• Title/Summary/Keyword: 자연과학 연구자

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Trace Metal Contents in Vegetables and Their Safety Evaluations (우리나라 채소류중 미량금속 함량 및 안전성 평가)

  • 정소영;김미혜;소유섭;원경풍;홍무기
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.1
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    • pp.32-36
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    • 2001
  • This study was conducted to estimate the contents of trace metals in vegetable which were produced in Korea. The levels of trace metals determined using a mercury analyzer, and ICP (inductively coupled plasma spectrometer) and an AAS (atomic absorption spectrophotometer) after wet digestion. The values of trace metals [minimum~maximum (mean), mg/kg] in vegetables were a follows ; Hg : 0.0001~0.019 (0.002), Pb : 0.001~0.28 (0.02), Cd : 0.001~0.078 (0.016), As : 0.001~0.06 (0.02), Cu : 0.06~24.81 (0.77), Mn : 0.17~15.12 (2.32), Zn : 0.13~28.70 (2.51). These results showed that metal contents in vegetables on domestic markets were similar to those reported in other countries. The weekly average intakes of lead, cadmium and mercury from vegetables take 2~7% of PTWI (Provisional Tolerable Weekly Intakes) that the FAO/WHO Joint Food Additive and Contaminants Committee had set to evaluate their safeties.

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Trace Metal Contents in Cereals, Pulses and Potatoes and Their Safety Evaluations (우리나라 곡류, 두류 및 서류중 중금속 함량 및 안전성 평가)

  • 김미혜;장문익;정소영;소유섭;홍무기
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.3
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    • pp.364-368
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    • 2000
  • 국내에서 생산된 곡류 9종 416건, 두류 5종 296건 및 서류 2종 156건에 대해 수은 함량은 Mercury Analyzer로, 납, 카드뮴, 비소, 구리, 망간, 아연 등은 습식분해 후 ICP로 분석하였다. 본 연구 결과, 곡류중 중금속 함량[최소~최대(평균),mg/kg]은 다음과 같았다. 수은 0.0001~0.051(0.007), 납 0.01~0.39(0.13), 카드뮴 0.001~0.098(0.023), 비소 0.01~0.38(0.09), 구리 0.06~11.85(1.73), 망간 0.91~39.15(7.47), 아연 1.35~24.15(9.32) mg/kg으로 나타났다. 또한 두류중 중금속 함량(mg/kg)은 수은 0.0002~0.031(0.005), 납 0.01~0.38(0.12), 카드뮴 0.005~0.098(0.030), 비소 0.01~0.37(0.10), 구리 0.03~6.56(2.44), 망간 0.85~22.97(8.16), 아연 2.40~40.18(11.25) mg/kg이었다 서류중 중금속 함량(mg/kg)은 수은 0.002~0.036(0.017), 비소0.01~0.20(0.08), 구리 0.02~2.91(0.84), 망간 0.26~9.48(2.54), 아연 0.35~6.11(2.23)mg/kg이었다. 본 연구에서 얻어진 분석치들은 국내외 다른 연구자들의 분석치와 비슷한 것으로 나타났으며, 이는 우리나라에서 생산된 곡류, 두류, 서류중의 중금속 함유량은 오염된 것이 아닌 자연함유량 수준인 것으로 파악되어 우리나라 사람이 이들 농산물에서 섭취하는 중금속량으로 인한 위해성은 없는 것으로 판단된다. 또한 우리나라 국민이 곡류, 두류, 서류 등을 통해 섭치하는 납, 수은, 카드뮴 등의 중금속 주간섭취량은 FAO/WHO에서 중금속 안전성 평가를 이해 정한 잠정주간섭취혀용량인 PTW1의 0.2~19%를 차지하고 있다.

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Understanding Purposes and Functions of Students' Drawing while on Geological Field Trips and during Modeling-Based Learning Cycle (야외지질답사 및 모델링 기반 순환 학습에서 학생들이 그린 그림의 목적과 기능에 대한 이해)

  • Choi, Yoon-Sung
    • Journal of the Korean earth science society
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    • v.42 no.1
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    • pp.88-101
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    • 2021
  • The purpose of this study was to qualitatively examine the meaning of students' drawings in outdoor classes and modeling-based learning cycles. Ten students were observed in a gifted education center in Seoul. Under the theme of the Hantan River, three outdoor classes and three modeling activities were conducted. Data were collected to document all student activities during field trips and classroom modeling activities using simultaneous video and audio recording and observation notes made by the researcher and students. Please note it is unclear what this citation refers to. If it is the previous sentence it should be placed within that sentence's punctuation. Hatisaru (2020) Ddrawing typess were classified by modifying the representations in a learning context in geological field trips. We used deductive content analysis to describe the drawing characteristics, including students writing. The results suggest that students have symbolic images that consist of geologic concepts, visual images that describe topographical features, and affective images that express students' emotion domains. The characteristics were classified into explanation, generality, elaboration, evidence, coherence, and state-of-mind. The characteristics and drawing types are consecutive in the modeling-based learning cycle and reflect the students' positive attitude and cognitive scientific domain. Drawing is a useful tool for reflecting students' thoughts and opinions in both outdoor class and classroom modeling activities. This study provides implications for emphasizing the importance of drawing activities.

Development and Applications of Multi-layered Harmony Search Algorithm for Improving Optimization Efficiency (최적화 기법 효율성 개선을 위한 Multi-layered Harmony Search Algorithm의 개발 및 적용)

  • Lee, Ho Min;Yoo, Do Guen;Lee, Eui Hoon;Choi, Young Hwan;Kim, Joong Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.4
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    • pp.1-12
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    • 2016
  • The Harmony Search Algorithm (HSA) is one of the recently developed metaheuristic optimization algorithms. Since the development of HSA, it has been applied by many researchers from various fields. The increasing complexity of problems has created enormous challenges for the current technique, and improved techniques of optimization algorithms are required. In this study, to improve the HSA in terms of a structural setting, a new HSA that has structural characteristics, called the Multi-layered Harmony Search Algorithm (MLHSA) was proposed. In this new method, the structural characteristics were added to HSA to improve the exploration and exploitation capability. In addition, the MLHSA was applied to optimization problems, including unconstrained benchmark functions and water distribution system pipe diameter design problems to verify the efficiency and applicability of the proposed algorithm. The results revealed the strength of MLHSA and its competitiveness.

A Study on the Records Management of the Ethnographic Data: Focusing on Classification and Description of the Research Data of "Cultural History of Kitchen" Project (문화기술지적 자료의 연구기록 관리 방안 연구 - "부엌의 문화사" 연구프로젝트 자료의 분류 및 기술을 중심으로 -)

  • Yoon, Taek-Lim;Choi, Jung-Eun
    • Journal of Korean Society of Archives and Records Management
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    • v.12 no.2
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    • pp.71-91
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    • 2012
  • This article attempts to examine the definition and categories of research records in order to include ethnographic data into research records by comparing the laboratory records with the ethnographic data produced in the field work. And it discusses the records management task of ethnogrpahic data using the field work data collected in the research project of 'Cultural History of Kitchen' which was carried out by one of the authors from 2002 to 2005. The authors draw out the classification of laboratory records from the previous studies on research records, apply it to the ethnographic data and illustrate the new classification and description of research records reflecting the features of ethnographic data. Doing so, the authors expand the concept of research records and provide a case study of research records management based on the collaboration between the researcher and the archivist. Ultimately this study will be a footstep toward construction of community archives and everyday life archives since the records for those archives may be as diverse as the research records based on the ethnographic data from the research project of 'Cultural History of Kitchen'.

A Study on Analysis of Research Data Repository in Humanities and Social Sciences (re3data를 기반으로 한 인문사회 RDR 연구)

  • Cho, Jane;Park, Jong-Do
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.30 no.2
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    • pp.69-87
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    • 2019
  • As the discussions on sharing research data prevail by the chance of the inauguration of the International Open Data Charter, research support organizations in the United States, the United Kingdom, and Japan are encouraging researchers to deposit their findings in a credible repository. Humanities and social sciences field, in which research data sharing culture and storage infrastructure are immature compared to life science and natural science, also needs to establish and operate a reliable storage infrastructure to guarantee the continuous access and utilization of data. This study analyzed the overall operational status of 305 subject repositories registered in re3data for the humanities and social sciences and clustered them according to the operational level using 5 indicators. As a result, 70% of the population were identified as universal clusters, and 20% of the excellent cluster was found to have the largest number of linguistic fields and the German-operated. In addition, this study confirmed through correspondence analysis that there is a relation between the sub-theme fields of humanities and social sciences and the types of data to be archived. The history and art domians are related to images, and social studies are related to statistical data. Linguistics has also been analyzed to be related to audio, plain text, and code.

An Investigation into the Secondary Science Teachers' Perception on Scientific Models and Modeling (과학적 모델과 모델링에 대한 중등 과학 교사의 인식 탐색)

  • Cho, Eunjin;Kim, Chan-jong;Choe, Seung-urn
    • Journal of The Korean Association For Science Education
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    • v.37 no.5
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    • pp.859-877
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    • 2017
  • The purpose of this study is to probe secondary science teachers' perception on scientific models and modeling. A total of 50 experienced science teachers were surveyed with 10 open-ended questions about several aspects of models and modeling: definition, examples, purpose, multiplicity, changeability, design/construction, evaluation and beliefs in the use of models and modeling as a teaching tool. The analysis of the data shows the following results: 1) understanding of models and modeling held by a majority of experienced secondary science teachers was far from that of experts as they concentrated on a model's superficial, representative, and visual functions, 2) when it comes to their view toward the use of a model, a model does not remain in the stage of 'doing science' but in the stage of being a subsidiary teaching tool for the teacher's explaining and the students' understanding of scientific concepts, 3) the subjects they majored in made meaningful differences in their contextual understanding of models and modeling, 4) though most of the teachers acknowledged the importance of teaching about models and modeling, even a lot of them showed a negative position toward the opinion that they are willing to apply modeling to their classes. Implications of the results were discussed in terms of intervention in order to enhance secondary science teachers' understanding and pedagogical content knowledge of models and modeling.

Aging and Research Performance of the Government-funded Research Institutes in the Field of Science and Technology (과학기술분야 정부출연연구기관의 평균연령 증가 추세가 연구성과에 미치는 영향)

  • Kim, Seung Tai;Jung, Su Hyeon;Lee, Kijong
    • Journal of Technology Innovation
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    • v.25 no.3
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    • pp.25-50
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    • 2017
  • Declining research competitiveness and inefficiency are constantly being raised in the National Assembly and the media for the Government-funded Research Institutes(GFRIs), which are highly dependent on government funding. These external stakeholders point to the workforce aging of the GFRIs as one of the main causes of inefficiency. They insist that the aging leads to an increase in labor costs, a discontinuity in research, a decrease in employment of new researchers, and a decrease in research competitiveness. However, the GFRIs argue that the aging is a natural phenomenon due to an increase in the age of recruitment, and even if there is an side effect, it is extremely small or even vice versa. It is interesting that there is no empirical study identifying the correlation between the workforce aging and the research performance of the GFRIs, despite the discussion. This study tracked and analyzed the changes of the research performance and the workforce for the five years from 2011 to 2015, and tried to demonstrate the correlation between the workforce aging and the research performance. As a result, we confirmed that there is an inverted U-type correlation between the aging and the papers, one of the research performance, and that the optimal age is 44.96 years. Also, we could not find any correlation between the aging and the patents.

A study on the Development of Physics Education Program for Foreign Students of Natural Science and Engineering College in Korea (이공계 대학의 유학생을 위한 물리교육 프로그램 개발 연구)

  • Kim, Soocheol
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.9 no.9
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    • pp.1-16
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    • 2019
  • This study was carried out to develop a physics education program for foreign students of university in Korea to improve their ability to major in the field and to prevent them from becoming dropout. The subjects of the study are five Chinese students attending a natural science and engineering college. Prior to the development of the physics education program, the researchers developed basic physics textbooks for the foreign students and questionaries for diagnosis and summative evaluation, and utilized them to apply a total of seven classes. After the application of the classes, the results of the student's diagnosis and summative evaluation, the teacher's diaries, the observer's diaries, and the transcripts were analyzed by triangulation method. In addition, Nvivo12 was used for the analysis of the teacher's and observer's diaries to help with qualitative analysis. The results of the study are as follows: First, the oder and contents of physics education program for students of the natural science and engineering college were presented in detail, and basic physics textbooks and tools for diagnosis and summative assessment were developed. Second, as a result of the analysis of the diagnosis and summative assessment results of the program, the students' basic physics achievement improved by an average of 40 points due to the application of the developed program. Third, as a result of the application of the program using Nvivo12, meaningful node and actual cases were extracted. There were 10 types of nodes created such as understanding of the students, teaching method, rate of the participation, level differences, language problems, relevance to majors, curriculum and methods of education in the country of origin, cooperative learning, and interest inducement. The researcher provided suggestions on physics education methods for students of science and engineering colleges in Korea based on the related cases.

STS and the Innovation of Sociology: Focusing on Actor-Network Theory (STS(과학기술학)와 사회학의 혁신: 행위자-연결망이론(ANT)을 중심으로)

  • Kim Hwan-Suk
    • Journal of Science and Technology Studies
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    • v.1 no.1 s.1
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    • pp.201-234
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    • 2001
  • Sociology(or social science in general) is often diagnosed as in the state of 'crisis' after the collapse of socialism and the erosion of national societies because of rapid globalization. This paper introduces some recent work within science and technology studies(STS) and discusses its potentials to reinvigorate sociology. Although sociologists have rarely regarded STS as contributing to 'mainstream' issues in sociology, an increasing number of STS writers and sociologists have recently started to notice such possibilities. One main reason of this recent change is that STS is no longer merely concerned to convey substantive findings about science and technology, but instead attempts to reconstruct key notions of sociology such as 'social', 'society' and 'agency'. It is in this respect that the discussion below aims to introduce, discuss, and assess the potential contribution of some recent work of STS to sociology. In particular, it is 'actor-network theory'(ANT) that explicitly attempts to examine and suggest the ways in which STS ran help innovate sociology. One major characteristics of ANT is to impute 'agency' to things(nonhumans) unlike traditional sociology. ANT argues that if sociology studies heterogeneous relationships between humans and nonhumans instead of human relations only, it can become once again a vigorous discipline which is able to provide alternative worlds central to the basis of sociology. So this paper focuses on, not the diverse approaches of STS, the characteristics of ANT and its potential contribution to sociology. The author concludes that ANT can not only rejuvenate sociology by implicating new forms of alternative worlds but also open the possibility to contribute to the democratic reformulation of human-nonhuman relationships.

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