• 한국철도학회논문집
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• 제14권6호
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• pp.535-544
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• 2011

레일 표면 결함이 발생할 경우 매우 높은 충격하중이 발생하여 레일 피로 진전 또는 레일 파단에 이를 수 있고 레일이 파단될 경우 열차탈선 등 대형 사고가 발생할 수 있으므로 레일 결함부에 대한 관리기준의 정립이 매우 중요하다. 본 연구에서는 차량-궤도 동적 상호작용 해석 프로그램을 이용하여, 실제 고속철도 자갈궤도에서 결함이 발생한 43개 지점에서 측정된 레일요철을 입력값으로 하여, 요철 깊이에 따른 충격 윤중과 레일 휨응력을 산정하였다. 궤도틀림을 감안하여 윤중 및 레일 휨응력의 한계값을 설정하고, 해석결과로부터 얻은 윤중 및 레일 휨응력 최대값과 결함 깊이 및 폭과의 상관관계를 분석함으로써 레일 표면 결함부에 대한 관리기준을 제시하였다. 분석 결과, 허용할 수 있는 요철 깊이는 충격 윤중에 의하여 발생할 수 있는 레일 두부의 소성 변형을 방지하기 위하여 관리되어야 하며, 엄격한 조건을 평가할 경우 그 값은 0.2mm 정도가 적당함을 알 수 있었다.

• 사상체질의학회지
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• 제30권3호
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• pp.24-39
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• 2018

Introduction The purpose of this study was to systematically review previous studies on Sasang type-specific pathophysiological symptoms in urination and defecation. Methods Peer-reviewed articles on type-specific pathophysiological symptoms of urination and defecation published until September 2016 were extracted from domestic and international six databases. Clinical characteristics from thirteen extracted articles were categorized into three urination domains of appearance of urine, capacity of bladder and urinary discomfort, and three defecation domains of irritability of bowel movement, functional constipation and discomfort from irregularity. Results As for the urination, Tae-Eum type showed dark color with foam, however So-Eum type had frequent urination and sensitivity to dysuria but no nocturia and residual urine sense. As for the defecation, So-Yang type showed frequent urgency and constipation, however So-Eum type reported loose stool. So-Yang type showed varied level of health status depending on defecation irregularity. There were disparities with rectal tenesmus among Sasang types. Discussion Six domains of urination and defecation related type-specific pathophysiological clinical symptoms were provided in this study. This study would contribute to the standardized clinical measures of Sasang typology in the near future.

• 한국주거학회논문집
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• 제24권3호
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• pp.121-133
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• 2013

The purpose of this study is to analyze the design characteristics of external appearances of Hundertwasser's housing projects through both literature review and field study, and to understand how Hundertwasser's architecture philosophy was embodied in the design of external appearances so such projects. The subjects of the analysis are: Hundertwasser House; In the Meadow Bad Soden; The Forest Spiral Darmstadt; and The Green Citadel Magdeburg. The conclusion of the study is as follows. The fundamental architecture philosophy of Hunderwasser is the close linkage between mankind and nature. He has proven, through his four housing projects mentioned above, that it is possible to build houses without destroying and in harmony with nature. Hundertwasser had identified vitality, irregularity and diversity as being the source of beauty of nature. Using the human creativity, he had embodied such elements into his housing projects, thus suggesting an ideal housing environment whereby humanity is respected. Hundertwasser made use of organic curved line and spiral shapes that exist in nature when designing his housing projects. His creativity was articulated through vitality, diversity, and irregularity in colour schemes and a wide range of form. Indeed, he was an architect pursuing the underlying nature of both human and nature. The current living environment in Korea can be characterized as being standardized and desolate, which is a result of housing projects being focused too much on functionalism. Through its analysis of Hundertwasser's housing projects, one of the objectives of this study is to contribute to a new design paradigm being called for today, including for housing projects to be more ecological and environmental-friendly. By motivating architects and appealing to their clients, this study hopes to motivate those involved in various housing projects to think progressively. Such an attitude change could assist in transforming and thus enhancing the overall living environment in Korea.

• 한국통신학회논문지
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• 제41권9호
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• pp.1060-1068
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• 2016

연결정보만을 이용하는 range-free 측위 기법의 성능은 이동성을 갖는 무선 단말 움직임에 취약한 문제점이 있다. 본 논문은 실제 전파 환경을 고려한 실내 네트워크에서 베이지안 필터를 사용하여 실시간으로 움직이는 무선장치를 추적하는 두 가지 알고리즘을 제안하였다. 제안하는 알고리즘은 측정 모델의 선형성에 따라 Kalman filter 와 Markov Chain Monte Carlo (MCMC) particle filter를 적용하였다. Kalman과 MCMC particle filter 기반 알고리즘은 각각 무선단말 간 연결정보를, 이동 단말의 한 홉 간격 내 단말로부터 수신하는 신호의 세기 (RSS: received signal strength)와 연결정보를 혼합한 융합정보를 측정 모델로 사용하였다. 정확한 시뮬레이션을 위해 실내 쇼핑몰 지도를 구현한 네트워크 지형, 그리고 라디오 불규칙도 모델을 적용하였다. 또한, 장애물 존재 여부에 따라 라디오 불규칙도를 분류하였다. 성능평가를 위해 MATLAB 시뮬레이션을 수행하였으며, 기존 range-free 측위 기법보다 향상된 위치정확도를 확인하였다.

• Archives of Plastic Surgery
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• 제37권6호
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• pp.742-748
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• 2010

Purpose: The method of using ultrasound-assisted liposuction and excision of the remaining glandular tissue is the preferred method for treating gynecomastia and is currently used worldwide. Herein, this article described the role of ultrasound-assisted liposuction before a surgical excision in the treatment of gynecomastia. The cosmetic results were objectively evaluated. Methods: 11 patients (22 breasts) underwent ultrasoundassisted liposuction and suction-assisted lipectomy between April 2007 and January 2009. At the end of the liposuction, the remaining glandular tissue was removed through the incision used for liposuction. We evaluated the cosmetic results using ordinary scale methods on the basis of four categories (recurrence, symmetry, contour irregularity, and scar). Results: The volume of aspirates ranged between 50 and 200 cc per breast and the average weight of tissue removed by excision was 65g per breast. No complications were recorded. Regarding the cosmetic evaluation, the recurrence, contour irregularity, and scar were excellent, the symmetry was good, and the overall results represented all those cases were mostly excellent. Conclusion: Ultrasound-assisted liposuction has many advantages in the treatment of gynecomastia. When excising the remaining glandular tissue, bleeding is decreased by the use of a tumescent technique. The glandular tissue is easily mobilized and excised after being "morselized" with ultrasound-assisted liposuction. The glandular tissue is simply dissected via the suction surface. Compared the residual mound of glandular tissue beneath the nipple and areola to the periphery, it facilitates precise control of the excision.

• 한국소음진동공학회논문집
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• 제26권6_spc호
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• pp.644-650
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• 2016

Track maintenance works based on track geometry recordings are essential to enhance the safety and comfort of railway transportation. Usually, the track irregularity has been measured by a special inspection trains which all were imported from abroad. Because the inspection train speed is limited under 160 km/h, it takes a long time to inspect railways and there is difficulty in daytime operation. To solve this problem, we started to develop a track geometry measuring system (TGMS) with measurement speed up to 300 km/h which can be installed in commercial vehicles such as HEMU-430X. In this paper, we introduce a newly developed inertial TGMS and propose two inertial navigation system (INS) algorithms (method A, B) for measuring track geometry. In order to investigate advantage and disadvantage of each algorithm, we performed vibration test of the TGMS, which was simulated by 6-axis shaking table. Through the vibration test, we analyzed the influence of vehicle vibration on the TGMS which will be installed on bogie frame. To the vibration test, two methods satisfied the required accuracy of track geometry measurement under the level of the actual vehicle vibration of HEMU-430X train. Theoretically, method A is sensitive to vehicle vibration than method B. However, HEMU-430X's bogie vibration frequency range is out of interest range of measurement system. Therefore, method A can also apply the HEMU-430X train.

• 한국학교보건학회지
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• 제9권1호
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• pp.69-75
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• 1996

The aim of this study is to find out the correlations between heaith behaviours of young people and the relationships with social factors, which can be helpful for the development of health promotion programmes for youths. The main socializing arenas influencing children's development of health and health behaviour are school, peers and parents. In this study, the selected social factors are based on these arenas. And the following seven health-related behaviours were selected: smoking, drinking alcohol, drinking coffee, irregularity of taking main meals, regular exercise, brushing teeth, and use of medicine for nourishment or restoratives. These health behaviours categorized into two groups; health- promotiong and health-damaging behaviours. The results were summarized as follows; Significant positive correlations were found between health damaging behaviours-drinking alcohol, coffee, smoking, irregularity of main meals, drinking alcohol. But, No consistently significant correlations were revealed among health promoting behaviours and between health promoting and health damaging behaviours. If total group were devided into four groups by gender and grade, these correlations were a little weak. Although such division, the correlations among health damaging behaviours were still significant. The result is also found that health behavious and various social factors were strongly correlated. Particulary, health damaging behaviours showed a consistent correlation with social factors. This consiatensy was simillar to the figure of other contries in Europe. In conclusion, a more comprehensive explanation on health behaviour bacame possible if the analysis on the correlations were made by dividing health behavious into "health-promotion" and "health- damaging". And the health promotion programmes can be more effective when they focus on the correlation of health behavious and inter-relationships between health behavious and various social factors, rahter than focus on individual behavious.

• Wind and Structures
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• 제27권6호
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• pp.399-416
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• 2018

In order to reveal the independent relationship between track irregularity and wind loads, the stochastic characteristics of train-bridge coupling systems subjected to wind loads were investigated by the multi-sample calculation. The vehicle was selected as 23 degrees of freedom dynamical model, and the bridge was described by three-dimensional finite element model. It was assumed that the wind loads were random processes with strong spatial correlation, while the track irregularities were stationary random ones. As a case study, a high-speed train running on a cable-stayed bridge subjected to wind loads was studied. The effect of rail irregularities was deemed to be independent of the effect of wind excitations on the coupling system in the same wind circumstance for the same project, leading to the conclusion that the effect of wind loads and moving vehicle could be calculated separately. The variance results of the stochastic responses of vehicle-bridge coupling system under the action of wind loads and rail irregularities together were equivalent to the sum of the variance of the responses induced by each excitation. Therefore, when one of the input excitations is different, only the effect of changed loads needs to be assessed. Moreover, the new calculated results were combined with the effect of unchanged loads to present the stochastic response of coupling system subjected to the different excitations, reducing the cost of computations. The stochastic characteristics, the CFD (cumulative distribution function) of the coupling system with different wind velocities, vehicle speed, and vehicle marshalling were studied likewise.

• 대한건축학회논문집:구조계
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• 제36권3호
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• pp.121-128
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• 2020

In this paper, the ASCE 7 equivalent static approach for seismic design of non-structural elements is critically evaluated based on the measured floor acceleration data, theory of structural dynamics, and linear/nonlinear dynamic analysis of three-dimensional building models. The analysis of this study on the up-to-date database of the instrumented buildings in California clearly reveals that the measured database does not well corroborate the magnitude and the profile of the floor acceleration as proposed by ASCE 7. The basic flaws in the equivalent static approach are illustrated using elementary structural dynamics. Based on the linear and nonlinear dynamic analyses of three-dimensional case study buildings, it is shown that the magnitude and distribution of the PFA (peak floor acceleration) can significantly be affected by the supporting structural characteristics such as fundamental period, higher modes, structural nonlinearity, and torsional irregularity. In general, the equivalent static approach yields more conservative acceleration demand as building period becomes longer, and the PFA distribution in long-period buildings tend to become constant along the building height due to the higher mode effect. Structural nonlinearity was generally shown to reduce floor acceleration because of its period-lengthening effect. Torsional floor amplification as high as 250% was observed in the building model of significant torsional irregularity, indicating the need for inclusion of the torsional amplification to the equivalent static approach when building torsion is severe. All these results lead to the conclusion that, if permitted, dynamic methods which can account for supporting structural characteristics, should be preferred for rational seismic design of non-structural elements.

• Imaging Science in Dentistry
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• 제51권2호
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• pp.155-165
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• 2021

Purpose: This study aimed to evaluate changes of the alveolar bone and interdental bone septum of the mandibular incisors through cone-beam computed tomography (CBCT) after orthodontic treatment of mandibular dental crowding without dental extraction. Materials and Methods: The sample consisted of 64 CBCT images(32 pre-treatment and 32 post-treatment) from 32 adult patients with class I malocclusion and an average age of 23.0±3.9 years. The width and height of the alveolar bone and interdental septum, the distance between the cementoenamel junction (CEJ) and the facial and lingual bone crests, and the inclination of the mandibular incisors were measured. Results: The distance between the CEJ and the marginal bone crest on the facial side increased significantly (P<0.05). An increased distance between the CEJ and the bone crest on the facial and lingual sides showed a correlation with the irregularity index (P<0.05); however, no significant association was observed with increasing mandibular incisor inclination (P>0.05). The change in the distance between the CEJ and the marginal bone crest on the facial side was correlated significantly with bone septum height(P<0.05). Conclusion: Bone dehiscence developed during the treatment of crowding without extraction only on the incisors' facial side. Increasing proclination of the mandibular incisor was not correlated with bone dehiscence. The degree of dental crowding assessed through the irregularity index was associated with the risk of developing bone dehiscence. The interdental septum reflected facial marginal bone loss in the mandibular incisors.