• Asian Journal of Turfgrass Science
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• v.3 no.2
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• pp.83-88
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• 1989

This Study was designed to know the growth Status under various photoperiod using Zoysia matrella. The experimental plots were split into such groups as control (full sunlight) 3hour, 6hour and 9hour photoperiod by three replication of completely randomized design. Chlorophyll content was analyized by mackine method and total soluble sugar by anthrone method. The result obtained from this experiment was as fol1 lows ; l. Dry weight was high in the control and 9hour plots. Its decrease remarkably occured in the short day plots 2. Leaf growth woes remarkaly decreased by short day condition. Six hour was considered as critical duration for leaf growth. 3. The growth of rhizome in the 9hour and control plots was good. New development of rhizome in the' short day plots was very slow compare to the control plot. 4. Chlorophyll content was high at l8 days after transplanting and then decreased. Its content in the short day plots severely decreased. 5. The content of soluble sugar in the control was low at early growth stage and high at late growth stage. It was found that the shorter the exposure time to sunlight, the higher the ratio of sugar content.

• Journal of Bio-Environment Control
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• v.7 no.2
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• pp.109-115
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• 1998

This study was conducted to evaluate the growth and flowering responses of Eustoma grandiflorum cv. Azmasul, Azmahoon and Azmazo influenced by duration of storage at 1$0^{\circ}C$ of seedlings raised in warm season. The plants after cold treatment were cultivated in a glasshouse under natural day length with the minimum temperature of 12$^{\circ}C$. The stem thickness and number of leaves of Azmasul and Azmahoon were not affected by duration of cold treatment However, plant height, internode length fresh and. dry weights were significantly increased in the four-week treatment. In addition, four-week treatment increased flower weight and width. Bays to flowering of Azmasul and Azmahoon in four-week treatment were shortened by 20 days compared to the control or two-week treatment. Shoot growth and flower Qualify of Azmazo under the four-week treatment were promoted. Four-week treatment reduced the days to flowering of Azmazo by 31 and 36 days compared to the control and two-week treatment. The results of this study show that optimum duration for storage at l$0^{\circ}C$ for seedlings of Ewtoma grandiflorum cv Azmasul. Azmahoon and Azmazo grown in warm season is four weeks.

• Journal of Korea Water Resources Association
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• v.38 no.9 s.158
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• pp.771-778
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• 2005

In this study, flow duration analysis was conducted at the Gumbo stage gauging station due to construction of the Youngchun dam. The flow duration characteristics were $10.49\;m^3/s$ of drought flow, $13.30\;m^3/s$. of low flow, $15.65\;m^3/s$ of normal flow, and $25.00\;m^3/s$ abundant flow before construction of Youngchun dam. But after construction of Youngchun dam, the flow duration characteristics were $2.07\;m^^3/s,\;2.89\;m^3/s,\;4.0\;m^3/s,\;9.36\;m^3/s$ and they had been deteriorated. Applying the Physical Habitat Simulation Model by Instream Flow Incremental Methodology, the Weighted Usable Area(WUA)-Discharge Curve was developed for Zacco Platypus according to the growth stages. Using the WUA-Discharge Curve, the WUA Duration Curve was developed with exceedance probability of daily flow and evaluated fish habitat conditions due to the construction of Youngchun dam. As an evaluation result, the WUA was reduced and fish habitat environment was deteriorated due to the construction of Youngchun dam during the spawning and growth period of Zacco Platypus. However the exceedence probability of the $90\;\%$, irrigation water supply from the Youngchun dam improved flow duration characteristics and Weighted Usable Area as well as fish habitat.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.458-463
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• 2019

Palladium (Pd) is widely used as a catalyst and noxious gas sensing materials. Especially, various researches of Pd based hydrogen gas sensor have been studied due to the noble property, Pd can be adsorbed hydrogen up to 900 times its own volume. In this study, palladium oxide (PdO) nanostructures were grown on Si substrate ($SiO_2(300nm)/Si$) for 3 to 5 hours at $230^{\circ}C{\sim}440^{\circ}C$ using thermal chemical vapor deposition system. Pd powder (source material) was vaporized at $950^{\circ}C$ and high purity Ar gas (carrier gas) was flown with the 200 sccm. The surface morphology of as-grown PdO nanostructures were characterized by field-emission scanning electron microscopy(FE-SEM). The crystallographic properties were confirmed by Raman spectroscopy. As the results, the as-grown nanostructures exhibit PdO phase. The nano-cube structures of PdO were synthesized at specific substrate temperatures and specific growth duration. Especially, PdO nano-cube structrures were uniformly grown at $370^{\circ}C$ for growth duration of 5 hours. The PdO nano-cube structures are attributed to vapor-liquid-solid process. The nano-cube structures of PdO on graphene nanosheet can be applied to fabricate of high sensitivity hydrogen gas sensor.

• Management Science and Financial Engineering
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• v.16 no.3
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• pp.49-70
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• 2010

Customer population management models can be classified into three categories: the first category includes the models that analyze the customer population at cohort level; the second one deals with the customer population at aggregate level; the third one has interest in the interactions among the customer populations in the competitive market. Our study proposes a model that can analyze the dynamics of customer population in consumer-durables market at aggregate level. The dynamics of customer population includes the retention curves from the purchase or at a specific duration time, the duration time expectancy at a specific duration time, and customer population growth or decline including net replacement rate, intrinsic rate of increase, and the generation time of customer population. For this study, we adopt mathematical ecology models, redefine them, and restructure interdisciplinary models to analyze the dynamics of customer population at aggregate level. We use the data of previous research on dynamic customer population management at cohort level to compare its results with those of ours and to demonstrate the useful analytical effects which the precious research cannot provide for marketers.

• Journal of Photoscience
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• v.10 no.1
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• pp.157-164
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• 2003

Light exerts two primary roles in plant growth and development. Plants acquire all biochemical energy required for growth and propagation solely from light energy via photosynthesis. In addition, light serves as a medium through which plants recognize environmental fluctuations, such as photoperiod and presence of neighboring animals and plants. Plants therefore constantly monitor the direction, intensity, duration, and wavelength of environmental light and integrate these light signals into the intrinsic regulatory programs to achieve an optimized growth in a given light condition. Although light regulates all aspects of plant growth and developmental aspects, the molecular mechanisms and signaling cascades involved have not been well established until recently. However, recent advances in genetic tools and plant transformation techniques greatly facilitated the elucidation of molecular events in plant photomorphogenesis. This mini-review summarizes the gist of recent findings in deetiolation and suppression of shade avoidance response as classic examples of the phytochrome-mediated photomorphogenesis.

• Journal of the Korean Society of School Health
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• v.30 no.3
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• pp.317-324
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• 2017

Purpose: Breakfast is the most important meal to provide energy for the day. Breakfast is especially important to give enough nutritional support to children and adolescents for their physical growth and sexual development. Sleep-related factors like average sleep duration and wake up time would mostly be associated with regular breakfast. This study aimed to investigate the effect of sleep on regular breakfast consumption in Korean adolescents. Methods: The study used the data from the 12th Korea Youth Risk Behavior Web-based Survey (KYRBS-XII) conducted in 2016 by the Korea Centers for Disease Control and Prevention. The data of 62,820 subjects (middle/high school students) were included in the final analysis. The study examined the factors related to regular breakfast, focusing on weekday average sleep duration and wake up time of middle school students and high school students, respectively. Results: Regular breakfast consumption was shown to have a statistically significant association with high economic status, nutritional education, weekday average sleep duration, wake up time, and subjective sleep satisfaction in the multivariate logistic regression. Regardless of the school level, regular breakfast consumption was significantly associated with early wake up time. As to the effect of weekday average sleep duration on regular breakfast consumption, it showed some different results depending on the school level. Conclusion: Regular breakfast consumption of Korean adolescents was related to weekday average sleep duration and wake up time. Having breakfast regularly was affected by both adequate weekday average sleep duration and early wake up time.

• Journal of the Korean Society of Tobacco Science
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• v.11 no.1
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• pp.27-39
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• 1989

This study was conducted to determine the time and methods of predicting tobacco yield. by analysis of climatic factors in the period of tobacco season during 8 years from 1979 to 1986 at the Daegu district, south eastern part of Korean peninsular. The results obtained are summarised as follows: 1. Climatic factors of each month which have influence on tobacco yield were the amount of rainfall in May and sunshine hours in July. Among climatic factors at tobacco growth stages, the precipitation yield. But these meteorological factors had different effect on variety. 2. Between tobacco yields and climatic factors by even values of each month, tobacco yield was estimated by equations, flue cured tobacco :Y=190.6-5.230X1+ 0.474$\times$2 + 0.142X3(Xl : Minimum temperature of April, X2: Precipitation during May, X3:Sunshine duration on July), air cured tobacco : Y= 195.3-0.447Xl + 0.363$\times$2 + 0.l12$\times$3(Xl :Maximum temperature of May, X2:Precipitation during May. X3: Sunshine duration on July). While between tobacco yield and climatic factors at different growth stage, predicting equation of yield could be derived, flue cured tobacco : Y=205.8+0.510Xl +0.289$\times$2 + 0.305$\times$3 (Xl :Average temperature during the early growth stage, X2 :Precipitation during the early and maximum growth stage, X3 : Sunshine hours during the leaf and tips maturing stage), air cured tobacco Y=194.T-0.498Xl 10.615$\times$2+0.121$\times$3(Xl ;Maximum temperature during the transplanting time, X2 : Precipitation during the maximum growth stage, X3 : Sunshine hours during the leaf and tips maturing stage).

• Journal of Chest Surgery
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• v.6 no.1
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• pp.15-22
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• 1973

The definition of cancer, its diagnosis and its prognosis all depend upon description of growth. To the layman a synonym for cancer is a "growth". There are no quantitative terms for the description of growth or growth rate in clinical use. There has been no attempt to assign values that would define "rapidly" or "slowly" growing. Estimates of growth potentiality are implied in the descriptive phrases "poorly differentiated" or "well differentiated", "highly malignant" or "low grade malignancy". and in systems of grading. These qualifying terms represent a personal impression, clinically useful in prognosis, but relative in nature. They do not lend themselves to uniform application or precise measurement for purpose of comparison. Growth is related to size and time. The volume of tumor depends upon the duration of the period of growth and the rate of growth. If the interval and change in volume are known. the average growth rate can be determined. If the growth rate is determined, and assumed to be constant., the duration of a given tumor and the time of inception can be estimated. The commonest concept of the origin of cancer is that as a result of a mutation involving a single cell, succeeding divisions of cells establish a colony with the characteristics recognizable as cancer. If the growth rate of the hypothetical tumor were constant it could be described in terms of "tumor volume doubling time". In the department of thoracic surgery of St. Mary hospital in Catholic Medical College, a clinical evaluation for the growth rate, degree of malignancy, resectability and prognosis was done on a total 24 cases of primary bronchogenic carcinoma which contour was significant on the chest X-ray film as possible estimating the tumor volume doubling time. The following results were obtained: 1. In the cases of 6.0cm or more in diameter of minor size at operation the resectability rate was lower and in the cases of 60 days or more in the tumor or volume doubling time the resectability rate was higher. 2. If differentiation of cancer cells was lower graded in tissue pathology, the tumor volume was shorter and the resectability rate was lower. 3. The tumor volume doubling time of the primary bronchogenic carcinoma occured more over 60 years of age was slightly shorter than under 60 years of age. 4. The tumor size at operation was more important to evaluate the survival time and prognosis than the tumor volume doubling time because the tumor growth was not always constant, we presume.mor volume doubling time because the tumor growth was not always constant, we presume.

• Journal of Preventive Medicine and Public Health
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• v.56 no.4
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• pp.338-347
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• 2023

Objectives: Young children's feeding characteristics can play an important role in eating habits and health during later childhood. This study was conducted to examine the associations of feeding characteristics with dietary patterns and obesity in children. Methods: This study utilized data from the Korea National Health and Nutrition Examination Survey conducted between 2013 and 2017. In total, 802 toddlers were included, with information on their demographic characteristics, feeding practices and duration, and 24-hour recall obtained from their parents. Feeding characteristics were categorized into feeding type, duration of total breastfeeding, duration of total formula feeding, duration of exclusive breastfeeding, and age when starting formula feeding. Dietary patterns were identified based on factor loadings for the food groups for 3 major factors, with "vegetables & traditional," "fish & carbohydrates," and "sweet & fat" patterns. Overweight/obesity was defined as ≥85th percentile in body mass index based on the 2017 Korean National Growth charts for children and adolescents. Multiple regression analysis was conducted to examine associations between feeding characteristics and dietary patterns. The association between dietary patterns and obesity was analyzed using multivariable logistic regression analysis. Results: The early introduction of formula feeding was inversely associated with the "vegetables & traditional" pattern (β=-0.18; 95% confidence interval [CI], -0.34 to -0.02). A higher "vegetables & traditional" intake was associated with a lower risk of obesity (odds ratio, 0.48; 95% CI, 0.24 to 0.95). Conclusions: Feeding characteristics are associated with dietary patterns in later childhood, and dietary patterns were shown to have a potential protective association against obesity.