• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.5
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• pp.57-72
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• 1999

Traditional theories of the tensile failure of paper have assumed that uniform strain progresses throughout the sheet until an imperfection within the structure causes a catastrophic break. The resistance to tensile elongation is assumed to be elastic , at first, throughout the structure, followed by an overall plastic yield. However, linear image strain analysis (LISA) has demonstrated that the yield in tensile loading of paper is quite non-uniform throughout the structure, Traditional theories have failed to define the flaws that trigger catastrophic failure. It was assumed that a shive or perhaps a low basis weight area filled that role. Studies of the fracture mechanics of paper have typically utilized a well-defined flaw around which yield and failure could be examined . The flaw was a simple razor cut normal to the direction of tensile loading. Such testing is labeled mode I analysis. The included fla in the paper was always normal to the tensile loading direction, never at another orientation . However, shives or low basis weight zones are likely to be at random angular orientations in the sheet. The effects of angular flaws within the tensile test were examined. The strain energy density theory and experimental work demonstrate the change in crack propagation from mode I to mode IIas the initial flaw angle of crack propagation as a function of the initial flaw angle is predicted and experimentally demonstrated.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.11a
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• pp.251-254
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• 2009

본 논문에서는 고해상도 동영상의 실시간 복호화를 위하여 Application Specific Instruction-set Processor (ASIP)기술을 이용하여 H.264/AVC 고속 병렬 복호화기를 설계하였다. 우선, 하드웨어에 최적화된 구조로 복호화기를 설계하고 LISA로 기술한 멀티미디어 전용 명령어를 명령어 집합에 추가하였다. 이렇게 설계한 고속 H.264/AVC 복호화기는 사이클 기반 시뮬레이터에서 성능을 측정한 결과 기존 대비 약 35%의 복호화 사이클 감소를 보였다. 추가적인 성능 향상을 위해, 앞서 설계한 고속복호화기를 여러 개 사용하여 병렬 H.264/AVC 복호화기를 설계하였다. 병렬 복호화기는 여러 매크로블록을 동시에 복호화 처리함으로써 복호화기의 성능을 대폭 향상시켰다. 병렬 복호화기는 고속 복호화기 대비 약 75%의 복호화 사이클이 감소하였다. 이에 고해상도 동영상의 실시간 복호화를 위한 H.264/AVC 고속 병렬 복호화기의 설계 방법을 제시하고자 한다.

• Steel and Composite Structures
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• v.15 no.6
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• pp.679-703
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• 2013

This paper presents experimental investigations of the fundamental behavior of concrete filled steel tube (CFT) beam-columns under fire loading. A total of thirteen specimens were tested to determine the axial force-moment-curvature-temperature behavior of CFT beam-columns. The experimental approach involved the use of: (a) innovative heating and control equipment to apply thermal loading and (b) digital image correlation with close-range photogrammetry to measure the deformations (e.g., curvature) of the heated region. Each specimen was sequentially subjected to: (i) constant axial loading; (ii) thermal loading in the expected plastic hinge region following the ASTM E119 temperature-time T-t curve; and (iii) monotonically increasing flexural loading. The effects of various parameters on the strength and stiffness of CFT beam-columns were evaluated. The parameters considered were the steel tube width, width-tothickness ratio, concrete strength, maximum surface temperature of the steel tube, and the axial load level on the composite CFT section. The experimental results provide knowledge of the fundamental behavior of composite CFT beam-columns, and can be used to calibrate analytical models or macro finite element models developed for predicting behavior of CFT members and frames under fire loading.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.3 s.116
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• pp.91-103
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• 2006

조경설계의 도구로서 컴퓨터 드로잉 기술은 핸드드로잉이 제공할 수 없었던 많은 이점을 제공하여 주며, 그 중요성은 현 미국 조경설계 실무 및 교육에서 점점 커 가고 있는 실정이다. 하지만 조경교육 측면에서 핸드드로잉과 컴퓨터 드로잉을 어떻게 균형을 맞추어야 하는지 쉽지 않은 논쟁거리를 제공한다. 이러한 미국 조경교육계의 고민은 미국에 국한된 문제가 아니라 한국 조경교육에서도 진지하게 고려되어야 되는 문제로 보인다. 본 연구는 미국 달라스시와 포트워쓰시를 포함한 미 텍사스주 북부에 위치한 설계사무소에 근무하는 조경기술사를 취득한 조경설계가들을 대상으로 실시한 설문을 통하여 조경실무에 있어서 핸드드로잉과 컴퓨터 드로잉의 역할에 대하여 조사하였다. 달라스시와 포트워쓰시는 Carter & Burgess, HOK, Mesa Design Group, SMR, SWA Group, TBG Partners등 미국의 대표적인 조경설계사무소 대부분이 본사 혹은 지역사무소를 두고 있는 미 남부의 대표적인 금융, 건(축)설 분야의 대표적인 쌍둥이 도시로 알려져 있다. 설문조사 결과, 몇몇 개인 특성들이 일상적인 조경설계에 있어서 핸드드로잉과 컴퓨터 드로잉의 중요성에 대한 인지와 관계가 있는 것으로 나타났다. 또한 컴퓨터 드로잉 기술이 일상적인 조경설계 과정에서 빈번하게 사용되고 있음에도 불구하고, 핸드드로잉만이 제공할 수 있는 고유 역할이 있는 것으로 나타났다. 특히 조경디자인 아이디어를 발전시키는 과정에 핸드드로잉 기법이 중요한 역할을 하는 것으로 나타났다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.2
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• pp.43-54
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• 2013

In an attempt to regain function and aesthetics in the craniofacial region, different biomaterials, including titanium, hydroxyapatite, biodegradable polymers and composites, have been widely used as a result of the loss of craniofacial bone. Although these materials presented favorable success rates, osseointegration and antibacterial properties are often hard to achieve. Although bone-implant interactions are highly dependent on the implant's surface characteristics, infections following traumatic craniofacial injuries are common. As such, poor osseointegration and infections are two of the many causes of implant failure. Further, as increasingly complex dental repairs are attempted, the likelihood of infection in these implants has also been on the rise. For these reasons, the treatment of craniofacial bone defects and dental repairs for long-term success remains a challenge. Various approaches to reduce the rate of infection and improve osseointegration have been investigated. Furthermore, recent and planned tissue engineering developments are aimed at improving the implants' physical and biological properties by improving their surfaces in order to develop craniofacial bone substitutes that will restore, maintain and improve tissue function. In this review, the commonly used biomaterials for craniofacial bone restoration and dental repair, as well as surface modification techniques, antibacterial surfaces and coatings are discussed.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.53.2-53.2
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• 2017

Stochasitc gravitational wave background (SGWB) is expected to be contributed by primordial sources (e.g. inflation signature) and astrophysical sources (e.g., incoherent superposition of a large numbers of compact binary inspirals throughout in the Universe). Theoretically, SGWB is predicted to span in a broad frequency range between less than nHz up to kHz. Many gravitational-wave (GW) detectors such as LIGO or LISA aim to detect or constrain SGWB in different frequency band that is most sensitive for each detector. In this talk, we focus on the prospectives of constraining the energy density of SGWB between 0.1-10 Hz. We introduce the characteristics of SGWB and representative models for primordial and astrophysical sources. Then, we propose a signal extraction scheme to detect SGWB using one or several omni-directional GW detectors such as SLGT(Superconducting Low-frequency Gravitational-wave Telescope). Considering SLGT sensitivity, we discuss how to observe SGWB in 0.1-10 Hz if we have SLGT network. Finally, we highlight interesting SGWB models that can be constrained in 0.1-10 Hz with SLGT.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.52.1-52.1
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• 2017

The discovery of GW150914, black hole - black hole merger via gravitational waves (GWs) opened a new window to observe the Universe. GW frequencies from heavenly bodies and early Universe are expected to span between sub-nHz up to kHz. At present, GW detectors on Earth (LIGO, Virgo, KAGRA, LIGO-India) aims frequency ranges between 10-2000 Hz. The space-borne GW detector and Pulsar Timing Array targets mHz and nHz sources. Starting in March 2017, the KKN (KASI-KISTI-NIMS) collaboration launched a pilot study of SLGT (Superconducting Low-frequency Gravitational-wave Telescope). This project is funded by NST (Korea Institute of Science and Technology). The main detection bands expected for SLGT ranges between 0.1-10Hz, which is complementary of LIGO-type detectors and LISA for multi-band GW observation. We will present an overview of the SLGT project and report the status of the NST pilot study. We will also present prospective of GW astronomy with SLGT.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.4
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• pp.336-340
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• 2018

Foreign body ingestions pose a significant health risk in children. Neodymium magnets are high-powered, rare-earth magnets that is a serious issue in the pediatric population due to their strong magnetic force and high rate of complications. When multiple magnets are ingested, there is potential for morbidity and mortality, including gastrointestinal fistula formation, obstruction, bleeding, perforation, and death. Many cases require surgical intervention for removal of the magnets and management of subsequent complications. However, we report a case of multiple magnet ingestion in a 19-month-old child complicated by gastroduodenal fistula that was successfully treated by endoscopic removal and supportive care avoiding the need for surgical intervention. At two-week follow-up, the child was asymptomatic and upper gastrointestinal series obtained six months later demonstrated resolution of the fistula.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1159-1166
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• 2012

Research on radiation oncologists has indicated that there is a shortage in supply of specialist workers in this field internationally, and also within Australia. However, there are no current estimates as to what the future Australian radiotherapy workforce will look like. This paper aims to review the current status and capacity of the three main disciplines that make up the radiation oncology workforce in Australia and project the workforce supply and demand for 2014 and 2019. Using data on the workforce from a survey of all radiotherapy facilities operating in Australia in 2008 a workforce model was constructed. This study found that there will be a future shortfall of radiation oncologists, radiation therapists and radiation oncology medical physicists working in radiation oncology treatment. By 2014 there will be 109 fewer radiation oncologists than what will be demanded, and by 2019 this figure will increase to a shortfall of 155 radiation oncologists. There was a projected shortfall of 612 radiation therapists by 2014, with this figure slightly decreasing to a shortfall of 593 radiation therapists in 2019. In 2014, there was projected to be a deficit of 104 radiation oncology medical physicists with a persisting shortfall of 78 in 2019. This future projected shortage highlights the need for radiation oncology workforce planning.

• Journal of Korean Library and Information Science Society
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• v.18
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• pp.91-138
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• 1991

The paper describes the application areas of the hypertext and the relevance of hypertext principles to the information retrieval system. As to the techniques of the hypertext information retrieval the various navigation method including a guided tour, a history list, a browser, a book-mark, etc. are discussed. The query system is considered as the other technique to be integrated into the hypertext system for the enhancement of the interactive function of the information retrieval. Based on the theoretical background, a conceptual model of hypertext information retrieval system was constructed using GUIDE which was developed by P.J. Brown of Kent University. 16 bibliographic records from LISA of 1991(June) were used for the illustration of the basic operation of the system. Though the study could not reach the implementation level due to the absolute constraints of the time and experimental environments, further efforts will continue to develop a prototype system of a hypertext information retrieval. A few conclusions can be derived from the study : (1) The integration of the hypertext into the information retrieval system can be justified by permitting the end-users to have much stronger and more flexible interaction with the system. (2) The more the degree of the sofistication of the existing information retrieval system is the more the possibility of the development of an effective and user-oriented information retrieval system will be greater by integrating guide as a front end system to the underlying software. (3) The deep knowledge about the functions of information retrieval which can be enhanced by the hypertext could be acquired by the information retrieval specialists.