• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.65-67
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• 2003

The critical current of Bi-2223/Ag HTS wire could be improved by the second phase modification pre-treatment (SPMT). On the other hand, the pre-treatment conditions are possible to affect to the degradation of silver alloy sheath, such as brittleness. Chlorine was detected at the outer sheath of wire by Auger observation, we also have tried to search new pre-treatment conditions that do not affect the degradation of silver sheath but, improve the critical current of the wire.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.4
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• pp.412-420
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• 2000

A treatment should be functional, esthetic, conservative and periodontally healthy in order to meet criteria of an ideal dental procedure. In a prsthodontic patient with horizontal and/or vertical space deficiency, orthodontic tooth movement should be considered as a pre-prosthetic procedure. With a conventional technique, orthodontic treatment is a time-consuming and uncomfortable procedure. Pre-prosthetic orthodontic treatment, however, is no longer difficult procedure with the help of recently developed techniques, such as passive bracketing. The present article outlines the problems and causes of horizontal and vertical space deficiency in prosthodontic patients, and presents efficient pre-prosthetic orthodontic treatment modalities with typical clinical cases.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.3
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• pp.269-276
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• 2024

In response to the global interest and efforts towards reducing plastic use and promoting resource recycling, there is a growing need to establish methods for recycling discarded fishing gear. In Korea, various technologies are being developed to recycle discarded fishing gear, but significant technical and policy challenges still remain. In particular, biodegradable gill nets require a pre-treatment process to separate biodegradable materials from other substances and to remove salt before recycling. Therefore, this study aims to develop a pre-treatment device for recycling biodegradable gill nets and to evaluate the feasibility of recycling them.

• The Korean Journal of Emergency Medical Services
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• v.25 no.1
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• pp.7-22
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• 2021

Purpose: This study aimed to identify the differences in pre-hospital and in-hospital triage (pre-hospital triage and KTAS(Korean Triage and Acuity Scale)) of patients with abdominal pain and the characteristics of high hospitalization probability in the treatment results. Methods: We analyzed 941 people who visited the area C emergency center for 2 years from January 2017 to December 2018. The collected data were analyzed using SPSS 26. Results: Among the transfer hospitals, 84.8% (798) of patients were selected by the 119 rescue service, and the most common diagnosis was simple abdominal pain (46.5%, 438 patients). A total of 50.7% (477) of patients classified as severe pre-hospital cases changed to mild in-hospital cases. There was a difference of 5.3% (50 cases) in cases where patients classified as mild pre-hospital were changed to severe in-hospital cases. The Kappa coefficient did not match with 0.04 (p=.051). Pre-hospital overtriage was 58.2% (548 cases), and 71.2% (670) of patients were discharged from the emergency room as a result of the treatment. Conclusion: The results of this study showed that pre-hospital and in-hospital triage were not consistent. The rates of pre-hospital overtriage were quite high. Most patients with abdominal pain were classified as mild cases, and pre-hospital triage classifiers should be trained to reduce errors in selecting transfer hospitals.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.2
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• pp.104-116
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• 1996

Anaerobic digestion is generally used for the treatment of volatile organic solids such as manure and sludge from waste water treatment plants. However, the reaction rate of anaerobic process is slow, and thus it requires a large reactor volume. To minimize such a disadvantage, physical and chemical pre-treatment is generally considered. Another method to reduce the reactor size is to adopt different reactor system other than CSTR. In this paper, the effects of heat pre-treatment and reactor configurations on the anaerobic treatability of volatile solids was studied. Carrot, kale, primary sludge, and waste activated sludge was chosen as the test materials, and the BMP method was used to evaluate the maximum methane production and first order rate constants from each sample. After the heat treatment at $130^{\circ}C$ for 30min., the measured increase in SCOD per gram VS was up to 394 mg/L for the waste activated sludge. However, the methane production potential per gram VS was increased for only primary and waste activated sludge by 17-23%, remaining the same for carrot and kale. The overall methane production process for the tested solids can be described by first order reactions. The increased in reaction constant after heat pre-treatment was also more significant for the primary and waste activated sludge than that for carrot and kale. therefore, the heat pre-treatment appeared to be effective for the solids with high protein contents rather than for the solids with high carbohydrate contents. Among the four reactor systems studied, CSTR, PFR, CSTR followed by PFR, and PFR with recycle, CSTR followed by PFR appeared to be the best choice considering methane conversion rate and the operational stability.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.11a
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• pp.36-36
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• 1998

• The Journal of Advanced Prosthodontics
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• v.8 no.5
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• pp.339-344
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• 2016

PURPOSE. Pre-surface treatments of coping materials have been recommended to enhance the bonding to the veneering ceramic. Little is known on the effect on shear bond strength, particularly with new coping material. The aim of this study was to investigate the shear bond strength of veneering ceramic to three coping materials: i) metal alloy (MA), ii) zirconia oxide (ZO), and iii) lithium disilicate (LD) after various pre-surface treatments. MATERIALS AND METHODS. Thirty-two (n = 32) discs were prepared for each coping material. Four pre-surface treatments were prepared for each sub-group (n = 8); a) no treatment or control (C), b) sandblast (SB), c) acid etch (AE), and d) sandblast and acid etch (SBAE). Veneering ceramics were applied to all discs. Shear bond strength was measured with a universal testing machine. Data were analyzed with two-way ANOVA and Tukey's multiple comparisons tests. RESULTS. Mean shear bond strengths were obtained for MA ($19.00{\pm}6.39MPa$), ZO ($24.45{\pm}5.14MPa$) and LD ($13.62{\pm}5.12MPa$). There were statistically significant differences in types of coping material and various pre-surface treatments (P<.05). There was a significant correlation between coping materials and pre-surface treatment to the shear bond strength (P<.05). CONCLUSION. Shear bond strength of veneering ceramic to zirconia oxide was higher than metal alloy and lithium disilicate. The highest shear bond strengths were obtained in sandblast and acid etch treatment for zirconia oxide and lithium disilicate groups, and in acid etch treatment for metal alloy group.

• Journal of Welding and Joining
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• v.17 no.2
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• pp.61-65
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• 1999

Because of the need for packages which accommodate high pin count, high density and high speed device, PBGA(plastic ball grid array) package gets more spotlight. But the substrate material which is used for PBGA package is in nature susceptible to moisture penetration. The objective of the study is to find out the path of delamination in the stacked structure of substrate. To increase the adhesion between the cooper laminate and PSR(photo solder resist) which is the weakest part, experiments were performed by changing parameters of printing pre-treatment and post-treatment process. As a result of experiments, the factor effects on the adhesion between the cooper laminate and PSR is caused by all of the pre-treatment and post-treatment condition. A considerable change was observed depending on the amount of UV irradiation after thermal cure which is typical of printing post-treatment condition rather than pre-treatment condition.

• Textile Coloration and Finishing
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• v.18 no.4
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• pp.1-10
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• 2006

Tannin treatment has been used for improving the color fastness of dyed materials. In natural dyeing, the tannin treatment is highly effective in improving the fastness. The chitosan treatment also improves the fastness and depth of shade in natural dyeing. In this study, the effects of tannin and chitosan pre-treatment on the color and fastness in loess dyeing were investigated. Cotton woven fabric specimens and cotton knit fabric specimens were pre-treated with chitosan solution in acetic acid, and the specimens were then treated with or without tannin. The specimens were finally dyed with loess. The tannin treatment decreased the K/S values, while the chitosan treatment increased the K/S. Both the tannin treatment and the chitosan treatment increased the wash fastness and light fastness. In tannin treatment, tannin component and Fe component of loess may react together to decrease the lightness and develop dark color. For maintaining inherent color of the loess, it is much preferable to employ chitosan treatment rather than tannin treatment.

• Journal of Environmental Science International
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• v.14 no.7
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• pp.683-689
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• 2005

The consecutive combination process of a biological process as the pre-treatment and a chemical process as the post-treatment is applied for the dyeing wastewater. The poor efficiency of biological treatment using pure oxygen makes the chemical treatment cost high. It is necessary to improve the efficiency of biological treatment in order to reduce the cost of chemical treatment. The purpose of this paper is to find the minimum dose of chemical reagent to fit the Discharged Water Quality Standards for the different biological treatment effluents. Results revealed that the minimum dosage of Fenton's reagent lead to save the cost of chemical treatment based on the guideline dose in the treatment plant. The possible maximum saving reagents was up to $70\%$ for the effluent of the pilot plant packed with the carrier imbedded microorganisms which were selected from the present treatment plant.