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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

A novel apparatus for estimating pesticide volatility from spray droplets

Poel, Jeff D. 04 December 1996 (has links)
Graduation date: 1997
2

Design of a cross-correlator for process measurements

Rahimzadeh, Bizhan January 1989 (has links)
No description available.
3

Development of methodology and instrumentation for determination of chloroform in water

Yang, Ying, 1969- 17 June 1997 (has links)
Graduation date: 1998
4

Análise de três métodos de estimativa da evapotranspiração de referência para a região de Pradópolis - SP

Balotta, Graciano Augusto Peviani [UNESP] 10 November 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-11-10Bitstream added on 2014-06-13T19:28:59Z : No. of bitstreams: 1 balotta_gap_me_jabo.pdf: 233319 bytes, checksum: 23b0129b8a38f43d1dd6a512cb94ef29 (MD5) / O objetivo desse trabalho foi avaliar três métodos de estimativa da evapotranspiração de referência (Hargreaves, Radiação Solar e Makkink), comparando-os com o método de Penman-Monteith, recomendado pela Organização das Nações Unidas para a Alimentação e Agricultura (FAO) como método padrão para estimativa da ETo, para o município de Pradópolis - SP. Para esse fim foi instalada no posto agrometeorológico da cidade de Pradópolis - SP uma estação meteorológica automatizada. Por intermédio desta estação foram obtidas medidas da radiação solar global, temperatura do ar, umidade relativa do ar e velocidade do vento. A análise dos resultados foi feita por uma técnica que considera os erros da ET0. O resultado da avaliação dos métodos indica um melhor ajuste para estimativa da ETo para o método de Hargreaves. Os métodos de Makkink e Radiação Solar não obtiveram um ajuste satisfatório com o do Penman-Monteith. Para avaliar métodos de estimativa da evapotranspiração deve-se considerar os erros da estimativa da ETo, evitando possíveis erros de avaliação / The aim of this investigation was to evaluate two reference methods to Monteith method, recommended by the Food and Agricultural Organization of the United Nations (FAO) as the standard method for estimating ETo in Pradópolis - SP. To this data collection, an automated weather station was installed in the meteorological station at Pradópolis - SP. Through estimate evapotranspiration (Hargreaves, Radiation and Makkink), compared to Penman-this station, we obtained measures of global solar radiation, air temperature, relative humidity and wind speed. The analysis was done by a technique that considers the mistakes of ETo, which depends on the combination of the errors of the variables that make up the estimating equations, derived from the measurement instruments used to obtain these variables. The aftermath showed a better adjustment to Hargreaves. Makkink, and Radiation methods are different from Penman-Monteith, therefore, they cannot be compared. To evaluate methods to estimate evapotranspiration and avoid possible evaluation errors, ETo estimate errors must be considered
5

An examination of the dimensionalities and common constructs of selected adult cognitive learning style instruments

Hardy, Christopher R. 19 September 2008 (has links)
Though a widespread advocacy exists for the use of learning style instruments in adult education, accurate measurement and interpretation using existing instrumentation have proven problematic. Additionally, relatively little attempt has been made to empirically reconcile the different theoretical and conceptual frameworks underlying these instruments. The purpose of this study was to examine the dimensionality, reliability, and construct validity of a cognitive learning style semantic differential instrument, the Cognitive Preference Pattern Indicator (CPPI), and at the same time to examine three instruments commonly used with adults for assessing cognitive learning style, the Myers-Briggs Type Indicator (MBTI), the Success Style Profile (SSP), and the Gregorc Style Delineator, with respect to factor structure and shared learning style constructs. Over 1900 protocols from 1411 adults were used in the analyses. The examination of the CPPI produced clearly acceptable internal reliability coefficients on all scales and relatively strong evidence of construct validity in the internal and comparative factor analyses. Separate internal factor structures were examined for each instrument. Though not all of the other instruments' internal structures completely supported their respective theoretical bases, enough internal structures emerged for an analysis of common constructs. A combined factor analysis of the four instruments yielded a robust three factor solution which was consistent with an information processing model framework for clearly describing individual differences in regard to cognitive learning styles. The clear relationships of this model revealed strong empirical support to the theoretical bases of the CPPI and offered the adult education community a simple, valid, and profound conceptualization of cognitive learning styles. / Ph. D.
6

Parental perception of effectiveness of Q-sort methodology in measuring attachment in children with atypical behaviors

Hosch, India A. 06 June 2008 (has links)
The effectiveness of the Attachment Behavior Q-Sort in measuring attachment in children with atypical behaviors was examined in this study. Data collected from interviews, structured and unstructured observation, and parental sorting of the Q-Sort by ten families provided insight about the effectiveness of the instrument and attachment behaviors. The Maternal Behavior Q-Sort was also completed by the investigator to provide additional information about maternal qualities in this population. Results of this study indicate the Attachment Behavior Q-Sort with modification of some statements may be effective in measuring attachment behaviors of some members of this population. Because this instrument uses aspects of mobility to measure attachment behaviors, its usage with children who have mild to severe limitations in physical mobility is very questionable. Additional findings indicate social support may be a factor in influencing the interaction patterns of mothers and thus may also impact on the development of the attachment relationship. / Ph. D.
7

Medial surface transformations for rapid approximation of casting solidification

Houser, Scott A. 07 October 2005 (has links)
This thesis demonstrates the feasibility of using a medial surface transformation as a tool to rapidly approximate the solidification patterns of convex faceted solid models of castings. The medial surface transformation is used to automate the greatest included sphere approach to solidification pattern approximation. The experimental software of this thesis extracts the medial surface transformation from a convex faceted model by computing the model's Voronoi diagram and uses it to identify casting hot spots and cooling patterns. Comparison with a finite difference method (FDM) solution showed that the locations and shapes of hot spots predicted by FDM converge to the shapes and locations predicted by the experimental software. / Master of Science
8

Development and evaluation of sampling techniques, instrumentation, and pyridine derivative reagents for fluorometric determination of chloroform and TCE in water with a portable fluorometer

Prayoonpokarach, Sanchai 24 April 2003 (has links)
A novel, portable, filter fluorometer was developed for the determination of chloroform and TCE at environmentally-relevant levels when coupled with improved sampling techniques and reagents. Reagents selective for the TCE or chloroform convert these toxic species into fluorescent species that can be monitored. The fluorometer is based on LED excitation light sources, a battery-operated photomultiplier tube as a radiation detector, and appropriate excitation and emission filters. A unique low-power, miniature heater inside the cell holder of the fluorometer provides control of the temperature of the reagent solution above ambient temperature. The fluorometer and the sampling systems, including a miniature air pump, are portable and can be operated from a small lead battery over an entire day. Sparging, passive transfer, and membrane sampling techniques were used to transfer TCE or chloroform from the sample solution as a vapor into the appropriate reagent and to provide preconcentration. The apparatus for membrane sampling was improved to be applicable for continuous sampling of water in the field situations with minimal sample manipulation. Each of the three sampling techniques provides a transfer rate of the analyte of ~1 ng/min per ng/mL of analyte in the sample. The optimized reagent based on 1-(3-pyridylmethyl)urea provides high selectivity to chloroform and the reagent based on isonicotinamide has excellent selectivity to TCE. These two reagents serve as an alternative to the more common pyridine reagent for the determination of chloroform or TCE in water and eliminate the exposure of the user to toxic pyridine vapor. The developed filter fluorometer, the optimized reagents, and the membrane sampling technique provide a detection limit for chloroform of 0.2 and 10 ng/mL, respectively, with the pyridine and 1-(3-pyridylmethyl)urea reagent. The detection limit for TCE is 0.3 ng/mL with the isonicotinamide reagent. For TCE, the detection limit is almost two orders of magnitude better than obtained previously with a fluorometric technique. Analysis times vary from 15 to 30 min. / Graduation date: 2003
9

Comparison of body composition using the Bod Pod and dual-energy x-ray absorptiometry before and after weight loss

Weyers, Anna M. January 2000 (has links)
No research has been performed comparing percent body fat measurements using dual energy x-ray absorptiometry (DEXA) and air plethysmography after weight loss. The purpose of this investigation was to compare body composition assessments using the Bod Pod® Body Composition System (BP) and the DEXA ProdigyTM before and after an 8-week weight loss diet and exercise program. Based on prior comparison studies, it was hypothesized that percent fat values would be significantly lower using the BP compared to the DEXA before and after weight loss. Also since both methods have been shown to be reliable, it was hypothesized that the BP and DEXA would detect similar changes in percent fat in response to a weight-loss intervention. Twelve women (42 ± 8 yrs) and ten men (40 + 11 yrs) had their percent body fat estimated using the BP and whole body DEXA ProdigyTM scanner. A similar significant (P < 0.05) decrease in percent body fat was observed using the BP and DEXA ProdigyTM (-2.2% and -1.8%, respectively) after weight loss. Percent body fat using the BP was significantly lower than the DEXA ProdigyTM before (36 ± 10.7% and 38.1 ± 9.4%, respectively) and after (33.8 ± 10.8% and 36.3 + 10.6%, respectively) the weight loss program. Significant Pearson correlation coefficients between the DEXA ProdigyTM and the BP were noted pre (r = 0.975) and post (r = 0.968) weight loss. These data indicate the BP provides significantly lower absolute %fat values within a range of body fat levels (20-56%) when compared to the DEXA. However, the BP and DEXA detect similar changes in %fat, fatfree mass, and fat mass from weight loss in men and women. Also, the BP consistently overestimated fat-free mass and underestimated %fat and fat mass compared to values obtained from DEXA. / School of Physical Education
10

The measurement of the pressure distribution over the wing of an aircraft in flight

McCarty, Matthew, Aerospace, Civil & Mechanical Engineering, Australian Defence Force Academy, UNSW January 2008 (has links)
A measurement system has been developed for use on a light aircraft to measure the pressure distribution over the wing surfaces. The measurement system was developed as a low-cost alternative to existing advanced measurement systems. The system consisted of low profile, low cost pressure sensors that interfaced digitally with microcontrollers for data acquisition. The pressure sensors and microcontrollers were developed into self-contained sensor modules with all electronic components mounted on flexible circuit board that formed the base of the modules. Two types of module were developed; a module with a single pressure sensor and a module with a row of seven pressure sensors at fifteen millimetre spacing. The total cost of the sensor modules was approximately ninety dollars for a single sensor module and one hundred and forty dollars for the seven sensor module. Studies were carried out using numerical methods to predict the pressure distribution over a NACA2412 airfoil. The numerical studies were used to evaluate the effect of adding the sensor modules to the wing, and the effect of the sensor distribution on measured force coefficients. Numerical predictions were made using the XFOIL software package. This software was validated using the Hess-Smith inviscid panel method. Flight testing was carried out with the pressure distribution measurement system to confirm the operation of the system and to make preliminary measurements. The flight testing focused on the measurement of steady state pressure distributions for comparison with the numerical predictions. Good agreement was found between the measured pressure distributions and the XFOIL predictions. Integration of the pressure distributions enabled comparison of normal force, lift force and quarter chord moment coefficients. The measured force coefficients showed the expected trends with angle of attack although it was found that the limited number of sensor modules used caused large error in the quarter chord moment coefficient compared to the numerical predictions.

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