• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1C
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• pp.81-89
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• 2009

We propose a D-ATR UWB (Differential-Average Transmitted Reference Ultra Wide Band) system based on impulse radio. The TR-UWB systems including traditional TR (Transmitted Reference) and ATR (Average TR), exhibit a problem of reduced data rate, since reference signals are additionally transmitted. To tackle this issue, the transmitter of the proposed D-ATR system employs a differential coding like the conventional D-TR system. In addition, the receiver of the proposed system has the structure that can improve signal-to-noise ratio of the reference template used in the correlation process, by recursively averaging the received reference signals like the conventional ATR system. The simulation results in the IEEE 802.15.4a UWB multipath channel models reveal that the proposed D-ATR system achieves much better bit error rate performance as compared to the conventional D- TR system.

• Journal of Conservation Science
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• v.35 no.1
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• pp.11-18
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• 2019

The adhesives joining Buddhist scripture scrolls from medieval Korea(Goryeo Dynasty, A.D. 918~1392) are different from wheat starch adhesive. The composition of the adhesive was analyzed using Attenuated Total Reflectance-Fourier Transform Infrared(ATR-FTIR) spectroscopy. In the adhesive used to join Buddhist scripture scrolls, peaks attributed to amide I and amide II of the protein and carbohydrate were detected in the ATR-FTIR spectra, and no carbonyl peak($1745cm^{-1}$) for oil was detected in the 2nd derivative ATR-FTIR spectra. The ATR-FTIR spectra almost coincided with those of defatted soybean powder adhesive. Hence, the adhesives joining Buddhist scripture scrolls were inferred to be soybean adhesive prepared from a defatted soybean cake.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.309-310
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• 2008

In this paper, we propose a novel D-ATR (Differential-Average Transmitted Reference) scheme for UWB (Ultra Wide Band) based on impulse radio. The proposed scheme utilizing differential coding at transceiver, does not cause half loss of data rate unlike the conventional TR (Transmitted Reference) and ATR (Average TR) systems which transmit additional reference signals. In addition, the proposed scheme may provide improved BER (Bit Error Rate) performance by averaging the received reference signals like the conventional ATR. The proposed D-ATR receiver produces the averaged reference template by considering both the detected data bit and the differential coding rule.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1998.06b
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• pp.51-54
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• 1998

This paper describes the development of the 3DDAC mk.4 system, which is a brand new implementation on the research program. The 3DDAC is a fatigue-less stereoscopic display system that is provided with a compensating function of accommodation for binocular disparity 3D image representation. The mk.4 system also features a light-weight HMD style.

• Polymer(Korea)
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• v.38 no.4
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• pp.425-433
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• 2014

In this study, microstructure and gel content (C-C) of polybutadiene rubber (PBR) were investigated using various techniques including ASTM D 3616, attenuated total reflectance Fourier transform infrared spectrometry (ATR FTIR), differential scanning calorimetry (DSC) and nuclear magnetic resonance spectroscopy (NMR). The ATR FTIR spectra of the samples were investigated to determine the cis, trans, 1, 2-vinyl and the C-C gel content in PBR. The absorbance ratios of specific peaks in different grades of PBR were correlated with the C-C gel content measured by the ATR FTIR techniques. Physico-mechanical and rheological properties of rubber compounds based on BR with various amounts of gel were determined. The results showed that there is an acceptable correlation between these properties and the C-C gel content of PBR.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.117-119
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• 2004

To improve mean-life and reliability of power cable in this study, we have investigated chemical properties showing by changing the content of carbon black that is semiconductive additives for underground power transmission. Specimens were made of sheet form with the three of existing resins and the nine of specimens for measurement. Chemical properties of specimens was measured by FT-ATR (Fourier Transform Attenuated Total Reflectance). The condition of specimens was a solid sheet. We could observe functional group (C=O, carbonyl group) of specimens through FT-ATR. From these experimental result, the concentration of functional group (C=O) was high according to increasing the content of carbon black. We could know EEA was excellent more than other specimens from above experimental results.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.950-955
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• 2010

In this study, we prepared CheonJeongKiBo-Dan(7 oriental medicinal plants, 7OMP: Astragalus Membranaceus root, Panax Ginseng root, Glycyrrhiza Glabra (licorice) root, Schizandra Chinensis fruit, Polygonatum Odoratum, Rehmannia Glutinosa root, Paeonia Albiflora root) by extracting them in one reactor and studied its efficacies on skin. UV irradiation has been suggested as a major cause of photoaging in skin. In order to investigate protective effects against UV-B induced cellular damage, 7OMP was extracted with 70% ethanol and dissolved in DMSO. The protective effect was detected by MTT assay, reactive oxygen species (ROS) generation, phosphorylation of ATR and p53 in human dermal fibroblast cell system after UV-B irradiation. 7OMP reduced UV-B-induced cellular damage in HDFs cells, and inhibited ROS generation. UV-B-induced toxicity accompanying ROS production and the resultant DNA damage are responsible for activation of ATR, p53 and Bad. In this study, 7OMP hampered phosphorylations of ATR and p53 in human dermal fibroblasts. Therefore, 7OMP may be protective against UV-induced skin photoaging.

• Journal of Adhesion and Interface
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• v.20 no.3
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• pp.102-109
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• 2019

The material constitution of multi-layered thin film coated on the PET base film was analyzed using ATR FT-IR and pyro GC/MS combination. The cross section of the film was acquired by cracking the film after dipping in liquid nitrogen and was observed using optical microscope. Total thickness of the coated film was $70{\mu}m$ and three layers were observed. Since each layers were too thin to analyze directly except the surface layer, analyzable area of each layers were exposed by using a proper solvent and were investigated using ATR FT-IR and pyro GC/MS. Results shows that three layers were commonly consisted of urethane-acrylate copolymers. Also, inorganic and/or metal inclusions detected by XPS and SEM-EDAX were exhibited by nano size $SiO_2$ particles in layer(1) and aluminum flakes in layer(2).

• Korean Journal of Applied Biomechanics
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• v.33 no.2
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• pp.73-83
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• 2023

Objective: Adolescent idiopathic scoliosis patients make up 40% of all scoliosis patients, and it is likely to increase even more because of the increase in sitting times due to the pandemic. Method: The subject of this study was a 16-year-old female student. The Cobb's Angle at initial value was 42° at the thoracic and 33° at the lumbar. The subject's height was 161.6 cm, and the type of scoliosis was 3CL. The brace was built with fabric materials with the size information from the X-ray information and actual measurements. The brace was made for the adolescents to wear for a longer time by making them put pressure on the same pressure points of the existing braces. The subjects were required to wear the device for 16 hours every day for three months. Additional features to check the pressure and time were synchronized through an app for easier communication and management with the responsible investigator. Results: After wearing the 3D Fabric brace, Cobb's angle changed from 42° to 33° at the thoracic and 33° to 23° at the lumbar. The ATR changed from 9° to 8° at the thoracic and 11° to 6° at the lumbar. As a result, the changes in the ATR angle do relate to the decrease of Cobb's angle, which made the angle of scoliosis that is bent in a three-dimensional way improve, making the height of the subject increase from 161.6 cm to 163.5 cm. Conclusion: Through this study, developing a brace that is made in the form of the 3CL to align the strap direction and putting pressure on the proper pressure points makes Cobb's angle and the ATR smaller. This means that there is a positive effect on the changes in height. A brace made of light fabric material is a good brace to help treat adolescent idiopathic scoliosis. There was an opinion that it is more comfortable to wear than existing braces, but it seems necessary to conduct a quantitative study about the before and after of wearing the brace and a survey for Korean specific cases.

• Macromolecular Research
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• v.15 no.6
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• pp.560-564
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• 2007

The photostabilization and cure kinetics of UV-curable, optical resins containing various formulations of photostabilizers were investigated to determine the system with the highest cure conversion and durability. Photo-DSC analysis revealed that increasing the concentration of a UV absorber (UVA) decreased both the crosslink density and the cure rate due to competition for the incident photons between the photoinitiator and the UVA, whereas including a hindered amine light stabilizer (HALS) hardly affected either the cure conversion or the cure rate due to its very low absorption of 365 nm. This result was confirmed by FTIR-ATR spectroscopy and UV-visible spectroscopy analyses. QUV ageing experiments showed that the cure conversion and durability were the highest for the UVA/HALS formulation at a ratio of 1 : 2, which is due to their synergistic action.