Long-term Stability after Reduction of Mandible Fracture by Keyhole Plate: Evaluation at the Time of Plate Removal

Cheon, Kyeong-Jun,Cho, Seoung-Won,Jang, Won-Seok,Kim, Ju-Won,Yang, Byoung-Eun Korean Association of Maxillofacial Plastic and Re 2020 Maxillofacial Plastic Reconstructive Surgery Vol.42 No.-

Background: Various types of miniplates have been developed and used for the reduction of facial bone fractures. We introduced Yang's Keyhole (YK) plate, and reported on its short-term stability. The purpose of this study was to evaluate the long-term stability of the YK plate, as a follow-up study, by examining the patients who had used the YK plate among the patients with the reduction of mandible fractures and who visited for plate removal. Methods: We reviewed the medical records of 16 patients who underwent mandibular fracture fixation using a YK plate (group I) and 17 patients who underwent mandibular fracture fixation using a conventional plate (group II). Assessment was then made on malunion, occlusal stability, discomfort during the application, and clinical symptoms. Results: From January 2015 to December 2017, a total of 36 patients underwent mandibular fracture surgery using a YK plate. A total of 16 patients received plate removal. Among them, 15 were male and 1 female. The average age was 26 years. The applied surgical sites were the 12 on mandibular angle, 4 on mandibular symphysis, and 2 on subcondyle. The application period of YK plate was an average of 335 days. During the same period, 45 people underwent surgery on the conventional plate. A total of 17 patients received plate removal. Among them, 15 were male and 2 females. The average age was 36 years. The applied surgical sites were the 8 on mandibular angle, 4 on mandibular symphysis, and 2 on subcondyle. The application period of the conventional plate was an average of 349 days. No malocclusion occurred at the time of removal, and occlusion was stable. No patient complained of joint disease or discomfort. Conclusion: The YK plate system, in which the screw was first inserted and the plate was applied, for clinical convenience did not cause any particular problem and no significant difference from the conventional plate.

자판기 시스템 운영문제의 휴리스틱 해법 개발과 평가

박양병(Yang Byung Park),장원준(Won Jun Jang),박해수(Hae Soo Park) 한국산업경영시스템학회 2011 한국산업경영시스템학회지 Vol.34 No.4

The operation of vending machine system presents a decision-making problem which consists of determining the product allocation to vending-machine storage compartments, replenishment intervals of vending machines, and vehicle routes, all of which have critical effects on system profit. Especially, it becomes more difficult to determine the operation variables optimally when demand for a product that is out-of-stock spills over to another product or is lost. In this paper, we propose a heuristic for solving the operation problem of the vending machine system and evaluate it by comparing with Yang’s algorithm on various test problems with respect to system profit via a computer simulation. The results of computational experiments show a substantial profit increase of the proposed heuristic over Yang’s algorithm. Sensitivity analysis indicates that some input variables impact the profit increase significantly.

골수염의 진단에 있어서의 Tc-99m Hexamethylpropylene amine oxime 백혈구 스캔의 임상적 유용성

최상호,김양수,정준원,정진원,추은주,서동대,배인규,양승오,우준희,류지소 대한화학요법학회 2001 대한화학요법학회지 Vol.19 No.1

배경 : 골수염의 진단에 있어 Technetium-99m을 이용한 삼상 골스캔(Tc-99m MDP스캔)은 단순방사선 검사상 정상소견을 보이는 경우에 쓰이는 1차적 검사로 매우 높은 민감도를 보인다. 그러나 Tc-99m MDP 스캔은 골절이나, 정형외과적 삽입물, 신경병적 관절병변과 같이 뼈의 재형성이 증가되는 상황에서도 양성소견을 보여 특이도가 낮은 단점이 있다. 이러한 단점을 보완하고자 골수염의 진단에 있어 Tc-99m HMPAO 백혈구 스캔의 유용성을 알아보고자 하였다. 대상 및 방법 : 골수염이 의심되어 Tc-99m HMPAO 백혈구 스캔을 시행했던 15명의 의무기록을 후향적으로 분석하였다. 골수염의 확진은 임상관찰 소견과 배양검사 결과와 병리소견을 기준으로 하였다. 결과 : 골수염의 진단에 있어 Tc-99m HMPAO 백혈구 스캔의 민감도와 특이도는 각각 100%와 78%였고 Tc-99m HMPAO 스캔의 경우는 100%와 18%였다. 가장 흔한 원인균은 methicillin-resistant S. aureus였다. Tc-99m MDP 스캔에서 양성소견을 보였던 환자중 3명의 환자가 Tc-99m HMPAO 백혈구 스캔에서 음성 소견을 보였으며 이 환자들은 추적관찰상 골수염이 없는 것으로 확인되었다. 결론 : Tc-99m HMPAO 백혈구 스캔은 골수염의 존재를 진단하는데 있어 민감도와 특이도가 높으며, 특히 뼈의 재형성이 증가되어 Tc-99m MDP 스캔의 특이도가 낮게 나타나는 상황에서 유용하리라 사료된다. Background Three phase bone scintigraphy, performed with technetium-labeled diphosphonates (Tc-99m MDP scan), is the very sensitive radionuclide procedure of choice for diagnosing osteomyelitis. But, Tc-99m MDP scan is less specific when bone remodeling is increased. To overcome this limitation, we evaluated the diagnostic value of technetium-99m hexamethylpropyleneamine oxime (HMPAO) labeled leukocyte scan in osteomyelitis. Methods : We retrospectively reviewed 15 patients with suspected osteomyelitis who performed Tc-99m HMPAO labeled leukocyte scan. The diagnosis of osteomyelitis was based on clinical course and bacterial culture, and pathologic findings. Results The sensitivity and specificity of Tc-99m HMPAO leukocyte scan was 100% and 78%, and those of Tc-99m MDP scan was 100% and 18%, respectively. The most common organism was Methicilein-Resistant S. aureus. Among the patients that showed persistent accumulation on Tc-99m MDP scan, three patients showed no uptake on Tc-99m HMPAO leukocyte scan and these patients were confirmed that had no osteomyelitis. Conclusion : Tc-99m HMPAO leukocyte scan is a useful test for determining the presence or absence of osteomyelitis, especially under condition that bone remodelin is increased.

Neisseria elongata subsp. nitroreducens 에 의한 감염성 심내막염 1 예

원선영,정두련,주광로,이미숙,조용균,김은옥,김양수,우준희,배직현,류지소 대한화학요법학회 1998 대한화학요법학회지 Vol.16 No.2

Neisseria elongata subsp. nitroreducens는 Neisseria elongata의 세 가지 아종 중에서 인체에 병원균으로 작용하는 세균으로서 주로 심내막염을 일으키며 드물기는 하지만 그 증례 수가 점차 증 가하고 있으며 국내에서는 아직 보고된 바가 없었다. 저자들은 이전에 심질환의 병력이 없던 36세의 남자에서 치과치료 후 발생한 N. elongata subsp. nitroreducens에 의한 심내막염을 경험하여 문헌고찰과 함께 보고하는 바이다. N. elongata subsp. nitroreducens에 의한 심내막염은 경과 중 판막 파괴를 많이 초래하여 판막치환술이 필요했던 경우가 많았던 것의로 보고되고 있으나 본 증례에서는 4주간의 항균제 치료만으로 합병증 없이 호전되었다. Neisseria elongata subsp. nitroreducens differs from the other subspecies of N. elongata in additional reduction of nitrate without gas formation. Like most Neisseria, species except Neisseria meningitidis and Neisseria gonorrheae, N. elongata subsp. nitroreducens is usually classified in the group of non-pathogenin Nisseria. However, N. elongata subsp. nitroreducens, usual commensal of nasopharynx, can cause serious infections, usually endocarditis. To date, infective endocarditis with N. elongata subsp. nitroreducens has not been reported in Korea. We report a case of 36 year-old Korean male with Neisseria elongata subsp. nitroreducens endocarditis who was treated with antimicrobial agents without complication.

압력용기강의 천이온도 영역에서 파괴인성 평가에 RKR Model의 적용

양원준,李奉相,洪俊和,許武榮 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.4

Fracture toughness of a SA 533 B-1 steel was characterized in ductile-brittle transition temperature region by means of a RKR-type model. The original RKR model has been used to predict the plane strain fracture toughness(K_IC) behaviors in lower shelf region by assuming two material parameters, ie, the critical fracture stress and the characteristic distance. In this study, the fracture surface of every specimen was thoroughly investigated using scanning electron microscope to locate the actual cleavage initiation and to measure the cleavage initiation distance(CID) from the initial crack. The local fracture stress(σ^*_f) of material was determined from the elastic-plastic stress field at the measured cleavage initiation location in the notched and precracked specimen. The local fracture stress of the precracked specimens was much higher than that of the notched specimen. The measured CIDs were strongly dependent on the test temperature and also on the fracture toughness. Based on the observations, it is found that, in the RKR-type cleavage fracture models, the characteristic distance should not be treated as a constant material parameter in the ductile-brittle transition region where the cleavage initiation controls the overall fracture process.

BiCMOS 반전기의 입출력특성 및 신호지연시간 연구

전영환,강양원,홍창희 동아대학교 공과대학 부설 한국자원개발연구소 1990 硏究報告 Vol.14 No.2

In this paper, BiCMOS(a combinded bipolar and CMOS) buffer is analyzed and characterized in terms of input, output characteristics and propagation delay times. These approximation responses are compared to those determinded by SPICE simulations and the agreement is satisfactory. As a result, BiCOMS has a larger driving capability than MOS transistor. (approximatly a dc current gain β times bipolar transistor.)

Multiplates : Low profile Antennas

양준원 대불대학교 1999 論文集 Vol.5 No.1

이동통신이나 위성통신에서 사용되는 송수신 장치는 날로 발전되어 가고 있으며 그것을 구성하는 장비들은 경량화, 소형화, 고성능화를 추구하고 있는 실정이다. 송수신 장치중 하나인 안테나 또한 이러한 요구를 만족해야 할 필요성이 높아지고 있다. 위의 조건을 만족하는 안테나의 하나로서 낮은 높이(低姿勢)와 輕量이면서 광대역의 대역폭의 특징을 가진 積層板狀안테나가 있다. 이 안테나는 2층의 평행평판으로 구성하여, 각 평판 사이의 공간에서 복수의 공진을 발생시켜 광대역화를 실현시킨 안테나이다. 그러나 평판 안테나의 해석 측면에 눈을 돌려보면 평판상의 전류분포를 구해야하는 어려움이 있어 기존의 해석방법으로는 그 해석 예를 찾아보기 어렵다. 근대에 들어 전자계해석의 신기원이라 할 수 있는 새로운 해석법으로 FDTD법이 소개되고 있고, 컴퓨터의 발전과 더불어 전자계, 안테나해석법으로서 자리 매김을 하고 있다. 따라서 본 논문에서는 FDTD법을 이용하여 적층판상 안테나를 해석함으로써 안테나의 동작을 보다 분명하게 규명하고, 실제적으로 안테나를 제작 실험하여 그 해석의 타당성을 증명하고 있다.

만성 부비동염에서 섬모운동과 전산화 단층촬영에서의 상악동 점막비후의 상관관계

민양기,전상준,이재서,이철회,이강수,윤자복,이원진,박광석 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.7

FDTD법을 이용한 광대역 鼎型안테나 해석

양준원 대불대학교 2001 論文集 Vol.7 No.1

A multiplates : low profile antenna has wide-band characteristics. No theoretical analysis has been on the multiplates antenna of it's complicated structure. In this paper, kanae type antenna was studied using FDTD method. The calculated band width of this antenna is 55.6%(VSWR<2.0) and the sizeble reduction ratio is 0.0122. The radiation pattern is null in the upper side and omni-directional in the horizontal direction.

마이크로스트립 線路에서의 放射

양준원 대불대학교 2002 論文集 Vol.8 No.1

The problem of radiated emission from printed circuit boards is serious topic. Trace on the printed circuit board has a quite similar behavior as one for microstrip line used in a microwave region. The coupling problem of external waves to transmission line has been studied by using transmission-line theory. The radiation problems is considered to be in a reciprocal relationship between both problems. Therefore, the radiation problems is reciprocal theory. The coupling for microstrip lines can be predicted by studying electromagnetic fields propagation inside the dielectric substrate. the experimental results for the radiation are good agreement whit the predicted.