• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.157-160
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• 2002

The dosage of intra-operative BNCT using near-threshold $^{7}$ Li(p,n)$^{7}$ Be direct neutrons was evaluated with the calculation method validated with the phantom experiment. The production of both neutrons by near-threshold $^{7}$ Li(p,n)$^{7}$ Be and gamma rays by $^{7}$ Li(p,p'gamma)$^{7}$ Li in a Li target was calculated using Lee's method and their transport in the phantom was calculated with MCNP-4B. As a result, the region satisfying the requirements of the protocol in intra-operative BNCT for brain tumors in Japan was acknowledged to be comparable to present BNCT, for the proton energy of 1.900 MeV for example. A boron-dose enhancer (BDE) introduced in this study to increase $^{10}$ (n,$\alpha$)$^{7}$ Li dose in a living body was effective. The void used to increase doses in deep regions was also valid with the BDE. It was found that intra-operative BNCT using near-threshold $^{7}$ Li(p,n)$^{7}$ Be direct neutrons is feasible.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.417-421
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• 2004

Self-potential (SP) survey was carried out at Pohang geothermal field. SP measurement showed clear positive anomaly at northern part of the test wells, which can be a up-flow zone of the deep geothermal water due to electrokinetic potential generated by hydrothermal circulation. To give a clearer image of the fluid flow pattern around the test wells, a two-dimensional numerical simulation was applied to construct a numerical block model of the fluid flow system based on SP and magnetotelluric survey results. The result suggests existence of two high permeability zones including the main manifestation area in the northern part of the test wells.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04b
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• pp.685-688
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• 2001

IMT-2000 시스템의 서비스는 회선 방식의 음성 및 데이터 서비스를 지원하는 기존 시스템의 기능을 포함하면서 데이터 전송률을 최대 2Mbps로 광대역화하여 고속 데이터 전송 등의 멀티미디어 서비스를 제공하며 국제 표준화된 이동 전화망의 접속 표준을 사용하여 글로벌 로밍 서비스가 제공된다. 그 중 정보보호 서비스의 요구는 기존 이동통신 시장에서와 같이 중요한 부분으로써 이미 ITU-R에서는 그 동안 발생한 보안 침범의 유형을 분석하고 방어 방법에 대한 연구를 진행하고 있다. 그러므로 본 논문은 국내 정보통신망 환경에서 적용될 IMT-2000 보안기술의 개발과 보안 구조의 국제 표준기술 연구개발을 위하여 3GPP에서 연구중인 UMTS(유럽형 IMT-2000)에서 표준화 작업중인 보안 아키텍처와 여기서 사용하는 KASUMI 알고리즘을 분석한다.

• JOURNAL OF ELECTRICAL WORLD
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• s.318
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• pp.79-84
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• 2003

세계 공통의 휴대전화 방식에 대한 기대가 일면서 개발에 착수한 것은 아날로그방식이 서비스를 개시한지 얼마 되지 않은 1980년대 중반이었다. 이후 10여년의 세월이 흐르면서 세계적인 의견의 일치를 보고 관련 권고문을 완성해 나갔으며, 비로서 1999년 11월에 이르러 ITU-R(International Telecommunication Union the Radiocommunication Sector)이 IMT-2000의 무선인터페이스 상세사양의 권고(ITU-R M.1457)를 완성시켰다. 한편, 구체적인 제품화를 실현시키기 위해 유럽, 미국, 중국, 한국, 일본을 중심으로 한 관련국가 및 관련지역의 민간표준화기관이 파트너쉽을 형성하여, 공통 기술사양의 개발에 착수하였다. 최초의 기술사양이 1999년 12월에 완료되고, 2001년 10월에는 일본에서 도코모((주)NTT, 일본전신전화주식회사)가 세계 최초로 상용서비스를 시작하였다. 그리고, 공통 기술사양의 대상이 되는 서비스는 음성서비스에서 크게 발전하여 멀티미디어 서비스로 질적으로나 양적으로도 충실하게 추진되어 나가고 있다. 미쓰비시전기는 이 활동의 중요성에 재빨리 주목하여 초기단계에서부터 표준화 활동에 참여해 오고 있으며, 구체적인 작업이 표준화기관에서 시작함에 따라 전사적으로 조직을 정비하여 동사가 개발한 기술을 제안하여 왔다. 성과로서는 무선구간의 암호알고리즘에는 동사 보유기술의 MISTY 방식의 기술적 우위성이 인정되어 그것을 핵으로 하는 KASUMI 사양이 동사를 중심으로 한 전문가에 의해 개발된 것, MPEG 코덱사양, 음성 코덱과 무선전송방식의 개량 등을 위해 국제적인 공헌을 하여 온 것을 들 수 있다. 본고에서는 상기의 세계 공통기술사양개발에 오랜 세월 동안 많은 노력을 들여온 그 경위와 성과, 그리고 앞으로의 동향에 대해 설명한다.

• ALGAE
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• v.22 no.1
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• pp.37-44
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• 2007

In order to understand the impact of the heavy-oil pollution by the 1997 Nakhodka oil spill on the intertidal macroalgal vegetation, we have been monitoring succession in the intertidal flora since 1997 at Oh-ura, Takno, and Imago-Ura Cove, Kasumi in Hyogo Prefecture, northwestern coast of Honshu, Japan. We employed two different monitoring methods: 1) The percent cover of macro-algae (seaweeds) in 1 x 1 m quadrats along 450 m intertidal transects parallel to the shoreline were assessed and recorded by photographic imaging until 2002, and for 30-40 m transects of the most heavily polluted areas in 2004 and 2006; 2) The percent cover of macro-algae in 0.5 x 0.5 m quadrats along a transect line perpendicular to the shore were recorded and all macrophytes within the quadrat were completely removed to record the wet weight of each taxon (1997-2006). Based on the monitoring data, we conclude that the high intertidal zone at Imago-ura, where a large part of the stranded oil accumulated, suffered the heaviest damage and experienced the slowest recovery. In addition, although the original status of macroalgal vegetation before the impact was not well-documented, it appeared that recovery from the damage caused by the oil pollution required four to five years.

• Food Science and Preservation
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• v.6 no.4
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• pp.506-513
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• 1999

The growth of lactic acid bacteria was investigated in liquid broth medium containing organic germanium compound(Ge-132, carboxyethylgermanium sesquioxide) in the range of 0.01 to 10mg/ml. Most of all lactic acid bacteria tested were tolerant and could grow better to the high Ge-132 concentration. However, the growth of Leuconostoc mesenteroides and Pediococcus pentosaceus were inhibited in the presence of 10mg/m1 Ge-132. Among 22 strains tested, lactic acid bacteria that were grown to a high degree(about 2 times) by addition of Ge-132 (10mg/ml)were Lactococcus lactis, Lc. cremoris, Lc. diacetilactis, Enterococcus faecium and Streptococcus faecalis. The growth of these strains were markedly accelerated in the culture medium supplemented with 1.omg/ml Ge-132 The optimal concentration of glucose for growth of Lc. lactic was found to be high in medium containing Ge-132 as compared with the case of control. During cultivation viscosity in culture broths of Lc. lactis and Lc. cremoris was rapidly elevated by adding Ge-132 to medium containing high concentration of glucose, and then decreased after incubation of long time. However, in the cultivation of Lc. diacetilactis, E, faecium and S. faecalis, viscosity of culture broths was not increased, even though Ge-132 was shown to be an effective stimulant of growth.

• BMB Reports
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• v.51 no.9
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• pp.444-449
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• 2018

Acute myeloid leukemia (AML) is one of the most common hematological malignancies all around the world. MicroRNAs have been determined to contribute various cancers initiation and progression, including AML. Although microRNA-204 (miR-204) exerts anti-tumor effects in several kinds of cancers, its function in AML remains unknown. In the present study, we assessed miR-204 expression in AML blood samples and cell lines. We also investigated the effects of miR-204 on cellular function of AML cells and the underlying mechanisms of the action of miR-204. Our results showed that miR-204 expression was significantly downregulated in AML tissues and cell lines. In addition, overexpression of miR-204 induced growth inhibition and apoptosis in AML cells, including AML5, HL-60, Kasumi-1 and U937 cells. Cell cycle analysis further confirmed an augmentation in theapoptotic subG1 population by miR-204 overexpression. Mechanistically, baculoviral inhibition of apoptosis protein repeat containing 6 (BIRC6) was identified as a direct target of miR-204. Enforcing miR-204 expression increased the luciferase activity and expression of BIRC6, as well as p53 and Bax expression. Moreover, restoration of BIRC6 reversed the pro-apoptotic effects of miR-204 overexpression in AML cells. Taken together, this study demonstrates that miR-204 causes AML cell apoptosis by targeting BIRC6, suggesting miR-204 may play an anti-carcinogenic role in AML and function as a novel biomarker and therapeutic target for the treatment of this disease.

• Geophysics and Geophysical Exploration
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• v.7 no.3
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• pp.164-173
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• 2004

To delineate geothermal water movement at the Pohang geothermal development site, Self-Potential (SP) survey and monitoring were carried out during pumping tests. Before drilling, background SP data have been gathered to figure out overall potential distribution of the site. The pumping test was performed in two separate periods: 24 hours in December 2003 and 72 hours in March 2004. SP monitoring started several days before the pumping tests with a 128-channel automatic recording system. The background SP survey showed a clear positive anomaly at the northern part of the boreholes, which may be interpreted as an up-flow Bone of the deep geothermal water due to electrokinetic potential generated by hydrothermal circulation. The first and second SP monitoring during the pumping tests performed to figure out the fluid flow in the geothermal reservoir but it was not easy to see clear variations of SP due to pumping and pumping stop. Since the area is covered by some 360 m-thick tertiary sediments with very low electrical resistivity (less than 10 ohm-m), the electrokinetic potential due to deep groundwater flow resulted in being seriously attenuated on the surface. However, when we compared the variation of SP with that of groundwater level and temperature of pumping water, we could identify some areas responsible to the pumping. Dominant SP changes are observed in the south-west part of the boreholes during both the preliminary and long-term pumping periods, where 3-D magnetotelluric survey showed low-resistivity anomaly at the depth of $600m\~1,000m$. Overall analysis suggests that there exist hydraulic connection through the southwestern part to the pumping well.