• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2006년도 하계학술발표대회 논문집
• /
• pp.1043-1048
• /
• 2006

This paper aimed to verify and develop lighting design data for offices in Korea. It focused on a Korean standard office value relative to lighting density and the evaluation of lighting energy and cooling load. When planning indoor lighting design, we generally utilize the lighting density value which is set $14W/m^2$ by the ASHRAE/IES standard office value. However, the value is not appropriate to apply in Korea where higher efficiency lamps are more popular than others. For calculation of a proper lighting density of Korea, we analysed distribution curves of luminous intensity(2-lamp fluorescent lighting fixture with Parabolic) and derived the new lighting density $12.64W/m^2$ as Korea standard office value. In the simulation using this value, it was shown that lighting energy and cooling load could be reduced.

• 국제초고층학회논문집
• /
• 제13권1호
• /
• pp.57-67
• /
• 2024

With the requirement of high quality and three-dimensional urban development, the public space areas city-center rail transit stations is expanded from the plots defined by the road network density to the plots defined by the three-dimensional public space density, covering the internal and external paths of the plots, which brings about the resilient pattern of plot utilization. This paper uses the isochronous three-dimensional influence realm model around the station areas to quantitatively analyze and compare the surrounding three-dimensional path density of public space, and initially proposes flexible use patterns of differently scaled plots under the multi-scale plots linkage, to effectively promote the overall accessibility of the station realm space.

• 한국수산과학회지
• /
• 제48권5호
• /
• pp.798-804
• /
• 2015

The distributions of demersal fish along the coast of the South Sea, Korea, were estimated from a hydroacoustic survey and bottom trawl catches in April of 2015. Acoustic data were collected at 38 kHz, and converted into the nautical area scattering coefficient (NASC, m²/n·mile²) for 0.1 n∙mile along eight transects during day and nighttime. Various demersal fish species were collected and the dominant species comprised no more than half of the catch. The estimated acoustic density of demersal fish compared well with the cumulative catch weight from bottom trawl catches in daytime, but showed a low correlation at nighttime. The NASC of pelagic fish determined for anchovy was correlated with water temperature. The combined hydroacoustic and trawl method can be used to understand the spatial/temporal structure and estimate the density of demersal fish in coastal areas.

• 한국수산과학회지
• /
• 제47권5호
• /
• pp.588-596
• /
• 2014

To examine the influences of water temperature and stocking density on feeding, growth and blind-side hypermelanosis of the starry flounder Platichthys stellatus, we performed an experiment with fry at two densities: 2 and 8 fish/L. The fry had a total length of $3.2{\pm}0.1cm$, body weight $0.6{\pm}0.1g$, and pigmented patches (pigmented ratio $2.6{\pm}0.4%$) on the blind side. Duplicate experiments were conducted in 93.7 L glass tanks for 120 days, from July to November. We determined daily food intake (DFI), food efficiency (FE), growth, survival rate, ratio of hypermelanic fish, and pigmented area rate on the blind side at 60-day intervals. The DFI was less than 50 mg/fish/day, and growth was delayed from July to September (water temperature [WT]> $20^{\circ}C$). After October, when WT < $20^{\circ}C$, the DFI increased significantly and the growth was accelerated, suggesting that the rearing temperature of starry flounder in artificial facilities should be < $20^{\circ}C$. While the FE, and survival did no differ between the two density groups, DFI and growth were significantly higher at 2 fish/L than at 8 fish/L. There was no difference in the pigmented area ratio between the two density groups. Although the hypermelanosis was not correlated with body size, the malpigmentation increased with growth. These results suggest that a high stocking density is not the main cause of blind-side hypermelanosis, although it can accelerate hypermelanosis in the starry flounder.

• Journal of Oral Medicine and Pain
• /
• 제45권4호
• /
• pp.83-88
• /
• 2020

Purpose: Growth differentiation factor 11 (GDF11) and myostatin (MSTN) are closely-related transforming growth factor β family members reported to play crucial roles in bone formation. We previously reported that, in contrast to MSTN, GDF11 promotes osteogenesis of vertebrae and limbs. GDF11 has been also reported as an important regulator in tooth development by inducing differentiation of pulp stem cells into odontoblasts for reparative dentin formation. The goal of this study was to investigate the differential roles of GDF11 and MSTN in dental and cranial bone formation. Methods: Micro-computed tomography analysis was performed on cranial bones, including frontal, parietal, and interparietal bones, and lower incisors of wild-type, Gdf11 knockout (Gdf11-/-), and Mstn knockout (Mstn-/-) mice. Tissue volume, thickness, and mineral density were evaluated for both cranial bone and lower incisors. Lower incisor lengths were also measured. Because Gdf11-/- mice die shortly after birth, analysis was performed on newborn (P0) mice. Results: Compared to those of Mstn-/- mice, cranial bone volume, thickness, and mineral density levels were all significantly diminished in Gdf11-/- mice. Tissue mineral density of Gdf11-/- mice were also significantly decreased compared to wild-type mice. Likewise, lower incisor length, tissue volume, thickness, and mineral density levels were all significantly reduced in Gdf11-/- mice compared to Mstn-/- mice. Incisor length was also significantly decreased in Gdf11-/- mice compared to wild-type mice. Mstn-/- mice exhibited mildly increased levels of tissue volume, thickness, and density in cranial bone and lower incisor compared to wild-type mice although statistically not significant. Conclusions: Our findings suggest that GDF11, unlike MSTN, endogenously promotes cranial bone and tooth development.

• 한국수산과학회지
• /
• 제31권6호
• /
• pp.869-874
• /
• 1998

사료종류에 따른 참전복의 적정 사육밀도를 조사하기 위해 평균 각장 8.41 mm의 치패를 $m^2$당 1430, 2860, 4290 및 5720마리로 설정하여 배합사료 및 미역을 실험구마다 3반복으로 15주간 공급하면서 사육 실험하였다. 전중, 패각 및 가식부의 성장은 사육밀도가 높아질수록 감소하는 경향을 보여 4290마리/$m^2$ 이상인 밀도구에서는 1430마리 /$m^2$ 밀도구와 유의차를 보였다(P<0.05). 또한 이러한 성장효과는 배합사료 공급구가 미역 공급구보다 밀도에 관계없이 양호한 성적을 보였으며, 동일 밀도구에서는 유의하게 (P<0.05) 배합사료 공급구가 높았다. 생존율도 성장과 비슷한 경향을 보였다. 실험 종료시 가식부의 일반성분의 변화는 사육밀도에는 영향을 받지 않았으나 사료종류에 따라 달라지는 경향을 보여 미역 공급구에 비해 배합사료 공급구의 수분과 단백질 함량은 낮고, 지질과 회분 함량은 높은 경향을 보였다 (P<0.05). 성장과 생존율 등을 고려하여 보면 각장 9$\~$17mm일 때 참전복의 적정 사육밀도는 사료의 종류에 관계없이 1 $m^2$당 2860마리 이하가 적절하다고 여겨진다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권9호
• /
• pp.4661-4664
• /
• 2012

Mammographic breast density is a known risk factor for breast cancer. To conduct a survey to estimate the distribution of mammographic breast density in Korean women, appropriate sampling strategies for representative and efficient sampling design were evaluated through simulation. Using the target population from the National Cancer Screening Programme (NCSP) for breast cancer in 2009, we verified the distribution estimate by repeating the simulation 1,000 times using stratified random sampling to investigate the distribution of breast density of 1,340,362 women. According to the simulation results, using a sampling design stratifying the nation into three groups (metropolitan, urban, and rural), with a total sample size of 4,000, we estimated the distribution of breast density in Korean women at a level of 0.01% tolerance. Based on the results of our study, a nationwide survey for estimating the distribution of mammographic breast density among Korean women can be conducted efficiently.

• The Journal of the Acoustical Society of Korea
• /
• 제22권2E호
• /
• pp.69-77
• /
• 2003

Correlations between acoustic properties and bone density have been investigated in bovine cancellous bone. Speed of sound (SOS), broadband ultrasonic attenuation (BUA), and broadband ultrasonic reflection (BUR) were measured in 10 defatted bovine cancellous bone specimens in vitro. SOS showed a significant correlation with the apparent density of the bone. A comparable correlation was observed between BUA and the apparent density. BUR was rather highly correlated with the apparent density. It was shown that BUR had a weak correlation with BUA and a significant correlation with SOS. This indicates that the parameter BUR can provide important information that may not be contained in BUA and SOS and, therefore, can be useful as an alternative diagnostic parameter of osteoporosis. As expected, a linear combination of all three ultrasonic parameters in a multiple regression model resulted in a significant improvement in predicting the apparent bone density.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2006년도 춘계 학술발표회 논문집
• /
• pp.1358-1366
• /
• 2006

In order to study the effects of shell contents on the liquefaction resistance of the shelly sand, NGI cyclic simple shear tests were performed for the shelly sands with shell contents of 0%, 5%, 10%, 20% and 30% under the effective vertical stress of 50kPa, 100kPa and 150kPa for 40% and 55% of relative density, respectively. Cyclic simple shear test results showed that for the low effective vertical stress, liquefaction resistance increased rapidly with the increase of shell contents in both 40% and 55% relative density. On the other hand, for the high effective vertical stress, the liquefaction resistance increased slightly in 40% relative density whereas the resistance was almost same in 55% relative density. Liquefaction resistance decreased with increasing effective vertical stress for both 40% and 55% relative density. In the same effective vertical stress and shell contents, liquefaction resistance increased with the increase of relative density of sands.

• 신재생에너지
• /
• 제16권4호
• /
• pp.1-8
• /
• 2020

The possibility of conversion to the RC-MAT propulsion system (gasoline engine → electric motor) was studied. However, as commercial battery capacities are low. it is not possible to change the propulsion system. Nevertheless, development of nex-generation batteries is necessary for high capacity and high energy density. Although Li/S batteries are theoretically suitable as new generation batteries, these batteries are not composed of only Li and S. Hence, ensuring high energy density can be difficult. Moreover, electrolytes are important components in the study of energy density; hence, the battery by Li2S8 Molarity was sorted. There are no studied on its various electrode components. In this study, a Li/S battery was fabricated using an assorted 3D sulfur electrode of high energy density and its electrochemical properties were studied. The Li/S battery has a high energy density of 468 Wh/kg at 1.28 M Li2S8 (A805-1.28). Its capacity rapidly decreased after 1 cycle with more than 1 M Li2S8.