• Earthquakes and Structures
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• 제17권3호
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• pp.245-256
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• 2019

An experimental study was conducted to evaluate the dynamic behavior of a free-standing frame equipped with a movable base system using cast iron and mortar as the bearing materials. The preliminary friction test indicated that a graphite layer developed on the interface and exhibited stable friction behavior. The friction coefficient ranged from 0.33 to 0.36 when the applied normal compression stress ranged from 2.6 to 5.2 MPa. The effect of the variation of normal compression stress would be small. Shaking table tests on the free-standing frame showed that rock, slide, and rock-slide responses occurred. The cumulative slide distance reached 381 mm under JMA Kobe wave excitation; however, only a few cyclic slides occurred at the same locations along the moving track. Most surfaces sustained single slides. Similar results can be observed in other shaking conditions. The insufficient cyclic sliding and significant rocking resulted in a few graphite layers on the mortar surfaces. Friction coefficients were generally similar to those obtained in the preliminary friction tests; however, the values fluctuated when the rocking became significant. The collisions due to rocking caused strong horizontal acceleration responses and resulted in high friction coefficient. In addition, the strong horizontal acceleration responses caused by the collisions made the freestanding specimen unable to reduce the input horizontal acceleration notably, even when slippage occurred. Compared with the counterpart fixed-base specimen, the specimen equipped with the iron-mortar base could reduce the horizontal acceleration amplification response and the structural deformation, whereas the vertical acceleration response was doubled due to collisions from rocking.

• 대한예방한의학회지
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• 제17권3호
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• pp.143-153
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• 2013

Objective : This study was done to define the treatment protocol of Traditional Korean Medicine for persistent allergic rhinitis, which might be necessary for conducting PRCT study. Methods : Data were collected by questionnaire from Korean Medicine doctors participated in the Conference of The Korean Oriental Medical Ophthalmology & Otolaryngology & Dermatology Society in October 2012. We investigated their treatment procedures for persistent allergic rhinitis in ordinary clinical settings. Their treatment patterns including annual treatment period, frequencies and treatment times were also investigated. Finally, we combined the national insurance covered or out-of-pocket treatments as treatment packages according to the response rates of each contents, and displayed them as treatment protocols for PRCT study. Results : 50 Korean medicine doctors described the informed consent and questionnaire. Response rates of each treatment procedure were listed in Table 2 to Table 5. Treatment periods, frequencies and treatment time of each visit were listed in Table 6. Finally, treatment packages which would be defined for PRCT were listed in Table 7 as treatment package 1(response rates were over 50%), package 2(response rates were over 25%), package 3(response rates were over10%). Conclusion : These results provide the rational background and preliminary sources of defining treatment packages for developing PRCT protocols.

• The Korean Journal of Pain
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• 제23권4호
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• pp.254-257
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• 2010

Background: Epidural steroid injection is an established treatment modality for intervertebral disc prolapse to radiculopathy. In cases where two levels of radiculopathy are present, two separate injections are warranted. Herein, we present our experience of management of such cases with a single epidural injection of local anaesthetic, tramadol and methylprednisolone, and table tilt for management of both radiculopathies. Methods: 50 patients of either sex aged between 35-65 years presenting with features of cervical and lumbar radiculopathic pain were included and were subjected to single lumbar epidural injection of local anaesthetic, tramadol and methylprednisolone, in the lateral position. The table was then tilted in the trendelberg position with a tilt of 25 degrees, and patients were maintained for 10 minuted before being turned supine. All patients were administered 3 such injections with an interval of 2 weeks between subsequent injections, and pain relief was assessed with a visual analogue scale. Immediate complications after the block were assessed. Results: Immediate and post procedural complications observed were nausea and vomiting (20%), painful injection site (4%), hypotension (10%) and high block (4%). Pain relief was assessed after the three injections by three grades: 37 (74%) had complete resolution of symptoms; 18% had partial relief and 8% did not benefit from the procedure. Conclusions: This technique may be used as an alternative technique for pain relief in patients with unilateral cervical and lumbar radiculopathies.

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1246-1254
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• 2018

The importance of performing Level 3 probabilistic safety assessments (PSA) along with a general interest in assessing multi-unit risk has been sharply increasing after the Fukushima Daiichi nuclear power plant (NPP) accident. However, relatively few studies on multi-unit Level 3 PSA have been performed to date, reflecting limited scenarios of multi-unit accidents with higher priority. The major difficulty to carry out a multi-unit Level 3 PSA lies in the exponentially increasing number of multi-unit accident combinations, as different source terms can be released from each NPP unit; indeed, building consequence models for the astronomical number of accident scenarios is simply impractical. In this study, a new approach has been developed that employs the look-up table method to cover every multi-unit accident scenario. Consequence results for each scenario can be found on the table, established with a practical amount of effort, and can be matched to the frequency of the scenario. Preliminary application to a six-unit NPP site was carried out, where it was found that the difference between full-coverage and cut-off cases could be considerably high and therefore influence the total risk. Additional studies should be performed to fine tune the details and overcome the limitations of the approach.

• 감성과학
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• 제9권spc3호
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• pp.187-196
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• 2006

본 연구는 실용테이블 데커레이션의 수준별 요소에 일정한 규칙의 색채변환을 주어 관찰자(응답자) 선호의 색채 테이블과 이미지 형용사, 심미성의 각 영향 요소간의 관계성 고찰로 이는 선행 연구인 '식음 테이블 데커레이션의 관찰자 선호도에 대한 조사 분석'의 검증연구이다. 연구결과로 색채 이미지와 선호도는 '고급스러운, 먹고싶은'의 이미지로, 중 저의 어두운 톤인 브라운 색채와 '따뜻한, 화사한' 이미지의 주황색 톤이 선호되었다. 선호도와 심미성 영향 요소와의 관계 평가에서는 일반인들은 '통일성, 게슈탈트'의 영향요소를 중요하게 인식하였고, 비전문가들은 '독특성'이 부각되었다. 본 연구는 자극물 선정에서 색채 변환에 의존함에 따라 T P O에 적합한 분위기 연출의 미흡 부적합 등 현실성의 문제점과 설문 응답이 이루어진 시기, 즉 계절, 세대 간 변수, 자극물 선정 등의 문제점이 제기되나, 실용 테이블 데커레이션에의 선호 디자인에 대한 프로세스를 제안함으로써 정성적 연출뿐만 아니라 정량적인 데이터를 이용한 새로운 디자인 방향을 제시하였다는데 의의가 있다.

• KIEAE Journal
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• 제8권1호
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• pp.53-60
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• 2008

The daylighting affects on the human biological cycles and physiological alterations. Daylighting is also an important element in visual comfort and it sometimes influences the quality of vision. Therefore the absence of natural light during the day brings contradictory result. To solve the problems of natural light lack and provide sufficient daylight in interior spaces, it might be necessary to apply some daylighting systems. One of these systems, light pipe system, which is simple, cheep and easily constructed, is very useful to apply for small buildings. The light pipe is simple means of directing daylighting (diffuse and direct lighting)into interior space. In order to application of light pipe system in Korea, it is necessary to optical data of light pipe system. This study aims to evaluate preliminary experiment of the daylighting environment of light pipe system. Light pipe system, that aspect ratio is 1:2(diameter and length), was installed in a windowless mock-up with $27m^2$. The mock-up model was constructed as a prototype of Korean office surface. Illuminance was measured with a Topcon IM-5 Luxmeter to evaluate the distribution of the illuminance on a floor. The indoor and outdoor illuminance and the internal/external illuminance ratio are compared to discuss with in the graphs. Luminance was measured with Radiant imaging Promertric 1400 that is digital photometer to evaluate the distribution of luminance on interior surface. The contrast of luminance is discussed with table and graphs.

• Journal of Magnetics
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• 제22권2호
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• pp.238-243
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• 2017

In this research, we report the preliminary results of an insertional type parallel transmission (pTx) array that has 7-elements that are placed in the space above a patient table as a transmit (Tx) coil to give an RF transmission ($B_1{^+}$) field for the body object of a 3 Tesla (T) MRI system. In previous research, we have tried to compare the performances of different coil elements and array geometries for a pTx body image. Based on these results, we attempt to obtain a human image with the proposed pTx array. Through the simulation and experimental results, we introduce a possible structure of multi-channel Tx array and verify the utility of a multi-channel Tx body image using $B_1{^+}$ shimming. The insertional pTx array, combined with a receiver (Rx) array coil, provides an enhanced $B_1{^+}$ field homogeneity in a large ROI image as a result of $B_1{^+}$ shimming applied over the full body size object. Through this research, we hope to determine the usefulness of the proposed insertional type RF coil combination for 3 T body imaging.

• 보존과학연구
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• 통권35호
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• pp.45-55
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• 2014

태안 마도1호선에서 출수된 대나무 소반은 해양에 매장되어 있는 동안 열화되어 매우 취약한 상태였다. 따라서 치수안정화처리를 위해 약품 4종(Sucrose, Dammar gum, Cetyl alcohol, Polyethylene glycol 4000)을 사용하여 예비실험을 진행했다. 실험 결과 수용성 PEG 4000 함침 후 진공동결건조법을 적용한 시료가 형태를 잘 유지하고 처리 후 색상이 밝게 표현되어 수침대나무를 보존처리하는데 적합한 방법으로 평가되었다. 대나무 소반 2점 중 1점은 수용성 PEG 4000을 10%에서 40%까지 함침처리 한 후 진공동결건조하였다. 다른 한 점은 수용성 PEG 4000을 10%에서 70%까지 함침처리하였다. 그 후 대나무 소반의 편을 모두 해체한 후 각각의 부재를 폴리카보네이트판으로 진공동결건조하였다. 또한 형태유지 및 강도부여를 위해 아크릴을 사용하여 유물 형태에 맞추어 틀을 제작한 후 그 위에 소반을 복원함으로써 원형을 찾고 전시 및 보관이 용이하도록 하였다.

• 조형예술학연구
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• 제2권
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• pp.239-293
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• 2000

The paper aims to study how to describe the rigorous position on which semantic elements are laid, within the visual space. This purpose is, first of all, for the construction of visual syntactical semantics of the visual space. For this aim, the preliminary research begins with some definitions on : 1) visual space, visual design, visual syntactical semantic meaning, 2) position, sequence of position, 2-dim. sequence of position, and 3) 2-dim. numerical series of position, harmonious dynamic values. Here, The main issue is to define the position in general. To solve this problem, the researcher surveyed the positions on which the sets of pixemes are set up. The results are as follows ; 1. As far as the positions in visual space are concerned, they are the possible locations permitted in the visual patches. They are not the factual but the possible positions. 2.The position value that the sequential point has is not arithmetical but harmonious-dynamic, for it is not permitted for its own sake, but for the person, that is to say, for the viewer's visual perception. 3. The harmonious-dynamic value of positional sequence can be composed of the 2-dimensional successive numerical series which is, in turn, composed of the primordial 3 values x0, $\mu0$, y0. Here, the $\mu0$ is the harmonious mean value of x0 and y0. The x0 and y0 are, therefore, of the mutual dynamic relationship. 4. From this, the 2-dim general $\Delta-TABLE$ of the numerical series of position in visual design could be acquired through development of the primordial 3 values into the $X_i,\;Y_i$, orbit values.

• 대한조선학회논문집
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• 제29권1호
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• pp.1-13
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• 1992

본 논문은 선박의 초기설계와 중앙단면 설계용 지식베이스 시스템을 개발하고 지식공학이 선체구조 설계 분야에 매우 효율적으로 적용될 수 있음을 검토하는데 그 목적이 있다. 이를 위하여 첫째 구조설계에 적합한 지식베이스 전문가 시스템 개발용 도구(tool)인 E.1을 개발하였다. E.1은 C언어로 작성되었고 구조설계 과정을 효율적으로 뒷받침해주기 위해서 자동 반복 계산과 재추론 기능을 갖고 있다. 둘째 살물선의 초기설계시 주요치수 추정과 중앙단면 설계를 위한 지식베이스를 개발하였다. 이 지식베이스들은 통계적 경험식, 선급 규정, 경험적 지식 등을 rule, fact, table로 표현하여 구성하였다. 셋째 지식베이스의 추론을 통하여 중앙 단면 최적 설계 프로그램의 입력 자료를 생성하고 최적화 프로그램을 수행시키는 통합(hybrid) 시스템을 구축하였다. 넷째 보강판 설계용 지식베이스 시스템을 개발하기 위해 최적화 결과의 회귀분석을 이용하는 간이 설계법을 적용해 보았다. 이 시스템을 사용하여 살물선과 보강판의 설계과정을 보이고 그 결과를 검토해 보았다. 앞으로 E.I와 성능 개선과 더 우수한 지식베이스가 축적됨에 따라서 선체 구조설계에 사용되는 기존의 CAD 시스템의 성능이 크게 보완될 것으로 기대된다.