• Clean Technology
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• v.29 no.1
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• pp.39-45
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• 2023

To investigate the effects of Mg addition at different aging times and temperatures, Cu/MgO/Al₂O₃ catalysts were synthesized for the low-temperature water gas shift (LT-WGS) reaction. The co-precipitation method was employed to prepare the catalysts with a fixed Cu amount of 30 mol% and varied amounts of Mg/Al. Synthesized catalysts were characterized using XRD, BET, and H₂-TPR analysis. Among the prepared catalysts, the highest CO conversion was achieved by the Cu/MgO/Al₂O₃ catalyst (30/40/30 mol%) with a 60 ℃ aging temperature and a 24 h aging time under a CO₂-rich feed gas. Due to it having the lowest reduction temperature and a good dispersion of CuO, the catalyst exhibited around 65% CO conversion with a gas hourly space velocity (GHSV) of 14,089 h-1 at 300 ℃. However, it has been noted that aging temperatures greater or less than 60 ℃ and aging times longer than 24 h had an adverse impact, resulting in a lower surface area and a higher reduction temperature bulk-CuO phase, leading to lower catalytic activity. The main findings of this study confirmed that one of the main factors determining catalytic activity is the ease of reducibility in the absence of bulk-like CuO species. Finally, the long-term test revealed that the catalytic activity and stability remained constant under a high concentration of CO₂ in the feed gas for 19 h with an average CO conversion of 61.83%.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.404-408
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• 2007

In this study, we investigated the effects by age of long-tenn supplementation of Epimedium koreanum Nakai (EKN)-containing water on the in vivo antioxidant capacities of rats. All rats were reared in a conventional system, and none of the rats showed any signs of aversion to the EKN solution. Neither the mean nor maximum life spans of the rats were extended by long-tenn administration of the solution. The EKN extract caused decreases in the levels of serum thiobarbituric acid reactive substances in the rats. The activities of superoxide dismutase, catalase, and glutathione (GSH) peroxidase within the liver cytosol decreased with age in both the control and EKN-supplemented groups. GSH peroxidase activity, however, was higher at old age in the EKN-supplemented group. The activities of GSH reductase and GSH-S-transferase, and the levels of free-sulfhydryl (SH) and total-SH group gradually decreased with age in both groups. However, there was some tendency for higher levels in the EKN supplemented group at a corresponding age. These results indicate that long-tenn supplementation of EKN water extracts alone does not exhibit discernible adverse effects in rats, and has some enhancing effects on the antioxidant capacities of the blood and liver, but it does not have life-prolonging effects.

• Communications for Statistical Applications and Methods
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• v.17 no.3
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• pp.423-440
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• 2010

The purpose of this paper is to prepare the department creation and the staff increase of education institution by forecasting the demand of health and welfare workers according to execution of the elderly's long-terms treatment insurance system in July, 2008. We estimated confirmors of the elderly's long-terms treatment and the demand of professional workers of health and welfare field due to the increase of care insurance users in facilities treatment organization, care at home service facilities, and family allowance facilities for 2010-2030. The numbers of social welfare professional worker are estimated as 16,624 workers in 2020 and 24,688 workers in 2030. The numbers of nurses are forecasted as 11.287 in 2020 and 16,624 in 2030, we expect that the increase of the demand be accelerated. The demand of necessary care probation worker is 44,824 in 2009, but we already trained over around 500,000 workers in 1,078 education institutions through one year in Aug. 31, 2009, which excesses over the numbers of workers demanded as much as 10 times.

• Journal of agricultural medicine and community health
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• v.12 no.1
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• pp.102-110
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• 1987

One of the familiar medical facility that most people reach easily in Korea is the drug store. In Korea, it is possible to purchase all kinds of common drugs without physician's prescriptions, which caused some problems. In other words, such treatment without professional supervision has led to medical, social and economical problems. In view of the above, this study is aimed at revealing the actual status of long-term use of drugs in some urban residents. Long-term use of drugs is operationally defined as using certain drugs at least once a week for more than 3 months. This survey took the residents of Guro 6-Dong where was one of the target areas for Community Health Development Project managed by Korea University as a target population. A sample of 1,517 residents was selected by the multistage sampling method. The interview was conducted on September 21st and 22nd in 1985. The object of this study was to compare the result with that of the rural area which was obtained by the same method, tools and research team, prior to this study in 1984. The results were as follows; 1) The age-standardization of the study showed that 97 per 1,000 urban residents were actually on long-term drug use. The prevalance of long-term use is high in accordance with aging and low with education level. 2) Out of 1,000 urban samples the most popular item involved in the long-term drug use was antipyretic-analgesic-antiinflammatory drug (26), and next in order was vitamin (23), antibiotics (13), digestives (10) and antacids (7). In the rural samples as for compare, that was antipyretic-analgesic-antiinflammatory drug (100), antacids (36), digestives (23), adrenocortical hormones (12) etc. 3) With antipyrctic-analgesic-antiinflammatory drugs, 50% of the urban samples were taking for more than a year, whereas such were 82.7% of the rural samples. Using such a high percentage of antipyretic-analgesic-antiinflamatory drugs in the rural residents is probably due to the high prevalence rate of musculo-skeletal diseases. 4) The urban long-term drug users of antipyretic-analgesic-antiinflammatory drugs were influenced mostly by the mass media (43.6%), next in order was pharmacist (35.9%) and physician (10.3%). Comparing with the result from the rural areas the role of mass media was much more influencial in the urban areas. 60% of them consulted with pharmacists, 14.3% with physicians and 25.7% had no history of consultation in the urban samples. 5) Considering the incidence of knowing the possible side-effects of each drug, 28.2% of the urban residents had no recognition about side-effects prior to use antipyretic-analgesic-antiinflammatory drugs. In the rural residents, 29.67o had no knowledge about the side-effects before using the drug. 6) For the solution of the above problems, it is necessary to limit the advertisement of some drugs by the parmaceutical company. And therapeutic drugs which may bring on side effects in case of long-term use should not be sold at drug stores without physician's prescription.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.5
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• pp.385-392
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• 2014

The isolators have been generally used to reduce a seismic force. If the isolators apply to the nuclear power plants(NPPs), the durability and capacity for the structures and equipments should be ensured during the life time. In this study, the long-term behavior of isolated NPPs was analyzed for ensuring the seismic safety. The properties of isolator due to the age-related degradation were analyzed. And the seismic behavior of isolated buildings was analyzed by considering the aging of rubber bearings in different temperature environments. According to the analysis results, the natural frequency of structures was increased with time. But the maximum acceleration and maximum displacement of isolated structures have not changed significantly. Although the damaged of structure did not occurred by aging of isolators, it was presented that the spectral acceleration at the target frequency of isolated structure increased with the temperature. Therefore the isolators in the isolated buildings should be carefully designed and manufactured considering the temperature-dependancy of rubber material.

• Health Policy and Management
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• v.8 no.1
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• pp.232-265
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• 1998

Taiwan has experienced rapid economic growth during the past two decades. As a result, the demand for health care in Taiwan has increased rapidly. To meet the rising demand, Taiwan implemented a National Health Insurance (NHI) program on March 1, 1995. This program now covers more than 96 percent of Taiwan's citizens. Implementation of the NHI in 1995 represents fulfillment of a primary social and health policy goals of Taiwan. The goals of the NHI program is to eliminate financial barriers of health care for the citizens, to improve the quality of care. To achieve these goals, the NHI was designed on the following principles: 1. All Taiwan citizens are compul내교 joined the NHI program by law; 2. The NHI program provides comprehensive services; 3. The NHI is run by one single govt' subsidy; 5. The NHI adopt fee-for-services scheme to pay medical expenses and copayment to avoid abouse of medical services. However, the scheme did not bring in the efficient use of health care C. National Health Council, 1986 NARC, Aging in Japan, International Publication Series 1991;2 Kahana EF. Kiyak HA. Attitude and behavior of staff in facilities for the aged, 1984 Naoki I, John CC. Health polic report japan's medical care system, New England Joumal of Medicine 1995; 333(19) National Economic Research Associates, The Health CAre System in Japan, NERA, 1993. National Federation of health Insurance Societies (KEMPOREM), Health Insurance and Health Insurance Societies in Japan, 1995. Owe Ahlund, Aging and housing in sweden, Paper presented at the International Symposium, Long term Care Facility, 1993. Statisitics Jahrbuch, Statistisches Bundesamt, 1992. Stein S. Linn, MIW. and Stein EM. Patient's anticipation of stress in nursing home care, 1985. U. S. Senate Special Committee on Aging, A Report of the special Committee on Aging, Washing D. C, 1992. U.S. Bureau of the Census, 1994.

• Journal of Magnetics
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• v.15 no.4
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• pp.209-212
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• 2010

Photoplethysmogram (PPG) and pressure pulse waveform (PPW) were compared and evaluated for the efficacy of stimulating knuckles by using the pulsed magnetic field. Both signals were observed simultaneously while the knuckles were exposed for 10 min to the pulsed magnetic field, with maximum field intensity of 0.8 T and transition time of 0.126 msec. After 5 min stimulation of the knuckles, the results showed that the aging indexes calculated from the second derivative of the PPG were increased from -1.913 to 0.072, and that of the PPW from -0.063 to 0.387. However, for the relatively long-term stimulation for 10 min, we found that the values of both the aging indexes of the second derivatives and augmentation index of the PPW returned to the starting level. The changes observed in characteristic factors such as the aging indexes of the second derivatives and augmentation index of the PPW indicate the potential of pulsed magnetic field stimulation as a therapeutic method for the treatment of patients with peripheral vascular disease.

• Nuclear Engineering and Technology
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• v.47 no.6
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• pp.712-718
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• 2015

Cast duplex stainless steels are susceptible to thermal aging during long-term service at temperatures ranging from $280^{\circ}C$ to $450^{\circ}C$. To analyze the effect of thermal aging on leak-before-break (LBB) behavior, three-dimensional finite element analysis models were built for circumferentially cracked pipes. Based on the elasticeplastic fracture mechanics theory, the detectable leakage crack length calculation and J-integral stability assessment diagram approach were carried out under different bending moments. The LBB curves and LBB assessment diagrams for unaged and thermally aged pipes were constructed. The results show that the detectable leakage crack length for thermally aged pipes increases with increasing bending moments, whereas the critical crack length decreases. The ligament instability line and critical crack length line for thermally aged pipes move downward and to the left, respectively, and unsafe LBB assessment results will be produced if thermal aging is not considered. If the applied bending moment is increased, the degree of safety decreases in the LBB assessment.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.149-154
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• 2011

In order to explore properties of various rubber compounds after thermal aging under the condition similar to the operating environment of a fuel cell-stack, heat resistance and compression set of those compounds were investigated for a long term operation in $H_2SO_4$, $H_2O$, and LLC (ethylene glycol : $H_2O=50:50$) solution. It was assumed that aging Acrylonitrile butadiene rubber (NBR) and Elthylene Propylene diene rubber (EDPM) compound in the solution resulted in discoloration as time passed. It was also found that hydrolysis was developed on the Silicone rubber (VMQ) compound intentionally aged under acidic condition by means of TGA, SEM, and EDS analysis.

• Journal of Digital Convergence
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• v.13 no.12
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• pp.41-46
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• 2015

In spite of increasing women migrants, proper social programs based on human rights are hardly found. In this paper, with the implication of 'diaspora', the essential term of multi-culturalism from the perspective of migrant women is briefly discussed. Also, social programs for migrant women are suggested through looking into the experiences of EU. EU policies and social programs are reorganized through data analysis and policy contents analysis. EU has longer history of immigration, and has provided the proper and long-term programs to accept migrant women as the qualified social member. EU social programs are based on the principles of non-discrimination, full employment, human rights and citizenship. Social programs should imply long-term inclusive policy for migrants, and help migrants to experience empowerment in the society. By looking into some examples of social programs of employment, education and general knowledge, useful social programs are to be suggested.