• 환경생물
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• 제32권2호
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• pp.118-128
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• 2014

경기만에서 분리된 Skeletonema marinoi-dohrnii complex의 생장률을 구하기 위하여 영양염이 제한되지 않는 조건 하에서 무균 회분배양으로 넓은 범위의 광조건($5{\sim}500{\mu}mol\;m^{-2}s^{-1}$)과 수온($2{\sim}35^{\circ}C$)에 걸쳐 실험하였다. 실험 결과로부터 온도와 광이 각각 $26.1^{\circ}C$, $197{\mu}mol\;m^{-2}s^{-1}$인 최적조건에서 이 종의 최대 ${\mu}_{max}$는 $2.48d^{-1}$을 보였다. 또한 실제 해역에서 Skeletonema 종들의 온도에 따른 자원경쟁을 고려할 때 $5{\sim}15^{\circ}C$에서 S. marinoi-dohrnii complex의 상대적으로 높은 생장률 ($0.79{\sim}1.61d^{-1}$)은 늦겨울에서 봄철에 대증식을 일으킬 수 있음을 시사한다. 이 결과는 해양생태계 모델의 정확성과 실재성을 개선하는데 기초자료로 활용될 수 있다.

• 대한기계학회논문집B
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• 제32권11호
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• pp.832-840
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• 2008

Ablation occurs at irradiance beyond $10^9\;W/cm^2$ with nanosecond and short laser pulses focused onto any materials. Phenomenologically, the surface temperature is instantaneously heated past its vaporization temperature. Before the surface layer is able to vaporize, underlying material will reach its vaporization temperature. Temperature and pressure of the underlying material are raised beyond their critical values, causing the surface to explode. The pressure over the irradiated surface from the recoil of vaporized material can be as high as $10^5\;MPa$. The interaction of high power nanosecond laser with a thin metal in air has been investigated. The nanosecond pulse laser beam in atmosphere generates intensive explosions of the materials. The explosive ejection of materials make the surrounding gas compressed, which form a shock wave that travels at several thousand meters per second. To understand the laser ablation mechanism including the heating and ionization of the metal after lasing, the temporal evolution of shock waves is captured on an ICCD camera through laser flash shadowgraphy. The expansion of shock wave in atmosphere was found to agree with the Sedov's self-similar spherical blast wave solution.

• Ocean and Polar Research
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• 제23권4호
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• pp.401-410
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• 2001

Global climate change will alter many such properties of the Southern Ocean as temperature, circulation, stratification, and sea-ice extent. Such changes are likely to influence the species composition and activity of Antarctic marine microorganisms (protists and bacteria) which playa major role in deter-mining the concentration of atmospheric $CO_2$ and producing precursors of cloud condensation nuclei. Direct impacts of climate change on Antarctic marine microorganisms have been determined for very few species. Increasing water temperature would be expected to result in a southward spread of pelagic cyanobacteria, coccolithophorids and others. Growth rates of many species would be expected to increase slightly but nutrient limitation, especially micronutrients, is likely to result in a negligible increase in biomass. The extent of habitats would be reduced for those organisms presently living close to the upper limit of their thermal tolerance. Increased UVB irradiance is likely to favour the growth of those organisms tolerant of UVB and may change the trophic structure of marine communities. Indirect effects, especially those as a consequence of a diminution of the amount of sea-ice and increased upper ocean stratification, are predicted to lead to a change in species composition and impacts on both trophodynamics and vertical carbon flux.

• 한국태양에너지학회 논문집
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• 제30권2호
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• pp.10-15
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• 2010

The experimental study was conducted to optimize the system dissipating properly heat from the in-situ solar panel installed on the roof. For this purpose, six 12-Watt panels, which were consisted of the different design conditions such as containing phase change material(PCM), changing the array of the aluminum fin and honeycomb at the back of the panel, were tested. PCM, which had $44^{\circ}C$ melting point, was chosen in this study. In order to enhance absorbing and expelling heatin PCM, profiled aluminum fin was placed either inward oroutward from the panel. Furthermore, Aluminum honeycomb is imbedded in the back container to find if it would improve the thermal conductivity of PCM. During the experiment, there were ranged to $26^{\circ}C\sim32^{\circ}C$ for outdoor temperature and $700W/m^2\sim1000W/m^2$ for irradiance. As a result, the solar panel, combined with honeycomb and outward fins with PCM instead of placing the fins inward, is showing the best performance in terms of controling panel temperature and its efficiency.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.210-211
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• 2007

Amid booming PV(photovoltaic) industry, BIPV(Building Integrated PV) is one of the best fascinating PV application technologies. To apply PV in building, variable factors should be reflected such as installation position, shading, temperature effect and so on. Especially a temperature should be considered, for it affects both electrical efficiency of PV module and heating and cooling load in building. Transparent PV modules were designed as finished material for spandrels are presented in this paper. The temperature variation of the modules with and without air gap and insulation were compared and analyzed. The results showed that the module with air gap and insulation has a much larger temperature variation than another transparent module. The temperature of the module reached by 55degree C under vertical irradiance of lower 500$W/m^2$. And the temperature difference between these modules was about 15degree C. To analyze the output performance of module according to temperature variation, separate module was manufactured and measured by sun-simulator. The results showed that 1 degree temperature rise reduced about 0.45% of output power.

• ALGAE
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• 제35권2호
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• pp.123-131
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• 2020

Sargassum macrocarpum is a rich source of anti-inflammatory compounds. Recently, one of the compounds, tuberatolide B, has been reported as a functional anti-inflammatory additive for foods and nutraceuticals. The artificial seeding, growth and maturation of S. macrocarpum were investigated from May 2018 to September 2019. Indoor culture experiments for induction of egg release were conducted at temperatures of 17, 20, 23, and 26℃ and irradiances of 0, 10, 20, 40, and 80 μmol photons m^-2 s^-1 under 14 : 10 h (L : D) photoperiod. Within a given treatment combination, higher temperatures and irradiance levels favoured the maturation of receptacles in S. macrocarpum. Using artificial temperature and irradiance control, thalli matured one month earlier than thalli in nature. Under natural condition, receptacle formation began in April, and the eggs were released in June and July. The release of eggs from the receptacles was promoted at 17-20℃ and 40-80 μmol photons m^-2 s^-1, and the fastest growth of germlings occuring at 15-17℃ and 40 μmol photons m^-2 s^-1. For mature thalli, 300 g wet-weight was sufficient to seed 100 m of seed string. Thalli grew to 10.5 ± 2.6 cm in length at a density of 6.7 ± 3.3 individuals m^-1 after 1 year of cultivation, from germination. This study demonstrates that it is possible to cultivate S. macrocarpum for the production of anti-inflammatory products.

• 한국항해항만학회지
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• 제35권3호
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• pp.265-270
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• 2011

본 연구는 건물에너지 효율 향상을 위한 목적으로 기상데이터 변화에 따른 건물 냉 난방부하량을 예측하고 결과를 비교 분석한 것으로, 연구 성과는 다음과 같다. 1)기상청에서 입수데이터를 평가툴인 ESP-r에 활용할 수 있도록 항목별 기상데이터를 개발하였다. 표준기상 데이터의 외기온도, 습도, 풍속은 대부분의 경우 기상청데이터 보다 크거나 높았다. 수평면전일사량은 기상청데이터가 높았고, 직달일사량은 겨울철에는 표준기상데이터가, 여름철에는 기상청데이터가 많은 것으로 나타났다. 2)대학교 캠퍼스 내에 신축된 후생복지관을 대상으로 한 시뮬레이션 결과, 최대난방부하의 경우 표준년도, 2006년, 2009년이 비슷한 반면 2007년은 표준년도 대비 81%, 2008년은 96% 수준이었고, 연간난방부하는 2006년, 2008년의 순으로 난방수요가 많았다. 한편, 냉방부하의 경우에는, 상대적으로 최대냉방부하가 큰 2007년, 2009년의 연간 냉방부하보다 최대냉방부하가 가장 적은 2008년의 연간냉방부하가 더 큰 결과를 보였다. 3)냉 난방기기의 상당시간가동률을 평가한 결과, 표준년도의 최대부하대비 상당시간가동률은 2006~2009년이 표준년도에 비해 대부분 가동률이 낮았다.

• 한국태양에너지학회 논문집
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• 제38권6호
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• pp.51-63
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• 2018

Nowadays the bifacial PV system market and its applications are increasing rapidly. The performance of the bifacial PV system take advantage of its rear surface irradiance. Also, the ground albedo, PV module tilt and azimuth, PV module installation height, shading effect and module temperature are factors of bifacial PV system performance. This paper investigates how the performance of bifacial PV system is influenced by above factors. First, we analyzed the energy yield depending on PV module installation by simulation. Secondly, we compare energy performance evaluation of monofacial and bifacial module on different weather condition by experiment. Thirdly, we tested the albedo effect and checked operating characteristics using Dupont Tyvek material for the bifacial PV module. Fourthly, we check the shading effect of bifacial PV module on bypass diode operating. Finally, we applied the bifacial PV module in the nearby subway station for the noise reduction barrier using a qualified simulation program. In summary, we confirm that the energy performance superiority of the bifacial PV module has a lot of application use including road. Also, we have confirmed the bifacial module and inverter design should be considered by rear surface irradiance.

• Current Photovoltaic Research
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• 제11권1호
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• pp.27-33
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• 2023

In this paper, a machine learning model by using a regression algorithm is proposed to estimate the power generation performance of the BIPV system. The physical model formula for estimating the generation performance and the proposed model were compared and analyzed. For the physical model formula, simple efficiency model, temperature correction model, and regressive physics model for changing an irradiance were used. As a result, when comparing the regressive physics model for changing an irradiance and the proposed model with the actual generation measured data, the respective RMSE values are 0.1497 kW, 0.0451 kW and the accuracy values are 86.44%, and 96.56%. Therefore, the proposed model implemented in this experiment can be useful in estimating power generation.

• 한국해양학회지:바다
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• 제3권2호
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• pp.80-89
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• 1998

남극 내만 생태계에 서식하는 식물플랑크톤의 계절에 따른 분포 및 생리상태, 그리고 상호관계를 알아보기 위하여 아남극에 위치한 Maxwell 만과 Marian 소만에서 1994년 2월부터 1994년 12월까지 물리, 화학적 환경요인과 식물플랑크톤의 색소량, 일차생산력을 조사하였다. 조사시기 동안 관측한 chlorophyll a의 농도는 미검출 수준(not detected)~3.03 ${\mu}g/l$ (평균 0.63 ${\mu}g/l$)의 비교적 큰 변화를 보였고, 일차생산력은 0.53~18.95 mg C/$m^3{\cdot}day$를 기록하였으며, 수층적분한 식물플랑크톤의 일차생산력은 41.28~560.20 mg C/$m^3{\cdot}day$의 범위를 보였다. 식물플랑크톤의 생물량은 일사량과 양의 상관관계를 보였고($r^2$=0.29, p < 0.01), 일차생산력은 일사량과 매우 밀접한 관련이 있었으나($r^2$=0.85, P < 0.001), 온도와 영양염은 식물플랑크톤 군집을 조절하는데 기여하지 않았다.