Pub Date : 2005-07-11DOI: 10.1109/PERSER.2005.1506560
Zikuan Liu, J. Almhana, V. Choulakian, R. McGorman
The challenges of providing data services over wireless networks come from, their high reliability requirement under noisy wireless channels. In this paper, we model the noisy channel by a continuous-time Markov process and propose a dynamical packet transmission strategy for data service. The transmission strategy optimization is formulated as a Markov decision process. We establish that the optimal strategy has a threshold structure and develop a single sample path-based optimization algorithm to tune the thresholds. Since only a single sample path is involved, the proposed algorithm can be implemented online.
{"title":"Online optimal data transmission strategy under Markov channel","authors":"Zikuan Liu, J. Almhana, V. Choulakian, R. McGorman","doi":"10.1109/PERSER.2005.1506560","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506560","url":null,"abstract":"The challenges of providing data services over wireless networks come from, their high reliability requirement under noisy wireless channels. In this paper, we model the noisy channel by a continuous-time Markov process and propose a dynamical packet transmission strategy for data service. The transmission strategy optimization is formulated as a Markov decision process. We establish that the optimal strategy has a threshold structure and develop a single sample path-based optimization algorithm to tune the thresholds. Since only a single sample path is involved, the proposed algorithm can be implemented online.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130965491","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506402
J. Broensted, K. M. Hansen, L. Kristensen
The LIWAS traffic warning system aims at providing early warning to vehicles about road conditions, such as whether the road is slippery. The LIWAS system is currently being developed and consists of two main parts: sensors for determining the state of the road and a communication infrastructure supporting inter-vehicle communication. This paper presents our results on requirements identification, design, and prototyping of the infrastructure. The infrastructure combines communication via mobile phones with communication based on the principles of ad-hoc networking, and it supports units in being updated during operation. The presented prototypes and associated experimental results demonstrate the main functionalities of the communication infrastructure, and have led to the initial deployment of LIWAS units.
{"title":"An infrastructure for a traffic warning system","authors":"J. Broensted, K. M. Hansen, L. Kristensen","doi":"10.1109/PERSER.2005.1506402","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506402","url":null,"abstract":"The LIWAS traffic warning system aims at providing early warning to vehicles about road conditions, such as whether the road is slippery. The LIWAS system is currently being developed and consists of two main parts: sensors for determining the state of the road and a communication infrastructure supporting inter-vehicle communication. This paper presents our results on requirements identification, design, and prototyping of the infrastructure. The infrastructure combines communication via mobile phones with communication based on the principles of ad-hoc networking, and it supports units in being updated during operation. The presented prototypes and associated experimental results demonstrate the main functionalities of the communication infrastructure, and have led to the initial deployment of LIWAS units.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123565762","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506569
R. Baldoni, J. Hélary, S. Piergiovanni
In the context of mobile ad-hoc networks, this paper studies the problem of reliable communication among a set of processes forming a group in a dynamic system with an unbounded number of processes. A communication is reliable if any message sent by a member of the group that never leaves or leaves the group in an intentional way is eventually delivered to every member that doesn't leave the group. The problem is studied in a setting where communication links model a temporary disconnection among group members. The paper shows that additional assumptions on the system model are necessary to assure reliable communication. Then it presents a protocol, based on these assumptions, solving the problem in a meeting/conference room application scenario.
{"title":"Group communication in ad-hoc networks: a few results and a case study","authors":"R. Baldoni, J. Hélary, S. Piergiovanni","doi":"10.1109/PERSER.2005.1506569","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506569","url":null,"abstract":"In the context of mobile ad-hoc networks, this paper studies the problem of reliable communication among a set of processes forming a group in a dynamic system with an unbounded number of processes. A communication is reliable if any message sent by a member of the group that never leaves or leaves the group in an intentional way is eventually delivered to every member that doesn't leave the group. The problem is studied in a setting where communication links model a temporary disconnection among group members. The paper shows that additional assumptions on the system model are necessary to assure reliable communication. Then it presents a protocol, based on these assumptions, solving the problem in a meeting/conference room application scenario.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129441264","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506404
T. Nakajima
In our daily lives, we have several personal devices carried with us everyday like a mobile phone. These devices contain more functionalities than now, and it is important to consider what these devices can do in the future. For example, these personal devices may be used to coordinate various appliances near a user. This paper proposes a personal coordination server that allows a user to control various information appliances near the user spontaneously. The personal coordination server personalizes the coordination of information appliances in several ways. The personalization can be used to design a user's experience. Our approach embeds preference rules that personalize the coordination among appliance into everyday artefacts such as seals, pens or keys. A user closes and departs the everyday artefacts to/from his/her personal devices to personalize the coordination explicitly. Also a designer embeds preference rules in cups and stuffed animals that a user uses in his/her daily activities or our surrounding environments to design the coordination for the user.
{"title":"Personal coordination server: a system infrastructure for designing pleasurable experience","authors":"T. Nakajima","doi":"10.1109/PERSER.2005.1506404","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506404","url":null,"abstract":"In our daily lives, we have several personal devices carried with us everyday like a mobile phone. These devices contain more functionalities than now, and it is important to consider what these devices can do in the future. For example, these personal devices may be used to coordinate various appliances near a user. This paper proposes a personal coordination server that allows a user to control various information appliances near the user spontaneously. The personal coordination server personalizes the coordination of information appliances in several ways. The personalization can be used to design a user's experience. Our approach embeds preference rules that personalize the coordination among appliance into everyday artefacts such as seals, pens or keys. A user closes and departs the everyday artefacts to/from his/her personal devices to personalize the coordination explicitly. Also a designer embeds preference rules in cups and stuffed animals that a user uses in his/her daily activities or our surrounding environments to design the coordination for the user.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129207481","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506391
Li Zhou, C. Ravishankar
Sensor networks frequently deploy many tiny and inexpensive devices over large regions to detect events of interest. It can be easy to compromise sensors, enabling attackers to use the keys and other information stored at the sensors to inject false reports, forging fake events. Existing approaches do not localize the impact of such node compromises, so that compromises in one sensing region may compromise other parts of the system. In this paper, we propose two fault localized schemes for false report filtering. In our basic scheme, sensors signal events using one-way hash chains, which allows en-route nodes to verify the authenticity of received reports based on commitments of detecting sensors, but prevents them from forging events. We extend this basic scheme to a collaborative filtering scheme using commitment predistribution, making it more adaptable for mobile sensor networks and high-density sensor networks. Our scheme can also provide localized protection for areas that require special protection. Our security analysis shows that our schemes can offer stronger security protection than existing schemes, and are efficient.
{"title":"A fault localized scheme for false report filtering in sensor networks","authors":"Li Zhou, C. Ravishankar","doi":"10.1109/PERSER.2005.1506391","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506391","url":null,"abstract":"Sensor networks frequently deploy many tiny and inexpensive devices over large regions to detect events of interest. It can be easy to compromise sensors, enabling attackers to use the keys and other information stored at the sensors to inject false reports, forging fake events. Existing approaches do not localize the impact of such node compromises, so that compromises in one sensing region may compromise other parts of the system. In this paper, we propose two fault localized schemes for false report filtering. In our basic scheme, sensors signal events using one-way hash chains, which allows en-route nodes to verify the authenticity of received reports based on commitments of detecting sensors, but prevents them from forging events. We extend this basic scheme to a collaborative filtering scheme using commitment predistribution, making it more adaptable for mobile sensor networks and high-density sensor networks. Our scheme can also provide localized protection for areas that require special protection. Our security analysis shows that our schemes can offer stronger security protection than existing schemes, and are efficient.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127101351","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506547
Rachid Saadi, J. Pierson, L. Brunie
The main future challenge of pervasive computing consists in offering access anywhere and anytime with any devices. However, before it becomes a reality, the problems of access control and authentication have to be solved, among others. Existing solutions are inadequate without adaptation to this specific environment. Among the promising approaches, the trust paradigm seems to be more flexible than others. We base this proposal on this paradigm to implement a distrust model, so-called APC (access pass certificate). The main objective of this model is to enable authorized user to roam and to access trusted hosts without being known locally. Each user can have an APC certificate from two kinds of hosts: the main host (where the user is member) and the trusted host (that trusts the user). Using these certificates, the user extends progressively his access scope. Moreover, this model implements a decentralized mapping policy, where correspondence between the user's home profile and its rights on the trusted hosts is determined as needed. This distrust model and its implementation are presented in this article where we exhibit its interests for large but controlled access in pervasive environments.
{"title":"APC: access pass certificate distrust certification model for large access in pervasive environment","authors":"Rachid Saadi, J. Pierson, L. Brunie","doi":"10.1109/PERSER.2005.1506547","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506547","url":null,"abstract":"The main future challenge of pervasive computing consists in offering access anywhere and anytime with any devices. However, before it becomes a reality, the problems of access control and authentication have to be solved, among others. Existing solutions are inadequate without adaptation to this specific environment. Among the promising approaches, the trust paradigm seems to be more flexible than others. We base this proposal on this paradigm to implement a distrust model, so-called APC (access pass certificate). The main objective of this model is to enable authorized user to roam and to access trusted hosts without being known locally. Each user can have an APC certificate from two kinds of hosts: the main host (where the user is member) and the trusted host (that trusts the user). Using these certificates, the user extends progressively his access scope. Moreover, this model implements a decentralized mapping policy, where correspondence between the user's home profile and its rights on the trusted hosts is determined as needed. This distrust model and its implementation are presented in this article where we exhibit its interests for large but controlled access in pervasive environments.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128130545","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 : 2005-07-11DOI: 10.1108/17427370580000136
Kiran Modukari, S. Hariri, N. Chalfoun, Mazin S. Yousif
Programming sensor networks currently is a subtle task not because of enormous amount of code but due to inherent limitations of embedded hardware like the power, memory, network bandwidth and clock speed. In addition, there are very few programming abstractions and standards available which lead to close coupling between the application code and the embedded OS requiring understanding of low-level primitives during implementation. A middleware can provide glue code between the applications and the heterogeneity of devices by providing optimized set of services for autonomously managing the resources and functionality of wireless nodes in a distributed wireless sensor network. This paper presents an autonomous middleware framework for low power distributed wireless sensor networks that support adaptive sensor functionality, context aware communications, clustering, quality of service and fault-tolerance. Finally an application on how to use the autonomous middleware is illustrated on the envelope system research apparatus (ESRA).
{"title":"Autonomous middleware framework for sensor networks","authors":"Kiran Modukari, S. Hariri, N. Chalfoun, Mazin S. Yousif","doi":"10.1108/17427370580000136","DOIUrl":"https://doi.org/10.1108/17427370580000136","url":null,"abstract":"Programming sensor networks currently is a subtle task not because of enormous amount of code but due to inherent limitations of embedded hardware like the power, memory, network bandwidth and clock speed. In addition, there are very few programming abstractions and standards available which lead to close coupling between the application code and the embedded OS requiring understanding of low-level primitives during implementation. A middleware can provide glue code between the applications and the heterogeneity of devices by providing optimized set of services for autonomously managing the resources and functionality of wireless nodes in a distributed wireless sensor network. This paper presents an autonomous middleware framework for low power distributed wireless sensor networks that support adaptive sensor functionality, context aware communications, clustering, quality of service and fault-tolerance. Finally an application on how to use the autonomous middleware is illustrated on the envelope system research apparatus (ESRA).","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133991289","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506392
Yi Ouyang, Zhengyi Le, J. Ford, F. Makedon
Sensor networks are playing a more and more important role in monitoring problems such as surveillance and tracking moving objects. In-network processing has been shown to improve scalability, prolong sensor network lifetimes, and diminish computational demands. However, securely querying past data becomes a challenge. An unimportant event in the past could become interesting later; therefore, methods for securely placing a query on a past event should be available. This paper focuses on the challenges associated with securing queries on past data in a sensor network, and proposes methods for past data aggregation using in-network processing. Two different methods are proposed for securing queries on past data; both use forward secure cryptography and provide forward secure data authentication. We compare their security and performance, and also compare them with previous schemes.
{"title":"Local data protection for in-network processing in sensor networks","authors":"Yi Ouyang, Zhengyi Le, J. Ford, F. Makedon","doi":"10.1109/PERSER.2005.1506392","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506392","url":null,"abstract":"Sensor networks are playing a more and more important role in monitoring problems such as surveillance and tracking moving objects. In-network processing has been shown to improve scalability, prolong sensor network lifetimes, and diminish computational demands. However, securely querying past data becomes a challenge. An unimportant event in the past could become interesting later; therefore, methods for securely placing a query on a past event should be available. This paper focuses on the challenges associated with securing queries on past data in a sensor network, and proposes methods for past data aggregation using in-network processing. Two different methods are proposed for securing queries on past data; both use forward secure cryptography and provide forward secure data authentication. We compare their security and performance, and also compare them with previous schemes.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131327648","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506420
U. Meissen, S. Pfennigschmidt, A. Voisard, Tjark Wahnfried
Demand-orientation is of crucial importance in mobile and pervasive information services in order to ensure the delivery of the right information at the right time and at the right place. Increasing attention has been devoted to the notion of personalized services that take the situation of the user into account. The trade-off is to ensure appropriate information supply while preventing information overload. Comparing situations predicted by the system with the expectations of a user yields information about "so-far-unexpected" changes the user should be informed about. This paper describes an approach to support situation-awareness and introduces an underlying model that additionally handles information from various sources. Our approach is illustrated in a driving assistance application.
{"title":"Matching system knowledge and user expectations in situation-aware systems","authors":"U. Meissen, S. Pfennigschmidt, A. Voisard, Tjark Wahnfried","doi":"10.1109/PERSER.2005.1506420","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506420","url":null,"abstract":"Demand-orientation is of crucial importance in mobile and pervasive information services in order to ensure the delivery of the right information at the right time and at the right place. Increasing attention has been devoted to the notion of personalized services that take the situation of the user into account. The trade-off is to ensure appropriate information supply while preventing information overload. Comparing situations predicted by the system with the expectations of a user yields information about \"so-far-unexpected\" changes the user should be informed about. This paper describes an approach to support situation-awareness and introduces an underlying model that additionally handles information from various sources. Our approach is illustrated in a driving assistance application.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131157593","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 : 2005-07-11DOI: 10.1109/PERSER.2005.1506424
B. Chandramouli, H. Lei, K. Bhaskaran, Henry Chang, M. Dikun, F. Heath
This paper presents the design and implementation of the Puma middleware system. Puma enables pervasive access to Web applications from a wide range of clients. In addition to traditional, browser-equipped client devices such as laptops and PDAs, Puma supports the use of peer collaboration tools such as instant messengers, SMS devices, email clients and telephones. While those collaboration tools were initially intended for free-form interaction between people, Puma leverages them for structured interaction between people and computers in order to offer more flexibility, convenience and intimacy to end users. In addition to user-initiated, or pull-based, interactions, Puma allows an application to proactively push an interaction to a user, in a manner sensitive to the application's needs and the user's current context. Architecturally, Puma employs various Modality Bots to mediate between application servers and heterogeneous clients. The Modality Bots also serve as the initial point of contact for application-initiated interactions. As an experiment, Puma has been used to mobilize the human tasks application, which supports the creation, processing, and management of the manual steps in business processes.
{"title":"Pushing the envelope of pervasive access","authors":"B. Chandramouli, H. Lei, K. Bhaskaran, Henry Chang, M. Dikun, F. Heath","doi":"10.1109/PERSER.2005.1506424","DOIUrl":"https://doi.org/10.1109/PERSER.2005.1506424","url":null,"abstract":"This paper presents the design and implementation of the Puma middleware system. Puma enables pervasive access to Web applications from a wide range of clients. In addition to traditional, browser-equipped client devices such as laptops and PDAs, Puma supports the use of peer collaboration tools such as instant messengers, SMS devices, email clients and telephones. While those collaboration tools were initially intended for free-form interaction between people, Puma leverages them for structured interaction between people and computers in order to offer more flexibility, convenience and intimacy to end users. In addition to user-initiated, or pull-based, interactions, Puma allows an application to proactively push an interaction to a user, in a manner sensitive to the application's needs and the user's current context. Architecturally, Puma employs various Modality Bots to mediate between application servers and heterogeneous clients. The Modality Bots also serve as the initial point of contact for application-initiated interactions. As an experiment, Puma has been used to mobilize the human tasks application, which supports the creation, processing, and management of the manual steps in business processes.","PeriodicalId":375822,"journal":{"name":"ICPS '05. Proceedings. International Conference on Pervasive Services, 2005.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125400279","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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