• Title/Summary/Keyword: Km value

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Study for Safety on the Curve in the High-speed Railway Track (고속철도 궤도의 곡선부 주행안전성 평가)

  • Seo Sa-Bum;Lee Dong-Ho;Koo Bong-Kue
    • Journal of the Korean Society for Railway
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    • v.8 no.4
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    • pp.354-360
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    • 2005
  • The railway track and the substructures constructed in the field test section of Kyongbu High Speed Line are the structures for HSL, for the first time designed and constructed by domestic technical group. It is very important to verify the local design criteria and specifications for these structures and also to assure the recordings for vibration or deflection produced on the essential parts of the structures. The study to verify the high-speed railway track performance and to ensure the run in safety on the track in curved section during the KTX run. Finally, the conclusion are drawn as follows. The measuring values of the deflection effort of the rail and displacement for verifying the track performance in the field test section of Kyoungbu HSL satisfy the criteria of the foreign countries (Japan and Germany). The measured value for the wheel load and the presumed value show the consistent tendency. The wheel loads of the exterior and interior of the rails at the speed superior to 300km/h are measured same. Finally, the comparison between the theoretical value presented during the verification of the derailment to evaluate the safety of the train run at the time of the detailed design of the track and the measured value in the field shows that the correct design of track structure was applied.

Bias Correction of RCP-based Future Extreme Precipitation using a Quantile Mapping Method ; for 20-Weather Stations of South Korea (분위사상법을 이용한 RCP 기반 미래 극한강수량 편의보정 ; 우리나라 20개 관측소를 대상으로)

  • Park, Jihoon;Kang, Moon Seong;Song, Inhong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.54 no.6
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    • pp.133-142
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    • 2012
  • The objective of this study was to correct the bias of the Representative Concentration Pathways (RCP)-based future precipitation data using a quantile mapping method. This method was adopted to correct extreme values because it was designed to adjust simulated data using probability distribution function. The Generalized Extreme Value (GEV) distribution was used to fit distribution for precipitation data obtained from the Korea Meteorological Administration (KMA). The resolutions of precipitation data was 12.5 km in space and 3-hour in time. As the results of bias correction over the past 30 years (1976~2005), the annual precipitation was increased 16.3 % overall. And the results for 90 years (divided into 2011~2040, 2041~2070, 2071~2100) were that the future annual precipitation were increased 8.8 %, 9.6 %, 11.3 % respectively. It also had stronger correction effects on high value than low value. It was concluded that a quantile mapping appeared a good method of correcting extreme value.

Mechanical Degradation of Polymers in Dilute Solution (III). The Influence of the Mixed Solvents (稀薄溶液에서의 Polymer의 機械的 切斷 (제3보). 混合溶媒의 영향)

  • Yeong Moo Won
    • Journal of the Korean Chemical Society
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    • v.17 no.3
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    • pp.207-212
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    • 1973
  • The mechanical degradation of poly (-vinylacetate) in several mixed solvents (dioxane-n-butanol, dioxane-sec-butanol, dioxane-ethyleneglycol, dioxane-kerosene.) was studied using the capillary flow method. The velocity constant of scission reaction (k) and the limited degree of polymerization (g) were compared at the same value of [${\eta}$], which is considered as the parameter of molecular dimension of polymers in solution. As result, (k) did not change much, even if the species and the volume fraction of poor (non-) solvents changed, while the value of (g) changed according to the species of poor solvents and the value of [${\eta}$]. From the facts described above, It follows that the limited degree of polymerization (g) were affected by the composition and distribution of mixed solvent molecules around the polymer chain, and the value of $\alpha$ (at [${\eta}$] = $KM^a$) in the polymer solution.

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Review on Human Comfort Criteria in Tall Buildings (초고층건축물의 수평진동사용성 평가 기준의 재고)

  • Cho, Kang-Pyo;Jeong, Seung-Hwan;Cho, Gi-Sung;Km, Mu-Hwan
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.410-415
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    • 2008
  • This paper presents review on human comfort criteria in major codes and standards for tall buildings. In general, human comfort criteria of tall buildings have been used by magnitude of wind-induced acceleration response. Two different indexes in determination of the magnitude have been used: the peak value which occurs during a period of time and the rms value averaged over this same period. These distinctive acceleration indexes are discussed in detail and each criterion is reviewed and compared. The distinctions arisen because of the different wave forms, or acceleration signatures are addressed. It is described that which index of acceleration should be adopted in establishment of Korean human comfort criteria. In addition, some arguments from a technical standpoint that favor the use of each index are presented.

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A safety assessment by Risk Analysis Method on wheelchair occupant in side impact (측방충돌시 휠체어 탑승자의 위험도 분석에 의한 안전성평가)

  • 김성민;김성재;강태건;전병호;김경훈;문무성;홍정화
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.10a
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    • pp.16-16
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    • 2003
  • In this study, for a safety assessment of wheelchair occupant in side impact, we used a dynamic sled impact test results. The test was carried out total 6 times and impact speed was 13g$\pm$0.43/28km/h$\pm$0.95, By using EURO SID-1 dummy, head performance criteria(HPC), abdominal peak force, etc. were measured. We evaluated wheelchair occupant safety by motion criteria(MC) which was measured by head, trunk and side deformation change of wheelchair and Head & Neck injury criteria(HNI) measured by using head and neck deformation angle and time relation. When we assumed that the maximum injury value in side impact was 100%, the results of motion criteria(MC) of wheelchair occupant were max 80.3, mim 32.3 and average 60.3%, Head & Neck injury criteria(HNI) value were max 118.4, min 14.5 and average 59.7%.

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Novel $Ca^{2+}$-ATPase Found in the Human Milk Membrane Fraction

  • Cho, Jin-Kook;Kanno, Choemon
    • 한국유가공학회:학술대회논문집
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    • 1997.05a
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    • pp.23-34
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    • 1997
  • Calcium-stimulated ATPase ($Ca^{2+}$-ATPase) which has optimal pH value at 7.0 was found in the membrane fraction of human milk, and its enzymatic properties were studied. The purified $Ca^{2+}$-ATPase required 0.45 mM Ca ion for maximal activity. Among the nucleosides, $Ca^{2+}$-ATPase showed a higher substrate specificity to ATP and UTP than to CTP and GTP. $Ca^{2+}$-ATPase had apparent Km value of 0.065, and V max of 7.63 mol ATP hydrolyzed/mg pro-tein per min, respectively. $Ca^{2+}$-ATPase was potently inhibited by lanthanide, vanadate, and p-chloromercuribenzoate, and inactivated by EDTA, and CDTA and EGTA, but were unaffected by N-ethylmaleimide, $NaN_3$, ouabain, or oligomycin, and was completely inactivated by heating at $60^{\circ}C$ for 10 min. This enzyme activity was concentrated in the membrane fraction of the cream and skim milk membrane, but not founded in bovine milk.

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Estimation of Insolation over the Oceans around Korean Peninsula Using Satellite Data

  • Park, Kyung-Won;Kim, Young-seup;Sang, Chung-Hyo
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.227-230
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    • 1999
  • Surface solar radiation over the sea is estimated using Visible and Infrared Spin Scan Radiometer data onbord Geostationary Meteorological Satellite(GMS) 5 for January, 1997 to December 1997 in clear and cloudy conditions. The hourly insolation is estimated with a spatial resolution of 5$\times$ 5 km grid. The island pyranometer belonging to the Japan Meteorological Agency is used for validation of the estimated insolation. It is shown that the estimated hourly insolation has RMSE(root mean square) error of 104 W/$m^2$. The variability of the hourly solar radiation was investigated on 3 areas over seas around Korean Peninsula. The solar radiation of East Sea is similar to Yellow Sea. The maximum value of solar radiation is on June of year. The maximum value in south sea is on August because weather is poor by low pressure and front in June

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Characteristics of Fungal Protease Produced by Mucor racemosus f. racemosus from Korean Traditional Meju (재래식 메주로부터 분리한 Mucor racemosus f. racemosus PDA 103이 생산하는 Fungal Protease 특성)

  • 임성일;유진영
    • Microbiology and Biotechnology Letters
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    • v.27 no.6
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    • pp.466-470
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    • 1999
  • Protease production and its characteristics were investigated with Mucor racemosus f. racemosus PDA 103 which was isolated from Korean traditional meju. Optimum culture conditions of the strain for the production of the protease in basic medium[bean(Baektae):H2O=1:1(w/v)] were as follows: pH 6, 3$0^{\circ}C$ and 72hrs. Optimum pH and temperature for the enzyme activity of the protease produced by Mucor racemosus f. racemosus were pH 5 and 5$0^{\circ}C$, respectively. The enzyme was relatively stable a pH2.0~5.0 and at temperature below 4$0^{\circ}C$. Phenylmethane-sulfonyl fluoride and Ag+ inhibited the enzyme activity. This indicates that the enzyme is serine protease. Km value was 0.9$\times$10-4M and Vmax value was 5.93$\mu\textrm{g}$/min. This enzyme hydrolyzed casein more rapidly than bovine albumin.

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Immobilization of Urease on Chitosan Matrix (Chitosan Matrix에 Urease의 고정화(固定化))

  • Lee, Chi-Young;Kim, Sung-Ho
    • Journal of Pharmaceutical Investigation
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    • v.15 no.3
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    • pp.93-99
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    • 1985
  • For the effective immobilization of urease on chitosan matrix with glutaraldehyde, optimal activation methods were studied, and its enzymatic properties was investigated. In the stability of enzyme. the retained activity of the native urease was 55% after it was soaked af pH 7 for 10 hrs., while the retained activity of immobilized one was about 62% after soaked at pH 6.5-8.5 for the same time. After heat treatment at $60^{\circ}C$ for 10 hrs., the native urease lost the most of its activity, while immobilized urease retained 54% of its activity by the same treatment. The retained activity of immobilized urease did not decrease nearly when it was stored at room temperature for 25 days. From Linweaver-Burk plots, the $V_{max}$ value of native urease was $66{\mu}M/l$ and that of immobilized urease was $41{\mu}M/l$, while Km value 40mM/l for both enzymes was unaltered.

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KOMPSAT EOC Grid Reference System

  • Kim, Youn-Soo;Kim, Yong-Seung;Benton, William
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.349-354
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    • 1998
  • The grid reference system (GRS) has been useful for identifying the geographical location of satellite images. In this study we derive a GRS for the KOMPSAT Electro-Optical Camera (EOC) images. The derivation substantially follows the way that SPOT defines for its GRS, but incorporates the KOMPSAT orbital characteristics. The KOMPSAT EOC GRS (KEGRS) is designed to be a (K,J) coordinate system. The K coordinate parallel to the KOMPSAT ground track denotes the relative longitudinal position and the J coordinate represents the relative latitudinal position. The numbering of K begins with the prime meridian of K=1 with K increasing eastward, and the numbering of J uses a fixed value of J=500 at all center points on the equator with J increasing northward. The lateral and vertical intervals of grids are determined to be 12.5 km about at the 38$^{\circ}$ latitude to allow some margins for the value-added processing. The above design factors are being implemented in a satellite programming module of the KOMPSAT Receiving and Processing System (KRPS) to facilitate the EOC data collection planning over the Korean peninsula.

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