• Title, Summary, Keyword: 발달단계

Search Result 1,413, Processing Time 0.038 seconds

Effect of food concentration on grazing, growth and fecundity of cyclopoid copepod Paracyclopina nana (기수산 요각류 Paracyclopina nana 의 섭식, 성장 및 생산력에 관한 먹이농도의 영향)

  • Lee, Kyun-Woo;Kang, Jung-Hoon;Park, Heum Gi
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.13 no.11
    • /
    • pp.5206-5210
    • /
    • 2012
  • We studied the effect of food concentration on grazing, growth and fecundity of cyclopoid copepod Paracyclopina nana. Marine phytoplankton Tetraselmis suecica was used as a livefood for the copepod. Six stage compositions were used and food concentrations for the experiment were 0.5, 1, 2, 5, 10, 20, 40, 60 and $80{\times}10^4$ cells/mL. Range of food concentrations with 0.2, 0.5, 1, 2, 3 and $4{\times}10^4$ cells/mL were used for nauplii production experiment. Grazing rates of P. nana in all developmental stages on the different concentrations were increased with increasing diet concentration. While the growth of nauplius was not affected by increase of food concentration, food concentration outside of $1{\times}10^4$ to $5{\times}10^4$ cells/mL range negatively affected that of copepodite. Daily nauplii production was increased with increasing food concentration but $3{\times}10^4$ and $4{\times}10^4$ cells/mL treatments were not significantly different with $2{\times}10^4$ cells/mL treatment. As a result, optimum concentration of T. suecica for mass culture of P. nana was considered to be 5,000 cells/mL for nauplius stage, 10,000 cells/mL for copepodite stage and adult male, 20,000 cells/mL for adult female, respectively.

Geometrical Interpretation on the Development Sequence and the Movement Sense of Fractures in the Cheongsong Granite, Gilan-myeon Area, Uiseong Block of Gyeongsang Basin, Korea (경상분지 의성지괴 길안면지역에서 청송화강암의 단열 발달사 및 운동성에 대한 기하학적 해석)

  • Kang, Ji-Hoon;Ryoo, Chung-Ryul
    • The Journal of the Petrological Society of Korea
    • /
    • v.15 no.4
    • /
    • pp.180-193
    • /
    • 2006
  • The Gilan area in the central-northern part of Uiseong Block of Cretaceous Gyeongsang Basin is composed of Precambrian metamorphic rocks, Triassic Cheongsong granite, Early Cretaceous Hayans Group, and Late Cretaceous-Paleocene igneous rocks. In this area, the faults of various directions are developed: Oksan fault of $NS{\sim}NNW$ trend, Gilan fault of NW trend, Hwanghaksan fault of WNW trend, and Imbongsan fault of EW trend. Several fracture sets with various geometric indicators, which determine their relative timing (sequence and coexistence relationships) and shear sense, we well observed in the Cheongsong granite, the basement of Gyeongsang Basin. The aim of this study is to determine the development sequence of extension fractures and the movement sense of shear fractures in the Gitan area on the basis of detailed analysis of their geometric indicators (connection, termination, intersection patterns, and cross-cutting relations). This study suggests that the fracture system of the Gilan area was formed at least through seven different fracturing events, named as Pre-Dn to Dn +5 phases. The orientations of fracture sets show (W) NW, NNW, NNE, EW, NE in descending order of frequency. The orientation and frequency patterns are concordant with those of faults around and in the Gilan area on a geological map scale. The development sequence and movement sense of fracture sets are summarized as follows. (1) Pre-Dn phase: extension fracturing event of $NS{\sim}NNW$ and/or $WNW{\sim}ENE$ trend. The joint sets of $NS{\sim}NNW$ trend and of $WNW{\sim}ENE$ trend underwent the reactivation histories of sinistral ${\rightarrow}$dextral${\rightarrow}$sinistral shearing and of (dextral${\rightarrow}$) sinistral shearing with the change of stress field afterward, respectively. (2) Dn phase: that of NW trend. The joint set experienced the reactivations of sinistral${\rightarrow}$dextral shearing. (3) Dn + 1 phase: that of $NNE{\sim}NE$ trend. The joint set was reactivated as a sinistral shear fracture afterward. (4) Dn +2 phase: that of $ENE{\sim}EW$ trend. (5) Dn +3 phase: that of $WNW{\sim}NW$ trend. (6) Dn+4 phase: that of NNW trend. The joint set underwent a dextral shearing after this. (7) The last Dn +5 phase: that of NNE trend.

A suggestion for new parental roles according to children's developmental stages: The changing parental roles and practices (자녀의 발달단계에 맞는 새로운 부모역할 제안: 변화하는 부모역할 개념과 수행을 중심으로)

  • Rha, Jong-Hay
    • Korean Journal of Human Ecology
    • /
    • v.14 no.3
    • /
    • pp.411-421
    • /
    • 2005
  • This current study was designed to explore the meaning of being a mother and a father in contemporary Korean society by examining their roles perceived by mothers and fathers with children at different developmental stages. A total of three hundred and ninety four couples with children aged from one to seventeen years were recruited for the study, and they were asked to complete a set of questionnaires about paternal and maternal roles each. A modified version of Generative Fathering Scales by Lee et al.(1999), was used to measure the roles perceived by fathers and mothers in two areas: (1) parenting responsibilities and (2) involvement in childrearing practices. The parental roles, as expected, were viewed differently by the surveyees with children at different ages: the younger child/ren a father has, the more involvement he emphasizes in childrearing. These results indicate that the roles of mothers and fathers should be considered in the context of developing children.

  • PDF

Father-son Communication Across the Developmental Stages (발달단계에 따른 아버지와 아들의 의사소통)

  • Yeo, Chin-Kyeong;Chun, Young-Ju
    • Journal of Korean Home Management Association
    • /
    • v.25 no.1
    • /
    • pp.15-27
    • /
    • 2007
  • This study examined the relationships between father and son through son's developmental stages focusing on the father-son communication. The researcher conducted the survey among 600 male students including the 5th grade elementary students, the 2nd grade middle school students and the 2nd grade high school students residing new areas of town Pusan. The results of this study are as follows. It showed that there are some differences in function and content of father-son communication. Also it develomental stages was revealed that there is the quality differences in father-son communication through son's develomental stages. Elementary students was higher levels of father-son communication quality than those of middle and high schools. In conclusion, the results of this study showed that the relationship between father and son is changing through son's developmental stages. If father can recognize the characteristics of the developmental stages of their son's, they would be more effectively cope their sons' development demand.