Pub Date : 2013-06-23DOI: 10.1109/MSMW.2013.6622133
R. Golovashchenko
Study of liquids in a wide range of frequencies is the actual task for determination the change of their parameters. For this purpose, a number waveguide and resonant methods have been proposed [1]. In particular, solid-state dielectric resonators with partial filling them by liquid are used [2]. In this report the results of research the peculiarities of whispering gallery modes (WGM) in an axially symmetric liquid disk resonator, which resonator volume formed directly by liquid under test are presented [3] and its advantages for the study of the spatial distribution of the field of WGM as well for the measurement of small losses in nonpolar liquids are shown. Besides such resonance construction can simplify the investigation of the characteristics and processes in the resonator.
{"title":"Study and application of the liquid disk resonator in the millimeter waveband","authors":"R. Golovashchenko","doi":"10.1109/MSMW.2013.6622133","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622133","url":null,"abstract":"Study of liquids in a wide range of frequencies is the actual task for determination the change of their parameters. For this purpose, a number waveguide and resonant methods have been proposed [1]. In particular, solid-state dielectric resonators with partial filling them by liquid are used [2]. In this report the results of research the peculiarities of whispering gallery modes (WGM) in an axially symmetric liquid disk resonator, which resonator volume formed directly by liquid under test are presented [3] and its advantages for the study of the spatial distribution of the field of WGM as well for the measurement of small losses in nonpolar liquids are shown. Besides such resonance construction can simplify the investigation of the characteristics and processes in the resonator.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122898745","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622166
V. Skresanov, A. Barannik, N. Cherpak, Y. He, V. Glamazdin, V. Zolotaryov, A. Shubny, L. Sun, J. Wang, Y. Wu
This paper presents the results of the design and testing of seven-pole BPF Ka band with bilateral HTS insert in the E-plane rectangular waveguide. Study of the possibility of reducing the insertion loss in the E-plane filters with HTS inserts compared with losses in the filters with normal metal inserts is a purpose of the work. HTS insert is a single crystal MgO substrate of 0.5 mm thickness, of which the two surfaces are coated with superconducting YBCO films. By photolithography method, identical insert portions of the superconducting layers were removed on both sides of a substrate and thereby "window” chains were formed with a height equal to the height of the standard rectangular waveguide of 7.2x3.4 mm2 section. The lengths of all "windows" and the distance between them along the axis OZ were calculated as a result of designing the filter. Therefore, individual resonators of seven-pole BPF are rectangular waveguide sections with dielectric MgO plates in the E-plane. The mutual coupling between the resonators and the coupling of the first and the last resonators with matched waveguide are carried out by means of pairs of the below-cutoff waveguide sections formed by the original walls of the waveguide and the conducting YBCO layers. It is clear that the principle of operation of the filter with HTS insert analogous to the principle of BPF widely used in practice with normal metal E-plane inserts.
{"title":"Experience in developing Ka-band waveguide filter with HTS E-plane insert","authors":"V. Skresanov, A. Barannik, N. Cherpak, Y. He, V. Glamazdin, V. Zolotaryov, A. Shubny, L. Sun, J. Wang, Y. Wu","doi":"10.1109/MSMW.2013.6622166","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622166","url":null,"abstract":"This paper presents the results of the design and testing of seven-pole BPF Ka band with bilateral HTS insert in the E-plane rectangular waveguide. Study of the possibility of reducing the insertion loss in the E-plane filters with HTS inserts compared with losses in the filters with normal metal inserts is a purpose of the work. HTS insert is a single crystal MgO substrate of 0.5 mm thickness, of which the two surfaces are coated with superconducting YBCO films. By photolithography method, identical insert portions of the superconducting layers were removed on both sides of a substrate and thereby \"window” chains were formed with a height equal to the height of the standard rectangular waveguide of 7.2x3.4 mm2 section. The lengths of all \"windows\" and the distance between them along the axis OZ were calculated as a result of designing the filter. Therefore, individual resonators of seven-pole BPF are rectangular waveguide sections with dielectric MgO plates in the E-plane. The mutual coupling between the resonators and the coupling of the first and the last resonators with matched waveguide are carried out by means of pairs of the below-cutoff waveguide sections formed by the original walls of the waveguide and the conducting YBCO layers. It is clear that the principle of operation of the filter with HTS insert analogous to the principle of BPF widely used in practice with normal metal E-plane inserts.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124983021","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6621990
T. Idehara, S. Sabchevski
Powerful sources of coherent radiation in the sub-terahertz to terahertz frequency range are required for expanding number of applications in the physical research and in various advanced high power THz technologies. In recent years, a spectacular progress in the development of various gyro-devices and in particular, the powerful high frequency (sub-terahertz to terahertz) gyrotron oscillators has demonstrated a remarkable potential for bridging the so-called terahertz power gap and stimulated many novel and prospective applications. In this paper, we outline two series of such gyro-devices, namely the Gyrotron FU Series which includes pulsed gyrotrons and Gyrotron FU CW Series which consist of CW (continuous wave) or long pulse gurotrons. Both series are developed at Research Center for Development of Far Infrared Region, University of Fukui (FIR FU). We present the most remarkable achievements of these devices and illustrate their applications by some characteristic examples. An outlook for the further extension of the Gyrotron FU CW Series is also provided.
{"title":"Development of high frequency Gyrotrons in FIR FU covering sub-THz to THz range for applications to high power THz spectroscopy","authors":"T. Idehara, S. Sabchevski","doi":"10.1109/MSMW.2013.6621990","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6621990","url":null,"abstract":"Powerful sources of coherent radiation in the sub-terahertz to terahertz frequency range are required for expanding number of applications in the physical research and in various advanced high power THz technologies. In recent years, a spectacular progress in the development of various gyro-devices and in particular, the powerful high frequency (sub-terahertz to terahertz) gyrotron oscillators has demonstrated a remarkable potential for bridging the so-called terahertz power gap and stimulated many novel and prospective applications. In this paper, we outline two series of such gyro-devices, namely the Gyrotron FU Series which includes pulsed gyrotrons and Gyrotron FU CW Series which consist of CW (continuous wave) or long pulse gurotrons. Both series are developed at Research Center for Development of Far Infrared Region, University of Fukui (FIR FU). We present the most remarkable achievements of these devices and illustrate their applications by some characteristic examples. An outlook for the further extension of the Gyrotron FU CW Series is also provided.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125084316","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622141
Yulia S. Dementieva
In this paper we present mathematical model and numerical algorithm allowing investigating two-dimensional and three-dimensional photonic crystals and waveguiding systems based on photonic crystals. We demonstrate spectral characteristic of photonic crystals and systems based on them.
{"title":"Mathematical modeling of waveguiding systems based on photonic crystals","authors":"Yulia S. Dementieva","doi":"10.1109/MSMW.2013.6622141","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622141","url":null,"abstract":"In this paper we present mathematical model and numerical algorithm allowing investigating two-dimensional and three-dimensional photonic crystals and waveguiding systems based on photonic crystals. We demonstrate spectral characteristic of photonic crystals and systems based on them.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121344698","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622082
A. Kirilenko, D. Kulik, S. Prikolotin, L. Rud, S. Steshenko
The attention to coaxial waveguide polarizers is caused due to developing multifrequency antenna systems, e.g. for radio telescopes, operating over two or more sufficiently spaced frequency bands. If the inner conductor is hollow and acts as a conventional circular waveguide, it can be used for transmitting a higher-frequency signal while the coaxial region provides the lower-frequency signal propagation. The further addition of outer cylindrical conductors allows increasing a corresponding number of frequency bands.
{"title":"Design and optimization of broadband ridged coaxial waveguide polarizers","authors":"A. Kirilenko, D. Kulik, S. Prikolotin, L. Rud, S. Steshenko","doi":"10.1109/MSMW.2013.6622082","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622082","url":null,"abstract":"The attention to coaxial waveguide polarizers is caused due to developing multifrequency antenna systems, e.g. for radio telescopes, operating over two or more sufficiently spaced frequency bands. If the inner conductor is hollow and acts as a conventional circular waveguide, it can be used for transmitting a higher-frequency signal while the coaxial region provides the lower-frequency signal propagation. The further addition of outer cylindrical conductors allows increasing a corresponding number of frequency bands.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125302912","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622109
V. Ryskin, A. Shvetsov, V. M. Demkin, L. Kukin, L. Fedoseev, A. M. Shchitov
Studying of thermal balance of terrestrial atmosphere is substantially connected with results of measurements of tropospheric and stratospheric temperature profile. Now in the Russian Federation the system of quasi continuous monitoring of thermodynamic characteristics of atmosphere is carried out thanks to discrete start-up of radiosondes, their top working border seldom reaches stratospheric heights. However, continuous aerologic sounding may be realized by means of the remote methods using microwave atmosphere thermal radiation. Particularly, presence of strong lines and band of molecular oxygen in the atmospheric millimeter wave radiation spectrum make it possible to use them for thermal sounding from ground up to stratopause. For measurement of troposphere temperature profile in Institute of Applied Physics Russian Academy of Sciences 8-channel spectroradiometer is developed. It operates in a frequency range of 50-55 GHz which corresponds to a low-frequency slope of a 5-millimeter wave-band of molecular oxygen spectrum. The device represents heterodyne receiver with low-noise HEMT front end amplifier (LNA). The amplifier has in a working wave-band a gain about of 16 dB and a noise figure no more than 4 dB. The following LNA Shottky diode mixer works on the first harmonic of a local oscillator signal (fLO = 48 GHz) and converts RF input signal to the 2 - 7 GHz intermediate frequency band (IF). Conversion loss of the mixer is 8-10 dB. Local oscillator signal (48 GHz) is formed by means of a signal synthesizer (8 GHz) having output power of 50 mW by multipliers and band-pass filters circuit. Power level of local oscillator signal 48 GHz on a mixer input is not less than 10 mW with suppression of harmful frequencies not less than 50 dB.
{"title":"Ground-based microwave spectroradiometer for thermal sounding of atmosphere","authors":"V. Ryskin, A. Shvetsov, V. M. Demkin, L. Kukin, L. Fedoseev, A. M. Shchitov","doi":"10.1109/MSMW.2013.6622109","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622109","url":null,"abstract":"Studying of thermal balance of terrestrial atmosphere is substantially connected with results of measurements of tropospheric and stratospheric temperature profile. Now in the Russian Federation the system of quasi continuous monitoring of thermodynamic characteristics of atmosphere is carried out thanks to discrete start-up of radiosondes, their top working border seldom reaches stratospheric heights. However, continuous aerologic sounding may be realized by means of the remote methods using microwave atmosphere thermal radiation. Particularly, presence of strong lines and band of molecular oxygen in the atmospheric millimeter wave radiation spectrum make it possible to use them for thermal sounding from ground up to stratopause. For measurement of troposphere temperature profile in Institute of Applied Physics Russian Academy of Sciences 8-channel spectroradiometer is developed. It operates in a frequency range of 50-55 GHz which corresponds to a low-frequency slope of a 5-millimeter wave-band of molecular oxygen spectrum. The device represents heterodyne receiver with low-noise HEMT front end amplifier (LNA). The amplifier has in a working wave-band a gain about of 16 dB and a noise figure no more than 4 dB. The following LNA Shottky diode mixer works on the first harmonic of a local oscillator signal (fLO = 48 GHz) and converts RF input signal to the 2 - 7 GHz intermediate frequency band (IF). Conversion loss of the mixer is 8-10 dB. Local oscillator signal (48 GHz) is formed by means of a signal synthesizer (8 GHz) having output power of 50 mW by multipliers and band-pass filters circuit. Power level of local oscillator signal 48 GHz on a mixer input is not less than 10 mW with suppression of harmful frequencies not less than 50 dB.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126424261","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622017
Jhuo-Ro Li, C. Chiu, C. Chuang
In this paper, we propose a method, which combines a particle swarm optimization (PSO) algorithm with a Newton-Kantorovitch algorithm for image reconstruction of perfectly conducting objects. First, the inverse problem is recast as a global nonlinear optimization problem, which is solved by a PSO. Then, the solution obtained by the PSO is taken as an initial guess for the Newton-Kantorovitch algorithm to obtain the more accuracy solution in a few iterations. Numerical simulations are conducted to demonstrate that our cascaded method is accurate and practical. Numerical results show that the performance of this cascaded method is better than the individual PSO and the individual Newton-Kantorovitch algorithm. Satisfactory reconstruction has been obtained by using this cascaded method.
{"title":"Application of cascaded methods for inverse problem","authors":"Jhuo-Ro Li, C. Chiu, C. Chuang","doi":"10.1109/MSMW.2013.6622017","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622017","url":null,"abstract":"In this paper, we propose a method, which combines a particle swarm optimization (PSO) algorithm with a Newton-Kantorovitch algorithm for image reconstruction of perfectly conducting objects. First, the inverse problem is recast as a global nonlinear optimization problem, which is solved by a PSO. Then, the solution obtained by the PSO is taken as an initial guess for the Newton-Kantorovitch algorithm to obtain the more accuracy solution in a few iterations. Numerical simulations are conducted to demonstrate that our cascaded method is accurate and practical. Numerical results show that the performance of this cascaded method is better than the individual PSO and the individual Newton-Kantorovitch algorithm. Satisfactory reconstruction has been obtained by using this cascaded method.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126519556","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622034
A. Arkhipov, K. Vytovtov
Optimization method for anisotropic layered structure synthesis is proposed. The method is based on a Monte-Carlo optimization algorithm and a numerical second-order optimization methods. The frequency-divided filter is calculated as the result. Obtained filter is discussed and practical application is proposed.
{"title":"Method of the parameters optimization for terahertz anisotropic layered filter","authors":"A. Arkhipov, K. Vytovtov","doi":"10.1109/MSMW.2013.6622034","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622034","url":null,"abstract":"Optimization method for anisotropic layered structure synthesis is proposed. The method is based on a Monte-Carlo optimization algorithm and a numerical second-order optimization methods. The frequency-divided filter is calculated as the result. Obtained filter is discussed and practical application is proposed.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127803265","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622074
V. Shcherbak
Acquired earlier experience of an optimization of the TE-waves converters we use for creation of TM-waves converters in flat (rectangular) waveguides, which are more interesting to usage in an electronics. We also optimize interaction of the TEM-wave with higher of TE- and TM-waves to create converters on the basis of the cascade from three unequally-period gratings in free-space. However there were difficulties of providing flat-topped (and from this broadband ) amplitude-frequency response of converters on TM- and TEM-waves. The search of modified constructions of such devices for overcoming these difficulties is necessary.
{"title":"Conversion of tem-wave in higher waves on the cascades from three unequally-period diaphragms or gratings","authors":"V. Shcherbak","doi":"10.1109/MSMW.2013.6622074","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622074","url":null,"abstract":"Acquired earlier experience of an optimization of the TE-waves converters we use for creation of TM-waves converters in flat (rectangular) waveguides, which are more interesting to usage in an electronics. We also optimize interaction of the TEM-wave with higher of TE- and TM-waves to create converters on the basis of the cascade from three unequally-period gratings in free-space. However there were difficulties of providing flat-topped (and from this broadband ) amplitude-frequency response of converters on TM- and TEM-waves. The search of modified constructions of such devices for overcoming these difficulties is necessary.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"4 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129034151","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 : 2013-06-23DOI: 10.1109/MSMW.2013.6622159
V. Kravchenko, D. Churikov
On the basis of the atomic functions ha(t) the Kravchenko-Kotelnikov interpolation series for restoration of correlation functions in problems of stochastic processes modeling is offered.
{"title":"Correlation functions interpolation by generalized Kravchenko-Kotelnikov sampling series","authors":"V. Kravchenko, D. Churikov","doi":"10.1109/MSMW.2013.6622159","DOIUrl":"https://doi.org/10.1109/MSMW.2013.6622159","url":null,"abstract":"On the basis of the atomic functions ha(t) the Kravchenko-Kotelnikov interpolation series for restoration of correlation functions in problems of stochastic processes modeling is offered.","PeriodicalId":104362,"journal":{"name":"2013 International Kharkov Symposium on Physics and Engineering of Microwaves, Millimeter and Submillimeter Waves","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127351770","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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