• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.283-286
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• 2002

In fiber optic sensor, the error of the measurement is influenced by the surface roughness of the target and surroundings, especially the outside light. To reduce or modify this error, the sensitivity of the fiber optic sensor and the noise change by the surface roughness of the target should be known. The purpose of this paper is to observe the sensitivity of the fiber optic sensor and the noise according to the surface roughness of the target.

• IMMUNE NETWORK
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• 제1권2호
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• pp.162-169
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• 2001

Background: Nitric oxide (NO), a cytotoxic molecule is produced in various tissues including tumor cells during interleukin-2 (IL-2) therapy . Lymphokine-activated killer (LAK) cells are induced during IL-2 therapy, and have cytotoxic activity against tumor cells. The current study investigated the effects of NO synthesized in target cells or exposure of target cells to NO on the sensitivity of target cells to LAK cell cytotoxicity. Methods: Cytotoxicity was measured using 4 h chromium release assays. LAK cells which were induced by a 4 day incubation of BALB/c mouse splenocytes with IL-2 (6,000 IU/mL) were employed as effector cells. RD-995 skin tumor cells originated from a C3H/HeN mouse were employed as target cells. NO synthesis in target cells was induced by a 24 h incubation of RD-995 cells with $IFN{\gamma}$ (25 U/mL), TNF (50 U/mL) and IL-1 (20 U/mL). S-nitrosyl acetylpenicillamine (SNAP), an NO donor, was used to expose target cells to NO. $N^G$-monomethyl-L-arginine (MLA) and carboxy-PTIO were added during cytotoxicity assays to inhibit NO synthesis, and to scavenge NO produced by target cells, respectively. Results: Sensitivity of NO-producing RD-995 cells to LAK cell cytotoxicity was decreased by addition of MLA and carboxy-PTIO during cytotoxicity assays. However, the two reagents had no effect on the sensitivity of non-NO-producing RD-995 cells. Pretreatment of RD-995 target cells with SNAP increased the sensitivity in comparison with untreated cells. Conclusions: Sensitivity of target cells to LAK cell cytotoxicity is increased by target cell NO synthesis or exposure to NO. Further studies are needed to evaluate whether these in vitro results have relevance to in vivo phenomena.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.402-405
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• 2006

Radiometric calibration of optical image data is necessary to convert raw digital number (DN) value of each pixel into a physically meaningful measurement (radiance). To extract rather quantitative information regarding biophysical characteristics of the earth surface materials, radiometric calibration is often essential procedure. A sensor detects the radiation of sunlight interacted atmospheric constituents. Therefore, the amount of the energy reaching at the sensor is quite different from the initial amount reflected from the surface. To achieve the target reflectance after atmospheric correct, an initial step is to convert DN value to at-sensor radiance. A linear model, the simplest radiometric model, is applied to averaged spectral radiance for this conversion. This study purposes to analyze the sensitivity of several factors affecting on radiance for carrying out absolute radiometric calibration of panchromatic images from KOMPSAT2 launched at July, 2006. MODTRAN is used to calculate radiance at sensor and reflectance of target is measured by a portable spectro-radiometer at the same time the satellite is passing the target for the radiometric calibration. As using different contents of materials composing of atmosphere, the differences of radiance are investigated. Because the spectral sensitivity of panchromatic images of KOMPSAT2 ranges from 500 to 900 nm, the materials causing scattering in visible range are mainly considered to analyze the sensitivity. According to the verified sensitivity, direct measurement can be recommenced for absolute radiometric calibration.

• Current Optics and Photonics
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• 제3권6호
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• pp.566-570
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• 2019

To investigate dependence of the sensitivity of THz metamaterials on the position of target dielectric materials, we functionalized the metamaterial gap with an adhesive polymer. A shift in resonance frequency occurs when polystyrene microbeads are deposited in the gap of the metamaterial's metal resonator pattern, while little change is observed when they are deposited on other areas of the metasurface. A two-dimensional mapping of the sensitivity, with a grid size of 1 ㎛, is obtained from a finite-difference time-domain simulation: The frequency shift is displayed as a function of the position of a target dielectric cube. The resulting sensitivity distribution clearly reveals the crucial role of the gap in sensing with metamaterials, which is consistent with the electric field distribution near the gap.

• 한국인터넷방송통신학회논문지
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• 제13권3호
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• pp.165-170
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• 2013

공간상에서 원하는 목표물의 도래 방향 추정은 수신 안테나에 입사하는 신호의 입사 방향을 찾는 것이다. 본 논문에서는 최대 우도 추정 방법을 이용하여 원하는 목표물의 도래 방향을 추정하였다. 도래 방향 추정방법은 최대 우도 방법에서 수신 신호 한계점 이상의 신호에 특이 값 분해를 적용하여 최대 우도 추정의 첨예도를 계산하여 원하는 목표물을 추정하였다. 모의실험을 통하여 본 연구에서 제안된 방법의 성능을 기존 방법과 비교분석하였다. 목표물 도래방향 추정에서 본 연구에서 제안한 방법이 고유치 전개를 하지 않기 때문에 처리시간 단축에서 효과적이고 원하는 목표물의 방향을 정확히 추정하였다. 본 연구에서 제안한 방법이 목표물 추정에서 기존 방법보다 우수함을 나타내었다.

• Journal of electromagnetic engineering and science
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• 제11권1호
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• pp.1-4
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• 2011

In this letter, we propose a novel tag antenna that has low performance degradation with nearby dielectric material. We obtained a stable reading performance and a broad matching bandwidth on nearby dielectric materials by employing a T-matching network with thick line width and capacitively slot-loaded arms. We then built the proposed antenna and measured the tag sensitivity to examine the reading characteristics with nearby dielectric materials. The measured results clearly demonstrate stable tag sensitivity with various nearby dielectric materials, such as foam, acrylic-plastic, glass, and ceramic plates. To more closely observe the antenna characteristics with nearby dielectric materials, we also examined the impedance variation and surface current distribution with respect to the dielectric constant of nearby target objects, which ranged from $1{\times}{\varepsilon}_0$ to $16{\times}{\varepsilon}_0$.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.769-772
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• 2013

When developing engine mount, interm mount bracket 1st resonance is critical to make sound quality better or worse. So, at the initial stage of development, we need to consider some design parameter to setup the target of interm bracket 1st resonance. Especially, 3cylinder interm bracket guideline is not well known. So, this paper deals with some important sensitivity which should be considered during the development of vehicle. From source to interior side, we should know the component sensitivity like body sensitivity p/F or bracket gain etc. Through this paper, we could get the knowledge of design guideline and key consideration points.

• Nuclear Engineering and Technology
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• 제50권1호
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• pp.182-189
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• 2018

A neutron generation system was developed to induce fissile fission in a lead slowing down spectrometer (LSDS) system. The source neutron is one of the key factors for LSDS system work. The LSDS was developed to quantify the isotopic contents of fissile materials in spent nuclear fuel and recycled fuel. The source neutron is produced at a multilayered target by the (e,${\gamma}$)(${\gamma}$,n) reaction and slowed down at the lead medium. Activation analysis of the target materials is necessary to estimate the lifetime, durability, and safety of the target system. The CINDER90 code was used for the activation analysis, and it can involve three-dimensional geometry, position dependent neutron flux, and multigroup cross-section libraries. Several sensitivity calculations for a metal target with different geometries, materials, and coolants were done to achieve a high neutron generation rate and a low activation characteristic. Based on the results of the activation analysis, tantalum was chosen as a target material due to its better activation characteristics, and helium gas was suggested as a coolant. In addition, activation in a lead medium was performed. After a distance of 55 cm from the lead surface to the neutron incidence, the neutron intensity dramatically decreased; this result indicates very low activation.

• 한국음향학회지
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• 제26권1호
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• pp.42-47
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• 2007

본 논문에서는 probe DNA의 고정화 및 Probe DNA와 target DNA의 혼성화 반응을 감지할 수 있는 DNA 측정용 고주파 SAW 센서의 주파수 증대에 따른 감도향상에 대해 연구하였다. 센서는 $36^{\circ}$ YX $LiTaO_3$ 압전 단결정 기판위에 Au 박막이 증착된 측정채널 (sensing channel)과 기준채널 (reference channel)로 구성되며 200MHz에서 발진되는 이중 지연선 형태로 제작되었다. 또한 SAW 센서의 감지 미케니즘의 최적화를 위해 SAW 센서의 Au 지연선상의 Probe DNA의 최적 고정화 반응농도와 target DNA의 최적 혼성화 반응농도를 결정하였으며, 디지털 시린지 펌프시스템을 구성하여 실험자에 따른 오차를 최소화하였다. 측정채널의 Au 박막 지연선상에 probe DNA를 고정화시킨 후 target DNA를 주입하면, DNA의 혼성화 반응이 일어나며 Au 지연선상의 질량이 변하게 된다. 따라서 질량하중 효과에 대한 센서의 주파수 변화를 측정하였다. 개발된 센서는 최대 0.066ng/ml/Hz의 민감도를 가지며 질량하중 효과에 대한 안정적인 주파수 변화를 나타내었다.

• 대한지구과학교육학회지
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• 제6권2호
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• pp.145-151
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• 2013

The aim of this research is clarify the relationship between concept understanding degree about the environment and environmental sensitivity and heighten understanding of environmental education target to pre-service elementary teacher. The subjects of this study are science education intensive course 65 students of B educational university. Concept understanding degree about the environment was separately investigated by 'the definition of environmental education', 'Write The positive concept of the natural environment education and briefly describe.''The negative concept of the natural environment education and briefly describe'. Next clarify the relationship between concept understanding degree about the environment and environmental sensitivity target to pre-service elementary teacher. Based on these results, propose an alternative to cultivate pre-service elementary teacher's knowledge about environmental education. Degree of understanding of the concept environmental education research results are as follows. First, Cognition degree about definition of environmental education of pre-service elementary teacher is correctly recognized generally. Second, They do not think deeply about natural environment when it comes to the positive concept of the natural environment of pre-service elementary teacher. Third, They have only a little interest in natural environment when it comes to the negative concept of the natural environment of pre-service elementary teacher. Correlation research results of degree of understanding of the concept of environmental and environmental sensitivity are as follows. High understanding degree of environmental education is high environmental sensitivity. Heighten environmental sensitivity of pre-service elementary teacher will be sustainable environmental education so education is necessary for environmental Sensitivity training.