• The Journal of Korean Academy of Prosthodontics
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• v.61 no.2
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• pp.160-178
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• 2023

Diagnosis and analysis of occlusal relationships are important factors in prosthetic treatment. A thorough occlusion analysis and evaluation should be performed before treatment to restore a stable interocclusal relationship. Analysis and evaluation are essential during the treatment process and at regular follow-ups. Recently, with the development of dental equipment and digital processing methods, new quantitative analysis methods that can record the patient's occlusal relationship have been introduced. Among them, the T-Scan Novus (Tekscan Inc., S. Boston, MA, USA) displays the strength of the initial contact point and the occlusal contact point of the teeth using a pressure sensor. With this, occlusal contact time of the teeth, anteroposterior and left-right balance of occlusal force can be compared. The Dental prescale II (GC Co., Tokyo, Japan) scans the occlusal contact point using a pressure-sensing film and analyzes the density of the contact point. It can measure the distribution and strength of the occlusal force of the teeth in the most natural occlusion state. Based on this, appropriate prosthetic treatment (four-unit fixed partial denture, removable partial denture, complete denture, and complete oral restoration cases) was performed according to the area and extent of the patient's tooth loss. The patient's occlusion at the first visit, treatment stage, right after treatment, and regular follow-up were compared and evaluated using a quantitative method for appropriate occlusion analysis using T-Scan Novus and Dental prescale II. This report enhances the understanding of occlusion analysis during prosthetic restoration. The results satisfied both the clinician and patients in terms of function and aesthetics.

• Journal of Adhesion and Interface
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• v.23 no.4
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• pp.122-129
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• 2022

In this study, the hydrophilicity of the metal fiber is improved by introducing an oxygen-containing functional group to the fiber surface after treatment of the metal fiber using the oxygen plasma treatment time as an experimental variable. For the surface modification of metal fibers, changes in surface properties before and after plasma treatment were observed using SEM and x-ray photoelectron spectroscopy (XPS). In order to observe the effect of the plasma treatment time on the surface of the metal fiber, the change in contact angle of the metal fiber with respect to a polar solvent and a non-polar solvent was measured. After calculating the change in surface free energy using the measured contact angle, the contact angle and the surface free energy for metal fibers before and after oxygen plasma treatment were compared, and the correlation with the adhesion work was also considered. The microdroplet specimens were prepared to investigate the effect of surface changes of these metal fibers on the improvement of shear strength at the interface when combined with other materials and the interfacial shear strength was measured, and the correlation with the adhesion work was also identified. Therefore, the oxygen plasma treatment of the metal fiber results in an increase in the physical surface area on the fiber surface and a change in contact angle and surface energy according to the introduction of the oxygen-containing functional group on the surface. This surface hydrophilization resulted in improving the interfacial shear strength with the polymer resin.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.161-169
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• 2023

Thrips are usually not exposed to insecticide spray due to hiding at holes, gaps, or crevices of host plants with their relatively small body sizes. This study devised a strategy to use a contact pheromone to suppress the seclusive behavior of the thrips, A contact pheromone identified as 7-methyltricosane (7TM) in the western flower thrips, Frankliniella occidentalis, was added to the diet to test the preference of the thrips. Although 7TM did not change the larval behavior, it significantly induced the avoiding behavior in male adults. In contrast, the contact pheromone was preferred by the female adults. Similar behavioral changes were also observed in another flower thrips, Frankliniella intonsa. Based on the behavioral changes induced by the contact pheromone, a mixture of 7TM and insecticide was applied to thrips infesting hot peppers in field conditions. Compared to spinetoram treatment, its mixture treatment with 7TM enhanced the control efficacy against thrips. Interestingly, 7TM treatment alone also gave slight reduction in F. intonsa density, suggesting a behavioral disruption of thrips by the contact pheromone. This study suggests a novel technology to control insect pests using contact pheromone by suppressing the seclusive behavior to avoid exposure to insecticide spray.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.6
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• pp.19-27
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• 2018

The stone pagoda structure is treated as a discontinuous masonry structure, and the contact surface characteristics between stones is a very important factor in the discontinuum behavior analysis. So, it is necessary to find out material and structural characteristics of stone contact surface to perform the structural analysis for safety evaluation. Accordingly, it is important to analyze the material properties of stone surface and secure the structural characteristics through various contact surface states. Therefore, in this study, various test specimens applying the filler between the surface roughness and the stone in the contact surface treatment technique of the stone pagoda were manufactured, and compression test and shear test were carried out. Also, we analyzed the material and structural characteristics of the stone contact surface through the comparison of experimental results.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1098-1102
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• 2008

To increase the ink transfer rate in the micro-gravure-offset printing, the liquid transfer process between two separating plates is investigated. During the liquid transfer process, in which one plate is fixed and the other one moves vertically, a sessile droplet is separated into two droplets. The volume ratio of the two droplets depends on the contact angles of the two plates. In a numerical study of the ink transfer processes, liquid transfer between two parallel separating plates and between a trapezoidal cavity and an upward moving plate are simulated, as models of the printing of ink from the offset pad onto the substrate and the picking up of ink from the gravure plate by the offset pad, respectively. Also, in experimental study, to obtain various surface contact angles, chemical treatment, plasma treatment, and electrowetting- on-dielectric (EWOD) surface are considered. The transfer rate between two plates is calculated by analyzing the droplet images. From the results, the optimal surface contact angles of the units of the micro-gravure-offset printing can be characterized.

• Herbal Formula Science
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• v.13 no.2
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• pp.59-69
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• 2005

Samyoyongantang (SMY), a herbal medicine, has been used as cure for gangrene. To evaluate anti-inflammatory effect of samyoyongantang, we treated samyoyongantang extract in animal model system induced contact hypersensitivity. Contact hypersensitivity, a local inflammatory response of the skin, was induced by 1% DNCB on the right ear of BALB/c mouse. Samyoyongantang was prepared as water extract and administrated everyday for 2 weeks per oral. A right ear of mouse was potently swelled by 1% of DNCB treatm ent, but a mouse ear thickness was significantly reduced by samyoyongantang after 2 we eks treatment. Samyoyongantang reduced IgG in serum obtained from blood of 1 % DNCB-treated mouse. IgE in serum was not changed by samyoyongantang treatment. From these results, anti-inflammatory effect of samyoyongantang, especially reduction of ear swell ing, might be partly due to reduction of IgG in serum.

• Journal of the Korean Society for Heat Treatment
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• v.9 no.3
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• pp.169-176
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• 1996

Effect of retained austenite on rolling contact fatigue of nitrocarburized high-carbon chromium bearing steel has been investigated to develop surface-hardened bearing steel with imprved resistance to rolling contact fatigue. Fatigue tests were conducted in elesto-hydrodynamic lubricating conditions at a shaft speed of 5,000rpm, under max, hertzian stress of $492kg/mm^2$. Volume fraction of retained austenite in austenitic nitrocarburized STB2 steel was controlled by tempering at various temperature, $200{\sim}250^{\circ}C$. It was observed using TEM that decomposition of retained austenite during tempering at $250^{\circ}C$ was the highest in quantity, resulted in formation of lower bainite. Rolling contact fatigue life of the specimens with lower bainite, formed by decomposition of retained austenite, was improved in comparison with there of specimens with more amount of retained austenite.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.12
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• pp.1981-1987
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• 2001

This paper documents the effect of surface treatment of aluminum on the bonding strength of aluminum/CFRP composites. The surface of aluminum panel was treated by DC plasma. The optimal treatment condition of the aluminum was determined by measuring the contact angle and T-peel strength as functions of mixture ratio of acetylene gas to nitrogen gas. The mixture ratios used were 1:9, 3:7, 5:5, 7:3, and 9:1 Lap shear tests and T-peel tests were performed using surface-treated alumiunm/CFRP composites and regular alumiunm/CFRP composites. The results showed that the contact angle was minimized and the T-peel strength was maximized iota the mixture ratio of 5:5. The results also showed that the shear strength of surface-treated alumiunm/CFRP composites was 34% greater than that of regular alumiunm/CFRP composites. The T-peel strength of surface-treated alumiunm/CFRP composites was also 5 times greater than that of regular alumiunm/CFRP composites.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1174-1177
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• 2006

A bottom contact organic thin film transistor (OTFT) is fabricated with an organic double-layered gate insulator (GI) and pentacene. The PMMA and MNB layers are treated on gate insulator and source/drain (S/D, Au) before depositing pentacene to investigate device properties and pentacene growth. The sequence of surface treatment affects a device performance seriously. The ultra-thin PMMA (below 50A) was deposited on organic gate insulator and S/D metal by spin coating method, which showed no deterioration of on-state current (Ion) although bottom contact structure was exploited. We proposed that the reason of no contact resistance (Rc) increase may be due to a wettability difference in between PMMA / Au and PMMA / organic GI. As a result, the device treated by $PMMA\;{\rightarrow}\;MNB$ showed much better Ion behavior than those fabricated by $MNB\;{\rightarrow}\;PMMA$. We will report the important physical and electrical performance difference associated with surface treatment sequence.

• Journal of Environmental Science International
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• v.11 no.12
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• pp.1267-1274
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• 2002

This study was carried out to evaluate the pollutant removal efficiencies of the advanced drinking water treatment using ozonation process. For raw water, Nakdong River was used. By conducting batch test of ozonation, the following results were obtained. When ozone dosage of $5 mg/{\ell}$ was used, ozone transfer and utilization efficiencies of the ozonation were 94 to 92%, respectively. Removal efficiencies of single VOC compound or mixed VOC compounds in the raw water were 80% to 90% by the ozonation with $2 mg/{\ell}$ dosage and 10 minutes contact time. Removal efficiencies of ABS by the ozonation with $1 mg/{\ell}$, $3 mg/{\ell}$ dosage and 20 minutes contact time were 83% to 96%, respectively. Almost 67% of chlorophyll-a at the concentration of $38.4\mu\textrm{g}/{\ell}$ was removed by ozonation at ozone dosage of $1 mg/{\ell}$ for 20 min. Considering the efficiency of ozone utilization and water treatment, the most effective ozonation could be obtained with high ozone dosage and short contact time.