• Title/Summary/Keyword: 폐쇄자

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Aortic Valvuloplasty Using Leaflet Extension Technique (판막첨 연장술을 이용한 대동맥판막 성형술의 중기성적 평가)

  • Ahn, Hyuk;Kim, Hyun-jo
    • Journal of Chest Surgery
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    • v.30 no.7
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    • pp.656-662
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    • 1997
  • Aortic valvuloplasty has recently gained attention as an attractive alternative procedure for aortic valvular disease. Between March 1995 to August 1996, 14 patients with pure aortic regurgitation(AR) underwent aortic alvuloplasty using leaflet extension with glutaraldehydepreserved autologous pericardium. There were 11 males and 3 females, and the mean age was 34.8 $\pm$ 15.3 years. Preoperative echocardiography and cardiac catheterization revealed that the degree of AR was mean 3.4$\pm$0.65, and more than moderate degree of mitral regurgitation(MR) were detected in 4 patients. In 12 patients, 3 leaflets were extended and in another 2 patients only one deformed leaflet was extended. Concomitant mitral valvuloplasty (MVP) was performed in 4 patients. The competency of the aortic valve after completion of repair was evaluated by the transesophageal echocardiography in operating theater, and there was no aortic and mitral stenosis or regurgitation. In an early postoperative echocardiography, trivial AR was detected in 3 patients and mild MR in 1 patient. The end-systolic and end-diastolic dimensions of the left ventricle were decreased significantly(p<0.05) as compared with those of preoperative values. T ere was no mortality and no significant postoperative complication encountered. Late complication developed in 2 patients during the follow-up period(mean 7.9$\pm$ 5.9 months). One patient underwent AVR on postoperative 7th month due to endocarditis, and the another patient with Behcet's disease underwent Ross operation at postoperative 4th month. In conclusion, AVP of leaflet extension technique offers an excellent early clinical result and represents a good alterna!ivy surgical treatment for the pure AR especially in young age group, although long-term follow-up is necessary to determine the durability of glutaraldehyde-preserved autologous pericardium as a valve leaflet.

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Development of Mobile WebApp Enclosed SNS Based Student Council Management Program (모바일 웹앱 폐쇄형 SNS 기반 학생회 관리 프로그램 개발)

  • Lee, Tae Woon;Kim, SungHee;Lee, HwMin
    • Proceedings of the Korea Information Processing Society Conference
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    • 2013.11a
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    • pp.433-436
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    • 2013
  • 폐쇄형 SNS란 카페 블로그 등 온라인 상의 커뮤니티 서비스를 모바일로 옮겨 놓은 것이다. 이메일 주소나 전화번호로 연결된 모든 지인을 일괄적으로 친구로 등록하는 개방형 SNS와 달리, 친밀도에 따라 지인을 따로 관리할 수 있다. 개방형 SNS에 비해 가입자 폭은 넓지 않지만 이용자 충성도가 높다는 게 큰 장점으로 꼽힌다. 이에 본 논문에서는 폐쇄형 SNS를 통하여 학교에서 리더를 맡고있는 회장, 학회장 등에게 효과적으로 학생회를 운영 할 수 있는 어플리 케이션을 제공한다. 이를 통해 사용자들은 효과적인 학과 운영과 질높은 행사, 투명한 학회비 관리 등을 제공받을 수 있다.

Analysis of Covert Channel Attack Techniques Based on Acoustic Signals (음향신호 기반 Covert Channel 공격 기술 분석)

  • Wooyoung Son;Soonhong Kwon;Jong-Hyouk Lee
    • Proceedings of the Korea Information Processing Society Conference
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    • 2024.05a
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    • pp.395-396
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    • 2024
  • 최근 국가 핵심 기반시설을 중단시키거나 파괴시킴으로서 사회적 혼란 및 국가 경제적 손실을 일으키는 공격 사례가 증가되고 있는 실정이다. 이와 같은 사이버 공격에 대응하기 위해 각 국가는 인터넷이나 다른 네트워크와 물리적 또는 논리적으로 분리되어 있는 폐쇄망 환경을 기반으로 기반시설을 구성함으로서 높은 수준의 보안성과 안정성을 유지하고자 한다. 하지만, 악의적인 공격자들은 Covert Channel을 통해 폐쇄망 환경 내 민감한 데이터 및 기밀 데이터를 탈취하고 있는 실정이다. 이에 본 논문에서는 음향신호 기반 Covert Channel 공격 기술에 대해 분석함으로써 안전한 폐쇄망 환경 구축의 필요성을 보이고자 한다.

Learning acoustic cue weights for Korean stops through L2 perception training (지각 훈련을 통한 한국어 폐쇄음 음향 신호 가중치의 L2 학습)

  • Oh, Eunjin
    • Phonetics and Speech Sciences
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    • v.13 no.4
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    • pp.9-21
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    • 2021
  • This study investigated whether Korean learners improve acoustic cue weights to identify Korean lenis and aspirated stops in the direction of native values through perception training that focused on contrasting the stops in various phonetic contexts. Nineteen native Chinese learners of Korean and two native Korean instructors for the perception training participated in the experiment. A training group and a non-training group were divided according to pretest results, and only the training group participated in the training for 5 days. To estimate the perceptual weights of the stop cues, a pretest and a posttest were conducted with stimuli whose stop cues (F0 and VOT) were systematically manipulated. Binary logistic regression analyses were performed on each learner's test results to calculate perceptual β coefficients, which estimate the perceptual weights of the acoustic cues used in identifying the stop contrast. The training group showed a statistically significant increase of 0.451 on average in the posttest for the coefficient values of the F0, which is the primary cue for the stop contrast, whereas the non-training group showed an insignificant increase of 0.246. The patterns of change in the F0 use after training varied considerably among individual learners.

Assessment of the impact of gated communities on social sustainability of neighborhoods in Seoul (서울의 빗장주거단지가 근린의 사회적 지속가능성에 미치는 영향 평가)

  • Kim, Hee-Seok;Lee, Young-Sung
    • Journal of the Korean Regional Science Association
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    • v.36 no.1
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    • pp.3-16
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    • 2020
  • Most of the Korean apartment complexes are considered as gated communities having characteristics such as self-sufficiency in service provision, self-governance and exclusiveness. Today the exclusionary features of apartment complexes are reinforced by a new practice of erecting gates against pedestrians in addition to the existing walls without considering implication of the practice over neighborhoods. Three groups of residents, those who live in low-rise residential areas without walls, apartment complexes with walls and apartment complexes with walls and gates were surveyed to measure the impact of the new exclusionary practice of gated communities on social sustainability of neighborhoods. Gates turn out to improve social sustainability indicators related to life quality but lower social cohesion of neighborhoods by lowering inclusiveness indicator considerably. The new apartment complexes with increased exclusiveness shake the established order of co-existence between low-rise residential areas and apartment complexes and strengthen spatial and social segregation within neighborhoods.

SURGICAL REPAIR OF COMPLETE BONY BILATERAL CHOANAL ATRESIA VIA TRANSPALATAL APPROACH (완전 골성 양측성 후비공 폐쇄 환자의 구개부를 통한 외과적 치험례)

  • Kim, Kyoung-Won;Cho, Yong-Seok;Yang, Soo-Nam
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.20 no.2
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    • pp.133-138
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    • 1998
  • Choanal atresia may be membrane or bony, unilateral or bilateral. Approximately 90% of the choanal atresia are bony type. Unilateral choanal atresia often eludes the diagnosis because of the absence of subjective symptoms in the neonatal period. However, bilateral choanal atresia presents at birth with cyclic respiratory distress aggravated by feedings. So complete bilateral choanal atresia is considered as a neonatal emergency. Examinations for the diagnosis of chonal atresia include 1) attempt at passing a rubber catheter or probe through the patient s nose, 2) mirror examination of the nasopharynx, 3) digital examination of the nasopharynx, 4) X-ray examination after installation of radiopaque materal into the nasal cavity. But, computed tomography has become accepted method for evaluation of choanal atresia. Surgical repair of choanal atresia is accomplished via transnasal or transpalatal approach. Advantages of the transpalatal approach are improved exposure and the preservation of mucosal flap along the newly formed apertures. On the other hand, the transpalatal approach carries the risk of injury to the greater palatine neurovascular complex, and requires longer operative time. After careful physical and radiographic examinations, we accomplished the surgical repair of the complete bony bilateral choanal atresia via transpalatal approach without complications.

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Instructional Design Model Study for the Practical Problem-Solving Learning System (실습 문제 풀이 학습시스템을 위한 교수 설계 모형 연구)

  • Kim, JaeSaeng;Jeong, Okhee
    • Proceedings of the Korea Contents Association Conference
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    • 2014.11a
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    • pp.421-422
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    • 2014
  • 최근 네트웤의 발달로 웹기반 강의시스템과 문제풀이 학습법이 많이 도입되고 있다. 이 학습법은 물리적 폐쇄성을 극복하고 학습자의 편이성을 제공하고, 학습자와 교수자간 상호작용성을 높일 수 있으므로 학습효과를 최대로 고양시킬 수 있다. 현재 웹 기반용 학습시스템들은 많이 개발되어 있으나 온라인에서 학습할 수 있는 실습교과목에 대한 교수-학습 모형 개발은 미흡한 편이다. 본 논문에서는 사례로서 실습교과목을 위한 실습문제풀이학습시스템을 위한 교수설계모형을 제안한다.

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