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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.
11

Risk assessment and evaluation of the conductor setting depth in shallow water, Gulf of Mexico

Tu, Yong B. 16 August 2006 (has links)
Factors related to operations of a well that impact drilling uncertainties in the shallow water region of the Gulf of Mexico (GOM) can be directly linked to the site specific issues; such as water depth and local geological depositional environments. Earlier risk assessment tools and general engineering practice guidelines for the determination of the conductor casing design were based more on traditional practices rather than sound engineering practices. This study focuses on the rudimentary geological and engineering concepts to develop a methodology for the conductor setting depth criteria in the shallow water region of the GOM.
12

Handbook for Assistant Orchestra Conductors in the United States

January 2014 (has links)
abstract: Currently, an aspiring assistant conductor is faced with a lack of information regarding the expectations and successful strategies in preparing to take on an assistant conductorship in the United States. A conductor's training in the United States focuses heavily on stick and rehearsal technique, score study, performance practice, and developing a deeper understanding of the administrative and logistical structure of the modern symphony orchestra - as it should be. Speaking as a an aspiring young conductor, I believe that, although these aspects of conducting are crucial for one's success in the field, two important aspects of a conductor's education are often not given an adequate amount of attention in the basic curriculum. These are: 1) Developing a clearer understanding of the official and unofficial functions of an assistant orchestra conductor in the United States; and, 2) Providing a model of the elements of a professional and highly effective press packet including: conducting footage, CV/resume, photographs, website, references and cover letter. The purpose of this project was to collect and present information that may inform an aspiring assistant orchestra conductor regarding the expectations of such a position and strategies to improve one's marketability for such a job in the United States. A handbook for the aspiring conductor was also created. / Dissertation/Thesis / D.M.A. Music 2014
13

The score study procedures of three collegiate wind band conductors

Feyes, Andrew Dean January 1900 (has links)
Doctor of Philosophy / Curriculum and Instruction Programs / Frederick Burrack / This study examined the characteristics of the score study processes implemented by three collegiate wind band conductors. Participants engaged in anticipatory discussion, think-aloud score study session, and a follow up interview to verify researcher inference and observation. Using a multiple case study methodology, the research focused on identifying the individual score study process of each conductor and the impact held beliefs and educational influences had on these processes. The research then compared cases to identify common and unique interactions across participants.
14

Load diagnostic of power lines to control and optimize the utilization of wind energy

Dyachuk, Eduard January 2010 (has links)
Master thesis in cooperation with High Voltage Valley (Ludvika) and VB Energi (Ludvika)
15

A Mechanical Model for Erosion in Copper Chemical-Mechanical Polishing

Noh, Kyungyoon, Saka, Nannaji, Chun, Jung-Hoon 01 1900 (has links)
The Chemical-mechanical polishing (CMP) process is now widely employed in the ultralarge scale integration chip fabrication. Due to the continuous advances in semiconductor fabrication technology and decreasing sub-micron feature size, the characterization of erosion, which affects circuit performance and manufacturing throughput, has been an important issue in Cu CMP. In this paper, the erosion in Cu CMP is divided into two levels. The wafer-level and die-level erosion models were developed based on the material removal rates and the geometry of incoming wafers to the Cu CMP process, including the Cu interconnect area fraction, linewidth and Cu deposition thickness. Experiments were conducted to obtain the selectivity values between the Cu, barrier layer and dielectric, and the values of within-wafer material removal rate ratio, β, for the validation of the new erosion model. It was compared with the existing models and was found to agree better with the experimental data. / Singapore-MIT Alliance (SMA)
16

Design of RFID Tag Antenna with High Impedance Surface Structure to Reduce Metallic Effect

Tsai, Wei-Kuo 20 June 2006 (has links)
In this study, we design and fabricate novel tag antennas, which can be used on the metallic surface for radio frequency identification systems. We first focus on the effects when the antenna is placed on the metallic surface. Based on the simulation results, we investigate how the parameters of the antennas are affected. The helps us find solutions to reduce the effects when the antennas are placed on the metallic surface. In order to conform to the IC chips of RFID and reduce the influence of metal objects, we use the structure of the dipole antenna is used as the basis of the novel tag antenna design. And we employ the high impedance surface periodic structure which behaves similarly to a perfect magnetic conductor in the design of the novel tag antenna. The novel tag antenna is able to work normally when it was attached on the surface of the carton or metallic object. Finally, the tag antenna is fabricated and measured in a chamber. The measured results agree with simulated ones well.
17

Design of the Miniature High Impedance Surface Structure to Reduce Metallic Effect on the RFID Tag Antenna

Lee, Jui-Ni 24 July 2008 (has links)
ABSTRACT In this study, the properties of the high impedance surface structure are studied. We proceed to design the low profile and miniature high impedance surface structure. In order to conform to the IC chips of RFID and reduce the influence of metal objects, we add a layer of electromagnetic band-gap (EBG) structure on the back of the antenna. The EBG behaves as a high impedance surface, similar to a perfect magnetic conductor. This property of the EBG structure is able to isolate the antenna and backside environment and reduce the metallic effect. In order to achieve the requirements of small size and low cost on RFID tag antenna, we design the miniature, low profile and low cost high impedance surface structure. In this study, we use the slots and chip capacitance to miniaturize the dimension. Both approaches can reduce the influence of metallic objects. Although using slots can reduce the metallic effect, it does not have the advantage of low profile. Using chip capacitor can miniaturize the dimension and reduce metallic effect effectively. It also has advantages of low profile, low cost and low sensitivity to the frequency of the tag antenna. Finally, the high impedance surface structures are fabricated and measured when they combine with the tag antenna attached to the metallic object. The measured results agree with simulated ones well.
18

Thin Film pH Measuring Device

Luo, Jia Unknown Date
No description available.
19

Wind tunnel studies on rotational effects in lightly-iced transmission line galloping

Fleming, Patrick Hugh 30 June 2010 (has links)
Overhead transmission lines are prone to undergo large amplitude, low frequency vibrations when exposed to freezing rain and steady side winds. These vibrations are referred to as galloping. They involve a dominant vertical motion in addition to twisting and horizontal swaying. Field reports indicate that the majority of galloping cases are associated with lightly-iced lines with thin ice accretions. Previous studies have failed to explain this trend satisfactorily. The present thesis involves a series of wind tunnel experiments to understand the rotational effects in lightly-iced transmission line galloping. The work to restore and upgrade the wind tunnel used for the experiments are also reported. Aerodynamic loads are measured first on a stationary model of a short, representative section of a lightly-iced conductor. Subsequently, automated controls force the model to undergo rotational oscillations, and the aerodynamic loads measured from these dynamic tests are compared to the stationary results. The airflow in both sets of experiments is visualised by using a laser-based system. The stationary test shows that the well-established den Hartog criterion for predicting vertical galloping does not explain why lightly-iced lines gallop. The dynamic experiments however confirm the presence of rotation-induced lift, unaccounted for by quasi-steady theory and the den Hartog criterion. This additional lift force increases the coupling between the rotational and vertical directions and may promote coupled aerodynamic instability. Visualisations indicate that the surface irregularities of the ice and the rotational motion are jointly responsible for the rotation-induced lift forces observed in the aerodynamic measurements.
20

Wind tunnel studies on rotational effects in lightly-iced transmission line galloping

Fleming, Patrick Hugh 30 June 2010 (has links)
Overhead transmission lines are prone to undergo large amplitude, low frequency vibrations when exposed to freezing rain and steady side winds. These vibrations are referred to as galloping. They involve a dominant vertical motion in addition to twisting and horizontal swaying. Field reports indicate that the majority of galloping cases are associated with lightly-iced lines with thin ice accretions. Previous studies have failed to explain this trend satisfactorily. The present thesis involves a series of wind tunnel experiments to understand the rotational effects in lightly-iced transmission line galloping. The work to restore and upgrade the wind tunnel used for the experiments are also reported. Aerodynamic loads are measured first on a stationary model of a short, representative section of a lightly-iced conductor. Subsequently, automated controls force the model to undergo rotational oscillations, and the aerodynamic loads measured from these dynamic tests are compared to the stationary results. The airflow in both sets of experiments is visualised by using a laser-based system. The stationary test shows that the well-established den Hartog criterion for predicting vertical galloping does not explain why lightly-iced lines gallop. The dynamic experiments however confirm the presence of rotation-induced lift, unaccounted for by quasi-steady theory and the den Hartog criterion. This additional lift force increases the coupling between the rotational and vertical directions and may promote coupled aerodynamic instability. Visualisations indicate that the surface irregularities of the ice and the rotational motion are jointly responsible for the rotation-induced lift forces observed in the aerodynamic measurements.

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