• Title/Summary/Keyword: systematic study

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A Systematic Literature Review of Shift Workers' Sleep in Korea (국내 교대근무자의 수면연구에 관한 체계적 문헌고찰)

  • Lee, Yeon Hwa;Yang, Young Ran
    • Korean Journal of Occupational Health Nursing
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    • v.31 no.3
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    • pp.125-136
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    • 2022
  • Purpose: The aim of this systematic literature review was to synthesize and investigate the effects of shift workers' sleep in Korea. Methods: A search was conducted through three electronic databases using keywords such as "shift work" or "rotation work" and "sleep", with sleep as the independent variable, and 17 papers were reviewed. Results: The design of those 17 studies was analyzed in a cross-sectional analysis. The most commonly measured characteristic was quality of sleep, whereas the others were sleep disturbance, sleep efficiency, and sleepiness. The study outcome variables were job-related factors, mental health, wellness, stress, fatigue, and metabolic syndrome. Conclusion: The results inform sleep and health-promoting behaviors and improvement in shift workers' working condition.

A study on (n, α) reaction cross sections using a new empirical systematic

  • Sema Kucuksucu;Mustafa Yigit
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.4026-4031
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    • 2023
  • In this article, we report a new empirical formula for quick calculation of cross sections of (n, α) reactions with 14-15 MeV neutrons. Cross sections are analysed in terms of the compound nucleus model. A systematic trend for 14-15 MeV neutrons is found in the variation of (n, α) reaction cross sections with the parameters (N - Z + 1), (En + Q)0.5 and N/Z. The empirical relation between the cross sections and these parameters has been obtained, which give fairly good fits with the experimental data. We have also investigated the odd-even effects on (n, α) cross sections considering binding energy systematic of the shell model. The present formula is very useful in predicting of the (n, α) cross sections, where the measurements are not available as well as in testing new experimental data.

A Study on the Volumetric Error Equation of Coordinate Measuring Machines and their Application (3차원 좌표측정기(CMM)의 오차방정식 유도에 관한 연구)

  • 이응석
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.6
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    • pp.1545-1553
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    • 1995
  • For general geometry of Coordinate Measuring Machine (CMM), volumetric error equation including 21 systematic error components was showed using vector expression. Different types of CMM listed on an international standard (BS 6808) were classified according to their geometry, and the general volumetric error equation was used for the CMMs. Application of volumetric error equation was also introduced, such as position error compensation, error equation of CNC-machine and parametric error analysis, etc.

A Study on the Education of Creative Engineering Design Methodology (창의적 공학설계방법론 교육에 관한 연구)

  • Lee, Kun-Sang;Kim, Kang
    • Journal of Engineering Education Research
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    • v.15 no.4
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    • pp.94-100
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    • 2012
  • The needs for enhancing creativity in engineering design education continue to increase. Recent studies about a learning environment and learning support tools provide some new possibilities. The education of creative thinking however must begin from the change of attitude of students to creativity. The experimental results and some lessons for modification of systematic engineering design methodology to creative were reported from the course 'engineering design'.

Systematic Study on the Ophiuroidea from Cheju Island , Korea (제주도산 사미류의 분류학적 연구)

  • Rho, Boon-Jo;Shin, Sook
    • Animal Systematics, Evolution and Diversity
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    • v.3 no.2
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    • pp.208-224
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    • 1987
  • 제주도산 사미류의 분류학적 연구를 하기 위하여 1965년 7월부터 1987년 7월까지 제주도의 6개 지역(제주도, 비양도, 서귀포, 신천, 역산포, 우도)에서 채집하여 보관중이던 표본을 동정·분류하였다. 그 결과 2 복 9과 19종의 사미류가 제두도에 분포하고 있는 것으로 밝혀졌고, 이들중 Gorgonocephalus dolichodactylus Dderlein , 1911, Astrocladus ludwigi9Dderlein, 1896) , Astroboa arctos Matsumoto, 1915 al camphipholis pugetana Lyman , 1861 4 종은 한국미기록종이다.

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A Systematic Study on the Marine Sponges from the South Sea and the Yellow Sea of Korea (한국 남해 및 서해 연안 해산 해면류의 계통분류학적 연구)

  • 심정자
    • Animal Systematics, Evolution and Diversity
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    • v.1 no.1_2
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    • pp.21-30
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    • 1985
  • 본인은 1984년 6월부터1985년 5월까지 서해연안(작약도, 대천, 안면도, 안흥)과 남해연안의 삼천포를 중심으로 한 부근섬(신수도, 늑도, 비진도, 충무) 및 거제도, 제주도 등지에서 채집된 재료 90여점과 그간 미해결로 보류되어있던 기존 표본들을 동정분류한 결과 26 종의 기록종과 3 종의 한국 미기록종(Spongia officienalis , S. zimmocca, Tedania Tublifera)이 밝혀졌다. 기록종 가운데 Esperiopsis uncigera 와 Hymeniacidon sinapium은 재검토되었다.

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A Systematic Study on Maintenance of R/C Structures (콘크리트 구조물의 유지관리에 관한 체계적 연구)

  • 심종성;문일환
    • Proceedings of the Korea Concrete Institute Conference
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    • 1989.10a
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    • pp.39-42
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    • 1989
  • This paper suggests a systematic procedure for maintenance of reinforced concrete (R/C) structures. In this paper the deteriorations of R/C structures are classified by eleven causes and diagonistic techniques are devided into six major steps. The suggested diagonisis steps are summarized in the flow chart and it would be helpful to develop the expert system for maintenance of R/C structures.

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Development and Testing of a New Area Search Model with Partially Overlapping Target and Searcher Patrol Area

  • Kim, Gi-Young;Eagle, James N.;Kang, Sung-Jin
    • Journal of the military operations research society of Korea
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    • v.35 no.1
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    • pp.21-32
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    • 2009
  • In this study, the author uses a MATLAB simulation to develop and test a generalization of the traditional Random Search model which allows both the searcher and target to move and to be in different, but overlapping, areas. Also the best evasion speed for a randomly moving target against a Systematic Search is studied.

A Study on Classification of Koran Traditional Patterns Based on Their Types (한국전통문양의 유형에 따른 분류에 관한 연구)

  • 장수경
    • The Research Journal of the Costume Culture
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    • v.2 no.2
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    • pp.283-295
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    • 1994
  • A systematic classification of Korean traditional patterns has been made according to their objects and presenting methods. The classification is represented with 3 levels of categories. First, the superordinate category is composed of 7 groups of patterns, i.e. Naturals, Animals, Plants, Artifacts, Geometric, Composites, and Others. Second, the basic category is composed of motifs in each group. Third, the subordinate category is composed of 3 types, i.e. realistic, stylized, abstracted, according to the degree of simplification. As this classification is a method for organizing informations in Korean traditional patterns in a systematic way, it can offer a useful basis for computerization of the patterns.

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Systematic Study on the Marine Hyroids (Cnidaria , Hydrozoa) in Korea I (한국 해산 히드라충류 (자포동물 문, 히드라충강 )의 계통분류학적 연구 I)

  • 박정희
    • Animal Systematics, Evolution and Diversity
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    • v.6 no.1
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    • pp.71-86
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    • 1990
  • 1969년 5월부터 1989년 6월까지 한국의 본토 연안과 도서지방, 28개 지역에서 채집되어 미동정 상태로 보관되어 있는 히드라충류의 표본들 가운데 일부를 관찰한 결과 13과에 속하는 50종 및 아종이 밝혀졌다. 이중에서 5종, Turritopsis nutricula, Halecium beanii, Halecium pusillum , Sertularella gigantea and Halopteris constricta는 한국미기록종으로 판명되었다. 한국산 기지종에 대해서는 기지 채집지를 인용하였으며 , 아울러 새로운 채집지를 추가하였다.

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