• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.138-149
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• 2003

Korean regional network of tower flux sites, KoFlux, has been initiated to better understand $CO_2$, water and energy exchange between ecosystems and the atmosphere, and to contribute to regional, continental, and global observation networks such as FLUXNET and CEOP. Due to heterogeneous surface characteristics, most of KoFlux towers are located in non-ideal sites. In order to quantify carbon and energy exchange and to scale them up from plot scales to a region scale, applications of various methods combining measurement and modeling are needed. In an attempt to infer regional-scale flux, four methods (i.e., tower flux, convective boundary layer (CBL) budget method, MM5 mesoscale model, and NCAR/NCEP reanalysis data) were employed to estimate sensible heat flux representing different surface areas. Our preliminary results showed that (1) sensible heat flux from the tower in Haenam farmland revealed heterogeneous surface characteristics of the site; (2) sensible heat flux from CBL method was sensitive to the estimation of advection; and (3) MM5 mesoscale model produced regional fluxes that were comparable to tower fluxes. In view of the spatial heterogeneity of the site and inherent differences in spatial scale between the methods, however, the spatial representativeness of tower flux need to be quantified based on footprint climatology, geographic information system, and the patch scale analysis of satellite images of the study site.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.6C
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• pp.495-505
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• 2010

In this paper, the effect of Near-Far Problem (NFP) among distributed nodes in OFDMA-based Wireless Mesh Networks (WMNs) is analyzed by investigating statistical characteristics of Time Difference of Arrival (TDoA) and Desired-to-Undesired power Ratio (DUR). In order to overcome the effects of Inter-Symbol Interference (ISI), Inter-Carrier Interference (ICI), and Inter Link Interference (ILI), caused by TDoA in WMNs, we derive effective SINR for each subcarrier, and then, propose the optimal starting point of FFT window which can minimize BER for each subcarrier. In addition, we propose a subcarrier-based Zero Forcing - 2 Dimensional Ordered Successive Interference Cancellation (ZF-2DOSIC) technique for signal detection in WMNs with TDoA. It is verified by simulation that the effective SINR and uncoded BER performances of the proposed signal detection technique for OFDMA-based WMNs are significantly improved, compared with those of conventional technique.

• Journal of the Korean Solar Energy Society
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• v.32 no.4
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• pp.24-33
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• 2012

Recently, finishing materials at spandrel area, a part of curtain-wall system, are gradually forced to improve thermal insulation performance in order to enhance the building energy efficiency. Also, Building Integrated Photovoltaics(BIPV) systems have been installed in the exterior side of the spandrel area, which is generally composed of windows. Those BIPVs aim to achieve high building energy efficiency and supply the electricity to building. However, if transparent BIPV module is combined with high insulated spandrel, it would reduce the PV efficiency for two major reasons. First, temperature in the air space, located between window layer and finishing layer of the spandrel area, can significantly increase by solar heat gain, because the space has a few air density relative to other spaces in building. Secondly, PV has a characteristics of decreased Voltage(Voc and Vmp) with the increased temperature on the PV cell. For these reasons, this research analyzed a direct interrelation between PV Cell temperature and electricity generation performance under different insulation conditions in the spandrel area. The different insulation conditions under consideration are 1) high insulated spandrel(HIS) 2) low insulated spandrel(LIS) 3) PV stand alone on the ground(SAG). As a result, in case of 1) HIS, PV temperature was increased and thus electricity generation efficiency was decreased more than other cases. To be specific, each cases' maximum temperature indicated that 1) HIS is $83.8^{\circ}C$, 2) LIS is $74.2^{\circ}C$, and 3) SAG is $66.3^{\circ}C$. Also, each cases yield electricity generation like that 1) HIS is 913.3kWh/kWp, 2) LIS is 942.8kWh/kWp, and 3) SAG is 981.3kWh/kWp. These result showed that it is needed for us to seek to the way how the PV Cell temperature would be decreased.

• Journal of the Korean Dietetic Association
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• v.12 no.4
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• pp.313-328
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• 2006

This study was objectively performed to identify dietitians' job in the elderly health-care facilities, to assess facilities and dietitian's demographic characteristics, and to determine performance and importance of dietitian's job including the demand of therapeutic diet development. Survey was conducted by mail and samples were the dietitians working in 376 facilities which capacity is over 50 members from nationwide 583 the elderly health-care facilities. Returned questionnaire was 102 and used for statistic analysis. The distributions of the elderly health-care facilities showed 39 the elderly nursing facilities(38.2%), 32 skilled nursing facilities (32.4%), 13 geriatrics hospital facilities(12.7%) and 9 the elderly cost nursing facilities(8.8%). 60.0 percent of the samples showed its menu price as 1,000 to 1,500 won. A cycle-menu program was in-use at the 79.0% facilities, but only 7.1% facilities have been introduced a selected menu system. 92.9% facilities employed only one dietitian. In the demographic characteristics of dietitian only 14.7% dietitian had a clinical dietitian license and 51.5% of respondents answered at least 1 to 3 months internship program is needed. Job activities of the dietitian in the elderly health-care foodservice were identified as 45 activities with 9 dimensions. Job performance score evaluated dietitian oneself was 4.71 of 7 points. The average importance score that the dietitian evaluated their own job was 5.66 points of 7. The job activities shown higher importance but lower performance were therapeutic diet development for in-patients, menu development suitable for taste of the elderly, and leadership. Job performance score by characteristics of dietitian and their elderly health-care facilities was significantly associated with experience of dietitian in elderly health-care (F=4.480, p<0.05), education of dietitian(F=2.659, p<0.01), number of dietitian(F=2.245, p<0.05), and number of employee in foodservice(F=2.607, p<0.05). Most common diseases of the aged was proved as hypertension(81.7%), diabetes mellitus(71.4%), and dementia(65.0%). The therapeutic diets frequently provided were diabetes mellitus diet, dysphagia diet, low sodium diet, high fiber diet, and high protein diet, in order. For those reasons, dietitian in the elderly health care emphasized that the information about therapeutic diet development such as diabetes mellitus diet, dysphagia diet, low sodium diet and hypertension diet must be continuously developed and provided. The result from this study can be applicable to enlarge and enrich job activities of dietitian in elderly health-care foodservice.

• Land and Housing Review
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• v.2 no.1
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• pp.61-68
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• 2011

In order to clarify the structural performances of Welded Deformed Steel Bar Mats (WDSBM), the research stated includes the tests for standard hook of top bars of slab in concrete slab-wall joints, the tests for embedment length of top bar of slab, and the development strength tests for standard hook. The test results are as follows; (1) For slab-wall joints using WDSBM as reinforcement in slab, if the top bars of WDSBM are spliced by ordinary bars with sufficient development length and size, it is enough for the strength and crack control. (2) When WDSBM of slab is spliced in joint, the strength is increased with the embedment of bars of this WDSBM into wall. Beyond peak strength, however, ductility is diminished to that as no splice due to pull-out failure. (3) For slab-wall system, ultimate strain of concrete for flexural compression zone in lower surface of slab seems much greater than that of normal concrete beam. The reason is that normal concrete beam has the joint with $180^{\circ}$, however slab-wall joint has the $90^{\circ}$ of which concrete can be confined.

• The Journal of the Korea Contents Association
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• v.18 no.6
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• pp.155-168
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• 2018

The purpose of this study was to investigate characteristics of Blockchain to introduce Blockchain technology to the medical industry. Thus, the 5 factors such as Security, Availability, Reliability, Diversity and Economic feasibility were used as the characteristics of Blockchain, which are independent variable, based on precedent studies. Also, Technology Acceptance Model(TAM) that are widely used in the research on Acceptance Intention in order to introduce new technology accept was utilized for intervening variable and dependent variable. For the purpose of this study, the health professionals and ordinary people were classified into health care providers and medical service consumers respectively to conduct survey and comparative analysis. The researching findings discovered that Hypothesis1-1(Security-Perceived Easiness-Acceptance Intention), Hypothesis2-1(Security-Perceived Usefulness-Acceptance Intention) and Hypothesis 3-1(Security-Perceived Easiness-Perceived Usefulness-Acceptance Intention) were rejected in all participants including health professionals and ordinary people. Additionally, all characteristics of Blockchain such as Availability, Reliability, Diversity and Economic feasibility were rejected in Hypothesis3-2 and Hypothesis 3-5 that pass through Easiness and Usefulness to Acceptance Intention, in case of the medical service consumers. Thus, this study discovered and confirmed that there's difference between the health care providers and medical service in the characteristics of Blockchain, as they pass through Perceived Easiness and Perceived Usefulness to Acceptance Intention. The significance of this study can be found, as it suggested activation plan through empirical analysis, which was hardly ever used in the study on Blockchain activation.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.1
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• pp.55-60
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• 2012

In order to develop electroless-plated Nickel Phosphate (Ni-P) as a contact material for high efficient low-cost silicon solar cells, we evaluated the effect of ambient thermal annealing on the degradation behavior of interfacial adhesion energy between electroless-plated Ni-P and silicon solar cell wafers by applying 4-point bending test method. Measured interfacial adhesion energies decreased from 14.83 to 10.83 J/$m^2$ after annealing at 300 and $600^{\circ}C$, respectively. The X-ray photoelectron spectroscopy analysis suggested that the bonding interface was degraded by environmental residual oxygen, in which the oxidation inhibit the stable formation of Ni silicide phase between electroless-plated Ni-P and silicon interface.

• Korean journal of communication and information
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• v.46
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• pp.387-419
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• 2009

The concept of strategic group is defined as an aggregate of corporations utilizing similar strategies with similar resources. It becomes a kinds of contact point in the middle of corporation and industry between the industrial organization theory and the strategic management theory. This study tried to apply the strategic group model, which has been a main theory in the management studies, to program providing industry in Korea. This study shed lights upon research problems such as number of strategic groups, differences of strategic variables among the groups, finally differential performances according to strategic groups. 40 commercial broadcasting companies were analyzed to find answers. 9 strategic groups were drawn as a result of cluster analysis. Major variables which contribute to making groups were operating efficiency(4.05), pricing(3.83), size(number of system operator, 3.56), reliance on license revenue(2.58), horizontal integration(number of sister networks, 2.16) in order. An analysis of variance between performance variables has shown statistical significance regarding total net revenue per subscriber, however, insignificances statistically in regards to ratio of operating profit to net sales, cash Abstracts 687 flow ratio. Some studies in the past insisted that history variable played an important role to classifying strategic groups. However, this study found that the history didn't exert significant influence on either the group classification itself or performance.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.4
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• pp.377-383
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• 2013

This study examined the radiopacity of eight contemporary luting cements by direct digital radiography. Five disc-shaped specimens ($5mm{\times}1mm$) were prepared for each material tested (BisCem, Clearfil SA Luting, Duolink, Maxcem Elite, Multilink Speed, Panavia F 2.0, RelyX Unicem Clicker, V-link). The specimens were radiographed using a Kodak CS 7600 image plate (Carestream Health, Inc., Rochester, NY, USA) and an aluminum step wedge with a range of thicknesses (1.5 to 16.5 mm in 1.5 mm increments) and a 1 mm tooth used as a reference. A dental X-ray machine Kodak 2200 Intraoral X-ray System (Carestream Health, Inc., Rochester, NY, USA), operating at 70 kVp, 4 mA, 0.156 s and a source-to-sample distance of 30 cm, was used. According to international standards, the radiopacity of the specimens was compared with that of an aluminum step wedge using NIH ImageJ software (available at http://rsb.info.nih.gov/ij/).The data was analyzed by ANOVA and a Tukey's post hoc test. Maxcem Elite (5.66) showed the highest radiopacity of all materials, followed in order by Multilink Speed (3.87) and V-link (2.83). The radiopacity of Clearfil SA Luting (1.35), BisCem (1.33), Panavia F 2.0 (1.29) and Duolink (1.10) were between enamel (1.79) and dentin (0.19). RelyX Unicem Clicker (0.71) showed the lowest radiopacity, which was higher than that of dentin. All materials showed a radiopacity above the minimum recommended by the International Organization for Standardization and the American National Standards/American Dental Association with the exception of RelyX Unicem Clicker.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.494-500
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• 2012

In order to determine the functional benefits of $Cordyceps$ $militaris$ in the immune system, we examined the immunomodulatory activities of $Cordyceps$ $militaris$ in an immunocompromised C57BL/6 mice model. Mice were injected intraperitoneally with an immunosuppressive drug, cyclophosphamide, and then administered orally with 3% hydroxypropylmethylcellulose or 30, 100, and 300 mg/kg of 50% ethanol extract of $Cordyceps$ $militaris$ (CM 30, CM 100, and CM 300, respectively) for 12 days. Mice treated with CM displayed significantly increased splenocyte proliferation and natural killer cell activity compared to immunosuppressed control mice (p<0.05). The spleen cells isolated from mice treated with CM also displayed increased production of Th1 cytokines, including IL-2, IL-12, IFN-${\gamma}$ and TNF-${\alpha}$, suggesting enhanced cellular immunity in response to CM. However, CM had no significant effect on the production of IL-4 and IL-10. These results indicate that $Cordyceps$ $militaris$ enhances immune function by promoting immune cell proliferation and Th1 cytokine production.