• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2002.05a
• /
• pp.474-475
• /
• 2002

• Korean Journal of Social Welfare
• /
• v.31
• /
• pp.87-118
• /
• 1997

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.28 no.3
• /
• pp.237-246
• /
• 1995

Larvae of the freshwater shrimp, Macrobrachium nipponense were reared in the laboratory at constant condition $(25^{\circ}C,\;7\%o)$, and their feeding rate, oxygen consumption rate, and growth rate were measured in regular intervals of time during larval development. Regression equations describing rates of feeding, growth and respiration as functions of time during individual larval molt cycles were inserted in a simulation model in order to analyse time-dependent patterns of variation as well as in bioenergetic efficiencies. Absolute values for feeding, growth, respiration and assimilation showed clear changes during the molt cycle, The absolute and specific values of respiration (R: R/C) showed small variation during the individual molt cycles. Significance of respiration in relation to growth (G) increased within the carbon budget, respiration rate (R/C) outbalanced growth rate (G/C) in late premolt. When the portion of metabolizable carbon is respired (R/G), metabolic coefficient was < 1 (i.e. R$(K_2)$ decreased concurrently, In cumulative carbon budget, total feeding was $491.54\;{\mu}g$ C/ind., assimilation was $85.3\%$, respiration was $47.7\%$, and growth was $37.6\%$ from hatching to postlarval stage.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.27 no.4
• /
• pp.380-389
• /
• 1994

Larvae of the freshwater shrimp, Macrobrachium nipponense(De Haan) were reared in the laboratory under constant conditions ($25^{\circ}C,\;7\%0$ S), and their feeding rate, oxygen consumption, ammonia nitrogen excretion, and growth were measured at regular intervals during development from hatching to post larval stage. Growth was measured as dry weight, carbon, nitrogen, hydrogen, protein and lipid. All these physiological and biochemical traits revealed significant changes from instar to instar. Average feeding rate was high in intermolt stage of the molt cycle and it showed a bell-shaped pattern. Respiration(R) increased from hatching to post larval stage. Excretion(U) increased in intermolt phase of larvae and it showed a bell-shaped variation pattern, in all larval instars with a maximum near the middle of the molt cycle. Regression equations describing rates of feeding, growth, respiration and ammonia excretion as functions of time during individual larval molt cycles were inserted in a simulation model, in order to analyse time-dependent patterns of variation as well as in bioenergetic efficiencies. Carbon was initially increased and nitrogen showed a tendency to increase in premolt phase during individual molt cycles. Protein remained clearly the predominant biochemical constituent in larval biomass.

• Korean Journal of Social Welfare Studies
• /
• v.44 no.3
• /
• pp.301-322
• /
• 2013

By analyzing wave 1~11 (1998~2008) of Korean Labor and Income Panel Study(KLIPS) database, this study examines the effects of household characteristics and poverty duration on poverty exit. A special concern is to decide whether the decrease of poverty exit rates comes from true duration dependency or from the sample heterogeneity as poverty duration progresses. I also analyzed how the effects of independent variables are changed when unobserved heterogeneity is controlled. The results show that duration dependency disappears after controlling observed household characteristics and unobserved individual heterogeneity. This finding confirms that the apparent relationship between poverty exit rate and poverty duration is in fact a spurious association due to the sample heterogeneity rather than true duration dependency. In addition, the effects of household characteristics on poverty exit rate become more stronger when unobserved heterogeneity is controlled. Socioeconomic factors affecting poverty exit rates are such as householders' age, education, household composition, number of family members, labor force participation, and work status.

• Korean Journal of Food Science and Technology
• /
• v.16 no.3
• /
• pp.329-335
• /
• 1984

The effect of peeling methods, spherecity and weight of potatoes and carrots on the peeling efficiency were investigated. The changes in the surface texture by peeling were estimated by Rheometer and were related to the changes in the microstructure. The optimum mechanical peeling conditions using abrasion type rotary peeler were 90 sec. at 300 rpm for potatoes, 70 sec. at 300 rpm for sweet potatoes and 60 sec. at 300 rpm for carrots. The peeling loss was influenced by the sphericity and weight of the sample. The optimum conditions for alkali peeling were 90 sec. immersion in boiling 10% NaOH solution for potatoes, 300 sec. in boiling 10% NaOH solution for sweet potatoes and 60 sec. in boiling 6% NaOH solution for carrots. Severe damage of surface structure was noticed by alkali peeling, demonstrated by denaturation of starch granules in the cell. The structural damage observed by microscope was related to the reduction of cutting force after peeling.

• The Korean Journal of Zoology
• /
• v.34 no.4
• /
• pp.594-609
• /
• 1991

연안 천해에 서식하는 반부유성 갑각류인 감eomysis awatschensis를 수온 16$^{\circ}C$와 $25^{\circ}C$에서 Anemiusalina유생을 먹이로 공급하며 사육하면서 성장과 탈피에 미치는 수온의 영향을 조사, 성장, 탈피, 생식 및 호흡에 쓰인 에너지량과 체를필의 화학적 조성 및 에너지 함량을 측정한 자료로부터 개체의 사용 에너지 수지를 계산하였다. N. awatschensis 자웅의 총평균 체장성장율은 16$^{\circ}C$에서 0.08 mm/day, $25^{\circ}C$에서는 0.12maydaY였다. 수온은 동물의 각 탈피간 체장증가 백분율(growth factor)에는 영향을 미치지 않았으나 탈피기간에는 뚜렷한 영향을 나타내었다. 암컷의 체장별 각 탈피간 체장증가율은 수컷에 비하여 평균 3oye 정도 높았다. 성장과 탈피에 사용하는 평균 에너지는 각각 5.55 cal/mg X (건중, mg) 및 0.337 col/mg X (건중, mg)이였다. 난 1개의 에너지 함량은 0,057 cal이고, 암컷이 생식에 사용하는 에너지는 체장별 포란수와 관련되었다. 호흡계수는 4.5 col/ml 02였고, 회분비방법에 의한 동화효율은 70.9%였다. N. owotschensis의 총사용 에너지 중 성장에 사용하는 에너지는 갑각류의 다른 종에 비하여 높았다.

• Applied Microscopy
• /
• v.38 no.2
• /
• pp.97-105
• /
• 2008

The fine structural modification of the granulocytes between the molt and intermolt period were investigated by the transmission electron microscopy. The granular hemocytes of the spider Araneus ventricosus were composed of three subtypes: eosinophilic granulocytes (EGs), basophilic granulocytes (BGs) and cyanocytes. Both of the EGs and BGs have electron dense granules within their cytoplasms, however the granules of BGs are larger than those of EGs. During the molt period, some of the EGs have fine structural modification in their cell organelles including formation of phagosomes as a result of active phagocytosis. However, the BGs have no phagosomes, but electron densities of the granules are changed to lower states than the intermolt period. The cyanocyte is the biggest hemocyte among the granulocytes. They contain numerous hemocyanin crystals in the cytoplasm with some electron-lucent vacuoles. During the molt period, some of the cyanocytes are changed to irregular shapes. High magnification electron micrographs reveal that the lattice sub-structure of the hemocyanin crystals are very similar to those of microtubules, and each tubule is composed of approximately 20 filaments with fine fibrillar structure.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.23 no.2
• /
• pp.93-108
• /
• 1990

Complete larval development Orithyia sinica (Linnaeus) is composed of three zoeal ins-tars and megalopa. Survival of instals was higher in $20^{\circ}C$ than in ambient temperature. Intermolt period generally increased with the increase of number of instals, but a notable decrease was observed from Crab-5 to prepuerty molt instals(Crab-7). Zoeas and me-galopa reared at higher temperature regime were samller than those reared at lower temperature. No temperature effect was shown in the size of crab instals. Growth factors fluctuate with the increase of number of instals, but there was an overall trend of net decrease. Growth factor was $35.65\~41.4\%$ for zoeal instals, and they were $18.00\~30.91\%$ for crab instals.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.5
• /
• pp.207-215
• /
• 2000

This study theoretically investigated the roll-off cleanliness operation to eliminate the built-in contaminants which are primarily the result of manufacturing and assembly procedures first. A rigorous analytical examination of the cleaning process associated with hydraulic systems was performed by developing the general filtration process equations. The sloughing process by which built-in contaminant is entrained in the system fluid was examined during the development of a general analytical expression for sloughing rate. This sloughing rate expression in conjunction with the filtration process equations have lead to a relationship rate expression in conjunction with the filtration process equations have lead to a relationship which describes the flushing and clean-up operation for the hydraulic systems. The effects of the primary roll-off cleanliness factors was discussed and illustrated on the figures. Then, the analytical results was shown to be usefully applied into the design of roll-off flushing equipment for the hydraulic system of a tractor.