• Title/Summary/Keyword: Block adjustment

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Exterior Orientation Parameters Determination from Satellite Imagery RPC Camera Model (위성영상 RPC 카메라 모델로부터 외부표정요소 결정)

  • Lee Hyo Sung
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.23 no.1
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    • pp.59-67
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    • 2005
  • This paper proposes method for determining exterior orientation parameters (EOPs) from the RPC mathematical camera model of the satellite image. SPOT satellite stereo pair is pre-tested using the proposed method. As results that, geopositioning errors are similar with those of the original EOPs. Differences between EOPs determined from the RPC and original EOPs were small. IKONOS Geo-level stereo pair is tested by the proposed method. Results of this method are compared with those of the RPC block adjustment method which have been verified in reported studies. Consequently, the proposed method showed accuracy similar to the RPC block adjustment method. The digital elevation models (DEMs) of sample area acquired by the two method almost did not have a difference.

Exterior Orientation Parameters Determination of Aerial Photogrammetry by GPS Code Phases Measurement (GPS 코드파 관측에 의한 항공삼각측량의 외부표정요소의 결정)

  • 박운용;이동락;신상철
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.15 no.2
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    • pp.157-164
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    • 1997
  • This study deals with GPS-photogrammetry practicability by C/A-code reception. It allows data to be acquired and analyzed fast. Combined block adjustment method was applied at the topographical map production of coast-land. And we compared it that of conventional block adjustment. As a result, it was found that accuracy was very sensitive to the arrangement and number of control points. The accuracy in the horizontal and vertical was $\pm{2cm}$ if all of the control points was available. however accuracy was not affected at additional parameters for systematic errors' elimination and it leads to bad results when the number of control points was few and arrangement of control points was not stabilized. GPS observations were added in block adjustment, but the accuracy of block was not upgraded due to the low accuracy of C/A-code reception. So relative positioning method with carrier phases was required for high accuracy and it is expected that CPS photogrammetry with C/A-code will be used widely according to the improvement of observation methods and the development of receiver.

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PoW-BC: A PoW Consensus Protocol Based on Block Compression

  • Yu, Bin;Li, Xiaofeng;Zhao, He
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.4
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    • pp.1389-1408
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    • 2021
  • Proof-of-Work (PoW) is the first and still most common consensus protocol in blockchain. But it is costly and energy intensive, aiming at addressing these problems, we propose a consensus algorithm named Proof-of-Work-and-Block-Compression (PoW-BC). PoW-BC is an improvement of PoW to compress blocks and adjust consensus parameters. The algorithm is designed to encourage the reduction of block size, which improves transmission efficiency and reduces disk space for storing blocks. The transaction optimization model and block compression model are proposed to compress block data with a smaller compression ratio and less compression/ decompression duration. Block compression ratio is used to adjust mining difficulty and transaction count of PoW-BC consensus protocol according to the consensus parameters adjustment model. Through experiment and analysis, it shows that PoW-BC improves transaction throughput, and reduces block interval and energy consumption.

Adjustment of Exterior Orientation Parameters Geometric Registration of Aerial Images and LIDAR Data (항공영상과 라이다데이터의 기하학적 정합을 위한 외부표정요소의 조정)

  • Hong, Ju-Seok;Lee, Im-Pyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.5
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    • pp.585-597
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    • 2009
  • This research aims to develop a registration method to remove the geometric inconsistency between aerial images and LIDAR data acquired from an airborne multi-sensor system. The proposed method mainly includes registration primitives extraction, correspondence establishment, and EOP(Exterior Orientation Parameters) adjustment. As the registration primitives, we extracts planar patches and intersection edges from the LIDAR data and object points and linking edges from the aerial images. The extracted primitives are then categorized into horizontal and vertical ones; and their correspondences are established. These correspondent pairs are incorporated as stochastic constraints into the bundle block adjustment, which finally precisely adjusts the exterior orientation parameters of the images. According to the experimental results from the application of the proposed method to real data, we found that the attitude parameters of EOPs were meaningfully adjusted and the geometric inconsistency of the primitives used for the adjustment is reduced from 2 m to 2 cm before and after the registration. Hence, the results of this research can contribute to data fusion for the high quality 3D spatial information.

Process Improvement in Feedback Adjustment

  • Lee, Jae-June;Kim, Yong-Hee
    • Communications for Statistical Applications and Methods
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    • v.19 no.3
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    • pp.395-403
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    • 2012
  • Process adjustment, also called engineering process control(EPC), is applied to maintain process output close to a target value by manipulating controllable variables, but special causes may still make the process deviate from the target and result in significant costs. Thus, it is important to detect and mediate deviations as early as possible. We propose a one-step detection method, the moving search block(MSB), with which the time and type of a special cause can be identified in short periods. A modified control rule that can entertain the effects of the special cause is proposed. A numerical example is presented to evaluate the performance of the proposed scheme.

Application of Sensor Technology for the Efficient Positioningand Assembling of Ship Blocks

  • Lee, Sang-Don;Eun, Seong-Bae;Jung, Jai-Jin;Song, Ha-Cheol
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.2 no.3
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    • pp.171-176
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    • 2010
  • This paper proposes the application of sensor technology to assemble ship blocks efficiently. A sensor-based monitoring system is designed and implemented to improve shipbuilding productivity by reducing the labor cost for the adjustment of adequate positioning between ship blocks during pre-erection or erection stage. For the real-time remote monitoring of relative distances between two ship blocks, sensor nodes are applied to measure the distances between corresponding target points on the blocks. Highly precise positioning data can be transferred to a monitoring server via wireless network, and analyzed to support the decision making which needs to determine the next construction process; further adjustment or seam welding between the ship blocks. The developed system is expected to put to practical use, and increase the productivity during ship blocks assembly.

Design of a Multiband Frequency Selective Surface

  • Kim, Dong-Ho;Choi, Jae-Ick
    • ETRI Journal
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    • v.28 no.4
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    • pp.506-508
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    • 2006
  • A frequency selective surface (FSS), whose unit cell consists of a ternary tree loop loaded with a modified tripole, is proposed to block multiple frequency bands. Target frequency bands correspond to Korean personal communication services, cellular mobile communication, and 2.4 GHz industrial, scientific, and medical bands. Through the adjustment of inter-element and inter-unit cell gaps, and adjustment of the length of elements, we present an FSS design method that makes the precise tuning of multiple resonance frequencies possible. Additionally, to verify the validity of our approach, simulation results obtained from a commercial software tool and experimental data are also presented.

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Accuracy Analysis of Combined Block Adjustment with GPS/INS Observations Considering Photo Scale (사진축적을 고려한 GPS/INS 항공사진측량 블록조정의 정확도 분석)

  • Lee Jae One
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.23 no.3
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    • pp.323-330
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    • 2005
  • More than ten years after the era of GPS-Photogrammetry which could provide us only three projection center of all six exterior orientation parameters, direct georeferencing with GPS/INS is now becoming a standard method for image orientation. Its main advantage is to skip or reduce the indirect ground control process. This paper describes the experimental test results of integrated sensor orientation with a commercial GPS/IMU system to approve its performance in determination of exterior orientation. For this purpose two different imaging blocks were planned and the area was photographed at a large photo scale of 1:5,000 and a medium photo scale of 1:20,000. From these data set a variety of meaningful results was acquired, i.e., the accuracy. potential of exterior orientation from direct georeferencing and combined block adjustment using these data considering different photo scales and conditions.

A Development of a Casual Pants Block Pattern for 7 Years Old Boy (7세 남아 캐주얼 바지 패턴 개발)

  • Lee, Eun-Hye;Jung, Jin-A;Jo, Jin-Sook
    • Journal of the Korean Society of Clothing and Textiles
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    • v.33 no.1
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    • pp.11-21
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    • 2009
  • It is remarkable that the children's wear market has been growing instead of declining birth rate. The parents are willing to pay more when they find children's wear of better design and improved quality. For better quality, it is necessary to research on the pattern making of children's wear. After the interview with the 10 leading children's brands, we found that they develop individual design pattern based on each items middle block pattern which characterize the brands design line. Most frequently used middle block is for casual pants. Through interview with pattern designers, comparative study of patterns drafting methods, wearing test of trial garments and altering and adjustment of patterns, we developed the casual pants block pattern for 7 years old boys.