• Journal of the Korean Society for Heat Treatment
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• v.19 no.5
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• pp.249-256
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• 2006

Structural studies have been performed on precipitation hardening found in $L1_2$ ordered ${\gamma}^{\prime}-Ni_3(Al,Ti)$ alloys using transmission electron microscopy. A uniform solid solution of ${\gamma}^{\prime}-L1_2$ ordered phase supersaturated with Ni can be obtained by solution annealing in a suitable temperature range. The ${\gamma}^{\prime}$ phase hardens appreciably by the fine precipitation of disordered ${\gamma}$. The shape of ${\gamma}$ precipitates formed during aging is initially spherical or round-cubic and grow into platelets as aging proceeds. High resolution electron microscopy revealed that the ${\gamma}$ precipitates are perfectly coherent with the matrix ${\gamma}^{\prime}$ as long as the ${\gamma}$-precipitates are plates. The loss of coherency initiates by the introduction of dislocations at the ${\gamma}/{\gamma}^{\prime}$ interface followed by the step formation at the dislocations. The ${\gamma}$ precipitates become globular after the loss of coherency. The strength of ${\gamma}^{\prime}-Ni_3(Al,Ti)$ increases over the temperature range of experiment by the precipitation of fine ${\gamma}$ particles. The peak temperature where a maximum strength was obtained shifted to higher temperature.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.2
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• pp.96-102
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• 1994

The present work was aimed to examine the changes of the shape and particle size distribution(PSD) of ${\delta}^{\prime}$ particles on ageing in Al-Li-(Cu, Zr) alloys which had low density, high specific strength and stiffness, Increasing ageing time and temperature resulted in particles whose aspect ratio tended toward 1. The aspect ratio of ${\delta}^{\prime}$ particles was not dependent upon the ageing temperature and time in Al-Li-Cu alloy but was dependent upon them in Al-Li-Zr alloy. The PSD of ${\delta}^{\prime}$ particles in Al-Li-Zr alloy skewed to the right hand compared with that in Al-Li-Cu alloy, because $Al_3Zr$ phase in Al-Li-Zr alloy formed before ageing promoted the precipitation and growth of ${\delta}^{\prime}$ phase. Therefore, the PSD of the ${\delta}^{\prime}$ particles was found to be affected by the presence of $Al_3Zr$ particles. The growth rate of ${\delta}^{\prime}$ phase was not affected by the existence of the third transition phase $T_1$ formed by the addition of Cu in Al-Li alloy but was affected by the existence of $Al_3Zr$ formed by the addition of Zr in Al-Li alloy.

• Journal of the Korean Society for Heat Treatment
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• v.8 no.1
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• pp.65-74
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• 1995

This research was performed to investigate the effect of ageing on grain refinement of 82wt%Cu-13.5wt%Al-4.5wt%Ni-0.1wt% misch metal alloy with ageing temperature and time. The results obtained in this study are as follows; The variation of transformation temperature with ageing temperature had very influence on ageing time at $300^{\circ}C$. But it had not influence on ageing time at $100^{\circ}C$. The variation of transformation temperature after second reversed transformation cycle was not occured in martensitic phase ageing, but $M_s$ point was appeared equally with third reversed transformation cycle in parent phase ageing. The variation of $M_s$ point was not nearly with ageing time at $100^{\circ}C$ ageing temperature. But it was decreasing with ageing time at $300^{\circ}C$ ageing temperature and $A_s$ point was increasing with ageing time. Structure of parent phase ageing was being M18R martensitic and N2H martensitic phase. It was found that ${\alpha}$ and ${\gamma}_2$ phase were created by ageing of long time at $300^{\circ}C$ ageing temperature.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.7
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• pp.1003-1008
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• 2012

One hundred and twenty weanling pigs in experiment 1 (Exp. 1) ($6.91{\pm}0.99kg$; 21 d of age) and Exp. 2 ($10.20{\pm}1.09kg$; 28 d of age) were used in two 42-d and 35-d experiments to evaluate the effect of medium-chain-triglyceride (MCT) on growth performance, apparent total tract digestibility (ATTD) of nutrients and blood profile. In both of Exp. 1 and Exp. 2, the same dietary treatments were utilized as follows : i) negative control (NC), ii) positive control (PC), NC+antibiotics (40 mg/kg Tiamulin, 110 mg/kg Tylosin, and 10 mg/kg Enramycin, iii) MCT3, NC+0.32% (phase 1, 2 and 3) MCT, and iv) MCT5, NC+0.55% (phase 1), 0.32% (phase 2 and 3) MCT. In Exp. 1, the pigs fed MCT5 diets had higher (p<0.05) ADG compared to NC treatment during the first 2 wk. From d 15 to 28, the ATTD of energy was improved (p<0.05) by MCT3 compared to the PC treatment. No effect has been observed on the blood profiles [red blood cell (RBC), white blood cell (WBC), immunoglobulin-G (IgG), lymphocyte concentration] measured in this study. In Exp. 2, the ADG were increased (p<0.05) by the MCT5 treatment than the PC treatment from d 0 to 14. Pigs fed PC treatment diet had lower ADFI (p<0.05) and better FCR (p<0.05) than NC treatment, whereas no differences were shown between MCT treatments and NC or PC treatment from d 15 to 35 and overall phase. The ATTD of DM and nitrogen were improved (p<0.05) by the effect of MCT5 related to the NC and PC treatment at the end of 2nd and 5th wk. The pigs fed MCT3 had higher (p<0.05) energy digestibility than PC treatment. No effects were seen in the blood profiles we measured (WBC, RBC, lymphocyte and immunoglobulin-G). In conclusion, the addition of MCT in the weanling pigs diet can improve the ADG and digestibility during the earlier period (first 2 wks), but had little effect on the blood characteristics.

• Journal of Korean Neurosurgical Society
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• v.67 no.4
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• pp.451-457
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• 2024

Objective : Exploring protein requirements for critically ill patients has become prominent. On the other hand, considering the significant impact of coma therapy and targeted temperature management (TTM) on the brain as well as systemic metabolisms, protein requirements may plausibly be changed by treatment application. However, there is currently no research on protein requirements following the application of these treatments. Therefore, the aim of this study is to elucidate changes in patients' protein requirements during the application of TTM and coma therapy. Methods : This study is a retrospective analysis of prospectively collected data from March 2019 to May 2022. Among the patients admitted to the intensive care unit, those receiving coma therapy and TTM were included. The patient's treatment period was divided into two phases (phase 1, application and maintenance of coma therapy and TTM; phase 2, tapering and cessation of treatment). In assessing protein requirements, the urine urea nitrogen (UUN) method was employed to estimate the nitrogen balance, offering insight into protein utilization within the body. The patient's protein requirement for each phase was defined as the amount of protein required to achieve a nitrogen balance within ±5, based on the 24-hour collection of UUN. Changes in protein requirements between phases were analyzed. Results : Out of 195 patients, 107 patients with a total of 214 UUN values were included. The mean protein requirement for the entire treatment period was 1.84±0.62 g/kg/day, which is higher than the generally recommended protein supply of 1.2 g/kg/day. As the treatment was tapered, there was a statistically significant increase in the protein requirement from 1.49±0.42 to 2.18±0.60 in phase 2 (p<0.001). Conclusion : Our study revealed a total average protein requirement of 1.84±0.62 g during the treatment period, which falls within the upper range of the preexisting guidelines. Nevertheless, a notable deviation emerged when analyzing the treatment application period separately. Hence, it is recommended to incorporate considerations for the type and timing of treatment, extending beyond the current guideline, which solely accounts for the severity by disease.

• Korean Journal of Materials Research
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• v.24 no.11
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• pp.610-616
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• 2014

In this study, we investigated the precipitation behavior of the R-phase precipitated at the initial stage of aging and its effect on the pitting corrosion of 25%Cr-7%Ni-4%Mo super duplex stainless steel. The R-phase in super duplex stainless steel was mainly precipitated at the interface of ferrite/austenite phases and inside of the ferrite phase during the initial stage of aging, and it was transformed into the ${\sigma}$-phase with an increase in aging time. The ferrite phase was decomposed into a new austenite phase and ${\sigma}$-phase. The R phase was an intermetallic compound, which represented a lower Ni and higher Mo than the matrix, and also had a higher Mo and Cr concentration than the ${\sigma}$ phase. With an increasing aging time, the pitting potential $E_p$ was increased slowly by the precipitation of the R-phase, and it was then steeply decreased by the precipitation of the ${\sigma}$-phase. The R-phase was decreased the pitting potential, but its effect was smaller than effect of ${\sigma}$-phase.

• 대한방사선치료학회:학술대회논문집
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• 2005.06a
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• pp.13-17
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• 2005

Introduction : For stereotactic radiosurgery (SRS) of a tumor in the region whose movement due to respiration is significant, like Lung lower lobe, the gated therapy, which delivers radiation dose to the selected respiratory phases when tumor motion is small, was peformed using the Respiratory gating system and its clinical effectiveness was evaluated. Methode and Materials : For two SRS patients with a tumor in Lung lower lobe, a marker block (infrared reflector) was attached on the abdomen. While patient' respiratory cycle was monitored with Real-time Position Management (RPM, Varian, USA), 4D CT was performed (10 phases per a cycle). Phases in which tumor motion did not change rapidly were decided as treatment phases. The treatment volume was contoured on the CT images for selected treatment phases using maximum intensity projection (MIP) method. In order to verify setup reproducibility and positional variation, 4D CT was repeated. Result : Gross tumor volume (GTV) showed maximum movement in superior-inferior direction. For patient $\#$1, motion of GTV was reduced to 2.6 mm in treatment phases ($30\%\~60\%$), while that was 9.4 mm in full phases ($0\%\~90\%$) and for patient $\#$2, it was reduced to 2.3 mm in treatment phases ($30\%\~70\%$), while it was 11.7 mm in full phases ($0\%\~90\%$). When comparing two sets of CT images, setup errors in all the directions were within 3 mm. Conclusion : Since tumor motion was reduced less than 5 mm, the Respiratory gating system for SRS of Lung lower lobe is useful.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1014-1017
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• 2003

열증착법을 이용하여 copper(II) phthalocyane (CuPc)의 박막을 제작하였다. 기판의 예열 온도를 달리하여 제작된 CuPc의 박막은 ${\alpha}-phase$와 ${\beta}-phase$로 구분할 수 있으며 phase에 따른 결정 구조를 관찰하기 위해 x-ray diffraction을 사용하고 peak의 위치를 관찰하였다. 또한 SEM, UV visible absorption spectra의 변화를 통해 온도에 따라 상전이가 이행해 가는 모습을 구체적으로 관측하였다. 이러한 결정 구조의 변화는 CuPc 박막의 전기전도 특성에 영향을 달리하여 유기발광 소자에 응용이 가능할 것으로 예상된다.

• Environmental Mutagens and Carcinogens
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• v.24 no.3
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• pp.128-136
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• 2004

CYP1A1 is known to be inducible by xenobiotic compouds such as polyciclic aromatic hydrocarbons(PAHs) and 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). These chemicals have been identified worldwide and can have a significant impact on the human health and well being of human and wildlife. Given these issues, the detection and quantification of these chemicals in biological, environmental and food samples is important. First, we investigated the effect of on CYP1A1 promoter activity, 7-ethoxyresorufin-O-deethylase(EROD) activity and CYP1A1 mRNA expression induced by benzo(k)fluoranthene(B(k)F) in MCF-7 cells. We found that B(k)F significantly up-regulates the level of CYP1A1 prompter activity, EROD and CYP1A1 mRNA. When cells were treated with genistein, it was not changed that EROD and CYP1A1 mRNA, compared to that of control. However, genistein inhibited the B(k)F-induced CYP1A1 promoter activity and mRNA level at high concentration. Furthermore, in this study, effects of HDAC(histone deacetvlase) inhibitors on human prostate cancer cells proliferation were examined. HC-toxin, SAHA and TSA inhibited cell proliferation in PC3 cells. A novel HDAC inhibitor, IN2001 also suppressed the growth of PC3 cells. And IN2001 and SAHA increased S phase and G2/M phase at 12 hrs treatment but cells were arrested G0/G1 phase at 45 hrs treatment. The HC-toxin treatment for 24 hrs and 48 hrs increased G0/G1 at low concentration ($0.1\mu\textrm{m}$) but increased G2/M at more than concentration of $1\mu\textrm{m}$. TSA increased G2/M phase. These findings height the possbility of developing HDAC inhibitors as potential anticancer therapeutic agents for the treatment of prostate cancer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2803-2809
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• 2009

For a successful construction project not only construction engineering and project management technology but also economic evaluation technique is required. Design and construction technologies are necessary to receive a project order. However, construction management technology which can be apply from the project initial phase to the project operation and management phase is required to create a benefit from the project. Construction management technology is one of the effective factors for project success. Economical and efficient cost management from the planning phase influences the project success. This study investigated cost flow and cost factors of domestic Sewage Treatment Plant project for systematic analysis of cost items following the entire project phase. Particularly, data modeling based on domestic Sewage Treatment Equipment maintenance cost DB was performed, and maintenance cost estimation trend line is suggested using Monte carlo Simulation Method to decrease uncertainty of actual results DB and for feasibility study. Korea Academia-Industrial cooperation Society. The Korea Academia-Industrial cooperation Society. The Korea Academia-Industrial cooperation Society. The Korea Academia-Industrial cooperation Society.