• Title/Summary/Keyword: Collection Study

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Effects of Spray Surfactant and Particle Charge on Respirable Coal Dust Capture

  • Tessum, Mei W.;Raynor, Peter C.
    • Safety and Health at Work
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    • v.8 no.3
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    • pp.296-305
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    • 2017
  • Background: Surfactant-containing water sprays are commonly used in coal mines to collect dust. This study investigates the dust collection performance of different surfactant types for a range of coal dust particle sizes and charges. Methods: Bituminous coal dust aerosol was generated in a wind tunnel. The charge of the aerosol was either left unaltered, charge-neutralized with a neutralizer, or positively- or negatively-charged using a diffusion charger after the particles were neutralized. An anionic, cationic, or nonionic surfactant spray or a plain water spray was used to remove the particles from the air flow. Some particles were captured while passing through spray section, whereas remaining particles were charge-separated using an electrostatic classifier. Particle size and concentration of the charge-separated particles were measured using an aerodynamic particle sizer. Measurements were made with the spray on and off to calculate overall collection efficiencies (integrated across all charge levels) and efficiencies of particles with specific charge levels. Results: The diameter of the tested coal dust aerosol was $0.89{\mu}m{\pm}1.45$ [geometric $mean{\pm}geometric$ standard deviations (SD)]. Respirable particle mass was collected with $75.5{\pm}5.9%$ ($mean{\pm}SD$) efficiency overall. Collection efficiency was correlated with particle size. Surfactant type significantly impacted collection efficiency: charged particle collection by nonionic surfactant sprays was greater than or equal to collection by other sprays, especially for weakly-charged aerosols. Particle charge strength was significantly correlated with collection efficiency. Conclusion: Surfactant type affects charged particle spray collection efficiency. Nonionic surfactant sprays performed well in coal dust capture in many of the tested conditions.

An Analysis of Korean University Library Holdings of Western Language Books Using a Union Catalog Database (종합목록DB를 이용한 국내 대학도서관 서양서 소장 실태 분석)

  • Lee, Ji-Won;Lee, Jae Yun
    • Journal of the Korean Society for information Management
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    • v.35 no.1
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    • pp.205-229
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    • 2018
  • This study analyzed Korean university libraries' holdings of Western language books published in 2003 and 2013 using the KERIS union catalog with a view to investigating the changes in collection development of Western language books in the libraries. To do that, new collection indexes - holding h-index, CUI (Collection Uniqueness Index), and CCHR (Common Collection Holding Ratio) - were suggested, and they were used with basic indexes such as the number of titles, the number of books, and the number of books per title. The analysis reveals that compared to those published in 2003, the number of titles was decreased by 16.1% with those published in 2013, and the number of books dropped more sharply, by 42.2%. Also, in 2013, CCHR was decreased while CUI was increased. In terms of subject, among DDC main classes, 0XX (Generalities) showed the greatest decrease rate in both the number of titles and books because of the radical reduction of computer-related books. In terms of each library's holdings, the number of Western language books held by top libraries has been increased with those published in 2013.

A Survey and Analysis of Current Collection Management State in School Libraries (학교도서관의 장서관리 현황조사 및 분석)

  • Kim, Sung-Jun;Lee, Byeong-Ki
    • Journal of Korean Library and Information Science Society
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    • v.48 no.1
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    • pp.21-42
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    • 2017
  • This study reports the result of the survey on collection management from 154 school libraries in Korea. The questionnaire is consisted of three section: state of collection, state of book use, and collection management system. Results reveal that (1) elementary schools and middle schools have many books for each student compared to the KLA's School Library Standards; (2) the component ratio of literature books is the biggest in school library collections; (3) the ratio of library book use is overwhelmingly higher in elementary schools than middle schools and high schools; (4) 64.6 percent of library books in the sample are never used during 2013-2015; (5) 74 percent of libraries have its own collection management document; (6) Almost all schools compose its own committee for library management, the committee plays an important roles in the communication among school members, collection development and promotion.

Kitsch Features Expressed in Contemporary Men's Collection (현대 남성복 컬렉션에 나타난 키치(Kitsch) 특성)

  • Yoo, Hyunseo;Yoon, Jung-A;Lee, Younhee
    • Journal of the Korea Fashion and Costume Design Association
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    • v.17 no.2
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    • pp.11-25
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    • 2015
  • This study analyzed features in contemporary men's collection to provide data for characteristics of kitsch in men's collection. The research method was to see background of the concept of kitsch through the domestic and international publications, the Internet, paper. Five designers' collections that have characteristics of kitsch were selected. The range of collection is from the 2000 S/S to 2011 F/W in Men's collection. The results are as follows: kitsch characteristics could be classified by amusements, inappropriateness, satire. First, exaggerative amusements in men's collection appeared exaggerated form, large size, which is ridiculous at the same time. Infantile amusements represents the image of a pure concentric matching accessories such as toys to the children express. sensual amusements reveals the sexual instincts and desires and people can feel satisfaction through sensual amusements. Second, inappropriateness is characteristic of kitsch to escape from normal life. Clothing does not fit the body and destroyed the design or design of this feature appears. It looks clumsy and strange. Inappropriateness characteristic in men's collection can be divided into inadequate performance and sexual inappropriateness. Third, satire can be divided into resistant satire, imitative satire, and popular satire. Resistance satire with anti-social tendencies through their clothing is achieved by expressing their needs. It was affected by sub-culture like Hippie or Punk. Imitative satire is to imitate other culture, customs and race. It is to resolve complaints through the consumption of things in disparities of wealth and materialism in the society. Popular satire is to express emotions that are free using materials that can recycling like can, bottle or paper.

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Study on the Performance Improvement of Active RFID System (능동형 RFID 시스템의 성능 향상을 위한 연구)

  • Kim, Ji-Tae;Kim, Jin-Sung;Lee, Kang-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.5
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    • pp.871-885
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    • 2015
  • The improved DFSA for 2.4GHz multi-tags active RFID is suggested in 2 different ways: 1) simplified tag collection and Ack procedure using query command and 2) modified Schoute's method to control the number of slots in the frame. To evaluate the performance of the improved system we develop the simulation model. Varying the number of tags in the system we track the performance measures such as throughput, recognition time for multi-tags and tag recognition rate during a given time. The suggested method shows the best performance over all measures. Simplification of collection and Ack commands using query commands contributes to reducing tag recognition time. And the modified Schoute's method which controls the frame size using $k_1$ and $k_2$ contributes to throughput improvement and reduces target cognition time by reducing the number of collection rounds.

Functions and Characteristics of Public Library Theme Collection: Focusing on the User-centered Classification Perspective (공공도서관 테마 컬렉션의 기능과 특성 - 이용자 중심 분류의 관점에서 -)

  • Baek, Ji-Won
    • Journal of the Korean Society for Library and Information Science
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    • v.52 no.4
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    • pp.51-69
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    • 2018
  • The purpose of this study is to analyze the potential use of the theme collection as a new classification method that reflects the interest of users in terms of classification and categorization. For this purpose, the background of the theme collection was identified based on the discussion of the library resource organization and the introduction of the curation service of bookstore. In addition, based on case analysis, which is building the theme collection, concrete concepts and characteristics of theme collection are derived. Based on the above discussion, the classification and categorization characteristics of public library themes collections were analyzed, and the characteristics and functions as a classification were compared with other categories relatively. Finally, the utility and applicability of the theme collection is presented and it is based on the discussions about the user-centered classification system design of the library in the future.

Re-identification of Colletotrichum gloeosporioides Species Complex Isolates in Korea and Their Host Plants

  • Le Dinh Thao;Hyorim Choi;Yunhee, Choi;Anbazhagan Mageswari;Daseul Lee;Dong-Hyun Kim;Hyeon-Dong Shin;Hyowon Choi;Ho-Jong Ju;Seung-Beom Hong
    • The Plant Pathology Journal
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    • v.40 no.1
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    • pp.16-29
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    • 2024
  • The Colletotrichum gloeosporioides species complex includes many phytopathogenic species, causing anthracnose disease on a wide range of host plants and appearing to be globally distributed. Seventy-one Colletotrichum isolates in the complex from different plants and geographic regions in Korea were preserved in the Korean Agricultural Culture Collection (KACC). Most of them had been identified based on hosts and morphological features, this could lead to inaccurate species names. Therefore, the KACC isolates were re-identified using DNA sequence analyses of six loci, comprising internal transcribed spacer, gapdh, chs-1, his3, act, and tub2 in this study. Based on the combined phylogenetic analysis, KACC strains were assigned to 12 known species and three new species candidates. The detected species are C. siamense (n = 20), C. fructicola (n = 19), C. gloeosporioides (n = 9), C. aenigma (n = 5), C. camelliae (n = 3), C. temperatum (n = 3), C. musae (n = 2), C. theobromicola (n = 2), C. viniferum (n = 2), C. alatae (n = 1), C. jiangxiense (n = 1), and C. yulongense (n = 1). Of these, C. jiangxiense, C. temperatum, C. theobromicola and C. yulongense are unrecorded species in Korea. Host plant comparisons showed that 27 fungus-host associations are newly reported in the country. However, plant-fungus interactions need to be investigated by pathogenicity tests.

Re-identification of Korean Isolates in the Colletotrichum dematium, C. magnum, C. orchidearum, and C. orbiculare Species Complexes

  • Le Dinh Thao;Hyorim Choi;Donghun Kang;Anbazhagan Mageswari;Daseul Lee;Dong-Hyun Kim;In-Young Choi;Hyeon-Dong Shin;Seung-Beom Hong
    • The Plant Pathology Journal
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    • v.40 no.5
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    • pp.425-437
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    • 2024
  • A large number of species in the genus Colletotrichum have been reported as causal agents of anthracnose on crops and wild plants in Korea. Many Colletotrichum isolates from the country preserved in the Korean Agricultural Culture Collection (KACC) were previously identified based on host plants and morphological characteristics, and it may lead to species misidentification. Thus, accurate fungal species identification using multilocus sequence analyses is essential for understanding disease epidemiology and disease management strategies. In this study, combined DNA sequence analyses of internal transcribed spacer, gapdh, chs-1, his3, act, tub2, and gs were applied to re-identify 27 Colletotrichum isolates in KACC. The phylogenetic analyses showed that the isolates resulted in 11 known species, they belong to the C. dematium species complex (C. hemerocallidis, C. jinshuiense, and C. spinaciae), the C. magnum complex (C. kaifengense and C. cf. ovatense), the C. orchidearum complex (C. cattleyicola, C. plurivorum, C. reniforme, and C. sojae) and the C. orbiculare complex (C. malvarum and C. orbiculare). Of them, C. cattleyicola, C. hemerocallidis, C. kaifengense, and C. reniforme were unrecorded species in Korea. In the view of host-fungus combinations, 10 combinations are newly reported in the world and 12 are new reports in Korea, although their pathogenicity on the host was not confirmed.

Studies on Reproductive Capacity of Korean Native Bulls I. Effects of Age, Season and Collection Frequency on Semen Volume, Sperm Concentration, Total Sperm and Sperm Motility in Bulls (한우 종모우의 번식능력에 관한 연구 1. 종모우의 연령, 계절 및 채취빈도가 정액량, 정자농도, 총정자수 및 정자활력에 미치는 영향)

  • 김선환;김기구;유규종;고석권;김경주;김충기;김창근;정영채
    • Korean Journal of Animal Reproduction
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    • v.5 no.2
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    • pp.35-42
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    • 1981
  • A total 2,488 ejaculates during 4 years from 80 Korean native bulls over the age from 3 to 12 years of bull herds of Artificial Breeding Center, National Livestock Federatives Cooperation were collected and analyzed to study the effects of collection year, age of bulls, month of years, collection interval and ejaculation frequency per day on semen volume, sperm concentration, total sperm per ejaculate and sperm motility. 1. Semen volume, sperm concentration, total sperm per ejaculate and sperm motility index for the all ejaculates using least squares procedure averaged 5.73ml, 9.133${\times}$108/ml, 52.527${\times}$108 and 62.81, respectively. 2. Semen volume varied significantly with collection year, collection interval and ejaculation frequency per day(P<0.01), but effects of age of bulls and month of years on semen volume were not significant. Eight to 15 days collection interval showed the highest volume, and 1st ejaculate contained 5.6% more volume than 2nd ejaculate. 3. There were significant differences among collection years, months of years and ejeculation frequencies per day except collection intervals in sperm concentration per ml(P<0.05, P<0.01). Six to 8-year-old bulls was the highest concentration. Higher sperm concentration per ml was in April to July and lower month was October and December. Sperm concentration in 2nd ejaculate was higher than in 1st ejaculate. 4. Total sperm per ejaculate affected by all environmental factors studied(P<0.05, P<0.01). Age of bulls, collection interval and ejaculation frequency per day showed the highest total sperm was 6 to 8-year-old bulls, 8 to 15 days interval and 1st ejaculate, respectively. Higher total sperm per ejaculate was in April to July and lower total sperm was in September to December. 5. In sperm motility, there were significant differences among collection years, ages of bulls and collection intervals except months of years and ejaculation frequencies (P<0.01). Higher sperm motility was in 6 to 12-year-old bulls and in 5 to 7 days collection interval.

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Approaches to Studying Low Birth Rate in Korea: A Critical Review (우리나라 저출산 관련 연구 동향 분석)

  • Na, Yu-Mi;Kim, Mi-Kyung
    • Korean Journal of Human Ecology
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    • v.19 no.5
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    • pp.817-833
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    • 2010
  • This study was dedicated to searching better course of low birth rate study in Korea by carefully analyzing past and present low birth rate researches. For this 179 studies(101 master thesis and 78 journal articles) from 1991 to 2009 were analyzed. Next, using SPSS Win 12.0, the research type, topic, participants, data collection and method of data analysis were compared to the studies' years of publication. The most frequently applied research approach, topic, sampling method, data collection procedure and data analysis method in the research was found to be a literature study, solution and prevention of low birth rate related policy, literature study, literacy analysis. In conclusion, low birth rate studies should become more diversified in terms of types of the research, data collection method, and data analysis. Additionally, research topics should become more realistic and specified. Moreover, research results should be verified before they are applied to the policy.