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Analysis on Social Area of Taegu (대구시의 사회지역분석)

  • Choi, Seok-Joo
    • Journal of the Korean association of regional geographers
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    • v.3 no.2
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    • pp.209-225
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    • 1997
  • Today, rapid progress of urbanization is discovered commonly in many countries, especially in developing countries, which has led to spatial order and development process of city. Historically, Taegu was a walled city and formed mono-nucleus which was restricted by the castle. As the city grew gradually, the castle was removed as a result of diversification in traffic network, change of socio-economic environment, formation of industrial base and functional distribution. According to reconstruction maps of residential patterns, there was distinctive residential segregation among ethnic groups. Koreans in Taegu in 1939, aggregated densely in the southern and western parts of the city. The Japanese were concentrated densely in the northern and eastern parts of Taegu. And the street pattern within residential areas of the Korean people was shaped like a maze type in contrast with Japanese residential areas, which showed grid pattern of streets. This is another general pattern of almost all colonial cities, especially in Asia. Through this process, today it appears that, out of overall residential areas which occupy the highest ratio in urban land use, those for eminent people influence the functional development of urban spatial structure very heavily as a key point in urban residetial structure. Truly, residential segregation can be seen as the spatial manifestation of uneven distribution of such important scarce resources as housing and residential environment. In this study, the characteristics of locational distribution of the eminent people show their socially and economically stabilized standing in Taegu, taking the aforesaid situation as a background of the study. And the process of this study is as follows ; to examine the forming process of residential areas in the city as a theoretical supporting, to put in order on classical interpretation to formation of residential areas, and general type modern residential areas formation, and economic decision factor of land use. Therefore, this study aims to examine growth and development of eminent persons' residential areas and, at the same time, extract locational characteristics through the pattern of eminent persons' location and predict changes in the future.

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Development of Cyber R&D Platform on Total System Performance Assessment for a Potential HLW Repository ; Application for Development of Scenario through QA Procedures (고준위 방사성폐기물 처분 종합 성능 평가 (TSPA)를 위한 Cyber R&D Platform 개발 ; 시나리오 도출 과정에서의 품질보증 적용 사례)

  • Seo Eun-Jin;Hwang Yong-soo;Kang Chul-Hyung
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.06a
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    • pp.311-318
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    • 2005
  • Transparency on the Total System Performance Assessment (TSPA) is the key issue to enhance the public acceptance for a permanent high level radioactive repository. To approve it, all performances on TSPA through Quality Assurance is necessary. The integrated Cyber R&D Platform is developed by KAERI using the T2R3 principles applicable for five major steps in R&D's. The proposed system is implemented in the web-based system so that all participants in TSPA are able to access the system. It is composed of FEAS (FEp to Assessment through Scenario development) showing systematic approach from the FEPs to Assessment methods flow chart, PAID (Performance Assessment Input Databases) showing PA(Performance Assessment) input data set in web based system and QA system receding those data. All information is integrated into Cyber R&D Platform so that every data in the system can be checked whenever necessary. For more user-friendly system, system upgrade included input data & documentation package is under development. Throughout the next phase R&D, Cyber R&D Platform will be connected with the assessment tool for TSPA so that it will be expected to search the whole information in one unified system.

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Design and Implementation of an Execution-Provenance Based Simulation Data Management Framework for Computational Science Engineering Simulation Platform (계산과학공학 플랫폼을 위한 실행-이력 기반의 시뮬레이션 데이터 관리 프레임워크 설계 및 구현)

  • Ma, Jin;Lee, Sik;Cho, Kum-won;Suh, Young-kyoon
    • Journal of Internet Computing and Services
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    • v.19 no.1
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    • pp.77-86
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    • 2018
  • For the past few years, KISTI has been servicing an online simulation execution platform, called EDISON, allowing users to conduct simulations on various scientific applications supplied by diverse computational science and engineering disciplines. Typically, these simulations accompany large-scale computation and accordingly produce a huge volume of output data. One critical issue arising when conducting those simulations on an online platform stems from the fact that a number of users simultaneously submit to the platform their simulation requests (or jobs) with the same (or almost unchanging) input parameters or files, resulting in charging a significant burden on the platform. In other words, the same computing jobs lead to duplicate consumption computing and storage resources at an undesirably fast pace. To overcome excessive resource usage by such identical simulation requests, in this paper we introduce a novel framework, called IceSheet, to efficiently manage simulation data based on execution metadata, that is, provenance. The IceSheet framework captures and stores each provenance associated with a conducted simulation. The collected provenance records are utilized for not only inspecting duplicate simulation requests but also performing search on existing simulation results via an open-source search engine, ElasticSearch. In particular, this paper elaborates on the core components in the IceSheet framework to support the search and reuse on the stored simulation results. We implemented as prototype the proposed framework using the engine in conjunction with the online simulation execution platform. Our evaluation of the framework was performed on the real simulation execution-provenance records collected on the platform. Once the prototyped IceSheet framework fully functions with the platform, users can quickly search for past parameter values entered into desired simulation software and receive existing results on the same input parameter values on the software if any. Therefore, we expect that the proposed framework contributes to eliminating duplicate resource consumption and significantly reducing execution time on the same requests as previously-executed simulations.

Geochemical Studies of the Trace Element of the Basalt in the Kilauea, Hawaii (킬라우에아 현무암의 미량원소에 대한 지구화학적 연구)

  • Park, Byeong-Jun;Jang, Yun-Deuk;Kwon, Suk-Bom;Kim, Jeong-Jin
    • Economic and Environmental Geology
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    • v.40 no.5
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    • pp.675-689
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    • 2007
  • Kilauea volcano's summit area was formed by continuous ind/or sporadic eruption activities for several hundreds years. In this study, we mainly focused on the trace elements characteristics through systematic sample rocks erupted from 1790 to September of 1982. Under the microscope it can be observed some main minerals such as olivine, clinopyroxene. and plagioclase with minor opaque minerals including Cr-spinel and ilmenite. Zr, V, Y, Ti elements show incompatible activities with MgO while Ni, Cr, Co elements show highly compatible properties. Elements like as Ba, Rb, Th, Sr, Nd are highly incompatible to show positive trends with $K_2O$. In the REE diagram LREE is more enriched than HREE suggesting typical Oceanic Island Basalt(OIB) type. It can be suggested that Sr have an effect on the fractionation of plagioclase from the kink in the $K_2O$ variation diagram. Y/Ho ratio diagram shows there was no fluids effect in the historical Kilauea volcano but Zr/Hf ratio diagram shows a significant difference between Kilauea lavas and PuuOo lavas. There are distinctive changes of trace element contents showing in particular abrupt changes of temporal variations between 1924 and 1954. Moreover, PuuOo lavas which had been erupted since 1983 follow these decreasing trends of trace element variation. Therefore, it is strongly suggested that these abrupt changes of trace elements trends result from the huge collapse geological event which formed Halemaumau crater in 1924 causing contamination effects of crustal contents into magma chamber and from the changes of parental magma composition injected into Kilauea volcano's summit magma reservoir.

A personalized TV service under Open network environment (개방형 환경에서의 개인 맞춤형 TV 서비스)

  • Lye, Ji-Hye;Pyo, Sin-Ji;Im, Jeong-Yeon;Kim, Mun-Churl;Lim, Sun-Hwan;Kim, Sang-Ki
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2006.11a
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    • pp.279-282
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    • 2006
  • IP망을 이용한 IPTV 방송 서비스가 새로운 수익 모델로 인정받고 현재 국내의 KT, SKT 등이 IPTV 시범서비스를 준비하거나 진행 중에 있다 이 IPTV 서비스는 이전의 단방향 방송과는 달리 사용자와의 인터렉션을 중시하는 양방향 방송을 표방하기 때문에 지금까지의 방송과는 다른 혁신적인 방송서비스가 기대된다. 하지만 IPTV 서비스에 있어서 여러 통신사와 방송사가 참여할 수 있을 것으로 보여지는 것과는 달리 실상은 몇몇 거대 통신기업이 자신들의 망을 이용하는 가입자들을 상대로 한정된 사업을 벌이고 있다. 이는 IPTV 서비스를 위한 인프라가 구축되어 있지 않고 방통융합망의 개념을 만족시키기 위해 서비스 개발자가 알아야 할 프로토콜들이 너무나 많기 때문이다. 따라서 본 논문에서는 이러한 상황을 타개할 수 있는 수단을 Open API로 제안한다. 맞춤형 방송을 위한 시나리오를 TV-Anytime의 벤치마킹과 유저 시나리오를 참고하여 재구성하고 이 시나리오로부터 IPTV 방송 서비스를 위한 방통융합망의 기본적이고 강력한 기능들을 Open API 함수로 정의하였다. 여기에서의 방송 서비스는 NDR, EPG, 개인 맞춤형 광고 서비스를 말하며 각 서비스를 위한 서버는 통합망 위에 존재하고 이 서버들이 개방하는 API들은 다른 응용프로그램에 의해 사용되는 것이기 때문에 가장 기본적인 기능을 정의하게 된다. 또한, 제안한 Open API 함수를 이용하여 개인 맞춤형 방송 응용 서비스를 구현함으로써 서비스 검증을 하였다. Open API는 웹서비스를 통해 공개된 기능들로써 게이트웨이를 통해 다른 망에서 사용할 수 있게 된다. Open API 함수의 정의는 함수 이름, 기능, 입 출력 파라메터로 이루어져 있다. 사용자 맞춤 서비스를 위해 전달되는 사용자 상세 정보와 콘텐츠 상세 정보는 TV-Anytime 포럼에서 정의한 메타데이터 스키마를 이용하여 정의하였다.가능하게 한다. 제안된 방법은 프레임 간 모드 결정을 고속화함으로써 스케일러블 비디오 부호화기의 연산량과 복잡도를 최대 57%감소시킨다. 그러나 연산량 감소에 따른 비트율의 증가나 화질의 열화는 최대 1.74% 비트율 증가 및 0.08dB PSNR 감소로 무시할 정도로 작다., 반드시 이에 대한 검증이 필요함을 알 수 있었다. 현지관측에 비해 막대한 비용과 시간을 절약할 수 있는 위성영상해석방법을 이용한 방법은 해양수질파악이 가능할 것으로 판단되며, GIS를 이용하여 다양하고 복잡한 자료를 데이터베이스화함으로써 가시화하고, 이를 기초로 공간분석을 실시함으로써 환경요소별 공간분포에 대한 파악을 통해 수치모형실험을 이용한 각종 환경영향의 평가 및 예측을 위한 기초자료로 이용이 가능할 것으로 사료된다.염총량관리 기본계획 시 구축된 모형 매개변수를 바탕으로 분석을 수행하였다. 일차오차분석을 이용하여 수리매개변수와 수질매개변수의 수질항목별 상대적 기여도를 파악해 본 결과, 수리매개변수는 DO, BOD, 유기질소, 유기인 모든 항목에 일정 정도의 상대적 기여도를 가지고 있는 것을 알 수 있었다. 이로부터 수질 모형의 적용 시 수리 매개변수 또한 수질 매개변수의 추정 시와 같이 보다 세심한 주의를 기울여 추정할 필요가 있을 것으로 판단된다.변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다

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Analysis of a Sulfur-oxidizing Perchlorate-degrading Microbial Community (황 산화를 통해 퍼클로레이트를 분해하는 미생물 군집 분석)

  • Kim, Young-Hwa;Han, Kyoung-Rim;Hwang, Heejae;Kwon, Hyukjun;Kim, Yerim;Kim, Kwonwoo;Kim, Heejoo;Son, Myunghwa;Choi, Young-Ik;Sung, Nak-Chang;Ahn, Yeonghee
    • Journal of Life Science
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    • v.26 no.1
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    • pp.68-74
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    • 2016
  • Perchlorate (ClO4) is an emerging pollutant detected in surface water, soil, and groundwater. Previous studies provided experimental evidence of autotrophic ClO4 removal with elemental sulfur (S0) particles and activated sludge, which are inexpensive and easily available, respectively. In addition, ClO4 removal efficiency was shown to increase when an enrichment culture was used as an inoculum instead of activated sludge. PCR-DGGE was employed in the present study to investigate the microbial community in the enrichment culture that removed ClO4 autotrophically. Microorganisms in the enrichment culture showed 99.71% or more ClO4 removal efficiency after a 7-day incubation when the initial concentration was approximately 120 mg ClO4/l. Genomic DNA was isolated from the enriched culture and its inoculum (activated sludge), and used for PCR-DGGE analysis of 16S rRNA genes. Microbial compositions of the enrichment culture and the activated sludge were different, as determined by their different DGGE profiles. The difference in DGGE banding patterns suggests that environmental conditions of the enrichment culture caused a change in the microbial community composition of the inoculated activated sludge. Dominant DGGE bands in the enrichment culture sample were affiliated with the classes β-Proteobacteria, Bacteroidetes, and Spirochaetes. Further investigation is warranted to reveal the metabolic roles of the dominant populations in the ClO4 degradation process, along with their isolation.

Safety of Nano-sized Bee Pollen in both In-vitro and In-vivo Models (생체 외 및 생체 내 실험조건에서 나노화 벌 화분의 안전성 규명)

  • Pyeon, Hae-In;So, Soojeong;Bak, Jia;Lee, Seunghyun;Lee, Seungmin;Suh, Hwa-Jin;Lim, Je-Oh;Kim, Jung-Woo;Kim, Sun Youn;Lee, Se Ra;Lee, Yong Hyun;Chung, Il Kyung;Choi, Yun-Sik
    • Journal of Life Science
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    • v.28 no.5
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    • pp.605-614
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    • 2018
  • Bee pollen has an outer wall which is resistant to both acidic and basic solutions and even the digestive enzymes in the gastrointestinal tract. Therefore, the oral bioavailability of bee pollen is only 10-15%. A previous study reported on wet-grinding technology which increased the extraction of active ingredients from bee pollen by 11 times. This study was designed to investigate the safety of wet-ground bee pollen. First, a single dose of wet-ground bee pollen was tested in both rats and beagle dogs at dosages of 5, 10, and 20 g/kg and 1.5, 3, and 6 g/kg, respectively. In rats, compound-colored stools were found in those administered 10 g/kg or more of wet-ground bee pollen. In beagle dogs, 6 g/kg of wet-ground bee pollen induced diarrhea in one male for four hours. However, no obvious clinical signs were found through the end of the experiment in rats and beagle dogs. In addition, no histological abnormality was found in all animals. The data indicates that a single dose of up to 20 g/kg of wet-ground bee pollen is safe. Next, the genetic toxicity of nano-sized bee pollen was tested. This study employed a bacterial reverse mutation test, a micronucleus assay, and a chromosomal aberration assay. In the micronucleus assay, there was no genetic toxicity up to the dosage of 2 g/kg. There was also no genetic toxicity in the bacterial reverse mutation test and chromosomal aberration assay. This data provides important information in developing nano-sized bee pollen into more advanced functional foods and herbal medicines.

Evaluation of Filtration and Backwash Efficiency of Non-point Source Pollution Reduction Facility (장치형 비점오염원 저감시설의 여과 및 역세 효율 평가)

  • Yun, Sangleen;Lee, Yong-Jae;Ahn, Jae-Hwan;Choi, Won-Suk;Lee, Jungwoo;Oh, Hye-Cheol;Kim, Seog-Ku
    • Journal of Korean Society of Environmental Engineers
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    • v.39 no.12
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    • pp.664-671
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    • 2017
  • Non-point source pollution is the emission source that unspecifically releases pollutants to water system from unspecific places such as cities, agricultural lands, mountains, and construction sites and its discharge path is not easily identified. Also, it is difficult to design and manage the reduction facilities for the emission quantity is primarily affected from weather conditions like rainfall. Since 2006, the significance of non-point source pollution reduction has been grown in Republic of Korea and this reinforces needs for the installation of reduction facilities. However, because the standards for the installation details and reduction efficiency are not clarified by law, people are preferring technologies that do not require particular maintenance and high expenses. The purpose of this study is to examine and maintain the efficiency of non-point source pollutants reduction facility which uses expended polypropylene as a media. The higher the depth of the media, the less range of variations in the reduction efficiency was observed and the final efficiency was also increased. When the media depth was 60 cm, the average reduction efficiency was 94% and 90% where linear velocities were 10 m/hr and 20 m/hr respectively. The results from 180 minutes operation in 10 m/hr and 20 m/hr of linear velocities were slightly different in head loss changes which were caused by media depth variations. The backwash experiments which were conducted in triplicate showed the reduction efficiency decreased as the time went on because of the media clogging. However, it was found that after the backwashing the reduction efficiency was increased as effective as the efficiency of the initial filtration.

Scaling up Hydrothermal Synthesis of Na-A Type Zeolite from Natural Siliceous Mudstone and Its Heavy Metal Adsorption Behavior (규질 이암으로부터 Na-A형 제올라이트의 scale-up 수열합성 및 중금속흡착)

  • Bae, In-Kook;Jang, Young-Nam;Shin, Hee-Young;Chae, Soo-Chun;Ryu, Kyoung-Won
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.4
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    • pp.341-347
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    • 2008
  • The feasibility of commercializing the hydrothermal synthesis of Na-A type zeolite from siliceous mudstone has been conducted using a 50-liter bench-scale autoclave and the application of the zeolite as an environmental remediation agent. Siliceous mudstone, which is widely distributed around the Pohang area, was adopted as a precursor. The siliceous mudstone is favorable for the synthesis of zeolite because it contains 70.7% $SiO_2$ and 10.0% $Al_2O_3$, which are major ingredient of zeolite formation. The synthesis of zeolite was carried out under the following conditions that had been obtained from the previous laboratory-scale tests: 10hr reaction time, $80^{\circ}C$ reaction temperature, $Na_2O/SiO_2$ ratio = 0.6, $SiO_2/Al_2O_3$ ratio = 2.0 and $H_2O/Na_2O$ ratio= 98.6. The crystallinity and morphology of the zeolite formed were similar to those obtained from the laboratory-scale tests. The recovery and cation exchange ion capacity were 95% and 215 cmol/kg, respectively, which are slightly higher than those obtained in laboratory scale tests. To examine the feasibility of the zeolite as an environmental remediation agent, experiments for heavy metal adsorption to zeolite were conducted. Its removal efficiencies of heavy metals in simulated waste solutions decreased in the following sequences: Pb > Cd > Cu = Zn > Mn. In a solution of 1500 mg/L total impurity metals, the removal efficiencies for these impurity metals were near completion (> 99%) except for Mn whose efficiency was 98%. Therefore, the synthetic Na-A type zeolite was proven to be a strong absorbent effective for removing heavy metals.

Relationship between iron deficiency anemia and febrile convulsion in infants (영아에서 철결핍 빈혈과 열성경련과의 상관관계)

  • Jun, Youn Soo;Bang, Ho Il;Yu, Seung Taek;Shin, Sae Ron;Choi, Du Young
    • Clinical and Experimental Pediatrics
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    • v.53 no.3
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    • pp.392-396
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    • 2010
  • Purpose : The association between iron deficiency anemia and febrile convulsion in infants has been examined in several studies with conflicting results. Therefore, the authors aimed to evaluate the precise relationship involved. Methods : In this case-control study, the authors assessed 100 children with a diagnosis of febrile convulsion, aged between 9 months and 2 years, during January 2007 to July 2009. The control group consisted of 100 febrile children without convulsion; controls were closely matched to the cases by age, gender, and underlying disease. Results : The mean ages of the febrile convulsion and control group were $16.3{\pm}7.4$ and $15.8{\pm}6.1$ months, respectively, and the two groups had no differences in clinical features. Iron deficiency anemia (Hb <10.5 gm/dL) was more frequent in the febrile convulsion group than in the control group, although there was no statistical significance. Unexpectably, the RDW (red blood cell distribution width) was significantly lower and the MCNC (mean corpuscular hemoglobin concentration) was significantly higher among seizure cases than among the controls (P <0.05). There is no statistical difference between simple and complex febrile groups in the clinical and laboratory profiles. On multiple logistic regression analysis, iron deficiency anemia was more frequent, but the RDW was lower, among the cases with febrile convulsion, compared with the controls. Conclusions : Our study suggests that the iron deficiency anemia is associated with febrile convulsion, and screening for iron deficiency anemia should be considered in children with febrile convulsions.