• 한국지능시스템학회논문지
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• 제16권1호
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• pp.94-100
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• 2006

인터넷을 바탕으로 하는 컴퓨팅 패러다임의 변환은 인터넷에서 디지털 정보 교환의 표준으로 확고한 자리를 굳힌 XML의 사용을 가속화시키고 있다. 이로 인해 XML 데이터의 양이 기하급수적으로 증가하고 보다 효율적으로 XML 데이터를 저장하고 질의하기 위한 연구가 활발히 진행되고 있다. 본 논문에서는 대용량의 데이터 중심 XML를 효과적으로 관리하기 위한 방안으로 그래프 중심의 색인 방법을 연구, 제안한다. 논문에서 제안한 XML 색인은 XML 데이터와 XML 구조 정보를 크게 3개의 구성 성분으로 표현한 후, 메인 메모리 자료구조로 표현된 각 그래프들을 노드 아이디를 키로 사용하여 B+트리에 각 노드를 사상하고 B+트리를 디스크에 저장하여 이들 색인 모델에 대해 지속성을 부여하였다. 본 논문에서 제안한 색인 방법을 통해 XML 데이터의 크기에 따라 질의 처리시간이 선형적으로 증가하는 결과를 얻을 수 있었다.

• 방송공학회논문지
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• 제20권3호
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• pp.440-448
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• 2015

논문에서는 지능형 차량에 적용하기 위해 보행자의 의도를 분석하여 보행자와의 사고를 미연에 방지하는 시스템을 제안한다. 제안하는 시스템은 블랙박스 영상으로부터 실시간으로 보행자를 검출하고, 소실점을 바탕으로 한 보행자의 상대 위치와 옵티컬 플로우를 이용한 움직임 방향 정보를 추출한다. 이러한 보행자의 정보와 차량의 현재 속도에 기반한 차량 정지 거리를 이용하여 보행자와의 충돌 위험도를 파악하는 퍼지 로직을 구현하였다. 최종적으로 퍼지 로직의 출력 정보인 충돌 위험도에 따라 운전자에게 경고를 주도록 하였다. 마지막으로 실제 주행 영상을 이용하여 제안된 시스템의 성능과 한계점을 분석하였다.

• BMB Reports
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• 제41권4호
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• pp.338-343
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• 2008

Dehydrins (DHNs) compose a family of intrinsically unstructured proteins that have high water solubility and accumulate during late seed development at low temperature or in water-deficit conditions. They are believed to play a protective role in freezing and drought-tolerance in plants. A full-length cDNA encoding DHN (designated as ClDhn) was isolated from an oriental medicinal plant Codonopsis lanceolata, which has been used widely in Asia for its anticancer and anti-inflammatory properties. The full-length cDNA of ClDhn was 813 bp and contained a 477 bp open reading frame (ORF) encoding a polypeptide of 159 amino acids. Deduced ClDhn protein had high similarities with other plant DHNs. RT-PCR analysis showed that different abiotic stresses such as salt, wounding, chilling and light, triggered a significant induction of ClDhn at different time points within 4-48 hrs post-treatment. This study revealed that ClDhn assisted C. lanceolata in becoming resistant to dehydration.

• Journal of Magnetics
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• 제17권1호
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• pp.27-32
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• 2012

Transcranial magnetic stimulation requires an electric field composed of dozens of V/m to achieve stimulation. The stimulation system is composed of a stimulation coil to form the electric field by charging and discharging a capacitor in order to save energy, thus requiring high-pressure kV. In particular, it is charged and discharged in capacitor to discharge through stimulation coil within a short period of time (hundreds of seconds) to generate current of numerous kA. A pulse-type magnetic field is formed, and eddy currents within the human body are triggered to achieve stimulation. Numerous pulse forms must be generated to initiate eddy currents for stimulating nerves. This study achieved high internal pressure, a high number of repetitions, and rapid switching of elements, and it implemented numerous control techniques via introduction of the half-bridge parallel load method. In addition it applied a quick, accurate, high-efficiency charge/discharge method for transcranial magnetic stimulation to substitute an inexpensive, readily available, commercial frequency condenser for a previously used, expensive, high-frequency condenser. Furthermore, the pulse repetition rate was altered to control energy density, and grafts compact, one-chip processor with simulation to stably control circuit motion and conduct research on motion and output characteristics.

• 영어어문교육
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• 제17권4호
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• pp.357-373
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• 2011

There have been great controversies over making English as an official language in Korea. They have been triggered since some scholars published books and articles claiming that officialization of English is the best option for Korean people who spend significant amount of their life time to learn English. Those who are happy about the idea believe that officialization of English will be a good help for Korean people to gain a high degree of English proficiency, while others worry about possible negative impact on Korean language and culture. There are more diverse views and opinions on this issue. The distance between pros and cons about officialization of English doesn't seem to be negotiated. This study has been conducted not for finding the solution to the controversies. It is for understanding how those whose successful career and high living quality depend on gaining high command of English feel about acknowledging English as an official language of Korea. The results show that overall ideas on the officialization of English of research subjects are similar with those of scholars in academia. Around two third of total number of the research subjects expressed their criticism against the idea. One interesting thing is that all of the subjects, regardless their positions, think that there are serious problems in English education policy and system in Korea.

• Biomolecules & Therapeutics
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• 제15권4호
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• pp.212-217
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• 2007

In atrial myocytes, lacking t-tubules, $Ca^{2+}$ current ($I_{Ca}$)-initiated $Ca^{2+}$ release at the peripheral junctional sites propagates into the interior of the cell by diffusion of $Ca^{2+}$. We have previously reported that time of activation of the central sites is independent of $I_{Ca}$. In the present study we have probed the effects of Bay K 8644 on $Ca^{2+}$ propagation wave to the center of the myocyte using rapid 2-D confocal $Ca^{2+}$ imaging in the rat atrial myocytes. Enhancement of $I_{Ca}$ by Bay K 8644 accelerated the rate of peripheral $Ca^{2+}$ release, but did not affect the speed of propagation of central release. In contrast, enhancement of $I_{Ca}$ by intracellular cAMP reduced the magnitude of peripheral and central $Ca^{2+}$ transients, but significantly accelerated the speed of central $Ca^{2+}$ release. Our data suggest that the speed of central $Ca^{2+}$ propagation triggered by $I_{Ca}$ is not regulated by the magnitude of either $I_{Ca}$ or local cytosolic $Ca^{2+}$ releases.

• 천문학회보
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• 제35권2호
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• pp.34.1-34.1
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• 2010

Studies suggest that activities in luminous AGNs, residing mostly in early-type galaxies, are triggered by merging. However, the observational evidence for the connection between mergers and AGN activity is not clear yet because tracer of the past merging activities such as tidal tail, shell are often too faint. To see if we can reveal the merging features with a small telescope, we observed an AGN, MARK 478, at z=0.077 with long exposure time (7550 seconds) in V filter at Maidanak observatory. Our 2-D fitting analysis shows that the host galaxy of MARK 478 has the bulge to the total luminosity ratio of 0.3. And the residual image, after subtracting point spread function (PSF), bulge and disk components, shows that the host galaxy has an arm-like feature that could be a spiral arm or a feature from minor merging. We also show that the structural parameters obtained from our 2-D fitting match well with those derived from HST image. The promising result suggests that studies of low redshift AGN host galaxies are possible with data from a small telescope. In order to allow a statistical analysis, we hope to expand our sample size in future.

• JSTS:Journal of Semiconductor Technology and Science
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• 제15권2호
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• pp.292-300
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• 2015

This paper proposes a high-efficiency, dual-mode PWM / linear buck converter with a wide-input range. The proposed converter was designed with a mode selector that can change the operation between PWM / linear mode by sensing a load current. The proposed converter operates in a linear mode during a light load and in PWM mode during a heavy load condition in order to ensure high efficiency. In addition, the mode selector uses a bit counter and a transmission gate designed to protect from a malfunction due to noise or a time-delay. Also, in conditions between $-40^{\circ}C$ and $140^{\circ}C$, the converter has variations in temperature of $0.5mV/^{\circ}C$ in the PWM mode and of $0.24mV/^{\circ}C$ in the linear mode. Also, to prevent malfunction and breakdown of the IC due to static electricity, the reliability of IC was improved by embedding a self-produced 8 kV-class(Chip level) ESD protection circuit of a P-substrate Triggered SCR type with high robustness characteristics.

• 대한한방소아과학회지
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• 제14권2호
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• pp.33-46
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• 2000

It has long been known that Jahage(紫河車) extracts of Placenta hominis are effective for immunological and vascular diseases in human body and thus, was used a major constituent of traditional oriental medicines. From full-term human placenta, we have purified a new type anticoagulant protein, PP27, using different chromatographic techniques of a phenyl TSK gel 650M column, DEAE, HA and Mono-Q columns. PP27 showed single band on SDS-PAGE with a molecular mass (Mr) of 27 kDa under denaturing conditions and a calibrated Sepharose 4B column chromatography indicated a molecular mass of 23 kDa, indicating that the value is similar to those of other PP4 enzyme reported to date. Isoelectric point of PP27 was p15.2. The protein was found to inhibit the coagulation time in a concentration-dependent manner. PP27 was acted as a vascular anticoagulant of annexin type, inhibits the blood clotting process by binding of the essential lipids in a reaction which is dependent on $Ca2^+$ ions. In the presence of $Ca2^+$ ions, PP27 combines with platelet membranes neutralizing their procoagulant effect. Coagulation triggered by the addition of thromboplastin/ lipid- mixtures is extinguished by PP27.

• BMB Reports
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• 제41권10호
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• pp.728-732
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• 2008

FoxO3a is a member of the forkhead box class O (FoxO) transcription factor family and an important regulator of apoptosis. This work aimed to elucidate the involvement of FoxO3a in transforming growth factor-${\beta}1$(TGF-${\beta}1$)-induced apoptosis in FaO rat hepatoma cells. TGF-${\beta}1$ caused a time-dependent activation of FoxO3a and a subsequent increase in FoxO response-element-containing luciferase reporter activity, which was Akt-sensitive. The FaO cells stably transfected with a wild type FoxO3a were more susceptible to the formation of apoptotic bodies, populations of sub-G1 apoptotic cells, and collapse of the mitochondrial-membrane potential triggered by TGF-${\beta}1$. In contrast, transfection with small-interfering RNA (siRNA) oligonucleotide specific for FoxO3a significantly inhibited caspase activation in FaO cells treated with TGF-${\beta}1$. It thus appears that FoxO3a plays a crucial mediatory role in the TGF-${\beta}1$ signaling pathway leading to apoptosis.