• Journal of the Korean Society for Heat Treatment
• /
• v.29 no.6
• /
• pp.259-263
• /
• 2016

This study was carried out to investigate the effect of hot forging ratio on the microstructure and mechanical properties of incoloy 825 alloy. Hot forging was carried out at the forging ratio of 0%, 60% and 90% respectively in a range of $900^{\circ}C{\sim}1,140^{\circ}C$ and followed solution treatment was conducted at $1,000^{\circ}C$ for 1 hr. In all the specimens of hot forged of 0%, 60% and 90%, precipitates were not observed. The average grain size of 0% specimen is $82{\mu}m$ and that of 60% and 90% is $56{\mu}m$ and $31{\mu}m$, respectively. The range of grain size in the 0% specimen is uneven in $182{\mu}m$ to $31{\mu}m$, but the grain size of 90% specimen is uniform. With increasing hot forging ratio, the mechanical properties such as tensile strength, elongation, hardness increased and impact toughness increased by grain refinement.

• Fashion & Textile Research Journal
• /
• v.13 no.4
• /
• pp.635-643
• /
• 2011

This study was investigated to evaluate the physiological responses on T-shirts manufactured with selected functional materials by body parts which were selectioned on the distribution of sweating and temperature change. Seven healthy men in twenties were participated in a climate chamber of $27{\pm}0.5^{\circ}C$ and $50{\pm}1%RHC$. Three kinds of T-shirts named 'D1', 'D2' and 'Poly' were used as experimental clothings. Four kinds of functional materials of quick absorbing/drying were used in all section in 'D1', but two kinds of functional materials used partially in 'D2'. 'Poly' T-shirts used only polyester. In an experimental schedule of 90 minutes, which were consisted of 'Rest', twice of 'Exercise' and twice of 'Recovery' periods, the subjects walked on a treadmill with 60% of $VO_2max$. As a physiological responses, the microclimate temperature, surface temperature(skin, clothing) and sweat rate were measured. Temperature regulation was kept well in 'D1' rather than other T-shirts. The quick absorbing/drying T-shirts showed its performance well as the exercise goes on the second half. With these results in mind, 'D1' will be more effective for long hours exercise such as climbing rather than short hours exercise.

• Progress in Superconductivity and Cryogenics
• /
• v.9 no.1
• /
• pp.86-90
• /
• 2007

The cryoprobe used in cryosurgery should be fabricated in milimeter-order size for its practical usage. In general a miniature J-T(Joule-Thomson) refrigerator is applied to a cryoprobe. In case of the miniature J-T refrigerator, the mass flow rate of working fluid is small due to considerable friction in a minute flow path. For that reason, the miniature J-T refrigerator has a limited cooling power. To obtain the large cooling power from the J-T refrigerator, the refrigerator should have large mass flow rate and effective J-T temperature drop. These quantities are closely related to the geometry of the heat exchanger and the expansion nozzle in a cryoprobe, and are contradictory. The large mass flow rate leads to the small J-T temperature drop and vice versa in the miniature J-T refrigerator. Therefore, the optimal design of a cryoprobe to achieve maximum cooling power at fixed tube size and fixed operating temperature is required. This paper presents the design procedure of such case.

• Research in Community and Public Health Nursing
• /
• v.17 no.1
• /
• pp.83-90
• /
• 2006

Purpose: The present study purposed to investigate Korean adults health status, smoking perception. and self-efficacy of smoking cessation according to whether smoking or not. Methods: This study conducted a questionnaire survey of 694 adults at D County in Korea during the period from the 10th of June to the 10th of July 2004. The instruments used for this study were scales on health status, smoking perception and self-efficacy: of smoking cessation. Data was analyzed by frequency and percentage, mean and SD, $x^2-test$, t-test, ANOVA using SPSS 11.0 program. Results: The subjects of this study were 503 men and 191 women, and 60.8% of the male subjects and 6.8% of the female subjects were smokers. With respect to health status (t=-2.58, p=0.010), smoking perception (t=10.59. p<0.000) and the self-efficacy of smoking cessation (t=-23.04, p<0.000), there were significant differences according to whether smoking or not. Conclusions: It is necessary to make repeated study to find other variables that affect adults smoking and to develop smoking cessation programs that enhance the self-efficacy of smoking cessation.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.31A no.6
• /
• pp.88-97
• /
• 1994

We describe the design, fabrication, and performance of the optical fiber-photodiode 1$\times$12 arry module using mesa-type InS10.53T GaS10.47TAS/INP 1$\times$12 PIN photodiode array. We fabricated the PIN PD array for high-speed optical fiber parallel data link optimizing quantum efficiency, operating speed sensitivity from the PIN-FET structure, and electrical AC crosstalk. For each element of the array, the diameter of the photodetective area is 80 $\mu$m, the diameter of the p-metal pad is 90 $\mu$m, and the photodiode seperation is 250 $\mu$m to use Si v-groove. Ground conductor line is placed around diodes and p-metal pads are formed in zigzag to reduce Ac capacitance coupling between array elements. The dark current (IS1dT) is I nA and the capacitance(CS1pDT) is 0.9 pF at -5 V. No signifcant variations of IS1dT and CPD from element to element in the array were observed. We calulated the coupling efficiency for 10/125 SMF and 50/125 GI MMF, and measured the responsivity of the PD array at the wavelength is 1.55 $\mu$ m. Responsivities are 0.93 A/W for SMF and 0.96 A/W for MMF. The optical fiber-PD array module is useful in numerous high speed digital and analog photonic system applications.

• Journal of Hospice and Palliative Care
• /
• v.24 no.3
• /
• pp.154-164
• /
• 2021

Purpose: The purpose of this study was to examine the effects of a death preparation education program for nurses working in convalescent hospitals on death anxiety, death attitudes, and attitudes toward end-of-life care. Methods: This was a quasi-experimental study with a non-equivalent control group, pre-test and post-test design. Among 53 participants, 26 were assigned to the non-equivalent experimental group and 27 to the control group. The program was performed in the formats of lectures, video-watching, group discussions, and sharing, and consisted of 10 sessions held twice a week, for 5 weeks (90 minutes per session). Data were analyzed using descriptive statistics, the t-test, and the chisquare test in SPSS version 21.0. Results: Significant differences between the experimental and control groups were observed in death anxiety (t=7.62, P<0.001), death attitudes (t=-7.58, P<0.001), and attitudes to end-of-life care (t=-10.30, P<0.001). Conclusion: It was confirmed that the death preparation education program reduced death anxiety and had a positive effect on death attitudes and attitudes toward end-of-life care. Based on the results of this study, it is expected that specialized and systematic education that can increase the implementation and stability of death preparation education in various fields, including nursing, will have a positive effect on both hospice patients and members of society more broadly.

• Journal of muscle and joint health
• /
• v.29 no.2
• /
• pp.133-140
• /
• 2022

Purpose: This study was to examine the effects of auricular acupressure on competitive state anxiety and the accuracy of breaking in taekwondo players. Methods: This study was a quasi-experimental study with a time-series design. Twenty-two taekwondo breaking players were assigned to the control group for the first two weeks and then assigned to the experimental group for the next two weeks. Anxiety was measured by the revised Competitive State Anxiety Inventory-2 and the accuracy of breaking was measured as a percentage of breaking the wooden board. Results: Auricular acupressure for two weeks significantly increased the accuracy of breaking from 80.83±7.99% to 90.92±7.57% (t=7.74, p<.001). Auricular acupressure for two weeks significantly increased anxiety from 35.66±10.36 to 50.64±7.45 (t=4.38, p<.001). Among three subtypes of competitive state anxiety, somatic anxiety was increased from 12.48±4.97 to 22.95±4.54 (t=2.09, p=.011). Cognitive anxiety was significantly increased from 10.11±3.96 to 14.68±3.89 (t=5.37, p<.001) but self-confidence was not changed. Conclusion: The results of this study showed that auricular acupressure was effective in increasing the accuracy of breaking in taekwondo players.

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.4
• /
• pp.276-286
• /
• 2013

The goal of this study was to investigate change of thermal decomposition feature of miscanthus (Miscanthus sacchariflorus) after removal of inorganic constituents using distilled water (D.I-w; 30, 60 and $90^{\circ}C$). The carbon content was increased whereas the oxygen content was decreased with the temperature of D.I-w treatment. Moreover, ash content was slightly decreased from 4.6% of control to 3.2% of $90^{\circ}C$ D.I-w treated sample. Results of total monomeric sugar contents and X-ray diffraction (XRD) analysis showed that structural changes of cellulose/hemicellulose regions did not occurr during D.I-w treatment. Results of inductively coupled plasma emission spectrometer (ICP-ES) showed that miscanthus has the largest amount of inorganic constituents such as potassium (5,644 ppm), phosphorus (3,995 ppm), magnesium (1,403 ppm) and calcium (711 ppm). Thermogravimetric analysis (TGA) confirmed that the yield of char slightly decreased whereas the yield of volatiles increased with increasing D.I-w treatment temperature. In addition, differential thermogravimetric analysis (DTGA) indicated that the maximum decomposition rate ($V_M$) and temperature ($T_M$) corresponding to VM were varied from $0.82%/^{\circ}C$, $360.60^{\circ}C$ of control to $1.17%/^{\circ}C$, $362.62^{\circ}C$ of $90^{\circ}C$-D.I-w treated sample.

• Korean Journal of Radiology
• /
• v.22 no.8
• /
• pp.1332-1340
• /
• 2021

Objective: To evaluate the feasibility of a new three-dimensional (3D) MR fingerprinting (MRF) technique for the prostate gland by conducting phantom and clinical studies. Materials and Methods: The new 3D MRF technique used in this study enables quick data acquisition and has a high resolution. For the phantom study, the MRF T1 and T2 values in an in-house phantom were compared with those of goldstandard mapping methods using linear regression analysis. For the clinical study, we evaluated 90 patients who underwent prostate imaging with MRF for suspected prostate cancer between September 2019 and February 2020. The mean T1 and T2 values were compared in the peripheral zone, transition zone, and focal lesions using paired t tests. The differences in the T1 and T2 values according to cancer aggressiveness were evaluated using one-way analysis of variance. Results: In the phantom study, the MRF T1 and T2 values showed a perfect correlation with the gold-standard T1 and T2 values (R > 0.99). In the clinical study, the T1 and T2 values in the peripheral zone were significantly higher than those in the transitional zone (p < 0.001, both). The T1 and T2 values in prostate cancer were significantly lower than those in the peripheral and transitional zones. The higher the grade of cancer, the lower the T2 values. Conclusion: The T1 and T2 values obtained from the 3D MRF showed a perfect correlation with the gold standard values in the phantom study. Differences in the T1 and T2 values among the different zones of the prostate gland were identified using 3D MRF in patients.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.17
• /
• pp.7113-7118
• /
• 2014

Background: HSP90 may be overexpressed in cancer cells which are greatly dependent on Hsp90 function. Geldanamycin derivative 17 allylamino-17-demethoxygeldanamycin (17-AAG) inhibits the function and expression of HSP90. 17-AAG has poor water-solubility which is a potential problem for clinical practice. In this study for improving the stability and solubility of molecules in drug delivery systems we used a ${\beta}$-cyclodextrin-17AAG complex. Materials and Methods: To assess cytotoxic effects of ${\beta}$-cyclodextrin-17AAG complexes and free 17AAG, colorimetric cell viability (MTT) assays were performed. Cells were treated with equal concentrations of ${\beta}$-cyclodextrin- 17AAG complex and free 17AAG and Hsp90 gene expression levels in the two groups was compared by real-time PCR. Results: MTT assay confirmed that ${\beta}$-cyclodextrin- 17AAG complex enhanced 17AAG cytotoxicity and drug delivery in T47D breast cancer cells. The level of Hsp90 gene expression in cells treated with ${\beta}$-cyclodextrin- 17AAG complex was lower than that of cells treated with free 17AAG (P=0.001). Conclusions: The results demonstrated that ${\beta}$-cyclodextrin- 17AAG complexes are more effective than free 17AAG in down-regulating HSP90 expression due to enhanced ${\beta}$-cyclodextrin-17AAG uptake by cells. Therefore, ${\beta}$-cyclodextrin could be superior carrier for this kind of hydrophobic agent.