• Restorative Dentistry and Endodontics
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• v.26 no.4
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• pp.326-331
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• 2001

목적 - 최근 복합레진의 미세변연누출을 줄이기 위한 새로운 광중합 조사방법이 연구되고 있다. 또한 구치용 복합레진이 개발되면서 그 제조회사에서는 5mm 깊이까지 광중합이 가능하다고 소개하고 있다. 본 연구에서는 논리적 가설에 근거한 몇가지 광중합 조사방법이 구치부 class II 와동의 복합레진 충전시 미세변연누출에 어떠한 영향을 미치는지를 관찰하였다. 재료 및 방법 - 100개의 우식증이 없는 사람의 상하악 대구치를 사용했다. 각 치아에 교합-치은방향으로 4mm, 협설 4mm, 깊이 2mm의 class II 와동을 형성하여 인접치와 함께 베이스플레이트 왁스에 매몰하고 구치용 복합레진인 Surefil을 제조 회사의 지시대로 충전하였다. 이때 5가지의 광조사방법을 이용하여 5개의 군으로 나누어 중합하였다(Table 1). 수복된 치아들을 5$^{\circ}C$와 55$^{\circ}C$의 수조에서 번갈아 1분씩 총 500회의 온도변화를 주어 thermocycling을 실시한 후 근첨을 폐쇄하고 수복와동의 치은경계를 제외한 전 표면에 nail varnish를 2회 도포하였다. 2%의 methylene blue용액에 24시간 침적시키고 흐르는 물에 세척한 후 시편을 투명한 에폭시 레진에 매몰하였다. 매몰된 시편을 치아 장축에 평행하게 절단 연마하였다. 입체 현미경으로 미세변연누출을 관찰하고 Kruskal-Wallis One Way ANOVA 와 Dunn's Method로 통계처리 하였다. 결과 - 1. 미세누출은 1군, 4군과 5군, 2군 3군 순으로 증가였다. 이때 1군, 4군과 5군은 통계적 유의성이 없었다(P>0.05). 2. 2군의 경우 1군, 4군, 5군에 비교하여 유의성 있게 미세누출이 많았으며(P<0.05) 3군에 비하여 유의성 있게 적게 나타났다(P<0.05). 3. 3군의 경우 다른 방법들에 비교하여 통계적으로 유의성 있게 미세누출이 많았다(P<0.05).

• Journal of Biomedical Engineering Research
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• v.44 no.1
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• pp.1-10
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• 2023

With the announcement of MEDICAL DEVICE REGULATION 2017/745 (MDR) on April 5 2017, medical device manufacturers shall apply ISO 14971:2019 (3^rd) revised in December 2019. However, there is not much related information and guidance available to medical device manufacturers, especially single use medical device. Risk management process basically follow 5 steps which are Risk Analysis, Risk Evaluation, Risk Control, Evaluation of overall residual risk and post-production activities. The purpose of this study is to provide a guidance of from risk analysis with Failure Mode and Effects Analysis (FMEA) table to overall residual risk evaluation for the single use medical device and to reflect it in a Periodic Safety Update Reports (PSUR) to satisfy with MDR requirements with single use medical device which are widely used and manufactured FDA class 2 or CE class IIb as examples. For this study, single use medical device manufacturer can adopt ISO 14971:2019 in accordance with MDR requirements and it can be extended to the PSUR. But there are still limitations to adopt to the all-single use medical device especially high class, private device and implantable device. So, Competent Authority (CA) shall publish more guidance for the single use medical device.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.5
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• pp.127-135
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• 2010

In motion adaptive temporal noise reduction filtering used for reducing video noises, the strength of motion adaptive temporal filtering should be carefully controlled according to temporal movement. This paper presents a motion adaptive temporal filtering scheme based on least-square training. Each pixel is classified to a specific class code according to temporal movement, and then, an iterative least-square training method is applied for each class code to find optimal filtering coefficients. The iterative least-square training is an off-line procedure, and the trained filter coefficients are stored in a lookup table (LUT). In actual noise reduction filtering operation, after each pixel is classified by temporal movement, simple filtering operation is applied with the filter coefficients stored in the LUT according to the class code. Experiment results show that the proposed method efficiently reduces video noises without introducing blurring.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.06a
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• pp.67-92
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• 1997

Tap water should be shown the complexity of measures neccessary to secure water quality, especially with respect to drinking and bathing. Designated reservoirs Paldang and Daechung as the Special Environment Protection Areas to regulate new pollution sources and to facilitate construction of wastewater treatment facilities. In this country, 91% of total drinking water resource, consist of 66% stream water, 25% dam water, 7% dune flitrate, 1% each of spring and ground water, are from the surface water. The total volume of annual mean water resources due to precipitation. Over 8% of the total resources are class III as shown in the table., eapecially the water quality of downstream of Nakdong and Yeongsan river are getting worse due to continued economic and social development.

• International journal of advanced smart convergence
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• v.8 no.2
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• pp.183-190
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• 2019

In the era of the Fourth Industrial Revolution, digital transformation, which means changes in all industrial structures, politics, economics and society as well as IT technology, is an important issue. It is difficult to know which research topic is being studied because digital transformation is being studied in various fields. Convergence research is possible because a research topic is studied in various fields such as computer science area and Decision science area. However, it is difficult to know the specific research status of the research topic. In this study, eight research topics were derived using the topic modeling technique of text mining for abstract of academic literature and the trend of each topic was analyzed. We also proposed to create a Topic-Word Proportions Table in the LDA based Topic modeling process to predict the topic of new literature. The results of this study are expected to contribute to advanced convergence research on topic of digital transformation. It is expected that the literature related to each research topic will be grasped and contribute to the design of a new convergence research.

• The Plant Pathology Journal
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• v.34 no.2
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• pp.85-92
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• 2018

Enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR), widely used for the detection of plant viruses, are not easily performed, resulting in a demand for an innovative and more efficient diagnostic method. This paper summarizes the characteristics and research trends of biosensors focusing on the physicochemical properties of both interface elements and bioconjugates. In particular, the topological and photophysical properties of quantum dots (QDs) are discussed, along with QD-based biosensors and their practical applications. The QD-based Fluorescence Resonance Energy Transfer (FRET) genosensor, most widely used in the biomolecule detection fields, and QD-based nanosensor for Rev-RRE interaction assay are presented as examples. In recent years, QD-based biosensors have emerged as a new class of sensor and are expected to open opportunities in plant virus detection, but as yet there have been very few practical applications (Table 3). In this article, the details of those cases and their significance for the future of plant virus detection will be discussed.

• Journal of Species Research
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• v.12 no.1
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• pp.1-26
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• 2023

A faunal study on Amphipods belonging to the class Malacostraca was conducted 26-29 August 2021 at 12 sites in Chujado Island, Korea. This study found that 68 amphipod species in 39 genera, 19 families were living on Chujado Island. Among these 19 families, the family Caprellidae (20 species) showed the highest abundance. Ampithoidae (7 species) and Dexaminidae (6 species) were subdominant families. The species Stenothoe valida Dana, 1852 (found at 10 of 12 sites) was the most frequent and widespread species. Caprella scaura Templeton, 1836 was identified at 9 of 12 sites and had the highest frequency of appearance among 20 species of Caprellidae. Among the 68 species, Ampithoe waialua J.L. Barnard, 1970 and Melita nagatai Yamato, 1987 are newly recorded species in Korean fauna. These newly recorded species are fully illustrated and compared with related species. We provide an amphipod fauna in Chujado Island with a list, figures, and a table.

• ETRI Journal
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• v.28 no.6
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• pp.745-760
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• 2006

In this paper, we particularly deal with no $F_p$-rational two-torsion elliptic curves, where $F_p$ is the prime field of the characteristic p. First we introduce a shift product-based polynomial transform. Then, we show that the parities of (#E - 1)/2 and (#E' - 1)/2 are reciprocal to each other, where #E and #E' are the orders of the two candidate curves obtained at the last step of complex multiplication (CM)-based algorithm. Based on this property, we propose a method to check the parity by using the shift product-based polynomial transform. For a 160 bits prime number as the characteristic, the proposed method carries out the parity check 25 or more times faster than the conventional checking method when 4 divides the characteristic minus 1. Finally, this paper shows that the proposed method can make CM-based algorithm that looks up a table of precomputed class polynomials more than 10 percent faster.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.225-231
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• 2005

This study aims to suggest an evaluation methodology of green-tourism potential for village level with amenity resources in rural areas. The amenity resources system was classified into three sub-classes(social, industrial, and natural/cultural/historical resources) and a relationship diagram between three classes and tourists' behavior was also defined. The methodology considers human resources in the village including the three sub-class amenity resources. The table and diagram were applied to make renewal plan for rural villages of the study area, Nami-myun, Keumsan-gun, Chungnam province, so that the development scheme for the villages was suggested reasonably by the new findings of this study.

• Research in Mathematical Education
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• v.12 no.3
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• pp.193-200
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• 2008

In this study, an innovative computer support has been suggested to improve differential perception of the students. Research has been conducted on a calculus class which has 35 students. A semi-structured interview has been reported in the study. By this interview, it was tried to make differential concept more understandable by using Micro Soft Excel component of the well-known MS Office software. By this aim, students have been asked to integrate a simple function by using MS Excel. At the end of the study, it was observed that differential concept made more sense in students' minds than previous.