• Journal of Pharmaceutical Investigation
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• v.26 no.3
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• pp.169-174
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• 1996

Inclusion complexes of diclofenac sodium with ${\beta}-cyclodextrin$ were prepared in aqueous solution, alkaline solution and solid phase. The interaction of diclofenac sodium with ${\beta}-cyclodextrin$ in pH 9.0 alkaline solution was evaluated by the solubility method and the instrumental analysis such as thermal analysis, infrared spectroscopy, X-ray diffractometry. The solubility of diclofenac sodium was increased linearly with the increase in the concentration of ${\beta}-cyclodextrin$up to 0.15 mol and showed that the aqueous solubility rate of diclofenac sodium was significantly increased by complex with ${\beta}-cyclodextrin$. The optimum composition of this complex was one molecule of ${\beta}-cyclodextrin$ included 1.59 molecular weight of diclofenac sodium as a guest molecule. The pharmacokinetic parameters of the diclofenac sodium and the complex with ${\beta}-cyclodextrin$ were studied in rats by oral route. $T_{max}$ between drug alone and inclusion complex showed significant difference to be 120 minute and 20 minute respectively. Both of $C_{max}$ and AUC of inclusion complex was about 40% higher than drug alone. It is estimated from the data in this study that complexation of diclofenac sodium with ${\beta}-cyclodextrin$ increased the absorption rate and improved the bioavalability of the diclofenac sodium by the formation of a water-soluble complexes.

• The Journal of Advanced Prosthodontics
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• v.5 no.2
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• pp.110-117
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• 2013

PURPOSE. Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism. MATERIALS AND METHODS. Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature ($T_g$) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS. The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION. Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.

• Restorative Dentistry and Endodontics
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• v.43 no.2
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• pp.26.1-26.12
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• 2018

Objective: The purpose of this study was to investigate the degree of conversion (DC) and mechanical properties of a microhybrid Filtek Z250 (3M ESPE) resin composite after aging. Method: The specimens were fabricated using circular molds to investigate Vickers microhardness (Vickers hardness number [VHN]) and DC, and were prepared according to ISO 4049 for flexural strength testing. The initial DC (%) of discs was recorded using attenuated total reflectance-Fourier transforming infrared spectroscopy. The initial VHN of the specimens was measured using a microhardness tester under a load of 300 g for 15 seconds and the flexural strength test was carried out with a universal testing machine (crosshead speed, 0.5 mm/min). The specimens were then subjected to thermocycling in $5^{\circ}C$ and $55^{\circ}C$ water baths. Properties were assessed after 1,000-10,000 cycles of thermocycling. The surfaces were evaluated using scanning electron microscopy (SEM). Data were analyzed using 1-way analysis of variance followed by the Tukey honest significant difference post hoc test. Results: Statistical analysis showed that DC tended to increase up to 4,000 cycles, with no significant changes. VHN and flexural strength values significantly decreased upon thermal cycling when compared to baseline (p < 0.05). However, there was no significant difference between initial and post-thermocycling VHN results at 1,000 cycles. SEM images after aging showed deteriorative changes in the resin composite surfaces. Conclusions: The Z250 microhybrid resin composite showed reduced surface microhardness and flexural strength and increased DC after thermocycling.

• Journal of The Korean Astronomical Society
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• v.52 no.3
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• pp.71-82
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• 2019

We derive the geometric albedo of a near-Earth asteroid, (4179) Toutatis, to investigate its surface physical conditions. The asteroid has been studied rigorously not only via ground-based photometric, spectrometric, polarimetric, and radar observations but also via in situ observation by the Chinese Chang'e-2 space probe; however, its geometric albedo is not well understood. We conducted V-band photometric observations when the asteroid was at opposition in April 2018 using the three telescopes in the southern hemisphere that compose the Korea Microlensing Telescope Network (KMTNet). The observed time-variable cross section was corrected using the radar shape model. We find that Toutatis has a geometric albedo $p_V=0.185^{+0.045}_{-0.039}$, which is typical of S-type asteroids. We compare the geometric albedo with archival polarimetric data and further find that the polarimetric slope-albedo law provides a reliable estimate for the albedo of this S-type asteroid. The thermal infrared observation also produced similar results if the size of the asteroid is updated to match the results from Chang'e-2. We conjecture that the surface of Toutatis is covered with grains smaller than that of the near-Sun asteroids including (1566) Icarus and (3200) Phaethon.

• Journal of The Geomorphological Association of Korea
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• v.28 no.1
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• pp.83-99
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• 2021

Burn severity analysis using satellite imagery has high capabilities for research and management in inaccessible areas. We extracted the forest fire area of the DMZ (Demilitarized Zone) in the western Imjin Estuary which is restricted to access due to the confrontation between South and North Korea. Then we analyzed the forest fire severity and recoverability using atmospheric corrected Surface Reflectance Level-2 data collected from Landsat-8 OLI (Operational Land Imagery) / TIRS (Thermal Infrared Sensor). Normalized Burn Ratio (NBR), differenced NBR (dNBR), and Relative dNBR (RdNBR) were analyzed based on changes in the spectral pattern of satellite images to estimate burn severity area and intensity. Also, we evaluated the recoverability after a forest fire using a land cover map which is constructed from the NBR, dNBR, and RdNBR analyzed results. The results of dNBR and RdNBR analysis for the six years (during May 30, 2014 - May 30, 2020) showed that the intensity of monthly burn severity was affected by seasonal changes after the outbreak and the intensity of annual burn severity gradually decreased after the fire events. The regrowth of vegetation was detected in most of the affected areas for three years (until May 2020) after the forest fire reoccurred in May 2017. The monthly recoverability (from April 2014 to December 2015) of forests and grass fields was increased and decreased per month depending on the vegetation growth rate of each season. In the case of annual recoverability, the growth of forest and grass field was reset caused by the recurrence of a forest fire in 2017, then gradually recovered with grass fields from 2017 to 2020. We confirmed that remote sensing was effectively applied to research of the burn severity and recoverability in the DMZ. This study would also provide implications for the management and construction statistics database of the forest fire in the DMZ.

• Smart Structures and Systems
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• v.33 no.1
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• pp.55-64
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• 2024

This paper proposes a fusion imaging-based coating-defect classification method for steel structures that uses zero-shot learning. In the proposed method, a halogen lamp generates heat energy on the coating surface of a steel structure, and the resulting heat responses are measured by an infrared (IR) camera, while photos of the coating surface are captured by a charge-coupled device (CCD) camera. The measured heat responses and visual images are then analyzed using zero-shot learning to classify the coating defects, and the estimated coating defects are visualized throughout the inspection surface of the steel structure. In contrast to older approaches to coating-defect classification that relied on visual inspection and were limited to surface defects, and older artificial neural network (ANN)-based methods that required large amounts of data for training and validation, the proposed method accurately classifies both internal and external defects and can classify coating defects for unobserved classes that are not included in the training. Additionally, the proposed model easily learns about additional classifying conditions, making it simple to add classes for problems of interest and field application. Based on the results of validation via field testing, the defect-type classification performance is improved 22.7% of accuracy by fusing visual and thermal imaging compared to using only a visual dataset. Furthermore, the classification accuracy of the proposed method on a test dataset with only trained classes is validated to be 100%. With word-embedding vectors for the labels of untrained classes, the classification accuracy of the proposed method is 86.4%.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.3
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• pp.8-16
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• 1986

The fishing conditions of flying squid, ommastrePhes barsram(Lesueur), in the North Pacific Ocean was studied based on the horizontal water temperature data, satellite data from NOAA and statistical data of flying squid fisheries which were collected from 1980 to 1984. The obtained results were as follows; 1. Since 1979, the Korean drift giIlnet fishery for flying squid was launched in North Pacific. Number of operating vessel and catch of flying squid increased gradually every year. The number of vessels were 111 and their annual catches were 42, 977 M/T in 1984. Therefore, Korean drift giIlnet fishery for this species has played an important role in the products of Korean high-sea fisheries. 2. In the beginning of the fisheries, fishing grounds was formed in the west of long. 1800E. In 1982, in consequence of the center which extended eastward, the fishing ground was formed long. 166$^{\circ}$W in the central North Pacific Ocean. Since 1983, the fishing grounds were formed as far as long. 161$^{\circ}$W. The range of general fishing season in the central North Pacific was from June to August. After september, fishing ground was shifted to the west, in the Northwestern Pacific. 3. The Predominant fishing season for the flying squid was August through January of the coming year. Optimum water temperature for flying sguid at surface layer in the Pacific Ocean ranged from 11 $^{\circ}$e to 17$^{\circ}$e in winter, 13$^{\circ}$e to 17$^{\circ}$e in spring, 12. 8$^{\circ}$C to 19.7$^{\circ}$e in summer and 1O.6$^{\circ}$e -18.7$^{\circ}$e in fall. 4. In summer, the Oceanographic condition in the North Pacific Ocean showed that the water temperature at surface layer was lower in 1980, 1983 and higher in 1981, 1982 and 1984 as compared with mean annual water temperature. 5. The characteristics df oceanographic conditions in the fluation, disformation, mixing and other factors of the Kuroshio and Oyashio currents, which have considerably influenced upon the water masses of the areas. 6. The data and information on surface thermal Structure interpreted from Infrared Satellite Imaginary from NOAA-7 and NOAA-8 are very available in estimating water temperature on the areas and investigating the major fishing grounds. 7. According to the fisheries statics of Japanese drift gilInet, the annual catches of flying squid considerably decreased from 225, 942 M/T in 1983 to 133, 217 M/T in 1984. 8. The fishing grounds in the central North Pacific in several fishing seasons were formed as follows: In June, the initial fishing season, the fishing grounds were formed in the vicinity of lat. 35 - 40oN, the central North Pacific east of 179$^{\circ}$E. In July, the fishing ground were formed in the wide arEa of the central North Pacific north of 400N and long. 174$^{\circ}$E-145$^{\circ}$W In Auguest, concentrative fishing operation carried out in :he central North Pacific north of 43$^{\circ}$N and East of 165$^{\circ}$W. On the other hand, in September, main fishing grounds were disappeared and moved to the west.

• Journal of Navigation and Port Research
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• v.40 no.3
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• pp.159-164
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• 2016

The goal of this study is to implement a communication system that can monitor the status of the nacelle using the power cable itself, without the dedicated communication lines such as an UTP cable and optical fiber for the offshore wind turbine. An inductive coupling powerline communication system for a MW class offshore wind turbine was proposed and its communication performance was demonstrated. The inductive couplers was designed for operation at up to 500 A using a ferrite composite materials. Field test was carried out on the wind farms of Jeju island. Using the iperf communication test program, we have obtained more than 15 Mbps data transmission rate through the 100 m power cable that was installed between the nacelle and the bottom of the power converter. In the data transmission stability test for a week, there was no failure ever. The minimum transmission rate was 15 Mbps and the average data rate was about 20 Mbps. Next, we have installed an infrared camera inside the nacelle in order to measure the temperature distribution and variation of the nacelle. The real-time thermal image taken by the camera was successfully sent to the monitoring system without error.

• Korean Journal of Remote Sensing
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• v.16 no.3
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• pp.211-220
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• 2000

Even though recurring eddies at the terminal end of the East Korean Warm Current have been identified in the thermal infrared imagery from the NOAA/AVHRR sensor and ocean color data from Orbview-2/SeaWiFS sensor, it is difficult to make observation in the field regarding recurring eddies located around the Wonsan coastal area in North Korea. But we could get in situ data related to an eddy from an ARGOS satellite tracking drifter trapped in the eddy on January 4th, 1999. An ARGOS drifter, a NOAA satellite tracked buoy was trapped by the eddy during January 4th.March 18, 1999. The ARGOS drifter rotated 10 times per 72 days on the edge of the eddy located at $39^{\circ}N$, $129^{\circ}E$. The diameter of the eddy was about 100 km. The horizontal rotation velocity of the recurring cold-core anti-cyclonic eddy was 1.53 km/h(42 cm/sec). The sea surface temperatures of the eddy varied from $14.7^{\circ}C$ on January 5, 1999 to $9.6^{\circ}C$ on March 18,1999. To study the mechanism of the recurring eddy. we tried to find out the relationship between the vector of the drifter moving in the eddy and the wind vector in Sokcho and Ulleung Island located near the eddy in southern Korea, and the difference in sea level between Ulleung Island and Mukho. We hope the results of this study would be useful for calibration and validation data of simulation and numerical modeling studies of the recurring eddy.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.4
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• pp.179-184
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• 2021

Along with the development of the fourth industry, the public sector has increasingly paid more attention to search using drones and real-time monitoring, for various goals. The drones are used and researched to complete a variety of searching and monitoring missions, including search for missing persons, security, coastal patrol and monitoring, speed enforcement, highway and urban traffic monitoring, fire and wildfire monitoring, monitoring of illegal fishing in reservoirs and protest rally monitoring. Police stations, fire departments and military authorities, however, concentrate on the hardware part, so there are little research on efficient communication systems for the real-time monitoring of data collected from high-performance resolution and infrared thermal imagining cameras, and analysis programs suitable for special missions. In order to increase the efficiency of drones with the searching mission, this paper, therefore, attempts to propose an image analysis technique to increase the precision of search by producing image data suitable for searching missions, based on images obtained from drones and provide the foundation for improving relevant policies and establishing proper platforms, based on actual field cases and experiments.