• Restorative Dentistry and Endodontics
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• 제28권2호
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• pp.146-155
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• 2003

여러 가지 장점으로 인해 Ni-Ti 전동 파일을 근관성형에 사용하는 빈도가 점차 증가되는 추세이지만, 초심자를 대상으로 한 연구는 부족한 실정이다. 이에 본 연구에서는 초심자에서 Ni-Ti 전동 파일을 사용할 때 근관 형성의 효용성을 평가하고, 어떤 방법이 초심자에게 적절한지를 알아보고자 하였다. 근관형태가 재현된 레진 블록을 이용하여 12명의 초심자와 4명의 숙련자가 근관 형성을 시행하였다. 각 술자는 ProFile, ProTaper, Hybrid (ProFile＋ProTaper)를 이용하여 각각의 레진 블록을 세 개씩 근관형성하고, 각 파일 별의 근관 형성 시간을 기록하였다. 근관 형성 전과 후의 digital 이미지를 중첩하여 치근단으로부터 1, 2, 3, 4, 5, 6, 7mm level에서 근관단면의 총길이 변화량, 만곡 외측의 길이 변화량, 만곡 내측의 길이 변화량, 중심이동량, 중심이동율과 치근단에서의 apical transportation을 구하고, 초심자와 숙련자 사이의 차이를 비교 평가하였다. 실험결과 ProFile군의 1, 3, 5, 6, 7mm level과 ProTaper군의 6mm level, Hybrid군의 3mm level에서 초심자의 근관단면의 총길이 변화량이 숙련자보다 많았다. 모든 군에서 치근단으로부터 4, 5, 6, 7mm level에서는 근관 중심이 만곡내측으로 이동하였고, 1 2, 3mm level 에서는 만곡외측으로 이동하였으나, 숙련자가 시행한 Hybrid군의 3mm level과 비숙련자가 시행한 ProTaper 군의 3mm level에서는 만곡내측으로 이동하였다. 모든 군의 3mm level과 ProFile 군의 5mm level에서 초심자의 중심이동율이 숙련자에 비해 컸으며, 초심자가 ProTaper를 사용시 더 큰 apical trans portation을 보였고, 모든 군에서 초심자가 근관형성시 더 많은 시간이 걸렸다. ProFile과 ProTaper를 이용한 Hybrid technique이 초심자에게 추천되며, 초심자들도 충분히 교육받는다면 만곡된 근관의 근관형성에 있어서 Ni-Ti rotary file의 이용이 가능하리라고 사료된다.

• 한국컴퓨터정보학회논문지
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• 제28권1호
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• pp.55-63
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• 2023

본 논문에서는 재난 위기경보 발령을 하기 위해 상황판단 기준을 자동분석하는 재난위기경보관리시스템의 기능 및 서비스와 국가재난관리정보시스템(NDMS) 체계에서 운영하기 위한 방안을 제안한다. 재난 발생시 위험수준에 따라 위기경보(관심-주의-경계-심각)를 발령하고 있다. 위기경보 수준을 자동분석 판단하기 위해 첫째, 데이터 수집, 위기경보 수준 분석, 위기경보 수준 판단, 공간규모별(시도, 시군구) 위기경보 등급을 표출하는 재난위기경보관리시스템을 구현하였다. 위기경보 수준 판단은 지능형 위기경보 수준(지역민감도, 위험수준, 위기경보 등급 판단)과 위기관리 매뉴얼의 위기경보 기준(시도 단위 기준 표준 설정)을 적용하여 두 가지 방식으로 분석하여 표출한다. 둘째, 국가재난정보관리시스템내에서 운영할 수 있도록 재난안전데이터 공유 플랫폼의 데이터 연동과 위기경보 데이터를 공동활용하기 위해 표준 메타데이터(구성항목 정의), 상황정보 연계(대상 정의), 데이터 제공을 위한 openAPI 표준을 제시한다.

• International Journal of Advanced Culture Technology
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• 제11권3호
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• pp.211-224
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• 2023

This study surveyed 2nd graders of B high school and 1st graders of A university in Gyeongnam on factors such as behavior control and interaction in non-face-to-face classes, easy or difficult concepts presented in chemistry I and general chemistry textbooks. Based on the results of the survey, the effect of changes in the difficulty level of concepts presented in chemistry I and general chemistry and changes in class types (face-to-face and non-face-to-face) on students' academic achievement by level was compared and analyzed. In the face-to-face class, the average score between the first and second semesters was similar according to the change in the difficulty of the concepts presented in chemistry I and general chemistry. In the non-face-to-face class, the average score of chemistry I in the second semester was quite low, and the average score of general chemistry was rather high. In non-face-to-face classes, the average score of chemistry I in the second semester of low-level students was significantly lowered due to changes in the difficulty of the concept and changes in class types on academic achievement by level. In the case of 10% of students at the lower level, the academic achievement of chemistry I decreased in both the second semester regardless of the changes in the difficulty level of concepts and the changes in class types.

• 한국수정란이식학회지
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• 제28권3호
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• pp.237-241
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• 2013

It is generally accepted that chronic stress impairs female reproduction. It negatively affects ovarian function and the number of ovulated oocytes. Chronic stress lowers the number of retrieved oocytes. Ovarian follicular development is regulated by both pituitary-derived gonadotropins and intraovarian regulatory factors. The main corticosteroids are cortisol, cortisone, 11-deoxycortisol and corticosterone, cortisol being one of the most commonly used welfare and stress physiological indicator. In this study, we investigated the effect of cortisol level on progesterone patterns and ovulation in the dog. Cortisol and progesterone level of serum were analyzed by radioimmunoassay. The day of ovulation was considered as the day when serum progesterone concentration was 6.0~8.0 ng/ml. In vivo dog oocytes were collected by flushing oviducts of mixed-breed bitches at three days after ovulation. We classified dogs as having group 1 (cortisol level, 0 ${\leq}$ or < $2{\mu}g/dl$), group 2 (corisol level, 2 ${\leq}$ or < $4{\mu}g/dl$), group 3 (cortisol level, 4 ${\leq}$ or < $6{\mu}g/dl$) and group 4 (cortisol level, $6{\mu}g/dl$ ${\leq}$). The patterns of progesterone were not different in four cortisol groups. The average numbers of retrieved oocytes was not different in four cortisol groups. These results suggest that different cortisol levels on estrus dogs do not affect ovulation, number of ovulated oocytes and progesterone changes.

• 대한가정학회지
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• 제44권11호
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• pp.133-148
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• 2006

This study takes an effort to suggest solutions for medical service consumers' sovereignty. Specifically, consumer evaluation, information seeking level, and affecting factors on information seeking level were explored in terms of medical service. In present study, medical information included medical institution and doctors, prescription, diseases, medical treatment and medical expense. Medical service consumers' information seeking is identified as consumers' own efforts to acquire medical information through various sources. The analysis results suggested that consumers' information seeking level is even lower, while their evaluation level is somewhat low. Moreover, the result for information seeking level by consumer characteristics implied that people who have high education, high economic status, medical knowledge, and high attitudes for consumer right are active information seekers. Finally, consumer attitudes for right appeared most influential factor on information seeking level, implying direction for medical service consumer education.

• Journal of information and communication convergence engineering
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• 제6권4호
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• pp.430-433
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• 2008

A merged altimeter data products are used to estimate sea level variation in the East Sea between 1993 and 2006. The altimeter data show a high correlation coefficient (0.85) after applying gaussian low pass filter for 180days at Ulleung island. The both of Mukho coast and Ulleung island are minimal sea level in March to May and maximal in September to November. Sea level of Mukho coast is higher than that of Ulleung island during March to May, while Mukho coast is lower during September to November because the North Korea Cold Current flows along the coast line of Mukho. Generally sea level variation at Mukho coast and Ulleung island associated with seasonal variations.

• Journal of Information Processing Systems
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• 제5권1호
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• pp.1-4
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• 2009

Level set methods are the numerical techniques for tracking interfaces and shapes. They have been successfully used in image segmentation. A new variational level set evolving algorithm without re-initialization is presented in this paper. It consists of an internal energy term that penalizes deviations of the level set function from a signed distance function, and an external energy term that drives the motion of the zero level set toward the desired image feature. This algorithm can be easily implemented using a simple finite difference scheme. Meanwhile, not only can the initial contour can be shown anywhere in the image, but the interior contours can also be automatically detected.

• 대한가정학회지
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• 제43권5호
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• pp.57-79
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• 2005

The purpose of this study was to investigate the needs assessment and satisfaction level of family support services for preschoolers with disabilities. The subjects were 146 mothers and 138 teachers of 3- to 6-year- old preschool children with disabilities in integrated kindergartens in Daegu, Seoul, and Kyungnam. The major findings of this study were as follows. First, mothers needed information and financial support most. The level of the mother's needs was related to the type and degree of disabilities, child's sex, child's age, mother's educational level, and father's occupation. Second, the satisfaction level of mothers in the integrated kindergarten education programs was generally low. Third, mothers needed parental training of child's problem behavior, mother-child interactions program, and parental education of developing child's creativity.

• Child Health Nursing Research
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• 제27권4호
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• pp.385-394
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• 2021

Purpose: This study investigated the relationships between mothers' knowledge and practice level of cough etiquette and their children's practice level of cough etiquette as perceived by their mothers. Methods: This study was a descriptive correlational study. The data were collected from 160 mothers with preschoolers attending daycare centers and kindergartens in Gwangju, South Korea using self-reported questionnaires. Results: The correct answer rate for cough etiquette knowledge in mothers was 86.0%, mothers' average practice score was 33.65±4.14, and their children's average practice score was 28.39±4.85 out of 48. The correlation between mothers' cough etiquette knowledge and practice level was not statistically significant. However, mothers' cough etiquette practice was positively correlated with children's cough etiquette level as perceived by mothers (r=.35, p<.001). Conclusion: The development of a systematic cough etiquette education program and measurements for both mothers and children according to their developmental stages is important to effectively prevent respiratory infections.

• 전력전자학회논문지
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• 제23권6호
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• pp.415-423
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• 2018

This study uses a level selection algorithm with fixed sampling frequency for modular multilevel converter (MMC) systems. Theoretically, the proposed method increases the level infinitely while the sampling time remains the same. The proposed method called cluster stream buffer (CSB) consists of several clusters, wherein each cluster is composed of 32 submodules that depend on the level of the submodules in the MMC system. To increase the level of the MMC system, additional clusters are used, and the sampling time between clusters is determined from the sampling time between levels needed for utilizing the entire level from the MMC system. This method is crucial in the control of MMC-type HVDC systems because it improves scalability and precision.