Autor: Karwat, P. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Spatial and Frequency Compounding in Application to Attenuation Estimation in Tissue
Autorzy:: Klimonda, Z.
Litniewski, J.
Karwat, P.
Nowicki, A.
Powiązania:: https://bibliotekanauki.pl/articles/177604.pdf
Data publikacji:: 2014
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: tissue attenuation estimation
parametric imaging
synthetic aperture
spatial compounding
frequency compounding
Opis:: The soft tissue attenuation is an interesting parameter from medical point of view, because the value of attenuation coefficient is often related to the state of the tissue. Thus, the imaging of the attenuation coefficient distribution within the tissue could be a useful tool for ultrasonic medical diagnosis. The method of attenuation estimation based on tracking of the mean frequency changes in a backscattered signal is presented in this paper. The attenuation estimates are characterized by high variance due to stochastic character of the backscattered ultrasonic signal and some special methods must be added to data processing to improve the resulting images. The following paper presents the application of Spatial Compounding (SC), Frequency Compounding (FC) and the combination of both. The resulting parametric images are compared by means of root-mean-square errors. The results show that combined SC and FC techniques significantly improve the quality and accuracy of parametric images of attenuation distribution.
Źródło:: Archives of Acoustics; 2014, 39, 4; 519-527
0137-5075
Pojawia się w:: Archives of Acoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 2.

Tytuł:: Research and Medical Transcranial Doppler System
Autorzy:: Lewandowski, M.
Walczak, M.
Karwat, P.
Witek, B.
Karłowicz, P.
Powiązania:: https://bibliotekanauki.pl/articles/177389.pdf
Data publikacji:: 2016
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: Doppler system
digital signal processing
hardware-software partitioning
field programmable gate array (FPGA)
Opis:: A new ultrasound digital transcranial Doppler system (digiTDS) is introduced. The digiTDS enables diagnosis of intracranial vessels which are rather difficult to penetrate for standard systems. The device can display a color map of flow velocities (in time-depth domain) and a spectrogram of a Doppler signal obtained at particular depth. The system offers a multigate processing which allows to display a numer of spectrograms simultaneously and to reconstruct a flow velocity profile. The digital signal processing in digiTDS is partitioned between hardware and software parts. The hardware part (based on FPGA) executes a signal demodulation and reduces data stream. The software part (PC) performs the Doppler processing and display tasks. The hardware-software partitioning allowed to build a flexible Doppler platform at a relatively low cost. The digiTDS design fulfills all necessary medical standards being a new useful tool in the transcranial field as well as in heart velocimetry research.
Źródło:: Archives of Acoustics; 2016, 41, 4; 773-781
0137-5075
Pojawia się w:: Archives of Acoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 3.

Tytuł:: Noninvasive Imaging of Thermal Fields Induced in Soft Tissues In Vitro by Pulsed Focused Ultrasound Using Analysis of Echoes Displacement
Autorzy:: Karwat, P.
Litniewski, J.
Kujawska, T.
Secomski, W.
Krawczyk, K.
Powiązania:: https://bibliotekanauki.pl/articles/176451.pdf
Data publikacji:: 2014
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: high intensity focused ultrasound
HIFU
therapeutic ultrasound
ultrasonic imaging
echo strain estimation
Opis:: Therapeutic and surgical applications of focused ultrasound require monitoring of local temperature rises induced inside tissues. From an economic and practical point of view ultrasonic imaging techniques seem to be the most suitable for the temperature control. This paper presents an implementation of the ultrasonic echoes displacement estimation technique for monitoring of local temperature rise in tissue during its heating by focused ultrasound The results of the estimation were compared to the temperature measured with thermocouple. The obtained results enable to evaluate the temperature fields induced in tissues by pulsed focused ultrasonic beams using non-invasive imaging ultrasound technique.
Źródło:: Archives of Acoustics; 2014, 39, 1; 139-144
0137-5075
Pojawia się w:: Archives of Acoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 4.

Tytuł:: Data Reduction Method for Synthetic Transmit Aperture Algorithm
Autorzy:: Karwat, P.
Klimonda, Z.
Sęklewski, M.
Lewandowski, M.
Nowicki, A.
Powiązania:: https://bibliotekanauki.pl/articles/177848.pdf
Data publikacji:: 2010
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: ultrasonic imaging
synthetic transmit aperture
data reduction
effective aperture
reciprocity
Opis:: Ultrasonic methods of human body internal structures imaging are being continuously enhanced. New algorithms are created to improve certain output parameters. A synthetic aperture method (SA) is an example which allows to display images at higher frame-rate than in case of conventional beam-forming method. Higher computational complexity is a limitation of SA method and it can prevent from obtaining a desired reconstruction time. This problem can be solved by neglecting a part of data. Obviously it implies a decrease of imaging quality, however a proper data reduction technique would minimize the image degradation. A proposed way of data reduction can be used with synthetic transmit aperture method (STA) and it bases on an assumption that a signal obtained from any pair of transducers is the same, no matter which transducer transmits and which receives. According to this postulate, nearly a half of the data can be ignored without image quality decrease. The presented results of simulations and measurements with use of wire and tissue phantom prove that the proposed data reduction technique reduces the amount of data to be processed by half, while maintaining resolution and allowing only a small decrease of SNR and contrast of resulting images.
Źródło:: Archives of Acoustics; 2010, 35, 4; 635-642
0137-5075
Pojawia się w:: Archives of Acoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 5.

Tytuł:: Preeliminary results: comparison of different schemes of synthetic aperture technique in ultrasonic imaging
Autorzy:: Sęklewski, M.
Karwat, P.
Klimonda, Z.
Lewandowski, M.
Nowicki, A.
Powiązania:: https://bibliotekanauki.pl/articles/331979.pdf
Data publikacji:: 2010
Wydawca:: Polskie Towarzystwo Akustyczne
Opis:: The Synthetic Aperture (SA) methods are widespread and successfully used in radar technology, as well as in the sonar systems. The advantages of high framerate and its relatively good resolution in the whole area of scanning, make this technique an object of interest in medical imaging methods such as ultrasonography (US). This paper describes the possible usage of the SA method in ultrasound imaging. The introduction to the principles of the SA technique in ultrasonography is presented. The measurements of different SA schemes were conducted using the set-up consisting of the research ultrasonograph module, the PC and the special wire phantom. The results for different schemes of image reconstruction are presented. Particularly the Synthetic Transmit Aperture (STA) technique was concerned. Results of the STA method are discussed in this paper.
Źródło:: Hydroacoustics; 2010, 13; 243-252
1642-1817
Pojawia się w:: Hydroacoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 6.

Tytuł:: Application of ultrasound to noninvasive imaging of temperature distribution induced in tissue
Autorzy:: Karwat, P.
Kujawska, T.
Secomski, W.
Gambin, B.
Litniewski, J.
Powiązania:: https://bibliotekanauki.pl/articles/332286.pdf
Data publikacji:: 2016
Wydawca:: Polskie Towarzystwo Akustyczne
Tematy:: HIFU
echo phase shift
parametric imaging
velocity/brightness CNR
Opis:: Therapeutic and surgical applications of High Intensity Focused Ultrasound (HIFU) require monitoring of local temperature rises induced inside tissues. It is needed to appropriately target the focal plane, and hence the whole focal volume inside the tumor tissue, prior to thermo-ablative treatment, and the beginning of tissue necrosis. In this study we present an ultrasound method, which calculates the variations of the speed of sound in the locally heated tissue. Changes in velocity correspond to temperature change. The method calculates a 2D distribution of changes in the sound velocity, by estimation of the local phase shifts of RF echo-signals backscattered from the heated tissue volume (the focal volume of the HIFU beam), and received by an ultrasound scanner (23). The technique enabled temperature imaging of the heated tissue volume from the very inception of heating. The results indicated that the contrast sensitivity for imaging of relative changes in the sound speed was on the order of 0.06%; corresponding to an increase in the tissue temperature by about 2 °C.
Źródło:: Hydroacoustics; 2016, 19; 219-228
1642-1817
Pojawia się w:: Hydroacoustics
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 7.

Tytuł:: The Application of Ultrasonic Methods to Flow Measurement and Detection of Microembolus in Heart Prostheses
Autorzy:: Gawlikowski, M.
Lewandowski, M.
Nowicki, A.
Kustosz, R.
Walczak, M.
Karwat, P.
Karłowicz, P.
Powiązania:: https://bibliotekanauki.pl/articles/1399342.pdf
Data publikacji:: 2013-09
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 43.35.Yb
43.80.Qf
43.35.Ae
Opis:: For the last 20 years the world cardiosurgery has presented a considerable change of attitude to mechanical circulatory support. In spite of technological progress the main problems in ventricular assist devices are: thrombosis and low accuracy of flow measurements. In this paper the prototype of multi-gate Doppler flowmeter intended for cardiac assist system ReligaHeart EXT has been presented as well as the possibility of ultrasonic microembolus detection.
Źródło:: Acta Physica Polonica A; 2013, 124, 3; 417-420
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 8.

Tytuł:: Pomiary temperatury łuku palącego się w szczelinie międzystykowej aparatów elektrycznych za pomocą spektrofotometru światłowodowego
Spectrophotometric testing of an electric arc of alternating current
Autorzy:: Żukowski, P.
Kozak, C.
Karwat, C.
Powiązania:: https://bibliotekanauki.pl/articles/153223.pdf
Data publikacji:: 2008
Wydawca:: Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:: łączniki
łuk elektryczny
temperatura
widma
spektrofotometr
switches
electric arc
temperature
spectra
spectrophotometer
Opis:: W artykule opisano spektrofotometryczną metodę określania temperatury łuku elektrycznego palącego się w szczelinie międzystykowej łącznika na podstawie zarejestrowanych widm ciągłych, oraz wpływ rodzaju materiału styków i ich cech konstrukcyjnych na jej wartość.
The article presents a spectrophotometric method for determining temperature of electric arc burning in an inter-contact gap of a switch based on recorded continuous spectra. Influence of the material and design of the contacts on the temperature values is also discussed.
Źródło:: Pomiary Automatyka Kontrola; 2008, R. 54, nr 10, 10; 682-685
0032-4140
Pojawia się w:: Pomiary Automatyka Kontrola
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 9.

Tytuł:: Importance of most frequent needs of the disabled in shaping areas of support in public health. Part III. Scopes of locomotor capabilities of the disabled from the aspect of demographic and social conditioning and problems hindering daily functioning
Autorzy:: Kołłątaj, B.
Karwat, I.D.
Kołłątaj, W.P.
Powiązania:: https://bibliotekanauki.pl/articles/28761631.pdf
Data publikacji:: 2023
Wydawca:: Instytut Medycyny Wsi
Źródło:: Annals of Agricultural and Environmental Medicine; 2023, 30, 1; 195-203
1232-1966
Pojawia się w:: Annals of Agricultural and Environmental Medicine
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 10.

Tytuł:: Tooth loss among adult rural and urban inhabitants of the Lublin Region
Autorzy:: Panasiuk, L.
Kosiniak-Kamysz, W.
Horoch, A.
Paprzycki, P.
Karwat, D.
Powiązania:: https://bibliotekanauki.pl/articles/49895.pdf
Data publikacji:: 2013
Wydawca:: Instytut Medycyny Wsi
Opis:: Dental diseases and tooth loss result in various health, psychological, and even social problems. The objective of the study was determination of the number of missing teeth among adult rural and urban inhabitants of the Lublin Region, and whether or not there is a relationship between missing teeth and place of residence, and other socio-economic factors, such as: gender, age, education level and the occupation performed (farmer/non-farmer). Data concerning the number of missing teeth were collected from 3,388 individuals. The mean number of missing teeth among the respondents in the study was 13.6. This mean value was significantly higher among the rural than urban inhabitants. Tooth loss was significantly more often found among females than males, this relationship being statistically significant only in the subpopulation of rural inhabitants. According to expectations, the largest number of missing teeth was found in respondents aged over 60, among those aged 31–60 this number was nearly 2.5- fold smaller, while the smallest number of missing teeth was observed among respondents aged 18–30. The largest number of missing teeth was noted among respondents who possessed incomplete elementary or elementary education, followed by those with elementary vocational and secondary school/post-secondary school education, whereas this number was the smallest among respondents who had university education level. Farmers had a significantly larger number of missing teeth, compared to respondents who performed non-agricultural occupations. Using an analysis of regression, the relationship was confirmed between the number of missing teeth, and the respondents’ gender, age, education level, place of residence, and occupation performed. Discrimination analysis was applied to show the relationship between the occurrence of total edentulism and the respondents’ age, gender, education level and place of residence. It was observed that age was the variable which most strongly discriminated the occurrence of this characteristic, followed by education level, as well as gender and place of residence, which were the weakest discriminatory variables.
Źródło:: Annals of Agricultural and Environmental Medicine; 2013, 20, 3
1232-1966
Pojawia się w:: Annals of Agricultural and Environmental Medicine
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 11.

Tytuł:: Research priorities in the domain of disability – correlation between health and social characteristics. A Polish example
Autorzy:: Kołłątaj, B.
Kołłątaj, W.P.
Cipora, E.
Sygit, K.
Karwat, I.D.
Powiązania:: https://bibliotekanauki.pl/articles/28761743.pdf
Data publikacji:: 2022
Wydawca:: Instytut Medycyny Wsi
Źródło:: Annals of Agricultural and Environmental Medicine; 2022, 29, 4; 463-470
1232-1966
Pojawia się w:: Annals of Agricultural and Environmental Medicine
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 12.

Tytuł:: Importance of most frequent needs of the disabled in shaping areas of support in public health. Part 1. Analysis of selected demographic and social characteristics of the disabled with consideration of the causes of body dysfunction, legal disability status, and selected characteristics of the state of health
Autorzy:: Kołłątaj, B.
Kołłątaj, W.P.
Panasiuk, L.
Sobieszczański, J.
Karwat, I.D.
Powiązania:: https://bibliotekanauki.pl/articles/28761926.pdf
Data publikacji:: 2021
Wydawca:: Instytut Medycyny Wsi
Źródło:: Annals of Agricultural and Environmental Medicine; 2021, 28, 4; 692-704
1232-1966
Pojawia się w:: Annals of Agricultural and Environmental Medicine
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 13.

Tytuł:: Anti-vaccine movements – a form of social activity for health care, ignorance or diversion aimed at destabilizing the health situation? Part 1. Epidemiological safety. Vaccinations – pros and cons
Autorzy:: Kołłątaj, W.P.
Kołłątaj, B.
Panasiuk, L.
Sobieszczański, J.
Karwat, I.D.
Powiązania:: https://bibliotekanauki.pl/articles/28762966.pdf
Data publikacji:: 2020
Wydawca:: Instytut Medycyny Wsi
Źródło:: Annals of Agricultural and Environmental Medicine; 2020, 27, 4; 544-552
1232-1966
Pojawia się w:: Annals of Agricultural and Environmental Medicine
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 14.

Tytuł:: Relationship between the components of disability definition and the effectiveness of rehabilitation measures as a process
Autorzy:: Kołłątaj, W.P.
Kołłątaj, B.
Cipora, E.
Sygit, K.
Karwat, I.D.
Powiązania:: https://bibliotekanauki.pl/articles/28763028.pdf
Data publikacji:: 2023
Wydawca:: Instytut Medycyny Wsi
Źródło:: Annals of Agricultural and Environmental Medicine; 2023, 30, 4; 595-601
1232-1966
Pojawia się w:: Annals of Agricultural and Environmental Medicine
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 15.

Tytuł:: CLA - właściwości prozdrowotne
CLA - health benefits/health promoting properties
Autorzy:: Karwat, J.
Gil-Kulik, P.
Kotula, L.
Niedojadlo, A.
Kocki, J.
Sawiuk, M.
Powiązania:: https://bibliotekanauki.pl/articles/4410.pdf
Data publikacji:: 2013
Wydawca:: Instytut Medycyny Wsi
Tematy:: sprzezony kwas linolowy
wlasciwosci prozdrowotne
otylosc
suplementy diety
odchudzanie
Źródło:: Medycyna Ogólna i Nauki o Zdrowiu; 2013, 19(48), 4
2083-4543
Pojawia się w:: Medycyna Ogólna i Nauki o Zdrowiu
Dostawca treści:: Biblioteka Nauki