• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.7
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• pp.636-644
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• 2007

36,000lbs porcelain insulators of D-1995, D-1997 and D-2002 investigated mechanical and electrical qualities, where is process of using in the Korea 154 kV transmission lines. It analyzes the cause of the elapse of a year aging of the transmission insulators. Weibull distribution function, product quality and uniform quality, etc. investigated for prediction to extant life of insulator. It calculate change as statistical elapse of a year through product qualities of used insulator and new insulator, uniform equality and uniformity of insulator. In case of D-1995 year used insulator, it decided to badness decline index k by 0.0237, badness quality index by 1.0 and 3.0. Result of extant confidence life Ym was calculated that remain each 4 yens and 0.7 yens that uniformity index is considered. Extant life of D-1997 and D-2002 insulators Predicted by about 40 years.

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.131.1-131
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• 2003

No Abstract, See Full Text

• Animal cells and systems
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• v.11 no.2
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• pp.147-153
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• 2007

DNA extracted from ancient bones of Cervidae animals was examined to identify the species and to determine the phylogenetic relationships to those from extant cervids. Abundant ancient bones were excavated from Kumsung archaeological site in Jeju Island, Korea, and were identified as Cervidae animals based on morphological features of their antlers and lower mandibles. Their mitochondrial DNA (mtDNA) control region (CR) was partially sequenced and subsequently compared with those previously reported in database. The results confirmed that the ancient sequences are lineage of Cervidae. On the phylogenetic trees constructed using the sequence diversity of the CR sequences of family Cervidae, the ancient DNA sequences were found on distinct clusters. The ancient sequences were located in the subfamily Capreolinae cluster, and six ancient sequences were closely related to those of extant Korean roe deer in Jeju Island and Korean Peninsula. Consequently, the results of this study suggest that the roe deer inhabited Jeju Island in ancient times. However, there is no evidence for the existence of subfamily Cervinae, including Sika deer, while it has been described in several historical records. The results suggest that this finding could contribute to understanding of the origin and phylogenetic relationships of extant and ancient roe deer on Jeju Island.

• Journal of Species Research
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• v.8 no.1
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• pp.1-96
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• 2019

The suborder Symphyta comprises more than 8,000 described species worldwide, of which about 4,400 extant species are recorded from the Eastern Palaearctic. Symphyta can be easily distinguished from the suborder Apocrita by the abdomen, which is broadly joined to the thorax. The larvae of most species feed on herbaceous to woody. A list of the 418 described species of Symphyta in Korea is presented. The list is in taxonomic sequence by superfamily, family, subfamily and genus and includes 116 genera in 22 subfamilies, 12 families, and seven superfamilies. We provide the page reference of the original description of every species and genus listed, Korean name, host records, and all Korean records. The list also provides the distribution of all the species by country.

• Molecules and Cells
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• v.20 no.3
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• pp.325-330
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• 2005

Ancient cattle bones were excavated from archaeological sites in Jeju, Korea. We used molecular genetic techniques to identify the species and establish its relationship to extant cattle breeds. Ancient DNA was extracted from four sources: a humerus (Gonae site, A.D. 700-800), two fragments of radius, and a tooth (Kwakji site, A.D. 0-900). The mitochondrial DNA (mtDNA) D-loop regions were cloned, sequenced, and compared with previously reported sequences of various cattle breeds (9 Asian, 8 European, and 3 African). The results revealed that these bones were of the breed, Bos taurus, and a phylogenetic tree indicated that the four cattle bones formed a monophyletic group with Jeju native black cattle. However, the patterns of sequence variation and reports from archaeological sites suggest that a few wild cattle, with a different maternal lineage, may have existed on Jeju Island. Our results will contribute to further studies of the origin of Jeju native cattle and the possible existence of local wild cattle.

• Journal of Species Research
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• v.8 no.4
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• pp.389-394
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• 2019

Foraminifera are protists that inhabit diverse marine environments and show high abundance and diversity. However, previous studies on foraminifera in Korea mostly focused on geological and paleoecological fields and were conducted in a limited area. Therefore, there is a high possibility for discovering new and unrecorded species. Here we describe three newly recorded foraminiferal species from the southwestern part of Jeju Island during a survey on the meiofaunal community, which belongs to three different genera (Ammobaculites, Cylindroclavulina, Saracenaria), three families (Lituolidae, Vaginulinidae, Valvulinidae), and three orders (Lituolida, Textulariida, Vaginulinida): Ammobaculites formosensis Nakamura, 1937, Cylindroclavulina bradyi (Cushman, 1911), and Saracenaria hannoverana (Franke, 1936). These species have been reported from Chinese region in the East China Sea, however this is the first report from Korean waters. Particularly, Cylindroclavulina bradyi is the first report of the genus Cylindroclavulina in Korean waters. The present study supports the diversity of foraminiferal species in Korea, and the necessity of further surveys in Korean waters.

• Journal of Species Research
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• v.10 no.3
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• pp.255-261
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• 2021

Sclerochilus Sars, 1866 is the most diverse genus of the family Bythocytheridae, one of the longest surviving groups of extant ostracods, and the oldest representative of the superfamily Cytheroidea. It has a worldwide distribution at various marine depths, and it includes three subgenera: Fascichilus Schornikov, 1981; Praesclerochilus Schornikov, 1981; and Sclerochilus Sars, 1866. We describe Sclerochilus(Praesclerochilus) jejuensis sp. nov. from Jeju Island, South Korea, raising the number of known Praesclerochilus species to 13. Although most species belonging to this subgenus have very similar carapace shape, the new species differs morphologically from its most similar congeners, S. (P.) mukaishimensis Okubo, 1977; S. (P.) pruniformis Schornikov, 1981; and S. (P.) ochotensis Schornikov, 1981, by the large ventral process on the hemipenis. So far, 29 Sclerochilus species have been reported from South Korea, only one of which was named, but for which no descriptive information was provided. Therefore, this is the first taxonomic report of a Sclerochilus species from South Korea.

• Journal of Biosystems Engineering
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• v.42 no.3
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• pp.199-216
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• 2017

Purpose: This study reviewed the major nondestructive measurement techniques used to assess internal properties of agricultural materials that significantly influence the quality, safety, and value of the products in markets. Methods: Imaging technologies are powerful nondestructive analytical tools that possess specific advantages in revealing the internal properties of products. Results: This review was exploring the application of various imaging techniques, specifically, hyperspectral imaging (HSI), magnetic resonance imaging (MRI), soft X-ray, X-ray computed tomography (XRI-CT), thermal imaging (TI), and ultrasound imaging (UI), to investigate the internal properties of agricultural commodities. Conclusions: The basic instruments used in these techniques are discussed in the initial part of the review. In the context of an investigation of the internal properties of agricultural products, including crops, fruits, vegetables, poultry, meat, fish, and seeds, various extant studies are examined to understand the potential of these imaging technologies. Future trends for these imaging techniques are also presented.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.1
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• pp.19-29
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• 2023

Logistics industry is being an important industry in Vietnam with the contribution from 8-10% of GDP recently. This industry employs about 15 millions people. Increasing the employees' job satisfaction is become one of the most concerns of managers in logistics companies to strengthen the employee engagement and improve their business performance. The aim of this study is to investigate how employees' perceptions of job satisfaction are influenced by factors such as job stress, leadership capability, work-life balance, and demographics. 426 workers in the logistics sector in Vietnam were surveyed online. The acquired data was analyzed using a structural equation model. In total 16 hypotheses were established, 13 of which were deemed to be significant. The results demonstrate how the literature-informed second-order constructs can potentially explain the overall job stress, leadership capability, and work-life balance of employees in the Vietnamese logistics industry. These variables account for 54.8% of job satisfaction. This study makes a theoretical contribution to the extant literature by showing how researching second-order constructs can improve the theory's capacity to predict employees' job satisfaction. The paper concludes with a set of recommendations for the management of logistics firms in Vietnam.

• Journal of Korean Library and Information Science Society
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• v.49 no.4
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• pp.405-427
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• 2018

This study examined system, form and contents of including its publication in depth through the analysis on the publication of those days, present condition of extant edition, system and publication, illustrator etc., targeting series which was published in the liberation period. As for series which was published by Eulyoo Publishing and Joseon Children Culture Association(Ahyeop) for building children's life liberation and children culture, 5 books still remain now. For the extinct edition, this study confirmed publication history of books based on the advertisement carried on the newspaper which was published of the time. As a result of analyzing extant edition, this study found that the book was composed equally as a system of cover, beginning, body and the end, and the body was characterized by the composition of 3-cut comic and story as a form of storybook. The size of the book is A5 book size with 32 pages of quantity and was published as a semi-hardcover bound book. As for illustrators, Kim brothers (Yong-hwan, Eui-hwan) who played an active part in the field of art of the time participated.