• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1215-1218
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• 2008

We investigate the effect of a light emitting layer (EML) sequence and an interlayer on the performance of the phosphorescent-fluorescent mixed white organic light emitting diodes. Two types of phosphorescent-fluorescent mixed system were evaluated. The proper position of each primary color EML was crucial to obtain best performance in each system whereas the effect of an interlayer was found to be different in both systems.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1999.04a
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• pp.16.2-16
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• 1999

• Journal of Magnetics
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• v.13 no.4
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• pp.136-139
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• 2008

A simplified equation of depinning fields from notches of ferromagnetic Permalloy nanowires is presented. The derived equation is given in the form of an explicit function of nanowire width and thickness, and notch depth and angle. The equation agrees with all micromagnetic simulation results to an accuracy of ${\pm}$ 0.5 mT.

• Journal of The Korean Radiological Technologist Association
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• v.27 no.2
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• pp.66-85
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• 2001

In medical equipments as complex as a computed tomographic equipment, routine quality control procedures are essential to the detection of small pathologic change in soft tissue as well as and the maintenance of optimal image quality. This study was condu

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.310-312
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• 1993

We present the discrete event systems modeled by finite state machines in this paper using the boolean matrices and vectors. We propose a supervisor synthesis method for such boolean discrete-event systems. The proposed supervisor synthesis algorithm is practically implementable, since the size of the state vector in the product system does not increase exponentially with the number of components.

• Journal of the Korean Mathematical Society
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• v.59 no.1
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• pp.35-51
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• 2022

We give secure parameter suggestions to use sparse secret vectors in LWE based encryption schemes. This should replace existing security parameters, because homomorphic encryption (HE) schemes use quite different variables from the existing parameters. In particular, HE schemes using sparse secrets should be supported by experimental analysis, here we summarize existing attacks to be considered and security levels for each attacks. Based on the analysis and experiments, we compute optimal scaling factors for CKKS.

• Journal of Korean Academy of Nursing
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• v.41 no.3
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• pp.411-422
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• 2011

Purpose: The aim of this study was to clarify the actual condition of elders with dementia who were registered in the Seoul Dementia Management Project. Methods: Data were collected from 5,312 elderly patients with dementia. Demographic included characteristics, comorbidity, and healthy lifestyle habits; data from the Seoul Dementia Management Project. Results: First, demographic characteristics were as follows; mean age at the time of definite diagnosis was 78.0 yr. There were slightly more women (69.3%), and 4.55 yr was the average length of education with 41.4% being illiterate or uneducated patients. Second, there were several comorbidities including hypertension (61.7%), diabetes mellitus (31.8%), hypercholesterolemia (10.2%), heart disease (11.1%), obesity (4.2%), and stroke (21.4%). Third, alcoholic history was found in 11.8% of the patients, and smoking in 9.8%. Regular exercise was done by only 29.1% of the patients with dementia. Finally, significant differences between men and women were found for the following; age, education, medical security, hypertension, diabetes mellitus, stroke, alcoholic consumption, smoking, and regular exercise. Conclusion: Authors expect that the present data will be used for establishment of dementia associated projects and policies.

• Journal of Biomedical Engineering Research
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• v.35 no.6
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• pp.211-218
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• 2014

The objective of this research is to develop an automatic algorithm based on electrocardiogram (ECG) to estimate slow-wave sleep (SWS). An algorithm is based on 7 indices extracted from heart rate on ECG which simultaneously recorded with standard full night polysomnography from 31 subjects. Those 7 indices were then applied to independent component analysis to extract a feature that discriminates SWS and other sleep stages. Overall Cohen's kappa, accuracy, sensitivity and specificity of the algorithm to detect 30s epochs of SWS were 0.52, 0.87, 0.70 and 0.90, respectively. The automatic SWS detection algorithm could be useful combining with existing REM and wake estimation technique on unattended home-based sleep monitoring.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.49.5-50
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• 2021

We report the optical follow-up observations of three long γ-ray burst events, GRB 201020A, GRB 201103B and GRB 210104A by the network of telescopes in the SomangNet project. We show light curves, color evolution and SED evolution, and fit them to a single power law function to derive decay index and compare their properties with other long GRBs samples. Also, we show a good observational example that 0.4-1m class telescopes in SomangNet have potential to catch dim light from high red shift object (R>22 mag) by deep imaging. In conclusion, we found that three GRBs have optical afterglow properties of long GRB and our results are consistent with the reports of high energy analysis.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.114-121
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• 2007

The purpose of this study was to investigate 253 kinds of pesticide residues in 58 commercial dried agricultural products in Seoul. The determinations of the pesticide residues were performed using multiresidue methods and were carried out by a gas chromatography-nitrogen phosphorus detector (GC-NPD), an electron capture detector ($GC-{\mu}ECD$), a mass spectrometry detector (GC-MSD) and high performance liquid chromatography-ultraviolet detector (HPLC-UV), and a fluorescence detector (HPLC-FLD). The pesticide residue detection rate in the commercial dried agricultural products was 24.1% (14 of 58 samples). Twelve pesticide residues without maximum residue limits (MRLs) were detected. In the vegetable groups, the frequency of pesticide residues was found to be in the increasing order of dried fruiting vegetables > dried leafy vegetables > dried stalk and stem vegetables. The pesticides used on dried red pepper in the dried fruiting vegetables were varied (7 kinds) and numerous (4 of 8 samples). The pesticide types detected in the commercial dried agricultural products were in the order of pyrethroid > organochloride > organophosphorus and insecticide > fungicide > herbicide ${\cdot}$ nematicide. The primary pyrethroid pesticide detected was cypermethrin. According to the producing areas of products, large numbers of pesticide residues were found in the order of Korea, China, North Korea, USA, and Vietnam.