade de, seletivamente, separar partículas em fluxos gasosos e líquidos ou reter substâncias viscosas em fluxo líquido. Esses resultados apontam para diversas aplicações, como por exemplo, pré-tratamento para análises biológicas e retenção ou eliminação de microorganismos. / Samples with small volume and complex matrix, such as biological systems, require careful preparation. Many of these samples are better analyzed in miniaturized structures owing to the need of detect cells and microorganisms in different arrays. Therefore equipment able to detect and destroy microorganisms and structures to previously retain them are require in the modern life. Chicanes, i.e. constrictions used to reduce flow velocity, can be useful to retain compounds, are macroscopic devices to remove waste removal from lakes, farms, etc. and miniaturized chicane was used to adsorption of organic compounds from air and water. Thus, this work has two different targets: 1) Production of a low-cost equipment useful for tests of particle or microorganisms elimination and 2) The development of miniaturized structures useful for retention and/or selection of particles and viscous substances from a liquid flow. The methodology used was: 1) Two software were chosen to this work. The LabVIEW® 7.0 was used for development of equipment software and FemLAB® 3.1 for structures simulation. The equipment production used Quartz Crystal Microbalance as detector and an admission system based on simple pumps and plumbing. 2) The design of the structure design was optimized using flow simulation. The optimized design was manufactured in poly(methyl methacrylate) -acrylic, with conventional tools. Acrylic was used due to the optical transparency that allows photographic tests and the structures can be easily disassembled. The simulations considered nitrogen and water for gaseous and liquid flow, respectively. It was evaluated the behavior of particles (50?m and 13?m) on gaseous flow and polydimethylsiloxane (silicone, viscosity of 350 cSt) and particles on liquid flow. The structures were characterized using equipment produced to measure adsorption and optical microscopy to evaluate particle retention. The structures were also continuously photographed during the experiments and the photos were analyzed to determine flow behavior. The reactants were inserted in the structure in small pulses. The equipment shows good performance for detection of adsorption in liquid flows and reproducibility on monitoring heated structures. Chicanes showed good ability to retain big particles (50 ?m) but not small ones (13 ?m) for both liquid and gaseous flow. However, the structure has small load capacity for liquids (? 1 mg). Moreover, the retention of silicone samples in the structure on liquid flow occurs due to the difference in the fluid velocity. The simulation and experimental results are in good agreement and also chicane structure shows the possibility of selectively separate particles from gaseous and liquid flow or retain viscous substances from a liquid flow. These results point out to several applications, such as sample pretreatment for biological analysis and microorganism retention or elimination.

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