• Korean Journal of Materials Research
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• v.11 no.3
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• pp.227-235
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• 2001

In this work, Zn$_2$SiO$_4$:Mn phosphors were prepared by solid state reaction. The effect of sintering/reduction temperature, flow rate of H$_2$-5%/$N_2$-95% mix gas, and ball milling conditions have been investigated on the sake of PDP(Plasma Display Panel) application. The characteristics such as particle morphology and photoluminescence of prepared phosphors were compared to those of commercial Zn$_2$SiO$_4$:Mn Phosphors. It was found that the Phosphor synthesized at 130$0^{\circ}C$ with 0.08 Mn concentration had a maximum brightness, This brightness was increased more 20% by reduction treatment under 100me/min flow rate of 5%H$_2$-95%$N_2$ mixed gas. The size of particles decreased under 3$\mu\textrm{m}$ after ball milling. Especially, higher luminescence was obtained in our Zn$_2$SiO$_4$:Mn phosphors than commercial Zn$_2$SiO$_4$:Mn phosphors, so that they are able to be applied for PDP.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.423-440
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• 2000

This research was conducted to identify the following: the home care needs of patients with dementia and the burden on the primary family care giver: to provide basic data required to develop nursing intervention for the care giver: and to suggest recommendations for medical institutions and social services that could reduce the burden on the families of people suffering from dementia. subjects of this research were 53 patients of the two Public Health Centers of Cheju Province who are suffering from dementia and their families. The instrument used in the research was Kuen. Jung Don (1994)' s assessment tool of burden in the primary family care giver who has parents with senile dementia and Yoo. Young Mi(1998)'s assessment tool of home care need. modified by the researcher in the questionnaire by a Likert rating scale. The period of data collection was from February 8. 2000 to March 10. 2000. Collected data was analyzed by SPSS, using mean, standard deviation. ANOVA, t-test and Pearson correlation coefficient. The result of this research was that there was not a significant correlation between the burden on the care giver and the level of dementia, its duration, the patient's ability to perform daily tasks, the period of care giving. and the use of social services, although the lower the patient's ability to perform daily tasks. and the worse the care giver's own health situation, the higher the burden on the primary family care giver. The following suggestions are made based on the results of this research. 1. More than half of the subjects don't use social facilities and services. More publicity and referral efforts are needed about medical institutions. nursing institutions and other facilities that specialize in services for dementia sufferers and their families. 2. Nursing services should include intensive education for the primary care giver in the most important aspects of home care. 3. Further research should be done, and should include data from all parts of Cheju Province.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5C
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• pp.355-364
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• 2012

Target processing mechanisms are necessary to collect target information, real-time data fusion, and tactical environment recognition for cooperative engagement ability. Among these mechanisms, the target tracking starts from predicting state of speed, acceleration, and location by using sensors' measurements. However, it can be a problem to give the reliability because the measurements have a certain uncertainty. Thus, a technique which uses multiple sensors is needed to detect the target and increase the reliability. Also, data fusion technique is necessary to process the data which is provided from heterogeneous sensors for target tracking. In this paper, a target tracking algorithm is proposed based on probabilistic data association(PDA) by fusing radar and ESM sensor measurements. The radar sensor's azimuth and range measurements and the ESM sensor's bearing-only measurement are associated by the measurement fusion method. After gating associated measurements, state estimation of the target is performed by PDA filter. The simulation results show that the proposed algorithm provides improved estimation under linear and circular target motions.

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.638-644
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• 2010

This study was carried out to establish the informations on the optimum container for production of Larix leptolepsis container seedlings. Height growth of 1-year-old container seedling was highest in 250 mL of container (19.3 cm), and of 2-year-old seedling was in 500 mL (56.9 cm). On the other hand, the highest growth of root-collar diameter was observed in the both 1-year-old and 2-year-old seedlings grown in 500 mL. Dry mass production in both a whole seedling and each organs of 2-year-old seedling was significantly high in the container with larger volume and lower seedling density. According to the analysis using by WinRhizo program, the larger container in volume showed better root morphological traits such as total root length, root projected area, root surface area, root volume and average root diameter. Among the elements for analysis of root morphological traits, the root volume was the highest one affected by container volume. And it was observed that the root volume was 79.5% and 46.8% in 320 mL and 250 mL, respectively, compared to 500 mL.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.33-39
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• 2017

This study was carried out in order to closely examine the growth and the physiological response by shading levels of a container seedling of Daphniphyllum macropodum which is known as the species of having shade tolerance in a warm temperature evergreen broad-leaved tree. The shading treatment was regulated with the shading level of full sunlight, and 35%, 55%, 75% of full sunlight. As a result of surveying the height and the root collar diameter growth by the shading level, the height was the highest with 13.2 cm under 35% of shading. The root collar diameter was the highest with 4.99 mm under full sunlight. The organ-based (leaves, shoot and root) dry mass production and the whole dry mass production were higher with 1.38 g, 0.47 g, 0.87 g, 2.72 g, respectively, in order of 35% shading. As for chlorophyll a, b, and the total chlorophyll content, the highest chlorophyll content was shown under 75% of shading with the relatively highest shading level. The ratio of chlorophyll a to chlorophyll b (a/b) was the highest under 35% of shading. The photosynthetic rate, stomatal conductance and water use efficiency were the highest with $12.3{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$, $0.27molH_2O{\cdot}m^{-2}{\cdot}s^{-1}$, $3.53{\mu}molCO_2{\cdot}mmol^{-1}H_2O$, respectively, under 35% of shading. As a result of surveying the whole experiment, D. macropodum grows nicely by maintaining 35% shading.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.750-754
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• 2010

The purpose of this study was to investigate the antioxidant and skin whitening effects of Rhamnus yoshinoi extracts. Rhamnus yoshinoi was extracted with 100% ethanol and water. The antioxidative and skin whitening effects of extracts were determined by in vitro assays using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and inhibitory effects against tyrosinase activity and melanogenesis in B16F1 melanoma cells. The radical scavenging activities of the Rhamnus yoshinoi extracts were tested by DPPH assay and showed high DPPH radical scavenging activities (SC50; 21.6 ppm in EtOH, 40.5 ppm in water). As for tyrosinase inhibitory activity, the Rhamnus yoshinoi ethanol extract had the highest inhibition activity ($IC_{50}$; 256.3 ppm). In B16F1 mouse melanoma cells, the Rhamnus yoshinoi ethanol extract significantly inhibited melanin synthesis by 53.36% at the concentration of 50 ppm. These results suggest that Rhamnus yoshinoi ethanol extract has significant antioxidant activity and whitening activity.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.819-826
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• 2019

To accurately forecast the supply and demand of harbor pilots, it is necessary to derive the determinants of demand because they are directly linked to securing the safety of ships and ports. The securing of an appropriate numbers of harbor pilots can create conflicts of interest among the pilots, the Ministry of Oceans and Fisheries, and users of pilotage services as it is also a matter directly related to harbor pilots' income. Therefore, a measure is needed to ensure a suitable number of pilots can be maintained, through which high quality pilotage services can be provided. This can be achieved by deriving reasonable determinants for estimating and forecasting demand, which satisfy all stakeholders involved in pilotage service. To reveal the challenges posed by the current determinants regarding the demand for harbor pilots used by the Central Pilotage Operation Council, and arrive at solutions, this study derived three determining factors, namely the total annual average piloting time, the average working hours of pilots, and the current number of pilots. These were used to determine the demand for harbor pilots. This study used a survey and analysis of current determining factors, a questionnaire survey administered to the interested parties, a case study of selected countries, and so on, as the research methodology.

• Journal of the Korea Concrete Institute
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• v.20 no.2
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• pp.165-173
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• 2008

One of the most important requirements for reinforced concrete constructions is the bond behavior between concrete and reinforcement. For practical application, it is very important to study bond behavior of reinforcing bars in recycled aggregate concrete (RAC). Thirty six pull-out tests were carried out in order to investigate the bond behaviour between recycled coarse aggregate concrete (RCAC) and deformed bars. RCA replacement ratios (i.e., 0%, 30%, 60% and 100%) and positions of deformed bar (i.e., vertical and horizontal position) were considered as variables in this paper. Each specimen was in the form of a cube, with edges of 150 mm in length and for the pull-out tests, a deformed bar, 13 mm in diameter, was embedded in the center of each specimen. Based on the test results, the bond strength between the RCAC and deformed bars were influenced by both RCA replacement ratios and positions of deformed bars. It was found that under the equivalent mix proportion (i.e., the mix proportions are the same, except for different RCA replacement ratios), the bond strength between the RCAC and the ribbed bar has no obvious relation with the RCA replacement ratio, whereas the positions of deformed bars have a significant effect on the bond behavior between the RCAC and deformed bars. Under the condition of same RCA replacement ratio, the specimen of horizontal reinforcement at upper position (HU type) appear considerably low bond stress.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.2
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• pp.430-436
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• 2010

Since a 'Well-being' theme had become an issue in 90's, everyone now care about their health more than ever. Besides, IT has been developed so tremendously that we have various ways to collect up-to-dated information through the internet. There are so many web sites that contain information about health and diet. However, the menus of these web sites are not simplified and the content is too large, so the information we see in those web sites may not be accurate. Also, some information is out-of-dated. In this paper, we propose a web site called 'Calory&Diet' that provides customized information on diet. The characteristics of the web site are as following: First, the menu is so simple that users can easily find information they want. Second, it only provides necessary customized information. Lastly, it uses an open application that helps users always get the latest information without DB updates. With its user friendly menu and feedback information, the proposed web site can be a good advisor for people who want to be healthy. 100 offers the user survey results than existing systems, simple system to 2%, 3% from a custom-related topics, the latest related topics were 3% higher on 5 point scale.

• Journal of the Institute of Convergence Signal Processing
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• v.18 no.2
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• pp.55-61
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• 2017

In radio astronomy, high-capacity HDDs are being used to save huge amounts of HDDs in order to record the observational data. For VLBI observations, observational speeds increase and huge amounts of observational data must be stored as they expand to broadband. As the HDD is frequently used, the number of failures occurred, and then it takes a lot of time to recover it. In addition, if a failed HDD is continuously used, observational data loss occurs. And it costs a lot of money to buy a new HDD. In this study, we developed the integrity verification system of the Serial ATA HDD using FirmOS. The FirmOS is an OS that has been developed to function exclusively for specific purposes on a system having a general server board and CPU. The developed system performs the process of writing and reading specific patterns of data in a physical area of the SATA HDD based on a FirmOS. In addition, we introduced a method to investigate the integrity of HDD integrity by comparing it with the stored pattern data from the HDD controller. Using the developed system, it was easy to determine whether the disk pack used in VLBI observations has error or not, and it is very useful to improve the observation efficiency. This paper introduces the detail for the design, configuration, testing, etc. of the SATA HDD integrity verification system developed.