• Journal of the Korean Society for Heat Treatment
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• v.17 no.5
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• pp.278-282
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• 2004

Effect of pre-treatment on the gas nitriding process of austenitic stainless steels has been investigated and the following results were obtained. Minimum pre-treatment time was decreased to 5min with increasing treatment temperature from $200^{\circ}C$ to $600^{\circ}C$. Surface activation effect by the pre-treatment was maintained in the air up to holding time of 64hr, judging from the analysis result of gas nitrided specimens. The Depth of nitrided layer of STS 304 and 316 stainless steels were ranged from $5{\mu}m$ to $90{\mu}m$ at $440^{\circ}C{\sim}600^{\circ}C$. The X-ray diffraction intensity for austenitic stainless steels were increases as nitriding temperature from $440^{\circ}C$ to $600^{\circ}C$.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.8 no.2
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• pp.5-17
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• 2002

The aim of study carried out to determine the effects of myofascial release on the cranial arteries velocity from November 11, 2001 to March 29, 2002 the objects were 10 patients who having the tension-type headache at H-hospital This research compared with measure the mean flow velocity middle cerebral artery, posterior cerebral artery, vertebral cerebral artery. Result obtain were as follows; 1. Middle cerebral artery blood velocity between pre treatment and after treatment for 10days experiment was significantly increased 9.76cm/s(p<0.05)in right, 4.88cm/s(p<0.05)in left. 2. Posterior cerebral artery blood velocity between pre treatment and after treatment experiment was difference 6.35cm/s(p<0.01)in right, 5.14cm/s(p<0.01)in left, between pre treatment and after treatment for 5days experiment was 11.48cm/s(p<0.01)in right, 10.74cm/s(p<0.01)in left, between pre treatment and treatment for 10days experiment was 12.92cm/s(p<0.001) in right, 12.68cm/s(p<0.001) in left. 3. Vertebral artery blood velocity between pre treatment and post treatment experiment was difference 4.48cm/s(p<0.05)in right, 6.10cm/s(p<0.05) in left, between pre treatment and after treatment for 5days experiment was 12.50cm/s(p<0.001)in right, 14.40cm/s(p<0.001)in left, between pre treatment and after treatment for 10days experiment was 14.70cm/s(p<0.001)in right, 13.90cm/s(p<0.001)in left.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.613-619
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• 2018

In this study, various influent sludge pre-treatment methods and the internal recirculation of thickened sludge from effluents using a liquid/solid separation unit were adopted to investigate their effects on the sludge digestion and methane production in a combined mesophilic anaerobic and thermophilic aerobic sludge digestion process. A lab-scale combined sludge digestion process was operated during 5 phases using different feed sludge pre-treatment strategies. In phase 1, the feed sludge was pre-treated with a thermal-alkaline method. In contrast, in phases 2, 3 and 4, the internal recirculation of thickened sludge from the effluent and thermal-alkaline, thermal, and alkaline pre-treatment (7 days) were applied to the combined process. In phase 5, the raw sludge without any pre-treatment was used to the combined process. With the feed sludge pre-treatment and internal recirculation, the experimental results indicated that the volatile suspended solid (VSS) removal was drastically increased from phases 1 to 4. Also, the methane production rate with the thermal-alkaline pre-treatment and internal recirculation was significantly improved, showing an increment to 285 mL/L/day in phase 2. Meanwhile, the VSS removal and methane production in phase 5 were greatly decreased when the raw sludge without any pre-treatment was applied to the combined process. Considering all together, it was concluded that the combined process with the thickened sludge recirculation and thermal-alkaline pre-treatment can be successfully employed for the highly efficient sewage sludge reduction and methane gas production.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.5
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• pp.655-659
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• 2005

Pre-filter system that was consisted of wasted-tire, non-woven fabrics, and sponge was developed as a primary treatment process prior to rainwater reservation or a pre-treatment process of rainwater reuse system for reclamation. By using this system, SS concentration, TOC, COD, and turbidity could decreased by 86.7%, 62.6%, 69.1% and 66.5%, respectively. From the results of particle size distribution of treated water, the particles over than $30{\mu}m$ of diameter were completely removed by pre-filter system. But 90% of particles less than $20{\mu}m$ of diameter were passed through pre-filter. Optimal depth of wasted-tire and non-woven fabrics were 15cm and 2.4cm, respectively. Pre-filter system was considered as an effective alternative for pre-treatment of rainwater including non-point pollutants and it could be also applied for the treatment of combined sewer overflow (CSO).

• Analytical Science and Technology
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• v.35 no.3
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• pp.129-135
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• 2022

We tested the pre-treatment of alumina, leucine, alumina mixed with leucine at ratios of 9:1 (Al-Leu (9:1)) and 5:1 (Al-Leu (5:1)), and alumina mixed with sodium lactate at a ratio of 5:1 (Al-Lac (5:1)) on aged fingerprints (1, 7, 14, and 30 days after natural fingerprinting) before cyanoacrylate (CA) fuming to improve the development efficacy. As a result of the experiment, fingerprints with pre-treatment of alumina, leucine, Al-Leu (9:1), Al-Leu (5:1), and Al-Lac (5:1) showed better development efficacy (area and minutiae) than fingerprints without pre-treatment. Therefore, this modified CA fuming method improved the development efficacy with five pretreatments.

• Radiation Oncology Journal
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• v.36 no.2
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• pp.122-128
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• 2018

Purpose: To investigate positional uncertainty and its correlation with clinical parameters in spine stereotactic body radiotherapy (SBRT) using thermoplastic mask (TM) immobilization. Materials and Methods: A total of 21 patients who underwent spine SBRT for cervical or upper thoracic spinal lesions were retrospectively analyzed. All patients were treated with image guidance using cone beam computed tomography (CBCT) and 4 degrees-of-freedom (DoF) positional correction. Initial, pre-treatment, and post-treatment CBCTs were analyzed. Setup error (SE), pre-treatment residual error (preRE), post-treatment residual error (postRE), intrafraction motion before treatment (IM1), and intrafraction motion during treatment (IM2) were determined from 6 DoF manual rigid registration. Results: The three-dimensional (3D) magnitudes of translational uncertainties (mean ${\pm}$ 2 standard deviation) were $3.7{\pm}3.5mm$ (SE), $0.9{\pm}0.9mm$ (preRE), $1.2{\pm}1.5mm$ (postRE), $1.4{\pm}2.4mm$ (IM1), and $0.9{\pm}1.0mm$ (IM2), and average angular differences were $1.1^{\circ}{\pm}1.2^{\circ}$ (SE), $0.9^{\circ}{\pm}1.1^{\circ}$ (preRE), $0.9^{\circ}{\pm}1.1^{\circ}$ (postRE), $0.6^{\circ}{\pm}0.9^{\circ}$ (IM1), and $0.5^{\circ}{\pm}0.5^{\circ}$ (IM2). The 3D magnitude of SE, preRE, postRE, IM1, and IM2 exceeded 2 mm in 18, 0, 3, 3, and 1 patients, respectively. No association were found between all positional uncertainties and body mass index, pain score, and treatment location (p > 0.05, Mann-Whitney test). There was a tendency of intrafraction motion to increase with overall treatment time; however, the correlation was not statistically significant (p > 0.05, Spearman rank correlation test). Conclusion: In spine SBRT using TM immobilization, CBCT and 4 DoF alignment correction, a minimum residual translational uncertainty was 2 mm. Shortening overall treatment time and 6 DoF positional correction may further reduce positional uncertainties.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.84-89
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• 2003

The purpose of this study was to evaluate and improve the pre-treatment facility for foodwaste and sewage sludge mixture treatment. The process of foodwaste pre-treatment consists of storage, classification with crushing, and thickening. The effluent of sewage treatment facility was used as the diluting and washing water. The panicle size of foodwaste after pre-treatment was almost under 2mm, the mixture of foodwastes and sewage sludge showed an advantage to the anaerobic digestion. The amount of gas production increased from 0.8ton/day ($CH_4$ : 0.5ton/day) to 3.5ton/day ($CH_4$ : 2.3ton/day) after the anaerobic digestion of the foodwastes and sewage sludge mixture. The amount of sludge cake increased from 11.2ton/day to 21.2ton/day. Therefore, the proper operation of the foodwaste pre-treatment facility was contributed to the efficient anaerobic digestion of foodwaste and sewage sludge mixture treatment.

• Tuberculosis and Respiratory Diseases
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• v.84 no.1
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• pp.74-83
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• 2021

Background: This study compared the treatment outcomes of patients with multidrug-resistant tuberculosis (MDR-TB) before and after the implementation of public-private mix (PPM). Factors affecting treatment success were also investigated. Methods: Data from culture-confirmed pulmonary MDR-TB patients who commenced MDR-TB treatment at Pusan National University Hospital between January 2003 and December 2017 were retrospectively reviewed. Patients were divided into two groups in terms of PPM status: pre-PPM period, patients who commenced MDR-TB treatment between 2003 and 2010; and post-PPM period, patients treated between 2011 and 2017. Results: A total of 176 patients were included (64 and 112 in the pre- and post-PPM periods, respectively). 36.9% of the patients were resistant to a fluoroquinolone or a second-line injectable drug, or both. The overall treatment success rate was 72.7%. The success rate of post-PPM patients was higher than that of pre-PPM patients (79.5% vs. 60.9%, p=0.008). Also, loss to follow-up was lower in the post-PPM period (5.4% vs. 15.6%, p=0.023). In multivariate regression analysis, age ≥65 years, body mass index ≤18.5 kg/m², previous TB treatment, bilateral lung involvement, and extensively drug-resistant (XDR)- or pre-XDR-TB were associated with poorer treatment outcomes. However, the use of bedaquiline or delamanid for ≥1 month increased the treatment success. Conclusion: The treatment success rate in MDR-TB patients was higher in the post-PPM period than in the pre-PPM period, particularly because of the low rate of loss to follow-up. To ensure comprehensive patient-centered PPM in South Korea, investment and other support must be adequate.

• Textile Coloration and Finishing
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• v.31 no.2
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• pp.88-97
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• 2019

In this study, when printed on a nylon material, the color strength and fastness are lower than that of a polyester material, and the nylon material shrinks due to heat and pressure, resulting in poor design and poor compatibility. To overcome this problem, we investigated the possibility of transfer DTP by adding pre-treatment process to nylon transfer DTP process. For the basic study of pre-treatment preparation, we used pure nylon material which is not compounded and dispersion ink and transfer paper applied to existing PET transfer DTP. Pre-treatment preparations were classified into three types of acryl-base polymer and pre-treated with nylon and then applied to transfer DTP to confirm their color strength and fastness. The color strength of the pre-treated nylon material increased and poly-methyl-acrylate amulsion pre-treatment showed the best color at $210^{\circ}C$, 1.5m/min and 0.3MPa. The nylon material pre-treated with washing, friction, and light fastness was judged to be more excellent and stable.

• Textile Coloration and Finishing
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• v.27 no.4
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• pp.318-326
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• 2015

A pre-treatment process is essential for getting high quality of digital textile printing(DTP). In this study, we have studied three kinds of carrageenan polymer(k-, ${\lambda}$-, i-Carrageenan) as a pre-treatment thickening agent for the first time. Alginate polymer was also examined and its results were compared with that of the three kinds of carrageenan polymer. To confirm the performance of each thickening agent, we examined for a sharpness, color strength and fastness(washing, rub, light). The result showed that ${\lambda}$-Carrageenan has superior property in sharpness with low viscosity and i-Carrageenan was excellent in the color strength among the pre-treatment agents. Washing fastness to color change and staining for the all samples were 4 or 4-5 grade. Both dry and wet rubbing fastness of the samples were 4-5 grade. However, ${\lambda}$-Carrageenan coated sample has the lowest grade in light fastness. As a result, we found the possibility of carrageenan polymer as pre-treatment agent.