• Restorative Dentistry and Endodontics
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• v.35 no.6
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• pp.429-435
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• 2010

Objectives: The aim of this study was to investigate average working lengths of Korean posterior teeth and evaluate validity of endodontic file length. Materials and Methods: The endodontic working length of the posterior teeth of 670 Korean patients were measured than each mean value and standard deviation were investigated than the frequency deviation and standard deviation per each length were calculated. Results: Among the canals of premolar, 66.5% of canal length was marked under 20 mm by endodontic working length and 95.4% could be measured under 22 mm and Among the canals of molars, 95.5% of canal length was marked under 20 mm endodontic working length. Conclusions: With the result of measurement of endodontic working length of premolars of Korean, it suggested that 23 mm endodontic file is more proper than the 21 mm and 25 mm file on the market.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.808-814
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• 2021

The International Maritime Organization (IMO) explicitly stipulates the required performance of satellite based radio-navigation systems available for navigational purposes. Until 2019, the IMO had only recognized systems that could be serviced globally for satellite based radio-navigation. However, India's regional navigation satellite system has been approved recently, and other regional navigation satellite systems have also been made available for maritime navigation. Thus far, the IMO has approved the use of a total of five satellite navigation systems, such as the GPS, GLONASS, Galileo, BeiDou, and NavIC. In Korea, in addition to the four satellite based radio-navigation systems that are used excluding NavIC, Japan's regional navigation satellite system that has not yet been approved can be received. Japan has requested the IMO to recognize the QZSS as a WWRNS to formalize its use for ocean navigations. Given that the service coverage of the QZSS is not limited to Japanese territorial waters and also includes Korean waters, the suitability analysis of the QZSS for domestic navigation is important for maritime safety. This study aims to analyze the suitability of using the QZSS for domestic navigation. Accordingly, this work explores the status and plans of the QZSS as well as the performance required by the IMO for recognition as a WWRNS. The methods and environmental conditions examined in this work are described, and the analyzed results are presented in terms of positioning accuracy and availability.

• The Journal of the Korea Contents Association
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• v.19 no.9
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• pp.271-279
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• 2019

The life expectancy of people has been steadily extended due to the improvement of living standards and the development of medical technology. Besides, the low birth rate and long life expectancy decrease the youth population while the elderly population is steadily increasing. Many elderly people have enough time and financial allowance, and the interest in health care is increased all over society. There are also increasing numbers of elderly people who exercise lightly in the playgrounds and parks such as running and walking. Outdoor fitness equipment that can be easily seen in neighbourhood parks, public spaces, etc. can be good health promotion tools that can be easily accessed in the daily life of the elderly. Outdoor fitness equipment Description Signs require a design that takes into account the declining vision of older users. Proper design is also important for the prevention of safety accidents in use. The purpose of this study is to find out the perception of the elderly about outdoor fitness exercise equipment sign system and to find the problem of recognition. To do this, we conduct user observation and interview surveys for the elderly. As a result, the emphasis of the caveat or problems with the size of the writing were pointed out, and it was necessary to explain the picture rather than the text. Also, there was a high demand for refraining from using foreign words, using universal words and including motor effects in signs. Based on the results of the user observation and interviews, we propose guidelines for the use of outdoor exercise equipment.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.1
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• pp.27-36
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• 2019

Purpose: The aims of this study were to evaluate the dentist's awareness and the actual status of infection control of noncritical dental instruments. Materials and Methods: 40 dental clinics in Daejeon, South Chungcheong, North Chungcheong and North Jeolla provinces were surveyed. The questionnaire was delivered to the dentists belonging to those clinics, and the awareness and the practice of infection control were examined. The microbial contamination on the surface of five noncritical instruments (impression gun, light curing unit, 3-way syringe, shade guide, and dental floss dispenser) used by them was measured with an ATP luminometer. Correlation analysis between the awareness and the actual state of infection control was conducted. Results: Awareness and frequency of infection control was highest in the 3-way syringe. Surface disinfection using disinfectant was most frequent in all instruments. 3-way syringes and shade guides were less contaminated than impression guns, light curing units, and dental floss dispensers. Conclusion: 3-way syringes had a significant correlation between user awareness of infection control and surface contamination, and the higher awareness, the lower the contamination measurement was shown.

• The Journal of Korean Society for Radiation Therapy
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• v.35
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• pp.33-39
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• 2023

Purpose: The purpose of this study is to find out the dose variation according to thickness of the air gap between the patient's body surface and immobilization device in the treatment plan. Materials and Methods : Four conditions were created by adjusting the air gap thickness using 5 mm bolus, ranging from 0 mm to 3 mm bolus. Immobilization was placed on top in each case. And computed tomography was used to acquire images. The treatment plan that 430 cGy (Relative Biological Effectiveness,RBE) is irradiated 6 times and the dose of 2580 cGy (RBE) is delivered to 95% of Clinical Target Volume (CTV). The dose on CTV was evaluated by Full Width Half Maximum (FWHM) of the lateral dose profile and skin dose was evaluated by Dose Volume Histogram (DVH). Result: Results showed that the FWHM values of the lateral dose profile of CTV were 4.89, 4.86, 5.10, and 5.10 cm. The differences in average values at the on the four conditions were 3.25±1.7 cGy (RBE) among D_95% and 1193.5±10.2 cGy (RBE) among D_95% respectively. The average skin volume at 1% of the prescription dose was 83.22±4.8%, with no significant differences in both CTV and skin. Conclusion: When creating a solid-type immobilization device for carbon particle therapy, a slight air gap is recommended to ensure that it does not extend beyond the dose application range of the CTV.

• Review of KIISC
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• v.12 no.4
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• pp.16-22
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• 2002

ASTAP Forum은 1998년 2월 아태지역의 표준화 활동 및 ITU, ISO등의 국제 표준화 기구에 회원국의 공동 입장을 반영하기 위해 설립된 APT 산하 표준화 기구이다. 여기에는 PKI 연동, VPN, 암호 알고리즘, ESM 로그, AP-CERT, 멀티캐스트, 정보보증등과 같은 정보보호 표준화 업무를 담당하는 정보보호 전문가 그룹이 있다. 본 기고문에서는 ASTAP Forum의 현황을 설명하고, 정보보호 전문가 그룹에서 현재가지 많은 논의가 이루어지고 있는 정보보호 항목에 대한 설명과 함께 여기에는 어떠한 이슈들이 있는지 알아보고자 한다.

• Information and Communications Magazine
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• v.32 no.1
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• pp.53-61
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• 2014

2015년도에 한국정보통신기술협회(TTA)는 표준의 보급 확산 활성화, 사실 표준화 기구에 대한 대응 활동강화, 국민 편익형 표준화의 본격추진, 중소기업에 대한 표준 지원활동 강화를 주요 목표로 삼고 이를 추진하기 위한 표준화 전략을 수립하였다. 이러한 목표를 달성하기 위한 세부 전략으로는 표준의 경제적 효과 분석, 국민 편익/생활 밀착형 표준화 본격추진, 기 제정된 TTA 표준의 Use Case 세부 조사 분석, 사실표준화기구에 대한 대응체계구축, 중점 표준화 분야와 적합성/인증연계, 표준보급활동 강화를 위한 맞춤형 표준설명회 개최 및 표준해설서 개발, 중소기업을 지원하기 위한ICT 표준화 사이버 지원센터 운영 등의 전략을 수립하였다.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.13
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• pp.17-26
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• 2004

국가 차원에서 과학기술정보활동을 담당하고 있는 일본과학기술진흥기구와 프랑스과학기술정보연구원은 정부로부터 예산지원을 받는 공공기관이다. 본 글에서는 일본과학기술진흥기구와 프랑스과학기술정보연구원의 과학기술정보활동, 조직 및 사업내용에 대해 개략적으로 살펴보고자 한다. 그리고 이를 각 기관의 정보유통체계를 정보자원의 수집, 콘텐트 개발, 정보서비스 측면에서 살펴보고 한국 과학기술정보활동의 핵심적 역할을 담당하고 있는 KISTI에 시사점을 제시하고자 한다.

• Journal of Korean Electronics
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• v.19 no.12
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• pp.44-46
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• 1999

중국이 드디어 지난 86년 7월 GATT 재가입신청 이후 지난 11월 15일 미국과의 가입협상이 타결됨에 따라 13년 만에 세계무역기구(WTO)의 사실상 정식회원국(내년 3월 예상)이 되었다. 이는 세계경제에 새로운 획을 긋는 일대 사건이며 우리 경제 전반에도 적지 않은 영향을 미치게 될 것으로 보인다. 이에 본지에서는 중국의 WTO가입이 우리 경제 특히, 전자산업에 미치는 영향이 클 것으로 판단돼 그간 각종 언론매체에서 다룬 분석내용들을 중심으로 편집 재구성해 본다.

• Information and Communications Magazine
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• v.33 no.9
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• pp.59-63
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• 2016

W3C는 웹에 대한 국제표준을 개발하는 표준화 기구로 HTML5 표준을 포함하여 CSS, XML, OWL 등 웹 생태계에 필요한 핵심적인 표준을 개발해 왔으며, 최근에는 웹 페이먼트, 사물웹, 오토모티브 웹에 대한 표준을 개발하는 하고 있다. 본 고에서는 표준화 기구인 W3C에 대한 간단한 소개와 함께 최근에 주요하게 개발되고 있는 표준을 중심으로 W3C 표준화 동향에 대해서 알아본다.