• Journal of Communications and Networks
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• 제8권2호
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• pp.234-240
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• 2006

We study the dynamic burst assembly based on traffic prediction and offset and delay differentiation in optical burst switching network. To improve existing burst assembly mechanism and build an adaptive flexible optical burst switching network, an approach called quality of service (QoS) based adaptive dynamic assembly (QADA) is proposed in this paper. QADA method takes into account current arrival traffic in prediction time adequately and performs adaptive dynamic assembly in limited burst assembly time (BAT) range. By the simulation of burst length error, the QADA method is proved better than the existing method and can achieve the small enough predictive error for real scenarios. Then the different dynamic ranges of BAT for four traffic classes are introduced to make delay differentiation. According to the limitation of BAT range, the burst assembly is classified into one-dimension limit and two-dimension limit. We draw a comparison between one-dimension and two-dimension limit with different prediction time under QoS based offset time and find that the one-dimensional approach offers better network performance, while the two-dimensional approach provides strict inter-class differentiation. Furthermore, the final simulation results in our network condition show that QADA can execute adaptive flexible burst assembly with dynamic BAT and achieve a latency reduction, delay fairness, and offset time QoS guarantee for different traffic classes.

• 대기
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• 제26권3호
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• pp.445-459
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• 2016

Air temperature deviation (ATD) is one of major indicators to represent spatial distribution of urban heat island (UHI), which is induced from the urbanization. The purpose of this study is to evaluate the accuracy of air temperature deviation about Climate Analysis Seoul (CAS) workbench, which had developed by National Institute Meteorological Science and TU Berlin. Comparison and correlation analysis for CAS ATD including meso-scale air temperature deviation, local-scale air temperature deviation, total air temperature deviation, surface heat flux deviation, cold air production deviation among meso-scale numerical modelling variable in 'Seoul Region', micro-scale numerical modelling in 'Detail Region', and CAS workbench variable using observation data in ground stations. Comparison between night time OBS ATD and CAS ATD show that have most close values. Most of observations ($dT_{max}$ and $dT_{min}$) have highly positive ($dT_{SHP}$, $dT_{CA}$, MD, TD, $f_{BS}$, $f_{US}$, $f_{WS}$, $h_B$) and negative ($f_{VS}$, $f_{TV}$, $h_V$, Z) correlations. However, CAS workbench needs further improvement of both observational framework and analytical framework to resolve the problems; (1) night time OBS ATD of has closer values in compare with at high rise mountain area and (2) correlations are very dependable to meteorological scale.

• Clinical and Experimental Reproductive Medicine
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• 제24권1호
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• pp.43-49
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• 1997

본 연구는 단위발생과 체외수정으로 생산된 돼지 난자의 발달양상과 inner cell mass(ICM) 그리고 trophectoderm (TE)의 세포배열을 조사하기 위하여 실시하였다. 단위발생은 ethanol 단독처리(haploid) 혹은 ethanol과 cytochalasin B을 공동처리(diploid)하였던바, 단위발생란은 체외수정란에 비하여 배반포까지의 발달이 저조하였지만, 단위발생에 있어서 ethanol과 cytochalasin B을 공동처리한 군이 ethanol 단독처리한 군보다 배반포까지 발달이 촉진되었다. 또한 단위발생란의 경우 total 세포수와 ICM 수에 있어서 체외수정란에 비하여 현저하게 감소되었지만, ethanol과 cytochalasin B을 공동처리한 단위발생란이 ethanol 처리된 단위발생란보다는 현저하게 높은 total 세포수와 ICM 수가 조사되었다. 이상의 결과로, 돼지의 착상전 배발달 양상과 ICM와 TE의 세포배열에 있어서 ploidy가 영향을 미친다는 것을 알수 있었다.

• 한국통신학회논문지
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• 제29권8B호
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• pp.721-729
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• 2004

본 논문에서는 광 버스트 스위칭 네트워크의 코어 노드에 그룹 스케줄링 알고리즘을 적용하여, 전산 모의실험을 통해 그 성능을 측정하였다. 성능 평가를 위해, 다채널 입출력 포트를 갖는 코어 노드에 대하여, 즉시 스케줄링 방식과 비교하였다. 그룹 스케줄링은 노드에 먼저 도착하는 버스트 헤더 패킷의 정보를 이용하여 일정한 시간 창에 스케줄링 될 버스트들을 스케줄링하기 때문에, 전산 모의실험 결과 그룹 스케줄링 방식이 즉시 스케줄링 방식보다 버스트 손실 확률과 채널 이용률이 모두 개선되었으며 부하의 증가에 따라 차이가 더욱 커졌다. 또한, 출력포트에 파장 변환기를 사용한 경우에 대해서도 성능을 측정하였다. 이 경우에는, 그룹 스케줄링 방식과 즉시 스케줄링 방식의 버스트 손실 확률과 채널 이용률 모두 부하 범위 0.1-0.9에서 서로 비슷하게 나타났으나. 파장 변환기의 사용 빈도는 즉시 스케줄링이 그룹 스케줄링보다 약 7배 이상으로 높아, 그룹 스케줄링 방식을 사용하면 보다 경제적인 노드 구조를 구현할 수 있음을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제23권6호
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• pp.864-871
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• 2013

The recombinant strain P. pastoris GS115-lccC was used to produce laccase with high activity. Factors influencing laccase expression, such as pH, methanol concentration, copper concentration, peptone concentration, shaker rotate speed, and medium volume were investigated. Under the optimal conditions, laccase activity reached 12,344 U/L on day 15. The recombinant enzyme was purified by precipitating and dialyzing to electrophoretic homogeneity, and was estimated to have a molecular mass of about 58 kDa. When guaiacol was the substrate, the laccase showed the highest activity at pH 5.0 and was stable when the pH was 4.5~6.0. The optimal temperature for the laccase to oxidize guaiacol was $60^{\circ}C$, but it was not stable at high temperature. The enzyme could remain stable at $30^{\circ}C$ for 5 days. The recombinant laccase was used to degrade chlorpyrifos in several laccase/mediator systems. Among three synthetic mediators (ABTS, HBT, VA) and three natural mediators (vanillin, 2,6-DMP, and guaiacol), vanillin showed the most enhancement on degradation of chlorpyrifos. Both laccase and vanillin were responsible for the degradation of chlorpyrifos. A higher dosage of vanillin may promote a higher level of degradation of chlorpyrifos, and the 2-step addition of vanillin led to 98% chlorpyrifos degradation. The degradation of chlorpyrifos was faster in the L/V system ($k_{obs}$ = 0.151) than that in the buffer solution ($k_{obs}$ = 0.028).

• Reproductive and Developmental Biology
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• 제35권2호
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• pp.175-183
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• 2011

The present study compared the developmental potential, telomerase activity and transcript levels of X-linked genes (ANT3, HPRT, MeCP2, RPS4X, XIAP, XIST and ZFX) in the bovine somatic cell nuclear transfer (SCNT) embryos derived from different age and cell cycle of female donor nucleus. In experiment 1, the fusion rate, cleavage rate to 2-cell stage, developmental rate to blastocyst stage, and the mean number of total and ICM cells was slightly increased in embryos cloned with fetal fibroblasts compared to those with adult fibroblasts, but there was no significantly (p<0.05) differences. Telomerase activity was also similar in blastocysts cloned with fetal and adult fibroblasts. Up-regulated RPS4X and down-regulated MeCP2, XIAP, and XIST transcript level were observed in blastocysts cloned with adult fibroblasts, compared to those with fetal fibroblasts. In experiment 2, the fusion rate, cleavage rate to 2-cell stage, developmental rate to blastocyst stage, and the mean number of total and ICM cells was significantly (p<0.05) increased in embryos cloned with fetal fibroblasts at early G1 phase of the cell cycle, compared to those of fetal fibroblasts at late G1 phase. DNMT1 transcript was observed to significantly (p<0.05) increased in the fetal fibroblasts at 3 hrs after trypsin treatment of confluent culture. Further, level of telomerase activity and transcribed X-linked genes was also significantly (p<0.05) higher in the early G1 SCNT blastocysts than those of late G1. The results imply that fetal fibroblasts at early G1 phase induces the enhanced developmental potential and up-regulated telomerase activity and X-linked gene, but aberrant transcript pattern of X-linked genes may be displayed in the SCNT embryos.

• 대한화학회지
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• 제32권6호
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• pp.528-535
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• 1988

이성분 혼합용매 속에서 $[Mo_2O_3(Ox)_2(OxH)_2(NCS)_2]$의 산소고리화 반응에 대한 속도론적 연구는 분광광도법으로 수행되었다. 이 때 온도는 $20^{\circ}C$ 에서 $40^{\circ}C$, 압력은 1bar에서 1500 bar로 변화시켰다. 관찰된 속도 상수는 수소이온 농도의 증가에 따라 증가하고 티오시안이온 농도의 증가에 따라서는 감소한다. 공용매의 유전상수가 증가할수록 더욱 안정한 중간체가 형성된다. 관찰된 속도상수는 $k_{obs}^{-1} = k^{-1} (1 + K^{-1}[H_2O]^{-1})로 주어진다. 모든 활성화파라미터는 양의 값이다. [Mo_2O_3(Ox)_2(OxH)_2(NCS)_2]$의 산소고리화 반응은 Id 메카니즘에 의해 진행된다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 특별 심포지엄 논문집
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• pp.53-62
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• 2007

Preliminary gas hydrate surveys were carried out From 2000 to 2004 in the East Sea. Research results showed the geophysical evidence of gas hydrate existence. In 2005, Gas Hydrate R&D Organization was established and 10 year gas hydrate development program was initiated. In the $1^{st}$ stage of the program from 2005 to 2007, 6,600 L-km 2-D seismic survey was conducted in the $1^{st}$ year 2005, and $400\;km^2$ 3D survey was conducted in the $2^{nd}$ year 2006. Acquired seismic data were processed and seismic section and 3D cube were produced. By geophysical interpretation and velocity analysis, prospective areas were mapped and candidate drilling sites were recommended. For the precise interpretation, velocity was analyzed using AVO method, and BSR signal was analyzed using deconvolution method. For the prospective area, OBS and high-resolution seismic surveys were conducted. This presentation shows the introduction and examples of the research results of the geophysical methods applied for the gas hydrate exploration in the East Sea.

• 대한화학회지
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• 제27권2호
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• pp.133-141
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• 1983

일련의 1-aryl-2-pyrrylideneaniline (3)을 합성하여 20% MeOH용액에서 산촉매에 의한 가수분해 반응을 속도론적으로 연구하였다. 화합물 3a-h의 가수분해 반응에 대한 치환기의 효과는 비록 적었지만 치환기가 전자끄는기 일수록 가수분해 반응속도는 증가하며 $log k_{obs}$를 Hammett ${\sigma}$상수에 대하여 도시한 결과 직선관계를 나타냄으로써 치환기가 pyrrole 화합물의 방향성에 상당한 관계를 갖고 있음을 알 수 있다. 또한 그 직선의 기울기로부터 구해낸 ${\rho}$값이 양의 값을 갖는 사실은 imine의 가수분해 반응 메카니즘고 일치하는 것으로, pH 4에서 8사이의 완충용액에서 imine의 가수분해 반응의 속도결정 단계는 양성자가 첨가된 imine에 물분자가 공격하는 것이고, 반면에 pH 8이상의 영역에서는 free imine에 물분자가 공격하는 것이 속도결정 단계가 된다. 이는 치환기가 반응속도에 미치는 영향과도 일치하는 값이다.

• 한국환경과학회지
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• 제26권10호
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• pp.1167-1180
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• 2017

Numerical Weather Prediction (NWP) models such as the Weather Research and Forecasting (WRF) model are essential for forecasting one-day-ahead solar irradiance. In order to evaluate the performance of the WRF in forecasting solar irradiance over the Korean Peninsula, we compared WRF prediction data from 2008 to 2010 corresponding to weather observation data (OBS) from the Korean Meteorological Administration (KMA). The WRF model showed poor performance at polluted regions such as Seoul and Suwon where the relative Root Mean Square Error (rRMSE) is over 30%. Predictions by the WRF model alone had a large amount of potential error because of the lack of actual aerosol radiative feedbacks. For the purpose of reducing this error induced by atmospheric particles, i.e., aerosols, the WRF model was coupled with the Community Multiscale Air Quality (CMAQ) model. The coupled system makes it possible to estimate the radiative feedbacks of aerosols on the solar irradiance. As a result, the solar irradiance estimated by the coupled system showed a strong dependence on both the aerosol spatial distributions and the associated optical properties. In the NF (No Feedback) case, which refers to the WRF-only stimulated system without aerosol feedbacks, the GHI was overestimated by $50-200W\;m^{-2}$ compared with OBS derived values at each site. In the YF (Yes Feedback) case, in contrast, which refers to the WRF-CMAQ two-way coupled system, the rRMSE was significantly improved by 3.1-3.7% at Suwon and Seoul where the Particulate Matter (PM) concentrations, specifically, those related to the $PM_{10}$ size fraction, were over $100{\mu}g\;m^{-3}$. Thus, the coupled system showed promise for acquiring more accurate solar irradiance forecasts.