• 한국지능시스템학회논문지
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• 제25권1호
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• pp.1-6
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• 2015

본 논문에서는 한 바퀴 이동로봇의 균형제어를 위해 퍼지방법을 사용하였다. PD제어를 사용하여 균형을 유지하는 한 바퀴 로봇은 시간이 지남에 따라 플라이휠이 한 방향으로 기울어지게 되고 결국에는 균형이 무너지는 현상이 발생한다. 선행연구에서는 이를 해결하기 위해 게인 스케줄링 방법을 사용하였다. 본 논문에서는 퍼지방법을 사용하여 균형 각도를 보상하므로 균형 제어 성능을 높이고자 하였다. 퍼지제어를 통해 desired offset의 각도를 보상하므로 김벌이 한쪽으로 흘러 넘어지는 현상을 보완하였다. 한 바퀴 구동 이동로봇의 균형제어 실험을 통하여 제안하는 제어방식의 성능을 검증하였다.

• 융합보안논문지
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• 제3권2호
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• pp.71-83
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• 2003

정보통신 기술의 발달은 인류에게 고도의 합리화를 추구하고, 시간 공간을 초월하여 다양한 혜택을 누리게 만들었다. 정보가 자원인 사회구조에서 정보통신 기술의 발달은 정보화 혁명을 일으켰고, 인간의 발전에 크게 기여하고 있다. 정보통신 기술의 발달로 인하여 인류의 발전에 기여한 반면 동시에 인류사회를 위협하는 역기능을 수반하고 있다. 지식정보사회 발전의 관건은 정보화 사회의 순기능을 발전시키고 역기능을 적절히 규제 할 수 있는 정보보호 기술의 발전과 제도적으로 정보보호를 효율적으로 할 수 있는 방안을 찾는 것이다. 지식정보사회의 발전을 가로막고 있는 정보사회의 역기능에 대한 사례 및 정보보호관련 법률의 구조 및 개념에 대한 문제와 현 사회에 부적절한 법규제도의 개선방안에 대하여 논하였다.

• 대한기계학회논문집B
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• 제22권5호
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• pp.685-697
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• 1998

Series of recent k-.epsilon. model modification have been carried out with the aid of DNS data to include the effect of near wall. Though these methods opened new way of turbulence modelings, newly developed turbulence models of its kind had yet shortcomings in prediction for the turbulent flows with various Reynolds numbers and various geometric conditions. As a remedy for these shortcomings, a new k-.epsilon. model proposed here by improving the dissipation rate equation and the damping function for eddy viscosity model. The new dissipation rate equation was modeled based on the energy spectrum and magnitude analysis. The damping function for eddy viscosity was also formulated on the ground of distribution of dissipation rate length scales near a wall and the DNS data. The new k-.epsilon. model was applied to the fully developed turbulent flows in a channel and a pipe with a wide range of Reynolds numbers. Prediction results showed that the present model represents properly the turbulence properties in all turbulent regions over a wide range of Reynolds numbers.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 춘계학술대회 논문집
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• pp.404-409
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• 2004

To maximize the productivity in machining molds and dies, machine tools should operate at high speeds. During the high speed operation of moving frames or spindles, vibration problems are apt to occur if the machine tool structures are made of conventional steel materials with inferior damping characteristics. However, self-excited vibration or chatter is bound to occur during high speed machining when cutting speed exceeds the stability limit of machine tool. Chatter is undesirable because of its adverse effect on surface finish, machining accuracy, and tool life. Furthermore, chatter is a major cause of reducing production rate because, if no remedy can be found, metal removal rates have to be lowered until vibration-free performances is obtained. Also, the resonant vibration of machine tools frequently occurs when operating frequency approaches one of their natural frequencies because machine tools have several natural frequencies due to their many continuous structural elements. However, these vibration problems are closely related to damping characteristics of machine tool structures. The polymer concrete has high potential for machine tool bed due to its good damping characteristics with moderate stiffness. This paper presents the use of polymer concrete and sandwich structures to overcome vibration problems. Also, co-cure bonding method for functional part mounting was exhibited experimentally, by which manufacturing time and cost for polymer concrete bed will be remarkably reduced.

• 센서학회지
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• 제16권1호
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• pp.44-51
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• 2007

A hybridized simulator for generating blood pressure waveform is proposed to study the remedy and/or evaluation of the conventional sphygmomanometer utilizing the oscillometric method which is widely applied. The blood pressure of a flowing fluid was controlled for the blood vessel's condition caused by a rhythmical and periodical contraction/relaxation because of the special excitatory and conductive system of the heart. In this study, a hybridized controller composed of the PI feedback controller and the feedforward controller. The inverse dynamics function is proposed to operating the control valve while the pressure is applied in an oil pressure tank. The proposed hybrid simulator reproducing the blood pressure waveform in an artificial blood vessel has kept the control performance consistent over all range. Based on these results, the proposed simulators could be applied to the development and compensation of the non invasive sphygmomanometer type as well as to study the characteristics of the blood pressure and blood vessel.

• 대한기계학회논문집A
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• 제26권6호
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• pp.1077-1084
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• 2002

Optimum tool design is carried out fur a multi-stage rectangular cup deep-drawing and ironing process with the large aspect ratio. Finite element simulation is carried out to investigate deformation mechanisms with the initial design made by an expert. The analysis considers the deep drawing process with ironing for the thickness control in the cup wall. The analysis reveals that the difference of the drawing ratio within the cross section and the irregular contact condition produce non-uniform metal flow to cause wrinkling and severe extension. For remedy, the modification guideline is proposed in the design of the tool and the process. Analysis results confirm that the modified tool design not only improves the quality of a deep-drawn product but also reduces the possibility of failure. The numerical result shows fair coincidence with the experimental one. After tryouts of the tool shape, the rectangular cup has been produced in the transfer press.

• 대한약침학회지
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• 제22권4호
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• pp.204-209
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• 2019

Premenstrual syndrome (PMS) encompasses a vast array of physical and psychological symptoms. Of the herbal supplements mentioned for remedy PMS symptoms, chamomile used as an effective herbal medicine. The overall purpose of this review was to determine the efficacy of chamomile on the treatment PMS. An extensive research review using Web of Science, the Cochrane Controlled Trials Register database, PubMed, Chinese Biomedical Database (CBM), CINAHL, China National Knowledge Infrastructure (CNKI), Psych INFO, Social Science Research Network, SID, Google Scholar, Iran Doc, Magiran and Iran Medex. Eligible studies were identified from English and Persian databases, published between 1990 and 2019. Studies were screened independently by two researchers who performed the data extraction. Of Twenty-seven studies identified, Eight RCTs met our inclusion criteria. Chamomile has been used to treat PMS relief because of therapeutic properties such as anti-inflammatory effects (Chamazulene and α-Bisabolol); anti-spasmodic effects (Apigenin, Quercetin, and Luteolin, Metoxicomarin, Matrisin, and Phytoestrogens); anti-anxiety effects (Glycine, Flavonoid). The results of this review show that Chamomile is effective for the treatment of PMS. Based on these results, we believe that Chamomile can be used as good herbal medicine to treat in women with PMS.

• 대한약침학회지
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• 제9권3호통권21호
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• pp.155-160
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• 2006

Objective : The purpose of this study is to examine if scolopendrid acuacupucture may be effective to the lateral epicondylitis. Methods : Using scolopendrid aquacupucture, we injected a small dose of it to the affected area and operated 2 pre and post treatment test; VAS(visual analogue scale), PPT(pressure pain threshold). Results : The scolopendrid aquacupucture treatment led to improvement in the pain and symptom of lateral epicondylitis by all efficacy measures. After scolopendrid aquacupucture treatment, there was improvement in VAS, PPT. Conclusion :This results suggest that scolopendrid aquacupucture is good method for treatment of lateral epicondylitis, so we suggest the possibility to use this new remedy for the lateral epicondylitis.

• 대한약침학회지
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• 제8권1호
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• pp.13-20
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• 2005

Objectives : This study is performed for the purpose of examining into the efficacy of the scolopendrid herbal acupucture which has been used among the Korean people for the Carpal tunnel syndrome. Methods : 40 carpal tunnel syndrome patients who visited Won-kwang University Hospital during the period from January 1998 to December 2004 were analysed for clinical manifestations. After we divided patients into two classes at random, we treated them with scolopendrid herbal acupucture or not. Treatment efficiency was monitored through VAS(Visual Analog Scale) and clinical symptom. Conclusion : We brought to the conclusion that the scolopendrid herbal acupucture has possibility to be efficient to cure the carpal tunnel syndrome patients. So we suggest the possibility to use this new remedy for the carpal tunnel syndrome.

• 동의생리병리학회지
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• 제18권5호
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• pp.1382-1386
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• 2004

This study was performed for the investigation of vasodilatory efficacy and its underlying mechanisms of Samhwangsasim-tang(SST), herbal remedy. SST relaxed vascular strips precontracted with phenylephrine or KCI(51 mM), but the magnitude of relaxation was greater in phenylephrine(PE) induced contraction. The relaxation effects of SST was endothelium-independent. L-NAME, iNOS inhibitor, and methyl en blue(MB), cGMP inhibitor, did not attenuate the relaxation responses of SST. In the absence of extracellular Ca2+, pre-incubation of the aortic rings with SST significantly reduced the contraction by PE, suggesting that the relaxant action of the SST includes inhibition of Ca/sup 2+/ influx and release of Ca/sup 2+/ from intracellular stores (SR). In addition, the cell death was induced by SST in human aortic smooth muscle cells but not that of human umbilical vein endothelial cells. We conclude that in rat thoracic aorta, SST may induce in part vasodilation through inhibition of Ca/sup 2+/ influx and release of Ca/sup 2+/ from intracellular stores.