• Title/Summary/Keyword: False target

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The comparison of the BAD and the BCD methods in a P300-based concealed information test (P300 숨긴정보검사에서 BAD 방법과 BCD 방법의 비교)

  • Eom, Jin-Sup
    • Korean Journal of Forensic Psychology
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    • v.12 no.2
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    • pp.151-169
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    • 2021
  • In the P300-based concealed information test, most commonly used methods to detect whether a subject is lying are the bootstrapped amplitude difference (BAD) and the bootstrap correlation difference (BCD). Previous studies comparing the accuracy of the two methods reported inconsistent results. Most studies showed that the BAD is more accurate than the BCD, but some studies found that the BCD had a higher accuracy rate than the BAD. The purpose of the study is to identify conditions where the each method has higher accuracy compared to the other. In the result of Monte Carlo study, the false alarm rate of the BAD was generally higher than that of the BCD, and the hit rate of the BAD was higher than that of the BCD. Compared to the condition where the P300 latencies of probe and irrelevant were similar, the hit rate of the BCD was decreased when the P300 latency of probe was about 100 ms faster, and the hit rate of the BCD was increased when the P300 latency of probe was about 100 ms slower. When the P300 amplitude of the probe was slightly larger than that of the irrelevant and the P300 latency of probe was longer than that of target, the hit rate of the BCD was higher than that of the BAD. The reason why the false alarm rate of the BAD is higher than that of BCD and why the hit rate of the BCD is affected by the P300 latency of the probe were discussed.

A Separate Learning Algorithm of Two-Layered Networks with Target Values of Hidden Nodes (은닉노드 목표 값을 가진 2개 층 신경망의 분리학습 알고리즘)

  • Choi, Bum-Ghi;Lee, Ju-Hong;Park, Tae-Su
    • Journal of KIISE:Software and Applications
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    • v.33 no.12
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    • pp.999-1007
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    • 2006
  • The Backpropagation learning algorithm is known to have slow and false convergence aroused from plateau and local minima. Many substitutes for backpropagation announced so far appear to pay some trade-off for convergence speed and stability of convergence according to parameters. Here, a new algorithm is proposed, which avoids some of those problems associated with the conventional backpropagation problems, especially with local minima, and gives relatively stable and fast convergence with low storage requirement. This is the separate learning algorithm in which the upper connections, hidden-to-output, and the lower connections, input-to-hidden, separately trained. This algorithm requires less computational work than the conventional backpropagation and other improved algorithms. It is shown in various classification problems to be relatively reliable on the overall performance.

Automatic Co-registration of Cloud-covered High-resolution Multi-temporal Imagery (구름이 포함된 고해상도 다시기 위성영상의 자동 상호등록)

  • Han, You Kyung;Kim, Yong Il;Lee, Won Hee
    • Journal of Korean Society for Geospatial Information Science
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    • v.21 no.4
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    • pp.101-107
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    • 2013
  • Generally the commercial high-resolution images have their coordinates, but the locations are locally different according to the pose of sensors at the acquisition time and relief displacement of terrain. Therefore, a process of image co-registration has to be applied to use the multi-temporal images together. However, co-registration is interrupted especially when images include the cloud-covered regions because of the difficulties of extracting matching points and lots of false-matched points. This paper proposes an automatic co-registration method for the cloud-covered high-resolution images. A scale-invariant feature transform (SIFT), which is one of the representative feature-based matching method, is used, and only features of the target (cloud-covered) images within a circular buffer from each feature of reference image are used for the candidate of the matching process. Study sites composed of multi-temporal KOMPSAT-2 images including cloud-covered regions were employed to apply the proposed algorithm. The result showed that the proposed method presented a higher correct-match rate than original SIFT method and acceptable registration accuracies in all sites.

Evaluating Distribution Trends of Classification Accuracy by Triangular Training Operator in SAR/VIR FCC : A Case Study of Songkhla Lake Basin in Thailand (SAR/VIR FCC에서 삼각 트레이닝 도구에 의한 분류정확도 분포추세 평가: 태국의 송클라 호수 유역을 사례로)

  • Jung Sup Um
    • Journal of the Korean Geographical Society
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    • v.38 no.3
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    • pp.375-388
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    • 2003
  • This study mainly focuses on evaluating how the triangular training operator could improve classification accuracy in SAR(Synthetic Aperture Radar) and VIR FCC(Visible Infra-red, False Colour Composite). The techniques for the determination of the most informative SAR/VIR combinations in the triangular space diagram, as developed tv the author of the paper, are given and the results obtained are presented. The SAR alone, VIR alone and SAR/VIR FCC classification showed trends for gradual improvement of accuracy. Accuracy distribution pattern for individual classes could be explained closely related to SAR/VIR signature components in the process of the triangular synergistic training. Due to contribution of SAR signature in training samples, it was possible to isolate major terrain features such as cloud cover area and roughness target with acceptable spatial precision. It is anticipated that this research output could be used as a valuable reference for distribution trends of classification accuracy obtained by triangular channel space based training in synergistic application.

A Study on Optimizing the Clutter Rejection Capability for a High-Speed Scanning MTI-Pulse Radar (고속 스캔 MTI 펄스 레이더의 지형 클러터 제거 능력 최적화에 관한 연구)

  • Kim, Jong-Geon;Jang, Heon-Soon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.10
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    • pp.1077-1083
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    • 2009
  • To reject the Doppler frequency spectrum dispersion of clutter caused by high-speed antenna rotation of MTI radar system due to terrain characteristics, signal processing parameters(MTI filter constant, M/N detector ration, K-factor and offset of CFAR) are adjusted for the optimal elimination of the ground clutter. For this investigation, logging equipment is designed and utilized for the collection of classified ground clutter data. Test case is devised through Matlab simulation for the classified analysis and optimization of clutter rejection. Then indoor radar test and outside test in accordance with terrain characteristics are repeatedly performed for the verification of the test. This whole process is through the evolutional development model and repeated for the optimization. Final result is that ground-clutter rejection capability is 5.6 times(7.5 dB) better than that of existing radar system.

Binary Forecast of Asian Dust Days over South Korea in the Winter Season (남한지역 겨울철 황사출현일수에 대한 범주 예측모형 개발)

  • Sohn, Keon-Tae;Lee, Hyo-Jin;Kim, Seung-Bum
    • The Korean Journal of Applied Statistics
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    • v.24 no.3
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    • pp.535-546
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    • 2011
  • This study develops statistical models for the binary forecast of Asian dust days over South Korea in the winter season. For this study, we used three kinds of data; the rst one is the observed Asian dust days for a period of 31 years (1980 to 2010) as target values, the second one is four meteorological factors(near surface temperature, precipitation, snowfall, ground wind speed) in the source regions of Asian dust based on the NCEP reanalysis data and the third one is the large-scale climate indices. Four kinds of statistical models(multiple regression models, logistic regression models, decision trees, and support vector machines) are applied and compared based on skill scores(hit rate, probability of detection and false alarm rate).

One-Step-Ahead Control of Waveform and Detection Threshold for Optimal Target Tracking in Clutter (클러터 환경에서 최적의 표적 추적을 위한 파형 파라미터와 검출문턱 값의 One-Step-Ahead 제어)

  • Shin Han-Seop;Hong Sun-Mog
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.43 no.1 s.307
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    • pp.31-38
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    • 2006
  • In this paper, we consider one-step-ahead control of waveform parameters (pulse amplitudes and lengths, and FM sweep rate) as well as detection thresholds for optimal range and range-rate tracking in clutter. The optimal control of the combined parameter set minimizes a tracking performance index under a set of parameter constraints. The performance index includes the probability of track loss and a function of estimation error covariances. The track loss probability and the error covariance are predicted using a hybrid conditional average algorithm The effect of the false alarms and clutter interference is taken into account in the prediction. Tracking performance of the one-step-ahead control is presented for several examples and compared with a control strategy heuristically derived from a finite horizon optimization.

A Unknown Phishing Site Detection Method in the Interior Network Environment (내부 네트워크에서 알려지지 않은 피싱사이트 탐지방안)

  • Park, Jeonguk;Cho, Gihwan
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.25 no.2
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    • pp.313-320
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    • 2015
  • While various phishing attacks are getting to be increased in constant, their response methods still stay on the stage of responding after identifying an attack. To detect a phishing site ahead of an attack, a method has been suggested with utilizing the Referer header field of HTTP. However, it has a limitation to implement a traffic gathering system for each of prospective target hosts. This paper presents a unknown phishing site detection method in the Interior network environment. Whenever a user try to connect a phishing site, its traffic is pre-processed with considering of the characteristics of HTTP protocol and phishing site. The phishing site detection phase detects a suspicious site under phishing with analysing HTTP content. To validate the proposed method, some evaluations were conducted with 100 phishing URLs along with 100 normal URLs. The experimental results show that our method achieves higher phishing site detection rate than that of existing detection methods, as 66% detection rate for the phishing URLs, and 0% false negative rate for the normal URLs.

The Anti-Spoofing Methods Using Code Antiphase of Spoofing Signal (역 위상 코드를 이용한 기만신호 대응방법)

  • Kim, Taehee;Lee, Sanguk;Kim, Jaehoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.11
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    • pp.1044-1050
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    • 2013
  • This paper analyzes what is mitigated as spoofing attack using the U-Blox Receiver and GPS RF signal generator developed at ETRI. Generally the spoofing attack made the target receiver to be wrong navigation solution by providing false measurement of code and carrier. So we analyzed the impact of spoofing attack through the signal strength and navigation solution. In oder to test of effect of anti-spoofing signal, we consider the signal with antiphase code to spoofing signal and generated GPS normal signal and spoofing signal and anti-spoofing signal using GPS RF signal generator. This paper analyzed that the GPS receiver was responded to the spoofing attack according to code phase difference between spoofing and anti-spoofing signal. We confirmed that the spoofing signal was disappeared by anti-spoofing signal if code phase is an exact match.

Knowledge, Behavior and Beliefs Related to Cervical Cancer and Screening Among Turkish Women

  • Reis, Nesrin;Bebis, Hatice;Kose, Sevinc;Sis, Asli;Engin, Raziye;Yavan, Tulay
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1463-1470
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    • 2012
  • Objective: The aims of this study were to explore Turkish women's knowledge, behavior and beliefs related to cervical cancer and screening. Methods: The study was performed in two cities in the East of Turkey between September 2009 and April 2010, with a sampling group of 387 women. Data were collected by means of an interview form with the Health Belief Model Scale for Cervical Cancer and Pap Smear Test - Turkish Version. Results: Women in the research group were found to have poor knowledge, inadequate health behavior and low/medium level false beliefs regarding cervical cancer screening. There was relation between health beliefs and characteristics of women and particularly education (F = 10.80, p = 0.01). Similarly, it was found that Pap smear barriers were influenced by demographic characteristics and that women with low-level education (p = 0.001), divorced women (p = 0.05), women with low-income(p = 0.05), women who gave their first birth when they were 18 or younger (p = 0.05) and women not applying any contraceptive method at all (p = 0.01) were determined to have negative Pap smear barriers. Conclusions: Primarily the knowledge, attitudes and beliefs of women in the target group should be evaluated to increase their participation in cervical cancer screening and to prepare effective education strategies.