• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.2
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• pp.488-494
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• 2013

For the activeness and autonomy of a sensor network, the efficient migration method of a mobile agent and the consistent naming services are the required components of a sensor network. Accordingly, this paper presented the implementation of backward migration of an active rule mobile agent applying the naming method based on RMI that used the meta_table including the informations about the components of a sensor network. This study implemented based on the extension of the forward migration[12], and the results of the various experiments present the efficacy of mobile agent middleware system and the possibility of constructing efficient sensor network application environment. And, the results of this study are able to enhance the adaptability on dynamic changes of environment in sensor network application development.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3128-3132
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• 2010

A disposable solid-state pH sensor was realized by utilizing two nanoporous Pt (npPt) electrodes and a copolyelectrolytic junction. One nanoporous Pt electrode was to measure the pH as an indicating electrode (pH-IE) and the other assembled with copolyelectrolytic junction was to maintain constant open circuit potential ($E_{oc}$) as a solid-state reference electrode (SSRE). The copolyelectrolytic junction was composed of cationic and anionic polymers immobilized by photo-polymerization of N,N'-methylenebisacrylamide, making buffered electrolytic environment on the SSRE. It was expected to make. The nanoporous Pt surrounded by a constant pH excellently worked as a solid state reference electrode so as to stabilize the system within 30 s and retain the electrochemical environment regardless of unknown sample solutions. Combination between the SSRE and the pH-IE commonly based on nanoporous Pt yielded a complete solid-state pH sensor that requires no internal filling solution. The solid state pH sensing chip is simple and easy to fabricate so that it could be practically used for disposable purposes. Moreover, the solid-state pH sensor successfully functions in calibration-free mode in a variety of buffers and surfactant samples.

• Journal of Sensor Science and Technology
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• v.28 no.1
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• pp.64-70
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• 2019

Wireless sensors have been developed in numerous ways for enhancing the convenience of installation, management and maintenance of sensors. Energy harvesting wireless sensors, which can collect energy from the external environment for permanent usage without the need of recharging and exchanging batteries, have been developed and employed used in Internet of Things and at various industrial sites. Energy harvesting wireless sensors are significantly affected by the sensor lifespan to sudden variation in the external environment. Furthermore, reduction in the sensor operating timespan can greatly affect the characteristics of the devices connected through a network. In this paper, a system performance index is proposed that can comprehensively evaluate the lifespan of a solar cell wireless sensor, determine the characteristics of devices connected to the associated network, and recommend dynamic power distribution control for improving the system performance index. Improvement in the system performance index was verified by applying the proposed dynamic power distribution control to an air conditioner network system using a solar cell wireless sensor. Obtained results corroborate that the dynamic power distribution control can extend the lifespan of the incorporated wireless sensor and reduce the air conditioner's power consumption.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.6
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• pp.1175-1186
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• 2020

In this study, the problem is analyzed, and methods of improvement are presented. For evaluating the performance of the proposed EGT sensor, a complex environment test equipment has been developed to test both high temperature and vibration conditions at the same time. This equipment evaluates the accuracy and response time of the EGT sensor. In the results of the comparison test of the complex environment test equipment of heat and vibration, the existing sensor showed a carbonization problem, and the proposed sensor showed no problem. Therefore, it is expected that the improved EGT sensor will be able to be applied to various industrial fields, including gas turbines for power generation.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.1
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• pp.191-196
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• 2021

In this paper, we implemented an image sensor module possible of detecting color temperature in an indoor environment. The color temperature information in the video information acquired by the image sensor was matched with a color difference illuminometer to produce an LUT. An algorithm was developed so that color temperature information according to the received RGB values can be automatically calculated. As a result of measuring the color temperature with an image sensor indoors, an accurate result of less than 5.91% was obtained compared to the reference value. It was confirmed that the uniformity of 23.5% or more was excellent compared to the color temperature measurement result using a color sensor.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.423-423
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• 2000

This paper proposes an effective algorithm for following a wall by an autonomous mobile robot with sonar sensors and infrared sensors in an indoor environment. The proposed method uses deadreckoning to estimate the current position and orientation of a mobile robot. Sonar sensor data are used to estimate shape and position of wall using proposed algorithm. Infrared sensor data are used as assistant when sonar sensor data is uncertain. Simulation results using mobile robot show that the proposed algorithm is proper for the following wall.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1676-1677
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• 2007

본 논문에서는 유비쿼터스 환경 구성을 위해 필수불가결한 센서노드인 Sensor Platform을 설계하고 제작하였다. 개발된 Sensor Platform은 상위로는 Ethernet 통신, 하위로는 여러 가지 센서와의 다양한 인터페이스를 제공한다. 개발된 Sensor Platform을 사용한 예를 보이고 그 타당성을 보였다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.5
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• pp.65-71
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• 2009

As a core area of the new computing paradigm, the Ubiquitous Sensor Network Technology utilizes a wireless sensor networking which can be applied to the Context Information Monitoring System. When the technology is used in a poor user-environment for monitoring purposes, it can cost-effectively gather the context data on real-time basis, analyze the information gathered, effectively response to the user situation, and execute orders to create environmental factors desired by the user. This study structures a system able to monitor information in regards to a user-environment based on wireless-node sensor technology coupled with the Ubiquitous Sensor Network Technology. In this paper, the protocol in which it manages the wireless sensor network as the zone based by using the management protocol standardized at the smart home with a profile is proposed. The proposed system requires a minimal collection of data without continuous monitoring. Monitoring periodically, it can sense the user-environment more efficiently than the existing monitoring technologies based on the wire-communication technology.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.4
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• pp.69-75
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• 2010

In this paper, a ZigBee-based wireless sensor network is configured for the robot to effectively communicate with the environment platform where sensor nodes are implemented using high performance microcontrollers. The localization and the navigation functions are also required to the robot which performs the given task using various types of sensor information. A new type of ZigBee stack is developed using the RUM(Router Under MAC) of the Atmel Corp. and it is applied to a 32-bit ARM core microcontroller for the high performance sensor data manipulation and transmission. It is verified by experiments that the wireless sensor network consisting of developed high performance sensor nodes can be effectively used for the robot environment platform.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.357-360
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• 2008

Vital sign monitoring system using IEEE 502.IS.4 based wireless sensor network(WSN) is designed and developed on mobile environment and sensor node platform. WSN and CDMA are integrated to create a wide coverage to support various environments like inside and outside. We developed query processor to use selective any devices(ECG, Blood pressure and sugar module) and control of the self-organizing network of sensor nodes in a wireless sensor network. Vital sign from wireless medical any devices are analysed in cell phone first for real time signal analyses and the abnormal vital signs are sent and save to hospital server for detail signal processing. wireless signal traffic in wireless sensor network environment or data communication inside the cell phone is reduced.