• Title/Summary/Keyword: Rearing system

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Spawning behavior and Morphological Development of the Eggs and Larvae of the Fringed blenny, Chirolophis japonicus from Korea (Pisces: Stichaeidae) (한국산 괴도라치 (Chirolophis japonicus)의 산란행동, 난 발생과 자어의 형태발달)

  • Park, Jae Min;Lee, Sung Hun;Choi, Jae Young;Han, Kyeong Ho
    • Korean Journal of Ichthyology
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    • v.27 no.2
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    • pp.63-70
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    • 2015
  • This research is about spawning behavior and morphological development of the eggs and larvae of fringed blenny which lives in Korean sea. It helps to find out the relation between fringed blenny larvae and other stichaeidae larva. Moreover, it is going to use for the basic data of taxonomical research. There were 8 mother fishes (total length 31.8~34.0 cm, average $32.9{\pm}0.21cm$), which were captured from the cost of Sindeok-dong, Yeosu-si, Jeollanam-do from December, 2010. we used trap to capture them. Mother fishes were brought to glass aquarium ($50{\times}30{\times}35cm$) and nurtured with recirculate rearing system. Breeding water temperature was $12.3{\sim}15.8^{\circ}C$ (average $14.1{\pm}2.47$) and salinity was 32.5~33.5‰ (average $33.0{\pm}0.05$‰). fertilized egg was round, opaque demersal egg. The size was 1.81~2.19 mm (average $2.00{\pm}0.27mm$, n=50). Incubation was begun after 271 hours and 30 minutes from fertilization. It started with piercing the egg membrane. prelarvae had length of 8.45~8.84 mm (average $8.65{\pm}0.28mm$, n=5) right after the incubation, and both mouth and anus were opened. After 11 days from the incubation, postlarvae had length of 10.5~11.3 mm (average $10.9{\pm}0.57mm$), and the number of myotomes was increased to 66.

Study on the Psychological Well-Being of Employed Married Women with Children in Early Childhood - Focused on family and social support system variables - (유아기 자녀를 둔 취업여성의 심리적 복지에 관한 연구 -가족 및 사회지원체제 변인을 중심으로-)

  • Kang, Ran-Hye
    • Korean Journal of Childcare and Education
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    • v.6 no.2
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    • pp.155-173
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    • 2010
  • The purpose of this study was to find factors affecting the psychological well-being of married working women in Seoul. For this purpose, survey data form 332 employed married women residing in Seoul are used to evaluate the relative effects of Psychological well-being of married working women. Survey questions included demographic information, housework and child-rearing related variables, work related variables, variables related with social support systems, items on child care services for the preschoolers, and psychological well-being of married working women. The major findings were as follows: 1) The psychological well-being of married working women score is 36.14(mean score is 32). The difference between the psychological well-being of married working women varied this according to socio-demographic variables: educational level, income level, spouse's support, occupation, and job satisfaction. 2) The factors that affected psychological well-bing were amount of household labor by husband, job satisfaction, socio-support systems, and educare service satisfaction. 3) The factor that had the most significant impact on the psychological well-being of married working women is job satisfaction. It is suggested to utilize the Employment Assistant Program to establish friendly working environment for married women.

Egg-forming and Preservation Methods of the Emma Field Cricket Eggs, Teleogrylius emma (Orthoptera: Gryllidae) (왕귀뚜라미(Teleogryiius emma)알의 실내 인공 채란 및 저장)

  • Kim Namjung;Hong Seong-Jin;Seol Kwang-Youl;Kwon Ohseok;Kim Seong-Hyun
    • Korean journal of applied entomology
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    • v.44 no.1 s.138
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    • pp.61-65
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    • 2005
  • Egg-forming and preservation methods for the indoor-rearing system of the emma field cricket, Teleogryllus emma, were investigated. The oviposition preference experiment on different mats, soil(natural oviposition mat) and $oasis^{\circledR}$(artificial oviposition mat), showed that T. emma preferred to oviposit on the $oasis^{\circledR}$. On the other hand, $oasis^{\circledR}$ had more inactive number of eggs laid per female and hatchability than another. However, the number of eggs laid per female and hatchability within 50 days after emergence were better than soil. The experiment on the hatching of the eggs showed that eggs could be stocked at $10^{\circ}C$ for 40 days with 14 day pre-period after laying, representing $62.1\%$ hatchability, when considering generation shortening. On the other hand, When it had been kept in cold storage for 90 days at $7.5^{\circ}C$ with 14 day pre-period after laying it, appeared to be the most suitable for long period-storage method by hatchability $65.1\%$.

The Optimum Feeding Frequency in Growing Korean Rockfish (Sebastes schlegeli) Rearing at the Temperature of 15℃ and 19℃

  • Mizanur, Rahman Md.;Bai, Sungchul C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.9
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    • pp.1319-1327
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    • 2014
  • Two feeding trials were conducted to determine the optimum feeding frequency in growing Korean rockfish, (Sebastes schlegeli) reared at the temperatures of $15^{\circ}C$ and $19^{\circ}C$. Fish averaging $92.2{\pm}0.7$ g (mean${\pm}$standard deviation [SD]) at $15.0{\pm}0.5^{\circ}C$ and $100.2{\pm}0.4g$ ($mean{\pm}SD$) at $19.0{\pm}0.5^{\circ}C$ water temperature were randomly distributed into each of 15 indoor tanks containing 250-L sea water from a semi-recirculation system. A total of five feeding frequency groups were set up in three replicates as follows: one meal in a day at 08:00 hour, two meals a day at 08:00 and 17:00 hours, three meals a day at 08:00, 14:00, and 20:00 hours, four meals a day at 08:00, 12:00, 16:00, and 20:00 hours, and one meal every 2 days at 08:00 hour. Fish were fed at the rate of 1.2% body weight (BW)/d at $15^{\circ}C$ and 1.5% BW/d at $19^{\circ}C$. At the end of 8 wks of feeding trial weight gain and specific growth rate were significantly higher at the fish fed groups of one meal a day and two meals a day at $15^{\circ}C$ and fish fed groups of 1 meal every 2 days at $19^{\circ}C$ were significantly lower than those of all other fish fed groups. Glutamic oxaloacetic transaminase and glutamic pyruvic transaminase of fish fed group at 1 meal every 2 days was significantly higher than those of all other fish fed groups in both experiments. Weight gain, specific growth rate and condition factor were gradually decreased as the feeding frequency increased. The results indicate that growing Korean rockfish 92 and 100 g perform better at $15^{\circ}C$ than $19^{\circ}C$ water temperature. As we expected, current results have indicated that a feeding frequency of 1 meal a day is optimal for the improvement of weight gain in growing Korean rockfish grown from 92 g to 133 g at $15^{\circ}C$ and 100 g to 132 g at $19^{\circ}C$ water temperature.

Sanitary Control of Aquarium Tank Water with U.V. Light (자외선을 이용한 활어용 수조수의 위생 대책 수립)

  • CHOI Seung-Tae;PARK Mi-Yeon;CHANG Dong-Suck
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.4
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    • pp.428-434
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    • 1995
  • The purpose of this study is to develop a sanitary aquarium for the safety slices of raw fish by using U.V. light. Water re-circulating system was composed of two tanks. One of the tanks $(90\times45\times45cm\;in\;size),$ was used for rearing fish and the other $(90\times45\times45cm\;in\;size),$ with 37 pieces of corrugated plastic plates was used for the growth of Nitrosomonas and Nitrobacter to remove ammonia from the water. Consequently, bactericidal effects of U.V. light were examined under the controlled condition of water with flow rate 730m1/sec (water flow thickness: 10mm), the width 41cm of water flow route, and the distance 4.75cm from the lamp to its water bottom, and U.V. light 75W (5 lamps). The water of the aquarium tank will be theroetically circulated 1 cycle per 18 min. In these conditions the bactericidal effect was $85\%$ just after passing through U,V. light and 3 log cycle in aquarium tank water. The count of Vibrio parahaemolyticus just after irradiation was decreased by about over than 3 log cycle. Under the irradiation for 72 hours, viable cell counts in both skin and gill of fish reared were decreased into about 2 log cycle, but there was no significant decrease in viscera. When the temperature of the tank was controlled at about $20-23^{\circ}C$ under the same condition, viable cell counts were reduced about 2 log cycle, and fecal coliforms were reduced about 1 log rycle and 3 log cycle in Crassostrea gigas and Mytilus edulis, respectively.

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Antibacterial Effects of Pseudomonas aeruginosa MB I-3 against Listonella anguillarum (어류 병원세균, Listonella anguillarum에 대한 Pseudomonas aeruginosa MB I-3의 항균 효과)

  • Lee, Su-Jung;Youn, I Na;Kim, Jin-Do;Lee, Jung Sick;Kim, Eunheui
    • Journal of fish pathology
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    • v.27 no.1
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    • pp.17-24
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    • 2014
  • To study the possible use of probiotics in fish farming, The in vitro and in vivo antibacterial effects of Pseudomonas aeruginosa MB I-3 (MB I-3) against the fish pathogenic bacterium Listonella anguillarum were evaluated. The inhibitory effects of MB I-3 against vibrios were investigated by the double layer method and the co-culture. The results showed that MB I-3 inhibited the growth of pathogenic vibrios including Listonella anguillarum, Vibrio alginolyticus, Vibrio cholerae, Vibrio fluvialis, Vibrio furnissii, Vibrio harveyi, Vibrio parahaemolyticus and Vibrio vulnificus. Extracellular substances obtained from the cultural supernatant of MB I-3 by ethyl acetate extraction showed inhibitory effects on L. anguillarum. The antibacterial substance of MB I-3 was evaluated to destroy the cell membrane of L. anguillarum in electron micrographs. The probiotic effects of MB I-3 was tested by exposing olive flounder (Paralichthys olivaceus) fry to L. anguillarum with or without MB I-3. The cumulative mortality of olive flounder fry infected with L. anguillarum was 24% in the group with MB I-3, while it was 46% in the control group without MB I-3. These results indicate that MB I-3 has potential applications as a probiotic for the control of fish pathogenic vibrios in fish rearing system.

Quantitative Observation on the Behavior of the Smoky Brown Cockroach, Periplaneta fuliginosa(Seville): Presence at Important Micro-havitats of Rearing Cages in the Laboratory (먹바퀴, Periplaneta fuliginosa(Seville), 습성의 계량적 관찰: 실험실내 사육상의 중요 미소서식처에서의 출현)

  • 전태수;박영석
    • Korean journal of applied entomology
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    • v.32 no.3
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    • pp.354-371
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    • 1993
  • Behavior of adult females of the smoky brown cockroach was observed for 10-15 days continuously by using computer and the automatic sensoring system. Under the light condition of l2L~ 12D, individual variations were generally higher and the periodicity appeared less in terms of the presence time at the micro-habitats and the locomotory activity. The smoky brown cockroach appeared 20.42, 11.50, 6.31 and 2.66 % in a day in averages respectively at the shelter and the places for other individuals, feeding and drinking. It stayed 20.29 % in a day at the shelter when food, water, and other individuals were not supplied. Visiting rates were higher at the feeding and dnnking places than at. the ot.her micro-habitats. The degree of t.he locomotory activity was relatively lower when food, water, and other individuals were not supplied t.han when they were supplied. The Pnncipal Component Analysis (PCA) on the presence at the micro-habitats showed that. t.he presence pattern for each mdividual appeared differently (Q mode) while the differem time zones were grouped to the photophase and scotophase (R mode). When food, water, and other individuals were supplied the degree of grouping was higher at the shelter than at the places for feeding and drinking. When the act.ivityand the presence time at the different micro-habitats were jointly analyzed by PCA, the achvity of the female smoky brown cockroach appeared in relation with the presence time ( %) at the places for feeding and other individuals.

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Comparison Between South and North Korean Terminologies in Child and Family Domains of Family Life Education (남북한 가정생활교육 관련용어 비교분석 - 아동·가족분야를 중심으로 -)

  • Lim, JungHa;Chung, SoonHwa;Song, Jieun
    • Journal of Korean Home Economics Education Association
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    • v.28 no.2
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    • pp.61-78
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    • 2016
  • The purpose of this study was to examine the differences in terminologies used in child and family domains of family life education in South and North Korea. The terminologies relevant to child and family domains in North Korea were selected from various sources including dictionaries that are developed to compare South-North Korean languages, reports and websites by ministry of unification in South Korea, magazines and news articles about North Korean daily life. The collected terminologies were analyzed using the content criteria on core concepts, 'development' and 'relations' from the 2015 proclamation of the ministry of education on home economics curriculum. The major differences between the two Koreas were as follows: first, the terms categorized under human development were more divergent compared to the terms categorized under family relations. Specifically, there were big differences in terminologies in the love and marriage section, the life and labor in pregnancy section in human development and the child caring section in family relations. Second, dissimilar terms were more frequently appeared in content area of kinship, marriage, and child-rearing. Third, the discrepancies of terms between the two Koreas were brought about primarily by differences in political and social system, language refinement, and transcription techniques. These findings including the terminology list would be a practical resources providing for students to familiarize with the differences in the usage of terms and for teachers to develop a home economics educational program in provision of reunification of the Koreas.

A Study on the Inter-Relational Interpretation of Street Plant Issues - Focus on Central Park Road in Incheon Metropolitan City - (가로수관련 문제유형의 관계론적 해석 - 인천광역시 중앙공원길을 중심으로 -)

  • Hong, Youn-Soon;Chung, Doo-Yong;Choi, Kang-Rim
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.1
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    • pp.80-89
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    • 2008
  • Generally, trees lining the streets are the most easily accessible green areas in the city and constitute the smallest basic unit in the formation of the urban linear green axis. This study attempts to interpret issues related to city trees from a comprehensive and relational viewpoint. The site of this study is Central Park Street in front of Incheon Metropolitan City Hall. This street is representative of those in Incheon City. This study is an inter-relational interpretation of issues by measuring the vitality of these trees. The following are results of this study: First, the vitality of city trees is higher in those trees growing in natural ground than those growing in plant gratings. This observation can lead to budget savings and increased natural areas in the city. Also, if planter and multi-layering planting methods are introduced where damage to trees is predicted, variation to urban landscape can be achieved while linking to reinforced rearing foundation of street-side trees. Second, there is need for a holistic approach to caring for street-side trees regarding the damage caused by drastic pruning and strong street lights. The typical functions of these trees, like supplying freshness in summer, absorbing solar radiation, and controlling the urban micro-climate are closely related to the vitality of the trees. Accordingly, the function and ecology should be understood holistically, not separately. In this aspect, the functional and ecological use of the multi-layering planting method is effective in protecting pedestrians from vehicles as well. Third, the fallen leaves of monotonous rows of trees have different ecological and functional effects. Not only is the index of greenness in the urban setting increased, but there are also aesthetic and symbolic effects. Fourth, in spite of being the street along which Incheon Metropolitan City Hall, major administrative buildings and Central Park are located, this street does not have its own special identity to discriminate it from other streets. It fulfills only functional criteria based on uniformity. If there is no paradigm shift from today's street system based on vehicles, the role of landscape architecture will be very passive in regards to street-side trees, the minimum unit of urban green. Fifth, on this particular street, many trees were planted in December, which reflects a deficiency of short and long-term strategy, like a street-tree master plan. In this aspect, we still lack a mature culture concerning these trees as a basic unit in urban greenery. Furthermore, there needs to be cultural introspection concerning present administrative practices.

Analysis on Ventilation Efficiency of Standard Duck House using Computational Fluid Dynamics (전산유체역학을 이용한 표준 오리사 설계안에 대한 환기효율성 분석)

  • Yeo, Uk-Hyeon;Jo, Ye-Seul;Kwon, Kyeong-Seok;Ha, Tae-Hwan;Park, Se-Jun;Kim, Rack-Woo;Lee, Sang-Yeon;Lee, Seung-No;Lee, In-Bok;Seo, Il-Hwan
    • Journal of The Korean Society of Agricultural Engineers
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    • v.57 no.5
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    • pp.51-60
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    • 2015
  • In Korea, 69.4 % of duck farms had utilized conventional plastic greenhouses. In this facilities, there are difficulties in controlling indoor environments for raising duck. High rearing density in duct farms also made the environmental control difficult resulting in getting more stressed making their immune system weaker. Therefore, a facility is needed to having structurally enough solidity and high efficiency on the environmental control. So, new design plans of duck house have recently been conducted by National Institute of Animal Science in Korea. As a study in advance to establish standard, computational fluid dynamics (CFD) was used to estimate the aerodynamic problems according to the designs by means of overall and regional ventilation efficiencies quantitatively and qualitatively. Tracer gas decay (TGD) method was used to calculate ventilation rate according to the structural characteristics of duck houses including installation of indoor circulation fan. The results showed that natural ventilation rate was averagely 164 % higher than typically designed ventilation rate, 1 AER ($min^{-1}$). Meanwhile, mechanically ventilated duck houses made 81.2 % of summer ventilation rate requirement. Therefore, it is urgent to develop a new duck house considering more structural safety as well as higher efficiency of environmental control.