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Comparison of the magnetic resonance imaging and acoustocerebrography signals in the assessment of focal cerebral microangiopathic lesions in patients with asymptomatic atrial fibrillation. (Preliminary clinical study results)

Dobkowska-Chudon W., Wrobel M., Frankowska E., Dabrowski A., Karlowicz P., Zegadlo A., Krupienicz A., Nowicki A., Olszewski R.

Hydroacoustics

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2016

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Vol. 19

83--92

EN

Acoustocerebrography (ACG) is a set of techniques designed to capture states of human brain tissue, and its changes. It is based on noninvasive measurements of various parameters obtained by analyzing an ultrasound pulse emitted through the human’s skull. ACG and Magnetic Resonance Imaging (MRI) results were compared in a clinical study assessment of focal white-matter-lesions (WML) in the brains of patients with asymptomatic atrial fibrillation (AAF). The clinical study included 55 patients (age 66.1 ± 6.7 years). According to MRI data, the patients were assigned into four groups depending on the number of lesions: L0 - 0 to 4 lesions, L5 - 5 to 9 lesions, L10 - 10 to 29 lesions, and L30 - 30 or more lesions. As a result, it has been concluded that the ACG method could clearly differentiate the groups L0 (with 0 ÷ 4 lesions) and L30 (with more than 30 lesions) of WML patients. Fisher’s Exact Test shows that this correlation is highly significant (p < 0.001). ACG seems to be a new, effective, method for detecting WML for patients with AAF and can become increasingly useful in both diagnosing, and in stratifying, them. This, in turn, can be helpful in individualizing their treatment, so that the risk of strokes may become essentially reduced.

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On ultrasound classification of stroke risk factors from randomly chosen respondents using non-invasive multispectral ultrasonic brain measurements and adaptive profiles

Wrobel M., Dabrowski A., Kolany A., Olak-Popko A., Olszewski R., Karlowicz P.

Biocybernetics and Biomedical Engineering

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2016

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Vol. 36, no. 1

19--28

EN

In this paper, we present a new brain diagnostic method based on a computer aided multispectral ultrasound diagnostics method (CAMUD). We explored the standard values of the relative time of flight (RIT), as well as the attenuation, ATN, of multispectral longitudinal ultrasound waves propagated non-invasively through the brains of a standard Caucasian volunteer population across different ages and genders. For the interpretation of the volunteers health questionnaire and ultrasound data we explored various clustering and classification algorithms, such as PCA and ANOVA. We showed that the RIT and ATN values provide very good estimators of possible physiological changes in the brain tissue and can differentiate the possible high-risk groups obtained by other groups and methods (Russo et al. [1]; Lloyd-Jones et al. [2]; Medscape [3]). Special attention should be given to the subgroup which included almost 39% of the volunteers. Respondents in this group have a significantly increased minimum ATN value (see Classification Trees). These values are strongly correlated with the identified risk of stroke factors being: age, increased alcohol consumption, cases of heart disease and stroke in the family as already shown by Rusco and as incorporated into Lloyd-Jones et al., ‘‘Heart Disease and Stroke Statistics – 2009 Update’’, by the American Heart Association (AHA) and American Stroke Association (ASA), as updated recently in the 2015 ‘‘Stroke Prevention Guidelines’’.

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Real time recognition of speakers from internet audio stream

Weychan R., Marciniak T., Stankiewicz A., Dabrowski A.

Foundations of Computing and Decision Sciences

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2015

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Vol. 40, No. 3

223--233

EN

In this paper we present an automatic speaker recognition technique with the use of the Internet radio lossy (encoded) speech signal streams. We show an influence of the audio encoder (e.g., bitrate) on the speaker model quality. The model of each speaker was calculated with the use of the Gaussian mixture model (GMM) approach. Both the speaker recognition and the further analysis were realized with the use of short utterances to facilitate real time processing. The neighborhoods of the speaker models were analyzed with the use of the ISOMAP algorithm. The experiments were based on four 1-hour public debates with 7–8 speakers (including the moderator), acquired from the Polish radio Internet services. The presented software was developed with the MATLAB environment.

4

System SOMAX-2 do sterowania i kontroli kombajnów ścianowych

Gizdoń H., Dabrowski A., Świeca O.

Mechanizacja i Automatyzacja Górnictwa

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1999

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nr 4-5

97-99

PL

Przedmiotem artykułu jest ogólna charakterystyka systemu SOMAX-2 do sterowania i kontroli kombajnów ścianowych. Opracowanie prezentuje następujące aspekty systemu: cel budowy i zakres działania systemu; architekturę sprzętową; oprogramowanie systemowe i użytkowe; zdalne monitorowanie pracy kombajnu.

EN

The subject of the article is general characteristic of the SOMAX-2 system for control and monitoring of longwall cutter-loader. The article presents: purpose of construction and principle of the system operation, architecture of hardware, system and applicationsoftware, remote monitoring of a cutter-loader operation.