• Title/Summary/Keyword: false positive

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A study on the false-positive reaction of Kastle-Meyer(KM) test and the application of KM reagent (Kastle-Meyer(KM) test의 위양성 반응과 시약 적용 방법에 관한 연구)

  • Kim, Chae-Lin;Kim, Chang-Yong;Kim, Min-Yeong;Yu, Je-Seol
    • Journal of the Korea Convergence Society
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    • v.11 no.10
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    • pp.139-146
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    • 2020
  • Kastle-Meyer (KM) test is one of presumptive tests used to detect latent blood in crime scenes. While this method is more sensitive than others, false positive reaction can be shown where blood does not exist. In this study, we tried to suggest a new application method to solve this problem. Reaction time and aspect of reaction of this new method was compared with two conventional methods in order to identify the effectiveness and identifiability. As a result, there was no statistically significant difference in sensitivity between the methods. In addition, in case of blood with a dilution ratio of 5000:1 or less, positive reaction showed immediately, making it easy to distinguish the reaction from false positive reaction. However, it became difficult to distinguish them with the reaction time as the dilution ratio increased, and this phenomenon could be supplemented observing aspect of the reaction when using the new method. Therefore, this study suggested a new method for KM test that can be used more accurately in the field.

Sialolithiasis Mimicking Metastatic Thyroid Cancer (갑상선암 전이병소로 오인된 타석증 증례)

  • Jeong, Hwan-Jeong;Bom, Hee-Seung;Song, Ho-Cheon;Min, Jung-Jun;Kim, Seung-Min;Kim, Ji-Yeul
    • The Korean Journal of Nuclear Medicine
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    • v.34 no.1
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    • pp.94-98
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    • 2000
  • We report a false positive case of I-131 scan due to a sialolithiasis in right submandibular gland. I-131 images showed not only remnant thyroid tissues and functional metastases in the anterior neck but also a hot uptake near right submandibular gland. We confirmed the sialolithiasis by radiologic studies. Sialolithiasis should be regarded as a false positive cause when I-131 scan shows a hot spot near salivary bed.

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An Indexing Method to Prevent Attacks based on Frequency in Database as a Service (서비스로의 데이터베이스에서 빈도수 기반의 추론공격 방지를 위한 인덱싱 기법)

  • Jung, Kang-Soo;Park, Seog
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.8
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    • pp.878-882
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    • 2010
  • DaaS model that surrogates their data has a problem of privacy leakage by service provider. In this paper, we analyze inference attack that can occur on encrypted data that consist of multiple column through index, and we suggest b-anonymity to protect data against inference attack. We use R+-tree technique to minimize false-positive that can happen when we use an index for efficiency of data processing.

False Positive SOD Activity of Bifidobacterium spp. Grown in MRS Medium

  • Chang, Woo-Suk;So, Jae-Seong
    • Journal of Microbiology and Biotechnology
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    • v.8 no.4
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    • pp.305-309
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    • 1998
  • The superoxide dismutase (SOD) activity of seven Bifidobacterium spp. strains was examined by an indirect SOD assay method. Some Bifidobacterium spp. showed significant levels of SOD activity. However, we could not observe any significant differences between anaerobic and aerobic cultures. Furthermore, although several Bifidobacterium spp. exhibited some degree of tolerance to paraquat which produces superoxide radicals, the apparent SOD activity of these strains was not correlated with their resistance to paraquat. In addition, when we added increasing amounts of manganese or iron to MRS medium which had been prepared without either of the metal ions, the apparent SOD activity of cell free extracts (CFEs) was increased with increasing concentration of both metal ions. To our surprise, the heat-denatured CFEs also showed nearly identical correlative patterns. Based on these results, the apparent SOD activity was likely due to a nonenzymatic dismutation. These results strongly suggest that high concentration of divalent metal ions ($Mn^{2+}$, $Fe^{2+}$) in MRS medium result in nonenzymatic dismutation which can lead to false positive SOD activities in Bifidobacerium spp.

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A Criterion on Profiling for Anomaly Detection (이상행위 탐지를 위한 프로파일링 기준)

  • 조혁현;정희택;김민수;노봉남
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.3
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    • pp.544-551
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    • 2003
  • Internet as being generalized, intrusion detection system is needed to protect computer system from intrusions synthetically. We propose a criterion on profiling for intrusion detection system using anomaly detection. We present the cause of false positive on profiling and propose anomaly method to control this. Finally, we propose similarity function to decide whether anomaly action or not for user pattern using pattern database.

The Implemetation of Real-time Broadcast Synchronizing System Using Audio Watermark (오디오 워터마크를 이용한 실시간 방송동기화시스템의 구현)

  • Shin Dong-Hwan;Kim Jong-Weon
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.54 no.12
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    • pp.716-722
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    • 2005
  • In this paper, we propose the audio watermarking algorithm based on the critical band of HAS(human auditory system) without audibly affecting the quality of the watermarked audio and implement the detecting algorithm on the BSS(broadcast synchronizing system) for testing the proposed algorithm. According to the audio quality test, the SNR(signal to noise ratio) of the watermarked audio objectively is 66dB above. In the robustness test, the proposed algorithm can detect the watermark more than $90\%$ from various compression(MP3, AAC), A/D and D/A conversions, sampling rate conversions and especially asynchronizing attacks. The BSS automatically switches the programs between the key station and the local station in broadcasting system. The result of reliability test of implemented system by using the real broadcasting audio has no false positive error during 30 days. Because of detecting once processing per 0.5 second, we can judge that the false positive error does not occur.

A Cytopathologic Analysis of Percutaneous Transthoracic Needle Aspiration Cytology - A Six-year Correlation Study in 322 Cases - (폐의 경흉 세침흡인 세포검사 322예의 분석)

  • Kim, Sook;Kim, Dong-Won;Jin, So-Young;Lee, Dong-Wha
    • The Korean Journal of Cytopathology
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    • v.6 no.2
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    • pp.140-147
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    • 1995
  • In a six-year period (1988. 5-1994. 4), fine needle aspiration cytology(FNAC) of 322 pulmonary lesions from 296 patients were performed at Soonchunhyang University Hospital. Of these 322, malignancy was diagnosed cytologically in 139(43.2%), suspicious malignancy in 7(2.2%), negative in 164(50.8%), and insufficient material in 12(3.8%). Malignant lesions consisted of 54 cases of adenocarcinoma, 50 cases of squamous cell carcinoma, 18 cases of small cell carcinoma. They were verified by histologic examination in 70 cases. There were 2(0.6%) false positive cases due to florid bronchoalveolar hyperplasia and atypical bronchial epithelial cells associated with granulomatous lesion. The overall accuracy rate was 90%, the sensitivity 84.3% and the specificity 94.7%.

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Cloud Storage Security Deduplication Scheme Based on Dynamic Bloom Filter

  • Yan, Xi-ai;Shi, Wei-qi;Tian, Hua
    • Journal of Information Processing Systems
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    • v.15 no.6
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    • pp.1265-1276
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    • 2019
  • Data deduplication is a common method to improve cloud storage efficiency and save network communication bandwidth, but it also brings a series of problems such as privacy disclosure and dictionary attacks. This paper proposes a secure deduplication scheme for cloud storage based on Bloom filter, and dynamically extends the standard Bloom filter. A public dynamic Bloom filter array (PDBFA) is constructed, which improves the efficiency of ownership proof, realizes the fast detection of duplicate data blocks and reduces the false positive rate of the system. In addition, in the process of file encryption and upload, the convergent key is encrypted twice, which can effectively prevent violent dictionary attacks. The experimental results show that the PDBFA scheme has the characteristics of low computational overhead and low false positive rate.

Automatic detection of pulmonary nodules in X-ray chest images (폐의 X선 영상에서의 노쥴 자동 탐지 기법)

  • Seong, Won;Park, Jong-Won
    • Proceedings of the Korea Information Processing Society Conference
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    • 2002.04a
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    • pp.767-770
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    • 2002
  • 일반적으로 방사선 의사들(radialogists)이 폐 노쥴(pulmonary nodule)을 탐지하는 데는 실제적으로 30%의 실패율을 가진다고 알려져 있다. 만약 자동화된 시스템이 체스트 영상에서 의심스런 노쥴들의 위치들을 방사선 의사에게 알려줄 수 있다면 잘못 판단되는 노쥴들의 수를 잠재적으로 줄일 수 있다. 우리는 형태학적 필터들(morphological filters)과 두가지 특징-추출(feature-extraction) 기술들을 포함하는 컴퓨터 자동 처리 시스템을 구현하였다. 본 시스템에서는 첫째로 형태학적 필터(morphological filtering) 처리를 행한다. 이 과정은 원래의 영상에 침식(erosion)과 확장 (dilation)을 연이어서 행하는 것으로 처리가 어려운 X 선 영상을 좀 더 다루기 쉬운 상태로 바꿔주는 역할을 하게 된다. 둘째는 일차적으로 노쥴로서 컴퓨터에 선택된 의심 부분에 가해주는 특징-추출 테스트로서 이 작용은 노쥴로 감지되었으나 실제로는 노쥴이 아닌 경우인 false-positive 갑지들을 줄이기 위해서 사용된다. 그리하여 본 시스템은 노쥴의 정확한 판독이 어려운 폐의 X 선 영상에 적용되어 false-positive 들을 효과적으로 줄임으로써 보다 효율적인 폐 노쥴의 탐지를 가능하게 하였다.

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Blind Watermarking Scheme Using Singular Vectors Based on DWT/RDWT/SVD

  • Luong, Ngoc Thuy Dung;Sohn, Won
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2015.11a
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    • pp.173-175
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    • 2015
  • We proposed a blind watermarking scheme using singular vectors based on Discrete Wavelet Transform (DWT) and Redundant Discrete Wavelet Transform (RDWT) combined with Singular Value Decomposition (SVD) for copyright protection application. We replaced the 1st left and right singular vectors decomposed from cover image with the corresponding ones from watermark image to overcome the false-positive problem in current watermark systems using SVD. The proposed scheme realizes the watermarking system without a false positive problem, and shows high fidelity and robustness.

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