• Journal of the Korean Geosynthetics Society
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• v.13 no.3
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• pp.1-10
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• 2014

Several types of methods such as resistivity survey, ground penetration radar, etc are used for detection of levee leakage and according to the river design guidelines detection of levee leakage is performed by measuring the hydraulic conductivity of levee soil. But, the former can not verify the leakage point and degree of saturation, the latter is an after treatment method. Movable sensor, which is a high-tech TDR system developed since 2000, can obtain directly the dielectric constant profile covering the whole depth of levee. In this study, laboratory and field model experiments were carried out using movable TDR sensor in order to evaluate the applicability as detection system of levee leakage, As the result, movable TDR system has proven to be 3 times more sensitive to water contents than dry unit weight, and the results conclude that the dielectric constant, water contents and density of the ground proved to have a correlation among them, and the dielectric constant is expected to be a basic data on detection of levee leakage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.119-120
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• 2023

This paper investigates the applicability of movable sensors that can be attached to hard hats to protect construction site safety management to prevent safety accidents based on accident case studies in the field of construction engineering and the gas sensors currently used in construction sites. We would like to propose MQ-2, a standard Arduino gas sensor.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.1
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• pp.85-92
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• 2005

The motion of flexseal bearing for movable nozzle has inherent nonlinear characteristics due to floating rotational center and compression by combustion pressure of solid motor. To perform precise attitude control in spite of these characteristics, the TVC actuation system requires counter potentiometer as an extra position feedback sensor of movable nozzle to form a compensated control loop. The prototype TVC actuation system, test equipments and compensated controller are newly designed, manufactured and tested in consideration of counter potentiometer. On the basis of integration test, the inherent characteristics of movable nozzle and control characteristics of its TVC actuation system are analyzed and summarized in this paper.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.236-238
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• 2002

A noble fiberoptic voltage sensor system utilizing an interferometric transducer has been introduced for high voltage measurement. The sensor system employs a fiberoptic Fabry-Perot interferometric strain sensor to convert voltage to displacement in an auxiliary movable electrode. The operating mechanism is based on the fact that the electrostatic force acting on the electrode system by the applied voltage results in strain variation on the Fabry-Perot interferometry. The experiment results show that the proposed voltage sensor has the potential to be extended to very high voltage system with appropriate auxiliary electrodes.

• International journal of advanced smart convergence
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• v.5 no.1
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• pp.1-7
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• 2016

Recently, introduced a cloud computing technology to the IT industry, smart phones, it has become possible connection between mobility terminal such as a tablet PC. For dissemination and popularization of movable wireless terminal, the same operation have focused on a viable mobile cloud in various terminal. Also, it evolved Wireless Sensor Network(WSN) technology, utilizing a Body Sensor Network(BSN), which research is underway to build large Ubiquitous Sensor Network(USN). BSN is based on large-scale sensor networks, it integrates the state information of the patient's body, it has been the need to build a managed system. Also, by transferring the acquired sensor information to HIS(Hospital Information System), there is a need to frequently monitor the condition of the patient. Therefore, In this paper, possible sensor information exchange between terminals in a mobile cloud environment, by integrating the data obtained by the body sensor HIS and interoperable data DBaaS (DataBase as a Service) it will provide a base of mBodyCloud System. Therefore, to provide an integrated protocol to include the sensor data to a standard HL7(Health Level7) medical information data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.438-439
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• 2011

Magnetic levitation control system of a metal ball was designed using combined PID and fuzzy logic, in which two electromagnets are used to control the vertical and horizontal position of the ball. Single synchronization coil sensor was used to detect the vertical position. Electric power is differentially supplied to two electromagnets so that the ball can move horizontally. In the experiment 25 cm diameter metal ball was levitated and successfully controlled to move horizontally.

• Transactions on Electrical and Electronic Materials
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• v.7 no.4
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• pp.184-188
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• 2006

This work describes efforts in the fabrication and testing of robust microelectromechanical systems (MEMS). Robustness is typically achieved by investigating non-silicon substrates and materials for MEMS fabrication. Some of the traditional MEMS fabrication techniques are applicable to robust MEMS, while other techniques are drawn from other technology areas, such as electronic packaging. The fabrication technologies appropriate for robust MEMS are illustrated through laminated polymer membrane based pressure sensor arrays. Each array uses a stainless steel substrate, a laminated polymer film as a suspended movable plate, and a fixed, surface micromachined back electrode of electroplated nickel. Over an applied pressure range from 0 to 34 kPa, the net capacitance change was approximately 0.14 pF. An important attribute of this design is that only the steel substrate and the pressure sensor inlet is exposed to the flow; i.e., the sensor is self-packaged.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.3
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• pp.285-290
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• 2016

In rural area, our farmers confront decreasing benefits owing to imported crops and increased cost. Recently, the government encourage the 6th Industry that merges farming, rural resources, and information and communication technology. Therefor the government makes an investment in supplying 'smart greenhouse' in which a farmer monitor growing crops and environment information to control growing condition. The objective of this study is developing an Moving Monitor and Control System for crops in green House. This system includes a movable sensing unit, a controlling unit, and a server PC unit. The movable sensing unit contains high resolution IP camera, temperature and humidity sensor and WiFi repeater. It rolls on a rail hanging beneath the ceiling of a green house. The controlling unit contains embedded PC, PLC module, WiFi router, and BLDC motor to drive the movable sensing unit. And the server PC unit contains a integrated farm management software and home pages and databases in which the images of crops and environment informations. The movable sensing unit moves widely in a green house and gathers lots of information. The server saves these informations and provides them to customers with the direct commercing web page. This system will help farmers to control house environment and sales their crops in online market. Eventually It will be helpful for farmers to increase their benefits.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.3
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• pp.33-38
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• 2002

To establish the national standard of capacitance, four main electrodes of the cross capacitor which were evaluated to linearity and roundness less the $\pm 1 \mu m$ respectively have to be adjusted symmetrically in an inner cylinder. Four LM shafts with diameter of 5 mm were installed between main electrodes of the cross capacitor, and the electrodes were adjusted, as the first step, by means of the measured capacitance. In the second step, the symmetrical adjustment up to $\pm 1.2\mu m$ was performed by using a ball sensor, ball-type movable sensor, non-contacting capacitive sensor and upper guard sensor which were developed in this project.

• Transactions on Electrical and Electronic Materials
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• v.9 no.3
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• pp.128-133
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• 2008

In this paper, in order to analyze property of frequency response in microphone using optical sensor, acousto-optic sensor system has been implemented. The capacitance microphone and fiber-optic transmission path type fiber-optic microphone (FOM) have weaknesses in directivity, size, weight, and price. However suggested optical microphone can be constituted by cheap devices, so it has many benefits like small size, light weight, high directivity, etc. Head part of optical microphone which is suggested in this paper is movable back and forth by sound pressure with the attached reflection plate. Operating point has also been determined by measuring the response characteristics. The choosing the point, which has maximum linearity and sensitivity has changing the distance between optical head and vibrating plate. We measured the output of the O/E transformed signal of the optical microphone while frequency of sound signal is changed using sound measurement /analysis program, "Smaart Live" and "USBPre", which are based on PC, and compared the result from an existing capacitance microphone. The measured optical microphone showed almost similar output characteristics as those of the compared condenser microphone, and its bandwidth performance was about 4 kHz at up to 3 dB.