Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645929
A. P. Shrestha, Jai-Jin Jung, K. Kwak
Physical layer security schemes for wireless communication can prevent eavesdropping even without use of upper layer cryptographic algorithms. As such, physical layer security based on information theoretic constraint is gaining both theoretical and practical importance in research community. In this paper, we investigate the physical layer security for wireless multicasting scheme consisting of a single antenna transmitter with multiple receivers and eavesdroppers both equipped with multiple antennas under quasi-static Rayleigh fading channel. We develop new closed-form expressions for the analysis of probability of positive secrecy as well as outage probability. We show that the physical layer security can be maintained even in presence of multiple eavesdroppers consisting multiple antennas. Furthermore, we also analyze the effect of number of antennas, users and eavesdroppers in the numerical results.
{"title":"Secure wireless multicasting in presence of multiple eavesdroppers","authors":"A. P. Shrestha, Jai-Jin Jung, K. Kwak","doi":"10.1109/ISCIT.2013.6645929","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645929","url":null,"abstract":"Physical layer security schemes for wireless communication can prevent eavesdropping even without use of upper layer cryptographic algorithms. As such, physical layer security based on information theoretic constraint is gaining both theoretical and practical importance in research community. In this paper, we investigate the physical layer security for wireless multicasting scheme consisting of a single antenna transmitter with multiple receivers and eavesdroppers both equipped with multiple antennas under quasi-static Rayleigh fading channel. We develop new closed-form expressions for the analysis of probability of positive secrecy as well as outage probability. We show that the physical layer security can be maintained even in presence of multiple eavesdroppers consisting multiple antennas. Furthermore, we also analyze the effect of number of antennas, users and eavesdroppers in the numerical results.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124418818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645931
Ratchanok Chaipraserth, A. Leelasantitham, S. Kiattisin
Nowadays, the growth of IT business are highly competitive both of development process and functionality of software to meet mostly customer requirements. Normally, software performance should develop to increase the high quality whilst it should reduce both of the cost and the time. The IT business is to start the attention with satisfaction of the customer for expanding opportunities of grown business. The problem of former software development is an operation under the pressure conditions affecting to see more bugs of the software in a period of testing system and delivering the program to the required customer. This paper presents an implementation of approach which is an agile development (If what we do that able to modify the code to meet the requirement in the future, that's call agile.) using Test Driven Development (TDD) in automation testing framework for software development process. It helps optimization of software testing as it can found early bug, flexible for requirement changes in the future, either to increase or change requirement without any effect on coding behavior. It also helps to reduce cost of software development as a human resource, time and rapid feedback of test result. We apply this approach with prototype in software development processes using the Point of care testing (POCT) system which is as an example to create test case with black-box and white-box testing techniques based on the requirements specification to improve more product quality.
{"title":"A test automation framework in POCT system using TDD techniques","authors":"Ratchanok Chaipraserth, A. Leelasantitham, S. Kiattisin","doi":"10.1109/ISCIT.2013.6645931","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645931","url":null,"abstract":"Nowadays, the growth of IT business are highly competitive both of development process and functionality of software to meet mostly customer requirements. Normally, software performance should develop to increase the high quality whilst it should reduce both of the cost and the time. The IT business is to start the attention with satisfaction of the customer for expanding opportunities of grown business. The problem of former software development is an operation under the pressure conditions affecting to see more bugs of the software in a period of testing system and delivering the program to the required customer. This paper presents an implementation of approach which is an agile development (If what we do that able to modify the code to meet the requirement in the future, that's call agile.) using Test Driven Development (TDD) in automation testing framework for software development process. It helps optimization of software testing as it can found early bug, flexible for requirement changes in the future, either to increase or change requirement without any effect on coding behavior. It also helps to reduce cost of software development as a human resource, time and rapid feedback of test result. We apply this approach with prototype in software development processes using the Point of care testing (POCT) system which is as an example to create test case with black-box and white-box testing techniques based on the requirements specification to improve more product quality.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132314237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645938
M. Phothisonothai, Yasunori Arita, Katsumi Watanabe
Measures of irregularity and complexity in time-series data can be quantified by using fractal dimension (FD) which may convey useful information and showing a strong correlation with the physiological data, e.g., speech. The time-dependent FD (TDFD) has been proven to be effective method in various physiological studies. However, the TDFD result depends on the time windowing, i.e., length and type which could provide different features. Therefore, in this paper, the effects of time windowing of TDFD by spanning 28 to 212-point length and four window functions were investigated. The FD was computed by using Higuchi's method. In experiment, speech data recorded from 15 Japanese utterances, 4 different ways of expression (accosting, wholehearted, normal, and uninterested). The obtained results were useful in selecting time windowing based on TDFD method in which could extract different intonations effectively.
{"title":"Effects of time windowing for extraction of expression from Japanese speech: Higuchi's fractal dimension","authors":"M. Phothisonothai, Yasunori Arita, Katsumi Watanabe","doi":"10.1109/ISCIT.2013.6645938","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645938","url":null,"abstract":"Measures of irregularity and complexity in time-series data can be quantified by using fractal dimension (FD) which may convey useful information and showing a strong correlation with the physiological data, e.g., speech. The time-dependent FD (TDFD) has been proven to be effective method in various physiological studies. However, the TDFD result depends on the time windowing, i.e., length and type which could provide different features. Therefore, in this paper, the effects of time windowing of TDFD by spanning 28 to 212-point length and four window functions were investigated. The FD was computed by using Higuchi's method. In experiment, speech data recorded from 15 Japanese utterances, 4 different ways of expression (accosting, wholehearted, normal, and uninterested). The obtained results were useful in selecting time windowing based on TDFD method in which could extract different intonations effectively.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133745149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645934
Y. H. Chye, E. Dutkiewicz, R. Vesilo, R. Liu
The emerging technology of cognitive radio (CR) allows secondary users (SUs) to gain access to radio spectrum which is licensed to but temporarily unoccupied by primary users (PUs). Apart from spectrum sensing, dynamic spectrum access (DSA) is an important processing task for CR networks (CRNs). Its aim is to allocate spectrum for SUs dynamically without causing any harm to PUs. CRNs may support different traffic types that may have different quality of service (QoS) requirements. In order to meet these QoS requirements, channel states, queue states and traffic types should be taken into account in designing DSA schemes. However, traffic types handled by SUs are treated equally in most existing DSA schemes. We propose a cross-layer scheduling scheme by incorporating DSA, packet scheduling and a channel sharing policy to achieve efficient QoS support for SUs with different traffic types. QoS performance of the proposed scheduling scheme is evaluated in terms of average throughput, average packet delay and packet dropping probability for SUs with different traffic types. Simulation results show that the proposed scheduling scheme outperforms the conventional scheduling scheme by providing more efficient QoS support for SUs and higher throughput fairness among SUs as the PU's activity factor increases.
{"title":"A QoS-aware cross-layer scheduling scheme for multiuser mixed-traffic cognitive radio networks","authors":"Y. H. Chye, E. Dutkiewicz, R. Vesilo, R. Liu","doi":"10.1109/ISCIT.2013.6645934","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645934","url":null,"abstract":"The emerging technology of cognitive radio (CR) allows secondary users (SUs) to gain access to radio spectrum which is licensed to but temporarily unoccupied by primary users (PUs). Apart from spectrum sensing, dynamic spectrum access (DSA) is an important processing task for CR networks (CRNs). Its aim is to allocate spectrum for SUs dynamically without causing any harm to PUs. CRNs may support different traffic types that may have different quality of service (QoS) requirements. In order to meet these QoS requirements, channel states, queue states and traffic types should be taken into account in designing DSA schemes. However, traffic types handled by SUs are treated equally in most existing DSA schemes. We propose a cross-layer scheduling scheme by incorporating DSA, packet scheduling and a channel sharing policy to achieve efficient QoS support for SUs with different traffic types. QoS performance of the proposed scheduling scheme is evaluated in terms of average throughput, average packet delay and packet dropping probability for SUs with different traffic types. Simulation results show that the proposed scheduling scheme outperforms the conventional scheduling scheme by providing more efficient QoS support for SUs and higher throughput fairness among SUs as the PU's activity factor increases.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115614943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645878
A. López-Martín, R. Carvajal, J. Ramírez-Angulo
The optimal choice of output stages in CMOS transconductors in the presence of nonideal effects is analyzed. It is shown that current folding employing source-coupled differential pairs is advantageous versus the conventional approach based on current mirrors. Two versions of a CMOS transconductor, each one using one of the mentioned approaches, have been fabricated in a 0.5μm CMOS technology and tested. Measurement results confirm the linearity improvements of current folding at the output stage.
{"title":"On the optimal choice of the output stage in CMOS transconductors","authors":"A. López-Martín, R. Carvajal, J. Ramírez-Angulo","doi":"10.1109/ISCIT.2013.6645878","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645878","url":null,"abstract":"The optimal choice of output stages in CMOS transconductors in the presence of nonideal effects is analyzed. It is shown that current folding employing source-coupled differential pairs is advantageous versus the conventional approach based on current mirrors. Two versions of a CMOS transconductor, each one using one of the mentioned approaches, have been fabricated in a 0.5μm CMOS technology and tested. Measurement results confirm the linearity improvements of current folding at the output stage.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123705431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645910
S. Thainimit, Luís A. Alexandre, Vasco M N de Almeida
Human iris recognition systems are an attractive form of non-intrusive bio-identification with many potential applications. However, the accuracy of these systems is still limited due to challenges presented by iris surface deformation. This paper provides an introduction to the physiology of the iris, describes the problem of iris deformation, and presents a review of past and current software approaches to iris recognition. The focus is on methods related to the physiology of the iris.
{"title":"Iris surface deformation and normalization","authors":"S. Thainimit, Luís A. Alexandre, Vasco M N de Almeida","doi":"10.1109/ISCIT.2013.6645910","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645910","url":null,"abstract":"Human iris recognition systems are an attractive form of non-intrusive bio-identification with many potential applications. However, the accuracy of these systems is still limited due to challenges presented by iris surface deformation. This paper provides an introduction to the physiology of the iris, describes the problem of iris deformation, and presents a review of past and current software approaches to iris recognition. The focus is on methods related to the physiology of the iris.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125252206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645909
Chen Meng, Mohammed Raad, R. Raad
This paper describes an extension to Vector Base Amplitude Panning (VBAP) [7]. An audience targeting vector is introduced to the VBAP model to adjust the audio playback system according to the position of the audience. With this modification, it is possible to create virtual sound sources at positions that are better suited for the location of the target audience. Mobile applications such as mobile teleconferencing can take advantage of the surround sound technology to enhance the audio quality for users. In mobile surround, surround sound is produced by mobile telephone handsets, the locations of both the handsets and the audiences may vary during the play back. Therefore, we developed this vector based approach to allow us to move the loudspeakers and the audience independently from each other.
{"title":"Modified Vector Base Amplitude Panning implementation on smart devices","authors":"Chen Meng, Mohammed Raad, R. Raad","doi":"10.1109/ISCIT.2013.6645909","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645909","url":null,"abstract":"This paper describes an extension to Vector Base Amplitude Panning (VBAP) [7]. An audience targeting vector is introduced to the VBAP model to adjust the audio playback system according to the position of the audience. With this modification, it is possible to create virtual sound sources at positions that are better suited for the location of the target audience. Mobile applications such as mobile teleconferencing can take advantage of the surround sound technology to enhance the audio quality for users. In mobile surround, surround sound is produced by mobile telephone handsets, the locations of both the handsets and the audiences may vary during the play back. Therefore, we developed this vector based approach to allow us to move the loudspeakers and the audience independently from each other.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"158 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122503815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645812
Yang Zhang, Zheng Zhou, Yuhang Jia, Bin Li, Zhichao Qin
We present an efficient codeword search algorithm for limited feedback MIMO beamforming systems. Given a predefined codebook, identifying the best beamforming codeword may easily become inefficient in terms of computational complexity. To reduce the computational complexity during the codeword searching process, we propose a novel (off-line) preprocessing scheme, which specifies the feasible condition for efficient searching. By exploiting the triangle inequality principle for distance, we develop a promising kick-out condition to avoid computing the chordal distance in the presence of non-optimal codewords of the input vector. Numerical experimental results have shown that the computational burden of our proposed algorithm has been significantly reduced compared with the traditional exhaustive search.
{"title":"Efficient codeword search algorithm for limited feedback MIMO beamforming systems","authors":"Yang Zhang, Zheng Zhou, Yuhang Jia, Bin Li, Zhichao Qin","doi":"10.1109/ISCIT.2013.6645812","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645812","url":null,"abstract":"We present an efficient codeword search algorithm for limited feedback MIMO beamforming systems. Given a predefined codebook, identifying the best beamforming codeword may easily become inefficient in terms of computational complexity. To reduce the computational complexity during the codeword searching process, we propose a novel (off-line) preprocessing scheme, which specifies the feasible condition for efficient searching. By exploiting the triangle inequality principle for distance, we develop a promising kick-out condition to avoid computing the chordal distance in the presence of non-optimal codewords of the input vector. Numerical experimental results have shown that the computational burden of our proposed algorithm has been significantly reduced compared with the traditional exhaustive search.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129825768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645828
Y. Marye, Rong Sun, Hua-An Zhao
Cooperative communications is a very important mechanism to provide diversity for devices that are incapable of harboring multiple antennae by emulating MIMO system. Different strategies of cooperation exist such as amplify-and-forward (AF) and decode-and-forward (DF). Although cooperation is a viable means of fighting multi path fading, it inherently induces a reduction in spectral efficiency which is against the need for increased data rate of wireless networks. In this paper, adaptive modulation is applied on existing cooperative protocols (AF and DF) as an approach to compensate for spectral efficiency loss while cooperating. In addition, an approach based on the previously existing ones called CSI directed estimate and forward (CDEF) strategy that utilizes CSI better and results in better BER performance with improved spectral efficiency is proposed. Simulation results also confirm the improvements, highlighting a promising approach to satisfy high data rate demands by current and future wireless networks.
{"title":"CSI assisted and modulation adaptive wireless cooperation for increased spectral efficiency","authors":"Y. Marye, Rong Sun, Hua-An Zhao","doi":"10.1109/ISCIT.2013.6645828","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645828","url":null,"abstract":"Cooperative communications is a very important mechanism to provide diversity for devices that are incapable of harboring multiple antennae by emulating MIMO system. Different strategies of cooperation exist such as amplify-and-forward (AF) and decode-and-forward (DF). Although cooperation is a viable means of fighting multi path fading, it inherently induces a reduction in spectral efficiency which is against the need for increased data rate of wireless networks. In this paper, adaptive modulation is applied on existing cooperative protocols (AF and DF) as an approach to compensate for spectral efficiency loss while cooperating. In addition, an approach based on the previously existing ones called CSI directed estimate and forward (CDEF) strategy that utilizes CSI better and results in better BER performance with improved spectral efficiency is proposed. Simulation results also confirm the improvements, highlighting a promising approach to satisfy high data rate demands by current and future wireless networks.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129261225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/ISCIT.2013.6645843
Soumaya Dahi, S. Tabbane
This paper investigates the issue of determining an appropriate utility function to model the Secondary User (SU) preference toward spectrum holes on the basis of their duration. A Sigmoid shaped utility function is proposed and a proper tuning is discussed to improve the representation of SU preference and to involve the radio quality on the access decision process. The performance and the suitability of the proposed utility function is investigated within an access model whose purpose is to reduce handoff process related to PU activity.
{"title":"Sigmoid utility function formulation for handoff reducing Access model in cognitive radio","authors":"Soumaya Dahi, S. Tabbane","doi":"10.1109/ISCIT.2013.6645843","DOIUrl":"https://doi.org/10.1109/ISCIT.2013.6645843","url":null,"abstract":"This paper investigates the issue of determining an appropriate utility function to model the Secondary User (SU) preference toward spectrum holes on the basis of their duration. A Sigmoid shaped utility function is proposed and a proper tuning is discussed to improve the representation of SU preference and to involve the radio quality on the access decision process. The performance and the suitability of the proposed utility function is investigated within an access model whose purpose is to reduce handoff process related to PU activity.","PeriodicalId":356009,"journal":{"name":"2013 13th International Symposium on Communications and Information Technologies (ISCIT)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129776991","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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