• Nuclear Engineering and Technology
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• v.44 no.5
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• pp.471-482
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• 2012

To assess the risk of nuclear power plant operation and to determine the risk impact of digital systems, there is a need to quantitatively assess the reliability of the digital systems in a justifiable manner. The Probabilistic Risk Analysis (PRA) is a tool which can reveal shortcomings of the NPP design in general and PRA analysts have not had sufficient guiding principles in modelling particular digital components malfunctions. Currently digital I&C systems are mostly analyzed simply and conventionally in PRA, based on failure mode and effects analysis and fault tree modelling. More dynamic approaches are still in the trial stage and can be difficult to apply in full scale PRA-models. As basic events CPU failures, application software failures and common cause failures (CCF) between identical components are modelled.The primary goal is to model dependencies. However, it is not clear which failure modes or system parts CCF:s should be postulated for. A clear distinction can be made between the treatment of protection and control systems. There is a general consensus that protection systems shall be included in PRA, while control systems can be treated in a limited manner. OECD/NEA CSNI Working Group on Risk Assessment (WGRisk) has set up a task group, called DIGREL, to develop taxonomy of failure modes of digital components for the purposes of PRA. The taxonomy is aimed to be the basis of future modelling and quantification efforts. It will also help to define a structure for data collection and to review PRA studies.

• Animal cells and systems
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• v.10 no.3
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• pp.121-123
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• 2006

In this study we reinvestigated the taxonomy of the collared many-toothed snake (Korean name: Bibaribem) of Jeju Island, Korea. The Bibari-bem is a colubrid indigenous to Jeju Island and was first assigned to S. collaris Gray. However, the geographic distribution of S. collaris is not continuous with the Korean peninsula, making it doubtful that Bibari-bem should be assigned to it. Some herpetologists have suggested that Bibari-bem may instead belong to the closely related S. chinensis G?nther. To resolve this conflict, we compared the diagnostic characteristics of S. collaris and S. chinensis as described in the literature with the characteristics of individuals collected on Jeju Island. We collected six individuals with one preocular, two postocular, two anterior temporal, and no lower ocular scales. Five individuals had nine (3-3-3 form) supralabials, among which fourth to sixth are touching the orbit and the ninth is the largest. One individual had eight (2-3-3 form) supralabials, third to fifth touching the orbit, with the eighth being the largest. These data suggest that Bibari-bem is not S. collaris, but S. chinensis.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.183-189
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• 2014

The genus Echinochloa (L.) P. Beauv. comprised of approximately 30-40 species in the tropical and warm temperate regions of the world, including numerous interspecific and intraspecific types which make the genus difficult to identify. As an attempt to identify the species within the genus easier, the taxonomy of the genus Echinochloa, Poaceae in Korea was reviewed on the basis of sequencing data derived from nuclear ribosomal DNA internal transcribed spacer (ITS) and external transcribe spacer and chloroplast DNA trnL intron, trnL-F intergenic spacer and matK regions using a total of 46 accessions representing all the species in Korea. The results of maximum parsimony found separate lineage comprised of E. colona and E. frumentaceae which are not Korean species, but no resolution within Korean Echinochloa species, supporting the suggestion of Yamaguchi group that E. crus-galli, E. oryzoides, and E. esculenta should be considered to belong to the same species. However, the relationship between these three species and the other species, i.e. E. oryzicola should be better understood with more detail studies.

• ALGAE
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• v.28 no.4
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• pp.307-330
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• 2013

The genus Cryptomonas is easily recognized by having two flagella, green brownish color, and a swaying behavior. They have relatively simple morphology, and limited diagnostic characters, which present a major difficulty in differentiating between species of the genus. To understand species delineation and phylogenetic relationships among Cryptomonas species, the nuclear-encoded internal transcribed spacer 2 (ITS2), partial large subunit (LSU) and small subunit ribosomal DNA (rDNA), and chloroplast-encoded psbA and LSU rDNA sequences were determined and used for phylogenetic analyses, using Bayesian and maximum likelihood methods. In addition, nuclear-encoded ITS2 sequences were predicted to secondary structures, and were used to determine nine species and four unidentified species from 47 strains. Sequences of helix I, II, and IIIb in ITS2 secondary structure were very useful for the identification of Cryptomonas species. However, the helix IV was the most variable region across species in alignment. The phylogenetic tree showed that fourteen species were monophyletic. However, some strains of C. obovata had chloroplasts with pyrenoid while others were without pyrenoid, which used as a key character in few species. Therefore, classification systems depending solely on morphological characters are inadequate, and require the use of molecular data.

• Korean journal of applied entomology
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• v.60 no.3
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• pp.331-334
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• 2021

A cosmopterigid species, Alloclita mongolica Sinev is reported for the first time from Korea. This is the first record of the genus Alloclita Staudinger for the Korean fauna and the southernmost records of A. mongolica. The collecting data of the species in Korea suggest a habitat association of A. mongolica with coastal sand-dunes. The features of external appearance and male genitalia are described and illustrated for this rare species.

• Animal Systematics, Evolution and Diversity
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• v.26 no.1
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• pp.29-33
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• 2010

The genus Caconemobius comprises marine apterous crickets. In recent years, two species have been confirmed in Korea: Caconemobius sazanami (Furukawa, 1970) and Caconemobius takarai ($\hat{O}$shiro, 1990). A key to species, descriptions, distribution data, photographs, and figures are presented to compare the two crickets.

• Animal Systematics, Evolution and Diversity
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• v.28 no.4
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• pp.297-303
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• 2012

New Korean lumbricids are described: Eisenia gaga Blakemore sp. nov. from remote Gageodo Island and E. sindo Blakemore, sp. nov. from an island at Incheon. Both are comparable to Eisenia koreana (Zicsi, 1972) from near Pyongyang, North Korea. A remarkable yet previously unrecognized similarity to American earthworm Eisenoides carolinensis (Michaelsen, 1910) is discussed, but synonymy is rejected on tenuous morphological grounds (form of nephridial vesicle bladders) with taxonomy supported by objective molecular data (mtDNA cytochrome c oxidase subunit 1 barcodes).

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.15-18
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• 2005

In Korea, researches on distance education had started in early 1980th, and began in earnest from mid 1990th. In this study, we classified academic journals which were searched by the key word of 'Distance Education" from the Database of the Library of Congress. We proposed arithmetic statistical data and implication.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04a
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• pp.691-693
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• 2001

DASE(Digital TV Application Software Environment)는 데이터 방송을 위한 국제 표준으로 MPEG-2 TS(Moving Picture Experts Group-2 Transport Stream) 형식의 데이터를 처리한다. 소스코드 대신 입력 데이터 명세 정보만을 공개하는 특성상 DASE 시스템의 오류를 테스트하기 위해서는 테스트 데이터에 오류를 삽입하는 방법이 적합하고 이를 위해 MPEG-2 표준을 위한 오류 항목을 개발이 요구된다. 본 논문에서는 관계형 데이터 베이스를 위한 데이터 분류인 Kim’s et al 분류를 근거로 하여 MPEG-2 표준을 위한 오류 항목을 개발하였다. 이는 DASE 시스템의 오류 삽입 테스트 기법에 유용하게 사용될 수 있을 것이다.

• The Korean Journal of Mycology
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• v.50 no.2
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• pp.115-123
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• 2022

Two new records of Scleroderma species from South Korea are described here. Comprehensive taxonomic studies of Scleroderma specimens were conducted at the Korea National Arboretum. Based on morphological and molecular data (fungal barcode sequences), two new records (S. laeve and S. nastii) were confirmed. Herein, morphological descriptions, including Scanning Electron Microscope (SEM) images of basidiospore ornamentation, and a taxonomic key of Korean Scleroderma species are provided.