• Title/Summary/Keyword: 거리합

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Dual-band Monopulse Receiver for Tracking Radar (추적 레이다용 Dual-band 모노펄스 수신기)

  • Yang Seong-Uk;Park Dong-Min;Na Young-Jin
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.8 s.111
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    • pp.767-772
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    • 2006
  • The receiver of this paper is Dual-band monopulse type for prototype of tracking radar. Localization of radar technology is an issue of SamsungThales and go into development. Dual-band radar in comparison with Single-band radar requires higher cost and power consumption but there are many advantages of dealing with jamming, detection range, image signal rejection, cloud-rain influence, clutter, resolution. The receiver is comprised of X-band RF head module, Ka-band RF head module and common IF module. Each signal of X-band and Ka-band is selected by the switch in If module. Phase shifter in IF module of local stage controls the phase of sum, azimuth, elevation channel. In the test result, gain is $40{\pm}3 dB$, isolation of transmitter/receiver is 39 dBc, dynamic range is 110 dB and noise figure of each channel is 4.5dB and 6.9dB.

Model Verification Algorithm for ATM Security System (ATM 보안 시스템을 위한 모델 인증 알고리즘)

  • Jeong, Heon;Lim, Chun-Hwan;Pyeon, Suk-Bum
    • Journal of the Institute of Electronics Engineers of Korea TE
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    • v.37 no.3
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    • pp.72-78
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    • 2000
  • In this study, we propose a model verification algorithm based on DCT and neural network for ATM security system. We construct database about facial images after capturing thirty persons facial images in the same lumination and distance. To simulate model verification, we capture four learning images and test images per a man. After detecting edge in facial images, we detect a characteristic area of square shape using edge distribution in facial images. Characteristic area contains eye bows, eyes, nose, mouth and cheek. We extract characteristic vectors to calculate diagonally coefficients sum after obtaining DCT coefficients about characteristic area. Characteristic vectors is normalized between +1 and -1, and then used for input vectors of neural networks. Not considering passwords, simulations results showed 100% verification rate when facial images were learned and 92% verification rate when facial images weren't learned. But considering passwords, the proposed algorithm showed 100% verification rate in case of two simulations.

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Image Enhancement Using Adaptive Region-based Histogram Equalization for Multiple Color-Filter Aperture System (다중 컬러필터 조리개 시스템을 위한 적응적 히스토그램 평활화를 이용한 영상 개선)

  • Lee, Eun-Sung;Kang, Won-Seok;Kim, Sang-Jin;Paik, Joon-Ki
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.2
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    • pp.65-73
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    • 2011
  • In this paper, we present a novel digital multifocusing approach using adaptive region-based histogram equalization for the multiple color-filter aperture (MCA) system with insufficient amount of incoming light. From the image acquired by the MCA system, we can estimate the depth information of objects at different distances by measuring the amount of misalignment among the RGB color planes. The estimated depth information is used to obtain multifocused images together with the process of the region-of-interests (ROIs) classification, registration, and fusion. However, the MCA system results in the low-exposure problem because of the limited size of the apertures. For overcoming this problem, we propose adaptive region-based histogram equalization. Based on the experimental results, the proposed algorithm is proved to be able to obtain in-focused images under the low light level environment.

Vehicle Speed Measurement using SAD Algorithm (SAD 알고리즘을 이용한 차량 속도 측정)

  • Park, Seong-Il;Moon, Jong-Dae;Ko, Young-Hyuk
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.5
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    • pp.73-79
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    • 2014
  • In this paper, we proposed the mechanism which can measure traffic flow and vehicle speed on the highway as well as road by using the video and image processing to detect and track cars in a video sequence. The proposed mechanism uses the first few frames of the video stream to estimate the background image. The visual tracking system is a simple algorithm based on the sum of absolute frame difference. It subtracts the background from each video frame to produce foreground images. By thresholding and performing morphological closing on each foreground image, the proposed mechanism produces binary feature images, which are shown in the threshold window. By measuring the distance between the "first white line" mark and the "second white line"mark proceeding, it is possible to find the car's position. Average velocity is defined as the change in position of an object divided by the time over which the change takes place. The results of proposed mechanism agree well with the measured data, and view the results in real time.

Statistical Problems in the Determination of Normal Manges from Laboratory Data (임상 검사 결과로부터 정상 범위 추정에 대한 통계학적 연구)

  • Song, Hae-Hiang
    • Journal of Preventive Medicine and Public Health
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    • v.17 no.1
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    • pp.231-238
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    • 1984
  • Normal range has use mainly in the first phase of the diagnostic process, that is, to screen or to raise ideas about possible pathology. The traditional method of determining it is based on the probability paper or on the mean plus or minus two standard deviations. These methods are often turned out to be vague and impractical. The percentile method is adequate and flexible, though. The appropriate limit of lower and upper points should be chosen by considering medical aspects above all things and also the reliability of the range determined by the standard error. The results of normal range are interesting, strictly speaking, only for the hospital concerned. Differences exist between the normal ranges reported by various sources (Bezemer et al, 1983). It would be best to establish the normal range based on a population comparable to a group of individuals to whom the normal range is to serve as a norm.

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A study on the Application of Non Prism Totalstation to Facility Survey (시설물측량에서의 무프리즘 토털스테이션 활용성 연구)

  • 박경식;이현직;함창학
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.21 no.2
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    • pp.155-164
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    • 2003
  • The entrance of non prism totalstation brought the application possibility to many fields including a topographic survey and a facility measurement. In this research we would try to examine the errors and the problems which will be happened in measuring object with non prism totalstation and to evaluate the accuracy and applicability. For this purposes, We checked accuracy change according to the observation ang1e and material of the object, and analyzed how much accuracy was effected with the color of the object surface and laser divergency which is proportional to the distance. By measuring the facility practically and analyzing it's results, We evaluated possibility of practical use of a non prism totalstation for a facility measurement. Consequently, We propose that the observation accuracy of non prism totalstation is not depend on the hardness or material of the object and can get a good result only when we use non prism totalstation with coaxial focusing system for a facility survey.

M & S Tool for Analyzing the Detection Performance in Bistatic Radar (바이스태틱 레이더의 탐지 성능 분석용 M & S Tool)

  • Kim, Kwan-Soo;Youn, Jae-Hyuk;Yang, Hoon-Gee;Chung, Young-Seek;Lee, Won-Woo;Bae, Kyung-Bin
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.6
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    • pp.631-640
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    • 2011
  • This paper proposes a M & S Tool for simulating the detection performance in the bistatic radar system. After examing the interrelationship among the bistatic radar parameters, $P_d$(probability of detection), $P_{fa}$(probability of false alarm) and ��SNR of the received signal, we analyze the range of the bistatic radar range product and range sum. We derive the number of integration of the received pulses that satisfies the required detection performance of the bistatic radar system, along with the analysis of the performance degradation in the jammer scenario. Finally, the analyzed results are implemented in the M & S Tool which consists of 4 modules.

Optimizing dispatching strategy based on multicriteria heuristics for AGVs in automated container terminal (자동화 컨테이너 터미널의 복수 규칙 기반 AGV 배차 전략 최적화)

  • Kim, Jeong-Min;Choe, Ri;Park, Tae-Jin;Ryu, Kwang-Ryul
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2011.06a
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    • pp.218-219
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    • 2011
  • This paper focuses on dispatching strategy for AGVs(Automated Guided Vehicle). The goal of AGV dispatching problem is allocating jobs to AGVs to minimizing QC delay and AGV total travel distance. Due to the highly dynamic nature of container terminal environment, the effect of dispatching is hard to predict thus it leads to frequent modification of dispatching results. Given this situation, single rule-based approach is widely used due to its simplicity and small computational cost. However, single rule-based approach has a limitation that cannot guarantee a satisfactory performance for the various performance measures. In this paper, dispatching strategy based on multicriteria heuristics is proposed. Proposed strategy consists of multiple decision criteria. A muti-objective evolutionary algorithm is applied to optimize weights of those criteria. The result of simulation experiment shows that the proposed approach outperforms single rule-based dispatching approaches.

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Disparity estimation using wavelet transformation and reference points (웨이블릿 변환과 기준점을 이용한 변위 추정)

  • 노윤향;고병철;변혜란;유지상
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.2A
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    • pp.137-145
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    • 2002
  • In the method of 3D modeling, stereo matching method which obtains three dimensional depth information from the two images is taken from the different view points. In general, it is very essential work for the 3D modeling from 2D stereo images to estimate the exact disparity through fading the conjugate pair of pixel from the left and right image. In this paper to solve the problems of the stereo image disparity estimation, we introduce a novel approach method to improve the exactness and efficiency of the disparity. In the first place, we perform a wavelet transformation of the stereo images and set the reference points in the image by the feature-based matching method. This reference points have very high probability over 95 %. In the base of these reference points we can decide the size of the variable block searching windows for estimating dense disparity of area based method and perform the ordering constraint to prevent mismatching. By doing this, we could estimate the disparity in a short time and solve the occlusion caused by applying the fried-sized windows and probable error caused by repeating patterns.

Related Term Extraction with Proximity Matrix for Query Related Issue Detection using Twitter (트위터를 이용한 질의어 관련 이슈 탐지를 위한 인접도 행렬 기반 연관 어휘 추출)

  • Kim, Je-Sang;Jo, Hyo-Geun;Kim, Dong-Sung;Kim, Byeong Man;Lee, Hyun Ah
    • KIPS Transactions on Software and Data Engineering
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    • v.3 no.1
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    • pp.31-36
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    • 2014
  • Social network services(SNS) including Twitter and Facebook are good resources to extract various issues like public interest, trend and topic. This paper proposes a method to extract query-related issues by calculating relatedness between terms in Twitter. As a term that frequently appears near query terms should be semantically related to a query, we calculate term relatedness in retrieved documents by summing proximity that is proportional to term frequency and inversely proportional to distance between words. Then terms, relatedness of which is bigger than threshold, are extracted as query-related issues, and our system shows those issues with a connected network. By analyzing single transitions in a connected network, compound words are easily obtained.