• 한국전기전자재료학회논문지
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• 제33권4호
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• pp.255-262
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• 2020

Grain boundaries play a major role in determining device performance, particularly of polysilicon-based photodetectors. Through the post-annealing of as-deposited polysilicon and then, the analysis of electric behavior for a metal-polysilicon-metal (MSM) photodetector, we were able to identify the influence of grain boundaries. A modified model of polysilicon grain boundaries in the MSM structure is presented, which uses a crystalline-interfacial layer-SiO_x layer- interfacial layer-crystalline system that is similar to the Si-SiO₂ system in MOS device. Hydrogen passivation was achieved through a hydrogen ion implantation process and was used to passivate the defects at both interfacial layers. The thin SiO_x layer at the grain boundary can enhance the photosensitivity of an MSM photodetector by decreasing the dark current and increasing the light absorption.

• 아시안잔디학회지
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• 제15권1호
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• pp.15-20
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• 2001

Two types of annual bluegrass have been reported, and those consist of annual type (Poa annua ssp. annua) and perennial type (Poa annua ssp. reptans). As a weed, annual bluegrasses are commonly found in putting greens and fairways in many golf courses. Due to its strong competitiveness such as tremendous seed reproduction rate a year, prostrate growth habit, and no herbicide availability, annual bluegrasses have been considered as one of the most hard-to-control weeds in turf management systems. A growth chamber study was conducted to determine seed dormancy and to understand seed germination characteristics of annual bluegrass (Poa annua ssp. annua). Freshly harvested seeds showed 80 and 55% germination at 30 and $35^{\circ}C$, respectively, indicating that the optimum temperature of annual bluegrass is $30^{\circ}C$. However, the seed germination occurred only under light condition at any given temperature. This result demonstrated that light is prerequisite for the seed germination, and no primary dormancy of annual bluegrass seed exists. Secondary seed dormancy induced by unfavorable temperatures and dark condition was broken through 4 to 6 wk-storage at $4^{\circ}C$ with moisture, and the stored seeds germinated at $20^{\circ}C$ even under the dark. In red and far-red light trial, fresh seeds resulted in 40% germination under red while no seed germination occurred under far-red light condition, indicating that phytochrome Pr and Pfr could be related to annual bluegrass seed germination. When the far-red light replaced the red the germination was recovered, but this reversibility did not reach to the germination level under the red light only. This result implied that other lights than red and far-red would play an important role on seed germination of annual bluegrass.

• 한국식품영양과학회지
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• 제26권2호
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• pp.203-208
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• 1997

국산 대두의 항산화 효과를 확인하고 그 원인 물질을 규명하기 위하여 노란콩, 밤콩, 검정콩, 소립검정콩을 각각 콩전체, 콩껍질과 속으로 분리하여 실험한 결과, 콩전체의 경우 노란콩 보다 밤콩, 검정콩, 소립검정콩 등의 색이 짙은 콩의 항산화 효과가 높았고 이들을 껍질과 속으로 분리하여 항산화효과를 측정한 결과 콩 속의 항산화 효과는 네종류의 콩에서 유사한 것으로 나타났으나 껍질의 경우 노란콩 보다 밤콩, 검정콩, 소립 검정콩 등의 색이 짙은 콩껍질에서 높은 항산화 효과를 나타내어서 콩의 항산화 효과에는 콩껍질에 함유되어 있는 색소물질이 중요한 역할을 하는것으로 나타났다. 콩의 짙은 색의 주요 색소성분인 anthocyanin 함량을 측정한 결과 소립검정콩과 검정콩의 anthocyanin 함량이 높았고 밤콩과 노란콩은 적게 나다났다. 콩의 항산화효과의 주요물질을 분리하기 위하여 핵산, 메타놀 및 물로 추출하여 항산화 효과를 측정한 결과 80% 메타놀추출물에서 네종류의 콩 모두 강한 항산화 효과를 나타내었다. 콩의 항산화 원인 물질인 total phenol 함량을 측정한 결과 노란콩 보다 밤콩, 검정콩, 소립검정콩에서 높은 함량을 나타내었고 용매별 추출물 중에서는 메타놀추출물에서 그 함량이 높아서 콩의 항산화 효과와 total phenol 함량은 일치하는 것으로 나타났다.

• 한국환경농학회지
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• 제25권2호
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• pp.109-117
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• 2006

Photoinhibition and photoprotection of PSII in the leaves of hot pepper (Capsicum annuum L.) grown in Hoagland solution and Tap water were compared. Though changes in the rates of $O_2$ evolution as a function of photon fluence rate (PFR) were comparable, the rates of respiration in the dark was 3 times higher in the Hoagland solution grown leaves than in the Tap-water grown ones. Compared to Hoagland solution grown plane, PSIIs of Tap water grown pepper leaves were more susceptible to photoinhibitory light treatment. In order to inactivate functional PSII to the same extents, Hoagland solution grown plants required almost 2-fold high light $(1600{\mu}molm^{-2}s^-)$ treatment than those of Tap water $(900{\mu}molm^{-2}s^-)$. Interestingly, the remaining fraction of PSII in Hoagland grown pepper was able to survive under prolonged illumination in the presence of lincomycin, which probably means that the growth condition of plant seemed to have an effect on the recovery of PSII from light stress. When PSII was severly photoinactivated at a chilling temperature, recovery was observed only if the residual functional PSII were not inhibited with DCMU, Nigericin and MV during recovery. In conclusion, PSIIs grown in the Hoagland solution was more resistant to excess light than in the Tap water grown one and the recovery of PSII from photodamage was more efficient in Hoagland grown pepper leaves than Tap water grown one, which means that the increased dark respiration may play a important role in the protection of PSII from photoinhibition by helping repair photosynthetic proteins (in particular, the D1 protein of PSII) degraded by photoinhibition.

• 한국게임학회 논문지
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• 제17권5호
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• pp.51-60
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• 2017

미구엘 시카트(M. sicart)는 불쾌한 게임 디자인이 디자이너와 플레이어간의 상호작용을 발생시키며 이를 통해 게임이 예술의 영역에서 해석될 수 있음을 시사 하였다. 본 논문에서는 이 불쾌한 게임디자인을 고프먼의 프레임 이론에 바탕하여 재해석한다. 보편적인 게임학이 추구하는 '사용자 중심'적 게임 디자인은 게임의 플레임에 몰입하여 사용자 경험과 게임의 프레임에 일치감을 더하는 긍정적 다운키잉(Positive Down-keying)을 추구한다고 볼 수 있다. 반면에 불쾌한 게임 디자인은 게임의 프레임에 대한 플레이어의 관점에 '혼란함'을 주어 게임에 대한 반성적 관점을 가질 수 있도록 해준다. 예술의 영역에서 게임을 해석하기 위한 방편에서 불쾌한 게임 디자인을 정의했던 시카트 이론은 불쾌한 게임 디자인과 전형적인 게임 디자인을 나눠서 보지만 플레임 분석을 통한 불쾌한 게임 디자인은 게임 플레이에 대한 플레이어의 반성적 시각을 환기시키는 장치 혹은 테크닉으로 기존의 게임디자인과 관계할 수 있음을 알려주고 있다.

• 수면정신생리
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• 제21권2호
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• pp.51-60
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• 2014

A 'circadian rhythm' is a self-sustained biological rhythm (cycle) that repeats itself approximately every 24 hours. Circadian rhythms are generated by an internal clock, or pacemaker, and persist even in the absence of environmental time cues, collectively termed 'zeitgebers.' Although organisms generate circadian rhythms internally, they are entrained by environmental stimuli, particularly the light-dark cycle. Measurement of the endogenous melatonin rhythm provides relatively reliable surrogate way of assessing the timing of the internal circadian clock. Also, core body temperature and cortisol can be used as markers of circadian rhythms. The sleep-wake cycle, body temperature, and melatonin rhythm have a stable internal phase relationship in humans and other diurnal species. They play an important role in controlling daily behavioral rhythms including task performance, blood pressure, and synthesis and secretion of several hormones. In this review, we address not only the properties, methods of measurement, and markers of circadian rhythms, but also the physiological and psychological importance of human circadian rhythms.

• 한국환경과학회지
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• 제11권11호
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• pp.1173-1181
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• 2002

The present study was undertaken to investigate the effect of low temperature and salicylic acid(SA) on the chilling tolerance of acclimated and nonacclimated cucumber(Cucurmis sativus L.) seedlings. The acclimation phenomenon was characterized in chilling-sensitive cucumber seedlings and found to have a significant effect on the survival and shoot dry weights. The injuries experienced by the acclimated seedlings in the third leaf stage were on average smaller by half than those experienced by the nonacclimated seedlings. Chilling also caused a large increase in the free proline levels, regardless of the acclimation status. Exogenous treatment with SA(0.5mM) resulted in improved growth and survival of the nonacclimated chilled seedlings, indicating that SA induced chilling tolerance and SA and acclimation had common effects. The application of cycloheximide in the presence of SA restored the acclimation-induced chilling tolerance. The elevated proline level observed in the cold-treated and SA-treated plants was more pronounced in the light than in the dark at a chilled temperature, indicating that endogenous proline may play a role in chilling tolerance by stabilizing the water status in response to chilling. From these results it is suggested that SA provided protection against low-temperature stress by increasing the proline accumulation, and pre-treatment with SA may induce antioxidant enzymes leading to increased chilling tolerance.

• 한국환경과학회지
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• 제9권3호
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• pp.267-273
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• 2000

In order to understand the impact for decomposition of blue-green algae Microcystis on water quality, the algae were cultivated with collection of natural population during approximately one month, when water-bloom of Microcystis dominated at August 31, 1999 in the lower part of the Okchon Stream. The enrichment of inorganic NㆍP nutrients didn't in algal assay and the effect of Microcystis on water duality was assessed from the variation of nutrients by algal senescence. Microcystis population seemed to play a temporary role of sink for nutrients in the water body. Initial algal density of Microcystis was 2.3×10/sup 6/ cells/㎖. When Microcystis population died out under light condition, algal NㆍP nutrients between 9∼12 days affected to increase of biomass after reuse by other algal growth as soon as release to the ambient water. However, cellular nutrients under dark condition were almost moved into the water during algal cultivation. NH₄, NO₃ and SRP concentration were highly increased with 160, 17 and 79 folds, respectively relative to the early. As a result, the senescence of Microcystis population seemed to be an important biological factor in which cause more eutrophy and increase of explosive algal development by a lot of nutrients transfer to water body. There are significantly observed an effort of reduce for production of inner organic matters such a phytoplankton as well as load pollutants from watershed in side of the water quality management of reservoir.

• 천문학회지
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• 제33권1호
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• pp.1-17
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• 2000

We have performed extensive simulations of response of gaseous disk in barred galaxies using SPH method. The gravitational potential is assumed to be generated by disk, bulge, halo, and bar. The mass of gaseous disk in SPH simulation is assumed to be negligible compared to the stellar and dark mass component, and the gravitational potential generated by other components is fixed in time. The self-gravity of the gas is not considered in most simulations, but we have made a small set of simulations including the self-gravity of the gas. Non-circular component of velocity generated by the rotating, non-axisymmetric potential causes many interesting features. In most cases, there is a strong tendency of concentration of gas toward the central parts of the galaxy. The morphology of the gas becomes quite complex, but the general behavior can be understood in terms of simple linear approximations: the locations and number of Lindblad resonances play critical role in determining the general distribution of the gas. We present our results in the form of 'atlas' of artificial galaxies. We also make a brief comment on the observational implications of our calculations. Since the gaseous component show interesting features while the stellar component behaves more smoothly, high resolution mapping using molecular emission line for barred galaxies would be desirable.

• 비교문화연구
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• 제26권
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• pp.249-272
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• 2012

Diaspora studies has become one of the fastest growing field in the humanities over the past several decades, and the use of term diaspora has been widening to include almost any population on the move. Diaspora literature not only mirrors but actively incorporates this new notion of diaspora with characters "at the threshold" navigating new territories and identities. Querying how diaspora studies intersects with theatre and performance, this paper attempts to probe how recent Korean American drama parallels and promotes diaspora studies' radical departure from traditional notions of identities and territories. For this purpose, this essay 1) examines theoretical affinities between diaspora studies and performance studies 2) investigates how Sung Rno's plays, Cleveland Raining and wAve, explore and embody multiple and evolving meanings of Korean diaspora on the stage 3) examines how theatre can create the third space that transcends both Korean and American nationalism and 4) speculates possibilities of reframing Asian American Studies as Asian diaspora studies. Korean American characters in Rno's play redirect diasporic identities, as their concern gradually moves from "where I come from" to "where I go to." Instead of remaining in the dark as a mere spectator, both Rno and his characters choose to be 'on' the stage where they can imagine, perform, and realize (however temporarily) "unimaginable community" by confronting their own social, political, and cultural ambivalence. Stage, the threshold between reality and fiction, Korea and America, and past and future, becomes their true 'home' where they incubate and precipitate "nation in transformation" that Yan Haiping argues for as "another transnational."