Pub Date : 2012-12-01DOI: 10.23919/EUMC.2012.6459266
Se-Young Hyun, Kyung-Won Lee, J. Yook
In this paper, the shielding effectiveness of reinforced concrete structures under electromagnetic pulse (EMP) illumination has been modeled and analyzed below 1 GHz regime. The reinforced concrete provides shielding effectiveness at particular frequencies by the concrete as well as the embedded reinforced conductive grid. The reinforced concrete structures are analyzed using commercial 3-dimensional electromagnetic field solver. The shielding effectiveness has been accessed by computing the effect of concrete, rebar and entire reinforced concrete. These results suggest that decreasing spacing of the rebar and increasing the rebar diameter will decrease transmission coefficient. The single layer having the thickness of rebar of 10, 20 and 30 mm reveal transmission coefficient of -1.89, -2.73 and -4.76 dB/10cm, respectively, at 500 MHz. In addition, double layers rebar structure provides -2.46, -6.16 and -9.55 dB/10cm attenuation, respectively, for the same conditions.
{"title":"Modeling of shielding effectiveness of reinforced concrete walls for electromagnetic pulse","authors":"Se-Young Hyun, Kyung-Won Lee, J. Yook","doi":"10.23919/EUMC.2012.6459266","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459266","url":null,"abstract":"In this paper, the shielding effectiveness of reinforced concrete structures under electromagnetic pulse (EMP) illumination has been modeled and analyzed below 1 GHz regime. The reinforced concrete provides shielding effectiveness at particular frequencies by the concrete as well as the embedded reinforced conductive grid. The reinforced concrete structures are analyzed using commercial 3-dimensional electromagnetic field solver. The shielding effectiveness has been accessed by computing the effect of concrete, rebar and entire reinforced concrete. These results suggest that decreasing spacing of the rebar and increasing the rebar diameter will decrease transmission coefficient. The single layer having the thickness of rebar of 10, 20 and 30 mm reveal transmission coefficient of -1.89, -2.73 and -4.76 dB/10cm, respectively, at 500 MHz. In addition, double layers rebar structure provides -2.46, -6.16 and -9.55 dB/10cm attenuation, respectively, for the same conditions.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129230443","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 : 2012-12-01DOI: 10.23919/EUMC.2012.6459252
E. Janssen, D. Milosevic, P. Baltus, A. V. van Roermund, H. Habibi
In this paper an approach is proposed for the suppression of a large unwanted signal without making use of frequency selectivity, but rather by exploiting a nonlinear transfer function. The general requirements for large-signal suppression by this technique are analyzed in the context of a multi-standard transceiver. Also the consequences for weak desired signals and external interference are being discussed. The IIP3 for external interference is derived, and consequences for the noise performance. The proposed technique shows a good IIP3 performance, but comes with a penalty of increasing the output noise by 3dB because of the spectrum mirroring that takes place.
{"title":"Frequency-independent smart interference suppression for multi-standard transceivers","authors":"E. Janssen, D. Milosevic, P. Baltus, A. V. van Roermund, H. Habibi","doi":"10.23919/EUMC.2012.6459252","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459252","url":null,"abstract":"In this paper an approach is proposed for the suppression of a large unwanted signal without making use of frequency selectivity, but rather by exploiting a nonlinear transfer function. The general requirements for large-signal suppression by this technique are analyzed in the context of a multi-standard transceiver. Also the consequences for weak desired signals and external interference are being discussed. The IIP3 for external interference is derived, and consequences for the noise performance. The proposed technique shows a good IIP3 performance, but comes with a penalty of increasing the output noise by 3dB because of the spectrum mirroring that takes place.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117140016","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 : 2012-12-01DOI: 10.23919/EUMC.2012.6459320
Jun H. Choi, Yuandan Dong, T. Itoh
Frequency scanning antenna array based on composite right/left handed (CRLH) phased-array feed network is presented. The proposed array design method enables continuous beam scanning obtained through the feeding network design, which is different from the widely researched CRLH based leaky-wave antennas. It allows an added degree of freedom in designing frequency scanning antennas by taking the advantages of controlling the aperture field distribution and decoupling the element patterns from the array factor (AF) patters.
{"title":"Composite right/left-handed (CRLH) phased-array feed network for frequency scanning antenna","authors":"Jun H. Choi, Yuandan Dong, T. Itoh","doi":"10.23919/EUMC.2012.6459320","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459320","url":null,"abstract":"Frequency scanning antenna array based on composite right/left handed (CRLH) phased-array feed network is presented. The proposed array design method enables continuous beam scanning obtained through the feeding network design, which is different from the widely researched CRLH based leaky-wave antennas. It allows an added degree of freedom in designing frequency scanning antennas by taking the advantages of controlling the aperture field distribution and decoupling the element patterns from the array factor (AF) patters.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115095567","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 : 2012-12-01DOI: 10.23919/EUMC.2012.6459101
R. Wessalowski, R. Canters, G. V. van Rhoon
Combination of multimodality therapy with regional hyperthermia is a rewarding method to improve local tumor control rate and long term survival in children with high-risk tumors with dismal prognosis. Hyperthermia helps chemo refractory tumors to overcome their resistance to earlier applied chemotherapy. High quality hyperthermia is associated with treatment outcome and hence technological innovation will contribute to further enhance treatment outcome. Multiple channel heat applicators and non-invasive MR temperature monitoring for childhood cancer can produce precise target volumes with substantial sparing of normal tissue.
{"title":"EMF hyperthermia in children","authors":"R. Wessalowski, R. Canters, G. V. van Rhoon","doi":"10.23919/EUMC.2012.6459101","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459101","url":null,"abstract":"Combination of multimodality therapy with regional hyperthermia is a rewarding method to improve local tumor control rate and long term survival in children with high-risk tumors with dismal prognosis. Hyperthermia helps chemo refractory tumors to overcome their resistance to earlier applied chemotherapy. High quality hyperthermia is associated with treatment outcome and hence technological innovation will contribute to further enhance treatment outcome. Multiple channel heat applicators and non-invasive MR temperature monitoring for childhood cancer can produce precise target volumes with substantial sparing of normal tissue.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116628870","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 : 2012-12-01DOI: 10.23919/EUMC.2012.6459104
C. van den Berg, J. Bluemink, A. van Lier, M. Paulides, J. Bakker, R. Verhaart, J. Lagendijk, F. Simonis, E. Petersen, A. Raaijmakers
Monitoring of RF hyperthermia treatment by means of Magnetic Resonance Imaging is the logical thing to do. MRI is a versatile imaging modality capable of imaging anatomy, physiology and moreover, temperature. Thus, detailed treatment monitoring of hyperthermia becomes possible. In the last 10 to 15 years various successful MRI/hyperthermia systems have been built. In this same period, RF technology in MRI has undergone a tremendous expansion. This growth originates mainly from the RF challenges of going towards higher magnetic field strengths. Some of these developments offer very new exciting opportunities for hyperthermia and especially for hybrid MRI/hyperthermia systems. In this paper we discuss some of these prospects paving the way to next generation hybrid hyperthermia/MRI systems.
{"title":"MR and hyperthermia: Exploiting similarities for mutual benefit","authors":"C. van den Berg, J. Bluemink, A. van Lier, M. Paulides, J. Bakker, R. Verhaart, J. Lagendijk, F. Simonis, E. Petersen, A. Raaijmakers","doi":"10.23919/EUMC.2012.6459104","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459104","url":null,"abstract":"Monitoring of RF hyperthermia treatment by means of Magnetic Resonance Imaging is the logical thing to do. MRI is a versatile imaging modality capable of imaging anatomy, physiology and moreover, temperature. Thus, detailed treatment monitoring of hyperthermia becomes possible. In the last 10 to 15 years various successful MRI/hyperthermia systems have been built. In this same period, RF technology in MRI has undergone a tremendous expansion. This growth originates mainly from the RF challenges of going towards higher magnetic field strengths. Some of these developments offer very new exciting opportunities for hyperthermia and especially for hybrid MRI/hyperthermia systems. In this paper we discuss some of these prospects paving the way to next generation hybrid hyperthermia/MRI systems.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125968891","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 : 2012-12-01DOI: 10.23919/EUMC.2012.6459105
M. Paulides, Z. Rijnen, J. Bakker, P. Togni, P. Levendag, G. V. van Rhoon
Recent developments in simulation technology have expanded clinical use of hyperthermia treatment planning (HTP). HTP involves simulation of 1) the induced power absorption and 2) the induced temperature elevation distribution. Specifically the electromagnetic (EM) simulators have evolved into reliable tools providing accurate predictions of the absorbed power distributions applied during radiofrequency (RF) hyperthermia (HT). Such simulation tools are imperative for optimizing the energy delivery by phased array applicators with over four independent antennas. Consequently, HTP is currently being utilized in the clinic before, and during, deep-regional HT. For deep-local HT this strategy has even stronger potential but, due to steep thermal gradients, also more stringent quality requirements. In this paper, we exemplify the clinical implementation process for planning guided HT using phased-array HT applicators by reporting the steps taken for the HYPERcollar, a head and neck HT applicator. Besides treatment guidance, HTP allows applicator development, investigations into improved heating strategies and detailed assessment of confounding influences. In this way, treatment quality can been assessed and improved offline making HTP an inevitible tool in the improvement of deep-local HT when aiming at target conformal heat delivery.
{"title":"Treatment planning guided RF hyperthermia","authors":"M. Paulides, Z. Rijnen, J. Bakker, P. Togni, P. Levendag, G. V. van Rhoon","doi":"10.23919/EUMC.2012.6459105","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459105","url":null,"abstract":"Recent developments in simulation technology have expanded clinical use of hyperthermia treatment planning (HTP). HTP involves simulation of 1) the induced power absorption and 2) the induced temperature elevation distribution. Specifically the electromagnetic (EM) simulators have evolved into reliable tools providing accurate predictions of the absorbed power distributions applied during radiofrequency (RF) hyperthermia (HT). Such simulation tools are imperative for optimizing the energy delivery by phased array applicators with over four independent antennas. Consequently, HTP is currently being utilized in the clinic before, and during, deep-regional HT. For deep-local HT this strategy has even stronger potential but, due to steep thermal gradients, also more stringent quality requirements. In this paper, we exemplify the clinical implementation process for planning guided HT using phased-array HT applicators by reporting the steps taken for the HYPERcollar, a head and neck HT applicator. Besides treatment guidance, HTP allows applicator development, investigations into improved heating strategies and detailed assessment of confounding influences. In this way, treatment quality can been assessed and improved offline making HTP an inevitible tool in the improvement of deep-local HT when aiming at target conformal heat delivery.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115144852","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}
The vital sign, including respiration and heartbeat signal, can be detected through a non-contact Doppler radar. Since the harmonics and intermodulation products of the respiration are major interferences according to the previous researches, the heartbeat signal cannot be clearly identified without holding the breath, detected from back of the subject or just filtered to remove respiration signal. A synchronized motion technique (SMT) based on Doppler concept is proposed to suppress the interference from the respiration in non-contact heartbeat detection. The experiment results show that the SMT effectively improve the heartbeat-to-respiration ratio (HRR) up to 76 % while subject kept normal breathing. The SMT mechanism is also analyzed through non-linear simulation which agrees well with the measurement data.
{"title":"40-GHz vital sign detection of heartbeat using synchronized motion technique for respiration signal suppression","authors":"J. Cheng, Jin-Fu Yeh, Hong-Yuan Yang, Jeng‐Han Tsai, Jenshan Lin, Tian-Wei Huang","doi":"10.23919/EUMC.2012.6459289","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459289","url":null,"abstract":"The vital sign, including respiration and heartbeat signal, can be detected through a non-contact Doppler radar. Since the harmonics and intermodulation products of the respiration are major interferences according to the previous researches, the heartbeat signal cannot be clearly identified without holding the breath, detected from back of the subject or just filtered to remove respiration signal. A synchronized motion technique (SMT) based on Doppler concept is proposed to suppress the interference from the respiration in non-contact heartbeat detection. The experiment results show that the SMT effectively improve the heartbeat-to-respiration ratio (HRR) up to 76 % while subject kept normal breathing. The SMT mechanism is also analyzed through non-linear simulation which agrees well with the measurement data.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128155854","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 : 2012-12-01DOI: 10.23919/EUMC.2012.6459181
Pei-Hua Lo, Chien-Chih Lin, Hsin-Chih Kuo, H. Chuang
This paper presents a Ka-band variable gain amplifier (VGA) fabricated in a standard 0.18-μm CMOS process using the proposed cascade amplifier method to achieve both low phase variation and good output matching capacity in a variable gain mode. The proposed VGA achieves 14.2 dB gain control range with a phase variation of 8.9°. The input and output reflection coefficients versus the gain control bias at 26.6 GHz are below -19 dB and -10 dB, respectively. A 14.2 dB gain control range with low phase variation and good input and output matching is achieved. The chip size is 0.65 mm2 with pads.
{"title":"A Ka-band CMOS low-phase-variation variable gain amplifier with good matching capacity","authors":"Pei-Hua Lo, Chien-Chih Lin, Hsin-Chih Kuo, H. Chuang","doi":"10.23919/EUMC.2012.6459181","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459181","url":null,"abstract":"This paper presents a Ka-band variable gain amplifier (VGA) fabricated in a standard 0.18-μm CMOS process using the proposed cascade amplifier method to achieve both low phase variation and good output matching capacity in a variable gain mode. The proposed VGA achieves 14.2 dB gain control range with a phase variation of 8.9°. The input and output reflection coefficients versus the gain control bias at 26.6 GHz are below -19 dB and -10 dB, respectively. A 14.2 dB gain control range with low phase variation and good input and output matching is achieved. The chip size is 0.65 mm2 with pads.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130871896","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 : 2012-10-30DOI: 10.23919/EUMC.2012.6459109
F. Leferink, R. Serra, H. Schipper
Reverberation chambers create a statistical uniformly distributed field which is very useful for reliable electromagnetic interference measurements. Another advantage of these chambers is the high field strength which can be generated compared to conventional test setups. A reverberation chamber made of flexible cloth is called a vibrating intrinsic reverberation chamber (VIRC) and the field stirring is achieved by moving the (angle of) the walls. A new technique for shielding effectiveness measurements is the dual-VIRC method. In this method two VIRCs are combined together via a common wall with an aperture that forms the interface between them. This set-up makes it possible to achieve a very high dynamic range. A main advantage of this technique compared to the nested reverberation set-up is that measurements can be conducted much faster and at much lower frequency.
{"title":"Microwave-range shielding effectiveness measurements using a dual vibrating intrinsic reverberation chamber","authors":"F. Leferink, R. Serra, H. Schipper","doi":"10.23919/EUMC.2012.6459109","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459109","url":null,"abstract":"Reverberation chambers create a statistical uniformly distributed field which is very useful for reliable electromagnetic interference measurements. Another advantage of these chambers is the high field strength which can be generated compared to conventional test setups. A reverberation chamber made of flexible cloth is called a vibrating intrinsic reverberation chamber (VIRC) and the field stirring is achieved by moving the (angle of) the walls. A new technique for shielding effectiveness measurements is the dual-VIRC method. In this method two VIRCs are combined together via a common wall with an aperture that forms the interface between them. This set-up makes it possible to achieve a very high dynamic range. A main advantage of this technique compared to the nested reverberation set-up is that measurements can be conducted much faster and at much lower frequency.","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127809846","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 : 2012-10-29DOI: 10.23919/EUMC.2012.6459186
F. Ouasli, J. Coupez, P. Pajusco, C. Person
This paper describes a new broadband microstrip to coplanar strip (CPS) line transition, where supporting substrates are joined perpendicularly, one containing the CPS line and the other one the microstrip line. The CPS line is coupled to the microstrip line through a symmetric slot radial stub placed in the ground plane of the microstrip line substrate. A measured return loss greater than 10dB is obtained, with a corresponding -3dB back-to-back insertion loss bandwidth from 1.5 to 3.3 GHz. The proposed transition has several advantages compared to other configurations, especially in the context of phased antenna arrays, which require co-integration of planar radiating elements with differential access ports active circuitry. By changing the CPS by a slot line, a wideband microstrip-to-slot line transition has been also obtained, with a [1.5 - 3.7 GHz] bandwidth (@VSWR=2).
{"title":"Broadband microstrip to coplanar strip line/slot line transitions on perpendicular substrates","authors":"F. Ouasli, J. Coupez, P. Pajusco, C. Person","doi":"10.23919/EUMC.2012.6459186","DOIUrl":"https://doi.org/10.23919/EUMC.2012.6459186","url":null,"abstract":"This paper describes a new broadband microstrip to coplanar strip (CPS) line transition, where supporting substrates are joined perpendicularly, one containing the CPS line and the other one the microstrip line. The CPS line is coupled to the microstrip line through a symmetric slot radial stub placed in the ground plane of the microstrip line substrate. A measured return loss greater than 10dB is obtained, with a corresponding -3dB back-to-back insertion loss bandwidth from 1.5 to 3.3 GHz. The proposed transition has several advantages compared to other configurations, especially in the context of phased antenna arrays, which require co-integration of planar radiating elements with differential access ports active circuitry. By changing the CPS by a slot line, a wideband microstrip-to-slot line transition has been also obtained, with a [1.5 - 3.7 GHz] bandwidth (@VSWR=2).","PeriodicalId":266910,"journal":{"name":"2012 42nd European Microwave Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124334358","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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