• Journal of Information Display
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• v.9 no.4
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• pp.15-20
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• 2008

A DC-magnetron inline sputter was established, and the influence of the base pressure on the structural characteristics of the ITO thin films was studied. When the inline sputter system was established and operated for ITO sputtering, its initial vacuum level did not go below $5\times10^{-6}$ torr. The vacuum leak test was conducted by measuring t he elapsed time until the vacuum level reached $1\times10^{-6}$ torr. The base pressure was successfully maintained at $1\times10^{-6}$ torr for 900 min, and the uniformity of the ITO film that had been deposited at this pressure significantly improved.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.19-35
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• 2003

In order 새 investigate the spatial and seasonal variations of heavy metal pollution in heavily industrialized urban area, urban roadside sediments were collected for five years from gully pots in Seoul City. A series of studies have been carried out concerning the physicochemical characteristics of the sediments in order to evaluate the contamination of heavy metals such as Cd, Co, Cr, Cu, Ni, Pb and Zn. Roadside sediments and uncontaminated stream sediments were analyzed for total metal concentrations using acid extraction. The roadside sediments are characterized by very high concentrations of Zn (2,665.0$\pm$1,815.0 $\mu\textrm{g}$/g), Cu (445.6$\pm$708.0 $\mu\textrm{g}$/g), Pb (214.3$\pm$147.9 $\mu\textrm{g}$/g) and Cr (182.1$\pm$268.8 $\mu\textrm{g}$/g), indicating an artificial accumulation of these metals to the sediment chemistry. Comparing with average contents of uncontaminated stream sediments, roadside sediments were shown zinc 14 times (up to 64.4), copper 9 times (up to 181.7), lead 6 times (up to 63.7), cobalt 6 times (up to 168.7), nickel 4 times (up to 98.4), cadmium 2 times (up to 12.8) and chrome 2 times (up to 40.2) high content. The relative degree of heavy metal pollution for roadside sediments collected from each district in Seoul City is evaluated using the “geoaccumulation index”. As a result, heavy-metal contamination is highest centering the oldest residential district and industry area, and contamination level decreases as go to outer block of the city. The factor analysis results indicate that the levels of Cu, Ni, Fe and Cr are strongly related to numbers of factories, whereas the concentrations of Cr, Zn and Cd dependant on pollution index, indicating artificial contamination due to site-specific traffic density.

• Journal of Society of Preventive Korean Medicine
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• v.15 no.1
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• pp.17-27
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• 2011

Objective : The purpose of this study was to identify the trend of research in the Korean Journal of Oriental Preventive Medicine and to suggest future perspective for oriental preventive medicine research. Method : The contents of 344 articles published in this journal was reviewed from its beginning year 1997 to year 2010. Result : The number of articles was increased as times go on. An analysis of the research design showed, experimental research (in vivo or in vitro) was 36.9%, survey research was 26.5%, review was 20.1%. In the major classifications of topics published, health management 28.5%, oriental medicine effectiveness 25.3%, herbal safety and toxicity 13.1%, and environmental and occupational medicine 9.0% respectively. Conclusion : There has been a lack of health preservation(Yang-saeng) topic, epidemiology and health statistics topic. Further research need qualitative study and each subjects of oriental preventive medicine.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.1
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• pp.83-91
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• 2014

PURPOSE: The purpose of this study was to investigate the effects of task oriented circuit exercise(TOCE) on the balance and cognition in mild dementia patients. METHODS: The subjects of the study were 30 patients with mild dementia and assigned to the TOCE(task oriented circuit exercise) group(n=15) and aerobic exercise(AE) group(n=15). TOCE group performed six task three times weekly for 12 weeks. AE group underwent the cycle ergometer and treadmill exercise three times a week during the experimental period respectively. Timed up and go test(TUG), Berg balance scale(BBS) and AP1153 Biorescue were used to assess the parameters for the balance. Korean-mini mental state examination and Global deterioration scale(GDS) were used to assess the parameters for the cognition. For the statistical analysis, paired t-test and independent t-test were used to compare the differences among two groups. RESULTS: Each group showed improvement in balance and possibility for improving cognitive function. TOCE group especially, there were significant improvements in limit of stability. CONCLUSION: The results of the study suggest that TOCE is a more diverse exercise programs introduced in the study. Furthermore, TOCE can be a helpful to improve the balance and cognition in mild dementia patients.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.3
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• pp.325-331
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• 2014

PURPOSE: Improving elderly people's balance ability through pilates which may be easily applied in ordinary life is considered an important intervention method for elderly people. Therefore, this study examines the effects of pilates training on elderly people's static and dynamic balance abilities and provides clinical data to improve this ability. METHODS: The pilates program was applied to 19 elderly subjects three times per week for 8 weeks. Their training level took into consideration their age and was set so that the rating scales of perceived exertion became 13 to 14. Prior to the initiation of the experiment, the subjects had an adaptation period in order to practice the order and motions of pilates. After the adaptation period, the subjects received training. The program was conducted three times per week, for eight weeks. Their dynamic balance ability was observed through the timed up and go (TUG) test and tandem walk test (TWT), and their static balance ability was evaluated by the center of pressure (COP) area, medial-lateral displacement, and anterior-posterior displacement. RESULTS: The results of the TUG test and TWT and evaluations of the COP area and medial-lateral displacement were significantly different after the pilates exercise program compared to those before the program began. CONCLUSION: The results show that an 8-week pilates exercise program is an effective method to increase elderly people's static and dynamic balance abilities. In addition, the application result of the pilates exercise program will provide useful information for future research on elderly people's balance ability.

• Korean Journal of Materials Research
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• v.1 no.1
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• pp.17-22
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• 1991

Tantalum thin films were deposited by DC sputtering on heavily doped single Si substrates. These substrates were treated by means of a rapid thermal annealing (RTA) under Ar atmosphere for various temperatures($600-1100^{\circ}C$). The silicide formation and the impurities behavior in the substrate are studied by means of XRD, SEM, four-point probe, HP4145, and SIMS. The formation of $TaSi_2$ started at $800^{\circ}C$ for all kinds of impurities and the entire Tantalum thin metal films were transformed into $TaSi_2$ above $1000^{\circ}C$ Also the contact resistance for $TaSi_2/P^+$ region had a low value; $22{\Omega}$, at contact site of $0.9{\times}0.9(\mu\textrm{m^2}$), and implanted impurities were diffused out into the $TaSi_2$ for rapid thermal annealing.

• Journal of IKEEE
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• v.23 no.2
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• pp.425-430
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• 2019

This work describes the design and characterization of a X-band power amplifier (PA) monolithic microwave integrated circuit (MMIC) using a $0.25{\mu}m$ gate length gallium nitride (GaN) high electron mobility transistor (HEMT) technology. The developed X-band power amplifier MMIC has small signal gain of over 22.7 dB and saturated output power of 43.02 dBm (20.04 W) over the entire band of 9 to 10 GHz. Maximum saturated output power is a 43.84 dBm (24.21 W) at 9.5 GHz. Its power added efficiency (PAE) is 41.0~51.24% and the chip dimensions are $3.7mm{\times}2.3mm$, generating the output power density of $2.84W/mm^2$. The developed GaN power amplifier MMIC is expected to be applied in a variety of X-band radar applications.

• Journal of International Academy of Physical Therapy Research
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• v.10 no.4
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• pp.1926-1933
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• 2019

Background: Physical therapy has been widely studied in various fields, however, the academic trends and characteristics has not been systematically analyzed. Semantic network analysis is used as an approach for this study. Objective: To explore academic trends and knowledge system in the physiotherapy research in the Journal of International Academy Physical Therapy (J of IAPTR) Study design : Literature review Method: Semantic network analysis was conducted using the titles of 272 articles published in the Journal of IAPTR from 2010 to 2019. Results: Frequency analysis revealed following most frequently used key words; Stroke (27 times), Balance (21 times), Elder (13 times), Forward head posture (FHP, 11 times), Muscle activity (9 times). The relationship between the presented keywords is divided into six subgroups (FHP and pain, walk and quality, elder and balance, stroke and apoptosis, muscle strength and function) according to their correlation and frequency to be used together. Conclusion: The study is considered to be of help to researchers who want to identify research trends in physiotherapy.

• Korean Journal of Materials Research
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• v.9 no.4
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• pp.345-348
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• 1999

The properties of Fe ions in the $ CdFe_2$$O_4$ and $CdFeAlO_4$ were investigated using the Mossbauer spectroscopy, in the temperature range from 300K to 900K. The calculated Debye temperature, recoil free fraction, mean square displacement and velocity are, 476.5K, 0.835, 3.39$\times$10\ulcorner$\textrm{cm}^2$, and 1.11$\times$10\ulcorner$\textrm{cm}^2$sec$^2$for Fe ions in the $CdFe_2$$O_4$ and 369.0K, 0.741, 5.65$\times$10\ulcorner$\textrm{cm}^2$ and 1.33$\times$10\ulcorner$\textrm{cm}^2$/$sec^2$in the $CeFeAlO_4$. The difference of the properties in the two samples were explained by the variation of the Fe\ulcorner-O\ulcorner bonding length with the substituted Al ions.

• Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.17.1-17.9
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• 2016

The seasonal variation of fecal coliforms (FCs) and physicochemical factors was determined in seawaters of the Hansan-Geojeman area, including a designated area for oyster, and in inland pollution sources of its drainage basin. The mean daily loads of FCs in inland pollution sources ranged from $1.2{\times}10^9$ to $3.1{\times}10^{11}$ most probable number (MPN)/day; however, the pollutants could not be reached at the designated area. FC concentrations of seawaters were closely related to season, rainfall, and inland contaminants, however, within the regulation limit of various countries for shellfish. The highest concentrations for chemical oxygen demand (COD) and $chlorophyll-{\alpha}$ in seawaters were shown in the surface layer during August with high rainfall, whereas the lowest for dissolved oxygen (DO) in the bottom layer of the same month. Therefore, it indicates that the concentrations of FC, COD, DO, and $chlorophyll-{\alpha}$ of seawaters were closely related to season and rainfall.