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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.
741

The earliest instrument : ritual power and fertility magic of the flute in Upper Paleolithic culture

Neal, Lana Carol 02 March 2015 (has links)
The present study examines the earliest known musical instruments, Upper Paleolithic flutes. Flutes dating to the Upper Paleolithic period are the oldest musical instruments that have survived in the archeological record. These have been discovered at archeological sites in Europe dating from approximately 40,000 to 15,000 years ago. Although humans were most likely creating music prior to this time, the people who entered Europe approximately 40,000 years ago began to create musical instruments that have survived to the present day. This study investigates the significance and function of these instruments in Upper Paleolithic culture. Analysis of the artifacts is followed by discussions of archeological contexts, Upper Paleolithic art, ethnographic comparison, and the flute in mythology. Such diverse sources provide multiple layers of evidence regarding the role of the flute in Upper Paleolithic culture. The phallic shape of the instrument and the fact that it is played with the breath, also a symbol of life, connect the flute with the fertility of humans, plants, and animals, the cycle of life and death, and rebirth after death. There is evidence that the flute was intrinsically linked to these themes even in the Upper Paleolithic period, in which the flute was of vital significance, as it was magically imbued with the power to bestow life. / text
742

Determination of the hydraulic characteristics of unsaturated soils using a centrifuge permeameter

McCartney, John Scott, 1979- 28 August 2008 (has links)
A new experimental approach to determine the hydraulic characteristics of unsaturated soils using a centrifuge permeameter was developed in this study. Specifically, the centrifuge permeameter is used to determine the water retention curve (WRC), which quantifies the energy required to retain water in the soil pores during wetting and drying, and the hydraulic conductivity function (K-function), which quantifies the soil's change in impedance to water flow as it becomes unsaturated. An aim of this study is the promotion of using experimentally-derived hydraulic characteristics in engineering practice. Accordingly, the goals behind development of the centrifuge permeameter were a reasonable testing time, measurement of all variables relevant to water flow in unsaturated soils, and a methodology allowing straightforward interpretation of experimental data to determine the hydraulic characteristics. Development of the centrifuge permeameter was guided by lessons learned from an evaluation of previous characterization approaches. Specifically, issues such as the use of steady-state or transient water flow, boundary condition effects, and the use of instrumentation were evaluated in conventional tests to better develop the centrifuge permeameter. Steady-state infiltration of water through a soil specimen instrumented with tensiometers to measure matric suction and time domain reflectometry to infer moisture content was found to be the most reliable means of characterization. Steady-state water flow permits straightforward, repeatable interpretation of instrumentation results, boundary conditions, and flow data to determine the hydraulic characteristics. Centrifugation is employed to decrease the time required to reach steady-state water flow through a soil specimen by imposing a centripetal acceleration on the infiltrating water. The water infiltration rate and centripetal acceleration can be independently controlled in the centrifuge permeameter in order to reach different target hydraulic conductivity values. Continuous, in-flight measurement of the variables relevant to hydraulic characterization is possible through an on-board data acquisition system. The experimental component of this study is focused on validation of the centrifuge permeameter and verification of the hydraulic characteristics obtained using this approach. Simultaneous determination of the WRC and K-function for a clay of low plasticity was found to be possible in less than a week using the centrifuge permeameter, whereas several months were required in conventional tests. Consistent measurements of hydraulic conductivity were obtained using this approach, and little hysteresis was observed in the hydraulic characteristics. Additional experiments were performed to evaluate the validity of different assumptions required to interpret the experimental data and different issues in centrifuge testing. Two major assumptions required in previous centrifuge permeameter approaches were evaluated using the instrumentation available in the centrifuge permeameter. During steady-state water flow in the centrifuge, the suction and moisture content were found to be relatively uniform along the longitudinal axis of the permeameter, and the outflow boundary was found to have a negligible influence on the suction profile. Settlement under the increased body forces in the centrifuge were found to be negligible for the soil investigated in this study. The hydraulic characteristics were found to be sensitive to the calibration of the transducers and sensors used to infer the water pressure and moisture content during centrifugation. Overall, the expeditious, direct determination of the hydraulic characteristics of unsaturated soils was successfully achieved using centrifuge technology. Accordingly, the centrifuge permeameter approach helps promote the use hydraulic characteristics of unsaturated soils in geotechnical engineering design.
743

Remote measurement of turf water stress and turf biomass

Kelly, Harold Lorain Jr., 1958- January 1989 (has links)
Increasing irrigation efficiency on turfgrass could help reduce water consumption on large turf facilities. Two experiments were conducted using perennial ryegrass (Lolium perenne (L.) Derby) to evaluate the potential of using remote sensing to estimate turf water status, predict daily evapotranspiration (ET), and estimate turf biomass. In the first experiment a crop water stress index, utilizing remotely sensed canopy temperature, were used to schedule irrigations on 6 of 10 drainage lysimeters. Three of the remaining lysimeters were irrigated used on meteorological estimates of ET calculated using a modified Penman equation. The results of this experiment were inconclusive due to inconsistent lysimeter drainage characteristics. The second experiment was conducted on a turf green with multiple heights to evaluate the potential for using canopy radiance to estimate turf biomass. These results showed that turf biomass could be estimated from a vegetative index (Red Ratio = Near Infrared/Red radiance) obtained through measurements of canopy radiance (r2 = 0.91).
744

An optical head for a magneto-optic disk test system

Bushroe, Frederick Nicholas, 1964- January 1989 (has links)
Design and operation of modular optical head for a magneto-optic test system are described. Alternate solutions to design problems are discussed. A 30mW semiconductor laser with an integrated 250MHz oscillator is selected. The oscillator is used to modulate laser read current for a reduction in laser feedback noise. A collimating lens with an appropriate focal length is chosen so the beam's truncation at the objective yields the maximum write power density. Astigmatism associated with the laser diode is reduced to 0.125 waves by defocusing the collimating lens and circularizing with an anamorphic prism pair. Head components are aligned within several minutes of arc by using alignment apertures and an autocollimator. Aberrations due to tilt between the disk and beam are examined and coma is found to be the major contributor.
745

Development of a brain computer interface (BCI) based intention detection approach for persons with limited neuro-muscular control.

Kalunga, Emmanuel K. January 2013 (has links)
M. Tech. Electrical Engineering / For the last 3 decades, interdisciplinary studies on the Brain Computer Interface (BCI) have grown in number. This common interest has been stirred up by recent developments in technology and opportunities seen in BCI. BCI systems provide an interface for communicating and controlling the physical environment, bypassing the normal neuromuscular pathways. They thus constitute an alternative means of control for the large population of people with limited to non-existent muscular abilities. Limitations in existing systems have prevented BCIs from being used in real life applications. New approaches are now being investigated with the aim of exporting BCI to home usage. This study investigates a BCI with realistic performances for practical home usage. It proposes a BCI to be used as a modality in a multimodal control of an exoskeleton.
746

Evidence-based mathematical maintenance model for medical equipment.

Khalaf, Abdelbaset Abdelrahem. January 2012 (has links)
D. Tech. Electrical Engineering. / Aims to develop a mathematical maintenance model for medical equipment for the purpose of analysing maintenance strategies to optimise maintenance of medical equipment.
747

"EU-kommissionen är inte FBI. Vad vill du att vi ska göra? Ska vi skicka en armé till Rumänien eller vad?"

Sandra, Saied January 2015 (has links)
The purpose of this essay is to do a case specific examination of the EU level implementation of the integration of Romanian Roma. The essay is divided into two parts. The first part of the essay constitutes a description of relevant European Union policy instruments and the current ambition to integrate the Romanian Roma. The second part of the essay is a qualitative text analysis based on debate articles published in the Swedish daily newspaper Dagens Nyheter. The articles are systematically categorized by different themes in order to try to analyze the reasoning and argumentation in this area. The aim of the qualitative analysis is to find the core of the debate and then try to compare it with the EU’s ambitions to integrate Romanian Roma.   The essay concludes that there are problematic aspects to the implementation of Romanian Roma integration. This essay shows one of these problematic aspects. It is a complicated problem without a single, given solution. Rather, there are a number of factors that contributes to the problem. The essay also offers some new facts that can constitute a basis for further research.
748

Reliability and relevance of market risk disclosures by commercial banks

Hodder, Leslie Davis 16 March 2011 (has links)
Not available / text
749

The astronomical observation system of 12" telescope: its automatic control system and astronomical application

饒勇, Rao, Yong. January 1997 (has links)
published_or_final_version / Physics / Master / Master of Philosophy
750

An esophageal multiprobe for temperature, ECG, and heart and lung sounds measurements

Tao, Teh-Ho January 1979 (has links)
No description available.

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