• 한국소음진동공학회논문집
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• 제22권12호
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• pp.1243-1249
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• 2012

이 논문에서 유한요소 모형은 2단계로 개선된다. 첫 단계에서는 감쇠를 무시하고, 최적화 방법을 사용하여 유한요소 모형의 질량행렬과 강성행렬을 개선한다. 최적화를 위한 목적함수는 모드시험 데이터와 유한요소해석으로부터 구한 고유진동수와 진동형으로 이루어져 있다. 두 번째 단계에서는 첫 단계에서 구한 질량행렬과 강성행렬을 고정시키고, 감쇠를 고려한다. 먼저 비례감쇠를 가정하고 감쇠행렬을 추정한 다음, 해석적인 주파수응답함수와 측정한 주파수응답함수의 차가 최소가 되도록 최적화 과정을 이용하여 감쇠행렬을 조정한다. 이와 같은 모형개선 방법을 시뮬레이션 계와 실제 외팔보에 적용하였다.

• 동의신경정신과학회지
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• 제24권3호
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• pp.271-280
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• 2013

Objectives : The development of natural drugs with antidepressant effects is important and needed. This study was performed to investigate the antidepressant-like effects of the distilled water extract of Portulaca oleracea L. (POL) in a mouse model and to investigate the role of ${\alpha}$-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptors in producing these antidepressant-like effects. Methods : The forced swim test (FST) and tail suspension test (TST) were used to investigate the behavioral anti-depressive-like effects of POL in mice. Additional behavioral experiments with 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo[f]quinoxaline-2,3-dione, an AMPA receptor antagonist, were undertaken to determine the involvement of the antidepressant-like properties of POL in AMPA receptor throughput. Results : Oral administration of the POL extract (100 mg/kg) 1 h prior to testing significantly reduced the immobility times in the FST and TST. The antidepressant-like effects of the POL extract were not increased in a dose-dependent manner. Pre-treatment with NBQX significantly attenuated the reduction in immobility time induced by the POL extract in the FST. Conclusions : The distilled water extract of POL has antidepressant-like effects, which may be related to AMPA receptor. Pre-treatment with NBQX significantly attenuates the reduction in immobility time induced by the POL extract in the FST.

• 동의생리병리학회지
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• 제27권2호
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• pp.233-238
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• 2013

The development of healthy beverages are increasing by big concerns for well-being. The aim of this study is to develop cultivated wild ginseng-Kyungohkgo (CKOG) beverage using cultivated wild ginseng instead of natural wild ginseng for Kyungohkgo. To examine physiochemical properties of CKOG beverage, pH, degree Brix, acidity, Huntor color, particle size and sedimentation volume were measured. When compared with commercial KOG beverage, CKOG beverage was lower in pH, acidity, particle size and higher in sedimentation volume. In the sensory evaluation of CKOG beverage, the best recipe of healthy CKOG beverage was 20% CKOG, 5.7% honey, 0.2% citric acid and 74.1% of water. In stability testing, pH, degree Brix, acidity, Huntor color of CKOG beverage was not changed, microbes in CKOG beverage was not detected for 60 days. These results suggest that CKOG may have a possibility of development as healthy beverage.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2765-2770
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• 2012

Background: There is a long standing interest in the identification of medicinal plants and derived natural products for developing cancer therapeutics. Here we investigated the antiproliferative properties of Melissa officinalis (MO) from Turkey on breast cancer. Methods: MO extracts were studied for cytotoxicity against breast cancer cell lines (MCF-7, MDA-MB-468 and MDA-MB-231). In vitro apoptosis studies were performed by annexin V staining and flow cytometry analyses. Immunohistochemistry for Ki-67 and caspase 7 in the tumoral tissue sections of DMBA-induced mammary tumors in rats was also performed, along with TUNEL assays to detect apoptotic cells. In vivo anticancer activity testing was carried out with reference to inhibition of growth of DMBA induced mammary tumors in rats. Results: MO showed cytotoxicity against three cancer cell lines, inducing increase in Annexin-positive cells. Expression of caspase-7 protein and TUNEL positive cells were much higher in rats treated by MO, compared with the untreated control group, while expression of Ki-67 was decreased. Furthermore, in vivo studies showed that mean tumor volume inhibition ratio in MO treated group was 40% compared with the untreated rats. Conclusion: These results indicated that MO extrcts have antitumoral potential against breast cancer.

• Journal of Ginseng Research
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• 제42권2호
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• pp.175-182
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• 2018

Background: The impact of fungicide azoxystrobin, applied as foliar spray, on the physiological and biochemical indices and ginsenoside contents of ginseng was studied in ginseng (Panax ginseng Mey. cv. "Ermaya") under natural environmental conditions. Different concentrations of 25% azoxystrobin SC (150 g a.i./ha and 225 g a.i./ha) on ginseng plants were sprayed three times, and the changes in physiological and biochemical indices and ginsenoside contents of ginseng leaves were tested. Methods: Physiological and biochemical indices were measured using a spectrophotometer (Shimadzu UV-2450). Every index was determined three times per replication. Extracts of ginsenosides were analyzed by HPLC (Shimadzu LC20-AB) utilizing a GL-Wondasil $C_{18}$ column. Results: Chlorophyll and soluble protein contents were significantly (p = 0.05) increased compared with the control by the application of azoxystrobin. Additionally, activities of superoxide dismutase, catalase, ascorbate peroxidase, peroxidase, and ginsenoside contents in azoxystrobin-treated plants were improved, and malondialdehyde content and $O_2^-$ contents were reduced effectively. Azoxystrobin treatments to ginseng plants at all growth stages suggested that the azoxystrobin-induced delay of senescence was due to an enhanced antioxidant enzyme activity protecting the plants from harmful active oxygen species. When the dose of azoxystrobin was 225 g a.i./ha, the effect was more significant. Conclusion: This work suggested that azoxystrobin played a role in delaying senescence by changing physiological and biochemical indices and improving ginsenoside contents in ginseng leaves.

• 대한조선학회논문집
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• 제54권1호
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• pp.43-48
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• 2017

In recent years, the demand for ships and offshore platforms that can navigate and operate through the Arctic Ocean has been rapidly increasing due to global warming and large reservoirs of oil and natural gas in the area. Winterization design is one of the key issues to consider in the robust structural safety design and building of ships that operate in the Arctic and Sub-Arctic regions. However, international regulations for winterization design in Arctic condition regulated that only those ships and offshore platforms with a Polar Class designation and/or an alternative standard. In order to cope with the rising demand for operating in the Arctic region, existing and new Arctic vessels with a Polar Class designation are lacking to cover for adequate winterization design with HSE philosophy. Existing ships and offshore platform was not designed based on reliable data based on numerical and experiment studies. There are only designed as a performance and functional purposes. It is very important to obtain of reliable data and provide of design guidance of the anti-icing structures by taking the effects of low temperature into consideration. Therefore, the main objective of this paper reconsiders anti-icing design of aluminum helideck using the heating cable. To evaluate of reliable data and recommend of anti-icing design method, various types of analysis and methods can be applied in general. In the present study, finite element method carried out the thermal analysis with cold chamber testing for performance and capacity of heating cables.

• 한국정보시스템학회지:정보시스템연구
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• 제13권2호
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• pp.22-48
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• 2004

Information systems that are not used cannot be useful. In order to increase user acceptance, it is necessary to understand why people accept or reject information systems. Technology Acceptance Model(TAM) is one of the most influential research models for studying determinants how users accept information systems. Recently, Knowledge Management Systems(KMS) have become important components of corporate systems as the foundation of industrialized economics has shifted from natural resources to knowledge assets. This paper applies TAM to investigate users' acceptance of KMS in public administration institutions. It sampled 182 users who had experience in using KMS. Many empirical researches have suggested that TAM can be integrated with other organizational theories to improve its predictive and explanatory ower. We extended the basic TAM by the integration of appraisal and reward satisfaction theory. There are many external variables that influence the perception and the belief of system users. We introduced two external variables(job characteristics, IT self-efficacy) and one additional perception variable, perceived appraisal and reward(PAR) in the basic TAM model. The LISREL model analysis is used for finding out the causality among variables and testing the model fitness. As result, The IT self-efficacy influences to the perceived ease of use(PEOU) and the PAR, and the PEOU influences directly to the perceived usefulness(PU), the PAR, and the attitude toward KMS. The KMS participation intention(PI) was influenced by the PAR and the attitude directly,andbythePEOUindirectly. Finally, this paper suggests some guidelines for the adoption of KMS in public sectors on the basis of the study results.

• 환경정책연구
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• 제11권2호
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• pp.55-71
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• 2012

화석연료를 중심으로 한 에너지 가격의 상승 추세가 이산화탄소 배출의 자연스러운 감축에 미치는 영향을 파악해 보기 위해, 본 논문은 일인당 이산화탄소 배출량의 에너지 가격에 대한 탄력성을 추정하고자 한다. 이를 위해 OECD 29개국의 1978년에서 2009년까지의 패널 자료를 구축하였으며, 환경 쿠즈네츠 가설을 검증하기 위한 추정 모형을 이용하였다. 추정 결과, 실질 에너지 가격지수가 1% 상승할 때, 일인당 이산화탄소 배출량은 0.26 ~ 0.31% 가량 통계적으로 유의하게 감소하는 것으로 나타났으며, 이러한 탄력성의 크기는 이산화탄소 배출량의 감축 목표 설정에 있어 서 향후 예상되는 에너지 가격의 지속적 상승의 영향을 감안해야 함을 시사한다. 아울러 에너지 가격 변화의 영향을 고려하여 추정된 환경 쿠즈네츠 곡선의 존재 역시 강건하고 유의하게 확인되었으며, 그 소득 전환점은 모형설정에 따라 22,200 ~ 48,500달러의 범위에 놓이는 것으로 나타나고 있다.

• 한국전문물리치료학회지
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• 제22권1호
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• pp.9-18
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• 2015

This study aimed to compare the characteristics of breast cancer surgery and shoulder surgery patients on the shoulder range of motion (ROM), degree of pain and dysfunction, and scapular position. This study was carried out with a total of 90 women: a breast cancer surgery group (BS, $n_1=30$), a shoulder surgery group (SS, $n_2=30$) and a control group ($n_3=30$). Shoulder ROM, the Quadruple Visual Analogue Scale (QVAS), the Shoulder Pain and Disability Index (SPADI), and the Scapular Index (SI) were used to assess shoulder function. Statistical analyses were performed using a one-way analysis of variance, crosstab test, and independent sample t-test. Post-hoc testing was carried out with Bonferroni test. There were significant differences in shoulder ROM when the BS and the SS were compared with the control group. However, there was no significant difference in ROM between the BS and SS. Furthermore, there was a significant difference in shoulder pain between both surgery groups, and there was greater shoulder dysfunction in the SS than in the BS. There was also a significant difference in upper extremity posture when the BS and the SS were compared to the control group. Finally, there was no significant difference in upper extremity posture between the BS and the SS. This study compared shoulder ROM, pain, dysfunction, and upper extremity postures between the BS and SS. While there were no significant differences in shoulder ROM, pain, and upper extremity posture between both surgery groups, the level of dysfunction was found to be significantly different. Therefore, health professionals managing for breast cancer surgery or shoulder surgery patients should consider these outcomes.

• 한국지반환경공학회 논문집
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• 제10권2호
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• pp.61-68
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• 2009

본 논문은 수리학적 현장 주입시험 기간 동안 고려될 필요가 있는 수리역학적 상호작용에 따른 균열암반매질의 수리학적 거동에 대한 수치적 연구이다. 이러한 주입시험은 굴착정 내에 설치된 개구간(open hole section)을 따라 높은 압력을 가진 유량을 주입하며, 이를 통해 굴착정을 가로지르는 균열로부터 유량을 측정하는 것이다. 시간에 따라 변화되는 유량측정결과는 수리역학적 상호작용에 대한 분석 및 예측을 위해 개발된 수치모형의 현장 적용성을 평가하기 위해 사용되었다. 유량측정결과 전도성이 있는 균열들은 상호의존적인 균열망을 형성하며, 이로 인해 균열망을 구성하는 개별적인 균열요소들은 독립적인 시스템으로서 적절하게 모형화 될 수 없음을 보여주었다. 또한 간극수압이 굴착정 주위에 작용하는 최소주응력을 초과할 때 새로운 유체유입영역이 발생되며, 이러한 최소주응력보다 훨씬 큰 간극수압은 굴착정 주위의 균열들에 의해 유지될 수 있다는 것을 보여주었다. 본 연구에서 이러한 특성들이 자연 상태의 균열망의 구성형태에 따라 어떻게 영향을 미치게 되는지 이산 균열망 모형을 통해 수치적으로 분석되었다.