Pub Date : 2003-03-23DOI: 10.1109/PERCOM.2003.1192721
R. Want, T. Pering
Storage capacity and communication bandwidth are two factors that significantly impact the design and implementation of mobile systems. Furthermore, storage density is increasing at an exponential rate faster than the associated communication bandwidth. High-density storage in very small form factors will enable new classes of applications that would not be possible in systems which rely heavily on communication. These applications, which involve continuous capture, pre-loaded content, and proactive data loading, will help overcome some of the barriers presented to mobile systems. Researchers would be prudent to recognize these trends and better understand how technology growth will impact their research agenda.
{"title":"New horizons for mobile computing","authors":"R. Want, T. Pering","doi":"10.1109/PERCOM.2003.1192721","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192721","url":null,"abstract":"Storage capacity and communication bandwidth are two factors that significantly impact the design and implementation of mobile systems. Furthermore, storage density is increasing at an exponential rate faster than the associated communication bandwidth. High-density storage in very small form factors will enable new classes of applications that would not be possible in systems which rely heavily on communication. These applications, which involve continuous capture, pre-loaded content, and proactive data loading, will help overcome some of the barriers presented to mobile systems. Researchers would be prudent to recognize these trends and better understand how technology growth will impact their research agenda.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122320794","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192773
A. Roy, Soumya K. Das Bhaumik, A. Bhattacharya, K. Basu, D. Cook, Sajal K. Das
The rapid advances in a wide range of wireless access technologies along with the efficient use of smart spaces have already set the stage for the development of smart homes. Context-awareness is perhaps the most salient feature in these intelligent computing platforms. The "location" information of the users plays a vital role in defining this context. To extract the best performance and efficacy of such smart computing environments, one needs a scalable, technology-independent location service. We have developed a predictive framework for location-aware resource optimization in smart homes. The underlying compression mechanism helps in efficient learning of an inhabitant's movement (location) profiles in the symbolic domain. The concept of Asymptotic Equipartition Property (AEP) in information theory helps to predict the inhabitant's future location as well as most likely path-segments with good accuracy. Successful prediction helps in pro-active resource management and on-demand operations of automated devices along the inhabitant's future paths and locations - thus providing the necessary comfort at a near-optimal cost. Simulation results on a typical smart home floor plans corroborate this high prediction success and demonstrate sufficient reduction in daily energy-consumption, manual operations and time spent by the inhabitant which are considered as a fair measure of his/her comfort.
{"title":"Location aware resource management in smart homes","authors":"A. Roy, Soumya K. Das Bhaumik, A. Bhattacharya, K. Basu, D. Cook, Sajal K. Das","doi":"10.1109/PERCOM.2003.1192773","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192773","url":null,"abstract":"The rapid advances in a wide range of wireless access technologies along with the efficient use of smart spaces have already set the stage for the development of smart homes. Context-awareness is perhaps the most salient feature in these intelligent computing platforms. The \"location\" information of the users plays a vital role in defining this context. To extract the best performance and efficacy of such smart computing environments, one needs a scalable, technology-independent location service. We have developed a predictive framework for location-aware resource optimization in smart homes. The underlying compression mechanism helps in efficient learning of an inhabitant's movement (location) profiles in the symbolic domain. The concept of Asymptotic Equipartition Property (AEP) in information theory helps to predict the inhabitant's future location as well as most likely path-segments with good accuracy. Successful prediction helps in pro-active resource management and on-demand operations of automated devices along the inhabitant's future paths and locations - thus providing the necessary comfort at a near-optimal cost. Simulation results on a typical smart home floor plans corroborate this high prediction success and demonstrate sufficient reduction in daily energy-consumption, manual operations and time spent by the inhabitant which are considered as a fair measure of his/her comfort.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":" 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113948314","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192755
G. Pingali, Claudio S. Pinhanez, A. Levas, R. Kjeldsen, Mark Podlaseck, Han Chen, Noi Sukaviriya
This paper introduces a new class of interactive interfaces that can be moved around to appear on ordinary objects and surfaces anywhere in a space. By dynamically adapting the form, function, and location of an interface to suit the context of the user, such steerable interfaces have the potential to offer radically new and powerful styles of interaction in intelligent pervasive computing spaces. We propose defining characteristics of steerable interfaces and present the first steerable interface system that combines projection, gesture recognition, user tracking, environment modeling and geometric reasoning components within a system architecture. Our work suggests that there is great promise and rich potential for further research on steerable interfaces.
{"title":"Steerable interfaces for pervasive computing spaces","authors":"G. Pingali, Claudio S. Pinhanez, A. Levas, R. Kjeldsen, Mark Podlaseck, Han Chen, Noi Sukaviriya","doi":"10.1109/PERCOM.2003.1192755","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192755","url":null,"abstract":"This paper introduces a new class of interactive interfaces that can be moved around to appear on ordinary objects and surfaces anywhere in a space. By dynamically adapting the form, function, and location of an interface to suit the context of the user, such steerable interfaces have the potential to offer radically new and powerful styles of interaction in intelligent pervasive computing spaces. We propose defining characteristics of steerable interfaces and present the first steerable interface system that combines projection, gesture recognition, user tracking, environment modeling and geometric reasoning components within a system architecture. Our work suggests that there is great promise and rich potential for further research on steerable interfaces.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121828499","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192752
A. Bletsas
Time information is critical for a variety of applications in distributed environments that facilitate pervasive computing and communication. This paper describes and evaluates a novel Kalman filtering algorithm for end-to-end time synchronization between a client computer and a server of "true" time (e.g. a GPS source) using messages transmitted over packet switched networks, such as the Internet. The messages exchanged have the NTP format and the algorithm evaluated, is performed only at the client side. The Kalman filtering algorithm is compared to two other techniques widely used, based on linear programming and statistical averaging and the experiments involve independent consecutive measurements (gaussian case) or measurements exhibiting long-range dependence (self-similar case). Performance is evaluated according to the estimation error of frequency offset and time offset between client and server clock, the standard deviation of the estimates and the number of packets used for a specific estimation. The algorithms can exploit existing NTP infrastructure and a specific example is presented.
{"title":"Evaluation of Kalman filtering for network time keeping","authors":"A. Bletsas","doi":"10.1109/PERCOM.2003.1192752","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192752","url":null,"abstract":"Time information is critical for a variety of applications in distributed environments that facilitate pervasive computing and communication. This paper describes and evaluates a novel Kalman filtering algorithm for end-to-end time synchronization between a client computer and a server of \"true\" time (e.g. a GPS source) using messages transmitted over packet switched networks, such as the Internet. The messages exchanged have the NTP format and the algorithm evaluated, is performed only at the client side. The Kalman filtering algorithm is compared to two other techniques widely used, based on linear programming and statistical averaging and the experiments involve independent consecutive measurements (gaussian case) or measurements exhibiting long-range dependence (self-similar case). Performance is evaluated according to the estimation error of frequency offset and time offset between client and server clock, the standard deviation of the estimates and the number of packets used for a specific estimation. The algorithms can exploit existing NTP infrastructure and a specific example is presented.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124542972","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192734
R. Harle, A. Hopper
We present a novel method of extracting topological and metric geographical data using only positional data sensed from personnel movements. We extend research from the field of robotics to cope with the gross nonuniformity of sightings that is characteristic of real people in an indoor environment, and any unintentional obstruction of positioning by the user. We use real data collected using the Bat positioning system installed in the Laboratory for Communication Engineering to present the results of implementing the method. We successfully derive useful information from the data, and suggest further ways in which the techniques described are useful in a ubiquitous, sensor-driven computing environment.
{"title":"Using personnel movements for indoor autonomous environment discovery","authors":"R. Harle, A. Hopper","doi":"10.1109/PERCOM.2003.1192734","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192734","url":null,"abstract":"We present a novel method of extracting topological and metric geographical data using only positional data sensed from personnel movements. We extend research from the field of robotics to cope with the gross nonuniformity of sightings that is characteristic of real people in an indoor environment, and any unintentional obstruction of positioning by the user. We use real data collected using the Bat positioning system installed in the Laboratory for Communication Engineering to present the results of implementing the method. We successfully derive useful information from the data, and suggest further ways in which the techniques described are useful in a ubiquitous, sensor-driven computing environment.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123320088","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192786
K. Bowers, K. Mills, S. Rose
Distributed systems require strategies to detect and recover from failures. Many protocols for distributed systems employ a strategy based on leases, which grant a leaseholder access to data or services for a limited time (the lease period). Choosing an appropriate lease period involves tradeoffs among resource utilization, responsiveness, and system size. We investigate these issues for Jini Network Technology. First, we establish quantitative tradeoffs among lease period, bandwidth utilization, responsiveness, and system size. Then, we consider two self-adaptive algorithms that enable a Jini system, given a fixed allocation of resources, to vary lease periods with system size to achieve the best responsiveness. We compare performance of these self-adaptive algorithms against each other, and against fixed lease periods. We find that one of the self-adaptive algorithms proves easy to implement and performs reasonably well. We anticipate that similar procedures could add self-adaptive capability to other distributed systems that rely on leases.
{"title":"Self-adaptive leasing for jini","authors":"K. Bowers, K. Mills, S. Rose","doi":"10.1109/PERCOM.2003.1192786","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192786","url":null,"abstract":"Distributed systems require strategies to detect and recover from failures. Many protocols for distributed systems employ a strategy based on leases, which grant a leaseholder access to data or services for a limited time (the lease period). Choosing an appropriate lease period involves tradeoffs among resource utilization, responsiveness, and system size. We investigate these issues for Jini Network Technology. First, we establish quantitative tradeoffs among lease period, bandwidth utilization, responsiveness, and system size. Then, we consider two self-adaptive algorithms that enable a Jini system, given a fixed allocation of resources, to vary lease periods with system size to achieve the best responsiveness. We compare performance of these self-adaptive algorithms against each other, and against fixed lease periods. We find that one of the self-adaptive algorithms proves easy to implement and performs reasonably well. We anticipate that similar procedures could add self-adaptive capability to other distributed systems that rely on leases.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115055652","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192750
S. Fischmeister, G. Menkhaus, Alexander Stumpfl
Pervasive computing environments accommodate interconnected and communicating mobile devices. Mobility is a vital aspect of everyday life and technology must offer support for moving users, objects, and devices. Their growing number has strong implications on the bandwidth of wireless and wired networks. Network bandwidth becomes a scare resource and its efficient use is crucial for the quality of service in pervasive computing. In this article we study process models for detecting location changes of moving objects and their effect on the network bandwidth. We simulate a scenario of 10/sup 4/ moving objects for a period of 10/sup 7/ time cycles while monitoring the quality of service with respect to network bandwidth for different location detection strategies. The simulation shows that the class of strategies implementing a synchronous model offers better quality of service than the timed model. We conclude the article with a set of guidelines for the application of the strategies we have investigated.
{"title":"Location-detection strategies in pervasive computing environments","authors":"S. Fischmeister, G. Menkhaus, Alexander Stumpfl","doi":"10.1109/PERCOM.2003.1192750","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192750","url":null,"abstract":"Pervasive computing environments accommodate interconnected and communicating mobile devices. Mobility is a vital aspect of everyday life and technology must offer support for moving users, objects, and devices. Their growing number has strong implications on the bandwidth of wireless and wired networks. Network bandwidth becomes a scare resource and its efficient use is crucial for the quality of service in pervasive computing. In this article we study process models for detecting location changes of moving objects and their effect on the network bandwidth. We simulate a scenario of 10/sup 4/ moving objects for a period of 10/sup 7/ time cycles while monitoring the quality of service with respect to network bandwidth for different location detection strategies. The simulation shows that the class of strategies implementing a synchronous model offers better quality of service than the timed model. We conclude the article with a set of guidelines for the application of the strategies we have investigated.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129146497","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192761
Yoshiyuki Nakamura, Takuichi Nishimura, H. Itoh, H. Nakashima
This paper presents a card type battery-less information terminal $CardBIT - and a method of situated interaction that uses single-lens cameras. The CardBIT system provides situated information support at locations such as exhibition halls, train stations and streets. CardBIT can operate without a battery because it utilizes energy from the information car-tier and the user. It realizes location-and-direction-based interaction; a user can get appropriate information for his/her position and direction. The most significant feature of the CardBIT is its high portability because it is easily implanted into widely-used IC cards. Based on information accumulated in the CardBIT, personalized information in the form of sound, such as speech or music, is provided. Furthermore, a user can signal to the interface system and obtain information dynamically. This paper introduces the CardBIT system concept and its implementation using cameras, position estimation, and sign recognition methods. Our experiments show the feasibility of the proposed system.
{"title":"A system of card type battery-less information terminal: CardBIT for situated interaction","authors":"Yoshiyuki Nakamura, Takuichi Nishimura, H. Itoh, H. Nakashima","doi":"10.1109/PERCOM.2003.1192761","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192761","url":null,"abstract":"This paper presents a card type battery-less information terminal $CardBIT - and a method of situated interaction that uses single-lens cameras. The CardBIT system provides situated information support at locations such as exhibition halls, train stations and streets. CardBIT can operate without a battery because it utilizes energy from the information car-tier and the user. It realizes location-and-direction-based interaction; a user can get appropriate information for his/her position and direction. The most significant feature of the CardBIT is its high portability because it is easily implanted into widely-used IC cards. Based on information accumulated in the CardBIT, personalized information in the form of sound, such as speech or music, is provided. Furthermore, a user can signal to the interface system and obtain information dynamically. This paper introduces the CardBIT system concept and its implementation using cameras, position estimation, and sign recognition methods. Our experiments show the feasibility of the proposed system.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128351270","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192731
R. Headon
This paper describes a system that can observe, recognise and analyse human movements, to provide this awareness to context-aware applications. The movement recognition and characterisation components of this sentient system are described in detail. The system uses the ground reaction force to classify and analyse movements in a non-clinical environment. The signal is classified using statistical pattern recognition. Equipped with knowledge of the movement, characterisation is the process of analysing the ground reaction force to extract parameters of the movement. The components of the movement awareness system operate in a distributed computing environment.
{"title":"Movement awareness for a sentient environment","authors":"R. Headon","doi":"10.1109/PERCOM.2003.1192731","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192731","url":null,"abstract":"This paper describes a system that can observe, recognise and analyse human movements, to provide this awareness to context-aware applications. The movement recognition and characterisation components of this sentient system are described in detail. The system uses the ground reaction force to classify and analyse movements in a non-clinical environment. The signal is classified using statistical pattern recognition. Equipped with knowledge of the movement, characterisation is the process of analysing the ground reaction force to extract parameters of the movement. The components of the movement awareness system operate in a distributed computing environment.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134079371","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 : 2003-03-23DOI: 10.1109/PERCOM.2003.1192759
Danyu Zhu, M. Mutka
Continuous wireless wide area network (WWAN) access for mobile devices in future pervasive systems may be limited by battery power and may generate extensive data telecommunication costs. In this paper we develop a new message notification protocol (MNP) to enable mobile users to maintain a continuous presence at their instant messaging (IM) server while avoiding long, idle connections. In MNP, mobile users cooperatively share a single message notification channel to reduce users' telecommunication charges and extend a device's battery life. A device may turn off its WWAN interface for most of the time to save power, and only needs to contact the IM server when needed. Precise group information does not need to be maintained by a mobile device. Message notification exchanged between the IM server and the peer group is represented by a compressed Bloom filter to further reduce the protocol overhead and provide additional privacy and security.
{"title":"Sharing presence information and message notification in an ad hoc network*","authors":"Danyu Zhu, M. Mutka","doi":"10.1109/PERCOM.2003.1192759","DOIUrl":"https://doi.org/10.1109/PERCOM.2003.1192759","url":null,"abstract":"Continuous wireless wide area network (WWAN) access for mobile devices in future pervasive systems may be limited by battery power and may generate extensive data telecommunication costs. In this paper we develop a new message notification protocol (MNP) to enable mobile users to maintain a continuous presence at their instant messaging (IM) server while avoiding long, idle connections. In MNP, mobile users cooperatively share a single message notification channel to reduce users' telecommunication charges and extend a device's battery life. A device may turn off its WWAN interface for most of the time to save power, and only needs to contact the IM server when needed. Precise group information does not need to be maintained by a mobile device. Message notification exchanged between the IM server and the peer group is represented by a compressed Bloom filter to further reduce the protocol overhead and provide additional privacy and security.","PeriodicalId":230787,"journal":{"name":"Proceedings of the First IEEE International Conference on Pervasive Computing and Communications, 2003. (PerCom 2003).","volume":"238 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122972620","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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