• 지질공학
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• 제26권2호
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• pp.169-175
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• 2016

Estimations of regional stress are demonstrated in this paper. Firstly, regional stress is defined and the characteristics of regional stress are then discussed based on the local stresses measured by the Compact Conical-ended Borehole Overcoring (CCBO) technique and the results from the earthquake focal mechanism. Secondly, the regional stresses are estimated by a back analysis of three-dimensional finite element models, using the local stresses measured by the CCBO and hydraulic fracturing.

• 디지털융복합연구
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• 제1권1호
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• pp.213-234
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• 2003

"Trust" becomes a focal issue in e-business. Unlike traditional business environment, virtual situation requires new trust-ensuring mechanism other than face-to-face meetings and other related means of confirmation. Many countries are trying to foster trust services industry in order to increase e-business transactions and activities. This paper compares and contrasts these countries' policies on trust services. Conclusions of this comparative research includes: (1) trust services industry will be tightly integrated horizontally and increase their scope vertically towards trust in business sense over and beyond the mere technical level trust, (2) necessity of reciprocal trust authentication exchange is calling for an international standard in a near future, and (3) two different types of policies are under development: government-led and industry-led. Advantages and disadvantages of different approaches are presented with details of legal implications and structures of operations.

• The Korean Journal of Pain
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• 제25권2호
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• pp.75-80
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• 2012

Hypnosis is an altered state of consciousness that comprises of heightened absorption in focal attention, dissociation of peripheral awareness, and enhanced responsiveness to social cues. Hypnosis has a long tradition of effectiveness in controlling somatic symptoms, such as pain. Pain, the most common symptom in clinical practice, is a multi-dimensional experience, which includes sensory-discriminative, affective-emotional, cognitive and behavioral components. There is a growing recognition for hypnosis and related techniques in pain management. Psychological approaches to pain control, such as hypnosis, can be highly effective analgesics, but are underused in Korea. In this article, we would like to review the basic concepts of hypnosis, the mechanism, and the outcome data of the analgesic effects of hypnosis, and also, its limitations.

• The Korean Journal of Pain
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• 제24권1호
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• pp.57-60
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• 2011

Pulsed radiofrequency (PRF) treatment of nervous tissue has been proposed as a less neurodestructive technique alternative to continuous RF heat lesioning. Recently, clinical reports using PRF have shown favorable effects in the treatment of a variety of focal pain areas, even in non-nervous tissues; however, the mechanism of effect underlying this treatment to non-nervous tissue remains unclear. We report the case of a 67-year-old male who presented with pain reliving point in the posterior neck. The patient had pain in the posterior neck for 3 years. The pain subsided with pressure applied to a point in the posterior neck. There were no specific abnormal findings on laboratory testing and radiologic examinations. After PRF treatment to the pain-relieving point, he had pain relief which lasted more than 5 months.

• 비파괴검사학회지
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• 제22권6호
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• pp.637-642
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• 2002

An arc-shaped line array slit has been used for the laser generation of focused Lamb waves. The spatially expanded Nd:YAG pulse laser was illuminated through the arc-shaped line array slit on the surface of a sample plate to generate the Lamb waves of the same pattern as the slit. Then the generated Lamb waves were focused at the focal point of which distance from the slit position is dependent on the curvature of slit arc. The proposed method showed better spatial resolution than the conventional linear array slit in the detection of laser machined linear defect and drill machined circular defect on aluminum plates of 2mm thickness. Using the focused waves, we could detect the linear defect and the circular defect with the improvement of spatial resolution. The method can also be combined with the scanning mechanism to get an image just like by the scanning acoustic microscope(SAM).

• 대한금속재료학회지
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• 제50권3호
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• pp.233-236
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• 2012

ZnO nanowires were fabricated through thermal evaporation of Zn or ZnS powder using solar energy. The Zn or ZnS powder was heated and evaporated by sunlight. The sunlight was concentrated on the Zn or ZnS powder by a converging lens and then the Zn or ZnS powder was evaporated and oxidized in air. After oxidation, ZnO nanowires were fabricated in the focal point. Strong ultraviolet emission, which corresponds to the near band-edge emission, was observed from the ZnO nanowires synthesized using Zn powder as a source material. Meanwhile, green emission, related to intrinsic defects such as oxygen vacancies, prevailed for the ZnO nanowires fabricated using ZnS powder. No catalysts were used in the fabrication of the ZnO nanowires, which suggested the ZnO nanowires were grown by a vapor-solid mechanism.

• Nutrition Research and Practice
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• 제14권2호
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• pp.127-133
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• 2020

BACKGROUND/OBJECTIVES: Non-small cell lung cancer is mostly recognized among other types of lung cancer with a poor prognosis by cause of chemotherapeutic resistance and increased metastasis. Luteolin has been found to decrease cell metastasis. However, its underlying mechanisms remain unresolved. The objective of this study was to examine the effect (and its mechanism) of luteolin on the migration and invasion of human non-small cell lung cancer A549 cells. MATERIALS/METHODS: Cell viability was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Wound healing and transwell assays were evaluated to assess migration and invasion, respectively. Western blot analysis and immunofluorescence were further performed to investigate the role of luteolin and its mechanisms of action. RESULTS: Administration with up to 40 μM luteolin showed no cytotoxic activity on lung cancer A549 cells or non-cancer MRC-5 cells. Additionally, luteolin at 20-40 μM significantly suppressed A549 cells' migration, invasion, and the formation of filopodia in a concentration-dependent manner at 24 h. This is similar with western blot analysis, which revealed diminished the phosphorylated focal adhesion kinase (pFAK), phosphorylated non-receptor tyrosine kinase (pSrc), Ras-related C3 botulinum toxin substrate 1 (Rac1), cell division control protein 42 (Cdc42), and Ras homolog gene family member A (RhoA) expression levels. CONCLUSIONS: Overall, our data indicate that luteolin plays a role in controlling lung cancer cells' migration and invasion via Src/FAK and its downstream Rac1, Cdc42, and RhoA pathways. Luteolin might be considered a promising candidate for suppressing invasion and metastasis of lung cancer cells.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.392-392
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• 2011

Carbon nanotubes (CNT) emitter has widely become an attractive mechanism that draws growing interests for cold cathode field emission.$^{1,2}$ CNT yarns have demonstrated its potential as excellent field emitters.$^3$ Extensive simulations were carried out in designing a CNT yarn-based cathode assembly. The focal spot size dependence on the anode surface of the geometric parameters such as axial distance of the electrostatic focus lens from the cathode and the applied bias voltages at the cathode, grid mesh and electrostatic focus lens were studied. The detailed computer simulations using Opera 3D electromagnetic software$^4$ had revealed that a remarkable size of focal spot under a focusing lens triode type set-up design was achieved. The result of this optimization simulation would then be applied for the construction of the CNT yarn based micro-focus x-ray tube with its field emission characteristics evaluated.

• 대한한방내과학회지
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• 제24권2호
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• pp.181-189
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• 2003

The goal of this study is to investigate whether Uncariae Ramulus et Uncus can protect nerve cells against ischemic neuronal damage is caused by middle cerebral artery occlusion (MCAO) in rats' brains and to investigate whether the neuroprotective effect of Uncariae Ramulus et Uncus is concerned with IEGs(immediate early genes) expression. Uncariae Ramulus et Uncus(l00mg/kg) was administered immediately after 2 hours of MCAO and maintained for 7 days. On 7th days after 2 hours of MCAO, the brains of rats were sliced through the hippocampus. c-Fos immunohistochemistry stain and Cresyl violet stain were done for microscopic examination. Each number of viable neurons and c-Fos immunoreactive cells in CA1 was counted. The density of neurons and c-Fos immunoreactive cells were significantly decreased in MCAO-operated ischemic rats compared to that sham-operated rats. Administration of Uncariae Ramulus et Uncus group significantly elevated MCAO-induced decrease in density of neurons, and elevated MCAO-induced decrease in c-Fos immunoreactive cells. These results suggest that the neuroprotective effect of Uncariae Ramulus et Uncus against focal cerebral ischemia. Also, we hypothesized that neuroprotective mechanism of Uncariae Ramulus et Uncus is related to IEGs expression.

• 지질공학
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• 제19권4호
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• pp.509-515
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• 2009

1999년 경상북도 경주 인근에서 지역규모($M_L$) 3.0 이상의 지진이 3차례(4월 24일, 6월 2일, 9월 12일)에 걸쳐 발생하였다. 진앙의 위치를 재결정한 결과 이 지진들의 진앙 사이 거리는 반경 1 km 내에 포함된다. 파형역산을 수행하여 6월 2일 지진의 발진기구를 분석하였으며, 나머지 지진들은 P파와 S파의 초동극성 및 진폭비를 이용하여 발진기구를 분석하였다. 6월 2일 및 9월 12일 지진은 단층면해가 서로 비슷하고, 4월 24일 지진은 상기 지진들의 단층면해를 포함하나 그 분포 범위가 상대적으로 넓다. 이 지진들의 발진기구는 공통적으로 약간의 정단층 성분을 포함한 주향이동단층의 특성을 보이며, P축의 방향은 동북동-서남서 방향으로 한반도 주응력 방향에 대한 이전 연구결과와 부합한다. 진앙 사이의 거리, 지진파형의 유사성, 지진들을 공통으로 기록한 지진관측소 지진자료 극성의 동일성, 발진기구의 유사성 등을 고려했을 때, 이 지진들은 동일한 단층에서 발생했을 것으로 1999년 경상북도 경주 인근에서 지역규모($M_L$) 3.0 이상의 지진이 3차례(4월 24일, 6월 2일, 9월 12일)에 걸쳐 발생하였다. 진앙의 위치를 재결정한 결과 이 지진들의 진앙 사이 거리는 반경 1 km 내에 포함된다. 파형역산을 수행하여 6월 2일 지진의 발진기구를 분석하였으며, 나머지 지진들은 P파와 S파의 초동극성 및 진폭비를 이용하여 발진기구를 분석하였다. 6월 2일 및 9월 12일 지진은 단층면해가 서로 비슷하고, 4월 24일 지진은 상기 지진들의 단층면해를 포함하나 그 분포 범위가 상대적으로 넓다. 이 지진들의 발진기구는 공통적으로 약간의 정단층 성분을 포함한 주향이동단층의 특성을 보이며, P축의 방향은 동북동-서남서 방향으로 한반도 주응력 방향에 대한 이전 연구결과와 부합한다. 진앙 사이의 거리, 지진파형의 유사성, 지진들을 공통으로 기록한 지진관측소 지진자료 극성의 동일성, 발진기구의 유사성 등을 고려했을 때, 이 지진들은 동일한 단층에서 발생했을 것으로 추정된다. 파형역산을 수행한 결과 6월 2일 지진의 지진모멘트는 $3.9\;{\times}\;10^{14}N{\cdot}m$로 계산되었으며, 이 값은 모멘트규모 3.7에 해당한다. 스펙트럼 분석을 통해 계산된 모멘트규모는 3.8로, 파형역산에 의한 모멘트규모와 비슷하다. 평균 응력강하는 7.5 MPa로 추정되었다. 3개 지진들을 공통으로 기록한 단일 지진관측소의 스펙트럼을 서로 비교한 결과 4월 24일 및 9월 12일 지진의 모멘트규모는 각각 3.2, 3.4로 추정되었다.