• Title/Summary/Keyword: Growth variation

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An Environmental Effect on Productivity of Flounder Culture Farms (넙치양식장 환경에 따른 생산성에 관한 연구)

  • Eh, Youn-Yang
    • The Journal of Fisheries Business Administration
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    • v.42 no.3
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    • pp.79-93
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    • 2011
  • Water temperature of Oliver flounder farm affects Oliver flounder growth and mortality rate. In laboratory experimental tanks, optimal water temperature was $22.5^{\circ}C$($21{\sim}24^{\circ}C$) and cultivatable water temperature was $12{\sim}28^{\circ}C$. The purpose of this study is to identify applicable and useful water temperature of Oliver flounder farm in case of actual farming. The data applied in the analysis was collected from Jeju island. In the study, various analytical methods including productivity analysis, regression analysis, statistical analysis were conducted for 13 Oliver flounder culture farms. The result of analysis can be summarized as follows : First, growth rate on the Oliver flounder culture farms was related to mean of water temperature, variation of water temperature and low water temperature. Second, survival rate on the Oliver flounder culture farms was related to mean of water temperature. In case of including Oliver flounder stocking density, defined as the surface area of Oliver flounder per $m^2$ of water surface area, survival rate strongly related to mean of water temperature, variation of water temperature, cultivating capability and stocking density. Third, production weight per $m^2$ of water surface area was strongly related to mean of water temperature, low water temperature and cultivating capability. Growth rate and survival rate was analyzed into mediate variable character.

Influence of Temperature and Relative Humidity in Infection of Nosema bombycis (Microsporidia: Nosematidae) and Cross-infection of N. mylitta on Growth and Development of Mulberry Silkworm, Bombyx mori

  • Chakrabarti, Satadal;Manna, Buddhadeb
    • International Journal of Industrial Entomology and Biomaterials
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    • v.17 no.2
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    • pp.173-180
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    • 2008
  • The influence of temperature and relative humidity in infection and cross-infection of Nosema bombycis and N. mylitta respectively in mulberry silkworm, Bombyx mori L. on larval mortality, multiplication of pathogens, larval weight and growth rate in three different seasons were studied. Seasons were selected in such condition, when very less fluctuations between minimum and maximum temperature and minimum and maximum relative humidity ($25{\sim}28^{\circ}C$ and $65{\sim}72%$ R.H) was observed i.e., season-1. Fluctuations between minimum and maximum temperature were less ($28.05{\sim}34.50^{\circ}C$) but R.H % was more ($55{\sim}81%$) in season-2. Fluctuations between minimum and maximum temperature and R.H % were more ($20.00{\sim}40.5^{\circ}C$ and $64.00{\sim}90.00%$) in season-3. Growth rate of microsporidian-infected silkworm is directly related to the prevailing temperature and relative humidity in silkworm. Silkworm can tolerate slight variation of temperature but slight variation of relative humidity disfavours the development of silkworm and favours the multiplication of pathogens.

Variation in Physiological Energetics of the Ark Shell Scapharca broughtonii (Bivalvia: Arcidae) from Gamak Bay, South Coast of Korea

  • Shin, Yun-Kyung;Choi, Yoon-Seok;Kim, Eung-Oh;Sohn, Sang-Gyu
    • Fisheries and Aquatic Sciences
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    • v.12 no.4
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    • pp.331-338
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    • 2009
  • This study presents physiological rates of respiration and excretion, clearance rate, and assimilation efficiency of the ark shell Scapharca broughtonii, determined during 2007 from specimens collected in Gamak Bay on the south coast of Korea. Physiological parameters were measured monthly under static, laboratory controlled conditions with ambient conditions, and measurements were performed seasonally in order to estimate scope for growth and its probable sources of variation. Temperature directly influenced respiration and excretion. Clearance rates showed a tendency to be low during May-August, which is a period of gametogenesis. Assimilation efficiency was not significantly different seasonally and was independent of the concentration of chlorophyll a. The scope for growth was negative during high-temperature months (July-August), reflecting the high temperature and low clearance rate, and had its highest positive values during spring and autumn. The energy budget or growth potential of bivalves has been applied to other economically important species. Data on the physiological parameters and scope for growth of S. broughtonii obtained in this study will be used to assess the carrying capacity for ark shell cultivation.

Association of Blood Pressure with Sodium and Potassium Intake for Adolescents (Sodium, Potassium 섭취와 성장기 혈압과의 관계)

  • Choi, Yoon-Sun;Kim, Young-Ok;Suh, Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.4
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    • pp.493-501
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    • 1995
  • To investigate an effect of dietary sodium and potassium on blood pressure, 418 adolescents living in Kangwha area were studied. Two measurements were taken on each blood pressure(diastolic, systolic) and the average of the two readings was used in the analysis. Sodium and potassium intake were estimated by the determination of those electrolytes in 24hr urine. Not only dietary factors but also physical growth factors such as weight, height, arm-circumference and skinfold-thickness were induced in the stepwise multiple regression analysis to indentify the relative importance between the factors. The variation of blood pressure both in systolic and diastolic in both sexes was inconsistent with the levels of sodium and potassium intake. The results of multiple regression analysis showed that the physical growth were more influential than nutrient factor. It suggested that hypertension risk factors observed form the adults, may not be identical with that of the growing aged population. After control of the physical growth, there was no significant variation observed by the level of sodium and potassium intake on blood pressure. In summary, the results indicate that growth has been more influential than dietary factor on blood pressure for growing aged population.

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A Study on Somatometric Characteristics of the Tween Generation Girls (트윈세대 여학생의 체형특성 연구)

  • Kook, Youngji;Kim, Sora
    • Journal of Fashion Business
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    • v.19 no.2
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    • pp.1-22
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    • 2015
  • This study provides the basic data for clothing construction of teen girls by researching and analyzing the characteristics of physical changes of tween generation school girls between 8 to 14 age. Fifty eight items of direct measurements and 61 calculated-items based on the 6th Korean National Physical Standard Reports were used. Results were obtained by using ANOVA, SNK test, coefficient of variation and growth rate of age groups. Significant differences were found among all the age groups, and were in the increasing order of height > length > width > depth > circumference. The growth rate was found in the increasing order of bust depth > hip width > N.P. to B.P. > hip circumference > bust circumference and thigh circumference. There were dramatic increases in height, circumference and width during the age of 8~9 and 10~11, in length during age of 10~11, and in depth during age of 8~11. The growth of the vertical measurement items is slowing at the age of 13. The individual differences were great in the vertical measurements at the age of 8 and 9 and in the horizontal measurements, at the age of 10. The increasing growth of bust and hip than waist gave it a curved shape.

Variation of the Regenerated Plantlets from in Vitro Culture of Neoregeria carorinae 'Tricolor' and in Vivo Growth of Regenerated Plantlets (네오레게리아 기내배양시 변이발생과 기외 생육)

  • 정향영;한봉희;신학기;김의영
    • Korean Journal of Plant Tissue Culture
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    • v.22 no.5
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    • pp.273-276
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    • 1995
  • In vitro propagation of Neoregeria carorinae 'Tricolor' was achieved by using immature flowers and lateral buds, and the plantlets from tissue culture were transplanted and cultivated in greenhouse. The picking times of explants to decrease disappearance of stripes, and in vivo the growth and flowering of regenerated plantlets as influenced by in vivo healed nun were investigated. The normal plantlet were obtained at a frequency of 67%, in the culture of immature flowers picked at 4 weeks after flower bud differentiation, while all leaf stripes disappeared in the culture of immature flowers picked 1 and 5 weeks after flower bud differentiation. In vivo growth of plantlet from immature flower buds was better than those from lateral buds, and the flowering of 27.8% showed in the greenhouse culture of plantlet from immature culture, but the plantlets from lateral buds did not flower at all. The plantlets rooted on the medium with 0.5 mg/L IBA were the most favorable in green house culture, and the kinds and concentrations of auxin in vitro did not have any influence on variation of plane cultured in greenhouse.

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Nucleation and Growth of Diamond in High Pressure

  • Choi, Jun-Youp;Park, Jong-Ku;Kang, Suk-Joong L.;Kwang, Yong-Eun
    • The Korean Journal of Ceramics
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    • v.2 no.4
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    • pp.221-225
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    • 1996
  • In diamond synthesis by metal film growth method under high pressure and high temperature, the nucleation and growth of diamond was observed dependent on the carbon source variation from graphite powder to the heat treated powders of lamp black carbon. At the low driving force condition near equilibrium pressure and temperature line, nucleation of diamond did not occur but growth of seed diamond appeared in the synthesis from lamp black carbon while both nucleation and growth of diamond took place in the synthesis from graphite. Growth morphology change of diamond occurred from cubo-octahedron to octahedron in the synthesis from graphite but very irregular growth of seed diamond occurred in the synthesis from lamp block carbon. Lamp black carbon transformed to recrystallized graphite first and very nucleation of diamond was observed on the recrystallized graphite surface. Growth morphology of diamond on the recrystallized graphite was clear cubo-octahedron even at higher pressure departure condition from equilibrium pressure and temperature line.

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Relation Between the Growth Twin and the Morphology of a Czochralski Silicon Single Crystal (초크랄스키 실리콘 단결정에서 성장 쌍정과 결정 외형의 관계)

  • 박봉모
    • Korean Journal of Crystallography
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    • v.11 no.4
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    • pp.207-211
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    • 2000
  • In a Czochralski silicon single crystal, the relation between the growth twin and the crystal morphology was investigated. The growth twin is nucleated on the {111} facet planes near the growth ridges. When a {111} growth twin is formed in the <100> silicon crystal, the growth ridge where twin is nucleated will continuous through the twin plane. Other two ridges at the 90。 apart will be displaced about 33° and be deformed to facets. The ridge on the opposite side of twin nucleation will disappear by forming a slight hill. Because the growth ridges of silicon is due to the {111} planes, the variation in the growth ridge formation can be predicted clearly by considering the change of the {111} plane traces in the stereographic projection after twining.

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A Study on the Influence Residual Stresses on Fatigue Crack Growth Behaviors in the Butt Welded Plate (Butt 용접판재에서의 피로균열성장거동에 미치는 잔류응력의 영향에 관한 연구)

  • 차용훈;정종안;채경수;김하식
    • Journal of the Korean Society of Safety
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    • v.8 no.2
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    • pp.64-71
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    • 1993
  • In this study, the purpose is to investigate the influence of initial residual stresses on the fatigue crack growth behaviors after the distribution of initial residual stresses Is measured when the crack is growing from the compressive residual stresses field to the tensile residual stress field. Also, the Influence of the variation of residual stress distribution on the fatigue crack growth behaviors at the crack tip is studied when the initial crack li applied on base metal, weld metal and HAZ respectively.

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Simulation of Stress Corrosion Crack Growth in Steam Generator Tubes (증기발생기 전열관에서의 응력부식균열 성장해석)

  • 신규인;박재학;김흥덕;정한섭
    • Journal of the Korean Society of Safety
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    • v.15 no.3
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    • pp.57-65
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    • 2000
  • The stress corrosion crack growth is simulated assuming a small axial surface crack inside a S/G tube. Internal pressure and residual stresses are considered as applied forces. Stress intensity factors along crack front, variation of crack shape and crack growth rate are obtained and discussed. It is noted that the aspect ratio of the crack is not depend on the initial crack shape but depend on the residual stress distribution.

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