• 한국CDE학회논문집
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• 제16권4호
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• pp.300-304
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• 2011

This paper proposes an approach to generate tool-path for laser pattern machining. Considering the mechanical structure of a laser pattern machine, it is quite similar to that of a 2D milling machine. Based on the observation, one may try to utilize the tool-path generation methodologies of 2D milling for the laser pattern machining. However, it is not possible to generate tool-path without considering the technological requirements of laser pattern machining which are different from those of 2D milling. In this paper, we identify the technological requirement of laser pattern machining, and propose a proper tool-path generation methodology to satisfy the technological requirements. For the efficient generation of tool-path, this paper proposes a tool-path element computation method, which is based on the concept of a monotone chain.

• 대한원격탐사학회지
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• 제24권3호
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• pp.223-233
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• 2008

In the mid 90's, the U.S. government released images acquired by the first generation of photo reconnaissance satellite missions between 1960 and 1972. The Declassified Intelligent Satellite Photographs (DISP) from the Corona mission are of high quality with an astounding ground resolution of about 2 m. The KH-4A panoramic camera system employed a scan angle of $70^{\circ}$ that produces film strips with a dimension of $55\;mm\;{\times}\;757\;mm$. Since GPS/INS did not exist at the time of data acquisition, the exterior orientation must be established in the traditional way by using control information and the interior orientation of the camera. Detailed information about the camera is not available, however. For reconstructing points in object space from DISP imagery to an accuracy that is comparable to high resolution (a few meters), a precise camera model is essential. This paper is concerned with the derivation of a rigorous mathematical model for the KH-4A/B panoramic camera. The proposed model is compared with generic sensor models, such as affine transformation and rational functions. The paper concludes with experimental results concerning the precision of reconstructed points in object space. The rigorous mathematical panoramic camera model for the KH-4A camera system is based on extended collinearity equations assuming that the satellite trajectory during one scan is smooth and the attitude remains unchanged. As a result, the collinearity equations express the perspective center as a function of the scan time. With the known satellite velocity this will translate into a shift along-track. Therefore, the exterior orientation contains seven parameters to be estimated. The reconstruction of object points can now be performed with the exterior orientation parameters, either by intersecting bundle rays with a known surface or by using the stereoscopic KH-4A arrangement with fore and aft cameras mounted an angle of $30^{\circ}$.

• 한국컴퓨터정보학회논문지
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• 제4권1호
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• pp.28-37
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• 1999

본 논문에서는 클록 입력을 갖는 대표적인 회로인 5비트 카운터를 대상회로로 선정하여 경계면 스캔 구조를 적용하고, 대상회로에 대한 지연시험을 위한 새로운 시험 구조와 지연시험 절차를 개발하였다. 지연시험 대상회로가 클록 입력을 갖는 경우, 기존의 경계면 스캔 구조에서는 동일한 패턴의 중복 입력, 클록 입력과 데이터 입력과의 시간 간격과, 패턴 입력과 응답값 캡쳐까지의 시간 문제에 의해 적절치 않음을 보였다. 본 논문에서 제안하는 지연 시험 구조는 클록 계수 발생기를 사용하여 연속 발생시킬 클록의 개수를 입력받아 이를 대상회로의 클록 입력에 적용하여 대상회로에 대한 입력 패턴의 중복문제를 해결하였다. 또한 시스템 클록을 TCK로 사용하여 대상회로를 정상 속도에서 동작할 수 있도록 하였다. 연속적인 클록 발생에 TCK를 사용함으로써 대상회로를 정상 속도에서 검증할 수 있다. 제안된 시험 구조와 절차는 대상회로에 대한 타이밍 시뮬레이션을 통해 동작의 정확성을 확인하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1634-1637
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• 2003

Any given object on the motor-driven turntable is pictured from 8 to 72 different views with a digital camera. 3D shape reconstruction is performed with the integrated software called by Scanware from these multiple digital photographs. There are several steps such as configuration, calibration, capturing, segmentation, shape creation, texturing and merging process during the shape reconstruction process. 3D geometry data can be exported to cad data such as Autocad input file. Also 3D image model is generated from 3D geometry and texture data, and is used to advertise the model in the internet environment. Consumers can see the object realistically from wanted views by rotating or zooming in the internet browsers with Scanbull spx plug-in. The spx format allows a compact saving of 3D objects to handle or download. There are many types of scan equipments such as laser scanners and photogrammetric scanners. Line or point scan methods by laser can generate precise 3D geometry but cannot obtain color textures in general. Reversely, 3D image modeling with photogrammetry can generate not only geometries but also textures from associated polygons. We got various 3D image models and introduced the process of getting 3D image model of an internet-connected watchdog robot.

• 한국BIM학회 논문집
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• 제10권1호
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• pp.1-8
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• 2020

In managing building facilities, spatial information is the basic data for decision making. However, the method of acquiring spatial information is not easy. In many cases, the site and drawings are often different due to changes in facilities and time after construction. In this case, the site data should be scanned to obtain spatial information. The scan data actually contains spatial information, which is a great help in making space related decisions. However, to obtain scan data, an expensive LiDAR (Light Detection and Ranging) device must be purchased, and special software for processing data obtained from the device must be available.Recently, SLAM (Simultaneous localization and mapping), an advanced map generation technology, has been spreading in the field of robotics. Using SLAM, 3D spatial information can be obtained quickly in real time without a separate matching process. This study develops and tests whether SLAM technology can be used to obtain spatial information for facility management. This draws considerations for developing a SLAM device for real-time remote scanning for facility management. However, this study focuses on the system development method that acquires spatial information necessary for facility management through SLAM technology. To this end, we develop a prototype, analyze the pros and cons, and then suggest considerations for developing a SLAM system.

• 한국염색가공학회지
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• 제35권2호
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• pp.121-127
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• 2023

In this study, a comprehensive investigation was conducted on the morphological and property changes of laser-induced nanocarbon (LINC) as a function of laser process parameters. LINC was formed on the surfaces of polyimide films with different backbone structures under various process conditions, including laser power, scan speed, and resolution. Three different forms of LINC electrodes (i.e., continuous 3D porous graphene, wooly nanocarbon fibers, line cut) were formed depending on the laser power and scan speed. Furthermore, heteroatom doping induced from the chemical structure of the polyimide during laser patterning was found to be effective in modifying the electrical properties of LINC electrodes. The LINC surfaces exhibited different microstructures depending on the laser beam resolution under constant laser power and scan speed, allowing for controllable surface wettability. The correlation between the chemical structure of the polymer substrate, laser process parameters, and carbonized surface properties in this study is expected to be utilized as fundamental understanding for the manufacturing of next-generation carbon-based electronic devices.

• 한국CDE학회논문집
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• 제10권1호
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• pp.70-75
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• 2005

A 3D solid element mesh generation algorithm was newly developed. 3D surface points of global rectangular coordinates were supplied by a 3D laser scanner. The algorithm is strait forward and simple but it generates mixed solid elements such as hexagonal, pyramid and prism types. Then, the surface triangular or rectangular elements were generated from the solid elements. The key of the algorithm is elimination of elements and 3D adaptive surface smoothing using given 3D surface point data.

• 한국항행학회논문지
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• 제13권6호
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• pp.984-990
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• 2009

하프토닝은 단색으로 다양한 계조의 색단계를 표현하는 방법으로 인쇄 매체와 같은 분야에서 제한된 색으로 다양한 톤을 표현할 수 있도록 해주는 매우 중요한 영상처리기법이다. 본 논문에서는 공간채움곡선 (Space-Filling Curve)에 의한 하프토닝 방법의 대안으로 미로 생성 알고리즘에 기반한 새로운 하프토닝 방법을 제안한다. 기존의 공간채움곡선에 의한 오류 확산방법은 규칙적인 스캔 패턴으로 인해 해프토닝의 결과에도 규칙적인 패턴이 발생한다. 이러한 부분을 개선하기 위해 공간채움곡선 대신 미로의 경로를 사용함으로써 규칙적인 패턴을 제거하였다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 1998년도 가을 학술발표논문집 Vol.25 No.2 (2)
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• pp.662-664
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• 1998

IEEE 1149.1 바운다리스캔은 보드 수준에서 고장점검 및 진단을 위한 테스트 설계기술이다. 그러나, 바운다리스캔 제어기의 특성상 테스트 패턴의 주입에서 관측까지 2.5 TCK가 소요되므로, 연결선상의 지연고장을 점검할 수 없다. 본 논문에서는 Update_DR 신호를 변경하여, 테스트 패턴 주입에서 관측까지 1 TCK가 소요되게 함으로써, 지연고장 점검을 가능하게 하는 기술을 소개한다. 나아가서, 정적인 고장점검을 위한 테스트 패턴을 개선해 지연고장 점검까지 가능하게 하는, N개의 net에 대한 2log(N+2)의 새로운 테스트패턴도 제안한다. 설계와 시뮬레이션을 통해 지연고장 점검이 가능함을 확인하였다.

• Fibers and Polymers
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• 제7권2호
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• pp.195-202
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• 2006

Tight-fitting clothing pattern reflecting the accurate information of the 3D body shape has been one of the challenges for garment industry, however, fitting problems still exist. The objectives of the paper is to develop a 2D pattern which fits tightly to the 3D human scan data for sports suits that need comfort and function for maximum performance. In this study, the user graphic interface application software for the semi-automatic garment pattern generation has been implemented using the triangle simplification scheme together with 2D projections of free-falling of 3D surface polygons keeping the original 3D surface area preservation. A typical application of the developed pattern to the functional body suits is presented and verification of the proposed method is also provided.