• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.751-754
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• 2002

This paper introduces a way to realize biquadratic transfer functions using Operational Amplifiers (OAs) and Operational Transconductance Amplifiers (OTAs). The basic circuit configuration is constructed with two OAs and five OTAs. It is shown that low-pass, band-pass, high-pass, band-stop and all-pass transfer functions can be realized by suitably choosing the input terminals. And the circuit parameters can also be set by the transconductance gains of the OTAs independently. An example is given together with simulated results by PSPICE.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.232-233
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• 2003

Quasi-phase-match (QPM) can be realized by means of one-dimensional spatial modulation of second-order nonlinear susceptibility and has advantages over the conventional bulk phase-matching method because QPM can not only utilize the largest component of second-order nonlinear susceptibility tensor, but also can circumvent walk-off effect. (omitted)

• 한국가스학회:학술대회논문집
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• 2005.10a
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• pp.5-11
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• 2005

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.414-421
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• 1999

Helicobacter pylori were found to be resistant to azide but sensitive to vanadate, suggesting that defect in the P-type ATPase activity rather than F-type ATPase would be lethal to cell survival or growth. To elucidate the relationship between this enzyme inhibition and H. pylori death, we determined the effect of omeprazole (OMP) plus vanadate on enzyme activity and cell growth. The minimum inhibitory concentration (MIC; ca. 0.8$\mu$mol/disk) of vanadate for H. pylori growth was lowered over l0-fold with the aid of OMP, whereby its inhibitory potential toward the P-type ATPase activity was diametrically increased. Alternatively, we found that this enzyme activity was essential for active transport in H. pylori. From these observations, we strongly suggest that the immediate cause of the growth inhibition of H. pylori cells with OMP and/or vanadate might be defective in the cell's active transport due to the lack of P-type ATPase activity. From the spectral data with circular dichroism (CD) spectroscopy, we found that activated OMP (OAS) at concentration below MIC did not disrupt helical structures of membrane proteins. Separately, we determined the cytopathic effect of OAS by SDS-PAGE, indicating the change in the production of cytoplasmic protein but not cell membrane.

• Journal of Oral Medicine and Pain
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• v.37 no.4
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• pp.213-219
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• 2012

Oral appliances are a primary treatment option for snoring and mild to moderate obstructive sleep apnea (OSA) and are considered as an alternative for patients with severe OSA who have failed continuous positive airway pressure (CPAP) or upper airway surgery. But it is true that OAs have varying degrees of effectiveness depending on different oral appliances and the efficacy of OAs are established in some but not all patients. New oral appliance, which is one of Adjustable Anterior Positioners, was developed by Dept of Oral Medicine, Dental School, Dankook University. This is a report for treating severe OSA patient with a failure of previous uvulopalatopharyngoplasty using a new Adjustable Anterior Positioner, followed by significant success of controlling OSA.

• Journal of Oral Medicine and Pain
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• v.43 no.3
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• pp.61-69
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• 2018

Obstructive sleep apnea (OSA) is a relatively common, but greatly underdiagnosed sleep-related breathing disorder, characterized by recurrent collapse of the upper airway during sleep. OSA has been associated with a variety of cardiometabolic disease, such as hypertension, coronary artery disease, cardiac arrhythmia, cerebrovascular disease and metabolic dysfunction. Neurocognitive impairment, including excessive daytime sleepiness, increased risk of motor vehicle accidents, is also related to OSA. Sleep fragmentation and related arousals during sleep lead to intermittent hypoxia, sympathetic activation, oxidative stress, systemic inflammation and metabolic dysregulation which provide biological plausibility to this pathologic mechanism. Extensive studies demonstrated that OSA is a modifiable risk factor for the above mentioned diseases and oral appliances (OAs), although continuous positive air pressure (CPAP) is a first-line therapy of OSA, are not inferior to CPAP at least in mild OSA, and may be an alternative to CPAP in CPAP-intolerant subjects with OSA. The goal of this article is to provide a current knowledge of pathologic link between OSA and cardiovascular disease, focusing on intermittent hypoxia, sympathetic activation, oxidative stress and metabolic dysregulation. Then, previous epidemiologic studies will be reviewed to understand the causal relationship between OSA and cardiovascular disease. Finally, the effects of OAs will be updated via recent metaanalyses compared to CPAP.

• Korean Journal of Agricultural Science
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• v.35 no.2
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• pp.177-182
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• 2008

Type I Interferons (IFNs) are potent antiviral cytokines that modulate both innate immunity and adaptive immunity. Type I IFNs are immediately induced by viral infection, and stimulate production of a broad range of gene products such as double-stranded RNA-activated protein kinase (PKR), 2' 5'-oligoadenylate synthetase (OAS)/RNaseL and Mx GTPases. These proteins inhibit viral replication in host cells. Type I IFNs, in turn, lead to antiviral state at early phase of viral infection. We provide an overview of the knowledge of IFN-inducible antiviral proteins conserved in vertebrates.

• Annual Conference of KIPS
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• 2018.10a
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• pp.554-556
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• 2018

최근 인공 신경망은 다양한 분야에서 뛰어난 성능을 보여주고 있지만 인공 신경망이 학습한 지식이 어떠한 내용인지를 사람이 이해하기 어렵다는 문제점이 있다. 이와 같은 문제점을 해결하기 위한 방법 중 하나로 인공 신경망으로부터 인간이 이해할 수 있는 형태의 규칙을 추출하는 방법들이 고안이 되었다. 본 연구에서는 규칙추출 알고리즘 중 하나인 OAS 알고리즘을 이용해 규칙을 추출해보고 CDRPs(Critical Data Routing Paths)를 활용하여 추출한 규칙의 품질을 개선하는 방법을 제시하였다.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.4
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• pp.437-442
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• 2014

Recently, the needs for the development and application of the micro marine robot (MMR) which has the advantages in terms of size and cost are increasing. However, the basis is very short in the domestic. While the obstacle avoidance sonar (OAS) which was optimized in terms of size and performance and has the ability of 4-directional detection was developed for the obstacle avoidance of the micro surface robot (MSR) fortunately, the problem that the detection performance is degraded according to the shape of the obstacle because of using the fixed sonar-beam with the limited beam width and detection range exists. To solve this problem, the MSR mechanism that implements the rotating sonar-beam using the spur gear and the servo motor is proposed in this paper. To verify the performance of the proposed mechanism, the wall-tracking of the MSR is considered and the comparison and analysis in term of detection performance and actuation command is performed with conventional fixed sonar-beam. The test results show the validity of the proposed mechanism.

• Asian Journal of Atmospheric Environment
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• v.4 no.3
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• pp.150-156
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• 2010

Inter-comparison of chemical transport models (CTMs) was conducted among four modeling research groups. Model performance of the ensemble approach to $O_3$ and $PM_{2.5}$ simulation was evaluated by using observational data with a time resolution of 1 or 6 hours at four sites in the Kanto area, Japan, in summer 2007. All groups applied the Community Multiscale Air Quality model. The ensemble average of the four CTMs reproduced well the temporal variation of $O_3$ (r=0.65-0.85) and the daily maximum $O_3$ concentration within a factor of 1.3. By contrast, it underestimated $PM_{2.5}$ concentrations by a factor of 1.4-2, and did not reproduce the $PM_{2.5}$ temporal variation at two suburban sites (r=~0.2). The ensemble average improved the simulation of ${SO_4}^{2-}$, ${NO_3}^-$, and ${NH_4}^+$, whose production pathways are well known. In particular, the ensemble approach effectively simulated ${NO_3}^-$, despite the large variability among CTMs (up to a factor of 10). However, the ensemble average did not improve the simulation of organic aerosols (OAs), underestimating their concentrations by a factor of 5. The contribution of OAs to $PM_{2.5}$ (36-39%) was large, so improvement of the OA simulation model is essential to improve the $PM_{2.5}$ simulation.