• Journal of the Korean Home Economics Association
• /
• v.47 no.1
• /
• pp.65-73
• /
• 2009

The present longitudinal study examined reciprocal influence between self-esteem and academic achievement using cross-lagged autoregressive model. This study employed data(four wave) from Korea Youth Panel Survey. Participants were 300 students(143 boys, 157 girls) who were 4th graders in 2004 and 7th graders in 2007. The results of this study indicated that 4th graders' self-esteem influenced 5th graders' academic achievement, in turn, 5th graders' academic achievement influenced 6th graders' self-esteem. However, students' self-esteem in 6th grade did not influence their academic achievement during 7th grade. Conversely, 6th graders' academic achievement influenced 7th graders' self-esteem.

• The Korean Journal of Community Living Science
• /
• v.14 no.1
• /
• pp.97-105
• /
• 2003

This study was to examine the contents of sexuality education in the 6th Home Economics 1 and in the 7th Technology.Home Economics 1 of Middle school curriculum by comparing those two text books. The result of the study was that: 1) the 7th TechnologyㆍHome Economics 1 has more sexuality education contents than in the 6th; 2) the 7th TechnologyㆍHome Economics 1 used much more vivid and realistic pictures to catch students' attention and bring educational effect; 3) the 7th Technology \ulcornerHome Economics 1 included more detailed information for the young students such as pregnancy, birth control, masturbation, artificial abortion, and prevention of sexual violence than the 6th; 4) although the 7th TechnologyㆍHome Economics 1 showed more developed contents for the sexuality education, it had still only theory based information that lost students' attention on this important issue.

• Journal of Navigation and Port Research
• /
• v.31 no.2
• /
• pp.159-163
• /
• 2007

In this paper, we mainly analyze the performance of two ultra wideband communication systems, the classical Time Hopping Binary Pulse Position Modulation (TH-BPPM) UWB system and the Time Hopping Bipolar Pulse Amplitude Modulation (TH-BPAM) UWB system. The performance of TH-BPPM and TH-BPAM is analyzed in detail under an ideal AWGN channel and a correlation receiver. We use the power spectral density function to get the expression of BER of these two UWB systems. It yields simple and exact formulas relating the performance to the system parameters. The analysis shows that TH-BPPM suffers performance degradation with respect to TH-BPAM. Furthermore, we give the computer simulation of both data and image transmission and our simulation results also prove our theoretical analysis.

• Journal of the Ergonomics Society of Korea
• /
• v.31 no.1
• /
• pp.219-235
• /
• 2012

Objective: The aim of this study is to analyze the change characteristics of boys among the ages of 13 and 18 years. This study is based on the $4^{th}$ to the $6^{th}$ national anthropometric survey(Size Korea) data. Background: Many changes can affect the body characteristics compared withthe past. The significant changes were shown in Pepsi generation according to the report of national anthropometric survey of Korea 1997. Method: The subjects of the survey were 1,899 boys of the $4^{th}$ Size Korea, 1,587 boys of the $5^{th}$Size Korea and 2,317 boys of the $6^{th}$ Size Korea, who were from 13 to 18 years old. The change characteristics were analyzed withanthropometric measurements, height index value and proportion. Results: Stature was increased in 17~18 years old age group of the $5^{th}$ and the $6^{th}$ Size Korea and height items of the lower body showed the tendency to increase as the $6^{th}$ Size Korea over the time. In the case of circumference items, the tendency to increase in the $5^{th}$ and the $6^{th}$ Size Korea was observed. If the $5^{th}$ and the $6^{th}$ Size Korea were compared, there were no changes of other circumference items but chest circumference of the $6^{th}$ Size Korea was decreased in comparison with the $5^{th}$ Size Korea. Waist breadth(natural indentation) was increased in the $6^{th}$ Size Korea in spite of chest breadth was decreased in the $5^{th}$ and the $6^{th}$ Size Korea. And shoulder length, biacromion length and bishoulder length were decreased. The proportion of chest circumference, abdominal extension circumference and hip circumference to waist circumference and the proportion of chest breadth to waist breadth(natural indentation) showed the tendency to decrease as the $6^{th}$ Size Korea over the time. Conclusion: There was no change of stature excluding 17~18 years old. Circumference items showed tendency to increase as the $6^{th}$ Size Korea over the time. Shoulder and chest breadth became narrow. The somatotype changed to board chest with narrow waist in comparison with the previous. Application: In this way, the body size of 13~18 years' old boys changes. If these change characteristics reflects to the school uniform design, research for the pattern development, and etc., these will be able to improve fit and satisfaction of clothes.

• The Journal of Industrial Distribution & Business
• /
• v.9 no.3
• /
• pp.31-43
• /
• 2018

Purpose - With the technology of the 4th industrial revolution, business models of agricultural sector are changing rapidly toward convergence and high value-added business models due to the 6th industrialization of agricultural. Our goals is to examine the 6th industrialization of agriculture, and then to apply the technology of the 4th industrial revolution to the 6th industrialization of agriculture, suggesting the possibility of future agriculture, and then linking the export competitiveness of agricultural products. Research design, data, and methodology - As the methodology, case studies and empirical analyzes were conducted as well as literature studies. The case analyses included tomatoes, pig breeding farms, and an empirical analysis was conducted using the AHP analysis by experts of the 6th industrialization. In addition, using 124 survey data, this study examined and analyzed the items of the 4th industrial revolution technology for the 6th industrialization of agriculture and the strengthening of export competitiveness. Results - Results showed that the technology of the 4th Industrial Revolution helped "6th industrialization of agriculture" and "the strengthening of export competitiveness" using two successful cases. The AHP analysis was also carried out, and it was found that the improvement of the technology in the 4th industrial revolution could contribute to the future industrialization as well as the 6th industrialization of agriculture. First of all, we looked many conditions were important and urgent. Among the technologies of the 4th industrial revolution, the mobile, big data were important. Moreover, it was recognized that linkage and convergence related efforts would greatly contribute to strengthening export competitiveness of agriculture such as price and quality competitiveness. Conclusions - The 4th industrial revolution such as hyper-connectivity, hyper-intelligence and hyper-predictability contribute greatly to the 6th industrialization of agriculture, and therefore it is essential to improve the competitiveness of the agricultural sector by using the technology of the 4th industrial revolution. In particular, based on analyses of the diamond model, the "demand conditions" was the most important factor for the activation of the 6th Industrialization, and then "related and supporting fields", "factor conditions" and "business context" were followed in order. The results of this study can be useful for policy, practical and academic sectors.

• Journal of Nutrition and Health
• /
• v.22 no.1
• /
• pp.36-41
• /
• 1989

In this study longitudinal of the taurine content in the human milk of 23 Korean lacto-ovo-vegetarian women was studied during the lactating periods of the 15th, 30th, 60th, 90th, 120th and 150th day after delivery. The results of the study on primiparae and multiparae studied separately are as follows: 1) The taurine content of the primiparae per 1ml of human milk was 356.1nmole on the 15th day, 238.6 nmole on the 30th day, 249.6 nmole on the 60th day, 148.7 nmole on the 20th day, and 139.6 nmole on the 150th day. There was a significant decrease in the measns. 2) The taurine content of the multiparae per 1ml f human milk was 401.6 nmole on the 90th day, 189.9 nmole on the 120th day, and 159.8 nmole on the 150th day. There was a significant decrease in the measns. 2) The taurine content of the multiparae per 1ml of human milk was 401.6 nmole on the 15th day, 342.3 nmole on the 30th day, 273.2 nmole on the 60th day, 248.6 nmole on the 90th day, 189.9 nmole on the 120th day, and 159.8 nmole on the 150th day. There was a significant decrease in the measns. The multipareas had higher taurine content in every lactating period than the primiparae but there was not a significant difference. The correlation between the changes durinig lactating periods and the taurine content was negative. The correlation coefficient of the primiparae was -0.641 and that of the multiparae was -0.753. The overall correlation coefficient of the primiparae and the multiparae is -0.644, decreasing significantly up to the 150th day.

• The Mathematical Education
• /
• v.50 no.3
• /
• pp.367-381
• /
• 2011

It is important to concern about individual difference on every subject and every class. How can we know the individual difference? It is helpful for that to find out students' math learning style and learning type. In this paper, I conducted a survey to look for math learning style and math learning type of 4th, 5th and 6th grade students, and analyzed those data. The research findings are summarized as follows; First, 4th, 5th and 6th grade students prefer the visual learning style to the verbal style, and they have more wholistic tendency than analytical tendency in the domain of the cognitive learning style. Second, they prefer the authoritative and goal-oriented learning style to the practical and recreational learning style, and they have more interior-oriented than exterior-oriented in the domain of affective learning style. Third, the representative math learning type of 4th, 5th and 6th grade students is visual/holistic/authoritative and goal-oriented/interior-oriented. The math learning styles of students have a lot of influence on their learning, so that an appropriate teaching method for each student could arouse a maximum effect in the math study.

• Korean Journal of Veterinary Research
• /
• v.11 no.2
• /
• pp.117-122
• /
• 1971

This experiment was performed to study the effects of radioactive phosphorus($^{32}p$) on the growth of chick embryo and young chick. Radioactive phosphorus($^{32}p$) was administered into the yolk sac of chick embryo in doses of 2 uci/gm and 1 uci/gm and was administered intraperitoneally to the young chick in doses of 1 uci/gm and 0.5 uci/gm. The chick embryos were sacrificed on 6th, 7th, 8th, 9th and 10th day and the chicks were sacrificed on 1st, 3rd, 6th and 10th day after the administration and the liver, kidney, spleen, brain, eye ball and femur were weighed to observe the effects of growth inhibition on them. The results obtained were as follows. 1. A marked growth inhibitory effect was found on 8th, 9th and 10th day after the administration of $^{32}p$ in chick embryos and the same effect was found on 6 th and 10 th day after the administration in chicks. 2. The growth of the liver, kidney, spleen and femur was inhibited markedly but the brain and eye ball were not affected in chick embryos and chicks.

• Korean journal of food and cookery science
• /
• v.17 no.2
• /
• pp.149-155
• /
• 2001

Namul cooked with the standard recipe was examined by research of microbiological test for three months and sensory evaluation of frozen namul after reheating. When the namul was freezed storage, in the microbiological test namul began to change on the 40th day, but there was no problem about stability of storage until 3 months. The overall qualities of taste, flavor, color and texture were examined by sensory evaluation of frozen namul after reheating. The pH was seemed to change slowly, its color was changed on the 20th day from the beginning of storage. Radish root represented substantial difference in texture and overall quality on the 20th day. The off-flavor of immature pumpkin stated on the 25th day. Later 10days nettle tree mushroom began to be changed in its taste, texture, overall quality and appearance, then on the 25th day it was seemed to have low preference. But oak mushroom kept its quality good for 25 days. Oyster mushroom was changed in color, appearance and overall quality on the 20th day. Bracken had low preference in taste, texture and moisture on the 25th day. The color of spinach was changed on the 15th day, and its taste on the 20th day. Soybean sprout was changed in taste, texture and overall quality on the 15th day, and overall quality marked low preference on the 25th day Root of bell flower was changed on the 25th day(p<0.05).

• Journal of Environmental Science International
• /
• v.25 no.2
• /
• pp.289-294
• /
• 2016

In this study, we examined the impact of transplant timing of mother plants for seedling strawberry on growth and development of daughter plants and field stage. The leaf growth of treated mother plants and crown thickness were low when transplant was performed on April $10^{th}$. Based on the results collected until July $13^{th}$, the numbers of daughter plants with more than two leaves were 20.6 and 19.5 for March $10^{th}$ and March $25^{th}$, and these values decreased by April $10^{th}$ and April $25^{th}$ showing values of 15.1 and 11.8, respectively. After seedling growth was complete, leaf area and fresh weight of the saplings were remarkably low beginning from the transplant on April $10^{th}$. Crown thickness of saplings was generally lower when transplant timing was late. After 45 days of transplant leaf length and width were noticeably lower than the transplant on April $10^{th}$ and $25^{th}$. First cluster was 100% for both the March $10^{th}$ and $25^{th}$ transplant, followed April 10th and $25^{th}$ with values of 66% and 43%. The results revealed that transplant on March $10^{th}$ and $25^{th}$ had a greater positive impact on the growth and development of the strawberry cultivar 'Seolhyang'. A supplementary study will have to be conducted to determine the relationship between the harvest period of the first cluster and the yield of marketable strawberries depending on the transplanting time of mother plants.