• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.1
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• pp.1-14
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• 2021

Onions are a representative produce that requires supply-demand control measures due to large fluctuations in production and price by growing season. Accurate forecasts of crop production can improve the effectiveness of such measures. However, it is challenging to obtain accurate estimates of crop productivity for onions because they are mainly grown on the open fields. The objective of this study was to perform the empirical analysis of the relationship between factors for crop growth and meteorological conditions, which can support the development of models to predict crop growth and production. The growth survey data were collected from open fields. The survey data included the weight of above ground organs as well as that of the bulbs. The estimates of meteorological data were also compiled for the given fields. Correlation analysis between these factors was performed. The random forest was also used to compare the importance of the meteorological factors by the growth stage. Our results indicated that insolation in early March had a positive effect on the growth of the above-ground. There was a negative correlation between precipitation and the growth of the above-ground at the end of March although it has been suggested that drought can deter the growth of onion. The negative effects of precipitation and daylight hours on the growth of the above-ground and under-ground were significant during the harvest period. These meteorological factors identified by growth stage can be used to develop models for onion growth and production forecast.

• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.4
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• pp.67-77
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• 2002

This paper introduces the calibration results of the fatigue crack growth models for damage tolerance analysis of the aircraft structures. Generalized Willenborg model and Wheeler model are calibrated with experimental data tested under the load spectrum of a trainer. The retardation factors such as, shut-off ratio in Generalized Willenborg model and shaping exponent in Wheeler model, are evaluated for aluminum alloys AL2024-T3511, AL7050-T7451 and AL7075-T73511. It is shown that the retardation effect of the crack growth rate depends on the yield strength of material and the maximum stress in the load spectrum. Generalized Willenborg model and Wheeler model give satisfactory prediction of crack growth life but the calibration of the experimental parameters with test is required.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.11
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• pp.2749-2761
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• 2000

Densification, grain growth, and phase transformation of nanocrystalline ceramic powder were investigated under pressureless sintering, sinter forging, and hot pressing. A constitutive model for densification of nanocrystalline ceramic powder was proposed and implemented into a finite element program (ABAQUS). A grain growth model was also proposed by including the effect of applied stress on grain growth when phase transformation occurs. Finite element results by using the proposed models well predicted densification behavior, deformation, and grain growth of nanocrystalline titania powder during pressureless sintering, sinter forging, and hot pressing. Finite element results by using the proposed model also well predicted experimental data in the literature for densification behavior of nanocrystalline zirconia powder during pressureless sintering and sinter forging.

• Industry Promotion Research
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• v.9 no.1
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• pp.241-248
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• 2024

This study aims to determine whether happiness and hope mediate in the relationship between growth mindset and academic achievement among Chinese college students. Data were collected through a survey targeting 337 college students purposively sampled at a university in Guangdong, China. The collected data was analyzed using SPSS PC+ Win ver. 25.0 and SPSS PROCESS macro ver. 4.2. The statistical methods applied were frequency analysis, reliability analysis, correlation analysis, and dual mediation effect analysis. The conclusion of the study is as follows. First, growth mindset, happiness, hope, and academic achievement all showed significant positive correlations. Second, college students' happiness and hope double mediated the relationship between a growth mindset and academic achievement. Based on these results, this study proposed a plan to utilize not only a growth mindset but also happiness and hope to improve the academic achievement of college students.

• International Journal of Highway Engineering
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• v.15 no.3
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• pp.93-101
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• 2013

PURPOSES : This study is to investigate the relationship of socioeconomic characteristics and road network structure with traffic growth patterns. The findings is to be used to tweak traffic forecast provided by traditional four step process using relevant socioeconomic and road network data. METHODS: Comprehensive statistical analysis is used to identify key explanatory variables using historical observations on traffic forecast, actual traffic counts and surrounding environments. Based on statistical results, a multiple regression model is developed to predict the effects of socioeconomic and road network attributes on traffic growth patterns. The validation of the proposed model is also performed using a different set of historical data. RESULTS : The statistical analysis results indicate that several socioeconomic characteristics and road network structure cleary affect the tendency of over- and under-estimation of road traffics. Among them, land use is a key factor which is revealed by a factor that traffic forecast for urban road tends to be under-estimated while rural road traffic prediction is generally over-estimated. The model application suggests that tweaking the traffic forecast using the proposed model can reduce the discrepancies between the predicted and actual traffic counts from 30.4% to 21.9%. CONCLUSIONS : Prediction of road traffic growth patterns based on surrounding socioeconomic and road network attributes can help develop the optimal strategy of road construction plan by enhancing reliability of traffic forecast as well as tendency of traffic growth.

• Proceedings of the Technology Innovation Conference
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• 2001.06a
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• pp.145-156
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• 2001

This paper investigates the effect of imported technology on the economic growth of Korea. To this end, the relationship between input technology and economic growth are suggested in the numerical form and analysed empirically. The rates of return of technology investments, which are divided into the domestic R&D investment and the investment on imported technology, are estimated. Based on the result of this analysis, the rate of return of the input technology, which includes the domestic R&D investment and the investment on imported technology, are estimated as 31.4%, and this input technology is calculated as to contribute 8.9% on the economic growth rate of Korea. And the domestic R&D investment is fumed out to have bigger rate of return than the investment on imported technology during the surveyed period. However, the rates of return of detailed R&D investments, which can be divided into the investments on commercial R&D and basic science, were not calculated in this paper, because of the lack of data on this in this paper. As well, the time-lag effect, which is naturally believed to exist between the R&D investment and the economic growth, could not be analysed wit:1 the same reason. Thus when analysing the relationship between them, this paper tried to minimize the time-lag effect by using the long-term data of twenty-three years.

• The Research Journal of the Costume Culture
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• v.13 no.2 s.55
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• pp.255-268
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• 2005

The purpose of this study was to identify the physical characteristics of early adolescent girls by age. A total of 529 girls aged between 10 and 14 were measured and data were collected from 42 anthropometric and 41 photographic measurements per a person. SAS 8.1 was used in data analysis including means, standard deviations, t-test, Duncan test and frequency analysis. The results of this study are as follows. Most items related to height and length increased significantly at the age of $10\sim11$ and the growth slowed down at the age of $13\sim14$. As for items related to circumference, the growth rate was high at the age of $11\sim12$, and gradually slowed down afterward. Out of circumference items, hip circumference showed the highest growth rate. As for items related to thickness and width, thickness-related items grew quickly at the age of $10\sim12$, and among which bust thickness showed the highest growth rate. As for drop, the difference between hip circumference and waist circumference was most remarkable, but the difference between hip circumference and bust circumference was not large. The largest number of subjects had their menarche during the age of $11\sim12$ and, after menarche, their horizontal growth became active.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2000.11a
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• pp.346-356
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• 2000

This paper aims to analyse the relationship between R＆D investment and economic growth in Korea. The analysis result shows 38 percent of average economic growth rate(7.1%) of Korea between 1976 and 1998 was achieved by the growth of Total Factor Productivity (TFP), and the R&D investment during the period contributed in achieving the economic growth rate by as much as 9.86 percent. In the process of the estimate, the rate of return of the R&D investment from both government and private was calculated as 47 percent. The relationship between private R&D investment, government R&D investment and the GDP was also investigated, and it was estimated that the private sector invested 2.0 percent of the GDP in R&D during the period, and was found that 1 won of government R&D investment induced 0.202 won of private sector's R&D investment. However, the time-lag effect, which is naturally believed to exist between the R&D investment and the economic growth, could not be analysed in a mathematical form, because of the lack of the data to establish this relationship. However, this paper believe that the time-lag effect in this relationship was included implicitly by using the data of 23 years.

• Advances in nano research
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• v.3 no.3
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• pp.143-168
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• 2015

Initiation of crack and its growth simulation requires accurate model of traction - separation law. Accurate modeling of traction-separation law remains always a great challenge. Atomistic simulations based prediction has great potential in arriving at accurate traction-separation law. The present paper is aimed at establishing a method to address the above problem. A method for traction-separation law prediction via utilizing atomistic simulations data has been proposed. In this direction, firstly, a simpler approach of common neighbor analysis (CNA) for the prediction of crack growth has been proposed and results have been compared with previously used approach of threshold potential energy. Next, a scheme for prediction of crack speed has been demonstrated based on the stable crack growth criteria. Also, an algorithm has been proposed that utilizes a variable relaxation time period for the computation of crack growth, accurate stress behavior, and traction-separation atomistic law. An understanding has been established for the generation of smoother traction-separation law (including the effect of free surface) from a huge amount of raw atomistic data. A new curve fit has also been proposed for predicting traction-separation data generated from the molecular dynamics simulations. The proposed traction-separation law has also been compared with the polynomial and exponential model used earlier for the prediction of traction-separation law for the bulk materials.

• Journal of Korean Academy of Nursing
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• v.13 no.3
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• pp.51-60
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• 1983

Currently changing trends of child health care is demand total health assessment of child including growth and development. This study concentrates on the growth & developmental status of low birth weight infant for help their growth & development. Thus it can be provide a direction for scientific health education and counseling materials by investigating factor of growth & development. The subjects for this study were made up of 40 low birth weight infant who attended the well baby clinic of E university Hospital. The study method used was a questionnaire ＆ anthropometric assessment and DDST for normative data of development. The period for data collection was from July 1st to August 31th, 1982. Analysis of the data was done using percentages, $\chi$$^2$-test Stepwise Multiple Regression. The results of study were as follows. 1. The mean weight of birth was 2,068gm and mean of gestational period was 35.65 weeks. 2. The age at which weight ; 32.5%, head circumference : 67,5% chest circumference : 55.0%, height : 50. 0％ was normal range of physical growth. 3. The reverse age at which social development ; 87.5%, fine motor & adaptive development ; 70.0%, gross motor development ; 72.5% of children Passed by DDST to determine of normal range of development. 4. In the among variables, it was found that the infant who were the higher emotional & verbal response of mother and stimulus environment was the more normal range of weight & development than who was not. 5. The stepwise Multiple Regression between developmental status and predictors-birth order, weight at birth, sex, antenatal care, gestational period-are accounts for 34.1%.