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        검색결과 2,510

        661.
        2016.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 국제원유시장과 아시아 주식시장(한국, 중국, 일본, 인도, 인도네시아, 필리핀, 말레이시아, 태국, 대만, 싱가포르, 베트남)간의 상관관계를 국면전환 관점에서 분석한다. 이를 위해 유가와 주가지수 간의 시간가 변 상관계수를 DCC-GARCH(1,1) 모형으로 추정하였고, 비선형 시계열 분석기법인 Smooth Transition Regression(STR) 모형을 활용해 구조적 변화의 비선형 특성과 상관관계의 강도를 파악하였다. 2002년 1월부 터 2016년 3월까지의 자료를 토대로 한 분석 결과, 국제유가와 아시아 주가지수간의 상관관계는 시간의 흐름에 따라 그리고 국가별로 상이한 움직임을 나타냈다. 또한 상관관계의 국면간 전환점과 전환속도를 측정하는 모수가 일부 국가에서 유의하게 추정되었다. 이러한 결과는 원유와 아시아 국가 주식으로 포트폴리오를 구성할 경우 상 관계수의 추정과정에서 비선형성과 강도를 고려해야 할 필요가 있음을 시사한다. 이에 본 논문은 방법론적으로 기존의 국제재무 문헌의 확장에 기여하며 주식시장과 원유시장의 관계자들에게도 포트폴리오 구성 및 시장예측과 관련한 실무적 시사점도 제공한다.
        6,000원
        664.
        2016.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Losing balance during locomotive actions becomes an increasing threat to both the community-dwelling elderly and elderly with Parkinson disease (PD). Those with PD may be at a high risk of fall due to particular characteristics during the turn. Turning around during locomotive actions may be one of problematic factors causing losing balance. Objects: This study is part of a larger study, which in part aims to identify turning strategies, to compare the strategies in the elderly with and without idiopathic PD aged 51 years and older and to distinguish whether the turning strategies can predict the elderly at risk of falls. Methods: A total of 22 community-dwelling elderlies (10 elderlies with idiopathic PD and 12 healthy elderlies) were investigated for the turning strategies during the timed up and go test. Results: There were some significant differences between the two groups during turning (p<.05). The idiopathic PD group had a tendency of challenging on taking more number of steps, more time to accomplish and staggering more for the turn relative to the control group. Conclusion: Taking more number of steps and more time to turn may be useful for distinguishing the characteristics of PD from that of the healthy elderly in turning strategy.
        4,000원
        665.
        2016.11 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Deficiencies in the ability to maintain balance are common in elderly. Augmented feedback such as knowledge of results (KR) can accelerate learning and mastering a motor skill in older people. Objects: We designed this study to examine whether one session of Wii-Fit game with self-regulated KR is effective for elderly people, and to compare the effect of two different timings of self-regulated KR conditions. Methods: Thirty-nine community-dwelling elders, not living in hospice care or a nursing home, participated in this study. During acquisition, two groups of volunteers were trained in 10 blocks of a dynamic balancing task under the following 2 conditions, respectively: (a) a pre-trial self-regulated KR (n1=18), or (b) a post-trial self-regulated KR (n2=21). Immediate retention tests and delayed retention tests of balancing performance were administered in 15 minutes and 24 hours following acquisition period, respectively. Results: In both groups, significant improvements of balancing performances scores were observed during the acquisition period. Regardless of the group, mean of balancing performance scores on retention tests were well-maintained from the final session. There were no significant differences between groups in balancing performance scores during the acquisition period (p>.05); however, the post-trial self-regulated KR group exhibited significantly higher balancing performance scores in both the immediate retention test and delayed retention test than that of the pre-trial self-regulated KR group (p<.05). Conclusion: Therefore, subjects who regulated their feedback after a dynamic balancing task, during the acquisition period, experienced more efficient motor learning during the retention period than did subjects who regulated their feedback before a dynamic balancing task. Accordingly, in case of presenting the KR of motor learning in clinical settings to elders who reduced dynamic balance abilities, the requesting time of KR is imperative according to self-estimation processes as well as types of KR and practice.
        4,200원
        666.
        2016.11 구독 인증기관·개인회원 무료
        PVDF Membrane has been used as material for the UF membrane through in-situ interfacial polymerization (IP) because of it’s outstanding properties such as high chemical resistance, thermal stability, and mechanical strength. In this study, surface morphology change of PVDF membrane was researched depending on evaporation time. 13% PVDF 6020 was used for casting and the evaporation time period was from 5s to 600s. The surface morphology of the membrane was investigated by scanning electron microscopy (SEM) and filtration was conducted in the cross flow method to evaluate the a performance of UF membrane. As a result, average pore size was increased with longer evaporation times which caused the decrease of rejection.
        671.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Pressure monitoring is expected to be expanded in a water distribution system according to accelerated development of smart water network management technologies caused by appearances of affordable digital infrastructures like computing, storage and bandwidth. However, the placement of pressure sensors has been determined by engineer’s technical decisions since there is no well-defined criteria for deciding a suitable location of pressure sensor. This study presents a placement method of pressure sensors based on the consideration of allowable error in calibrating water network analysis modeling. The proposed method is to find a minimum set of pressure sensors for achieving a reliable management of water transmissions main and increasing the efficiency of their real-time operation. In the case study in Y area’s transmission main, the proposed method shows equally distributed pressure sensors in terms of hydraulics. It is expected that the proposed method can be used to manage transmission mains stably and construct a robust real-time network analysis system as a minimal criteria.
        4,000원
        672.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        이 연구에서는 p-version 동적무한요소법을 도입함으로써 FE-IE 기법에 기반한 KIESSI-3D 프로그램의 속도향상에 역점 을 두었다. KIESSI-3D의 성능을 평가하기 위해 8가지 실규모 SSI 문제에 대한 수치해석을 수행하였다. 이를 위해 근역지반 모델의 반경( r0 )이 구조물기초 반경(R)의 1.2배, 1.5배, 3.0배인 KIESSI-3D 해석모델을 고려하였다. 또한 SASSI2010 프로그 램을 이용한 SSI 해석을 수행하였으며, 이 결과를 KIESI-3D에 의한 결과와 정확성 및 계산속도를 비교하였다. 수치해석 결 과, 인 KIESI-3D 모델을 사용하면 정확한 해석을 수행할 수 있음을 알 수 있었다. 계산속도 측면을 보면, 새로운 KIESSI-3D의 해석속도는 기존 KIESSI-3D에 비해 최대 25배 빠른 것으로 나타났다.
        4,300원
        673.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This research was conducted to evaluate quality changes in traditional Doenjang and manufactured Doenjang during a storage period of 8 weeks. Low-salt Doenjang and commercial Doenjang were purchased from different manufacturers and proximate analysis as well as changes in isoflavone, polyphenol, flavonoid contents of the samples were investigated using a mass spectrophotometer. The salinity of traditional Doenjang, low salt Doenjang, and commercial Doenjang were 13.2±1.15, 7.17±2.74, 10.67±0.35%, respectively and the salt concentrations of the soybean pastes did not change during storage. After 8 weeks at 35℃, chromatic values of all the paste samples decreased somewhat, with traditional Doenjang exhibiting fewer changes as compared to manufactured Doenjang. Amino acid nitrogen, acidity, microbial population all tended to increase with time, although some samples showed fluctuations during the test period. Moreover, the total isoflavone contents of traditional Doenjang increased with storage time while that of manufactured Doenjang tended to decrease. The isoflavone aglycone was shown to be the highest in traditional Doenjang, while isoflavone glycoside was abundant in manufactured Doenjang. Total flavonoid contents showed similar trends regardless of samples; initial contents of total flavonoid was 0.6 mg/g which increased to more than twice to 1.4 mg/g at the end of storage period. Composition profile of Doenjang extracts was analyzed using UPLC-Q-ToF
        4,000원
        674.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        선원들은 선박의 충돌, 침몰, 좌초 및 화재 등의 여러 가지 원인으로 긴급 피난을 감행해야 하는 경우가 많이 발생한다. 이러한 사고 발생 시 인명 생존율을 높이기 위해서는 피난시간 단축이 아주 중요한 요소이나 선박의 좁고 복잡한 구조는 신속한 피난에 장애 요소가 되고 있다. 또한, 선박은 해상에서 운항하는 특성으로 좋지 않은 바다 상태에서는 행동의 제약이 발생한다. 이 연구에서는 선원들의 피난시간을 증가 시킬 수 있는 요인을 확인하기 위해 현재 승선중인 선원들을 대상으로 다양한 실험을 실시하고 그 데이터를 정리하였다. 실험 시나리오는 선원들에게 피난 공간 구조를 설명한 후와 하지 않은 후로 구분하였으며 가시거리를 0 m, 3 m, 5 m으로 구분하여 피난 시간을 확인하였다. 그 결과 피난속도는 구조 설명 여부에 따른 영향은 크지 않았으나, 가시거리의 경우 5 m와 0 m 및 3 m는 최대 2.5 ~ 2.6배 차이가 있음을 알 수 있었다. 즉, 피난시간을 감소에 필요한 요인인 가시거리는 5 m 이상 확보가 중요한 요소임이 확인되었다. 향후 선박에 승객 및 선원들의 인명 생존율을 향상시키기 위해서 가시거리 확보를 위한 노력이 필요할 것이다.
        4,000원
        675.
        2016.10 구독 인증기관·개인회원 무료
        Recent research has suggested that the dietary protein:carbohydrate (P:C) balance is a critical determinant of fitness in insects. In this study, we examined the effects of dietary P:C balance on life-time reproductive success in the mealworm beetle, Tenebrio molitor. Both males and females lived the longest when fed on P:C 1:1 diet. Throughout their adult lives, females fed on P:C 1:1 diet laid significantly more eggs than those on nutritionally imbalanced diets (P:C 1:5 or 5:1). When given a choice, beetles regulated their intake of protein and carbohydrate to a ratio close to 1:1. Taken together, our results indicate the balanced intake of protein and carbohydrate maximizes life-time reproductive success in this species.
        676.
        2016.10 구독 인증기관·개인회원 무료
        There are many other detection methods for Bursaphelenchus xylophilus. However, Baermann funnel method, PCR-based methods, which are laborious and time consuming processes that are unsuitable to rapid diagnose the Pine Wilt Disease (PWD) on the field. For these reasons, the aim of our experiment is not only to apply field diagnostic for pine wood nematode (PWN) but also to reduce total time for detection PWN in the pine trees by loop-mediated isothermal amplification (LAMP) with phosphate (Pi)-induced coloration reaction which could be yes or no answer for detection of PWN has not required UV detector but it just could be discriminated by naked eyes within 30 min. Genomic DNA was directly extracted from pine wood chips by Wood Chips Direct Lysis procedure which can be used for LAMP only after simple dilution. Our results suggest that LAMP-Pi detection method, simple and rapid method for detection of PWN, could be applied to the field diagnostic for PWD.
        677.
        2016.10 구독 인증기관·개인회원 무료
        Divergence time estimation over a robust phylogeny is a prerequisite for understanding their evolutionary biology. Recent empirical studies have found that molecular dating analyses are critically affected by the number and temporal distribution of fossil calibration points (Yang & Yoder, 2003; Hug & Roger, 2007), the interpretation of relationships between fossil and extant taxa (Benton & Ayala, 2003; Donoghue & Benton, 2007), and how fossil constraints are treated (Magallón, 2004; Ho & Phillips, 2009). Confident dating thus requires multiple fossils that are securely identified and of sufficient age. We provide a list of lepidopteran fossils potentially useful for calibration points, and end on the perspective for dating the currently working phylogeny of Lepidoptera (Regier et al., 2013), using these fossils. In addition, we show microtomographic images for some lepidopteran fossils that we are currently working on.
        678.
        2016.10 구독 인증기관·개인회원 무료
        칠면조는 슈퍼 푸드 중 유일한 육류 식품으로 선정되어 칠면조의 육류 소비는 더욱 증대될 것으로 기대된다. 이 에 따라 식품 중 사용된 동물성 원료인 칠면조의 신속하고 정확한 판별법 개발이 요구된다. 본 연구에서는 칠면조 를 정확하고 민감하게 검출하기 위해 TaqMan® probe를 활용한 real-time PCR 방법을 개발하였다. 종 특이 primer와 probe는 미토콘드리아의 cytochrome b 유전자를 대상으로 개발하였고, 특이성은 총 19 종의 동물성 원료를 대상으 로 확인하였다. 개발된 검출법의 검출한계는 칠면조 DNA를 10 ng 으로 부터 10배씩 희석하여 확인한 결과 0.1 pg 이었고, 동물성 식품원료인 소와 닭에 칠면조를 50, 25, 5, 1, 0.1% 비율로 혼합하여 확인한 결과 0.1 %까지 검출되 었다.
        679.
        2016.10 구독 인증기관·개인회원 무료
        감자는 세계에서 4번째로 중요한 식량작물로 식품 및 사료로 이용되고 있다. 감자의 주요 소비형태는 일반식용 위주와 전분, 감자칩, 감자튀김 등 다양한 형태의 가공제품, 씨감자 형태로 사용한다. 또한 감자를 식품산업과 제지 산업에서 활용하기 위해 amylose 함량을 감소시키거나 acrylamide 생성을 줄인 유전자변형 감자가 개발되고 있다. 이 에 따라 우리나라의 경우 감자 가공품 수입이 많은 만큼 국내외 감자 제품에 대한 미승인 유전자변형 감자에 대한 검사법이 필요하다. International Service for the Acquisition of Agri-biotech Applications (ISAAA) 보고에 따르면 2016 년까지 45개의 GM 감자이벤트가 개발되었다. 이 중 우리나라는 식품의약품안전처로부터 4종의 GM 감자가 식품용 도로 승인되었다. 본 연구에서는 현재 미승인 유전자 감자 6개 이벤트에 대해 정성검사용 표준플라스미드 (pUC_GM potato A and B)를 제작하였으며, UDP-glucose pyrophosphorylase (UGPase) gene을 감자 내재유전자로 사용했다. 개발 된 표준플라스미드는 식품의약품안저처의 고시를 토대로 primers와 probes를 이용하여 Applied Biosystems ViiA7 real-time PCR system을 통해 정성분석을 수행하였다. 또한 검정한계치를 확인하기 위해 플라스미드를 100,000 - 10 copies까지 희석한 것을 주형으로 하여 real-time PCR을 진행하였다. 이와 같이 미승인 유전자변형 감자에 대한 정성 분석용 표준플라스미드가 개발되었으며 국내 미승인 유전자변형 감자에 대한 모니터링에 활용될 수 있을 것으로 기 대한다.
        680.
        2016.10 구독 인증기관·개인회원 무료
        A self-powered time-temperature indicator (TTI) was optimized to enhance the performance of the TTI by modifying a biofuel cell using different immobilization, redox mediators, and status of electrode. The performance of the TTI was measured by output voltage of the TTI. The enzymes and combinations of lacasse mediators (HBT (1-hydroxybenzotriazole), Rupy (Bis-(bipyridine)-(5-aminophenanthroline) ruthenium bis (hexafluorophosphate)), MB (Methylene blue), SDP (4,4- sulfonyldiphenol)) and glucose oxidase mediators (FA (Ferroceneboxaldehyde), DBQ(2,5-dihydroxybenzoquinone), HQS (8-hydroxyquinoline-5sulfonic acid hydrate), FHFP (Ferrocenium hexafluorophosphate)) were immobilized with stabilizers (pyrrole) on a glassy carbon electrode by electrodeposition by applying a square wave, cross-linking and physical immobilization. MWCNTs were used to modify glassy carbon electrodes. MWCNTs coated electrodes produced higher output voltage than uncoated electrodes. The optimum and stable performance of the self-powered TTI was that the output voltage of 64 mV and duration time was 3hr at 25°C, when the combination of Rupy, MB for laccase mediators and HQS, FHFP for glucose oxidase mediators were immobilized on MWCNTs coated electrodes by applying a square wave method. In the application, the concentrations of enzyme and glucose were adjusted to prolong the shelf-life of TTI at much lower output voltage.