• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.87-87
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• 2013

The interface between nanomaterials and biosystems is emerging as one of the broadest and most dynamic areas of science and technology, bringing together biology, chemistry, physics and many areas of engineering, biomedicine. The combination of these diverse areas of research promised to yield revolutionary advances in healthcare, medicine, and life science. For example, the creation of new and powerful nanosensors that enable direct, sensitive, and rapid analysis of biological and chemical species can advance the diagnosis and treatment of disease, discovery and screening of new drug molecules. Nanowire based sensors are emerging as a powerful and general platform for ultrasensitive and multiplex detection of biological and chemical species. Here, we present the studies about noble metal nanowire sensors that can be used for sensitive detection of a wide-range of biological and chemical species including nucleic acids, proteins, and toxic metal ions. Moreover, the optical and electrochemical applications of noble metal nanowires are introduced. Noble metal nanowires are successfully used as plasmonic antennas and nanoelectrodes, thereby provide a pathway for a single molecule sensor, in vivo neural recording, and molecular injection and detection in a single living cell.

• 한국인터넷방송통신학회논문지
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• 제16권4호
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• pp.133-137
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• 2016

IoT정보중 영상과 음성 정보가 많은 부분을 차지한다. 더 정확한 상황 인식과 주 정보의 부재에서 사용할 수 있는 다양한 센서가 요구되고 있다. 다양한 센서 사용에 따른 자원 관리의 증가로 이어진다. 여러 센서의 정보 전달에서 소요되는 자원을 줄이는 방법으로서 센서정보를 가공하여 다른 센서를 대신할 수 있는 가능성을 찾아본다. 본 논문에서는 LIS302 DL MEMS 모션센서를 사용하여 탁구대로 낙하하는 탁구공, 셔틀콕, 테니스공의 데이터를 측정하였다. 3가지 대상체에서 측정한 데이터는 충격량에 비례하는 함을 확인하였다. 이 실험은 가속도 센서를 사용하여 충격량으로 변경될 수 있음을 확인하였다. 이 결과 단일 센서를 사용하여 다기능구현이 가능함을 보였다. 또한, 센서의 초기 개발단계에서 다기능센서 고려 상황을 인식하게 한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1268-1271
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• 2005

This paper proposes a compact-sized surface myoelectric sensor for myoelectric hand prosthesis. To fit the surface myoelectric sensor in the socket of the myoelectric hand prosthesis, the sensor should be a compact size. The surface myoelectric sensor is composed of a skin interface and a single processing circuit that are mounted on a single package. Since the skin interface has one reference and two input electrodes, and the reference electrode is located in middle of two input electrodes, we propose two types of sensors with the circle- and bar-shaped reference electrode, but all input electrodes are the bar-shaped. The metal material used for the electrodes is the stainless steel (SUS440) that endures sweat and wet conditions. Considering conduction velocity and median frequency of the myoelectric signal, we select the inter-electrode distance (IED) between two input electrodes as 18mm, 20mm, and 22 mm. The signal processing circuit consists of a differential amplifier with band pass filter, a band rejection filter for rejecting 60Hz power-line noise, amplifiers, and a mean absolute value circuit. We evaluate the proposed sensor from the output characteristics according to the IED and the shape of the reference electrode. From the experimental results we show the surface myoelectric sensor with the 18mm IED and the bar-shaped reference electrode is suitable for the myoelectric hand prosthesis.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2004년도 춘계학술발표대회 논문집
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• pp.135-138
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• 2004

Conventional piezoelectric lead-zirconate-titanate (PZT) senor has high sensitivity, but it is very brittle. Recently polymer films such as polyvinylidene fluoride (PVDF) and poly(vinylidene fluoride­trifluoroethylene) (P(VDF-TrFE)) copolymer have been used as a sensor. The advantages of polymer sensor are the flexibility and mechanical toughness. Simple process and possible several shapes are also additional advantages. Polymer sensor can be directly embedded in a structure. In this study, nondestructive damage sensitivity of single basalt fiber/epoxy composites was investigated with sensor type and thermal damage using AE and oscilloscope. And AE waveform for epoxy matrix with various damage types was compared to each other. The damage sensitivity of two polymer sensors was rather lower than that of PZT sensor. The damage sensitivity of PVDF sensor did not decrease until thermal damage temperature at $80^{\circ}C$ and they decreased significantly at $110^{\circ}C$ However, the damage sensitivity of P(VDF-TrFE) sensor at $110^{\circ}C$ was almost same in no damage sensor. For both top and side impacts, the difference in arrival time increased with increasing internal and surface damage density of epoxy matrix.

• 한국정보통신학회논문지
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• 제23권7호
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• pp.771-778
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• 2019

기존 단일 조도센서를 이용한 조도검출 방식은 좁은 FOV (Field of View) 특성 상 측정 위치에 따라 검출 조도의 균일도가 저하된다. 다수개의 조도센서를 통해 평균 조도값을 검출하는 방법은 복잡도 증가 및 계산과정에서 오류가 증가하는 문제점을 가지고 있다. 본 논문에서는 넓은 FOV를 가지는 하나의 이미지센서를 기반으로 한 조도검출 방법을 제안하였으며, 제안된 방법은 기존 조도센서가 가지는 시스템 복잡도, 오류 증가 등의 문제점이 해결 가능하다. 실내 환경에서의 성능평가 결과는 색차조도계 (CL-200A)를 이용한 기준값 대비 조도센서가 1개인 경우 평균 12%, 조도센서가 5개인 경우 평균 10.7%, 이미지센서의 경우 평균 6.2% 차이가 발생하는 것을 확인하였으며, 이를 통해 이미지센서를 기반으로 한 제안된 검출방법은 균일성이 향상된 공간조도를 간단하고 정확하게 검출할 수 있음을 확인하였다.

• 대한의용생체공학회:의공학회지
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• 제36권5호
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• pp.143-149
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• 2015

In this paper, we proposed a novel method for automatic detection for snoring and heart beat using a single piezoelectric sensor. For this study multi-rate signal processing technique was applied to detect snoring and heart beat from the single source signal. The sound event duration and intensity features were used to snore detection and heart beat was found by autocorrelation. The performance of the proposed method was evaluated on clinical database, which is the nocturnal piezoelectric snoring data of 30 patients that suffered obstructive sleep apnea. The method achieved sensitivity of 88.6%, specificity of 96.1% with accuracy of 95.6% for snoring and sensitivity of 94.1% and positive predictive value of 87.6% for heart beat, respectively. These results suggest that the proposed method can be a useful tool in sleep monitoring and sleep disordered breathing diagnosis.

• Journal of Power Electronics
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• 제12권6호
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• pp.895-903
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• 2012

This paper presents a fast switching direct torque control (FS-DTC) using only a single DC-link current sensor. In FS-DTC, six new active voltage complex space vectors (CSVs) are synthesized by the conventional active voltage space vectors (SVs). The corresponding sectors are rotated in the anticlockwise direction by 30 degrees. A selection table is defined to select the CSVs. Based on the "Different Phase Mode", the output sequence of the selected CSV is optimized. Accordingly, a reconstruction method is proposed to acquire the phase currents. The core of the FS-DTC is that all of the three phase currents can be reliably reconstructed during every two sampling periods, which is the result of the fast switching between different phases. The errors between the reconstructed and actual currents are strictly limited in one sampling period. The FS-DTC has the advantages of the standard DTC scheme such as simple structure, quick torque response and robustness. As can be seen in the analysis, the FS-DTC can be thought of as an equivalent standard DTC scheme with 86.6% of the maximum speed, 173.2% of the torque ripple, and 115% of the response time of the torque. Based on a dSPACE DS1103 controller, the FS-DTC is implemented in an induction machine drive system. The results verify the effectiveness of the FS-DTC.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.189-192
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• 2009

이 논문은 디지털 카메라의 싱글 센서에 있는 CFA의 다양한 패턴을 비교, 분석하는데 목적을 두고 있다. 이미 널리 쓰이고 있는 패턴들이 있으나, 이미지들은 간혹 사람들이 실제로 보는 것보다 어둡게 나오거나 밝게 나오거나 또는 약간의 노이즈 현상, 불러 현상을 보여주기도 한다. 이를 개선하기 위해 아직도 많은 학자들이 패턴의 연구를 하고 있다. 이 연구는 Bayer패턴을 포함하여 7개의 패턴을 실험한다. 실험의 객관성을 위해 보간법은 선형방법으로 통일 하여 실험한다. 실험 결과는 패턴의 다양성이 이미지 향상에 크게 영향을 주지 않는다는 걸 보여주다. 그리고 패턴에 따라 그에 맞는 보간법이 필요하다는 것을 보여준다.

• 제어로봇시스템학회논문지
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• 제18권8호
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• pp.780-786
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• 2012

Surveillance has become one of promising application areas of wireless sensor networks which allow for pervasive monitoring of concerned environmental phenomena by facilitating context awareness through sensor fusion. Existing systems that depend on a postmortem context analysis of sensor data on a centralized server expose several shortcomings, including a single point of failure, wasteful energy consumption due to unnecessary data transfer as well as deficiency of scalability. As an opposite direction, this paper proposes an energy-efficient distributed context-aware surveillance in which sensor nodes in the wireless sensor network collaborate with neighbors in a distributed manner to analyze and aware surrounding context. We design and implement multi-modal sensor stations for use as sensor nodes in our wireless sensor network implementing our distributed context awareness. This paper presents an initial experimental performance result of our proposed system. Results show that multi-modal sensor performance of our sensor station, a key enabling factor for distributed context awareness, is comparable to each independent sensor setting. They also show that its initial performance of context-awareness is satisfactory for a set of introductory surveillance scenarios in the current interim stage of our ongoing research.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.169-172
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• 2002

A vision sensor measure range data using laser light source. This sensor generally use patterned laser which shaped single line. But this vision sensor cannot satisfy new trend which feeds foster and more precise processing. The sensor's sampling rate increases as reduced image processing time. However, the sampling rate can not over 30fps, because a camera has mechanical sampling limit. If we use multi line laser pattern, we will measure multi range data in one image. In the case of using same sampling rate camera, number of 2D range data profile in one second is directly proportional to laser line's number. For example, the vision sensor using 5 laser lines can sample 150 profiles per second in best condition.