• 제목/요약/키워드: out-migration

검색결과 467건 처리시간 0.026초

성능 기반 태스크 할당을 이용한 웹 기반 병렬처리 시스템의 설계 (Design of Web-based Parallel Processing System using Performance-based Task Allocation)

  • 한연희;박찬열;정영식;황종선
    • 한국정보과학회논문지:시스템및이론
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    • 제27권3호
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    • pp.264-276
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    • 2000
  • 최근 인터넷 환경에서의 기술 향상으로 인하여 다양한 정보를 공유하고, 네트워크로 연결된 여러 시스템 자원을 이용하는 것이 용이하게 되었다. 특히, 자바의 애플릿(applet)을 이용한 코드 이동(code migration) 기술은 인터넷의 웹 환경에서 프로그램의 분산을 용이하게 하며, 그 애플릿을 수행하는 브라우저는 이동된 코드의 신뢰성을 보장해준다. 본 논문은 웹 환경에서 이동 가능 코드를 분산시키고, 대량의 연산수행을 지닌 작업을 분배하여 병렬적으로 수행시킨 뒤, 그 결과를 취합하는 웹 기반 병렬 시스템의 설계 및 구현에 관하여 기술한다. 또한, 이 시스템에 참여하는 이질적인 다수의 호스트들은 인터넷이라는 환경에서 지리적으로 떨어져 연결되어 있으므로 성능의 차이 및 가변성을 예상하기 힘들다. 그러므로, 그들 간의 성능 차이를 고려한 태스크 할당 알고리즘 및 심각한 가변성에 대한 적응력이 요구된다. 이 논문에서는 시스템의 구현에 사용될 적응성 향상 기법을 제시하고, 시스템의 작업 처리 성능 및 제안하는 알고리즘들의 효율을 나타내는 성능 평가 결과를 제시한다.

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도심지역 산지형 근린공원내 도로에 의한 단절지역 생물이동통로 조성계획 연구 - 동작구 노량진근린공원을 대상으로 - (An Ecological Corridor Plan in an Urban Neighborhood Park - A Case Study of Noryangjin Neighborhood Park in Dongjak-gu, Seoul -)

  • 한봉호;김정호;김종식
    • 한국조경학회지
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    • 제33권2호
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    • pp.16-31
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    • 2005
  • This study was carried out to design a bridge-type ecological corridor plan in a forested neighborhood park affected by road construction in Dongjak-gu, Seoul. In order to study the site conditions, we analyzed topography, ecosystem structure, and user behavior and trail use. Existing vegetation was classified into 12 types. Based on a vegetation analysis, the Populus albaglandulosa and Robinia pseudoacacia communities, where planted species are dominant, were distributed extensively in the southern forest area. Planted areas with a single-layer structure of Korean landscape woody plants and Robinia pseudoacacia communities with a single-layer structure were distributed extensively in the northern forest and water-supply area. Based on a study of 28 quadrats, the similarity index between the multi-layer plant communities distributed in the southern forest and the single-layer planted areas was low. Twenty-four species of wild birds(355 individuals) were found in the survey area, including nine interior species and three urban species. The study of user behavior and numbers showed most users were walkers and few users were observed in the southern forest while most users were observed in the northern forest and water supply area. We selected some wild birds as model species to represent migrating species believed to use this park as an ecological corridor during migration. We suggested the new park plan include the following: improvement of vegetation structure for wildbird migration and habitat, connection of park trails for users and presentation of a landscape linked to nature.

지하유류비축공동(地下油類備蓄空洞)에서 Water Curtain의 효율성(効率性)에 관한 연구(硏究) (A Study on the Efficiency of Water Curtain around the Underground Oil Storage Cavern)

  • 정형식;이익효
    • 대한토목학회논문집
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    • 제3권3호
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    • pp.87-94
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    • 1983
  • 지하유류비축공동(地下油類備蓄空洞)의 성패(成敗)는 공동상부(空洞上部)에 충분(充分)한 수두(水頭)를 유지(維持)하여 공동주위(空洞周圍)의 수밀성(水密性)을 보장(保障)하는 데 있다. 공동상부(空洞上部)에 충분(充分)한 수두(水頭)가 유지(維持)되면 저장(貯藏)된 유류(油類)의 Gas가 누출(漏出)되지 않으며, 인접공동(隣接空洞)이 비어있을 때에도 이곳으로 유류(油類)는 이동(移動)되지 않는다. 본(本) 연구(硏究)에서는 전기상사모형실험(電氣相似模型實驗)을 통(通)하여 수평(水平) 및 수직(垂直) Water Curtain을 설치(設置)하여 Gas 누출(漏出)과 유류이동(油類移動)을 방지(防止)하려 할 때 효과적(効果的)인 Water Curtain의 위치(位置), 인접공동간격(隣接空洞間隔) Water Curtain 수두(水頭), Bore-hole 간격 등이 검토(檢討)되었다. 연구결과(硏究結果) 공동(空洞)의 간격(間隔)이 좁으면 수직(垂直) Water Curtain은 꼭 설치(設置)되어야 하며, 공동간격(空洞間隔)이 공동(空洞) 높이의 2배 이상 커지면 수직(垂直) Water Curtain은 필요(必要)없다는 것이 입증(立證)되었고 유류이동(油類移動)을 방지(防止)하는데 필요(必要)한 수평(水平) 및 수직(垂直) Water Curtain의 위치(位置), Water Curtain 수두(水頭), Bore hole 간격 등이 도표(圖表)로 주어졌다.

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Studies of Silyl-Transfer Photochemical Reactions of N-[(Trimethylsilyl)alkyl]saccharins

  • Cho, Dae-Won;Oh, Sun-Wha;Kim, Dong-Uk;Park, Hea-Jung;Xue, Jin-Ying;Yoon, Ung-Chan;Mariano, Patrick S.
    • Bulletin of the Korean Chemical Society
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    • 제31권9호
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    • pp.2453-2458
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    • 2010
  • Photochemical studies of N-[(trimethylsilyl)alkyl]saccharins were carried out to investigate their photochemical behavior. Depending on the nature of the substrate and the solvent system employed, reactions of these substances can take place by either SET-promoted silyl migration from carbon to either the amide carbonyl or sulfonyl oxygen or by a N-S homolysis route. The results of the current studies show that an azomethine ylide, arising from a SET-promoted silyl migration pathway, is generated in photoreactions of N-[(trimethylsilyl)methyl]saccharin and this intermediate reacts to give various photoproducts depending on the conditions employed. In addition, irradiation of N-[(trimethylsily)ethyl]saccharin produces an excited state that reacts through two pathways, the relative importance is governed by solvent polarity and protic nature. Finally, photoirradiation of N-[(trimethylsilyl)propyl]saccharin in a highly polar solvent system comprised of 35% aqueous MeOH gives rise to formation of a tricyclic pyrrolizidine and saccharin that generated via competitive SET-promoted silyl transfer and $\gamma$-hydrogen abstraction pathways.

Hydrolysis Mechanisms of Fish Oil by Lipolase-100T

  • HUR, BYUNG-KI;DONG-JIN WOO;CHONG-BO KIM
    • Journal of Microbiology and Biotechnology
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    • 제9권5호
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    • pp.624-630
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    • 1999
  • In order to investigate the position of various fatty acids attached to glycerol and the specificity of Lipolase-100T, hydrolysis of fish oil was carried out with Lipolase-100T derived from Aspergillus oryzae. The amounts of free fatty acids produced from triglyceride, 1,2(2,3)-diglyceride, 1,3-diglyceride, and 2-monoglyceride and conversion rates of 1,2(2,3)-diglyceride to 1,3-diglyceride and 2-monoglyceride to 1(3)-monoglyceride were also calculated. The ratio of 1,2-diglyceride content to 1,3-diglyceride was higher than 70 in the early period of hydrolysis. The fatty acid content of the glyceride mixture after 72 h of hydrolysis was compared with that of fish oil, and it was found that polyunsaturated fatty acids such as C16:4, C20:4 n-3, C20:5 n-3, C21:5 n-3, C22:5 n-3 and C22:6 n-3 were located in the 2-position of glycerol. Material balance of each component in the hydrolysis system was written to obtain a set of simultaneous linear equations. The theoretical quantity of free fatty acids produced from triglyceride, 1,2-diglyceride, 1,3-diglyceride, and monoglyceride, respectively, were calculated by solving the linear equation system. The conversion rate of 1,2(2,3)-diglyceride to 1,3-diglyceride and that of 2-monoglyceride to 1(3)-monoglyceride were also obtained. The results showed that the migration rate of 1,2(2,3)-diglyceride to 1,3-diglyceride was higher than the hydrolysis rate of 1,2(2,3)-diglyceride to 2-monoglyceride and the conversion rate of 2-monoglyceride to 1(3)-monoglyceride was extremely low.

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영산강유역 대형옹관의 태토 특성에 의한 분류 (Characterization of Large-sized Jar-coffins from Youngsan River by the Elemental Analysis)

  • 이한형;홍종욱;황진주;박지희;문은정;김수경;정용삼;문종화
    • 보존과학연구
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    • 통권30호
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    • pp.103-124
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    • 2009
  • Major and trace elements and cross section textures of the large-sized jar-coffins excavated in the Young San river area have been analyzed for categorization according to geochemical characteristics of the raw materials. As results, we have found out that the jar-coffins of the Oryang-dong and Ungok-dong have very similar characteristics, and those of Songwol-dong and Jangdeung show distinguishable characteristics from the others. In addition, similar characteristics have been detected in some U-shape jar-coffins from several sites such as Oryang-dong, Ungok-dong, Sinchon-ri, Mansu-ri and Yeon-ri posess on trace elements and cross section texture. These results indicate that there was active physical migration although the detail route of the physical migration is unclear at current stage.

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지하연구시설을 이용한 오염물질 이동실험 현황 및 과제 (Current Status and Tasks of Contaminant Migration Experiment Using Underground Research Laboratory)

  • 박정균;백민훈;최종원
    • 터널과지하공간
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    • 제17권1호
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    • pp.17-25
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    • 2007
  • 전세계적으로 방사성폐기물을 포함한 오염물질 심부처분관련연구는 실험실에서 단위현상들에 대한 관찰 및 자료측정부터 시작하지만, 이 실험자료들은 실제처분장조건을 완벽하게 구비한 상태에서 측정한 것이 아니므로 자료의 검증과 신뢰도 확보가 중요하다. 이런 부분 뿐만 아니라 공학적 규모에서 처분시스템의 성능평가를 위해 지하연구시설을 건설하여 관련연구를 진행하게 된다. 그렇지만, 지하연구시설은 많은 투자비가 든다는 점 외에 환경문제가 중요한 사회적 갈등으로 나타날 가능성이 많다. 이런 지하연구시설을 이용해 실험시 고려해야할 사항들을 검토하고, 세계적인 연구현황과 특징들을 기술하였다. 또, 한국에서 최근 비방사능실험시설로 소규모 지하연구시설을 인허가 받고 본격적인 연구시행단계에 진입하였는데, 오염물질이동관련 연구계획들을 중심으로 소개하였다.

가속수명시험을 이용한 Packaging Substrate PCB의 ECM에 대한 신뢰성 예측에 관한 연구 (A Study on the Reliability Prediction about ECM of Packaging Substrate PCB by Using Accelerated Life Test)

  • 강대중;이화기
    • 대한안전경영과학회지
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    • 제15권1호
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    • pp.109-120
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    • 2013
  • As information-oriented industry has been developed and electronic devices has come to be smaller, lighter, multifunctional, and high speed, the components used to the devices need to be much high density and should have find pattern due to high integration. Also, diverse reliability problems happen as user environment is getting harsher. For this reasons, establishing and securing products and components reliability comes to key factor in company's competitiveness. It makes accelerated test important to check product reliability in fast way. Out of fine pattern failure modes, failure of Electrochemical Migration(ECM) is kind of degradation of insulation resistance by electro-chemical reaction, which it comes to be accelerated by biased voltage in high temperature and high humidity environment. In this thesis, the accelerated life test for failure caused by ECM on fine pattern substrate, $20/20{\mu}m$ pattern width/space applied by Semi Additive Process, was performed, and through this test, the investigation of failure mechanism and the life-time prediction evaluation under actual user environment was implemented. The result of accelerated test has been compared and estimated with life distribution and life stress relatively by using Minitab software and its acceleration rate was also tested. Through estimated weibull distribution, B10 life has been estimated under 95% confidence level of failure data happened in each test conditions. And the life in actual usage environment has been predicted by using generalized Eyring model considering temperature and humidity by developing Arrhenius reaction rate theory, and acceleration factors by test conditions have been calculated.

Enzymatic reaction model for the production of symmetrical lipid molecules using the response surface methodology

  • Hong, Joon-Sun;Shin, Jung-Ah;Lee, Ki-Teak
    • 농업과학연구
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    • 제45권2호
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    • pp.265-282
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    • 2018
  • The purpose of this research was to produce symmetric (Saturated-Unsaturated-Saturated, SUS) triacylglycerol (TAG) using palm stearin fraction oil (PSFO) and high oleic sunflower oil (HOSO) as substrates to replace cocoa butter. PSFO was blended with HOSO (1 : 2 weight ratio), and $lipozyme^{(R)}$ TLIM (20 weight % of the substrate) was added. Interesterification was carried out in a shaking water bath at $55^{\circ}C$ at 220 rpm for 6 hours. The response surface methodology (RSM) through the central composite face design was employed to observe the optimized SUS-TAG. The independent factors were the reaction temperature ($X_1$: 65, 75 and $85^{\circ}C$), reaction time ($X_2$: 1, 3 and 5 hours) and ratio of TLIM ($X_3$: 10, 15 and 20 weight %). The dependent variables were $Y_1$ = Saturated-Unsaturated-Unsaturated (SUU, area %), $Y_2=SUS$ (area %), $Y_3$ = Saturated-Saturated-Unsaturated (SSU, area %), $Y_4$ = Unsaturated-Unsaturated-Unsaturated (UUU, area %), and $Y_5=sn-2$ unsaturated fatty acid (area %). The optimal conditions from the central composite face design minimized acyl migration while maximizing the presence of unsaturated fatty acid at the sn-2 position (73.43 area %). The optimal conditions were $X_1=65^{\circ}C$, $X_2=1hour$, and $X_3=20weight%$. As a result of the response surface analysis, the lack of fits was found as $Y_1=0.622$, $Y_2=0.438$, $Y_3=0.264$, $Y_4=0.526$, and $Y_5=0.215$, and their $R^2$ were 0.897, 0.944, 0.826, 0.857, and 0.867, respectively.

고령군의 다문화가정 지원현황과 과제 (The Phenomena and Problems of the Supporting Activities to the Multicultural Families in Goryeong-gun)

  • 조현미
    • 한국지역지리학회지
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    • 제14권4호
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    • pp.347-366
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    • 2008
  • 본격적인 글로벌시대를 맞이하여, 지역수준에서에서의 자본, 상품, 문화의 초국가적 이동과 교류가 활발히 진행되어가고 있는 가운데, 이동과 교류의 직접적인 장이 되고 있는 지역의 중요성이 부각되고 있다. 본 연구에서는 현재 국내에서 야기되고 있는 다문화담론의 주요 대상인 결혼이주여성에 초점을 맞추어 고령군에서 실시하고 있는 다문화 시책의 현황을 분석하고 문제점과 과제를 도출하고자 했다. 그 결과, 고령군의 다문화가정에 대한 지원은 고령군청과 교육청이 주축이 되어 실시하고 있었으나, 유사한 지원내용이 중점적으로 실시되고 있음에도 불구하고 관련기관간의 연계가 부족하여 지원내용을 개선하고 향상시키고자하는 노력은 나타나지 않았다. 지역에서의 다문화현상을 정확하게 인식하고, 그에 따른 적절한 내용과 지원을 하기 위해서는 지자체가 다문화가정에 대한 지원의 중심이 되어 지역 내의 자원과 인재를 적지적소에 활용하는 통합정책이 이루어져야 할 것이다.

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