• 대한화학회지
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• 제39권5호
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• pp.421-426
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• 1995

2-Hydroxyethyl methacrylate(HEMA)와 ethylene glycol dimethacrylate(EDGMA)로부터 수용액중에서 친수성 3차원 메타아크릴레이트 고분자 망상의 수화겔을 제조하여 NMR 분석법에 의해 그 친수성 메타아크릴레이트와 물 사이의 상호작용에 대하여 연구하였다. 적은 양의 물을 함유하고 있는 수화겔의 스핀-격자 이완시간$(T_1)$을 측정한 결과 물 양성자 주위의 다른 두 환경에 따른 $T_{1a}$와 $T_{2b}$가 나타났다. Poly(2-hydrocyethyl methacrylate)[p(HEMA)]-$(10{\%}\; H_2O)$ 수화겔에 대한 $T_{1a}$와 $T_{1b}$가 각각 $16.4{\times}10^{-3}\; sec$와 $58.2{\times}10^{-3}\;sec$이고, 가교된 EGDMA-p(HEMA)- $(10{\%}\; H_2O)$ 수화겔에 대한 $T_{1a}$와 $T_{2b}$가 각각 $13.2{\times}10^{-3}\; sec$와 $23.1{\times}10^{-3}\; sec$이었다. 또한 수화겔들에 대해 스핀-스핀 이완시간$(T_2)$를 측정한 결과 $p(HEMA)-(H_2O)_n$ 및 가교된 $EDGMA-p(HEMA)-(H_2O)_n$의 계에 $(T_2)$값은 물 함량이 증가함에 따라 증가하였다. $(T_2)$값들은 $(T_1)$의 값들보다 약 10배 작게 나타나고 스핀이완원리와 일치하였다.

• 한국산림과학회지
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• 제88권4호
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• pp.477-484
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• 1999

본 연구는 삼림(森林)내에 개설(開設)된 임도(林道)가 부유사유출(浮遊砂流出)에 미치는 영향을 검토하기 위한 기초적 연구로서 수행되었다. 부유사유출(浮遊砂流出)의 관측(觀測)은 산지유역(山地流域)으로서 임도(林道)의 영향을 받지 않는 관측점(觀測点) A와 B, 그리고, 그 합유점(合流點) 하류(下流)에 임도(林道)로부터의 토사유출(土砂流出)의 영향을 받는 관측점(觀測点) C에서 실시하였다. 부유사농도(浮遊砂濃度)의 경시적(經時的) 변화(變化)를 검토한 결과, 강우(降雨)중 임도(林道)의 영향에 따른 부유사농도(浮遊砂濃度)의 증가를 확인할 수 있었으며, 각 관측점(觀測点)의 유역특성(流域特性)에 따라 최대 부유사농도(浮遊砂濃度)는 피크유량(流量)을 선행(先行) 또는 동시(同時)에 나타났다. 이것은 비탈면에 불안정하게 정체하고 있었던 부유사(浮遊砂)가 강한 강우강도(降雨强度)의 영향으로 계류수(溪流水)에 빠르게 유출(流出)하는 시간적 차이에 기인하는 것으로 생각된다. 각 관측점(觀測点)의 부유사량(浮遊砂量)은 강우인자(降雨因子) 및 관측기간에 따라 차이는 있지만, 임도(林道)의 영향을 받는 관측점(觀測点) C가 임도(林道)의 영향을 받지 않는 관측점(觀測点) A 및 B보다 최대 4배 이상 많게 유출(流出)하였다. 단위면적(單位面積)당 부유사량(浮遊砂量)의 경우, 강우인자(降雨因子)의 영향을 가장 크게 받았던 9월 18일~19일(강우량(降雨量) 57.0mm)의 관측결과, 임도(林道)의 영향을 받는 관측점(觀測点) C는 4.179g/sec/ha, 임도(林道)의 영향을 받지 않는 관측점(觀測点) A 및 B는 각각 0.343g/sec/ha과 0.147g/sec/ha이었으며, 관측점(觀測点) C에서 관측점(觀測点) A, B보다 12배, 28배 증가하였다.

• 한국수산과학회지
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• 제43권5호
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• pp.551-556
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• 2010

The large jellyfish Nemopilema nomurai causes serious damage to fisheries, particularly around the seas of Korea and Japan. Decreasing this damage requires knowledge of the distribution and abundance of jellyfish. Acoustic technology using quantitative echosounders is one method of studying the distribution and abundance of jellyfish. Such methods are commonly used worldwide because they have the advantage of providing substantial information about all water layers in a wide area in a short time. However, in order to conduct an acoustic survey, the acoustic characteristics of the target organism must be known. These can be altered by a number of factors, including pulsation, swimming angle, frequency and size. Accordingly, this study determined the variation in target strength according to pulsation of N. nomurai. Data were analyzed for two jellyfish with bell diameters in air of (a) was 32.0 and (b) 25.0 cm. The pulsation cycle of jellyfish (a) was 1.5~2.0 sec and the target strength (TS) cycle was 1.0~2.5 sec, while jellyfish (b) had a pulsation cycle of 1.0~1.5 sec and TS cycle of 1.0~3.0 sec. The variation width of the TS with the change in pulsation was 7.8 dB (-72.4~-64.6 dB) for jellyfish (a) and 10.3 dB (-71.6~-61.3 dB) for jellyfish (b). The variation in bell diameter was about 0.28 and 0.35, respectively. These results confirmed that the variation in bell diameter caused by pulsation is closely related to the variation in TS.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 추계학술대회
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• pp.283-288
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• 2003

The object of this study is to investigate a fracture characteristics of static tensile test as a function of acoustic emission according to the fiber orientation $\theta=0^{\circ}C$ in carbon/epoxy composites, CFRP. On tensile loading, it was recognized that the fracture characteristics of CFRP in a unidirectional composites. Using the results of the AE analysis(a=2mm), it was found that the amplitude distributions of AE signals corresponding the matrix cracking, fiber debonding or delamination, and fiber breaking are 55~70dB(<200sec), 100dB(200~600sec), and 80dB(>600sec).

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.110-116
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• 1998

몇 가지 그람양성 세균에서 secY 유전자가 함유된 operon의 구성이 rplO(L15)-secY-adk라는 결과를 토대로 L15와 adk 유전자일부를 primer로 제작하여 Streptomyces lividans TK24에서 secY 유전자가 함유된 1.8kb 단편을 PCR로 증폭하여 얻은 후 secY 유전자를 cloning하였다. 전 단편을 sequencing하여 추론한 아미노산으로 상동성을 조사해 본 결과 Escherichia coli, Bacillus subtilis, Micrococcus luteus, Bacillus licheniformis, Staphylococcus carnosus, Brevibacterium flavum, Streptomyces scabies의 SecY와 각각 46%, 43%, 57%, 44%, 42%, 56%, 90%의 유사성을 보이는 것으로 나타났으며 SecY의 소수성 profile 또한 서로 유사하고 10개의 membrane spanning segment를 동일하게 가지는 것으로 나타났다. 유전자 구조도 다른 그람양성균에서와 같이 L15-SecY-Adk순 이였으며 secY 유전자의 종결코돈과 adk 유전자의 개시코돈이 한 염기를 공유하는 상태의 translational coupling 구조를 하고 있었다. 이와 같이 단백질분비에 관여하는 유전자와 ribosome 구성요소, 그리고 ATP 합성에 관여하는 요소는 세포성장에 상호 연관 작용이 있는 것으로 사료된다.

• 한국미생물·생명공학회지
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• 제23권6호
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• pp.678-686
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• 1995

SecY is a central component of the protein export machinery that mediate the translocation of secretory proteins across the plasma membrane of Escherichia coli. In order to study the mechanism of protein secretion in Streptomyces, we have done cloning and sequencing of the Streptomyces coelicolor secY gene by using polymerase chain reaction method. The nucleotide sequence of the gene for SecY from S. coelicolor showed over 58% identity to that of M. luteus. The deduced amino acid sequences were highly homologous to those of other known SecY polypeptides, all having the potential to form 10 transmembrane segments, and especially second, fifth, and tenth segments were particularly conserved, sharing greater than 75% identity with W. lute s SecY. We propose that the conserved membrane-spanning segments actively participate in protein export. In B. subtilis and E. coli, the secY gene is a part of the spc operon, is preceded by the gene coding for ribosomal protein L15, and is likety coupled transcriptionally and translationally to the upstream L15 gene. In the other hand, secY gene of S. coelicolor and M. luteus have its own promoter region, are coupled translationally with adk gene and pr sented in adk operon.

• 대한교통학회지
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• 제8권2호
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• pp.43-54
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• 1990

Six Levels of Service are defined for each type of facility for which analysis procedures as available. They are given letter designations, from A to F with Level of Service A representing the best operating conditions and Level of Service F the worst. Yet the appropriate criteria by vehicle delay model in our situations are not formed. Therefore, The objective of this study is to form the criterion of by average approach delay based on the criterion of V/C ratio. Level-of-Service criterion of this study by TRANSYT-7F Delay Model is as follows. A:${\leq}35.5$ sec, B:${\leq}41$ sec, C:${\leq}48$ sec, D:${\leq}56.5$ sec, E:${\leq}66.5$ sec, F:>66.5 sec.

• 대한물리치료과학회지
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• 제11권1호
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• pp.14-19
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• 2004

Objective : This study obtained normative values for variable parameters of lumbar function with the isoinertial triaxial dynamometer in patients with chronic low back pain. Subjects and Methods : 30 patients(male 15, female 15) with chronic low back pain in this study. Variable parameters that were measured with the Isostation B-200 were lumbar range of motion, isometric maximum torques, and maximum velocities in three axis. Results : In patient male group mean R.O.M. was $82.9{\pm}12.5$ degrees in lumbar rotation, $76.5{\pm}17.1$ degrees in lumbar flexion/extension, and $64.3{\pm}14.5$ degrees in lumbar lateral flexion. In patient female group mean R.O.M. was $78.4{\pm}18.5$ degrees in lumbar rotation, $71.7{\pm}20.4$ degrees in lumbar flexion/extension, and $63.2{\pm}14.4$ degrees in lumbar lateral flexion. In patient male group mean isometric maximum torques was $64.7{\pm}23.8ft-lbs$ in lumbar rotation, $81.1{\pm}42.0ft-lbs$ in lumbar flexion, $122.2{\pm}43.6ft-lbs$ in lumbar extension, and $101.0{\pm}37.0ft-lbs$ in lumbar lateral flexion. In patient female group mean isometric maximum torques was $41.9{\pm}9.2ft-lbs$ in lumbar rotation, $49.9{\pm}23.9ft-lbs$ in lumbar flexion, $90.1{\pm}26.8ft-lbs$ in lumbar extension, and $62.0{\pm}16.7ft-lbs$ in lumbar lateral flexion. In patient male group mean maximum velocity of isoinertial exercise with low (25%) resistance was $102.4{\pm}28.8deg/sec$ in lumbar rotation, $108.9{\pm}32.2deg/sec$ in lumbar flexion/extension, and $103.5{\pm}30.4deg/sec$ in lumbar lateral flexion. In patient female group mean maximum velocity of isoinertial exercise with low (25%) resistance was $84.1{\pm}24.4deg/sec$ in lumbar rotation, $93.2{\pm}32.9deg/sec$ in lumbar flexion/extension, and $98.5{\pm}33.7deg/sec$ in lumbar lateral flexion. In patient male group mean maximum velocity of isoinertial exercise with high (50%) resistance was $74.0{\pm}20.9deg/sec$ in lumbar rotation, $98.7{\pm}32.8deg/sec$ in lumbar flexion/extension, and $85.0{\pm}25.8deg/sec$ in lumbar lateral flexion. In patient female group mean maximum velocity of isoinertial exercise with high (50%) resistance was $67.3{\pm}26.4deg/sec$ in lumbar rotation, $82.5{\pm}31.0deg/sec$ in lumbar flexion/extension, and $79.7{\pm}23.9deg/sec$ in lumbar lateral flexion. Conclusion : Maximum isoinertial velocities were more reliable and more significant than isometric maximum torque for the objective assessment of chronic low hack pain.

• 미생물과산업
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• 제17권1호
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• pp.10-18
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• 1991

A phylogenetic comparison of homologous protein can often supplement genetic and biochemical analysis by revealing conserved structures that are critical for function(Waugh et al., 1989). I therefore isolated a secY homologue from B. subtilis, a gram positive bacterium evolutionary distant from E. coli. The comparison and interplay between these two bacterial systems should contribute greatly to our understanding of the functions and interactions within systems evolved for protein translocation in both prokaryotic and eukaryotic organisms.

• Food Science and Biotechnology
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• 제16권6호
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• pp.1082-1084
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• 2007

Ultra-high temperature (UHT) processed full fat milk inoculated with Escherichia coli, Pseudomonas fluorescens, and Bacillus stearothermophilus was exposed to 30-60 kV/cm square wave pulsed electric field (PEF) with $1\;{\mu}sec$ pulse width, and $26-210\;{\mu}sec$ treatment time in a continuous PEF treatment system. Eight log reduction was obtained for E. coli and P. fluorescens and 3 logs reduced for B. stearothermophilus under PEF treatment conditions of $210\;{\mu}sec$ treatment time, 60 kV/cm pulse intensity at $50^{\circ}$. There was no significant change in pH and titration acidity of milk after PEF treatment. The electrical energy required to achieve 8 log reduction for E. coli and P. fluorescens was estimated to be about 0.74 kJ/L.