• Wind and Structures
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• 제23권2호
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• pp.91-107
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• 2016

Flow-excited acoustic resonance in ducted cavities can produce high levels of acoustic pressure that may lead to severe damage. This occurs when the flow instability over the cavity mouth, which is created by the free shear layer separation at the upstream edge, is coupled with one of the acoustic modes in the accommodating enclosure. Acoustic resonance can cause high amplitude fluctuating acoustic loads in and near the cavity. Such acoustic loads could cause damage in sensitive applications such as aircraft weapon bays. Therefore, the suppression and mitigation of these resonances are very important. Much of the work done in the past focused on the fluid-dynamic oscillation mechanism or suppressing the resonance by altering the edge condition at the shear layer separation. However, the effect of the downstream edge has received much less attention. This paper considers the effect of the impingement edge geometry on the acoustic resonance excitation and Strouhal number values of the flow instabilities in a ducted shallow cavity with an aspect ratio of 1.0. Several edges, including chamfered edges with different angles and round edges with different radii, were investigated. In addition, some downstream edges that have never been studied before, such as saw-tooth edges, spanwise cylinders, higher and lower steps, and straight and delta spoilers, are investigated. The experiments are conducted in an open-loop wind tunnel that can generate flows with a Mach number up to 0.45. The study shows that when some edge geometries, such as lower steps, chamfered, round, and saw-tooth edges, are installed downstream, they demonstrate a promising reduction in the acoustic resonance. On the other hand, higher steps and straight spoilers resulted in intensifying the acoustic resonance. In addition, the effect of edge geometry on the Strouhal number is presented.

• Journal of Acupuncture Research
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• 제18권4호
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• pp.205-211
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• 2001

Objective : There was no report on traumatic pneumothorax associated with acupuncture in korea yet, although many people guess at its possibility. In order to make known that acupuncture can cause pneumothorax in reality and to prevent more acupuncture-related adverse effect cases in future, this report was made. Methods : Close observation was done on clinical symptoms & radiologic examination of acupuncture-related traumatic pneumothorax patient. Results : During acupuncture therapy on neck stiffness & shoulder pain, a acupuncture needle was inserted too deeply into upper part of thorax unintentionally, patient showed dyspnea, chest pain & discomfort, cough, sweating and mild rupture of right lung in chest radiologic findings, and recovered after 2 weeks of conservative treatment. Conclusion : In order to prevent traumatic pneumothorax during acupuncture therapy, needling into thorax sometimes requires tilted acupuncture needle inserting under consideration of needle width & length. At least 0.40mm width of needle is generally considered appropriate in needling into taut band of thoracic muscles, because too thin and long needle sometimes can be bent and inserted into wrong way, which can cause adverse effects like pneumothorax.

• 한국중재학회지:중재연구
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• 제22권1호
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• pp.111-130
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• 2012

Judgment on the validity of patents on the subject of an arbitration does not. In other words, the occurrence of patents generated by the administrative action, and such administrative action by an authorized agency may be treated as legitimate until it is canceled. However, recent Supreme Court judgment on novelty and inventive step as well as judgments about the validity of the patent also made possible by the judiciary. This progress even in the mediation of an arbitral award which is premised on the validity of patents can be seen that possible. However, if the arbitration by an arbitrator if possible a certain portion of the limit exists. In other words, the effect of arbitration between the parties is valid. This patent is valid and invalid in arbitration even if the judgment relative to the effect ceases. In addition, the arbitration award and patent invalidation trial is in progress at the same time, if you consequently will reach a different conclusion. This can cause problems of double track. In addition, by extending the critical target recognition and enforcement in other countries can cause problems. Despite these problems, now about the validity of patents that it is possible intervention is necessary to discuss again.

• 한국콘텐츠학회논문지
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• 제18권9호
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• pp.231-239
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• 2018

본 연구는 사용자를 통한 실험 및 심층면접을 통해 최근 많은 광고물량이 몰리고 있는 페이스북 광고운영에 도움이 되는 요소가 무엇이 있는지 모바일매체를 중심으로 찾아보는 탐색적 논문이다. 연구 방법은 모바일광고, 그리고 모바일광고 내 매체현황, 콘텐츠성향, 광고회피현상을 고찰한 후, 남녀 대학생 50명을 대상으로 실험자 자신의 페이스북을 30초간 체험하게 하여 사용과정에서의 물리적 행위를 관찰하고, 실험 후 토론을 기반으로 심층 분석하였다. 실험의 결과는 광고의 긍정적 요인와 부정적 요인으로 나누어 논할 수 있었다. 페이스북을 이용하는 동안 광고를 좋게 보이게 해주는 긍정적 요인으로 네이티브 광고디자인 효과, 지인 효과, 검색 효과의 영향을 받고 있음을 확인할 수 있었으며, 페이스북 사용자로 하여금 광고회피를 쉽게 해주는 광고의 부정적 요인으로 초당 평균 1.5-3회의 빠른 스크롤 행위로 광고스킵이 가능함을 발견할 수 있었다. 그러나, 부정적 행위에 해당하는 빠른 스크롤 행위는 앞서 언급한 긍정적 요소들과 더불어 페이스북은 모바일 상에서 다른 매체 대비 광고로 인한 스트레스가 높지 않다는 의견이 나왔다.

• 대한추나의학회지
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• 제3권1호
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• pp.111-123
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• 2002

Objectives : There have been many studies of the effect of Bee Venom therapy about arthritis, but no one study was reported about its whole functional mechanism to musculo-skeletal system. This study was designed to investigate the effect, Indication, and side effect of Bee Venom therapy on musculo-skeletal disease by literature review of articles. Results : The effects of Bee Venom therapy to musculo-skeletal system are divided to Anti_inflammatory effect and Anti-nociceptive effect. Anti_inflammatory effect is achieved through competitive chemotaxis, immuno-regulation, increasing of cortisol secretion by stimulating hypothalamus-pituitary gland-adrenal cortex axis. Anti-nociceptive effect is achieved by Anti-inflammatory mechanism and it works similar to anti-nociceptive effect of the acupuncture acting on central and peripheral nociceptive transduction system. The Bee Venom therapy could cause severe side effect, for example, hypersensitivity and anaphylaxis, injury to central nerve system and cardiovascular system, peripheral blood system, and renal dysfunction. Conclusions : With its Anti-inflammatory and Anti-nociceptive mechanism, Bee Venom therapy is considered that has good effects to autoimmune disease, chronic inflammation of various musculo-skeletal disease and various pain syndrome. But the clinician must be careful for its side effects.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.339-343
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• 1990

This paper describes a neural-network-based methodology for providing a potential solution in the area of process fault diagnosis. The existing neural network for fault diagnosis learn fault node by using pairs of single-symptom-single-cause only. But in real plants, the effect of a fault propagates continuously from it's origin; different sensor values reflect this. In this paper, we suggest a new method which can handle the effect of symptom propagation. The proposed method can find the exact origin of the fault of which the symptom is propagated continuously with time.

• Computers and Concrete
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• 제6권5호
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• pp.403-419
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• 2009

Short column effect is cause to failure of columns which may result in severe damages or even collapse during earthquakes. The scope of the study is mainly to reveal the effect of short column on the holistic behaviour of the buildings. The nonlinear analysis of 31 different frame buildings containing short column problem are carried out using finite element method. The finite element models were selected by 2 bays and 3 stories. Since the short columns are generally seen in the first storey of the buildings, in the study, they are only constructed in the same storey. The adverse effect of the short column on the response of buildings was shown in terms of the total load factor and displacement capacity of building. The response of buildings in terms of ground storey displacements is presented in figures and discussed. It is revealed that if the window openings are constructed along the bays, the total load capacity is decreased 85% compared with reference model in which all of bays are filled with infill walls.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.471-474
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• 1997

Recently, many studies have shown clinically the detection of proximal arterial stenosis through evaluation of a Doppler waveform alternation, the so-called pulsus tardus and parvus, that often occurs distal to the stenosis. However the cause of the tardus-parvus phenomenon remains obscure. To analyze its cause, we modeled the blood-flow circuit as simple electrical circuit. This shows that pulsus tardus-parvus effect is caused as a result of high-frequency waveform component attenuation from low-pass filtering by capacitance(complience of the poststenotic vessel wall) and resistance(stenosis). As a result, the degree of pulsus tardus-parvus increased as the complience of the poststenotic segment of vessel increased, as well as increasing stenosis.

• 한국전기전자재료학회논문지
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• 제23권2호
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• pp.93-97
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• 2010

We have studied the effect of the chemical composition of the ZnO nanorod surface on the optical characteristics. The surface was treated with H- and O-plasma at different surface temperatures. The chemical composition of the surface of the ZnO nanorod, being investigated by Auger Electron Spectroscopy(AES), was related to the Photoluminescence(PL) data reported in our previous results. The AES showed the opposite results for the $H_2$ and $O_2$ plasma treatments. The ratio of Zn to O on the surface of the ZnO nanorod increased in the case of $H_2$ plasma, while the composition rate of O increased after $O_2$ plasma treatment. The AES results seems to be correlated to the shift in PL peaks. The increase in the composition rate of Zn on the surface of ZnO nanorod is considered to cause the blue shift of the UV peak. On the contrary, the relative increase of O is considered to cause the red shift in PL peaks.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2004년도 e-Biz World Conference
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• pp.15-20
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• 2004

Positivism ▣Quantitative research ▣Descriptive, predictive, explanatory ▣Quest for university laws ▣Concerned with the empirical testability of theories (·Causal models (if it's not about cause-and-effect, it's not Science)) ▣Assumptions：(·Existence of a priori fixed relationship within phenomena ·Regular patterns of causation ·Independent from human mind(objective, factual)(omitted)