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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

Ultrasonic sensing design and implementation for detecting and interacting with human beings in an AI system

Faltpihl, Peter January 2012 (has links)
This thesis covers the work performed to implement a Sonar sensor solution to detect human beings on a robotic lamp. A previously available solution was evaluated, but had to be redesigned due to faulty electronics. New hardware was developed, together with software to control this hardware. A software implementation of this new Sonar sensor system was also developed, on the robotic lamp itself. The nature of this thesis was very practical, so this report will focus on describing the different design stages that were performed, together with a wide discussion about future improvements and work, in order to achieve a robotic lamp that interacts with a human in an interesting manner.
2

ULTRASONIC SIMULATION AND MEASUREMENTS WITH CUT-OFF FREQUENCY EXTRACTIONS

ADEOGUN, KAZEEM 04 January 2013 (has links)
The removal of the effect of imperfect dynamic properties of ultrasonic transducers and associated electronics, as well as the couplant to a structure, from experimental data is presented. The investigation reveals that it is unnecessary for the instrumentation to have an ideal frequency response function for a transducer because imperfect measurement behaviour can be removed with post processing. A computer simulation of a homogeneous, isotropic pipe’s radial displacement is shown to agree closely with a corresponding measurement if a reasonably accurate frequency response function of the measurement chain is incorporated. A procedure to extract the cut-off frequencies of an unblemished pipe and the singularity frequencies of a notched pipe is developed. Frequency differences between the cut-off frequencies and the nearest frequencies of singularities introduced by a circumferential notch are investigated. It is confirmed experimentally that singularities are introduced by a notch and differences are measurable at a 95% confidence level.
3

ULTRASONIC SIMULATION AND MEASUREMENTS WITH CUT-OFF FREQUENCY EXTRACTIONS

ADEOGUN, KAZEEM 04 January 2013 (has links)
The removal of the effect of imperfect dynamic properties of ultrasonic transducers and associated electronics, as well as the couplant to a structure, from experimental data is presented. The investigation reveals that it is unnecessary for the instrumentation to have an ideal frequency response function for a transducer because imperfect measurement behaviour can be removed with post processing. A computer simulation of a homogeneous, isotropic pipe’s radial displacement is shown to agree closely with a corresponding measurement if a reasonably accurate frequency response function of the measurement chain is incorporated. A procedure to extract the cut-off frequencies of an unblemished pipe and the singularity frequencies of a notched pipe is developed. Frequency differences between the cut-off frequencies and the nearest frequencies of singularities introduced by a circumferential notch are investigated. It is confirmed experimentally that singularities are introduced by a notch and differences are measurable at a 95% confidence level.
4

Non destructive evaluation of thermal barrier coatings

Crutzen, Hugues P. S. January 2000 (has links)
No description available.
5

Modelling and design of 1-3 piezoelectric composite transducers

Hayward, Gordon January 2001 (has links)
No description available.
6

Cochlear Luere

Segergren, Magnus, Ogenvall, Lukas January 2008 (has links)
<p>The goal of this project was to together with Cochlear Bone Anchored Solutions AB develop a new cleaning tool for their Baha‐systems. Cochlear BAS AB is a daughter company to Cochlear Limited based in Sydney, Australia. Cochlear BAS AB is situated in Gothenburg and with its 150 employees develop and manufacture the Baha‐system. Baha is a bone anchored hearing aid which involves a minor surgery placing a titan implant, or abutment in the skull bone behind the client’s ear. By placing a sound processor which converts sound into vibrations on the abutment which then acts as a pathway for the vibrations to reach the skull and finally the cochlea giving clients improved hearing. Due to the fact that the skin never really fuses with the abutment daily cleaning is required of and two centimeters around the abutment. Today Cochlear BAS AB offers its clients a toothbrush with extra soft tip as cleaning tool. The goal is to cover today’s cleaning need with a, for the market, new product which fulfills all requirements set on the product by Cochlear BAS AB.</p><p>The group started by gathering lots of information of and about the Baha‐system as well as different types of cleaning methods used today. Creative methods were used to generate ideas on solving the problem. Four different concepts where put together based on all the information gathered, they were:</p><p>1. Brush – A reengineering of today’s cleaning tool.</p><p>2. Spray – Clean the abutment with a spray in an enclosed system.</p><p>3. Ultrasonic cleaning – Also called the electronic brush.</p><p>4. Topz – An easy to use and hygienic alternative.</p><p>These concepts were then presented to the company where they were evaluated together with the group and a decision was made to continue with the ultrasonic cleaning concept. The decision was followed by another information‐ and idea generating phase and the hunt for components was started. The piezo ceramics, the component creating the vibrations, was proven very difficult to find but the group were finally able to place an order of 3 pieces at a Japanese company through a contact in Sweden. Together with a teacher in electronics from school the other necessary components for the prototype were identified and ordered from ELFA.</p><p>This concept offers a cleaning tool which cleans efficiently and gently with ultrasonic technology in a compact en easy to use package. Ultrasonic cleaning is effective since it reaches in all nooks and crannies but is mild at the same time, it could even help heal the skin around the abutment. The product has a round shape and an attractive exterior with simple and smart functions built into it.</p><p>On and off with the entire top of the product which doubles as a button. The cleaning process itself could be as follows: The easy-to-use device is filled with gel or another medium in cup on the bottom of the product, the cup is then placed over the abutment and you start the device and let it run for about 30 seconds. After it’s done you remove the cleaning device and you rinse or towel the area around the abutment dry. All the dirt is flushed away with the gel and the abutment and the area around it is left clean.</p>
7

Mechanics and mechanisms of ultrasonic metal welding

De Vries, Edgar, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xix, 253 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Karl Graff, Dept. of Industrial, Welding and Systems Engineering. Includes bibliographical references (p. 223-230).
8

Cochlear Luere

Segergren, Magnus, Ogenvall, Lukas January 2008 (has links)
The goal of this project was to together with Cochlear Bone Anchored Solutions AB develop a new cleaning tool for their Baha‐systems. Cochlear BAS AB is a daughter company to Cochlear Limited based in Sydney, Australia. Cochlear BAS AB is situated in Gothenburg and with its 150 employees develop and manufacture the Baha‐system. Baha is a bone anchored hearing aid which involves a minor surgery placing a titan implant, or abutment in the skull bone behind the client’s ear. By placing a sound processor which converts sound into vibrations on the abutment which then acts as a pathway for the vibrations to reach the skull and finally the cochlea giving clients improved hearing. Due to the fact that the skin never really fuses with the abutment daily cleaning is required of and two centimeters around the abutment. Today Cochlear BAS AB offers its clients a toothbrush with extra soft tip as cleaning tool. The goal is to cover today’s cleaning need with a, for the market, new product which fulfills all requirements set on the product by Cochlear BAS AB. The group started by gathering lots of information of and about the Baha‐system as well as different types of cleaning methods used today. Creative methods were used to generate ideas on solving the problem. Four different concepts where put together based on all the information gathered, they were: 1. Brush – A reengineering of today’s cleaning tool. 2. Spray – Clean the abutment with a spray in an enclosed system. 3. Ultrasonic cleaning – Also called the electronic brush. 4. Topz – An easy to use and hygienic alternative. These concepts were then presented to the company where they were evaluated together with the group and a decision was made to continue with the ultrasonic cleaning concept. The decision was followed by another information‐ and idea generating phase and the hunt for components was started. The piezo ceramics, the component creating the vibrations, was proven very difficult to find but the group were finally able to place an order of 3 pieces at a Japanese company through a contact in Sweden. Together with a teacher in electronics from school the other necessary components for the prototype were identified and ordered from ELFA. This concept offers a cleaning tool which cleans efficiently and gently with ultrasonic technology in a compact en easy to use package. Ultrasonic cleaning is effective since it reaches in all nooks and crannies but is mild at the same time, it could even help heal the skin around the abutment. The product has a round shape and an attractive exterior with simple and smart functions built into it. On and off with the entire top of the product which doubles as a button. The cleaning process itself could be as follows: The easy-to-use device is filled with gel or another medium in cup on the bottom of the product, the cup is then placed over the abutment and you start the device and let it run for about 30 seconds. After it’s done you remove the cleaning device and you rinse or towel the area around the abutment dry. All the dirt is flushed away with the gel and the abutment and the area around it is left clean.
9

Ultrasonic cleaning of latex particle fouled membranes

Lamminen, Mikko Olavi, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Document formatted into pages; contains xvi, 111 p. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2005 Dec. 20.
10

A three dimensional model for generating the texture in B-scan ultrasound images

Goodsitt, Mitchell M. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 226-230).

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