• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.2
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• pp.244-250
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• 2019

We investigated the relationship between morphological characteristics and individual dry weight to develop a method for estimating the individual dry weight of sheet form macroalgae: Ulva australis, Ulva linza, Pachymeniopsis lanceolata, and Pyropia yezoensis. In Total, 319 thalli of various sizes were collected at six sites from February 2017 to December 2018. An interspecific allometric exponent of 0.28 was found for length-biomass allometry in four sheet form macroalgae, corresponding to a 1/4-power law for primary producers. The relationships between surface area and individual dry weight, as well as between individual fresh weight and individual dry weight, were found to fit significantly using linear regression equations. This explained 94-99 % of individual dry weight, indicating that surface area and individual fresh weight can be used to accurately estimate individual dry weight. We propose the use of this method when experimental processes do not allow individual dry weight to be measured directly, so researchers can save both time and expense.

• The KIPS Transactions:PartD
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• v.11D no.7 s.96
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• pp.1451-1458
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• 2004

Current software reliability growth models based on Gompertz growth curve are all logarithmic type. Software reliability growth models based on logarithmic type Gompertz growth curve has difficulties in parameter estimation. Therefore this paper proposes a software reliability growth model based on the logistic type Gompertz growth curie. Its usefulness is empirically verified by analyzing the failure data sets obtained from 13 different software projects. The parameters of model are estimated by linear regression through variable transformation or Virene's method. The proposed model is compared with respect to the average relative prediction error criterion. Experimental results show that the pro-posed model performs better the models based on the logarithmic type Gompertz growth curve.

• Journal of the East Asian Society of Dietary Life
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• v.11 no.6
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• pp.472-478
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• 2001

This study was conducted to investigate the change in volatile flavor components of persimmon leaves during growth. The flavor components of persimmon leaves were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry(GC/MS). The flavor compounds were collected by simultaneous steam distillation and extraction(SDE) method, and were separated and identified resulting in 126 components, including 23 alcohols, 18 aldehydes, 4 esters. 15 acids, 37 hydrocarbons, 14 ketones, 6 phenols. and 9 others in persimmon leaves. The most abundant components of persimmon leaf were alcohols including iinalool. cis-3-hexanal. 1-$\alpha$ -terpineol. 3.7.11.15-tetramethyl-2-hexadecen-1-ol and aldehydes including trans-2-hexanal. nonanal, 2-decenal and hydrocarbons including 1.1-dimethylethyl cyclohexane, 1-methyl-4-(2-methylpropyl) -benzene. During growth, many other components were formed and dissipated after the 20th of June.

• The Korean Journal of Malacology
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• v.28 no.4
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• pp.343-347
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• 2012

The growth rates of offspring of selected abalone (SA), Haliotis discus hannai, population for rapid growth were compared to those of offsping of the control abalone (CA) at bred under the same condition. The growth traits (shell length, shell breadth and total weight) of SA were significantly faster than those of CA at this experiment. At the 45th day and 90th day, the growth rates in shell length of SA were estimated 31.7% and 17.8% faster than those of CA, total weight of SA were estimated 43.7% and 25.6%, respectively. Moreover, the relative growth rate between shell length and total weight of SA showed significant differences higher than one in CA at 90th day. The results suggest a possibility of improving the growth rate of cultured abalone using selection techniques.

• Journal of Aquaculture
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• v.22 no.1
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• pp.92-99
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• 2009

Population dynamics and sexual maturity of Neomysis japonica (Ishikawa and Oshima, 1951) were investigated from a shrimp farm in Tae-an, Korea. N. japonica was collected monthly at the shrimp farm belonging to the Marine and Fisheries Research Institute, the Soonchunhyang University from October 2002 to September 2003. The proportion of female was higher than that of male. The mean carapace length of male (2.42 mm) was larger than that of female (2.31 mm). Brood size increased with increasing female body size. The size of N. japonica at 50% sexual maturity was approximately 4.4 mm. N. japonica females grew faster and reached larger size than males. The mortality rate (z) calculated by length-converted catch curves was $3.46\;yr^{-1}$. The annual recruitment pattern of N. japonica had two major peaks. Log-transformed total length was significantly related with log-transformed carapace length.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.217-227
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• 2019

The purpose of this study was to investigate the initial growth, burrowing depth, and relative growth of mud shrimps (Upogebia major and Austinogebia wuhsienweni), living in damaged high density tidal flat shellfish farms form 2008 in the Western coast of Korea. By August, young mud shrimps (Upogebia major), which had settled down on the tidal flats in early May, grew to more than 10 mm in carapace length (CL). At the end of the first year, their CL and total length (TL) increased to 14.21 mm and 42.28 mm, respectively. The inhabiting depth of the young mud shrimps (Upogebia major) increased rapidly up to about 6 months after stocking (5 cm in July, 12.5 cm in September, and 28 cm in November, respectively). The inhabiting depth of adult mud shrimps in their burrows was about 10-93 cm during the year. As results, the analysis of the relative growth between the carapace length (CL) - the total length (TL) and the CL - total wet weight (TWW), the total wet weight of mud shrimps at Boryeong Saho (inner part of the Cheonsu-bay) was estimated to be 1.2-4 g heavier than those of Boryeong Jugyo (Outer part of the Cheonsu-bay) tidal flat. The young mud shrimps primarily grew from April to October. It is therefore crucial to observe whether the settlement of young mud shrimps on tidal shellfish farms from May to June to minimize the damage of shellfish farms by newly stocked young mud shrimps. In addition, it is recommended that young mud shrimps grown in fisheries be harvested before they dig deep into the sediment until early December.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.2
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• pp.324-333
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• 1997

Porous alumina specimens with 80~92% relative densities were prepared from ultrasonic spray pyrolyzed alumina Powders by sintering at $1600^{\circ}$~ $1700^{\circ}C$. The exaggerated grain growth appeared to high sintering temperature and long soaking time. The microstructural development during sintering was investigated using image analysis. In the study of grain growth kinetics for sintering for spray prolyzed alumina powder, the activation energy for normal grain growth was 386.77 kJ/mol.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2002.04b
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• pp.13-13
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• 2002

분말사출성형(PIM, Powder Injection Molding) 기술은 금속, 초경 또는 세라믹 등과 같은 소결 가능한 분말을 유기결합체와 혼압하고 이를 기존의 사출성형법을 이용하여 일정한 형상으로 성형한 다음 결합제 제거정 공정을 거처 최종 고온 소결함으로써 3차원의 복잡한 형상의 부품을 후가공 없이 정밀하게 대량 생산 할 수 있는 신분말 성형 기술이다.기계 , 항공,전자정보,반도체,의료 등의 제반 분야에서 산업 및 생활기기들이 초소형화, 초정밀, 및 고기능호 되어 감에 따라 부품 또한 일반 공정에서 제조하기 힘든 크기로 초소형화 되고, 형상이 더욱 복잡화 되며 우수한 기계적 특성 또한 요구되고 있다. 세계 분말 사출성 ; 산업은 이러한 산업적 요구에 맞춰 급격히 발전함과 동싱에 시장 또한 급격히 성장되고 있다. 그러나 국내의 PIM 산업은 88년 기술이 도입된 이후 세계 PIM 산업의 성장 속도를 따라가지 못하고 있는 실정이다. 이번 발표에서 국내의 PIM 산업 현황을 조사하여 국내 시장 규모. 성장 속도, 주요 PIM업체의 소개할 예정이다. 그리고 국내 PIM 산업의 상대적인 저성장 요인을 분석하고 향후 국내 PIM 업계의 발전 방안을 제시할 예정이다. 예정이다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.10
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• pp.831-835
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• 2014

The relative concentration of surface and interfacial defects in hydrothermally grown ZnO nanostructures was investigated by a comparison of two samples having different growth temperatures via bias voltage sweep rate under laser illumination of 405 and 355 nm. The current of small ZnO nanostructures (growth temperature of $75^{\circ}C$) decreased when induced more slowly bias voltage sweep rate under the laser illumination. In contrast, the current of large ZnO nanostructures (growth temperature of $90^{\circ}C$) increased. This difference in currents indicates the relation of relative defects concentration between surface and interfacial defects of ZnO nanostructure. Our experimental approach has potential applicability in the analysis of influence on defects in ZnO devices.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.10a
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• pp.151-153
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• 2008