• Title/Summary/Keyword: Scale height

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Evaluation on Tie Point Extraction Methods of WorldView-2 Stereo Images to Analyze Height Information of Buildings (건물의 높이 정보 분석을 위한 WorldView-2 스테레오 영상의 정합점 추출방법 평가)

  • Yeji, Kim;Yongil, Kim
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.5
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    • pp.407-414
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    • 2015
  • Interest points are generally located at the pixels where height changes occur. So, interest points can be the significant pixels for DSM generation, and these have the important role to generate accurate and reliable matching results. Manual operation is widely used to extract the interest points and to match stereo satellite images using these for generating height information, but it causes economic and time consuming problems. Thus, a tie point extraction method using Harris-affine technique and SIFT(Scale Invariant Feature Transform) descriptors was suggested to analyze height information of buildings in this study. Interest points on buildings were extracted by Harris-affine technique, and tie points were collected efficiently by SIFT descriptors, which is invariant for scale. Searching window for each interest points was used, and direction of tie points pairs were considered for more efficient tie point extraction method. Tie point pairs estimated by proposed method was used to analyze height information of buildings. The result had RMSE values less than 2m comparing to the height information estimated by manual method.

Large-Scale Vertical Structure in Separated and Reattaching Turbulent flow over a Backward Facing Step (후향계단 난류 박리재부착 유동에서의 대형와의 구조)

  • Ahn, Seung-Kwang;Lee, In-Won;Sung, Hyung-Jin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.12
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    • pp.1674-1680
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    • 2002
  • An experimental study was made of a large-scale vortical structure over a backward-facing step. The Reynolds number based on the step height was R $e_{H}$ =33,000. To recognize the large-scale vortex, three components of velocity were measured. The measurements were performed in the recirculation zone (x/H=4.0) and the reattachment zone(x/H=7.5). To measure the wall pressure fluctuations in a turbulent flow over a backward-facing step, a 32-channel microphone array was installed beneath the wall in the streamwise and spanwise directions. From the measured pressure field, the size of large-scale vortex was obtained. As a detailed study, a conditionally-averaging technique was employed to characterize the coherent structure of the large-scale vortex. To see the relationship between the flow field and the relevant spatial mode of the pressure field, the spatial box filtering (SBF) was examined. A cross-correlation between velocity and pressure fluctuations was performed to identify the structure and the length scale of the large-scale vortex.x.

Development of a Capacitance-type wave Recorder for Measuring Real-Time Wave Height Based on Microprocessor Technique (마이크로프로세서 기술에 기초한 실시간 파고 계측용 용량식 파고계의 개발)

  • 김제윤;김환성;김상봉
    • Journal of Ocean Engineering and Technology
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    • v.10 no.3
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    • pp.162-167
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    • 1996
  • This paper deals with an implementation method for the one chip microprocessor(8097)-based capacitance type wave recorder for a measuring real-time wave height. The system was developed to make it possible to real-time remote sensing the wave height by deploying the RS-232/422/485 communication methods. The system test results for the developed system such as linearity, system stability and robustness of the disturbance was also verified through the performance tests of the system. Furthermore, the system was developed after due consideration with connecting the public network such as satellite mobile communication system and LAN, through the deploying VLSI(Very Large Scale Integration) design techniques.

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Indented Surface Configuration and its Volume Calculation (압입 표면형상의 구현과 체적계산법)

  • Yang, Jae-Yong;Yoon, Moon-Chul
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.5
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    • pp.708-713
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    • 2012
  • The indented geometry for rockwell hardness indenter has been configured by using Confocal Laser Scanning Microscopy (CLSM). For this purpose, the CLSM can be well suited to construct the three-dimensional indented volume from the indented surface by rockwell hardness tester. Furthermore, the height data of HEI(height encoded image) by CLSM must be acquired at first and converted to indented surface later. And the indented surface patterns enable us to predict the indenter shape and volume. This volume can be used to study the rockwell hardness model as a volume parameter. As a result, the technique performed in this study by combining the CLSM with compensation technique is an excellent one to obtain the geometries of indented surfaces over a wide range of surface resolution in a micro scale. And it can be used for micro volume calculation.

a biologically inspired small-scale water jumping robot (작은 스케일의 생체 모방 수상 점프 로봇)

  • Shin, Bong-Su;Kim, Ho-Young;Cho, Kyu-Jin
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1427-1432
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    • 2008
  • This paper describes the locomotion of a water jumping robot which attempts to emulate the fishing spider’s ability to jump on the water surface. While previous studies of the robots mimicking arthropods living on water were focused on recreating their horizontal skating motions, here we aim to achieve a vertical jumping motion. The robot jumps by pushing the water surface with rapidly released legs which were initially bent. The motion is triggered with a latch driven by the shape memory alloy actuator. The robot is capable of jumping to the maximum height of 26mm. Jumping efficiency, defined the maximum jumping height on water over the maximum jumping height on rigid ground, is 0.26 This work represents a first step toward robots that can locomote on water with superior versatility including skating and jumping.

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A Study on the Daylight Distribution Analysis in different Height of Roller Shade in a Small Office (Roller Shade 높이 조절에 따른 사무소 건축물의 주광유입분포 분석에 관한 연구)

  • Lim, Ji-Sun;Kim, Yu-Sin;Choi, An-Seop
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2008.10a
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    • pp.17-20
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    • 2008
  • Available daylight in inside offers comfortable view environment, and psychological and physical advantages to people in the room. But, it has a problem of an excessive direct sunlight. This study analyzed daylight distribution characteristic by roller shade systems with a Mock-up test. With three 1/2 Scale Mock-up rooms, we performed a test of daylight distribution performance in different shade height of each room through the different height of roller shade. systems. This research will be used as a fundamental study for automated roller shade systems.

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The Optimum Design of Flow Characteristics in Fermentation (발효조 내의 유동특성 최적화 설계)

  • 박상규;김기성;양희천
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2001.05a
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    • pp.117-121
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    • 2001
  • A numerical simulation was conducted to investigate the effect of height position of Rushton type Impeller in the fermentation. The computational method was based on the CFX code. The simulation was performed for 3 height differences(25, 30, 35mm) between Rushton type impeller and bottom of fermentation. The instantaneous flow fields showed that the bulk flow consisted of large scale vortices. However the main flow results showed that the formation of ring vortices above and below the impeller depended on the height of the impeller.

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Analyzing lateral strength and failure modes in masonry infill frames: A mesoscale study

  • Sina GanjiMorad;Ali Permanoon;Maysam Azadi
    • Earthquakes and Structures
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    • v.27 no.2
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    • pp.113-126
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    • 2024
  • In this study, the failure mechanisms of masonry-infilled frames, commonly employed in modern construction, are analyzed at the mesoscale. An equation has been formulated to predict various failure modes of masonry-infilled frames by examining 1392 frames. The equation takes into account variables such as the height-to-width ratio, compressive strength of the masonry prism, and plastic moment capacity of the frame section. The study reveals that the compressive strength of the masonry prism and the height-to-width ratio exert the most significant influence on the lateral strength of masonry-infilled frames with a height-to-width ratio ranging from 0.2 to 1.2. The developed equation demonstrates substantial agreement with previously reported relationships, indicating high accuracy. These findings provide valuable insights into the lateral strength of infill masonry frames, which can contribute to their improved evaluation and design.

Scale Model Testing of a two-boat midwater trawl net (2척식 중층트롤 모형실험)

  • Jang, Ji-Won;Kim, Chun-Duk;Kim, Tae-An
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.5 no.1
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    • pp.14-20
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    • 1969
  • A scale model net test of the operation of a small two-boat midwater trawl net was performed in the circulating water tank at Pusan Fisheries College. The 1/32 scale model net was constructed after the modelling law of M. Tauti. This type of net is used in Europe for catching sprat like Hering. The net used was 1/32 the actual size. This scale was chosen with consideration for the water tank size. In this experiment, the transfomation of the net shape was observed especially inregard to variations in the height and breadth of the net mouth. These dimensions were varied by changing the breadth of the towing line and the connenting spread.

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Evaluation of Strength Parameters of North-Cheju Basalt Rubble Using Large-Scale Triaxial Test (대형삼축압축시험을 이용한 북제주현무암 사석재의 강도정수 산정)

  • 정철민;김종수;채영수
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.189-196
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    • 2002
  • According to the Korean Design Code for port and harbor facilaties, bearing capacity of rubble mound under eccentric and inclined load is calculated by the simplified Bishop method, and strength parameters are recommended to be c=0.2kg/$\textrm{cm}^2$ and ø=35$^{\circ}$for standard rubble if the compressive strength of parent rock is greater than 300kg/$\textrm{cm}^2$, quoting from research results by Jun-ichi Mizukami(1991), But this facts have never been certified in Korea because there was not large-scale triaxial test apparatus until 2000 in Korea. Firstly in Korea, the large-scale triaxial test (sample diameter, 30cm and height, 60cm) on the rubble originated from porous basalt rock in North-Cheju was accomplished. Then strength parameters for basalt rubble produced in North-Cheju are recommended to be c=0.3kg/$\textrm{cm}^2$ and ø=36$^{\circ}$if the compressive strength of parent rock is greater than 400kg/$\textrm{cm}^2$.

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