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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.
221

Suitability Layers for Mesonet Stations in Tennessee

Holmes, Tristan, Joyner, Andrew, Tollefson, Will 25 April 2023 (has links) (PDF)
Mesonet stations are environmental monitoring systems used to examine environmental features such as Precipitation, Temperature, Insolation, Soil Moisture, and Localized Hazards. network of Mesonet stations is an integral part of weather and climate monitoring and the data produced are essential for agriculture, planning, transportation, and other industries. Tennessee is one of the few states without a Mesonet; a bill currently before the state assembly includes funding for such a system. Therefore, this research describes development of a Mesonet suitability layer for Tennessee that can be used to guide placement of individual Mesonet stations across the state, taking into account spacing, terrain, land use, construction suitability, and other factors. Land cover, road centerline, roughness, elevation, flood zone, building footprint, and soil type data were obtained from USGS, FEMA, NLCD, and the Tennessee state database to create each layer. Using ArcGIS Pro, each data layer was converted to a raster and then masked to the state of Tennessee at 30-meter resolution to ensure proper alignment of data overlays. The combined overlay map will identify zones that meet suitability criteria, and it is expected that multiple areas in each county will meet the such that a complete Mesonet network can be sited across the state. This study provides important information needed for final placement of Tennessee’s future Mesonet stations, which will provide essential weather and environmental monitoring data important for Tennessee.
222

Infrastructure Monitoring through Frequency Change Detection using Infrasound

Whitlow, Robin Danielle 03 May 2019 (has links)
As transportation infrastructure continues to age, new methods of non-contact monitoring should be evaluated and, if found suitable, employed for bridge monitoring and structural health assessment. This study highlights the use of infrasound monitoring, a geophysical technique utilizing acoustics below 20 Hz, as one possible solution for non-contact, non-line-of-sight infrastructure health monitoring. This dissertation focuses on the technique of infrasound for infrastructure monitoring (bridges are of primary interest) beginning with a literature review and an overview of current operational considerations for infrasound for infrastructure monitoring developed at the U.S. Army Engineer Research and Development Center. A meta-analysis of bridge vibrational characteristics was completed following identification of a gap in the knowledge base in this area. This completed meta-analysis compared vibrational characteristics across multiple bridge types and construction materials to determine applicability of infrasound for detection and monitoring of each bridge type. With these considerations in mind, an experimental series involving a steel, two-girder bridge in northern California was completed using infrasound to detect natural modes of the structure and validated by on-structure accelerometers. The non-contact nature of this structural assessment approach has potential to supplement traditional structural assessment techniques as affordable, remote, persistent monitoring of transportation infrastructure. Upon completion of the original experimental series, the data were used to investigate the possibility of wide area monitoring using infrasound, including possible limitations and boundaries. Overall implications for use of this technology are also discussed for a multiple infrastructure types.
223

Automotive Battery State-of-Health Monitoring Methods

Grube, Ryan J. January 2008 (has links)
No description available.
224

Evaluation of Green Stormwater Infrastructure Monitoring Protocols

Cetin, Lauren Marie 21 June 2018 (has links)
Due to development of once natural landscapes, also referred to as urbanization, stormwater management has evolved in an effort to address and counteract impairment of waterways in the United States by extensively implementing best management practices (BMPs) or Green Stormwater Infrastructure (GSI). Facilities are installed without any requirement of long-term monitoring; instead relying on lab-tested or assumed pollutant removal efficiencies that often do not translate into field implementation and do not perform as intended and required by regulatory agencies. Monitoring studies have often been applied with variable standards, which lead to inconsistent results and inconclusive data. This study aims to synthesize essential components of a GSI monitoring program based on a review of existing programs (Technology Assessment Protocol – Ecology [TAPE], Technology Assessment Reciprocity Partnership [TARP], etc.). Data from past protocols was used in tandem with historic precipitation data to develop a methodology for creating a local or small region-specific protocol. This methodology was applied to the case study area of Fairfax, Virginia. Results from the study indicate that historic precipitation data and past protocol recommendations can be effectively applied in a local setting to create a more suitable protocol adapted for GSI monitoring in order to confirm designed efficiency. / Master of Science / Due to development of once natural landscapes, also referred to as urbanization, stormwater management has evolved in an effort to address and counteract impairment of waterways in the United States by extensively implementing best management practices (BMPs) or Green Stormwater Infrastructure (GSI). Facilities are installed without any requirement of long-term monitoring; instead relying on lab-tested or assumed pollutant removal efficiencies that often do not translate into field implementation and do not perform as intended and required by regulatory agencies. Monitoring studies have often been applied with variable standards, which lead to inconsistent results and inconclusive data. This study aims to synthesize essential components of a GSI monitoring program based on a review of existing programs (Technology Assessment Protocol – Ecology [TAPE], Technology Assessment Reciprocity Partnership [TARP], etc.). Data from past protocols was used in tandem with historic precipitation data to develop a methodology for creating a local or small region-specific protocol. This methodology was applied to the case study area of Fairfax, Virginia. Results from the study indicate that historic precipitation data and past protocol recommendations can be effectively applied in a local setting to create a more suitable protocol adapted for GSI monitoring in order to confirm designed efficiency.
225

Influence of ethnicity on acceptability of method of blood pressure monitoring: a cross-sectional study in primary care

Wood, S., Greenfield, S.M., Haque, M.S., Martin, U., Gill, P.S., Mant, J., Mohammed, Mohammed A., Heer, G., Johal, A., Kaur, R., Schwartz, C.L., McManus, R.J. 15 March 2016 (has links)
Yes / Ambulatory and/or home monitoring are recommended in the UK and North America for the diagnosis of hypertension but little is known about acceptability. To determine the acceptability of different methods of measuring blood pressure to people from different ethnic minority groups. Design and setting : Cross sectional study with focus groups in primary care. Methods: People with and without hypertension of different ethnicities were assessed for acceptability of clinic, home and ambulatory blood pressure measurement using completion rate, questionnaire and focus groups. Results: 770 participants were included comprising white British (n=300), South Asian (n=241) and African Caribbean (n=229). White British participants had significantly higher successful completion rates across all monitoring modalities compared to the other ethnic groups, especially for ambulatory monitoring: white British (277 completed, 92%[89-95%]) vs South Asian (171, 71%[65-76%], p<0.001 and African Caribbean (188, 82%[77-87%], p<0.001) respectively. There were significantly lower acceptability scores for minority ethnic participants across all monitoring methods compared to white British. Focus group results highlighted self-monitoring as most acceptable and ambulatory monitoring least without consistent differences by ethnicity. Clinic monitoring was seen as inconvenient and anxiety provoking but with the advantage of immediate professional input. Conclusions: Reduced acceptability and completion rates amongst minority ethnic groups raise important questions for the implementation and interpretation of blood pressure monitoring in general and ambulatory monitoring in particular. Selection of method for blood pressure monitoring should take into account clinical need and patient preference as well as consideration of potential cultural barriers to monitoring. / NIHR
226

Using the Ground Equipment Monitoring Service (GEMS) for Satellite Telemetry & Command Systems

Andzik, Rob 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 / As satellite ground systems migrate toward network-centric, distributed architectures, controlling remote ground equipment becomes a central issue. While many protocols and approaches exist that address remote control and status, there is little agreement on a common solution. Device vendors and system integrators commonly find themselves integrating multiple protocols to meet a wide range of requirements. Technologies change and new protocols evolve that result in yet more options to be considered. However, the fundamental aspects of device control remain constant. The Ground Equipment Monitoring Service (GEMS) seeks to define a standard model for device control independent of the underlying protocols and technologies. Using this approach, a wide range of protocols can be mapped to the GEMS model. Systems using different protocols can then rely on the common mapping and utilize translators to connect heterogeneous components with little integration costs. This paper describes the state of the specification and potential uses of the GEMS specification in Satellite Ground Systems. Interactions between the GEMS specification and other standards such as the CCSDS SLE Complex Management services are also presented.
227

Right ventricular function in paced patients : a study using pulsed Doppler ultrasound

Cheesman, M. G. January 1991 (has links)
There is increasing interest in right ventricular function as an important determinant of cardiac output. However, the chamber is difficult to study, because of its shape and relationship to the left ventricle. Invasive studies, radionuclide studies and two-dimensional echocardiography are all useful approaches, but all have serious limitations. Systolic time intervals, best measured by pulsed Doppler ultrasound in the proximal pulmonary artery, offer one method of assessing right ventricular systolic function. Previous "normal" ranges, however, could be criticised on many counts. I present data from carefully checked normal controls and compare to previous publications, and explore variability and relationships between the various systolic time intervals. Most variables have skewed frequency distributions; the ranges are somewhat wider than previously described; most heart rate corrections are found to have serious limitations; and the effect of age is explored. Complete heart block offers a model to study the the effects of varying atrioventricular intervals whilst the ventricular rate is held unphysiologically steady by an artificial pacemaker. Given the current controversy about the merits of single- versus dual-chamber pacing, the issue is of topical interest also. The effect of varying the "P-R" interval within the physiological range is explored, and "optimal" ranges identified. A curious "nadir" effect, previously unknown, was discovered. When P waves followed paced QRS complexes at about 50-100ms, forward flow into the pulmonary artery (as judged from systolic time intervals) fell in most patients, and in some subjects virtually ceased. As a small included invasive part of the study showed, this was accompanied by falls in RV systolic pressure and rises in right atrial pressure. This study demonstrates that right ventricular systolic time intervals can be used to study right ventricular function in pacing situations, and is further evidence of the unsatisfactory nature of single-chamber ventricular pacing.
228

FLIGHT TEST MONITORING OF AVIONIC FIBRE CHANNEL NETWORKS FOR RECORDING AND TELEMETRY

Zettwoch, Robert N. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The F/A-18E/F Super Hornet fighter aircraft program is currently flight testing a Fibre Channel Network (FCN), which will initially replace certain Avionics Systems’ MIL-STD-1553 communications. The Advanced Mission Computers and Displays (AMC&D) and the Active Electronically Scanned Array (AESA) RADAR are replacing their MIL-STD-1553 counterparts to fulfill performance enhancements and growing data requirements. The maximum amount of data that can be transferred between these systems is significantly increasing. Each remote terminal on a MIL-STD-1553 bus can transmit or receive approximately 1Mbps. Each node on a FCN can simultaneously transmit and receive 1Gbps. With a Fibre Channel Network Switch (FCNS), multiple systems can communicate concurrently, thus increasing overall system throughput even further. Several other systems will be replaced in the near future utilizing the FCNS. The Fibre Channel Interface Unit (FCIU) was designed for the F/A-18E/F AESA program as a nonintrusive way to monitor multiple nodes, extract node specific information, and record this information using conventional on-board recorders. In order to reduce the risks associated with developing hardware and software concurrently with the Avionic System’s protocol, the FCIU was developed as an upper-level-protocol (ULP) (layer FC-4) independent device. Two big advantages of ULP independence are the avoidance of complex protocol programming for each different type of monitored network system and the non-intrusive nature of the FCIU connection to the FCN. This facilitates the quick installation of the FCIU to monitor any FC network and the FCIU IRIG-106 PCM type output lends itself to be integrated quickly into a typical Flight Test data recording or telemetry system.
229

Calibration and error definition for rotary motion instrumentation using an incremental motion encoder (IME)

Hatiris, Emmanouil January 2001 (has links)
Condition based monitoring is widely used for the determination of the health of machines. The Nottingham Trent University Computing Department has developed a new system, the Incremental Motion Encoder (!ME), which is based on the time interpolation of the digital signals produced by an optical encoder. Experiments have shown that the !ME can be used as a condition based maintenance sensor as it is possible to detect rolling element defects, an unbalanced shaft and oil contamination of a bearing. The system uses a geometrically configured optical device to scan a precision encoder disc and Digital Signal Processing technology is used to interpret the signals. Previous work has demonstrated the qualitative usefulness of the 1ME. However, further work was needed to assess the accuracy of the measurements, to analyse the principles of the 1ME, to validate the performance of the existing device and to develop methods for error definition and error compensation. Testing and experimentation on the existing experimental system have been carried out by the Candidate and an understanding gained of the device. The sources of error of the 1ME have been identified, which had not been quantified previously. Measuring and compensating for the three main sources of error, read head position, eccentricity of the encoder disc and encoder abnormalities are the three major tasks of the project. Modifications to the experimental rig have been developed in order to allow these tasks to be addressed. The Candidate has developed three different types of techniques to measure the position error of the read heads. A pattern recognition method was developed and is successful for 1ME systems that use an encoder disc with significant grating line errors. A second method using Fast Fourier Transform (FFT) has been developed to exploit the fact that the difference in the phase angles, obtained using a FFT, gives the angle between the read head positions. The new experimental system is now able to obtain the angular position of the read heads by using the index grating line. The third method relies on the presence of the index grating line on the encoder disc which may not be present in all systems. Eccentricity of disc centre relative to the centre of rotation affects the correct calculation of the angular position of the encoder disc. Algorithms have been developed by the Candidate in order to compensate for this type of error. Experimental results have shown that angular position error can be corrected successfully. The Candidate has developed methods for detection of small abnormalities of the encoder disc by using a multiple averaging technique. Computational algorithms have been developed to correct the encoder disc abnormalities by using individual information from each read head, promising results have been obtained from the experimental 1ME. An 1ME device can be tailored to fulfil the desired requirements of resolution, bandwidth and accuracy. A self calibration instrument can be developed by using the previously mentioned techniques in order to self calibrate and increase the accuracy and reliability of an IME's results.
230

A near infrared holographic glucose sensor for diabetes management

Vezouviou, Evangelia January 2014 (has links)
No description available.

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