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Sampling and Cryogenic Pulverization and Storage of Environmental Samples and Improvement of Operating Procedures in National Environmental Specimen Bank (국가환경시료은행 시료 채취, 분쇄, 저장과 개선방안 고찰)

  • Lee, Jangho;Lee, Jongchun;Kim, Myungjin;Han, Areum;Lee, Eugene;Bade, Rabindra;Kim, Minsung
    • Journal of Environmental Impact Assessment
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    • v.21 no.6
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    • pp.823-839
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    • 2012
  • Environmental Specimen Banks (ESBs) are playing pivotal role in monitoring the effect of environmental pollution on the ecosystem based on the retrospective analysis of the representative samples collected regularly and stored in cryogenic condition. In Korea, National Environmental Specimen Bank (NESB) was established in 2009 and the standard operating procedures (SOPs) for sampling, and cryogenic milling and storage had been prepared during 2007-2010. Since then, the tentative SOPs for the seven kinds of specimens (shoots of Red Pine (Pinus densiflora) and Korean Pine (Pinus koraiensis), leaves of Mongolian Oak (Quercus mongolica) and Zelkova Tree (Zelkova serrata), eggs of Feral Pigeon (Columba livia var. domestica), muscles and organs of Common Carp (Cyprinus carpio), and Freshwater Bivalve (Unio (Nodularia) douglasiae)) have been put to test in the field and laboratory as well against the practicality and feasibility. The SOPs were improved by reflecting the findings from the research and the following discussion regarding the selection of specimen (Feral Pigeon suffering from a control management), sample size (a problem of decreasing number of sampling trees related to increasing sampling time) and period (a problem related to a bud growth), and sampling methods etc.. In addition, barcoding system for the management of the specimen information, and monitoring system of the cryogenic storage to regulate the optimum temperature and the liquid nitrogen level were also developed for the efficient and effective control of the samples. Lastly, the safety guide and emergency protocol were augmented to guarantee a safe work environment with the cryogenic facility. These improvements of the SOPs are expected to contribute to more stable operation of the NESB.

An Effect of Revolutions Per Minute (r.p.m) in the Noise Characteristics (기계소(機械騷) 음(音)과 회전(回轉) 속도(速度))

  • Cha, Bong-Suk
    • Journal of Preventive Medicine and Public Health
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    • v.10 no.1
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    • pp.94-101
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    • 1977
  • Noise pollution, both in the environment and in the workplace, has been recognized as a major health hazard -one that can impair not only a person's hearing but also his physical and mental well-being. As industrialization progresses, the prevalence rate of occupational diseases is increasing, especially hearing loss, which has the highest prevalence rate among the occupational diseases. The major cause of noise is the construction of various large industries without any regulation of noise sources. Therefor, we must establish an enactment to control mechanical noise sources. as soon as possible. For the purpose of controlling the noise source, we must have exact data about such things as the sound level, the frequency of the peak sound and the revolutions per minute (r.p.m.) of the machine (a measure of the power of its motor). This study was undertaken in order to define the noise characteristics, the power of the machine's motor, the change of the sound level and the peak sound as the r.p.m. increases, and the permissible exposure time. The sample size of this study was 74 machines at 11 plants in 6 industries. The results are as follows; 1. The breakdown of the types of mechanical noise noted was : 63.6% continuous normal sound, 26.9% intermittent sound, 4.7% continuous repeating sound and 4.6% impulsive sound. 2. With respect to the type of industry, the overall sound level was the highest in the mechanical industry, with $103.8{\pm}2.8dB(A)$, and lowest in the textile industry, with $89.2{\pm}1.43dB(A)$. 3. With respect to the type of machine, the highest sound level was 124 dB(A) caused by Gauzing(II), in the mechanical industry, and the lowest was 76 dB(A) caused by Attachment (Jup Chack) (I) in the timber industry. 4. The shortest permissible exposure time to Gauzing(II) in the mechanical industry was less than 15 minutes. 5. Among 74 machines, 68.2% of the peak sound was situated in the high frequency range (52.7% at 2 KHz, 4.1% at 4 KHz and 1.4% at 8 KHz). 41.8% of the peak sound was in the middle frequency range (4.1% at 250Hz, 14.8% at 500Hz and 22.9% at 1KHz). 6. If one machine had two motors or more, the peak sound was shifted to the low frequency range. 7. As the r.p.m. increased, the overall and peak sound levels were increased without any change of the frequency of the peak sound. 8. Whenever the machines had the same kind and the same r.p.m., the overall and peak sounds were changed by the physicochemical characteristics of the raw materials and the management.

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Confidence Bounds following Adaptive Group Sequential Tests with Repeated Measures in Clinical Trials (반복측정자료를 가지는 적응적 집단축차검정에서의 신뢰구간 추정)

  • Joa, Sook Jung;Lee, Jae Won
    • The Korean Journal of Applied Statistics
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    • v.26 no.4
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    • pp.581-594
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    • 2013
  • A group sequential design can end a clinical trial early if a confirmed efficacy or a futility of study medication is found during clinical trials. Adaptation can adjust the design of clinical trials based on accumulated data. The key to this methodology is considered to control the overall type 1 error rate while maintaining the integrity of clinical trials. The estimation would be more complex and the sample size calculation will be more difficult if the clinical trials have repeated measurement data. Lee et al. (2002) suggested a repeated observation case by using the independent increments properties of the interim test statistics and investigated the properties of the proposed confidence interval based on the stage-wise ordering. This study extend Lee et al. (2002) to adaptive group sequential design. We suggest test statistics for the adaptation as redesigning the second stage of clinical trials and induce the stage-wise confidence interval of parameter of interests. The simulation will help to confirm the suggested method.

A Study on the Health Care Management of Industries in Seoul (서울지역 산업장의 보건관리)

  • Jung, Yeun-Gang;Park, Shin-Ae;Lee, Na-Mi;Yoon, Soon-Young;Kim, Young-Im;Wang, Myoung-Ja;Lee, Soon-Nam;Kim, En-Hee;Ko, Young-Ae
    • Research in Community and Public Health Nursing
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    • v.4 no.1
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    • pp.5-13
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    • 1993
  • The objective of this study was to analyze the status of health examination, and the health care management of industries in Seoul. This will provide effective industrial health care services. 46 industries were selected as a sample, and were given self administered questionnaire developed by the academic affairs of community health nursing. The results of this study are as follows: (1) The general characteristics of industries: The greater part of the industries were manu facturing companies, 300-900 workers, in a one shift system. (2) The general characteristics of health man ager: 96% of the companies had industrial nurses and the larger industries had comprehensive health managers. 90% of the industrial nurses were full-time employees and 77% of the industrial physician were part time employees. 80% of the industrial physician were age 50 or older, while 59% of the industrial nurses were 25-29 years of age. (3) Health examination and follow up care: The proportions of the workers who took general health examination was 94%. Of those, 12% took secondary examinations. In secondary examinations, 36% were evaluated at the C-grade, 20% were evaluated at the D-grade. The proportion of the workers who were required to take special examination were 29% and of that, the proportion of the workers who actually took the examination was 88%. 85% of the workers who were recommended for follow up cares were given follow up care while working. The physical agents among the special examination were done the most frequently to detect the examination effects. (4) Health care services: Industrial nurses performed health examination most frequently and health education was done the least. There were significant differences in health care services according to the size of the industries. Companies with 300 workers or less had higher health care services than other groups. The three primary reasons of health care management and examinations of workers are: First, industrial nurses are requires to accumulate professional knowledge and experience through continuos' activities. Second, systematic and concert examination for industrial workers should be performed periodically. Third, it needs developing health education strategies that are important workers for health promotion in industries.

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The Pad Recovery as a function of Diamond Shape on Diamond Disk for Metal CMP (Metal CMP 용 컨디셔너 디스크 표면에 존재하는 다이아몬드의 형상이 미치는 패드 회복력 변화)

  • Kim, Kyu-Chae;Kang, Young-Jae;Yu, Young-Sam;Park, Jin-Goo;Won, Young-Man;Oh, Kwang-Ho
    • Journal of the Microelectronics and Packaging Society
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    • v.13 no.3 s.40
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    • pp.47-51
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    • 2006
  • Recently, CMP (Chemical Mechanical Polishing) is one of very important processing in semiconductor technology because of large integration and application of design role. CMP is a planarization process of wafer surface using the chemical and mechanical reactions. One of the most important components of the CMP system is the polishing pad. During the CMP process, the pad itself becomes smoother and glazing. Therefore it is necessary to have a pad conditioning process to refresh the pad surface, to remove slurry debris and to supply the fresh slurry on the surface. A conditioning disk is used during the pad conditioning. There are diamonds on the surface of diamond disk to remove slurry debris and to polish pad surface slightly, so density, shape and size of diamond are very important factors. In this study, we characterized diamond disk with 9 kinds of sample.

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A Study on Self-Leadership and Job Involvement of Multicultural Family Home-Visit Instructors (다문화가족 방문교육지도사의 셀프리더십과 직무몰입에 관한 연구)

  • Chae, Jin-Young;Kim, Hera;Hwang, Hae Shin;Kwon, Ki Nam;Kang, Bogjeong;Suh, Joo Hyun
    • Korean Journal of Child Studies
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    • v.37 no.6
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    • pp.83-94
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    • 2016
  • Objective: The purpose of this study was to investigate differences in self-leadership and job involvement based on the education levels, majors, and teaching experiences of multicultural family home-visit instructors and the influence of self-leadership on job involvement. Methods: 668 home-visit instructors participated in the online survey from 140 multicultural family support centers in Seoul, 6 metropolitan cities, 9 provinces, and other cities and counties. Data were analyzed through frequency, percentages, Pearson's correlations, one-way ANOVA, $Scheff{\acute{e}}$ post-hoc test, and stepwise multi-regression using SPSS 21.0. Results: The main findings are as follows. First, instructors who were high school graduates had significantly higher scores in self-leadership than the other groups. There was only a significant difference in self-reward of self-leadership based on their majors. There were no significant differences in job involvement based on the education level and major. The greater their home-visit teaching experiences, the higher their scores in self-leadership and job involvement. Second, the stepwise multiple regression model showed that self-expectation, self-goal setting, constructive thinking, and rehearsal of self-leadership explained 49% of the total variance in job involvement. Conclusion: Even though the high school graduates had significantly higher scores in self-expectation, rehearsal, and constructive thinking of self-leadership than the other groups, over-generalization should be avoided because the sample size was relatively small. Based on the finding that greater home-visit teaching experiences was associated with higher self-leadership and job involvement, it would be necessary to improve working condition to prevent instructors from changing jobs. These findings stress the importance of providing opportunities for home-visit instructors to develop leadership, thus improving job involvement.

The Research Trends in Fundamental Nursing - Based on the Analysis of Journal of Korean Academy of Fundamental Nursing - (기본간호학 연구동향 - 기본간호학회지 논문분석을 기반으로 -)

  • Jeong Ihn-Sook;Kang Kyu-Sook;Kim Kyung-Hee;Kim Keum-Soon;Kim Won-Ock;Byun Young-Soon;Sohng Kyeong-Yae;Son Yeong-Hee;Yang Sun-Hee;Jo Hyun-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.8 no.2
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    • pp.132-146
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    • 2001
  • Purpose: This study was to analyze the trends and content of all the research (171 research papers) published in the Journal of Fundamentals of Nursing from 1994, when it began to 2000 using an objective tool developed by the researches, and to identify the direction for the future research in Fundamentals of Nursing. Method: Research published in the Journal of Fundamentals of Nursing from 1994 were reviewed. Result: Most of research (94.2%) was non-degree based and funded research was very limited. The average number of researchers per research study was 2.2 and collaborative research has been gradually increasing. The total number of key words was 331 and the average was 2.6 per research. The major key words were not different from other nursing departments and included home care nursing (10 times), health promotion (8 times), self-care (7 times). self-efficacy (7 times), and homo-dialysis (6 times). Eighty seven percent of the research was quantitative research. and there were very few qualitative studies. Considering theory level, it was found that 40% were factor related research For study design, non-experimental studies were most frequent (66%), and the rate, especially of surveys, has remarkably decreased. Selection of subjects by convenience sampling, was most frequent and there were very few studies that provided the rationale for the calculation of sample size. The major subjects of study were patients (44.8%) with various diagnoses. The subjects usually gave oral consent to take part in that study. Giving information (46.9%) and exercise (26.5%) were common nursing interventions, and physiological indices (16.5%). vital signs (10.3%), physical functioning (8.2%), level of knowledge/skill (7.2%) and level of activity (6.2%) were frequently measured as outcome. Variables questionnaires were the major approach used to collect data, and 57.8% of the research provided the Cronbach alpha to guarantee internal consistency of study instruments. Data were analyzed with computerized statistical packages using, ANOVA (42.0%), T test(39.5%), and chi-square test. For the last seven years, nursing research in Fundamentals of Nursing has gradually improved in both quantify and quality. Conclusion: It was difficult to find any uniqueness or difference compared to other departments of nursing. In fact, because the history of the Journal of Fundamentals of Nursing is rather short, we can expect that there will be further improvement in qualify and content in the future.

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Mobi-kids: A Case-control Study Protocol on Electromagnetic Field Radiation Exposure from Telecommunication and Brain Tumors in Children and Adolescents (모비키즈: 통신전자파 노출과 어린이청소년의 뇌종양에 관한 환자 -대조군 연구 프로토콜)

  • Choi, Kyung-Hwa;Kim, Dong-Seok;Lee, Jung-il;Ra, Young-Shin;Phi, Ji Hoon;Ahn, Young Hwan;Kwon, Jong Hwa;Lee, Ae-Kyoung;Choi, Hyung-Do;Ha, Mina
    • Journal of Environmental Health Sciences
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    • v.41 no.3
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    • pp.182-190
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    • 2015
  • Objectives: To introduce a protocol of Mobi-kids study which was aimed to examine an association between radiofrequency (RF) radiation exposure by mobile phone use and brain tumor risk in children and adolescents. Methods: The Mobi-kids study was a multinational matched case control study using a standardized protocol with the number of subjects targeted about 1,000 cases and 2,000 controls aged 10 to 24. In Mobi-Kids Korea, the source population was restricted to Seoul, Incheon, and Gyeonggi-do province. Eligible cases of primary brain tumor (glioma, meningioma, and others) were diagnosed from January 2012 to June 2015. Eligible controls were appendicitis patients operated during the study period. Two controls were matched on age, gender, and study region for 1 case. Information about pattern and history of mobile phone use and other covariates were obtained by face to face interview by trained interviewer. The Mobi-kids study has been involved in Mobi-expo as a validation study about mobile phone use, XGridmaster to localize tumor in the brain for RF energy calculation, and histological review for validation of diagnosis. Results: The Mobi-kids was the first and largest study in children and adolescents to estimate risk of brain tumor in association with the RF energy absorption in the brain estimated by mobile phone use. Forty-six-cases and 54 controls were collected as of September 2014 in Korea. Conclusions: The meaningful results of the study were expected because of the largest sample size, high validity of EMF exposure assessment as well as the susceptible study populationof children and adolescents.

The Analysis of Statistics and Scientific Inquiries Types in Korea Astronomy and Space Science Institute Q&A Service (한국천문연구원 질문상자의 통계 및 과학탐구 질문유형 분석)

  • Yim In Sung;Sung Hyun Il;Sohn Sangmo;Ahn Young Sook;Kim Bong Gyu;Choe Seung-Urn
    • Journal of the Korean earth science society
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    • v.26 no.6
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    • pp.551-559
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    • 2005
  • The Q&A service of the official Korea Astronomy and Space Science Institute (KASI) webpage was installed in 2000 and have been actively used since then. In this paper, we analyze the questions asked through the Q&A service and the number of inquiries with the aid of statistical methods. We also study the contents of the questions. Specifically, we have created statistics of questions and inquiries that go monthly and yearly, and have developed categories to analyze the characteristics of questions in regards to their cognitive aspects. Each question is categorized into two elements based on their recognitive aspect: science knowledge or science study. Each element also has sub-categories that help readers understand the characteristics of the questions. For the analysis, we used a sample consisted of questions from July to December, 2004. Through this study, we achieved a better understanding of the questions asked by the Q&A service. We are planning to improve the quality of the Q&A service by extending the size of the FAQ(frequently asked questions). Throughout this study, we find that the number of questions are increasing with time, and the overall quality of the questions is improving. As we expect the number of people using our Q&A service to increase and the questions to get more difficult to answer, development of improved content is required.

A Study on the Classification of Student's Bluffing on Geographical Terms (지리 용어에 대한 학습자의 블러핑(Bluffing) 유형에 관한 연구)

  • Jang, Eui-Sun
    • Journal of the Korean Geographical Society
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    • v.49 no.4
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    • pp.615-632
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    • 2014
  • This study aims to explore 'bluffing', one of the most important topics in order to ensure the objectivity, validity, reliability of scoring of constructed-response items. The author identifies the conception of bluffing, and classifies major types of bluffing on the basis of previous studies on the theoretical level. Next, the author analyzes empirically the bluffing strategies and types of learners on key terms of Korean Geography subject. Compared with the existing research reports, the result of this study shows a significantly lower average bluffing score. On the other hand, it is consistent in results of previous studies reported that average bluffing score is similar between genders and that those students who got highest grades did least bluffing. Actually bluffing types are classified into four categories: 'repeating the question' type, 'depending on a well-known or existing knowledge' type, 'applying some basic concepts regardless of understanding' type, and 'inducing scorer's basic beliefs' type. Some comments and suggestions are as follows. First, it is necessary to continue researches of the relations among bluffing and age, gender, grade, intelligence and learning styles. Second, it is required for scorers who score constructed-response items to develop and supply the scoring guide including analysis contents of bluffing types and cases, and increase opportunity for training. Third, we need to inquire the domain-specific bluffing types in geography subject based on the generalizable sample size.

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