• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.529-533
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• 2012

본 연구에서는 실내실험을 통하여, 하안침식을 고려한 망상하천에서 저수로의 이동특성을 조사하며, 2중 퓨리에 해석에 의하여 사주의 거동특성을 분석하였다. 실내실험은 평균입경이 1.4 mm이고, 표준편차가 1.35인 균일사로 10 cm 의 두께로 전체가 균등하게 채워진, 길이가 12 m, 넓이 2 m 수로에서 수행하였다. 각 시간별 하도의 지형변화에 대하여 2 중 Fourier 해석에 의한 지배적인 성분, 즉 모드(mode)의 변화를 분석하였다. 여기서 1-1 mode는 교호사주(alternate bars)이고, 1-2 mode와 2-2 mode는 2차 횡방향 모드로서 중앙 사주(central bars)를 나타낸다. 1-3 mode와 2-3 mode는 한 단면에서 횡방향으로 3개의 사주가 형성된 것(triple row bars)를 나타낸다. 초기에는 1-1 mode인 교호사주가 지배적이지만, 시간이 증가함에 따라, 교호사주인 1-1 mode는 감소하고, 한 단면에서 3개의 사주가 형성되는 2-3 mode가 지배적인 것으로 나타났다. 이러한 원인은 시간이 지나면서 사주가 발달하고, 하안침식이 되면서, 하폭이 증가하여 상대적으로 수심이 감소하면서 복렬사주가 발달하기 때문이며, Colombini 등(1987)이 이론적으로 예측한 결과와 잘 일치한다. 한 단면에서 3개의 모드가 나타나는 것은 하상에서 변화를 일으키는데 중요한 역할을 한다. 직선하도에서 사주의 수가 증가하는 것은 교호사주의 강한 비선형으로 상호작용하기 때문이다.

• 대한기계학회논문집B
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• 제22권4호
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• pp.450-467
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• 1998

The characteristics of the unstable impinging circular jet is investigated based on the frequency characteristics and the sound field of the impinging-tones. Two symmetric modes S1 and S2, associated with low frequency and high frequency respectively, and one helical mode H have been observed. At low speed the S2 mode is dominant and switched by the S1 mode as the speed increases. When the jet speed is high the S1 mode is very active over the impinging distance from half the nozzle diameter to its ten times, while the S2 mode occurs at shorter distance corresponding to stage 2 and 3. The helical mode H seems unstable, likely to be influenced much by the experimental environment, and occurs at relatively high speed with almost the same frequency characteristics as the S2 mode. By estimating the convection speed of the unstable jet, it is found that the ratio of the convection speed to the jet speed decreases with both Strouhal number and Reynolds number and the speed of S2 mode is faster than the Si mode. When the present experimental results are compared with the previous investigations performed for the hole tone and the impinging tone with a small plate, the S1 mode is found to be associated with the ring vortex of large diameter with low speed, but the S2 mode with the vortex of small diameter with high speed. In addition, the frequency is found to be influenced by the nozzle configuration but the characteristics is almost the same. From the impinging distance and frequency range, it can be deduced that S1 mode is related with the jet column mode and S2 mode with the shear mode.

• STI Policy Review
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• 제8권2호
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• pp.23-48
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• 2017

This article advocates for a Mode 3 science policy. Compared to the university research-based Mode 1 knowledge production system and the knowledge application-centric Mode 2 innovation system, Mode 3 can be defined as a system that integrates both Mode 1 and Mode 2-type knowledge production models. In this article, based on the major characteristics of the Mode 3 scientific knowledge production system, I agree with the advocates of Mode 3 that constructing a knowledge society requires an inclusive form of knowledge production and innovation system through the democratization of knowledge production as well as the promotion of social values. Moreover, the mechanisms for creating accountable innovation in the Mode 3 system should be given more attention from the science research and policy communities to make public policy for scientific and technological innovation more reflective of social changes. Similar to the ways that the Mode 1 and Mode 2 scientific knowledge production approaches have influenced the development of science policy models, the Mode 3 scientific knowledge production approach, or Mode 3 science, also has the potential to shape a new science policy model. I will refer to this as Mode 3 science policy. In an effort to conceptualize the democracy- and society-centric Mode 3 science policy model, I will articulate science policy strategies in four science policy domains in South Korea from the context of the Mode 3 science approach. These include (1) evaluation of publicly-funded research activities, (2) valorization of scientific knowledge (that is, enhancement of the value of scientific knowledge through governmental action), (3) development of a science policy decision-making support system, and (4) anticipatory foresight of science, technology and society. When adopting and implementing a Mode 3 science framework, one progressive change is to increase socially desirable innovation such as responsible innovation.

• 한국전자파학회논문지
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• 제23권12호
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• pp.1337-1342
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• 2012

본 논문에서는 RF 스위치 역할을 하는 핀-다이오드를 이용하여 정합 회로의 형상을 변경하는 새로운 형태의 재구성 안테나를 제안하였다. 개발된 안테나는 HSDPA 대역(2.1~2.2 GHz), WiBro WiFi 대역(2.3~2.5 GHz)에서 Mode 1과 Mode 2의 두 가지 모드로 동작할 수 있도록 하였으며, polyarcylate 기판의 양면을 이용하여 제작 및 측정을 하였다. 측정 결과, Mode 1과 Mode 2의 동작 주파수에서 547 MHz($S_{11}$ <-3 dB, 2.035~2.582 GHz), 600 MHz($S_{11}$ <-3 dB, 2.2~2.8 GHz)의 대역폭을 보였으며, 각각 -4.4 dBi, -4.5 dBi의 x-y 평면 평균 수직 복사 성능을 보였다.

• 산업경영시스템학회지
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• 제42권4호
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• pp.69-75
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• 2019

Remotely Piloted Aircraft (RPA) controls as a type of unmanned aerial vehicle (drone) is growing rapidly and its flight controller stick disposition is required standardization. We should standardize RPA drone flight control disposition because the flight pilot of RPA is hard to be trained so the flight controller stick differences impairs safety and wastes time and effort of flight controller industry. So this study researches the on-going standardization of RPA drone flight control disposition in Korea and foreign countries. Also this paper analyzes and researches of expert about RPA drone flight controller function and application of flight control mode. I accomplished expert research about standardization plan of unmanned flight control mode and confirm the necessity. Nowadays mode1 and 2 are mostly used in Korea so I carried out preference investigation for two modes. There were 4 preferences choices of RPA drone control mode necessity (importance) and recommendation of standardization modes. They answered that necessity of standardization is important considering pilot training, flight safety and positive development of drone industry. The result of standardization mode preference is that they prefer mode 2 (drone maker 86%, training facilities and research facilities 58%, government bureau 60%). Overall preference result shows that mode 1 24%, mode 1&2 16%, mode 2 60%. So they preferred mode 2 by 60%. The differences between two modes are the direction of throttle and pitch. Direction of throttle and pitch operate opposite way. They prefer mode 2 because mode 2 has similarities of manned flight control mode. Significance of this study is that it showed the necessity of standardization and flight control preference in a quantitative way. It will help drone standardization in related industries and development direction near future.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 1부
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• pp.749-753
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• 2008

자기수용감각은 신체 내부에서 폼의 발란스, 근육의 강도, 민첩성을 이용하여 공간의 위치나 관절의 움직임을 조절하는 능력으로 정의된다. 기존의 연구에서는 자기수용감각을 발달시키기 위하여 reaching 훈련을 이용한 시각적인 feedback을 제시하여 훈련을 하고 feedback을 차단하고 측정하는 방법이 사용했지만 시각적인 feedback이 있는 상황은 자기수용감각만 유도할 수 없는 문제점이 있다. 가상현실 기술은 훈련 동안 실시간으로 시각적인 feedback을 다양하게 제공하는 것으로 기존의 연구의 문제점을 해결할 수 있다. 본 연구에서는 가장현실 기술을 이용한 자기수용감각을 발달시키기 위한 훈련 및 평가시스템을 개발하고 파일럿 스터디를 하였다. 가상환경 task는 3개로 구성되었다. mode 1은 신체 움직임을 실시간으로 시각적인 feedback을 제시하는 환경이다. mode 2는 피험자의 반응에 의해서만 신체 움직임에 대한 시각적인 feedback을 제시하는 환경이다. mode 3응 시각적인 feedback을 제시하지 않는 환경이다. 가상환경의 task는 각 mode에서 3지점을 한 번씩 수행하는 것을 1회기로 5회기씩 수행하였다. 본 연구의 결과에서, target을 획득하기 위하여 이용하는 시간은 mode 3에서 mode보다 더 짧게 소요 되었다.(P=0.001). mode 2와 mode 3에서 1회기에서는 상관관계를 가지고 2-5회기 동안에는 mode 2와 mode 3에서 상관관계가 보이지 않았다(p = 0.012). mode 1의 환경에서는 훈련에 필요한 자기수용감각보다 시각적인 feedback에 의한 훈련이 진행되는 것을 볼 수 있다. mode 2는 첫 회기에서 자기수용감각에 의한 시각적인 feedback을 제공받을 수 있기 때문에 자기수용감각 훈련을 수행할 수 있다. 추후 연구는 시스템의 타당성 검증과 임상실험을 통한 훈련과 평가를 할 계획이다.

• 멤브레인
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• 제21권3호
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• pp.263-269
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• 2011

침지식 막결합형 연속회분식 생물반응기에서 폐수의 도입단계가 제거효율과 여과성능에 미치는 영향을 조사하였다. 호기성 단계의 초기에 공급할 경우(Mode-1)와 무산소 단계의 초기에 공급할 경우(Mode-2)에 대하여 89일 동안 동시에 운전하였다. COD 제거효율과 여과성능은 2가지 운전방식 간에 큰 차이가 없었다. 그러나 영양염류(총질소와 총인)의 제거효율에 있어서 Mode-2가 Mode-1에 비해 보다 효과적이었다. Mode-2의 경우 COD, 총질소 및 총인의 제거율은 각각 99.1, 73.3 및 77.7%이었다.

• 한국의학물리학회지:의학물리
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• 제27권3호
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• pp.169-174
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• 2016

The aim of this study is to investigate the delivery accuracy of intensity-modulated radiation therapy (IMRT) plans in the two-headed mode of the ViewRay$^{TM}$ system in comparison with that of the normal operation treatment plan of the machine. For this study, a total of eight IMRT plans and corresponding verification plans were generated (four head and neck, two liver, and two prostate IMRT plans). The delivered dose distributions were measured using ArcCHECK$^{TM}$ with the insertion of an ionization chamber. We measured the delivered dose distributions in three-headed mode (normal operation of the machine), two-headed mode with head 1 disabled, two-headed mode with head 2 disabled, and two-headed mode with head 3 disabled. Therefore, a total of four measurements were performed for each IMRT plan. The global gamma passing rates (3%/3 mm) in three-headed mode, head 1 disabled, head 2 disabled, and head 3 disabled were $99.9{\pm}0.1%$, $99.8{\pm}0.3%$, $99.6{\pm}0.7%$, and $99.7{\pm}0.4%$, respectively. The difference in the gamma passing rates of the three- and two-headed modes was insignificant. With 2%/2 mm, the rates were $96.6{\pm}3.6%$, $97.2{\pm}3.5%$, $95.7{\pm}6.2%$, and $95.5{\pm}4.3%$, respectively. Between three-headed mode and head 3 disabled, a statistically significant difference was observed with a p-value of 0.02; however, the difference was minimal (1.1%). The chamber readings showed differences of approximately 1% between three- and two-headed modes, which were minimal. Therefore, the treatment plan delivery in the two-headed mode of the ViewRay$^{TM}$ system seems accurate and robust.

• Journal of the Optical Society of Korea
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• 제20권1호
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• pp.135-139
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• 2016

I propose a vector passive harmonic mode-locked fiber laser based on topological insulator Bi2Se3 interacting with a fiber taper with a diameter of 7 μm. The particles of topological insulator are deposited uniformly onto the fiber taper with light pressure effect. By incorporating the fabricated saturable absorber into an Er-doped fiber laser cavity, stable mode-locked fiber is obtained. Due to the intense evanescent field of the fiber taper, strong confinement of light enhances the nonlinearity of the laser cavity, and passive harmonic mode-locking is performed. I observe a maximum harmonic mode-locking of 356th, corresponding to a frequency of 3.57 GHz. The pulse duration is 824 fs, and the full width at half maximum of the spectrum is about 8.2 nm. The polarization dependent loss of the saturable absorber is ~ 2.5 dB in the wavelength range of the C band. As the cavity contains no other polarization dependent device, the mode-locked laser is functioning in the vector state. The harmonic order vs pump power is investigated. To the best of our knowledge, this report is the highest frequency mode-locked fiber laser based on Bi2Se3. Experimental results indicate that the topological insulator Bi2Se3 functioning with a thin fiber taper is effective for vector harmonic mode-locking.

• 약학회지
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• 제43권6호
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• pp.776-781
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• 1999

Dockings of 4,5-diarylpyrroles into cyclooxygenase-1 and cyclooxygenase-2 were carried out by GOLD program. The sulfonyl groups bonded to 5-phenyl ring of 4,5-diarylpyrroles are directed to Arg513 of COX-2 and Tyr385 of COX-2 docking modes of pyrroles are different from COX-1. Tyr385 and Arg120 of COX-1 and COX-2 have been recognized as important residues. Val523 of COX-2 may be also important. A new COX-2 selective inhibitors could be designed from the docking study.