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A methodology for tracking the scapulaunder dynamic conditionsDurazo Romero, Emmanuel Santiago January 2016 (has links)
In the diagnosis and analysis of shoulder instability a precise determination of the location and orientation of the Glenohumeral joint is important. A better understanding of shoulder kinematics and kinetics will help clinicians and therapists in the diagnosis and treatment of shoulder pathologies. To-date, non-invasive skin-based methods are often either restricted to quasi-static measurements or are inaccurate during dynamic assessments at high humeral elevations as a result of soft skin artefact. Tracking the orientation of the scapula is difficult because it is surrounded by soft tissues, is held mainly by muscles and has only one direct point of attachment to the thorax. Instability of the glenohumeral joint generates poor functionality of the shoulder labrum and capsule as well as in the muscle and connective tissue structures that surround the shoulder. As the clinical phenomenon of shoulder instability is extremely complex, one of the priorities for the specialist in avoiding a faulty diagnosis is to recognise, identify and classify shoulder pathologies such as muscle patterning instability in the early stages of the investigation. A two stage methodology for non-invasive tracking of the scapula under dynamic conditions is presented in this work. The methodology provides scapula location by combining data from two surface mounted sensors using a regression-type equation formulated from quasi-static trials undertaken using a scapula locator and three IMUs (first stage). In the second stage, the least square fit is used to improve the scapular orientation by utilising data from only two IMUs (humerus and scapula) under dynamic conditions. Accuracy was assessed in an animal study by comparing results with those from a bone based method during quasi static and dynamic tests. Tests were also undertaken to investigate the errors induced by the soft tissue artefact in surface based scapula location measurement. In dynamic trials the methodology proved more accurate in determining scapula location than a standard skin-based approach, and showed that the greatest contribution to soft tissue artefact was from the epidermal, dermal and subcutaneous tissue layers as opposed to the muscle layer. We confirmed that, in cases where subjects have relatively small amounts of soft tissue surrounding the scapula, surface based methods could provide reasonable accuracy. Our methodology utilised subject-specific data to formulate a regression equation, and can be used to provide accurate, non-invasive tracking of the scapula under dynamic conditions in subjects regardless of individual body morphology. After the methodology validation, study tests were undertaken in a case study in order to estimate the scapula orientation under dynamic conditions in a human without symptoms of any shoulder pathologies and in one participant diagnosed with shoulder instability due to muscle patterning. The two stage methodology is proven to work in a healthy human participant in dynamic tests, in a person with no suspicion of shoulder instability. This methodology allows the error reduction generated by the soft tissues surrounded the scapula. The work presented here can be used as a framework for developing diagnosis protocols by using modern technology.
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Real-Time Interrogation of Optical Sensors Based on Wavelength-to-Time MappingDeng, Hong January 2018 (has links)
Theoretical and experimental studies of real-time interrogation of optical sensors based on wavelength-to-time (WTT) mapping are presented. The sensing information is encoded in the spectrum of an optical sensor, and transferred to the time domain by using WTT mapping. Utilizing digital electronics for post processing, the sensing information can be interrogated at an ultra-high speed and resolution. Two sensors based on WTT mapping are proposed and demonstrated.
First, a random grating sensor for simultaneous measurement of the temperature and strain is investigated. An ultra-short pulse from a mode-lock laser is spectrum shaped by a high-birefringence random grating to generate two orthogonally polarized spectrums, which are then fed to an optical loop in which a linearly chirped fiber Bragg grating is incorporated. Linear WTT mapping is implemented, and two temporally separated optical pulses are generated, and then converted to two electrical waveforms at a photodetector. Pulse compression is then employed. By measuring the temporal intervals of the temporally compressed pulses, the strain and temperature information can be retrieved.
Conventional fiber based sensors are not sensitive to the refractive index change of the environment. In the second sensor, a silicon photonic microdisk resonator (MDR) for temperature and liquid refractive index sensing is proposed and demonstrated. By using the notches in the spectrum of the MDR, a microwave photonic filter (MPF) is implemented. By feeding a linearly chirped microwave signal to the MPF, a filtered signal with its temporal location representing the spectrum is generated. By monitoring the time location of the filtered signal, the temperature or the refractive index information is revealed.
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Optical detection system for ultrasonic surface displacementsGodfrey, Martin William January 1986 (has links)
The work was carried out with the aim of developing an optical interferometric detection system. This was to be applied to the quantative measurement of low amplitude, high frequency surface displacements (< 1nm at several MHz). Two forms of interferometric detector are investigated. The performance and limitations in particular measurement situations are assessed for both types of interferometer. The first type of detector investigated is a miniature stabilised interferometer. The design of a stabilisation system is given, along with ways in which it can be optimised for a particular environment. The second type of detector studied is a quadrature interferometer. Various methods of processing the two channels of information from this device are discussed. The design of a new method of processing the signals is given, and its performance determined. The interferometric sensor is combined with a waveform digitiser and microcomputer to form an integrated detection system. Analysis of the waveforms obtained is performed by a system of Pascal programs developed for this purpose. The detection system is applied to tasks such as the calibration of other forms of transducer and the characterisation of artificial sources of acoustic emission. The results of experimental studies are given and the applications of such a system discussed.
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Polysilicon flow sensors for integration with microfluidic systemsZhao, Hao January 2003 (has links)
No description available.
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Using motes for high resolution hydrological measurementTrubilowicz, Joel William 05 1900 (has links)
Low cost, low power wireless sensors (motes) promise to revolutionize environmental data collection, but are they currently refined enough for widespread use by hydrologists? Their viability as a replacement for traditional data collection techniques was investigated in a 7 ha forested watershed in south-western British Columbia. The watershed included 41 instrument clusters measuring air and soil temperature, humidity, throughfall, soil moisture content, overland flow and groundwater head. The foundation of each cluster was a data box containing a MDA300 data acquisition board and a MICA2 processor board from Crossbow Technologies, Inc.™ that allowed for short range wireless data collection. The 41 motes each recorded data every 15 minutes from July, 2006, to April, 2007. In addition to reporting on the reliability of the motes and sensors during the 10 months deployment, the high spatial and temporal resolution data collected by this study gave the opportunity for many analyses of catchment processes. As soil moisture and throughfall are two influential processes in the exchange of water between the earth and the atmosphere, these were the focus of the data analysis. The first analysis was a resampling experiment on seven different events selected from the full data set. Comparing 100 different subsamples each of 5, 10 and 20 points for throughfall and soil moisture showed if increasing the sample size eventually produced diminishing returns in the ability to reproduce the true catchment mean. With significant differences in prediction ability for both soil moisture and throughfall at times of differing hydrologic activity, this analysis provides further support for the theories of changing moisture states of soil moisture and threshold values for throughfall. The second analysis described how the organization of soil moisture and throughfall changed during a range of weather conditions and timescales. Spatial representation of normalized values and Pearson correlation coefficients showed that there were distinct differences between wet and dry periods for soil moisture and between long and short analysis periods for throughfall. / Forestry, Faculty of / Graduate
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Electromagnetic modelling of superconducting sensor designsGerra, Guido January 2003 (has links)
The problem of design optimisation of thin film direct current Superconducting QUantum Interference Device (SQUID) magnetometers made of YBCO (YBa2Cu3O7-x) was considered. The inductances and effective areas were calculated using the software package 3D-MLSI. Resolution and reliability issues were first tested on simple superconducting systems, showing good agreement with analytical formulae and experimental results, and demonstrating that a remarkable precision can be obtained though at the expense of CPU time and memory. The software was then used to simulate a SQUID magnetometer fabricated in the Device Materials Group of the Department of Materials Science and Metallurgy, proving that 3D-MLSI can be used to predict the parameters of real systems with acceptable accuracy.
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Analysis and modelling of light-scattering sensors using artificial neural networksNaimimohasses, Rambod January 1996 (has links)
There have been few theoretical advancements in the theory of light-scattering from particles since the days of Rayleigh and of those who have come later in the early twentieth century such as Mie, Lorenz and Born. The lack of progressive advancements in this area is a clear indication of the difficulties faced. However, the advancement of optical sensor technology and computer systems, representing thus an empirical advancement, have managed to produce effective means for collecting large amounts of high quality data in a relatively short time. Such difference in advancement between these two approaches signifies the necessity for establishing generic approximations and tools that can be used effectively in both domains.
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Connected Mobile Sensors for Self-DeploymentWang, Xueqian January 2015 (has links)
A Mobile Sensor Networks (MSNs) is normally made up of a number of mobile sensors which can be placed in a region of interest (ROI) by people. Sensors communicate with each other through wireless links to perform the distributed sensing ability for covering a region. Through a specific algorithm, the sensors move automatically, and finally the sensor network achieves a large sensing coverage. Sensing coverage can be established and promoted by different algorithms, and a good algorithm can lead sensors to form the largest possible sensing area without any sensing holes (areas that cannot be detected or monitored). The coverage of a sensor network is defined as the total area of interest covered, minus the area of the sensing holes.
We introduce a novel
algorithm called the Spanning Tree-based Greedy-Rotation-Back (STGRB). The
traditional Greedy-Rotation-Greedy (GRG) algorithm uses a point as a specific start
so it's not appropriate for practical circumstances. So in the STGRB,
we first use a spanning tree algorithm to get the gravity center (the sensor
that connects the most sensors or is physically close to most of the other sensors) of the network. In this way we eliminate the first condition of selecting a sensor as a start point and also we conserve the energy of the sensors via letting them move a shorter distance.
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2D AND 3D SHAPE VARIATION AMONG ELASMOBRANCH OLFACTORY ROSETTESUnknown Date (has links)
The functional impacts of olfactory rosette variation in elasmobranchs is unresolved. Our goal was to quantify rosette morphology and shape from 14 species using dissections, phylogenetic comparisons, and microCT imaging. We hypothesized that lamellar count and rosette shape (fineness ratio) would not scale with animal size, but internal rosette size variables must scale positively. We found that fineness ratio and lamellar counts varied significantly among species, and were positively correlated. The first two principal components of the pPCA explained 82% of the variation, with fineness ratio and lamellar count contributing the most. There were no significant differences between rosette structure or volume when comparing dissected values to in situ values obtained using diceCT. Based on our results, we hypothesize that variations in rosette shape and morphology will impact hydrodynamics and optimize odorant detection, and these data can be used to create 3D models for future hydrodynamic studies. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
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Development and Testing of Gold(I) and Europium(III) Based Sensors for Environmental ApplicationsBenton, Erin Nicole 05 1900 (has links)
This dissertation focuses on the development, characterization, and analysis of luminescent materials and coatings for sensing applications, including CO2, heavy metals, and silver. Chapter 2 involves the use of a gold(I) pyrazolate trimer that is able to detect silver ions with an AgNP medium. Detection of silver is vital, because there is an influx of silver into our environment caused by the increased use of AgNP. Therefore, having a sensor that is able to differentiate between and detect only Ag ions is an important first step to solving the toxicity mystery of AgNPs. Chapter 3 focuses on the development of sensor coatings containing a Eu(III) based luminescent system for sensing dissolved CO2 without the aid of an absorption-based dye. It is well-known that monitoring CO2 levels in our environment is important since even at low concentrations it can cause adverse health effects to the human body. This work demonstrates a pH-sensitive Eu complex being used directly as a CO2 sensor without the aid of any other absorption-based dye. Chapter 4 explores the idea of developing a heavy metal sensor for lead and its ability to detect lead in wide concentration range upon changing the pH of the medium and the polymer matrix. Different heavy metals have toxicity at different concentrations, therefore, being able to change the dynamic range of the sensor is advantageous. This research is the first step towards developing a luminescent Pb sensor with a tunable dynamic range.
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