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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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The Research Trends of Papers in The Korean Journal of Occupational Health Nursing (산업간호학회지 논문의 연구동향 분석)

  • Lim, Kyung-Kee;Park, Kyung-Min
    • Korean Journal of Occupational Health Nursing
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    • v.10 no.2
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    • pp.142-152
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    • 2001
  • This study examined all the papers published in the Journal of Occupational Health Nursing from 1991 to May 2000 based on an objective frame of evaluation. The purpose of study is to prospect the trend of occupational nursing research and to provide an optimal direction for future occupational nursing service. The results of total 94 studies were analyzed as follows. 1. The number of papers published in 1991-1992, 1993-1995, 1996-1997 was not significantly increased. However, the number of papers were obviously increased after 1998. 2. In the design of research, survey studies were definitely dominant. But, they are gradually decreasing and experimental studies are increasing. 3. In the fields of research, health problems, health risk factors and health awareness were higher than others. Occupational health nurse's task and job satisfaction were main areas of research until the middle of 1990's. However, after then, not only health problem, risk factor and awareness of health but also health promotion and preventive health behavior are increasing in the research areas. 4. The collaborative researches have gradually increased and the type of author has been varied. The number of researches completed by funds was undertaking only 3 among the total 94. 5. In the research analysis, except for case studies and literature studies, the research subjects have been shifted from the occupational health nurses to the industrial workers, and more diversified. The sample size has been enlarged and the major place of the study is industry. The questionnaire was used in many studies as instrument for data collection and measurement. But, complementary methods of diverse instruments have been increased. The method of data analysis has obviously showed some changes moving from descriptive statistics to inferential and advanced statistics. 6. The ways of nursing intervention have prominently diversified in experimental studies. The contents of case studies were mainly focused on the health management programs and activities in industry. The research concepts and the contents of literature study were also changed progressively in various way. Based on the above findings, conclusions are extended to the following discussion: Since the Korean Academic Society of Occupational Health Nursing was instituted in 1990, the researches of occupational health nursing have shown an acute methodological development in both quantity and quality. However, they were considered still in the lack of research verifying the effects of nursing intervention program. Also, the development of nursing intervention and nursing theory lacked. Therefore, more empirical researches are strongly needed to utilize the field of occupational health nursing in Korea Researchers are also encouraged to exert more efforts to get research funds.

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Development of PDA-Based Software for Forest Geographic Information (PDA기반의 산림지리정보 소프트웨어 개발에 관한 연구)

  • Suk, Sooil;Lee, Heonho;Lee, Dohyung
    • Journal of Korean Society of Forest Science
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    • v.96 no.1
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    • pp.7-13
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    • 2007
  • This study was done to develop PDA based application system for forest geographic information with GPS. The major results obtained in this study were as follows. A PDA based application program was developed to work on $Microsoft^{TM}$ PocketPC 2002 and 2003 operating system. The screen of PDA displays a 1:25,000 digital topographical map adopted DXF format converted from PC, and the map data with 1:2,500 to 1:30,000 on PDA can be zoomed in or out to five levels. Current position and navigating path received from GPS can be displayed on the screen and be saved in PDA. Information selected among layers of digital topographic map in DXF format can be converted into binary files which can be used on forest geographic information software. This can compress DXF files to 90% in size, and the processing speed of PDA was improved. The forest geographic information management system can be used to manage sample plots on which forest inventory is done, with the help of the sub-menus and grid index values with position information received from GPS. Forest workers can in quire forest geographic information such as forest type, location, forest roads, soil erosion control dams using forest geographic information management system in the field. The forest geographic information management system can provide current position and mobile path information to people who enjoy forest related activities like mountain-climbing, sightseeing, and visiting to historic spots.

The Ratio-Based N Staging System Can More Accurately Reflect the Prognosis of T4 Gastric Cancer Patients with D2 Lymphadenectomy Compared with the 7th American Joint Committee on Cancer/Union for International Cancer Control Staging System

  • Hwang, Sung Hwan;Kim, Hyun Il;Song, Jun Seong;Lee, Min Hong;Kwon, Sung Joon;Kim, Min Gyu
    • Journal of Gastric Cancer
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    • v.16 no.4
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    • pp.207-214
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    • 2016
  • Purpose: The utility of N classification has been questioned after the 7th edition of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) was published. We evaluated the correlation between ratio-based N (rN) classification with the overall survival of pathological T4 gastric cancer patients who underwent D2 lymphadenectomy. Materials and Methods: We reviewed 222 cases of advanced gastric cancer patients who underwent curative gastrectomy between January 2006 and December 2015. The T4 gastric cancer patents were classified into four groups according to the lymph node ratio (the number of metastatic lymph nodes divided by the retrieved lymph nodes): rN0, 0%; rN1, ${\leq}13.3%$; rN2, ${\leq}40.0%$; and rN3, >40.0%. Results: The rN stage showed a large down stage migration compared with pathological T4N3 (AJCC/UICC). There was a significant difference in overall survival between rN2 and rN3 groups in patients with pT4N3 (P=0.013). In contrast, the difference in metastatic lymph nodes was not significant in these patients (${\geq}16$ vs. <15; P=0.177). In addition, the rN staging system showed a more distinct difference in overall survival than the pN staging system for pathological T4 gastric cancer patients. Conclusions: Our results confirm that rN staging could be a good alternative for pathological T4 gastric cancer patients who undergo D2 lymphadenectomy. However, before applying this system to gastric cancer patients who undergo D2 lymphadenectomy, a larger sample size is required to further evaluate the usefulness of the rN staging system for all stages, including less advanced stages.

Relationship between Genetic Polymorphisms in MTHFR (C677T, A1298C and their Haplotypes) and the Incidence Of Breast Cancer among Jordanian Females - Case-Control Study

  • Awwad, Nemah;Yousef, Al-Motassem;Abuhaliema, Ali;Abdalla, Ihab;Yousef, Muhammad
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.12
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    • pp.5007-5011
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    • 2015
  • Background: Breast cancer is a major cause of morbidity and mortality in Jordan and worldwide. Abnormality of DNA methylation is a possible mechanism for the development of cancer. Methylenetetrahydrofolate reductase (MTHFR) is involved in DNA methylation. Our aim was to study the association between genetic polymorphisms of MTHFR at two sites (C677T and A1298C) and their haplotypes and the risk of breast cancer among Jordanian females. Materials and Methods: A case-control study involving 150 breast cancer cases and 150 controls was conducted. Controls were age-matched to cases. Polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP) technique and sequencing were conducted to determine the genotypes. Results: There was a significant difference in genotype frequency of C677T in the 41-60 year age category [cases: CC (37.4%), CT (49.5%) and TT (13.2%); controls: CC (56.3%), CT (35.6%) and TT (8%), p= 0.04; $OR_{TT\;vs.\;CC}$: 2.5, 95% CI: (0.9-6.9); $OR_{at\;least\;on\;T$: 2.1, 95%CI: (1.2-3.9)]. There was no significant difference in genotype frequency of A1298C between cases and controls [cases: AA (46.6%), AC (41.8%) and CC (11.6%); controls: AA (43%), AC (47.4%) and CC (9.6%); p= 0.6]. There was a significant difference of MTHFR genetic polymorphism haplotypes among breast cancer cases and controls [cases/control: CA: 38.3/45.4%; CC: 28.9/25.2%; TA: 29.2/21; TC: 3.6/8.3; p value= 0.01; $OR_{TA\;vs.\;CA}=1.6$; 95% CI (1.1-2.5); p= 0.02]. Conclusions: Genetic polymorphism of MTHFR C677T may modulate the risk of breast cancer especially in the 41-60 year age group. Additionally, TA haplotype amends the risk of breast cancer. Future studies with a larger sample size are needed to validate the role of MTHFR genetic polymorphisms in breast cancer.