• Title/Summary/Keyword: u-Korea

Search Result 14,653, Processing Time 0.049 seconds

Influence of Iron Phases on Microbial U(VI) Reduction

  • Lee, Seung-Yeop;Baik, Min-Hoon;Lee, Min-Hee;Lee, Young-Boo;Lee, Yong-Jae
    • Journal of Soil and Groundwater Environment
    • /
    • v.16 no.6
    • /
    • pp.58-65
    • /
    • 2011
  • The bacterial uranium(VI) reduction and its resultant low solubility make this process an attractive option for removing U from groundwater. An impact of aqueous suspending iron phase, which is redox sensitive and ubiquitous in subsurface groundwater, on the U(VI) bioreduction by Shewanella putrefaciens CN32 was investigated. In our batch experiment, the U(VI) concentration ($5{\times}10^5M$) gradually decreased to a non-detectable level during the microbial respiration. However, when Fe(III) phase was suspended in solution, bioreduction of U(VI) was significantly suppressed due to a preferred reduction of Fe(III) instead of U(VI). This shows that the suspending amorphous Fe(III) phase can be a strong inhibitor to the U(VI) bioreduction. On the contrary, when iron was present as a soluble Fe(II) in the solution, the U(VI) removal was largely enhanced. The microbially-catalyzed U(VI) reduction resulted in an accumulation of solid-type U particles in and around the cells. Electron elemental investigations for the precipitates show that some background cations such as Ca and P were favorably coprecipitated with U. This implies that aqueous U tends to be stabilized by complexing with Ca or P ions, which easily diffuse and coprecipitate with U in and around the microbial cell.

Reliability Model for u-Health SW's BMT (u-Health SW의 BMT를 위한 신뢰성 모델)

  • Chung, Sam-Sool;Yang, Hae-Sool
    • The Journal of the Korea Contents Association
    • /
    • v.10 no.5
    • /
    • pp.80-89
    • /
    • 2010
  • u-Health refers to "Always, ubiquitously" prevention against disease, diagnosis, medical treatment service that can receive treatment even if patient does not visit hospital as abbreviated word of ubiquitous and health. U-Health transmits in individual's living body sign and measuring of health information and health information system that is consisted of process of analysis and feedback transmiting and measure individual's living body signal and health information and health proprietary company or medical institution operates. If analyze pattern to information that health information system is transmited, health care officer or chief physician means that offer healthcare and medical treatment service to remote about target customer. Wish to present authoritativeness model for u-Health's inside and outside of the country same native place and u-Health's BMT in this research.

A Methodology for Assessing the Level of U-Transformation of Ubiquitous Services

  • Kwon, Oh-Byung;Kim, Ji-Hoon;Choi, Keun-Ho
    • Proceedings of the Korea Association of Information Systems Conference
    • /
    • 2005.12a
    • /
    • pp.359-366
    • /
    • 2005
  • As the ubiquitous computing technology (uT) is prevailing, applying uT is more likely to transform the legacy way of doing business to a new way with the goals of ubiquitous computing: strategic use of information resources by using them everywhere, every time, with any devices for any services. These opportunities naturally require the provision to assess the degree of the transformation from the legacy IT-based e-business to the uT-based business. However, research about assessing the degree of u-transformation has been still very few. Moreover, even deciding what is ubiquitous or not is obscure. Hence, this paper aims to propose the methodology for assessing the degree of u-transformation oriented by the teleology of ubiquitous service, which intends to fully make use of uT in creating new business of next generation. Through the literature review, we developed the methodology to check whether the provided service is ubiquitous or not based on the capabilities that technologies have. and then, the methodology developed to assess the technical requirements that the uT should have when the transformation is considered through the focus group interview based on the literature review of the capability. A two-layered approach is introduced to assess not only the level of ubiquity but also the degree of u-transformation.

  • PDF

A Study on the Demand for Ubiquitous Computing Services (유비쿼터스 서비스 수요에 관한 연구)

  • KIm, Ji-Soo;Kim, Jong-Myoung;Lee, Tae-Soo
    • Journal of the Korea Society of Computer and Information
    • /
    • v.12 no.4
    • /
    • pp.103-110
    • /
    • 2007
  • Ubiquitous computing is a vogue word, and its service is very popular in Korea. However, present ubiquitous service(u-Service) is thought to be more oriented to the provider's point of view, not the consumer's. To complement this problem, an online survey was performed for internet users, which consists of 24 single choice questions on six fields such as transportation, healthcare, environment/city-management, culture/education, administration, and industry. 2463 people joined the survey, who were grouped according to their age, resident region, level of education, and sex. Each group's demand for specific field of u-Service was examined. General level of demand was higher in case of the elderly and male than the younger and female for overall u-Service.

  • PDF

A Study on the Domestic Technical Regulation of Low Power u-IT Equipments (저전력 u-IT 기기의 국내 기술 기준에 관한 연구)

  • Ra, Yoo-Chan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.5
    • /
    • pp.2249-2253
    • /
    • 2011
  • This paper analyzed the problems of the Korean output regulation in the relevant band through an analytic comparison of the current trend of each country and their standard values concerning the technical standard of low power u-IT equipments. In connection with the standard value of technical values of each country, which has been proposed in the registration of the appropriate electric wave, the paper aims to propose the standard value that could actually be introduced for suitable low power u-IT installations in Korea. Provided that the Korean standard may be upgraded based on the tolerances of technical standards proposed in this paper, this is expected to be committed to the distribution and advancement of low power u-IT equipments; and further, it is anticipated to be prepared with competitiveness not only in the Korean communications market, but also in the international communications market.

Evaluation of co- and Sequential Separation for Tc, Np and U by a $(TBP-TOA)/n-dodecane-HNO_3$ Extraction System ($(TBP-TOA)/n-dodecane-HNO_3$ 추출 계에 의한 Tc, Np, U의 공추출 및 순차분리 평가)

  • Lee, Eil-Hee;Lim, Jae-Kwan;Chung, Dong-Yong;Yang, Han-Beom;Kim, Kwang-Wook
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.5 no.2
    • /
    • pp.133-143
    • /
    • 2007
  • This study was performed to evaluate the co- and sequential separation of Tc, Np and U from the simulated multi-component HLW solution by a TBP (tributyl phosphate)-TOA (tri- octyl amine)/NDD $(n-dodecane)-HNO_3$ extraction system. An optimal condition of (30% TBP-0.5% TOA)/NDD-1 M $HNO_3$ was selected by taking account of a prevention of the 3rd phase and effects of concentration of TBP, TOA and nitric acid on the co-extraction of Tc, Np and U. In that condition, the extraction yields were 81% (Tc), 85% (Np), less than 9% (Am and RE elements), about 8% (Pd), and less than 5% (other elements) so that the system developed for the co-extraction of Tc, Np and U was proved to be available. For that, however, more than 99% of Zr was found to be pre-removed. The co-extracted Tc, Np and U were sequentially separated in order of Tc(stripping agent : 5 M $HNO_3$)${\rightarrow}Np$ by reductive stripping (reductive-stripping agent : 0.1 M AHA)${\rightarrow}U$ (stripping agent : 0.01 M $HNO_3$), and then their separation factors were evaluated. At these conditions, 95% of Tc, 98% of Np and 99% of U could be recovered in each step.

  • PDF

An Operational Analysis of Denfense Expenditures (국방비의 O.R.적 분석)

  • Won, Un-Sang
    • Journal of the military operations research society of Korea
    • /
    • v.3 no.2
    • /
    • pp.91-101
    • /
    • 1977
  • The recent issue on the withdrawal of U.S. Forces from Korea Suggests an Urgency of Self Defense of Korea. The expected huge defense budget and her armed forces create a need for an operational analysis. It is shown through a statistical analysis what some of the opportunity costs of defense spending have been. Some evidences about what some of the economy sacrifice if defense spending rises have been analyzed to provide executive departments with a quantitative basis for decisions. The Korea-U.S. alliance is discussed in view of the developmental effects of U.S. aids and deterrent effects of U.S.F.K.

  • PDF

Design of U-School Framework Based on User-Centric Scenario (사용자 중심 시나리오에 따른 U-스풀 프레임워크 설계)

  • Hong, Myoung-Woo;Cho, Dae-Jae
    • The Journal of the Korea Contents Association
    • /
    • v.7 no.12
    • /
    • pp.283-291
    • /
    • 2007
  • In the age of ubiquitous computing, computer systems will be seamlessly integrated into our everyday life, providing services and information to us in an anywhere, anytime fashion. This ubiquitous computing can be used for developing a ubiquitous learning (U-learning). In this paper, we present a framework for U-school in which ubiquitous computing technologies are applied to advance the existing ERSS (Korea's Educational Resources Sharing System). Our framework applies mobile, sensor, and context-aware technologies to the existing ERSS. This framework presents a user-centric learning environment, using user-centric scenario. The U-school with context-aware services therefore can lead to the just-in-time learning or learner-led learning based on dynamic contexts acquired from learners, teachers and computing entities.

Taxonomic Identities and Distribution of Utricularia japonica and U. tenuicaulis in Korea (한국산 통발(Utricularia japonica)과 참통발(U. tenuicaulis)의 분류학적 실체 및 분포)

  • Na, Sung Tae;Choi, Hong-Keun;Kim, Young Dong;Shin, Hyunchur
    • Korean Journal of Plant Taxonomy
    • /
    • v.38 no.2
    • /
    • pp.111-120
    • /
    • 2008
  • Taxonomic identities of Utricularia japonica and U. tenuicaulis were examined. Utricularia japonica was differed from U. tenuicaulis by having a scape narrower than the stem, rather sparsely arranged leaves, and more or less oblong leaves. Utricularia japonica has been known to occur widely in Korea due to the misidentification of U. tenuicaulis, which is distributed widely in southern and middle Korea. However, only one population of U. japonica was found in Chunjin Lake, near Kosung-gun, Kwangwon-Do, in Korea.

An Experimental Study on the Sorption of U(VI) onto Granite

  • Min-Hoon Baik;Pil-Soo Hahn
    • Nuclear Engineering and Technology
    • /
    • v.34 no.5
    • /
    • pp.445-454
    • /
    • 2002
  • The sorption of U(Vl) on a domestic granite is studied as a function of experimental conditions such as contact time, solution-solid ratio, ionic strength, and pH using a batch procedure. The distribution coefficients, $K_{d}$'s, of U(VI) are about 1-100mL/g depending on the experimental conditions. The sorption of U(VI) onto granite particles is greatly dependent upon the contact time, solution-solid ratio, and pH, but very little is dependent on the ionic strength. It is noticed that an U(VI)-carbonate ternary surface complex can be formed in the neutral range of pH. In the alkaline range of pH above 7, U(VI) sorption onto granite particles is greatly decreased due to the formation of anionic U(VI)-carbonate aqueous complexes.s.