• Spatial Information Research
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• 제11권4호
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• pp.421-437
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• 2003

전산화된 지적도를 그대로 사용하여 필지경계점 위치, 필지면적, 필지경계선의 길이를 계산하고, 법적으로 유효한 도면으로 사용하기 위해서는 왜곡을 보정하여야 한다. 왜곡보정방법으로서 4 도곽점을 이용한 2차원부등각변환법, 지적도를 9개의 영역으로 분할하는 방법, 세부측량원도를 이용하는 방법, 도곽선을 직선화하면서 보정하는 방법들이 연구되었다. 본 연구에서는 이 네가지 보정방법을 지적도에 적용하여 필지경계점의 위치 보정을 하고, 그 보정의 정확도를 비교 분석하였다. 불규칙적으로 일어난변형을 완전하게 보정할 수는 없으나, 4 도곽점을 이용하여 2차원투영변환으로 보정한 후 도곽선 직선화에 의한 보정을 추가하는 것이 왜곡을 최소화할 수 있는 방안으로 판단되었다.

• 한국환경과학회지
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• 제15권11호
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• pp.1077-1086
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• 2006

This study aims at analyzing relationships between land use and habitat types of winter wildbirds to provide basic understanding of ecosystem for preservation and restoration of urban ecosystem in the future. The research area is Hanam City. Researches on land use types showed Hanam City had 79.1% of greenspace and openspace, but intensive urban development has been taking place in greenspace that is adjacent to urban districts. This has brought the problems of lack of greenspace in urban districts and damages to cultivated areas and grassland. A total of 61 and 8,642 populations of winter wildbird species were observed in research areas. Paradoxornis webbiann(16.91), Passer montanus(11.93), Pica pica(6.88) were dominant species. When they were divided according to habitat types, 20 species of interior species, 8 species of interior-edge generalist species, 12 species of edge species and 3 species of urban species were observed. When which land use type was mostly served as wildbirds habitats was examined, urban species(3 species and 290 populations) was a dominant species in urban districts while in greenspace and openspaece, water species(19species and 3,075 populations) including winter migratory birds was. Among greenspace and openspaece, edge species was dominant in forest while urban species was a dominant species in cultivated areas. This shows there is a need to improve diversity of wildbirds through restoration of cultivated areas in the central part of Hanam City.

• 전기전자학회논문지
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• 제11권4호
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• pp.235-238
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• 2007

2차원 소자 시뮬레이터인 TMA 메디치를 이용하여 필드링와 깊은 접합 필드링에 대해 연구하였다. 이온 주입될 위치를 미리 트랜치 식각을 시킴으로써 항복전압 특성을 향상시킬 수 있었다. 시뮬레이션 결과 기존 필드링의 항복전압대비 깊은 접합 필드링 항복전압은 약 30%의 증가를 보였다. 깊은 접합 필드링은 같은 면적을 차지하는 조건하에서 설계 및 제작이 비교적 용이하고, 표면 전하의 영향도 적은 것으로 나타났다. 본 논문에서는 여러 분석을 통해 깊은 접합 필드링의 향상된 특성을 논하였다.

• Journal of Welding and Joining
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• 제21권5호
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• pp.525-533
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• 2003

The dimensional accuracy and global roughness between successive layers of VLM-s, which is a new rapid prototyping process using hotwire cutter and EPS foam, depend significantly on the operating parameters of hotwire cutter. In the present study, the effect of cutting angle on the kerf width and edge shape in hotwire cutting of EPS foam for the case of single-sloped cutting with one cutting angle was investigated. Through single-sloped cutting tests, the modified relationship between kerf width and effective heat input, considering the effect of the cutting angle, and the relationship between the melted area and the cutting angle were obtained. In order to investigate the effect of cutting angles on the thermal field in EPS foam, transient heat transfer analyses using single-sloped volumetric heat flux model and locally-conformed mesh were performed. Through the comparison between experimental and numerical results, it was shown that the proposed analysis model is needed to estimate the three-dimensional temperature distribution of the EPS foam for the case of single-sloped hotwire cutting.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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• pp.171-171
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• 1999

We studied the charge redistribution in the Pt-M (M=Cu, Co) alloys by X-ray Absorption Near Edge Spectroscopy(XANES) and X-ray Photoelectron Spectroscopy(XPS). These analysis tools provide us information about the charge transfer in the valence band of intermetallic bonding. The samples were prepared by arc-melting method. After annealing this samples in vacuum for several hours, we cold get the ordered samples, which were confirmed with XRD analysis. the core and valence level energy shift in these system were investigated by Mg $K\alpha$(1253.6eV) x-ray source for Pt-Co alloys and monochromatized Al $K\alpha$ (1486.6eV) for Pt-Cu alloys. Pt L2, L3-edge, and Cu, Co K-edge XANES spectra were measured with the total electron-yield mode detector at the 3Cl beam line of the PLS (Pohang light source0. from the changes of White line (WL) area and the core level shifts of the each metal sites, we can obtain the information about the electrons participating in the intermetallic bonding of the Pt-Cu and Pt-Co alloys.

• 제어로봇시스템학회논문지
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• 제14권1호
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• pp.54-61
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• 2008

This paper proposes a new algorithm for detecting and recognizing overlapped objects among a stack of arbitrarily located objects using a signature representation scheme. The proposed algorithm consists of two processes of detecting overlap of objects and of determining the boundary between overlapping objects. To determine overlap of objects, in the first step, the edge image of object region is extracted and those areas in the object region are considered as the object areas if an area is surrounded by a closed edge. For each object, its signature image is constructed by measuring the distances of those edge points from the center of the object, along the angle axis, which are located at every angle with reference to the center of the object. When an object is not overlapped, its features which consist of the positions and angles of outstanding points in the signature are searched in the database to find its corresponding model. When an object is overlapped, its features are partially matched with those object models among which the best matching model is selected as the corresponding model. The boundary among the overlapping objects is determined by projecting the signature to the original image. The performance of the proposed algorithm has been tested with the task of picking the top or non-overlapped object from a stack of arbitrarily located objects. In the experiment, a recognition rate of 98% has been achieved.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1798-1803
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• 2003

Surface and edge finishing processes are important technological operations of in parts machining. Quality of the finished parts directly affect the performance of the whole product. Especially, edge quality, which depends on burr control, is extremely important. Burrs are undesirable projections of the material beyond the edge of the workpiece. A number of deburring processes have been developed such as barreling, brushing, chemical methods etc. But, there are only few publications in the area of applying ultrasonics to deburring. When ultrasonic vibration propagates in the liquid medium, a large number of bubbles are formed. These bubbles generate an extremely strong force, which can be used to remove burrs. Cavitation is used as a term to describe the erosion of parts caused by the action of cavities in liquid. The object of this study is to analyze the effects of ultrasonic cavitation in the deburring process. For this purpose, we introduce a new ultrasonic cavitation method, which efficiently removes the burrs. Experimental parameters to verify the deburring effects of ultrasonic cavitations are ultrasonic power, amplitude, distant of the transducer from the workpiece, deburring time and abrasive. It has been shown that deburring with ultrasonic cavitation in water is effective to burrs.

• 반도체디스플레이기술학회지
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• 제11권2호
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• pp.1-6
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• 2012

In this study, a high performance rotary magnet type magnetron source for roll-to-roll sputter system has been developed. We analyzed the density of magnetic field as a function of size variation of the magnet which are in the center and edge of the target. The target efficiency showed the best result when the width of center magnet, the width of edge magnet, the angle of edge magnet, and the rotation angle of Yoke are 20mm, 10mm, $56^{\circ}$, and $16^{\circ}$, respectively. On the basis of the results of magnet array, Roll-to Roll magnetron source was fabricated and tested. The uniformity of the film thickness and that of the sheet resistance was ${\pm}1.62%$ and ${\pm}4.13%$, and the resistivity was $2.79{\times}10^{-3}W{\cdot}cm$.

• Journal of information and communication convergence engineering
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• 제11권2호
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• pp.124-131
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• 2013

Extraction and representation of postures and/or gestures from human activities in videos have been a focus of research in this area of action recognition. With various applications cropping up from different fields, this paper seeks to improve the performance of these action recognition machines by proposing a shape-based silhouette-edge descriptor for the human body. Information entropy, a method to measure the randomness of a sequence of symbols, is used to aid the selection of vital key postures from video frames. Morphological operations are applied to extract and stack edges to uniquely represent different actions shape-wise. To classify an action from a new input video, a Hausdorff distance measure is applied between the gallery representations and the query images formed from the proposed procedure. The method is tested on known public databases for its validation. An effective method of human action annotation and description has been effectively achieved.

• Journal of Mechanical Science and Technology
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• 제19권12호
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• pp.2312-2320
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• 2005

The aerodynamic effects of leading-edge accretion can raise important safety concerns since the formulation of ice causes severe degradation in aerodynamic performance as compared with the clean airfoil. The objective of this study is to develop a numerical simulation strategy for predicting the particle trajectory around an MS-0317 airfoil in the test section of the NASA Glenn Icing Research Tunnel and to investigate the impingement characteristics of droplets on the airfoil surface. In particular, predictions of the mean velocity and turbulence diffusion using turbulent flow solver and Continuous Random Walk method were desired throughout this flow domain in order to investigate droplet dispersion. The collection efficiency distributions over the airfoil surface in simulations with different numbers of droplets, various integration time-steps and particle sizes were compared with experimental data. The large droplet impingement data indicated the trends in impingement characteristics with respect to particle size ; the maximum collection efficiency located at the upper surface near the leading edge, and the maximum value and total collection efficiency were increased as the particle size was increased. The extent of the area impinged on by particles also increased with the increment of the particle size, which is similar as compared with experimental data.