• Title/Summary/Keyword: IS605

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Calculation of Tree Height and Canopy Crown from Drone Images Using Segmentation

  • Lim, Ye Seul;La, Phu Hien;Park, Jong Soo;Lee, Mi Hee;Pyeon, Mu Wook;Kim, Jee-In
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.6
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    • pp.605-614
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    • 2015
  • Drone imaging, which is more cost-effective and controllable compared to airborne LiDAR, requires a low-cost camera and is used for capturing color images. From the overlapped color images, we produced two high-resolution digital surface models over different test areas. After segmentation, we performed tree identification according to the method proposed by , and computed the tree height and the canopy crown size. Compared with the field measurements, the computed results for the tree height in test area 1 (coniferous trees) were found to be accurate, while the results in test area 2 (deciduous coniferous trees) were found to be underestimated. The RMSE of the tree height was 0.84 m, and the width of the canopy crown was 1.51 m in test area 1. Further, the RMSE of the tree height was 2.45 m, and the width of the canopy crown was 1.53 m in test area 2. The experiment results validated the use of drone images for the extraction of a tree structure.

An Investigation of fan type anchorages applied to end of CFRP strips

  • Kara, M. Emin;Yasa, Mustafa
    • Steel and Composite Structures
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    • v.15 no.6
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    • pp.605-621
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    • 2013
  • CFRP strips are widely used nowadays for repair/strengthening or capacity increase purposes. Sharp bending at the ends of the CFRP strips is frequently encountered at these applications. In this study, Reinforced Concrete (RC) beam specimens that were produced with 10 MPa compression strength concrete were strengthened by using bonded CFRP strips with end anchorages to tension region. The parameters that were investigated in this study are the width of the strip, the number of applied fan anchorages and whether additional layer of CFRP patch is used or not at the strip ends. Specimens were strengthened with 100 mm wide CFRP strips with one or two anchorages at the ends. In addition CFRP patch with two and three anchorages at the ends were tested for investigating the effect of the patches. Specimens that were strengthened with three anchorages at the ends with patches were repeated with 60 and 80 mm wide CFRP strips. The most successful result was obtained from the specimen that was strengthened with 80 mm wide CFRP strips with 3 end anchorages and patches among the others at the experimental program. The numbers of anchorages that were applied to ends of CFRP strips were more effective than the width of the CFRP strips onto strength and stiffness of the specimens. Due to limited space at the ends of the strips at most three anchorages could be applied.

Quasi-Yagi Antenna for UHF RFID and GNSS Bands (UHF RFID 및 GNSS 대역용 준-야기 안테나)

  • Lee, Jong-Ig;Kim, Gun-Kyun;Yeo, Junho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.05a
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    • pp.57-58
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    • 2018
  • In this paper, we studied a design method for a quasi-Yagi antenna operating over a broad bandwidth covering the UHF RFID(902-928 MHz) and GNSS(1,164-1.605 MHz). The proposed antenna is composed of three elements(dipole, reflector, and director) and fed by a coplanar waveguide. To reduce its size, a balun is integrated inside the antenna, and the ends of both the dipole and reflector are bent. Broadband impedance matching was obtained by placing the director near to the dipole and loading a chip capacitor inside the antenna. The antenna, designed through simulations, was fabricated on an FR4 substrate with 0.8 mm thickness. The experiment results for the antenna characteristics agree very well with the simulation.

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Reconstruction of Linear Cyclic Codes (미지의 선형 순회부호에 대한 복원기법)

  • Chung, Ha-Bong;Jang, Hwan-Seok;Cho, Won-Chan;Park, Cheal-Sun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.10C
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    • pp.605-613
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    • 2011
  • In most digital communication systems over the noisy channel, some form of forward error correction scheme is employed for reliable communications. If one wants to recover the transmitted message without any knowledge of the error correcting codes employed, it is of utmost importance to figure out and reconstruct the error correcting codes. In this paper, we propose two algorithms of reconstructing linear cyclic codes from the corrupted received bit sequence, one for general linear binary cyclic codes and the other for Reed-Solomon codes. For two algorithms, we ran computer simulations and the performances are shown to be superior to those with the conventional LWM method.

A Study on the Data Fusion for Data Enrichment (데이터 보강을 위한 데이터 통합기법에 관한 연구)

  • 정성석;김순영;김현진
    • The Korean Journal of Applied Statistics
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    • v.17 no.3
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    • pp.605-617
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    • 2004
  • One of the best important thing in data mining process is the quality of data used. When we perform the mining on data with excellent quality, the potential value of data mining can be improved. In this paper, we propose the data fusion technique for data enrichment that one phase can improve data quality in KDD process. We attempted to add k-NN technique to the regression technique, to improve performance of fusion technique through reduction of the loss of information. Simulations were performed to compare the proposed data fusion technique with the regression technique. As a result, the newly proposed data fusion technique is characterized with low MSE in continuous fusion variables.

Design Flexible T-DMB Antenna with Common Mode Stub (Common Mode Stub를 이용한 Flexible T-DMB 안테나 구현)

  • Lee, Seon-Hyeon;Kim, Ho-Jin;Lee, Sang-Seok;Lee, Young-Hun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.6
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    • pp.605-612
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    • 2011
  • In this paper, we designed detachable T-DMB receiver antenna on the windshield of the car. Designed antenna is composed of only copper and feeders. To escape completely from driver's sight, it exists edging of windshield. Proposed antenna by considering body of properties and characteristics of the antenna input impedance have T-DMB frequency band(174~216 MHz). Proposed flexible antenna with Common Mode Stub is satisfied characteristics less than -5 dB antenna input return loss regardless of installation position on windshield.

Experimental study of moment redistribution and load carrying capacity of externally prestressed continuous composite beams

  • Chen, Shiming;Jia, Yuanlin;Wang, Xindi
    • Structural Engineering and Mechanics
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    • v.31 no.5
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    • pp.605-619
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    • 2009
  • A comparative experimental study of prestressed continuous steel-concrete composite beams was carried out. Two continuous composite beams were tested, one of which was plain continuous steel-concrete composite beam, while the other was a composite beam prestressed with external tendons. Cracking behavior and the load carrying capacity of the beams were investigated experimentally. Full plasticity was developed in the mid-span section each beam, the maximum moments attained at the internal support sections however were governed by local buckling which was related to the slenderness of composite section. It was found that in hogging moment regions, the ultimate resistance of an externally prestressed composite beam would be governed by either distortional lateral buckling or local buckling, or interactive mode of these two buckling patterns. The results show that exerting prestressing on a continuous composite beam with external tendons will increase the extent of internal force and moment redistribution in the beam. The influences of local and distortional buckling on the behaviors of the composite continuous beams are discussed. The Moment redistribution and the load carrying capacity of the prestressed continuous composite beams are evaluated, and it is found that at the ultimate state, the moment redistribution in the prestrssed continuous composite beams is greater than that in non-prestressed composite beams.

Communication Architecture of the IEC 61850-based Micro Grid System

  • Yoo, Byong-Kwan;Yang, Seung-Ho;Yang, Hyo-Sik;Kim, Won-Yong;Jeong, Yu-Seok;Han, Byung-Moon;Jang, Kwang-Soo
    • Journal of Electrical Engineering and Technology
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    • v.6 no.5
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    • pp.605-612
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    • 2011
  • As the power grids are integrated into one big umbrella called a "smart grid," communication protocol plays a key role in successful operations. The successful deployment of smart grid interoperability is a major hurdle that must be overcome. The micro grid, a small power system that distributes energy resource, is operated in diverse regions. Different vendors use different communication protocols in the operation of the micro grid. Recently, the IEC 61850 has been legislated to solve the interoperability problems in power utility automation. The present paper presents a micro grid system based on the IEC 61850 protocol. It consists of a micro grid monitoring system, a protocol converter that transforms serial data to IEC 61850 data, and distributed energy resource controllers for diverse DER nodes. A developed communication gateway can be deployed for DER controllers with serial links to exchange data with IEC 61850-based devices. The gateway can be extended to IEC 61850-based distribution automation systems, substation automation systems, or SCADA.

Determination of Sample Size and Comparison of Efficiency in Adaptive Cluster Sampling (적응집락추출에서 표본크기 결정과 추정량의 효율 비교)

  • NamKung, Pyong;Won, Hye-Kyoung;Choi, Jae-Hyuk
    • The Korean Journal of Applied Statistics
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    • v.20 no.3
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    • pp.605-618
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    • 2007
  • Adaptive sampling design is the selection procedure which depends on observed values of the variable of interest. It is the method which could be applied to the rare and unapproachable population. Adaptive cluster sampling strategies are more efficient than simple random sampling on equivalent sample size. Adaptive sampling with new estimators through the Rao-blackwell method have lower variance than Horvitz-Thompson (HT) and Hansen-Hurwitz (HH). Also, to determine suitable sample size, it was used expected sample and the method finding appropriate sample size by changing initial sample size were studied.

Reflection and propagation of plane waves at free surfaces of a rotating micropolar fibre-reinforced medium with voids

  • Anya, Augustine Igwebuike;Khan, Aftab
    • Geomechanics and Engineering
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    • v.18 no.6
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    • pp.605-614
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    • 2019
  • The present paper seeks to investigate propagation and reflection of waves at free surfaces of homogeneous, anisotropic and rotating micropolar fibre-reinforced medium with voids. It has been observed that, in particular when P-wave is incident on the free surface, there exist four coupled reflected plane waves traveling in the medium; quasi-longitudinal displacement (qLD) wave, quasi-transverse displacement (qTD) wave, quasi-transverse microrotational wave and a wave due to voids. Normal mode Analysis usually called harmonic solution method is adopted in concomitant with Snell's laws and appropriate boundary conditions in determination of solution to the micropolar fibre reinforced modelled problem. Amplitude ratios which correspond to reflected waves in vertical and horizontal components are presented analytically. Also, the Reflection Coefficients are presented using numerical simulated results in graphical form for a particular chosen material by the help of Mathematica software. We observed that the micropolar fibre-reinforced, voids and rotational parameters have various degrees of effects to the modulation, propagation and reflection of waves in the medium. The study would have impact to micropolar fibre-reinforecd rotational-acoustic machination fields and future works about behavior of seismic waves.