• Title/Summary/Keyword: Tool life

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CRISPR as a strong gene editing tool

  • Shen, Shengfu;Loh, Tiing Jen;Shen, Hongling;Zheng, Xuexiu;Shen, Haihong
    • BMB Reports
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    • v.50 no.1
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    • pp.20-24
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    • 2017
  • Clustered regularly-interspaced short palindromic repeats (CRISPR) is a new and effective genetic editing tool. CRISPR was initially found in bacteria to protect it from virus invasions. In the first step, specific DNA strands of virus are identified by guide RNA that is composed of crRNA and tracrRNA. Then RNAse III is required for producing crRNA from pre-crRNA. In The second step, a crRNA:tracrRNA:Cas9 complex guides RNase III to cleave target DNA. After cleavage of DNA by CRISPR-Cas9, DNA can be fixed by Non-Homologous End Joining (NHEJ) and Homology Directed Repair (HDR). Whereas NHEJ is simple and random, HDR is much more complex and accurate. Gene editing by CRISPR is able to be applied to various biological field such as agriculture and treating genetic diseases in human.

Life-cycle Environmental Impact Assessment of High-rise Apartments

  • Kim, Samuel;Kim, Se-Hwan;Lee, Sung
    • Architectural research
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    • v.3 no.1
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    • pp.29-36
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    • 2001
  • Concern about global environment has been increasing in recent years. Efforts to minimize the environmental impact to the globe as well as human beings have increased, especially in the late twentieth century. The study researches one of the solutions for the environmentally friendly building construction, which can contribute to sustaining the world environment. Assessment and proposals are made for high-rise apartments, one of the most popular construction types nowadays in Korea. Since the volume of high-rise apartment construction is so great, a small improvement in each building will make a great contribution. Assessments are made over the life-span of apartment buildings. A tool named EIAHA (Environmental Impact Assessment for High-rise Apartment) has been made through references from western examples, mainly in the UK. The components of EIAHA include passive design strategies, building materials, energy consumption during building operation and management/maintenance. Although the issues are on a global scale, solutions are sought on regional scale. Korean high-rise apartments are assessed with the tool and suggestions for sustainable development are made mainly for improvement of embodied energy of building materials and the life of buildings.

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Development and Evaluation of Death Education Program for Nursing Students (간호대학생을 위한 죽음교육 프로그램 개발 및 효과)

  • Kim, Soon-Hee;Kim, Dong-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.22 no.3
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    • pp.277-286
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    • 2015
  • Purpose: This study was done to develop a death education program for nursing students and evaluate the effects of the program. Methods: The education program was developed based on ADDIE model. The death education program was developed on the base of educational needs, a comprehensive review of the literature and focus group interviews and then evaluated with 53 nursing students, 27 in the experimental and 26 in the control group. Measurement was done for the meaning of life using the tool by Choi et al (2005) for attitudes concerning death, the tool Thorson and Powell (1998) revised by Kim (2006) and for attitude to end-of-life patient care, the Attitudes toward Nursing Care of the Dying Scale by Frommelt (1991) translated by Cho and Kim (2005). Results: The program consisted of five sessions: Understanding of death, Family bereavement care, Communication and End-of-life patient care, Professional role, and Ethics and legal issues There was a statistically significant difference between pretest and posttest for the meaning of life in the experimental group compared to the control group. About 82% of students in the experimental group were satisfied with the program. Conclusion: The results indicate that this program can be used to educate nursing students.

Considerations on Digital Autobiography of the Elderly in the Digital Age (디지털 자서전 연구를 위한 고려사항 - 디지털 기기에 익숙한 노년을 대상으로)

  • Joo, Seoni;Kim, Hanil
    • Smart Media Journal
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    • v.8 no.3
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    • pp.80-87
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    • 2019
  • Older generations may want a life review, a dynamic process of recall, evaluation, and aggregation, to fulfill their developmental task of "ego-integrity." Writing an autobiography is a tool for a life review based on narrative as "mode of consciousness." This study intends to find out what should be considered so that digital autobiography can fulfill its original role as a tool to achieve ego-integrity for the New Silver Generation. For this purpose, we will first examine theories about the process of ego-integrity through a life review. Then we will analyze different aspects of writing an autobiography including three characteristics of being narrative and the compositional qualities of autobiographical writing. Next, we will review the characteristics of digital narratives autobiography, and highlight some ideas to consider in the study of digital autobiographies for the New Silver Generation.

Development and Evaluation of a Self-management Mobile App for Adults with Osteoarthritis (골관절염 대상자를 위한 자기관리 모바일 앱 개발 및 효과)

  • Park, Ju Young;Son, Jung Tae
    • Research in Community and Public Health Nursing
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    • v.33 no.1
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    • pp.114-127
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    • 2022
  • Purpose: This study aimed to develop a self-management mobile app for adults with osteoarthritis based on a self-determination theory to use it as a nursing intervention tool, and to evaluate the effects of the developed mobile app on adults' basic psychological needs, indexes of osteoarthritis, self-management and quality of life. Methods: The 56 participants were randomly assigned to either the experimental group (n=28) or the control group (n=28). The participants of the experimental group used a self-management mobile app for 12 weeks after the pretest, and two posttests were taken at the end of every 6 weeks. The data were analyzed using IBM SPSS/WIN 25.0 for Chi-square test, Fisher's exact test, independent t-test, and repeated measures ANOVA. Results: Basic psychological needs, indexes of osteoarthritis, self-management, and quality of life score of the experimental group were significantly higher than those of the control group. Conclusion: Our findings suggest that mobile app intervention can support improvements in psychological needs, symptoms of osteoarthritis and quality of life in adults with osteoarthritis. It is recommended that the developed mobile app be used as a nursing intervention tool for adults with osteoarthritis in the community.

Factors Influencing the Meaning of Life for Middle-aged Women (중년여성의 삶의 의미와 영향요인)

  • Park, Geum-Ja
    • Women's Health Nursing
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    • v.8 no.2
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    • pp.232-243
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    • 2002
  • The purpose of this study was to examine factors influencing the meaning of life for middle-aged women. The subjects for the study were 190 middle-aged women who live in Busan. Data were collected from May 25 to June 20, 1999. The instruments for this study were as follows : the meaning of life scale developed by Jung D. R(1978) ; the self-esteem scale developed by Ro, E. Y, Kwon, J. H.(1997) ; the volunteer activity scale developed by Park G. J.(1999), the marital satisfaction scale developed by Choi G. Y.(1999) ; and the health status scale developed by Kim S. Y. (1991). SPSS PC+ was utilized for data analysis. Data were analysed according to frequency and percentage, mean and standard deviation, t-test, ANOVA, Sheffe' s test and Pearson' s correlation coefficients and stepwise multiple regression. The reliability of the tools was tested by Cronbach's $\alpha$ : and it showed reliability scores of 0.88(for the meaning of life tool), 0.81(for the self-esteem tool), 0.94(for the marital satisfaction tool) and 0.78(for the health status tool). The results were as follows: 1) The scores showed that middle-aged women had a moderate level of meaning of life, with a mean of 30.31 and standard deviation of 6.24 (with values ranging from 12.00 to 48.00). The scores showed that middle-aged women had a moderate levels of self-esteem, with a mean of 28.92 and standard deviation of 4.67 (with values ranging from 10.00 to 40.00). The scores showed that middle-aged women had a very low level of volunteer activity, with a mean of 0.87 and standard deviation of 0.93(with values ranging from 0.00 to 1.00). The scores showed that middle-aged women had a moderate level of satisfaction in their marriages, with a mean of 31.99 and standard deviation of 7.84(with values ranging from 12.00 to 48.00). The scores showed that middle-aged women had a moderate level of health status, with a mean of 6.63 and standard deviation of 1.57(with values ranging from 3.00 to 9.00). 2) There was a statistically significant difference of the meaning of life of middle-aged women according to their religion(F=8.930, p=.000), christian ($31.94{\pm}5.96$) had more meaning th life than buddhists ($28.40{\pm}6.23$). 3) There was a statistically significant correlations between the subject' s self-esteem and the her meaning of life(r=0.477, p=0.000), the subject' s level of volunteer activity and meaning of life(r=.428, p=.000), her level of marital satisfaction and meaning of life(r=.417, p=.000), and her level of health status and meaning of life(r=.261, p=.000) among these middle-aged women. 4) Self- esteem was the highest factor influencing the level of meaning of life in middle-aged women. 40.0% of the total variance of levels of meaning of life by was dependent on self-esteem, volunteer activity, marital satisfaction and health status. In conclusion, the higher the self-esteem and levels of volunteer activity, marital satisfaction, and health status of middle-aged women, the higher the meaning of life for them. Therefore, it is necessary to elevate levels of the self-esteem and volunteer activity, marital satisfaction and health status in order to help middle-aged women have more meaning of life.

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Cutting method of tungsten carbide material using hot machining (고온가공기법을 이용한 초경소재 가공기술)

  • 이채문;이득우;정우섭;김상기
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.04a
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    • pp.365-369
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    • 2004
  • The Advantages of hot machining are the reduction of cutting forces, tool wear, and the increase of material removal rates. In this study, a hot-machining using gas flame heating characteristics of milling by CBN tip was analyzed, and the influence of the surface temperature and the depth of cut on the tool life were investigated. The results show that hot machining of tungsten carbide-alloyed is more effective than conventional machining. In addition, some advantages obtained from hot machining, such as decrease of tool wear and cutting force, high surface quality.

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A Study on the Wear of Milling Tool and Relativity of Acoustic Emission in Cutting Process (절삭중 밀링공구의 마멸과 음향방출의 관련성에 관한 연구)

  • 윤종학;김동성
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.4 no.2
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    • pp.31-37
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    • 1995
  • This study is focused on the prediction of appropriate tool life by clarifying the correlation between progressive tool wear and AE signal. when rcutting SM45C by End mill in machining center. First of all, end mill have a problem that position of sensor sticking because it is revolution tool, but I think that it can be bained specific character according to sticking Sensor in the Vise. Consequently, the following results have been obtained; 1. Each cutting speed of feed rate over 0.1mm had a tendency to increase linearly according to the RMSAE 2. The level of AE signal at the same cutting area was more sensitive to depth of cut tharn the variation of feed rate 3. In the range of cutting duringqr about 75minqr atqr cutting speed 27m/min flankqr wear turns up aboutqr 0.21mm, aboutqr 0.29mm in the caseqr of about 65minqr at 33/min, qr hereby RMSAE increased rapidly at 0.2mm flank wear, also AE-HIT and CUM-CNTS.

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Monitoring of Chatter Vibration by Frequency Analysis of AE Signals (AE 신호의 주파수분석에 의한 Chatter 진동의 감시)

  • 조대현
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.9 no.5
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    • pp.157-164
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    • 2000
  • A machine tool generally has some serious stability problems in the form of tool chatter during the cutting process. Chatter vibration deteriorates the surface finish, reduce tool and machine life, accelerates machine tool system component wear, and may lead to an unacceptable noise sound in the working environment. In this study, the behavior of spectral density of AE signal and principal cutting force signal in order to monitor the chatter vibration in the cutting process has been investigated. From the results, the reliability of proposed monitoring method has been confirmed.

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A study on the orthogonal cutting characteristics of glass fiber reinforced plastics (복합재료의 직교 절삭가공 특성에 관한 연구)

  • 송화용;정용운;김준현;김주현
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2001.10a
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    • pp.155-160
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    • 2001
  • In the use of glass fiber reinforced plastics(GFRP) it is often necessary to cut the components, but the cutting of GFRP is often made difficult by the delamination of the compositions and short tool life. Experimental investigation was conducted to evaluate the chip formation of the glass fiber reinforced plastics during orthogonal cutting. The chip formation process, cutting force, and thrust force were studied. The chip formation processes were studied through the use of quick-stop device. Chip-tool contact areas were obtained with the use of the quick-stop device, and observed using optical microscopy after polishing. Cutting force and thrust force were measured through the use of the tool dynamometer.

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