• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권11호
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• pp.2901-2919
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• 2012

Recent research in MEMS (Micro-Electro-Mechanical Systems) and wireless communication has enabled tracking of continuous objects, including fires, nuclear explosions and bio-chemical material diffusions. This paper proposes an energy-efficient scheme that detects and tracks different dynamic shapes of a continuous object (i.e., the inner and outer boundaries of a continuous object). EBCO (Efficient Boundary detection and tracking of Continuous Objects in WSNs) exploits the sensing capabilities of sensor nodes by automatically adjusting the sensing range to be either a boundary sensor node or not, instead of communicating to its neighboring sensor nodes because radio communication consumes more energy than adjusting the sensing range. The proposed scheme not only increases the tracking accuracy by choosing the bordering boundary sensor nodes on the phenomenon edge, but it also minimizes the power consumption by having little communication among sensor nodes. The simulation result shows that our proposed scheme minimizes the energy consumption and achieves more precise tracking results than existing approaches.

• 한국위성정보통신학회논문지
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• 제9권1호
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• pp.85-89
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• 2014

심전도(electrocardiography, ECG)는 심장박동을 할 때, 발생하는 탈분극과 재분극으로 심장의 전위변화를 시간의 흐름에 따라 파형으로 표현한 것이다. 의료기관에서는 심전도신호를 이용하여 환자의 심장질환을 진단한다. 일반적으로 사람의 정상적인 심장박동수는 1분에 60-100회 이다. 만약 정상적인 심장박동 수보다 느리거나 빠르다면 부정맥이라고 한다. 본 논문에서는 심전도신호에서 R-peak를 검출하여, R-R 간격을 구하고 부정맥 중에 서맥(bradycardia)과 빈맥(tachycardia) 구간을 검출하는 알고리즘을 제안하고 모의실험을 하였다.

• 한국ITS학회 논문지
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• 제10권3호
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• pp.79-84
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• 2011

본 논문에서는 ITS 응용을 위한 Alamouti 기법을 이용한 효과적인 차량 검출 성능을 분석하였다. 차량 검출은 DSRC (Dedicated Short Range Communication) 기반의 하이패스 환경에서 실험하였다. 시스템 성능으로는 비트 에러 확률로 실험 결과 값에 대하여 분석하였으며, 실험환경은 진입차량의 속도를 60km/h로 가정하여 DSRC 기반의 변조방식인 ASK 기법 을 적용하여 실험하였다. 또한 적용된 채널은 Rician 채널을 적용하여 LOS (Line of Sight)환경을 고려하며 실험을 하였다. 또한 사용된 반송파 주파수는 일본 DSRC 시스템 하향링크를 참고하여 5.8GHz를 적용하였다. 실험결과로 안테나가 2개일 경우와 Alamouti 기법을 적용할 때의 검출성능을 각각 나타내었으며, Alamouti 기법을 적용할 때 성능이 보다 개선되었음을 본 실험을 통해 알 수 있었다.

• Current Optics and Photonics
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• 제1권3호
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• pp.247-251
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• 2017

In this study, an ultraviolet Raman spectrometer was designed and fabricated to detect chemical contamination on the ground. The region of the Raman spectrum that indicated the characteristics of the chemicals was $350-3800cm^{-1}$. To fabricate a Raman spectrometer operating in this range, the layout and angle of optical components of the spectrometer were designed using a grating equation. Experimental devices were configured to measure the Raman spectra of chemicals based on the fabricated Raman spectrometer. The wavenumber of the spectrometer was calibrated by measuring the Raman spectrum of polytetrafluoroethylene, $O_2$, and $N_2$. The spectral range of the spectrometer was measured to be 23.46 nm ($3442cm^{-1}$) with a resolution of 0.195 nm ($30.3cm^{-1}$) at 253.65 nm. After calibration, the main Raman peaks of cyclohexane, methanol, and acetonitrile were found to be similar to the references within a relative error of 0.55%.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2003년도 종합학술발표회 논문집 Vol.13 No.1
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• pp.203-207
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• 2003

Due to the inherent nature of the low flying UAV, obstacle detection is a fundamental requirement in the flight path to avoid the collision from obstacles as well as manned aircraft. In this paper, a preliminary sensor requirements of an obstacle detection system for UAV in low-altitude flight are analyzed, and the automated obstacle detection sensor system is proposed assessing both passive and active sensors such as EO camera, IR, Laser radar, microwave and millimeter radar. In addition, TCAS (Traffic Alert and Collision Avoidance System) are reviewed for the collision avoidance of the manned aircraft system. It is suggested that small-sized radar sensor is the best candidate for the smart UAV because an active radar can provide the real-time informations on range and range rate in the all-weather environment. However, an important constraints on small UAV should be resolved in terms of accommodation of the mass, volume, and power allocated in the payload of the UAV system design requirements.

• 한국전자파학회논문지
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• 제25권1호
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• pp.123-129
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• 2014

고도 탐지 정확도는 장거리 다기능 레이더 등에서 필수적으로 분석되어야 하는 성능이지만, 기상 등 대기 현상에 의한 영향이 크기 때문에 정확한 분석이 어렵다. 따라서 고도에 따른 굴절율을 사용하여 보상을 수행하는데, 본 논문에서는 고층 기상에 의한 대기 굴절율을 고려할 수 있는 광선 추적 모의환경을 구축하고, 실환경 굴절율과 모델링된 굴절율을 각각 고려하여, 모델링된 굴절율을 실환경에 적용시 발생할 수 있는 고도 오차를 분석하였다. 모델링된 굴절율을 이용하여 고도 오차 보상값을 산출하였으며, 보상에 의한 결과를 모델링하여 고도 보상시 발생할 수 있는 고도 정확도를 정규함수로 모델링하여 통계적으로 분석하였다.

• 약학회지
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• 제41권1호
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• pp.74-80
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• 1997

A polygonal antibody against recombinant hirudin was raised for the development of a ELISA in biological fluids. Recombinant hirudin was conjugated to maleimide activated carrie r protein, KLH and injected to a rabbit. The third booster collection of antiserum was used as primary antibody for the ELISA. The titer for the detection antibody was determined. The direct ELISA could determine the concentration of hirudin in the range of ~10ng/ml. Affinity pulified IgG was obtained and conjugated to horseradish peroxidase. Purified IgG and IgG-HRP could be used as capture and detection antibody, respectively. Although sandwich ELISA would not give the satisfactory results. it could apply for the detection of hirudin level in the range of ~20 ${\mu}$g/ml.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3357-3361
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• 2013

Alumina microfibers with porous structures were prepared through hydrothermal reaction, and then used to modify the surface of carbon paste electrode (CPE). After modification with alumina microfibers, the electrochemical activity of CPE was found to be greatly improved. On the surface of alumina microfibers-modified CPE, the oxidation peak current of salvianolic acid B, a main bioactive compound in Danshen with anti-oxidative and anti-inflammatory effects, was remarkably increased compared with that on the bare CPE surface. The influences of pH value, amount of alumina microfibers and accumulation time were studied. Based on the strong signal amplification effects of alumina microfibers, a novel electrochemical method was developed for the detection of salvianolic acid B. The linear range was from 5 ${\mu}gL^{-1}$ to 0.3 mg $L^{-1}$, and the detection limit was 2 ${\mu}gL^{-1}$ (2.78 nM) after 1-min accumulation. The new method was successfully used to detect salvianolic acid B in ShuangDan oral liquid samples, and the recovery was over the range from 97.4% to 102.9%.

• 제어로봇시스템학회논문지
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• 제14권3호
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• pp.236-241
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• 2008

This paper presents a method to recognize the plane regions for movement of walking robots. When the autonomous agencies using stereo camera or laser scanning sensor is under unknown 3D environment, the mobile agency has to detect the plane regions to decide the moving direction and perform the given tasks. In this paper, we propose a very fast method for plane detection using normal vector of a triangle by 3 vertices defined on a small circular region. To reduce the effect of noises and outliers, the triangle rotates with respect to the center position of the circular region and generates a series of triangles with different normal vectors based on different three points on the boundary of the circular region. The vectors for several triangles are normalized and then median direction of the normal vectors is used to test the planarity of the circular region. The method is very fast and we prove the performance of algorithm for real range data obtained from a stereo camera system.

• 한국음향학회지
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• 제35권2호
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• pp.158-165
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• 2016

능동 소나 분야에서 잔향 환경에 강인한 펄스 형태에 대한 연구가 많이 진행되고 있다. 본 연구에서는 잔향환경에 강인하다고 알려진 PTFM(Pulse Trains of Frequency Modulated waveform), Costas, Geometric Comb 신호에 대해 이론적 특성 분석과 해상에서 실험한 데이터를 바탕으로 각 펄스별 ambiguity function 특성 및 분해능 특성을 비교/분석하였다. 분석 결과 PTFM 펄스는 부펄스에 의한 부엽에 의해 거리 분해능이 매우 낮아졌으며 Costas 펄스는 도플러 부엽에 의해 도플러 탐지 성능이 매우 떨어졌다. Geometric Comb 펄스는 CW(Continous Waveform)와 비슷한 분해능 특성을 보였으며 도플러 분해능이 가장 우수함을 확인하였다.