• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.3
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• pp.247-260
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• 2010

The developement of a HLW disposal canister is under way in KAERI using Cold Spray Coating technique. To estimate corrosion behavior of a cold sprayed copper, a creivice corrosion test was conducted at Southwest Research Institute(SWRI) in the United State. For the measurement of repassivation potential needed for crevice corrosion, three methods such as (1) ASTM G61-86 : Cyclic Potentiodynamic Polarization Measurements, (2) Potentiodynamic Polarization plus intermediate Potentiostatic Hold method, and (3) ASTM G192-08 (THE method) : Potentiodynamic- Galvanostatic-Potentiostatic Method, were introduced in this report. In the crevice corrosion test, the occurrence of corrosion at crevice area was optically determined and the repassivation potentials were checked for three kind of copper specimens in a simulated KURT underground water, using a crevice former dictated in ASTM G61-86. The applied electrochemical test techniques were cyclic polarization, potentiostatic polarization, and electrochemical impedance spectroscopy. As a result of crevice corrosion tests, every copper specimens including cold sprayed one did not show any corrosion figure on crevice areas. And the open-cell voltage, at which corrosion reaction initiates, was influenced by the purity of copper, but not their manufacturing method in this experiment. Therefore, it was convinced that there is no crevice corrosion for the cold sprayed copper in KURT underground environment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05a
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• pp.131-134
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• 2005

PDP 방전 셀의 최적화 및 진공자외선 발광효율을 향상시키기 위한 목적으로 AC - PDP 미소방전에서 제논 여기종 원자의 밀도를 측정하는 레이저 흡수법을 개발하였다. 본 연구에서는 PDP 셀의 기체 압력을 350Torr, 제논 함량 10%로 고정하고, 전극 위에서의 여러 위치에서 준안정 준위 제논의 밀도를 흡수법으로 측정하였다. 실험 결과 제논 여기종의 밀도의 최대값은 전극의 위치(가장자리에서 안쪽으로의 거리)가 $50{\mu}m$, $120{\mu},\;150{\mu}m$ 일 때 $3.5{\times}10^{12}cm^{-3}$, $2.8{\times}10^{12}cm^{-3}$, $2.2{\times}10^{12}cm^{-3}$로 나타났다.

• Korean Journal of Acupuncture
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• v.30 no.2
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• pp.135-142
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• 2013

Objectives : This study aimed to investigate the general effects of low-frequency electrical stimulation of the ankle joint acupuncture points(BL62 and KI6) on the brain waves of elderly women as a pilot study to figure out the possibility of candidate non-invasive and non-chemical stimulation method for the enhancing the brain function. Methods : A randomized, controlled, double-blinded clinical trial was performed in 31 healthy women(mean age, 54.5 years) within a treatment duration of 12 sessions. In the experimental group, low-frequency electrical stimulation was applied using the maximum range of the individual insensible strength(mean current, $0.04{\mu}A$). The control group received sham stimulation. The background electroencephalographic activity was measured before and after the12 sessions. Results : After 12 sessions of stimulation, the relative power of the alpha wave increased(32 of 32 channels: significant difference in 11 channels, p<0.05); the theta(30 of 32 channels: significant difference in 10 channels, p<0.05), beta(31 of 32 channels), and gamma(30 of 32 channels: significant difference in 7 channels, p<0.05) powers were also decreased compared with the sham group. Conclusions : Electrical stimulation on the ankle joint acupuncture points(BL62 and KI6) seemed to stabilize the elderly women brain by inducing the alpha power and reducing beta, theta, and gamma powers. These results provide insight into the action mechanism of the stimulation and can assist the future developement of a non-invasive and non-chemical treatment technique for stressor related cognitive problems.

• Journal of IKEEE
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• v.22 no.4
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• pp.1214-1217
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• 2018

In this paper, we propose the development of a Small $360^{\circ}$ Oral Scanner embedded board. The proposed small $360^{\circ}$ oral scanner embedded board consists of image level and transfer method changing part FPGA part, memory part and FIFO to USB transfer part. The image level and transmission mode change unit divides the MIPI format oral image received through the small $360^{\circ}$ oral cavity image sensor and the image sensor into low power signal mode and high speed signal mode and distributes them to the port and transfers the level shift to the FPGA unit. The FPGA unit performs functions such as $360^{\circ}$ image distortion correction, image correction, image processing, and image compression. In the FIFO to USB transfer section, the RAW data transferred through the FIFO in the FPGA is transferred to the PC using USB 3.0, USB 3.1, etc. using the transceiver chip. In order to evaluate the efficiency of the proposed small $360^{\circ}$ oral scanner embedded board, it has been tested by an authorized testing institute. As a result, the frame rate per second is over 60 fps and the data transfer rate is 4.99 Gb/second

• 한국사회정책
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• v.23 no.3
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• pp.49-77
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• 2016

The aim of this study is to reveal errors in the estimations on the nonstandard workers scale which have resulted from little consideration for bogus self-employment. Bogus self-employment means disguised employment relationships that are considered to be self-employed workers even though they have inherent subordination. The methods of previous studies estimate that the bogus self-employed workers are excluded from estimations because they are not workers in principle. We analyze the scale of the bogus self-employments using the empirical data [the Korean Welfare Panel of 2008-2013(six wave panel)] to re-estimate the scale of non-standard workers. In 2013, the year of the last wave, the percentage of the bogus self-employment was high, the proportion of them is 28.5% among self-employment without owning a place of business. Our results expect the number of contract workers from re-analysis would be over 740 thousand when reflecting on the predictive value in the actual number of paid workers. In conclusion, it is necessary to apply reasonable methods of analysis concerning the scope and scale of the nonstandard workers for the sake of coping with measures against the problem of nonstandard workers. The aim of this study is to reveal the estimation error on nonstandard workers' scale which are resulted from having no consideration for bogus self-employment. Bogus self-employment means disguised employment relationship that is considered as self-employment workers even though they have inherent subordination. The methods of previous researches' estimation on nonstandard workers have the problem that the bogus self-employment workers are excluded from estimation because they are not workers in principle.

• Journal of Korean Society of Disaster and Security
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• v.15 no.3
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• pp.57-66
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• 2022

According to the official letter of the Ministry of Employment and Labor (recent guidance on the status of deaths in the construction industry and thorough safety management, April 4, 2022), 17 deaths occurred in construction works worth more than 5 billion won until March 31, 2022. In terms of the size of the construction, 7 cases of 5 billion won to 12 billion won, 5 cases of 12 billion won to 80 billion won, and 5 cases of more than 80 billion won occurred. The causes of death accidents were found to be nine cases (50%), five cases (28%), two cases of collapse (11%), one case of entrapment (5%), and one case of drowning (5%). Safety facilities need to be strengthened to reduce deaths caused by falling, which accounts for most of the deaths, and if fall prevention nets, openings, and safety rails are completely installed, most falling accidents can be prevented. Therefore, this paper intends to present cases of development and use of patent technology through improvement of safety facilities in order to prevent accidents corresponding to the fall of new urban living housing sites, which are small apartment houses.

• Convergence Security Journal
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• v.24 no.2
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• pp.89-104
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• 2024

This study is an empirical study to examine the factors that influence the intention to use artificial intelligence (AI) technology for SW engineering-related tasks, and the purpose of the study is to understand the key factors that influence the use in terms of AI augmentation characteristics and interactive UI/UX characteristics. For this purpose, a survey was conducted among information and communication workers who have experience in using AI-related technologies and the collected data was analyzed. The results of the empirical analysis showed that perceived usefulness was positively influenced by the factors of expertise, interestingness, realism, aesthetics, efficiency, and flexibility, and perceived ease of use was positively influenced by the factors of expertise, interestingness, realism, aesthetics, and flexibility. Variety had no effect on both perceived ease of use and perceived usefulness. Perceived ease of use had a significant effect on perceived immersion, which positively influenced intention to use. These findings are significant in that they provide an academic understanding of the factors that influence the use of AI-enhanced tools in SW engineering-related tasks such as application design, development, testing, and process automation, as well as practical directions for the creators of tools that provide AI-enhanced development services to develop user acquisition strategies.

• Journal of Chest Surgery
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• v.37 no.9
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• pp.762-767
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• 2004

With the developement of non-invasive surgical techeniques, coronary artery bypass graft without cardiopulmonary bypass has become popular. We compared the preoperative risk factors and in-hospital outcomes of patients having off-pump CABG with these having on-pump CABG. Material and Method： From January 2001 to June 2003, 87 patients underwent CABG. Thirty-sin patients underwent on-pump CABG, fifty-one patients under-went off-pump CABG. Preoperative risk factors, extent of coronary disease, operative time, postoperative endotracheal intubation time, duration of ICU stay & hospital stay, the amount of bleeding and postoperative levels of cardiac enzymes were compared in both groups, Result: The were no differences in their sex ratios, ages, preoperative risk factors, preoperative Ml, Canadian classes, extent of coronary artery diseases and, echocardio-graphic ejection fraction between Off-pump CABG and On-pump CABG groups. Off-pump CABG group had significantly lower mean operative time (270$\pm$79.3 min vs 372$\pm$142.2 min, p＜0.001), mean ventilation time (17.1$\pm$13.4 hr vs 24.3$\pm$17.8 hr) and CK-MB level (8,9$\pm$18.7 IU/L vs 25.7$\pm$8.4 IU/L) than on-pump CABG groups, On-pump CABG group had more distal grafts (2.2$\pm$0.5 vs 1.7$\pm$0.71 than Off-pump CABG groups did. There were no differences in their postoperative complications and outcomes including amount of postoperative bleeding for 24 hrs, reoperation for bleeding control, mean in-hospital days, postoperative infection, renal failure and neurologic complications between Off-pump CABG and On-pump CABG groups. Conclusion: This study showed that patients who underwent Off-pump CABG had less operation time & intubation time and lower CK-MB level; however, they also have less distal graft. Even though CABG without CPB provided satisfactory results, more clinical experience & longer follow-up is required.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.4
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• pp.285-294
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• 2000

In order to determine the horizontal and vertical distributions of metals and prospect the recent metal pollution history in Nakdong Estuary, we took surface and core sediments. Maximum value of organic matter occurs at the upstream site located 4 km from Nakdong barrage, and the concentration of trace metals (Zn, Cu, and Pb etc.) decrease seaward in the estuary. The sedimentation rates, based on $^{210}$Pb$_{ex}$ and $^{137}$Cs activities, were 0.34 cm/yr in inside of barrage (core 1) and 0.25 cm/yr in Changrim (core 4). Sediment mixing layer does not exist in core 1, where anoxic condition is known to be prevail. The topmost sediment layer of core 4 (<3.5 cm) is severely mixed. At sites 1 and 4, concentrations of Cu slowly increased during the period of 1920-1970, rapidly increased during 1970-1990, and followed by slight decrease after 1990. Zn contents increased in early 1960s and peaked in 1993, and followed by decrease after 1990s. Pb has increased continuously since early 1970s. At the downstream of the barrage, Cu and Zn have increased in the topmost layer. The trend of increase of Cu is evident after 1950 (11 cm in sediment depth). Overall trend of heavy metal concentration clearly indicates the pollution has been increasing after the construction of the barrage.

• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.169-174
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• 2005

This study was comducted to examine the effects of culture medium, and the osmolarity and osmotic change of the culture medium on in vitro maturation of porcine oocytes and developement of porcine parthenogenetic embryos. In Experiment 1, cumulus-oocyte complexes were matured in NCSU-23, mWM and mKRB, respectively, There was no difference in maturation rate($62.1\~71.3\%$) among groups. In Experiment 2, matured oocytes in each medium were activated and cultured for 6 days in the same media. Blastocyst formation rate was higher in NCSU-23($22.9\%$) than those of others($0\~0.6\%$, P<0.05). In Experiment 3, parthenogenetic embryos were cultured for 6 days in NCSU-23 with different osmolarity(300, 280 and 256 mOsmols) adjusted by NaCl. There were no differences in development rates to the blastocyst stage($11.0\~14.4\%$) among groups. In Experiment 4, activated oocytes were cultured for 2 days in NCSU-23 with 300, 280 and 256 mOsmols and then transferred to increased or decreased osmotic condition. Blastocyst formation rate was higher in a group which was transferred from the higher osmotic condition to the lowe. osmotic condition($21.0\%$) than a contrary group( $11.8\%$, (P<0.05). This result shows that the culture medium and the osmolarity of the culture medium affect the development of porcine parthenogenetic embryos, and the change of osmolarity from the higher condition to the lower condition at a certain developmental stage can enhance the development of porcine parthenogenetic embryos.