• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2003년도 하계 학술대회 논문집
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• pp.484-489
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• 2003

In September 2001, BSE was found for the first time in Japan. From then, consumers have been more and more interested in the safety of food products. Therefore, breeders and participants have to make a tracing system of productive information of cows and guarantee the quality of products through that system in an emergency Then the government has decided to put ear tags with peculiar numbers on all the cows and control the information of individual production and transference. But the ear tag can be damaged and missing. There is also a research of identification by implanting a microchip into the cow's body. But there are problems that the research can give a distress on cows and the detectable distance is too short. (omitted)

• 천문학회보
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• 제41권1호
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• pp.31.3-31.3
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• 2016

Exploring a universe with gravitational waves (GWs) was only theoretical expectation for long time. In September 2015, the Laser Interferometer GW Observatory (LIGO) first detected GWs emitted from the collision of two stellar-mass black holes in cosmological distance (1.3 billion light years) on Earth. This confirms the existence of black-hole binary mergers, and further, opens a new field of GW astronomy. We begin our discussion with a list of important GW sources that can be detectable on Earth by large-scale laser interferometers such as LIGO. Focusing on compact objects such as neutron stars and black holes, we then discuss possible research in the context of GW astronomy. By coordinating with existing observatories, searching for electromagnetic waves or particles from astronomical objects, around the world, multi-messenger astronomy for the universe's most cataclysmic phenomena (e.g. gamma-ray bursts) will be available in the near future.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.7-7
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• 2000

A high $T_c$ SQUID system is developed for the application to biological immunoassay. In this application, magnetic nanoparticles are used as magnetic markers to perform immunoassay, i.e., to detect binding reaction between an antigen and its antibody. The antibody is labeled with ${\gamma}-Fe_2O_3\;(or\;Fe_3O_4)$ nanoparticles, and the binding reaction can be magnetically detected by measuring the magnetic field from the nanoparticles. Design and set up of the system is described. The system consists of (1) SQUID magnetometer or gradiometer made of 30-deg. bicrystal junctions, (2) field and compensation coils to apply the magnetic field of about 1 mT, (3) special Dewar to realize a 2 mm-distance between the SQUID and the sample, (4) two layers of cylindrical shielding to reduce the extemal magnetic noise to about 1/100, and (5) an electric slider to move the sample with a speed of 10 mm/sec. The sensitivity of the system is studied in terms of detectable magnetic flux. For the measurement bandwidth from 0.2 Hz to 10 Hz, minimum-detectable amplitude of the magnetic flux is $0.8\;m\;{\Phi}_o$ and $0.25\;m{\Phi}_o$ for the magnetometer and the gradiometer, respectively, when the magnetic field of 1 mT is applied. The difference between them is due to the residual environmental noise, and the applied magnetic field does not increase the system noise. The corresponding weight of the magnetic markers is 1 ng and 310 pg, respectively. An experiment is also conducted to measure antigen-antibody reaction with the present system. It is shown that the sensitivity of the present system is 10 times better than that of the conventional method using an optical marker. A one order of magnitude improvement of sensitivity will be realized by the sophistication of the present system.

• Journal of the Optical Society of Korea
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• 제16권4호
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• pp.331-335
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• 2012

A miniaturized laser beam transmitter, in which a visible laser module at ${\lambda}$=650 nm is precisely stacked upon an infrared (IR) module at ${\lambda}$=905 nm, has been proposed and constructed to provide an IR collimated beam in conjunction with a collinear monitoring visible beam. In particular, the IR beam is selectively dispersed through a perforated sheet diffuser, so as to create a rapidly diverging close-range beam in addition to a highly defined long-range beam simultaneously. The complementary close-range beam plays a role in mitigating the blind region in the vicinity of the transmitter, which is inevitably missed by the main long-range beam, thereby uniformly extending the transmitter's effective trajectory that is sensed by a receiver. The proposed transmitter was designed through numerical simulations and then fabricated by incorporating a diffuser sheet, perforated with an aperture of 2 mm. For the manufactured transmitter, the IR long-range beam was observed to have divergences of ~2.3 and 1.6 mrad in the fast and slow axes, respectively, while the short-range beam yielded a divergence of ~24 mrad. The angular alignment between the long-range IR and visible beams was as accurate as ~0.5 mrad. According to an outdoor feasibility test involving a receiver, the combination of the IR long- and short-range beams was proven to achieve a nearly uniform trajectory over a distance ranging up to ~600 m, with an average detectable cross-section of ${\sim}60{\times}80cm^2$.

• ALGAE
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• 제17권1호
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• pp.41-51
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• 2002

Three dominant rocky intertidal macroalgae, the fucoids Fucus gardneri and Pelvetiopsis limitata (Phaeophyta) and the red alga Mazzaella cornucopiae (= Iridaea cornucopiae) on the west coast of Vancouver Island, British Columbia, Canada were used in a series of field experiments to examine interspecific interactions. These experiments showed complex patterns which included an interchange of negative (inhibition) and positive (facilitation) interactions depending on neighbor distance. Less fucoid recruitment occurred in the plots with greater percent cover of a turfforming red alga, M. cornucopiae. However, experimentally removing Mazzaella turf (the turf was considered to be "blocking" fucoid recruits or "shading" growing recruits) did not increase recruitment. This result indicated that there may be another factor(s) involved in the survivorship of juvenile fucoids in the turf-removed plots. Morphological differences in adult plants between Mazzaella and the two fucoids resulted in another type of interaction; these began when fucoids successfully settled and grew nearby or within the red algal turf. By monitoring microhabitat at the individual plant level for two years, I found that survivorship of fucoid recruits showed different species-specific patterns. The patterns also varied as the microhabitat changed from Mazzaella turf edge to open space. For F. gardneri, longevity of P.limitata at all distances tested was similar. A reason for greater longevity of F. gardneri individuals at edge microhabitats may be that these sites have one side open to light and nutrients and another site that buffers them from desiccation and wave impact. In the Mazzaella-Fucus interaction, neighbor distance was a key factor in determining whether the outcome of the interaction would be competition or facilitation (or protection). This study provides experimental evidence that detectable biological interactions occur in this upper intertidal algal community where physical conditions are usually severe, and also indicates the importance of small scale examination in understanding macroalgal interactions in intertidal habitats.

• 한국결정성장학회지
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• 제32권5호
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• pp.205-211
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• 2022

GSV (Granule Spray in Vacuum)는 상온의 진공하에서 나노 크기의 치밀한 세라믹 코팅층을 형성하는 방법이다. 일반적으로, 단사정의 지르코니아는 1150℃에서 정방정으로 변태하며, 이때 6.5 %의 체적변화를 일으켜 치밀한 단사정의 지르코니아를 만들기 어렵다. 본 연구에서는 코팅 효율에 대한 두 가지 처리 변수의 효과를 조사하는 데 중점을 두었다. 아울러, 특별한 가열과정 없이 형성된 필름의 미세구조에 관찰하였다. 샘플 기판에 증착된 지르코니아 필름에 대한 X-ray diffractometer (XRD) 분석은 단사정 지르코니아 필름이 성공적으로 증착되었음을 보여주었다.

• 해양환경안전학회지
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• 제15권3호
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• pp.243-250
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• 2009

연안에서 목적으로 하는 어업에 적합하도록 소형 어군탐지기를 효율적으로 설계하고 평가할 수 있는 방법에 대해 검토하기 위하여 일반적으로 사용되고 있는 어군탐지기의 특성과 탐지범위 등에 대해 조사하였다. 먼저 일반적인 어군탐지기의 빔폭은 주파수와 송신전력이 상승함에 따라 좁아지고 송수파기의 직경은 송신전력이 증가함에 커지는 경향을 보였다. 이 특성을 이용하여 상업적으로 사용되는 일반적인 어군탐지기의 신호대 잡음비를 유도하였다. 탐지거리와 탐지폭으로 구성되는 탐지범위는 이 신호대 잡음비(SN비)로부터 얻을 수 있다. 탐지거리는 주파수의 증가와 함께 증가하였지만 고주파에서는 흡수계수의 영향으로 원거리 탐지가 어려워진다. 즉 송수파기 직경, 송신전력의 증가에 따른 효과는 저주파에서는 크고, 고주파에서는 적은 경향을 보인다. 탐지범위 등을 종합적으로 응용하여 휴대용 어군탐지기의 설계 범용도를 작성하였다. 범용도에는 SN비를 송수파기의 직경, 빔폭, 탐지거리를 변수로하여 주파수에 대해 표시하였다. 범용도에서 SN비가 높고 실용성이 높은 적절한 설계영역을 표시하였다. 설계영역에서 설계점을 정하면 전체적으로 적절한 설계를 할 수 있다. 설계범용도는 어군탐지기의 성능평가에도 응용할 수 있다.

• 수산해양기술연구
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• 제27권1호
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• pp.31-40
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• 1991

원격측정에 의한 어군의 탐지범위를 넓히기 위하여 기존 net recorder를 4개의 진동자로 사용할 수 있는 멀티비임 시스템으로 바꾸어, 이들을 직선배열과 평면배열하여 어군탐지범위의 확대폭과 어군의 위치측정에 대한 원격제어 실험을 행하고 그 유용성을 검토.분석한 결과는 다음과 같다. 1. 직선배열에 의한 표적의 탐지범위는 수심과 진동자 간격의 증가함에 따라 증가하였으며, 4개의 진동자를 배열하면 4배까지 확대할 수 있었다. 2. 진동자를 직선배열하여 정치망입구에서 어군을 관측한 결과 길그물에 아주 가까운 2.5~3.5m의 수층으로 많이 입망되었으며, 창그물에 가까운 3.5~4.5m의 수층으로도 어느 정도 입망되었다. 3. 표적의 실제위치와 진동자의 평면배열에 의하여 구한 위치오차는 표적의 수심이 1m, 1.5m, 2m일 때 각각 5.9~27.1cm, 3.2~28.9cm, 3.5~25.8cm였으며, 68.3% 확률원의 반경은 각각 14.6cm, 17.7cm, 17cm였다. 4. 평면배열에 의하여 헛통에서 어군의 행동을 관측한 결과 조류의 방향과 정반대 방향으로 거슬러 유영하면서 자루그물에 입망되는 경향을 나타내었다. 5. 직선 및 평면배열에 의한 어군, 수온, 해저 등과 같은 수중정보는 1,800m까지 원격측정이 가능하였으며, 본 실험의 경우 발신기의 수심이 3m이상이면 어느 곳에서라도 원격측정이 가능하였다.

• 한국전문물리치료학회지
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• 제21권3호
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• pp.73-79
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• 2014

The purposes of the current study were to (1) estimate the inter-rater agreement for visual assessment of scapular downward rotation (SDR), (2) develop the scapular downward rotation index (SDRI) as a method to measure SDR objectively and quantitatively, and (3) analyze the intra- and inter-rater reliability of the SDRI. Twenty subjects with scapular downward rotation syndrome (SDRS) were recruited for this study. The visual assessment and the measurement for the SDRI were conducted by two examiners in two sessions each. The SDRI [$(a-b){\div}a{\times}100$] is calculated with the measurement of two linear distances: One is a perpendicular distance from the root of the scapular spine to the thoracic mid-line (a), and the other is a perpendicular distance from the inferior angle of the scapula to the thoracic mid-line (b). Cohen's kappa coefficient was calculated to estimate the inter-rater agreement for visual assessment. Intra-class correlation coefficients (ICCs) with a 95% confidence interval (CI), the standard error of measurement, and minimal detectable differences were calculated to assess intra- and inter-rater reliability of SDR measurement using the SDRI. The results indicated that the kappa coefficient of inter-rater agreement for visual assessment was fair (${\kappa}=.21$). The intra-rater reliability of SDR measurement using the SDRI was excellent for examiner 1 (ICC=.92, 95% CI=.78~.97) and good for examiner 2 (ICC=.82, 95% CI=.55~.93). The inter-rater reliability was moderate (ICC=.73, 95% CI=.32~.89). These findings showed that SDR measurement using the SDRI for subjects with SDRS may be considered reliable and better than the visual assessment.

• 한국위성정보통신학회논문지
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• 제12권1호
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• pp.34-37
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• 2017

본 논문은 I/Q 채널을 다 이용하여 표적의 후퇴와 접근을 감지하는 연속파 레이다의 신호처리에 대하여 분석한다. 표적이 레이다로부터 접근 혹은 후퇴할 때 Quadrature 신호의 위상이 달라지는 것을 이용하여 물체의 후퇴와 접근을 감지하며, 상용 MMIC칩과 MCU를 이용하여 모듈을 구현하고, MMIC로부터 나온 수신데이터를 분석하여 검증하였다. 또한 사람을 대상으로 접근, 후퇴하는 동작에 대한 신호처리를 MCU를 사용하여 확인하였다. 사용한 주파수는 24.125GHz이며, 송신기 출력전력은 7.2 dBm이다. 실제 구현한 레이다로 최대 검출가능거리는 약 12m를 달성하였다.