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Objective waveform detection in electric response audiometryMason, S. M. January 1985 (has links)
No description available.
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Electronic Audience Response System in the secondary mathematics classroom to engage studentsBradley, Wendy Lara January 2015 (has links)
There is a current push for students to reach higher levels of achievement in mathematics in order to compete in today’s technologically changing world—a push that is being led by the Common Core Standards Initiative (CCSI) and the National Council of Teachers of Mathematics (NCTM). The issue with this new push, however, is that most students are disinterested in mathematics, resulting in them choosing to not participate in class. Active participation is a form of behavioral engagement that can lead to cognitive engagement and higher achievement. To improve participation, the expectancy-value theory suggests that the perceived benefit of participation needs to be increased while the cost reduced. Electronic audience response systems (EARS) have the potential to accomplish this, and they have begun to be implemented at the college level with primarily positive results. The purpose of this study is to examine if EARS can similarly improve student participation and achievement in the secondary geometry classroom. Using a quasi- experimental design, this study compared students’ participation using hand raising versus EARS devices in the classroom and found that student participation increased significantly when using EARS. To look at achievement, a treatment and comparison group design was used, and despite that no statistically significant difference was found, the results do support EARS’ potential to improve achievement. Lastly, this study looked at student and teacher perceptions of using the EARS in the classroom, and found mixed results. / Math & Science Education
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Measurement of Occupational Sound Exposure from Communication HeadsetsNassrallah, Flora G. January 2016 (has links)
Increased use of communication headsets found in various workplaces raises concerns regarding exposure to potentially hazardous noise levels. Current national and international standards specify a wide range of simple and specialized methods for the measurement of sound exposure under communication headsets. However, to date, quantitative data comparing the degree of agreement between the different measurement methods or their relative performance are lacking, and it is not known if occupational health and safety (OHS) or hearing loss prevention (HLP) stakeholders have the necessary training and equipment to integrate them in their daily practice.
A three-step study addressing several knowledge gaps on this topic is presented in this thesis. First, a questionnaire survey distributed to OHS and HLP stakeholders has revealed that knowledge of specialized measurement techniques and access to the necessary equipment varies significantly depending on the training of the different professionals. There is therefore reason to specify several methods in measurement standards to meet the specific needs and expertise of the different stakeholders involved. Second, a series of experiments conducted with single and multiple expert participants indicated that the Type 1 artificial ear is not suited for sound exposure measurement with communication headsets, while Type 2 and Type 3.3 artificial ears are in good agreement with the acoustic manikin technique specified in the International standard ISO 11904-2. Finally, laboratory experiments were conducted to test the indirect calculation method proposed in the Canadian standard CSA Z107.56. Results revealed that the calculation method is suitable to identify possible situations of exposure over the regulatory limit (e.g. 85 dBA), but refinements are proposed to improve measurement accuracy.
Overall, this thesis provides new knowledge to guide selection of the most suitable methods for the assessment of communication headset exposure taking into account expertise, access to equipment, and field logistic constraints. Results also have direct implications for future revisions of existing measurement standards. Finally, this work could be the basis for detailed guidelines on noise exposure measurements under communication headsets to better inform OHS and HLP professionals and ultimately prevent occupational noise-induced hearing loss.
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The Mass-Personal Divide: Bridging Scholarship and Paving Ground Through the Lens of Environmental Discourse on Public Land UseSeroka, Laura A. 19 November 2019 (has links)
No description available.
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Enabling Test Automation for Industrial PLC ProgramsSalari, Mikael Ebrahimi January 2024 (has links)
Testing safety-critical systems, particularly those controlled by Programmable Logic Controllers (PLC), is crucial for ensuring the safe and reliable operation of industrial processes. This thesis addresses the critical need for automated testing of safety-critical PLC systems used in various industrial settings. Despite the significance of testing, current practices rely heavily on manual methods, leading to challenges in scalability and reliability. This work investigates enabling test automation for PLCs to facilitate and assist the current manual testing procedures in the industry. The thesis proposes and evaluates test automation techniques and tools tailored to PLCs, focusing on Function Block Diagram and Structured Text languages commonly used in industry. We systematically compare test automation tools for PLC programs, after which we propose a PLC to Python translation framework called PyLC to facilitate automated test generation. The experiment employing the EARS requirement engineering pattern reveals that while engineers use semi-formal notations in varied ways to create requirements, leading to completeness issues, it confirms the viability of employing EARS requirements for PLC system testing. Subsequently, the proposed automation approaches are fully implemented and evaluated using real-world PLC case studies, comparing their efficiency against manual testing procedures. The findings highlight the feasibility and benefits of automating PLC testing, offering insights into improving development and testing processes through carefully selected automation tools for the CODESYS IDE, a well-known PLC development environment. Additionally, we show that leveraging Python-based automated testing techniques and mutation analysis enhances testing effectiveness. Furthermore, incorporating best practices in requirement engineering, as demonstrated by the EARS approach, contributes to further enhancing testing efficiency and effectiveness in PLC development. / VeriDevOps, SmartDelta
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On Development and Performance Evaluation of Some Biosurveillance MethodsZheng, Hongzhang 09 August 2011 (has links)
This study examines three applications of control charts used for monitoring syndromic data with different characteristics. The first part develops a seasonal autoregressive integrated moving average (SARIMA) based surveillance chart, and compares it with the CDC Early Aberration Reporting System (EARS) W2c method using both authentic and simulated data. After successfully removing the long-term trend and the seasonality involved in syndromic data, the performance of the SARIMA approach is shown to be better than the performance of the EARS method in terms of two key surveillance characteristics, the false alarm rate and the average time to detect the outbreaks.
In the second part, we propose a generalized likelihood ratio (GLR) control chart to detect a wide range of shifts in the mean of Poisson distributed biosurveillance data. The application of a sign function on the original GLR chart statistics leads to downward-sided, upward-sided, and two-sided GLR chart statistics in an unified framework. To facilitate the use of such charts in practice, we provide detailed guidance on developing and implementing the GLR chart. Under the steady-state framework, this study indicates that the overall GLR chart performance in detecting a range of shifts of interest is superior to the performance of traditional control charts including the EARS method, Shewhart charts, EWMA charts, and CUSUM charts.
There is often an excessive number of zeros involved in health care related data. Zero-inflated Poisson (ZIP) models are more appropriate than Poisson models to describe such data. The last part of the dissertation considers the GLR chart for ZIP data under a research framework similar to the second part. Because small sample sizes may influence the estimation of ZIP parameters, the efficiency of MLEs is investigated in depth, followed by suggestions for improvement. Numerical approaches to solving for the MLEs are discussed as well. Statistics for a set of GLR charts are derived, followed by modifications changing them from two-sided statistics to one-sided statistics. Although not a complete study of GLR charts for ZIP processes, due to limited time and resources, suggestions for future work are proposed at the end of this dissertation. / Ph. D.
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Molecular Regulators of Innervation and Patterning in the Developing Chicken Inner EarMary K. Scott (5930246) 17 January 2019 (has links)
<p>Normal hearing and balance relies on the detection of sound, orientation and acceleration by sensory hair cells (HCs) located in the inner ear. Once sound is detected, that information must be transmitted to the brain by sensory neurons. Damage to the HCs and/or neurons in the auditory or vestibular organs of the inner ear can result in hearing loss or balance disorders. In mammals, these disorders can be permanent, as HCs do not regenerate after damage. While hearing aids and cochlear implants can restore some ability to hear, there are currently no molecular therapies for hearing loss. By examining genes involved in HC development and innervation, basic science can identify candidate genes for potential molecular therapies. This dissertation focuses on molecular regulators involved in establishing and/or maintaining innervation in the chicken inner ear during embryonic development.</p><p>The basilar papilla (BP) is the auditory sensory organ in the chicken and is homologous to the mammalian organ of Corti (oC). The BP houses two types of sensory HCs – tall HCs and short HCs. On the neural side of the BP, tall HC receive primarily afferent innervation (neural-side identity). On the abneural side, short HC receive primarily efferent innervation (abneural-side identity). The patterning of these two identities along the radial axis is dependent upon the precise spatiotemporal expression of certain genes during embryonic development. One such gene is <i>Wingless/integrated (Wnt)9a</i>.</p><p>Previous work has shown that <i>Wnt9a</i>is expressed on the neural edge of the BP and is likely secreted in a gradient across the prosensory domain during crucial time points when proliferation, differentiation, and innervation are occurring. When <i>Wnt9a </i>was overexpressed, we observed an increase in the width of the BP as well as an expansion of the neural-side identity, likely at the expense of the abneural-side identity. RNA sequencing of <i>Wnt9a</i>-overexpressing and control BPs identified genes involved in the Wnt signaling pathway, cytoskeletal remodeling, and axon guidance signaling that were differentially expressed. This dissertation focuses on axon guidance genes, specifically those involved in Slit/Robo (Roundabout), Contactin (Cntn), and Semaphorin (Sema) signaling, that were differentially expressed in this RNA sequencing data set.</p><p>Slits typically act as repulsive cues for neurites expressing Robo receptors. RNA sequencing data indicates that <i>Slit2</i>transcripts increased by 1.2 fold when <i>Wnt9a </i>was overexpressed. When examining Slit2 spatial expression pattern in <i>Wnt9a-</i>overexpressing BPs, we did not observe an upregulation of <i>Slit2 </i>but rather an expansion of the <i>Slit2</i>-expression domain that is likely due to increased proliferation in response to <i>Wnt9a</i>. To better understand the role of Slit/Robo signaling in the developing BP, we examined the radial expression patterns of <i>Slit2</i>, <i>Robo1</i>, and <i>Robo2</i>. <i>Slit2 </i>is expressed on the anterior and posterior walls of the cochlear duct (CD). <i>Robo1</i>and <i>Robo2 </i>had graded expression in the prosensory domain of the BP, highest on the abneural side. <i>Robo1</i>is also present in the auditory ganglion. While only a small population of cochleovestibular ganglion neurites have been previously shown to respond to Slits, Slit-Robo has also been shown to activate TCF transcription factor by non-canonically activating β-catenin through Abl kinase. We examined Abl kinase-activated b-catenin in <i>Slit2-</i>and <i>Wnt9a-</i>overexpressing BPs but did not observe a change in phosphorylated b-catenin. We also overexpressed a dominant-negative Robo1. In some dominant-negative Robo1 overexpressing ears, we observed a reduction in ganglion size; however, this affect did not reliably replicate. These data suggests that Slit-Robo signaling could be involved in neuroblast delamination and/or migration.</p><p>RNA sequencing results indicate that <i>Contactin 6</i><i>Cntn6 </i>transcripts increased by 1.5 fold when <i>Wnt9a </i>was overexpressed. Contactins are cell adhesion molecules that have been previously shown to impact neurite outgrowth and innervation. In the auditory field, clinical studies have also shown that patients diagnosed with autism who also have mutations in <i>Cntn5 </i>and <i>Cntn6 </i>are more likely to exhibit increased sensitivity to sound. Based on RNA sequencing in the embryonic day (E)6 chicken ear, <i>Cntn6 </i>has low levels of expression in controls. We attempted to examine the spatial expression of <i>Cntn6 </i>but found that <i>in situ </i>hybridization is not sensitive enough to detect low levels of <i>Cntn6 </i>in control or <i>Wnt9a-</i>overexpressing BPs.</p><p>Class III Semaphorinsecreted ligands are known to repel neurites expressing Neuropilin (Nrp) and/or Plexin (Plxn) receptors. <i>Sema3D </i>and <i>Nrp2 </i>were downregulated in the presence of exogenous <i>Wnt9a</i>; however, the spatial expression of these transcripts did<i></i>not support their role in establishing or maintaining radial innervation patterns. There is, however, a growing body of literature supporting that Sema signaling also has alternative roles in development such as synaptogenesis, boundary formation, and vasculogenesis. To evaluate these options during inner ear development, we used <i>in situ </i>hybridization or immunohistochemistry to map the expression of <i>Sema3D</i>, <i>Sema3F</i>, Nrp1<i>, Nrp2</i>, and <i>PlxnA1 </i>in the chicken inner ear from E5 to E10. The resulting expression patterns in either the otic epithelium or its surrounding mesenchyme suggest that Sema signaling could be involved in each of the varied functions reported for other tissues. <i>Sema3D</i>expression flanking the sensory tissue in vestibular organs suggests that it may repel <i>Nrp2</i>- and <i>PlxnA1</i>-expressing neurites of the vestibular ganglion away from nonsensory epithelia, thus channeling them into the sensory domains at E5-E8. Expression of Sema signaling genes in the sensory hair cells of both the auditory and vestibular organs on E8–E10 may implicate Sema signaling in synaptogenesis. In the nonsensory regions of the cochlea, <i>Sema3D</i>in the future tegmentum vasculosum opposes Nrp1 and <i>PlxnA1 </i>in the future cuboidal cells; the abutment of ligand and receptors in adjacent domains may enforce or maintain the boundary between them. In the mesenchyme, Nrp1 colocalized with capillary-rich tissue. <i>Sema3D </i>immediately flanks this Nrp1-expressing tissue, suggesting a role in endothelial cell migration towards the inner ear. In summary, Sema signaling may play multiple roles in the developing inner ear.</p><p>To better understand innervation patterns in the avian BP, we also examined the developing efferent innervation patterns from E11 to E17 using NeuroVue lipophilic tracer dye. Our data suggest that efferents have already begun to penetrate the sensory epithelium at E11 and that efferents arrive to the ipsilateral BP earlier than the contralateral BP. By E12, many efferents appear to send back branches out to short HCs. At E15, many efferents appear to have reached the abneural edge of the BP, are innervating the hyaline cells, and are projecting apically.</p><p>In summary, this work suggests that Slit and Sema signaling are not involved in establishing radial innervation patterns but may have alternative roles in inner ear development. Additionally, while efferents appear to arrive to the ipsilateral BP sooner than the contralateral BP, both ears send projections across the radial axis and back branch around the same time.</p>
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Why only two ears? Some indicators from the study of source separation using two sensorsJoseph, Joby 08 1900 (has links)
In this thesis we develop algorithms for estimating broadband source signals from a mixture using only two sensors. This is motivated by what is known in the literature as cocktail party effect, the ability of human beings to listen to the desired source from a mixture of sources with at most two ears. Such a study lets us, achieve a better understanding of the auditory pathway in the brain and confirmation of the results from physiology and psychoacoustics, have a clue to search for an equivalent structure in the brain which corresponds to the modification which improves the algorithm, come up with a benchmark system to automate the evaluation of the systems like 'surround sound', perform speech recognition in noisy environments. Moreover, it is possible that, what we learn about the replication of the functional units in the brain may help us in replacing those using signal processing units for patients suffering due to the defects in these units.
There are two parts to the thesis. In the first part we assume the source signals to be broadband and having strong spectral overlap. Channel is assumed to have a few strong multipaths. We propose an algorithm to estimate all the strong multi-paths from each source to the sensors for more than two sources with measurement from two sensors. Because the channel matrix is not invertible when the number of sources is more than the number of sensors, we make use of the estimates of the multi-path delays for each source to improve the SIR of the sources. In the second part we look at a specific scenario of colored signals and channel being one with a prominent direct path. Speech signals as the sources in a weakly reverberant room and a pair of microphones as the sensors satisfy these conditions. We consider the case with and without a head like structure between the microphones. The head like structure we used was a cubical block of wood. We propose an algorithm for separating sources under such a scenario. We identify the features of speech and the channel which makes it possible for the human auditory system to solve the cocktail party problem. These properties are the same as that satisfied by our model. The algorithm works well in a partly acoustically treated room, (with three persons speaking and two microphones and data acquired using standard PC setup) and not so well in a heavily reverberant scenario.
We see that there are similarities in the processing steps involved in the algorithm and what we know of the way our auditory system works, especially so in the regions before the auditory cortex in the auditory pathway. Based on the above experiments we give reasons to support the hypothesis about why all the known organisms need to have only two ears and not more but may have more than two eyes to their advantage. Our results also indicate that part of pitch estimation for individual sources might be occurring in the brain after separating the individual source components. This might solve the dilemma of having to do multi-pitch estimation. Recent works suggest that there are parallel pathways in the brain up to the primary auditory cortex which deal with temporal cue based processing and spatial cue based processing. Our model seem to mimic the pathway which makes use of the spatial cues.
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Using Ears for Human IdentificationSaleh, Mohamed Ibrahim 18 July 2007 (has links)
Biometrics includes the study of automatic methods for distinguishing human beings based on physical or behavioral traits. The problem of finding good biometric features and recognition methods has been researched extensively in recent years. Our research considers the use of ears as a biometric for human recognition. Researchers have not considered this biometric as much as others, which include fingerprints, irises, and faces. This thesis presents a novel approach to recognize individuals based on their outer ear images through spatial segmentation. This approach to recognizing is also good for dealing with occlusions. The study will present several feature extraction techniques based on spatial segmentation of the ear image. The study will also present a method for classifier fusion. Principal components analysis (PCA) is used in this research for feature extraction and dimensionality reduction. For classification, nearest neighbor classifiers are used. The research also investigates the use of ear images as a supplement to face images in a multimodal biometric system. Our base eigen-ear experiment results in an 84% rank one recognition rate, and the segmentation method yielded improvements up to 94%. Face recognition by itself, using the same approach, gave a 63% rank one recognition rate, but when complimented with ear images in a multimodal system improved to 94% rank one recognition rate. / Master of Science
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Green communication: případová studie na outdoorové oděvní firmě Patagonia Inc. / Green communication: case study of the outdoor clothing company Patagonia Inc.Krchová, Eva January 2019 (has links)
Tato diplomová práce, Byla, nebyla jedna firma, a ta se jmenovala Patagonie, se zabývá případovou studií outdorové značky Patagonia a jejích aktivistických transmediálních obsahových projektů, s důrazem na nejaktuálnější kampaň značky: Zachraňte Bears Ears. Park Bears Ears je obdobou české chráněné krajinné oblasti, jejíž status ale současný americký prezident Donald Trump nedávno neautorizovaně sebral. Zatímco se firma zabývá výrobou a prodejem kvalitního outdoorového oblečení, tak se Patagonie ve stejnou dobu také aktivně angažuje do veřejného dění. Firma informuje své zákazníky zejména o stavu životního prostředí prostřednictvím svćyh multimediálních poutavých příběhů nesoucí prvky žurnalistiky. Patagonie usiluje o podněcování veřejnosti a ostatních firem zapojovat se do občanské společnosti, změnit spotřební chování nejen zákazníků, ale i výrobců, s konec̆ným cílem udržitelné ochrany této křehké planety, kterou my všichni obýváme. Patagonie potvrzuje své altruistické odhodlání prostřednictvím svého oficiálního firemního hesla: "Jsme v businessu, abychom zachránili planetu."
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