• 인터넷정보학회논문지
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• 제12권2호
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• pp.47-53
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• 2011

무선센서네트워크에서 살포한 센서 중 일부의 결함이 발생하거나 에너지가 고갈될 시, 이동 센서(Mobile Sensor)들의 재배치로 결함이 발생한 지역(즉, 센싱 홀: Sensing Hole)을 복구할 수 있다. 수많은 바위 등이 즐비한 거친 지역에서는 바퀴 기반의 이동센서는 적당하지 않으므로 점프를 통해 이동이 가능한 홉핑 센서가 필요하다. 본 논문에서는 발생한 센싱 홀의 복구를 위한 재배치 문제 및 그에 따른 다양한 문제들을 살펴본다. 과거 홉핑 센서들을 이동시키기 위하여 단지 최단경로만을 고려하였으나, 본 논문에서는 최대 엇갈림 없는 경로 및 다중경로를 활용하여 또다른 센싱홀의 발생을 막을 수 있었다. 시뮬레이션 결과는 제안하는 기법들이 최단경로를 기반으로 한 기법에 비해 홉핑 센서의 균형적인 분배와 이동성공률에서 우수함을 보인다.

• Structural Engineering and Mechanics
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• 제25권5호
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• pp.577-596
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• 2007

Recent development of fiber optic sensor technology has provided an excellent choice for civil engineers for performance monitoring of civil infrastructures. Fiber optic sensors have the advantages of small dimensions, good resolution and accuracy, as well as excellent ability to transmit signal at long distances. They are also immune to electromagnetic and radio frequency interference and may incorporate a series of interrogated sensors multiplexed along a single fiber. These advantages make fiber optic sensors a better method than traditional damage detection methods and devices to some extent. This paper provides a review of recent developments in fiber optic sensor technology as well as some applications of fiber optic sensors to the performance monitoring of civil infrastructures such as buildings, bridges, pavements, dams, pipelines, tunnels, piles, etc. Existing problems of fiber optic sensors with their applications to civil structural performance monitoring are also discussed.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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• pp.440-447
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• 2005

In this study, strain measurement and its applicability to estimated deflection curve using fiber bragg grating sensors was conducted. For this purpose, reinforced concrete beams were made and sensors were attached both on the surface of the beams and inside steel. Two types of sensors were used to detect strain on the beams and steel : fiber bragg grating sensors, electric resistance strain sensors. So fatigue test is done with measuring strain of specimen. In addition, this experiments estimates the optimum deflection curve that converts strain curve data measured by FBG sensors into deflection.

• 전기학회논문지
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• 제58권7호
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• pp.1398-1404
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• 2009

This paper proposes a vehicle speed detector with anisotropic magnetoresistive (AMR) sensors and addresses experimental results to show the performance of the detector. The detector consists of two AMR sensors and mechanical and electronic apparatuses. The AMR sensor senses disturbance of the earth magnetic field caused by a vehicle moving over the sensor and then produces an output indicative of the moving vehicle. In this paper, vehicle speeds are calculated by using two AMR sensors built on a board. The speed of a vehicle is calculated by dividing the known distance between the two sensors with the time difference between two output signals from each sensor, captured sequentially while the vehicle is driving over the sensors. Some field tests have been carried to show the performance of the proposed detector and its usefulness.

• 센서학회지
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• 제25권2호
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• pp.103-109
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• 2016

Recent light-enhanced metal oxide gas sensors are reviewed in this article. The basic mechanisms of a light-enhanced metal oxide gas sensor are discussed. Many literatures reveal that the standalone sensitivity and the response/recovery time enhancements enabled by the exposing light are not as high as the performance enhancement provided by external heating. Therefore, both optimal amount of external heating and exposed light intensity are necessary to increase the performance of these light-enhanced gas sensors. The development of highly light sensitive materials and structures is important to lower the overall power consumptions of the sensors.

• 센서학회지
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• 제29권1호
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• pp.1-6
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• 2020

Gas sensors that operate at room temperature have been extensively studied because of sensor stability, lift time, and power consumption. To design effective room-temperature gas sensors, various nanostructures, such as nanoparticles, nanotubes, nanodomes, or nanofibers, are utilized because of their large-surface-to-volume ratio and unique surface properties. In addition, two-dimensional materials, including MoS₂, SnS₂, WS₂, and MoSe, and ultraviolet-activated methods have been studied to develop ideal room-temperature gas sensors. Herein, a brief overview of state-of-the-art research on room-temperature gas sensors and their sensing properties, including nanostructured materials, two-dimensional materials, the ultraviolet-activated method, and ionic-activated gas sensors, is provided.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.160-163
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• 2005

Several sensors are involved in the cor개sion monitoring of concrete structures. This paper deals with the monitoring of concrete structures by embeddable reference sensors. $MnO_2$, MMO and graphite reference sensors are fabricated in the laboratory as suitable as embeddable type into the concrete structures. Sensors are embedded into the mortars and the performance was studied in the absence and presence of chloride ions. The electrochemical stability of the sensors was carried out for the exposure period of one year. Polarisation behaviour and impedance of the sensors in mortar was carried out in three aqueous solutions namely distilled water, 3% NaCl and natural sea water.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.124-127
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• 2000

In this study, a technique for monitoring of fatigue damage of composite laminates by measuring the stiffness change using embedded intensity-based optical fiber sensors was investigated. Firstly, the underlying measurement principle and structure of intensity-based sensors and then a simple stiffness conversion process was explained. The monitoring technique was evaluated by fatigue tests of composite laminates with an embedded intensity-based sensor. From the test results, the response of the intensity-based sensor showed good correlation with that of surface mounted extensometer. Therefore, it can be concluded that the intensity-based sensors have good potential for the monitoring of fatigue damage of composite structures under fatigue loading. In addition, it could be confirmed that the intensity-based sensors have higher resistance to fatigue than the commercial electrical strain gauge.

• 정보와 통신
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• 제30권10호
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• pp.79-85
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• 2013

By interacting with external wireless sensors, smartphones can gather high-fidelity data on the surrounding environment to develop various environment-aware, personalized applications. In this work we introduce the sensor virtualization module (SVM), which virtualizes external sensors so that smartphone applications can easily utilize a large number of external sensing resources. Implemented on the Android platform, our SVM simplifies the management of external sensors by abstracting them as virtual sensors to provide the capability of resolving conflicting data requests from multiple applications and also allowing sensor data fusion for data from different sensors to create new customized sensors elements. We envision our SVM to open the possibilities of designing novel personalized smartphone applications.

• 한국표면공학회지
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• 제29권5호
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• pp.459-466
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• 1996

A great amount of effort has been devoted to the constant improvement of such basic performance as dirvability, safety and enviromental protection. As a result, the total combination of various technologies has made it possible to produce safer and more comfortable automobiles. Among these technologies, plasma and thin film techniques are mainly cocerned with sensors, optics, electronics and surface modification. This paper first describes a concept of thin film processing in materials synthesis for sensors based on particle-surface interaction during deposition to provide a long life sensor applicable to sutomobiles. Some examples of parctical application of thin films to sensors are then given. These include(1) a thin films strain gauge for gravity sensors, (2) a giant magneto resistance film for speen sensors, and (3) a Magneto-impedance sensors fordetection of low magnetic field. Further progress of sophisticated thin film technology must be considered in detail to explore advanced thin film materials science and to ensure the field reliability of future sensor devices for automobile.