• 한국산학기술학회논문지
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• 제14권10호
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• pp.4753-4761
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• 2013

본 연구는 국악기 방사특성을 고려하여 다양한 마이크로폰의 설치 각도와 거리를 설정하여 국악기소리를 녹음한 후 녹음된 데이터를 주파수 스펙트럼과 반복청취를 통하여 음색특징을 분석, 가장 적합한 마이크로폰의 위치 및 녹음위치를 도출하였다. 본 연구의 실험은 대중음악에 사용되어지는 근접 마이크로폰 테크닉을 위한 실험이며 대중음악 녹음 스튜디오에서 이루어 졌다. 이 연구는 녹음 시 가장 적합한 마이크로폰의 위치 제시와 함께 다양한 위치에서 나타나는 음색의 차이를 설명하였다. 연구의 결과는 아름다운 우리 국악기 소리를 정확하게 표현하고 다양한 음색을 표현하기 위한 국악기 근접 마이크로폰 테크닉스로 사용될 수 있을 것이다.

• Restorative Dentistry and Endodontics
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• 제38권2호
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• pp.93-97
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• 2013

During root canal preparation procedures, the potential for instrument breakage is always present. When instrument breakage occurs, it leads to anxiety of the clinician and as well as a metallic obstruction of the canal which hinders further cleaning and shaping. Separated instruments must always be attempted for retrieval and if retrieval is not possible bypass should be tried. With the increased use of nickel-titanium (NiTi) instruments the incidence of separated instruments has increased. A considerable amount of research has been done to understand the various factors related to the fracture of NiTi instruments to minimize its occurrence. This paper presents a review of the literature regarding the fracture of NiTi instruments and also describes a case report showing the use of a modified 18-guage needle and cyanoacrylate glue to retrieve a separated NiTi instrument from the mesiolingual canal of a mandibular first molar.

• 대한정형도수물리치료학회지
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• 제15권1호
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• pp.1-8
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• 2009

Purpose: The purposes of this study were to establish the concurrent validity of the universal goniometer and electronic inclinometer for ankle joint of motion, and to determine the inter-tester and the intra-tester reliability of these two instruments. Methods: Subjects were instructed 25 healthy subjects. Ankle range of motion was measured on two separate occasions 2 or 3 days by two physical therapists. Ankle dorsiflexion and plantarflexion was by using an universal goniometer and an electronic inclinometer. Results: The Pearson product-moment correlation between the two instruments was 0.78~0.80. The ICCs for inter-tester reliability ranged from 0.63 to 0.73 for universal goniometer and ranged from 0.81 to 0.88 for electric inclinometer. The ICCs for intra-tester reliability showed a wide variation(ICC=0.61 to 0.86). Conclusion: These findings indicate that the two instruments are reliable instruments for measuring ankle joint range of motion. The results also indicate that the two instruments can be used interchangeably for measuring ankle motions.

• 천문학논총
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• 제27권3호
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• pp.61-69
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• 2012

The Ganui (簡儀, simplified armillary sphere) is a representative of astronomical instruments in Joseon Dynasty of Korea, as well as Yuan Dynasty and Ming Dynasty of China. In early 15th century, Joseon's scientists and engineers uniquely developed the Soganui (小簡儀, small simplified armillary sphere) and the Ilseongjeongsiui (日星定時儀, sun-and-star time determining instrument) from the structural characteristic of Ganui. These two astronomical instruments had a new design by the miniaturization and felt convinced a similar performance of Ganui in the harmony with Korean Astronomy and Astrology Cultures. Since mid-18th century after the enforcement of shixian-li (時憲曆), the Soganui and Ilseongjeongsiui handed over the Jeokdogyeongwiui (赤道經緯儀, equatorial armilla) by a change of the observational framework such as the time and angle measures. The Jeokdogyeongwiui made by Gwansanggam (觀象監, Bureau of Astronomy in Joseon Dynasty) adopted the new observational framework. We studied the structural characteristics and scientific values of these 3 astronomical instruments with theirs observation methods.

• Restorative Dentistry and Endodontics
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• 제43권2호
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• pp.15.1-15.7
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• 2018

Objectives: The present study aimed to evaluate the shaping ability of 2 thermally treated nickel-titanium reciprocating systems in simulated curved canals. Materials and Methods: Forty simulated canals were prepared to apical size 25 using Reciproc Blue R25 (VDW) and WaveOne Gold Primary (Dentsply Sirona) instruments. Standard pre- and post-preparation images were taken and superimposed. The removal of resin material was measured at 5 standard points: the canal orifice, halfway between the canal orifice and the beginning of the curve, the beginning of the curve, the apex of the curve, and the end-point of the simulated canal. The data were analysed using the independent sample t-test with a 5% significance threshold. Results: The canals in which Reciproc Blue R25 was used showed a significantly greater widening than those in which WaveOne Gold was used at 4 of the 5 measurement points (p < 0.05). The Reciproc Blue R25 instrument removed significantly more resin from the inner aspect of the curve at 2 of the 5 points and similar amounts at the remaining 3 points. At the 2 apical points, there was no significant difference between the Reciproc Blue R25 and WaveOne Gold Primary instruments. Conclusion: Both instruments respected the original canal anatomy; however, WaveOne Gold resulted in a more conservative shape with less transportation.

• Restorative Dentistry and Endodontics
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• 제7권1호
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• pp.17-24
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• 1981

The purpose of this study is to compare the shape of the apical regions of root canals after instrumentation by various enlarging instruments. 120 extracted, single-rooted human teeth were seperated into 4 experimental groups. Each group provided 30 teeth for experimental use. Group 1 root canals instrumented by the hand-operated Reamer. Group 2 root canals instrumented by the hand-operated H-file. Group 3 root canals instrumented by the hand-operated K-file. Group 4 root canals instrumented by the automated Giromatic file. The results were as follows: 1. The degree of the roundness of the apical regions of root canal walls: 1) Hand-operated instruments were superior to the automated Giromatic file. 2) The Reamer was the most effective instrument among hand-operated instruments 3) There was little difference between the H-file and the K-file. 2. The degree of the smoothness of the apical regions of root canal walls: 1) Root canal walls instrumented by the hand-operated Reamer, H-file and, K-file were generally smooth, and there was little difference among them. 2) Root canal walls instrumented by the automated Giromatic file showed many irregular canal walls. 3. The existance of organic debris in the apical regions of root canals: All organic debris is not removed from root canals, and there was little difference between hand-operated instruments and the automated Giromatic instrument in removing organic debris.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.597-598
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• 2003

I. Objectives Endodontic success depends on thoroughly cleaned and completely obturated root canal system. Effective cleaning and obturation will be achieved by well shaped canal. Numerous methodologies evaluating the efficacy and safety of canal preparation has been developed and the use of micro-computed tomography(MCT) in endodontic research is one of the latest innovations. This scientific tools could overcome the inherent limitations of other methodologies, and possesses the ability to visualize morphological characteristics in a detailed and accurate manner without destruction of the tooth and offers reproducible data in all three dimensions. The purpose of this study was to determine the optimal master apical file size with less transportation and more efficiency in removing the infected dentin. For this purpose we evaluated the transportation of canal center and change of untouched area after preparation sequentially from ＃25 file through ＃40 file with 3 different instruments：Stainless steel(SS) K-type hand instruments(MANI, Japan), ProFile.04 instruments (Dentply Tulsa Dental, USA) and Lightspeed instruments(Lightspeed Technology, San Antonio, USA) using micro-computed tomography.(omitted)

• 한국항공우주학회지
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• 제49권4호
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• pp.343-354
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• 2021

공공민간협력(Public-Private Partnerships)은 공공부문과 민간부문의 협력적 관계를 통해 공동의 목표를 달성하는 운영방식이다. 최근 우주분야에서 공공민간협력이 중요해짐에도 불구하고 민간부문과 공공부문 간 협력적 네트워크를 활성화 시키는 정책수단에 관한 연구는 부족했다. 이 연구는 선진국에서 사용 중인 16가지 정책수단을 4가지(구매계약, 재정지원, 연구개발지원, 자원지원)로 유형화하였다. 그리고 미국, 유럽, 일본 등 5가지 공공민간협력 운영사례 연구를 통해 우주산업 경쟁력 강화에 도움이 되는 정책적 시사점을 발굴하였다.

• 대한치과의료관리학회지
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• 제9권1호
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• pp.25-31
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• 2021

The aim of this study was to investigate the level of dental infection control experienced by dental hygiene students in clinical practice institutions to identify problems and improve infection control in dental institutions. This study conducted online surveys targeting 269 dental hygiene students from universities that conducted clinical practice to determine the students' level of awareness regarding dental infection control in dental institutions and the reality of infection control in dental institutions. The results showed that dental hygiene students recognized the need for infection control and education about infection control at a high level. However, only 47% of the students were accurately informed about COVID-19. Basic instruments, periodontal instruments, and implant surgical instruments were sterilized after use for each patient, mostly by the institution, but 3-way syringe tips, preservation instruments and prosthetic instruments were more frequently reused without sterilization immediately after use. For dental infection control to be practiced at dental institutions, it is necessary to establish a systematic and safe infection control system, including infection control education, designation of infection managers, and provision of infection control guidelines.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.458-467
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• 2000

The standard of performance-based seismic design accepted by Ministry of Construction and Transport requires to install and manage earthquake instruments for the facilities of seismic category I and to acquire earthquake response data of these facilities at earthquake events. So detailed standard and guideline for installation and management of earthquake instruments for each facilities according to the seismic design standard are getting ready. This paper presents the part of installation locations of sensors in that detaile standard and guideline.