• 대한치과보철학회지
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• 제44권4호
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• pp.432-442
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• 2006

Statement of problem: One of common problems associated with dental implant is the loosening of abutment screws that retain the implants. Purpose : This study was performed to investigate the influence of abutment screw length and repeated tightening on screw loosening in dental implant. Material and method: Forty nine Hexplants (13mm length, 4.3mm diameter, Ti grade IV, Warantec. Co. Ltd. Seongnam, Korea) and cementation type abutments(straight abutment) and abutment screws (0.4mm/pitch) were divided into 7 groups, depending on abutment screw length. Each implant and abutment was tightened to 30Ncm by torque controller(MGT50, MARK-10 Inc., USA) and the removal torque values were measured during 10 consecutive closure/opening trials. Results and Conclusion: The results of comparing the removal torque value are as follows : 1. There is no significant difference in the removal torque value between groups in 10 consecutive closure/opening trials (p = 0.97). 2. If the fractured abutment screw is engaged in longer than 2.425 thread length, there is no significant difference in the preload between the fractured abutment screw and the new abutment screw when both are equally tightened to 30 Ncm. 3. The removal torque value in the 1st trial(24.510 Ncm) was lower than that in the 2nd, 3rd, 4th, 5th, 6th, 7th trials and the removal torque value in the 2nd trials(25.551 Ncm) was maximum and was decreased in 1311owing trials. The removal torque value in the 1st trial was significantly lower than that in the 2nd, 3rd, 4th trials and was significantly higher than that in the 8th, 9th, l0th trials(p<0.05). 4. In the 2nd, 3rd, 4th, 5th, 6th, 7th trials, the abutment screw was mainly influenced by settling effect and the higher preload was obtained In the 8th, 9th, l0th trials, the abutment screw was mainly influenced by adhesive wear and the progressively lower preload was obtained.

• 한국정보처리학회논문지
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• 제4권7호
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• pp.1749-1758
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• 1997

전력수요의 예측은 예측기간에 따라 중장기 전력수요 예측과 단기 부하 예측으로 구분할 수 있다. 기존의 단기 부하예측은 주로 역전파 알고리즘(back propagation algorithm)다층퍼셉트론을 이용하여 예측을 하였으나 이는 학습시간이 많이 걸릴 뿐만 아니라 학습도중에 지역최소점(local minima)에 빠져 학습이 계속되지 못한다는 문제가 있다. 본 논문은 이러한 역전파 알고리즘의 문제점을 해결할 수 있는 방법으로 Radial Basis 함수(Radial Basis Function)를 이용하여 동적 단기부하 예측 모형을 제안한다. Radial Basis 함수는 하나의 은닉층(hidden layer)을 갖고 있으며, 전방향(feed-forward)학습을 한다는 특징이 있다. 본 논문에서 제안한 단기 부하 예측모형은 학습을 하기 위하여 시간대별 부하량을 클러스터링 하고, 이 클러스터의 중심값을 Radial Basis 함수의 은닉층으로 하여 학습을 한 다음 예측하고자 하는 패턴을 한 단위로 하여 시단대별로 예측하였다. 기존의 연구에서의 클러스터링 방법으로는 통계학의 K-Means 방법이나 Kohonen의 LVQ(Learning Vector Quantization)을 주로 이용하였으나 본 논문에서는 패턴의 분류에 있어서 다른 알고리즘보다 편차가 작은 Pal, et. al.의 GLVQ(Generalized LVQ) 알고리즘을 이용하였다. 본 논문에서 이용한 데이타는 1995년 3월 1일-3일, 6월 1일-3일, 7월 1일-3일, 9월 1일-3일, 11월 1일-3일의 72시간 데이타를 입력하여 월별 4일의 24시간의 예측시간으로 예측하였다. 실험결과 월별 1일과 3일까지의 학습데이타로 1시간 후의 부하량을 24시간동안 예측한 결과 1.3795%의 평균 오차율로 예측하였다.

• 한국식품영양학회지
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• 제24권4호
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• pp.535-550
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• 2011

The purpose of this study was to investigate changes in the cooking process of $Bibimbab$(cooked rice mixed with various ingredients) appeared in cook books published after Korean modern era, approximately from late 19th century to the present. 7 cook books were chosen to be analyzed. It is found that the ingredients were mixed with the rice before being served in the cook books written in late 19th century until mid 20th century, while the ingredients were separately decorated on top of the rice in the cook books written from mid 20th century until late 20th century. $Gochujang$(Korean chilly paste), which is common spicy seasoning for $Bibimbab$ in the present time, appeared only in $Hangukeumak$(1987) which is written in late 20th century. Prior to $Hangukeumak$(1987), chilly powder or chilly was used for chilly-based spicy seasoning. Cook books written in late 19th century until mid 20th century, ingredients used for $Bibimbab$ had complicated cooking methods such as $Jeonyueo$(assorted pan-fried delicacies), $Nurumi$(fried beef skewer with various vegetables) and $Sanjeok$(grilled beef skewer). From mid 20th century until late 20th century, among the cook books analyzed in this research, only $Hankukyoribaekguasajeon$(1976) suggested $Jeonyueo$ as an ingredient, and in general, the cooking method for preparing beef became simpler. For further studies, firstly, the cooking procedures used for $Bibimbab$ in the prior period to the Korean modern era need to be examined for more information about the changes of cooking style of $Bibimbab$. Secondly, new $Bibimbab$ recipes for modern restaurants could be created by using the recipes used in the historical cook books. Finally, the definitions of culinary terms used in historical cook books need to be clarified.

• Environmental Analysis Health and Toxicology
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• 제17권4호
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• pp.325-332
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• 2002

A helper T(Th)1-mediated response is known to enhance cell -mediated immunity, while a Th2-mediated response is associated with the humoral immunity that if elevated IgE levels and eosinophilia. Prostaglandin (PG)E$_2$results in the decreased capability of Iymphocytes to produce Thl cytokines, with a shift toward a Th2 cytokine response. Chlorpyrifos (CPF) has been reported to impair the blastogenesis and response of T Iymphocytes. CPF also induces delayed febrile effects, which results from the activation of COX -PGE$_2$pathway. The purpose of this study is to determine the effort of CPF on the in vitro production of Th cytokines and the role of PGE$_2$on the CPF-induced production of Th cytokines. Splenocytes obtained from male BALB/c mice were pretreated with CPF(0.1, 1, 10 and 100$\mu$M) in the presence of absence of indomethacin or PGE$_2$for 12 h and then were incubated with concanavalin (Con) A for 48 h. These results showed that CPF remarkedly reduced the production of splenic interleukin (IL)-2 and interferon (IFN)-γ in a dose-dependent manner. CPF significantly increased the splenic IL-4 production at low doses (0.1 and 1$\mu$M) but did not affect at high doses (10 and 100 $\mu$M). Indomethacin reduced the CPF-decreased production of IL-2 and IFN-γ in a dose -dependent manner and significantly attenuated the production of IL-4 increased by CPF 0.1 $\mu$M. High dose of CPF significantly reduced the PGE$_2$-decreased production of IL-2 and IFN-γ, while the PGE$_2$- induced production of IL-4 was significantly enhanced by CPF 1 $\mu$M. These findings suggest that CPF nay down-regulate the immune response of Th 1 type by the suppressed production of IL-2 and IFN-γ, with a shift toward a Th2 cytokine response. The CPF-decreased production of Thl cytokines may not be mediated by endogenous PGE$_2$. Also, CPF may attenuate the exogenous PGE$_2$-decreased Th 1 immune response in a dose--dependent manner but may affect dose-independently the PGE$_2$-induced Th2 immune response.

• 한국초지조사료학회지
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• 제23권2호
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• pp.101-106
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• 2003

본 연구는 오차드그라스 종자생산을 위한 적정 파종시기를 구명하기 위하여 축산기술연구소 초지사료과 시험포장에서 2001년부터 2002년까지 실시되었다. 공시품종은 국내에서 육성한 오차드그라스 "합성2호"로 하였다. 처리내용은 파종시기로 8월 10, 20, 30일과 9월 10, 20, 30일에 하였다. 시험구 배치는 난괴법 3반복으로 하였다. 정착상태는 8월 10일 파종에서는 늦 장마로 인하여 유모의 정착이 불량하였다. 수량구성요소 중 단위면적당 이삭수는 8월 20일 파종에서 $265/\textrm{m}^2$로 가장 많았고, 파종기가 늦을수록 이삭수가 줄었으며, 9월 20일 이후 파종은 출수경이 거의 없었다. 수량구성요소들은 8월 20일 파종 이후부터 파종기가 늦어질수록 점차 불량하였다. 그에 따라서 종자수량도 8월 20일 파종에서 759kg/ha로 가장 많았고, 파종이 늦어질수록 유의적으로 감소하였다.적으로 감소하였다.

• 대한한방내과학회지
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• 제30권3호
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• pp.451-464
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• 2009

Background and Objective : Cyperus rotundus L. (CR) is a commonly used herbal medicine in Asian countries such as Korea, China and Japan. The present study was designated to evaluate the direct effects of CR on helper T cell activities and on Th1/Th2 lineage development in vitro. Materials and Methods : Spleen cells from 8 week BALB/c mice were cultured in CR extracts containing medium without activation for 24 hours and with activation for 48 hours. CD4+ T cells were isolated and analyzed for mRNA expression levels of INF-$\gamma$, IL-4, T-bet and GATA-3 by RT-PCR and secretion cytokines levels of INF-$\gamma$, IL-4, IL-5 and IL-10 by ELISA. Results : The results demonstrated that CR had no mitogenic effects on unstimulated CD4+ T cells, but augmented CD4+ T-cell proliferation upon activation with anti-CD3/anti-CD28 antibodies in a dose-dependent manner. CR treatment significantly increased CD4+ T cell population and the IFN-$\gamma$ expression was significantly enhanced, while IL-4 expression was significantly decreased. In addition, in vitro Th1/Th2 polarization experiments revealed that CR enhanced IFN-$\gamma$ secretion in Th1 cells, but reduced the IL-4 in Th2 cells in a dose-dependent manner. Conclusion : These results suggest that CR treatment could be a desirable alternative therapy for the prevention or correction of Th2 dominant pathological disorders, such as allergy and asthma.

• The Journal of Korean Physical Therapy
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• 제18권2호
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• pp.47-58
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• 2006

Purpose: The study to pulsed ultrasound effects of diabetes mellitus fracture model in rat. Methods: We used 36 Sprague-Dawely rats which were divided into 3 groups; the animals were divided into group of 4 rats each 4th, 14th and 28th days. All animal was induced diabetes mellitus model to used streptozotocin with 45 mg/kg. Pulsed wave were divided into $50\;mW/cm^2$ and $100\;mW/cm^2$. Results: T-ALP value was significantly change from group II, III on 14th, 28th days (p<0.05). Especially T-ALP value to between groups was significantly change from group II on 14th days (p<0.05). Osteocalcin value was significantly change from group II on 28th days(p<0.05). At fracture site, osteoblast, osteoclast expression was observed from 4th days after treatment and it reached its maximum intensity at 28th days. At fracture site, $TGF-{\beta}_1$ expression was observed from 4th days after treatment and it reached maximum intensity at 14th days. Conclusion: According to this study, diabetes mellitus fracture model to the more effective is divided into $50m\;W/cm^2$ pulsed ultrasound.

• Nutrition Research and Practice
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• 제4권4호
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• pp.270-275
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• 2010

Catecholamines are among the first molecules that displayed a kind of response to prolonged or repeated stress. It is well established that long-term stress leads to the induction of catecholamine biosynthetic enzymes such as tyrosine hydroxylase (TH) and dopamine ${\beta}$-hydroxylase (DBH) in adrenal medulla. The aim of the present study was to evaluate the effects of ginseng on TH and DBH mRNA expression. Repeated (2 h daily, 14 days) immobilization stress resulted in a significant increase of TH and DBH mRNA levels in rat adrenal medulla. However, ginseng treatment reversed the stress-induced increase of TH and DBH mRNA expression in the immobilization-stressed rats. Nicotine as a ligand of the nicotinic acetylcholine receptor (nAChR) in adrenal medulla stimulates catecholamine secretion and activates TH and DBH gene expression. Nicotine treatment increased mRNA levels of TH and DBH by 3.3- and 3.1-fold in PC12 cells. The ginseng total saponin exhibited a significant reversal in the nicotine-induced increase of TH and DBH mRNA expression, decreasing the mRNA levels of TH and DBH by 57.2% and 48.9%, respectively in PC12 cells. In conclusion, immobilization stress induced catecholamine biosynthetic enzymes gene expression, while ginseng appeared to restore homeostasis via suppression of TH and DBH gene expression. In part, the regulatory activity in the TH and DBH gene expression of ginseng may account for the anti-stress action produced by ginseng.

• 한국의류산업학회지
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• 제8권4호
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• pp.413-419
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• 2006

This study was performed to analyze the wearing practice and the purchasing characteristics of jeans in order to offer basic data to produce superior jeans made of denim with small flexibility and to improve the wearing comfort. The questionnaire were 236 Korean women from the age of 10th to 50th. For data analysis, descriptive analysis and crosstabs were used. The results were as follows, in the purchasing characteristics, when the women of 10th to 30th decided to purchase jeans they considered fashion, design and price rather than wearing comfort. But the women of 40th to 50th considered that wearing comfort is the most important factor. The 10th is found the best preferred jean is wide straight style, the 20th is straight style, the 30th is boots cut style and the 40th to 50th is straight style. In wearing practice, there was a difference among age groups on the region that felt uncomfortable when wearing jeans. As the age increases, the abdomen size also increases. Most people answered that they mend jeans after purchase for length, without any relation with age. The reason why consumers prefer jeans with middle length between the crotch and waist and also purchase jeans with a short length is because they look refined and neat. This informs us that the short length between the crotch and waist does not match with ease and comfort, which are the images of jeans in the past. Recently premium jean brands are competing to show Low Rise Jeans, which seems like a Premium Jean=Low Rise Jean formula is created. Some manufacture companies are recklessly copying foreign designs that does not fit Korean's body shape. However, as mentioned in this study results, there is a clear difference between designs that they think consider as aesthetic and functional. Therefore, it is considered necessary for developing designs for jeans that can satisfy both aesthetic appreciation and functions for Korean consumer's body shape and each age group.

• 한국의류산업학회지
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• 제11권4호
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• pp.592-601
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• 2009

This study was conducted to find out the purchasing characteristics, the wearing practices and the preferring style of skirts. Also the comparison between recognized body type and actual body type for skirt was analyzed. The questionnaire was developed and administered to 179 women aged 20 to 59 in Busan. The women of 20th liked to buy skirts at the road shops and the internet shops but the 30th, 40th and 50th at the department stores and the discount stores. The main purpose of buying skirts was to coordinate with other clothes. The design of skirt was the most important factor of buying. The women of the 20th wore skirts without special purpose but the 30th, 40th and 50th wore those for social life. The women of the 20th liked to wear skirts with t-shirts and cardigan, the 30th with blouse and cardigan and 40~50th with blouse and jacket. As the age increased, the ratio of women who felt discomfort of skirts increased. Most of these women felt discomforts in the waist and abdomen part of skirt. The style of skirt that made up for the weak points in the body type was preferred. The preferred silhouettes of skirts were semi-tight and A-line. The preferred lengths of skirts were different from ages. Black was preferred color of skirts. There was a significant difference in recognized body type according to age groups. As the age increased, the ratio of women who thought themselves as thick waist type increased. Just only 43% women of total subjects recognized their body type accurately.