• Journal of environmental and Sanitary engineering
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• v.10 no.1
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• pp.126-131
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• 1995

Chitinase, a potential pathogensis- related portein, was induced in the leaves of 30 day - old bean( phaseolus vulgaris ) plant with the treatment of 10 $\mu $ /mℓ ethylen for 30hrs. Chitinase was purified from the mature tissue of bean leaves( phaseolus vulgaris ) by ammonium sulfate precipitation followed by affinity chromatography on a regenerated chitin and sephadex G-75 chromatography. The purified chitinase gave a single band SDS- PAGE to be 32,000 Dalton. In order to elucidate the three- dimensional structure of chitinase and to shed light on the functional mechanism of this class of enzymes, the enzyme was tried to crystallize( Sitting Drop Method). Crystals grew at room temperature to their final size within two weeks(0.2mm $\times $0.2mm $\times $ 0.1 mm ), This enzyme are still continuing to crystallize for the study of X- ray.

• Proceedings of the Optical Society of Korea Conference
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• 2002.07a
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• pp.258-259
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• 2002

광회선 분배 시스템(OXC)은 전광통신망(Optical Transport Network)에서 광신호 간 연결을 원격으로 설정해 줄 수 있는 노드(Optical Network Element)이다. OXC는 다수의 입력/출력 링크를 가지며 하나의 입력/출력 링크에는 다수의 파장 다중된 광신호 채널이 존재한다. OXC는 하나의 입력 링크를 통하여 입력되는 다수의 파장 채널을 서로 다른 출력 링크로 연결해 주거나, 다수의 입력 링크로부터 입력되는 파장채널을 하나의 출력 링크로 연곁해 줄 수 있는 optical grooming 기능을 수행한다. 또한 자국에서 광신호를 Add/Drop할 수 있는 기능을 가질 수 있다. (중략)

• Journal of the Korean institute of surface engineering
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• v.35 no.3
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• pp.149-157
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• 2002

Spectral emissivity depends on the surface conditions of the materials. The mechanisms that affect the spectral emissivity in anodic oxide films on aluminum were investigated. The aluminum specimens were anodized in a sulfuric acid solution and the thickness of the resulting oxide film formed changed with the anodizing time. FT-IR spectrum analysis identified the anodic oxide film as boehmite ($Al_2$$O_3$.$H_2$O). Both the infrared emisivity and reflectivity of the anodized aluminum were affected by the structure of the anodic oxide film because Al-OH and Al-O-Al have a pronounced absorption band in the infrared region of the spectrum. The presence of an anodic oxide film on aluminum caused a rapid drop in the infrared reflectivity. An aluminum surface in the clean state had an emissivity of approximately 0.2. However, the infrared emissivity rapidly increased to 0.91 as the thickness of the anodic oxide film increased.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.71-75
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• 2005

For the damage tolerance improvement of conventional laminated composites, stitching process have been utilized for providing through-thickness reinforcements. 2D preforms were stacked with S-2 glass plain weave and S-2 glass MWK (Multi-axial Warp Knit) L type. 3D preforms were fabricated using the stitching process. All composite samples were fabricated by RTM (Resin Transfer Molding) process. To examine the damage resistance performance the low speed drop weight impact test has been carried out. For the assessment of damage after the impact loading, specimens were examined by scanning image. CAI (Compressive After Impact) tests were also conducted to evaluate residual compressive strength. Compared with 2D composites, the damage area of 3D composites was reduced by 20-30% and the CAI strength showed 5-10% improvement.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.895-898
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• 2008

The mobility of water in set yogurt during fermentation was studied using nuclear magnetic resonance (NMR) relaxometry. The spin-spin relaxation was analyzed using a 2-fraction model, resulting in 2 spin-spin relaxation time constants $T_{21}$ and $T_{22}$. Both $T_{21}$ and $T_{22}$ exhibited rapid changes between 2 and 4 hr of fermentation, coinciding with the drop in pH and the rise in lactic acid bacteria count. The spin-lattice relaxation time $T_1$ increased over the fermentation period. Both $T_1$ and $T_2$ showed an increase in the mobility of water upon gel formation during fermentation. Water redistribution within the gel matrix due to casein aggregation and structure forming may be responsible for the changes in mobility.

• Korean Journal of Organic Agriculture
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• v.6 no.2
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• pp.107-116
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• 1998

The result of application of the organic manure obtained from livestocks fed with BLCS in the altari radish under structure were as follow. The no. of leaves, leaf, root length, root width, and total weight of altari radish treated with dong of fowl(BLCS) were the highest in any other treatment, and cattle drop-ping (BLCS) was higher, also. The contents of total N, P2O5, K2O, CaO, MgO, and sugar content in the altari radish treated with dong of fowl(BLCS) were the highest, and the second was cattle dropping (BLCS). The contents of OM, P2O5, K, Ca, Mg, and CED of soil treated with microorganism were the highest in the cattle dropping (BLCS) in any other plots, however. In general, effect of cattle manure fed with BLCS on the altari radish yield and mi-crobial activity were higher than cattle manure did not feed BLCS.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.196-201
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• 2006

In general, the vertical vibration problems for strength of members and serviceability of building structures are not considered in structural design process, but the prediction of the vertical vibration is very important and essential to structural design process. This study aims to investigate the characteristics of vertical vibration in terms of the transfer of horizontal directions on the rahmen building structures and the shear wall building structures. In order to examine the characteristics of vertical vibration, the modal test and the heel-drop excitation experiments were conducted several times on the two type building structures. The results from the experiments are analyzed and compared with the results. The results of this study suggest that the characteristics of vortical vibration transfer in horizontal way are effected from the fundamental frequency of the slabs and excitation forces and are effected the shear wall on the path of the vibration transfer.

• Nuclear Engineering and Technology
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• v.31 no.3
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• pp.314-327
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• 1999

A subchannel analysis code MATRA applicable to PWRs and ALWRs has been developed to be run on an IBM PC or HP WS based on the existing CDC CYBER mainframe version of COBRA-Rf-1. This MATRA code is a thermal-hydraulic analysis code based on the subchannel approach for calculating the enthalpy and How distribution in fuel assemblies and reactor cores for both steady-state and transient conditions. HATRA has been provided with an improved structure, various functions, and models to give more convenient user environment and to enhance the code accuracy. Among them, the pressure drop model has been improved to be applied to non-square-lattice rod arrays, and the models for the lateral transport between adjacent subchannels have been improved to enhance the accuracy in predicting two-phase flow phenomena. The predictions of MATRA were compared with the experimental data on the flow and enthalpy distribution in some sample rod-bundle cases to evaluate the performance of MATRA. All the results revealed that the predictions of MATRA were better than those of COBRA-IV-I.

• Proceedings of the KIPE Conference
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• 2007.11a
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• pp.218-220
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• 2007

A new 3-phase voltage disturbance generator is proposed. The voltage drop of the conventional generator in normal mode can be reduced significantly. The output voltage of the proposed generator is constant in normal mode and the efficiency of the series transformer is improved. The proposed generator has good feature of simple structure, cost effective implementation, high reliability, high efficiency, and easy control. The usefulness of the scheme is verified through simulation and experiments.

• Journal of the Korean Society of Safety
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• v.13 no.4
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• pp.96-101
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• 1998

J-R curve tests were performed on 1T compact specimens of SA516 Gr. 70 carbon steels under reverse cyclic loading. A Direct-Current Potential Drop (DCPD) method, one of the nondestructive techniques to detect flaw of structure, is being increasingly used for monitoring crack initiation and stable crack growth in typical fracture mechanics specimens for J-R testing. In many aspects this method is simpler than the unloading compliance method. The objective of this paper is to evaluate the J-R Curve according to the crack length measurement techniques under reverse cyclic loading. In order to prove the reliability and repeatability of the DCPD method, the crack length measured by using DCPD method was compared to one determined from unloading compliance. Consequently, this DCPD method correlated well with J-R curves and crack extension measurements determined from unloading compliance method.