Fifteen nonsmoking and fifteen smoking females 19 to 36 years of age were evaluated on measures of signal-to-noise ratio (SNR), jitter, shimmer, and speaking fundamental frequency (F0). The results indicated that: 1) there is a significant difference between female smokers and nonsmokers on measures of SNR, mean, and maximum F0 and, 2) there is no significant difference between female smokers and nonsmokers on measures of jitter, shimmer and minimum F0 . The SNR was found to be a powerful tool which is capable of distinguishing subtle vocal characteristics between the subject groups. It would appear that cigarette smoking may have an impact on the voice before distinct laryngeal pathologies are present.

Background: In certain masking paradigms, the masker can have two components, energetic and informational. Energetic masking is the traditional peripheral masking, whereas informational masking involves confusions (uncertainty) between the signal and masker that originate more centrally in the auditory system. Sperry et al (1997) used Northwestern University Auditory Test No. 6 (NU-6) words in multitalker babble to study the differential effects of energetic and informational masking using babble played temporally forward (FB) and backward (BB). The FB and BB are the same except BB is void of the contextual and semantic content cues that are available in FB. It is these informational cues that are thought to fuel informational masking. Sperry et al found 15% better recognition performance (∼3 dB) on BB than on FB, which can be interpreted as the presence of informational masking in the FB condition and not in the BB condition (Dirks and Bower, 1969). The Words-in-Noise Test (WIN) (Wilson, 2003; Wilson and McArdle, 2007) uses NU-6 words as the signal and multitalker babble as the masker, which is a combination of stimuli that potentially could produce informational masking. The WIN presents 5 or 10 words at each of seven signal-to-noise ratios (S/N, SNR) from 24 to 0 dB in 4 dB decrements with the 50% correct point being the metric of interest. The same recordings of the NU-6 words and multitalker babble used by Sperry et al are used in the WIN. Purpose: To determine whether informational masking was involved with the WIN. Research Design: Descriptive, quasi-experimental designs were conducted in three experiments using FB and BB in various paradigms in which FB and BB varied from 4.3 sec concatenated segments to essentially continuous. Study Sample: Eighty young adults with normal hearing and 64 older adults with sensorineural hearing losses participated in a series of three experiments. Data Collection and Analysis: Experiment 1 compared performance on the normal WIN (FB) with performance on the WIN in which the babble segment with each word was reversed temporally (BB). Experiment 2 examined the effects of continuous FB and BB segments on WIN performance. Experiment 3 replicated the Sperry et al (1997) experiment at 4 and 0 dB S/N using NU-6 words in the FB and BB conditions. Results: Experiment 1-with the WIN paradigm, recognition performances on FB and BB were the same for listeners with normal hearing and listeners with hearing loss, except at the 0 dB S/N with the listeners with normal hearing at which performance was significantly better on BB than FB. Experiment 2-recognition performances on FB and BB were the same at all SNRs for listeners with normal hearing using a slightly modified WIN paradigm. Experiment 3-there was no difference in performances on the FB and BB conditions with either of the two SNRs. Conclusions: Informational masking was not involved in the WIN paradigm. The Sperry et al results were not replicated, which is thought to be related to the way in which the Sperry et al BB condition was produced.

This review presents a brief history of the evolution of speech audiometry from the 1800s to present day. The two-component aspect of hearing loss (audibility and distortion), which was formalized into a framework in past literature, is presented in the context of speech recognition. The differences between speech recognition in quiet and in background noise are discussed as they relate to listeners with normal hearing and listeners with hearing loss. A discussion of the use of sentence materials versus word materials for clinical use is included as is a discussion of the effects of presentation level on recognition performance in quiet and noise. Finally, the effects of age and hearing loss on speech recognition are considered.

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第21915号 / 情博第698号 / 新制||情||120(附属図書館) / 京都大学大学院情報学研究科数理工学専攻 / (主査)教授 梅野 健, 教授 山下 信雄, 教授 守倉 正博 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

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With the intention of improving process efficiency and product quality, Design of Experiments (DoE) is often applied in industry as a tool for engineers in planning experiments and product design. One of the methods in DoE is the Taguchi method that provides a practical procedure to design experiments with an appropriate number of tests for identifying optimal parametric settings of products. The purpose of this study is to investigate how Design of Experiments, specifically the Taguchi method, can be applied to analyze the performance of the lubricants used to stainless fasteners which are common products in various industries. The study has been implemented at the case company which manufactures stainless fasteners. Combining with qualitative and quantitative methods, this thesis work started from reviewing the previous research on DoE, the Taguchi method and various analysis tools as well as information on lubricants. Experiments were designed based on observations, interview, and literature collection. The actual tests were carried out on the case company's wax process where lubricants with different levels for the respective parameters were applied to screws and nuts. The fasteners were tested in a friction machine and UV lamp at the case company. The implemented experiments and data analysis have demonstrated which levels for each parameter of the lubricant resulted in the least friction. The parameters considered in the experiments are mixing ratio, number of dips and time in dips, which have varying degrees of influence on friction. The outcomes contribute to improved process efficiency and product quality within the steel industry and similar sectors. The visualization of the lubricant by UV lamp confirmed that the coating varied according to the levels of the parameters. The theoretical contribution can facilitate further research while the practical contribution provides an approach for experiments in quality improvement on lubricants. The thesis work has also identified the need for further research into the drying process after lubricant application and the use of UV lamp to improve control of lubricant smoothness.

Nonstationary signals are common in many environments such as radar, sonar, bioengineering and power systems. The nonstationary nature of the signals found in these environments means that classicalspectralanalysis techniques are notappropriate for estimating the parameters of these signals. Therefore it is important to develop techniques that can accommodate nonstationary signals. This thesis seeks to achieve this by firstly, modelling each component of the signal as having a polynomial phase and by secondly, developing techniques for estimating the parameters of these components. Several approaches can be used for estimating the parameters of polynomial phase signals, eachwithvarying degrees ofsuccess.Criteria to consider in potential estimation algorithms are (i) the signal-to-noise (SNR) ratio threshold of the algorithm, (ii) the amount of computation required for running the algorithm, and (iii) the closeness of the resulting estimates' mean-square errors to the minimum theoretical bound. These criteria will be used to compare the new techniques developed in this thesis with existing techniques. The literature on polynomial phase signal estimation highlights the recurring trade-off between the accuracy of the estimates and the amount of computation required. For example, the Maximum Likelihood (ML) method provides near-optimal estimates above threshold, but also incurs a heavy computational cost for higher order phase signals. On the other hand, multi-linear techniques such as the high-order ambiguity function (HAF) method require little computation, but have a significantly higher SNR threshold than the ML method. Of the existing techniques, the cubic phase (CP) function method is a promising technique because it provides an attractive SNR threshold and computational complexity trade-off. For this reason, the analysis techniques developed in this thesis will be derived from the CP function. A limitation of the CP function is its inability to accurately process phase orders greater than three. Therefore, the first novel contribution to this thesis develops a broadened class of discrete-time higher order phase (HP)functions to address this limitation.This broadened class is achieved by providing a multi-linear extension of the CP function. Monte Carlo simulations are performed to demonstrate the statistical advantage of the HP functions compared to the HAFs. A first order statistical analysis of the HP functions is presented. This analysis verifies the simulation results. The next novel contribution is a technique called the lower SNR cubic phase function (LCPF)method. It is an extension of the CP function, with the extension enabling performance at lower signal-to-noise ratios (SNRs). The improvement of the SNR threshold's performance is achieved by coherently integrating the CP function over a compact interval in the two-dimensional CP function space. The computation of the new algorithm is quite moderate, especially when compared to the ML method. Above threshold, the LCPF method's parameter estimates are asymptotically efficient. Monte Carlo simulation results are presented and a threshold analysis of the algorithm closely predicts the thresholds observed in these results. The next original contribution to this research involves extending the LCPF method so that it is able to process multicomponent cubic phase signals and higher order phase signals. The LCPF method is extended to higher orders by applying a windowing technique as opposed to adjusting the order of the kernel as implemented in the HP function method. To demonstrate the extension of the LCPF method for processing higher order phase signals and multicomponent cubic phase signals, some Monte Carlo simulations are presented. Finally, these estimation techniques are applied to real-worldscenarios in the fields of Power Systems Analysis, Neuroethology and Speech Analysis.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / This paper concentrates on aircraft specific issues and impacts of utilizing a "C" band telemetry system on a new or existing instrumentation system.

A criança com deficiência auditiva sensorioneural apresenta uma maior dificuldade para compreender a fala em meio ao ruído em comparação à criança normo-ouvinte. Portanto é importante considerar o uso de recursos, como o sistema de frequência modulada (FM), que auxiliam os usuários de aparelho de amplificação sonora individual (AASI) e implante coclear (IC) no reconhecimento de fala no ruído. OBJETIVO: verificar o benefício do sistema de FM em crianças com deficiência auditiva sensorioneural usuárias de AASI e/ou IC. METODOLOGIA: Participaram do estudo 30 crianças com idades entre 6 e 13 anos divididas em três grupos: grupo 1 (adaptação bimodal), grupo 2 (adaptação bilateral de AASI) e grupo controle (normo-ouvintes). Os sujeitos foram submetidos a uma avaliação do reconhecimento de fala no ruído, sendo que os sujeitos do grupo de estudo 1 e 2 foram submetidos a avaliação com e sem o sistema de FM. RESULTADOS: O sistema de FM apresentou benefícios estatisticamente significantes para os usuários de AASI e IC. A média de melhora com o sistema de FM foi de 9,7dB relação S/R para o grupo 1 e 17,2dB relação sinal/ruído para o grupo 2. A comparação com o grupo controle evidenciou que para uma criança usuária de AASI e/ou IC pode ser necessário uma melhora na relação S/R maior que 10dB a fim de alcançar o mesmo grau de reconhecimento de fala de crianças normo-ouvintes. CONCLUSÃO: O Sistema de FM beneficia crianças com deficiência auditiva usuárias de AASI e/ou IC no reconhecimento de fala no ruído. / The child with sensorineural hearing loss presents more difficulty to understand speech in noise compared with children with normal hearing. Therefore, it is important to consider the use of resources, such as the frequency modulation (FM) system, which help users of hearing aids (HA) and cochlear implants (CI) in speech recognition in noise. OBJECTIVE: verify the benefit of the FM system in children with sensorineural hearing loss users of hearing aid and/or CI. METHOD: We studied 30 children aged between 6 and 13 years divided into three groups: group 1 (bimodal fitting), group 2 (binaural fitting of hearing aids) and control group (normal hearing). The subjects were evaluated as to speech recognition in noise, and subjects of group 1 and 2 underwent evaluation with and without the FM system. RESULTS: The FM system showed statistically significant benefits for users of hearing aid and CI. The mean improvement in the FM system was 9.7 dB signal/noise ratio for group 1 and 17.2 dB signal/noise ratio for group 2. The comparison with the control group showed that for a child user of hearing aid and/or CI it may be necessary an improvement in S/N ratio greater than 10dB in order to achieve the same degree of speech recognition of normal hearing children. CONCLUSION: The FM system benefits children with hearing loss users of hearing aid and/or CI in speech.