• Korean Journal of Poultry Science
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• v.35 no.1
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• pp.63-69
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• 2008

The objective of this study was to investigate the effect of restricted feeding to laying performance and egg quality in brown layers. A total of 1,080 brown layer chicks were divided into three treatments; conventional feeding (ad libitum) and two restricted feedings (80% of conventional diet) for 70 weeks. One of restricted feeding started from six to eighteen weeks of age, and the other started from twelve to eighteen weeks of age. Diets were formulated by NRC (1994) recommendation. Overall laying performance and feed intake were the highest in $6{\sim}18 wk$ restricted group. But there was no significant difference among treatment group (P>0.05). Feed intake was higher in $6{\sim}18 wk$ restricted group during maximum production (P<0.05), but there was no difference between treatments after the peak. Egg quality tended to decreased by aging, but there was no significant difference among the treatments (P>0.05). The result of present study indicated that restricted feeding in rearing period of layers is beneficial to improve egg productivity and to reduce feed cost.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.3
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• pp.131-140
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• 2015

To set up unicellular cyanobacterial strains with photo-biological $H_2$ production potential, live samples were repeatedly collected from 68 stations in the coastal zone of Korea for the four years since 2005. Among 77 cyanobacterial strains established six (KNU strains, CB-MAL002, 026, 031, 054, 055 and 058) were finally chosen as the excellent strains for $H_2$ production with $H_2$ accumulation over 0.15 mL $H_2\;mL^{-1}$ under general basic $H_2$ production conditions as well as positive $H_2$ production for more than 60 hr. To explore optimum procedures for higher $H_2$ production efficiency of the six cyanobacterial strains, the inter-strain differences in the growth rate under the gradients of water temperature and salinity were investigated. The maximum daily growth rates of the six strains ranged from 1.78 to 2.08, and all of them exhibited $N_2-fixation$ ability. Based on the similarity of the 16S rRNA sequences, all the test strains were quite close to Cyanothece sp. ATCC51142 (99%). The six strains, however, were grouped into separate clades from strain ATCC51142 in the molecular phylogeny diagram. Chlorophyll- a content was 3.4~7.8% of the total dried weight, and the phycoerythrin and phycocyanin contents were half of those in the Atlantic strain, Synechococcus sp. Miami BG03511. The growth of the six strains was significantly suppressed at temperatures above the optimal range, $30{\sim}35^{\circ}C$, to be nearly stopped at $40^{\circ}C$. The growth was not inhibited by high salinities of 30 psu salinity in all the strains while strain CB055 maintained its high growth rate at low salinities down to 15 psu. The euryhaline strains like CB055 might support massive biotechnological cultivation systems using natural basal seawater in temperate latitudes. base seawater. The biological and ecophysiological characteristics of the test strains may contribute to designing the optimal procedures for photo-biological $H_2$ production by unicellular cyanobacteria.

• Fire Science and Engineering
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• v.15 no.1
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• pp.23-33
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• 2001

The utility tunnels are the important facility as a mainstay of country because of the latest communication developments. However, the utilities tunnel is difficult to deal with in case of a fire accident. When a cable burns, the black smoke containing poisonous gas will be reduced. This black smoke goes into the tunnel, and makes it difficult to extinguish the fire. Therefore, when there was a fire in the utility tunnel, the central nerves of the country had been paralyzed, such as property damage, communication interruption, in addition to inconvenience for people. This paper is based on the fire occurred in the past, and reenacting the fire by making the real utilities tunnel model. The aim of this paper is the scientific analysis of the character image of the fire, and the verification of each fire protection system whether it works well after process of setting up a fire protection system in the utilities tunnel at a constant temperature. The fire experiment was equipped with the linear heat detector, the fire door, the connection water spray system and the ventilation system in the utilities tunnel. Fixed portion of an electric power supply cable was coated with a fire retardant coating, and a heating tube was covered with a fireproof. The result showed that the highest temperature was $932^{\circ}c$ and the linear heat detector was working at the constant temperature, and it pointed at the place of the fire on the receiving board, and Fixed portion of the electric power supply cable coated with the fire retardant coating did not work as the fireproof. The heating tube was covered with the fireproof about 30 minutes.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.223-228
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• 2011

This research was performed to investigate change of green speed according to growth of grass, for this, the method of effective green management for improvement of green speed was searched by investigating green density, soil moisture, surface hardness, and mowing height every day for 6 months. As the result of the study, reliability between, green density, soil moisture, surface hardness, mowing height and green speed were measured to be respectively 0.4742, 0.5690, 0.4632, 0.2806, i.e. soil moisture is considered as the factor which affects green speed the most. Therefore, it will be an advantageous environment to maintain soil moisture a little bit low to improve green speed within the range that does not disrupt the growth of green. In case of green density, it is considered to be effective to get a fast green speed when obtaining enough density during May~June, the most vigorous growth period and at the same time green up period. Surface hardness was confirmed that management work as rolling is a considerably effective method to increase hardness. However, rolling gives high stress to the green, combining another management work as regular hilling could be a good alternative. Reliability of green preview and green speed was 0.2806, lower than soil moisture or surface hardness. Through the results, it was confirmed that management of mowing height to be low less than 3.00 mm is helpful to improve green speed, timely, and it is advantageous to manage green speed when adjusting mowing height during the vigorous growth period of bent grass. However, considering the range of mowing height was not various, being 2.9~3.4 mm, henceforth research on investigation of green speed at more various mowing heights would be necessary. Consequently, except mowing height, other three factors, i.e. green density, soil moisture and surface hardness were investigated to have considerable level of reliability on green speed, and it is considered that each factor affects green speed respectively according to green condition and time. Accordingly, in order for the manager to maintain high speed all year round, intensive care for each factor per time unit considering green growth condition is considered to be necessary.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.9
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• pp.14-23
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• 2010

This paper reports the fabrication of a DVB-T/H System in Package (SiP) that is able to receive and process the DVB-T/H signal. The DVB-T/H is the European telecommunication standard for Digital Video Broadcasting (DVB). An IC-embedded Printed Circuit Board (PCB) process, interpose a chip between PCB layers, has applied to the DVB-T/H SiP. The chip inserted in DVB-T/H SiP is the System on Chip (SoC) for mobile TV. It is comprised of a RF block for DVB-T/H RF signal and a digital block to convert received signal to digital signal for an application processor. To operate the DVB-T/H IC, a 3MHz DC-DC converter and LDO are on the DVB-T/H SiP. And a 38.4MHz crystal is used as a clock source. The fabricated DVB-T/H SiP form 4 layers which size is $8mm{\times}8mm$. The DVB-T/H IC is located between 2nd and 3rd layer. According to the result of simulation, the RF signal sensitivity is improved since the layout modification of the ground plane and via. And we confirmed the adjustment of LC value on power transmission is necessary to turn down the noise level in a SiP. Although the size of a DVB-T/H SiP is decreased over 70% than reference module, the power consumption and efficiency is on a par with reference module. The average power consumption is 297mW and the efficiency is 87%. But, the RF signal sensitivity is declined by average 3.8dB. This is caused by the decrease of the RF signal sensitivity which is 2.8dB, because of the noise from the DC-DC converter.

• Journal of dental hygiene science
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• v.10 no.3
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• pp.147-153
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• 2010

The purpose of this study was to investigate the correlation between food intake pattern body component bone mineral density(BMD) and dental caries experience of college women and we wanted to determine the correlation of these factors with dental caries experience. Research was conducted to offer basic data to develope a nutritional program for the future prevention from oral disease. The subjects in this study were 132 college women who participated in the food intake survey and who's body component and BMD was measured. The statistical analysis was done by using the SPSS 15.0 program. The results of this study were as follows; 1. The food intake pattern was not directly correlated with DMFT index. 2. The body component was not directly correlated with DMFT index. 3. The SOS, BQI was directly correlated with DMFT index(p<0.05). 4. T-score of BMD had the greatest influence on DMFT index(p<0.05). Above results indicated that bone mineral density are related with the incidence of dental caries experience and further research is necessary to develop a nutritional and health promotional program in order to prevent oral illness.

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.556-566
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• 2014

In this study, we collected 29 Kenaf (Hibiscus cannabinus L.) genetic resources from 10 countries to confirm the possibility of the introduction into Korea. The Kenaf (Hibiscus cannabinus L.) has the broad industrial use like feed and the 5 times more strong $CO_2$ absorption capacity compared to general plant. So recently it is considered as a good industrial source. We analyzed ecotype, growth and development, yield and feed value of collected resources. They were divided into 3 groups depending on flowering time, early maturing type blooming in early July, mid-late maturing type blooming from end of August to early September and late maturing type blooming in end of October. Early maturing type could get fruitful seed but dropped yield (average 7,895 kg/10a) and late maturing type could get high yield (average 12,572 kg/10a) but deletion. The other side mid-late maturing type could get yield over a certain level (average 11,207 kg/10a) and fruitful seed was ensured. The yields analyzed by resources indicated that K12 (Hongma 300) collected in China, K25 from India, K22 from Russia and K21 (Khonkaen 60) variety from China were more than 13,500 kg per 10a. Feed value of early maturing type had inclined to more better than other types, but like dry digestible matter (DDM) and dry matter intake (DMI) of some late maturing types like K12, K21, K22 which had a high yielding ability were more better than that of early maturing types'. So relative feed value (RFV) which considered comprehensive item for feed value were indicated K21 was 102.5, K12 was 116.2 and K22 was 120.2. 'Jangdae' the variety developed in Korea which could complement of other types' had a good quality for yield 10,975 kg/10a and 12.5% crude protein content and 101.9 of the relative feed value. So we need to be taken power to collection of mid-late maturing types resources.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.480-493
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• 2007

Many railway-advanced countries are using the various types of track to reduce the track maintenance and repair cost according to the improvement of velocity. It spends on much maintenance and repair cost for ballast track due to abrasion of ballast, track irregularity and unisotropical ballast-support stiffness. The ballast track on railway bridge is accelerating the deterioration of ballast according to interaction of railway bridge and track. As continuing the deterioration, it is caused dynamic loads. Due to these effects, it increases negative loads of track and bridge. However, when designing the railway bridge, the effect of ballast track was applicate only dead load, so elastic behavior effect of ballast track is not influenced. Therefore, this paper presumes the stiffness of ballast track on railway bridge considering dynamic behavior of railway bridge, it was evaluated that effect on dynamic behaviors of railway bridge according to ballast track stiffness.

• The Journal of the Petrological Society of Korea
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• v.2 no.2
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• pp.74-94
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• 1993

Metabasites and metapelites in the Mungyong area were intruded by Cretaceous granites with radius of 4-8 km. As the distance from granite body increases, the mineral assemblage of metabasite changes from amphibole + plagioclase through amphibole + plagioclase + epidote to amphibole + plagioclase + epidote + chlorite. The compositional variations of amphibole and plagioclase according to the change of metamorphic grade and bulk rock compositions are very complex. Towards the Mungyong Cretaceous granite body, the mineral assemblage of metapelite changes from chlorite+ muscovite(ch1orite zone) through biotite + chlorite + muscovite(biotite zone) to andalusite+biotite + muscovite${\pm}$chlorite or cordierite+ biotite+ muscovite${\pm}$chlorite(cordierite zone). The estimated metamorphic conditions of cordierite zone are 480~$580^{\circ}C$ 1.5-3.3 kb. The theoretical study on the thermal metamorphism caused by the Cretaceous granite with radius longer than 4 km in the Mungyong area suggests the followings: The degree of metamorphism is mainly determined not by the size of granite body but by the temperature of granite intrusion; The country rocks within 2 km from Cretaceous granite have undergone metamorphism with temperature higher than $500^{\circ}C$, which is consistent with the petrological study in the Mungyong area. Mungyong Cretaceous granite caused a low P/T thermal metamorphism to the country rocks; the amphibolite facies metamorphism to the country rocks within 1-2 km from the granite body and the epidote-amphibolite and greenschist facies metamorphism to the country rocks within 2-5 km.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.1-15
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• 2015

Before the advent of pasteurization and other microbiological controls in the dairy industry, milk product-borne diseases such as scarlet fever, typhoid fever, septic sore throat, and tuberculosis were globally widespread. Pasteurization was invented by Louis Pasteur, and it has been considered as one of the most effective ways to control milk product-borne diseases since the 20th century. Nevertheless, till date, various types of cheese in the EU, the USA, and other countries are made from unpasteurized milk as artisan cheese, following the specific food regulations of each nation. Furthermore, after the effectiveness of the Free Trade Agreement (FTA) negotiations between Korea and many nations, the import of various types of cheese made in different conditions and influenced by acidity, preservatives, temperature, competing flora, water activity, and salt concentration increased yearly. Hence, the objective of this review was to describe (1) the 60-day aging rule of cheese, (2) characteristics of the outbreaks linked to cheese manufactured from unpasteurized milk since 1998 to 2011 in USA, and (3) serious health risks from unpasteurized milk, to ensure food protection and safety and to use this basic information for risk assessment.