• Proceedings of the Korea Information Processing Society Conference
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• 2000.10b
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• pp.1361-1364
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• 2000

STC104 라우터칩은 점대점 방식으로 자료를 전송하도록 설계되어 있어서 하드웨어 기반의 멀티캐스팅을 할 수 없다. 멀티캐스팅을 하기 위해서는 각 노드간의 관계를 파악하여 동시에 데이터를 전송하는 알고리즘을 개발하여 소프트웨어적인 방법을 이용해야 한다. 본 논문에서는 멀티캐스팅 트리를 이용하여 STC104 라우터칩으로 이루어진 그물 구조 망에서 멀티캐스링 전송 알고리즘을 제시하고 그 성능을 실험하였다. 멀티캐스팅 트리를 이용한 전송 성능은 전체 hop수가 적을수록 그리고 발원 노드가 전송할 때 적절히 분산시켜 전송할수록 개선된 성능이 나타났다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.43-44
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• 2001

프레임에 그물감을 부착하여 구성되어 있는 가두리 시설은 파랑과 조류 등에 의해 유체력을 많이 받기 때문에, 만 입구 또는 외만에 설치하는 경우에는 작용 유체력에 의하여 이것을 계류하고 있는 계류삭이 절단되거나 고정용 닻이 끌리게 되며 프레임 끼리 서로 충돌함으로써 결국 구조물이 파손된다. 이와 같은 문제점을 해결하기 위해서는 파랑과 조류에 의해 발생되는 유체력에 충분히 견딜 수 있도록 시설물을 설계해야 한다. (중략)

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.7-11
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• 2001

The influence of temperature and calcium concentration on the gelation kinetics of purified Aigeok system has been investigated by small deformation oscillatory measurement. DE(degree of esterification) of the present sample was indicated of low methoxyl Aigeok polysaccharide by FT-IR. The calcium induced gelation of Aigeok has been studied. Both moduli reached the saturation value during the period of experiments. Rate constant increased with increasing calcium concentration, however above 4.08 mM calcium chloride caused a sudden drop in gel strength. The experimental result that the decrease in gel strength at high calcium concentration was seems to be phase separation or competitive inhibition between calcium ions. The storage and loss shear moduli decreased with increasing temperature. The rate constant of Aigeok system remarkably dropped above $35^{\circ}C$. Thus hydrogen bonding is prior to hydrophobic interaction for Aigeok molecule.

• Journal of radiological science and technology
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• v.40 no.4
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• pp.533-542
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• 2017

In diagnostic radiology, the imaging system has been changed from film/screen to digital system. However, the method for removing scatter radiation such as anti-scatter grid has not kept pace with this change. Therefore, authors have devised the indirect flat panel detector (FPD) system with net-like lead in substrate layer which can remove the scattered radiation. In clinical context, there are many radiographic examinations with angulated incident X-ray. However, our proposed FPD has net-like lead foil so the vertical lead foil to the angulate incident X-ray would have bad effect on its performance. In this study, we identified the effect of vertical/horizontal lead foil component on the novel system's performance and improved the structure of novel system for clinical usage with angulated incident X-ray. Grid exposure factor and image contrast were calculated to investigate various structure of novel system using Monte Carlo simulation software when the incident X-ray was tilted ($0^{\circ}$, $15^{\circ}$, and $30^{\circ}$ from the detector plane). More photons were needed to obtain same image quality in the novel system with vertical lead foil only then the system with horizontal lead foil only. An optimal structure of novel system having different heights of its vertical and horizontal lead foil component showed improved performance compared with the novel system in a previous study. Therefore, the novel system will be useful in a clinical context with the angulated incident X-ray if the height and direction of lead foil in the substrate layer are optimized as the condition of conventional radiography.

• Korean Journal of Crystallography
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• v.13 no.1
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• pp.12-16
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• 2002

The complex [Ni(L)](BDC)·4H₂O (1) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[16,4,O/sup 1.18/,O/sup 7.12/] docosane; BDC = 1,3-benzenedicarboxylate) has been synthesized and characterized by X-ray crystallography. Compound 1 crystallizes in the orthorhombic space group Pcnb, with a = 8.764(2) , b = 17.687(2) , c = 19.475(1) , V = 3018.7(8) ³, Z = 4, R₁, (wR₂) for 2148 observed reflections of [1>2σ(I) was 0.0822 (0.2236). Compound 1 is interconnected to give a three-dimensional network through weak hydrogen-bonding interactions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.43-50
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• 2001

In order to analyze the dynamic motions of fish cage systems made of a frame and a netting under the conditions of waves and current, the hydraulic model experiment at towing tank and the numerical computation using boundary integral element method based on linear potential theory were carried out on a square and a circular type of fish cage, The computed and measured results for the dynamic motions of model fish cage systems showed that the heave and pitch motions were almost unaffected by the inclusion of nets, while the surge motions were very reduced by drag force acting on them. In addition, irregular wave-induced motions of fish cages included non-negligible 2nd order harmonic components at high frequency nearly twice the wave frequency. The reason why these motions were considered was due to resonance or structural components of frames being overflown and out of water during a wave cycle. It was found that circular type was more desirable structure in the open sea than square one only in the respect of dynamic motions due to waves and current. Further verifications were needed considering hydrodynamic forces, fatigue life, and structure analysis based on long term stochastic waves including frequency and time domain for the purpose of analyzing and designing fish cage systems.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.3
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• pp.216-222
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• 2010

The structural methods used to protect coastal erosion are usually very expensive in construction as well as in spending on maintaining the structures from damage. Those structures like embankments, breakwaters, jetties etc. are commonly constructed with concretes (rigid methods) to protect coastal erosion. But those rigid methods are not effective always, because the wave energy and impact force on the structures could not be effectively reduced by those methods. For avoiding sediment erosion on coastal areas by the way of reducing wave energy, a flexible breakwater is introduced which will reduce energy and protect coastline economically and environmentally. The flexible device is a combination of flexible wire nets and stack of rings made of used vehicle tires and soft blades on surfaces. This flexible wire net is placed in between two stacks of rings. The stack of rings is mainly used to hold the flexible wire nets and the flexible wire net is mainly used to reduce wave energy and helps to deposit sediments in coastal area. For a field experiment study, the above-mentioned flexible breakwater of coastal protection has been set up at the Shuang-Chun coastal area in Tainan County since June 10, 2009. The length of the flexible device is 50.0 meters and the height is 2.0 meters. The function of the device has been examined by Typhoon Linfa during June 19~22, 2009 and by Typhoon Morakot during August 6~10, 2009. The result shows that the flexible breakwater has effectively trapped sediments and let them deposit on coastal. The depth of sediment deposition around the device was about 0.5 to 0.8 meters.

• Journal of the Korean Vacuum Society
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• v.7 no.3
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• pp.248-254
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• 1998

DLC(Diamond-Like-Carbon) thin film, one of the solid state amorphous carbon films, has been deposited by the method of PECVD (Plasma Enhanced Chemical Vapor Deposition). The structural features have been characterized using both FT-IR Spectroscopy and Raman Scattering. The film is considered to consist of microcrystalline diamond domains and graphitelike carbon domains, which are interconnected by hydrogenated $sp^3$ tetrahedral carbons. This shows a good agreement with the results by I-Vmeasurements. In I-Vstudy, the sudden increase of current has been observed and this phenomenon is understood to be due to the tunneling effect between graphitelike domains. A characteristic feature related to the $\beta$-SiC has been identified in the study of Raman Scattering for the very thin film, which suggests that a buffer layer forms at the interface of the Si substrate and the carbon film.

• Korean Journal of Crystallography
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• v.15 no.1
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• pp.5-8
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• 2004

The hydrothermal reaction of copper(I) bromide (CuBr) and pyrazine ($C_4H_4N_2$, pyz) gave a 2-D corrdination polymer [CuBr(pyz)] (1). X-ray structure determination revealed that polymer 1 has a 2-D network based on rectangular grids, each of which has the dimensions of 4.0${\times}$5.7 ${\AA}$. Polymer 1 has channels along the b-axis.

• Korean Journal of Crystallography
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• v.13 no.2
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• pp.96-100
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• 2002

The title compound, (H/sub 3/NCH/sub 2/CH/sub 2/NH/sub 3/)HPO/sub 4/ (Ⅰ), has been synthesized by hydrothermal technique for the first time and its novel structure analyzed by X-ray single crystallography. The compound (Ⅰ) crystallizes in the monoclinic system, P2/sub 1//c space group with a＝10.209(1), b＝7.891(1), c＝ 8.039(1) (equation omitted), β＝ 92.138(9)°, V＝: 647.2(2) (equation omitted), Z＝4, R/sub 1/＝0.0295 and ωR/sub 2/＝0.0811 for 1141 independent reflections. The compound (Ⅰ) is interconnected to give a three-dimensional network through hydrogen-bonding interactions.