• 한국산업융합학회 논문집
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• 제26권6_3호
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• pp.1215-1221
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• 2023

According to the study and experiments performed on the Improvement of Maintaining Temperature of Aviation Dangerous Goods, a conclusion was drawn that clear technical guidelines should be established from the design and assembly stage of temperature-controlled packaging, taking into account actual transportation environment. In particular, profiles consisting of only two types of summer and winter are difficult to adjust flexibly in transportation process with severe weather and temperature changes such as spring and fall. To this end, there is a need to establish a compromise profile configuration for summer and winter. It was also found that the condition of the refrigerant, temperature control, and the speed of the packaging operation have a significant impact on maintaining constant temperature. Therefore, all packing operations need to be completed within a short period of time in the environment close to the target temperature. The current packing instructions provided by packaging manufacturers do not provide precise instructions on post-conditioning, but the experiments in this study confirmed that post-conditioning is very important for maintaining the target temperature, so it is necessary to provide precise legal packing technical instructions.

• 수산해양기술연구
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• 제26권3호
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• pp.254-264
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• 1990

수영만을 포함한 부산 지방 안개발생의 특징 및 안개 발생에 대한 부산 연안의 역할을 최근 5개년(1984~1988)의 기상 관측자료 및 지상 일기도, 그리고 해양관측자료를 사용하여 조사하였다. 또한 1989년 7월 한 달 동안 수영만에서 관측한 일기상 자료와 표면 수온을 부산지방의 일기상 자료, 표면수온과 비교하였다. 부산 지방의 안개는 5, 6, 7월에 집중적으로 발생하며, 안개 발생시의 주풍향은 수증기 공급이 용이한 남서풍 및 북동풍이었다. 안개 발생과 관련된 기압계 유형은 봄철(3, 4, 5월)이 pattern 7 (이동성 고기압형), 여름철(6, 7, 8월)이 pattern3(정체전선인 33$^{\circ}$N미만에 위치한 형)과 pattern 10(정체전선이 33~36$^{\circ}$N사이에 위치한 형)이었다. 또한 이류무의 발생은 전층 (850~500mb)에 걸친 대기 불안정도의 증가 보다는 하층 대기 (850~700mb)의 한.온 이류와 해표면의 난.한 수온과의 관계에 더 많은 관련성이 있었다. 내륙 지방인 대구 지방의 안개는 강한 야간 복사 냉각에 의해서 가을철 새벽에 발생하나 해안 지방인 부산은 남풍 계열의 바람이 부는 늦봄에서 여름철(5, 6, 7월)에 다량의 수증기 유입으로 높은 상대습도를 가지게 되어 대기가 약간의 복사 냉각에 의해서도 쉽게 과포화에 이르기 때문에 5, 6, 7월에 집중적으로 발생했다. 수영만과 부산지방의 일기상 자료, 표면 수온 및 안개발생일 등은 거의 비슷하며 안개 발생 mechanism 역시 거의 일치한다고 생각된다.

• Journal of Dairy Science and Biotechnology
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• 제34권1호
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• pp.37-41
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• 2016

본 연구에서는 착유시간에 따른 우유 및 환원유 내 멜라토닌 및 코티솔 농도 변화를 살펴보았고, 이를 바탕으로 긴장완화 및 수면의 질 개선 측면에서의 우유의 기능성 식품으로써의 개발 가능성을 탐색하였다. 연구 결과, 명기에 비해 일출전 암기에 착유한 우유에서 멜라토닌 농도가 유의적으로 높았다. 환원유 내 멜라토닌 농도 또한 우유와 동일한 일주기 리듬을 보였으나, 전반적으로 우유에 비해 멜라토닌 농도가 높은 것을 확인할 수 있었다. 이에 반해 빛 이외에도 운동, 스트레스 등과 같은 요인에 의해 영향을 받는 코티솔은 착유시간에 따른 유의적 차이를 보이지 않았다. 하지만 개체간 변이가 크지 않다고 가정하였을 때, 동지에 비해 하지에 착유한 우유 및 환원유 내 코티솔 농도가 유의적으로 높았다. 이러한 연구 결과를 바탕으로 할 때, 집유 시간을 조정하여 생산한 야간 착유 우유는 내인성 멜라토닌이 풍부한 식품이며, 수면유도에 도움을 줄 수 있는 기능성 식품으로써의 개발 가능성을 가지고 있는 것으로 사료된다. 하지만 본 연구는 착유시간에 따른 원유 및 환원유 내 멜라토닌 농도의 차이만을 보여줬다는 점에서 한계를 가진다. 그러므로 착유시간에 따른 이러한 차이가 실질적으로 우유를 섭취하였을 때, 체내의 수면유도 생리활성에 영향을 미치는지 추가적으로 살펴볼 필요가 있다. 또한, 계절에 따른 우유 내 각 호르몬의 변화를 정확히 파악하기 위하여 동일한 개체를 대상으로 한 추가 연구가 필요하다.

• 한국건설관리학회논문집
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• 제16권4호
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• pp.80-88
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• 2015

건설공사 중 옥외에서 수행되는 공종은 기온, 강우, 풍속 등 기후요소에 의한 작업불능일이 다수 발생한다. 특히, 지구온난화로 인하여 공기산정 시 날씨예측이 어려워져 공기지연 등의 피해는 좀처럼 줄지 않고 있는 실정이다. 이 연구에서는 BCP분석을 통해 인천지역의 연평균기온, 연평균 최고기온 및 연평균 최저기온의 급격한 변화시점을 파악하였으며, 그 시점을 기준으로 하절기 및 동절기 작업불능일 증감추이를 비교분석하였다. 그 결과, 1988년과 1998년에 연평균기온이 급격하게 변화한 것으로 나타났다. 그 두 시점 이후에 하절기의 작업불능일은 증가하고 동절기의 작업불능일은 감소하는 경향이 뚜렷하게 나타났다.

• 지질공학
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• 제26권1호
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• pp.1-13
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• 2016

Groundwater flow paths and groundwater ages at a radioactive waste repository located in a coastal area of South Korea were evaluated using the hydrochemical and hydrogeological characteristics of groundwater, surface water, rain water, and seawater, as well as by numerical modeling. The average groundwater travel time in the top layer of the model, evaluated by numerical modeling and groundwater age (34 years), approximately corresponds to the groundwater age obtained by chlorofluorocarbon (CFC)-12 analysis (26-34 years). The data suggest that the groundwater in wells in the study area originated up-gradient at distances of 140-230 m. Results of CFC analyses, along with seasonal variations in the δ¹⁸O and δD values of groundwater and the relationships between ²²²Rn concentrations and δ¹⁸O values and between ²²²Rn concentrations and δD values, indicate that groundwater recharge occurs in the summer rainy season and discharge occurs in the winter dry season. Additionally, a linear relationship between dissolved SiO₂ concentrations and groundwater ages indicates that natural mineralization is affected by the dilution of groundwater recharge in the rainy summer season.

• 한국작물학회지
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• 제42권4호
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• pp.466-472
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• 1997

Vegetable perilla, "Ipdlkkae 1"(Perilla frutescens var japonica Hara), was tested about the flowering and maturing responce in summer and winter. In summer season, it was researched about those responses according to the change of seeding date from May 15th to Oct. 15th at one month interval in the field. "Ipdlkkae 1" flowered Oct. 2nd under the day length of eleven hours and fourty-one minutes, compared with Sep. 6th (day length of twelve hours and fourty-three minutes) of "Yepsildlggae". And those responses showed that vegetable perilla was have to seeded before July 15th for two reason. The first is a unique response of perilla to day length. If perilla stay under short-day condition for some days, perilla will flower after four weeks. The second is a weather, especially frost and cold. In the test of latest seeding at Oct. 15th, the plants flowered more late than normal flowering period and they were not able to mature for frost of early winter. And this result showed that any other species, which has the characteristic of later flowering than that of "Ipdlkkae 1", could not able to mature in the field. In winter time, this species was tested about the same responses according to the change of short-day treatments. In the case of the test from May 1st (above fourteen hours day length), even if the test plants were stayed under short-day condition for more than 10 days, they were not able to mature, but flowerd. From the test of Apr. 15th, day length of thirteen hours, the plants were showed variable reaction to the short-day treatment. In this test, 11days for short-day treatment was a basic day to decide whether flowering was delayed or not. In the test from Apr. 1st, perilla seeds were able to harvest at least 5 days short-day treatment. In the final test from Mar. 15th, it had no need to take short-day treatment for harvesting of normal seeds, because the day length of that are twelve hours, which is an enough time to induce flowering and maturing, previously reported.

• 대기
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• 제18권3호
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• pp.237-248
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• 2008

A thermal index which considers metabolic heat generation of human body is proposed for operational forecasting. The new thermal index, Perceived Temperature (PT), is forecasted using Weather Research and Forecasting (WRF) mesoscale model and validated. Forecasted PT shows the characteristics of diurnal variation and topographic and latitudinal effect. Statistical skill scores such as correlation, bias, and RMSE are employed for objective verification of PT and input meteorological variables which are used for calculating PT. Verification result indicates that the accuracy of air temperature and wind forecast is higher in the initial forecast time, while relative humidity is improved as the forecast time increases. The forecasted PT during 2007 summer is lower than PT calculated by observation data. The predicted PT has a minimum Root-Mean-Square-Error (RMSE) of $7-8^{\circ}C$ at 9-18 hour forecast. Spatial distribution of PT shows that it is overestimated in western region, while PT in middle-eastern region is underestimated due to strong wind and low temperature forecast. Underestimation of wind speed and overestimation of relative humidity have caused higher PT than observation in southern region. The predicted PT from the mesoscale model gives appropriate information as a thermal index forecast. This study suggests that forecasted PT is applicable to the prediction of health warning based on the relationship between PT and mortality.

• Ocean and Polar Research
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• 제33권spc3호
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• pp.385-395
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• 2011

Time-series sediment traps were deployed at 1,000 m water depth of the northwestern subtropical Pacific from July 2009 to June 2010, with the aim of understanding temporal and spatial variations of sinking-particle fluxes. The opening and closing of the traps was synchronized at 18-day periods for 20 events. Total mass fluxes showed distinct seasonal variations with high values for the summer-fall seasons and relatively low values for winter-spring. This seasonal variation at two stations was characterized by a distinct difference in $CaCO_3$ fluxes between the two seasons. The enhanced $CaCO_3$ flux in the summer - fall seasons might be attributed to an increased planktonic foraminiferal flux. Total mass flux at FM10 station was nearly 50% higher than that at FM1 station. The difference in $CaCO_3$ fluxes between two stations contributed nearly 70% of the difference of total mass fluxes. The $CaCO_3$ flux was a major component controlling temporal and spatial variation of sinking - particle fluxes in the western subtropical Pacific Ocean.

• 대한환경공학회지
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• 제33권7호
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• pp.501-510
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• 2011

한강의 주요 14개 지류하천 유역의 수질오염원을 평가하고, 2007. 1~2009. 12의 하천 수질자료(14 data set)로 SPSS-17.0을 이용하여 하천별 수질 특성을 평가하였다. 시 공간변화에 대한 군집 분석을 실시한 결과 공간변화에 따라 4그룹으로 평가되었으며, 유역의 오염원 종류 및 밀도가 군집분류에 가장 큰 영향을 미치는 것으로 나타났다. 시간변화에 따라 여름에서 가을까지(7~10월)와 겨울에서 초여름까지(11~6월)의 2그룹으로 분류되어 강우와 기온 그리고 부영양화 현상이 군집화에 기여하는 것으로 평가되었다. 조사대상 하천의 수질오염 요인은 유기물질 영양염류 세균오염요인과 하천 내 물질대사요인으로(71~90%) 설명되었고, 계절에 따라 주요인(수질오염물질)은 변화하는 것으로 나타났다. 각 하천의 수질특성은 요인과 유역 오염원을 같이 평가하였을 때 유용한 결과를 얻을 수 있었다.

• 한국물환경학회지
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• 제25권5호
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• pp.742-749
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• 2009

To examine the characteristics of the nutrient release from the sediments in two reservoirs, Lake Paldang and Lake Cheungpyeung, we analyzed physical and chemical properties of the sediments and calculated the nutrient release rates from the sediments. The particle properties of sediments in Lake Paldang changed from silt to sand after summer rainy season, especially in the water area of the Kyeungan River where the water depth was shallow and the width of river was narrow. The sediments in Lake Cheungpyeung had higher contents of silt and clay than in Lake Paldang, and the particle size was not much different before and after rainfall. The release rates of nutrients in two lakes varied with the kind of nutrients and the season. The release rates of DTN and ${NH_4}^+-N$ in Lake Paldang were faster in spring than autumn. But the Lake Cheungpyeung showed similar values of release rates before and after summer rainy season. ${NO_3}^--N$ and phosphorous were not released from sediments or were absorbed into sediments all the time in two lakes. Compared with other lakes, the sediments of two lakes consisted of bigger particles and had a lower organic matters content than other lake-type reservoirs. Due to the short hydraulic retention time and no stratification throughout the year in Lake Paldang and Lake Cheungpyeung, the release rates of nutrients from sediment in these reservoirs were lower than other lakes and this seems to be a typical characteristic of river-type reservoirs.