• Journal of Nutrition and Health
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• v.32 no.2
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• pp.182-188
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• 1999

A study was conducted on a group of 107 women, attending the three peripheral community clinics in Seoul and Kyunggi area for their prenatal care, to ascertain the relationship between maternal serum zinc concentration measured in pregnancy and several pregnancy outcomes. The serum zinc concentration was adjusted for estimated gestational age at the time of drawing blood. Mean daily zinc intake of the pregnant women estimated by a 24-hour recall method was 7.68$\pm$3.70$\mu\textrm{g}$/dl, 51% of RDA. and mean serum zinc concentration of the women was 94.03$\pm$36.99ug/dl. Adjusted maternal serum zinc level was significantly related to gestational maternal weight gain(p<0.05) and infant birth weight(p<0.05). Pregnant women with tgreater than 9kg weight gain during the gestation period had higher adjusted serum zinc levels than the subjects with less than 8kg weight gain. Adjusted serum zinc levels of mothers who delivered 3.0-3.5kg and greater than 4.0kg birth-weight infants were higher than those of mothers of low-birth-weight infants. Any association between maternal serum zinc level and gestational length, complications and morning sickness was not observed. There results suggest that the maternal serum zinc level may predict perhaps the author could be none specific.

• Carbon letters
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• v.14 no.4
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• pp.197-205
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• 2013

Five vapor-grown carbon nanofiber (VGCNF) reinforced vinyl ester (VE) nanocomposite configurations were fabricated, imaged, and mechanically tested in order to obtain information on the influence and the interactions of the role of the microstructure at lower length scales on the observed continuum level properties/response. Three independent variables (the nanofiber weight fraction and two types of nanofiber mixing techniques) were chosen to be varied from low, middle, and high values at equally spaced intervals. Multiple mixing techniques were studied to gain insight into the effect of mixing on the VGCNF dispersion within the VE matrix. The point count method was used for both lower length-scale imaging techniques to provide quantitative approximations of the magnitude and the distribution of such lower length-scale features. Finally, an inverse relationship was shown to exist between the stiffness and strength properties of the resulting nanocomposites under uniaxial quasistatic compression loading.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.3
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• pp.154-160
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• 1970

The present paper deals with the growth of yellow croaker by scale age reading. This study is based on material from 596 specimens caught by the Danish seine in the Yellow Sea during the period from June 1967 to April 1968. Ring marks of the scale were formed from April to July, corresponding to the spawning season of the fish reported by Bae (1960). Growth rate of each radius of the ring was approximately 0.73. The relationship between the total length and radius of scales, and the relationship between the body weight and total length are represented by the following equations respectively: L=61.350R+50.184 $$W=4.298L^{3.227}\times10^{-3}$$ Maximum total length calculated by the diagram of Walford's growth transformation, $$L_{n+1}=0.6866L_n+10.8730$$, was 346.9mm. Growth curve of the fish can be expressed by the following von Bertalanffy's equation : $$L_t=346.9(1-e^{-0.376(t+0.609)})$$

• Journal of the Korean Home Economics Association
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• v.40 no.10
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• pp.231-241
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• 2002

This study is for research of relationship between shoes wearing by adult woman and foot type. The research was made through questionnaire sheets of general matters (age, body weight, height & occupation) and shoes wearing status (hill height, toe shape, wearing time) of 216 adult women reside in the metropolitan zone and the foot type was classified from foot measurement and the relationship between shoes wearing and foot type was analyzed. According to the result of analysis it is as follows : 1) In the shoes type prefer for they prefer for lower hill as more ages and were preferring shoes with higher hill as the taller women. 2) The instep height is lower and medial foot angle was increased as their ages are more. Majority of foot type was appeared with standard type and the broad type was indicated more by age of 20s. The classification by toe the square type was indicated by majority and in the age of 30-40s the egyptian type was more 3) As the age and weight get increased he height of arch become lower and indicated to transit to flat-foot. That is to say they prefer for round toe in case of fiat-foot, and for square toe in case of normal and, choice of shoe toe shape it indicated by more impact by the height of arch rather than toe length.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.5
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• pp.539-548
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• 1995

The process of yolk absorption and the growth pattern of churn salmon, Oncorhynchus keta alevin were studied. Matured males and females of chum salmon were sampled from the Namdaechun River in the east coast of Korea, and then an artificial fertilization was carried out using their eggs and sperms. Fertilized eggs were incubated in controlled water temperature of $13^{\circ}C$ and samples of 40 alevins were randomly taken at just hatching and at every three days between 12 days alter hatching and yolk absorption. The means of total length and total weight of hatched alevins were respectively 1.97cm and 1.85g and the yolk absorption took about 33 days after hatching, based on the morphological measurement. Growth curves of total length, total weight and somatic weight were fitted well with the Gompertz growth model. However, the shrinking in yolk-sac length, yolk-sac weight, yolk-sac height and yolk-sac volume revealed a linear phenomenon until the absorption of yolk was completed. The relative growth of chum salmon alevin, such as the relationship between total length and total weight, or between total weight and yolk-sac weight, was also studied.

• Journal of Biosystems Engineering
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• v.27 no.4
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• pp.283-292
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• 2002

Mechanical and physical properties of various parts of jujube (Zizyphus jojoba Miller) such as fruits, leaves, secondary branches, and leafy stems were measured and analyzed. The physical dimensions of the fruits were measured using a digital caliper, and the detachment force of the fruit and leafy stems was measured using a force gauge. The physical characteristics of the secondary branches such as the modulus of elasticity and the torsional rigidity were tested using a universal testing machine (UTM). The physical characteristics of leafy stems such as length and weight were also measured using a digital caliper and a digital scale, respectively. The detachment force of leafy stems and the area of the leaf also measured. The terminal velocities of the jujube fruits, leaves, and leafy stems were measured using a custom made terminal velocity experiment system. Diameter of the major and minor axis of the jujube fruit, weight of the fruit, and detachment force of the fruit stem was average of 32.02 mm, 23.92 mm. 10.0 ${\times}$ 10$\^$6/ ㎥, 8.99 g, and 5.43 N. respectively. The detachment forces of the jujube fruits increased and the force-to-weight ratio of the jujube fruits decreased as the weight of the jujube fruits increased. The modulus of elasticity of the secondary branches of the jujube was average of 7.01 ${\times}$ 10$\^$8/ N/㎡ and decreased as diameter of the secondary branches increased. The average torsional rigidity of the secondary jujube branches was 5.2 ${\times}$ 10$\^$-/ N/㎡, and the torsional rigidity decreased as the secondary branch diameter increased. The distribution of the torsional rigidity data associated with the diameter of the branches, however. widely scattered and it was difficult to find any relationship between the diameter of the branches and the torsional rigidity of tile branches. The weight of the leafy stems, number of loaves attached to the leafy stems, diameter of the stem side of the leafy stems, diameter of the leafy stem end was average or 0.7 g, 6.6 ea, 12.2 cm, 4.5 mm, and 2.7 mm, respectively. The major and minor axis of the .jujube loaves, area of leaves, weight of the leaves. and detachment force of the leaves was average of 5.7 cm, 3.3 cm, 12.98 cm$^2$, 0.20 g, and 4.39 N, respectively. The terminal velocity of the .jujube fruits increased as the weight of the fruits increased. The terminal velocity of the leafy stems, however, did not show a relationship with the weight of the leafy stems and the number of leaves attached to the leafy stem. The terminal velocity, however, slightly increased as the length of the leafy stems increased.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.4
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• pp.152-157
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• 2006

Samples of Meretrix lusoria were collected monthly from the tidal flat of Simpo, Puan-gun, Chollabuk-do, west coast of Korea from April 2004 to March 2005. Age of M. lusoria was determined from the rings on the shell. The relationship between shell length and ring radius in each ring group was expressed as a regression line. Therefore, there is a correspondence in each ring formation. Based on the monthly variations in the marginal index (MI') of the shell, it is assumed that the ring of this species was formed once a year during the period of February to April. The relationship between shell length (SL) and shell height (SH; mm) was highly correlated with shell height as the following equation: SH = 0.8103 SL + 0.5145 $(r^2=0.991)$. The shell length (SL) - shell width (SW) relation was also expressed by the following equation: SW = 0.4897 SL + 0.0315 $(r^2=0.976)$. Shell length (SL; mm) and total weight (TW; g) was expressed by the following equation: $TW=2.9195\times10^{-4}\;SL^{2.9547}\;(R^2=0.991)$. Shell length (SL) and shell height (SH; mm) was highly correlated with shell height as the following equation: $SH=0.8103\;SL+0.5145\;(R^2=0.991)$ The shell length (SL) - shell width (SW) relation was also expressed by the following equation: $SW=0.4897\;SL+0.0315\;(R^2=0.976)$. Growth curves for shell length and total weight fitted to the von Bertalanffy's growth curve were expressed respectively as: $SL_t=104.9[l-e^{-0.2235(t+0.7677)}],\;TW_t=280.8[l-e^{-0.2235(t+0.7677)}]^{2.9547}$.

• Korean Journal of Environment and Ecology
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• v.34 no.5
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• pp.402-412
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• 2020

This study aims to examine the population characteristics of the fish and the bluegill (Lepomis macrochirus), designated as ecologically disturbing fish, living in four water dams in the Ulsan area and to provide basic data. The survey of fish living in 4 water dams and surrounding tributaries in the Ulsan area from 2016 to 2017 found a total of 1,987 individuals of 28 species of 9 families and identified 6 Korea's endemic species is (21.4% indigenous rate), 4 exotic species, and 2 ecosystem disturbing species. Based on the number of fishes identified, the dominant species was Lepomis macrochirus, and the subdominant species was Hemiculter eigenmanni. The investigation of the age structure of the L. macrochirus found in the 4 water dams in the Ulsan area showed a large population of 1 to 2 old, and the population was growing fast. Moreover, the analysis of the total length-weight relationship and obesity of the L. macrochirus population showed that the regression coefficient b of the total length-weight relationship was greater than 3.0, and the habitat of the L. macrochirus population was in good condition. Obesity had a positive slope, and the growth state was relatively good. The result of this study can be used as useful data to predict the trend of the L. macrochirus fauna inhabiting in 4 water dams in the Ulsan area.

• Journal of Environmental Impact Assessment
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• v.23 no.2
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• pp.137-149
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• 2014

The purpose of this study is to investigate the dynamics of the Zacco platypus population among streams in the Gongjicheon water system, Korea from December 2010 to October 2011. In this study, fish fauna was collected 27 Species belonged to 9 Families. The legal protection species, such as a natural monument and endangered species was not collected. Korean endemic species was collected 6 species including to Z. koreanus. The ratio of Korean endemic species was 22.6%, and it was lower than 51.3% that average of Korean endemic species in the Hangang water system. About these status, we considered that Gongjicheon water system had lost of the unique characteristics of the Hangang water system by the anthropogenic disturbances. The result of analysis to length-weight relationship and condition factor(K) of Z. platypus population in the Gongjicheon water system, the regression coefficient value(b) to indication of growth degree of the population was 3.04 and the slope of the condition factor(K) to indication of corpulency had positive value, respectively. These results seems to be that the Z. platypus population is maintained to a little unstably. In addition, the values of the degree of growth and corpulence were very low than the other natural streams in the Hangang water system, so it considered that the many artificially stress factors are occurred in this study area. These results are similar to Fish Assessment Index(FAI) in the assessment for health of aquatic ecosystem. Therefore, we are considered to require precise investigation and sustained monitoring for the restorations of stream ecosystem in the Gongjicheon water system.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.391-399
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• 2006

The population dynamics of Zacco koreanus in the upstream and downstream of Hoengseong Lake, Korea were investigated from April to October 2005. As the result of a comparison of variations regarding the time of I koreanus populations, it was confirmed that downstream was a place to remain compared to upstream Also the b value, assessed by Length-weight relationship in upstream and downstream, were $3.21{\sim}3.35,\;and\;2.94{\sim}3.37$, respectively indicating the fish in downstream had better than upstream. Additionaly condition factor(K) of each population in upstream and downstream were $0.0292{\sim}0.0693\;and\;-0.0165{\sim}0.0499$, respectively, K value in upstream lower than downstream. On the other hand, the maximum-growth value$(L_{\infty})$ calculated by von Bertalanffy's growth model in upstream and downstream were 279.7mm and 303.9mm, respectively, indicating that the potential-growth ability of population in downstream was higher than population in upstream. Therefore, Z. koreanus population in upstream became worse based on matters of age structure, Length-weight relationship, and von Bertalanffy's growth model. These results are considered to show the change of the physical environment by the constructing of Hoengseong Dam.