• 제목/요약/키워드: evolution status

검색결과 194건 처리시간 0.026초

Taxonomic Status of Siberian Flying Squirrel from Korea (Pteromys volans aluco Thomas 1907)

  • Koh, Hung-Sun;Jin, Yi;Yang, Beong-Guk;Lee, Bae-Keun;Heo, Seon-Wook;Jang, Kyung-Hee
    • Animal Systematics, Evolution and Diversity
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    • 제24권2호
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    • pp.169-172
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    • 2008
  • Sequences of mitochondrial DNA (mtDNA) cytochrome b gene (1,140 bp) and control region (803 bp) of Siberian flying squirrels from Korea (Pteromys volans aluco) and Mt. Changbai of northeast China (P. v. arsenjevi) were obtained to reexamine the taxonomic status of the Korean subspecies. In the cytochrome b gene, six haplotypes of P. v. aluco formed a clade with six haplotypes of P. v. arsenjevi, and in control region, seven haplotypes of P. v. aluco formed a clade with six haplotypes of P. v. arsenjevi. Furthermore, six haplotypes of cytochrome b gene of P. v. aluco from this study formed a clade with four haplotypes of P. v. arsenjevi in far-east Russia obtained from GenBank. We also investigated the research papers previously published that reported the length of tail vertebrae of P. volans, and found that the length was not sufficiently large as to be a key character of P. v. aluco. This result is not consistent with morphological description for its haplotype. Therefore, we conclude that P. v. aluco from Korea might possibly be a synonym of P. v. arsenjevi from northeast China and nearby Russia.

EVOLUTION OF NUCLEAR FUEL MANAGEMENT AND REACTOR OPERATIONAL AID TOOLS

  • TURINSKY PAUL J.;KELLER PAUL M.;ABDEL-KHALIK HANY S.
    • Nuclear Engineering and Technology
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    • 제37권1호
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    • pp.79-90
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    • 2005
  • In this paper are reviewed the current status of nuclear fuel management and reactor operational aid tools. In addition, we indicate deficiencies in current capabilities and what future research is judged warranted. For the nuclear fuel management review the focus is on light water reactors and the utilization of stochastic optimization methods applied to the lattice, fuel bundle, core loading pattern, and for BWRs the control rod pattern/core flow design decision making problems. Significant progress in addressing separately each of these design problems on a single cycle basis is noted; however, the outstanding challenge of addressing the integrated design problem over multiple cycles under conditions of uncertainty remains to be addressed. For the reactor operational aid tools review the focus is on core simulators, used to both process core instrumentation signals and as an operator aid to predict future core behaviors under various operational strategies. After briefly reviewing the current status of capabilities, a more in depth review of adaptive core simulation capabilities, where core simulator input data are adjusted within their known uncertainties to improved agreement between prediction and measurement, is presented. This is done in support of the belief that further development of adaptive core simulation capabilities is required to further significantly advance the utility of core simulators in support of reactor operational aid tools.

Vortex-induced vibration characteristics of multi-mode and spanwise waveform about flexible pipe subject to shear flow

  • Bao, Jian;Chen, Zheng-Shou
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제13권1호
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    • pp.163-177
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    • 2021
  • Numerical simulations of the Vortex-Induced Vibration (VIV) about a large-scale flexible pipe subject to shear flow were carried out in this paper. Efficiency verification was performed firstly, validating that the proposed fluid-structure interaction solution strategy is competent in predicting the VIV response. Then, the VIV characteristics related to multi-mode and spanwise hybrid waveform about the flexible pipe attributed to shear flow were investigated. When inflow velocity rises, higher vibration modes are apt to be excited, and the spanwise waveform easily convertes from a standing-wave-dominated status to a hybrid standing-traveling wave status. The multi-mode or even multiple-dominant-mode is prone to occur, that is, the dominant mode is often followed by several apparent subordinate modes with considerable vibration energy. Hence, the shedding frequencies no longer obey Strouhal law, and vibration trajectories become intricate. According to the motion analysis concerning the coupled cross-flow and in-line vibrations, as well as the corresponding wake patterns, a tight coupling interaction exists between the structural deformation and the wake flow behind the flexible pipe. In addition, the evolution of the vortex tube along the pipe span and a strong 3D effect are observed due to the slenderness of the flexible pipe and the variability of the vortex shedding attributed to the shear flow.

Status of KASI's Contribution to SPHEREx

  • Jeong, Woong-Seob;Yang, Yujin;Park, Sung-Joon;Pyo, Jeonghyun;Jo, Youngsoo;Kim, Il-Joong;Bang, Seungcheol;Lee, Bomee
    • 천문학회보
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    • 제46권2호
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    • pp.53.1-53.1
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    • 2021
  • The KASI team are participating in the NASA MIDEX mission (PI Institute: Caltech), the all-sky infrared spectro-photometric surveyor SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer). The SPHEREx will provide us the first all-sky infrared spectro-photometric data set to probe the origin of our Universe, to explore the origin and evolution of galaxies, and to explore whether planets around other stars could harbor life. After the project PDR (Preliminary Design Review) was successfully passed on the last September, the fabrication of flight hardware is in progress. As an international partner, KASI deeply involved in all fields of projects, i.e., the development of calibration facility, the construction of data reduction modules and the science studies for the SPHEREx. After finishing the fabrication and test of calibration facility for the SPHEREx in this year, it will be delivered to Caltech. Here, we report the status of the SPHEREx project and the progress in the Korean participation.

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전자종이 디스플레이 기반 ESL의 시장현황 및 분석 (Market Status and Analysis of ESL Based on Electronic Paper Display)

  • 김영조
    • 한국산업융합학회 논문집
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    • 제27권1호
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    • pp.17-24
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    • 2024
  • Recently, retail technology has been developed by the rapid evolution of e-commerce and a representative example is ESL technology. In this study, we investigate ESL technology, market status and forecasts, and analyze the competitive structure between relational companies. Market analysis refers to data from market reports of Marketsandmarkets and Research, and internet media. In ESL, the display field is predicted to account for 43% of the total market in 2026, and is converting from LCD to electronic paper. The segmented type is becoming more advanced into the full-graphic type, and CAGR of 18.7% for 3-7 inches and 20.6% for 7-10 inches is predicted. The demand for ESL is greatest in North America and Europe, but CAGR is the highest in the Asia-Pacific region at 19.1%. Since ESL technology has a lot of overlap with semiconductor and display technology, the Asia-Pacific region is relatively advantageous, and this has led to rapid growth of domestic companies. However, it is expected that competition from European companies that are actually owned by Chinese companies will increase in the future, so continuous technological development and new market development are necessary.

Determining the Specific Status of Korean Collared Scops Owls

  • Hong, Yoon Jee;Kim, Young Jun;Murata, Koichi;Lee, Hang;Min, Mi-Sook
    • Animal Systematics, Evolution and Diversity
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    • 제29권2호
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    • pp.136-143
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    • 2013
  • The collared scops owl that occurs in Korea is a protected species but its exact specific status has been questioned. To resolve the species status, a molecular phylogenetic analysis was conducted using two fragments of mitochondrial DNA, cytochrome b (cyt b, 891 bp) and NADH dehydrogenase subunit 2 (ND2, 627 bp) genes. Phylogenetic trees of cyt b revealed that all Korean specimens formed a monophyletic group with Japanese scops owl Otus semitorques with very low sequence divergence (d=0.008). We obtained a similar ND2 tree as well (d=0.003); however, the genetic distance between Korean individuals and O. lempiji from GenBank (AJ004026-7, EU348987, and EU601036) was very high and sufficient enough to separate them as species (cyt b, d=0.118; ND2, d=0.113). We also found that Korean species showed high differentiation from O. bakkamoena (AJ004018-20 and EU601034; cyt b, d=0.106; ND2, d=0.113) and O. lettia (EU601109 and EU601033, cyt b, d=0.110; ND2, d=0.117) as well. Therefore, we suggest that the Korean collared scops owl should be designated as Otus semitorques.

기업정보화 실태 및 e-비즈니스 확산전략에 관한 연구 -강원.춘천권역을 중심으로- (A Study on the Informatization of the Enterprises and Enlarge Strategies of E-business -Focused on GangWon-Do, Chunchon Area-)

  • 엄광열;김치호
    • 통상정보연구
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    • 제5권1호
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    • pp.3-20
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    • 2003
  • IT evolution and the e-business has emerged as a new economic activity and beyond the time and space limitations. But the enterprises located in GangWon-Do area have been too inactive in their willingness and readiness to adopt e-business models and processes owing to the lack of the directions of e-business, the insufficient network infrastructures and capitals, etc. In this circumstance, as part of this research, this papers have conducted a survey on the e-business and information conditions and status among the enterprises located in GangWon-Do Chuncheon area. In conclusions, this study on the informatization of the enterprises and e-business enlarge strategies for building competition of local enterprises located in GangWon-Do Chuncheon area.

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The Necessity and Future Challenges of Science, Technology, Society and Humanities Fusion Research in Korea

  • Song, Wichin
    • STI Policy Review
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    • 제1권4호
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    • pp.29-39
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    • 2010
  • Science, technology, society and humanities (STSH) fusion research is aimed at creating new research areas and methods that can resolve complicated issues in society that cannot be solved by a single academic discipline. This study identifies initiatives that can promote STSH fusion research in Korea. We review the definition and characteristics of STSH fusion research to analyze the necessity of STSH fusion research with a focus on the structural changes in the S&T environment. The emergence and diffusion of generic technologies, transition to post catch-up innovation mode, and the evolution of policy to the third generation innovation policy are identified as notable changes. This paper briefly reviews the status of fusion research underway and presents initiatives to promote STSH fusion research.

Functional annotation of de novo variants from healthy individuals

  • Lee, Jean;Hong, Sung Eun
    • Genomics & Informatics
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    • 제17권4호
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    • pp.46.1-46.7
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    • 2019
  • The implications of germline de novo variants (DNVs) in diseases are well documented. Despite extensive research, inconsistencies between studies remain a challenge, and the distribution and genetic characteristics of DNVs need to be precisely evaluated. To address this issue at the whole-genome scale, a large number of DNVs identified from the whole-genome sequencing of 1,902 healthy trios (i.e., parents and progeny) from the Simons Foundation for Autism Research Initiative study and 20 healthy Korean trios were analyzed. These apparently nonpathogenic DNVs were enriched in functional elements of the genome but relatively depleted in regions of common copy number variants, implying their potential function as triggers of evolution even in healthy groups. No strong mutational hotspots were identified. The pathogenicity of the DNVs was not strongly elevated, reflecting the health status of the cohort. The mutational signatures were consistent with previous studies. This study will serve as a reference for future DNV studies.

ABSOLUTE PARAMETERS AND MASS-RADIUS-LUMINOSITY RELATIONS FOR THE SUB-TYPES OF W UMα BINARIES

  • AWADALLA N. S.;HANNA M. A.
    • 천문학회지
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    • 제38권2호
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    • pp.43-57
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    • 2005
  • The authors have assembled a sample of 80 W UMa binary systems (42 W-subtype and 38 A-subtype) whose light curves have all been solved by means of the recent W-D code and combined with up-to-date radial velocity solutions. The absolute parameters (masses, radii and luminosities) have been derived (without any constraint on the physical parameters). The main results of this paper are: (1) the mass-luminosity relations for both W&A-subtypes. as well as for all W UMa contact binaries have been shown, (2) the mass-radius relations have been found for both subtypes, (3) some remarks on the evolution status have been presented.