• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1114-1116
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• 2000

A direct model reference adaptive control (DMRAC) is applied to the speed control of brushless do(BLDC) motor. The main objective is to achieve precise speed control in the face of varying motor parameters and load. The control is described as an outer loop speed control and an inner current loop control which has raster dynamics than the speed loop. The adaptive control is applied to the outer speed control loop. DMRAC is compared to an indirect adaptive controller(IMRAC) and a PI controller. Simulation results show that the two adaptive controllers give similar respose and are superior to the PI controller. However, the DMRAC algorithm is simpler to implement.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.06a
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• pp.318-321
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• 2008

본 연구에서는 대용량의 항공 레이저 스캔 포인트 자료로부터 정규 격자 형태의 수치 표면 모델을 고속으로 생성하기 위하여 가상격자와 병렬처리를 기반으로 한 자료 처리 기법을 제안하였다. 수십$\sim$수백 평방 킬로미터 영역에 대하여 항공 레이저 스캔을 중복적으로 수행할 경우 포인트 수는 수억$\sim$수십억에 이르며 이를 일반적인 시스템에서 처리하는 데에는 한계가 존재한다. 이에 본 연구에서는 병렬처리를 위해 구성한 피씨 클러스터 상에서 자료를 분산시켜 가상격자를 이용하여 처리하는 방식을 제안하였다. 즉, 마스터 노드는 포인트 자료를 읽어 들여 포인트의 평면 좌표 값에 따라 슬래이브 노드로 전송하고 각 슬래이브 노드에서는 전송받은 포인트를 가상 격자에 저장한 후 보간(interpolation)을 수행한다. 보간 방식으로는 IDW(Inverse Distance Weightin)을 사용하였으며 제안한 방식의 효율성을 평가하기 위하여 사용된 슬래이브 노드 수에 대한 처리 시간을 측정하였다.

• Korean Journal of Computational Design and Engineering
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• v.7 no.2
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• pp.96-101
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• 2002

Rapid Prototyping (RP) technology has been advanced to fabricate initial prototypes from various materials. Stratasys′ Fused Deposition Modeling (FDM) is one of the typical RP processes that provide functional prototypes of ABS plastic. In order to predict the behavior of final ABS parts, it is critical to understand the material properties of the raw FDM process material, and the effect that FDM build parameters have on the FDM part. In this paper, we seek to characterize the properties of ABS parts fabricated by the FDM 1650. Using the Design of Experiment (DOE) approach, the process parameters of FDM, such as raster orientation, air gap, bead width, color, and model temperature were examined. Tensile strengths of crisscross specimens, 〔45°/-45°〕, cross specimens, 〔0°/90°〕, and directionally fabricated tensile specimens (〔0°〕 and 〔90°〕) were measured and compared with the injection molded FDM-ABS P400 material. For the FDM parts made with a -0.003"air gap, the typical tensile strength ranged between 50 percent and 83 percent of the strength of injection molded ABS P400. From the experiments, a couple of build rules for designing FDM parts were obtained.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1221-1223
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• 2003

With speediness of economy, the structure of land use has taken lots of change. How can we quickly and exactly obtain detailed land use/cover change information, and then we know land resource amount, quality, distributing and change direction. More and more high resolution satellite systems are under development. So we can make good use of RS data, existed GIS data and GPS data to extract change information and update map. In this paper a fully automated approach for detecting land use/cover change using remote sensing data with object-oriented classification based on GIS data, GPS data is presented (referring to Fig.1). At same time, I realize integrating raster with vector methods of updating the basic land use/land cover map based on 3S technology and this is becoming one of the most important developing direction in 3S application fields; land-use and cover change fields over the world. It has been successful applied in two tasks of The Ministry of Land and Resources P.R.C and taken some of benefit.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.923-926
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• 2003

In this paper we propose a scheme to generate DTM and detect buildings on DSM generated from LIDAR data. Two stages are performed. The first stage is to perform object segmentation by using two morphology operations namely, flattening and H-Dome transformation. After filtering out the object points above the ground, we used the non-object points to generate DTM. The second stage is to detect buildings from the objects by analyzing differential slopes. The test data is in raster form with 1m spacing around Hsin-Chu Scientific Area in Taiwan. The mean error is -0.16m and the RMSE is 0.45m for DTM generation. The successful rate for building detection is 87.7%.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.269-273
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• 2003

In the rice planted acreage estimation, high precise measurement and laborsaving are required by using satellite data. A method referring accurate agricultural plot vector data was used in this paper which improves the estimation accuracy of rice planted acreage compared with conventional methods. In this method, satellite data are not used for totalization, although they are used to discriminate whether the fields are rice planted or not. This paper described the result of the above method using to ASTER-VNIR data.

• Korean Journal of Remote Sensing
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• v.12 no.1
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• pp.17-25
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• 1996

This paper presents a GCP marking technique using scanned maps. Twelve maps with a scale of 1:250, 000 were scanned and stored as raster images. The distortion factors of scanned maps were modelled by polynomials. The coefficients of the polynomials were determined by a least squre fit. This technique does not require a bulky and expensive digitizing table so that it is suitable for a low-cost pre-processing system. The GCP marking using this technique showed a sufficient accuracy for KITSAT1, 2 narrow camera images.

• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.789-792
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• 2010

최근 다양하게 활용되고 있는 수치지도 기반의 지도 영상은 그 신속성과 정확성이 가장 중요시되고 있다. 특히, 공군에서 사용하고 있는 지도영상 자료 활용 시스템인 비행 임무 계획 시스템의 상황도 시현 시, 대용량 래스터 데이터(Raster Data)를 처리해야 하는데, 지도의 종류가 다양해지고, 정밀해질수록 시스템의 효율적인 구동에 한계가 발생되고 있는 현실이며, 처리하는 영상의 호환성 및 왜곡현상의 문제점도 함께 야기되고 있다. 이에 본 연구에서는 ARC System 및 RPF Naming Rule을 적용하여 대용량 래스터 데이터 처리과정을 개선하고, 호환성을 보장하며, 왜곡현상을 줄이는 효율적인 지도 영상 처리방안을 제안한다.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1134-1139
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• 2009

Haul routes for earthmoving operation need to be carefully selected because the decision on the haul routes could make a significant difference in the project's cost and time. This paper proposes a decision support system for improving productivity of earthmoving operation that helps construction managers choose the best haul routes of trucks based on time slots. Also, a methodology for optimal selection of haul routes considering traffic conditions and topographic conditions of the routes is explained. Raster data model is used to find an available shortest path based on cost weighted distance. A system was developed on a geographic information system environment for efficient database management and easy manipulation of graphical data. A real-world case study was conducted to verify the applicability of the proposed system.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.42.1-42.1
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• 2019

We investigate a collapsing granule event and the associated excitation of waves in the photosphere and chromosphere. Our observations were carried out by using the Fast Imaging Solar Spectrograph and the TiO 7057Å Broadband Filter Imager of the 1.6 meter Goode Solar Telescope of Big Bear Solar Observatory. During our observations, we found a granule which became significantly darker than neighboring granules. The edge of the granule collapsed within several minutes. After the collapse, transient oscillations occurred in the photospheric and chromospheric layers. The dominant period of the oscillations is close to 4.5 minutes in the photosphere and 4 minutes in the chromosphere. Moreover, in the Ca II-0.5Å raster image, we observed brightenings which are considered as the manifestation of shock waves. Based on our results, we suggest that the impulsive collapse of a granule can generate upward-propagating acoustic waves in the solar quiet region that ultimately develop into shocks.