Ryszard Tymkiewicz 

Ostatnie publikacje
1.  Litniewski J., Cieślik L., Lewandowski M., Tymkiewicz R., Zienkiewicz B., Nowicki A., Ultrasonic Scanner for In Vivo Measurement of Cancellous Bone Properties From Backscattered Data, IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL, ISSN: 08853010, DOI: 10.1109/TUFFC.2012.2347, Vol.59, No.7, pp.14701477, 2012 Streszczenie: A dedicated ultrasonic scanner for acquiring RF echoes backscattered from the trabecular bone was developed. The design of device is based on the goal of minimizing of custom electronics and computations executed solely on the main computer processor and the graphics card. The electronic encoderdigitizer module executing all of the transmission and reception functions is based on a single lowcost field programmable gate array (FPGA). The scanner is equipped with a mechanical sectorscan probe with a concave transducer with 50 mm focal length, center frequency of 1.5 MHz and 60% bandwidth at −6 dB. The example of femoral neck bone examination shows that the scanner can provide ultrasonic data from deeply located bones with the ultrasound penetrating the trabecular bone up to a depth of 20 mm. It is also shown that the RF echo data acquired with the scanner allow for the estimation of attenuation coefficient and frequency dependence of backscattering coefficient of trabecular bone. The values of the calculated parameters are in the range of corresponding in vitro data from the literature but their variation is relatively high. Słowa kluczowe: cancellous bone, broadband ultrasound attenuation, FPGA Afiliacje autorów:
 35p.  
2.  Nowicki A., Lewandowski M., Wójcik J., Tymkiewicz R., LouMoller R.^{♦}, Wolny W.^{♦}, Zawada T.^{♦}, Thick Film Transducers for High Frequency Coded Ultrasonography, ARCHIVES OF ACOUSTICS, ISSN: 01375075, Vol.36, No.4, pp.945954, 2011 Streszczenie: Recently a new technology of piezoelectric transducers based on PZT thick film has been developed as a response to a call for devices working at higher frequencies suitable for production in large numbers at low cost. Eight PZT thick film based focused transducers with resonant frequency close to 40 MHz were fabricated and experimentally investigated. The PZT thick films were deposited on acoustically engineered ceramic substrates by pad printing. Considering high frequency and nonlinear propagation it has been decided to evaluate the axial pressure field emitted (and reflected by thick metal plate) by each of concave transducer differing in radius of curvature – 11 mm, 12 mm, 15 mm, 16 mm. Słowa kluczowe: transducers, thick film, high frequency ultrasound, pulse compression, Golay codes Afiliacje autorów:
 15p.  
3.  Secomski W., Nowicki A., Wójcik J., Lewandowski M., Walczak M., Tymkiewicz R., Annular array transducer and matched amplifier for therapeutic ultrasound, ARCHIVES OF ACOUSTICS, ISSN: 01375075, DOI: 10.2478/v1016801000496, Vol.35, No.4, pp.653660, 2010 Streszczenie: The use of therapeutic ultrasound continues to grow. A focused ultrasonic wave can increase the tissue temperature locally for the noninvasive cancer treatment or other medical applications. The authors have designed a sevenelement annular array transducer operating at 2.4 MHz. Each element was excited by sine burst supplied by a linear amplifier and FPGA control circuits. The acoustic field, generated by a transducer was initially numerically simulated in a computer and next compared to water tank hydrophone measurements performed at 20, 40 and 60 mm focal depth. The results showed good agreement of the measurements with theory and the possibility to focus the ultrasound in the preselected area. The total acoustic power radiated by the annular array was equal to 2.4W. Słowa kluczowe: ultrasonic therapy, annular array transducer, ultrasonic field Afiliacje autorów:
 9p.  
4.  Nowicki A., Trots I., Lewin P.A.^{♦}, Secomski W., Tymkiewicz R., Influence of the ultrasound transducer bandwidth on selection of the complementary Golay bit code length, Ultrasonics, ISSN: 0041624X, DOI: 10.1016/j.ultras.2007.07.003, Vol.47, pp.6473, 2007 Streszczenie: In contrast to previously published papers [A. Nowicki, Z. Klimonda, M. Lewandowski, J. Litniewski, P.A. Lewin, I. Trots, Comparison of sound fields generated by different coded excitations – Experimental results, Ultrasonics 44 (1) (2006) 121–129; J. Litniewski, A. Nowicki, Z. Klimonda, M. Lewandowski, Sound fields for coded excitations in water and tissue: experimental approach, Ultrasound Med. Biol. 33 (4) (2007) 601–607], which examined the factors influencing the spatial resolution of coded complementary Golay sequences (CGS), this paper investigates the effect of ultrasound imaging transducer’s fractional bandwidth on the gain of the compressed echo signal for different spectral widths of the CGS. Two different bit lengths were considered, specifically one and two cycles. Three transducers having fractional bandwidth of 25%, 58% and 80% and operating at frequencies 6, 4.4 and 6 MHz, respectively were examined (one of the 6 MHz sources was focused and made of composite material). The experimental results have shown that by increasing the code length, i.e. decreasing the bandwidth, the compressed echo amplitude could be enhanced. The smaller the bandwidth was the larger was the gain; the pulseecho sensitivity of the echo amplitude increased by 1.88, 1.62 and 1.47, for 25%, 58% and 80% bandwidths, respectively. These results indicate that two cycles bit length excitation is more suitable for use with bandwidth limited commercially available imaging transducers. Further, the time resolution is retained for transducers with two cycles excitation providing the fractional bandwidth is lower than approximately 90%. The results of this work also show that adjusting the code length allows signaltonoiseratio (SNR) to be enhanced while using limited (less that 80%) bandwidth imaging transducers. Also, for such bandwidth limited transducers two cycles excitation would not decrease the time resolution, obtained with ‘‘conventional’’ spike excitation. Hence, CGS excitation could be successfully implemented with the existing, relatively narrow band imaging transducers without the need to use usually more expensive wideband, composite ones. Słowa kluczowe: ultrasound imaging, transducer bandwidth, complementary Golay sequences Afiliacje autorów:
 
5.  Trots I., Nowicki A., Secomski W., Tymkiewicz R., The influence of the transducer bandwidth on the efficient Golay codes compression, ARCHIVES OF ACOUSTICS, ISSN: 01375075, Vol.32, No.4, pp.101110, 2007 Streszczenie: The maximization of penetration depth with concurrent retaining or enhancement of image resolution constitutes one of the time invariant challenges in ultrasound imaging. To solve this problem a pulse compression technique employing long coded sequences is now under intensive investigation and in fact some of the corresponding techniques were already implemented in commercial scanning machines. This paper investigates the influence of the effective bandwidth of the transducer on the behaviour of the encoding/compression technique and its potential influence on the axial resolution. We have investigated two different bits lengths – one and two periods – in the Golay sequences resulting in substantial difference of the bandwidth of the transmitted sequences. Three transducers with different fractional bandwidths were used in the experiments: 6 MHz focused transducer with 25% fractional bandwidth, 4.4 MHz flat transducer with 58% fractional bandwidth and 6 MHz flat, composite transducer with 80% fractional bandwidth. The experimental results are clearly showing that the elongation of the Golay single bit length (two cycles in our case) compensates for the limited transducer bandwidth. For 25% bandwidth peaktopeak echo increased by 1.89 times; for 58% bandwidth peaktopeak echo amplitude increased by 1.62 times, and for 80% bandwidth peaktopeak echo increased by 1.47 times. Słowa kluczowe: ultrasound imaging, transducer bandwidth, Golay complementary sequences Afiliacje autorów:
 
6.  Wójcik J., Powałowski T., Tymkiewicz R., Lamers A.^{♦}, Trawiński Z., Scattering of ultrasonic wave on a model of the artery, ARCHIVES OF ACOUSTICS, ISSN: 01375075, Vol.31, pp.471479, 2006 Streszczenie: The study was aimed at elaboration of a mathematical model to describe the process of acoustic wave propagation in an inhomogeneous and absorbing medium, whereas the wave is generated by an ultrasonic probe. The modelling proces covered the phenomenon of ultrasonic wave backscattering on an elastic pipe with dimensions similar to the artery section. Later on the numerical codes were determined in order to calculate the fields of ultrasonic waves, as well as backscattered fields for various boundary conditions. Numerical calculations make it possible to definethe waveforms for electric signals that are produced when ultrasonic waves, being reflected and backsvattered by an artery model, are then received by the ultrasonic probe. It is the signalwhich pretty well corresponds with the actual RF signal that is obtained during measurements at the output of anultrasonic apparatus. Słowa kluczowe: ultrasound, backscattering, artery, numerical model Afiliacje autorów:
 
7.  Nowicki A., Litniewski J., Secomski W., Trots I., Lewandowski M., Tymkiewicz R., Coded ultrasonography, Annual Report  Polish Academy of Sciences, ISSN: 16403754, pp.5657, 2005  
8.  Filipczyński L., Wójcik J., Kujawska T., Łypacewicz G.^{♦}, Tymkiewicz R., Zienkiewicz B., Nonlinear Native Propagation Effect of Diagnostic Ultrasound Computed and Measured in Blood, ULTRASOUND IN MEDICINE AND BIOLOGY, ISSN: 03015629, DOI: 10.1016/S03015629(00)00329X, Vol.27, No.2, pp.251257, 2001 Streszczenie: Nonlinear propagation effects produced by focused pulses in blood were measured over a 20cm range, being inspired by diagnostic applications in cardiology. The initial and maximum pressures applied during measurements in blood were equal to 0.40 MPapp and 0.76 MPapp, while the pressure estimated at the patient body surface equalled 0.70 MPapp. Measurements of the frequency characteristic and the linearity of the ultrasonic probe used in experiments were performed in water. A numerical procedure developed previously was applied in blood to calculate the pressure distribution of its first and second harmonics along the beam axis. The comparison of numerical and measured distributions in blood at a temperature of 37°C showed rather good agreement. Using numerical methods, a proportional growth of the second harmonic with the increased applied initial pressure was first observed, and finally the maximum limiting effect was found. In this way, much higher level of harmonics could be obtained. However, there arise the questions of the transmitting system construction and of the nonuniform resolution in the case of harmonic imaging when increasing the applied initial pressure. Słowa kluczowe: Ultrasound, Pulses, Nonlinear propagation, Blood, Cardiology Afiliacje autorów:
 
9.  Filipczyński L., Kujawska T., Tymkiewicz R., Wójcik J., Nonlinear and linear propagation of diagnostic ultrasound pulses, ULTRASOUND IN MEDICINE AND BIOLOGY, ISSN: 03015629, DOI: 10.1016/S03015629(98)001744, Vol.25, No.2, pp.285299, 1999 Streszczenie: The effect of nonlinear propagation in fluid followed by soft tissue was studied both theoretically and experimentally for a most crucial case in obstetrical ultrasonography. For this purpose, short pressure pulses, with the duration time of 1.3 μs and a carrier frequency of 3 MHz, radiated by a concave transducer into water, with maximum intensities up to the value of 18 W/cm2, were computed and measured. The ultrasonic beam had the physical focus at the distance of 6.5 cm, where the highest focal intensity of ISPPA= 242 W/cm2 was obtained. In front of the transducer, at a distance of 7 cm, artificial tissue samples prepared on the basis of ground porcine kidney, with a thickness of 0.5, 1.5 and 3 cm, were placed in water. Pressure pulses and their spectral components were produced numerically and measured by means of a PVDF hydrophone in water before and after penetrating the tissue samples. The theoretical analysis and measurements were carried out, in every case, for two signal levels: for a high level assuring nonlinear propagation and for a low one where conditions of linear propagation were fulfilled. In this way, it was possible to compare directly the effects of nonlinear and linear propagation, in every case showing a good conformity of theoretical values with measured ones. A method of determination of the effective frequency response of the hydrophone was elaborated to enable quantitative comparisons of numerical and experimental results. The theoretical part of our study was based on a paper of Wójcik (1998), enabling us to compute the characteristic function of nonlinear increase of absorption. An agreement of up to 10% was obtained when comparing theoretical and measured values of these functions in the investigated beam in water and behind tissue samples. The results obtained showed that the recently given theory of nonlinear absorption, based on the spectral analysis and the elaborated numerical procedures, may be useful in various practical ultrasonic medical problems and also in technological applications. Słowa kluczowe: Ultrasound, Pulses, Nonlinear propagation, Diagnostics Afiliacje autorów:
 
10.  Filipczyński L., Kujawska T., Tymkiewicz R., Wójcik J., Amplitude, isobar and gray scale imaging of ultrasonic shadows behind rigid, elastic and gaseous spheres, ULTRASOUND IN MEDICINE AND BIOLOGY, ISSN: 03015629, DOI: 10.1016/03015629(95)020314, Vol.22, No.2, pp.261270, 1996 Streszczenie: The theory of wave reflection from spherical obstacles was applied for determination of the cause of the shadow created by plane wave pulses incident on rigid, steel, gaseous spheres and on spheres made of kidney stones. The spheres were immersed in water which was assumed to be a tissuelike medium. Acoustic pressure distributions behind the spheres with the radii of 1 mm, 2.5 mm and 3.5 mm were determined at the frequency of 5 MHz. The use of the exact wave theory enabled us to take into account the diffraction effects. The computed pressure distributions were verified experimentally at the frequency of 5 MHz for a steel sphere with a 2.5mm radius. The experimental and theoretical pulses were composed of about three ultrasonic frequency periods. Acoustic pressure distributions in the shadow zone of all spheres were shown in the amplitude axonometric projection, in the grey scale and also as acoustic isobar patterns. Our analysis confirmed existing simpler descriptions of the shadow from the point of view of reflection and refraction effects; however, our approach is more general, also including diffraction effects and assuming the pulse mode. The analysis has shown that gaseous spherical inclusions caused shadows with very high dynamics of acoustic pressures that were about 15 dB higher in relation to all the other spheres. The shadow length, determined as the length at which one observes a 6dB drop of the acoustic pressure, followed the relation r−6dB = 3.7a2λ with the accuracy of about 20% independent of the sphere type. λ denotes the wavelength and a the sphere radius. Thus, a theoretical possibility of differentiating between gaseous and other inclusions and of estimation of the inclusion size in the millimeter range from the shadow was shown. The influence of the frequencydependent attenuation on the shadow will be considered in the next study. Słowa kluczowe: Shadow, Pulses, Spheres, Ultrasonography Afiliacje autorów:

Lista rozdziałów w ostatnich monografiach
1. 572  Doubrovina O.^{♦}, Tymkiewicz R., PiotrzkowskaWróblewska H., Gambin B., Aktualności Inżynierii Akustycznej i Biomedycznej, rozdział: Linking of structural parameters to properties of ultrasound backscattered signals by the threads phantoms study, Polskie Towarzystwo Akustyczne, Oddział w Krakowie, I, pp.6779, 2018  
2. 573  Gambin B., Kruglenko E., Litniewski J., Tymkiewicz R., Aktualności Inżynierii Akustycznej i Biomedycznej, rozdział: Dynamic elasticity, acoustical impedance and attenuation of special tissuelike phantoms, Polskie Towarzystwo Akustyczne, Oddział w Krakowie, I, pp.8996, 2018  
3. 494  Klimonda Z., DobruchSobczak K., PiotrzkowskaWróblewska H., Tymkiewicz R., Litniewski J., Postępy Akustyki 2016, rozdział: Obrazowanie tłumienia ultradźwięków w tkance nowotworowej, Polskie Towarzystwo Akustyczne, Oddział Warszawski, Warszawa, Poland, pp.3948, 2016  
4. 495  Litniewski J., Klimonda Z., Karwat P., PiotrzkowskaWróblewska H., DobruchSobczak K., Tymkiewicz R., Gambin B., Postępy Akustyki 2016, rozdział: Cancer malignancy sonic markers, Polskie Towarzystwo Akustyczne, Oddział Warszawski, Warszawa, Poland, pp.4960, 2016 
Prace konferencyjne
1.  Nowicki A., Gambin B., Trawiński Z., Secomski W., Szubielski M.^{♦}, Tymkiewicz R., Olszewski R., Radial Artery Reactive Response And Shear Rate Measurements Using 20 MHz System, IUS 2018, IEEE International Ultrasonics Symposium, 20181022/1025, KOBE (JP), pp.14, 2018 Streszczenie: The article attempts to select an ultrasound system to assess of endothelium dysfunctiondependent flow mediated dilation (FMD) and shear rate (SR) in radial artery after several minutes of hyperaemia. Methods: We compare the effective axial resolution and Doppler sensitivity of the standard US working below 12 MHz and high frequency (close to 20 MHz) scanning systems measuring the vessel diameter and blood flow measurements in radial arteries. FMD and FMD and SR were measured in Control group of 14 healthy volunteers, and in 13 with stable coronary artery diseases (CAD). Results: In a laboratory experiment of imaging two closely spaced food plastic foils, over three times better axial resolution was demonstrated for the 20 MHz ultrasound system in which the resolution was close to 0.1 mm. Also the sensitivity of the external single 20 MHz pulse Doppler transducer proved to be over 20 dB better (in terms of signaltonoise ratio) than the pulse Doppler incorporated into the L145 linear array. FMD in Control group was in the range of 8÷16% with mean±sd equal to 12.13 ± 2.34%; in CAD group FMD was in the range of 0.1÷7 % with mean±sd equal to 3.01±2.18% which was significantly less. FMD/SR was equal to 3.08 ± 1.34 × 10–4 in Control group and 1.01 ± 0.76 × 10–4 in CAD group with ranges equal to 1.66 ÷ 7.8× 10–4 and 0.4 ÷ 2.4× 10–4, respectively. Conclusions: Increasing scanning and Doppler mode frequency to 20 MHz improved the precision of FMD and SR measurements. Statistically significant differences between the two groups were confirmed by statistical tests for FMD and FMD/SR with pvalues < 0.05. The results obtained suggest the usefulness of the proposed ultrasonic system for measurements of FMD and SR in the radial artery to differentiate normal subjects from those with CAD. Słowa kluczowe: radial artery; shear rate; reactive hyperaemia; endothelium, pulsed Doppler Afiliacje autorów:
 
2.  Kruglenko E., Mizera A., Gambin B., Tymkiewicz R., Zienkiewicz B., Litniewski J., Nagrzewanie ultradźwiękami tkanek miękkich in vitro i własności akustyczne wytworzonych wzorców tkanek miękkich, 59th Open Seminar on Acoustics, 20120910/0914, Boszkowo (PL), pp.129132, 2012 Streszczenie: W pracy przedstawiono wstępne wyniki pomiaru pola temperatury wewnątrz tkanki in vitro w czasie procesu nagrzewania wiązką ultradźwiękową o słabej mocy oraz pomiaru właściwości akustycznych wzorców tkanek miękkich. Wzorce te zbudowano w celu dalszych badań nad powiązaniem wzrostu temperatury z właściwościami akustycznymi, gdyż próbki tkankowe in vitro okazały się niepowtarzalne i nietrwałe. Na wykonanych 3 wzorcach tkankowych dokonano pomiaru sygnału przejścia i wyznaczono prędkość propagacji impulsu, współczynnik tłumienia oraz zbadano statystykę rozproszenia. Przedyskutowano wpływ liczby elementów rozpraszających na te wielkości. Słowa kluczowe: wzorce tkanek, sygnał ultradźwiękowy, prędkość dźwięku, tłumienie, statystyka rozproszenia Afiliacje autorów:
 
3.  Litniewski J., Cieślik L., Lewandowski M., Tymkiewicz R., Zienkiewicz B., Nowicki A., Bone scanner for examination of deeply located trabecular bones, IUS 2011, IEEE International Ultrasonics Symposium, 20111018/1021, Orlando (US), DOI: 10.1109/ULTSYM.2011.0117, pp.486489, 2011 Streszczenie: The paper presents a new yield criterion for the transversal isotropy of metal sheets under planestress conditions which is an extension of the isotropic yield function proposed by Burzynski (Burzynski W. l928). Studium nad hipotezami Burzynski's doctoral dissertation "Study on material effort hypotheses”, Engng. Trans., 2009, t. 57, nr 34, s. l852l5). Two additional coefficients have been introduced in order to allow a better representation of plastic behavior of metal sheets. The proposed yield condition includes the influence of first invariant of the stress tensor and also the strength differential effect. The system of equations describing the sheet metal forming process is solved by algorithm using the return mapping procedure. PIane stress constraint is incorporated into the NewtonRaphson iteration loop. The proposed algorithm is verified by performing a numerical test using shell elements in commercial FEM software ABAQUS/EXPLICIT with a developed VUMAT subroutine. It is shown that the proposed approach provides the satisfactory prediction of material behavior, at least in the cases when anisotropy effects are not advanced. To perform FE simulations of cup deep drawing processes, three independent yield stresses are required. Those yield stresses can be obtained from: directional uniaxial tensile test, directional uniaxial compression test and equibiaxial compression tests. In the paper the formability of two metal sheets are analysed. First the influence of strength differential effect on the cup height profile is shown. Then the comparison between the HuberMisesHencky yield condition and the proposed yield condition is presented. Słowa kluczowe: bone scanner, trabecular bone, osteoporosis Afiliacje autorów:
 10p.  
4.  Nowicki A., Wójcik J., Lewandowski M., Tymkiewicz R., LouMoller R.^{♦}, Wolny W.^{♦}, Zawada T.^{♦}, Thick film transducers for high frequency coded ultrasonography, 9th International Conference on Information Technology and Applications in Biomedicine, 20091104/1107, Larnaka (CY), DOI: 10.1109/ITAB.2009.5394411, pp.14, 2009 Streszczenie: Recently a new technology of piezoelectric transducers based on PZT thick film has been developed as a response to a call for devices working at higher frequencies suitable for production in large numbers at low cost. Eight PZT thick film based focused transducers with resonant frequency close to 40 MHz were fabricated and experimentally investigated. The PZT thick films were deposited on acoustically engineered ceramic substrates by pad printing. Considering high frequency and nonlinear propagation it has been decided to evaluate the axial pressure field emitted (and reflected by thick metal plate) by each of concave transducer differing in radius of curvature  11 mm, 12 mm, 15 mm, 16 mm. Słowa kluczowe: transducers, thick film, high frequency ultrasound, pulse compression, Golay code Afiliacje autorów:
 10p. 
Abstrakty konferencyjne
1.  Kruglenko E., Tymkiewicz R., Litniewski J., Gambin B., Tissue Mimicking Materials in Ultrasonic Hyperthermia Study, AMADE2018, ANALYTICAL METHODS OF ANALYSIS AND DIFFERENTIAL EQUATIONS, Materials of the 9th International Workshop, 20180917/0921, Minsk (BY), No.1, pp.46, 2018  
2.  Doubrovina O.^{♦}, Tymkiewicz R., PiotrzkowskaWróblewska H., Gambin B., Linking of structural parameters to properties of ultrasound backscattered signals by the threads phantoms study, IAB2018, XXII Konferencja Inżynierii Akustycznej i Biomedycznej, 20180410/0413, KrakówZakopane (PL), No.1, pp.26, 2018 Streszczenie: The soft tissue structure possess the multiscale anatomical inhomogeneities. There Afiliacje autorów:
 
3.  Gambin B., Kruglenko E., Litniewski J., Tymkiewicz R., Ultrasonic Measurements of TissueLike Composite Materials Properties Applied to Quantify the Influence of Different Components on the Dynamic Elasticity, Acoustic Impedance and Ultrasound Absorption in This Materials, IAB2018, XXII Konferencja Inżynierii Akustycznej i Biomedycznej, 20180410/0413, KrakówZakopane (PL), No.1, pp.27, 2018 Streszczenie: We used 7 types of samples, ”pure agargel” sample (AG), agargel doped with graphite microparticles (GMP), agargel doped with magnetic microparticles (MMP) and agargel doped with magnetic nanoparticles (MNP) with every doping in two different proportion of ingredients, namely of weigh percentage of 0.8 and 1.6 of the added particles. In the series of experiments we registered RF echoes of backscattered signals emitted by singleelement transducer with focus posed on the metal reflector and in the focus posed inside the samples. From this data the speed of sound, the frequency dependent attenuation and backscatternig coefficient were obtained for every sample. Additionally, densities of sample materials were determined, and the elasticity coefficient and acoustical impedance of every material were calculated under the assumption of linear propagation. From the differences between attenuation and scattering the estimation of absorption were performed. The measurements demonstrated that adding the nanoparticles increased the density of the material compare to adding microparticles made from the same magnetic material. The elasticity coefficient and impedance are proportional to the fraction of particles and the elasticity of phantom components. The most interesting conclusion concerns in comparison of difference in ultrasonic absorption. The absorption of agargel with NMP exhibited the largest value in between all studied cases. This allows us to assume that the local heating of the medium by the ultrasonic beam should be more efficient in this case, and dopes of iron oxide nanoparticles can be considered as ”sonosensitizers” in performing ultrasonic hyperthermia. It is worth noting, that this result was independently confirmed by the measuring of temperature rise during the heating of phantoms by the focused ultrasound beams of different powers. This result is presented in another paper at this conference. Afiliacje autorów:
 
4.  Klimonda Z., DobruchSobczak K., PiotrzkowskaWróblewska H., Tymkiewicz R., Litniewski J., Ultrasound attenuation imaging of tumor tissue, OSA 16, LXIII Otwarte Seminarium z Akustyki, 20160913/0916, Białowieża (PL), DOI: 10.1515/aoa20160059, pp.619620, 2016 Słowa kluczowe: attenuation estimation, parametric imaging Afiliacje autorów:
 
5.  Litniewski J., Klimonda Z., Karwat P., PiotrzkowskaWróblewska H., DobruchSobczak K., Tymkiewicz R., Gambin B., Cancer Malignancy Sonic Markers, OSA 16, LXIII Otwarte Seminarium z Akustyki, 20160913/0916, Białowieża (PL), DOI: 10.1515/aoa20160059, No.3, pp.622, 2016 