• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.1-6
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• 2009

Air core based transformers have been designed, simulated and fabricated by using micromachining process for the application of wireless power transmission with the range of frequency from 1 GHz to 20 GHz. Fabricated transformers are the types of solenoid transformers with primary and secondary coils. the size of fabricated transformer is $1.1{\times}1.5{\sim}2.15\;mm$ including ground shield. Transformers have been measured by dividing two groups based on the turns ratio between primary coil and secondary coil which are 1:1 transformers(the number of turns of primary coil and secondary coil: 3/3, 5/5, 7/7) and l:n transformers(the number of turns of primary coil and secondary coil: 3/3, 3/6, 3/9). As a result of the measurement, the lowest insertion loss of transformers ranged from 2 dB to 2.8 dB according to the number of turns between primary coil and secondary coil. And the lowest insertion loss from the transformers was measured at the frequency from 7 GHz to 11 GHz according to the number of turns between primary coil and secondary coil. Based on the measurement data from the microfabricated transformers, the transformer with the 3/3 turns in the primary coil and secondary coil showed best performance compared to others in terms of lowest insertion loss, lowest insertion loss frequency and bandwidth.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4B
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• pp.371-378
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• 2006

In this study, a theoretical equation was derived based on Odgaard (1986) and Chang (1988) to reveal the streamwise variation of the secondary flow in meandering channels. The new equation describes the transverse component of the secondary flow as a function of streamwise and vertical directions. To validate the proposed equation, hydraulic experiments were conducted in laboratory meandering channels having different sinuosity. Comparison of experimental results with the proposed equation and an existing equation revealed that the equation was in good agreement with the measured data. However, the existing equation overestimated the transverse velocity. Investigation of the variation of the secondary flow with respect to hydraulic parameters based on the new equation showed that the secondary flow tended to increase as the sinuosity, the roughness, and the aspect ratio became larger. Also, streamwise profile of the secondary flow was sensitive to variations of the roughness and the aspect ratio.

• Journal of the Korean Magnetic Resonance Society
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• v.8 no.2
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• pp.115-126
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• 2004

Four secondary metabolites from an unidentified tunicate were isolated by treatment with trichloroethyl chloroformate(TECF) or acetic anhydride in pyridine. Their structures were determined by an extensive NMR analysis and the configuration of diacetyl derivatives(3a, 4a) was assigned by comparing with NMR data of a similar compound. Three new naturally occurring compounds (1, 3, 4) showed potent brine shrimp lethality and antifungal effect against Candia albicans.

• Ecology and Resilient Infrastructure
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• v.4 no.1
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• pp.54-62
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• 2017

This study investigated compound open channel flow using OpenFOAM Large Eddy Simulation (LES). Large eddy simulations were carried out by solving the filtered continuity and momentum equations numerically. One equation LES and non-uniform grid were applied to capture the anisotropic turbulence and secondary flow near the wall. The results of large eddy simulations of turbulent flow in a compound open channel with deep and shallow flood plain depths are presented. These LESs are validated with experimental data, resulting in a good agreement between measured and calculated data. The role of anisotropic turbulence in generating secondary currents is illustrated.

• Journal of the Korean Magnetic Resonance Society
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• v.17 no.1
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• pp.59-66
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• 2013

BldD, a developmental transcription factor from Streptomyces coelicolor, is a homodimeric, DNA-binding protein with 167 amino acids in each subunit. Each monomer consists of two structurally distinct domains, the N-terminal domain (BldD-NTD) responsible for DNA-binding and dimerization and the C-terminal domain (BldD-CTD). In contrast to the BldD-NTD, of which crystal structure has been solved, the BldD-CTD has been characterized neither in structure nor in function. Thus, in terms of structural genomics, structural study of the BldD-CTD has been conducted in solution, and in the present work, mainchain NMR assignments of the recombinant BldD-CTD (residues 80-167 of BldD) could be achieved by a series of heteronuclear multidimensional NMR experiments on a [$^{13}C/^{15}N$]-enriched protein sample. Finally, the secondary structure prediction by CSI and TALOS+ analysis using the assigned chemical shifts data identified a ${\beta}-{\alpha}-{\alpha}-{\beta}-{\alpha}-{\alpha}-{\alpha}$ topology of the domain. The results will provide the most fundamental data for more detailed approach to the atomic structure of the BldD-CTD, which would be essential for entire understanding of the molecular function of BldD.

• Nuclear Engineering and Technology
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• v.46 no.3
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• pp.431-438
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• 2014

The effect of various pH agents on the corrosion behavior of carbon steel was investigated under a simulated secondary water chemistry condition of a pressurized water reactor (PWR) in a laboratory, and the steel's corrosion performance was compared with the field data obtained from Uljin NPP unit 2 reactor. All tests were carried out at temperatures of $50^{\circ}C-250^{\circ}C$and pH of 8.5 - 10. The pH at a given temperature was controlled by adding different agents. Laboratory data indicate that the corrosion rate of carbon steel decreased as the pH increased under the test conditions and the highest corrosion rate was measured at $150^{\circ}C$. This high corrosion rate may be related to high dissolution and instability of Fe oxide ($Fe_3O_4$) at $150^{\circ}C$. It was also found that an addition of ethanolamine (ETA) to ammonia was more effectivefor anticorrosion than ammonia alone, and that mixed treatment reduced 50% of iron or more at pHs of 9.5 or higher, especially in the steam generator (SG) and the moisture separator & re-heater (MSR).

• Korean Journal of Adult Nursing
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• v.29 no.1
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• pp.32-40
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• 2017

Purpose: The purpose of this secondary data analysis was to identify factors influencing a relapse among patients with coronary artery disease (CAD). Methods: Of 250 participants enrolled in the original study 75 were selected as there was no relapse for more than one year following the initial treatment and 54 were selected because there was a relapse. Data were analyzed using ${\chi}^2$ test, t-test or F test to determine if there were any significant differences in the study variables relative to the status of relapse. Predictors were calculated by logistic regression. Results: Autonomy supported by healthcare providers was the significant predictor for relapse in patients with CAD. Patients with low autonomy supported by healthcare providers was 3.91 times more likely to relapse than patients with high autonomy supported. Patients with diabetes were at greater risk of recurrence. Conclusion: Secondary prevention of CAD is a major task for patients with CAD. Behavioral strategies for cardiovascular risk reduction are essential and autonomy supported by healthcare providers should be included in their strategies.

• Journal of Soil and Groundwater Environment
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• v.21 no.3
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• pp.21-34
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• 2016

In the present study, we applied various machine learning techniques comparatively for prediction of subsurface structures based on multiple secondary information (i.e., well-logging data). The machine learning techniques employed in this study are Naive Bayes classification (NB), artificial neural network (ANN), support vector machine (SVM) and logistic regression classification (LR). As an alternative model, conventional hidden Markov model (HMM) and modified hidden Markov model (mHMM) are used where additional information of transition probability between primary properties is incorporated in the predictions. In the comparisons, 16 boreholes consisted with four different materials are synthesized, which show directional non-stationarity in upward and downward directions. Futhermore, two types of the secondary information that is statistically related to each material are generated. From the comparative analysis with various case studies, the accuracies of the techniques become degenerated with inclusion of additive errors and small amount of the training data. For HMM predictions, the conventional HMM shows the similar accuracies with the models that does not relies on transition probability. However, the mHMM consistently shows the highest prediction accuracy among the test cases, which can be attributed to the consideration of geological nature in the training of the model.

• Journal of Environmental Science International
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• v.25 no.12
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• pp.1673-1688
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• 2016

Gyeonghuigung palace is an important site as it was the secondary palace in Hanyang from the $17^{th}$ century to the mid-$19^{th}$ century. Its original state was lost because a number of buildings were damaged and the palace area was reduced. The entire palace can be seen only in "Seogwoldoan" a drawing of the western palace. With "Seogwoldoan" to show the complete configuration of Gyeonghuigung palace in detail as the main data and other relevant data used as supplementary sources, the aim of this work was to identify the figurative features around the plantings and the space configuration of the royal garden in Gyeonghuigung palace. The space configuration observed in the royal gardens in Gyeonghuigung palace deviated from the norms and strict systems of royal palaces. The free and uninhibited configuration of the royal garden was allowed in Gyeonghuigung palace because it was built as a secondary palace in a lower hierarchy. Furthermore, a royal garden characterized by unique and unlimited planting was created, with several spaces acting as both royal garden and rear garden as the rear gardens could not be separately configured due to the narrow space of Gyeonghuigung palace.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.3
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• pp.249-257
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• 2013

Recently, data traffic is significantly increased by high rate data service. As a result, radio spectrum is considered one of the most scarce and valuable resources for wireless communications. For the solution of this problem, cognitive radio(CR) has been proposed as an efficient means to opportunistic spectrum sharing between primary (licensed) users and cognitive radio users. In this paper, user selection scheme in CR networks is proposed for additional consideration of secondary system. The proposed user selection scheme mitigates interference to primary user by using orthogonal channel vectors while improves performance of secondary system. Simulation results show that the proposed scheme achieves 1.62bps/Hz higher average throughput of whole system than one of the existing scheme.