Pub Date : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8003985
Durga Kumari, K. K. Sharma
This paper describes the isolation between two radiating I shaped patch antennas operating at Millimeter wave frequency 60 GHz for future 5G wireless communication applications. To reduce mutual coupling between antennas Slotted meander line structure is used. Antenna return loss is − 26dB and isolation between antennas obtained is −29dB. Gain of the desired radiating antenna is 12.7dB and it covers the bandwidth 5.77 GHz. The antenna is simulated by the software Computer Simulated technology (CST).
{"title":"Improved isolation between antennas using slotted meander line structure for 5G wireless applications","authors":"Durga Kumari, K. K. Sharma","doi":"10.1109/COMPTELIX.2017.8003985","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8003985","url":null,"abstract":"This paper describes the isolation between two radiating I shaped patch antennas operating at Millimeter wave frequency 60 GHz for future 5G wireless communication applications. To reduce mutual coupling between antennas Slotted meander line structure is used. Antenna return loss is − 26dB and isolation between antennas obtained is −29dB. Gain of the desired radiating antenna is 12.7dB and it covers the bandwidth 5.77 GHz. The antenna is simulated by the software Computer Simulated technology (CST).","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"30 1","pages":"312-314"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85302684","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8003931
Kamayani Shrivastav, R. P. Yadav
This paper addresses the statistical analysis of Transceiver Phase Noise (PHN) effect on Orthogonal Frequency Division Multiple Access (OFDMA) Uplink system performance for arbitrary subcarrier mapping. In most of the previous publications Complex Gaussian distribution of Inter Carrier Interference (ICI) was assumed, however in this paper we derive a closed form expression for the signal-to-interference+ noise ratio (SINR) without such restriction and then analyse it as a function of critical system parameters. This improved evaluation stringently specifies the plausible acceptable PHN characteristics for a certain OFDMA Uplink system and explains the serious under specification of Local Oscillator (LO) with Gaussian approximation.
{"title":"Analytical study of SINR for OFDMA Uplink in presence of Transceiver Phase Noise","authors":"Kamayani Shrivastav, R. P. Yadav","doi":"10.1109/COMPTELIX.2017.8003931","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8003931","url":null,"abstract":"This paper addresses the statistical analysis of Transceiver Phase Noise (PHN) effect on Orthogonal Frequency Division Multiple Access (OFDMA) Uplink system performance for arbitrary subcarrier mapping. In most of the previous publications Complex Gaussian distribution of Inter Carrier Interference (ICI) was assumed, however in this paper we derive a closed form expression for the signal-to-interference+ noise ratio (SINR) without such restriction and then analyse it as a function of critical system parameters. This improved evaluation stringently specifies the plausible acceptable PHN characteristics for a certain OFDMA Uplink system and explains the serious under specification of Local Oscillator (LO) with Gaussian approximation.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"13 1","pages":"21-26"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72981823","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8004019
Pradeep Yadav, Rishi Gupta, Sandeep Kumar
The main aim of this paper is to reduce the computational time, to increase the complexity ratio and to improve the image quality by applying dither Dither Block Truncation coding algorithm with different similarity comparison algorithm, as different approaches are followed to improve the quality of an image, ODBTC is one of the approach, but to improve the quality we will also include some of the best similarity measurement algorithm like normalized and mini-max ratio, on the other hand feature selection is also one of the important factor to improve the performance measurement, previously we were using color(CF) and bit pattern(BF) separately but here we will combine both color with bit pattern(CBF)feature so more improved result will occur.
{"title":"Content based image retrieval using Dither Block Truncation coding with similarity comparison algorithm","authors":"Pradeep Yadav, Rishi Gupta, Sandeep Kumar","doi":"10.1109/COMPTELIX.2017.8004019","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8004019","url":null,"abstract":"The main aim of this paper is to reduce the computational time, to increase the complexity ratio and to improve the image quality by applying dither Dither Block Truncation coding algorithm with different similarity comparison algorithm, as different approaches are followed to improve the quality of an image, ODBTC is one of the approach, but to improve the quality we will also include some of the best similarity measurement algorithm like normalized and mini-max ratio, on the other hand feature selection is also one of the important factor to improve the performance measurement, previously we were using color(CF) and bit pattern(BF) separately but here we will combine both color with bit pattern(CBF)feature so more improved result will occur.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"1 1","pages":"489-493"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74868937","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8004023
A. Deo, Anuradha Sonker, R. Kumar
In this paper, reconfigurable slot antenna for LTE (2.6GHz), AMT-fixed service (4.5GHz), and WLAN (5.4GHz) applications is presented. There are two L-shaped slots and a U-shaped slot inserted in the ground plane. The size of the antenna is reduced as a result of these slots. There are three varactor diodes inserted in these slots. This is done for the purpose of frequency, directivity, and polarization reconfiguration. The directivities and polarization states of the antenna are changed at different frequencies i.e. at 2.6GHz, 5.4GHz, and at 4.5 GHz. These three different frequencies correspond to different states of the antenna. The states of the antenna are changed by switching the varactor diodes on and off. The varactor diodes are used in this paper as they have the property of fast frequency tuning.
{"title":"Design of reconfigurable slot antenna using varactor diode","authors":"A. Deo, Anuradha Sonker, R. Kumar","doi":"10.1109/COMPTELIX.2017.8004023","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8004023","url":null,"abstract":"In this paper, reconfigurable slot antenna for LTE (2.6GHz), AMT-fixed service (4.5GHz), and WLAN (5.4GHz) applications is presented. There are two L-shaped slots and a U-shaped slot inserted in the ground plane. The size of the antenna is reduced as a result of these slots. There are three varactor diodes inserted in these slots. This is done for the purpose of frequency, directivity, and polarization reconfiguration. The directivities and polarization states of the antenna are changed at different frequencies i.e. at 2.6GHz, 5.4GHz, and at 4.5 GHz. These three different frequencies correspond to different states of the antenna. The states of the antenna are changed by switching the varactor diodes on and off. The varactor diodes are used in this paper as they have the property of fast frequency tuning.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"34 1","pages":"511-515"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73381102","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8003946
S. V. Naghavi, A. Safavi
Most processes in modern industries are physically distributed and generally composed of different subsystems, which characterized by significant interactions. In this paper, we investigate a decentralized Model Predictive Control (DMPC) approach for these systems over finite moving horizon at the presence of multiple faults occurring at unknown time-instants. Besides, the implementation of a control strategy can be achieved via a packet-based communication networks. The decentralized control strategy is combined with an online approximation method to deal with the unknown interconnection effects and multiple faults. This structure is implemented for each subsystem via the DMPC algorithm subject to some constraints. Meanwhile, the proposed structure is studied in the networked control system framework. It is proved that the proposed method guarantees input-to-state stability characterization for both local subsystems and the global system under some predetermined assumptions. The illustrative example is presented to explain the proposed strategy.
{"title":"Decentralized Model Predictive Control of interconnected nonlinear systems at the presence of faults over communication network","authors":"S. V. Naghavi, A. Safavi","doi":"10.1109/COMPTELIX.2017.8003946","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8003946","url":null,"abstract":"Most processes in modern industries are physically distributed and generally composed of different subsystems, which characterized by significant interactions. In this paper, we investigate a decentralized Model Predictive Control (DMPC) approach for these systems over finite moving horizon at the presence of multiple faults occurring at unknown time-instants. Besides, the implementation of a control strategy can be achieved via a packet-based communication networks. The decentralized control strategy is combined with an online approximation method to deal with the unknown interconnection effects and multiple faults. This structure is implemented for each subsystem via the DMPC algorithm subject to some constraints. Meanwhile, the proposed structure is studied in the networked control system framework. It is proved that the proposed method guarantees input-to-state stability characterization for both local subsystems and the global system under some predetermined assumptions. The illustrative example is presented to explain the proposed strategy.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"31 1","pages":"101-106"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82114554","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8003970
Y. Yadav, Gaurav Jajoo, S. K. Yadav
Modulation scheme detection of blind signal is vital area of research now a days because of the requirement in security and communication applications. In this paper, modulation class is identified based on the constellation graphical representation. Carrier frequency, symbol rate and phase offset are the essential parameters required for the extraction of constellation diagram, which are calculated efficiently. Efficient way of Classification between ASK, PSK and QAM is proposed in this paper. ASK and pool of PSK and QAM is separated using linear regression, and further classification between PSK and QAM has done using circle fitting.
{"title":"Modulation scheme detection of blind signal using constellation graphical representation","authors":"Y. Yadav, Gaurav Jajoo, S. K. Yadav","doi":"10.1109/COMPTELIX.2017.8003970","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8003970","url":null,"abstract":"Modulation scheme detection of blind signal is vital area of research now a days because of the requirement in security and communication applications. In this paper, modulation class is identified based on the constellation graphical representation. Carrier frequency, symbol rate and phase offset are the essential parameters required for the extraction of constellation diagram, which are calculated efficiently. Efficient way of Classification between ASK, PSK and QAM is proposed in this paper. ASK and pool of PSK and QAM is separated using linear regression, and further classification between PSK and QAM has done using circle fitting.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"36 1","pages":"231-235"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79800295","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8003989
Vaishali Kansal, M. Dave
The increased number of cyber attacks makes the availability of services a major security concern. One common type of cyber threat is distributed denial of service (DDoS). A DDoS attack is aimed at disrupting the legitimate users from accessing the services. It is easier for an insider having legitimate access to the system to deceive any security controls resulting in insider attack. This paper proposes an Early Detection and Isolation Policy (EDIP)to mitigate insider-assisted DDoS attacks. EDIP detects insider among all legitimate clients present in the system at proxy level and isolate it from innocent clients by migrating it to attack proxy. Further an effective algorithm for detection and isolation of insider is developed with the aim of maximizing attack isolation while minimizing disruption to benign clients. In addition, concept of load balancing is used to prevent proxies from getting overloaded.
{"title":"Proactive DDoS attack detection and isolation","authors":"Vaishali Kansal, M. Dave","doi":"10.1109/COMPTELIX.2017.8003989","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8003989","url":null,"abstract":"The increased number of cyber attacks makes the availability of services a major security concern. One common type of cyber threat is distributed denial of service (DDoS). A DDoS attack is aimed at disrupting the legitimate users from accessing the services. It is easier for an insider having legitimate access to the system to deceive any security controls resulting in insider attack. This paper proposes an Early Detection and Isolation Policy (EDIP)to mitigate insider-assisted DDoS attacks. EDIP detects insider among all legitimate clients present in the system at proxy level and isolate it from innocent clients by migrating it to attack proxy. Further an effective algorithm for detection and isolation of insider is developed with the aim of maximizing attack isolation while minimizing disruption to benign clients. In addition, concept of load balancing is used to prevent proxies from getting overloaded.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"135 1","pages":"334-338"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80302445","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8003950
Varshali Sharma, S. K. Saini, Ritu Sharma
In this paper various design of channel ADD Drop filter using photonic crystal ring resonator is investigated. In design I, ADF based on quasi-square PCRR with circular scatters is proposed and analysed for optimized performance. This device consists of rectangular waveguides and a quasi-square PCRR. A good wavelength selective filter with bandwidth about 10.20nm and centre wavelength of pass band 1.4201um is achieved. In the next design, photonic crystal quasi-square cavity based ADF is realised with elliptical scatters for different major and minor axis configurations thus having different ellipticity. It is observed that the output response of the filter is very sensitive to the dimensions of coupling rods and scatter rods. It is observed that when the radius of the scatter rods is increased, then the centre wavelength of the bands get shifted towards higher wavelength range.
{"title":"Design of channel ADD Drop filter using photonic crystal ring resonator","authors":"Varshali Sharma, S. K. Saini, Ritu Sharma","doi":"10.1109/COMPTELIX.2017.8003950","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8003950","url":null,"abstract":"In this paper various design of channel ADD Drop filter using photonic crystal ring resonator is investigated. In design I, ADF based on quasi-square PCRR with circular scatters is proposed and analysed for optimized performance. This device consists of rectangular waveguides and a quasi-square PCRR. A good wavelength selective filter with bandwidth about 10.20nm and centre wavelength of pass band 1.4201um is achieved. In the next design, photonic crystal quasi-square cavity based ADF is realised with elliptical scatters for different major and minor axis configurations thus having different ellipticity. It is observed that the output response of the filter is very sensitive to the dimensions of coupling rods and scatter rods. It is observed that when the radius of the scatter rods is increased, then the centre wavelength of the bands get shifted towards higher wavelength range.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"25 1","pages":"124-129"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80409717","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8003951
N. Singh, N. Choudhary
Automatic segmentation of tumor abnormality is a very difficult task for the radiologist. In this research, we proposed a located brain tumor with automatic seed point localization and no need to initially select the location of the region which is to be infected. Estimation of the abnormalities for initial bounding box after this, we proposed the segmentation of tumor called automatic level set minimization function with a new technique that is localization based energy minimization of MRI brain tumor. The performance of localization is evaluated using based on the level of detection and radiologist analytical results. Total 100 FLAIR, T1, and T2-weighted MRI brain tumor images (Astrocytoma (22), Ganglioglioma (6), Glioblastoma (23), Epidermoide (3), Mixed Glioma (5) and Meningnet (41)) (5type of tumors) were used for the experiment. Experimental results show that the method has successfully localized the brain tumors with 97% accuracy.
{"title":"Automatic localization and level set based energy minimization for MRI brain tumor","authors":"N. Singh, N. Choudhary","doi":"10.1109/COMPTELIX.2017.8003951","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8003951","url":null,"abstract":"Automatic segmentation of tumor abnormality is a very difficult task for the radiologist. In this research, we proposed a located brain tumor with automatic seed point localization and no need to initially select the location of the region which is to be infected. Estimation of the abnormalities for initial bounding box after this, we proposed the segmentation of tumor called automatic level set minimization function with a new technique that is localization based energy minimization of MRI brain tumor. The performance of localization is evaluated using based on the level of detection and radiologist analytical results. Total 100 FLAIR, T1, and T2-weighted MRI brain tumor images (Astrocytoma (22), Ganglioglioma (6), Glioblastoma (23), Epidermoide (3), Mixed Glioma (5) and Meningnet (41)) (5type of tumors) were used for the experiment. Experimental results show that the method has successfully localized the brain tumors with 97% accuracy.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"55 1","pages":"130-134"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89480811","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 : 2017-07-01DOI: 10.1109/COMPTELIX.2017.8004033
Sunakshi Jaitly, H. Malhotra, B. Bhushan
Wireless sensor network is a collection of several nodes in a network capable of sharing information in wireless medium. Due to the presence of wireless medium it is highly vulnerable to network attacks. WSN has many applications ranging from monitoring of environment to highly restricted military and surveillance where security is a major requirement. The most common and dangerous attack which can be proved harmful for WSN is jamming attack. In jamming an adversary can limit the capabilities of WSN communication by interfering with RF signals using certain jamming devices. Securing a WSN is one of the major concerns of network safety. In this paper, we have discussed various jamming techniques and types of jammers. We have also listed some countermeasures of jamming which, if used, depending on the application can significantly reduce the chances and effects of jamming. Some limitations and challenges of WSN are also explained. Starting from the introduction about the WSN, our work will cover all the pros and cons of the jammers and countermeasures which can help an interested researcher to gain some knowledge about the topic.
{"title":"Security vulnerabilities and countermeasures against jamming attacks in Wireless Sensor Networks: A survey","authors":"Sunakshi Jaitly, H. Malhotra, B. Bhushan","doi":"10.1109/COMPTELIX.2017.8004033","DOIUrl":"https://doi.org/10.1109/COMPTELIX.2017.8004033","url":null,"abstract":"Wireless sensor network is a collection of several nodes in a network capable of sharing information in wireless medium. Due to the presence of wireless medium it is highly vulnerable to network attacks. WSN has many applications ranging from monitoring of environment to highly restricted military and surveillance where security is a major requirement. The most common and dangerous attack which can be proved harmful for WSN is jamming attack. In jamming an adversary can limit the capabilities of WSN communication by interfering with RF signals using certain jamming devices. Securing a WSN is one of the major concerns of network safety. In this paper, we have discussed various jamming techniques and types of jammers. We have also listed some countermeasures of jamming which, if used, depending on the application can significantly reduce the chances and effects of jamming. Some limitations and challenges of WSN are also explained. Starting from the introduction about the WSN, our work will cover all the pros and cons of the jammers and countermeasures which can help an interested researcher to gain some knowledge about the topic.","PeriodicalId":6917,"journal":{"name":"2017 International Conference on Computer, Communications and Electronics (Comptelix)","volume":"13 1","pages":"559-564"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87865340","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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