We present an in-protocol Internet delay measurement technique for web browsing. By using the handshake and tear-down phases of a TCP protocol exchange as timers, we can make estimates of the round trip times without using an external tool, command or ICMP. During a web page request and retrieval, the latency encountered is typically caused by a combination of the end-terminal and network processing delays. One proportion of the delay, deterministic in nature, arises from the protocol processing or the speed of light propagation. Another proportion of the delay, more stochastic in nature, arises from interaction with cross traffic, queuing in buffers or web server response times. Our approach in this work is to clearly separate the sources into deterministic or stochastic types of delays. In order to evaluate our in-protocol measurement approach, we have identified two scenarios in two environments. The first scenario is the delays as seen by a client only on the public Internet, this is the most representative scenario from a user perspective. To quantify delays in more detail we have measured the delays at both a client and a server in our own research environment. We call this environment CheesePi, which is a Raspberry Pi measurement infrastructure. It currently runs over the SUNET Swedish academic network. It is important in this second scenario we can access both clients and servers in several locations.
{"title":"Delay characterization through in-protocol measurements","authors":"I. Marsh, L. McNamara, Rebecca Portelli","doi":"10.1145/3007120.3007166","DOIUrl":"https://doi.org/10.1145/3007120.3007166","url":null,"abstract":"We present an in-protocol Internet delay measurement technique for web browsing. By using the handshake and tear-down phases of a TCP protocol exchange as timers, we can make estimates of the round trip times without using an external tool, command or ICMP. During a web page request and retrieval, the latency encountered is typically caused by a combination of the end-terminal and network processing delays. One proportion of the delay, deterministic in nature, arises from the protocol processing or the speed of light propagation. Another proportion of the delay, more stochastic in nature, arises from interaction with cross traffic, queuing in buffers or web server response times. Our approach in this work is to clearly separate the sources into deterministic or stochastic types of delays. In order to evaluate our in-protocol measurement approach, we have identified two scenarios in two environments. The first scenario is the delays as seen by a client only on the public Internet, this is the most representative scenario from a user perspective. To quantify delays in more detail we have measured the delays at both a client and a server in our own research environment. We call this environment CheesePi, which is a Raspberry Pi measurement infrastructure. It currently runs over the SUNET Swedish academic network. It is important in this second scenario we can access both clients and servers in several locations.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125380243","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}
Shuhei Tsuchida, T. Takemori, T. Terada, M. Tsukamoto
When designing a performance involving people and mobile robots, we must consider the required functions and shape of the robot. However, it can be difficult to account for all of the requirements. In this paper, we discuss a mobile robot in the shape of a ball that is used in theatrical performances. Such a spherical robot should be agile and be able to roll like a ball. However, it is difficult to create a robot with all of these characteristics. Instead, we propose a mobile robot that can give the audience the optical illusion of the unique movements of a sphere by mounting a spherical LED display on a high-agility wheeled robot. The results of an experiment using a prototype indicate that this sort of robot can broaden the range of possible performances by giving the optical illusion of being a rolling sphere.
{"title":"Mimebot: Sphere-shaped Mobile Robot Imitating Rotational Movement","authors":"Shuhei Tsuchida, T. Takemori, T. Terada, M. Tsukamoto","doi":"10.1145/3007120.3007128","DOIUrl":"https://doi.org/10.1145/3007120.3007128","url":null,"abstract":"When designing a performance involving people and mobile robots, we must consider the required functions and shape of the robot. However, it can be difficult to account for all of the requirements. In this paper, we discuss a mobile robot in the shape of a ball that is used in theatrical performances. Such a spherical robot should be agile and be able to roll like a ball. However, it is difficult to create a robot with all of these characteristics. Instead, we propose a mobile robot that can give the audience the optical illusion of the unique movements of a sphere by mounting a spherical LED display on a high-agility wheeled robot. The results of an experiment using a prototype indicate that this sort of robot can broaden the range of possible performances by giving the optical illusion of being a rolling sphere.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"62 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123105567","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}
Smart device and body sensors have become innovative and converged with health informatics. To reduce the battery power consumption and bandwidth usage in wireless body area networks, it is proposed to infer sensed data in sensor nodes, which can raise an alarm when the user is in an urgent situation by analysing the sensed data against the user's activity status utilising accelerometer sensors. However when the activity changes frequently, there may be an increase in false alarms which increases sensing and transferring of data resulting in higher resource consumption. To reduce and mitigate the problem, we propose to verify the alarm using a smart device or smartwatch application so that a user can respond to whether the alarm is true or false, and thus provide feedback to the system to improve activity recognition. This paper presents a user-feedback system for use in activity recognition to mitigate and improve possible false alarm situations, which will consequently result in helping sensors to reduce the frequency of transactions and transmissions in wireless body area networks.
{"title":"Alarm Notification of Body Sensors Utilising Activity Recognition and Smart Device Application","authors":"James Jin Kang, T. Luan, Henry Larkin","doi":"10.1145/3007120.3007153","DOIUrl":"https://doi.org/10.1145/3007120.3007153","url":null,"abstract":"Smart device and body sensors have become innovative and converged with health informatics. To reduce the battery power consumption and bandwidth usage in wireless body area networks, it is proposed to infer sensed data in sensor nodes, which can raise an alarm when the user is in an urgent situation by analysing the sensed data against the user's activity status utilising accelerometer sensors. However when the activity changes frequently, there may be an increase in false alarms which increases sensing and transferring of data resulting in higher resource consumption. To reduce and mitigate the problem, we propose to verify the alarm using a smart device or smartwatch application so that a user can respond to whether the alarm is true or false, and thus provide feedback to the system to improve activity recognition. This paper presents a user-feedback system for use in activity recognition to mitigate and improve possible false alarm situations, which will consequently result in helping sensors to reduce the frequency of transactions and transmissions in wireless body area networks.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123116540","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}
GPS is the reference for outdoor positioning, implementing direct connection between satellite and receiver device. Indoor positioning raises challenges, locating target devices requiring wireless sensors networks and other technologies. Sensor networks deployed in buildings are commonly used for many applications based on location: surveillance, detection, navigation, etc. These indoor locating sensors generate data related to tracking information. Exploiting this information for investigation issues remains a relevant purpose. This paper context is related to indoor locations systems based on wireless cell, ICCARD sensors and video surveillance cameras. In this context, as no global reference system similar to GPS is available, the location information issued from various devices have neither standards nor common formats, and remain heterogeneous. This paper presents a contribution to extend our framework [24] to information generated by location sensor networks deployed in an indoor environment. The use case is illustrated in a forensic application [1].
{"title":"Mobile objects in indoor environment: Trajectories reconstruction","authors":"Franck Jeveme Panta, F. Sèdes","doi":"10.1145/3007120.3007154","DOIUrl":"https://doi.org/10.1145/3007120.3007154","url":null,"abstract":"GPS is the reference for outdoor positioning, implementing direct connection between satellite and receiver device. Indoor positioning raises challenges, locating target devices requiring wireless sensors networks and other technologies. Sensor networks deployed in buildings are commonly used for many applications based on location: surveillance, detection, navigation, etc. These indoor locating sensors generate data related to tracking information. Exploiting this information for investigation issues remains a relevant purpose. This paper context is related to indoor locations systems based on wireless cell, ICCARD sensors and video surveillance cameras. In this context, as no global reference system similar to GPS is available, the location information issued from various devices have neither standards nor common formats, and remain heterogeneous. This paper presents a contribution to extend our framework [24] to information generated by location sensor networks deployed in an indoor environment. The use case is illustrated in a forensic application [1].","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125211504","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}
J. Paay, D. Raptis, J. Kjeldskov, Bjarke M. Lauridsen, Ivan S. Penchev, Elias Ringhauge, Eric V. Ruder
In recent years there has been an increasing interest in cross-device interaction research involving mobile computing. We contribute to this research with a comparative study of four interaction techniques for moving information from a mobile device to a large display. The four techniques (Pinch, Swipe, Throw, and Tilt) were compared through a laboratory experiment with 53 participants, measuring their effectiveness, efficiency and error size. Findings from the experiment revealed that the Swipe technique performed best on all measures. In terms of effectiveness, the Tilt technique performed the worst, and especially so with small targets. In terms of efficiency and error size, the Pinch technique was the slowest and also the most imprecise. We also found that target size mattered considerably for all techniques, confirming previous research. Based on our findings we discuss why the individual techniques performed as observed, and discuss implications for using mobile devices in cross-device interaction design.
{"title":"A Comparison of Techniques for Cross-Device Interaction from Mobile Devices to Large Displays","authors":"J. Paay, D. Raptis, J. Kjeldskov, Bjarke M. Lauridsen, Ivan S. Penchev, Elias Ringhauge, Eric V. Ruder","doi":"10.1145/3007120.3007140","DOIUrl":"https://doi.org/10.1145/3007120.3007140","url":null,"abstract":"In recent years there has been an increasing interest in cross-device interaction research involving mobile computing. We contribute to this research with a comparative study of four interaction techniques for moving information from a mobile device to a large display. The four techniques (Pinch, Swipe, Throw, and Tilt) were compared through a laboratory experiment with 53 participants, measuring their effectiveness, efficiency and error size. Findings from the experiment revealed that the Swipe technique performed best on all measures. In terms of effectiveness, the Tilt technique performed the worst, and especially so with small targets. In terms of efficiency and error size, the Pinch technique was the slowest and also the most imprecise. We also found that target size mattered considerably for all techniques, confirming previous research. Based on our findings we discuss why the individual techniques performed as observed, and discuss implications for using mobile devices in cross-device interaction design.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132731561","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}
R. Bringula, Kharl John Rayala, Bernadette Anne Pascual, J. S. D. Leon, Kevin Sendino
This study determined the effects of four different forms of feedback (such as, complete solution, line-by-line correction, line-by-line hint, and correct-incorrect final answer) of a mobile-assisted learning application --- named LEA (linear equation aide) --- on linear equations on students' mathematics performance. Two hundred eighty five Grade 7 students (72 students each for the first-three feedback and 69 students for the last feedback) participated in a five-day experiment. It was revealed that students solved more problems and spent more time in the line-by-line hint type of feedback. The correct-incorrect final answer group had the most number of incorrect problems solved. It was disclosed that the scores of the students would be different from one another after they utilized the app. Nonetheless, all of them learned significantly from the app. Thus, the null hypothesis stating that there is no significant difference between the pretest and posttest scores of the students when categorized by different forms of feedback was rejected. Therefore, the use of the application is highly recommended for students beginning to learn linear equations. Recommendations and limitations were also presented.
{"title":"Effects of Different Types of Feedback of a Mobile Assisted Learning Application on Linear Equations on Students' Mathematics Performance","authors":"R. Bringula, Kharl John Rayala, Bernadette Anne Pascual, J. S. D. Leon, Kevin Sendino","doi":"10.1145/3007120.3007156","DOIUrl":"https://doi.org/10.1145/3007120.3007156","url":null,"abstract":"This study determined the effects of four different forms of feedback (such as, complete solution, line-by-line correction, line-by-line hint, and correct-incorrect final answer) of a mobile-assisted learning application --- named LEA (linear equation aide) --- on linear equations on students' mathematics performance. Two hundred eighty five Grade 7 students (72 students each for the first-three feedback and 69 students for the last feedback) participated in a five-day experiment. It was revealed that students solved more problems and spent more time in the line-by-line hint type of feedback. The correct-incorrect final answer group had the most number of incorrect problems solved. It was disclosed that the scores of the students would be different from one another after they utilized the app. Nonetheless, all of them learned significantly from the app. Thus, the null hypothesis stating that there is no significant difference between the pretest and posttest scores of the students when categorized by different forms of feedback was rejected. Therefore, the use of the application is highly recommended for students beginning to learn linear equations. Recommendations and limitations were also presented.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133275060","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}
Dong-Hoon Lee, Jung-hyun Kim, Ho-Youn Kim, Dong-Young Park
As Korea's standards organization, TTA published the common platform standard for smart TV based on HTML5 web runtime environments. Among the various technical features, this paper introduces a remote application control technology in which a companion device, such as smart phone or tablet, can control the smart TV's applications such as application query, launch, and terminate. It is based on multiscreen technology and the JSON-RPC profile. This paper explains the multiscreen core concept for device discovery and the session connection between the companion device and smart TV, and the definition of the request and response attributes of JSON-RPC to support remote application control. We also compare with the technology with the DIAL protocol developed by Netflix as a reference to emphasize the remote application control features. Additionally, this paper introduces a VOD service example utilizing the remote application control to evaluate the technology's feasibility with a smart TV emulator implementation.
{"title":"Remote Application Control Technology and Implementation of HTML5-based Smart TV Platform","authors":"Dong-Hoon Lee, Jung-hyun Kim, Ho-Youn Kim, Dong-Young Park","doi":"10.1145/3007120.3007159","DOIUrl":"https://doi.org/10.1145/3007120.3007159","url":null,"abstract":"As Korea's standards organization, TTA published the common platform standard for smart TV based on HTML5 web runtime environments. Among the various technical features, this paper introduces a remote application control technology in which a companion device, such as smart phone or tablet, can control the smart TV's applications such as application query, launch, and terminate. It is based on multiscreen technology and the JSON-RPC profile. This paper explains the multiscreen core concept for device discovery and the session connection between the companion device and smart TV, and the definition of the request and response attributes of JSON-RPC to support remote application control. We also compare with the technology with the DIAL protocol developed by Netflix as a reference to emphasize the remote application control features. Additionally, this paper introduces a VOD service example utilizing the remote application control to evaluate the technology's feasibility with a smart TV emulator implementation.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"185 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113982964","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}
Location tracking applications which receives frequent updates of a moving object's position, collect numerous moving objects' location data. Public transit agencies can make use of tracking data to optimize traffic control strategies. While improper use of trajectory data could cause individuals' privacy leakage. However, existing privacy-preserving techniques are unable to provide sufficient privacy protection. In this paper, we propose a data-dependent differentially private sanitization algorithm to publish moving object database. Moreover, we make use of a set of real-world constraints to conduct constraint inference, which can boost the utility of the published data. At last, we experimentally evaluate the utility of the sanitized data in terms of range-count queries, results show high utility and efficiency of our proposal.
{"title":"Differentially Private Moving Object Database Publication in Location Tracking Service","authors":"Zheng Huo, Teng Wang, Ping He","doi":"10.1145/3007120.3007149","DOIUrl":"https://doi.org/10.1145/3007120.3007149","url":null,"abstract":"Location tracking applications which receives frequent updates of a moving object's position, collect numerous moving objects' location data. Public transit agencies can make use of tracking data to optimize traffic control strategies. While improper use of trajectory data could cause individuals' privacy leakage. However, existing privacy-preserving techniques are unable to provide sufficient privacy protection. In this paper, we propose a data-dependent differentially private sanitization algorithm to publish moving object database. Moreover, we make use of a set of real-world constraints to conduct constraint inference, which can boost the utility of the published data. At last, we experimentally evaluate the utility of the sanitized data in terms of range-count queries, results show high utility and efficiency of our proposal.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114664308","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}
Gait authentication using a cell phone based accelerometer sensor offers an unobtrusive, user-friendly, and a periodic way of authenticating individuals to their smartphones. In this paper, we present a GMM-UBM based gait recognition approach for a realistic scenario (when the phone is placed inside the trouser pocket and the user is walking) by using the magnitude data of a smartphone-based tri-axes accelerometer sensor. To evaluate our approach we use a gait data set of 35 participants collected at their respective normal walking pace in two different sessions with an average gap of 25 days between the sessions. We obtained EERs of 3.031%, 11.531%, and 14.393% for the same-day, mix-days, and cross-days, respectively.
{"title":"Accelerometer based Gait Recognition using Adapted Gaussian Mixture Models","authors":"Muhammad Muaaz, R. Mayrhofer","doi":"10.1145/3007120.3007164","DOIUrl":"https://doi.org/10.1145/3007120.3007164","url":null,"abstract":"Gait authentication using a cell phone based accelerometer sensor offers an unobtrusive, user-friendly, and a periodic way of authenticating individuals to their smartphones. In this paper, we present a GMM-UBM based gait recognition approach for a realistic scenario (when the phone is placed inside the trouser pocket and the user is walking) by using the magnitude data of a smartphone-based tri-axes accelerometer sensor. To evaluate our approach we use a gait data set of 35 participants collected at their respective normal walking pace in two different sessions with an average gap of 25 days between the sessions. We obtained EERs of 3.031%, 11.531%, and 14.393% for the same-day, mix-days, and cross-days, respectively.","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124631210","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}
B. Abdulrazak, E. Pardede, M. Steinbauer, Ismail Khalil, Gabriele Anderst-Kotsis
Welcome to the 14th International Conference on Advances in Mobile Computing & Multimedia (MoMM), which is held in Singapore, on 28 - 30 November 2016, in conjunction with the 18th International Conference on Information Integration and Web-based Applications & Services (iiWAS).
{"title":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","authors":"B. Abdulrazak, E. Pardede, M. Steinbauer, Ismail Khalil, Gabriele Anderst-Kotsis","doi":"10.1145/3007120","DOIUrl":"https://doi.org/10.1145/3007120","url":null,"abstract":"Welcome to the 14th International Conference on Advances in Mobile Computing & Multimedia (MoMM), which is held in Singapore, on 28 - 30 November 2016, in conjunction with the 18th International Conference on Information Integration and Web-based Applications & Services (iiWAS).","PeriodicalId":394387,"journal":{"name":"Proceedings of the 14th International Conference on Advances in Mobile Computing and Multi Media","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116580468","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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