• Journal of Sericultural and Entomological Science
• /
• v.32 no.1
• /
• pp.8-16
• /
• 1990

The experiment was conducted to obtain estimates of heterosis, selective index, genetic advance and selective efficiency in cross among silkworm varieties. Seven parents, 21 F$_1$ hybrids, and 21 F$_2$ populaltions from diallel crosses among them were evaluated. The results obtained are summarized as follows: In male and female of F$_1$ generation, the negative heterosis was shown in two characters of fifth instar period and boiling on ratio, and the positive heterosis with the value of 20.90-37.60% in the other characters. In those of F$_2$, the nagative heterosis was shown in two characters of cocoon layer ratio and boiling off ratio, and the positive heterosis in the other characters. The selection weight of cocoon weight for bave weight was the highest of those of all the characters, and that of the combination of the fifth instar period and cocoon weight for it was the highest of those of all the combination. The genetic advance of cocoon weight toward bave weight was the highest of all the characters. The highest genetic advance and selective efficiency were shown in the combination of all the characters.

• Neonatal Medicine
• /
• v.15 no.1
• /
• pp.38-43
• /
• 2008

Purpose : The purpose of this study was to evaluate the relationship between cord serum adiponectin (APN) and IGF-I concentrations and fetal growth. Methods : Umbilical cord serum APN and IGF-I concentrations were measured in healthy term singleton deliveries (n=72). The association of cord serum APN and IGF-I concentrations was evaluated in relation to birth weight, height, head circumference, gender, ponderal index, placental weight, feto-placental (F/P) weight ratio, maternal weight gain, and maternal body mass index (BMI). Results : The mean cord serum APN was 29.2${\pm}$10.46 $\mu$g/mL. The cord serum APN and birth weight demonstrated a bell-shape relationship. The cord serum APN concentration was higher in females than males (P=0.001). The cord serum APN was negatively correlated with maternal BMI (r=-0.301, P=0.027), but the mean cord serum APN concentration was not correlated with birth height, birth head circumference, ponderal index, placental weight, F/P ratio, or maternal weight gain. The mean cord serum concentrations of IGF-I was 51.26${\pm}$21.54 ng/mL. The cord serum IGF-I concentration was positively correlated with birth weight (r=0.312, P=0.009), but not birth height, ponderal index, placental weight, F/P weight ratio, or maternal BMI. Conclusion : APN demonstrated a bell-shaped relationship with birth weight in healthy term infants. IGF-I was highly correlated with fetal growth, especially birth weight.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.9 no.4
• /
• pp.11-20
• /
• 2009

By using the artificial lightweight aggregate for the natural aggregate depletes and destruction of environment and the application of lightweight concrete in structure, the lightweight concrete is manufactured. The fundamental characteristics by the waterbinder ratio was evaluated. It is suggested the method to control of pre-absorbed water of the lightweight aggregate. Lightweight concrete with pre-absorbed aggregate has similar characteristics compared to normal weight concrete regardless of water-binder ratio. According to the water-binder ratio, the drying condition, and the rebar, the unit mass of the lightweight concrete showed the reduction of 14.6${\sim}$21.0% as the range of 1,668${\sim}$1,998 $kg/m^3$ in comparison to the normal weight concrete. The lightweight aggregate pre-absorbed water showed the deferent evaporation quantity according to the water-binder ratio. As the water-binder ratio is lower, the oven dry vapour water is larger, therefore the internal curing water is increasing. In the same water-binder, comparing the normal concrete the lightweight concrete shows lower compressive strength which is due to the different strength of an aggregate. In the air dry curing, the normal weight concrete has a lower strength improvement effect in w/c 0.3 than the ratio 0.4 and 0.5. However, the strength improvement effect has increasing as the water-binder ratio was low in the light concrete.

• Horticultural Science & Technology
• /
• v.31 no.4
• /
• pp.393-399
• /
• 2013

The effect of solution temperature and nitrogen form on cucumber (Cucumis sativus L.) growth, photosynthesis and nitrogen metabolism was investigated in hydroponic culture. Cucumber plants were grown for 35 days in a greenhouse at three constant solution temperatures ($15^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$) within a natural aerial temperature ($15-30^{\circ}C$). Four nitrate:ammonium ($NO{_3}^-:NH{_4}^+$) ratios (10:0, 8:2, 5:5, and 2:8 $mmol{\cdot}L^{-1}$) at constant nitrogen (N) concentration of $10mmol{\cdot}L^{-1}$ were applied within each solution temperature treatment. Results showed an increasing solution temperature enhanced plant growth (height, dry weight, and leaf area) in most N treatments. Dry weight accumulation was greatest at the 10:0 $NO{_3}^-:NH{_4}^+$ ratio in the $15^{\circ}C$ solution, the 5:5 ratio in the $20^{\circ}C$ solution and the 8:2 ratio in the $25^{\circ}C$ solution. Photosynthetic rate (Pn) response to solution temperature and $NO{_3}^-:NH{_4}^+$ ratio was similar to that of plant growth. Probably, the photosynthate shortage played a role in the reduced biomass formation. Increasing solution temperature enhanced the nitrate reductase (NR) activity, and further reduced shoots nitrate content. Our results indicate that the optimal ratio of nitrate to ammonium that promotes growth in hydroponic cucumber varies with solution temperature.

• Neonatal Medicine
• /
• v.28 no.2
• /
• pp.65-71
• /
• 2021

Purpose: We investigated whether consecutive levels of new emerging renal biomarkers, including serum cystatin C (CysC) and urinary neutrophil gelatinase-associated lipocalin (NGAL)/creatinine (Cr) ratio, were affected by postconceptional age in very-low-birth-weight (VLBW) infants. Methods: Repeatedly measured samples for each infant were divided into four groups according to postnatal age: at birth (stage I), 3 to 7 days postnatally (stage II), 8 to 28 days postnatally (stage III), and >28 days postnatally (stage IV). The association between renal biomarkers and postconceptional age was assessed using Pearson's correlation coefficient, and the mean values of renal biomarkers in the four stages were compared using repeated-measures analysis of variance. Results: For samples measured at birth, serum CysC (r=-0.358, P=0.032) and urinary NGAL/Cr ratio (r=-0.522, P=0.001) were negatively correlated with gestational age, whereas serum Cr (r=0.148, P=0.390) was not. In addition, for all samples measured, serum CysC (r=-0.209, P=0.012), urinary NGAL/Cr ratio (r=-0.536, P<0.001), and serum Cr (r=-0.311, P<0.001) were negatively correlated with postconceptional age. Compared with the mean values of the postnatal age-specific stages, serum CysC showed no significant differences in any of the four stages. However, the urinary NGAL/Cr ratio in stage IV was significantly different from those in stages I to III. Conclusion: Although urinary NGAL/Cr ratio and serum CysC were negatively correlated with postconceptional age considering renal development, serum CysC showed no significant differences in any of the four postnatal age-specific stages. Urinary NGAL/Cr ratio at >28 days postnatally seems to be more affected by postconceptional age than serum CysC in VLBW infants.

• Korean Journal of Human Ecology
• /
• v.20 no.2
• /
• pp.413-426
• /
• 2011

This research was designed to compare the subjective evaluation of texture image and preference according to fiber blending ratio of men's suit fabrics. 110 subjects evaluated the texture image and preference of various fabrics. For statistical analysis, factor analysis, MDS, pearson correlation and ANOVA were used. The results were as follows: Sensory image factors of suit fabrics were 'smoothness', 'bulkiness', 'stiffness', 'elasticity', 'moistness' and 'weight sensation'. Sensibility image factors were 'classic', 'practical', 'characteristic' and 'sophisticated'. 'Bulkiness' and 'elasticity' sensory images showed high correlations with sensibility images. Fabrics with high wool blending ratio showed as 'classic' and 'sophisticated', 'bulkiness' and 'elasticity' texture images and fabrics with low wool blending ratio showed texture images of 'characteristic', 'surface character', 'stiffness', 'moistness' and 'weight sensation'. Wool fiber blending ratio affected on the purchase preference and tactile preference. Using regression analysis, it was shown that sensibility images had more of an effect on preference than sensory images. The thickness and pattern type showed positive effects and fiber blending ratio showed negative effects on the preference.

• Journal of the Korea Furniture Society
• /
• v.14 no.2
• /
• pp.31-38
• /
• 2003

This study was carried out to investigate characteristics of wood-based panels and wood-cement board for the possible uses as flooring and wall materials. The optimum cement/wood ratio(C/W ratio) of wood~cement board manufactured by clamp-pressing was from 2.7 to 3.2. The dimesional stability was superior in the C/W ratio of 3.2. Particularly, the dimensional stability of cement board using fine particle for particleboard face layer was favorable through three levels of C/W ratio. According to types of wooden material, bending strength of cement board using coarse particle for particleboard core layer or old newspaper(ONP) fiber was relatively higher than others. Thermal conductivities of wood-cement boards were no lower than that of gypsum board, and higher than those of plywood and boards. In case of wood-cement board of the C/W ratio of 2.7, the fire-proof performances of cement composite boards were greater than that of gypsum board, and weight loss reached to about a half of gypsum board. Then, wood-cement boards showed superior fire-proof performance compared to wood-based panels.

• Journal of the Korean Wood Science and Technology
• /
• v.47 no.2
• /
• pp.221-228
• /
• 2019

This study reports the performance of urea-formaldehyde (UF) resins prepared at two different low formaldehyde/urea (F/U) mole ratios with different numbers of urea addition during synthesis. The second or third urea was added during the synthesis of UF resins to obtain two different low molar ratios of 0.7 and 1.0, respectively. The molecular weights, cure kinetics, and adhesion performance of these resins were characterized by the gel permeation chromatography, differential scanning calorimetry, and tensile shear strength of plywood, respectively. When the number of urea additions and F/U molar ratio increased, the gelation time decreased, whereas the viscosity and molecular weight increased. Further, the UF resins prepared with the second urea and 1.0 molar ratio resulted in greater activation energy than those with third urea and 0.7 molar ratio. Tensile shear strength and formaldehyde emission (FE) of the plywood that bonded with these resins increased when the number of urea additions and molar ratio increased. These results suggest that the UF resins prepared with 0.7 molar ratio and third urea addition provide lower adhesion performance and FE than those resins with 1.0 mole ratio and the second urea addition.

• Advances in concrete construction
• /
• v.10 no.6
• /
• pp.527-536
• /
• 2020

In this study, a process is proposed to calculate analytical correction values for the vertical shortening of all columns on all floors in a high-rise building that minimizes the error between the structural analysis predictions and values measured during construction. The weight ratio and the most probable value were accordingly considered based on the properties of the shortening value analyzed at several points in each construction stage and the distance between these measured points and unmeasured points at which the shortening was predicted. The effective range and shortening value normalization were considered using the column grouping concept. These tools were applied to calculate the error ratio between the predicted and measured values on a floor where a measured point exists, and then determine the estimated error ratio and estimated error value for the unmeasured point using this error ratio. At points on a floor where no measured point exists, the estimated error ratio and the estimated error value were calculated by applying the most probable value considering the weight ratio for the nearest floor where measured points exist. In this manner, the error values and estimated error values can be determined at all points in a structure. Then, the analytical correction value, defined as this error or estimated error value, was applied by adding it to the predicted value. Finally, the adequacy of the proposed correction method was verified against measurements by applying the analytical corrections to all unmeasured points based on the points where the measurement exists.

• Journal of the Korea Convergence Society
• /
• v.8 no.2
• /
• pp.163-168
• /
• 2017

The feasibility evaluation of public projects has been carried out mainly in the economic analysis. However, items of political, technological and balanced regional development aspects are further evaluated by applying analytic hierarchy process, This paper suggests to analyzes preliminary feasibility study of construction and research & development project during the past three years and to verify correlation between B/C ratio and AHP weight. The result shows that the correlation between cost benefit ratio and the weight of the hierarchy is 0.744 in construction projects and 0.899 in research & development project. Namely, AHP weight be under the control of B/C ratio and is devoted to its role against expectation. Therefore it must be sufficiently discussed in various designs of studies to maximize the effects of AHP analysis.