• BMB Reports
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• 제40권6호
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• pp.944-951
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• 2007

3-Hydrogenkwadaphnin (3-HK) is a daphnane-type diterpene ester isolated from Dendrostellera lessertii (Thymelaeaceae) with high differentiation and apoptotic potency in leukemic cells without any measurable adverse effects on normal cells (Moosavi et al., 2005b). In this study, we report that 3-HK (12 nM) has the ability to cease proliferation, induce differentiation and apoptosis in chronic myelogenous leukemia (CML) K562 cell line. The treated cells lost erythroid properties and differentiated along the megakaryocytic lineage based on the morphological features apparent after Wright-Giemsa staining, DNA content analysis and the expression of cell surface marker glycoprotein IIb as analyzed by flow cytometry. Moreover, using Hoechst 33258 and Annexin V double staining indicated the occurrence of apoptosis among the treated cells. On the other hand, restoration of the depleted GTP pool size by exogenous addition of guanosine ($50{\mu}M$) reduced the effect of the drug regarding the extent of differentiation while no further enhancement of 3-HK effect was obtained by addition of exogenous hypoxanthine ($100{\mu}M$). These interesting results necessitate further investigation regarding the mechanism of action of this unique anti-leukemic agent.

• 대한안전경영과학회지
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• 제14권3호
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• pp.119-126
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• 2012

Recently, the breakdown of online banking servers and the leakage of customer information give rise to much concern about the security of information systems in financial and banking companies in Korea. The enforcement of security for information system becomes much more important issue than earlier. However, the security reinforcement of information system is restricted by a budget. In addition, the activities' cost to secure information system from threatening are under uncertain circumstances and should be established by a human decision maker who is basically uncertain and vague. Thus, making the budget for information system is exposed to any extent of the risk for these reasons. First, we introduce brief fuzzy set theory and fuzzy AHP (Analytic Hierarchy Process) methodology. Then, the cost elements that comprise yearly budget are presented and the priorities among the cost elements are calculated by fuzzy AHP. The cost elements that are exposed to risk are evaluated from the both perspectives of the risk impact and risk occurrence possibility which are expressed as linguistic terms. To get information on the risk profiles-pessimistic, most likely, and optimistic-for each cost element, the evaluation is accomplished and the result is presented. At last, the budget ranges-minimum, mode, maximum-for each cost element are estimated with the consideration of the risk profiles.

• 약학회지
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• 제45권4호
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• pp.366-377
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• 2001

Persistent organochlorine pesticides has been used intensively in agriculture for a long time. The occurrence of organochlorine pesticides in the environment and subsequently in parts of the food chains, results in the intake of these compounds by human and animal. The measurement of the levels of organochlorine pesticides in tissues or blood of human populations is a good marker in evaluating the extent of exposure and hazards. So, most countries have conducted initial monitoring programs to determine organochlorine pesticides and polychlorinated biphenyls in human tissues. But, in Korea, a few research has been reported. In this study, the legally prohibited organochlorines, such as, $\alpha$-BHC, $\beta$-BHC, ${\gamma}$-BHC, $\delta$-BHC, p,p'-DDT, p,p'-DDD, p,p'-DDE, endrin, dieldrin and aldrin were determined in human blood, brain, adipose tissue, kidney cortex and liver tissues collected at autopsy of 10 men and 10 women, 16~65 years of age. Almost all the organochlorine pesticides mentioned previously were determined in human tissue samples indicated that they have been widely distributed in Korean human body. No significant difference was found in the levels of organochlorine pesticides between sexes, districts and ages.

• 한국의류산업학회지
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• 제25권3호
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• pp.346-357
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• 2023

The purpose of this study is to develop clothing customized for dealing with patients with severe dementia. Based on the results of previous studies, The research patient clothing was designed to reduce the physical fatigue experienced by caregivers when dressing and undressing patients by changing the position and shape of the split in the patient's clothing. This study used qualitative and quantitative methods to measure the extent to which these modifications improved the ease of dressing and undressing the research patient. The research patient clothing was developed by moving the rear-center zipper to the side and changing the zipper from being half-open to fully open. Muscle energy consumption and fatigue generation were analyzed using EMG signals at the following sites: brachioradialis, biceps, triceps, anterior deltoid, medial deltoid, posterior deltoid, upper trapezius and erector spinae. Results indicated that the modified research patient clothing required less muscle energy and the occurrence of muscle fatigue decreased overall compared to traditional patient clothing. This was supported by the qualitative subjective evaluation, which revealed that dressing and undressing was easier with the modified clothing. In conclusion, repositioning of the back zipper to the side and the fully open slit shape significantly reduced caregiver fatigue when dressing and undressing patients.

• Smart Structures and Systems
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• 제5권1호
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• pp.81-94
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• 2009

A vibration-impedance-based monitoring method is proposed to predict the loss of prestress forces in prestressed concrete (PSC) girder bridges. Firstly, a global damage alarming algorithm using the change in frequency responses is formulated to detect the occurrence of damage in PSC girders. Secondly, a local damage detection algorithm using the change in electro-mechanical impedance features is selected to identify the prestress-loss in tendon and anchoring members. Thirdly, a prestress-loss prediction algorithm using the change in natural frequencies is selected to estimate the extent of prestress-loss in PSC girders. Finally, the feasibility of the proposed method is experimentally evaluated on a scaled PSC girder model for which acceleration responses and electro-mechanical impedances were measured for several damage scenarios of prestress-loss.

• 한국산업융합학회 논문집
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• 제21권6호
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• pp.345-354
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• 2018

It is conservative to say that lots of research is performed as measures to use UAV for application to the rapid spatial information and its application is faced with settlement stage to some extent. In addition, Korea Land and Geospatial Informatix Corporation autonomously produces work regulation which is applied to every kind of orders and National Geographic Information Institute (2018) has notified public surveying work instructions about unmanned aerial device for the rapid spatial information construction. The results acquired by UAV are comprised of contents about accuracy improvements for the orthophoto when reviewing pertinent regulations. The results acquired by UAV are comprised of contents about accuracy improvements for the orthophoto when reviewing pertinent regulations. As a result, it is known that error amount has been sharply increased from 400m separation distance, and this study proposes that cross flight is able to reduce irregular error occurrence as measures to acquire stable results.

• 한국전산구조공학회논문집
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• 제21권1호
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• pp.83-90
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• 2008

본 논문에서는 프리스트레스 콘크리트(PSC) 거더교의 긴장력 손실을 예측하기 위한 진동기반 모니터링 체계를 제안하였다. 제안한 체계는 긴장력 손실 경보 단계와 긴장력 손실 정도를 평가하는 단계로 구성하였다. 먼저, 긴장력 손실 경보를 위해 두 위치에서 취득된 주파수 응답의 변화를 사용하여 긴장력 손실의 발생을 모니터링하는 새로운 전역적 손상경보기법을 제안하였다. 제안된 기법은 응답신호의 파워스펙트럼만을 이용하기 때문에 별도의 모드해석과정 없이 실시간으로 손상경보가 가능하다. 다음으로, 긴장력 손실 정도를 평가하기 위하여 고유진동수의 변화로부터 긴장력의 상대적인 손실 정도를 평가할 수 있는 긴장력 손실 예측 기법을 선정하였다. 제안된 체계의 유용성을 축소 모형 PSC 거더에 대한 실험을 통해 평가하였다.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.286-294
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• 2017

The events at the Fukushima Daiichi Nuclear Power Station in March 2011 point out, among other matters, that concurrent accidents at multiple units of a site can occur in reality. Although site risk has been deterministically considered to some extent in nuclear power plant siting and design, potential occurrence of multi-unit accident sequences at a site was not investigated in sufficient detail thus far in the nuclear power community. Therefore, there is considerable worldwide interest and research effort directed toward multi-unit site risk assessment, especially in the countries with high-density nuclear-power-plant sites such as Korea. As the technique of probabilistic safety assessment (PSA) has been successfully applied to evaluate the risk associated with operation of nuclear power plants in the past several decades, the PSA having primarily focused on single-unit risks is now being extended to the multi-unit PSA. In this paper we first characterize the site risk with explicit consideration of the risk associated with spent fuel pools as well as the reactor risks. The status of multi-unit risk assessment is discussed next, followed by a description of the emerging issues relevant to the multi-unit risk evaluation from a practical standpoint.

• Journal of Korean Neurosurgical Society
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• 제50권2호
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• pp.75-80
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• 2011

Objective : Leukoaraiosis (LA) has been suggested to be related to the poor outcome or the occurrence of symptomatic intracerebral hemorrhage (sICH) after acute ischemic stroke. We retrospectively investigated the influences of LA on long-term outcome and the occurrence of sICH after thrombolysis in acute ischemic stroke (AIS). Methods : In this study, we recruited 164 patients with AIS and magnetic resonance image (MRI)-detected thrombolysis. The presence and extent of LA were assessed using the Fazekas grading system. The National Institutes of Health Stroke Scale score was used to assess the baseline measure of neurologic severity, and the modified Rankin Scale score assessment was used up to 1 year after thrombolysis. Results : Of 164 subjects, 56 (34.2%) showed LA on MRI. Compared to the 108 patients without LA, the patients with LA were of much older age (p<0.01), had a higher prevalence of hypertension (p<0.01), and had a much poorer outcome at 90 days (p=0.05) and 1 yr (p=0.01) after thrombolysis. There were no significant differences in sICH between patients with and without LA on MRI. In univariate analysis for the occurrence of poor outcome at 90 days after thrombolysis, the size of ischemic lesion on diffusion weighted images (DWI), [odds ratio (OR), 1.03; 95% confidence interval (95% CI), 1.01-1.04; p<0.01], recanalization (OR, 0.03; 95% CI, 0.01-0.10; p<0.01), sICH (OR, 12.2; 95% CI, 1.54-95.8), neurologic severity (OR, 1.17; 95% CI, 1.09-1.25; p<0.01), blood glucose level (OR, 1.01; 95% CI, 1.00-1.02; p=0.03), and the presence of LA on MRI (OR, 2.01; 95% CI, 1.04-3.01; p=0.04) were statistically significant. In multivariate analysis, neurologic severity (OR, 1.14; 95% CI, 1.04-1.24; p<0.01), recanalization (OR, 0.03; 95% CI, 0.01-0.11; p<0.01), lesion size on DWI (OR, 1.02; 95% CI, 1.01-1.03; p=0.02), serum glucose level (OR, 1.01; 95% CI; 1.01-1.02; p=0.03), and the presence of LA on MRI (OR, 3.2; 95% CI, 1.22-8.48; p<0.01) showed statistically significant differences. These trends persisted up to 1 yr after thrombolysis. Conclusion : In this study, we demonstrated that the presence of LA on MRI might be related to poor outcome after use of intravenous tissue plasminogen activator in AIS.

• 터널과지하공간
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• 제23권6호
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• pp.480-492
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• 2013

비화산지대에서도 적용 가능한 인공저류층 생성방식의 지열발전기술의 등장으로 막대한 비용이 소요되는 대심도 시추공사를 효율적이고 경제적으로 수행하기 위한 연구개발의 필요성이 증대되고 있다. 그러나 시추공사는 수행과정에서 수많은 불확실한 사건이 발생하여 공기와 비용을 신뢰적으로 예측하기가 매우 어렵기 때문에 계획적이고 효율적으로 공사를 관리하기가 어려운 실정이다. 특히, 비트의 마모로 인해 이산적으로 발생하는 시추장비의 라운드 트립(round trip)은 심도가 깊어질수록 소요시간이 증가하여 공사 성능에 영향을 많이 끼치는 요소로서 발생시점과 깊이를 사전에 평가하여 최적화할 수 있는 기술이 필요하다. 본 연구에서는 비트의 마모상태를 총 8단계로 구분하여 마모단계별 라운드 트립이 발생되는 깊이와 시점을 분석할 수 있는 예측 알고리즘(TOSA)을 개발하였다. 시뮬레이션을 위한 단위구간을 분할할 수 있는 방법론을 제시하였으며, 구간별 시추속도 및 비트의 마모도 예측을 위한 방법으로 Bourgoyne and Young의 모델을 활용하였다. 마지막으로 사용자 편의성을 고려하여 개발된 알고리즘을 시스템화 하였다.