• Journal of the Korean Society for Heat Treatment
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• v.33 no.6
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• pp.277-283
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• 2020

Cu-Co-Si based alloy has a strengthening mechanism for Co₂Si intermetallic compounds deposited on the copper matrix after aging treatment and the solution treatment has a key influence on the strength and electrical conductivity of the final products. In this paper, the Cu-1.6%Co-0.38%Si alloy was fixed at the time and the solution treatment temperature was set at a temperature in the range of 800 to 950℃, and the change in mechanical properties was observed by fixing the temperature at 950℃ and changing the time. The microstructure was observed using an electron microscope and an optical microscope, and the changes in hardness, electrical conductivity, and bending workability after aging treatment were investigated. When the solution treatment time is less than 20 seconds, the solution treatment is not sufficient and the formation of precipitates contributing to the increase in hardness decreases and the hardness decreases after the aging treatment, and in more than 50 seconds, the hardness decreases due to the coarsening of the grains and the bending workability got worse.

• Korean Journal of Adult Nursing
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• v.12 no.3
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• pp.323-333
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• 2000

The purpose of this study was to determine the impact of situational, clinical and psychsoical factors on treatment-seeking behavior among those with acute myocardial infarction(AMI). This study used a retrospective, descriptive design. The sample consisted of 72 patients aged over 30 and who were diagnosed with an acute myocardial infarction at two large university-affiliated medical centers from July 1, 1998 to March 30, 2000. But of 72, patients 5 who were an outlier in treatment-seeking time were deleted. Data were collected by using questionnaires, which included demographic data, situational, clinical and psychosocial data. Also patient interviews and chart review were used to obtain information related to treatment-seeking time. The results of this study were summarized as follows ; 1. Mean time from the onset of AMI symptoms to arrival at the hospital was $12.09{\pm}11.44$ hours; 2. Treatment-seeking time was not significantly different by age, gender, or education; 3. Most(44 or 65.78%) patients were at home when they began having AMI symptoms. The remaining patients were either in a public area, workplace or in a car. Patients at home delayed longer than those who had their first symptoms elsewhere, but not significantly different. Also, most patients were with another person when they began to experience AMI symptoms: a spouse(25 or 37.3%), other family member(31 or 46.3%); the remaining 11 were alone. There were no significant differences in treatment-seeking time based on whether alone or with others. Most patients(46 or 68.7%) used an ambulance rather than taking private transportation, and patients who used an ambulance were delayed longer than those who used private transportation, but there were no significant differences; 4. Time to treatment-seeking was not significantly different by blood pressure, heart rate on admission and the peak CK-MB, CPK and Cholesterol level, Killips class; 5. There were no significant statistical differences in treament-seeking times by anxiety level, mood status or control ability.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.573-576
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• 2006

The efficacy of integrated ozone oxidation-biodegradation treatment was examined in the treatment of petrochemical wastewater with a special focus on the overall treatment time. When raw wastewater with chemical oxygen demand(COD) of 70-80 mg/L was oxidized by ozone, approximately 20% of initial COD was removed in less than 1.5 min at a dosing rate of 400 mg $O_3/L{\cdot}h $. No further decrease in COD was observed for the extended ozone treatment up to 30 min. Biological treatment alone showed a rapid reduction of COD to 40-50 mg/L, subsequently resulting in the decreased rate of COD removal. Pre-treatment by ozone before biological treatment did not significantly affect the specific rate of COD removal in a biological treatment. When ozone oxidation followed biological treatment, the extent of COD removal by ozone oxidation was greater compared to that of biologically-treated wastewater for a shorter time. Taken together, it was decided that the biological treatment time could be reduced if the treatment processes of concern will be properly arranged.

• The Journal of the Korean dental association
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• v.51 no.6
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• pp.346-354
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• 2013

Early identification of maxillary canine impaction is very important, because of treatment duration time. Analysis used by 3-dimensional computed tomography is more important than before in treatment planning. The aim of this study was to analysis of factors associated with the treatment during time of forced eruption of the impacted maxillary canine using 3-dimensional computed tomography. 17 patients were analysed in Daejeon dental hospital of Wonkwang university(16 patients with unilateral impactions and 1 patient with bilateral impaction). In total, 18 maxillary impacted cannines were analysed by 3-dimensional computed tomography. The results obtained were as follow; 1. There was positive correlation between the age of patient and treatment duration time. 2. There was positive correlation between the distance of occlusal plane to cusp of maxillary impacted canine and treatment duration time, and negative correlation between the length of maxillary impacted canine and treatment duration time. 3. There was positive correlation between the angulation of midsagittal plane to axis of maxillary impacted canine and treatment duration time, and negative correlation between occlusal plane to axis of maxillary impacted canine and treatment duration time. In conclusion, age, tooth length, distance from the canine cusp tip to the occlusal plane, angulation of tooth axis to occlusal plane and midsagittal plane allow that we can predict treatment duration time.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.11
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• pp.539-543
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• 2001

ln this paper, the $Sr_{l-x}Ca_xTiO_3(0\leqx\leq0.2)-based$ grain boundary layer ceramics were fabricated to measure dielectric properties with the sintering temperature and the thermal treatment time. The sintering temperature and time were $1420~15206{\circ}C$, 4hours, and the thermal treatment temperature and time of the specimen were $l150^{\circ}C$, 1, 2, 3hours, respectively. The structural and the dielectric properties were investigated by SEM, X-ray, HP4194A and K6517. The average grain size was increased with increasing the sintering temperature, but it decreased up to 15mo1% with increasing content of Ca. X-ray diffraction analysis results showed that all specimens were the cubic structure, and the main peaks were moved to right and the lattice constant were decreased with increasing content of Ca. The appropriate thermal treatment time and temperature of CuO to obtain dielectric properties of $\varepsilon_r>50000,\; tan \delta<0.05\; and \;\DeltaC<\pm10%$ were 2hrs and $l150^{\circ}C$, respectively.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.5
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• pp.438-443
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• 2021

This paper uses a multiplex deposition sputter system and aims to improve transmittance and reduce production costs by depositing a CdS thin film on an ITO glass substrate. When manufacturing CdS thin films, we wanted to find excellent conditions when manufacturing solar cells by changing heat treatment time. It was observed that thickness and sheet resistance were not significantly different depending on heat treatment time changes. The specific resistance was measured from a minimum of 6.68 to a maximum of 6.98. When the heat treatment time was more than 20 minutes, the transmittance was measured to be more than 75%. When the heat treatment time was 10 minutes, the bandgap was 3.665 eV and more than 20 minutes was 3.713 eV, which was measured as the same result. The XRD analysis showed that the structure of CdS was hexagonal and only CdS thin films were deposited without any other impurities. The result of calculating the FWHM was a maximum of 0.142 when the heat treatment time was 20 minutes, and a minimum of 0.133 when the heat treatment time was 40 minutes, so there was no significant difference in the FWHM when the heat treatment time was changed. The particle size was measured at 11.65 Å when the heat treatment time was 40 minutes, and at 10.93 Å when the heat treatment time was 20 minutes.

• Clinics in Shoulder and Elbow
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• v.19 no.2
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• pp.110-116
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• 2016

Background: Arthroscopic surgical repair is a better intervention than non-operative (conservative) treatment for patients with shoulder dislocations. This systematic review determined the numbers-needed-to-treat (NNT) and relative risk reduction (RRR) associated with arthroscopic surgical repair versus non-operative treatment in reducing recurrence rates among patients with first-time traumatic anterior shoulder dislocations. Methods: We searched Google Scholar, MEDLINE, SPORTDiscus, and CINAHL from inception in 2015. All articles had to compare arthroscopic surgical repair and non-operative treatment and be written in English. We used the total number of subjects and the number of recurrent dislocations within each treatment to calculate the NNT and RRR for each study and the pooled data. Results: Six articles were selected and all clearly demonstrated that the arthroscopic surgical repair was more effective than non-operative treatment in reducing the recurrence episodes. The pooled NNT was 1.76 (95% confidence interval [CI]=NNT to benefit 1.50-2.13) and the pooled RRR was 86.0% (95% CI=77.0%-92.0%) among individuals who underwent arthroscopic repair. The average follow-up time was 56 months. Conclusions: A Strength of Recommendation Taxonomy level of evidence of 1 with a grade A recommendation supports the use of arthroscopic surgical repair over non-operative treatment in prevention of first-time traumatic anterior shoulder dislocations. We suggest that sports medicine practitioners consider the patients' age, occupation, and physical activity level when making a clinical decision.

• Journal of the Korean institute of surface engineering
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• v.44 no.5
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• pp.220-225
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• 2011

304 stainless steel plate was colored by hot dip and electrochemical treatment in a solution containing sulphuric and chromic acids. In the process, treatment variables such as operating time and methode were changed. The surface characteristics that changed by the treatment of the samples such as surface composition, oxide film thickness, color, surface roughness and reflectivity were studied. Surface composition was varied as follows. Fe was decreased, but Cr and O were increased. Ni was increased until 20 min, but reveals decreasing tendency as time passed after that. These means the surface film becomes chrome rich oxide phase as the treatment times increase. The thickness of film was about 220 nm at 30 min by dip treatment and it reduced as the treatment times increased. On the other hand, the thickness was about 150 nm at 10 min by electrochemical method and it doesn't increased with time. Surface color changed from metallic white of the base plate to gray, black, red, and green-blue, gradually, as the treating time increased. The reflectivity of colored surface measured by UVVIS-NIR spectrophotometer was reduced from max 38% of basis metal to min 3.5%.

• Textile Coloration and Finishing
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• v.16 no.5
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• pp.28-34
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• 2004

The polarizing film application exploits the unique physicochemical properties between PVA(Poly vinyl alcohol) film and CTA(Cellulose triacetate) film. However, hardly any research was aimed at improving the adhesion characteristics of the CTA film by radio frequency(RF) plasma treatment at argon(Ar) gaseous state. In this report, we deal with surface treatment technology for protective CTA film developed specifically for high adhesion applications. After Ar plasma, surface of the films is analyzed by atomic force microscopy(AFM), roughness parameter and peel strength. Furthermore, the wetting properties of the CTA film were studied by contact angle analysis. Results obtained for CTA films treated with a glow discharge showed that this technique is sensitive to newly created physical functions. The roughness and peel strength value increased with an increase in treatment time for initial treatment, but showed decreasing trend for continuous treatment time. The result of contact angle measurement refer that the hydrophilicity of surface was increased. AFM studies indicated that no considerable change of surface morphology occurred up to 3 minutes of treatment time, but a considerable uneven of surface structure resulted from treating time after 5 minutes.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.4
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• pp.343-346
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• 1990

A study was conducted to determine the effect of prostaglandin $F_2$ alpha ($PGF_2$ alpha) on the reaction time and seminal characteristics of buffalo bulls. Semen was collected from three Murrah bulls in three periods: pre-treatment, treatment and post-treatment. During the treatment period each bull was administered 2 ml $PGF_2$ alpha (Synchrocept, Fenprostalene) im, 1 hour prior to semen collection. In the post-treatment, semen was collected 7 days after the last injection of $PGF_2$. Semen samples were evaluated immediately after collection. Pre-collection injection of $PGF_2$ alpha has no significant effect on reaction time, semen volume, percentage motility, sperm concentration and total number of sperms per ejaculate. Fluctuations in semen color and consistency were observed. There is a significant (p<0.05) increase in the mean percentage of normal spermatozoa during the treatment and post treatment periods. Likewise, administration of PG results into a significant (p<0.05) rise on the average percentage of live sperms but this effect was not manifested in the post-treatment period. Improvement in mass activity was observed during the treatment and post-treatment periods.