• Journal of Animal Science and Technology
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• v.50 no.5
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• pp.581-590
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• 2008

Growth curves for ultrasonic carcass traits such as longissimus muscle area, backfat thickness and marbling score as well as chest girth which was simultaneously measured when carcass traits were investigated using ultrasound measuring technique were estimated to identify growth patterns and to adjust maturing effects in order to evaluating genetic merits on cows in farming basis. 27,410 records from 22,451 cows on which of 15~90 month of age were investigated from the national wide of Korea using by ultrasonic scanning techniques by the skilled persons from 2002 to 2007. Van Bertalanffy growth function was applied for estimating growth curves on these traits. Carcass traits and chest girth would be linearly increased by body condition score. It might be used for multiplicative correction factors for pre- adjustment on the body condition scores. Growth pattern on chest girth would be quickly reached to mature size and stable on after reached to asymptotic mature size. Longissimus muscle area would also be reached to mature size but little smoother than chest girth. Otherwise, growth curve on backfat thickness would be steadily increasing up to 7 years of age. It also showed large individual difference by way of mean square error. Marbling score would be steadily increased but sharper than those on backfat thickness. It would be reached to mature size up at 5 years of age. Those growth curves would be used for correcting function on age at investigating on genetic evaluation system.

• Journal of the Korean Vacuum Society
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• v.3 no.1
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• pp.33-38
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• 1994

-Hot-wall epitaxy 방법에 의하여 GaAs(100) 기판위에 CdTe(100)박막을 성장하였다. 박막을 성 장하는 동안 기판의 온도는 28$0^{\circ}C$ 증발원의 온도는 $430^{\circ}C$로 유지하였고 성장률은 $2mu$m/h이었다. 박막의 두께가 증가함에 따라 격자상수와 2결정 X-선 요동곡선의 반폭치가 감소하였다. CdTe (100) 박막의 광 전류 스펙트럼으로부터 에너지 띠간격의 광전류 봉우리는 가전자대 8 에 있는 전자가 광흡수에 의해 전도대 6 전이한 것이며 에너지 띠간격의 온도의존성을 구한 결과 온도계수 a=-2.3~-3.5 x 10-4 ev/k.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.12 no.sup1
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• pp.1-5
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• 2009

2007 Korean National Growth Charts were published by The Korean Pediatric Society and Korea Centers for Disease Control and Prevention in October, 2007. These Growth Charts are composed of Growth Curves and Tables, which are based on the principles such as pooling data of the different generations and application of LMS method. In this review, several tips of application using these new charts are summarized with points of view both in clinical and research fields.

• Journal of the Korean Society for Precision Engineering
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• v.6 no.3
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• pp.78-89
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• 1989

Applicability of tearing modulus based on J-integral proposed by Paris et al is investigated using compact tension specimens of strutural alloy steel (SCM4). Both general fracture test and instability fracture test are performed. The applied tearing modulus, ( $T_{j}$)app estimated from the real load vs. crack growth curve measured from experiments are compared with that estimated from the limit load vs. crack growth curve. The results are : (1) the $T_{j}$parameter could be applied to predict crack growth instability : (2) The use of ( $T_{j}$)app estimated from the load vs. crack growth curve, proposed in this study could be well predicted crack growth instability instead of that estimated form the limit load vs. crack growth curve.e.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.3
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• pp.29-36
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• 1991

This experimental research evaluated the length of crack extension with the measured compliances as the mutual comparison factors instead of the method proposed in ASTM E561-80. And this research measured the R-curves with the application to the concept of the strain energy release rate that was formulated from the inelastic energy absorbed during the crack growth. With the interpretation of R-curves, this research obtained the starting point of the unstable crack growth, and compared the values of critical fracture toughness with each other, and then examined the effects of variations of the maximum size of coarse aggregate and the thickness of specimen on the values of the critical fracture toughness.

• Journal of Biomedical Engineering Research
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• v.22 no.2
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• pp.127-132
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• 2001

의료 영상에서 관심 있는 부위를 3차원으로 재구성하여 보는 것은, 정확한 진단을 위해서 매우 중요하다. 이러한 3차원 재구성을 위해서는 관심 있는 영역의 분할이 필수적인 선행작업이다. 본 논문에서는 관도계 기관의 분할을 위해서 슬라이스 영상의 정보를 이용한 3차원 영역 성장법을 제안한다. 제안된 방법은 2차원 슬라이스 영상에서 영역 성장법에 의해 영역을 확장시키고, 그 이웃한 슬라이스들에 씨앗점을 전달하여 재귀적으로 3차원 체적을 확장하여 영상을 분할한다. 이때, 이웃한 슬라이스간의 영역의 크기의 제약을 이용하여 새나감을 방지한다. 제안된 방법을 기관지의 분할에 적용한 결과, 새나감 없이 뾰족한 가지들까지도 성공적으로 분할했으며, 튜브의 중심 축이 고차원 곡선인 경우에도 성공적으로 분할했다.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.158-164
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• 2002

본 연구에서는 탄소나노튜브를 직류 바이어스가 인가된 유도결합형 플라즈마 열선 화학기상증착 장치를 이용하여 58$0^{\circ}C$ 이하의 저온에서 유리기판의 변형 없이 수직 배향 시켰다. 탄소나노튜브의 성장을 위해 강화유리기판 위에 전도층으로 Cr을 증착하였고, 그 위에 촉매 층으로 Ni을 순차적으로 RF magnetron cputtering 장치를 이용하여 증착 시켰다. 성장 시 탄소나노튜브의 저온에서의 좋은 특성을 위해 높은 온도에서의 열분해를 목적으로 텅스텐 필라멘트를 이용하였으며, 수직 배향 시키기 위해서 직류 바이어스를 이용하였다. 성장된 탄소나노튜브는 수직적으로 잘 배향 되었으며, 저온에서 좋은 특성을 보였다. 탄소나노튜브의 특성화에는 SEM, TEM을 관찰하였으며, Raman spectroscopy를 이용하여 흑연화도를 측정하였고, 전계방츨 특성은 전류 전압 특성곡선과 Fowler-Nordheim plots를 이용하였다.

• Clean Technology
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• v.29 no.2
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• pp.135-144
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• 2023

Pseudomonas aeruginosa and Staphylococcus aureus are the two most frequently encountered pathogens responsible for chronic wound infections, often coexisting in such cases. These infections exhibit heightened virulence compared to single infections, leading to unfavorable patient outcomes. The interaction among microorganisms within polymicrobial infections has been shown to exacerbate disease progression. Polymicrobial infections, prevalent in various contexts such as the respiratory tract, wounds, and diabetic foot, typically involve diverse microorganisms, with Pseudomonas aeruginosa and Staphylococcus aureus being the most commonly identified pathogens. This study aimed to compare the growth patterns of bacteria under a concentration gradient of toxic chemicals, focusing on a Gram-negative strain of Pseudomonas aeruginosa and a Gram-positive strain of Staphylococcus aureus. The minimum inhibitory concentration (MIC), which signifies the concentration at which bacterial growth is inhibited, was determined by performing broth microdilution and assessing the bacteria's growth curves. The growth curves of both Pseudomonas aeruginosa and Staphylococcus aureus were confirmed, and the exponential growth phases were applied to calculate the doubling times of bacteria. The MIC value for each toxic chemical was determined through broth microdilution. These results allowed for the identification of disparities in growth rates between Gram-positive and Gram-negative bacteria, as well as differences in resistance to individual toxic substances. We expect that this approach has a strong potential for further development towards the innovative treatment of bacteria-associated infections.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.139-140
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• 2015

주석(Sn)은 뛰어난 유연성을 나타내기 때문에 접촉저항을 감소시킬 목적으로 전자부품과 전자기기의 도선과 단자를 피복하는데 사용된다. 하지만 특정한 조건에서 시간경과와 함께 위스커라는 침상결정이 발생하여 회로 단락을 초래하는 것이 문제이다. 위스커는 직선형, 굴곡형, 곡선형의 형태로 성장하며 직경은 $1{\mu}m$, 길이는 수백 ${\mu}m$에서부터 수 mm에 이른다. 발생 초기단계에서 성장이 정지된 작은 덩어리도 위스커와 함께 관찰된다. 주석도금 피막에서 발생하는 위스커는 1940년대 미국의 전화교환기 단락원인으로 널리 알려지게 되었다. 이러한 위스커를 억제하는 방법으로 주석-납 도금이 개발되었다. 주석-납 도금피막에서는 작은 덩어리가 다수 발생하는 반면에 위스커는 발생하지 않는다. 하지만 2006년 7월에 시행된 RoHS(Restriction of the use of certain Hazardous Substances) 지령에서 수은, 카드뮴, 6가 크롬 및 납은 유해물질로 지정되어 사용이 엄격히 규제되고 있다. 주석 도금피막의 위스커가 발생하고, 성장하는 원인으로 도금피막 내부의 압축응력과 전위, 산화피막, 도금피막-기판계면에서 발생하는 금속간화합물 주변의 변형을 들 수 있다. 본고에서는 도금하여 얻은 주석피막 표면에 형성된 위스커를 중심으로 증착피막과 주석도금 피막을 용융 응고하여 형성된 합금의 경시변화를 비교하고, 작은 덩어리와 위스커의 발생 및 성장 기구에 관하여 기술하였다.

• Environmental and Resource Economics Review
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• v.12 no.3
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• pp.515-529
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• 2003

This theoretical model makes three contributions to the study on economic growth and environment. First, emissions are generated during final goods production and technology accumulation. Second, this paper assumes that pollution is directly increasing with increase in final goods output or in consumption. Third, we use reproducible factors associated with labor and capital input in production function and assume constant return to scale in reproducible factors. From growth rate condition we derived, increases in reproducible factors, increases in productivity of either the abatment or technology sector, and decrease in social discount rate would increase the sustainable growth rate. In empirical test, the environmental degradation did not effect the economic growth rate though other factors satisfied the growth rate condition equation. However, through the reinterpretation of this result, we found indirectly the fact of that an inverted U relationship between air pollution and economic growth rate would exist in 20 OECD countries using a panel data for the period of 1986~1995.