• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.44-48
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• 1999

Uptake, assimilation and translocation of nitrogen and dry matter assimilation and translocation in ten rice cultivars were observed in no-till direct-sown rice-vetch cropping system. There was a large degree of variation in N-uptake, grain yield, nitrogen translocation efficiency and dry matter assimilation and translocation in tested rice cultivars. Forty kg N/ha base, as compound fertilizer (21-17-21% of N-P-K) three weeks after sowing and 30 kg N/ha top-dressed at panicle initiation stage as in the form of (NH$_4$)$_2$$CO_2$ was applied. ‘Newbounet’, ‘Daesanbyeo’, and ‘Hwayeongbyeo’ showed higher translocation efficiency. The contribution of pre-heading dry matter assimilates to grain ranged from 33% to 99% of dry grain weight. Dry matter of ‘Calrose 76’ was lower than Newbounet but N content was higher in Calrose 76 than Newbonnet. By maturity, N content in vegetative parts declined considerably more than dry matter, vegetative and reproductive parts, N translocation efficiency, and N harvest index. Nitrogen translocation efficiency was greater in ‘Nonganbyeo’, Daesanbyeo, and Newbounet. Grain N concentration was positively correlated with N concentration or N content of the vegetative parts at heading in Nonganbyeo, ‘Dasanbyeo’, ‘Dongjinbyeo’, and Newbonnet. These results indicated that the greater amount of dry matter and N accumulated before heading stage, the higher translocation rates of dry matter to grain and the greater net losses at maturity.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1623-1623
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• 2001

Composting is a biological method used to transform the organic waste into stable, humified organic amendments. Humification is indicated as the key factor in improving the quality of compost, because of the importance of humic substances to soil ecology, fertility and structure, and their beneficial effects on plant growth The compost constituents vary widely, however, the degree of maturity is very important factor in compost quality. So this experiment carried out to determine the rapid estimation of the quality in cattle, pig, chicken and waste composts using near infrared reflectance spectroscopy(NIRS). Near infrared reflectance spectra of composts was obtained by Infra Alyzer 500 scanning spectrophotometer at 2-nm intervals from 1100 to 2500nm. Multiple linear regression(MLR) or partial least square regression (PLSR) was used to evaluate a NIRS method for the rapid and nondestructive determination of humic acid contents in composts. The results summarized that NIR spectroscopy can be used as a routine testing method to determine quantitatively the humic acid content in the compost samples ondestructively. Especially, we supposed that absorbance around 2300nm is related to humic acid as a factor of compost maturity. However the NIR absorption approach is empirical, it actually requires many combinations of samples and data manipulations to obtain optimal prediction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.216-226
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• 1983

Genetic studies on the $F_2$ generation of a set of half diallel crosses involving six cowpea varieties were conducted. by the randomized block design with three replications to determine combining ability, gene action and the relationships between parents and their $F_2$ hybrids. The 12 agronomic characters namely, days to flowering, days from flowering to maturity, days to maturity, diameter of stem, length of internode, number of branches per plant, length of pod, number of pods per plant, number of grains per pod, number of grains per plant, 100 grain weight and grain weight per plot were observed, and the $F_2$ generation of this diallel set of crosses was analysed for each character according to the method by Jinks and Hayman. The results obtained are summarized as follows: 1. Vr-Wr graphical analyses; The following seven characters, days to flowering, number of branches per plant, length of pod, number of pods per plant, number of grains per plant, 100 grain weight and grain weight per plot appeared to be partially dominant, and over dominance was found for days from flowering to maturity, days to maturity, length of internode and number of grains per pod. But diameter of stem indicated partial dominance near complete dominance. 2. Estimates of genetic variance components; In the degree of dominance,. eight characters, that is, days to flowering, days from flowering to maturity, days to maturity, length of internode, number of pods per plant, number of grains per pod, number of grains per plant and grain weight per plot were expressed larger than 1. And the characters, days from flowering to maturity, number of branches per plant and number of grains per plant as the degree of mean dominance ($H_1$/D) were found to be negative value over other characters. On the other hand, apprent asymmetry of dominance-recessive allele ($H_2$ /$4H_1$) produced comparatively estimates with lower value on days from flowering to maturity, length of internode, number of branches per plant and number of grains per pod. 3. Analyses of combining ability; Mean square value of GCA(general combining ability) appeared to be more important than those of SCA (specific combining ability) for most characters, and among them, grain weight per plot showed the highest mean square value in GCA and SCA. 4. Effect of combining ability; Variety 178 was expressed as the highest GCA effects in five characters (days to flowering days to maturity, number of pods per plant, number of grains per plant and grain weight per plot). SCA effects were differed from parents, characters and crosses, but crosses between TVu 1857 $\times$ TVu 2885 and TVu 2702 $\times$ J78 were shown to be highly with SCA effects on yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.173-183
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• 1983

To evaluate growing degree days(GDD) as an index of growth duration of rice plants, 30 days old seedlings of 16 japonica and 14 indica/japonica varieties were transplanted six times from May 10 at the 10-day intervals at Gyeongsan in 1982. The number of days from transplanting to heading decreased as transplanting dates delayed in all japonica varietie and 4 indica/japonica varieties but that of 10 indica/japonica varieties decreased up to June 9 or June 19 transplantings and then it levelled off or increased with further delay of transplanting. However, GDD requirement was similar among transplanting dates at appropriate base temperatures; GDD could be better than calendar day system to classify maturity of varieties especially grown in a wide range of climatic conditions. Required GDD from transplanting to heading of all indica/japonica and early japonica varieties showened a smaller coefficient of variation (CV) compared to longer season japonica varieties. Among GDD methods, an accumulation of daily Max + Min temp./2 -$l0^{\circ}C$ showed the smallest CV for the duration from transplanting to heading, but for ripening period GDD calculated with adjusted maximum temperature when it was higher than $30^{\circ}C$ showed the best results. Heading date did not affect required GDD for maturity of japonica varieties, but in indica/japonica varieties GDD decreased as heading date delayed; at late transplantings ripening period of indica/japonica varieties was less extended compared to japonica varietes due to a decrease in grain weight.

• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.123-130
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• 2006

Principal aim of this study is to suggest the statistical equation model which can predict an amount of ammonia emission according to the degree of compost maturity during composting livestock manure. Composting process was classified with intial, midterm and final phase based on germination index of compost samples. Total Kjeldahl nitrogen(TKN) and organic matter(OM) were selected as the independent variables available to contribute to ammonia emission from composting pile. Ammonia concentration measured in the samples taken at the intial phase was about 10ppm, sharply increased to 50ppm at the midterm phase, and gradually decreased to about 10ppm. The contents of Total Kjeldahl nitrogen and organic matter through whole composting period were ranged from 0.6 to 1.2% and from 30 to 40%, respectively, were reduced slightly at the midterm phase, but generally showed no constant fluctuation pattern. In estimating ammonia emission with application of the statistical equation model, the coefficients of independent variables at the midterm phase when an average concentration of ammonia was highest showed a relatively high values whereas those at the initial phase when an that of ammonia was lowest indicated a relatively low values. However, no statistical significance was found in the coefficients of independent variables and the equation model. Additionally, the further research, which can include the considerable analysis data with more samples taken than this study, is needed in order to suggest the statistically significant equation model available to predict ammonia emission during composting process.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.359-365
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• 1994

A oat (Avena sativa) cultivar, 'Guiri 16', was seeded on Oct. 9, Oct. 24, Nov. 9, Nov. 24, Dec. 9 of 1991 and 1992 to determine usefulness of growing degree days (GDD) for predicting growth duration and the optimum seeding date of oats for grains in Cheju province. The later the seeding, the greater the number of days to emergence but the fewer the number of days to heading and maturity. As seeding was delayed, accumulated GDD from seeding to emergence generally tended to decrease but was less subjective to a constant downward tend over seeding date than the number of days. Accumulated GDD from emergence ot heading decreased with delaying seeding and accumulated GDD from heading to maturity decreased as seeding was delayed up to Nov. 24. As seeding was delayed from Oct. 9 to Dec. 9, to Dec. 9, leaf area index at heading decreased from 7.7 to 5.1 and dry matter yield at maturity from 1920 to 823 kg /10a in 1992-1993, and culm length 120 to 89cm on an average of 1991-1992 and 1992-1993. While the number of grains per panicle and test weight were not affected by seeding date in 1991-1992 and 1992-1993, the number of panicles per m$^2$ and grain yield were decreased when oats were seeded earlier or later than Nov. 9. 1000 grain weight was not affected by seeding date in 1991-1992 but greatest at Nov. 9 seeding in 1992-1993. The results indicate that optimum seeding date of oats in Cheju province would be early November. November.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.269-277
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• 2019

It is important to determine sowing date as it decisively affects the quality as well as quantity of waxy corn. In the central northern area of Korea, optimum sowing date of waxy corn is May and requires about 20-26 reproductive growth days from silking date to harvest. We determined adaptable sowing date of waxy corn varieties using growing degree days (GDDs), especially in the central northern area. Earlier sowing required many more emergence days owing to the low temperature. All waxy corn varieties required about 16~22 emergence days when sown in April. Otherwise, less than 15 emergence days were needed for sowing from May to August. Sowing dates to maximize ear yield of waxy corns were different depending on the eco-types of corn varieties as well as GDDs during the growth period. Early maturity type Mibaek2' showed the highest ear yield at the May $15^{th}$ sowing date. Middle maturity 'Iimichal' and late maturity 'Chalok4' showed the highest ear yield at the May $25^{th}$ and June $5^{th}$ sowing dates, respectively. GDDs of 26 days after silking was an index to determine the highest yield sowing date of 'Mibaek2'. The total GDDs from sowing to harvest and to silking were other indexes to determine the highest yield sowing date of 'Ilmichal' and 'Chalok4', respectively. Generally, it required about $2,400^{\circ}C$ GDDs from sowing date to maturity and at least 65 days of silking date from sowing to obtain about 1,200kg of ear yield of waxy corn in the central northern area of the Korean peninsula. The results of the study will be helpful for corn farmhouses to determine optimum sowing date of waxy corn in the central northern area of Korea.

• Journal of Convergence for Information Technology
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• v.8 no.2
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• pp.19-27
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• 2018

The purpose of this study is to examine career maturity, self - management, and university life satisfaction according to general characteristics of college students. 403 students from Daegu and Gyeongbuk provinces were analyzed and analyzed by hierarchical multiple regression analysis focusing on factors such as general characteristics, personality traits, career attitude and self - management. As a result, according to the frequency and general characteristics of university life satisfaction, overall university life satisfaction was 3.29 out of 5 out of 5, and fresh students were higher than second year students. Also, the more open the personality, the higher the sincerity. The more self - management is the student who manage the life, the better the proper behavior management and physical management. In addition, students with a lower level of personality and a higher degree of readiness were more satisfied with college life than attitudes toward career maturity than those with lower grades. Based on these results, students with friendly characteristics can prepare well in career attitude maturity It is important to guide students well so that they can improve their college life satisfaction.

• Food Science and Preservation
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• v.20 no.3
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• pp.304-316
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• 2013

To determine the appropriate harvest maturity of mulberry to prolong the freshness during distribution, mulberries were classified into three groups (80%, 90%, and 100%) based on their degree of maturity and then compared for their firmness, color, anthocyanin, soluble solids content, pH, titratable acidity, viable cell, mold and sensory quality. They were then investigated for quality changes by maturity under different distribution temperature at $20^{\circ}C$, $10^{\circ}C$ and $0^{\circ}C$. Immediately after harvest, the 80% matured mulberries were shown to be the firmest and 1.74 and 2.64 times firmer than 90% and 100% matured mulberries respectively. The more mature the mulberries were the lower the "a" value was while anthocyanin content was higher. The soluble solids content and pH of mulberries increased as they matured. Less mature the mulberries were the higher titratable acidity was and lower microbial levels in mulberries were. In terms of sensory quality, color of the 100% matured mulberries was the highest but the 90% matured mulberries were most preferred based on other sensory indexes. In comparison to storability of mulberries by maturity, although the firmness of the 80% matured mulberry decreased rapidly, they were the firmest during distribution periods. The level of mold of the 100% matured mulberries was higher than others. Moreover, the more mature mulberries were the quicker they deteriorated. According to quality indexes, depending on maturity and sensory evaluation of mulberry distributed at different temperatures, the storability of the 80 and 90% matured mulberries were higher than that of the 100% matured mulberries. In conclusion, judging by their sensory quality, the 90% matured mulberries were more appropriate for harvesting than the 80% matured mulberries.

• Computers and Concrete
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• v.11 no.4
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• pp.271-289
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• 2013

In this research, a developed microstructural model of cement particles was presented to describe the cement hydration procedure. To simplify the hydration process, the whole hydration was analyzed in a series of sub-steps. In each step, the hydration degree, as well as the microstructural size of the hydration cell, was calculated as a function of the radius of the unreacted cement particles. With the consideration of the water consumption and the reduction of the interfacial area between water and hydration products, the micro-level expressions of the cement hydration kinetics were established. Then the heat released and temperature history of the concrete was carried out with the hydration degree obtained from each sub-steps. The equivalent age method based on the Arrhenius law was introduced in this research. Based on the equivalent age method, a maturity model was applied to describe the evolution of the mechanical properties of the material during the hydration process. The finite element program ANSYS was used to analyze the temperature field in concrete structures. Then thermal stress field was calculated using the elasticity modulus obtained from code formulate. And the risk of thermal cracking was estimated by the comparison of thermal stress and concrete tensile strength.