• International Journal of Naval Architecture and Ocean Engineering
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• 제1권2호
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• pp.89-94
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• 2009

The current focus of development in industrial Computational Fluid Dynamics (CFD) is integration of CFD into Computer-Aided product development, geometrical optimisation, robust design and similar. On the other hand, in CFD research aims to extend the boundaries of practical engineering use in "non-traditional" areas. Requirements of computational flexibility and code integration are contradictory: a change of coding paradigm, with object orientation, library components, equation mimicking is proposed as a way forward. This paper describes OpenFOAM, a C++ object oriented library for Computational Continuum Mechanics (CCM) developed by the author. Efficient and flexible implementation of complex physical models is achieved by mimicking the form of partial differential equation in software, with code functionality provided in library form. Open Source deployment and development model allows the user to achieve desired versatility in physical modeling without the sacrifice of complex geometry support and execution efficiency.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.527-533
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• 2000

It is investigated that the characteristics of rotating cantilevered composite beam with a breathing crack. In the present study, the crack is modeled as a breathing crack which opens and closes with the motion of the unidirectional graphite-fiber reinforced polyimide beam. For the finite element analysis, the cracked element is modelled by the local flexibility matrix calculated on the basis of fracture mechanics using Castiligano theorem. Rotating beam is considered only transverse bending motion so that the element includes two degrees of freedom per node such as the transverse deflection and slope. The time history and frequency response function of the beam with a breathing crack are studied by Newmark direct time integration method and FFT(Fast Fourier Transform)simulation. Effects of various parameters such as the crack depths, crack locations, ply angles, volume fraction ratios, and rotating speeds of the beam are also studied. Numerical results indicate that it is more reliable to be modelled as a breathing crack than an open crack.

• The Plant Pathology Journal
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• 제37권6호
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• pp.505-511
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• 2021

Interaction of a pathogen with its host plant requires both flexibility and rapid shift in gene expression programs in response to environmental cues associated with host cells. Recently, a growing volume of data on the diversity and ubiquity of internal RNA modifications has led to the realization that such modifications are highly dynamic and yet evolutionarily conserved system. This hints at these RNA modifications being an additional regulatory layer for genetic information, culminating in epitranscriptome concept. In plant pathogenic fungi, however, the presence and the biological roles of RNA modifications are largely unknown. Here we delineate types of RNA modifications, and provide examples demonstrating roles of such modifications in biology of filamentous fungi including fungal pathogens. We also discuss the possibility that RNA modification systems in fungal pathogens could be a prospective target for new agrochemicals.

• 한국의학물리학회지:의학물리
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• 제2권1호
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• pp.3-16
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• 1991

Abstract. An area of particularly rapid technological growth in the last 15 years has been medical imaging (conventional X-ray, ultrasound, X-ray computed tomography (CT), magnetic resonance imaging (MRI). As the number and complexity of imaging studies rises, it becomes ever more important to distribute these images and the associated diagnoses in a timely and cost-effective fashion. The purpose of this paper is to describe the requirements for a future digital radiology system which will efficiently handle the large volume of images that generated, add new functionality to improve productivity of physicians, technologists, and other health care providers, and provide enough flexibility to allow the system to grow as medical image technology grows.

• Wind and Structures
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• 제16권1호
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• pp.1-23
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• 2013

The wind-induced transient response of internal pressure following the creation of a sudden dominant opening during the occurrence of high external pressure, in low-rise residential and industrial buildings was numerically investigated. The values of the ill-defined parameters namely the flow contraction coefficient, loss coefficient and the effective slug length were calibrated by matching the analytical response with the computational fluid dynamics predictions. The effect of a sudden i.e., "instantaneously created" windward opening in the Texas Technical University (TTU) test building envelope was studied for two different envelope flexibility-leakage combinations namely: (1) a quasi-statically flexible and non-porous envelope and (2) a quasi-statically flexible and porous envelope. The responses forced by creating the openings at different time leads/lags with respect to the occurrence of the peak external pressure showed that for cases where the openings are created in close temporal proximity to the peak pressure, the transient overshoot values of internal pressure could be higher than the peak values of internal pressure in the pre-sequent or subsequent resonant response. In addition, the influence of time taken for opening creation on the level of overshoot was also investigated for the TTU building for the two different envelope characteristics. Non-dimensional overshoot factors are presented for a variety of cavity volume-opening area combinations for (1) buildings with rigid/quasi-statically flexible non-porous envelope, and (2) buildings with rigid/quasi-statically flexible and porous envelope (representing most low rise residential and industrial buildings). While the factors appear slightly on the high side due to conservative assumptions made in the analysis, a careful consideration regarding the implication of the timing and magnitude of such overshoots during strong gusts, in relation to the steady state internal pressure response in cyclonic regions, is warranted.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1995년도 추계학술대회
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• pp.216-218
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• 1995

A new atrial pressures balancing method for moving actuator total artificial heart(TAH) without an extra compliance chamber is developed. The structural characteristics of the pendulous moving actuator have made it possible to compensate the left and right pump output difference by utilizing the interventricular air space as an internal compliance chamber in a pump housing. Furthermore, the balancing performance is increased through the improvement of the flexibility of part of the polyurathane housing. However, the increase of the flexibility of the housing causes a little loss of the cardiac output due to the reduction of active filling performance. In this paper, a good condition between the balance and pump output performance is evaluated by adjusting the air volume in the interventricular space through a series of in vitro experiment.

• Interdisciplinary Bio Central
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• 제3권2호
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• pp.7.1-7.6
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• 2011

Background: Published manuscripts are the main source of biological knowledge. Since the manual examination is almost impossible due to the huge volume of literature data (approximately 19 million abstracts in PubMed), intelligent text mining systems are of great utility for knowledge discovery. However, most of current text mining tools have limited applicability because of i) providing abstract-based search rather than sentence-based search, ii) improper use or lack of ontology terms, iii) the design to be used for specific subjects, or iv) slow response time that hampers web services and real time applications. Results: We introduce an advanced text mining system called PubMine that supports intelligent knowledge discovery based on diverse bio-ontologies. PubMine improves query accuracy and flexibility with advanced search capabilities of fuzzy search, wildcard search, proximity search, range search, and the Boolean combinations. Furthermore, PubMine allows users to extract multi-dimensional relationships between genes, diseases, and chemical compounds by using OLAP (On-Line Analytical Processing) techniques. The HUGO gene symbols and the MeSH ontology for diseases, chemical compounds, and anatomy have been included in the current version of PubMine, which is freely available at http://pubmine.kobic.re.kr. Conclusions: PubMine is a unique bio-text mining system that provides flexible searches and analysis of biological entity relationships. We believe that PubMine would serve as a key bioinformatics utility due to its rapid response to enable web services for community and to the flexibility to accommodate general ontology.

• 한국의상디자인학회지
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• 제17권4호
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• pp.77-90
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• 2015

This study is to designed to provide foundation for knit design which can apply the thickness and flexibility of jacquard knit by analyzing and comparing mechanical properties of 7 types of jacquard (normal jacquard, bird's eye jacquard, floating jacquard, tubular jacquard, ladder's back jacquard, blister jacquard, transfer jacquard) widely used in knit design to achieve the results. The sample was projected by using 7 gauge and SES-122S type computer knitting machine house tooth pattern with two colors were applied to 7 types of jacquard using Acrylic/Wool(30%/70%) $2/50.5^{\prime}s{\times}4ply\;yarn$ by Shimaseiki MFG., Ltd computer knitting machine. The mechanical properties of 7 types of jacquard samples were measured using KES-FB (Kawabata Evaluation System for Fabric, Kata Tech Co. Ltd). HV(Hand Value) and THV (Total Hand Value) were calculated by using the formula of KN-402-KT and KN-301-WINTER respectively. The measurements were evaluated by 0-to-5 rating scale. As result, the floating jacquard was found to have excellent drape, making it suitable for express feminine silhouette with its most flexible and smooth touch. On the other hand, bird's eye jacquard is adequate for a suit jacket and coat regarding its excellent volume and flexibility. Blister jacquard and tubular jacquard are thick, heavy and stiff knit and both are suitable for simple box-style design. Ladder's back jacquard, however, is more appropriate for expressing the design of feminine charm and voluminous design. Based on the result of this study, it is supposed to provide basic information for development of knit industry regarding jacquard knit by designing the creative knit wear with high production efficiency.

• 한국산학기술학회논문지
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• 제21권9호
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• pp.9-16
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• 2020

무선충전 기술은 사용자가 선 없이 충전할 수 있는 편리함의 이점으로 많은 모바일 전자기기의 필수요소로 자리 잡게 되었고, 지속적인 연구 개발에 의해 다양한 무선충전 시스템이 제안되고 있다. 대표적인 무선충전 시스템으로는 송수신 코일의 배치와 충전효율의 상관관계를 고려하여, 송수신 코일을 근거리 평면에 배치한 2D 평면 코일 시스템이 주로 사용되어왔다. 최근에는 평면으로 넓은 공간을 차지하는 2D 코일시스템에 높이구배를 주어, 공간을 효율적으로 사용하기 위한 3차원 코일시스템이 제안되고 있다. 하지만, 3차원 코일시스템은 2D 코일시스템에 비해 충전효율이 낮고, 특히 송수신 코일간의 거리가 멀어질수록 전력전송 효율이 급격하게 저하되는 경향이 있다. 본 논문에서는 기존 3차원 코일시스템의 단점인 낮은 충전효율과 충전자유도를 개선하기 위해 새로운 무선충전 시스템 설계를 제안한다. 3차원 형상으로 송신코일과 수신코일을 설계하였고, 이때 송신코일 내부에 독립된 송신코일을 추가로 구성한 이중 송신코일 구조를 제안하여 전송효율과 자유도를 개선할 수 있었다. 측정실험 결과, 107 kHz 동작주파수에서 송수신 코일의 거리가 8 mm일 때 제안한 시스템의 효율은 40.10 %로 기존 코일의 최대전송효율인 20.5 %에 비해 크게 증가했다. 본 논문에서 제안한 3차원 이중송수신 코일시스템은 실제 무선충전 시스템 설계 시 다양한 디자인의 무선충전 시스템 설계 및 충전효율 개선에 기여할 것으로 기대된다.

• 한국전자거래학회지
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• 제18권3호
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• pp.17-43
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• 2013

본 연구는 빅데이터의 구성요소(Volume, Variety, Velocity, Complexity)가 가지는 속성을 정의하여 상황인식에 관한 재난대응 활동의 의사결정에 미치는 영향을 실증적으로 분석하였다. 이를 위하여 빅데이터가 가지는 속성과 상황인식 간의 가설을 설정하였고, 시각화가 상황인식을 통한 의사결정간의 인과관계를 조절하는 효과가 있는지를 확인하였다. 분석을 위해 안전행정부, 소방방재청, 시도 및 시군구 재난관리과를 대상으로 설문 332부를 수집하였으며, 불성실한 응답 12부를 제외함으로써 320부를 분석에 사용하였다. 연구 결과, 첫째 빅데이터가 가지는 속성 중 누적성, 확장성, 유연성, 실시간성, 분석성, 융합성은 재난관리 담당자의 상황인식에 유의한 영향을 미쳤으나, 다양성과 비정형성은 영향을 미치지 못하였다. 둘째, 재난관리 담당자의 상황인식은 재난대응 활동의 의사결정에 유의한 영향을 미쳤다. 셋째, 시각화는 상황인식과 재난대응 활동의 의사결정간에 조절효과가 있는 것으로 분석되었다.