The Experts below are selected from a list of 137691 Experts worldwide ranked by ideXlab platform
Se Woon Choi - One of the best experts on this subject based on the ideXlab platform.
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a wireless mems based inclinometer Sensor Node for structural health monitoring
Sensors, 2013Co-Authors: Dae Woong Ha, Hyo Seon Park, Se Woon ChoiAbstract:This paper proposes a wireless inclinometer Sensor Node for structural health monitoring (SHM) that can be applied to civil engineering and building structures subjected to various loadings. The inclinometer used in this study employs a method for calculating the tilt based on the difference between the static acceleration and the acceleration due to gravity, using a micro-electro-mechanical system (MEMS)-based accelerometer. A wireless Sensor Node was developed through which tilt measurement data are wirelessly transmitted to a monitoring server. This Node consists of a slave Node that uses a short-distance wireless communication system (RF 2.4 GHz) and a master Node that uses a long-distance telecommunication system (code division multiple access—CDMA). The communication distance limitation, which is recognized as an important issue in wireless monitoring systems, has been resolved via these two wireless communication components. The reliability of the proposed wireless inclinometer Sensor Node was verified experimentally by comparing the values measured by the inclinometer and subsequently transferred to the monitoring server via wired and wireless transfer methods to permit a performance evaluation of the wireless communication Sensor Nodes. The experimental results indicated that the two systems (wired and wireless transfer systems) yielded almost identical values at a tilt angle greater than 1°, and a uniform difference was observed at a tilt angle less than 0.42° (approximately 0.0032° corresponding to 0.76% of the tilt angle, 0.42°) regardless of the tilt size. This result was deemed to be within the allowable range of measurement error in SHM. Thus, the wireless transfer system proposed in this study was experimentally verified for practical application in a structural health monitoring system.
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a wireless laser displacement Sensor Node for structural health monitoring
Sensors, 2013Co-Authors: Hyo Seon Park, Se Woon ChoiAbstract:This study describes a wireless laser displacement Sensor Node that measures displacement as a representative damage index for structural health monitoring (SHM). The proposed measurement system consists of a laser displacement Sensor (LDS) and a customized wireless Sensor Node. Wireless communication is enabled by a Sensor Node that consists of a Sensor module, a code division multiple access (CDMA) communication module, a processor, and a power module. An LDS with a long measurement distance is chosen to increase field applicability. For a wireless Sensor Node driven by a battery, we use a power control module with a low-power processor, which facilitates switching between the sleep and active modes, thus maximizing the power consumption efficiency during non-measurement and non-transfer periods. The CDMA mode is also used to overcome the limitation of communication distance, which is a challenge for wireless Sensor networks and wireless communication. To evaluate the reliability and field applicability of the proposed wireless displacement measurement system, the system is tested onsite to obtain the required vertical displacement measurements during the construction of mega-trusses and an edge truss, which are the primary structural members in a large-scale irregular building currently under construction. The measurement values confirm the validity of the proposed wireless displacement measurement system and its potential for use in safety evaluations of structural elements.
Charles R. Farrar - One of the best experts on this subject based on the ideXlab platform.
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Development of an impedance-based wireless Sensor Node for structural health monitoring
Smart Materials and Structures, 2007Co-Authors: David L. Mascarenas, Gyu Hae Park, Michael D. Todd, Charles R. FarrarAbstract:This paper presents the development and application of a miniaturized impedance Sensor Node for structural health monitoring (SHM). A large amount of research has been focused on utilizing the impedance method for structural health monitoring. The vast majority of this research, however, has required the use of expensive and bulky impedance analyzers that are not suitable for field deployment. In this study, we developed a wireless impedance Sensor Node equipped with a low-cost integrated circuit chip that can measure and record the electrical impedance of a piezoelectric transducer, a microcontroller that performs local computing and a wireless telemetry module that transmits the structural information to a base station. The performance of this miniaturized and portable device has been compared to results obtained with a conventional impedance analyzer and its effectiveness has been demonstrated in an experiment to detect loss of preload in a bolted joint. Furthermore, for the first time, we also consider the problem of wireless powering of such SHM Sensor Nodes, where we use radio-frequency wireless energy transmission to deliver electrical energy to power the Sensor Node. In this way, the Sensor Node does not have to rely on an on-board power source, and the required energy can be wirelessly delivered as needed by human or a remotely controlled robotic device.
Drago Zagar - One of the best experts on this subject based on the ideXlab platform.
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javascript virtual web page for wireless Sensor Node under avr microcontroller architecture
Joint IFIP Wireless and Mobile Networking Conference, 2010Co-Authors: Damir Sostaric, Davor Vinko, Drago ZagarAbstract:This paper presents a developed wireless Sensor Node with an embedded JavaScript virtual web page implemented in the AVR microcontroller architecture. The presented design is capable of operating in real-time environment and has an improved performance with respect to the previously developed HTML virtual page. The major advantage of the presented system over the existing ones is the fact that the remote monitoring and control system is fully integrated in the microcontroller. The microcontroller is accessible over the Ethernet and with an integrated virtual web page it can replace the web server commonly used in similar systems. This feature makes the presented design extremely cost effective.
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WMNC - JavaScript virtual web page for wireless Sensor Node under AVR microcontroller architecture
WMNC2010, 2010Co-Authors: Damir Šoštarić, Davor Vinko, Drago ZagarAbstract:This paper presents a developed wireless Sensor Node with an embedded JavaScript virtual web page implemented in the AVR microcontroller architecture. The presented design is capable of operating in real-time environment and has an improved performance with respect to the previously developed HTML virtual page. The major advantage of the presented system over the existing ones is the fact that the remote monitoring and control system is fully integrated in the microcontroller. The microcontroller is accessible over the Ethernet and with an integrated virtual web page it can replace the web server commonly used in similar systems. This feature makes the presented design extremely cost effective.
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Monitoring and Administration of Peripheral Devices Using Wireless Sensor Node
2010Co-Authors: Damir Šoštarić, Krešimir Grgić, Drago ZagarAbstract:This paper describes the implementation of IEEE 802.3 and IEEE 802.11 standards into wireless Sensor Node (WSN1). Such a WSN1 is intended for applications in everyday life. Physical model describes the architecture of microcontroller and Ethernet chip. Sampling time depends the working hours of the WSN. It is implemented in firmware from user which causes central power unit relieved. Connected peripheral devices may be Sensors or actuators that control the analogue or digital environment. Through the virtual page generated from HTML code it is possible to control and monitor measurement value. WSN applications are compared with existing platforms. A possibility of an upgrade exists, towards greater number of analog/digital inputs or digital outputs.
Zhong Lin Wang - One of the best experts on this subject based on the ideXlab platform.
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self powered wireless smart Sensor Node enabled by an ultrastable highly efficient and superhydrophobic surface based triboelectric nanogenerator
ACS Nano, 2016Co-Authors: Kun Zhao, Zhong Lin Wang, Ya YangAbstract:Wireless Sensor networks will be responsible for a majority of the fast growth in intelligent systems in the next decade. However, most of the wireless smart Sensor Nodes require an external power source such as a Li-ion battery, where the labor cost and environmental waste issues of replacing batteries have largely limited the practical applications. Instead of using a Li-ion battery, we report an ultrastable, highly efficient, and superhydrophobic-surface-based triboelectric nanogenerator (TENG) to scavenge wind energy for sustainably powering a wireless smart temperature Sensor Node. There is no decrease in the output voltage and current of the TENG after continuous working for about 14 h at a wind speed of 12 m/s. Through a power management circuit, the TENG can deliver a constant output voltage of 3.3 V and a pulsed output current of about 100 mA to achieve highly efficient energy storage in a capacitor. A wireless smart temperature Sensor Node can be sustainably powered by the TENG for sending the r...
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flow driven triboelectric generator for directly powering a wireless Sensor Node
Advanced Materials, 2015Co-Authors: Shuhua Wang, Ya Yang, Chengliang Sun, Zhong Lin WangAbstract:A triboelectric generator (TEG) for scavenging flow-driven mechanical -energy to directly power a wireless Sensor Node is demonstrated for the first time. The output performances of TEGs with different dimensions are systematically investigated, indicating that a largest output power of about 3.7 mW for one TEG can be achieved under an external load of 3 MΩ.
Hyo Seon Park - One of the best experts on this subject based on the ideXlab platform.
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a wireless mems based inclinometer Sensor Node for structural health monitoring
Sensors, 2013Co-Authors: Dae Woong Ha, Hyo Seon Park, Se Woon ChoiAbstract:This paper proposes a wireless inclinometer Sensor Node for structural health monitoring (SHM) that can be applied to civil engineering and building structures subjected to various loadings. The inclinometer used in this study employs a method for calculating the tilt based on the difference between the static acceleration and the acceleration due to gravity, using a micro-electro-mechanical system (MEMS)-based accelerometer. A wireless Sensor Node was developed through which tilt measurement data are wirelessly transmitted to a monitoring server. This Node consists of a slave Node that uses a short-distance wireless communication system (RF 2.4 GHz) and a master Node that uses a long-distance telecommunication system (code division multiple access—CDMA). The communication distance limitation, which is recognized as an important issue in wireless monitoring systems, has been resolved via these two wireless communication components. The reliability of the proposed wireless inclinometer Sensor Node was verified experimentally by comparing the values measured by the inclinometer and subsequently transferred to the monitoring server via wired and wireless transfer methods to permit a performance evaluation of the wireless communication Sensor Nodes. The experimental results indicated that the two systems (wired and wireless transfer systems) yielded almost identical values at a tilt angle greater than 1°, and a uniform difference was observed at a tilt angle less than 0.42° (approximately 0.0032° corresponding to 0.76% of the tilt angle, 0.42°) regardless of the tilt size. This result was deemed to be within the allowable range of measurement error in SHM. Thus, the wireless transfer system proposed in this study was experimentally verified for practical application in a structural health monitoring system.
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a wireless laser displacement Sensor Node for structural health monitoring
Sensors, 2013Co-Authors: Hyo Seon Park, Se Woon ChoiAbstract:This study describes a wireless laser displacement Sensor Node that measures displacement as a representative damage index for structural health monitoring (SHM). The proposed measurement system consists of a laser displacement Sensor (LDS) and a customized wireless Sensor Node. Wireless communication is enabled by a Sensor Node that consists of a Sensor module, a code division multiple access (CDMA) communication module, a processor, and a power module. An LDS with a long measurement distance is chosen to increase field applicability. For a wireless Sensor Node driven by a battery, we use a power control module with a low-power processor, which facilitates switching between the sleep and active modes, thus maximizing the power consumption efficiency during non-measurement and non-transfer periods. The CDMA mode is also used to overcome the limitation of communication distance, which is a challenge for wireless Sensor networks and wireless communication. To evaluate the reliability and field applicability of the proposed wireless displacement measurement system, the system is tested onsite to obtain the required vertical displacement measurements during the construction of mega-trusses and an edge truss, which are the primary structural members in a large-scale irregular building currently under construction. The measurement values confirm the validity of the proposed wireless displacement measurement system and its potential for use in safety evaluations of structural elements.
