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The Influence of a Single Therapeutic Dose of Methadone on Selected Auditory Functions in Patients Addicted to Opioids and Undergoing Substitution Therapy – a Preliminary Study

Tarnowska E., Wicher A., Sęk A., Gorzelańczyk E. J.

Archives of Acoustics

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2018

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Vol. 43, No. 1

137--146

EN

The main purpose of this research was to determine the influence of a therapeutic dose of an opioid drug (methadone) on selected auditory functions in patients addicted to opioids (recognition ICD-10; F11) and undergoing substitution therapy. Various hearing tests were used in this research – pure tone audiometry, impedance audiometry, otoacoustic emission measurement, and a speech in noise test – in two sessions, before and after methadone intake. It was found that methadone causes an improvement in speech intelligibility when speech is presented in speech-like noise, and slightly decreases hearing thresholds [dB HL]. Methadone consumption has no significant impact on distortion product otoacoustic emissions levels (DPOAE). In summary, a prescribed methadone dose does not worsen the hearing of opioid-dependent subjects.

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Doctor Honoris Causa of the Adam Mickiewicz University for Professor Brian C. J. Moore

Sęk A.

Archives of Acoustics

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2016

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Vol. 41, No. 2

351--354

EN

On November 9th, a.d. 2015, Professor Brian Cecil Joseph Moore from Cambridge University (UK), received the title of Doctor Honoris Causa of Adam Mickiewicz University from the hands of His Magnificence, the Rector of the AMU. Professor Brian Moore is a great scholar with a broad, in-depth knowledge and extremely wide research interests in many areas that go far beyond the mainstream of his research. He is a physicist, an acoustician and a psychologist.

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Brian C.J. Moore doktorem honoris causa Uniwersytetu im. Adama Mickiewicza w Poznaniu

Sęk A.

Postępy Fizyki

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2015

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T. 66, z. 1-4

34--36

PL

9 listopada 2015 roku w Sali Lubrańskiego w Collegium Minus odbyła się uroczystość nadania tytułu doktora honoris causa UAM Profesorowi Brianowi C. J. Moore’owi, wybitnemu badaczowi w dziedzinie akustyki psychofizjologicznej.

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The Influence of the Semantic Material on the Assessment of Speech Reception Threshold

Krenz M., Wicher A., Sęk A.

Archives of Acoustics

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2015

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Vol. 40, No. 1

41--50

EN

To determine speech intelligibility using the test suggested by Ozimek et al. (2009), the subject composed sentences with the words presented on a computer screen. However, the number and the type of these words were chosen arbitrarily. The subject was always presented with 18, similarly sounding words. Therefore, the aim of this study was to determine whether the number and the type of alternative words used by Ozimek et al. (2009), had a significant influence on the speech intelligibility. The aim was also to determine an optimal number of alternative words: i.e., the number that did not affect the speech reception threshold (SRT) and not unduly lengthened the duration of the test. The study conducted using a group of 10 subjects with normal hearing showed that an increase in the number of words to choose from 12 to 30 increased the speech intelligibility by about 0.3 dB/6 words. The use of paronyms as alternative words as opposed to random words, leads to an increase in the speech intelligibility by about 0.6 dB, which is equivalent to a decrease in intelligibility by 15 percentage points. Enlarging the number of words to choose from, and switching alternative words to paronyms, led to an increase in response time from approximately 11 to 16 s. It seems that the use of paronyms as alternative words as well as using 12 or 18 words to choose from is the best choice when using the Polish Sentence Test (PST).

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Psychofizyczne i fizyczne metody badań słuchu

Wicher A., Sęk A.

Postępy Fizyki

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2013

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T. 64, z. 3-6

110--115

PL

Psychofizyczne metody badań słuchu dotyczą określenia zależności pomiędzy fizycznymi parametrami fali akustycznej a wrażeniem dźwiękowym, powstającym na skutek stymulacji układu słuchowego sygnałem akustycznym.

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O temacie doktoratu zadecydowałem sam. Rozmowa z profesorem Brianem C. J.Moore’em

Sęk A.

Postępy Fizyki

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2013

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T. 64, z. 3-6

128--133

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U progu zmiany paradygmatu myślenia o edukacji matematycznej - casus wdrażania modelowania matematycznego na poziomie gimnazjum

Maciejak A., Mosiek P., Okrasiński W., Sęk A.

Mathematica Applicanda

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2012

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Vol. 40, No. 1

131-144

PL

Przedmiotem niniejszego opracowania jest przedstawienie doświadczeń edukacyjnych przy wprowadzaniu modelowania matematycznego w programie gimnazjum. Wieloetapowy projekt rozpoczęło kształcenie nauczycieli pod okiem specjalistów do edukacji matematycznej dla potrzeb przemysłu. Na etapie wdrażania kształcenia uczniowie maja pełne kursy ukierunkowane na rozwiązywanie problemów codziennych przez ich precyzyjny opis z wykorzystaniem znanego aparatu matematycznego. Podane są przykłady takich zagadnień oraz analiza efektów tej formy kształcenia matematycznego.

EN

In the paper an experiment related with the introduction of mathematical modelling to the students of a secondary school is described. Some study cases solved by students are presented.

8

Kryteria projektowania alternatorów samochodowych

Sęk A., Bogusz R.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 3

243-248

PL

W artykule przedstawiamy podstawowe kryteria projektowania alternatorów samochodowych oraz szczególne rozwiązania pozwalające na optymalizację konstrukcji w kierunku ich realizacji. Rozważane są: obliczenia własnego modelu, redukcja rozmiarów i masy, modyfikacja obwodu magnetycznego wzbudzenia (zmiana rozmiaru szczeliny powietrznej), poprawa efektywności chłodzenia, zmniejszenie anego hałasu i inne.

EN

In this paper, we present basic criteria, as well as special solutions, permitting on optimalization of construction in direction their realization designing automotive altemators. Own model calculations, reduction in mass and size, modifications in the magnetic excitation circuit (air gap size change), improvement in the cooling efficiency, decrease of the generating noise and others are discussed.

9

A fast method for the determination of psychophysical tuning curves: further refining

Sęk A., Wicher A., Drgas S.

Archives of Acoustics

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2007

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Vol. 32, No. 3

707--728

EN

Psychophysical tuning curves (PTCs) are usually measured by determining the level of a narrowband noise required just to mask a fixed, low-level tone, for several masker centre frequencies. PTCs are often used to assess the frequency selectivity of the auditory system and they have also been used to detect “dead regions” in the cochlea, especially to define the frequency boundaries of the dead regions. However, the traditional method of PTC determination is too-time consuming for use in clinical practice. This paper is concerned with further evaluation and refining of a fast method for determining PTCs, based on the use of a sweeping band of noise. The fixed sinusoidal signal is turned on and off at regular time intervals and is masked by a band of noise, whose centre frequency sweeps over a range of two octaves during four minutes. A Békésy method is used to determine the masker level required for threshold; the subject presses a button to indicate that the signal is inaudible, and releases it when the signal is audible, and the masker level is adjusted accordingly by a computer. The fast method was evaluated using normally hearing subjects and showed good agreement with the results obtained with the use of the traditional method. The shapes of the PTCs, the slopes of the lowand high-frequency skirts, and the positions of the minima were very similar when the fast and the traditional methods were used. However from the point of view of clinical usage the determination of the PTC tip, that is the masker centre frequency at which the masker level is lowest is the most important issue. The position of the PTC minimum with reference to the tone frequency indicates the presence of a dead region. Therefore, in this study several methods of the PTC minimum estimation were evaluated and compared. It has turned out that a fitting method of a single PTC by means of a square function yielded the best results. The method gave the smallest standard deviation, the highest kurtosis and the narrowest range of the PTC minima.

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Speech intelligibility in various spatial configurations of background noise

Kociński J., Sęk A.

Archives of Acoustics

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2005

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Vol. 30, No. 2

173-191

EN

This study is concerned with the influence of spatial separation of disturbing sources of noise on the speech intelligibility. Spatial separation of speech and disturbing sources without changing their acoustic power may contribute to the significant improvement in the speech intelligibility. This problem has been recently analysed in many papers [1-5]. These works have confirmed an important role of the spatial configuration of sources. However, there have been no work investigating this problem for nonsense words (logatoms) that may provide more rigorous tests of this phenomenon. Moreover, this problem has not been analysed for Polish speech. It is important to emphasize that the acoustic and phonetic properties of Polish speech are somewhat different from those of English one. Therefore, the attempt to investigate the influence of the spatial separation of sound sources was made in this study. In the situation with more than one spatially separated disturbances, there may occur a so-called spatial suppression phenomenon, that is "mutual suppression'' of disturbing sounds in the auditory system that brings about an increase in the speech intelligibility. This phenomenon is also called the spatial unmasking of speech [5, 6]. The research consist in determination of the speech intelligibility in the presence of one or two statistically independent speech-shaped noise sources varying in configuration. Only two pairs of the spatial configurations were investigated. Character of the dependences obtained in the study implies that the spatial suppression occurs in certain configurations of sources only. This effect brings about an increase in the speech intelligibility and can be explained on the basis of the binaural masking level difference (BMLD). It seems then that the BMLD may be a more general phenomenon and includes not only difference in the detection threshold of a pure tone masked by noise but also the improvement in the speech intelligibility, while speech is presented at the background of disturbing signals.

11

Binaural masking of amplitude modulation

Kordus M., Sęk A., Kociński J.

Archives of Acoustics

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2005

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Vol. 30, No. 1

5-17

EN

A new concept concerned with the transformation of acoustic stimuli in the auditory system postulates the existence of a form of spectral analysis applied to the amplitude changes of the stimuli. It is assumed that this analysis takes place in the so-called modulation filters, i.e. bandpass linear filters tuned to different rates of the amplitude changes. The most striking argument supporting this idea is an effect of masking in the amplitude modulation domain whose nature can be easily explained basing on this concept. As the modulation filters are situated on the higher levels of the auditory system, it is also assumed that this form of masking is entirely a central process. However, most of the studies concerned with masking in the modulation domain used monaural listening only. Therefore, the main purpose of the presented here experiments was to investigate whether this type of masking is entirely a central process. Using a Three-Alternative Forced-Choice (3AFC) procedure the binaural and monaural masked thresholds of amplitude modulation were determined. A sinusoidal carrier at a frequency of 4 kHz was amplitude modulated by a specially designed band of noise characterized by a very low value of the crest factor, which was used as a masking signals. Different bandwidths of the modulating masking signals were used as well as different center frequencies to investigate whether the masking patterns in the modulation domain depend on the masker bandwidth and its center frequency. The modulating target (masked) signal was a pure tone at a frequency range from 2 to 256 Hz. Both modulating signals were applied to the same sinusoidal carrier signal. The most effective masking was noticed when the rate of the sinusoidal modulation was close to the center frequency of the masking signal or when it was in its spectral range and decreased outside of this range. The character of this dependence confirms the existence of some form of a frequency selectivity in the modulation rate domain similarly to the audible frequency domain. The thresholds for monaural and binaural listening were very close to each other. This implies that masking in the modulation domain is a central process.

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Elektrochemiczne źródła energii stosowane w pojazdach samochodowych

Polakowski K., Sęk A.

Przegląd Elektrotechniczny

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2004

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R. 80, nr 7-8

688-692

PL

Artykuł ten daje ogólne spojrzenie na stan obecny współczesnych elektrochemicznych źródeł energii elektrycznej w zastosowaniach samochodowych. Przedstawiono różne typy ogniw i akumulatorów elektrochemicznych. Ogniwa paliwowe zostały uznane za najbardziej obiecujące do zastosowań samochodowych.

EN

This paper provides an overview of present status of the contemporary electrochemical sources of electrical energy in the automotive applications. Different types of the electrochemical cells and batteries are presented. The fuel cells were chosen as the most promising for automotive applications.

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Analiza pola magnetycznego w rozruszniku samochodowym z magnesami trwałymi i przekładnią planetarną

Sęk A., Polakowski K.

Przegląd Elektrotechniczny

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2004

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R. 80, nr 7-8

702-705

PL

W artykule omówiono podstawowe cechy rozruszników z magnesami trwałymi i przekładnią planetarną. Przedstawiono wyniki obliczeń przy użyciu programu PC Opera rozkładu pola magnetycznego w przekroju poprzecznym rozrusznika. W pracy wyznaczono moment rozrusznika w funkcji prądu obciążenia.

EN

The article describes the basic features of the electric engine starters based on permanent magnets and the planetar gear design. It also presents the calculation results obtained by using the PC Opera software, showing the transverse cross-sectional electromagnetic field distribution inside the starter. The torsional moment on the starter shaft nas been evaluated as the function of the load current.

14

Monaural and binaural detection thresholds of amplitude modulation

Kordus M., Sęk A.

Archives of Acoustics

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2004

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Vol. 29, no. 4

537-553

EN

This study is concerned with the amplitude modulation (AM) detection thresholds for monaural and binaural listening. In the first experiment, using a Two-Alternative Forced-Choice (2AFC) method with an adaptive procedure 2-up 1-down, the monaural and binaural AM detection thresholds were measured. Sinusoidal carrier at a frequency of 160, 500, 1000 or 4000 Hz was amplitude-modulated by a single sinusoidal modulator at a frequency of 4, 32, 64 or 128 Hz. Due to a significant intersubject scatter of the results it was impossible to estimate the difference between the thresholds determined for monaural and binaural presentation of the stimuli. Therefore, in the next experiment, psychometric functions for AM detection for both monaural and binaural listening were determined. This experiment was carried out for sinusoidal carriers at frequencies of 5000, 2000 and 6000 Hz and for sinusoidal modulator at frequencies of 4, 64 and 128 Hz. The results of this experiment showed a statistically significant difference between slopes of the psychometric function (after the percent of correct responses was converted to the detectability, d', domain) for monaural and binaural stimuli presentation. Assuming that the AM threshold coincided with d' = 1 it can be stated that monaural and binaural AM thresholds are significantly different.

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Intelligibility of speech processed by a spectral contrast enhancement procedure and a binaural procedure

Sęk A., Skrodzka E., Ozimek E., Wicher A.

Archives of Acoustics

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2004

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Vol. 29, no. 1

25-34

EN

The study reported was undertaken as an attempt to improve the intelligibility of selected speech signals (numerical test) masked by a speech-shaped noise, by a proposed algorithm of the speech signal processing based on the spectral contrast enhancement and binaural procedure. The spectral contrast enhancement involved the transformation of the speech signal spectrum to achieve an increase in the level of the amplitude between subsequent minima and maxima of individual formants. The binaural procedure involved the determination of the interaural time difference (ITD) and the interaural intensity difference (IID) in order to select and enhance the fragments reaching the listener from the front. The intelligibility of speech processed by the algorithm was compared to that of the unprocessed speech for different spatial separations between the signal and the noise sources and for a few signal to noise ratios. The results have shown that the intelligibility of the speech presented against the noise significantly depends on the angle between the directions of the signal and the noise. The intelligibility of speech is much larger when the noise and the speech reach the observer from different directions, i.e. when their sources are spatially separated. In general, the algorithm improves the intelligibility of numerical tests presented at the background of the noise by a few percent and the greatest improvement has been observed for low signal to noise ratios. The algorithm performance was different for each hearing impaired subject with binaural hearing loss. To get an objective assessment of the algorithm performance it should be optimised and tested on a larger group of subjects for more diverse sound material.

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Wykorzystanie sieci GSM do komunikacji wybranymi funkcjami pojazdu samochodowego

Grzejszczyk E., Sęk A.

Prace Naukowe Politechniki Warszawskiej. Elektryka

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2003

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z. 129

171--175

PL

Komunikat omawia zasadę działania zaprojektowanego i oprogramowanego w ZKUE PW urządzenia mikroprocesorowego pracującego w technologii GSM, monitorującego wybrane zdarzenia w pracy pojazdu samochodowego oraz jego komunikację głosową z właścicielem pojazdu. W dalszej części artykuł zawiera charakterystykę tzw. Terminali GSM, do których zalicza się omówione w części pierwszej artykułu, urządzenie. Artykuł omawia również wybrane zastosowania praktyczne terminali oraz wskazuje kierunek ich rozwoju.

EN

This essay presents the functioning of the microprocessor element in GSM technology designed and programmed in ZKUE PW that monitors the selected elements of the functioning of the car as well its voice communication with the user of this vehicle. Furthermore, the characteristic of so called GSM Terminals (the microprocessor element presented above is an example of such a GSM Terminal) is presented. The essay also describes the selected practical implementations of the terminals and analyses their development.

17

Nowoczesne alternatory kompaktowe

Sęk A., Grzejszczyk E.

Prace Naukowe Politechniki Warszawskiej. Elektryka

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2003

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z. 129

85--98

PL

W artykule przedstawiono współczesne alternatory kompaktowe. Zmniejszenie masy i wymiarów oraz poprawę właściwości eksploatacyjnych tego rodzaju alternatorów osiągnięto dzięki modyfikacji obwodu magnetycznego wzbudzenia, polegającej na zmniejszeniu wielkości szczeliny powietrznej i kształtu biegunów kłowych. Znacznie zwiększono jego prędkość obrotową, zwiększając przełożenie przekładni alternator/silnik spalinowy. Ponadto przeniesiono wentylator usytuowany na zewnątrz obudowy do wewnątrz, gdzie stanowi on integralną część wirnika. Takie rozwiązanie polepszyło efektywność chłodzenia i zmniejszyło szumy generowane przez alternator. W pracy przedstawiono budowę i charakterystyki alternatorów kompaktowych na przykładzie alternatorów firmy Bosch. Zaprezentowane obliczenia własnego modelu alternatora wykazały, że osiągnięte parametry techniczne są istotnie lepsze od parametrów alternatorów konwencjonalnych.

EN

In this paper, we present modem compact alternators. Compact alternators are smaller (about 15%) and weigh less (about 25%) than conventional alternators of similar power. The reduction in mass and size of this kind of alternator, as well as the improvement in their exploitation properties was possible due to a modification in the magnetic excitation circuit. This modification relies on the reduction in the air-gap size and in changes of the claw pole shapes. In addition, the transfer of a ventilaiting fan from the circuit's casing to its interior and the integration of this fan with the circuit's rotor created an increase in the rotation velocity. This resulted in an improvement in the cooling efficiency, as well as in a decrease of the generating noise. In this paper we depict the structure and characteristics of compact alternators using models from the Bosch company as examples.

18

Detection of the amplitude modulation for modulating signals characterised by different crest factors

Rybicka W., Sęk A.

Archives of Acoustics

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2003

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Vol. 28, no. 4

273-292

EN

This study is concerned with the detection of amplitude modulation (AM) of a tonal signal for modulating signals characterised by a different crest factor and a low frequency. The purpose was to show that the root-mean-square (RMS) value of the modulating signal is not a sufficient measure of the modulation perceived by listeners. In the first experiment, using the 2AFC method with an adaptation procedure, the AM detection thresholds were determined for a 1-kHz tone modulated with 3-component harmonic complexes, the components of which had the same amplitudes. The starting phases of the complexes were chosen arbitrary to obtain the highest (2.44) and the lowest (1.89) values of the crest factor of the same root-mean-square values. The fundamental frequencies of the modulator were 1, 2 Hz and 4 Hz. The AM thresholds gathered for these modulators were characterized by a certain scatter that makes impossible the drawing of any conclusion concerning the influence of the crest factor on those thresholds. Therefore in the second experiment psychometric functions were determined for the detection of AM using the same carrier and modulators. However, the results of this experiment did not provide unambiguous evidence for a statistically significant effect of the crest factor on the psychometric functions and the AM threshold values. Since the modulators used in the first two experiments were characterised by too small differences in the crest factor, the modulating signal in the third experiment was a harmonic complex consisting of ten pure tones of the same amplitude. The starting phases of all components were chosen so as to obtain signals characterised by the highest (4.47) and the lowest (1.58) crest factor. For these modulating signals, the probability of AM detection was found to depend significantly on the crest factor, i.e. the detection of the AM was considerably easier when a modulating waveform characterised by the highest crest factor was used. The results of this experiment suggested that, at least for the low-frequency modulator, the description of the AM thresholds by means of the RMS values of the modulator is somehow misleading and does not express properly the abilities of the auditory system to detect low-frequency amplitude changes. It has been also suggested that for a modulating signal of a high crest factor the listeners can follow the amplitude changes over time only when the changes are slow enough, i.e. when sidebands produced by the amplitude modulation are not resolved in the auditory periphery.

19

Wpływ współczynnika szczytu sygnału modulującego na progi modulacji amplitudowej

Rybicka W., Sęk A.

Prace Naukowe Instytutu Telekomunikacji i Akustyki Politechniki Wrocławskiej. Konferencje

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2001

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Vol. 83, nr 27

93-96

EN

This paper is concerned with measurements of amplitude modulated (AM) thresholds of a tone, modulated by means of a signal consisting of three sinusoids of equal amplitudes and low frequencies. By changing starting phases of each sinusoid it was possible to get modulators characterized by different crest factors, keeping constant their root-mean-square (RMS) values. This experiment demonstrated that when amplitude of a tone changed very slowly, AM thresholds did not depend on a crest factor of a modulator even when subject followed instantaneous changes in amplitude of the tone. Therefore, it can be assumed that listener's decision is made based on the RMS value of amplitude changes in a signal.

20

Poprawa kontrastu widmowego samogłosek

Marszałkiewicz M., Sęk A.

Prace Naukowe Instytutu Telekomunikacji i Akustyki Politechniki Wrocławskiej. Konferencje

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2001

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Vol. 83, nr 27

143-146

EN

This paper is concerned with a spectral enhancement of Polish vowels presented in quiet and at a background of a broadband noise. The basic idea of the presented algorithm is to change a spectrum of an input signal to evoke an excitation pattern in the impaired auditory system that would be evoked by the original signal in the normal auditory system. Applying this algorithm, a spectral contrast improvement in Polish vowels was achieved, especially for first three formants. The enhancement, however, strictly depends on the vowel and the procedure changes relative levels of the vowels' formants. The spectral enhancement was achieved both for vowels presented in quiet and at a background of a broadband noise.