• Journal of Ginseng Research
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• v.23 no.2 s.54
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• pp.93-98
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• 1999

In order to evalulate the qualities of red ginseng extract and decrease precipitate fonnation in ginseng drink, red ginseng extract was hydrolized with ${\beta}-amylase$ and transglucosidase. $5.2\%$ isomaltose was produced as isomaltooligosaccharides and glucose content was increased in the enzyme treated ginseng extract. Contents of ginsenoside $R-b_1\;and\;R-b_2$ were decreased, whereas ginsenoside-Rd was increased by the enzyme treatments. The growth of 3 strains of bifidus spp. and 4 strains of lactobacillus spp., beneficial intestinal bacteria, were enhanced by adding of the enzymatically hydrolized ginseng extract. Sweetness and sourness were increased, however, bitterness and astringency were decreased in the hydrolized ginseng extract. The fonnation of precipitates in hydrolized red ginseng extract of $pH\;3.0\~4.5$ were significantly decreased in the storage condition of $40^{\circ}C$ for 1 month compared to that of control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.2
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• pp.135-142
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• 1996

Two experiments were conducted to investigate the utilization of various types of fish meal as dietary protein sources in Korean rockfish (Sebastes schlegeli). In the first experiment, averaging 5.7 g fish were divided into two groups and fed one of diets containing $55\%$ steam-dried white fish meal (SWFM) or $55\%$ brown fish meal (BFM) for 45 days. Weight gain and feed efficiency from fish fed SWFM were significantly (P<0.05) higher than those from fish fed BFM diet. However, daily feed intake, protein retention and lipid retention were not influenced by the two different diets. In the second experiment, averaging 86.6 g fish were divided into six groups and fed one of diets containing $56\%$ SWFM, $28\%\;SWFM+31\%$ flame-dried white fish meal (FWFM), $62\%\;FWFM,\;28\%\;SWFM+31\%\;BFM,\;56\%\;BFM$, or $28\%\;SWFM+29\%$ hydrolyzed fish protein (HFP) for 21 weeks. No significant differences were found among fish fed the six different diets in weight gain, feed efficiency, condition factor, whole body composition, and relative liver weight. Results of the present studies indicated that fish size should be considered in selecting feed ingredients and also feed cost could be lowered by replacing SWFM with FWFM or BFM in growing Korean rockfish diet.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.116-127
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• 2017

A fog on road is known as a weather factor that affects traffic flow. The method in order to solve the problem, recently, Variable Speed Limit(VSL) which provide reasonable speed limit by road and weather conditions in real time is introduced. However, if drivers do not comply with VSL, the road safety more decrease than without VSL because individual vehicle's speed deviation is larger than without VSL. Therefore, this paper aims to analyze to speed limit compliance and traffic characteristics under foggy conditions with and without VSL. A test using driving simulator divides into normal and foggy condition with visibilities are 200m, 150, 50~100m. The test results showed that 70 subjects's average speed mostly obeyed speed limit, but speed deviation generally declined with VSL. Especially, the speed deviation more reduced under foggy conditions. According to this study, compliance of VSL clearly rose in low visibility and VSL helped improve road safety due to reduction of speed deviation. The results of this study are expected to make use of reasonable speed limit for reference.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.5
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• pp.421-427
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• 2014

Most of the structure of the real world is influenced under dynamic loads. However, when structure analysis and the structural optimization is performed, it is assumed that the static load acts on structure. When considering the actual load of dynamic loads in order to take into account a variety of loads, computational resources and time becomes a big burden in terms of cost. However, considering only the simple static load condition is not preferable for structural safety. For this reason, a lot of studies have been conducted trying to compensate this trouble by applying weight factor or replacing dynamic load with the equivalent static load. In this study, structural optimization techniques for structures under dynamic loads is proposed by applying the equivalent static load. From previous study, after determining the positions of equivalent static load based on primary degrees of freedom, the equivalent static load is calculated through the optimization process. In this process, the equivalent static load optimization of previous research is complemented by adding constraints to avoid excessively large load extraction. In numerical examples, dynamic load is applied to the truss structure and the plate. Then, the reliability of the proposed optimization technique is verified by carrying out size optimization with the equivalent static load.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.247-253
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• 1996

Microscopic analysis has been performed in order to investigate effects of the microstructure of the starting feed rods on the morphology of the S-L interface and the stability of the molten zone during single crystal growth of $SrTiO_{3}$ using a floating zone method. Undoped and $Fe_{2}O_{3}$ doped $SrTiO_{3}$ doped $SrTiO_{3}$ specimens, sintered at the different temperatures have been used. In the case of the feed rods sintered at the lower temperature($1400^{\circ}C$), the poor densification made the stability of the molten zone difficult to maintain. The feed rods sintered at the higher temperature ($1600^{\circ}C$) exhibited the higher density but their molten zone was difficult to maintain due to the presence of the abnormally grown grains. It is concluded that the uniform grain size distribution of the feed rod is the critical factor to maintain the stable molten zone and therefore to give optimum growth condition during FZ single crystal growth.

• Journal of Navigation and Port Research
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• v.44 no.4
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• pp.275-282
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• 2020

Recently, the occurrence of a ship capsizing was analyzed as the main cause of the lack of stability or loss because of the improper management of the center of gravity, the movement of cargo or heavy weight when excessive steering occurs or when navigating during bad weather. Thus, to prevent a ship from capsizing, it is necessary to secure stability to enable the ship's return to its upright position, even if a dangerous heel occurs. The GM is a crucial evaluation factor regarding stability, which the navigation officer uses to preserve stability. In this study, based on the stability data collected from the operating of ships for five years, The GM by ship's type according to the operating status was analyzed specifically such as a ship's length, breadth, and gross tonnage. The feature of the GM distribution according to a ship's length was confirmed, and after performing the correlation analysis between the breadth and the GM, the ratio of the GM to breadth was calculated, and the result was compared with the previous ratio. Additionally, a simple approximation formula and minimum GM for the estimation of the GM by ship type were proposed by the regression analysis of the GM using the gross tonnage (GT)/breadth (B) to reflect the trend of larger ships being built. The results of this study are expected to be used as data for the review of securing a stable GM on ships.

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.561-569
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• 2014

In construction site, BIM is used in part of construct-ability review and design mistake checking. However, in a current domestic construction site, except public order project, most of work in private order project has been processing based on 2D work. As an expert resists to certain point in introduction of new technique, it may be shown in the introduction of BIM. For this, We need to analysis construct-ability of introducing BIM, work field of introducing and operational capability about present domestic construction engineers. Therefore, this study solves the problem of existing construct-ability analysis, and it visualizes the various information and objects for an effective job performance. Furthermore, construct-ability analysis by BIM that can use an intergrated management is theoretically examined and practical field-application priority among conclusions is proposed through a survey targeting on the hand-on worker. Therefore, this study suggests a factor supplying for a business-centric introduction plan and support condition.

• Journal of Aquaculture
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• v.17 no.2
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• pp.122-127
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• 2004

On protein equivalence base, fishmeal (FM) was replaced by lysine cell mass (LCM) in selected different diets in Korean rockfish, Sebastes schlegeli (Hilgendorf) Eight experimental diets were formulated to contain 100% FM (LC $M_{0}$), 90% FM+10% LCM (LC $M_{10}$),80% FM+20% LCM (LC $M_{20}$), 70% FM+30% LCM (LC $M_{30}$), 60% FM+40% LCM (LC $M_{40}$ ), 70% FH+30% LCM+lysine (LC $M_{+Lys}$), 60% FM+40% LCM+lysine (LC $M_{40+Lys}$), and 50% FM+50% LCM+lysine (LC $M_{50+Lys}$). Experimental individuals of the fish (12.6 g) were randomly fed on one of the experimental diets. After 6 weeks of feeding trial, weight gain (WG) and feed efficiency (FE) of fish fed LC $M_{0}$ diet was significantly (P〈0.05) higher than those of fish fed LC $M_{20}$, LC $M_{30}$, LC $M_{40}$ , LC $M_{30+Lys}$, LC $M_{40+Lys}$, and LC $M_{50+Lys}$ diets, however, there was no significant difference in WG of fish fed LC $M_{0}$ and LC $M_{10}$ diets. Supplementation of lysine has no effect on WG. There was no significant difference in condition factor (CF) of fish fed LC $M_{0}$, LC $M_{10}$ and LC $M_{20}$ diets. Hemoglobin (Hb) of fish fed LC $M_{0}$, LC $M_{10}$, LC $M_{20}$, LC $M_{30}$, LC $M_{40}$ , LC $M_{30+Lys}$, and LC $M_{40+Lys}$, diets were not significantly different from each other. No significant differences were observed in hematocrit (PCV) and hepatosomatic index (HSI) among all dietary treatments. Apparent digestibility of dry matter (ADM) and protein (ADP) of diets significantly decreased with increase in dietary LCM level, though there was no difference in ADM and ADP between LC $M_{0}$ and LC $M_{10}$. These results indicate that LCM could replace up to 10% of fishmeal in Korean rockfish diets.ish diets.iets.ish diets.s.ish diets.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.9
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• pp.1045-1050
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• 2014

$N_2O$(Nitrous Oxide) is known as the third major GHG(Green House Gas) following $CO_2$(Carbon Oxide) and $CH_4$(Methane). The GWP(Global Warming Potential) factor of $N_2O$ is 310 times as large as that of $CO_2$ because $N_2O$ in the atmosphere is very stable, and it becomes a source of secondary contamination after photo-degradation in the stratosphere. Investigation on the cause of the $N_2O$ formation have been continuously reported by several researchers on power sources with continuous combustion form, such as a boiler. However, in the diesel engine, research on $N_2O$ generation which has effected from fuel components has not been conducted. Therefore, in this research, author has investigated about $N_2O$ emission rates which was changed by nitrogen and sulfur concentration in fuel on the diesel engine. The test engine was a 4-stroke direct injection diesel engine with maximum output of 12 kW at 2600rpm, and operating condition of that was set up at a 75% load. Nitrogen and sulfur concentrations in fuel were raised by using six additives : nitrogen additives were Pyridine, Indole, Quinoline, Pyrrol and Propionitrile and sulfur additive was Di-tert-butyl-disulfide. In conclusion, diesel fuels containing nitrogen elements less than 0.5% did not affect $N_2O$ emissions in the all concentrations and kinds of the additive agent in the fuel. However, increasing of the sulfur additive in fuel increased $N_2O$ emission in exhaust gas.

• Journal of Bio-Environment Control
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• v.24 no.1
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• pp.27-33
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• 2015

High temperature stress in summer season at plastic house is a limiting factor for tomato fruit set and yield. This study was performed to assess the effects of gibberellic acid ($GA_3$) and 2,4-Dichlophenoxy acetic acid (2,4-D) spray on fruit set, yield, and quality of tomato cv. 'Adoration'(Enza Zaden Co., Ltd.) under the plastic house in Hwacheon, 2011. Four concentrations (0-, 5-, 10- and $15mg{\cdot}L^{-1}$) of $GA_3$, and three concentrations (0-, 5- and $10mg{\cdot}L^{-1}$) 2,4-D were sprayed in early flowering of tomato in the plastic house, and fruit set, yield and quality characters were observed. The results showed that spray of $10mg{\cdot}L^{-1}$ $GA_3$ significantly increased the fruit set by 14.2% than unsprayed. The spray of $GA_3$ significantly increased the marketable fruit number, fruit weight, and yield. The spray of 2,4-D on blossoms significantly affected the fruit set percentage, fruit weight, marketable fruit weight and yield, and the highest fruit set observed as 62.5% in combined spray of $GA_3$ and 2,4-D at each $5mg{\cdot}L^{-1}$. Fruit size and total soluble solids significantly varied with the concentrations of $GA_3$ sprayed. The result indicates that the spray of $10mg{\cdot}L^{-1}$ $GA_3$ and $5mg{\cdot}L^{-1}$ 2,4-D can be more economic and effective to increase the fruit set, and yield in tomato under high temperature condition in plastic house.