Pub Date : 2020-05-01DOI: 10.1109/ICP46580.2020.9206422
T. Marzuki, A. Mansoor, H. Rashid, N. Omar, S. A. Ibrahim
This paper reports the optical signal amplifying performance of a Gallium co-doped Erbium (Er/Ga) fiber amplifier. The performance was analyzed for various input power and Er/Ga fiber length. The amplifier was constructed in a singlepass arrangement and operated with 980 nm pumping. At input signal power of −30 dBm, a maximum gain of 22.45 dB was obtained with noise figure of 5.71 dB at 1535 nm.
{"title":"Gallium-Erbium Fiber Amplifier","authors":"T. Marzuki, A. Mansoor, H. Rashid, N. Omar, S. A. Ibrahim","doi":"10.1109/ICP46580.2020.9206422","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206422","url":null,"abstract":"This paper reports the optical signal amplifying performance of a Gallium co-doped Erbium (Er/Ga) fiber amplifier. The performance was analyzed for various input power and Er/Ga fiber length. The amplifier was constructed in a singlepass arrangement and operated with 980 nm pumping. At input signal power of −30 dBm, a maximum gain of 22.45 dB was obtained with noise figure of 5.71 dB at 1535 nm.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"18 1","pages":"99-100"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81865514","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206452
M. Gamel, P. Ker, H. J. Lee, Wan Emilin Suliza wan Abd Rashid, M. Z. Jamaludin, A. I. Mohammed
Narrow bandgap (NB) materials provide better potential for infrared radiation conversion to electricity from solar or various thermophotovoltaic (TPV) spectrums. Different NB materials generate diverse output performance depending on the properties of materials crystal and cell configuration. Decreasing the bandgap of the materials will improve the collection of longer wavelength photons, but that tends to increase the recombination rate and reduce cell efficiency $(eta)$. This paper investigates the performance of NB cells. Silvaco TCAD software was used to simulate the output performance of germanium (Ge), indium arsenide (InAs), gallium antimonide (GaSb), and indium gallium arsenide (InGaAs) cells under solar spectrum AM1.5 and 1000 K illumination spectrums. It was found that InGaAs is the most outstanding material for photovoltaic (PV) application and TPV application at 1000 K radiation temperature. The comparative study and conclusion drawn in this work highlight several limitations in NB cells configuration, such as the high surface recombination rate in GaSb and InAs TPV cell, which reduces photocurrent collection.
{"title":"Performance Comparison of Narrow Bandgap Semiconductor Cells for Photovoltaic and Thermophotovoltaic Applications","authors":"M. Gamel, P. Ker, H. J. Lee, Wan Emilin Suliza wan Abd Rashid, M. Z. Jamaludin, A. I. Mohammed","doi":"10.1109/ICP46580.2020.9206452","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206452","url":null,"abstract":"Narrow bandgap (NB) materials provide better potential for infrared radiation conversion to electricity from solar or various thermophotovoltaic (TPV) spectrums. Different NB materials generate diverse output performance depending on the properties of materials crystal and cell configuration. Decreasing the bandgap of the materials will improve the collection of longer wavelength photons, but that tends to increase the recombination rate and reduce cell efficiency $(eta)$. This paper investigates the performance of NB cells. Silvaco TCAD software was used to simulate the output performance of germanium (Ge), indium arsenide (InAs), gallium antimonide (GaSb), and indium gallium arsenide (InGaAs) cells under solar spectrum AM1.5 and 1000 K illumination spectrums. It was found that InGaAs is the most outstanding material for photovoltaic (PV) application and TPV application at 1000 K radiation temperature. The comparative study and conclusion drawn in this work highlight several limitations in NB cells configuration, such as the high surface recombination rate in GaSb and InAs TPV cell, which reduces photocurrent collection.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"154 1","pages":"42-43"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79755727","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206485
Nurul Awadah Nadiah Binti Suhaimi, Izaddeen Kabir Yakasai, P. E. Abas, F. Begum
A novel photonic crystal fiber has been proposed for sensing liquid cocaine in terahertz frequencies. By varying the fiber's core ellipse height, simulation results have shown a high relative sensitivity above 85%, high birefringence of 0.018 and extremely low transmission effective material loss at 1 THz.
{"title":"Novel Terahertz Photonic Crystal Fiber for Liquid Cocaine Sensing","authors":"Nurul Awadah Nadiah Binti Suhaimi, Izaddeen Kabir Yakasai, P. E. Abas, F. Begum","doi":"10.1109/ICP46580.2020.9206485","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206485","url":null,"abstract":"A novel photonic crystal fiber has been proposed for sensing liquid cocaine in terahertz frequencies. By varying the fiber's core ellipse height, simulation results have shown a high relative sensitivity above 85%, high birefringence of 0.018 and extremely low transmission effective material loss at 1 THz.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"1 1","pages":"7-8"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83271072","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206469
Z. Hafizi, E. Vorathin
This paper presented an aluminium diaphragm-based FBG pressure sensor for pressure measurement of underwater pipeline. The proposed pressure sensor obtained a pressure sensitivity of 2.43 nm/MPa across the range of 0 MPa to 0.3 MPa with good linearity of 99.95 %. Furthermore, this pressure sensor has also equipped with temperature sensing FBG for temperature compensation.
{"title":"A Temperature-Compensated FBG Pressure Sensor for Underwater Pipeline Monitoring","authors":"Z. Hafizi, E. Vorathin","doi":"10.1109/ICP46580.2020.9206469","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206469","url":null,"abstract":"This paper presented an aluminium diaphragm-based FBG pressure sensor for pressure measurement of underwater pipeline. The proposed pressure sensor obtained a pressure sensitivity of 2.43 nm/MPa across the range of 0 MPa to 0.3 MPa with good linearity of 99.95 %. Furthermore, this pressure sensor has also equipped with temperature sensing FBG for temperature compensation.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"94 1","pages":"66-67"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88960276","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206423
G. Witjaksono, Z. Ullah, Illani Nawi, N. Tansu, Muhamad Irfan Khattak, M. Junaid
Gate tunable graphene-metal hybrid nanoantenna is proposed here with detailed numerical simulations carried out to evaluate the absorption of multi-layer graphene nanoantenna at terahertz frequencies, specifically at far-infrared. The investigated graphene nanoantenna composes of multi-layer graphene stack formation, which is placed above the gold hexagon radiator to efficiently couple activated graphene plasmons. The efficient coupled plasmons between graphene layers and gold hexagon increase the absorption of the antenna. Furthermore, the relationship between the absorption and multi-layer graphene is analysed by changing the Fermi energy of the graphene sheet, thus providing tunability of broadband absorption at a wide range of frequencies. The investigated nanoantenna has a resonant frequency at 30.5 THz with a bandwidth of 0.6 THz, while the trilayer graphene nanoantenna results in better absorption almost reaching 100% with a bandwidth of 2.5 THz. The simulation of the graphene-metal antenna is performed in CST studio by using an FDTD solver. The designed antenna has various utilizations in the field of photonics i.e. terahertz imaging, sensing, and spectroscopy applications.
{"title":"Absorption Enhancement of Tunable Terahertz Hybrid Graphene-Metal Antenna with Stacked Graphene configuration","authors":"G. Witjaksono, Z. Ullah, Illani Nawi, N. Tansu, Muhamad Irfan Khattak, M. Junaid","doi":"10.1109/ICP46580.2020.9206423","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206423","url":null,"abstract":"Gate tunable graphene-metal hybrid nanoantenna is proposed here with detailed numerical simulations carried out to evaluate the absorption of multi-layer graphene nanoantenna at terahertz frequencies, specifically at far-infrared. The investigated graphene nanoantenna composes of multi-layer graphene stack formation, which is placed above the gold hexagon radiator to efficiently couple activated graphene plasmons. The efficient coupled plasmons between graphene layers and gold hexagon increase the absorption of the antenna. Furthermore, the relationship between the absorption and multi-layer graphene is analysed by changing the Fermi energy of the graphene sheet, thus providing tunability of broadband absorption at a wide range of frequencies. The investigated nanoantenna has a resonant frequency at 30.5 THz with a bandwidth of 0.6 THz, while the trilayer graphene nanoantenna results in better absorption almost reaching 100% with a bandwidth of 2.5 THz. The simulation of the graphene-metal antenna is performed in CST studio by using an FDTD solver. The designed antenna has various utilizations in the field of photonics i.e. terahertz imaging, sensing, and spectroscopy applications.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"16 1","pages":"15-17"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77087479","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206426
Mohd Fahmi Azman, M. Mokhtar, Nawal Athirah Mustaffa, Zulkifli Mahmud, H. Abdul-Rashid
The strain magnification effect on the conventional single mode fiber (SMF) is investigated by using solid mechanics module in COMSOL Multiphysics. The strain effect is measured by applying the hydrostatic pressure on the SMF. In this paper, different coating materials and the position of the SMF in the coating are investigated. The investigation of the strain magnification effect on the SMF by COMSOL will help to produce the best coating's parameters of SMF which suits well in distributed pressure sensing application.
{"title":"Investigation of Strain Magnification Effect on Fiber Optic by Using COMSOL Multiphysics Software","authors":"Mohd Fahmi Azman, M. Mokhtar, Nawal Athirah Mustaffa, Zulkifli Mahmud, H. Abdul-Rashid","doi":"10.1109/ICP46580.2020.9206426","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206426","url":null,"abstract":"The strain magnification effect on the conventional single mode fiber (SMF) is investigated by using solid mechanics module in COMSOL Multiphysics. The strain effect is measured by applying the hydrostatic pressure on the SMF. In this paper, different coating materials and the position of the SMF in the coating are investigated. The investigation of the strain magnification effect on the SMF by COMSOL will help to produce the best coating's parameters of SMF which suits well in distributed pressure sensing application.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"47 1","pages":"72-73"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81356619","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206478
A. E. Hamzah, M. Zan, M. Elgaud, Mahmoud Muhanad Fadhel, S. A. Alwash, A. A. Abushagur, M. Mokhtar, Nur Hidayah Azeman, Sawal Hamid bin Mohd Ali, A. Bakar
This article describes the feasibility of signal generation by employing the System on Chip (SoC) ZedBoard™ platform to produce intensity modulation in Time Division Multiplexing-fiber Bragg grating sensor. SoC has the capability to reduce complexity and increase the flexibility in the design of digital instruments. Experimental results show that the system can regulate the period and Duty cycle for two output waveforms and frequency. The employment of SoC in the TDM-FBG sensor system provides overall performance enhancement over the conventional single pulse, since it shows a rapid response time of 3.4 ns compared to 8.2 ns when Arbitrary Waveform Generator is used. Further enhancement on accuracy can be done by using a high-speed digital-analog converter board with a higher sampling rate.
{"title":"Signal Generation using System on Chip for Coded Fiber Bragg Grating Sensor","authors":"A. E. Hamzah, M. Zan, M. Elgaud, Mahmoud Muhanad Fadhel, S. A. Alwash, A. A. Abushagur, M. Mokhtar, Nur Hidayah Azeman, Sawal Hamid bin Mohd Ali, A. Bakar","doi":"10.1109/ICP46580.2020.9206478","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206478","url":null,"abstract":"This article describes the feasibility of signal generation by employing the System on Chip (SoC) ZedBoard™ platform to produce intensity modulation in Time Division Multiplexing-fiber Bragg grating sensor. SoC has the capability to reduce complexity and increase the flexibility in the design of digital instruments. Experimental results show that the system can regulate the period and Duty cycle for two output waveforms and frequency. The employment of SoC in the TDM-FBG sensor system provides overall performance enhancement over the conventional single pulse, since it shows a rapid response time of 3.4 ns compared to 8.2 ns when Arbitrary Waveform Generator is used. Further enhancement on accuracy can be done by using a high-speed digital-analog converter board with a higher sampling rate.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"1 1","pages":"80-81"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88416761","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206421
Mansoor Khan, R. Sonkar
This paper presents the loss factor effect on the behaviour of Modulation Instability (MI) in Thulium Doped Fiber Amplifier (TDFA) operational in $mathbf{S}$ and near-C bands. Based on the derived analytical model, the relative change in maximum signal gain with respect to perturbation frequency was observed and compared to lossless TDFAs. At a smallsignal attenuation coefficient of 0.01 /m corresponding to smallsignal attenuation of 0.36 frequency shift of 1.44 THz was observed. Consequently, a reduction in signal gain of 45 dB was obtained for an input signal power of 250 mW. For the same set of parameters, the effect of non-linear and loss factor was studied and compared with present-day state-of-the-art Erbium Doped Fiber Amplifiers (EDFA). The results obtained can be used constructively in the selection of optimum perturbation frequency under MI phenomenon for the design of MI-based lasers employing TDFAs.
{"title":"Propagation Loss and Non-linear effects on Modulation Instability in Thulium Doped Fiber Amplifiers operating in S and near-C bands","authors":"Mansoor Khan, R. Sonkar","doi":"10.1109/ICP46580.2020.9206421","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206421","url":null,"abstract":"This paper presents the loss factor effect on the behaviour of Modulation Instability (MI) in Thulium Doped Fiber Amplifier (TDFA) operational in $mathbf{S}$ and near-C bands. Based on the derived analytical model, the relative change in maximum signal gain with respect to perturbation frequency was observed and compared to lossless TDFAs. At a smallsignal attenuation coefficient of 0.01 /m corresponding to smallsignal attenuation of 0.36 frequency shift of 1.44 THz was observed. Consequently, a reduction in signal gain of 45 dB was obtained for an input signal power of 250 mW. For the same set of parameters, the effect of non-linear and loss factor was studied and compared with present-day state-of-the-art Erbium Doped Fiber Amplifiers (EDFA). The results obtained can be used constructively in the selection of optimum perturbation frequency under MI phenomenon for the design of MI-based lasers employing TDFAs.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"40 1","pages":"1-2"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87328860","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206502
M. Zan, M. Elgaud, A. G. Abushagur, A. E. Hamzah, J. C. S. Teo, W. Y. Kiew, M. Mokhtar, N. Arsad, A. Bakar
The deployment of the differential form of Golay coding in TDM-FBG sensor is proposed and simulated. The spatial resolution associated to 20 cm was successfully achieved. Furthermore, the coding gain of 6 dB was achieved at Golay code length of 64 bits during 0 and 1500 μstrain applications.
{"title":"Spatial Resolution Enhancement of Time Domain Multiplexing Fiber Bragg Grating Sensor by Employing Differential Golay Codes","authors":"M. Zan, M. Elgaud, A. G. Abushagur, A. E. Hamzah, J. C. S. Teo, W. Y. Kiew, M. Mokhtar, N. Arsad, A. Bakar","doi":"10.1109/ICP46580.2020.9206502","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206502","url":null,"abstract":"The deployment of the differential form of Golay coding in TDM-FBG sensor is proposed and simulated. The spatial resolution associated to 20 cm was successfully achieved. Furthermore, the coding gain of 6 dB was achieved at Golay code length of 64 bits during 0 and 1500 μstrain applications.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"52 1","pages":"54-55"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81021745","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 : 2020-05-01DOI: 10.1109/ICP46580.2020.9206463
Junya Ishido, Minoru Watanabe
A wavelength-dependent optimization technique is proposed for two-dimensional (2D) holographic memories to improve the holographic memory recording density. When using holographic memory as electrical memory, a photodiode array is frequently used to convert diffracted light from the holographic memory to electrical signals. However, when using lasers of various wavelengths to read multiple contexts, although the light of each laser has different diffraction limitations, the photodiode array resolution must be designed based on the longest wavelength laser's light diffraction limitation. The proposed technique achieved the best recording density for a 2D holographic memory for lasers of every wavelength by adjusting the recording region size of the holographic memory for each context to satisfy the resolution of the photodiode array.
{"title":"Multi-context holographic memory exploiting a wavelength-dependent optimization technique","authors":"Junya Ishido, Minoru Watanabe","doi":"10.1109/ICP46580.2020.9206463","DOIUrl":"https://doi.org/10.1109/ICP46580.2020.9206463","url":null,"abstract":"A wavelength-dependent optimization technique is proposed for two-dimensional (2D) holographic memories to improve the holographic memory recording density. When using holographic memory as electrical memory, a photodiode array is frequently used to convert diffracted light from the holographic memory to electrical signals. However, when using lasers of various wavelengths to read multiple contexts, although the light of each laser has different diffraction limitations, the photodiode array resolution must be designed based on the longest wavelength laser's light diffraction limitation. The proposed technique achieved the best recording density for a 2D holographic memory for lasers of every wavelength by adjusting the recording region size of the holographic memory for each context to satisfy the resolution of the photodiode array.","PeriodicalId":6758,"journal":{"name":"2020 IEEE 8th International Conference on Photonics (ICP)","volume":"12 1","pages":"86-88"},"PeriodicalIF":0.0,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79136560","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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