• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
• /
• pp.534-534
• /
• 2006

• 대한지리학회지
• /
• 제16권
• /
• pp.1-9
• /
• 1977

• Journal of Chest Surgery
• /
• 제11권4호
• /
• pp.416-421
• /
• 1978

• 한국건축시공학회지
• /
• 제6권2호
• /
• pp.73-79
• /
• 2006

The purpose of this study is to enhance the development of construction waste-recycling technologies and its economical efficiency by developing environment-friendly tetrapod, precast concrete, where recycled aggregate is used in order to promote recycling of waste concrete. The results of concrete mechanic characteristics experiments by the circulation coarse aggregate-replacement ratio are as the following. The circulation aggregate is lower and higher than natural aggregate in specific gravity and absorption ratio, respectively so that in case of mix proportioning, unit volume increases, while unit aggregate amount decreases. From the result, sufficient experiments of physical characteristics of circulation aggregate are required to get proper mix proportioning. When circulation aggregate-replacement ratio increases, compressive strength tends to decrease comprehensively, but 50% of replacement ratio is good enough to use. When circulation coarse aggregate's replacement ratio is 0%, drying shrinkage, which causes cracks in concrete and deteriorates durability, shows the minimum length change and the higher the ratio, the larger the length change. Thus. when using circulation coarse aggregate, drying shrinkage should be fairly examined. In freezing-and-thawing resistance, weight loss tends to comprehensively increase its loss at the circulation aggregate-mixed site. And the examination of surface aggregate-omission ratio is further needed and dynamic elastic modulus and durability factor(DF) require more study as well. In order to use circulation aggregate to tetrapod, a clear standard for strength should be first prepared and at the same time, more study about durability is needed.

• 한국해안·해양공학회논문집
• /
• 제22권4호
• /
• pp.215-223
• /
• 2010

진주만에서 계절별 해수순환구조의 특성을 해석하기 위해 진주만의 서쪽인 노량수로와 동쪽인 대방수로에서 해수유동을 2005년부터 2008년까지 장기간 관측하였다. 진주만의 해수유동은 주로 노량수로와 대방수로를 통한 해수교환에 의해 지배된다. 동계 노량수로의 표층에서 조류는 광양만에서 동쪽인 진주만으로 유입하는 흐름이 발생하고, 저층에서는 진주만에서 서쪽인 광양만으로 유출하는 흐름이 발생하고 있다. 하계 노량수로의 표층에서 조류는 진주만에서 서쪽인 광양만으로 유출하는 흐름이 발생하고 있다. 즉, 노량수로에서 해수순환은 전형적인 열염분순환 형태를 보여주고 있다. 춘계 동-대방수로의 표층에서 조류는 진주만에서 외해로 유출하는 중력순환류가 발생하고 있다. 그러나, 하계 서-대방수로에서는 전층에 걸쳐 진주만내로 유입하는 흐름 양상을 보여주고 있다. 유속의 크기는 서-대방수로에서 유속이 동-대방수로에서 유속보다 약 50~70 cm/sec 정도 크게 나타났다. 노량수로와 대방수로에서 계절별 해수순환 패턴을 보다 정확하게 해석하기 위해서는 현장관측과 3차원 수치모형실험에 관한 상세한 연구가 추가적으로 수행되어야 할 것으로 사료된다.

• 한국치위생학회지
• /
• 제8권1호
• /
• pp.13-22
• /
• 2008

This study compared tooth's remineralization using enamel surface artificially demineralized with 0.1M lactate and HCL solution using Vicker's Hardness Number(VHN) to compare CPP-ACP and remineralization of nano-sized Carbonate Apatite's initial caries. Using pH circulation models divided into 0% nano-CA, 5% nano-CA, 10% nano-CA, 10% CPP-ACP and D.W. they were treated for 5 minutes, three times a day for 14 days to get the following results. 1. There were no significant differences among the initial surface hardness of samples demineralized surface of front tooth in 5 groups. and all 5 groups' surface hardness reduced significantly after demineralization of enamel. 2. When inquiring into hardness changes through pH circulation model, the highest hardness change was in 5% nano-CA group. Also. 10% nano-CA and 10% CPP-ACP groups increased significantly. but there was no significant difference statistically. In generalizing the above experiment results, nano-sized Carbonate Apatite showed remineralization, and compared to 10% CPP-ACP group, 5% nano-CA had remineralization to artificial caries. thus implies that when we develop method to contact with tooth of nano-CA in the future, it is expected to gain synergy effect on function of saliva, a natural remineralization material.

• 한국해양학회지
• /
• 제24권2호
• /
• pp.96-108
• /
• 1989

동해의 해수 순환에 영향을 주는 요인들 가운데 대기와의 열 염교환과 바람에 대한 순환계의 반응을 Semtner(1974)의 3차원 수치모델을 이용하여 규명하였다. 동해와 북태평양을 연결하는 해협을 막아 유출입이 배제된 상태에서 구해진 한국 동안을 따라 북상하는 흐름과 동해 북동부의 반시계방향 순환 등의 표층 해수 순환은 Uda(1934) 및 Naganuma(1972)에 의한 해류모식도와 유사하다. 또한 100-200m 층에서 Kim and Kim(1983)이 지적한 북한한류와 비슷한 남향류가 한국 동안을 따라 나타났고, 동해 고유냉수가 형성되는 것과 유사한 형태로 동해 북동부 해역에서 상대적으로 고염인 해수의 침강현상이 나타났다.

• 대한의용생체공학회:의공학회지
• /
• 제40권6호
• /
• pp.235-241
• /
• 2019

The purpose of this study was to investigate the effect of the body temperature peripheral circulation with vibration shoes in healthy 10 adults. The magnetic vibration device with non-electric power was mounted in the midsole of the vibration shoes. The experiment was divided into two groups: vibration shoes and no vibration shoes. Subjects were randomly selected and measured body surface temperature by digital infrared thermal imaging (DITI) and non-invasive capillaries change by nailfold microscope (NFM). After walking in a treadmill for 15 minutes at 4.0 km/h speed wearing normal shoes or vibration shoes, DITI and NFM were measured. The walking with vibration shoes showed the body surface temperature shift from the proximal to the distal. In addition, the diameter of the nailfold capillary in the vibration shoes group was thicker and clearer due to the increased blood flow than that of the no vibration shoes group. The vibration shoes are easy to apply to anyone who can walk because it can give vibration stimulation by walking without additional time, cost, and effort in daily life. Further studies are needed to explain the physiological effects of vibration frequency and intensity on the long-term perspective of target subjects resulting from vascular dysfunction.

• 한국환경과학회지
• /
• 제33권3호
• /
• pp.227-234
• /
• 2024

We investigated the change in land-use alteration in a 45 km × 45 km area around the Upo wetlands in 1920s(before the Japanese occupation period), 1950s(immediately Korean independence) and the period 1970s to 2000s. These data can guide in understanding surface environmental changes in the lower Nakdong River from the early 20^th century to the present. The influence of the long-term decreasing trend of the wetland area at the Upo Swamp was evaluated using a high-resolution local circulation model. The cooling effect of the wetlands on surface air during the daytime in summer(e.g, early August) was approximately 2℃ greater in the 1920s than in the 2000s, which is attributed to wider water areas in the 1920s. Additionally, long-term changes in land use have caused changes in the convergence zone of local circulation wind.

• 한국대기환경학회지
• /
• 제25권4호
• /
• pp.304-315
• /
• 2009

Numerical simulations were carried out to understand the effect of Sea Surface Temperature (SST) spatial distribution on regional circulation. A three-dimensional non-hydrostatic atmospheric model RAMS, version 6.0, was applied to examine the impact of SST forcing on regional circulation. New Generation Sea Surface Temperature (NGSST) data were implemented to RAMS to compare the results of modeling with default SST data. Several numerical experiments have been undertaken to evaluate the effect of SST for initialization. First was the case with NGSST data (Case NG), second was the case with RAMS monthly data (Case RM) and third was the case with seasonally averaged RAMS monthly data (Case RS). Case NG showed accurate spatial distributions of SST but, the results of RM and RS were $3{\sim}4^{\circ}C$ lower than buoy observation data. By analyzing practical sea surface conditions, large difference in horizontal temperature and wind field for each run were revealed. Case RM and Case RS showed similar horizontal and vertical distributions of temperature and wind field but, Case NG estimated the intensity of sea breeze weakly and land breeze strongly. These differences were due to the difference of the temperature gradient caused by different spatial distributions of SST. Diurnal variations of temperature and wind speed for Case NG indicated great agreement with the observation data and statistics such as root mean squared error, index of agreement, regression were also better than Case RM and Case RS.