• Journal of Aquaculture
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• v.20 no.3
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• pp.160-167
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• 2007

Embryonic and pre-leptocephalic larvae development of the eel, Anguilla japonica, are described following natural fertilization in the indoor tank of $23^{\circ}C$ water temperature. Following a routine hormone treatment technique for the brood stock, female eels were artificially matured by weekly intramuscular injections of salmon pituitary extracts (SPE) at a dosage of 20 mg/kg body weight (BW) for a total of 10-14 doses to induce ovarian maturation, while male eels received weekly intramuscular injections of human chorionic gonadotropin (HCG) at a dosage of 1 IU/g BW for a total of 6-10 doses to induce testicular maturation in a separate aquarium and induced natural spawning. Fertilized eggs of about 1.0 mm in diameter were pelagic and showed a typical discoidal cleavage. Hatching occurs 38 hrs after fertilization at a water temperature of $23^{\circ}C$. The newly hatched larvae measured about 3.0 mm in total length and the number of myomeres averages 42. Their mouths and anuses were opened at 4.5 days and the yolk sacs of the pre-leptocephalic larvae were almost absorbed at 6.5 days after hatching. Pre-leptocephalic larvae survive for 14.5 days. At this time they are $5.87{\pm}0.25mm$ in total length and have about 98 myomeres. However, morphological characterization of embryonic and pre-leptocephalic larvae were not different between natural fertilization and artificial fertilization by the dry method.

• Journal of Aquaculture
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• v.15 no.2
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• pp.111-117
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• 2002

Effect of substrate composition, stocking density and food organisms on survival and growth of the surf clam, Spisula sachalinensis was studied. Spat collection from the substratum was the highest, when its sand size was less than 250 $\mu m4; at such substratum, survival and growth of the surf clam were also the highest. The spat (1.4 mm) grew to 4.6 mm and 8.2 mm in shell length on day 30 and 50, respectively. The relationship between shell length (SL) and shell height (SH), shell breadth (SB), total weight (TW) and shell weight (SW) of the spat are formulated by the following equations; SH : 0.7351SL+0.2272 ( $r^2$ =0.9600)i SB = 0.4037SL+0.2112 ($r^2$ = 0.9452); TW : 0.2824SL^{2.7020} ($r^2$ = 0.9820)i SW = $0.4021SL^{2.0217} ($r^2$ : 0.6169). In the substratum containing fine sand, growth and survival of the clam roared at the density of 1~2 ind./$cm^2$ were optimal. The quality of feed decreases in the following order; C. calcitrans, mixture group, I. galbana, P. lutheri, T. suecica.

• Journal of Aquaculture
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• v.10 no.3
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• pp.289-300
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• 1997

Energy budget of mysid shrimp, Neomysis intermedia in Lake Kyongpo was determined at constant temperature (2$0^{\circ}C$). Energy used by reared mysids were calculated from data on feeding, growth, molting, reproduction, and metabolism. The Energy used by growth of juvenile and adult were 6.87 cal in females of 8.55mm in length, and 5.67 cal in males of 7.53mm in length, respectively. Molting losses were estimated to be 0.46 cal in females and 0.38 cal in males from juvenile to adult. Energy used in respiration were estimated to be 48.48 cal in females and 36.45 cal in males from juvenile to adult. The energy intakes from feeding were 84.15 cal in females and 67.09 cal in males from juvenile to adult. Energy losses by excretion were 10.36 cal in females and 6.46 cal in males. Thus, females assimilated 86.65% and males 81.99% of assimilated energy in somatic growth. The gross growth efficiencies (k1) showed 8.71% for females and 9.02% for males and the net growth efficiencies (k2) showed 10.05% for females and 12.36% for males. Maintenance costs were estimated at 66.48% of assimilated energy in females and 66.26% in males. Molting losses among the energy assimilated from juvenile to adult were estimated to be 0.63% in males and 0.69% in females.

• Journal of Aquaculture
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• v.19 no.2
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• pp.109-118
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• 2006

The recent decrease in wild stocks of seahorse, Hippocampus coronatus, has prompted the production of the species in captivity. We here present data on the body color changes of the species according to culture conditions. This investigation examined relationship between adult body size and clutch and growth in 60 days after parturition and survival of juveniles with four fed enriched Artemia nauplii, copepod nauplii and copepod adult. Seahorse adults ($77.77{\pm}9.84mm$, n=12) collected from Kamak Bay and Yeoja Bay from August 2003 to November 2004 gave a parturition of $6\sim75$ juveniles (Mean, 39 juveniles/male/time) for 14 times. A day old seahorses were $14.48{\pm}1.38mm$ (n=15) in standard length (SL) with 14 dorsal fin rays, 12 pectoral fin rays and 4 anal fin rays. Sixty-day old seahorses were $24.65{\pm}0.83mm$ (n=4) in SL. Growth rate of seahorses was 0.18 mm/day at 24 in 60 days after parturition. When offered Artemia nauplii and copepod nauplii, 5 day old sea-horses preferred copepod nauplii to Aremia nauplii with a maximum predation rate of 31 copepod nauplii/sea-horse/h. However 30-day old seahorses preferred selected Artemia nauplii with a maximum predation rate of 14 Artemia nauplii/seahorse/h. Survival was highest (49%) when offered copepod nauplii together with enriched Artemia nauplii.

• Journal of Aquaculture
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• v.19 no.3
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• pp.216-221
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• 2006

The Effect of different temperatures and photon irradiance on the growth of crust and the regeneration of tissue fragments of the commercially important red alga Grateloupia acuminat Okamura were examined in laboratory cultures. The tetraspore developed into basal crusts and produced upright thalli. Crust grew very fast at $25^{\circ}C$ and $80{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ after one week in indoor culture. However, they stopped growing after three weeks. Maximum growth was $275{\mu}m$ in diameter. They required four weeks to get upright thalli at $5^{\circ}C$, while only three weeks were required at $10^{\circ}C$. When different light intensities were compared at $15^{\circ}C$, cells of the crusts were well differentiated $80{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and consistently divided so that upright thalli were produced. In aeration culture, the upright thalli grew up to 6.5 cm in length within 4 months. Thus, it is possible to produce mass cultures of Grateloupia in the field. In addition, female and male gametophytes developed from the tetraspores and they were fertilized to produce tetrasporohyte thalli. By this procedure, the normal life cycle of the red alga G. acuminata was completed.

• Korean Journal of Heritage: History & Science
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• v.47 no.3
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• pp.4-23
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• 2014

Seokjojeon Hall is the Neoclassic style building situated in Deoksugung Palace, which was proposed by John McLeavy Brown who was a chief commissioner of the Daehan Empire and designed by John Reginald Hardings in 1897. Construction of the Seokjojeon Hall began in 1900 and completed in 1910 at the total cost of one million won. Decorating and furnishing of the interior was designed by Lovell and all the furniture of Seokjojeon Hall had been purchased from Maple&Co. The Maple&Co was the supplier of luxury furnitures and decorating items for luxurious residentials, hotels, embassies and the palaces and its headquarter was located in London. Ready-made furnitures were purchased as shown in the Maple's catalog. The designs and styles of the west were applied to Seokjojeon Hall. That is one of the aspects showing Daehan Imperial underwent a period of Westernization.

• Journal of Korean Home Economics Education Association
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• v.34 no.2
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• pp.1-19
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• 2022

The purpose of this study is to analyze the keywords of the middle school textbooks based on the 2015 revision of the technology and home economics curriculum to understand the core concepts and contents composition of the 'housing' unit. Using TEXTOM and UCINET programs, the frequencies and centralities of the keywords were analyzed, and CONCOR analysis was performed. The results are as follows. First, the content system of the 'housing' unit is divided into 'life culture' and 'safety' in the 'family life and safety' area. Second, in the 'safety' section, the frequencies of occurrence of the words were high in the order of indoor, occurrence, use, noise, and safety accidents, in the order of frequency of occurrence. It was confirmed that words related to daily life, safety accidents, and prevention were closely connected to each other. In the 'life culture' section, the frequencies of occurrence were high in the order of space, housing, family, and residential space, and the correlations between these keywords were also high. Third, the most influential core keywords were, indoor and occurrence in the 'safety' section, and space, family, and housing, in the 'life culture' section. Fourth, the 'safety' section were divided into two subunits, 'safe living environment' and 'comfortable living environment', and the 'life culture' section were divided into four subunits, 'living space composition', 'space utilization', 'housing value and lifestyle', and 'housing culture'.

• Korea Science and Art Forum
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• v.19
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• pp.405-415
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• 2015

Recently the development of China has attracted all over the world, many scholars of different areas are interested in Chinese Culture and Chinese Market. After sixties of last century development of the economic of the South Korea closer to modernization, but there are many problems, one of them is the urban living style boasts of the features of concentration. Because of this phenomenon the lack of housing space become more serious. It also come to be a social problems. Therefore narrow residential area become inevitability. At the same time, effective utilization of housing space become a demand. Especially for those families with limited living space, it's meaningful for them. Between the China and the South Korea. Chinese have the same situation too, the different is kitchen space of chinese is closed. It means they have to cook in limited space. With increased supplies and more small appliances, an inevitable requirement is opening out the kitchen space, but unreasonable furnishings and living space reduces the efficiency of the kitchen, which has led to the discontent of users. From this, base on the investigation and analysis of diet&living space of most chinese apartment, and through differences kinds and places of storage items. With them I would combine the food culture and feature of storage space of China to solve problems of the efficiency of the kitchen.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.29-31
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• 1981

The eels Anguilla japonica were reared in an indoor aquarium of $1m{\times}1m{\times}0.67m$ from June 7 to August 8, 1980. The eels used for the experiment were the smallest ones which were left over from 1974 to 1976 groups, of which the others grew out years earlier. The eels were fed pelletized feed, with the results of 1.05 to 1.678 in feed coefficient, and 0.96 to $1.46\%$ in daily growth rate. The results are well comparable to those of paste feed, which has been being used in the eel farming industry up to date and will be as well used in the future, if any innovative way will not be developed. If pelletized feed can be used without any other hazards, the cost of feed will be remarkably reduced by eliminating costly $\alpha-starch$ which is absolutely necessary for the paste feed preparation, and also by preventing scattering of feed materials which is always associated with paste-feed during feeding time.

• Journal of the Korean Geotechnical Society
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• v.39 no.1
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• pp.5-14
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• 2023

The pile driving process may lead to ground heaving, causing additional positive skin friction to act on the piles, compromising their stability. This study proposes a new pile foundation type that can reduce positive skin friction. This was investigated by designing and constructing a pile with a hydraulic cylinder which actively responds to ground deformation. The newly proposed pile design was compared against traditional piles in multiple model tests where ground heaving was simulated. In the tests, base load and total shaft resistance were measured during ground heaving and with expansion of the hydraulic cylinder. As a result of the tests, a very small amount of expansion of the hydraulic cylinder member completely reduced the positive skin friction and increased the base load. Excessive expansion of the hydraulic cylinder, however, generates negative skin friction beyond the zero skin friction state. Therefore, it is necessary to estimate the appropriate level of hydraulic cylinder expansion, taking into account the amount of ground heaving and the allowable displacement of the pile.