• Title/Summary/Keyword: Frequency of Computer Use

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On OFDM Subcarrier Allocation Strategies for Soft Hand-off in Cellular Systems

  • Kim, Chan-Hong;Lee, Jung-Woo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.3
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    • pp.784-793
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    • 2012
  • This paper deals with subcarrier allocation strategies for soft hand-over in OFDMA-based cellular systems. Two possible subcarrier allocation methods are considered for soft hand-over. One method is to use an identical subcarrier set between the two cells participating in the hand-over. The other is to use different subcarrier sets between the two cells. As expected, the different subcarrier strategy is better in terms of diversity order and BER than the identical subcarrier strategy. It will be shown that the BER performance difference between the two strategies is more noticeable with contiguous subcarrier allocation. But the different subcarrier strategy consumes twice more frequency resources than the other, and there is a trade-off between the two strategies in terms of BER and frequency resources. By considering the trade-off, we also propose a subcarrier allocation strategy for soft hand-over.

연계(連繫)된 전력계통(電力系統)의 최적(最適) 부하주파수(負荷周波數) 제어(制御)

  • Han, Man-Chun;Jang, Seong-Hwan
    • Proceedings of the KIEE Conference
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    • 1979.08a
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    • pp.119-120
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    • 1979
  • A linear state equation of the first order differential form relating the load-frequency dynamic characteristics of interconnected power systems was derived for use in computer simulation. A now solution of the algebraic matrix riccati equation for application in quadratic optimal controllor and least-square state estimator dermination was developed. The program for a dynamic state equation for two interconnected control areas was developed. The optimized load-frequency deviation was analysed and a numerical analysis was tried based on the computer simulation. It was shown that the dynamic response of th loed-frequency could be optimized with weighting factors IR and Q. The result was that the load-frequency and the tie-line deviation were visibly reduced.

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Analysis of bibliographic data fields by frequency of use in public libraries (공공도서관의 사용빈도별 서지 데이터 필드 분석)

  • Kim, Joo-Yong;Shin, Pan-Seop
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2021.07a
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    • pp.245-246
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    • 2021
  • 본 논문에서는 차세대 서지 기술 방법인 BIBFRAME의 적용성을 향상하기 위한 사전 연구로, 공공도서관의 서지 데이터 필드를 분석하여 사용빈도가 높은 주요 필드를 선정하고 각 필드별 태그의 의미를 제시한다. 주요 필드 선정은 실제 사용 중인 최신 서지 데이터를 대상으로 분석을 진행하며, 이를 통해 공공도서관의 다양한 KORMARC 서지 데이터 필드 중 BIBFRAME 변환을 위한 주요 데이터 필드를 추출한다.

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Moving-Target Tracking Based on Particle Filter with TDOA/FDOA Measurements

  • Cho, Jeong-A;Na, Han-Byeul;Kim, Sun-Woo;Ahn, Chun-Soo
    • ETRI Journal
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    • v.34 no.2
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    • pp.260-263
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    • 2012
  • In this letter, we propose a moving-target tracking algorithm based on a particle filter that uses the time difference of arrival (TDOA)/frequency difference of arrival (FDOA) measurements acquired by distributed sensors. It is shown that the performance of the proposed algorithm, based on the particle filter, outperforms the one based on the extended Kalman filter. The use of both the TDOA and FDOA measurements is shown to be effective in the moving-target tracking. It is proven that the particle filter deals with the nonlinear nature of the movingtarget tracking problem successfully.

Electric power system effect investigation of large size digital signal accident thought in digital age (디지털시대의 대형사고의 전기적 영향 고찰)

  • Kang, Tae-Keun
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.575-580
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    • 2004
  • The latest equipment automatic Intelligence of digital base done large size equipment appear in succession. That run by voltage electric current(mA, mV, ${\mu}A,\;{\mu}V$) that outline is microscopic of action of accuracy large size equipment of this digital base is bulk. Have received influence that is great in river electric field by installment that use computer. Most of domestic working voltage from service entrance extra-high voltage and working voltage of commercial frequency 60Hz working voltage 220V that use our country outside 1 country in interior of 22.900V for semiconductor use computer use digital installment of appliance as well as various smalls of digital base, middle, large size that safety is these fine voltage electric current that is not enough direct admonition hundred vast damage give can. Also, already act in surge circle and impulse transient phenomena such as several thousands, myriads, strong bit error more than billions time to digital fine electronic circuit by mistake use of using electric facility system of system electric power.

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A Study of Variables Affecting the Information Literacy (정보활용능력에 영향을 미치는 변인에 관한 연구)

  • Park Nam-Jin;Choi Eun-Ju
    • Journal of the Korean Society for Library and Information Science
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    • v.40 no.3
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    • pp.215-232
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    • 2006
  • This study analyzed factors affecting the information literacy of students and the effects of information literacy education. Based on the results. the study aimed at presenting plans for the enhancement of information literacy education hereafter. The differences in the mean value of computer operating skill, library related knowledge, frequency of library use and information literacy prior to and after taking the course in information literacy education were compared. The result of hypothesis testing on the effects of previous educational experience, computer operating skill, knowledge of library use and frequency of information use have on information literacy, as well as the relationship between course satisfaction and opinion after taking the lecture were all adopted. The result of the study implied that more systematic and concrete information literacy education program is urgently needed.

Wavelet-Based Watermarking using Threshold Values and PN-Code for Copyright Protection (저작권 보호를 위한 임계값과 PN-Code를 이용한 웨이블릿 영역에서의 워터마킹)

  • 정용훈;오휘빈;최영규;이준환;이상범
    • Journal of the Korea Computer Industry Society
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    • v.4 no.4
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    • pp.561-568
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    • 2003
  • This paper suggests that watermarking technique make use of Threshold Values and PN code for preservation of copyright. To protect copyright, six binary images that are generated by a Dynamic Threshold Value to LSB(least significant bit) of wavelet coefficient through wavelet conversion and watermark image use PN code to each frequency sphere-HL1, LH1, HL2, LH2, HL3, LH3, decide coordinates, operate XOR, and insert watermark. They put the sphere except from low frequency which has much image deterioration and high frequency which has weak loss compression in watermark. As an experimental result, we acquired watermark inserting image that has little image deterioration and extract watermark strongly.

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Multi-illumination digital holographic microscopy

  • Phan, Anh-Hoang;Kim, Nam;Park, Jae-Hyeung
    • Proceedings of the Optical Society of Korea Conference
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    • 2009.10a
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    • pp.323-324
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    • 2009
  • In this paper, we use multi-point sources to illuminate the sample in digital holographic microscopy. The resolution of digital holographic microscopy is enhanced without shifting the CCD camera. The specimen is illuminated from many directions by using multi-point sources which are easily created by a lens-array. The high frequency information of specimen can be captured at a fixed position of CCD camera. All information is then synthesized to increase the resolution.

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An Efficient Algorithm for Similarity Search in Large Biosequence Database (대용량 유전체를 위한 효율적인 유사성 검색 알고리즘)

  • Jeong, In-Seon;Park, Kyoung-Wook;Lim, Hyeong-Seok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.1073-1076
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    • 2005
  • Since the size of biosequence database grows exponentially every year, it becomes impractical to use Smith-Waterman algorithm for exact sequence similarity search. For fast sequence similarity search, researchers have been proposed heuristic methods that use the frequency of characters in subsequences. These methods have the defect that different sequences are treated as the same sequence. Because of using only the frequency of characters, the accuracy of these methods are lower than Smith-Waterman algorithm. In this paper, we propose an algorithm which processes query efficiently by indexing the frequency of characters including the positional information of characters in subsequences. The experiments show that our algorithm improve the accuracy of sequence similarity search approximately 5${\sim}$20% than heuristic algorithms using only the frequency of characters.

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The Use of Regularizers for High-Frequency Apodization in Filtered Backprojection (Filtered Backprojection에서 정착자를 사용한 고주파 감쇠)

  • Lee, Soo-Jin;Kim, Yong-Hoh
    • The Journal of Engineering Research
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    • v.2 no.1
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    • pp.49-56
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    • 1997
  • In emission computed tomography, statistical reconstruction methods in the context of a Bayesian framework have been a topic of interest over the last decade. This was mainly due to the fact that Bayesian approaches can incorporate a priori information into the reconstruction algorithm. Although these approaches can exhibit good performance, their applications to the clinic is hindered mainly by their high computational cost. On the other hand, the speed and simplicity of the filtered backprojection (FBP) algorithm have led to its widespread use in most clinical applications. In this work, we use spline models, which have been quite useful in Bayesian reconstruction, as regularizers for high-frequency apodization in FBP algorithm and show that the effects of using spline models as priors in Bayesian reconstruction can also be achieved in FBP reconstruction.

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