• 한국정보과학회논문지:소프트웨어및응용
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• 제30권1_2호
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• pp.129-139
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• 2003

인터넷과 같은 대량의 정보에 대응할 수 있는 고성능 정보검색시스템을 구축하기 위해서는 지금까지 고가의 중대형컴퓨터를 주로 활용하여 왔으나. 최근 가격대 성능비가 높은 PC 클러스터 시스템을 활용하는 방안이 경제적인 대안으로 떠오르고 있다. PC 클러스터 상에서의 병렬정보검색시스템을 효율적으로 운영하기 위해서는 사용자가 입력한 질의를 처리하는데 요구되는 개별 PC의 디스크 I/O 및 검색관련 연산을 모든 PC에 가능한 균등하게 분배할 필요가 있다. 본 논문에서는 같은 질의에 동시에 등장할 가능성이 높은 색인어들끼리 군집화하고 생성된 군집을 활용하여 색인어들을 각 PC에 분배함으로써 보다 높은 수준의 병렬화를 달성할 수 있는 방안을 제시한다. 또한 일부 PC의 결함 또는 유지보수 등의 원인에 의한 서비스 중지상황에도 적극적으로 대처하기 위하여 색인어 역파일을 중복되게 분산저장하는 기법을 제안한다. 대용량 말뭉치를 활용한 실험결과 본 논문에서 제시하는 분산 및 중복저장기법이 충분한 효율성과 실용성이 있음을 확인하였다.

• 한국항해학회지
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• 제20권2호
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• pp.1-13
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• 1996

Most of the ShipHandling Simulators of full-mission-bridge system need vast area to install and even PC-based maneuvering simulators are often equipped with Steering Wheel or Engine Telegraphe etc. of data input interface, which necessarily makes the user face with excessive financial burden. These have been one of the obstacles for the officers, captains, pilots and students in access to maneuvering simulation whenever they want to try it in advance prior to actual ship maneuvering. Subsequently, all the officers and captains come to have little chances to train themselves until they arualified as a pilot after a long period of time of realship maneuvering practice on board, which means they have to control they have to control their own ship at sea without clear understanding on her maneuverability when they are forced to do it on the way. And these lack of capability for maneuvering have used so often to result in marine casualties of collision with other ships or pier facilities while maneuvering in harbor. To prevent those accidents by means of enhancing their maneuvering ability, PC-based DeskTop Simulator that allows anyong to access readily at anytime is needed and in conformation to such demand this simulator has been developed. The Software this simulator written in Turbo Pascal Ver. 5.0 has adopted MMG mathmatical model theoretically in part and also it was designed to make it possible that all numeric data inputs and outputs with graphic presentation for maneuvering operation be carried out just only with keyboard and monitor console. With the Simulation software, all the officers, captains, pilots and even students who has a proper computer at hand are expected to be able to make an attempt to simulate the maneuvering of their ownship or any other types of them at any port in which they want to do it.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.66-69
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• 2006

Three reinforced concrete rigid frames and infilled rigid frames with new retrofitting system were tested under both vertical and cyclic loadings, Experimental programs were carried out to evaluate and improve the seismic performance of such test specimens, such as the hysteretic behavior, the maximum horizontal strength, crack propagation, and ductility etc. under load reversals. All the specimens were modeled in one-third scale size. For specimens(RFHPC, RFAR) designed by the improving of seismic performance of the rigid frame using the high ductile fiber composite PC panel and ALC panel system, load-carrying capacities were increased $1.45{\sim}2.28$ times, and hysteretic behavior was very stable during the final tests in comparison with the standard specimen(SRF).

• 한국통신학회논문지
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• 제37권8A호
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• pp.612-617
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• 2012

다중 송신안테나 통신시스템에서 송신 안테나의 위상을 제어하는 두 가지 방법을 제안한다. 첫 번째 방법은 첫 번째 안테나의 위상을 기준으로 나머지 송신안테나들이 최대한 첫 번째 안테나와 위상을 가깝게 조절하는 기법이다. 두 번째 방법은 특정한 섹터를 정한 다음, 그 섹터로 모든 송신 안테나들의 위상을 일치시키는 기법이다. 컴퓨터 모의실험을 통하여 첫 번째 위상 조절기법이 두 번째 위상조절기법보다 우수하다는 것을 보일 수 있다. 그리고 첫 번째 위상 조절기법이 송신안테나 갯수가 4개일때 직교 시공간부호의 성능보다 1.2 dB 우수함을 알 수 있다.

• 한국정보과학회논문지:정보통신
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• 제36권6호
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• pp.552-557
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• 2009

일회용 암호는 한 번 사용하고 버리는 특성으로 인해 동일한 암호를 반복 사용하는 기존의 방법에 비해 훨씬 안전하다. 본 논문에서는 사용자들이 늘 휴대하고 다니는 휴대폰 상에서 동작하는 챌린지-응답(challenge-response) 방식의 일회용 암호 생성기를 제안한다. 이 암호 생성기는 추가의 인증 수단을 제공함으로써 PC 인터넷 뱅킹에서 계좌 이체 트랜잭션 명령을 내릴 때 사용할 수 있다. 현재 인터넷 뱅킹용으로 사용되는 별도의 일회용 암호 생성 장치는 30초 시간 동기화를 통해 계속 새로운 암호를 생성하기 때문에 동기화 주기 이내에는 여전히 중간자 공격의 가능성이 남아있다. 이에 비해 제안 방법은 정교한 챌린지-응답 방식을 통해 중간자 공격에 대비할 수 있고, 휴대성이 뛰어나며, 도난의 경우에도 더 안전하다. 또한 현재 쓰이는 장치와 마찬가지로, PC에 설치된 키보드 로거 등의 스파이웨어를 통해 공격 대상자의 모든 다른 인증 정보가 노출되더라도 제안 방법은 불법 이체 행위를 막을 수 있다.

• Journal of Korean Neurosurgical Society
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• 제43권2호
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• pp.79-84
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• 2008

Objective: The length of anterior-posterior commissure (AC-PC) in racial groups, age, gender of patients with deep brain stimulation (DBS) and pallidotomy were investigated. Methods: From January 1996 to December 2003, 211 patients were treated with DBS and pallidotomy. There were 160 (76%) Caucasians, 35 (17%) Hispanics, 12 (5%) Asians and 4 Blacks (2%). There were 88 males and 52 females in DBS-surgery group and 44 males, 27 females in pallidotomy group. Mean age was 58 year-old. There were 19 males and 19 females and mean age was 54.7 years in the control group. Measurements were made on MRI and @Target software. Results: The average AC-PC distance was 24.89 mm (range 32 to 19), which increased with aging until 75 years old in Caucasian and also increased with aging in Hispanic, but the AC-PC distance peaked at 45 years old in Hispanic. The order of AC-PC distance were $24.6{\pm}2$ mm in Caucasian, $24.6{\pm}2.24$ mm in Asian, 24.53 mm in Black, $23.6{\pm}1.98$ mm in Hispanic. The average AC-PC distance in all groups was 24.22 mm in female who was mean age of 56.35, 25.28 mm in male who was mean age of 60.19 and $24.5{\pm}2$ mm in control group that was excluded because of the difference of thickness of slice. According to multiple regression analysis, the AC-PC distance was significantly correlated with age, race, and gender. Conclusion: The AC-PC distance is significantly correlated with age, gender, and race. The atlas of functional stereotaxis would be depended on the Variation of indivisual brain that can influenced by aging, gender, and race.

• 전자통신동향분석
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• 제29권6호
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• pp.31-42
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• 2014

2007년 애플의 아이폰 출시 이후에 본격적으로 터치센서 시장이 성장하면서, 최근에는 스마트폰 뿐만 아니라 태블릿 PC, 노트북 PC, AIO(All-in-One)-PC 및 DID(Digital Information Display) 등 각종 디스플레이 제품으로 응용이 확대되고 있다. 터치패널 시장은 장기적으로 이러한 IT 제품을 넘어 자동차 시장과 같은 타 분야로 확대될 잠재력이 높다. 터치센서 기술은 슬림화, 경량화, 다기능화 등을 지향하는 고기능화 전략과 시장지배력을 확보하기 위한 저가격화 전략이 상충되면서 단일 전극층 터치센서, 플랙시블 터치센서, 내장형 터치센서, 대면적 터치센서, 지문인식 및 디지타이저 등이 내재화된 다기능 융/복합 터치센서의 개발이 촉진될 것으로 예측된다. 본고에서는 이러한 터치센서 기술동향과 산업동향을 기술하고자 한다.

• 생물정신의학
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• 제10권2호
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• pp.126-132
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• 2003

Objectives:The purpose of this study is to examine the effects of venlafaxine, one of novel antidepressant drugs, on neurite growth in PC12 cells. Methods:PC12 cells were cultured with NGF for eight days. Then different concentrations($0{\mu}M$, $1{\mu}M$, $5{\mu}M$) of venlafaxine were mixed with cultured PC12 cells. After 24 hours and 48 hours of culture, we compared the effects of venlafaxine on the total length of neurites of cultured PC12 cells between no venlafaxine treated group($0{\mu}M$) and venlafaxine treated groups($1{\mu}M$ and $5{\mu}M$). Additionally, we studied the concentration-dependent effect of venlafaxine on differentiation in PC12 cells. Results:Experimental results showed that 1) the mean length of neurites in $1{\mu}M$ and $5{\mu}M$ venlafaxine treated group was more increased than no venlafaxine treated group(p=0.002). 2) the length of neurite in $5{\mu}M$ venlafaxine treated group was more elongated than $1{\mu}M$ venlafaxine treated group(p=0.046). 3) the length of neurite in $6{\mu}M$ venlafaxine treated group was more elongated than all the other concentrations in our experiment. Above $6{\mu}M$, the length of neurite was shortened in inverse proportion to the concentration of venlafaxine. Conclusions:This results suggest that venlafaxine, one of novel antidepressant drugs, promotes the differentiation of neuron. This study is believed to be a first step toward understanding the molecular and cellular mechanisms of antidepressant treatment.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5727-5731
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• 2015

Background: There is a long standing interest in natural compounds especially those with a high polyphenolic content and high scavenging activity for hazardous free radicals. Cornus mas (CM) fruit is well known for its antioxidant activities; however, its toxicity against human cancers needs to be addressed. Here, we investigated selective anticancer effects of CM on different human cancer cells. Materials and Methods: A hydro-alcoholic extract of CM (HECM) was prepared and total phenolic content (TPC) and total flavonoid content (TFC) were determined by colorimetric assays. Antioxidant activity was assessed with respectto DPPH radical scavenging. MTT assays were used to evaluate the cytotoxicity of different doses of CM (0, 5, 20, 100, 250, 500, $1000{\mu}g/ml$) towards A549 (lung non small cell cancer), MCF-7 (breast adenocarcinoma), SKOV3 (ovarian cancer) and PC-3 (prostate adenocarcinoma) cells. Results: Significant (P<0.05) or very significant (P<0.001) differences were observed in comparison to negative controls at all tested doses ($5-1000{\mu}g/ml$). In all cancer cells, HECM reduced the cell viability to values below 26%, even at the lowest doses. In all cases, $IC_{50}$ was obtained at doses below $5{\mu}g/ml$. The mean growth inhibition was 81.8%, 81.9%, 81.6% and 79.3% in SKOV3, MCF-7, PC-3 and A549 cells, respectively. Conclusions: Altogether, to our best knowledge, this is a first study that evaluated toxicity of a HECM with high antioxidant activity in different human cancer cells in vitro. Our results indicated that a hydro-alcoholic extract of CM possesses high potency to inhibit proliferation of different tumor cells in a dose independent manner, suggesting that an optimal biological dose is more important and relevant than a maximally tolerated one.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5703-5707
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• 2015

Background: Medicinal plants, especially examples rich in polyphenolic compounds, have been suggested to be chemopreventive on account of their antioxidative properties. Melissa officinalis L. (MO), an aromatic and medicinal plant, is well known in thios context. However, toxicity against cancer cells has not been fully studied. Here, we investigated the selective anticancer effects of an MO extract (MOE) in different human cancer cells. Materials and Methods: a hydro-alcoholic extract of MO was prepared and total phenolic content (TPC) and total flavonoid content (TFC) were determined by colorimetric assays. Antioxidant activity was determined by DPPH radical scavenging activity. MTT assays were used to evaluate cytotoxicity of different doses of MOE (0, 5, 20, 100, 250, 500, $1000{\mu}g/ml$) towards A549 (lung non small cell cancer cells), MCF-7 (breast adenocarcinoma), SKOV3 (ovarian cancer cells), and PC-3 (prostate adenocarcinoma) cells. Results: Significant (P<0.01) or very significant (P<0.0001) differences were observed in comparison to negative controls at all tested doses ($5-1000{\mu}g/ml$). In all cancer cells, MOE reduced the cell viability to values below 33%, even at the lowest doses. In all cases, $IC_{50}$ values were below $5{\mu}g/ml$. The mean growth inhibition was 73.1%, 86.7%, 79.9% and 77.8% in SKOV3, MCF-7 and PC-3 and A549 cells, respectively. Conclusions: Our results indicate that a hydro-alcoholic extract of MO possess a high potency to inhibit proliferation of different tumor cells in a dose independent manner, suggesting that an optimal biological dose is more important than a maximally tolerated one. Moreover, the antiprolifreative effect of MO seems to be tumor type specific, as hormone dependant cancers were more sensitive to antitumoral effects of MOE.