• KSTLE International Journal
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• 제2권1호
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• pp.17-21
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• 2001

Surface treatment technologies are frequently used to improve mechanical properties of surface layers of machinery components in many practical situations. Surface hardness of piston in the oil hydraulic piston pumps is very important about wear resistance. To improve hardness, wear resistance of the oil hydraulic axial piston pump, it is needed to know the surface layer characteristics in the sliding contact parts. This paper reports an experimental study on surface treatment characteristics in the piston of the oil hydraulic axial piston pump. We investigated the surface wear of a piston between untreated and nitriding-treated surfaces. We obviously observed that the surface hardness of piston in the oil hydraulic axial piston pump plays an important role to have wear resistance and remain a longer life.

• 약학회지
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• 제45권3호
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• pp.276-281
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• 2001

The present study was conducted to evaluate the effect of KST221085, a newly synthesized antidiabetic agent, on the hearts from streptozotocin (STZ)-induced diabetic rats. In isolated diabetic hearts, left ventricular developed pressure (LVDP), heart rate (HR) and coronary flow rate (CFR) were decreased compared to normal control, indicating cardiovascular dysfunction in diabetic heart. The treatment with 10 $\mu$M KST221085 remarkably improved the diabetes-induced contractile impairment, without any influence on HR. Reduced coronary flow in diabetic heart was also significantly increased by treatment with 10 $\mu$M KST221085. In isolated aorta from diabetic rat, treatment with 10 $\mu$M KST221085 increased endothelium-dependent relaxation, suggesting that KST221085 can improve the impaired endothelial function in diabetic aorta. Our results suggest that KST221085 treatment can improve the cardiovascular dysfunction in STZ-induced diabetic rats.

• Journal of Yeungnam Medical Science
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• 제37권2호
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• pp.84-89
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• 2020

Spinal pain is a common patient complaint in clinical practice. Conservative treatment methods include oral medication, physical therapy, injections, and spinal orthoses. The clinical application of orthoses is debated because of potential complications associated with long-term use, such as muscle weakness and joint contracture. We reviewed the orthoses most frequently used to manage spinal pain. We review the use of soft cervical and Philadelphia collars, lumbosacral corsets, and thoracolumbosacral orthosis to manage spinal pain. Spinal orthoses can help reduce pain by protecting the muscles and joints of the injured spinal region, preventing or correcting malformations, and limiting trunk flexion, extension, lateral flexion, and rotation. The short-term use of spinal orthoses is known to improve pain and disability during the treatment period without significant adverse effects. Spinal orthoses are expected to alleviate pain and improve patients' lifestyle.

• 한국염색가공학회지
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• 제14권1호
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• pp.43-50
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• 2002

Silk/Cotton fabrics were treated with butanetetracarboxylic acid(BTCA) to improve crease recovery and anti-shrinking properties at various curing temperatures and pH values. We investigated the effects of finishing conditions on add-on of BTCA, bending property(E, 2HB), wrinkle recovery angle, shrinkage, and dyeing properties. The Add-on of BTCA increased with increasing curing temperature and concentration. Crease recovery was improved with decreasing shrinkage. Maximum add-on of BTCA was showed at pH 2.5. In case of dyeing and mercerization, silk side treated with BTCA was more flexible than untreated, whereas cotton side was more stiff. In dyeing after mercerization, B and 2HB values were higher and K/S values were doubled nearly. The hand of fabric improved with decreasing B and 2HB by the BTCA treatment. BTCA treatment after reactive dyeing improved crease recovery, and caused no change of color difference. However, BTCA treatment after reactive dyeing didn't improve crease recovery, whereas B and 2HB were decreased considerably by the treatment.

• 한국운동역학회지
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• 제22권2호
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• pp.209-217
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• 2012

The purpose of this study was to develop a turn-type treatment program which applies the principle of spotting and a roll-type treatment program that induces off-vertical axis. 29 collegiate students volunteered for this study. 12-week treatment programs were applied to both 15 students for turn-type treatment group and 14 students for roll-type treatment group. As an analytic tool, eye camera was employed to verify the treatment programs for a stimulus upon a turn, recovery after a stimulus upon a turn, and nystagmus that affects a vestibular system. Two-way ANOVA with repeated measures was applied to see the significant differences between the treatment groups, and between the test periods. For Post-Hoc Test, paired t-test was used to within the group and independent t-test was used to between the groups. The results indicated that roll-type treatment training has maximized a stimulus on nystagmyus during the stimulus by a roll. Turn-type treatment training has maximized a stimulus on nystagmyus right after a stimulus by a roll and significantly decreased the intensity of nystagmyus during the recovery. Both turn and roll type treatments have reduced the recovery time which from nystagmyus to a normal status. Roll-type treatment has showed a much shorter recovery time for nystagmyus than the roll-type treatment has. Based on the results of treatment programs developed in this study, we expect the treatment programs can be applied to treat dizziness and to improve the function of vestibular system as a rehabilitation tool.

• Environmental Engineering Research
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• 제23권2호
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• pp.136-142
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• 2018

The river water source of Saidabad Surface Water Treatment Plant at Dhaka, Bangladesh, is deteriorated too much to be treated by conventional treatment process due to excessive ammonia pollution. In order to improve the raw water quality before it enters into the main treatment chain, a pilot study was conducted for pre-treatment of the raw water. The objective is to investigate the rate of reduction of ammonia using the Meteor pilot, a biological pretreatment system, which is a laboratory scale Moving Bed Biofilm Reactor with a nominal volume of hundred liters, filled with 50 L of Meteor 660 media. The reduction of ammonia was quite significant on average 73%, while the reduction of COD was in a range from 20 to 60%. The Meteor pilot was able to treat and nitrify the raw water and produce an effluent that respects the guarantee of ammonia < $4.0mg\;NH_3-N/L$ when the raw water ammonia concentration was < $15mg\;NH_3-N/L$. The study identified operating parameters necessary to achieve the desired goal of adequate ammonia removal. The study results would benefit a range of systems across the country by providing guidance on the design and operation of a biological pre-treatment system for ammonia removal.

• 대한치과기공학회지
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• 제39권1호
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• pp.55-65
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• 2017

Purpose: The study has been undertaken on several factors that may influence on the orthodontic treatment satisfaction with the subject of male and female university students who have experience in receiving the orthodontic treatment by visiting orthodontic clinic. Methods: This study has implemented questionnaire survey for 350 male and female university students who have experience in receiving the orthodontic treatment by visiting orthodontic clinic due to the mall occlusion, From the 350 questionnaires collected, a total of 291 copies (83.1%) excluding the questionnaires that have inconclusive response or erroneous response is used as the research analysis data Results: The orthodontic treatment satisfaction is significantly higher for students in large cities and mid- to small sized cities than students in rural area, and it was higher for students with mid-economic class that students of upper class and lower class. It is shown for a student that began the orthodontic treatment from the elementary school, a student that had 5 times or more of brushing teeth for each day had significantly higher level of satisfaction that students that are not. In addition, a student that knows well of the oral hygiene management method, a student that had the fluoride application treatment during the orthodontic treatment period and a student that used the toothbrush for orthodontic service had significantly higher level of satisfaction that students that are not. Conclusion: Factors influencing on the orthodontic treatment satisfaction are very diverse and it is considered that it requires effort to improve the quality of medical service and sufficient understanding on several factors to improve the orthodontic treatment satisfaction for patients as well as the encouragement for orthodontic treatment patients of the relevant people in orthodontic clinics that provide the orthodontic clinic service.

• 한국정밀공학회지
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• 제20권7호
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• pp.26-35
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• 2003

This study explains the effects of lubricant and surface treatment on hot forging die life. The mechanical and thermal load, and thermal softening which is happened by the high temperature of die, in hot and warm forging, cause die wear, heat checking and plastic deformation, etc. This study is fur the effects of solid lubricants and surface treatment condition for hot forging die. Because cooling effect and low friction are essential to the long life of dies, optimal surface treatment and lubricant are very important to improve die life for hot forging process. The main factors, which affect die hardness and heat transfer, are surface treatments and lubricants, which are related to thermal diffusion coefficient and heat transfer coefficient, etc. For verifying these effects, experiments are performed for hot ring compression test and heat transfer coefficient in various conditions as like different initial billet temperatures and different loads. The effects of lubricant and surface treatment for hot forging die life are explained by their thermal characteristics. The new developed technique in this study for predicting tool life can give more feasible means to improve the tool life in hot forging process.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 초전도 자성체 연구회
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• pp.25-29
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• 2003

Pre-treatment of Bi-2223/Ag tapes has been investigated to improve the superconducting property and grain alignment. However, rolling deformability of Bi-2223/Ag wires was degraded by the breakage of Ag alloy sheath after pre-treatment. Various pre-treatment conditions were tried to prevent the problem of sliver sheath and improve the superconducting property of Bi-2223/Ag tapes. Filament precursor of Bi-2223/Ag tapes was modified to be textured easily during main sintering by the optimum pre-treatment with low oxygen pressure and up to $800^{\circ}C$. Critical current was also increased up to 20% than that of no pre-treated tape.

• 펄프종이기술
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• 제32권2호
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• pp.40-44
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• 2000

A microscopic study was carried out to get the fundamental informations for the ozone deinking technology. The differential interference microscopic observation showed that ozone treatment was helpful to detach the toner ink from the surface of pulp fiber. The modifications of fiber surfaces by ozone treatment were observed with scanning electron microscope. Modification of fiber surfaces was not severe at the early stage of ozone treatment, but it increased with ozone treatment time and pulp consistency, Therefore, it would be possible to improve the properties of deinked pulp by controlling the condtion of ozone treatment.