In our contribution, we analyze case studies on the storage of additional data on tag in RFID applications. We identify four basic functions which are pursued by the data-on-tag concept. The results of our analysis provide insight into what benefits can be achieved through the use of data-on-tag applications, which technology is necessary and why a data-on- network approach would fail in most of the analyzed cases.
{"title":"Beyond EPC - Insights from Multiple RFID Case Studies on the Storage of Additional Data on Tag","authors":"A. Melski, L. Thoroe, T. Caus, M. Schumann","doi":"10.1109/WASA.2007.144","DOIUrl":"https://doi.org/10.1109/WASA.2007.144","url":null,"abstract":"In our contribution, we analyze case studies on the storage of additional data on tag in RFID applications. We identify four basic functions which are pursued by the data-on-tag concept. The results of our analysis provide insight into what benefits can be achieved through the use of data-on-tag applications, which technology is necessary and why a data-on- network approach would fail in most of the analyzed cases.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130991419","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}
A. Vießmann, A. Burnic, C. Spiegel, G. Bruck, P. Jung
This paper will give a detailed discussion about the authors view on software defined and cognitive radio. After an introduction on different aspects of software radio and a novel approach on cognitive radio is presented. As proof of concept a software defined cognitive radio demonstrator termed Falcon was built up which is described afterwards. The Falcon is entirely based on a modular signal processing concept. In particular, the receiver deploys modules which process and generate log-likelihood ratio (LLR) signals, hence, providing the capability of a plug-and-play-type reconfigurability.
{"title":"A novel Cognitive Radio Concept deploying Petri Net based Scheduling","authors":"A. Vießmann, A. Burnic, C. Spiegel, G. Bruck, P. Jung","doi":"10.1109/WASA.2007.136","DOIUrl":"https://doi.org/10.1109/WASA.2007.136","url":null,"abstract":"This paper will give a detailed discussion about the authors view on software defined and cognitive radio. After an introduction on different aspects of software radio and a novel approach on cognitive radio is presented. As proof of concept a software defined cognitive radio demonstrator termed Falcon was built up which is described afterwards. The Falcon is entirely based on a modular signal processing concept. In particular, the receiver deploys modules which process and generate log-likelihood ratio (LLR) signals, hence, providing the capability of a plug-and-play-type reconfigurability.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114741271","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}
Wireless sensor networks receive lots of attention due to its promising techniques and wide-ranging applications in recent years. The kind of network occasionally becomes disconnected due to initial uneven deployments or unpredictable failures or run out of battery of sensor nodes. However, sensor nodes with mobility then can be used in an addition deployment to reconnect the disconnected sensor networks. Theoretically, the augmenting geometric graph problem is defined here to model this kind of connectivity issues. The work proposes two novel algorithms: the graph-oriented algorithm and the divide-and-conquer algorithm to connect disconnected networks by using as less as possible mobile nodes. The first algorithm highly exploits traditional graph and geometry techniques including Fermat point, convex hull, nearest neighbor, minimum cost spanning tree, and graph contraction. Adopting a quite different approach, the second algorithm resolves the problem by dividing the deployed area and merging sub-solutions recursively. With respect to complexity issue, the graph-oriented algorithm takes 0(n3) time; on the other hand, the divide-and-conquer algorithm requires 0(n log n) time, where n is the size of vertex set of the given graph G=(V, E). These proposed two algorithms have low time complexity and can be implemented in a centralized sensor network.
{"title":"Deploying Mobile Nodes to Connect Wireless Sensor Networks Using Novel Algorithms","authors":"Chang Wu, Yu, Elvis Chen, Chun-Cheng Fang","doi":"10.1109/WASA.2007.62","DOIUrl":"https://doi.org/10.1109/WASA.2007.62","url":null,"abstract":"Wireless sensor networks receive lots of attention due to its promising techniques and wide-ranging applications in recent years. The kind of network occasionally becomes disconnected due to initial uneven deployments or unpredictable failures or run out of battery of sensor nodes. However, sensor nodes with mobility then can be used in an addition deployment to reconnect the disconnected sensor networks. Theoretically, the augmenting geometric graph problem is defined here to model this kind of connectivity issues. The work proposes two novel algorithms: the graph-oriented algorithm and the divide-and-conquer algorithm to connect disconnected networks by using as less as possible mobile nodes. The first algorithm highly exploits traditional graph and geometry techniques including Fermat point, convex hull, nearest neighbor, minimum cost spanning tree, and graph contraction. Adopting a quite different approach, the second algorithm resolves the problem by dividing the deployed area and merging sub-solutions recursively. With respect to complexity issue, the graph-oriented algorithm takes 0(n3) time; on the other hand, the divide-and-conquer algorithm requires 0(n log n) time, where n is the size of vertex set of the given graph G=(V, E). These proposed two algorithms have low time complexity and can be implemented in a centralized sensor network.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123212328","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}
Wireless environments are typically characterized by unpredictable and unreliable channel conditions. In such environments, fragmentation of network-bound data is a commonly adapted technique to improve the probability of successful data transmissions and reduce the energy overheads incurred due to re-transmissions. The overall latencies involved with fragmentation and consequent re-assembly of fragments are often neglected which bear significant effects on the real-time guarantees of the participating applications. This work studies the latencies introduced as a result of the fragmentation performed at the link layer (MAC layer in IEEE 802.11) of the source device and their effects on end-to-end delay constraints of mobile applications (e.g., media streaming). Based on the observed effects, this work proposes a feedback-based adaptive approach that chooses an optimal fragment size to (a) satisfy end-to-end delay requirements of the distributed application and (b) minimize the energy consumption of the source device by increasing the probability of successful transmissions, thereby reducing re-transmissions and their associated costs.
{"title":"Adaptive Fragmentation for Latency Control and Energy Management in Wireless Real-time Environments","authors":"D. Rajan, C. Poellabauer","doi":"10.1109/WASA.2007.140","DOIUrl":"https://doi.org/10.1109/WASA.2007.140","url":null,"abstract":"Wireless environments are typically characterized by unpredictable and unreliable channel conditions. In such environments, fragmentation of network-bound data is a commonly adapted technique to improve the probability of successful data transmissions and reduce the energy overheads incurred due to re-transmissions. The overall latencies involved with fragmentation and consequent re-assembly of fragments are often neglected which bear significant effects on the real-time guarantees of the participating applications. This work studies the latencies introduced as a result of the fragmentation performed at the link layer (MAC layer in IEEE 802.11) of the source device and their effects on end-to-end delay constraints of mobile applications (e.g., media streaming). Based on the observed effects, this work proposes a feedback-based adaptive approach that chooses an optimal fragment size to (a) satisfy end-to-end delay requirements of the distributed application and (b) minimize the energy consumption of the source device by increasing the probability of successful transmissions, thereby reducing re-transmissions and their associated costs.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128301797","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}
We study how to select and arrange multiple types of wireless sensors to build a star network that meets the coverage, the lifetime, the fault-tolerance, and the minimum-cost requirements, where the network lifetime, the acceptable failure probability of the network, and the failure rate of each type of sensors are given as parameters. This problem is NP-hard. We model this problem as an integer linear programming minimization problem. We then present an efficient approximation algorithm to find a feasible solution to the problem, which provides a sensor arrangement and a scheduling. We show that, through numerical experiments, our approximation provides solutions with approximation ratios less than 1.4.
{"title":"Fault-Tolerant Sensor Coverage for Achieving Wanted Coverage Lifetime with Minimum Cost","authors":"Zhijun Yu, Jie Wang","doi":"10.1109/WASA.2007.22","DOIUrl":"https://doi.org/10.1109/WASA.2007.22","url":null,"abstract":"We study how to select and arrange multiple types of wireless sensors to build a star network that meets the coverage, the lifetime, the fault-tolerance, and the minimum-cost requirements, where the network lifetime, the acceptable failure probability of the network, and the failure rate of each type of sensors are given as parameters. This problem is NP-hard. We model this problem as an integer linear programming minimization problem. We then present an efficient approximation algorithm to find a feasible solution to the problem, which provides a sensor arrangement and a scheduling. We show that, through numerical experiments, our approximation provides solutions with approximation ratios less than 1.4.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"337 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133048527","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}
In this paper, we study the geographic collaborative forwarding (GCF) scheme, a variant of opportunistic routing, which exploits the broadcast nature and spatial diversity of the wireless medium to improve the packet delivery efficiency. Our goal is to fully understand the principles, the gains, and the tradeoffs of the node collaboration and its associated cost, thus provide insightful analysis and guidance to the design of more efficient routing/forwarding protocols. We first identify the upper bound of the expected packet advancement (EPA) that GCF can achieve and prove the concavity of the maximum EPA. With energy efficiency as a major concern, we propose a new metric, EPA per unit energy consumption, which balances the packet advancement, reliability and energy consumption. By leveraging the proved properties, we then propose an efficient algorithm which selects a feasible candidate set that maximizes this local metric. We validate our analysis results by simulations, and justify the effectiveness of the new metric by comparing the performance of GCF with those of the existing geographic and opportunistic routing schemes.
{"title":"On Geographic Collaborative Forwarding in Wireless Ad Hoc and Sensor Networks","authors":"K. Zeng, W. Lou, Jie Yang, D.R. Brown","doi":"10.1109/WASA.2007.121","DOIUrl":"https://doi.org/10.1109/WASA.2007.121","url":null,"abstract":"In this paper, we study the geographic collaborative forwarding (GCF) scheme, a variant of opportunistic routing, which exploits the broadcast nature and spatial diversity of the wireless medium to improve the packet delivery efficiency. Our goal is to fully understand the principles, the gains, and the tradeoffs of the node collaboration and its associated cost, thus provide insightful analysis and guidance to the design of more efficient routing/forwarding protocols. We first identify the upper bound of the expected packet advancement (EPA) that GCF can achieve and prove the concavity of the maximum EPA. With energy efficiency as a major concern, we propose a new metric, EPA per unit energy consumption, which balances the packet advancement, reliability and energy consumption. By leveraging the proved properties, we then propose an efficient algorithm which selects a feasible candidate set that maximizes this local metric. We validate our analysis results by simulations, and justify the effectiveness of the new metric by comparing the performance of GCF with those of the existing geographic and opportunistic routing schemes.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116522684","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}
Multicast routing for wireless networks has been widely studied in the literature. In this paper, we design efficient algorithm for maximizing multicast throughput in wireless networks. We assume that we are given a set of wireless devices. All wireless devices are assumed to have the uniform (or quasi-uniform) transmission ranges and have the uniform interference range (or quasi-uniform interference range). We further assume that each wireless node Vi will have a capacity Wi when no interference occurred during its transmission and it can transmit continuously. We present an efficient routing and node scheduling algorithms such that the achieved multicast capacity is within a constant factor of the optimum. Our theoretical throughput performance guarantees are proved under a various number interference models.
{"title":"Maximizing throughput multicast routing forwireless networks","authors":"Xiangyang Li, Yanwei Wu","doi":"10.1109/WASA.2007.75","DOIUrl":"https://doi.org/10.1109/WASA.2007.75","url":null,"abstract":"Multicast routing for wireless networks has been widely studied in the literature. In this paper, we design efficient algorithm for maximizing multicast throughput in wireless networks. We assume that we are given a set of wireless devices. All wireless devices are assumed to have the uniform (or quasi-uniform) transmission ranges and have the uniform interference range (or quasi-uniform interference range). We further assume that each wireless node Vi will have a capacity Wi when no interference occurred during its transmission and it can transmit continuously. We present an efficient routing and node scheduling algorithms such that the achieved multicast capacity is within a constant factor of the optimum. Our theoretical throughput performance guarantees are proved under a various number interference models.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116523094","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}
In this paper, we present an iterated algorithm framework that can be implemented with heuristics in the literature for the minimum energy broadcasting problem in wireless ad hoc networks. We investigate three iterated algorithm implementations, IBIP, IOMEGa, ISOR, that are based on BIP, OMEGa, SOR. The algorithms run iterations to find better solutions of the problem and in each iteration, fixing the source node's transmission power, the algorithm finds the intermediate solutions. And after all the iterations, the algorithm will give the output of the best solution so far. By fixing the source node's transmission power we can get the effect of diverse solution search without hurting the original algorithm's theoretical performance bound. The experimental results confirm that the iterated algorithms significantly improve the solution quality with the help of diverse search.
{"title":"Iterated Algorithms for the Minimum Energy Broadcast Tree Problem in Wireless Ad Hoc Networks","authors":"Manki Min","doi":"10.1109/WASA.2007.71","DOIUrl":"https://doi.org/10.1109/WASA.2007.71","url":null,"abstract":"In this paper, we present an iterated algorithm framework that can be implemented with heuristics in the literature for the minimum energy broadcasting problem in wireless ad hoc networks. We investigate three iterated algorithm implementations, IBIP, IOMEGa, ISOR, that are based on BIP, OMEGa, SOR. The algorithms run iterations to find better solutions of the problem and in each iteration, fixing the source node's transmission power, the algorithm finds the intermediate solutions. And after all the iterations, the algorithm will give the output of the best solution so far. By fixing the source node's transmission power we can get the effect of diverse solution search without hurting the original algorithm's theoretical performance bound. The experimental results confirm that the iterated algorithms significantly improve the solution quality with the help of diverse search.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114695971","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}
In this paper, multiuser waterfilling theory applied to subcarrier and power allocation in orthogonal frequency division multiplexing (OFDM) system is researched. Note that the traditional scheduling algorithm making use of the channel status information(CSI) feedback needs broad control channel to transfer the frequent CSI in multipath Rayleigh fast fading channel, which is often impractical or inefficient, we propose a resource allocation algorithm based on tap correlation information(TCOI), which is characterized by channel statistical information. The algorithm is designed to utilize the TCOI to reduce the channel feedback. Because the optimal resolution is high nonlinear, we convert the proposed algorithm into discrete method to achieve lower algorithm complexity. The simulation result shows that the proposed algorithm has tiny reduction in overall system capacity, but much lower complexity of algorithm and small channel feedback comparing to the traditional scheduling algorithm based on CSI, what's more it outperforms greatly channel independent scheduling basing on pathless in fast Rayleigh fading channel.
{"title":"A New Subcarrier and Power Allocation Algorithm Based on Statistical Information in Multiuser OFDM System","authors":"Xuebing Pei, Guangxi Zhu, Gan Liu","doi":"10.1109/WASA.2007.135","DOIUrl":"https://doi.org/10.1109/WASA.2007.135","url":null,"abstract":"In this paper, multiuser waterfilling theory applied to subcarrier and power allocation in orthogonal frequency division multiplexing (OFDM) system is researched. Note that the traditional scheduling algorithm making use of the channel status information(CSI) feedback needs broad control channel to transfer the frequent CSI in multipath Rayleigh fast fading channel, which is often impractical or inefficient, we propose a resource allocation algorithm based on tap correlation information(TCOI), which is characterized by channel statistical information. The algorithm is designed to utilize the TCOI to reduce the channel feedback. Because the optimal resolution is high nonlinear, we convert the proposed algorithm into discrete method to achieve lower algorithm complexity. The simulation result shows that the proposed algorithm has tiny reduction in overall system capacity, but much lower complexity of algorithm and small channel feedback comparing to the traditional scheduling algorithm based on CSI, what's more it outperforms greatly channel independent scheduling basing on pathless in fast Rayleigh fading channel.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128649936","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}
Quorum systems are well-known techniques designed to enhance the performance of distributed systems, such as to reduce the access cost per operation, to balance the load, and to improve the system scalability. All of these properties make quorum systems particularly attractive for large- scale sensor applications involving coordinated tasks, such as rescue applications. In this paper we analyze quorum techniques in the specific context of sensor networks and energy conservation, and show why quorum systems designed for wired networks and their metrics fail to address the challenges introduced by sensor networks. We then redefine quorum metrics such as access cost, load balance, and capacity in a way that takes into account the limitations and the characteristics of sensor networks, and discuss some energy-efficient design strategies. In addition, we propose a family of energy-efficient quorum systems and a particular construction, called Regional quorum system (RQ), which reduces the quorum access cost. Finally, we propose a data diffusion protocol built on top of the RQ system, which improves energy consumption by reducing message transmissions and collisions, and increases the available bandwidth. We apply our diffusion protocol to analyze the RQ system using our novel metrics.
{"title":"Revising Quorum Systems for Energy Conservation in Sensor Networks","authors":"D. Tulone, E. Demaine","doi":"10.1109/WASA.2007.84","DOIUrl":"https://doi.org/10.1109/WASA.2007.84","url":null,"abstract":"Quorum systems are well-known techniques designed to enhance the performance of distributed systems, such as to reduce the access cost per operation, to balance the load, and to improve the system scalability. All of these properties make quorum systems particularly attractive for large- scale sensor applications involving coordinated tasks, such as rescue applications. In this paper we analyze quorum techniques in the specific context of sensor networks and energy conservation, and show why quorum systems designed for wired networks and their metrics fail to address the challenges introduced by sensor networks. We then redefine quorum metrics such as access cost, load balance, and capacity in a way that takes into account the limitations and the characteristics of sensor networks, and discuss some energy-efficient design strategies. In addition, we propose a family of energy-efficient quorum systems and a particular construction, called Regional quorum system (RQ), which reduces the quorum access cost. Finally, we propose a data diffusion protocol built on top of the RQ system, which improves energy consumption by reducing message transmissions and collisions, and increases the available bandwidth. We apply our diffusion protocol to analyze the RQ system using our novel metrics.","PeriodicalId":316831,"journal":{"name":"International Conference on Wireless Algorithms, Systems and Applications (WASA 2007)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134357126","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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