• Journal of Korean Neurosurgical Society
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• 제52권6호
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• pp.541-546
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• 2012

Objective : The prefabrication of customized cranioplastic implants has been introduced to overcome the difficulties of intra-operative implant molding. The authors present a new technique, which consists of the prefabrication of implant molds using three-dimensional (3D) printers and polymethyl-methacrylate (PMMA) casting. Methods : A total of 16 patients with large skull defects (>100 $cm^2$) underwent cranioplasty between November 2009 and April 2011. For unilateral cranial defects, 3D images of the skull were obtained from preoperative axial 1-mm spiral computed tomography (CT) scans. The image of the implant was generated by a digital subtraction mirror-imaging process using the normal side of the cranium as a model. For bilateral cranial defects, precraniectomy routine spiral CT scan data were merged with postcraniectomy 3D CT images following a smoothing process. Prefabrication of the mold was performed by the 3D printer. Intraoperatively, the PMMA implant was created with the prefabricated mold, and fit into the cranial defect. Results : The median operation time was $184.36{\pm}26.07$ minutes. Postoperative CT scans showed excellent restoration of the symmetrical contours and curvature of the cranium in all cases. The median follow-up period was 23 months (range, 14-28 months). Postoperative infection was developed in one case (6.2%) who had an open wound defect previously. Conclusion : Customized cranioplasty PMMA implants using 3D printer may be a useful technique for the reconstruction of various cranial defects.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제37권
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• pp.9.1-9.7
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• 2015

Background: This study are to identify the symptomatic changes and condylar stability after 2 jaw surgery without preceding treatments for Temporomandibular joints(TMJ) in class III patients with the TMJ symptoms; and to assess therapeutic effect of 2 jaw surgery and the necessity of preceding treatment for alleviation of TMJ symptoms. Methods: 30 prognathic patients with preexisting TMJ symptoms were divided into 2 groups according to presence or absence of preceding treatments before the surgery. We evaluated symptomatic changes on both TMJ by questionnaires and clinical examinations. And we reconstructed 3D cone beam computed tomography images before 2 jaw surgery, immediately after the surgery, and 6 months or more after the surgery with SimPlant software, and analyzed the stability of condylar position on 3D reconstruction model. Significances were assessed by the Wilcoxon signed rank test on SPSS ver. 20.0. Results: Both groups had favorable changes of TMJ symptoms after orthognathic surgery. And postoperative position of condyle had good stability during follow-up period. Conclusion: 2 jaw surgery without preceding treatments for TMD can have therapeutic effect for TMD patients with class III malocclusion.

• 한국지형공간정보학회:학술대회논문집
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• 한국지형공간정보학회 2002년도 춘계학술대회 논문집
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• pp.145-149
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• 2002

CORONA는 미국이 1960년에서 1972년까지 냉전시대 관심지역에 대한 첩보영상을 취득하기 위하여 운영한 영상취득시스템으로 1995년 일반에 자료가 공개됨에 따라 과거의 고해상도 영상자료를 이용할 수 있는 길이 열리게 되었다. 그러나 현재까지 CORONA 영상처리를 위한 모듈을 제공하는 원격탐측 소프트웨어가 개발되어 있지 않기 때문에 CORONA 영상을 이용하여 수치표고모형이나 정사영상을 제작하기 위해서는 적절한 모델링 방법이 필요하다. CORONA 영상은 파노라마 영상으로 필름 가장자리로 갈수록 왜곡이 많이 생기며 사진기 지표가 없고 위성의 궤도와 위치, 자세, 속도, IMC(Image Motion Compensation)에 대한 자세한 자료를 제공하지 않는 문제점이 있다. 따라서 본 논문에서는 지형복원을 위하여 지상기준점을 이용하는 2가지 모델링 방법을 이용하였다. 첫 번째는 파노라마 왜곡과 촬영 비행체 이동에 의한 왜곡, IMC에 의한 왜곡을 보정하는 모형식을 구성하여 이용하였으며, 두 번째는 위성과 센서에 대한 정보를 필요로 하지 않는 다항식비례모형(RFM; Rational Function Model)을 이용하였다. 대상지역은 서울지역의 입체영상으로 대략 $33km{\times}26km$ 지역이다. 영상은 지상해상도 약 2.7m로 스캐닝하였고 1:1000 수치지도를 통해 20개의 기준점과 36개의 검사점을 관측하였다. 검사점의 위치정확도를 평가해 본 결과 첫 번째 방법은 수평방향으로 평균 3.9m(X), 2.8m(Y)의 오차를 보였으며 표고의 경우 4.2m의 오차를 보여주었다. 두 번째 방법은 수평방향으로 평균 3.2m(X), 2.8m(Y)의 오차를 보였으며 표고의 경우 5.5m의 오차를 보여주었다. 지형복원 정확도를 검증하기 위하여 첫 번째 방법을 이용하여 대상지역 중 일부인 서울 남산지역에 대해 정사영상과 10m간격의 DEM을 제작하였으며 1:1000 수치지도를 통해 제작된 DEM과 비교한 결과 총 43990개 격자점의 표고 차이는 평균 5.98m였다.

• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.23-36
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• 2009

In the present work, the metabolic network of primary metabolism of the slow-growing myxobacterium Sorangium cellulosum was reconstructed from the annotated genome sequence of the type strain So ce56. During growth on glucose as the carbon source and asparagine as the nitrogen source, So ce56 showed a very low growth rate of $0.23\;d^{-1}$, equivalent to a doubling time of 3 days. Based on a complete stoichiometric and isotopomer model of the central metabolism, $^{13}C$ metabolic flux analysis was carried out for growth with glucose as carbon and asparagine as nitrogen sources. Normalized to the uptake flux for glucose (100%), cells recruited glycolysis (51%) and the pentose phosphate pathway (48%) as major catabolic pathways. The Entner-Doudoroff pathway and glyoxylate shunt were not active. A high flux through the TCA cycle (118%) enabled a strong formation of ATP, but cells revealed a rather low yield for biomass. Inspection of fluxes linked to energy metabolism revealed that S. cellulosum utilized only 10% of the ATP formed for growth, whereas 90% is required for maintenance. This explains the apparent discrepancy between the relatively low biomass yield and the high flux through the energy-delivering TCA cycle. The total flux of NADPH supply (216%) was higher than the demand for anabolism (156%), indicating additional reactions for balancing of NADPH. The cells further exhibited a highly active metabolic cycle, interconverting $C_3$ and $C_4$ metabolites of glycolysis and the TCA cycle. The present work provides the first insight into fluxes of the primary metabolism of myxobacteria, especially for future investigation on the supply of cofactors, building blocks, and energy in myxobacteria, producing natural compounds of biotechnological interest.

• 환경영향평가
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• 제20권5호
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• pp.729-745
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• 2011

The purpose of this paper is to estimate the external diseconomies of an unwelcomed facility on the nearby houses. The facility and the area studied are Dangin-Ri power plant in Mapo-Gu, Seoul and the residential district surrounding it respectively. The nearby housing prices have been changed according to the time and circumstances of the public announcements about the reconstruction or removal plans of the plant. These price changes are regarded as the capitalized values of the external diseconomies due to the plant. This study is based on the hedonic price theory in order to estimate the diseconomies in monetary value. The tools for the estimation are four models of multiple regression with the transaction price as the dependant variable and various housing characteristics including the external effects of the plant as the independent variables. The sample analyzed is 833 house transactions for the past 5 years in the research area. The facts found are as follows; First, the most suitable functional form for the estimation is confirmed to be the linear model. Second, there are significant differences in influence on the housing values among the independent variables, that is, locational characteristics, physical features, and environmental changes with time. Third, the external diseconomy is estimated as \80,137,807 in case that the plant would be reconstructed in the underground of the present site, whereon a substitutional public park would be constructed and as \59,142,248 in case that the plant would move away.

• 한국제4기학회지
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• 제22권1호
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• pp.28-36
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• 2008

The present study has focused on the environmental changes and evidences for sedimentation in the Lake Khuvsgul catchment during the Holocene period, inferred from short core sediment (BO03) from the eastern shore of Borsog Bay, which were analyzed in order to review records of the Holocene climatic evolution and Holocene history in Northern Mongolia. For the purpose of reconstruction of natural phenomenon that occurred in the lake catchment system during the Holocene, physical and chemical properties including HCl-soluble material, biogenic silica, organic matter and grain size distribution of minerals in the core sediments have been analyzed in this study. The vertical variations in composition for these properties show distinctly that five lines of paleoenvironmental evidence occurred in the lake catchment during the Holocene. A modified age model resulting from AMS carbon dating for the BO03 core sediment shows timings of these environmental events at 9.5 Kyr BP, 8.0 Kyr BP, 5.6 Kyr BP and 3.2 Kyr BP, respectively. Paleoenvironmental changes in the Lake Khuvsgul catchment system during the Holocene highlight distinctive features of the hydrological regime and geomorphologic evolution in the lake catchment due to regional landscape and global climatic changes corresponding with the Holocene optimum and thermal optimum. In particular, the change of hydrologic regime based on the sedimentological evidence has been caused by not only overland flow due to melting water, but also base flow due to thick permafrost around Khuvsgul region.

• Korean Journal of Geomatics
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• 제5권1호
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• pp.7-19
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• 2005

Photogrammetric mapping procedures have gone through major developments due to significant improvements in its underlying technologies. The availability of GPS/INS systems greatly assist in direct geo-referencing of the acquired imagery. Still, photogrammetric datasets taken without the aid of positioning and navigation systems need control information for the purpose of surface reconstruction. Point features were, and still are, the primary source of control for the photogrammetric triangulation although other higher-order features are available and can be used. LIDAR systems supply dense geometric surface information in the form of three dimensional coordinates with respect to certain reference system. Considering the accuracy improvement of LIDAR systems in the recent years, LIDAR data is considered a viable supply of photogrammetric control. To exploit LIDAR data, new challenges are poised concerning the representation and reference system by which both the photogrammetric and LIDAR datasets are described. In this paper, registration methodologies will be devised for the purpose of integrating the LIDAR data into the photogrammetric triangulation. Such registration methodologies have to deal with three issues: registration primitives, transformation parameters, and similarity measures. Two methodologies will be introduced that utilize straight-line and areal features derived from both datasets as the registration primitives. The first methodology directly incorporates the LIDAR lines as control information in the photogrammetric triangulation, while in the second methodology, LIDAR patches are used to produce and align the photogrammetric model. Also, camera self-calibration experiments were conducted on simulated and real data to test the feasibility of using LIDAR patches for this purpose.

• 한국측량학회지
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• 제30권2호
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• pp.117-124
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• 2012

최근에 노후화된 도시정비사업으로 토지의 집약적 이용을 위해 아파트 및 공동주택을 초고층 및 고층 아파트 구조물로 재건축 승인함에 따라 인근 주거지역의 일조권 침해에 따른 사회문제로 대두되고 있다. 특히, 교육시설에 있어서의 일조량 침해에 따른 교육환경 여건은 많은 문제점을 내포하고 있다. 따라서, 본 연구에서는 이러한 교육환경 일조량 분석을 위해 Auto $CAD^{(R)}$ 프로그램을 이용하여 교육시설물에 대하여 3차원 모델링으로 구성하였다. 그리고, 시뮬레이션 기법으로 교육시설에 있어서 창과 운동장을 채광기준면으로 설정하여 태양의 움직임에 따른 진태양시의 일조량을 아침 8:00에서 오후 4:00까지1분 단위로 계산하였다. 또한, 아파트 신축공사 전 후의 피해에 따른 교육시설의 일조환경을 수치화하였고 일영투사법에 의해 제작된 영상과 비교하여 교육환경 일조량을 검증할 수 있었다. 향후 이러한 시뮬레이션 기법을 활용하여 교육환경일조량 분석에 효율적으로 사용될 수 있을 것으로 기대된다.

• 한국건설관리학회논문집
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• 제9권5호
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• pp.95-103
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• 2008

정부의 강력한 정책의지에 따라 무분별하게 추진되던 재건축 사업이 상당기간 침체될 것으로 예상되며 이에 대한 대안으로 공동주택 성능향상과 자산가치 보호, 거주환경 개선을 위한 리모델링의 활성화가 예상되고 있다. 그럼에도 불구하고 대다수의 주민들은 재건축에 대한 선호도가 강하며 리모델링은 최후의 수단으로만 치부하고 있다. 이러한 현실은 리모델링에 비해 재건축이 시공성 및 사업성 측면에서 유리하다는 인식이 강하게 자리잡고 있기 때문이며 재건축 추진에 대한 평가방식인 안전진단이 개발의 활성화 및 최적의 방식을 제공하기보다 획일적인 규제 위주로 이루어져 있어 이를 불신하는 현실에서 기인한다고 볼 수 있다. 따라서 공동주택 개발사업을 추진하는데 있어 가장 적합한 방식을 선택할 수 있는 합리적인 평가안을 재 정립할 필요가 있다. 이에 본 고에서는 AHP 기법을 이용하여 평가 요소간의 중요성 및 가중치를 산출하고 이를 바탕으로 개발 사례에 적용 분석하여 향후 공동주택 개발을 위한 평가 방안에 활용하고자 한다.

• 구강회복응용과학지
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• 제30권1호
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• pp.81-92
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• 2014

상악 전치부에 임플란트를 이용해 심미적으로 수복 하는 것은 많은 어려움이 따른다. 이는 치조골 흡수와 치간 유두 수축 등과 같은 임플란트 주변 경, 연조직 문제와 금속지대주 및 금속도재관의 변연노출과 낮은 광투과도 등의 보철적 한계 때문이다. 이에 본 증례에서는 경, 연조직의 증대술 및 성형술, 발치 후 즉시 식립 등과 함께 임시수복물의 장기간 사용 및 수정으로 임플란트 주위 연조직의 형태와 건강을 형성한 후, 맞춤형 인상 코핑을 사용하여 이를 최종 모형에 재현하였다. 또한 맞춤형 지르코니아 지대주와 완전 도재관을 이용해 최종 수복함으로써 기능적이고 심미적인 결과를 얻었기에 이를 보고하고자 한다.