• 제목/요약/키워드: Rigid method

검색결과 1,790건 처리시간 0.032초

Trans-sinusoidal maxillary distractor($TS-MD^{(R)}$)를 이용한 구순구개열 환자에서의 상악골 골신장술 (Maxillary Distraction Osteogenesis Using $TS-MD^{(R)}$ (Trans-sinusoidal Maxillary distractor) on Cleft Patients)

  • 팽준영;이일구;명훈;황순정;서병무;최진영;이종호;정필훈;김명진
    • 대한구순구개열학회지
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    • 제8권2호
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    • pp.71-79
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    • 2005
  • Purpose: Maxillary hypoplasia is a common developmental problem of cleft lip and palate. Fair results with distraction osteogenesis have been reported especially when these patients need a large amount of maxillary advancement, instead of orthognathic surgery. The purpose of this study is to evaluate the clinical results with a relatively new distractor, $TS-MD^{(R)}$ (Trans-sinusoidal maxillary distractor, KLS Martin, Tuttlingen, Germany) which was used for the advancement of the maxilla in the cleft patients. Patients and Method: Distraction osteogenesis using $TS-MD^{(R)}$ was performed for four CLP patients (three males and one female) who had maxillary hypoplasia. All patients were over 16 years old. As three patients showed mandibular prognathism as well, bilateral sagittal split ramus osteotomy for mandibular setback was performed at the same time. After consolidation periods of 4 to 12 weeks, the distraction devices were removed and miniplates were placed for simultaneous internal fixation. Results: Three patients showed a large amount of incisal overbite but one patient did not have sufficient maxillary advancement. Le Fort I osteotomy, maxillary advancement and internal fixation should have been performed for the patient when removing the distraction devices. Different from the $clinician{\box}s$ expectation, the amount of maxillary advancement using $TS-MD^{(R)}$ was not sufficient, although the device has rigid mechanical property. Rotation of maxilla during distraction forward and downward was also observed. Conclusion: Even though the maxillary advancement with $TS-MD^{(R)}$ device could be achieved, the clinical control of some characteristics related with the device was necessary. More clinical studies on $TS-MD^{(R)}$ should be performed.

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현대적 응용을 위한 한국 전통무적의 선호도 및 이미지 평가 (Preference and Evaluation of Image for Modern Application of Korean Traditional Patterns)

  • 조지현;김영은
    • 한국생활과학회지
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    • 제10권4호
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    • pp.399-409
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    • 2001
  • The purpose of this study was to evaluate the preference of image for modern application of Korean traditional patterns. A survey was conducted using the random selection among female undergraduate students in Daegu city. The degree of interest and preference in Korean traditional style or something like that measured by 5 scale method. And then they were classified into two groups which were interest/non-interest group, and preference/non-preference group. The image of Korean traditional patterns consisted of semantic differential scales. Frequency, percentage and mean were analyzed, for difference of groups t-test was analyzed. The results were as fellows; 1. For the degree of interest for Korean traditional patterns, it was showed that 53.8% of total respondents took interest and about 40.4% of them had preference for traditional patterns. the correlation coefficient of the degree of interest and preference was 0.782(p<0.01) and showed that the positive correlation was high. 2. Among 20 kinds of Korean traditional patterns, the degree of preference for the patterns of plants and nature was quite high whereas that for the patterns of geometrical things was low relatively. 3. It was evaluated that pattern of nature was fresh, refined and womanly image generally. It was evaluated that pattern of plants was womanly, fresh, weak, light and soft image and that of animals was heavy, splendid, high-class, manly, strong and positive image. It was evaluated that pattern of geometrical things was the most refined image and high-class, rigid and strong. 4. The statistical significance of mean between interest/non-interest group was showed statistically in the patterns of clouds, mountains, lotus, apricot, orchid, dragon, phoenix and bogey. In case of pattern of orchids, the degree of preference was most different between interest/non-interest group. 5. The pattern of plants showed the most different evaluation for images between interest/non-interest group. For refined/old-fashioned polar adjective images, the interest group evaluated the pattern of plants more refined. 6. For pattern of orchids, the difference of degree of preference between preference/non-preference group was most remarkable in Korean traditional patterns. 7. The pattern of geometrical things showed the most different evaluation for images between preference/non-preference group. For warm/cool polar adjective images, the preference group evaluated the pattern of geometrical things cooler.

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수면하 보오텍스 유동과 자유표면과의 상호 작용에 관한 연구 (Numerical and Experimental Investigation on the Interaction of Subsurface Vortical Flows with a Free Surface)

  • 송무석
    • 대한조선학회논문집
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    • 제30권2호
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    • pp.76-85
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    • 1993
  • 자유표면과 수면하 vortex 유동과의 상호작용으로 생기는 수면위의 특이 형상을 실험과 수치해석으로 얻어진 결과에 근거하여 논하였다. 먼저 2차원적인 실험이나 해석적인 연구로 이해될 수 있는 "striation"의 발생을 살펴 본다. "Scar"라 불리우는 striation과 수직한 형상은 2차원 vortex filament와 vortex pair 생성시 생겨나는 residual vortex의 상호작용으로 설명하였다. 간단하면서도 중요한 상호작용의 역학을 연구할 목적으로 vortex ring이 자유표면과 수직하게 충돌할 경우에 나타나는 현상들을 실험적으로 논하였고 이때 상호작용의 초기단계를 축대칭 문제로 하여 수치해석적으로 얻어진 결과와 비교하였다. 상호작용의 후기단계는 vortex reconnection을 포함하는 복잡한 과정인데 이때 수면에서의 짧은파 생성을 vortex ring의 수면과의 경사진 충돌로 설명하였다. 또한 위의 수면과 생성을 간단한 해석적 model로 재구성하여 비교해 보았다. 끝으로 수면위에 존재하는 오염물질이 수면하 vortex 유동에 미치는 영향을 수치해석적인 방법으로 free slip및 rigid wall 조건의 경우와 비교하여 살펴보았다.

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Fitting accuracy of ceramic veneered Co-Cr crowns produced by different manufacturing processes

  • von Maltzahn, Nadine Freifrau;Bernhard, Florian;Kohorst, Philipp
    • The Journal of Advanced Prosthodontics
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    • 제12권2호
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    • pp.100-106
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    • 2020
  • PURPOSE. The purpose of this in vitro study was to evaluate the fitting accuracy of single crowns made from a novel presintered Co-Cr alloy prepared with a computer-aided design and computer-aided manufacturing (CAD/CAM) technique, as compared with crowns manufactured by other digital and the conventional casting technique. Additionally, the influence of oxide layer on the fitting accuracy of specimens was tested. MATERIALS AND METHODS. A total of 40 test specimens made from Co-Cr alloy were investigated according to the fitting accuracy using a replica technique. Four different methods processing different materials were used for the manufacture of the crown copings (milling of presintered (Ceramill Sintron-group_cer_sin) or rigid alloy (Tizian NEM-group_ti_nem), selective laser melting (Ceramill NPL-group_cer_npl), and casting (Girobond NB-group_gir_nb)). The specimens were adapted to a resin model and the outer surfaces were airborne-particle abraded with aluminum oxide. After the veneering process, the fitting accuracy (absolute marginal discrepancy and internal gap) was evaluated by the replica technique in 2 steps, before removing the oxide layer from the intaglio surface of the crowns, and after removing the layer with aluminum oxide airborne-particle abrasion. Statistical analysis was performed by multifactorial analysis of variance (ANOVA) (α=.05). RESULTS. Mean absolute marginal discrepancy ranged between 20 ㎛ (group_cer_npl for specimens of Ceramill NPL) and 43 ㎛ (group_cer_sin for crowns of Ceramill Sintron) with the oxide layer and between 19 ㎛ and 28 ㎛ without the oxide layer. The internal gap varied between 33 ㎛ (group_ti_nem for test samples of Tizian NEM) and 75 ㎛ (group_gir_nb for the base material Girobond NB) with the oxide layer and between 30 ㎛ and 76 ㎛ without the oxide layer. The absolute marginal discrepancy and the internal gap were significantly influenced by the fabrication method used (P<.05). CONCLUSION. Different manufacturing techniques had a significant influence on the fitting accuracy of single crowns made from Co-Cr alloys. However, all tested crowns showed a clinically acceptable absolute marginal discrepancy and internal gap with and without oxide layer and could be recommended under clinical considerations. Especially, the new system Ceramill Sintron showed acceptable values of fitting accuracy so it can be suggested in routine clinical work.

북한산국립공원 북한산성-인수봉 지역의 산림군집구조 (Vegetation Structure of Mountain Ridge from Bukhansansung to Insubong in the Bukhansan National Park, Korea)

  • 추갑철;엄태원;김갑태;박삼봉;안효현;김남호;김희정
    • 한국환경생태학회지
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    • 제22권2호
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    • pp.98-105
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    • 2008
  • 북한산 국립공원지역의 식생구조를 파악하고자, 북한산성에서 인수봉에 이르는 지역에 16개의 방형구$(2500m^2)$를 설정하여 식생을 조사하였다. 식물군집을 분류한 결과 16개 조사구는 신갈나무 혼효림 군집, 소나무신갈나무 군집, 신갈나무 우점군집의 3개 군집으로 분류되었다. 북한산 국립공원내 북한산성에서 인수봉에 이르는 지역의 우점수종은 신갈나무로 나타났다. 수종간의 상관관계는 신갈나무와 진달래, 신갈나무와 개옻나무, 진달래와 철쭉, 노린재나무와 철쭉, 당단풍과 함박꽃나무 등의 수종들 간에는 높은 정의상관이 인정 되었고, 물푸레나무와 진달래, 노간주나무와 당단풍, 쪽동백나무와 당단풍 등의 수종들간에 부의 상관이 비교적 높은 편이다. 조사지의 군집별 종 다양성도는 $1.236\sim1.319$의 범위로 다른 국립공원들의 능선부 식생에 비하여 비교적 높게 나타났다.

하악골 전돌증환자의 구내 하악골상행지 수직골절단술후 이하두정 계측방사선사진상에서의 근심골편의 형태 및 위치 변화 (MORPHOLOGIC AND POSITIONAL CHANGE OF THE PROXIMAL SEGMENTS AFTER INTRAORALVERTICAL RAMUS OSTEOTOMY OF THE MANDIBULAR PROGNATHISM ON SUBMENTOVERTEX CEPHALOGRAM)

  • 정재형;박형식;황충주
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제29권1호
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    • pp.26-34
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    • 2003
  • Intraoral Vertical Ramus Osteotomy,along with Sagittal Split Ramus Osteotomy,is an popular surgical technique performed on mandibular prognathism. However Intraoral Vertical Ramus Osteotomy has been suspected for an initial mobilization at the healing phase of segment because it does not employ the rigid fixation between segments. To execute a study on the healing phase of segment after Intraoral Vertical Ramus Osteotomy on the horizontal plane, 102 patients (204 parts) who were diagnosed mandibular prognathism and took Intraoral Vertical Ramus Osteotomy at the Yonsei University dental hospital were observed during the period of before operation, immediately postoperation, 1 month, 3 months, 6 months, and 12 months. The change in the width of segment and horizontal angle of proximal segment and condylar head on the Submentovertex Cephalogram taken from those patients represented following results. 1. The width of proximal and distal segment decreased with the lapse of time. It decreased into 84.5% between immediate postoperative and 6M and even continued to decrease till 12M. 2. The horizontal angle of the proximal segment did medial rotation according as the lapse of time and rigorously continued till 3M. The rotation angle of condylar head indicated its tendency of recurrence to the original position but the entire recurrence was not allowed. The bigger an initial angle was, the higher was the tendency of recurrence after the operation while the rotation angle remained still bigger. 3. After grouping into group 1, group 2,and group 3 based on the extent of the variation of rotation angle of condylar head at immediate postoperative, the variation of rotation angle was measures in each group. The result presented that the initial rotation angle of condylar head had correlation with that of proximal segment but had no relation with the extent of setback of the mandible. However a quantitative analysis alone is not a sufficient method for analyzing the healing phase of segment on the horizontal plane.Therefore a multilateral analysis using 3 dimensional data such as CT is recommendable for the future study.

Wolter 금속판를 이용한 제 2형 원위부 쇄골 골절의 치료 (Treatment of Type 2 Distal Clavicle Fracture using Wolter Plate)

  • 신성일;송경원;이진영;이승용;김갑래;현윤석;이광남;이은수
    • Clinics in Shoulder and Elbow
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    • 제12권1호
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    • pp.14-20
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    • 2009
  • 목적: 본 연구는 Wolter 금속판을 이용한 제 2형 원위부 쇄골 골절 치료의 임상적 결과를 평가하고자 하였다. 대상 및 방법: 2004년부터 2007년까지 Wolter 금속판으로 치료한 제 2형 원위부 쇄골 골절을 가진 16명의 환자를 대상으로 하였다. 평균 나이는 32.6세 이었고, 수술 후 평균 추시 기간은 22.9 개월이었다. 정복 및 골유합의 평가는 수술 직후 및 최종 방사선 소견을 이용하였고, 기능적 평가는 Kona의 기능적 평가 기준 및 Constant 점수를 사용하였다. 결과: Kona의 기능적 평가기준에 의해 우수 12예, 양호 3예, 보통 1예의 결과를 보였으며 Constant 점수는 평균 90점을 보였다. 16예 모두에서 골 유합을 확인하였으며, 합병증으로는 1예에서 금속판의 갈고리 부분이 돌출되어 피부에서 촉지 되었으며, 1예에서 견봉 골절이 발생하였으나 2예 모두 만족할 만한 골유합 소견을 보였으며, 그 외 견봉-쇄골 관절의 관절염, 감염증 등 다른 합병증은 관찰되지 않았다. 결론: 제 2형 원위부 쇄골 골절에서 Wolter 금속판을 이용한 고정법은 쉽게 만족스런 정복과 견고한 고정을 얻을 수 있고, 불유합의 발생이 적으며, 임상적 결과가 우수한 수술 방법이라고 생각된다.

잠김 압박 금속판(LCP)을 이용한 상완골 근위부 이분 및 삼분 골절의 치료 (Treatment of Two- and Three-Part Fracture of Proximal Humerus using LCP)

  • 신성일;송경원;이진영;이승용;김갑래;현윤석;박덕용
    • Clinics in Shoulder and Elbow
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    • 제10권2호
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    • pp.204-211
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    • 2007
  • 목적: 본 연구는 잠김 압박 금속판(LCP)을 이용한 상완골 근위부 골절 치료의 결과와 합병증을 평가하고자 하였다. 대상 및 방법: 2004년 부터 2006년 까지 잠김 압박 금속판으로 치료한 상완골 근위부의 이분 골절과 삼분 골절을 가진 21명의 환자를 대상으로 하였다. 평균 나이는 54.9세 였다. 술후 평균 추시 기간은 22.9개월 이었다. 정복과 합병증의 평가는 최종 방사선 소견을 이용하였고, 기능적 평가는 Neer의 기능적 평가기준을 사용하였다. 결과: Neer의 기능적 평가기준에 의해 견관절 기능의 평균 점수는 86.3 이었고, 18예에서 만족스러운 결과를 보였다. 불유합은 1예 발생하였으며, 상완골 두의 감염이나 무혈성 괴사는 없었다. 최종 결과와 골절의 유형, 나이, 성별 또는 정복의 양상과는 임상적 연관을 보이지 않았다. 결론: 본 연구에서는 상완골 근위부 골절의 치료에서 잠김 압박 금속판 고정으로 만족스러운 결과를 얻었다. 상완골 근위부 골절의 치료에서 잠김 압박 금속판을 이용한 고정은 만족스러운 정복, 강한 고정 그리고 조기 관절 운동을 얻는 좋은 방법이라고 생각된다.

접합부 강성을 고려한 합성 모듈러 시스템의 내진 성능평가 (Seismic Performance Assessment of a Composite Modular System Considering Stiffness of Connections)

  • 최영후;이호찬;김진구
    • 한국구조물진단유지관리공학회 논문집
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    • 제22권2호
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    • pp.105-114
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    • 2018
  • 모듈러 시스템은 하중저항 방식에 따라 개방형 모듈러 및 폐쇄형 모듈러 분류가 된다. 그 중 개방형 모듈러는 폐쇄형 단면을 갖고 있어 부재간의 접합 및 모듈간의 접합을 하는데 제약이 있다. 이에 Choi et al.(2017)은 절골형 단면 안에 콘크리트를 채운 합성 모듈러 시스템을 제안하였다. 하지만 모듈간 접합을 강접으로 가정하여 접합부 거동에 의해 구조물 전체에 미치는 영향을 파악하지 못하였다. 본 연구에서는 유한요소해석을 하여 제안된 모듈러의 접합부 강성을 산정하였다. 성능 검증을 위해 FEMA 440의 선형화방법을 사용하여 접합부 강성 유, 무에 따른 구조물의 내진성능을 파악하였다. 해석결과에 따르면 접합부 강성을 고려한 모델의 보유 내력 및 층간변위비가 접합부 강성을 고려하지 않은 모델에 비해 현저하게 감소하는 것으로 나타났다. 이를 토대로 접합부의 강성이 전체 구조물 거동에 영향을 미치는 것으로 판단된다.

Assessment of Perspective Development of Transport and Logistics Systems at Macro and Micro Level under the Conditions of Industry 4.0 Integration

  • Maiboroda, Olha;Bezuhla, Liudmyla S.;Gukaliuk, Andrii F.;Shymanska, Viktoriia;Momont, Tetiana;Ilchenko, Tetiana V.
    • International Journal of Computer Science & Network Security
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    • 제21권3호
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    • pp.235-244
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    • 2021
  • The change of the development of transport and logistics systems occurs with the active change of technology and the advent of the era of Industry 4.0. It requires modernization of approaches to the development of transport and logistics systems at the macro and micro levels. The present study aims to identify perspective directions of development and evolution, find out the existing obstacles in the integration of technological solutions of transport and logistics systems at the macro and micro levels. This study is based on a quantitative and qualitative methodology for assessing the level of integration of technologies into transport and logistics systems to study the prospects for their development at the micro level. Macroeconomic indicators of transport and logistics in the context of different regions of the world were used to quantify the development prospects. For a qualitative assessment of the development of the transport and logistics system, the case study method was used. The object of the study was selected logistics company Sensco Logistics Inc., Austin TX. At the macro level, countries with more innovative logistics sectors have stronger mechanisms for coordinating private sector activities. Simplification of administrative procedures of control and regulation by the public sector in order to facilitate trade between countries is a promising direction for the development of transport and logistics systems. Such reforms are more effective in developing a "rigid" transport infrastructure. The integration of Industry 4.0 technology solutions into the international logistics sector is defined by political and legal barriers, especially in developing countries. In low-income countries, hard and soft infrastructure reforms are hindering the development of logistics companies that provide transport services. This determines the national level of development of transport and logistics systems, and in general the global level of development of transport and logistics. In developed countries, the legal barriers to the development of new technological logistics are environmental requirements for the integration of technologies into the transport system. These trends are slowing down the development of International Logistics, which, compared to other industries, is slower to integrate Industry 4.0 technologies. This study combines macroeconomic factors that determine the prospects for the development of transport and logistics systems at the micro level.