• Geomechanics and Engineering
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• 제28권6호
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• pp.585-598
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• 2022

The monopile-friction wheel hybrid foundation is an innovative solution for offshore structures which are mainly subjected to large lateral eccentric load induced by winds, waves, and currents during their service life. This paper presents an extensive numerical analysis to investigate the lateral load and moment bearing performances of hybrid foundation, considering various potential influencing factors in sand-overlaying-clay soil deposits, with the complex lateral loads being simplified into a resultant lateral load acting at a certain height above the mudline. Finite element models are generated and validated against experimental data where very good agreements are obtained. The failure mechanisms of hybrid foundations under lateral loading are illustrated to demonstrate the effect of the friction wheel in the hybrid system. Parametric study shows that the load bearing performances of the hybrid foundation is significantly dependent of wheel diameter, pile embedment depth, internal friction angle of sand, loading eccentricity (distance from the load application point to the ground level), and the thickness of upper sandy layer. Simplified empirical formulae is proposed based on the numerical results to predict the corresponding lateral load and moment bearing capacities of the hybrid foundation for design application.

• Spatial Information Research
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• 제20권4호
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• pp.29-36
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• 2012

최근 도시와 도시간의 물류량 증가로 인하여 교통혼잡비용이 증가하고, 기후변화협약에 따른 이산화탄소 감축이 의무화됨에 따라 저탄소 화물운송체계 개념이 소개되었다. 연료소비량 및 탄소배출량을 고려한 화물운송계획을 수립하기 위해서는 현실의 도로 기하정보를 표현하는 3차원 도로망도가 필수적이다. 본 연구는 화물운송의 주요대상인 도시와 도시간의 간선도로를 중심으로 지형 및 도로구조물을 고려하기 위하여 기존 2차원 교통주제도와 수치표고모델을 이용하여 도로의 실제 기하정보를 반영하는 3차원 도로망도 모델을 제안한다. 제안 모델은 실험 도로구간(평택항-의왕IC)을 대상으로 구축하고 GPS/INS 측량을 통해 구축한 3차원 도로망도가 도로의 기하정보를 잘 표현함을 검증하였다(RMSE=0.87m). 또한, 연료소모량 시뮬레이션을 통해 기존의 2차원 도로망도에 비해 제안모델이 현실도로의 연료소모량을 효과적으로 반영함을 알 수 있었다. 본 연구를 통해 복잡한 도로의 3차원 기하정보를 반영하여 에너지 및 환경문제를 효과적으로 고려할 수 있는 Green-ITS기반의 화물 경로계획 및 네비게이션 시스템 개발이 가능할 것이다.

• 대한소아치과학회지
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• 제43권1호
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• pp.79-84
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• 2016

Myoepithelioma는 타액선에 발생하는 드문 질환이다. Myoepithelioma는 소아 및 청소년보다 성인에서 호발한다. 구개부의 종창을 주소로 8세 여환이 본원으로 내원하였다. 환아의 나이와 상대적으로 큰 종양의 크기를 고려하여, 전신 마취 하에 구개부 점막 조직을 보존하는 보존적인 외과적 절제술이 시행되었다. 수술 부위의 치유가 적절히 일어났으며, 40개월의 관찰기간 동안 재발되지 않았다. 주변의 구개부 조직을 보존하는 최소 침습적 제거술은 소아에서 발생되는 myoepithelioma의 치료시 유용할 것으로 사료되었다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 춘계학술대회
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• pp.249-251
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• 2012

증강현실은 가상현실과 달리 현실 세계를 바탕으로 가상정보를 제공함으로, 보다 향상된 현실감과 상호작용을 가능케 하는 장점이 있다. 본 논문에서는 스마트폰이나 테블릿 PC에서 선박 3D 모델을 시각화하는 증강현실 기반의 선박설계 시각화 시스템을 제안한다. 제안된 시스템은 Contour 기법으로 모서리점을 추출하고, Harris의 코너점 검출기로 대표 특징점을 추출하여 설계도면 데이터베이스를 구축한다. SURF 알고리즘을 이용하여 카메라로부터 입력받은 설계도면 영상에서 대표 특징점들을 추출하여 서버에 저장된 설계도면 DB의 특징점과 설계도면을 매칭하여 인식한다. 인식된 설계도면은 모바일 기기에서 3D 선박 구조물을 증강하여 시각화한다. 기존의 2D로 이루어지는 영업설계에 비해 선박의 이해가 용이하며 설계기간을 단축시키는 효과로 영업경쟁력이 향상될 것으로 기대된다.

• 한국도로학회논문집
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• 제10권2호
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• pp.125-133
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• 2008

차량의 주행속도는 설계일관성을 평가하는 주요한 척도로 활용되며 그 중 곡선반경은 여러 연구에서 공통적으로 제시한 주된 요인으로 나타났다. 이에 본 연구에서는 복합선형에서 설계속도별 적정 평면곡선반경 범위기준을 정립하고 운전자의 인지 행태를 나타낼 수 있는 인지반경을 정립하여 입체선형에서 적합한 평면곡선반경을 제시하고자 한다. 첫째, 본 연구에서는 저속차량의 방해요소를 최소화하기 위하여 입체선형을 고려한 도로의 임의지점에서 횡방향 미끄럼 마찰계수와 주행방향 미끄럼 마찰계수를 동시에 고려하여 설계속도와 종단경사별 평면곡선반경을 제시하였다. 둘째, 본 연구에서는 곡선부 인지반경을 통하여 평면 곡선부와 편평한 종단경사가 조합된 경우, 평면 곡선부와 종단곡선부가 조합된 경우를 비교한 후, 곡선부 인지반경을 산정하여 설계속도별 적정 평면곡선반경과 인지반경 비율을 제시하였다.

• Asian review of World Histories
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• 제4권1호
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• pp.3-34
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• 2016

This introduction is both a statement of a research problem and an account of the first research results for its solution. As more historical databases come online and overlap in coverage, we need to discuss the two main issues that prevent 'big' results from emerging so far. Firstly, historical data are seen by computer science people as unstructured, that is, historical records cannot be easily decomposed into unambiguous fields, like in population (birth and death records) and taxation data. Secondly, machine-learning tools developed for structured data cannot be applied as they are for historical research. We propose a complex network, narrative-driven approach to mining historical databases. In such a time-integrated network obtained by overlaying records from historical databases, the nodes are actors, while thelinks are actions. In the case study that we present (the world as seen from Venice, 1205-1533), the actors are governments, while the actions are limited to war, trade, and treaty to keep the case study tractable. We then identify key periods, key events, and hence key actors, key locations through a time-resolved examination of the actions. This tool allows historians to deal with historical data issues (e.g., source provenance identification, event validation, trade-conflict-diplomacy relationships, etc.). On a higher level, this automatic extraction of key narratives from a historical database allows historians to formulate hypotheses on the courses of history, and also allow them to test these hypotheses in other actions or in additional data sets. Our vision is that this narrative-driven analysis of historical data can lead to the development of multiple scale agent-based models, which can be simulated on a computer to generate ensembles of counterfactual histories that would deepen our understanding of how our actual history developed the way it did. The generation of such narratives, automatically and in a scalable way, will revolutionize the practice of history as a discipline, because historical knowledge, that is the treasure of human experiences (i.e. the heritage of the world), will become what might be inherited by machine learning algorithms and used in smart cities to highlight and explain present ties and illustrate potential future scenarios and visionarios.

• Preventive Nutrition and Food Science
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• 제12권3호
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• pp.160-166
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• 2007

Response surface methodology (RSM) was used for the optimization of the baking process of cookies made with onion powders (onion cookie). Experiments were carried out according to a central composite design, selecting onion powder content $(1.15{\sim}8.86%)$ and baking temperature $(155.9{\sim}184.1^{\circ}C)$ as independent variables and pH, titratable acidity, moisture content, density, spread factor, CIE color parameters $(L^{\ast}-$, $a^{\ast}-$, and $b^{\ast}-values)$, and hardness as response variables. pH decreased with increasing amount of onion powder and baking temperature. Moisture content also decreased as the baking temperature increased. $L^{\ast}-$ and $b^{\ast}-values$ decreased but $a^{\ast}-values$ increased with increasing onion content and baking temperature. Most polynomial models developed by RSM were highly effective to describe the relationships between the studied factors and the responses. Overall optimization, conducted by overlaying the contour plots under investigation, was able to point out the optimal range of the independent variables within which the six responses were simultaneously optimized. The point chosen as representative of this optimal region corresponded to 4.01% onion powder content and $161.84^{\circ}C$ baking temperature. The predicted dependent or response values in the optimal region were: pH＝6.87, moisture content＝2.77%, $L^{\ast}-value＝68.45$, $a^{\ast}-value＝1.98$, $b^{\ast}-value＝34.64$, and spread factor＝9.41.

• 복식
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• 제17권
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• pp.137-148
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• 1991

The use of bark cloth, made of the inner bark of certain trees, was widespread along tropical zones from the Africa to the Hawaii encompassing the globe. They include Malaysia, Indonesia, New Guinea, Polynesian Islands and South America. Among them the Hawaiian bark cloth, named Kapa(pronounced as tapa) was rated as the best quality and most admired. It has variety in designs and colors as well as the most sophistcated production methods. The distinct processes of kapa making are composed of two stages. The first is called first beating and it is a preparatory stage to beat the sea-water soaked bast. It was done with a round beater on a stone anvil. The second beating process was carried out with the squared beater and wooden anvil. The strips from the first beating was soaked again in the water and then beaten lightly to break up fibers. The craftmen laid a bundle of strips over the anvil and beat it into pieces of kapa. The second beater of Hawaii was the most characteristic one among bark cloth producing countries. On their surfaces were the engraved patterns, which were creation of theirs. These distinguished designs enabled them to produce the kapa with the thinner and finer texture and an elaboration of impressed designs known as "watermaks". The Hawaiian culture was self-sufficient one : Everything they used was of their own creation until 19th century. Among their inventions of printing designs on kapa are three most important and distinguished processes. They are the overlaying, the cord snapping and the block printing techniques. Their inventiveness as well as self sufficient environment made it possible to develop their fine art of the kapa making. It is said that the mass producing and cheap western technology of loom forced them to gradually abandon their traditional art and as a result this fine and valuable legacy of Hawaiian traditional kapa making technique is all but disappeared. However it is encouraging and heart warming to find that some of the people as well as specialized researchers pined together to form a group to try to reproduce the old kapa and study the traditional art. They consider the kapa as an expression of the ethnic identity with Hawaii's heritage as well as valuable art of human history.

• Journal of Advanced Marine Engineering and Technology
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• 제41권1호
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• pp.21-30
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• 2017

현재 국내에서 공장 보수용접이 가장 많이 이루어지고 있는 선박 엔진 부품은 피스톤 크라운과 배기밸브이다. 또한 선박 엔진 밸브와 크랭크 축 등의 경우에는 신규 부품에서도 성능향상을 위해 표면개질방법으로 오버레이 용접이 시공되고 있다. 용착률을 높이는 고능률 오버레이 용접 공정으로 Hot Wire GTAW, Cold Tandem GMAW, Band Arc SAW, Tandem SAW법이 개발되어 있고, 용사방법으로 PTA공정이 현장에서 많이 시공되고 있다. 입열량 제어가 용이한 공정으로 GMAW-Pulse, CMT 용접공정이 있다. 엔진 배기밸브의 보수를 위한 오버레이공정에서 열영향부에 가까운 모재 내에 액화균열이 발생하는 경우가 있어 주의를 요한다. GMAW-Pulse 공정과 CMT공정에서는 입열량 제어가 용이하여 높은 용착속도를 유지하면서도 액화균열의 발생 없이 엔진 밸브의 보수 또는 표면 개질 목적으로 시공이 가능하다. 최근에 국내에서 고능률 용접 공정으로 선박엔진의 보수 또는 표면 개질 목적으로 사용 가능한 Super-TIG 용접공정이 개발되어 있다. 이 공정은 아크를 플라즈마 스트림이라고 보고 전류증가에 따라 커지는 아크압력을 막으면서도 용가재의 용융 효율이 극대화 되도록 폭이 큰 C형의 오목한 용가재를 발명하여 용착률을 획기적으로 향상시킨 용접공정이다.

• Journal of Ecology and Environment
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• 제35권4호
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• pp.323-329
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• 2012

The Standardized Precipitation Index (SPI) is a widely used drought index to provide good estimations of the intensity, magnitude and spatial extent of droughts. The objective of this study was to analyze the spatial pattern of drought by SPI index. In this paper, the patterns of drought hazard in Iran are evaluated according to the data of 40 weather stations during 1967-2009. The influenced zone of each station was specified by the Thiessen method. It was attempted to make a new model of drought hazard using GIS. Three criteria for drought were studied and considered to define areas of vulnerability. Drought hazard criteria used in the present model included: maximum severity of drought in the period, trend of drought, and the maximum number of sequential arid years. Each of the vulnerability indicators were mapped and these as well as a final hazard map were classified into 5 hazard classes of drought: one, slight, moderate, severe and very severe. The final drought vulnerability map was prepared by overlaying three criteria maps in a GIS, and the final hazard classes were defined on the basis of hazard scores, which were determined according to the means of the main indicators. The final vulnerability map shows that severe hazard areas (43% of the country) which are observed in the west and eastern parts of country are much more widespread than areas under other hazard classes. Overall, approximately half of the country was determined to be under severe and very severe hazard classes for drought.