• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.583-588
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• 2002

Young Seriola quinqueradiata associated with drifting seaweeds weye investigated monthly between April 1998 and March 1999 in the coastal area of Tongyeong, Korea, The most abundant types of seaweed were in the genus Sargassum, including S. horneri, S. miyabei and S. thunbergii. The size of seaweed patches varied by season: patches larger than 4 m in diameter were found in May, whereas patches smaller than 0.5 m in diameter were abundant in August and September. Young Serioia quinqueradiata ranged from 11.9 to 135.4 mm in total length were collected from May to July at the study area. The striped bands on the bodies of young Seriola quinqueradiata were developed at 10.0$\~$15.0 mm in total length and increased up to 12 bands with growth, These bands were gradually disappeared at 130.0$\~$150.0 mm in total length. There was no significant relationship between the number of Seriola quinqueradiata collected and the weights of the seaweed patches ($r^2=0.04,\;p<0.05$).

• Korean Journal of Poultry Science
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• v.20 no.4
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• pp.203-208
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• 1993

The objective of this study was to investigate the correlation among the measurements of the body weight and shank length at the age of 0, 4, 8, 12, 16 and 20 wk, and to investigate the regression of the final body weight at the age of 20 wk in selection on the body weight and shank length before 12 wk of age. From the simple correlation analysis, the range of correlation coefficients between body weight and shank length at the same age were 0.50~0.83 from females, and 0.57~0.85 from males over all wk of age(P＜0.01). Correlation coefficient between the body weights at hatch and 20 wk of age was 0.44(P＜0.01), but it was not significant(P＞0.05) between the shank length at hatch and body weight at 20 wk of age. The favorable regression models for the estimation of the body weight at the age of 20 wk from both body weight and shank length before 12 wk of age were the models with the independent variables of measurements at hatch and 12 wk of age($R^2$＝0.96), with the measurements at 8 and 12 wk of age($R^2$＝0.96), and with the measurements at 0, 8 and 12 wk of age ($R^2$＝0.96).

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.333-338
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• 1987

In order to establish the biological treatment system which can be used for treatment of waste aster from acetaldehyde plant, it was investigated optimum nutrient requirements and growth conditions by mixed culture of Micrococcus roseus AW-6, Micrococcus luteus AW-22, Microbacterium lacticum AW-38 and Microbacterium laevaniformans AW-41 as well as the effect of coagulants and neutralization reagents. Also, it was carried out the continuous culture as well as batch culture to treat the waste water by mixed culture of these strains. The COD removal rate was reached to maximum state for 96hrs culture at pH7.0 and $30^{\circ}C$ NaOH as the neutralization reagents was the most effective, but the coagulants had no effect on the COD remonal rate and the optimum dilution times for treatment were 10 fold. The COD removal rate was also increased by supplimenting 200 ppm $NH_{2}NO_{3}$, 50 ppm $KH_{2}PO_{4}$, 15 ppm $CaCl_{2}$ and 1 ppm $MgSO_{4} \cdot 7H_{2}O $ as additional nutrients. The removal rate coefficient $K_{1}$ on the batch culture was $4.5\times 10^{-6}$, and the detention time for BOD removal rate of 85% was approximately 45hrs. The COD of waste water was reduced to 15% of its initial value by the continuous culture. The COD and BOD of the effluents were to be about 60 ppm and 40 ppm, respectively, and final pH was 7.0.

• Tunnel and Underground Space
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• v.22 no.4
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• pp.276-283
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• 2012

Changes in rock properties due to freezing and thawing cycles ranging from $-20^{\circ}C$ to $10^{\circ}C$ were checked for the typical Korean rocks: granite (weathered), limestone, sandstone, tuff, shale and basalt. The porosity, seismic velocity, shore hardness and specific gravity were measured every 10 cycles for each type of rock up to 40 cycles. The specific gravity was rarely changed. Granite (w), shale and basalt decreased gradually in their shore hardness and seismic velocity values, these values for limestone, sandstone and tuff changed only a very little. The porosity increased in the granite (w), shale and basalt, whereas in the others it did not change. Due to the low tensile strength with high porosity, granite (w), shale and basalt were susceptible to the F-T cycles. A linear regression equation was calculated based on the experiment results according to properties and types of rock. The relationship between the freeze-thaw sensitivity (=initial porosity/initial tensile strength) and the coefficients of the regression equation was examined. With additional experimental data, the coefficients of the regression equation can be estimated using the F-T sensitivity. This makes it possible to predict the properties of rock as affected by freeze-thaw weathering by only measuring the initial properties without knowledge of the regression equation coefficients for each type of rock.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.412-418
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• 2007

The dynamics of Zacco platypus population of upstream and downstream in the lake Hoengseong, Korea were investigated from April to October 2005. Length-weight relationship, condition factor (K) and relative condition factor $(K_n)$ of Z. platypus were compared by the study stations. The equations based on length-weight relationship in the lake Hoengseong were $Log(T_w)=-2.2s+3.18{\cdot}Log(T_L)\;(r^2=0.99)$. The result in comparison of variations of Z. platypus populations, in lake was more remain to better than in upstream and downstream them. Also the b value, assessed by Length-weight relationship in lake was 3.36, in upstream and downstream were 3.09, 3.15, respectively indicating the fish in lake better than stream. The slopes of population condition controlled by K factor also showed positive relationship. It was higher in lake environment than in stream sample, reflecting that population of Z. platypus distributed in lake Hoengseong was favorable and stable condition. The lake environment seems to be providing more favorable condition for Z. platypus population.

• Proceedings of the SCSK Conference
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• 1996.07a
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• pp.33-51
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• 1996

화장품의 변질요인은 크게 물리적 또는 화학적 변화에 의한 요인과 미생물오염으로 인한 각종 문제점으로 대별될 수 있다. 이 중에서 미생물 오염문제는 제품의 상품가치에 미치는 영향 뿐만 아니라 지속적인 사용에 의한 피부의 위생적 측면때문에 그 중요성에 대한 인식이 높아지고 있다. 따라서, 제품개발시는 화장품 처방중의 영양성분의 배합, pH, 유화형태, 방부제의 혼합, 분배계수 및 그 안정성을 고려하여야 함은 물론이고 처방중의 모든 원료의 각각에 대한 항균능 및 피부자극여부를 사전에 미리 조사하여 각 제품별로 적당한 방부체계를 선택하는 것은 매우 중요한일이다. 독성실험방법에 있어서 in vivo 실험에 대체할 수 있는 새로운 in vitro 실험방법 수립 즉, 동물실험을 하지 않고 in vitro 실험결과로부터 in vivo 결과를 예측할 수 있도록 새로운 in vitro 실험체계의 가능성을 실험하였다. 4종의 cell line중 transformed mouse fibroblast L929가 본 실험에서 사용하기에 배양상의 용이성과 안정성, 재현성의 관점에서 가장 알맞은 cell line이었다. transformed mouse fibroblast L929를 사용한 NR$_{50}$ assay와 Draize score간의 regression coefficient ${\gamma}$값은 0.91이었다. 혈청은 시험물질의 세포에 대한 민감성에 영향을 주었다. 따라서, modified serum-free method를 이용함으로써 regression coefficient가 증가된 즉, 상관성 및 재현성이 높은 결과를 얻을 수 있었다. 이러한 기술은 독성실험에 실험동물을 사용하지 않고 in vivo test에 대체 할 수 있고, 또한 화학물질에 대한 prescreening으로 이용할 수 있을 것으로 판단된다.원과 섭식장소, 수중생물의 경우는 특히 수온, 수량 영양원등이다.(중략). 본 연구의 접근방법으로는 ASRS의 개념적인 Reference Model을 수립하고 이 Reference Model에 대한 Formal Model로 DEVS(Discrete Event System Specification)을 이용하여 시스템을 Modeling하였다. 이의 Computer Simulation을 위하여 DEVS형식론 환경에서의 Simulation Language인 DEVSim ++ⓒ를 이용하여 시스템을 구현하였다.. 실형 결과로는 먼저 선형 상미분방정식의 예로 mass-damper-spring system, 비선형 상미분방정식의 예로는 van der Pol 방정식, 연립 상미분방정식의 예로는 mixing tank problem 등을 보였으며, 그의 공학에서 일어나는 여러 가지 문제들도 다루었다.화물에 대한 방어력이 증가되어 나타난 결과로 여겨지며, 또한 혈청중의 ALT, ALP 및 LDH활성을 유의성있게 감소시키므로서 감잎 phenolic compounds가 에탄올에 의한 간세포 손상에 대한 해독 및 보호작용이 있는 것으로 사료된다.반적으로 홍삼 제조시 내공의 발생은 제조공정에서 나타나는 경우가 많으며, 내백의 경우는 홍삼으로 가공되면서 발생하는 경우가 있고, 인삼이 성장될 때 부분적인 영양상태의 불충분이나 기후 등에 따른 영향을 받을 수 있기 때문에 앞으로 이에 대한 많은 연구가 이루어져야할 것으로 판단된다.태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elements)로 가정한다. 즉, [+wh] 의미의 겹의문사는 동일한 구성요 소를 지닌 병렬적 합성어([$[W1]_{XO-}$ $[W1]_{XO}$ ]

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.6
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• pp.15-25
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• 2018

As jobless growth became the new norm and the average life expectancy continues to increase, it is difficult to find quality jobs regardless of gender. In this situation, entrepreneurs who can take charge of creating quality jobs have begun to gain attention from governments. As a result, many startup support programs have been introduced and operated. In Korea, various government-sponsored startup support programs have been in operation since the late 2000s, and the number of startups has increased since. However, there are many cases where they are not able to maintain their business for a long time because such programs often lack expertise and experience. Mentoring programs for startup founders is becoming an attractive solution to these problems. However, when we look at the responses of entrepreneurs, they found the mentoring program beneficial only when it was well planned and operated. Otherwise, they found the program unhelpful. Although there are many startup mentoring programs in various fields, there is little research on whether customized mentoring that matches the characteristics of startups and entrepreneurs are effective. In this study, we study the effects of startup mentoring on mentoring satisfaction. Our model also intends to identify the moderating effects of entrepreneurs' characteristics and provide guidance to future startup mentoring.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.360-375
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• 2019

This paper tries to study the ecosystem after constructing the network of the continuing transactions associated with distribution industry with the data of more than 50 thousands firms provided by the Korean enterprise data (KED) for 2015. After applying the clustering method, one of social network analysis tools, we find the firms in the network grouped into 732 clusters occupying about 80% of whole distribution industry sales in KED data. The firms in a cluster have most of their transactions with other firms in the cluster. But the clusters have smaller firm numbers in the cluster and sales portion of the biggest firms in the industry than the case of the manufacturing industry. The Input-output analysis for the biggest distribution firms show that the small and medium size enterprise(SME)s have very high sale dependency on a main firm in some clusters. This fact implies more efficient fair transaction policies within the clusters. And small number of big distribution firms have very high rear production linkage effects on SMEs or on the 10th or 31th group with high portion of SME employment. They should be considered important in the SME growth and employment policies.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.1
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• pp.10-20
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• 2019

Individual dental age is used as an index of chronological age estimation and is an important indicator of the child's growth stage. Dental age does change greatly over time, but it changes constantly. And updating information about this change is important. The purpose of this study was to provide information about tooth eruption stage using diagnostic model analysis and to investigate tooth eruption sequence and estimate chronological age based on this information. Tooth eruption stages were measured on a diagnostic model from 488 patients in 5 - 13 year old children. Based on the information on eruption stage, eruption sequence in maxilla was first permanent molar, central incisor, lateral incisor, first premolar, canine, second premolar and second permanent molar. Eruption sequence in mandible was first permanent molar, central incisor, lateral incisor, canine, first premolar, second premolar and second permanent molar. There were significant differences between males and females in the eruption stage of canine, first and second premolar, and second molar at several ages. The chronological age of male and female was estimated by the coefficient of determination of 0.816, 0.826 respectively.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.68-80
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• 2021

This study aimed to present the current status of exotic fish species, invasive species, and dominant species inhabiting the Cheonggyecheon stream. We conducted three samplings from April to October 2019. A total of 2,045 individuals from 27 species belonging to nine fish families were collected. There were five Korean endemic species (18.5%) including Coreoleuciscus splendidus, Sarcocheilichthys nigripinnis morii, Squalidus gracilis majimae, Zacco koreanus, and Odontobutis interrupta in the Cheonggyecheon stream. The dominant species was Zacco platypus (62.4%) and the subdominant species was Z. koreanus (9.8%). The length-weight analysis of the dominant species Z. platypus population showed a regression coefficient b of 3.3434 and a condition factor(k) of 0.0026, with a positive slope. The growth state of the Z. platypus population was identified as being in a very favorable condition. The Cheonggyecheon stream is considered to be an appropriate habitat for the Z. platypus population. Since the restoration, The Cheonggyecheon stream has had continuous problems due to the introduction of exotic species and invasive species and in this study, exotic species, Gyrinocheilus aymonier var.(gold type), and invasive species, Coreoleuciscus splendidus, which have not previously been reported in the Cheonggyecheon stream, appeared. Therefore, it is deemed necessary to prepare continuous publicity and management measures to prevent exotic species and invasive species from inhabiting the Cheonggyecheon stream.