• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.259-262
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• 2009

The influence of pre-strain in low-cycle fatigue behavior of Fe-18Mn-0.05Al-0.6C TWIP steel was studied by conducting axial strain-controlled tests. As-received plates were deformed by rolling with reduction ratios of 10 and 30%, respectively. A triangular waveform with a constant frequency of 1 Hz was employed for low cycle fatigue test at the strain amplitudes in the range of ${\pm}0.4{\sim}{\pm}0.6$ pct. The results showed that low-cycle fatigue life was strongly dependent on the amount of pre-strain as well as the strain amplitude. Increasing the amount of prestrain, the number of reversals to failure was significantly decreased at high strain amplitudes, but the effect was negilgible at low strain amplitudes. A new model for predicting fatigue life of pre-strained body has been devised adding a correction term of ${\Delta}E_{pre-strain}$ to the energy-based fatigue damage parameter.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제19권2호
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• pp.89-100
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• 2015

The study investigated pre-service teachers' knowledge and computational skills by using Triangular Arithmagon. Participants included 90 pre-service teachers from two schools in the United States and Taiwan. The Triangular Arithmagons Test (TAT) was used to measure pre-service teachers' performance in whole number, fractions, and decimals operations (i.e., addition, subtraction, multiplication, and division), each of which included level-1 (basic) and level-2 (advanced) tests. MANOVA analysis was performed to compare the performance between teachers from the United States and Taiwan. Results indicated that overall, pre-service teachers in Taiwan outperformed those in the United States, especially on the advanced-level tests. Pre-service teachers in the United States were found to have poor ability of solving complex operation problems. Different curriculum plans and teaching methods may lead to the performance gap between the two countries.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.541-544
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• 1992

Duck eggs from Indigenous (desi), Khaki Campbell and Crossbred (Indian Runner $\times$ Khaki Campbell, $F_1$) were incubated to investigate fertility, hatchability and other related traits. The fertility was highest in crossbred followed by Khaki Campbell and Indigenous ducks respectively. The embryonic mortality was highest in Khaki Campbell followed by Indigenous and crossbred respectively. The embryonic mortality was higher in eggs of 7 days pre-incubation holding period and lower in eggs of 3 days pre-incubation holding period. A significant positive correlation was found between temperature and embryonic mortality as well as relative humidity and embryonic mortality. The hatchability on fertile eggs was highest in crossbred ducks and almost similar in both Khaki Campbell and Indigenous ducks. The hatchability was higher in eggs stored for 3 days in comparison with that of 7 days pre-incubation holding period. A negative correlation was found between temperature and hatchability as well as humidity and hatchability. The normal ducklings hatched out from the eggs of Khaki Campbell ducks was highest followed by Indigenous and crossbred respectively. There was a negative correlation between temperature and normal ducklings hatched as well as relative humidity and normal ducklings hatched. The preincubation holding temperature and relative humidity had positive correlation with dead-in-shell.

• 한국보건간호학회지
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• 제13권1호
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• pp.114-127
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• 1999

In order to care the persons who are dying a nurse should first solve her / his own conflicts about death. and be aware of their own concepts of death and dying. In order to find out patient's spiritual needs and to give better spiritual nursing care. a nurse should know her / his own spiritual needs and be aware of their own concepts of spiritual nursing problems. To improve nurse's understanding towards death and dying and nurse's knowledge towards spiritual needs and spiritual nursing care. 14 weeks(two hours a week) spiritual nursing care education was given to 3th grade baccalaureate nursing college student. Before and after spiritual nursing care education. 30 items of prepared questionare focused on the attitudes toward death and dying was asked. Pre and post results are as follow ; 1. The dying patient's emotional and physical needs. There was no significant difference between pre and post educated groups. Both of the situations. they agreed upon$(69.64\%)$ that the dying patients have high emotional and physical needs to solve. 2. Telling the truth of dying process. There was no significant difference between pre educated group$(53.33\%)$ and post educated group$(55.95\%)$. 3. Attitudes of medical personnels. There was no significant difference between pre$(51.49\%)$ and post educated groups $(53.87\%)$. These responses indicate that nursing college student didn't have enough experiences on dying patients care. 4. General attitudes on death and dying. Number of nursing students who were thinking positively toward death and dying were Increased (pre $39.68\%$. post $45.44\%$) and who were thinking negatively toward death and dying were also decreased (pre $37.30\%$. post $33.93\%$). 5. Attitudes toward mechanical assistance for life-expanding of helpless patient. There was a significant difference between pre and post educated groups. About $34.13\%$ of them approved upon mechanical assistance for life and about $33.14\%$ of them disapproved. 6. Attitudes of family members of dying patient. There was no significant difference between pre and post educated groups. About $45.24\%$ of both groups, agreed upon that the family members feel annoyed with dying patients and about $22.42\%$ of both groups disagreed. Whether they received the spiritual nursing education or not, they were aware of that the family members feel annoyed with dying patients. 7. Special facility and educational preparation for dying patient. There was a significant difference between pre$(82.14\%)$ and post$(90.87\%)$ educated groups. These responses indicated that after they received the education, they felt more about the necessity of special facility and educational preparation for the death and dying patients. 8. Special facility and welfare system for the old. There was a significant difference between pre$(58.33\%)$ and post$70.64\%$ educated groups. There responses indicated that after they received the education, they felt more about the necessity of special facility and welfare systems for the old.

• 대한가정학회지
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• 제36권1호
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• pp.129-142
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• 1998

The purposes of this study were to identify education expenditure and to analyze contributing factors to total education expenditure for two children among married couples. For these purposes, total sample of 1,256 married couples those having two children of both pre-school aged and school aged were selected, and total sample was divided into four groups by first child's school aged; those were pre-school aged(375), elementary school aged(385), middle & high school aged(248) & college aged(248). Statistics used for the analysis were frequencies, means, percentile, and tobit and OLS analysis. The results were as follows. First, the households those having the first child of pre-school aged didn't spent for public education expenditure, while public education xpenditure of school aged increased continuously. The households having the first child of high school aged spent the most private education expenditure among four groups, however, total education expenditure of the households having the first child in college aged spent the most education expenditure were household head's age, family size, home ownership and financial asset amount, and elementary school-aged's factors were household head's age, education level, home ownership and total household income. Also, household head's education level, wife's expectation of future economy, residence, total household income had significant effects on total education expenditure in middle and high school-aged, and household head's job, home ownership, contact with neighborhood, residence and Engel's coefficient were significant variables in college aged.

• 생명과학회지
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• 제29권1호
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• pp.37-44
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• 2019

조릿대 잎은 항염, 해열, 이뇨작용 등의 약리효과를 가지고 있어 예로부터 전통의약에서 사용되어 왔다. 본 연구팀은 열수 추출한 후 남는 잔사로부터 식물화합물을 다량으로 함유한 잔사 추출물(PRE)을 제조하는 방법을 보고 바 있다. 본 연구는PRE의 고요산 혈증 저감소재로서 활용 가능성을 평가하기 위하여 수행하였다. Potassium oxonate(PO)로 유도한 고요산 혈증 생쥐 모델에서 PRE는 혈액 내의 요산, 요소 질소, 크레아틴 농도는 감소시켰고, 오줌 내의 요산과 크레아틴 농도는 증가하였다. 또한, PRE 투여한 고용산 혈증 생쥐에서 간 내 요산 농도와 xanthine oxidase 활성이 대조군에 비해 감소하였고, PRE는 PO에 의해 유도된 간 조직의 상해를 보호하였다. 이 결과는 PO로 유도된 고요산 혈증 생쥐에서 PRE는 항염증 및 세포보호 작용에 기인하는 것으로 판단된다. 부가적으로 PRE에 의한 신장조직에서 transcriptome의 반응 변화를 RNA 서열분석법으로 분석하였다. PRE는 주로 면역반응, 염증반응 및 대사과정에 관여하는 유전자의 발현에 영향을 미치는 것으로 나타났다. 본 연구 결과는 염증을 동반하는 고요산 혈증을 개선하는 소재로서의 PRE의 활용 가능성을 제시해 준다.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제26권1호
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• pp.19-30
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• 2023

This study analyzes the tasks selected and implemented by pre-service mathematics teachers to support students' development of epistemic actions. Data was collected from 20 students who participated in a mathematics education curriculum theory course during one semester, and multiple data sources were used to gather information about the microteaching sessions. The study focused on the tasks selected and demonstrated during microteaching by pre-service teachers. The results suggest that providing students with a variety of learning opportunities that engage them in different combinations of abductive and deductive epistemic actions is important. The tasks selected by pre-service teachers primarily focused on understanding concepts, calculation, and reasoning. However, the use of engineering tools may present challenges as it requires students to engage in two epistemic actions simultaneously. The study's findings can inform the development of more effective approaches to mathematics education and can guide the development of teacher training programs.

• 한국생활과학회지
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• 제10권1호
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• pp.73-82
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• 2001

The aim of this study is to provide the basic data for clothing construction of pre-school children by the result of the analyses and classifications of children's upper body somatotypes. The objects of this study are the bodies of 220 male pre-school children from 3 to 6 years old. The method of anthropometric measurement is the direct and photographic measurement. After analysing the measurements, 7 factors were extracted and the factors were applied to the cluster analysis. As the results, the 4 types were classified. Type 1 was characterized by the shortest and normal body one among these four types. This type showed the forward-curved back, the projected abdomen, and the fallen shoulders. Type 2 was characterized by the normal height and the fattest body type. Type 3 was characterized by the slimmest body and the shorter height type. Type 4 was characterized by the tallest and normal body with the rising shoulders.

• 대한영양사협회학술지
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• 제22권1호
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• pp.1-12
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• 2016

The purpose of this current study was to examine the effects of nutrition and food safety management support by the Center for Children's Foodservice Management (CCFSM) in foodservice facilities for children in the Ulsan area. From December 2014 to July 2015, the status of nutrition practices and hygiene practices was assessed by dietitians using nutrition and hygiene practice checklists. The subjects of study were 48 institutional foodservice facilities for children. Some nutrition practice items showed significant increases in average scores of 'using CCFSM menus (P<0.001), revising menus (P<0.05), and reconfirm menus (P<0.01)' from pre-support to post-support. Regarding hygiene practices, some items between pre-support to post-support showed significant increases in average scores of 'having equipment for hand washing & disinfecting' (P<0.01), 'wearing disinfected clothing for kitchen hygienically' (P<0.05), 'proper sterilization' (P<0.05), 'recording the origin of ingredients' (P<0.01), 'use of different knives/cutting boards' (P<0.05), and 'an appropriate thawing process' (P<0.05) from pre-support to post-support. Based on the above results, we found that nutrition and hygiene management support by CCFSM in foodservice facilities for children had a positive influence on status of some nutrition and food safety practices.

• 생명과학회지
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• 제28권6호
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• pp.738-744
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• 2018

제주조릿대는 한라산 일대에서 자생하는 제주특산식물이다. 예로부터 조릿대 잎은 다양한 약리효과를 가지고 있어 전통의약에서 사용되어 왔을 뿐만 아니라 최근에는 식품 및 화장품 소재로서 활용되고 있다. 우리 연구팀은 제주조릿대 잎의 효율적인 산업적 활용을 촉진하기 위하여 열수 추출한 후 남는 잔사로부터 식물화합물을 다량으로 함유한 잔사 추출물(PRE)을 제조하는 방법을 보고한 바 있다. 본 연구는 PRE 및 분획물이 항산화 혹은 항염소재로서 활용 가능성을 평가하기 위하여 수행하였다. PRE 에틸아세테이트 분획물(EPRE)은 DPPH, ABTS, superoxide 자유기 소거활성이 우수하였고, LPS로 자극한 RAW 264.7 세포에서 활성 산소종(ROS)과 nitric oxide (NO) 생성을 효과적으로 억제하였다. EPRE는 nuclear factor E2-related factor 2 (Nrf 2)의 핵내 이동을 증가시킴으로써 heme oxygenase-1 (HO-1)의 발현을 유도하였다. HO-1 저해제인 zinc protoporphyrin (ZPP)은 EPRE에 의한 NO 생성 저해 능을 감소시키기 때문에 HO-1이 NO 생성 억제에 관여함을 알 수 있었다. 본 연구결과는 PRE와 EPRE가 항산화 및 항염 소재로서의 활용 가능성을 제시해 준다.