• Title/Summary/Keyword: 요소분리

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Two Novel Families of Short Interspersed Repetitive Elements from the Mud Loach (Misgurnus mizolepis)

  • Lim, Hak-Seob;Kim, Moo-Sang;Kim, Ok-Soon;Kim, Ji-Yeon;Choi, Young-Mi;Ahn, Sang Jung;Lee, Hyung-Ho
    • Journal of Marine Bioscience and Biotechnology
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    • v.1 no.3
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    • pp.186-192
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    • 2006
  • Short interspersed repetitive elements (SINEs) are dispersed throughout eukaryotic genomes. These SINEs have been shown to be excellent phylogenetic markers for the closed related species. In this report, we isolated two novel families of SINEs from the mud loach. The two SINE families, mlSINE-L and mlSINE-S, have genomic lengths of about 410bp and 270bp, respectively. 5' and 3' ends of the SINE families are well conserved and highly homologous to each of corresponding ends of RSg-1 and SmaI SINEs. Phylogenetic analysis shows that mlSINEs are unique to the mud loach. A dot blot hybridization experiment shows that mlSINE-L has an estimated copy number of $1{\times}10^3$ per $2{\times}10^9bp$ (2.8 pg) and is more frequently distributed at nuclear matrix attachment regions (MARs) than loop DNAs. The result suggests that mlSINEs may preferentially integrate in or near MARs.

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Characterization of the bacteriophage P4 sid+ derivative overcoming P2sir-associated helper inefficiency through DNA conformational adaptation (DNA 형태 적응을 거쳐 P2sir-관련 도움파지 비효율성을 극복하는 박테리오파지 P4 sid+ 유도체 정성 연구)

  • Kim, Kyoung-Jin
    • Korean Journal of Microbiology
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    • v.52 no.1
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    • pp.120-124
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    • 2016
  • A certain size of DNA (28-29 kb long) to be packaged into P2-size head and the mutation in sid gene of bacteriophage P4 are the major factors to overcome "P2 sir-associated helper inefficiency". To clarify whether the presence of sid mutation is essential to overcome "P2 sir-associated helper inefficiency" or not, we tested the P4 derivative, P4 delRI::kmr, which is $sid^+$ and whose genome size supposed to be 28.5 kb long in the case of being packaged into $P2_{sir3}$-sized large head. As P4 delRI::kmr showed the low EOP with P2 sir3 lysogen, P4 delRI::kmr phage stock was prepared in P2 sir3 lysogen host to increase the EOP with P2 sir3 lysogen. Through this process, P4 delRI::kmr had been adapted for P2 sir3 lysogen. With a CsCl buoyant equilibrium density gradient experiment and gel electrophoresis of the isolated DNA, it was evident that the adaptation of P4 delRI::kmr for P2 sir3 lysogen was caused by the conformational change of DNA to be packaged into large head. The burst size determination experiments with P4 delRI::kmr phage stock adapted for P2 sir3 lysogen and normal P4 delRI::kmr phage stock showed that not the sid mutation but the size of DNA to be packaged (28-29 kb long) was essential to overcome "P2 sir-associated helper inefficiency".

A Study on the Interfacial Bonding between AlN Ceramics and Metals: II. Effect of Mo Interlayer on the Residual Stress of AlN/Cu Joint (AlN 세라믹스와 금속간 계면접합에 관한 연구: II. AlN/Cu 접합체의 잔류응력에 미치는 Mo 중간재의 영향)

  • Park, Sung-Gye;Kim, Ji-Soon;You, Hee;Yum, Young-Jin;Kwon, Young-Soon
    • Korean Journal of Materials Research
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    • v.9 no.10
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    • pp.970-977
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    • 1999
  • Effect of Mo interlayer on the relaxation of residual stress in AlN/Cu pint bonded by active-metal brazing method was investigated. The stress analyses by finite-element-method, the measurement of pint strength and the observation of fracture surface were carried out and their results were compared with each other. From the results of stress analysis it is confirmed that a Mo interlayer led to a shift of maximum stress concentration site from AlN/insert-metal interface$\rightarro$ insert-metal/Mo$\rightarro$Mo interlayer. Additionally, with increase of the Mo interlayer thickness the stress concentration with tensile component was separately built both at the interface of Cu/Mo and AlN/Mo. whereby the residual stress in the free surface of AlN close to the bonded interface was drastically reduced. The AlN/Mo/Cu pints with Mo interlayer thickness of above 400$\mu\textrm{m}$ showed the strengths higher than 200 MPa. upto max. 275 MPa, while the AlN/Cu pint only max. 52 MPa.

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Efficient Plant Regeneration from Mesophyll Protoplast of Arabidopsis thaliana and Morphological Characterization of Regenerants (애기장대 (Arabidopsis thaliana)의 엽육원형질체로부터 효율적인 식물체 재분화와 이들의 형태적 특성)

  • 김명덕;김준철;진창덕;임창진;한태진
    • Korean Journal of Plant Tissue Culture
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    • v.26 no.2
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    • pp.127-132
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    • 1999
  • Protoplasts were isolated from the leaf mesophyll tissue of in vitro 4-weeks-old Arabidopsis thaliana and cultured in MS liquid medium supplemented with 2.0 mg/L NAA, 0.5 mg/L BAP and 9% mannitol in the dark at $25^{\circ}C$. When protoplast-derived microcolonies were dehydrated, the frequency of callus induction enhanced approximately 7-fold higher compared with non-dehydrated microcolonies in CP medium. Fifty callus lines were selected from dehydrated microcolonies. Shoots were efficiently initiated from the green spots of the selected shoot forming calli cultured on MS regeneration medium supplemented with 0.05 mg/L IAA, 7.0 mg/L 2-iP and 30 g/L sucrose under continous illumination for 4 weeks. Shoot regeneration frequencies (calli regenerating at least one shoot) were 3.5%~56%. Histological observations of shoot forming callus revealed that tracheary elements initiated from inner compact cells, and that meristemoids developed to shoot primordia and shoots. Roots were induced from these regenerating shoots on MS medium without phytohormones. These regenerants were successfully transplanted into potting soil. Morphological characterization of 50 protoplast-derived plants showed that the frequency of normal type was 78%.

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A Study on Green Library Construction Status and Awareness (녹색도서관 구축 현황 및 인식조사 연구)

  • Hong, Suji;Noh, Younghee
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.25 no.4
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    • pp.79-108
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    • 2014
  • The purpose of this study was to research instances of green library construction and recognition in order to increase awareness of green libraries. To this end, we investigated the green library's outline and green building, evaluated cases of G-SEED certified libraries, and surveyed the employees at the 16 different G-SEED certified libraries. Results showed that the employees' knowledge of green libraries and the green certification system was low, whereas their interest and needs regarding the green library concept were very high. Second, the respondents were able to recognize as a whole the factors of green library construction based on the evaluation items for G-SEED and place particular emphasis on 'recyclable resources & recycling bins.' However, only a few recognized 'water reclamation/reuse system establishment' as a green library factor. Third, the respondents largely agreed upon an evaluation of items on the suitability of G-SEED, and their ranked reasons for build a green library were preventing environmental pollution, energy-saving, environment, ecology, and indoor environmental factors. Fourth, a lack of 'awareness about the concept of the green library' was thought to most affect the awareness of difficulties in green library construction, and the respondents agreed with the need for 'library image enhancement' to better manage expectations of the green library.

Role and Process of Abduction in Elementary School Students' Generation of Hypotheses concerning Vapor Condensation (수증기 응결에 관한 초등학생들의 가설 생성에서 귀추의 역할과 과정)

  • Shim, Hae-Sook;Jeong, Jin-Su;Park, Kuk-Tae;Kwon, Yong-Ju
    • Journal of the Korean earth science society
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    • v.24 no.4
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    • pp.250-257
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    • 2003
  • The purpose of this study was to test the hypotheses that student's abductive reasoning ability plays an important role in hypothesis-generating about vapor condensation, and student's hypothesis-generating requires their causal explicans as well as experience. To test the hypotheses, the instruments of hypothesis-generation, prior knowledge, and experience with vapor condensation were developed and administered to 6th grade students. This study found that 72 subjects among 89 students who had prior knowledge about vapor condensation failed to apply their prior knowledge to hypothesis-generating about the vapor condensation. This result showed that the students' failure in hypothesis-generating was related to their deficiency in abductive reasoning ability. In addition, this study showed that 54 subjects among 56 students who had experience with vapor condensation also failed to generate hypotheses. This result supported that student's causal explanations were separated from their experience. Therefore, this study suggests that science education should include the teaching of abductive reasoning skills for developing student's hypothesis-generating skills.

Analysis and Comparison of Views of Nature Between East Asia and the Western World and its Meaning (동아시아·서양의 자연의 의미와 자연관 비교 분석)

  • Lee, Yumi;Son, Yeon-A
    • Journal of The Korean Association For Science Education
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    • v.36 no.3
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    • pp.485-498
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    • 2016
  • In this study, the views and the meaning of nature between the Western world and East Asia were compared through literature analysis. In the West, it is recognized that nature and human beings are separate. Nature is understood as regular and rational. They, therefore, take the view of particle and mechanical theory. In East Asia, it is thought that nature and humans interact with each other, and take an attitude of compromise and tolerance. Since nature is recognized as an ever-changing being, they, therefore, take the position of wave theory. Scientific knowledge and concepts are accepted depending on the personal view of nature. In Korea, science education follows the view of modern western science without considering the personal pattern of cognition, though students can have various views of nature. The attitude is needed regarding the various viewpoints as rich resources in science and science education.

A prosodic cue representing scopes of wh-phrases in Korean: Focusing on North Gyeongsang Korean (한국어 의문사 작용역을 나타내는 운율 단서: 경북 방언을 중심으로)

  • Yun, Weonhee;Kim, Ki-tae;Park, Sunwoo
    • Phonetics and Speech Sciences
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    • v.12 no.3
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    • pp.41-53
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    • 2020
  • A wh-phrase in an embedded sentence may have either an embedded or a matrix scope. Interpretation of a wh-phrase with a matrix scope has tended to be syntactically unacceptable unless the sentence reads with a wh-intonation. Previous studies have found two differences in prosodic characteristics between sentences with matrix and embedded scopes. Firstly, peak F0s in wh-phrases produced with an F0 compression wh-intonation are higher than those in indirect questions, and peak F0s in matrix verbs are lower than those in sentences with embedded scope. Secondly, a substantial F0 drop is found at the end of embedded sentences in indirect questions, whereas no F0 reduction at the same point is noticed in sentences with a matrix scope produced with a high plateau wh-intonation. However, these characteristics were not found in our experiment. This showed that a more compelling difference exists in the values obtained from subtraction between the peak F0s of each word (or a word plus an ending or case marker) and the F0s at the end of the word. Specifically, the gap between the peak F0 in a word composed with an embedded verb and the F0 at the end of the word, which is a complementizer in Korean, is large in embedded wh-scope sentences and low in matrix wh-scope sentences.

An Expanded Real-Time Scheduler Model for Supporting Aperiodic Task Servers (비주기적 태스크 서버들을 지원하기 위한 확장된 실시간 스케줄러 모델)

  • Shim, Jae-Hong;Kim, Yeong-Il;Choi, Hyung-Hee;Jung, Gi-Hyun;Yoo, Hae-Young
    • The KIPS Transactions:PartA
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    • v.8A no.1
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    • pp.16-26
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    • 2001
  • This paper proposes an extended scheduler model that is an extension of the existing model proposed already in [4, 5], which consists of upper layer task scheduler and lower layer scheduling framework. However, in order to support aperiodic task scheduling, the task scheduler has been divided into two parts, such as periodic task control component and aperiodic task control component. Thus, the proposed model can support various bandwidth-preserving servers that can service aperiodic tasks. The model distinctly separates a classic monolithic kernel scheduler into several kernel components according to their functionality. This enables system developers to implement a new scheduling algorithm or aperiodic task server independent of complex low kernel mechanism, and reconfigure the system at need. In Real-Time Linux [6], we implemented the proposed scheduling framework representative scheduling algorithms, and server bandwidth-preserving servers on purpose to test. Throughout these implementations, we confirmed that a new algorithm or server could be developed independently without updates of complex low kernel modules. In order to verify efficiency of the proposed model, we measured the performance of several aperiodic task servers. The results showed this the performance of model, which even consisted of two hierarchical components and several modules, didnt have such high run-time overhead, and could efficiently support reconfiguration and scheduler development.

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Finding Frequent Itemsets Over Data Streams in Confined Memory Space (한정된 메모리 공간에서 데이터 스트림의 빈발항목 최적화 방법)

  • Kim, Min-Jung;Shin, Se-Jung;Lee, Won-Suk
    • The KIPS Transactions:PartD
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    • v.15D no.6
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    • pp.741-754
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    • 2008
  • Due to the characteristics of a data stream, it is very important to confine the memory usage of a data mining process regardless of the amount of information generated in the data stream. For this purpose, this paper proposes the Prime pattern tree(PPT) for finding frequent itemsets over data streams with using the confined memory space. Unlike a prefix tree, a node of a PPT can maintain the information necessary to estimate the current supports of several itemsets together. The length of items in a prime pattern can be reduced the total number of nodes and controlled by split_delta $S_{\delta}$. The size and the accuracy of the PPT is determined by $S_{\delta}$. The accuracy is better as the value of $S_{\delta}$ is smaller since the value of $S_{\delta}$ is large, many itemsets are estimated their frequencies. So it is important to consider trade-off between the size of a PPT and the accuracy of the mining result. Based on this characteristic, the size and the accuracy of the PPT can be flexibly controlled by merging or splitting nodes in a mining process. For finding all frequent itemsets over the data stream, this paper proposes a PPT to replace the role of a prefix tree in the estDec method which was proposed as a previous work. It is efficient to optimize the memory usage for finding frequent itemsets over a data stream in confined memory space. Finally, the performance of the proposed method is analyzed by a series of experiments to identify its various characteristics.