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Speech is an integral part of the human communication system. Various pathological conditions affect the vocal functions,
inducing speech disorders. Acoustic parameters of speech are commonly used for the assessment of speech disorders and for
monitoring the progress of the patient over the course of therapy. In the last two decades, signal-processing techniques have
been successfully applied in screening speech disorders. In the paper, a novel approach is proposed to classify pathological
speech signals using a local discriminant bases (LDB) algorithm and wavelet packet decompositions. The focus of the paper
was to demonstrate the significance of identifying the signal subspaces that contribute to the discriminatory characteristics
of normal and pathological speech signals in a computationally efficient way. Features were extracted from target subspaces
for classification, and time-frequency decomposition was used to eliminate the need for segmentation of the speech signals.
The technique was tested with a database of 212 speech signals (51 normal and 161 pathological) using the Daubechies wavelet
(db4). Classification accuracies up to 96% were achieved for a two-group classification as normal and pathological speech
signals, and 74% was achieved for a four-group classification as male normal, female normal, male pathological and female
pathological signals. 相似文献
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目的研究农村社区卫生服务对卫生服务公平性的影响。方法以现况调查资料作为调查组,既往调查数据为基线组。应用对比研究方法,从健康公平性、卫生服务利用公平性、卫生服务提供公平性3个方面对武陟县农村卫生服务公平性进行评价。结果调查组有关指标均好于基线组。结论农村社区卫生服务在改善健康公平性、卫生服务利用和提供公平性方面起到积极的作用。 相似文献
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Anita Knopov Emily F. Rothman Shea W. Cronin Lydia Franklin Alev Cansever Fiona Potter Aldina Mesic Anika Sharma Ziming Xuan Michael Siegel David Hemenway 《Journal of the National Medical Association》2019,111(1):62-75
Objective
To investigate the relationship between racial residential segregation and differences in Black-White disparities in overall firearm homicides across U.S states.Methods
Using a linear regression, we evaluated the relationship between racial residential segregation, as measured by the index of dissimilarity, and the Black-White firearm homicide disparity ratio in 32 states over the period 1991-2015. To account for clustering of observations within states, we used a generalized estimating equations approach.Results
After controlling for measures of White and Black deprivation, multivariate analysis showed that racial segregation was positively associated with the Black-White firearm homicide disparity. For each 10-point increase in the index of dissimilarity, the ratio of Black to White firearm homicide rates in a state increased by 39%. After controlling for levels of White and Black deprivation, racial segregation remained negatively associated with White firearm homicide rates and positively associated with Black firearm homicide rates.Conclusions
These findings suggest that racial segregation may increase the disparity in firearm homicide between the Black and White population. 相似文献4.
The shape of neuronal cells strongly resembles botanical trees or roots of plants. To analyze and compare these complex three-dimensional
structures it is important to develop suitable methods. We review the so called tree-edit-distance known from theoretical
computer science and use this distance to define dissimilarity measures for neuronal cells. This measure intrinsically respects
the tree-shape. It compares only those parts of two dendritic trees that have similar position in the whole tree. Therefore
it can be interpreted as a generalization of methods using vector valued measures. Moreover, we show that our new measure,
together with cluster analysis, is a suitable method for analyzing three-dimensional shape of hippocampal and cortical cells.
相似文献
Gabriel Wittum (Corresponding author)Email: |
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Rebecca Allen Simon Burgess Russell Davidson Frank Windmeijer 《Econometrics Journal》2015,18(1):40-66
The most widely used measure of segregation is the so‐called dissimilarity index. It is now well understood that this measure also reflects randomness in the allocation of individuals to units (i.e. it measures deviations from evenness, not deviations from randomness). This leads to potentially large values of the segregation index when unit sizes and/or minority proportions are small, even if there is no underlying systematic segregation. Our response to this is to produce adjustments to the index, based on an underlying statistical model. We specify the assignment problem in a very general way, with differences in conditional assignment probabilities underlying the resulting segregation. From this, we derive a likelihood ratio test for the presence of any systematic segregation, and bias adjustments to the dissimilarity index. We further develop the asymptotic distribution theory for testing hypotheses concerning the magnitude of the segregation index and show that the use of bootstrap methods can improve the size and power properties of test procedures considerably. We illustrate these methods by comparing dissimilarity indices across school districts in England to measure social segregation. 相似文献
6.
Recent technological advances with the scalp EEG methodology allow researchers to record electric fields generated in the
human brain using a large number of electrodes or sensors (e.g. 64–256) distributed over the head surface (multi-channel recording).
As a consequence, such high-density ERP mapping yields fairly dense ERP data sets that are often hard to analyze comprehensively
or to relate straightforwardly to specific cognitive or emotional processes, because of the richness of the recorded signal
in both the temporal (millisecond time-resolution) and spatial (multidimensional topographic information) domains. Principal
component analyses (PCA) and topographic analyses (combined with distributed source localization algorithms) have been developed
and successfully used to deal with this complexity, now offering powerful alternative strategies for data-driven analyses
in complement to more traditional ERP analyses based on waveforms and peak measures. In this paper, we first briefly review
the basic principles of these approaches, and then describe recent ERP studies that illustrate how they can inform about the
precise spatio-temporal dynamic of emotion processing. These studies show that the perception of emotional visual stimuli
may produce both quantitative and qualitative changes in the electric field configuration recorded at the scalp level, which
are not apparent when using conventional ERP analyses. Additional information gained from these approaches include the identification
of a sequence of successive processing stages that may not fully be reflected in ERP waveforms only, and the segregation of
multiple or partly overlapping neural events that may be blended within a single ERP waveform. These findings highlight the
added value of such alternative analyses when exploring the electrophysiological manifestations of complex and distributed
mental functions, as for instance during emotion processing. 相似文献
7.
Jonathan S. Schildcrout Melissa A. Basford Jill M. Pulley Daniel R. Masys Dan M. Roden Deede Wang Christopher G. Chute Iftikhar J. Kullo David Carrell Peggy Peissig Abel Kho Joshua C. Denny 《Journal of biomedical informatics》2010,43(6):914-923
We describe a two-stage analytical approach for characterizing morbidity profile dissimilarity among patient cohorts using electronic medical records. We capture morbidities using the International Statistical Classification of Diseases and Related Health Problems (ICD-9) codes. In the first stage of the approach separate logistic regression analyses for ICD-9 sections (e.g., “hypertensive disease” or “appendicitis”) are conducted, and the odds ratios that describe adjusted differences in prevalence between two cohorts are displayed graphically. In the second stage, the results from ICD-9 section analyses are combined into a general morbidity dissimilarity index (MDI). For illustration, we examine nine cohorts of patients representing six phenotypes (or controls) derived from five institutions, each a participant in the electronic MEdical REcords and GEnomics (eMERGE) network. The phenotypes studied include type II diabetes and type II diabetes controls, peripheral arterial disease and peripheral arterial disease controls, normal cardiac conduction as measured by electrocardiography, and senile cataracts. 相似文献
8.
目的:对酒石酸美托洛尔片国产仿制药与原研药进行体外溶出度比较,为质量一致性评价提供依据。方法参照中国药典2010版二部酒石酸美托洛尔片的质量标准,选取50mg规格样品,采用4种不同的溶出介质对国内8家企业生产的仿制药和原研药进行体外溶出行为考察,并采用差异因子f1法、相似因子f2法和直接比较法来评价仿制药与原研药溶出行为的一致性。结果8家仿制药溶出行为参差不齐,按直接比较法只有1家仿制药在四种溶出介质中的溶出曲线均与原研药一致,只在两种或一种溶出介质中的溶出曲线与原研药一致的情况较多。结论国内企业生产的酒石酸美托洛尔片仿制药与原研药存在体外溶出行为不一致性,处方、制剂工艺、辅料的选用方面需要进一步研究,以达到仿制药与原研药体外溶出行为一致性和质量一致性。同时,要结合生物等效性试验,对该品种的国产仿制药和原研药的一致性作出综合的评价。 相似文献
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