• Title/Summary/Keyword: False target

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Performance Prediction of the MHT Algorithm for Tracking under Cluttered Environments (클러터 환경에서 표적 추적을 위한 다중 가설 추적 알고리듬의 성능 예측)

  • 정영헌
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.41 no.4
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    • pp.13-20
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    • 2004
  • In this paper, we developed a method for predicting the tracking performance of the multiple hypothesis tracking (MHT) algorithm. The MHT algerithm is known to be a measurement-oriented optimal Bayesian approach and is superior to any other tracking filters because it takes into account the events that the measurements can be originated from new targets and false alarms as well as interesting targets. In the MHT algorithm, a number of candidate hypotheses are generated and evaluated later as more data are received. The probability of each candidate hypotheses is approximately evaluated by using the hybrid conditional average approach (HYCA). We performed numerical experiments to show the validity of our performance prediction.

Cooperative Spectrum Sensing for Cognitive Radio Systems with Energy Harvesting Capability (에너지 수집 기능이 있는 인지 무선 시스템의 협력 스펙트럼 센싱 기법)

  • Park, Sung-Soo;Lee, Seok-Won;Bang, Keuk-Joon;Hong, Dae-Sik
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.3
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    • pp.8-13
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    • 2012
  • In this paper, we investigate cooperative spectrum sensing scheme for sensor network-aided cognitive radio systems with energy harvesting capability. In the proposed model, each sensor node harvests ambient energy from environment such as solar, wind, mechanical vibration, or thermoelectric effect. We propose adaptive cooperative spectrum sensing scheme in which each sensor node adaptively carries out energy detection depending on the residual energy in its energy storage and then conveys the sensing result to the fusion center. From simulation results, we show that the proposed scheme minimizes the false alarm probability for given target detection probability by adjusting the number of samples for energy detector.

Weighted Collaborative Representation and Sparse Difference-Based Hyperspectral Anomaly Detection

  • Wang, Qianghui;Hua, Wenshen;Huang, Fuyu;Zhang, Yan;Yan, Yang
    • Current Optics and Photonics
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    • v.4 no.3
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    • pp.210-220
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    • 2020
  • Aiming at the problem that the Local Sparse Difference Index algorithm has low accuracy and low efficiency when detecting target anomalies in a hyperspectral image, this paper proposes a Weighted Collaborative Representation and Sparse Difference-Based Hyperspectral Anomaly Detection algorithm, to improve detection accuracy for a hyperspectral image. First, the band subspace is divided according to the band correlation coefficient, which avoids the situation in which there are multiple solutions of the sparse coefficient vector caused by too many bands. Then, the appropriate double-window model is selected, and the background dictionary constructed and weighted according to Euclidean distance, which reduces the influence of mixing anomalous components of the background on the solution of the sparse coefficient vector. Finally, the sparse coefficient vector is solved by the collaborative representation method, and the sparse difference index is calculated to complete the anomaly detection. To prove the effectiveness, the proposed algorithm is compared with the RX, LRX, and LSD algorithms in simulating and analyzing two AVIRIS hyperspectral images. The results show that the proposed algorithm has higher accuracy and a lower false-alarm rate, and yields better results.

A Study on Preprocessing Method for Effective Semantic-based Similarity Measures using Approximate Matching Algorithm (의미적 유사성의 효과적 탐지를 위한 데이터 전처리 연구)

  • Kang, Hari;Jeong, Doowon;Lee, Sangjin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.25 no.3
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    • pp.595-602
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    • 2015
  • One of the challenges of the digital forensics is how to handle certain amounts of data efficiently. Although reliable and various approximate matching algorithms have been presented to quickly identify similarities between digital objects, its practical effectiveness to identify the semantic similarity is low because of frequent false positives. To solve this problem, we suggest adding a pre-processing of the approximate matching target dataset to increase matching accuracy while maintaining the reliability of the approximate matching algorithm. To verify the effectiveness, we experimented with two datasets of eml and hwp using sdhash in order to identify the semantic similarity.

Real-Time Object Recognition for Children Education Applications based on Augmented Reality (증강현실 기반 아동 학습 어플리케이션을 위한 실시간 영상 인식)

  • Park, Kang-Kyu;Yi, Kang
    • Journal of Korea Multimedia Society
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    • v.20 no.1
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    • pp.17-31
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    • 2017
  • The aim of the paper is to present an object recognition method toward augmented reality system that utilizes existing education instruments that was designed without any consideration on image processing and recognition. The light reflection, sizes, shapes, and color range of the existing target education instruments are major hurdles to our object recognition. In addition, the real-time performance requirements on embedded devices and user experience constraints for children users are quite challenging issues to be solved for our image processing and object recognition approach. In order to meet these requirements we employed a method cascading light-weight weak classification methods that are complimentary each other to make a resultant complicated and highly accurate object classifier toward practically reasonable precision ratio. We implemented the proposed method and tested the performance by video with more than 11,700 frames of actual playing scenario. The experimental result showed 0.54% miss ratio and 1.35% false hit ratio.

Study on Ship Detection Using SAR Dual-polarization Data: ENVISAT ASAR AP Mode

  • Yang, Chan-Su;Ouchi, Kazuo
    • Korean Journal of Remote Sensing
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    • v.24 no.5
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    • pp.445-452
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    • 2008
  • Preliminary results are reported on ship detection using coherence images computed from cross-correlating images of multi-look-processed dual-polarization data (HH and HV) of ENVISAT ASAR. The traditional techniques of ship detection by radars such as CFAR (Constant False Alarm Rate) rely on the amplitude data, and therefore the detection tends to become difficult when the amplitudes of ships images are at similar level as the mean amplitude of surrounding sea clutter. The proposed method utilizes the property that the multi-look images of ships are correlated with each other. Because the inter-look images of sea surface are covered by uncorrelated speckle, cross-correlation of multi-look images yields the different degrees of coherence between the images and water. In this paper, the polarimetric information of ships, land and intertidal zone are first compared based on the cross-correlation between HH and HV images, In the next step, we examine the technique when the dual-polarization data are split into two multi-look images, It was shown that the inter-look cross-correlation method could be applicable in the performance improvement of small ship detection and the land masking, It was also found that a simple combination of coherence images from each co-polarised (HH) inter-look and cross-polarised (HV) inter-look data can provide much higher target-detection possibilities.

Setting the Current Air Quality Concentration Using the National Atmosphere Measurement Network

  • CHO, Dong-Myung;LEE, Ju-Yeon;KWON, Lee-Seung;KIM, Su-Hye;KWON, Woo-Taeg
    • Journal of Wellbeing Management and Applied Psychology
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    • v.4 no.3
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    • pp.23-33
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    • 2021
  • Purpose: In the course of the domestic environmental impact assessment, the current status survey was improperly conducted, and the issue of false and inaccurate environmental impact assessment reports has been raised several times recently through media reports. Research design, data and methodology: There is a continuous demand for improvement measures for the current status measurement method, such as having difficulties in securing a normal measurement date in consideration of equipment operation and rainfall days in the field. Results: In addition, in order to grasp the general air quality status of the evaluation target area, it is necessary to check the various current status concentrations by season and time series per year. However, there is a problem that is currently being carried out based on limited results such as measurement for 1 day or 3 days. Conclusions: Therefore, in this study, based on the national atmospheric measurement network, an inverse distance weighted (IDW) interpolation method was applied to calculate the current state concentration. This study suggested a method to use it in preparing the air quality item in the environmental impact assessment report.

The Influence of Change Prevalence on Visual Short-Term Memory-Based Change Detection Performance (변화출현확률이 시각단기기억 기반 변화탐지 수행에 미치는 영향)

  • Son, Han-Gyeol;Hyun, Joo-Seok
    • Korean Journal of Cognitive Science
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    • v.32 no.3
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    • pp.117-139
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    • 2021
  • The way of change detection in which presence of a different item is determined between memory and test arrays with a brief in-between time interval resembles how visual search is done considering that the different item is searched upon the onset of a test array being compared against the items in memory. According to the resemblance, the present study examined whether varying the probability of change occurrence in a visual short-term memory-based change detection task can influence the aspect of response-decision making (i.e., change prevalence effect). The simple-feature change detection task in the study consisted of a set of four colored boxes followed by another set of four colored boxes between which the participants determined presence or absence of a color change from one box to the other. The change prevalence was varied to 20, 50, or 80% in terms of change occurrences in total trials, and their change detection errors, detection sensitivity, and their subsequent RTs were analyzed. The analyses revealed that as the change prevalence increased, false alarms became more frequent while misses became less frequent, along with delayed correct-rejection responses. The observed change prevalence effect looks very similar to the target prevalence effect varying according to probability of target occurrence in visual search tasks, indicating that the background principles deriving these two effects may resemble each other.

Development and Evaluation of a Next-Generation Sequencing Panel for the Multiple Detection and Identification of Pathogens in Fermented Foods

  • Dong-Geun Park;Eun-Su Ha;Byungcheol Kang;Iseul Choi;Jeong-Eun Kwak;Jinho Choi;Jeongwoong Park;Woojung Lee;Seung Hwan Kim;Soon Han Kim;Ju-Hoon Lee
    • Journal of Microbiology and Biotechnology
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    • v.33 no.1
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    • pp.83-95
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    • 2023
  • These days, bacterial detection methods have some limitations in sensitivity, specificity, and multiple detection. To overcome these, novel detection and identification method is necessary to be developed. Recently, NGS panel method has been suggested to screen, detect, and even identify specific foodborne pathogens in one reaction. In this study, new NGS panel primer sets were developed to target 13 specific virulence factor genes from five types of pathogenic Escherichia coli, Listeria monocytogenes, and Salmonella enterica serovar Typhimurium, respectively. Evaluation of the primer sets using singleplex PCR, crosscheck PCR and multiplex PCR revealed high specificity and selectivity without interference of primers or genomic DNAs. Subsequent NGS panel analysis with six artificially contaminated food samples using those primer sets showed that all target genes were multi-detected in one reaction at 108-105 CFU of target strains. However, a few false-positive results were shown at 106-105 CFU. To validate this NGS panel analysis, three sets of qPCR analyses were independently performed with the same contaminated food samples, showing the similar specificity and selectivity for detection and identification. While this NGS panel still has some issues for detection and identification of specific foodborne pathogens, it has much more advantages, especially multiple detection and identification in one reaction, and it could be improved by further optimized NGS panel primer sets and even by application of a new real-time NGS sequencing technology. Therefore, this study suggests the efficiency and usability of NGS panel for rapid determination of origin strain in various foodborne outbreaks in one reaction.

Detection of Recombinant Marker DNA in Genetically Modified Glyphosate- Tolerant Soybean and Use in Environmental Risk Assessment

  • Kim, Young-Tae;Park, Byoung-Keun;Hwang, Eui-Il;Yim, Nam-Hui;Lee, Sang-Han;Kim, Sung-Uk
    • Journal of Microbiology and Biotechnology
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    • v.14 no.2
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    • pp.390-394
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    • 2004
  • The genetically modified glyphosate-tolerant soybean contains the following introduced DNA sequences: the EPSPS (5-enol-pyruvylshikimate-3-phosphate synthase) gene from Agrobacterium sp. strain CP4, the 35S promoter from the cauliflower mosaic virus, and the NOS terminator from Agrobacterium tumefaciens. In the present study, detection of these introduced DNAs was performed by amplification using the polymerase chain reaction (PCR). A multiplex PCR method was also applied to prevent false positive results. When primers for 35S promoter, nos3', CTP(chloroplast transit peptide), and CP4 EPSPS (EPSPS from Agrobacterium sp. CP4) were used, positive results were obtained in PCR reactions using DNA from genetically modified glyphosate-tolerant soybeans. There were no false positive results when using DNA from non-genetically modified soybeans. The CP4 EPSPS gene was detected when less than 125 pg glyphosate-tolerant soybean DNA was amplified. Lectin Lel and psb A were amplified from both non-genetically modified and genetically modified glyphosate-tolerant soybean DNA. Multiplex PCR was performed using different primer sets for actin Sacl, 35S promoter and CP4 EPSPS. The actin gene was detectable in both non-genetically modified and glyphosate-tolerant soybeans as a constant endogenous gene. Target DNAs for the 35S promoter, and CP4 EPSPS were detected in samples containing 0.01-0.1% glyphosate-tolerant soybean, although there were variations depending on primers by multiplex PCR. Soybean seeds from five plants of non-genetically modified soybean were co-cultivated for six months with those of genetically modified soybean, and they were analyzed by PCR. As a result, they were not positive for 35S promoter, nos3' or CP4 EPSPS. Therefore, these results suggest there was no natural crossing of genes between glyphosate-tolerant and non-genetically modified soybean during co-cultivation, which indicates that gene transfer between these plants is unlikely to occur in nature.