• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.109-116
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• 2001

An integrated damage identification system (IDIS) and system identification (SID) technique using modal information to detect damage in structures is presented. The objective is to detect damages in cracked model plate-girder without baseline modal parameters. The theory of damage localization and system identification is outlined. Experiments on a model plate-girder was described and a baseline model representing the experimental modal characteristics of the model plate-girder is updated using the system identification technique. Finally, damage inflicted in the model plate-girder is predicted using the IDIS software.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.9
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• pp.884-891
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• 2009

This study investigates some of swarm intelligence algorithms to tackle a traditional damage detection problem having stiffness degradation or damage in mechanical structures. Particle swarm(PSO) and ant colony optimization(ACO) methods have been exploited for localizing and estimating the location and extent damages in a structure. Both PSO and ACO are population-based, stochastic algorithms that have been developed from the underlying concept of swarm intelligence and search heuristic. A finite element (FE) model updating is implemented to minimize the difference in a set of natural frequencies between measured and baseline vibration data. Stiffness loss of certain elements is considered to simulate structural damages in the FE model. It is numerically shown that PSO and ACO algorithms successfully completed the optimization process of model updating in locating unknown damages in a truss structure.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.377-380
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• 1996

The purpose of this paper is to improve the P-wave detection capacity using wavelet transform. The first procedure is to remove baseline drift using the median filter. The second procedure is to cancel ECG's QRS-T complex with ECG's QRS-T complex templete to get P-wave candidate. Before we cancelled out the QRS-T complex, we estimated the best matching between templete and QRS-T complex to minimize the error. Then, Harr wavelet was used to eleminate the high frequency noise of ECG wave form cancelled the QRS-T complex. Finally, P-wave was discriminated and confirmed by threshold value. By using this method, We can got the around 95.1% P-wave detection.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4684-4705
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• 2019

Collaborative filtering recommender systems are vulnerable to shilling attacks in which malicious users may inject biased profiles to promote or demote a particular item being recommended. To tackle this problem, many robust collaborative recommendation methods have been presented. Unfortunately, the robustness of most methods is improved at the expense of prediction accuracy. In this paper, we construct a robust Bayesian probabilistic matrix factorization model for collaborative filtering recommender systems by incorporating the detection of user anomaly rating behaviors. We first detect the anomaly rating behaviors of users by the modified K-means algorithm and target item identification method to generate an indicator matrix of attack users. Then we incorporate the indicator matrix of attack users to construct a robust Bayesian probabilistic matrix factorization model and based on which a robust collaborative recommendation algorithm is devised. The experimental results on the MovieLens and Netflix datasets show that our model can significantly improve the robustness and recommendation accuracy compared with three baseline methods.

• Smart Structures and Systems
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• v.24 no.5
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• pp.597-606
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• 2019

Damage detection based on dynamic characteristics of a structure is one of important roles in structural damage identification. It is difficult to detect local structural damage using traditional dynamic experimental methods due to a limited number of sensors used in an experiment. In this work, a non-contact test stand of fan blades is established, and a full-field noncontact test method, combined with three-dimensional digital image correlation, Bayesian operational modal analysis, and damage indices, is used to detect local damage of a fan blade under ambient excitation without use of baseline information before structural damage. The methodology is applied to detect invisible local damage on the fan blade. Such a method has a seemingly high potential as an alternative to detect local damage of blades with complex high-precision surfaces under extreme working conditions because it is a noncontact test method and can be used under ambient excitation without human participation.

• KSBB Journal
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• v.22 no.6
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• pp.443-446
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• 2007

A prognostic indicator of coronary heart disease, C-reactive protein, was tried to be determined by a batch-type quartz crystal microbalance immunosensor. The sensor was operated by direct-binding mode and the optimum concentration for the corresponding antibody for immobilization was $50{\mu}g/ml$. The reaction buffer for the system was 0.1 M sodium phosphate (pH 7.0) and system operation was performed in the order of baseline stabilization, analyte addition and measurement, and regeneration of the sensor chip with 10 mM NaOH. When plotted in double-logarithmic scale, the sensor showed a linear detection range of 0.27-106.00 nM for rat C-reactive protein with the limit of detection of 0.53 nM. It also showed a good reusability.

• Acute and Critical Care
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• v.33 no.4
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• pp.238-245
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• 2018

Background: Infection by multidrug-resistant (MDR) pathogens leads to poor patient outcomes in intensive care units (ICUs). Contact precautions are necessary to reduce the transmission of MDR pathogens. However, the importance of the surrounding environment is not well known. We studied the effects of ICU relocation on MDR respiratory pathogen detection rates and patient outcomes. Methods: Patients admitted to the ICU before and after the relocation were retrospectively analyzed. Baseline patient characteristics, types of respiratory pathogens detected, antibiotics used, and patient outcomes were measured. Results: A total of 463 adult patients admitted to the ICU, 4 months before and after the relocation, were included. Of them, 234 were admitted to the ICU before the relocation and 229 afterward. Baseline characteristics, including age, sex, and underlying comorbidities, did not differ between the two groups. After the relocation, the incidence rate of MDR respiratory pathogen detection decreased from 90.0 to 68.8 cases per 1,000 patient-days, but that difference was statistically insignificant. The use of colistin was significantly reduced from 53.5 days (95% confidence interval [CI], 20.3 to 86.7 days) to 18.7 days (95% CI, 5.6 to 31.7 days). Furthermore, the duration of hospital stay was significantly reduced from a median of 29 days (interquartile range [IQR], 14 to 50 days) to 21 days (IQR, 11 to 39 days). Conclusions: Incidence rates of MDR respiratory pathogen detection were not significantly different before and after ICU relocation. However, ICU relocation could be helpful in reducing the use of antibiotics against MDR pathogens and improving patient outcomes.

• Journal of Ginseng Research
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• v.43 no.4
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• pp.684-691
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• 2019

Background: We have reported that defective nef and gag genes are induced in HIV-1-infected patients treated with Korean Red Ginseng (KRG). Methods: To investigate whether KRG treatment and highly active antiretroviral therapy (HAART) affect genetic defects in the pol gene, we amplified and sequenced a partial pol gene (p-pol) containing the integrase portion (1.2 kb) by nested PCR with sequential peripheral blood mononuclear cells over 20 years and compared it with those patients at baseline, in control patients, those taking ginseng-based combination therapy (GCT; KRG plus combinational antiretroviral therapy) and HAART alone. We also compared our findings to look for the full-length pol gene (pol) (3.0-kb) Results: Twenty-patients infected with subtype B were treated with KRG for $116{\pm}58months$ in the absence of HAART. Internal deletion in the pol gene (${\Delta}pol$) was significantly higher in the KRG group (11.9%) than in the control group and at baseline; its detection was significantly inhibited during GCT as much as during HAART. In addition, the ${\Delta}pol$ in p-pol significantly depended on the duration of KRG treatment. In pol, the proportion of ${\Delta}pol$ was significantly higher in the KRG group (38.7%) than in the control group, and it was significantly inhibited during GCT and HAART. In contrast, the proportion of stop codon appeared not to be affected by KRG treatment. The PCR success rate was significantly decreased with longer GCT. Conclusion: The proportion of ${\Delta}pol$ depends on template size as well as KRG treatment. HAART decreases the detection of ${\Delta}pol$.

• Journal of Preventive Medicine and Public Health
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• v.55 no.3
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• pp.273-279
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• 2022

Objectives: The aim of this study was to present the baseline results of a pilot project conducted to evaluate the effectiveness of lung cancer screening using low-dose chest computed tomography (CT) in regions with excessive radon levels in the Republic of Kazakhstan. Methods: In total, 3671 participants were screened by low-dose chest CT. Current, former, and never-smokers who resided in regions with elevated levels of radon in drinking water sources and indoor air, aged between 40 and 75 with no history of any cancer, and weighing less than 140 kg were included in the study. All lung nodules were categorized according to the American College of Radiology Lung Imaging Reporting and Data System (Lung-RADS 1.0). Results: Overall, 614 (16.7%) participants had positive baseline CT findings (Lung-RADS categories 3 and 4). Seventy-four cancers were detected, yielding an overall cancer detection rate of 2.0%, with 10.8% (8/74) stage I and a predominance of stage III (59.4%; 44/74). Women never-smokers and men current smokers had the highest cancer detection rates, at 2.9% (12/412) and 6.1% (12/196), respectively. Compared to never-smokers, higher odds ratios (ORs) of lung cancer detection were found in smokers (OR,2.48; 95% confidence interval [CI], 1.52 to 4.05, p<0.001) and former smokers (OR, 2.32; 95% CI, 1.06 to 5.06, p=0.003). The most common histologic type of cancer was adenocarcinoma (58.1%). Conclusions: Implementation of low-dose CT screening for lung cancer in regions with elevated radon levels is an effective method for both smokers and never-smokers.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.5120-5142
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• 2018

Social media enables customers to share their views, opinions and experiences as product reviews. These product reviews facilitate customers in buying quality products. Due to the significance of online reviews, fake reviews, commonly known as spam reviews are generated to mislead the potential customers in decision-making. To cater this issue, review spam detection has become an active research area. Existing studies carried out for review spam detection have exploited feature engineering approach; however limited number of features are considered. This paper proposes a Feature-Centric Model for Review Spam Detection (FMRSD) to detect spam reviews. The proposed model examines a wide range of feature sets including ratings, sentiments, content, and users. The experimentation reveals that the proposed technique outperforms the baseline and provides better results.