Pub Date : 2014-07-24DOI: 10.1109/TENCONSPRING.2014.6863082
Mehdi Jahanirad, A. W. A. Abdul Wahab, N. B. Anuar, Mohd Yamani Idna Idris, M. N. Ayub
Sources such as speakers and environments from different communication devices produce signal variations that result in interference generated by different communication devices. Despite these convolutions, signal variations produced by different mobile devices leave intrinsic fingerprints on recorded calls, thus allowing the tracking of the models and brands of engaged mobile devices. This study aims to investigate the use of recorded Voice over Internet Protocol calls in the blind identification of source mobile devices. The proposed scheme employs a combination of entropy and mel-frequency cepstrum coefficients to extract the intrinsic features of mobile devices and analyzes these features with a multi-class support vector machine classifier. The experimental results lead to an accurate identification of 10 source mobile devices with an average accuracy of 99.72%.
{"title":"Blind identification of source mobile devices using VoIP calls","authors":"Mehdi Jahanirad, A. W. A. Abdul Wahab, N. B. Anuar, Mohd Yamani Idna Idris, M. N. Ayub","doi":"10.1109/TENCONSPRING.2014.6863082","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863082","url":null,"abstract":"Sources such as speakers and environments from different communication devices produce signal variations that result in interference generated by different communication devices. Despite these convolutions, signal variations produced by different mobile devices leave intrinsic fingerprints on recorded calls, thus allowing the tracking of the models and brands of engaged mobile devices. This study aims to investigate the use of recorded Voice over Internet Protocol calls in the blind identification of source mobile devices. The proposed scheme employs a combination of entropy and mel-frequency cepstrum coefficients to extract the intrinsic features of mobile devices and analyzes these features with a multi-class support vector machine classifier. The experimental results lead to an accurate identification of 10 source mobile devices with an average accuracy of 99.72%.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132469804","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 : 2014-07-24DOI: 10.1109/TENCONSPRING.2014.6863010
Amina Ahmed Mohamed, T. Wan
Transmission of one data packet from one node to another without collision is considered as the main task in MAC protocols, although single node transmission is easy compared to many nodes (multi-hop). EML-MAC, is a new TDMA based Medium Access Control MAC protocol, which is designed for general WSN applications to improve the energy efficiency, the main objective of this study is to enhance the existing work of EML-MAC in terms of energy consumption within the multi-hop wireless sensor network. A clustering algorithm, GANG, is used to address this issue. The proposed MAC protocol is further divided into contention based intra-cluster communications, and EML-MAC slot-based inter-cluster communication phases. The trade-offs between energy consumption and time synchronization in a multi-hop environment is controlled and the network life time is increased in EML-MAC GANG protocol.
{"title":"Enhanced mobile lightweight medium access control protocol for multi-hop wireless sensor network","authors":"Amina Ahmed Mohamed, T. Wan","doi":"10.1109/TENCONSPRING.2014.6863010","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863010","url":null,"abstract":"Transmission of one data packet from one node to another without collision is considered as the main task in MAC protocols, although single node transmission is easy compared to many nodes (multi-hop). EML-MAC, is a new TDMA based Medium Access Control MAC protocol, which is designed for general WSN applications to improve the energy efficiency, the main objective of this study is to enhance the existing work of EML-MAC in terms of energy consumption within the multi-hop wireless sensor network. A clustering algorithm, GANG, is used to address this issue. The proposed MAC protocol is further divided into contention based intra-cluster communications, and EML-MAC slot-based inter-cluster communication phases. The trade-offs between energy consumption and time synchronization in a multi-hop environment is controlled and the network life time is increased in EML-MAC GANG protocol.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115538379","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 : 2014-07-24DOI: 10.1109/TENCONSPRING.2014.6863041
Raza Umar, Mohamed Deriche, A. Sheikh
Cognitive radio is an emerging technology which offers dynamic and opportunistic access to under utilized spectrum resources. Energy detection is the dominantly used spectrum sensing approach owing to its low computational complexity and ability to identify spectrum holes without requiring a priori knowledge of primary transmission characteristics. In this paper, we discuss the challenges in using the Gaussian approximation to the exact test statistics of energy detector. More importantly, we present an in depth analysis on the validity of the Gaussian approximation under practical sensing scenarios. Specifically, in addition to the number of observed samples, the roles of signal to noise ratio and performance constraints in terms of required probability of detection or allowed false-alarm rate are highlighted when the Gaussian approximation is used instead of the exact test statistics.
{"title":"On the validity of Gaussian approximations to exact test statistics of energy detector based spectrum sensing for cognitive radios","authors":"Raza Umar, Mohamed Deriche, A. Sheikh","doi":"10.1109/TENCONSPRING.2014.6863041","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863041","url":null,"abstract":"Cognitive radio is an emerging technology which offers dynamic and opportunistic access to under utilized spectrum resources. Energy detection is the dominantly used spectrum sensing approach owing to its low computational complexity and ability to identify spectrum holes without requiring a priori knowledge of primary transmission characteristics. In this paper, we discuss the challenges in using the Gaussian approximation to the exact test statistics of energy detector. More importantly, we present an in depth analysis on the validity of the Gaussian approximation under practical sensing scenarios. Specifically, in addition to the number of observed samples, the roles of signal to noise ratio and performance constraints in terms of required probability of detection or allowed false-alarm rate are highlighted when the Gaussian approximation is used instead of the exact test statistics.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127580857","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 : 2014-04-14DOI: 10.1109/TENCONSPRING.2014.6863032
I. Ibrahim, T. A. Rahman, M. Sabran, M. Jamlos
The Radial Line Slot Array (RLSA) Antenna is very pleasing due to low profile appearance and high gain characteristic. Recent research on RLSA is to produce a light weight, durable and easy fabrication process. Thus, FR4 is an alternative substrate to replace the polypropylene. This paper presents a comparison of polypropylene and FR4 dielectric substrate for linear polarized Radial Line Slot Array (RLSA) antenna at 5.8 GHz frequency. Both antennas implemented the same radiating slot design in an antenna with diameter of 200mm. The results show an improvement of radiation pattern using FR4 dielectric substrate as compare to polypropylene dielectric base. However, the reflection coefficient for polypropylene substrate show specific resonant at 5.8GHz frequency while FR4 substrate introduce multiple resonant. This paper also suggested FR4 board can be a potential substrate and major component for RLSA antenna development in future.
{"title":"Comparison of polypropylene and FR4 dielectric cavity for RLSA antenna design at 5.8GHz","authors":"I. Ibrahim, T. A. Rahman, M. Sabran, M. Jamlos","doi":"10.1109/TENCONSPRING.2014.6863032","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863032","url":null,"abstract":"The Radial Line Slot Array (RLSA) Antenna is very pleasing due to low profile appearance and high gain characteristic. Recent research on RLSA is to produce a light weight, durable and easy fabrication process. Thus, FR4 is an alternative substrate to replace the polypropylene. This paper presents a comparison of polypropylene and FR4 dielectric substrate for linear polarized Radial Line Slot Array (RLSA) antenna at 5.8 GHz frequency. Both antennas implemented the same radiating slot design in an antenna with diameter of 200mm. The results show an improvement of radiation pattern using FR4 dielectric substrate as compare to polypropylene dielectric base. However, the reflection coefficient for polypropylene substrate show specific resonant at 5.8GHz frequency while FR4 substrate introduce multiple resonant. This paper also suggested FR4 board can be a potential substrate and major component for RLSA antenna development in future.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115748411","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 : 2014-04-14DOI: 10.1109/TENCONSPRING.2014.6862999
J. Chahl
This paper introduces two unusual optical range finders and compares them to each other and to stereo and optical flow based range finding. The axially displaced sensor uses to optical flow sensitive cameras at different distances to the scene. The paraxial array sensor uses an array of light sensitive elements that can be optically or mechanically rotated to provide a range measurement. Both sensors are demonstrated in applications that are appropriate to their attributes. The displaced sensor is demonstrated as an altitude sensor for an aircraft, the paraxial sensor is demonstrated as a point range finder.
{"title":"Alternate optical range finder geometries","authors":"J. Chahl","doi":"10.1109/TENCONSPRING.2014.6862999","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6862999","url":null,"abstract":"This paper introduces two unusual optical range finders and compares them to each other and to stereo and optical flow based range finding. The axially displaced sensor uses to optical flow sensitive cameras at different distances to the scene. The paraxial array sensor uses an array of light sensitive elements that can be optically or mechanically rotated to provide a range measurement. Both sensors are demonstrated in applications that are appropriate to their attributes. The displaced sensor is demonstrated as an altitude sensor for an aircraft, the paraxial sensor is demonstrated as a point range finder.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116460801","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 : 2014-04-14DOI: 10.1109/TENCONSPRING.2014.6863043
Sherlyn C. dela Cruz, C. K. Roque, L. Alarcón
In this study, two parameter enhancement techniques, Transformer-based power combining and Diode linearization, which can improve the performance of a power amplifier, are implemented on a Class AB PA and then combined to determine their effectiveness. Using a 1.2-V 90nm CMOS process, a test chip containing the power combining network is fabricated and tested. The obtained results show that the power combining technique increases POUT by 13dB in exchange of 2X die area increase. The diode linearizer improves 1-dB input compression point by 1.3dB, IM3 up to 5dB and APC first offset frequency WiMAX specification by 10dB. These are all attained in exchange of a 1.1dB insertion loss.
在本研究中，基于变压器的功率组合和二极管线性化两种参数增强技术可以提高功率放大器的性能，并在AB类PA上实现，然后组合确定它们的有效性。采用1.2 v 90nm CMOS工艺，制作并测试了包含功率组合网络的测试芯片。结果表明，功率组合技术使POUT提高了13dB，而芯片面积增加了2倍。二极管线性化器将1db输入压缩点提高了1.3dB, IM3提高了5dB, APC第一偏移频率WiMAX规范提高了10dB。这些都是以1.1dB的插入损耗为代价获得的。
{"title":"1.2-V 5.8-GHz 90nm CMOS RF power amplifier parameter enhancement techniques","authors":"Sherlyn C. dela Cruz, C. K. Roque, L. Alarcón","doi":"10.1109/TENCONSPRING.2014.6863043","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863043","url":null,"abstract":"In this study, two parameter enhancement techniques, Transformer-based power combining and Diode linearization, which can improve the performance of a power amplifier, are implemented on a Class AB PA and then combined to determine their effectiveness. Using a 1.2-V 90nm CMOS process, a test chip containing the power combining network is fabricated and tested. The obtained results show that the power combining technique increases POUT by 13dB in exchange of 2X die area increase. The diode linearizer improves 1-dB input compression point by 1.3dB, IM3 up to 5dB and APC first offset frequency WiMAX specification by 10dB. These are all attained in exchange of a 1.1dB insertion loss.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122482688","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 : 2014-04-14DOI: 10.1109/TENCONSPRING.2014.6863027
Wan Azani B. Wan Mustafa, H. Yazid, Sazali bin Yaacob, Shafriza Nisha Bin Basah
Diabetic retinopathy is an eye problem that faced by the diabetic's patient. Diabetic Retinopathy (DR) is caused by the changes of the blood vessel in the retina. In first stage in DR, the blood vessels leak fluid and expandable. However, in the advance stage of DR a new blood vessel that fragile and abnormal may formed and leaks blood to the retina. This can caused vision loss or even blindness. Therefore, this paper proposes to extract the blood vessel based on peak and valley detection. The proposed methods utilized a green channel image and the inversion image. In this work, 20 images are utilized namely from Digital Retina Images for Vessel Extraction (DRIVE). The resulting images are compared with the benchmark images in term of sensitivity and specificity. The average sensitivity and specificity for the proposed method is 99.6% and 47.9% respectively.
{"title":"Blood vessel extraction using morphological operation for diabetic retinopathy","authors":"Wan Azani B. Wan Mustafa, H. Yazid, Sazali bin Yaacob, Shafriza Nisha Bin Basah","doi":"10.1109/TENCONSPRING.2014.6863027","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863027","url":null,"abstract":"Diabetic retinopathy is an eye problem that faced by the diabetic's patient. Diabetic Retinopathy (DR) is caused by the changes of the blood vessel in the retina. In first stage in DR, the blood vessels leak fluid and expandable. However, in the advance stage of DR a new blood vessel that fragile and abnormal may formed and leaks blood to the retina. This can caused vision loss or even blindness. Therefore, this paper proposes to extract the blood vessel based on peak and valley detection. The proposed methods utilized a green channel image and the inversion image. In this work, 20 images are utilized namely from Digital Retina Images for Vessel Extraction (DRIVE). The resulting images are compared with the benchmark images in term of sensitivity and specificity. The average sensitivity and specificity for the proposed method is 99.6% and 47.9% respectively.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130532847","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 : 2014-04-14DOI: 10.1109/TENCONSPRING.2014.6863068
Khoi-Nguyen Le-Huu, Diem N. Ho, Anh-Vu Dinh-Duc, T. Vu
Digital Signal Processors (DSPs), compared to general-purpose processors, have shown their great contribution to the implementation of digital signal processing algorithms such as digital filtering and Fourier analysis. This work deals with the RISC instruction set architecture (ISA) for the 32-bit VLIW Fixed-point DSP processor core proposed in our previous work. The designed DSP has been described in terms of groups of instructions, the opcode maps, and suggested design of the data path based on the proposed ISA. Moreover, advanced and enhanced instructions aimed at audio and image applications will also be presented in this work.
{"title":"Towards a RISC instruction set architecture for the 32-bit VLIW DSP processor core","authors":"Khoi-Nguyen Le-Huu, Diem N. Ho, Anh-Vu Dinh-Duc, T. Vu","doi":"10.1109/TENCONSPRING.2014.6863068","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863068","url":null,"abstract":"Digital Signal Processors (DSPs), compared to general-purpose processors, have shown their great contribution to the implementation of digital signal processing algorithms such as digital filtering and Fourier analysis. This work deals with the RISC instruction set architecture (ISA) for the 32-bit VLIW Fixed-point DSP processor core proposed in our previous work. The designed DSP has been described in terms of groups of instructions, the opcode maps, and suggested design of the data path based on the proposed ISA. Moreover, advanced and enhanced instructions aimed at audio and image applications will also be presented in this work.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114566239","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 : 2014-04-14DOI: 10.1109/TENCONSPRING.2014.6862986
Albin Sui Hian Kuek, H. T. Su, M. K. Haldar
A sextuple-mode ultra-wideband bandpass filter with wide upper stopband is presented in this paper. The wide upper stopband is achieved by attaching two open-circuited stubs 90° from the feed lines inside a ring resonator. These stubs introduce two transmission zeroes above the UWB passband to enhance the upper stopband. Analytical design of the six transmission poles and two transmission zeroes is described. The filter is then fabricated on RT/Duroid 6010.2LM substrate and measured. The simulated and measured responses are in good agreement showing upper stopband greater than 20dB up to 28GHz.
{"title":"Sextuple-mode ultra-wideband bandpass filter with wide upper stopband","authors":"Albin Sui Hian Kuek, H. T. Su, M. K. Haldar","doi":"10.1109/TENCONSPRING.2014.6862986","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6862986","url":null,"abstract":"A sextuple-mode ultra-wideband bandpass filter with wide upper stopband is presented in this paper. The wide upper stopband is achieved by attaching two open-circuited stubs 90° from the feed lines inside a ring resonator. These stubs introduce two transmission zeroes above the UWB passband to enhance the upper stopband. Analytical design of the six transmission poles and two transmission zeroes is described. The filter is then fabricated on RT/Duroid 6010.2LM substrate and measured. The simulated and measured responses are in good agreement showing upper stopband greater than 20dB up to 28GHz.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121706084","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 : 2014-04-14DOI: 10.1109/TENCONSPRING.2014.6863001
Baojie Chen, Edwin Yue Bun Pun
Ultra-broadband emission from 1300 to 1600 nm were obtained in Nd3+/Tm3+/Er3+ triply-doped germanate glasses, and single mode K+-Na+ion-exchanged channel waveguides at 1550 nm were obtained. The rare earth ions triply doped glasses are promising for the realization of ultra-broadband amplifiers, tunable lasers and broadband light sources.
{"title":"Triply-doped germanate glasses for ultra-broadband optical devices","authors":"Baojie Chen, Edwin Yue Bun Pun","doi":"10.1109/TENCONSPRING.2014.6863001","DOIUrl":"https://doi.org/10.1109/TENCONSPRING.2014.6863001","url":null,"abstract":"Ultra-broadband emission from 1300 to 1600 nm were obtained in Nd<sup>3+</sup>/Tm<sup>3+</sup>/Er<sup>3+</sup> triply-doped germanate glasses, and single mode K<sup>+</sup>-Na<sup>+</sup>ion-exchanged channel waveguides at 1550 nm were obtained. The rare earth ions triply doped glasses are promising for the realization of ultra-broadband amplifiers, tunable lasers and broadband light sources.","PeriodicalId":270495,"journal":{"name":"2014 IEEE REGION 10 SYMPOSIUM","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124377616","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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