• Journal of Advanced Navigation Technology
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• v.21 no.3
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• pp.251-257
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• 2017

Recently, hybrid positioning system combining GPS, vision sensor, and inertial sensor has drawn many attentions to estimate accurate vehicle positions. Since accurate multi-sensor fusion requires efficient time synchronization, this paper proposes an efficient method to obtain time synchronized measurements of vision sensor, inertial sensor, and OBD device based on GPS time information. In the proposed method, the time and position information is obtained by the GPS receiver, the attitude information is obtained by the inertial sensor, and the speed information is obtained by the OBD device. The obtained time, position, speed, and attitude information is converted to the color information. The color information is inserted to several corner pixels of the corresponding image frame. An experiment was performed with real measurements to evaluate the feasibility of the proposed method.

• Journal of Life Science
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• v.14 no.2
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• pp.291-295
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• 2004

Rooibos (Aspalathus linearis) (RB) is a leguminous shrub native to the mountainous areas of the northwestern Cape Province in South Africa. RB tea infusions are the fermentation products of its leaves and fine sterns, and known to have a high antioxidative activity due to the presence of flavonoids and phenolic acids. We investigated the effects of RB tea on the alleviation of oxidative stress on cultured rat cortical neurons in a hypoxic model. Measurement of lactate dehydrogenase (LDH) released into culture media revealed that RB increased cell viabilities in both normoxia (6-18%) and hypoxia (2-24%) dose-dependently (10-100 $\mu\textrm{g}$/ml) on 16 days in vitro (3 days after treatment). Visualization of cell morphology by expression of GFP-Hsc70 fusion protein showed that RB (50 $\mu\textrm{g}$/ml) reduced the average vacuolated soma from 55.4$\pm$4.59% (no RB addition) to 40.9$\pm$6.3% (RB addition) on 5 days after hypoxia. Our results proves efficacy of RB in the neuroprotection of hypoxic neurons and extend application for RB into the prevention and/or treatment of neuronal damages.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.2
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• pp.139-147
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• 2009

The gravity data collected and reserved in Korea is seriously biased in its distribution. That is, only the west-southern part of the peninsula including Chungcheong and Jeonla area has dense distribution while only a part is covered in Gyoungsang area. Especially, the low density of the gravity data in mountainous area basically limits the accuracy of the gravimetric geoid in Korea. As one of the solution to overcome the problem, an airborne gravity survey were conducted from Dec. 2008 $\sim$ Jan. 2009. In this study, free-air gravity anomaly derived from the airborne gravity data which has consistent quality are presented. The data processing for the airborne gravity is composed of several corrections of errors such as errors from gravity measurement, errors from flight dynamics, errors from GPS, and errors from time synchronization. We presented detailed explanations on the data processing with the final cross-over results. The free-air anomaly from airborne gravity finally shows the cross-over accuracy of 2.21mGal which reflects the precision of each track is 1.56mGal. It is expected that the result from this study will play a role as input data in precision geoid determination with ground and ship-borne gravity data after appropriate fusion process.

• Journal of the Korean Society of Radiology
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• v.15 no.2
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• pp.257-263
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• 2021

This study derives the relative cross-section for the natW(p,xn)176Re nuclear reaction by measuring the gamma rays generated from the nuclear reaction with natural tungsten using a 100 MeV linear accelerator of the Korea Multi-purpose Accelerator Complex in the Korea Atomic Energy Research Institute. In general, research on isotopes with a short half-life always shows a tendency that the intensity of radioactivity decreases rapidly within a short period of time, making it very difficult to measure itself. In particular, 176Re is one of the relatively short radionuclides with a half-life of 5.3 minutes. In this study, 109.08 keV gamma rays generated from the 176Re isotope having such a short half-life were measured using a high-purity Ge detector(HPGe detector). The obtained relative measurements were the results in the 8 to 14 MeV proton energy domain published by Richard G. in 1967, and the TENDL-2019 value, which was the result of A. J. Koning in 2019, which evaluated the nuclear reaction cross-section by calculation based on this comparative analysis was performed. The results of this study are expected to be usefully applied to the design of nuclear fusion reactor which is known as future energy sources, elements ratio for the nuclear synthesis of astrophysics.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.71-77
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• 2022

To increase biomass utilization, rice husk-based activated carbon (RHAC) followed by nitrogen plasma surface treatment was prepared and the electric double-layer capacitor performance was investigated. Through nitrogen plasma surface treatment, up to 2.17% of nitrogen was introduced to the surface of RHAC, and in particular the sample reacted for 5 min with nitrogen plasma showed dominant formation of pyrrolic/pyridine N functional groups. In addition, mesopores were formed on the RHAC material by the removal of silica, and the surface roughness of the carbon material increased by nitrogen plasma surface treatment, resulting in the formation of many micropores. As a result of cyclic voltammetry measurement, at a scan rate of 5 mV/s, the specific capacitance of the RHAC treated with nitrogen plasma increased up to 200 F/g, showing an 80.2% improvement compared to that of using untreated RHAC (111 F/g). This is attributed to the synergetic effect of the introduction of pyrrolic/pyridine-based nitrogen functional groups and the increase of the micropore volume on the surface of the carbon material. This study has a positive effect on the environment in terms of recycling waste resources and using plasma surface treatment.

• Restorative Dentistry and Endodontics
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• v.48 no.3
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• pp.22.1-22.8
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• 2023

Objectives: This study was conducted to evaluate and compare the tip and taper compatibility of accessory gutta-percha points (AGPs) with various rotary and reciprocating instruments. Materials and Methods: Using a profile analyzer, tip and taper measurements were taken of 10 AGPs of each of the 14 models available from Odous de Deus and the 4 models available from Dentsply-Maillefer. Diameter measurements were taken at 1-mm intervals, from 3 mm from the tip (D3) to 16 mm. Results: Based on the mean values obtained, 3-dimensional (3D) models of the AGPs were drawn in Autodesk Fusion 360 and superimposed on 3D models of each instrument selected (Mtwo, Reciproc, RaCe, K3, and ProDesign Logic) to determine the compatibility between the instrument and the AGP. Data corresponding to the tips and tapers of the various AGPs, as well as the tip and taper differences between the AGPs and the instruments, were analyzed using descriptive statistics. The tapers of the AGPs were subject to the American National Standards Institute/American Dental Association No. 57 standard. The Odous de Deus extra-long medium and extra-long extra-medium AGPs were shown to be compatible with Mtwo, K3, and ProDesign Logic instruments with taper 0.06 and tip sizes 25 and 30, while the Dentsply fine and fine medium cones were compatible with Mtwo, RaCe, and K3 instruments with conicity of 0.04 and tip sizes 35 and 40. Conclusions: Both the Odous de Deus and Dentsply commercial brands included 2 AGP models with tip (D3) and taper compatibility with Mtwo, RaCe, K3, and/or Prodesign Logic instruments.

• CELLMED
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• v.14 no.10
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• pp.12.1-12.13
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• 2024

This study investigated the psychological effects of the creative music fairy tale 'I am a music creator' education program, which was implemented as the convergence educational program of the Seocho Innovation Education District in 2021 for a total of 8 weeks for elementary school students, on Musical Interest, Self-Efficacy, and Self-Esteem. Before verifying the effects after conducting the education program for a total of 8 weeks, a homogeneity verification of the group composition was conducted through a pre-measurement, and it was confirmed that the composition by gender and grade was homogeneous. The results of this study are as follows. First, the results of the pre-test/post-test by research subject showed that the post-test scores in Musical-Interest and Self-Efficacy were slightly higher than the pre-test scores, but there was no significant difference. When Self-Esteem was considered, There was a significant difference, and the post-test scores showed a higher average than the pre-test scores. Second, the results of the pre-test/post-test by gender of the research subject showed that the post-test scores in Musical-Interest, Self-Efficacy, and Self-Esteem for male students were slightly higher than the pre-test scores, but there was no significant difference. The post-test scores in Musical-Interest and Self-Efficacy for female students were slightly higher than the pre-test scores, but there was no real significant difference. Self-Esteem showed a significant difference, and the post-test scores showed a higher average than the pre-test scores. Third, the results of the pre-test/post-test by grade of the research subject showed that the post-test scores in Musical-Interest, Self-Efficacy, and Self-Esteem for second graders were slightly higher than the pretest scores, but there was no real significant difference. In the 3rd grade, there was a significant difference in the sub-factors of Musical-Interest, interest in music classes, and Self-Esteem, and the post-score showed a higher average than the pre-score. In the 4th grade, the post-scores were slightly higher than the pre-scores in Musical-Interest, Self-Efficacy, and Self-Esteem, but there was no significant difference. Through these results, it was confirmed that the integrated music activity approach has a positive influence on elementary school students' Musical-Interest, Self-Efficacy, and Self-Esteem, which are formed in the process of growth and development.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.1
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• pp.25-32
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• 2019

Purpose: The size, shape, and volume of prosthetic appliance depend on the metal artifacts resulting from dental implant during head and neck treatment with radiation. This reduced the accuracy of contouring targets and surrounding normal tissues in radiation treatment plan. Therefore, the purpose of this study is to obtain the images of metal representing the size of tooth through MVCT, SMART-MAR CT and KVCT, evaluate the volumes, apply them into the proton therapy plan, and analyze the difference of dose distribution. Materials and Methods : Metal A ($0.5{\times}0.5{\times}0.5cm$), Metal B ($1{\times}1{\times}1cm$), and Metal C ($1{\times}2{\times}1cm$) similar in size to inlay, crown, and bridge taking the treatments used at the dentist's into account were made with Cerrobend ($9.64g/cm^3$). Metal was placed into the In House Head & Neck Phantom and by using CT Simulator (Discovery CT 590RT, GE, USA) the images of KVCT and SMART-MAR were obtained with slice thickness 1.25 mm. The images of MVCT were obtained in the same way with $RADIXACT^{(R)}$ Series (Accuracy $Precision^{(R)}$, USA). The images of metal obtained through MVCT, SMART-MAR CT, and KVCT were compared in both size of axis X, Y, and Z and volume based on the Autocontour Thresholds Raw Values from the computerized treatment planning equipment Pinnacle (Ver 9.10, Philips, Palo Alto, USA). The proton treatment plan (Ray station 5.1, RaySearch, USA) was set by fusing the contour of metal B ($1{\times}1{\times}1cm$) obtained from the above experiment by each CT into KVCT in order to compare the difference of dose distribution. Result: Referencing the actual sizes, it was appeared: Metal A (MVCT: 1.0 times, SMART-MAR CT: 1.84 times, and KVCT: 1.92 times), Metal B (MVCT: 1.02 times, SMART-MAR CT: 1.47 times, and KVCT: 1.82 times), and Metal C (MVCT: 1.0 times, SMART-MAR CT: 1.46 times, and KVCT: 1.66 times). MVCT was measured most similarly to the actual metal volume. As a result of measurement by applying the volume of metal B into proton treatment plan, the dose of $D_{99%}$ volume was measured as: MVCT: 3094 CcGE, SMART-MAR CT: 2902 CcGE, and KVCT: 2880 CcGE, against the reference 3082 CcGE Conclusion: Overall volume and axes X and Z were most identical to the actual sizes in MVCT and axis Y, which is in the superior-Inferior direction, was regular in length without differences in CT. The best dose distribution was shown in MVCT having similar size, shape, and volume of metal when treating head and neck protons. Thus it is thought that it would be very useful if the contour of prosthetic appliance using MVCT is applied into KVCT for proton treatment plan.