• Journal of KIISE:Computing Practices and Letters
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• v.15 no.11
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• pp.806-818
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• 2009

Since the invention of the integrated circuit (IC) in 1950s, semiconductor technology has undergone dramatic development up to these days. A complete semiconductor is manufactured through a diversity of processes. For better semiconductor productivity, fault detection and classification (FDC) has been rigorously studied for finding faults even before the processes are completed. For FDC, various kinds of sensors are attached in many semiconductor manufacturing devices, and sensor values are collected in a periodic manner. The collection of sensor values consists of sequences of real numbers, and hence is regarded as a kind of time-series data. In this paper, we propose an algorithm for detecting and clustering faults in semiconductor processes. The proposed algorithm is a modification of the existing anomaly detection algorithm dealing with symbolically-represented time-series. The contributions of this paper are: (1) showing that a modification of the existing anomaly detection algorithm dealing with general time-series could be used for semiconductor process data and (2) presenting experimental results for improving correctness of fault detection and clustering. As a result of our experiment, the proposed algorithm caused neither false positive nor false negative.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.237-241
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• 2012

Objective: Screening for colorectal cancer using guaiac-based fecal occult blood tests (gFOBT) is well established in Western populations, but is hampered by poor patient compliance due to the imposed dietary restrictions. Fecal immunochemical tests (FIT) do not require dietary restriction, but are more expensive than gFOBT and therefore restrict its use in developing countries in Asia. However, Asian diets being low in meat content may not require diet restriction for gFOBT to achieve equivalent results. The objective of this study was to evaluate and compare the validity and suitability of gFOBT and FIT or a combination of the two in screening for colorectal neoplasias without prior dietary restriction in an Asian population. Methods: Patients referred to the Endoscopic Unit for colonoscopy were recruited for the study. Stool samples were collected prior to bowel preparation, and tested for occult blood with both gFOBT and FIT. Dietary restriction was not imposed. To assess the validity of either tests or in combination to detect a neoplasm or cancer in the colon, their false positive rates, their sensitivity (true positive rate) and the specificity (true negative rate) were analyzed and compared. Results: One hundred and three patients were analysed. The sensitivity for picking up any neoplasia was 53% for FIT, 40% for gFOBT and 23.3% for the combination. The sensitivities for picking up only carcinoma were 77.8%, 66.7% and 55.5%, respectively. The specificity for excluding any neoplasia was 91.7% for FIT, 74% for gFOBT and 94.5% for a combination, whereas for excluding only carcinomas they were 84%, 73.4% and 93.6%. Of the 69 with normal colonoscopic findings, FOBT was positive in 4.3%, 23.2 %and 2.9% for FIT, gFOBT, or combination of tests respectively. Conclusion: FIT is the recommended method if we are to dispense with dietary restriction in our patients because of its relatively low-false positivity and better sensitivity and specificity rates.

• Journal of Yeungnam Medical Science
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• v.5 no.2
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• pp.47-52
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• 1988

The intradermal(ID) test has been widely used in Korea and several reports about the results of the ID test are known. We examined the egg of Clonorchis sinensis(C. s.) by ID test in 443, stool's egg-counting technique in 79 and direct smear(cellophane thick smear technique) in 1304 subjects. The results are as follows.: 1. The positive rate of C. s. was 3.8% out of 1304 persons. 2. The sensitivity of ID test was 82.1% out of 39 persons and, the specificity was 64.6% out of 404 persons. 3. The false positive of ID test 35.4% out of 404 persons and, the false negative was 17.9% out of 39 persons. Intradermal test is a rapid, sensitive and useful supplementary diagnostic tool for the detection of Clonorchiasis infection and must be used as screening test with direct smear of stool but cross reaction with other helminth infections and moderate false reaction are the main disadvantages in its practical application.

• Journal of Korean Neurosurgical Society
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• v.30 no.2
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• pp.186-193
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• 2001

Objectives : Trigeminal neuralgia and hemifacial spasm are caused by vascular compression of the REZ(root entry or exit zone) of the 5th and the 7th cranial nerve. Preoperative detection of neurovascular compression is essential for accurate diagnosis, appropriate treatment, and the good operative results. Three dimensional Fourier Transformation-Constructive Interference in Steady State(3DFT-CISS) images are known to give good contrast between CSF, nerve, and vessels. We applied a 3DFT-CISS imaging technique for the preoperative evaluation of patients with these diseases and estimated the diagnostic accuracy and usefulness of this study. Methods : A series of 71 patients with trigeminal neuralgia and hemifacial spasm were treated by microvascular decompression. Among them 34 patients with trigeminal neuralgia and 24 patients with hemifacial spasm had preoperative CISS images. We compared the radiologic finding with the operative finding, and analysed the diagnostic usefulness of 3DFT-CISS imaging. Results : The sensitivity of CISS images of detecting the neurovascular compression was 90.3% in trigeminal neuralgia and 100% in hemifacial spasm. There were one false-positive and three false-negative cases in trigeminal neuralgia, and one false-positive case in hemifacial spasm. The accuracy in diagnosing the causative vessel was 73.5% in trigeminal neuralgia and 83.3% in hemifacial spasm. Conclusion : CISS image is very useful diagnostic tool for preoperative evaluation of neurovascular compression in patients with trigeminal neuralgia and hemifacial spasm. No additional neuroradiologic examination other than CISS image and MRA is needed for preoperative evaluation of patients with trigeminal neuralgia and hemifacial spasm.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.294-302
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• 2022

Detection of fake news is a complex and a challenging task. Generation of fake news is very hard to stop, only steps to control its circulation may help in minimizing its impacts. Humans tend to believe in misleading false information. Researcher started with social media sites to categorize in terms of real or fake news. False information misleads any individual or an organization that may cause of big failure and any financial loss. Automatic system for detection of false information circulating on social media is an emerging area of research. It is gaining attention of both industry and academia since US presidential elections 2016. Fake news has negative and severe effects on individuals and organizations elongating its hostile effects on the society. Prediction of fake news in timely manner is important. This research focuses on detection of fake news spreaders. In this context, overall, 6 models are developed during this research, trained and tested with dataset of PAN 2020. Four approaches N-gram based; user statistics-based models are trained with different values of hyper parameters. Extensive grid search with cross validation is applied in each machine learning model. In N-gram based models, out of numerous machine learning models this research focused on better results yielding algorithms, assessed by deep reading of state-of-the-art related work in the field. For better accuracy, author aimed at developing models using Random Forest, Logistic Regression, SVM, and XGBoost. All four machine learning algorithms were trained with cross validated grid search hyper parameters. Advantages of this research over previous work is user statistics-based model and then ensemble learning model. Which were designed in a way to help classifying Twitter users as fake news spreader or not with highest reliability. User statistical model used 17 features, on the basis of which it categorized a Twitter user as malicious. New dataset based on predictions of machine learning models was constructed. And then Three techniques of simple mean, logistic regression and random forest in combination with ensemble model is applied. Logistic regression combined in ensemble model gave best training and testing results, achieving an accuracy of 72%.

• Journal of Trauma and Injury
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• v.19 no.2
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• pp.135-142
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• 2006

Purpose: We planned to determine the diagnostic capability of focused assessment with sonography for trauma (FAST) in cases of blunt abdominal injury (BAI). Methods: A retrospective analysis of FAST sheets was performed from April 2002 to December 2004. During the study period, 135 BAI patients were evaluated with FAST at the Emergency Department of Bundang CHA Hospital. Of this group, twenty-eight patients were excluded, leaving 107 patients for analysis. Abdomen CT (computerized tomography) or exploratory laparotomy confirmed the presence of hemoperitoneum. At the secondary survey, patients underwent a three-view FAST examination (LogicQ; General Electric, Waukesha, USA) by an emergency physician, followed within 2 hours by an abdomen CT or exploratory laparotomy. The FAST examination was considered positive if it demonstrated evidence of free intra-abdominal fluid. Results: There were 45 true-positive FAST examination, 57 true-negatives, 1 false-positive, and 4 false negatives (sensitivity 91.8%, specificity 98.3%, positive predictive value 97.8%, negative predictive value 93.4%). The area under the ROC curve was 0.951 for the FAST examination. Conclusion: FAST is a highly reliable method for screening patients suspected of having BAI for the presence or absence of hemoperitoneum.

• Journal of Korea Multimedia Society
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• v.13 no.7
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• pp.1088-1094
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• 2010

Image authentication algorithms have to discriminate forged contents in the various critical fields of military, medical services, digital documents. They must ensure perceptual invisibility and fragility against malicious attacks. It is desirable that watermarking algorithms support sufficient insertion capacity and blind feature. And, high reliable algorithms that can eliminate false-positive and false-negative errors are needed in the watermark extraction process. In this paper, we control coefficients of high frequency band in a DCT domain and compensate brightness histogram for high reliability. As a result, we found that the proposed algorithm guarantee various requirements such as perceptual invisibility with high PSNR values, fragility, high reliability and blind feature. In addition, experiment results show that the proposed algorithm can be used steganographic applications by sufficient capacity of watermark.

• Journal of Chest Surgery
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• v.26 no.3
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• pp.209-213
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• 1993

The pathogenesis of the primary spontaneous pneumothorax is the rupture of subpleural bleb or bullae and subsequent sudden collapse of the affected lung. Mostly, the bullae or blebs are present bilaterally, but detecting the number, size, and location of the causating foci by plain chest film is quite difficult . We have performed chest CT scans for detecting the bullous lesions in 33 cases of primary spontaneous pneumothorax, and compared the results with surgical findings.1. Seventy-four blebs were identified in the chest CT scan, and 100 blebs or bullae were detected surgically [ Sensitivity was 0.74 ].2. Diagnosis rate was 80% [40/50] at right upper lobe, 75.7% [28/37] at left upper lobe, 55.6% at right lower lobe, and 25.0% at left lower lobe, respectively.3. Blebs or bullae smaller than 1 cm of its diameter were detected by 57.1% [24/42] of sensitivity, and in the cases of size larger than 1 cm, it revealed 86.2% [50/58] of sensitivity respectively.4. Of the 45 cases, 7 cases were false negative [15.6%], most of these were ruptured or small size [< 0.5 cm]. 5. One case was false positive, which was irregular adhesion at the apex of the lung.6. We could detect blebs or bullae with preoperative CT scans in 84.4% [38/45] of total patients. In conclusion, chest CT scan is a very advantageous diagnostic tool for proper management and preventing recurrence of primary spontaneous pneumothorax patient.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.3
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• pp.19-25
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• 2017

Nowadays, networked computer systems play an increasingly important role in our society and its economy. They have become the targets of a wide array of malicious attacks that invariably turn into actual intrusions. This is the reason computer security has become an essential concern for network administrators. Recently, a number of Detection/Prevention System schemes have been proposed based on various technologies. However, the techniques, which have been applied in many systems, are useful only for the existing patterns of intrusion. Therefore, probe detection has become a major security protection technology to detection potential attacks. Probe detection needs to take into account a variety of factors ant the relationship between the various factors to reduce false negative & positive error. It is necessary to develop new technology of probe detection that can find new pattern of probe. In this paper, we propose an hybrid probe detection using Fuzzy Cognitive Map(FCM) and Self Adaptive Module(SAM) in dynamic environment such as Cloud and IoT. Also, in order to verify the proposed method, experiments about measuring detection rate in dynamic environments and possibility of countermeasure against intrusion were performed. From experimental results, decrease of false detection and the possibilities of countermeasures against intrusions were confirmed.

• Investigative Magnetic Resonance Imaging
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• v.26 no.2
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• pp.83-95
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• 2022

The purpose of this study was to establish and provide guidelines for the standardized acquisition and interpretation of diffusion-weighted magnetic resonance imaging (DW-MRI) to improve the image quality and reduce the variability of the results interpretation. The standardized protocol includes the use of high-resolution DW-MRI with advanced techniques and post-processing. The aim of the protocol is to increase the effectiveness of the medical image information exchange involved in the construction, activation, and exchange of clinical information for healthcare use. An organized interpretation form could make DW-MRIs' interpretation easier and more familiar. Herein, the authors briefly review the basic principles, optimized image acquisition, standardized interpretation guidelines, false negative and false positive cases of DW-MRI, and provide a standard interpretation form and examples of various cases to help users become more familiar with the DW-MRI.