• Korean Journal of Materials Research
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• v.17 no.1
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• pp.25-30
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• 2007

The in-situ scanning electron microscopy observation of real-time hillock evolution in pure hi thin films on glass substrate during Isothermal annealing was analyzed quantitatively to understand the compressive stress relaxation mechanism by focusing on the effect of Mo interlayer between Al film and glass substrate. There is a good correlation between the hillock-induced stress relaxation by in-situ scanning electron microscopy observation ana the measured stress relaxation by wafer curvature method. It is also clearly shown that the existence of Mo interlayer plays an important role in hillock formation probably due to the large difference in interfacial diffusivity of Al films.

• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.405-415
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• 2005

This study was to investigate firstly a way of promoting health through increasing kimchi ingestion by means of analyzing the points to be improved on the state of taking kimchi, the traditional Korean food, the degree of kimchi likings and the problems of the kimchi on the market, and secondly the other way of having our favorite age-old kimchi quality improved as well as making kimchi inherited by means of collecting useful related materials via questionnaire survey intended for 316 housewives of $20{\sim}50$ years old who lived in Seoul. In the degree of preferences, 92% of them liked kimchi, being considered that higher the age, higher the nostalgia with perception of traditional food. On the problems to be improved of the kimchi on the market, the most answers, 48.73%, said that the hygiene was worrying, indicating that the most overriding problem to be improved in the kimchi on the market was all-out sanitary management. On the thinking of kimchi, the feeling of that the kimchi was the most Korean-like was predominant.

• Journal of Korean Dental Hygiene Science
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• v.3 no.1
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• pp.45-50
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• 2020

A total of nine oral health educators for 17 persons with developmental disabilities conducted oral health education once a week for four weeks. The oral health educators provided oral health knowledge education and individual toothbrushing teachings. The developmentally disabled people in their 20s and 30s conducted oral health education without a guardian. Ten people who completed all the four pieces of training had no significant improvement in the toothbrushing method and the recommended number of toothbrushing sessions a day, as well as a lack of growth in oral health knowledge. However, 58.8% of the individuals expressed satisfaction with the oral health education program, whereas, 52.9% expressed the desire for a re-education. Although the ratio of teachers to students was 1:2, and the oral health education conducted four times, it was insufficient to promote a successful oral health behavior or knowledge for people with developmental disabilities. Therefore, as a suggestion, oral health education for people with developmental disabilities ought to proceed with their guardians to promote the success of the training.

• Journal of Korean Academy of Dental Administration
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• v.7 no.1
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• pp.10-20
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• 2019

Korean dental hygienists perform more tasks in dental clinics than are described in the law. The purpose of this study was to investigate the actual work of Korean dental hygienists in dental clinics using an observational study design. Two dental hygienists observed and recorded the work performed in 1 day from the time of commencement to the time of leaving work by 18 dental hygienists working in the dental clinic in a single area. Data management, prevention of infection, counseling, calculus removal, radiography, assistance of fixed orthodontic treatment, assistance of fixed prosthetic treatment, and preparation for implant surgery were recorded. Among the tasks that take more than 1 min, the most time-consuming tasks were document management, infection control, consultation, calculus removal, preparation for implant surgery, assistance of orthodontic treatment, and assistance of fixed prosthetic treatment. Korean dental hygienists are performing various tasks, such as infection control, dental hospital/clinic management, oral disease prevention, and dental treatment assistants.

• Journal of Korean Academy of Dental Administration
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• v.11 no.1
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• pp.47-53
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• 2023

This study aims to analyze the research trends of the Journal of Korean Academy of Dental Administration and identify the characteristics of the journal. The research was based on 10 academic journals from 2013 to 2022 and related documents. The type of paper, research method, statistical analysis, topic classification, and research subject of 65 papers were extracted and categorized. As a result, the distribution of paper types was as follows: research articles accounted for 83.2%, review articles for 12.3%. In terms of research methods, questionnaire surveys were used in 46.2% of the papers, literature reviews in 23.1%, and national data analysis in 7.7%. Research topics included dental manpower at 20.0%, infection control at 7.7%, dental information at 6.2%, patient safety at 6.2%, and oral health care quality at 6.2%. 72.3% of the papers were quantitative studies, and the majority of research subjects were dental hygienists or dental hygiene students, accounting for 26.2% of the total. The Journal of Korean Academy of Dental Administration covers topics such as dental healthcare marketing, dental healthcare organization and management, dental healthcare information, dental healthcare policy, dental healthcare insurance, dental healthcare quality management, patient safety, medical disputes, and infection control. The authors are also contributed by a variety of dental personnel, including dentists, dental hygienists, and dental technicians.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.4
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• pp.790-805
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• 1988

Static strength and fatigue life scattering of glass fiber reinforced epoxy composite materials has been studied. Normal, lognormal, two-parameter and three-parameter Weibull distribution functions are used for strength and one-stress fatigue life distribution. The value of mean fatigue life is analysed using mean fatigue life, mean log fatigue life and expected value of 2 and 3-parameter Weibull distribution functions. Modification on non-statistical cumulative damage models is made in order to interpret the result of two-stress level fatigue life scattering. The comparison results show that 3-parameter Weibull distribution has better predictions in static strength and one-stress level fatigue life distributions. However, no advantage of 3-parameter Weibll distribution is found over 2-parameter Weibull distribution in two-stress level fatigue life predictions. It is found that two-stress level fatigue life prediction by the expanded equal rank assumption is close to the experimental data.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.2
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• pp.1-8
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• 2011

5-axis NC machining has a good advantage of the accessibility of tool motion by adding two rotary axes. It offers numerous advantages such as expanding machining fields in parts of turbo machineries like impeller, propeller, turbine blade and rotor, reasonable tool employment and great reduction of the set-up process. However, as adding two rotary axes, it is difficult to choose suitable machining conditions in terms of cutter path and cutter posture at a cutter contact point. Therefore in this paper, it is proposed to decide suitable machining condition through an experimental method such as adopting various cutter paths, cutter postures types. Also, in order to increase the efficiency of 5-axis machining, it is necessary to minimize the cutter posture changes and create a continuous cutter path while avoiding interference. This study, by using an MC-space algorithm for interference avoidance and an MB-spline algorithm for continuous control, is intended to create a 5-axis machining cutter path with excellent surface quality and economic feasibility. finally, this study will verify the effectiveness of the suggested method through verification processing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.11
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• pp.894-901
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• 2017

In the existence of motion, azimuth phase error due to accuracy limitation of GPS/IMU and system delay is unavoidable and it is essential to apply autofocus to estimate and compensate the azimuth phase error. In this paper, autofocus algorithm using MWLS(Modified WLS) is proposed. It shows the robust performance compared with original WLS using new target selection/sorting metric and iterative azimuth phase estimation technique. SAR raw data obtained in a captive flight test is used to validate the performance of the proposed algorithm.

• Archives of design research
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• v.20 no.3 s.71
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• pp.247-256
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• 2007

Aging brings color-weakness to the eye due to yellowed eye sight. The 87% of information required for human behavioral decisions are visually perceived. Therefore, the color-weakness will affect behavior in many ways. Most of previous research regarding color planning for the aged focuses on discovering their preferred colors and reflecting the colors on facility color planning. But such research failed to identify the confused range of color cognitions due to the color weakness of the aged. The purpose of this study is to propose a design guide for fee-charging residential facilities for the elderly, reflecting upon color perception characteristics. An experimental simulation on aged vision using the UV filter and Y-2 filter, YA-3 filter alternating for general eyesight, 70 year-old and late 80 year-old was conducted. The results of this study are as follow : color perception is changed by crystalline lens aging process and yellowed eye sight. The recognition arrangement of colors was preferred to contrast harmony rather than similarity harmony and the dominant color is a warm color rather than a cool color.

• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.128-135
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• 2012

The individual toxicity of lead (Pb) and zinc (Zn) has been investigated by using the sea urchin (Hemicentrotus pulcherrimus) germ cell and pluteus-larvae. The gametotoxic and embryotoxic effects of Pb and Zn on H. pulcherrimus were each investigated at 31, 63, 125, 250, 500 ppb and 16, 31, 63, 125, 250 ppb, respectively. Spawning was induced by 0.5 M KCl solution and the fertilization and normal embryogenesis rates test were performed for 10 min and 64 h after fertilization, respectively. In exposure to Pb, the fertilization rate was not significantly changed compared with control but normal embryogenesis rate was significantly decreased with concentration dependent manner. Fertilization and normal embryogenesis rates showed a significant decreased with concentration dependent manner in exposed to Zn. The normal embryogenesis rates were significantly inhibited in exposed to Pb ($EC_{50}$=45.13 ppb, 95% Cl=40.12~50.05 ppb) and Zn ($EC_{50}$=19.82 ppb, 95% Cl=18.26~21.31 ppb). In exposure to Pb and Zn, the NOEC of normal embryogenesis rate was <31.25 and <15.63 ppb, respectively. The LOEC showed each 31.25 and 15.63 ppb in exposed to Pb and Zn. These results suggest that the early embryo development of H. pulcherrimus is highly sensitive to heavy metals such as Pb and Zn, H. pulcherrimus can be used as a test organism for risk assessment in marine ecosystems.