• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.1
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• pp.717-724
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• 2020

In general, the factors affecting the heat transfer of asphalt pavement are divided into weather factors and pavement materials. Among them, material factors include the thermophysical and surface properties. An experiment was conducted on the thermal-physical factors of asphalt, which are the basis for the pavement failure model. The thermal conductivity, specific heat capacity, thermal diffusivity, and thermal emissivity were evaluated as the thermo-physical properties of asphalt. The specimens (WC-2 & PA-13) used in the experiment were compacted with a Gyratory Compactor. The experimental results of WC-2 and PA-13 showed a thermal conductivity of 1.18W/m·K and 0.9W/m·K, specific heat capacity of 970.8J/kg·K and 960.1J/kg·K, thermal emissivity of 0.9 and 0.91, and thermal diffusivity of 5.15㎡/s and 4.66㎡/s, respectively. Experiments on the heat transfer characteristics (thermo-physical properties) of asphalt pavement that can be used for thermal failure modeling of asphalt were conducted.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.41-45
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• 2006

The study on laser-ablation plasmas has been strongly interested in fundamental aspects of laser-solid interaction and consequent plasma generation. In particular, this plasma has been widely used for the deposition of thin solid films and applied to the semiconductors and insulators. In this paper, we developed and discussed the generation of carbon ablation plasmas emitted by laser radiation on a solid target, graphite. The progress of carbon plasmas by laser-ablation was simulated using Monte-Carlo particle model under the pressures of vacuum, 1 Pa, 10 Pa and 66 Pa. At the results, carbon particles with low energy were deposited on the substrate as the pressure becomes higher. However, there was no difference of deposition distributions of carbon particles on the substrate regardless of the pressure.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.406-413
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• 2000

The friction and wear behaviors of Magnetron Sputtered MoS$_2$films were investigated by using a pin on disk type tester which was designed and manufactured for this experiment. The experiment was conducted by using silicon nitride (Si$_3$N$_4$) as a pin material and Magnetron Sputtered MoS$_2$on bearing steel (STB2) as a disk material, under operating conditions that include different surface roughness (Polishing specimen, Grinding specimen)(2types), linear sliding velocities in the range of 22, 44, 66mm/sec (3types), normal loads vary from 9.8N, 19.6N, 29.4N(3types), corresponding to contact pressures of 1.9∼2.7GPa and atmospheric conditions of high vacuum( 1.3${\times}$10$\^$-4/Pa), medium vacuum( 1.3${\times}$10$\^$-l/Pa), ambient air(10$\^$5/Pa)(3types). We investigated fracture mechanism in magnetron sputtered MoS$_2$films with Magnetron Sputtering method in each experiment.

• Journal of the Ergonomics Society of Korea
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• v.28 no.3
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• pp.95-102
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• 2009

Ten young females were participated in this study to investigate the effects of types of shoes (sneakers, high heels, kill heels), types of tasks (standing, walking floor, step up and down), and areas of foot (fore foot, middle foot, rear foot) on foot pressures as well as subjective discomfort ratings. Results showed that kill heels had the most discomfort shoes, followed by high heels and sneakers. Generally, as the heel was higher, the discomfort of foot increased. For the analyses of task types, generally discomfort ratings were highest for the step down and up, followed by walking floor and standing. Especially discomfort ratings of high heels and kill heels were more evident in case of step up and step down than standing and walking floor. Standing task was rated as the lowest levels of discomfort on users' foot. Peak and mean foot pressures were also evaluated in this study. The findings represented that there was no significant differences between types of shoes in both peak and mean foot pressures. The peak pressure (82.14kPa) and mean pressure (40.32kPa) for standing task were significantly lower than those of other tasks [walking floor (190.55kPa, 55.46kPa), step up (191.43kPa, 53.80kPa), and step down (200.66kPa, 52.62kPa)]. Generally discomfort ratings and peak/mean pressures associated with foot showed that fore foot had higher discomfort ratings as well as peak and mean pressures than middle and rear foots. In particularly, this trend was more obvious in case of high heels and kill heels. For the high heels and kill heels, the peak pressures of fore foot were 4.5~4.8 times and 2.3~2.5 times greater than that of middle foot and rear foot, respectively, whereas the peak pressures of fore foot were 2.9 times and 1.7 times greater than that of middle and rear foots, respectively, in case of sneakers.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.6
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• pp.60-66
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• 1992

This study describes a theoretical analysis for the wall temperature of ceramic filter trap and pressures of inlet and outlet channel in the filter trap. In this study, the maximum wall temperature through filter trap length with time during the regeneration period showed a tendency moving from forward to backward. The pressure change of filter trap increased at the initial combustion but decreased with the combustion to be activated. So the pressure difference between initial and end regeneration at the inlet channel showed about 2kPa. The thermal regeneration period of this filter trap in the theoretical analysis showed about 200seconds in which the wall temperature was similar to the case of initial condition and the pressure showed about 1 kPa.

• Membrane and Water Treatment
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• v.10 no.6
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• pp.431-440
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• 2019

A novel composite membrane was synthesized using crosslinked polyamide and fly ash ceramic substrate for phenol removal. Glutaraldehyde was used as crosslinker. Characterization shows that synthesized membrane possesses good permeability ($0.184l.m^{-2}.h^{-1}.kPa^{-1}$), MWCO (1.7 kDa), average pore size (1.08 nm) and good chemical stability. RSM was adopted for phenol removal studies. Box-Behnken-Design using quadratic model was chosen for three operating parameters (feed phenol concentration, pH and applied pressure) against two responses (phenol removal, flux). ANOVA shows that model is statistically valid with high coefficient of determination ($R^2$)value for flux (0.9897) and phenol removal (0.9302). The optimum conditions are obtained as pH 2, $46mg.l^{-1}$ (feed phenol concentration) and 483 kPa (applied pressure) with 92.3% phenol removal and $9.2l.m^{-2}.h^{-1}$ flux. Data validation with deviation of 4% confirms the suitability of model. Obtained results reveal that prepared composite membrane can efficiently separate phenol from aqueous solution.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.11
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• pp.4863-4865
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• 2016

Background: Prostatic adenocarcinoma by Prosate cancer (PCa) is the most prevalent cancer and the second cause of cancer-related death among men in the Western world. Human papilloma virus (HPV) may be considered as a preventable risk factor. In this study, we assessed the frequencies of HPV infection in prostatic adenocarcinoma and benign prostatic hyperplasia (BPH) cases in Northeast Mexico. Materials and Methods: A total of 87 paraffin-embedded blocks (from 25 and 62 patients with definite diagnoses of BPH and adenocarcinoma, respectively) were selected and subjected to INNOLiPA HPV Genotyping to detect 28 high- and low-risk HPV types. The rates of infection were compared in the two studied groups. Results: INNOLiPA HPV demonstrated great sensitivity for HPV detection on paraffin-embedded tissue. Global prevalence was 14.9% (13/87). HPV infection was positive in 19.4% (12/62) of patients with adenocarcinoma and 4.0% (1/25) of patients with BPH. HPV-11, which is considered to be low risk, was more prevalent. Interestingly, one patient with BPH and six with prostate cancer showed examples considered to be high risk (HPV-18, -51, -52, and -66). Conclusion: A higher rate of HPV infection among Mexican patients with prostatic carcinoma than among those with BPH was observed. HPV infections may thus contribute to the risk of prostate cancer. Further studies are required to elucidate any roles of HPV infection in prostate disease in Mexico and the effect of prevention and treatment of HPV infection on prostatic adenocarcinoma.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.55-66
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• 2022

In this study, forty corrugated fiberboard (CF) boxes for fresh produce were collected from farms located in Gyeongsan city and evaluated its characterizations and physical properties according to Korean Standard (KS). The basis weight, flute, and paperboard combination were determined for the characterizations of CF boxes. The measured basis weights of all samples were within the tolerance limit referred to KS and the flutes were B/F, EB/F, and AB/F flute, respectively. The bursting strength (BS), edgewise crush resistance (ECR), and compression strength (CS) were tested to evaluate the physical properties. There are four single-walled (SW) CF boxes showed BS and ECR higher than 638 kPa and 3.30 kN/m, respectively. One SW CF boxes showed BS and ECR higher than 785 kPa and 3.43 kN/m, respectively. In case of double-walled (DW) CF boxes, sixteen CF boxes showed BS and ECR higher than 785 kPa, 4.96 kN/m (AB flute), or 4.90 (EB flute), respectively. The other nineteen CF boxes showed BS and ECR higher than 981 kPa, 5.29 kN/m (AB flute), or 5.20 (EB flute), respectively. All the CF boxes except two samples showed the acceptable compression strength in reference to the guideline of KS.

• Clinical and Experimental Reproductive Medicine
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• v.50 no.3
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• pp.192-199
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• 2023

Objective: This study was conducted to investigate chromosomal abnormalities and their correlations with clinical and radiological findings in females with primary amenorrhea (PA). Methods: Detailed forms were recorded for 470 females, including the construction of three-generation pedigrees. Peripheral venous blood was drawn, with informed consent, for cytogenetic analysis. Results: An abnormal karyotype was found in 16.38% of participants. The incidence of structural abnormalities (6.8%) exceeded that of numerical abnormalities (6.15%). Turner syndrome represented 45% of all numerical abnormalities. Furthermore, the Y chromosome was detected in 5% of females with PA. Among the structural chromosomal abnormalities detected (n=32) were mosaicism (25%), deletions (12.5%), isochromosomes (18.75%), fragile sites (3.12%), derivatives (3.12%), marker chromosomes (3.12%), and normal variants (29.125%). An examination of secondary sexual characteristics revealed that 29.6% of females had a complete absence of breast development, 29.78% lacked pubic hair, and 36.88% exhibited no axillary hair development. Radiological findings revealed that 51.22% of females had a hypoplastic uterus and 26.66% had a completely absent uterus. Abnormal ovarian development, such as the complete absence of both ovaries, absence of one ovary, one absent and other streak, or both streak ovaries, was observed in 69.47% of females with PA. Additionally 43.1%, 36.1%, 67.4%, and 8% of females had elevated levels of serum follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, and prolactin, respectively. Conclusion: This study underscores the importance of karyotyping as a fundamental diagnostic tool for assessing PA. The cytogenetic correlation with these profiles will aid in genetic counseling and further management of the condition.

• Polymer(Korea)
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• v.36 no.6
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• pp.677-684
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• 2012

Injection molding process is a popular polymer processing involving plasticizing and enforcing the material flow into the mold. A polymer material shrinks according to temperature variations during the shaping process, and subsequently molding shrinkage developed. Developed deflections or warpages after molding process in part are caused by residual stress relaxation contained in the part. Adding inorganic materials or fibers such as glass and carbon to control shrinkage and enhance warpage resistance are common. In this study, warpages according to part design have been investigated through experiment. Warpages for molding conditions and mold designs such as gate locations were measured. Warpages along flow direction and perpendicular to the flow direction were also measured. Warpages near gate and far from gate were compared. Glass fiber reinforced crystalline polymers, PP and PA66 have been used in this experiment. Glass fiber reinforced crystalline polymers showed large warpage compared with glass reinforced amorphous polymers. Warpages in crystalline polymers were less influenced by molding conditions compared with amorphous polymers, however warpages of crystalline polymers significantly depend on part design.