Pub Date : 2006-04-10DOI: 10.1109/ISWPC.2006.1613591
I. Kim, Min-seop Jeong, C. Kang
A Directional Border Flooding (DBF) scheme is a practical means of solving the broadcast storm problem in Mobile Ad Hoc Networks (MANET), by dealing with a cross layer design of medium access control and network routing processes. In this paper, a new type of patching scheme, Selective Rebroadcast Suppression (SRS) is proposed, in order to reduce unreachable nodes, which govern the overall network reliability in the directional border flooding process. This system determines a group of relay nodes in a distributive manner, to enable a patching scheme to be selectively applied for those that are essential for reliable flooding. The simulation results demonstrate that the proposed SRS patching scheme provides a flexible yet robust method of reducing unnecessary flooding overhead, as much as 32 % when compared with the existing patching scheme, and while maintaining a given level of Route Failure Rate (RFR) performance.
{"title":"Selective Rebroadcast Suppression (SRS) Scheme for Directional Border Flooding in Mobile Ad Hoc Networks","authors":"I. Kim, Min-seop Jeong, C. Kang","doi":"10.1109/ISWPC.2006.1613591","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613591","url":null,"abstract":"A Directional Border Flooding (DBF) scheme is a practical means of solving the broadcast storm problem in Mobile Ad Hoc Networks (MANET), by dealing with a cross layer design of medium access control and network routing processes. In this paper, a new type of patching scheme, Selective Rebroadcast Suppression (SRS) is proposed, in order to reduce unreachable nodes, which govern the overall network reliability in the directional border flooding process. This system determines a group of relay nodes in a distributive manner, to enable a patching scheme to be selectively applied for those that are essential for reliable flooding. The simulation results demonstrate that the proposed SRS patching scheme provides a flexible yet robust method of reducing unnecessary flooding overhead, as much as 32 % when compared with the existing patching scheme, and while maintaining a given level of Route Failure Rate (RFR) performance.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126372934","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613577
W. Karner, O. Nemethova, M. Rupp
3GPP specifications allow to change the physical resources allocated to the users dynamically to optimize the radio resource utilization in UMTS. Network operators can make use of this optimization feature by properly adjusting dynamic bearer type switching in their networks. In this paper we show an analysis of the dynamic bearer type switching based on measurements in a live UMTS network in the city center of Vienna, Austria. Particularly, we present the usage probability and the runlength distribution of the three different radio access bearers which are used for transmission over the UMTS DCH (dedicated channel) packet switched (PS) domain in DL (down link), namely 384 kbit/s, 128 kbit/s and 64 kbit/s bearer. For the performance evaluation of applications, system level simulators are used, where the lower layers are usually represented via stochastic models. Following the measured statistics we develop a model capable of properly describing the dynamic switching between the mentioned bearers. Furthermore, we show that a four-state Markov model with its geometrically distributed runlengths does not provide sufficient accuracy. We achieve an enhancement by using a four-state renewal process with Weibull distributed runlengths as presented in this document.
{"title":"A measurement based model for UMTS DL DCH dynamic bearer type switching","authors":"W. Karner, O. Nemethova, M. Rupp","doi":"10.1109/ISWPC.2006.1613577","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613577","url":null,"abstract":"3GPP specifications allow to change the physical resources allocated to the users dynamically to optimize the radio resource utilization in UMTS. Network operators can make use of this optimization feature by properly adjusting dynamic bearer type switching in their networks. In this paper we show an analysis of the dynamic bearer type switching based on measurements in a live UMTS network in the city center of Vienna, Austria. Particularly, we present the usage probability and the runlength distribution of the three different radio access bearers which are used for transmission over the UMTS DCH (dedicated channel) packet switched (PS) domain in DL (down link), namely 384 kbit/s, 128 kbit/s and 64 kbit/s bearer. For the performance evaluation of applications, system level simulators are used, where the lower layers are usually represented via stochastic models. Following the measured statistics we develop a model capable of properly describing the dynamic switching between the mentioned bearers. Furthermore, we show that a four-state Markov model with its geometrically distributed runlengths does not provide sufficient accuracy. We achieve an enhancement by using a four-state renewal process with Weibull distributed runlengths as presented in this document.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128186529","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613610
K. Hida, M. Mizutani, T. Miyamaru, H. Mineno, N. Miyauchi, T. Mizuno
Determining the physical location of indoor objects is a key issue in ubiquitous computing. Although there have been many proposals to provide physical location, these have had several restrictions such as dependence on the type and size of objects and trade-offs between location accuracy and the number of sensing devices. We propose an approach to removing these restrictions using mobile detectors. This paper describes the design of a goods tracking system called MobiTra that estimates the locations of any indoor objects using detection histories sent by mobile detectors. MobiTra is separated by several components and two data flows. A prototype for MobiTra was developed using an active RF system and Cricket, which can obtain a high degree of accuracy. We evaluated how accurately MobiTra estimated location in an environment that generated MTR errors. The errors affected the size of the estimated area and its position. We propose a new method of estimating location to be used in environments that generate MTR errors.
{"title":"Design of goods tracking system with mobile detectors","authors":"K. Hida, M. Mizutani, T. Miyamaru, H. Mineno, N. Miyauchi, T. Mizuno","doi":"10.1109/ISWPC.2006.1613610","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613610","url":null,"abstract":"Determining the physical location of indoor objects is a key issue in ubiquitous computing. Although there have been many proposals to provide physical location, these have had several restrictions such as dependence on the type and size of objects and trade-offs between location accuracy and the number of sensing devices. We propose an approach to removing these restrictions using mobile detectors. This paper describes the design of a goods tracking system called MobiTra that estimates the locations of any indoor objects using detection histories sent by mobile detectors. MobiTra is separated by several components and two data flows. A prototype for MobiTra was developed using an active RF system and Cricket, which can obtain a high degree of accuracy. We evaluated how accurately MobiTra estimated location in an environment that generated MTR errors. The errors affected the size of the estimated area and its position. We propose a new method of estimating location to be used in environments that generate MTR errors.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128187565","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613632
F. Diamantopoulos, A. Economides
Wireless adhoc sensor networks are ad hoc networks that consist of a number of autonomous, battery powered, static devices, communicating with each other through radio connections, using special routing algorithms. Many sensor network implementations use DSDV as their routing protocol. The wireless sensor networks' resources such as throughput and energy are scarce and need to be carefully used. Power control can be implemented by CLUSTERPOW algorithm. Among other factors that could waste the networks' resources and deplete the nodes' energy, is the routing protocol's overhead. DSDV is designed for mobile ad hoc networks and a large ratio of its traffic is generated to keep the routes updated. We studied the behavior of the protocols through simulation and found out that by carefully adjusting some parameters the performance improves, the routing overhead reduces and less energy is consumed.
{"title":"A performance study of DSDV-based CLUSTERPOW and DSDV routing algorithms for sensor network applications","authors":"F. Diamantopoulos, A. Economides","doi":"10.1109/ISWPC.2006.1613632","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613632","url":null,"abstract":"Wireless adhoc sensor networks are ad hoc networks that consist of a number of autonomous, battery powered, static devices, communicating with each other through radio connections, using special routing algorithms. Many sensor network implementations use DSDV as their routing protocol. The wireless sensor networks' resources such as throughput and energy are scarce and need to be carefully used. Power control can be implemented by CLUSTERPOW algorithm. Among other factors that could waste the networks' resources and deplete the nodes' energy, is the routing protocol's overhead. DSDV is designed for mobile ad hoc networks and a large ratio of its traffic is generated to keep the routes updated. We studied the behavior of the protocols through simulation and found out that by carefully adjusting some parameters the performance improves, the routing overhead reduces and less energy is consumed.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130472916","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613618
P. Pakdeepaiboonpol, S. Kittitornkun
Most compiler optimization techniques concern most about speed. In this paper, we present two high-level power/energy optimization methods for ARM-based battery-powered embedded multimedia systems, e.g. mobile phones, pocket PCs, personal multimedia systems, etc. The experiments using MPEG-4 simple profile level 0 (SP@L0) video encoder on ARM920T with two QCIF video sequences 15 fps, 24 kbps show that the proposed techniques can complement the existing speed-oriented ones to achieve lower energy/power consumption up to 5.7% relative to all ARM C++ optimization levels despite the 16-KB instruction and 16-KB data caches of ARM 920T core.
{"title":"Low energy optimization for MPEG-4 video encoder on ARM-based mobile phones","authors":"P. Pakdeepaiboonpol, S. Kittitornkun","doi":"10.1109/ISWPC.2006.1613618","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613618","url":null,"abstract":"Most compiler optimization techniques concern most about speed. In this paper, we present two high-level power/energy optimization methods for ARM-based battery-powered embedded multimedia systems, e.g. mobile phones, pocket PCs, personal multimedia systems, etc. The experiments using MPEG-4 simple profile level 0 (SP@L0) video encoder on ARM920T with two QCIF video sequences 15 fps, 24 kbps show that the proposed techniques can complement the existing speed-oriented ones to achieve lower energy/power consumption up to 5.7% relative to all ARM C++ optimization levels despite the 16-KB instruction and 16-KB data caches of ARM 920T core.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132874591","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613579
F. Wegscheider
Presence is an always-on service. This means that even when the user does not need presence information about his buddies, his mobile phone gets updates about their state. These updates use bandwidth on the radio network and - even more important - drain the mobile terminal's battery. This paper suggests ways to reduce these updates within the presence part of the 3G IP multimedia subsystem (IMS) while maintaining full responsiveness of the presence service for the end user. We propose and compare three solutions to the problem. They extend the interface between the resource list server and the mobile terminal. Our methods minimize traffic on the air interface while maintaining full responsiveness for the end user. They are transparent to the presence server and the presentities, the only entities needing adaptations are the client on the user terminal and the resource list server.
{"title":"Minimizing unnecessary notification traffic in the IMS presence system","authors":"F. Wegscheider","doi":"10.1109/ISWPC.2006.1613579","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613579","url":null,"abstract":"Presence is an always-on service. This means that even when the user does not need presence information about his buddies, his mobile phone gets updates about their state. These updates use bandwidth on the radio network and - even more important - drain the mobile terminal's battery. This paper suggests ways to reduce these updates within the presence part of the 3G IP multimedia subsystem (IMS) while maintaining full responsiveness of the presence service for the end user. We propose and compare three solutions to the problem. They extend the interface between the resource list server and the mobile terminal. Our methods minimize traffic on the air interface while maintaining full responsiveness for the end user. They are transparent to the presence server and the presentities, the only entities needing adaptations are the client on the user terminal and the resource list server.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133173502","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613652
C. Charng, Wen-Ching Lo, Lin-Fei Sung, Shyh-In Hwang
In wireless ad hoc networks, broadcasting is widely used by routing protocols to disseminate link/node state information or route discovery requests. However, broadcasting by blind flooding is highly energy-intensive and may involve serious redundancy, contention, and collision known as a broadcast storm problem. In this paper, two schemes are proposed to improve broadcasting performance and energy consumption called fair energy-efficient flooding and probabilistic energy-efficient flooding respectively. Both schemes periodically perform a fully localized average-based diffusion algorithm to estimate the average network energy (ANE). Scheme I utilizes ANE to decide whether to forward a broadcast message or not. Scheme II uses probabilistic rebroadcasting by referring to ANE. Our simulation results show different levels of improvement as compared with related approaches.
{"title":"EDAB: energy-efficient diffusion algorithm for broadcast in wireless ad hoc networks","authors":"C. Charng, Wen-Ching Lo, Lin-Fei Sung, Shyh-In Hwang","doi":"10.1109/ISWPC.2006.1613652","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613652","url":null,"abstract":"In wireless ad hoc networks, broadcasting is widely used by routing protocols to disseminate link/node state information or route discovery requests. However, broadcasting by blind flooding is highly energy-intensive and may involve serious redundancy, contention, and collision known as a broadcast storm problem. In this paper, two schemes are proposed to improve broadcasting performance and energy consumption called fair energy-efficient flooding and probabilistic energy-efficient flooding respectively. Both schemes periodically perform a fully localized average-based diffusion algorithm to estimate the average network energy (ANE). Scheme I utilizes ANE to decide whether to forward a broadcast message or not. Scheme II uses probabilistic rebroadcasting by referring to ANE. Our simulation results show different levels of improvement as compared with related approaches.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121376498","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613582
Sungho Kim, Sunshin An
In order to provide fast handover, lots of micro-mobility protocols have been designed and proposed. However, they may cause excessive signal traffic and long latency for handover management. This paper proposes a new routing algorithm for micro-mobility scheme using core node. Core node handles routing information for a mobile host. It does not need to generate unnecessary control messages at each base station and wired node. We have conducted distribution of traffic as messages which create at the old BS and then disappears at the core node for maintenance of the routing table. We have evaluated the performance of our micro-mobility scheme through a series of simulations using the network simulator 2 (ns-2).
{"title":"A new routing algorithm for micro-mobility by using core node","authors":"Sungho Kim, Sunshin An","doi":"10.1109/ISWPC.2006.1613582","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613582","url":null,"abstract":"In order to provide fast handover, lots of micro-mobility protocols have been designed and proposed. However, they may cause excessive signal traffic and long latency for handover management. This paper proposes a new routing algorithm for micro-mobility scheme using core node. Core node handles routing information for a mobile host. It does not need to generate unnecessary control messages at each base station and wired node. We have conducted distribution of traffic as messages which create at the old BS and then disappears at the core node for maintenance of the routing table. We have evaluated the performance of our micro-mobility scheme through a series of simulations using the network simulator 2 (ns-2).","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125384169","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613655
Joon Heo, C. Hong
Generally sensor network and wireless ad hoc network use a symmetric key agreement scheme, although this mechanism has some problems, such as key management, complex network deployment and configuration. This is because the devices of sensor network have limitations such as power, memory, processor speed and implementation cost. The public key algorithms are considered to be too expensive in term of memory and processing requirements. In Low-Rate Wireless Personal Area Network (WPAN), we propose a new key agreement mechanism using the Security Manager (SM) for public key management based on the EC-MQV algorithm. And also, we define two security levels by means of device's power and security policies in the network. We have measured the performance of this mechanism and at the same time meeting the low implementation cost and low power.
{"title":"Efficient and Authenticated Key Agreement Mechanism in Low-Rate WPAN Environment","authors":"Joon Heo, C. Hong","doi":"10.1109/ISWPC.2006.1613655","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613655","url":null,"abstract":"Generally sensor network and wireless ad hoc network use a symmetric key agreement scheme, although this mechanism has some problems, such as key management, complex network deployment and configuration. This is because the devices of sensor network have limitations such as power, memory, processor speed and implementation cost. The public key algorithms are considered to be too expensive in term of memory and processing requirements. In Low-Rate Wireless Personal Area Network (WPAN), we propose a new key agreement mechanism using the Security Manager (SM) for public key management based on the EC-MQV algorithm. And also, we define two security levels by means of device's power and security policies in the network. We have measured the performance of this mechanism and at the same time meeting the low implementation cost and low power.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130619848","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 : 2006-04-10DOI: 10.1109/ISWPC.2006.1613631
H. Hemmati, M. Niamanesh, R. Jalili
With the increasing use of pervasive computing environments (PCEs), developing dynamic reconfigurable software in such environments becomes an important issue. The ability to change software components in running systems has advantages such as building adaptive, long-life, and self-reconfigurable software as well as increasing invisibility in PCEs. As dynamic reconfiguration is performed in error-prone wireless mobile systems frequently, it can threaten system safety. Therefore, a mechanism to support assured dynamic reconfiguration at run-time for PCEs is required. In this paper, we propose an assured dynamic reconfiguration framework (ADRF) with emphasis on assurance analysis. The framework is implemented and is available for further research. To evaluate the framework, an abstract case study including reconfigurations has been applied using our own developed simulator for PCEs. Our experience shows that ADRF properly preserves reconfiguration assurance.
{"title":"A framework to support run-time assured dynamic reconfiguration for pervasive computing environments","authors":"H. Hemmati, M. Niamanesh, R. Jalili","doi":"10.1109/ISWPC.2006.1613631","DOIUrl":"https://doi.org/10.1109/ISWPC.2006.1613631","url":null,"abstract":"With the increasing use of pervasive computing environments (PCEs), developing dynamic reconfigurable software in such environments becomes an important issue. The ability to change software components in running systems has advantages such as building adaptive, long-life, and self-reconfigurable software as well as increasing invisibility in PCEs. As dynamic reconfiguration is performed in error-prone wireless mobile systems frequently, it can threaten system safety. Therefore, a mechanism to support assured dynamic reconfiguration at run-time for PCEs is required. In this paper, we propose an assured dynamic reconfiguration framework (ADRF) with emphasis on assurance analysis. The framework is implemented and is available for further research. To evaluate the framework, an abstract case study including reconfigurations has been applied using our own developed simulator for PCEs. Our experience shows that ADRF properly preserves reconfiguration assurance.","PeriodicalId":145728,"journal":{"name":"2006 1st International Symposium on Wireless Pervasive Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122293543","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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