• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.05a
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• pp.14-14
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• 2003

Silicon carbide (SiC)는 높은 power 영역과 높은 온도영역에서도 작동 가능한 우수한 반도체 물질이다. 또한 우수한 열적 화학적, 안정성을 가지고 있어 가흑한 조건에서의 소자로써도 사용 가능하다. 현재 SiC 적용분야로는 우수한 전기적, 기계적 성질을 이용한 미세소자(MEMS)와 GaN 와 거의 유사한 격자상수를 가지는 것을 이용한 GaN epitaxial 성장의 기판으로도 사용되어진다. 그러나 SiC 는 기존의 습식식각 용매에 대해 화학적 안정성을 가지고 있기 때문에 전자소자의 제작에 있어서 플라즈마를 이용한 건식식각의 중요성이 대두되어지고 있다. 소자제작에 있어 이러한 건식식각시 식각 단면의 제어, 이온에 의한 낮은 손상 정도, 매끄러운 식각 표면, 그리고 고속의 식각 속도둥이 요구되어진다. 본 실험에서는 식각 속도의 증가와 수직한 식각 단면둥을 획득하기 위하여 SF6 플라즈마에서 Source power, dc bias voltage, 그리고 외부에서 인가되는 자속의 세기를 변화시쳐가며 식각 속도, 식각 마스크와의 식각 션택비, 식각 단면둥과 같은 SiC 의 식각 특성을 관찰하였다. 식각 후 식각 단면은 주사전자 현미경(SEM)을 통해 관찰하였다. 본 실험에서의 가장 높은 식각 속도는 분당 1850n 로써 이때의 공정조건은 1400W 의 inductive power, -600V 의 dc bias voltage, 20G 의 외부자속 세기이었다. 또한, 높은 inductive power 조건과 낮은 dc bias voltage 조건에서 Cu는 $SF_6$ 플라즈마 내에서 식각부산물의 증착으로 인해 SiC 와 무한대의 식각선택비를 보였다. 이러한 Cu 마스크를 사용한 SiC 의 식각에서는 식각 후 수직한 식각 단변을 관찰할 수 있었다. 것올 알 수 있다. 따라서, 기존의 pve 보다 세라믹 기판의 경우가 수분 흡수율이 높아 더 오랫동안 전류를 흐르게 하여 방식성이 개선된 것으로 판단된다.을 통해 경도가 증가한 시편의 경우 석출상의 크기가 5nm 이하로 매우 작고 대체로 기지와 연속적인 계면을 형성하나, 열처리가 진행될수록 석 출상의 크기가 커지고 임계크기 이상에 이르면 연속적인 계면은 거의 발견되지 않고, 대부 분 불연속적이고 확연한 계면을 형성함을 관찰 할 수 있었다. 알루미나(${\alpha}-Al_2O_3$) 기판 위에 증착한 $(Ti_{1-x}AI_{x})N$ 피막은 마찬가지로 (200) 우선 방위를 나타내었으나, 그 입자의 크기가 수십 nm로 고속도강위에 증착한 피막에 비해 상당히 크게 형성되었다. 또한 열처리 후에 AIN의 석출이 진행됨에도 불구하고 경도 증가는 나타나지 않고, 열처리가 진행됨에 따라 경도가 감소하는 양상만을 나타내었다. 결국 $(Ti_{1-x}AI_{x})N$ 피막이 열처리 전후에 보아는 기계적 특성의 변화 양상은 열역학적으로 안정한 Wurzite-AlN의 석출에 따른 것으로 AlN 석출상의 크기에 의존하며, 또한 이러한 영향은 $(Ti_{1-x}AI_{x})N$ 피막에 존재하는 AI의 함량이 높고, 초기에 증착된 막의 업자 크기가 작을 수록 클 것으로 여겨진다. 그리고 환경의 의미의 차이에 따라 경관의 미학적 평가가 달라진 것으로 나타났다.corner$적 의도에 의한 경관구성의 일면을 확인할수 있지만 엄밀히 생각하여 보면 이러한 예의 경우도 최락의 총체적인 외형은 마찬가지로 $\ulcorner$순응$\lrcorner$의 범위를 벗어나지 않는다. 그렇기 때문에

• Proceedings of the KOR-BRONCHOESO Conference
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• 1976.06a
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• pp.85.3-86
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• 1976

Sudden deafness requires immediate investigation and treat if there is to be any prospect of salvaging the hearing. It present an otological emergency and a diagnostic challenge. Sn Sudden sensorineural deafness can be caused by a wide variety of pathologies. A battery of tests and investigations must be performed forthwith if treatment is to be started without further delay. The concept that nothing can be done for the patient with sensori-neural deafness must be abandoned. Some pathologies causing sudden deafness are not amenable to therapy or can show only partial reversibility. But there are several causes, showing little or no spontaneous recovery, which do responed to appropriate treatment. It is important to identify them and concentrate on their management. The age and sex ratios and the unilaterral or bilateral nature of the lesion are related to the etiology and depend upon which type of case is included in the series. Though individually rare, collecting for about 2.5 per cent of new otoloical patients. Some 70 per cent of cases are unilateral. Viral, bacterial and treponemal infections accounted for about 30 per cent of the cases. Some 16 per cent were due to vascular lesions of the cochlea. In almost 22 per cent there was no obvious cause (idiopathic), they occurred in young adult and were either sensory or neural. About 12 per cent were traumatic and 9 per cent were ototoxic in origin. The remaining 11 per cent were due to a group of rarities. The two vital factors are the site of the lesion and the duration of the hearing loss. The earlier these are diagnosed and treated the better the response. The etiology, pathology and treatment are reviewed.

• Mood & Emotion
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• v.16 no.3
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• pp.134-139
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• 2018

Objectives : Treatment for bipolar disorder is often complicated by various clinical situations. We undertook a survey of expert opinions to facilitate clinical decisions in special situations such as weight gain, metabolic syndrome, hyperprolactinemia, genetic counseling, and treatment adherence. Methods : A written survey that asked treatment strategies related to safety and tolerability, was prepared focused on weight gain, antipsychotic related hyperprolactinemia, lamotrigine related skin rash, treatment non-adherence and genetic counseling. Sixty-one experts of the review committee completed the survey. Results : In the case of weight gain related to medications, experts preferred exercise and education for diet-control. First chosen medications were lamotrigine, aripiprazole and ziprasidone. Recommendations based on expert survey results for treatment of bipolar patients in other special situations are outlined. Conclusion : With limitation of expert opinions, authors hope that results of this study provide valuable information to make clinical decisions about treatment of bipolar disorder in complicated situations.

• The Journal of Korean Philosophical History
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• no.59
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• pp.155-190
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• 2018

The paper has focused on the 20 Iching-hexagrams from the eleventh t'ai[ ] to the final one of the Upper Book li[離] to examine the principles of learning and education involved in Xugua zhuan[序卦傳], the Ordinal Sequence of the Hexagrams as one among Ten Wings in I Ching. Some implications involved in this part of the Book of Change provides us with numerous teachings and educational principles. I try to concisely note the three teachings of the major argument as shown in the paper. Firstly, we should take the process of learning as the circular system of thought[環 相型], not as the linear system assuming the final destination like the Final Cause in the Aristotelian teleology. In the same token, the process of learning should be regarded as 'initiation', which has been initially adopted to justify the concept of education by R. S. Peters. As a circular system, there are two kinds of initiation. The one sense is 'crossing the threshold of illiteracy' seen as 'small initiation', which apprehends the points of argument in the previous paper, namely, on hexagrams from ch'ien[乾] to t'ai[泰]. The other sense is 'getting on the inside of the worthwhile activities', seen as 'Grand Initiation', which apprehend the present points of argument. Secondly, as shown in the paper, the Book enables us to recognize the process of learning as 'Seeing What Is There'. This requires us the Principles of Mean and Perfection, which are to be taken differently from the Western ones. For this a learner should always hold the endless self-reflection and attitude to re-examine the original intention of one's own, whilst he is involved in the task of learning. Finally, we should take the Principles of Change seriously, such as extremity-reversibility[物極必反] and the sense of conformity, in order that we can establish the proper educational principles to tackle the social domains of learning as well as the personal ones.

• Journal of the Korean Geosynthetics Society
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• v.22 no.1
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• pp.53-66
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• 2023

In this study, the results of the elasto-plastic beam analysis, finite element analysis and optimization design of the steel pipe sheet pile applied as an earth retaining wall under the deep excavation were presented. Through this study, it was found that the high-strength and sea resistant steel pipe has high allowable stress, excellent structural properties, favorable corrosion, and high utilization as an earth retaining wall, and the C-Y type joint has significantly improved the tensile strength and stiffness compared to the traditional P-P type. In addition, it was investigated that even if the leak or defect of the wall occurs during construction, it has the advantage of being able to be repaired reliably through welding and overlapping. In the case of steel pipe wall, they were evaluated as the best in views of the deep excavation due to the large allowable bending stress and deformation flexibility for the same horizontal displacement than CIP or slurry wall. Elasto-plastic and finite element analysis were conducted in consideration of ground excavation under large-scale earth pressure (uneven pressure), and the results were compared with each other. Quantitative maximum value were found to be similar between the two methods for each item, such as excavation behavior, wall displacement, or member force, and both analysis method were found to be applicable in design for steel pipe sheet pile wall. Finally, it was found that economical design was possible when determining the thinnest filling method with concrete rather than the thickest hollow shape in the same diameter, and the depth (the embedded length through normality evaluation) without rapidly change in displacement and member force.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.5-9
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• 2004

In this paper, we studied the OCT(Optical Coherence Tomography) system which it has been extensively studied because of having some advantages such as high resolution cross-sectional images, low cost, and small size configuration. A basic principle of OCT system is Michelson interferometer. The characteristics of light source determine the resolution and the transmission depth. As a results, the light source have a commercial SLD with a central wavelength of 1,285 nm and FWHM(Full Width at Half Maximum) of 35.3 nm. The optical delay line part is necessary to equal of the optical path length with scattered light or reflected light from sample. In order to equal the optical path length, the stage which is attached to reference mirror is moved linearly by step motor And the interferometer is configured with the Michelson interferometer using single mod fiber, the scanner can be focused of the sample by using the reference arm. Also, the 2-dimensional cross-sectional images were measured with scanning the transverse direction of the sample by using step motor. After detecting the internal signal of lateral direction at a paint of sample, scanner is moved to obtain the cross-sectional image of 2-demensional by using step motor. Photodiode has been used which has high detection sensitivity, excellent noise characteristic, and dynamic range from 800 nm to 1,700 nm. It is detected mixed small signal between noise and interference signal with high frequency After filtering and amplifying this signal, only envelope curve of interference signal is detected. And then, cross-sectional image is shown through converting this signal into digitalized signal using A／D converter. The resolution of the OCT system is about 30$\mu\textrm{m}$ which corresponds to the theoretical resolution. Also, the cross-sectional image of ping-pong ball is measured. The OCT system is configured with Michelson interferometer which has a low contrast because of reducing the power of feedback interference light. Such a problem is overcomed by using the improved inteferometer. Also, in order to obtain the cross-sectional image within a short time, it is necessary to reduce the measurement time for improving the optical delay line.

• Tuberculosis and Respiratory Diseases
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• v.50 no.3
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• pp.293-299
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• 2001

Background : Sustained-release theophylline, which is generally prescribed as a twice-daily equal-dose regimen, is one of the more common asthma treatments. The development of a sustained-release drug delivery technology that enables improved control of the theophylline blood levels represents a significant advancement in both the efficacy and safety of dosing. Method : A crossover study was conducted with 25 adult chronic asthmatic patients requiring daily bronchodilator therapy. The study group included thirteen males and twelve females with ages ranging from 19 to 71 years. The overall approach was to place the patients first on the twice-daily preparation($Etheophyl^{(R)}$) for 28 days at 8 AM and 8 PM, and measure the pulmonary function and theophylline level on the 28th day. The patients were subsequently switched to the once-daily preparation($Uniphyl^{(R)}$) in the same daily dose at 8 PM on the 29th day and the same parameters were measured on the 56th day. Results : The mean serum levels of theophylline were $8.18{\pm}1.66\;{\mu}g/ml$ in the $Etheophyl^{(R)}$-treated period and $8.00{\pm}1.75\;{\mu}g/ml$ in the $Uniphyl^{(R)}$-treated period. ln addition, the $FEV_1$ showed $71.40{\pm}7.48$ percent in the $Etheophyl^{(R)}$-treated and $69.18{\pm}9.00$ percent in the $Uniphyl^{(R)}$-treated period. Thus there were no significant differences between the once-daily and twice-daily preparation. Conclusion : The results indicated little clinical differences between the two medications. The two drugs are equally effective in controlling asthma over the four weeks of treatment.

• Journal of Hospice and Palliative Care
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• v.6 no.1
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• pp.11-21
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• 2003

This paper addresses the minor differences in the description of pain in Korean language in order to develop a standarized cancer pain aneument tool for Korean adults, Korean Cancer Pain Assessement Tool. The subtle differences in the meaning of expressions used cannot be translated into English and therefore we omiltted the English abstract.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.811-817
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• 2009

Purpose : Inhaled corticosteroids (ICS) are used as first-line agents for the treatment of persistent asthma; however, their use is accompanied by apprehension of potential systemic adverse effects. This study aimed to assess the effects of ICS on bone mineral density (BMD) and bone metabolism in children with asthma. Methods : From February 2008 to September 2008, 26 asthmatic children treated with ICS (ICS group), 15 asthmatic children treated with leukotriene receptor antagonist (LTRA) (LTRA group), and 30 healthy children (Control group) were selected from the Korea University Anam Hospital. BMD and serum bone-specific alkaline phosphatase (BALP) levels were measured. The asthmatic children underwent spirometry and methacholine bronchial challenge test. Results : There were no significant differences in BMD in the lumbar spine (P=0.254) and proximal femur (P=0.297) among the 3 groups. The serum BALP levels were significantly higher in both the ICS (P=0.017) and LTRA (P=0.025) groups than in the Control group. None of the parameters pertaining to ICS use, such as the mean daily dose during the last 6 months, the total cumulative dose, duration of use, and age of commencement of use, showed significant correlations with BMD (P>0.05 for all parameters). Conclusions : We demonstrated that a low dose of ICS does not exert any significant adverse effect on bone metabolism in asthmatic children. These findings support the current recommendations with regard to the use of ICS for asthmatic children.

• Journal of agricultural medicine and community health
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• v.26 no.2
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• pp.133-146
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• 2001

The purpose of this study was to investigate the treatment status and its related factors of the newly detected rural hypertensives through community health promotion program. A questionnaire survey and blood pressure measurement were performed to 6,977 residents of a rural area, and 282 hypertensives detected by blood pressure measurement were selected as subjects of the study. The study employed the health belief model as a hypothetical model. The major results of this study were as follows: The proportion of person experienced treatment among hypertensives was 12.0%. Treatment experience rate was significantly related with age and educational level(p<0.01). That is, if they were older, lower educational level, the treatment experience rate was higher. The major reasons of no treatment were 'they had not hypertensive symptoms ' (45.6%), 'their blood pressure was not high so much that they received treatment ' (43.2%). The chief facilities for treatment were public health institutions(57.9%) such as health center and health subcenter, and hospital/ clinics(29.8%). The treatment experience rate was higher when they had higher perceived severity for hypertension, lower perceived barrier to treatment, although statistically not significant. Treatment experience rate was significantly related with cues to action and health education experience(p<0.05). That is, if they had hypertension related symptoms such as headache previously, patients suffered from hypertension complication and health education experience for hypertension, the treatment experience rate was higher. In multiple logistic regression analysis for treatment experience, having a cerebrovascular patient in their acquaintance and the experience of health education for hypertension were significant variables. On consideration of above findings, it would to be essential to provide knowledge about hypertension and its treatment, and severity of hypertension complications through health education.