• Title/Summary/Keyword: electronic scale

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MR Brain Image Segmentation Using Clustering Technique

  • Yoon, Ock-Kyung;Kim, Dong-Whee;Kim, Hyun-Soon;Park, Kil-Houm
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.450-453
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    • 2000
  • In this paper, an automated segmentation algorithm is proposed for MR brain images using T1-weighted, T2-weighted, and PD images complementarily. The proposed segmentation algorithm is composed of 3 steps. In the first step, cerebrum images are extracted by putting a cerebrum mask upon the three input images. In the second step, outstanding clusters that represent inner tissues of the cerebrum are chosen among 3-dimensional (3D) clusters. 3D clusters are determined by intersecting densely distributed parts of 2D histogram in the 3D space formed with three optimal scale images. Optimal scale image best describes the shape of densely distributed parts of pixels in 2D histogram. In the final step, cerebrum images are segmented using FCM algorithm with it’s initial centroid value as the outstanding cluster’s centroid value. The proposed segmentation algorithm complements the defect of FCM algorithm, being influenced upon initial centroid, by calculating cluster’s centroid accurately And also can get better segmentation results from the proposed segmentation algorithm with multi spectral analysis than the results of single spectral analysis.

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Scanning Kelvin Probe Microscope analysis of Nano-scale Patterning formed by Atomic Force Microscopy in Silicon Carbide (원자힘현미경을 이용한 탄화규소 미세 패터닝의 Scanning Kelvin Probe Microscopy 분석)

  • Jo, Yeong-Deuk;Bahng, Wook;Kim, Sang-Cheol;Kim, Nam-Kyun;Koo, Sang-Mo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.32-32
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    • 2009
  • Silicon carbide (SiC) is a wide-bandgap semiconductor that has materials properties necessary for the high-power, high-frequency, high-temperature, and radiation-hard condition applications, where silicon devices cannot perform. SiC is also the only compound semiconductor material. on which a silicon oxide layer can be thermally grown, and therefore may fabrication processes used in Si-based technology can be adapted to SiC. So far, atomic force microscopy (AFM) has been extensively used to study the surface charges, dielectric constants and electrical potential distribution as well as topography in silicon-based device structures, whereas it has rarely been applied to SiC-based structures. In this work, we investigated that the local oxide growth on SiC under various conditions and demonstrated that an increased (up to ~100 nN) tip loading force (LF) on highly-doped SiC can lead a direct oxide growth (up to few tens of nm) on 4H-SiC. In addition, the surface potential and topography distributions of nano-scale patterned structures on SiC were measured at a nanometer-scale resolution using a scanning kelvin probe force microscopy (SKPM) with a non-contact mode AFM. The measured results were calibrated using a Pt-coated tip. It is assumed that the atomically resolved surface potential difference does not originate from the intrinsic work function of the materials but reflects the local electron density on the surface. It was found that the work function of the nano-scale patterned on SiC was higher than that of original SiC surface. The results confirm the concept of the work function and the barrier heights of oxide structures/SiC structures.

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Management Efficiency of High-growth Electrical and Electronics Industry (고성장 전기·전자사업의 경영효율성)

  • Kang, Da-Yeon;Lee, Ki-Se
    • The Journal of the Korea Contents Association
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    • v.19 no.8
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    • pp.151-158
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    • 2019
  • The high-technological in the electric and electronic industries is recognized in overseas markets as well. However, the competition for technologies in these industries is increasing. Therefore, electric and electronic firms should be more efficient in their production. so, This paper analyzes the efficiency of High-growth Electrical and Electronics firms using DEA model. We evaluate the CCR, BBC efficiency and RTS(return to scale) of 20 Korean high-growth Electrical and Electronics firms. There are a total of 12 efficient DMUs with a BCC of 1. There are a total of 4 efficient DMUs with a CCR of 1. A total of 11 DMUs were IRS in Scale Efficiency and a total of 6 DMUs were CRS in Scale Efficiency and a total of 3 DMUs were DRS in Scale Efficiency. We also suggest the Electrical and Electronics firms which can be benchmarked based on analyzed information.

A Study on Real-time Implementing of Time-Scale Modification (음성 신호 시간축 변환의 실시간 구현에 관한 연구)

  • Han, Dong-Chul;Lee, Ki-Seung;Cha, Il-Hawan;Youn, Dae-Hee
    • The Journal of the Acoustical Society of Korea
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    • v.14 no.2
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    • pp.50-61
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    • 1995
  • A time scale modification method yielding rate-modified speech while conserving the characteristic of speech was implemented in real-time using a goneral purpose digital signal processor. Time scale modification changed pronunciation speed only, producing a time difference between the input signal and the modified signal, making it impossible to implement it in real-time. In this thesis, a system was implemented to remove the time difference between the input and modified signals. Speech signals slowed down or speeded up by a physical time scale modification method, such as adjusting the motor speed of the cassett tape recorder, was used as the input signal. Physical modification that controled only the inter speed of the cassette tape player distorted the pitch period of the original speech. In this study, a real-time system was implemented so that the pitch-distorted speech was reconstructed back to the original by fractional sampling pitch shifting using an FIR filter, and this signal was time scale modified to match the cassette tape recorder motor speed using SOLA time-scale medification. In experiments using speech signals medifiedby the proposed method, results obtained using a 16-bit resolution ADSP2101 processor and using computer simulations employing floating point operations showed about the same average frame signal-to-noise ratio of about 20 dB.

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Comparison of subjective video quality assessment methods for multimedia applications (멀티미디어 응용을 위한 주관적 동영상 품질평가 방법의 비교분석)

  • Choe, Ji-Hwan;Jeong, Tae-Uk;Choi, Hyun-Soo;Lee, Eun-Jae;Lee, Sang-Wook;Lee, Chul-Hee
    • Journal of Broadcast Engineering
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    • v.12 no.2
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    • pp.177-184
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    • 2007
  • In this paper, we compared two subjective assessment methods DSCQS(Double Stimulus Continuous Quality Scale method) and ACR(Absolute Category Rating). These methods are widely used in order to evaluate video quality for multimedia application. We performed subjective quality tests using DSCQS and ACR methods. The subjective scores obtained by the DSCQS and ACR methods show that these methods are highly correlated in terms of MOS(Mean Opinion Score) and have slightly lower correlation in terms of DMOS(Difference Mean Opinion Score). The results indicate that ACR method is an effective subjective quality assessment method, which shows compatible performance with DSCQS method and can evaluate a larger number of video sequences.

Near-Optimal Low-Complexity Hybrid Precoding for THz Massive MIMO Systems

  • Yuke Sun;Aihua Zhang;Hao Yang;Di Tian;Haowen Xia
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.4
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    • pp.1042-1058
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    • 2024
  • Terahertz (THz) communication is becoming a key technology for future 6G wireless networks because of its ultra-wide band. However, the implementation of THz communication systems confronts formidable challenges, notably beam splitting effects and high computational complexity associated with them. Our primary objective is to design a hybrid precoder that minimizes the Euclidean distance from the fully digital precoder. The analog precoding part adopts the delay-phase alternating minimization (DP-AltMin) algorithm, which divides the analog precoder into phase shifters and time delayers. This effectively addresses the beam splitting effects within THz communication by incorporating time delays. The traditional digital precoding solution, however, needs matrix inversion in THz massive multiple-input multiple-output (MIMO) communication systems, resulting in significant computational complexity and complicating the design of the analog precoder. To address this issue, we exploit the characteristics of THz massive MIMO communication systems and construct the digital precoder as a product of scale factors and semi-unitary matrices. We utilize Schatten norm and Hölder's inequality to create semi-unitary matrices after initializing the scale factors depending on the power allocation. Finally, the analog precoder and digital precoder are alternately optimized to obtain the ultimate hybrid precoding scheme. Extensive numerical simulations have demonstrated that our proposed algorithm outperforms existing methods in mitigating the beam splitting issue, improving system performance, and exhibiting lower complexity. Furthermore, our approach exhibits a more favorable alignment with practical application requirements, underlying its practicality and efficiency.

A Study on the Space Element of Public Library Buildings as a Information Center (정보센터로서의 공공도서관 공간요소에 관한 연구)

  • 이상호;황창석
    • Korean Institute of Interior Design Journal
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    • no.17
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    • pp.87-93
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    • 1998
  • As the varification of public library services has been come true through the increase of multimedia information accompanied with the development of information tachnology and the advent of various electronic materials the repetitive and labo intensive process has been cut down by the development of network system. Recentrly the electronic library using outside networks electronic library facilities at the time of their new contructions. In this study it is aimed that the outline of the library planning is presented with the case analyses of domestic and foreign libraries especially concerning the kinds and features of the required spaces for electronic libraries their scale basic facilities. The conclusions of this study are : First the spaces requred for electronic library are as mentioned below: catalgue are equipped with terminal information service center reference room electronic reading room computer training center and conference room. Second computer room for management and electronic information center has been made recently in the Library of Seoul City. The space for librarians room is to be 5.48$m^2$ per person on average and for electronic information center of library provided with an exclusive use is to be 5.1$m^2$ per person.

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