Existing research on sensor data management mostly addresses issues minted to querying sensor measures. However, withthe multitude of sensor-based applications, "device management" needs are emerging. Such ...
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ISBN:
(纸本)9784907764319
Existing research on sensor data management mostly addresses issues minted to querying sensor measures. However, withthe multitude of sensor-based applications, "device management" needs are emerging. Such operations modify properties of sensors, update their software or configure them. this paper concerns the impact of management operations on con. current continuous queries. this issue has not yet been explored and is important for reliable support or large scale heterogeneous sensorsystems. We propose a finer view of continuous queries and a mechanism allowing their concurrent execution with update operations. Experimental results show that our mechanism adds very little overhead to continuous query execution.
Time synchronization is essential in sensor network applications such as object tracking, consistent state updates, duplicate detection and temporal order delivery. In addition, reliability issues and fault tolerance ...
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ISBN:
(纸本)9784907764319
Time synchronization is essential in sensor network applications such as object tracking, consistent state updates, duplicate detection and temporal order delivery. In addition, reliability issues and fault tolerance in sophisticated sensor networks have become a critical area of research today. this paper proposes a Lightweight Fault Tolerant Time Synchronization (LFTTS), an extension of Fault Tolerant Time Synchronization (FTTS), for wireless sensor networks which takes their energy limitations and faults into consideration. Simulation results show that LFTTS has improved performance in the number of messages when faults occur.
this paper describes a wireless camera node with passive pendulum mechanism. We focus on transferring captured movie via wireless network and easy setting-up operation at demonstration site.
ISBN:
(纸本)9784907764319
this paper describes a wireless camera node with passive pendulum mechanism. We focus on transferring captured movie via wireless network and easy setting-up operation at demonstration site.
this demonstration proposal describes a database system for ubiquitous sensor networks, KRAFT. KRAFT has three remarkable features: real-time monitoring, pattern recognition and fast data storing. As for real-time mon...
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ISBN:
(纸本)9784907764319
this demonstration proposal describes a database system for ubiquitous sensor networks, KRAFT. KRAFT has three remarkable features: real-time monitoring, pattern recognition and fast data storing. As for real-time monitoring, KRAFT adjusts invocation times of continual queries control user level thread scheduler. As for pattern recognition, KRAFT provides analytical sliding window functions and sequence matching functions.
In this paper, we propose a MEMS vibrating sensing system for application to networked sensing systems and discuss simulation results. A MEMS vibrating sensor is excited by optical pulses from an optical fiber connect...
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ISBN:
(纸本)9784907764319
In this paper, we propose a MEMS vibrating sensing system for application to networked sensing systems and discuss simulation results. A MEMS vibrating sensor is excited by optical pulses from an optical fiber connected to a loser diode. the vibration velocity of the sensor is detected by optical Doppler measurement with another laser diode and photodiode. the optical pulse frequency is tuned to the resonant frequency of the MEMS sensor based on the optical Doppler measurement result. the resonant frequency of this vibrating sensor can reflect physical quantities such as temperature, pressure, and gas density. the main features of the sensing system are its ability to be used as an isolated sensor with no electronic circuit or power supply and its ability to sense multiple points by connecting sensors of different resonance frequencies to one optical fiber in parallel.
the purpose of this research was to develop a method for automatically detecting gross errors of networkedsensors and re-calibrating the corresponding sensors. A sensor network system consists of huge number of senso...
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ISBN:
(纸本)9784907764319
the purpose of this research was to develop a method for automatically detecting gross errors of networkedsensors and re-calibrating the corresponding sensors. A sensor network system consists of huge number of sensors. It is not easy to calibrate each of these sensors manually. Hence, such a system needs a method for detecting gross errors partly caused by malfunctions of the sensors, in order to keep its reliability high. In this poster, we show an automatic calibration method based on the maximum-likelihood estimation and its application to gross error detection.
In wireless sensor networks, the data aggregation is an essential paradigm for routing, through which the multiple data from different sensors can be aggregated into a single data at intermedial nodes enroute, in orde...
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ISBN:
(纸本)9780769532875
In wireless sensor networks, the data aggregation is an essential paradigm for routing, through which the multiple data from different sensors can be aggregated into a single data at intermedial nodes enroute, in order to eliminate data redundancy and achieve the goal of saving energy. Some existed medium access protocols and algorithms can effectively prolong the lifetime of the sensor network by determining when each sensor should transmit its data, and when it should sleep. In this paper, we focus on applying multiple spanning trees to organize the data aggregation, which is different from these existed single spanning tree methods. At first, the problem of constructing multiple spanning trees is transformed into a linear programming problem of the data flow network. Based on the solved optimal rate between the two adjacent sensors, the two constructing algorithms of the spanning tree are presented. Experimental results indicate that the method of multiple spanning trees can be of benefit to energy saving for wireless sensor networks, and the corresponding appropriate constructing algorithm can prolong the lifetime of the sensor network.
Recent years have seen active development of context-aware applications and systemsthat helps the development. However, it suffers from increasing fears for leakages of users' activity information to other users ...
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ISBN:
(纸本)9784907764319
Recent years have seen active development of context-aware applications and systemsthat helps the development. However, it suffers from increasing fears for leakages of users' activity information to other users unconsciously, since the owner of the activity information included in the sensor data is not treated in context-aware systems. We propose the Area-Based Activity Information Preservation (ABAIP) system that enables users to control the level of data resolution of their activity information to allow applications to use. Degrading sensor data resolution causes coarse grained context recognition. the system prevents unconscious and unnecessary activity information leakage amongst the ABAIP system users, while providing ubiquitous sensor environment for various kinds of ubiquitous software.
Wireless sensor Networks are fundamentally limited by their energy storage resources and the power they obtain from their environment. Several micro-solar powered designs have been developed to address this important ...
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ISBN:
(纸本)9784907764319
Wireless sensor Networks are fundamentally limited by their energy storage resources and the power they obtain from their environment. Several micro-solar powered designs have been developed to address this important problem but little analysis is available on key design trade-offs. We develop a taxonomy of the micro-solar design space identifying key components, design choices, Interactions, challenges, and trade-offs. Based on this taxonomy, we provide an empirical and mathematical analysis of two prominent designs of micro-solar power systems (Heliomote and Trio), and interpret the results to propose design guidelines for micro-solar power systems.
this paper discusses a wireless sensor node with impact resistance capability. We have been discussing the development of disaster information gathering system utilizing wireless sensor network deployed by rescue robo...
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ISBN:
(纸本)9784907764319
this paper discusses a wireless sensor node with impact resistance capability. We have been discussing the development of disaster information gathering system utilizing wireless sensor network deployed by rescue robots for underground facility such as metro station. For convenient and efficient deployment of A sensor network, we proposed throwing deployment method. To realize throwing deployment, we developed a wireless sensor node with impact resistance capability for withstanding landing impact. An impact resistance capability and throughput of communication of sensor nodes were confirmed.
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