Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546013
O. Morozov, P. Hunziker
We present a tensor based approach for the efficient reconstruction of high-dimensional signals from large sets of irregularly sampled measurements. Using our tensor framework we analyzed the structure of the B-spline reconstruction problem and identified its important tensor properties, which were used for building a computationally and memory efficient solving algorithm. The proposed algorithm was successfully validated on 3D/4D standard datasets, where this novel tensor-based algorithm outperformed existing spline approaches. Then the algorithm was applied to a large practical problem of reconstruction of 4D medical ultrasound signal from irregularly sampled data.
{"title":"Tensor B-spline reconstruction of multidimensional signals from large irregularly sampled data","authors":"O. Morozov, P. Hunziker","doi":"10.1109/MSMW.2010.5546013","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546013","url":null,"abstract":"We present a tensor based approach for the efficient reconstruction of high-dimensional signals from large sets of irregularly sampled measurements. Using our tensor framework we analyzed the structure of the B-spline reconstruction problem and identified its important tensor properties, which were used for building a computationally and memory efficient solving algorithm. The proposed algorithm was successfully validated on 3D/4D standard datasets, where this novel tensor-based algorithm outperformed existing spline approaches. Then the algorithm was applied to a large practical problem of reconstruction of 4D medical ultrasound signal from irregularly sampled data.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122503966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546028
S. Baranov
Microwave engineering is of great importance in a wide spectrum of applications most of them related to wireless telecommunications systems, as in telephone, broadcast satellite television, or in satellite global positioning.
微波工程在广泛的应用中非常重要，其中大多数与无线通信系统有关，如电话、广播卫星电视或卫星全球定位。
{"title":"Highfrequency properties of amorphous microwires","authors":"S. Baranov","doi":"10.1109/MSMW.2010.5546028","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546028","url":null,"abstract":"Microwave engineering is of great importance in a wide spectrum of applications most of them related to wireless telecommunications systems, as in telephone, broadcast satellite television, or in satellite global positioning.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121573740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546073
D. But, O. Golenkov
There is an increased interest in the use of terahertz (THz) radiation (frequency range 0.1-10 THz) for various applications in the fields of security screening, medicine, radio astronomy, etc. Nowadays main concepts of THz radiation detection are well-studied which allowed to create such types of THz receivers as low temperature quasiparticle detectors, Schottky diodes, micro-bolometers, MOSFET and HEMT-detectors, etc [1].
{"title":"Current sensivity of Si mosfet to terahertz irradiation","authors":"D. But, O. Golenkov","doi":"10.1109/MSMW.2010.5546073","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546073","url":null,"abstract":"There is an increased interest in the use of terahertz (THz) radiation (frequency range 0.1-10 THz) for various applications in the fields of security screening, medicine, radio astronomy, etc. Nowadays main concepts of THz radiation detection are well-studied which allowed to create such types of THz receivers as low temperature quasiparticle detectors, Schottky diodes, micro-bolometers, MOSFET and HEMT-detectors, etc [1].","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130307862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546083
G. Glibitskiy
The research of change of viscosity and dielectric properties of solutions at various temperatures and concentration allows to characterise the structural and power changes bound to interaction of molecules of a dissolvent and dissolved substance in a solution (1–3). The saccharose solutions have been chosen for researches as their dielectric properties on low frequencies well known (4). For measurement of viscosity Ostvald's viscosimeter was used (5). Viscosity of a solution was defined from: η = η0dt/d0t0 where η0 is viscosity of a dissolvent, d and d0 is solution and dissolvent densities, t and t0 - course time of a solution and dissolvent through capillary.
{"title":"Energy of activation of saccharose in solutions","authors":"G. Glibitskiy","doi":"10.1109/MSMW.2010.5546083","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546083","url":null,"abstract":"The research of change of viscosity and dielectric properties of solutions at various temperatures and concentration allows to characterise the structural and power changes bound to interaction of molecules of a dissolvent and dissolved substance in a solution (1–3). The saccharose solutions have been chosen for researches as their dielectric properties on low frequencies well known (4). For measurement of viscosity Ostvald's viscosimeter was used (5). Viscosity of a solution was defined from: η = η<inf>0</inf>dt/d<inf>0</inf>t<inf>0</inf> where η<inf>0</inf> is viscosity of a dissolvent, d and d<inf>0</inf> is solution and dissolvent densities, t and t<inf>0</inf> - course time of a solution and dissolvent through capillary.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"8 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114146155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546054
V. Shcherbinin, G. Zaginaylov
Nowadays coaxial cavity gyrotrons are very promising sources of millimeter wave radiation which can be successfully used in thermonuclear fusion and some other applications. Development of industrial prototype of coaxial cavity gyrotron is in progress. One of the main obstacles in the enhancement of gyrotron performances is mode competition, which appears due to high density of mode spectrum in MW-class gyrotrons. Usually before reaching the operational point with maximal efficiency in the desired mode the accelerating voltage increases in time from zero value (start-up scenario). During start-up different cavity modes can be excited. In the last experiments the operational TE34,19 mode was excited stably over a wide range of the accelerating voltage (67 – 90kV) and has achieved the maximal output power of 1.8 MW near the upper boundary of the excitation region (∼90kV) [1]. At the higher voltage the efficiency of excitation for the operational mode sharply dropped and the multi-wave generation regime was sustained. However, in numerical simulations performed by our code [2] and the code SELFT [3] the excitation region is notably wider (up to the accelerating voltage ∼ 97 kV according to our results). The predicted maximal output power can achieve ∼ 2.5 MW. The discrepancy between experimental measurements and simulation results were attributed to the mode competition, however including several of the most dangerous competing modes into simulation did not lead to the more consistent results. One of the possible mechanisms of the oscillation range decreasing for the operational gyrotron mode was proposed in [4]. According to [4] excitation of the radial satellites of the operational mode (TE34,18, TE34,20) can shift the upper boundary of oscillation region for the TE34,19 mode and thereby reduces its power. However simulations performed by our code did not confirmed the results obtained in [4]. Moreover, we can propose another mechanism of the reduced output power observed in the experiments.
{"title":"Some peculiarities of hard excitation regime in 2 MW 170 GHZ CW coaxial gyrotron for iter","authors":"V. Shcherbinin, G. Zaginaylov","doi":"10.1109/MSMW.2010.5546054","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546054","url":null,"abstract":"Nowadays coaxial cavity gyrotrons are very promising sources of millimeter wave radiation which can be successfully used in thermonuclear fusion and some other applications. Development of industrial prototype of coaxial cavity gyrotron is in progress. One of the main obstacles in the enhancement of gyrotron performances is mode competition, which appears due to high density of mode spectrum in MW-class gyrotrons. Usually before reaching the operational point with maximal efficiency in the desired mode the accelerating voltage increases in time from zero value (start-up scenario). During start-up different cavity modes can be excited. In the last experiments the operational TE34,19 mode was excited stably over a wide range of the accelerating voltage (67 – 90kV) and has achieved the maximal output power of 1.8 MW near the upper boundary of the excitation region (∼90kV) [1]. At the higher voltage the efficiency of excitation for the operational mode sharply dropped and the multi-wave generation regime was sustained. However, in numerical simulations performed by our code [2] and the code SELFT [3] the excitation region is notably wider (up to the accelerating voltage ∼ 97 kV according to our results). The predicted maximal output power can achieve ∼ 2.5 MW. The discrepancy between experimental measurements and simulation results were attributed to the mode competition, however including several of the most dangerous competing modes into simulation did not lead to the more consistent results. One of the possible mechanisms of the oscillation range decreasing for the operational gyrotron mode was proposed in [4]. According to [4] excitation of the radial satellites of the operational mode (TE34,18, TE34,20) can shift the upper boundary of oscillation region for the TE34,19 mode and thereby reduces its power. However simulations performed by our code did not confirmed the results obtained in [4]. Moreover, we can propose another mechanism of the reduced output power observed in the experiments.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114753660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546171
O. Prokopenko, O. Vakaliuk, K. Greben, A. Kalenyuk, V. Pan
An original variant of high-temperature superconductor (HTS) film impedance determination using combined microstrip resonator (MSR) is presented. The significant advantage of the method is a possibility of HTS film properties investigation in applied external magnetic field. The general review of HTS film impedance determination has been made. The theoretical analysis of combined MSR has been carried out using Bubnov - Galerkin - Ritz method (modified momentum method) and the geometry factor of combined MSR has been estimated. The method application for the HTS film properties investigation in an applied external magnetic field is illustrated.
{"title":"HTS film characterization using combined microstrip resonator","authors":"O. Prokopenko, O. Vakaliuk, K. Greben, A. Kalenyuk, V. Pan","doi":"10.1109/MSMW.2010.5546171","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546171","url":null,"abstract":"An original variant of high-temperature superconductor (HTS) film impedance determination using combined microstrip resonator (MSR) is presented. The significant advantage of the method is a possibility of HTS film properties investigation in applied external magnetic field. The general review of HTS film impedance determination has been made. The theoretical analysis of combined MSR has been carried out using Bubnov - Galerkin - Ritz method (modified momentum method) and the geometry factor of combined MSR has been estimated. The method application for the HTS film properties investigation in an applied external magnetic field is illustrated.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116308334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546097
I. Lapkin, V. Belitsky, I. Zinchenko
The goal of this project is to build a 3 mm SIS multi-beam (matrix) receiver for the 22-m radio telescope of the Crimean Astrophysical observatory. This project was launched in collaboration with Group for Advanced Receiver Development (GARD), Chalmers University (Sweden). The receiver employs compact DSB SIS mixers, designed by GARD for matrix receiver applications (Fig. 1). It shows good stability and provides receiver DSB noise temperature better than 50K in the frequency range 85–110 GHz. Broadband impedance transformation of the SIS junction allows covering working frequency band with a fixed backshort position.
{"title":"Matrix 4-element sis receiver of the 3mm wavelength range for the RT-22 telescope","authors":"I. Lapkin, V. Belitsky, I. Zinchenko","doi":"10.1109/MSMW.2010.5546097","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546097","url":null,"abstract":"The goal of this project is to build a 3 mm SIS multi-beam (matrix) receiver for the 22-m radio telescope of the Crimean Astrophysical observatory. This project was launched in collaboration with Group for Advanced Receiver Development (GARD), Chalmers University (Sweden). The receiver employs compact DSB SIS mixers, designed by GARD for matrix receiver applications (Fig. 1). It shows good stability and provides receiver DSB noise temperature better than 50K in the frequency range 85–110 GHz. Broadband impedance transformation of the SIS junction allows covering working frequency band with a fixed backshort position.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116456061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546152
V. Sugak, A. Sugak
One of the problems hindering wider use of GPR radar sensing is the estimation of the physical properties of objects and soil layers directly on the results of sensing. Usually the result of the sensing is a brightness image of the soil profile along the georadar movement, which does not allow making conclusions about the physical properties of the environment or the individual objects observed on this image. Such conclusions can only be made in case of assessment of the frequency dependence of attenuation per unit length or the phase velocity of radio waves propagation in the layers of the soil. This information can be extracted using a Stepped Frequency Continuous Wave (SFCW) radar signal [1]. In this case, these relationships can be evaluated using quadrature signals at the output of georadar receiver phase detector, as their phase structure at each frequency step contains the necessary information.
{"title":"GPR signal phase structure aplication for estimation of distribution of soil electrical properties on depth","authors":"V. Sugak, A. Sugak","doi":"10.1109/MSMW.2010.5546152","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546152","url":null,"abstract":"One of the problems hindering wider use of GPR radar sensing is the estimation of the physical properties of objects and soil layers directly on the results of sensing. Usually the result of the sensing is a brightness image of the soil profile along the georadar movement, which does not allow making conclusions about the physical properties of the environment or the individual objects observed on this image. Such conclusions can only be made in case of assessment of the frequency dependence of attenuation per unit length or the phase velocity of radio waves propagation in the layers of the soil. This information can be extracted using a Stepped Frequency Continuous Wave (SFCW) radar signal [1]. In this case, these relationships can be evaluated using quadrature signals at the output of georadar receiver phase detector, as their phase structure at each frequency step contains the necessary information.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116695979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546114
V. Frolov
In the report we present some results recently obtained in experiments carried out at the Sura heating facility (Russia; coordinates: 56.15 N, 46.13 E). They are related to studying features of artificial ionosphere turbulence (AIT) excited in the ionospheric plasma, which is modified by O-mode powerful radio waves.
在报告中，我们介绍了最近在苏拉加热设施(俄罗斯;坐标:56.15 N, 46.13 E)。它们与研究在电离层等离子体中激发的人工电离层湍流(AIT)的特征有关，该等离子体由o型强无线电波修饰。
{"title":"Some features of artificial ionosphere turbulence excited by the Sura heating facility","authors":"V. Frolov","doi":"10.1109/MSMW.2010.5546114","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546114","url":null,"abstract":"In the report we present some results recently obtained in experiments carried out at the Sura heating facility (Russia; coordinates: 56.15 N, 46.13 E). They are related to studying features of artificial ionosphere turbulence (AIT) excited in the ionospheric plasma, which is modified by O-mode powerful radio waves.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"653 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132052910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-06-21DOI: 10.1109/MSMW.2010.5546161
M. Uss, B. Vozel, K. Chehdi, V. Lukin, S. Abramov
In this paper, we dealt with the problem of noise variance estimation from additive mixture of the noise and an underlying image texture. Assuming fBm-model for image texture, the number Me(H,SNR)of SWs has been obtained such that statistical efficiency e of the previously designed ML noise variance estimator is close to a predefined level e = 0.9. The value Me defines a boundary between asymptotic and non-asymptotic modes of the ML estimator with respect to image fragment size (number of SWs available). For fixed SNR, Me takes minimum values for smooth textures ( H close to 0.8) and increases fast as H approaches 0. As a function of SNR, Me has minimum at approximately SNR = 1.5 and increases fast as SNR deviates from this value. These results are useful for establishing the area of applicability of noise variance estimators and to assure the quality of estimates obtained from an image texture of a given size, roughness and SNR.
{"title":"The minimum number of scanning windows required for effective maximum likelihood estimation of image texture parameters and additive noise variance","authors":"M. Uss, B. Vozel, K. Chehdi, V. Lukin, S. Abramov","doi":"10.1109/MSMW.2010.5546161","DOIUrl":"https://doi.org/10.1109/MSMW.2010.5546161","url":null,"abstract":"In this paper, we dealt with the problem of noise variance estimation from additive mixture of the noise and an underlying image texture. Assuming fBm-model for image texture, the number Me(H,SNR)of SWs has been obtained such that statistical efficiency e of the previously designed ML noise variance estimator is close to a predefined level e = 0.9. The value Me defines a boundary between asymptotic and non-asymptotic modes of the ML estimator with respect to image fragment size (number of SWs available). For fixed SNR, Me takes minimum values for smooth textures ( H close to 0.8) and increases fast as H approaches 0. As a function of SNR, Me has minimum at approximately SNR = 1.5 and increases fast as SNR deviates from this value. These results are useful for establishing the area of applicability of noise variance estimators and to assure the quality of estimates obtained from an image texture of a given size, roughness and SNR.","PeriodicalId":129834,"journal":{"name":"2010 INTERNATIONAL KHARKOV SYMPOSIUM ON PHYSICS AND ENGINEERING OF MICROWAVES, MILLIMETER AND SUBMILLIMETER WAVES","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128679752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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