• Journal of International Society for Simulation Surgery
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• 제1권1호
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• pp.37-40
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• 2014

Purpose For living donor liver transplantation, liver segmentation is difficult due to the variability of its shape across patients and similarity of the density of neighbor organs such as heart, stomach, kidney, and spleen. In this paper, we propose an automatic segmentation of the liver using multi-planar anatomy and deformable surface model in portal phase of abdominal contrast-enhanced CT images. Method Our method is composed of four main steps. First, the optimal liver volume is extracted by positional information of pelvis and rib and by separating lungs and heart from CT images. Second, anisotropic diffusing filtering and adaptive thresholding are used to segment the initial liver volume. Third, morphological opening and connected component labeling are applied to multiple planes for removing neighbor organs. Finally, deformable surface model and probability summation map are performed to refine a posterior liver surface and missing left robe in previous step. Results All experimental datasets were acquired on ten living donors using a SIEMENS CT system. Each image had a matrix size of $512{\times}512$ pixels with in-plane resolutions ranging from 0.54 to 0.70 mm. The slice spacing was 2.0 mm and the number of images per scan ranged from 136 to 229. For accuracy evaluation, the average symmetric surface distance (ASD) and the volume overlap error (VE) between automatic segmentation and manual segmentation by two radiologists are calculated. The ASD was $0.26{\pm}0.12mm$ for manual1 versus automatic and $0.24{\pm}0.09mm$ for manual2 versus automatic while that of inter-radiologists was $0.23{\pm}0.05mm$. The VE was $0.86{\pm}0.45%$ for manual1 versus automatic and $0.73{\pm}0.33%$ for manaual2 versus automatic while that of inter-radiologist was $0.76{\pm}0.21%$. Conclusion Our method can be used for the liver volumetry for the pre-surgery planning of living donor liver transplantation.

• 한국항공우주학회지
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• 제30권1호
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• pp.147-154
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• 2002

발사체의 발사 시험과 운용에 있어, 예기치 못한 로켓의 오작동으로 인한 인명과 재산의 피해를 예방 또는 최소화하기 위하여 비행안전 시스템은 매우 중요한 역할을 한다. KSR-Ⅲ 발사시 처음으로 운용될 비행안전 시스템은 비행안전 디스플레이 시스템과 비행종단 시스템으로 나뉘어진다. 발사 후 비행중인 로켓의 여러 비행상태와 예상낙하점등은 실시간으로 디스플레이 시스템을 통하여 관찰되며, 로켓이 안전영역을 벗어나거나 로켓의 추적이 불가능하게 될 경우 비행종단시스템은 로켓의 비행을 즉시 중단시키는 역할을 한다. 본 논문에서는 비행안전 시스템 구현에 관하여 수행된 실시간 비행안전 디스플레이 시스템과 비행종단시스템의 개발에 관하여 기술하고 있다.

• 제어로봇시스템학회논문지
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• 제21권8호
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• pp.788-793
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• 2015

This paper proposes a path planning algorithm to reduce the inspection time of AOI (Automatic Optical Inspection) machines for SMT (Surface Mount Technology) in-line system. Since the field-of-view of the camera attached at the machine is much less than the entire inspection region of board, the inspection region should be clustered to many groups. The image acquisition time depends on the number of groups, and camera moving time depends on the sequence of visiting the groups. The acquired image is processed while the camera moves to the next position, but it may be delayed if the group includes many components to be inspected. The inspection delay has influence on the overall job time of the machine. In this paper, we newly considers the inspection delay time for path planning of the inspection machine. The unified approach using genetic algorithm is applied to generates the groups and visiting sequence simultaneously. The chromosome, crossover operator, and mutation operator is proposed to develop the genetic algorithm. The experimental results are presented to verify the usefulness of the proposed method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.887-891
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• 1992

In this study, it is developed the interactive DNC(Direct Numerical Control) system, in using RS-232C cable and auxiliary computer, through the diagnosis of planning process and information evaluation. this DNC system recognize the Manufacturing planning and control it. This DNC system has a different notation. It can be done by an operator who hasn't knowledge about personnel computer. It is operated with automatic planning and measurement tec. by operator, using part program on the NC(Numerical Control).

• 지능정보연구
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• 제8권2호
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• pp.71-89
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• 2002

본 논문에서는 컨테이너 터미널의 운영 계획들을 통합된 환경에서 수립할 수 있도록 지원하는 시스템 개발 사례를 소개한다. 과거 터미널 운영 계획이 선석, 장치장, 선적계획 등 단위 계획별로 계획 시스템이 따로 개발되었던 점을 보완하여 각 계획간의 연계 작업 및 재조작이 가능할 수 있도록 하나의 통합된 시스템으로 설계하고 구현하였다. 개발된 시스템은 통합 운영 계획 작성, 사용자 편의성을 고려한 Interface, 규칙에 의한 자동 계획 및 오류에 대한 경고, 계획 수정의 용이성 등을 특징으로 하고 있다.

• 대한산업공학회지
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• 제21권1호
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• pp.51-65
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• 1995

This paper presents an automatic fixture planning system for machining processes of prismatic parts. A rationalized approach to integrate fixture planning with process planning is proposed and representation schemes for workpiece, part design information with features, machine tools, cutting tools and fixtures are developed. The proposed system implements two activities of fixture planning such as machining of reference surfaces and machining of features. For machining of reference surfaces, the machining sequence of reference surfaces is determined by using decision tables, which are drawn from relations of part dimension, degree of surface roughness, fixture type and its capacity, cutting tool's capacity and experienced planners' knowledge. For machining of features, a preferential machining orientation is selected for its feature which can be machined in more than one direction, and features with the same machining orientation are grouped, and the machining sequence of features is determined by interactive mode. A case study is performed to show the performance of the proposed system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.164-166
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• 2006

Wien Automatic System Planning Package (WASP) which is used to draw out generation expansion planning applies Dynamic Programming in Korea power system panning. While this package has an advantage that computes annual capacity, it has a disadvantage that can't consider environmental constraints. With the effectuation of the Kyoto Protocol in February, 2005, it is expected that CO2 emission has a severe effect on Korean power system. Therefore, as the most important issue, the generation expansion planning considering environmental constraints is rising in power system. This paper develops a mathematic model including not only generation expansion planning but transmission planning and considering regional supply-demand and environmental constraints, especially CO2 emission, and verifies propriety through the case study.

• 한국농공학회지
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• 제44권6호
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• pp.71-82
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• 2002

The purpose of this study is to develop a 3 dimensional spatial planning model (3DSPLAM) for facilities allocation and visual evaluation in improvement planning of rural village. For the model development, this study developed both planning layers and a modelling process for spatial planning of rural villages. The 3DSPLAM generates road networks and village facilities location automatically from built area plan map and digital elevation model generated by geographic information system. The model also simulates 3-dimensional villagescape for visual presentation of the planned results. The 3DSPLAM could be conveniently used for automatic allocation of roads, easy partition of land lots and reasonable locating of facilities. The planned results could be also presented in the stereoscopic models with varied viewing positions and angles.

• 한국정밀공학회지
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• 제13권3호
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• pp.158-164
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• 1996

In this paper, the CNC cutting planning module for product with three dimensional solid shape is realized to develop a smart CAD/CAM system which performs systematically from the shape design of procuct by the B-Rep solid modeler to the CNC cutting of product by a machining center. The three dimensional solid shape of product can be easily designed and constructed by the Euler operators and Boolean operators of the solid modeler. And the various functions such as the automatic generation of tool path for the rough and finish cutting processes, the automatic elimination of overcut, the automatic generation of CNC code for the machining center and do on, are established. Especially, the overcut-free tool paths are obtained by splitting the CL solid which is composed of the offset surfaces of the solid shape of product.

• 농촌계획
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• 제18권2호
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• pp.39-45
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• 2012

The objective of this study was to analyze the determinant factors in the new agricultural technology acceptance targeted to the automatic switchgear for heat-retaining mulching used on the oriental melons farms. The probit and the logit models were estimated using survey data. The result indicated that the level of income, innovativeness, and reliability are important factors of the new agricultural technology acceptance. Therefore, it is considered the level of income, innovativeness, and reliability in advance to extend the new agricultural technology quickly.