• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.11-15
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• 2017

We present a study of transition metal compounds using density functional theory (DFT), and density-corrected density functional theory(DC-DFT). By replacing the self-consistent density with that obtained from Hartree-Fock calculation, i.e., HF-DFT, the abnormality driven by self-interaction error is removed in several important cases. We discuss when and how HF-DFT works by examining 3d orbital dimers using approximate functionals and by comparing the results from self-consistent-DFT and HF-DFT with experimental values.

• Journal of Electrical Engineering and Technology
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• v.10 no.6
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• pp.2376-2383
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• 2015

Assistance of the operator’s walking ability while carrying a load is a challenging area in lower limb exoskeletons. We implement an exoskeleton called the Unmanned Technology Research Center Exoskeleton (UTRCEXO), which enables the operator to walk with a load more comfortably. The UTRCEXO makes use of two types of DC motor to assist the hip and knee joints. The UTRCEXO detects the operator’s walking intention including step initiation with insole-type FSRs faster without using any bio-signals and precedes the operator’s step with a reference torque. It not only reduces interaction forces between the operator and the UTRCEXO, but also allows the operator to walk with a load more comfortably. In this paper, we present the UTRCEXO implementing the walking assistance mechanism with interaction force reduction during walking.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2231-2236
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• 2005

CP (Cellular Phone) is currently one of the most attractive technologies and RT (Robot Technology) is also considered as one of the most promising next generation technology. We present a new technological concept named RCP (Robotic Cellular Phone), which combines RT and CP. RCP consists of 3 sub-modules, $RCP^{Mobility}$, $RCP^{Interaction}$, and $RCP^{Integration}$. $RCP^{Interaction}$ is the main focus of this paper. It is an interactive emotion system which provides CP with multi-emotional signal receiving functionalities. $RCP^{Interaction}$ is linked with communication functions of CP in order to interface between CP and user through a variety of emotional models. It is divided into a tactile, an olfactory and a visual mode. The tactile signal receiving module is designed by patterns and beat frequencies which are made by mechanical-vibration conversion of the musical melody, rhythm and harmony. The olfactory signal receiving module is designed by switching control of perfume-injection nozzles which are able to give the signal receiving to the CP-called user through a special kind of smell according to the CP-calling user. The visual signal receiving module is made by motion control of DC-motored wheel-based system which can inform the CP-called user of the signal receiving through a desired motion according to the CP-calling user. In this paper, a prototype system is developed for multi-emotional signal receiving modes of CP. We describe an overall structure of the system and provide experimental results of the functional modules.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.1
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• pp.33-40
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• 2006

We present a new technological concept named RCP (Robotic Cellular Phone), which combines RT and CP. That is an ubiquitous robot. RCP consists of 3 sub-modules, RCP Mobility, RCP interaction, and RCP Integration. RCP Interaction is the main focus of this paper. It is an interactive emotion system which provides CP with multi-emotional signal receiving functionalities. RCP Interaction is linked with communication functions of CP in order to interface between CP and user through a variety of emotional models. It is divided into a tactile, an olfactory and a visual mode. The tactile signal receiving module is designed by patterns and beat frequencies which are made by mechanical-vibration conversion of the musical melody, rhythm and harmony. The olfactory signal receiving module is designed by switching control of perfume-injection nozzles which are able to give the signal receiving to the CP-called user through a special kind of smell according to the CP-calling user. The visual signal receiving module is made by motion control of DC-motored wheel-based system which can inform the CP-called user of the signal receiving through a desired motion according to the CP-calling user. In this paper, a prototype system is developed far multi-emotional signal receiving modes of CP. We describe an overall structure of the system and provide experimental results of the functional modules.

• Journal of the Korea Society of Computer and Information
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• v.27 no.10
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• pp.211-222
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• 2022

The purpose of this study is to indicate the direction of the future university classes in the post-COVID era, comparing and analyzing lecture evaluation of pre and post COVID-19. To this end, 4 yeard data were used from 2018 to 2019 for pre COVID-19 and form 2020 to 2021 data for post COVID-19. The results were as follows. In the case of liberal arts, "assignments" was the word with the highest frequency and degree centrality(DC) regardless of pre and post-COVID-19 In the major, "understanding" appeared as the most important word. The result of the ego network analysis indicated that "video lecture" and "non-face-to-face classes" were difficult and "interaction" between the professor and the students was important. As a results, it is important to reduce the weight of assignments and increase interaction with students in liberal arts classes. In the case of majors, it is necessary to operate face-to-face classes rather than non-face-to-face classes, and to organize the contents of videos without difficulty.

• Restorative Dentistry and Endodontics
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• v.31 no.6
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• pp.415-426
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• 2006

In this study, the changes in the degree of conversion (DC) and the microtensile bond strength (MTBS) of self-etching adhesives to dentin was investigated according to the time after curing. The MTBS of Single Bond (SB, 3M ESPE, USA), Clearfil SE Bond (SE, Kuraray, Japan), Xeno-III (XIII, Dentsply, Germany), and Adper Prompt (AP, 3M ESPE, USA) were measured at 48h, at 1 week and after thermocycling for 5,000 cycles between 5$^{\circ}$C and 55$^{\circ}$C. The DC of the adhesives were measured immediately, at 48h and at 7 days after curing using a Fourier Transform Infra-red Spectrometer. The fractured surfaces were also evaluated with scanning electron microscope. The MTBS and DC were significantly increased with time and there was an interaction between the variables of time and material (MTBS, 2-way ANOVA, p = 0.018; DC, Repeated Measures ANOVA, p < 0.001). The low DC was suggested as a cause of the low MTBS of self-etching adhesives, XIII and AP, but the increase in the MTBS of SE and AP after 48h could not be related with the changes in the DC. The microscopic maturation of the adhesive layer might be considered as the cause of increasing bond strength.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.3
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• pp.52-68
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• 2008

Objectives and Methods : Salviae miltiorrhizae Radix (SMR) promotes blood circulation to remove blood stasis, cools the blood to relieve carbuncle, clears away heat from the heart and tranquilizes the mind. This study was designed to investigate the effects of SMR on immuno-potentiative action in terms of changes in the genetic profile of dendritic cells (DC) using by microarray analysis. Results and Conclusion: In this experiment, treatments with more than 250 ${\mu}g/ml$ upto 1000 ${\mu}g/ml$ of SMR elevated the proliferation rates of DC. Microscopic observations confirmed the tendency on proliferation rates. Expression levels of genes related with cellular methabolic process, cell communication, and macromolecule metabolic process were elevated by treatment with SMR in comparison of functional distribution in a Biological Process. In molecular functions, expression levels of genes related with receptor activation, nucleotide binding and nucleic acid binding were elevated. In cellular components, expression levels of genes related to cellular membrane-bound organelles were elevated. In addition, expression levels of genes related to Wnt signalling pathways and the glycerophospholipid metabolism were elevated through analysis using pathway analysis between up-and down-regulated genes in cells treated with SMR. Finally, genes related to JAK2, GRB2, CDC42, SMAD4, B2M, FOS and ESRI located the center of Protein interaction network of genes through treatment with SMR.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.927-933
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• 2011

Conducting polyaniline-poly($\varepsilon$-caprolactone) polymer composites were synthesized via in situ deposition techniques. By dissolving different weight percentages of poly($\varepsilon$-caprolactone) (PCL) (10%, 20%, 30%, 40%, and 50%), the oxidative polymerization of aniline was achieved using ammonium persulfate as an oxidant. FTIR, UV-vis spectra, and X-ray diffraction studies support a strong interaction between polyaniline (PANI) and PCL. Structural morphology of the PANI-PCL polymer composites was studied using scanned electron microscopy (SEM) and transmittance electron microscopy (TEM), and thermal stability was analyzed by thermogravimetric analysis (TGA) technique. The temperature-dependent DC conductivity of PANI-PCL polymer composite films was studied in the range of 305-475 K, which revealed a semiconducting behavior in the transport properties of the polymer films. Conductivity increased with the increase of PCL in below critical level, however conductivity of the polymer film was decreased with increase of PCL concentration higher than the critical value.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2967-2972
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• 2010

Poly-N-vinylcarbazole/polyaniline (PVK-PANI) composites are synthesized by varying target loading concentrations of aniline (0.025 - 0.1 M). The surface morphology of the composites is studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The temperature-dependent DC conductivity of PVK-PANI composite films was studied at the temperature range of 300 - 500 K. The data suggest that the conductivity increase with an increase in aniline concentration in the composite with an increase in temperature. Further based on the conductivity behavior we can suggest that the PVK-PANI composites show a semiconducting behavior with a positive temperature coefficient of resistivity (TCR). The enhanced conductivity and the positive TCR of the PVK-PANI composite films may be due to the strong interaction between PANI and PVK in the composite films.

• Earthquakes and Structures
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• v.24 no.1
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• pp.1-9
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• 2023

A model for calculating structure interacted mechanics is proposed. A structural interaction model and controller design based on tuned mass damping (TMD) was developed to control the induced vibration. A key point is to introduce a new analytical model to evaluate the properties of the TMD that recognizes the motion-dependent nonlinear response observed in the simulations. Aiming at the problem of increased current harmonics and low efficiency of permanent magnet synchronous motors for electric vehicles due to dead time effect, a dead time compensation method based on neural network filter and current polarity detection is proposed. Firstly, the DC components and the higher harmonic components of the motor currents are obtained by virtue of what the neural network filters and the extracted harmonic currents are adjusted to the required compensation voltages by virtue of what the neural network filters. Then, the extracted DC components are used for current polarity dead time compensation control to avert the false compensation when currents approach zero. The neural network filter method extracts the required compensation voltages from the speed component and the current polarity detection compensation method obtains the required compensation voltages by discriminating the current polarity. The combination of the two methods can more precisely compensate the dead time effect of the control system to improve the control performance. Furthermore, based on the relaxed method, the intelligent approach of stability criterion can be regulated appropriately and the artificial TMD was found to be effective in reducing cross-wind vibrations.