• Title/Summary/Keyword: 3D (3Dimensional)

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Development of Videooculograph for Vestibular Function Test (전정 기능 평가를 위한 영상 안구 운동 측정 시스템의 개발)

  • 김수찬;남기창;이원선;김덕원
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.40 no.3
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    • pp.189-198
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    • 2003
  • Videooculography (VOG) is one of the eye-movement measurement methods used for objective evaluation of vestibule -ocular reflex. A key feature of VOG is to estimate accurately the center of pupil and ocular torsion with being less influenced by the upper eyelid droop, eyelashes, corneal reflection, and eye blinks. Especially, it Is important to find the accurate center of the pupil in 3-D VOG because the inaccurate pupil center causes significant errors on measuring torsional eye movement. A new algorithm was proposed to find the center of pupil which is a little influenced by factors mentioned above. In this study, real time three-dimensional VOG which can measure horizontal, vortical, torsional eye movements, and the diameter of pupil was implemented using the proposed method.

Computational Study on OH and Cl Initiated Oxidation of 2,2,2-Trifluoroethyl Trifluoroacetate (CF3C(O)OCH2CF3)

  • Singh, Hari Ji;Tiwari, Laxmi;Rao, Pradeep Kumar
    • Bulletin of the Korean Chemical Society
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    • v.35 no.5
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    • pp.1385-1390
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    • 2014
  • Hydrofluoroethers (HFEs) are developed as a suitable for the replacement of environmentally hazardous CFCs and are termed as third generation refrigerants. One of the major products of decomposition of HFEs in the atmosphere is a fluoroester. The present study relates to the OH and Cl initiated oxidation of $CF_3C(O)OCH_2CF_3$ formed from the oxidation of HFE-356mff. The latter is used as a solvent in the industry and reaches the atmosphere without any degradation. Kinetics of the titled molecule has been studied at MPWB1K/6-31+G(d,p) level of theory. Single point energy calculations have been made at G2(MP2) level of theory and barrier heights are determined. The rate constants are calculated using canonical transition state theory. Tunnelling correction are made using one-dimensional Eckart potential barrier. The rate constant calculated during the present study are compared with the experimental values determined using relative rate method and FTIR detection technique.

Synthesis, Characterization, Luminescence and Biological Activity of Two Lanthanide Complexes Involving Mixed Ligands

  • Ma, De-Yun;Guo, Hai-Fu;Qin, Liang;Xu, Jun
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2774-2780
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    • 2013
  • Two new isostructural dinuclear complexes, $Ln_2(4-cpa)_6(bpy)_2$ (Ln = Eu (1); Tb (2), 4-cpa = 4-chlorophenylacetate, bpy = 2,2'-bipyridine), have been hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction and single-crystal X-ray diffraction. The lanthanide ions are bridged by two bidentate and two terdentate carboxylate groups to give centrosymmetric dimers with $Ln{\cdots}Ln$ separations of 3.967(2) and 3.956(3) ${\AA}$, respectively. Each metal atom is nine-coordinate and exhibits a distorted tricapped trigonal prismatic geometry. Three-dimensional fluorescence spectra show that both 1 and 2 emit bright red and green luminescence at room temperature, with long lifetimes of up to 0.369 ms (at 614 nm) and 0.432 ms (at 543 nm), respectively. Moreover, poor luminescence efficiency has been noted for complex 2. The 4-Hcpa ligand and complexes 1-2 have been screened for their phytogrowth-inhibitory activities against Brassica napus L. and Echinochloa crusgalli L., and the results are compared with the activity of quizalofop-P-ethyl.

Topological phase transition according to internal strain in few layer Bi2Se3 thin film grown via a self-organized ordering process

  • Kim, Tae-Hyeon;Park, Han-Beom;Jeong, Gwang-Sik;Chae, Jae-Min;Hwang, Su-Bin;Jo, Man-Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.272.1-272.1
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    • 2016
  • In a three-dimensional topological insulator Bi2Se3, a stress control for band gap manipulation was predicted but no systematic investigation has been performed yet due to the requirement of large external stress. We report herein on the strain-dependent results for Bi2Se3 films of various thicknesses that are grown via a self-organized ordering process. Using small angle X-ray scattering and Raman spectroscopy, the changes of d-spacings in the crystal structure and phonon vibration shifts resulted from stress are clearly observed when the film thickness is below ten quintuple layers. From the UV photoemission/inverse photoemission spectroscopy (UPS/IPES) results and ab initio calculations, significant changes of the Fermi level and band gap were observed. The deformed band structure also exhibits a Van Hove singularity at specific energies in the UV absorption experiment and ab initio calculations. Our results, including the synthesis of a strained ultrathin topological insulator, suggest a new direction for electronic and spintronic applications for the future.

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A Study on PDOP due to the Position Error of Acoustic Sensors in the 3D TDOA Positioning System (3차원 TDOA 위치 측정 시스템에서 음향 센서의 위치 오차에 따른 PDOP에 관한 연구)

  • Oh, Jongtaek
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.199-205
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    • 2015
  • Indoor positioning technology has been developed very actively for the smart phone handheld by most users. Especially, many TDOA positioning systems using acoustic signal have been studied, and it estimates the smart phone position by measuring the distance between the smart phone speaker and the microphones which is installed to receive the acoustic signal from the smart phone, and by calculating the hyperbolic equations. But there are always errors for the distance measurements, and furthermore the microphone installation error produces huge position estimation error. In this paper, the position estimation error due to the position error of acoustic sensor in the 3 dimensional TDOA positioning system, is analyzed by PDOP simulation and experiment.

Effect of the Hole on the Tensile Fatigue Properties of CFRP Laminates

  • Lee, Yeon-Soo;Ben, Goichi;Lee, Se-Hwan
    • Advanced Composite Materials
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    • v.18 no.1
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    • pp.43-59
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    • 2009
  • The current study assessed the effect of a bolt hole on tensile fatigue properties of CFRP laminates. Two specimens, i.e. $[(0/90)_3]S$, $[(0/45/90/-45)_2]_S$, were analyzed using a finite element method and were experimentally tested for cases, both with and without a hole, whose diameter corresponded to 0.12 times the specimen width. Delamination positions predicted by a 3-dimensional static finite element analysis were matched well to those observed by an ultrasonic imaging system in the middle of fatigue test. A hole whose diameter corresponds to 0.12 times the specimen width caused the fatigue strength to decrease by 9% and 11% under 5 Hz loading frequency, and by 22% and 25% under 10 Hz loading frequency for $[(0/90)_3]_S$ and $[(0/45/90/-45)_2]_S$, respectively. Because the decrease in sectional area due to the hole was normalized in calculation of the tensile strength, a stress concentration around the hole is believed to induce the strength degradation of fatigue specimens. From the finite element analyses, the stress concentration factor around a hole was expected as 8.8 and 9.5 for $[(0/90)_3]_S$ and $[(0/45/90/-45)_2]_S$, respectively.

CFD Study on Aerodynamic Power Output of 6 MW Offshore Wind Farm According to the Wind Turbine Separation Distance (CFD를 활용한 6 MW 해상풍력발전단지의 풍력터빈 이격거리에 따른 공기역학적 출력 변화연구)

  • Choi, Nak-Joon;Nam, Sang-Hyun;Jeong, Jong-Hyun;Kim, Kyung-Chun
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.8
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    • pp.1063-1069
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    • 2011
  • This paper presents aerodynamic power outputs of wind turbine of 6 MW wind farm composed of 3 sets of 2 MW wind turbine according to the separation distance by using CFD. Layout design including offshore wind farm and onshore wind farm is key factor for the initial investment cost, annual energy production and maintenance cost. For each wind turbine rotor, not actuator disc model with momentum source but full 3-dimensional model is used for CFD and it has a great technical meaning. The results of this study can be applied to the offshore wind farm layout design effectively.

The prediction of floating position of human model after wearing life-jacket based on the three dimensional modeling (3차원 모델링을 통한 구명복 착용 후 부양자세 예측)

  • Bi, Chong-Song;Kim, Dong-Joon;Park, Jong-Heon;Min, Kyong-Cheol;Lee, Jae-Sang
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.47 no.3
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    • pp.257-266
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    • 2011
  • Recently, the manufacturers of life-jacket are very interested in the acquisition of USCG(US Coast Guard) approval because the acquisition of USCG approval has an important role in the purchasing decision of the buyer's. Be based on criterion of USCG, we studied how to predict the change of floating position of human model with life-jacket to verify the backside restore. For this, in this study, the human model and the lifejacket was modeled in three dimension, the application program for prediction of floating position was developed, and plugged-in commercial program.

The Extract of 3D Road Centerline Using Video Camera (비디오 카메라를 이용한 3차원 도로중심선 추출)

  • Seo Dong-Ju;Lee Jong-Chool
    • International Journal of Highway Engineering
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    • v.8 no.1 s.27
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    • pp.65-75
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    • 2006
  • According to development of computer technology, the utilization of the fourth generation of digital photogrammetry progresses favorable. Especially the method of using digital video camera is very practicable and has an advantage such as a profitability for the amateur. In road field which if centrical facilities of national industry, this method was utilized to acquire road information for the safety diagnosis or maintenance. In this study, 3-dimensional position information of road centerline was extracted using digital video camera which has practicality and economical efficiency. This data could be a basic source in road information project.

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Segmentation of Immunohistochemical Breast Carcinoma Images Using ML Classification (ML분류를 사용한 유방암 항체 조직 영상분할)

  • 최흥국
    • Journal of Korea Multimedia Society
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    • v.4 no.2
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    • pp.108-115
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    • 2001
  • In this paper we are attempted to quantitative classification of the three object color regions on a RGB image using of an improved ML(Maximum Likelihood) classification method. A RGB color image consists of three bands i.e., red, green and blue. Therefore it has a 3 dimensional structure in view of the spectral and spatial elements. The 3D structural yokels were projected in RGB cube wherefrom the ML method applied. Between the conventionally and easily usable Box classification and the statistical ML classification based on Bayesian decision theory, we compared and reviewed. Using the ML method we obtained a good segmentation result to classify positive cell nucleus, negative cell Nucleus and background un a immuno-histological breast carcinoma image. Hopefully it is available to diagnosis and prognosis for cancer patients.

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