Pub Date : 2014-10-01DOI: 10.1109/ComComAp.2014.7017193
O. Diallo, J. Rodrigues, M. Sene, Guangjie Han, J. Niu
Wireless sensor networks (WSNs) have received a lot of attentions from both academic and industrial communities due to the wide range of applications they can provide. In this sort of network, maximizing the lifetime of sensor nodes as well as providing valid data in real-time are essential issues due to the real-time requirement of data and the resource limitation of sensor nodes. The distributed database approach has proven to be an effective approach to manage the large amount of sensed data in an energy-efficient manner and to reduce the response time of data processing. This work proposes a new query processing algorithm, which relies on a combination of a distributed database architecture with statistical techniques for improving the data processing in WSNs. The proposed query processing algorithm and the architecture were evaluated based on the temperature measures of an environment as a case study.
{"title":"Improving the data processing in WSNs through combination of a distributed approach and statistical techniques","authors":"O. Diallo, J. Rodrigues, M. Sene, Guangjie Han, J. Niu","doi":"10.1109/ComComAp.2014.7017193","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017193","url":null,"abstract":"Wireless sensor networks (WSNs) have received a lot of attentions from both academic and industrial communities due to the wide range of applications they can provide. In this sort of network, maximizing the lifetime of sensor nodes as well as providing valid data in real-time are essential issues due to the real-time requirement of data and the resource limitation of sensor nodes. The distributed database approach has proven to be an effective approach to manage the large amount of sensed data in an energy-efficient manner and to reduce the response time of data processing. This work proposes a new query processing algorithm, which relies on a combination of a distributed database architecture with statistical techniques for improving the data processing in WSNs. The proposed query processing algorithm and the architecture were evaluated based on the temperature measures of an environment as a case study.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121838944","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017187
Long Cao, Xin Chen, Yuqing Zhang, Donghui Li
Micro-blogging services are used by millions of people around the world to get information and express their opinions. Detecting hot topics from Chinese micro-bloggings has vast importance to discovering rumors and guiding public opinion. In order to solve the problem of massive pieces of information on micro-bloggings platform and the feature of micro-bloggins content such as short text, in this paper a model is put forward to detect hot topics from Chinese micro-bloggings based on word co-occurrence model. The experimental results show the model can efficiently detect hot topics from Chinese micro-bloggings.
{"title":"Hot topics detected from micro-bloggings based on word co-occurrence model","authors":"Long Cao, Xin Chen, Yuqing Zhang, Donghui Li","doi":"10.1109/ComComAp.2014.7017187","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017187","url":null,"abstract":"Micro-blogging services are used by millions of people around the world to get information and express their opinions. Detecting hot topics from Chinese micro-bloggings has vast importance to discovering rumors and guiding public opinion. In order to solve the problem of massive pieces of information on micro-bloggings platform and the feature of micro-bloggins content such as short text, in this paper a model is put forward to detect hot topics from Chinese micro-bloggings based on word co-occurrence model. The experimental results show the model can efficiently detect hot topics from Chinese micro-bloggings.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129759975","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017199
Xue Wu, Chao Liu, Qingxin Xia
Safety requirements have commanded increasing attention as software is playing a more and more important role in today's safety critical systems. As many experts, scholars have found that the main reason for safety critical systems' accident is bad requirements which means inaccurate, incomplete or inconsistent requirements may lead to misunderstanding of the system and may cause a fault in software design and realization, and brought disaster to people or environment. The main reason of bad requirements is poor communication between safety engineers and requirements analysis engineers. Safety requirements essentially are requirements to protect the software system go into a danger state which will cause lost of life or asset or environment damage. Safety requirements deal with errors, faults that the system may come across. So In this paper, we combine fault protection concepts with safety requirements, and propose a model-based safety requirements modeling approach named Safety RUCM to describe safety requirements in order to reduce inaccurate, incomplete or inconsistent safety requirements and at the same time to enhance mutual understanding on safety requirements between safety.
{"title":"Safety requirements modeling based on RUCM","authors":"Xue Wu, Chao Liu, Qingxin Xia","doi":"10.1109/ComComAp.2014.7017199","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017199","url":null,"abstract":"Safety requirements have commanded increasing attention as software is playing a more and more important role in today's safety critical systems. As many experts, scholars have found that the main reason for safety critical systems' accident is bad requirements which means inaccurate, incomplete or inconsistent requirements may lead to misunderstanding of the system and may cause a fault in software design and realization, and brought disaster to people or environment. The main reason of bad requirements is poor communication between safety engineers and requirements analysis engineers. Safety requirements essentially are requirements to protect the software system go into a danger state which will cause lost of life or asset or environment damage. Safety requirements deal with errors, faults that the system may come across. So In this paper, we combine fault protection concepts with safety requirements, and propose a model-based safety requirements modeling approach named Safety RUCM to describe safety requirements in order to reduce inaccurate, incomplete or inconsistent safety requirements and at the same time to enhance mutual understanding on safety requirements between safety.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121157529","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017179
Chen Xiao, Tiemeng Li, Nan Yang, Lifeng Wang, Shilong Ma
Video and audio streams in large-scale multimedia sensing system are high-volume, while computation and power resources are very scarce, which restricts the usage of complex data security process on multimedia data. Therefore, the confidentiality of video data under resources constraints is studied in this paper. Firstly, the trend of resources constraints is discussed, and an analysis model for multimedia data encryption optimization is proposed. Secondly, a general-purpose lightweight speed adjustable video encryption scheme is given. Thirdly, a series of selective encryption control models and their solution algorithms are proposed. Experimental analyses show the performances of the presented schemes are effective enough to support real-time multimedia sensing applications.
{"title":"A speed adjustable scheme based selective encryption control model for large-scale multimedia sensing system under resources constraints","authors":"Chen Xiao, Tiemeng Li, Nan Yang, Lifeng Wang, Shilong Ma","doi":"10.1109/ComComAp.2014.7017179","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017179","url":null,"abstract":"Video and audio streams in large-scale multimedia sensing system are high-volume, while computation and power resources are very scarce, which restricts the usage of complex data security process on multimedia data. Therefore, the confidentiality of video data under resources constraints is studied in this paper. Firstly, the trend of resources constraints is discussed, and an analysis model for multimedia data encryption optimization is proposed. Secondly, a general-purpose lightweight speed adjustable video encryption scheme is given. Thirdly, a series of selective encryption control models and their solution algorithms are proposed. Experimental analyses show the performances of the presented schemes are effective enough to support real-time multimedia sensing applications.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129164836","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017197
Yiding Wang, Qi Qi, Kefeng Li
A novel method for liveness detection of dorsal hand vein (DHV) based on AR model is proposed. Firstly, existing real DHV images are used to constitute a projection space based on modified principal component analysis (PCA). Unlike the previous works using the method of PCA, zero eigenvalues with their eigenvectors are used to constitute the projection space in this work. Secondly, test samples, including both real and fake DHV images, are projected to the projection space to produce one-dimensional vectors to extract their noise information. Then, autoregressive (AR) model is established for each test sample by estimating the power spectrum of the vector to detect the liveness of DHV. The proposed method is tested on a database of 510 real DHV images and 300 fake DHV images of 3 different types. The experimental results show that the proposed method performs well with an average recognition rate of 99%.
{"title":"Liveness detection of dorsal hand vein based on AutoRegressive model","authors":"Yiding Wang, Qi Qi, Kefeng Li","doi":"10.1109/ComComAp.2014.7017197","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017197","url":null,"abstract":"A novel method for liveness detection of dorsal hand vein (DHV) based on AR model is proposed. Firstly, existing real DHV images are used to constitute a projection space based on modified principal component analysis (PCA). Unlike the previous works using the method of PCA, zero eigenvalues with their eigenvectors are used to constitute the projection space in this work. Secondly, test samples, including both real and fake DHV images, are projected to the projection space to produce one-dimensional vectors to extract their noise information. Then, autoregressive (AR) model is established for each test sample by estimating the power spectrum of the vector to detect the liveness of DHV. The proposed method is tested on a database of 510 real DHV images and 300 fake DHV images of 3 different types. The experimental results show that the proposed method performs well with an average recognition rate of 99%.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131010746","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017217
Bassem Khalfi, Mahdi Ben Ghorbel, B. Hamdaoui, M. Guizani
This paper proposes an optimal power allocation analysis for a point-to-point wireless system when powered by a smart grid. We propose to minimize the total power consumption cost while ensuring individual and total throughput constraints. The power cost is computed based on different dynamic pricing models of the power consumption. Analytical solutions are derived for each pricing model. The derived solutions are shown to be modified versions of the water-filling solution. Water-filling based algorithms are proposed for the resource allocation with each pricing model. Performance comparison and pricing effect are shown through simulations.
{"title":"Optimal power allocation for smart-grid powered point-to-point cognitive radio system","authors":"Bassem Khalfi, Mahdi Ben Ghorbel, B. Hamdaoui, M. Guizani","doi":"10.1109/ComComAp.2014.7017217","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017217","url":null,"abstract":"This paper proposes an optimal power allocation analysis for a point-to-point wireless system when powered by a smart grid. We propose to minimize the total power consumption cost while ensuring individual and total throughput constraints. The power cost is computed based on different dynamic pricing models of the power consumption. Analytical solutions are derived for each pricing model. The derived solutions are shown to be modified versions of the water-filling solution. Water-filling based algorithms are proposed for the resource allocation with each pricing model. Performance comparison and pricing effect are shown through simulations.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134066519","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017160
Q. Cai, Yuqing Bai, Limin Sun, J. Niu
Conventional methods with measuring information propagation in static networks mainly rely on paths or the shortest path connecting nodes, whereas in opportunistic mobile social networks the existence of a path or the shortest path between nodes cannot be assumed due to the dynamic topological partition nature of the networks. This paper extends the concept of walk to dynamic settings and combines it with the Green's function that originates from statistical physics to quantify how much information flows through each node in the networks changing over time. By means of the time-evolving graph model and the calculation of weighted combinatorial dynamic walks on the graph, a concise theoretic result is derived to account for the relative information propagation capability of each mobile node based on the historical contacts. In addition, the iteration-form result can be conveniently computed at any time point and therefore can be used for predicting the future network behavior when the time interval is appropriately chosen in specific scenarios. Extensive experiments are conducted based on four real trace datasets and the results show that, the formula derived in this paper is very effective at quantifying the information that flows through each mobile node.
{"title":"Quantifying individual communication capability in opportunistic mobile social networks","authors":"Q. Cai, Yuqing Bai, Limin Sun, J. Niu","doi":"10.1109/ComComAp.2014.7017160","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017160","url":null,"abstract":"Conventional methods with measuring information propagation in static networks mainly rely on paths or the shortest path connecting nodes, whereas in opportunistic mobile social networks the existence of a path or the shortest path between nodes cannot be assumed due to the dynamic topological partition nature of the networks. This paper extends the concept of walk to dynamic settings and combines it with the Green's function that originates from statistical physics to quantify how much information flows through each node in the networks changing over time. By means of the time-evolving graph model and the calculation of weighted combinatorial dynamic walks on the graph, a concise theoretic result is derived to account for the relative information propagation capability of each mobile node based on the historical contacts. In addition, the iteration-form result can be conveniently computed at any time point and therefore can be used for predicting the future network behavior when the time interval is appropriately chosen in specific scenarios. Extensive experiments are conducted based on four real trace datasets and the results show that, the formula derived in this paper is very effective at quantifying the information that flows through each mobile node.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121259937","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017192
Yiding Wang, He Gong, Yun Fan, Haijun Cao
This paper introduces the design of a distributed wireless tree-like data acquisition system based on ZigBee, including its composition and the topological structure of ZigBee network. An industrial information transmission system based on ZigBee technology with CC2530 chip is designed. In this paper, every part of the hardware connections and software design will be introduced overall framework of the system. In consideration of the large data transmission and the security of wireless communication, a communication protocol of wireless transmission will be presented. The experimental tests, aiming at those following factors: distance, magnetic field, occlusion, temperature, short interval test and long-time test, have proved that the system has high speed of transmission and safety of information transmission.
{"title":"Design of a distributed wireless tree-like data acquisition system based on ZigBee","authors":"Yiding Wang, He Gong, Yun Fan, Haijun Cao","doi":"10.1109/ComComAp.2014.7017192","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017192","url":null,"abstract":"This paper introduces the design of a distributed wireless tree-like data acquisition system based on ZigBee, including its composition and the topological structure of ZigBee network. An industrial information transmission system based on ZigBee technology with CC2530 chip is designed. In this paper, every part of the hardware connections and software design will be introduced overall framework of the system. In consideration of the large data transmission and the security of wireless communication, a communication protocol of wireless transmission will be presented. The experimental tests, aiming at those following factors: distance, magnetic field, occlusion, temperature, short interval test and long-time test, have proved that the system has high speed of transmission and safety of information transmission.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116305036","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 : 2014-10-01DOI: 10.1109/COMCOMAP.2014.7017164
Zhao Kai, Cui Hui-juan, Tang Kun
This paper proposes a novel unequal error protection (UEP) resource allocation scheme for layered source transmission in coded OFDM systems. In the proposed scheme, firstly the resource allocation problem for two layered source is solved by UEP Fischer bit loading algorithm and golden search method. Secondly, according to the divide and conquer principle, the optimization of resource allocation for the multi-layered source can be decomposed hierarchically into sub-problems. And luckily, each sub-problem can be well solved by the above algorithm developed for the two layered source. Finally we design an efficient routine in which optimized resource allocation results for multi-layered source can be updated recursively through calculation and merging of solutions to the decomposed subproblems. Experimental results show that compared with traditional resource allocation schemes, the proposed scheme can effectively decrease the reconstructed distortion with moderate time complexity in a variety of channel conditions.
{"title":"A novel UEP resource allocation scheme for layered source transmission in COFDM systems","authors":"Zhao Kai, Cui Hui-juan, Tang Kun","doi":"10.1109/COMCOMAP.2014.7017164","DOIUrl":"https://doi.org/10.1109/COMCOMAP.2014.7017164","url":null,"abstract":"This paper proposes a novel unequal error protection (UEP) resource allocation scheme for layered source transmission in coded OFDM systems. In the proposed scheme, firstly the resource allocation problem for two layered source is solved by UEP Fischer bit loading algorithm and golden search method. Secondly, according to the divide and conquer principle, the optimization of resource allocation for the multi-layered source can be decomposed hierarchically into sub-problems. And luckily, each sub-problem can be well solved by the above algorithm developed for the two layered source. Finally we design an efficient routine in which optimized resource allocation results for multi-layered source can be updated recursively through calculation and merging of solutions to the decomposed subproblems. Experimental results show that compared with traditional resource allocation schemes, the proposed scheme can effectively decrease the reconstructed distortion with moderate time complexity in a variety of channel conditions.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114811008","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 : 2014-10-01DOI: 10.1109/ComComAp.2014.7017216
Donghui Li, Yuqing Zhang, Xin Chen, Long Cao
Sina Weibo, as one of the most popular and fast growing social network, has gradually become the field where hot topics appear, propagate, and outbreak. In order to explore and find out the propagating regularity of hot topics on the platform of micro-blog, a novel approach based on a well-known epidemic model called SIR is proposed in this paper to understand and explain hot topics spreading dynamics, which takes the structure information and propagation characteristics of Sina Weibo into consideration. The event of flight MH370 vanished is being used to test the modified topic transmission model based on SIR. The experimental results show that the fitting degree between simulation results and the historical data is high and indicates that there is a high feasibility of this model to research on the propagating regularity of hot topics spreading on Sina Weibo.
{"title":"Propagation regularity of hot topics in Sina Weibo based on SIR model — A simulation research","authors":"Donghui Li, Yuqing Zhang, Xin Chen, Long Cao","doi":"10.1109/ComComAp.2014.7017216","DOIUrl":"https://doi.org/10.1109/ComComAp.2014.7017216","url":null,"abstract":"Sina Weibo, as one of the most popular and fast growing social network, has gradually become the field where hot topics appear, propagate, and outbreak. In order to explore and find out the propagating regularity of hot topics on the platform of micro-blog, a novel approach based on a well-known epidemic model called SIR is proposed in this paper to understand and explain hot topics spreading dynamics, which takes the structure information and propagation characteristics of Sina Weibo into consideration. The event of flight MH370 vanished is being used to test the modified topic transmission model based on SIR. The experimental results show that the fitting degree between simulation results and the historical data is high and indicates that there is a high feasibility of this model to research on the propagating regularity of hot topics spreading on Sina Weibo.","PeriodicalId":422906,"journal":{"name":"2014 IEEE Computers, Communications and IT Applications Conference","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124596182","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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