• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.4
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• pp.343-349
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• 1993

This study was conducted 1)to determine the factors responsible for the gradually increased rice yield by examining any improvements in yield-related characters and physiological characters among the historically recommended varieties of rice in Korea, and 2)to reveal the way of achieving further yield improvement by breeding in the future. Eight recommended varieties from 1911 to 1988 were selected and grown at the same conditions. The yield-related characters were observed at the harvest time, and the physiological characters such as RGR, NAR, LAR, SLA and L WR were estimated by the classical method of growth analysis. The newer varieties are shorter and those released after 1970's are greater in percent of filled spikelets and harvest index than the older varieties. There are no definite changing trends in the variations of number of panicles per hill, number of spikelets per panicle and 1000 grain weight according to the course of evolution in the recommended varieties. There is little evidence of improvement in the physiological characters such as NAR, LAR, SLA and LWR among the recently developed varieties compared with those of the older varieties. The increase in grain yield due to variety improvement, if any, is largely associated with the greater harvest index and percent of filled spikelets by breeding blight resistant and / or lodging resistant genotypes with short culm. It is suggested that increase in NAR should be carried out simultaneously with increase in harvest index to breed high yielding genotypes. I t appears to be important to breed genotypes with long culm in order to enhance light penetration into the canopy as long as they are lodging resistant. Since NAR is negatively correlated with LAR, it is unlikely to succeed to improve both characters simultaneously. The direct effect of NAR on RGR by path analysis is much larger than that of LAR, and hence it is suggested that breeding genotype with large NAR is more effective on enhancing RGR. It is also suggested that improving LAR through LWR is likely effective on increasing RGR.

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.220.3-221
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• 2002

• Journal of Korean Home Economics Education Association
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• v.17 no.3 s.37
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• pp.83-96
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• 2005

To assess the food intake and diet quality of high school students who live in Chuncheon area, a dietary survey using 24-hour recall method was conducted with 318 subjects. $71.4\%$ of total food intake was in the form of plant foods and the rest on the form of animal food. Diet quality was assessed by food group pattern, dietary diversity score(DDS), and dietary variety score(DVS). When counting the major food groups consumed, $37.1\%$ of subjects had a DDS of 3 and $48.4\%$ of subjects had a DDS of 4. When investigating the consumption pattern of the major five food groups, only $14.5\%$ of subjects consumed foods from all five groups. On average, subjects habitually consumed 26.7 different foods daily, with the mean score of diet variety for males (27.3) being significantly higher than for females (25.8) . Correlation coefficients between nutrient adequacy ratio (NAR) and DVS ranged from r=0.39 for vitamin $B_2$ to r=0.61 for phosphorus. NAR also improved as the number or foods or rna groups consumed increased (p<0.001). Associations between the NAR and high level of DVS was more positive than those between the NAR with DDS. When assessing the dietary quality of subjects using DDS and DVS, many people appeared not to have a desirable food intake. Therefore, to lead them to have nutritionally balanced diet, educating students and their parents on nutrients and suggesting guidelines for a desirable diet is considered to be essential so that they can intake from all of major food group and have various foods in their diet.

• Korean Journal of Community Nutrition
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• v.4 no.1
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• pp.74-82
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• 1999

This study evaluated the quality of meals served by the elementary schools in Muan based on nutrient contents and food diversity. The contents, nutrient densities and nutrient adequacy ratios(NAR) of most nutrients were higher than those calculated from the Korean RDA. However, the content, nutrient density, and NAR of iron were lower than those calculated from the RDA for 10 to 12 year old girls. The content of sodium was somewhat high. The average number of different kinds of food and dishes per meal were 19.2 and 6.0, respectively. The more the number of dishes, the higher the NARs of calcium, calories, niacin, phosphorus and protein. However, the NAR of iron showed no correlation with the number of dishes. The meals belonging to the food group intake pattern containing fruits had more vitamin C and fiber, and less protein, lipid, and phosphorus than those belonging to the food group intake pattern not containing fruits. In conclusion, the quality of nutrition of meals served by school lunch program(SLP) was considered fairly good. However, the nutritionists should consider the iron for 10 to 12 year old girls and cut down the amount of sodium. In addition, unless the children prefer the foods served by SLP or adjust to the general aspects of SLP, SLP can't accomplish its purposes. Therefore, we suggest that nutritionists should survey children's food preference and satisfaction with the general aspects of SLP.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1553-1558
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• 2002

This study was carried out to obtain informations regarding the effect of N-acetyl-D-glucosamine in the LEY (lactoseegg yolk) diluent according to incubation time in 5 ml maxi-straw and the effects of freezing rate, thawing temperature and thawing time in the LEN (lactose-egg yolk and N-acetyl-D-glucosamine) diluent on acrosome morphology and motility of frozen-thawed boar sperm. The study showed that the LEN diluent was higher post-thaw NAR (normal apical ridge) acrosome than the LEY diluent for 0.5 h incubation at 37$^{\circ}C$. However, there were no differences between the LEN and LEY diluents on post-thaw sperm motility according to incubation time. The straws frozen from 5.0 cm (20$^{\circ}C$/min) to 17.0 cm (1$^{\circ}C$/min) above the liquid nitrogen surface did not show any significant differences on post-thaw sperm motility. However, the straws frozen above 5.0 cm from the liquid nitrogen surface were higher NAR acrosome than those frozen above 17.0 cm. The post-thaw percentages of motile sperm and NAR acrosome were significantly higher (p<0.05) for the maxi-straws submerged for 40 or 45 sec in a 52$^{\circ}C$ water bath than for 30, 35, 50 or 55 sec. The mean sample temperatures of maxi-straws after 40 or 45 sec submersion were 20.7 or 26.4$^{\circ}C$. In conclusion, the sample temperature of the thawed semen was very important for post-thaw sperm survival in the LEN diluent of 5 ml maxi-straw. When the temperature of the thawed semen was 20.7$^{\circ}C$, the percentages of motile sperm and NAR acrosome were highest.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.723-738
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• 2014

This study examined nutrient intake of long-lived men and women living in Jeollanam-do (Gangjin, Goksung, Gurye, Damyang, Boseong, Suncheon, Jangheung) which is known as representative Korean longevity area. Using the 24 hr recall method, dietary nutrient intake data were collected from 134 subjects (67 for 80~89 years old, 67 for more than 90 years old) in spring and fall 2012. Nutrient for each subject were calculated using CAN-pro. Subjects' daily mean intake levels of macronutrients, vitamins and minerals were higher in fall than in spring. Compared to KDRIs, subjects less than recommend (RNI/AI). East consumed nutrients compared to KDRIs were folate, potassium, calcium, vitamin $B_1$, vitamin $B_2$ and vitamin E. Subjects 232.8~363.1% of recommended intake level for natrium. The nutrient adequacy ratio (NAR) was 0.87 for subjects in their 80s and 0.79 for than 90 years old. The average NAR of all subjects was 0.83. The index of nutritional quality (INQ) exceeded 1 for most nutrients except for Ca (0.87), K (0.77), vitamin $B_1$ (0.84), vitamin $B_2$ (0.70) and folate (0.68). The average INQ was 1.31. This study concluded that even though long-lived men and women living in Jeollanam-do consumed less than RNIs, nutrition consumption quality was relatively fine based on NAR and INQ results.

• Journal of the Korean Dietetic Association
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• v.11 no.1
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• pp.114-124
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• 2005

The nutritional status of pre-school children is important for both physical growth and functional development. This study investigated the anthropometric, nutrient intakes and dietary quality of the pre-school children living in Asan for planning nutritional education program. The dietary intakes were measured by 2-day 24 hr recall recorded by children's mothers and the anthropometric data were collected by measuring children's weights, heights, and percent body fat at Asan Public Health Center. The children were 161 boys and 129 girls aged 5 and 6 years. When children's nutritional status was determined by their anthropometric status (underweight, normal weight and overweight) determined by z-score (normal range between -1.00 and 1.00), only 1.4% of the children belonged to underweight group while 55.7% and 42.9% belonged to normal and overweight groups, respectively. Significantly higher number of children belonged to overweight group for 5 year-olds. No differences were observed in nutrient intakes, nutrient adequacy ratio (NAR) and index of nutritional quality (INQ) values among nutritional status groups. Intakes of the most nutrients were adequate, but NAR and INQ of calcium and zinc were low. When nutrient intakes, NAR and INQ were compared by sex or age, all nutrient intakes were appropriate except calcium and zinc intakes of 6 year-olds. Nutrient intakes of 5 years were higher than those of 6 years. The mean of nutrient adequacy ratio (MAR) was 0.85 and mean INQ was 1.51 for all participants. The nutritional management program for pre-school children in Asan would be directed differently by age groups and education material should contain contents educating to consume moderate amount of food for 5 year-olds and to increase intake of foods with mineral nutrients such as calcium and zinc for 6 year-olds.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.2
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• pp.103-114
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• 2007

The existing handover authentication schemes have authentication delay and overhead of the authentication server since they have been separately studied handover authentication at the link layer and the network layer. This paper proposes a handover authentication scheme initiated by Mobile Node on FMIPv6 based mobile access networks. The main idea of the paper is to generate a session key at the mobile node side, and transfer it to the next Access Router through the authentication server. Also, the scheme has a hierarchical key management at access router. There are two advantages of the scheme. First, the generated session key can be utilized for protecting the binding update messages and also for access authentication. Second, hierarchical key management at the access router reduced the handover delay time. The security aspects on the against PFS, PBS, and DoS attack of proposed scheme are discussed.

• Asian Journal of Turfgrass Science
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• v.15 no.2
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• pp.65-76
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• 2001

This study was designed to estimate on the interaction of the first productivity, light condition and to examine the ecophysiological characteristics of Zoysia japonica. rtificial community of Zoysia japonica was analyzed effect of matter production and growth construction under various shading condition. The results summarized this experiment were as follows; 1. The relative growth rate (RGR) in all experimental plots was high during the growth stage of 20 days after transplanting, and then decreased. The maxium RGR value appeared in the control plot (2.13g/g. 10days) during the growth stage from 10 to 20 days after transplating. RGR value in server shading of short day condition was remarkably decreased from the early growth stage. The main factor to lower RGR value considered as a short day condition than that of shading. 2. The net assimilation rate (NAR) in all experimental plots except 3hour photoperiod plot was high during the early growth stage after transplanting, and then decreased early growth stage after transplanting, and then decreased as the growth proceeded. The maxium value appeared in the control plot (35g/g. 10days). NAR value in the severe shading of short day condition plots was low. Especially, NAR value in the three hours photoperiod plot was remarkably low from the early growth, there was no great difference by growth stage. NAR had negative correlation with LAI and positive correlation with RGR. 3. The increasing rate of leaf area ratio(LAR) was high during the early growth stage after transplanting in the control plot and in the photoperiod plot, the shorter the exposure time to sunlight, the higher the LAR value from the early growth stage. Especially, its value in the 3 hour photoperiod plot was remarkably high but its increasing rate was lower as the growth proceeded. LAR hade negative correlation on RGR and NAR. 4. The crop growth rate(CGR) in each experimental plot was increased until 50 days after transplanting, and then decreased. After that time, the maxium CGR value appeared in the control plot (1.56g/$\textrm{cm}^2$. 10-days), 60 days after transplanting, CGR had positive correlation with LAI. The optimum LAI in the control, 9 hour, 7 hour, 5 hour, and 3 hour photoperiod plots appeared as 1.87, 1.12, 0.83, and 0.18.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2371-2374
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• 2014

A kinetic study is reported on SNAr reaction of 1-fluoro-2,4-dinitrobenzene with a series of primary amines including hydrazine in $H_2O$ at $25.0^{\circ}C$. The plots of $k_{obsd}$ vs. [amine] are linear and pass through the origin, indicating that general-base catalysis by a second amine molecule is absent. The Br${\o}$nsted-type plot exhibits an excellent linear correlation with ${\beta}_{nuc}$ = 0.46 when hydrazine is excluded from the correlation. The reaction has been suggested to proceed through a stepwise mechanism, in which expulsion of the leaving group occurs after the rate-determining step (RDS). Hydrazine is ca. 10 times more reactive than similarly basic glycylglycine (i.e., the ${\alpha}$-effect). A five-membered cyclic intermediate has been suggested for the reaction with hydrazine, in which intramolecular H-bonding interactions would facilitate expulsion of the leaving group. However, the enhanced leaving-group ability is not responsible for the ${\alpha}$-effect shown by hydrazine because expulsion of the leaving group occurs after RDS. Destabilization of the ground-state of hydrazine through the electronic repulsion between the nonbonding electron pairs is responsible for the ${\alpha}$-effect found in the current $S_NAr$ reaction.