• KIEAE Journal
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• v.15 no.6
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• pp.57-62
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• 2015

Purpose: This study, which is based on the investment payback periods, aims to suggest the proper insulation level which can be adapted to the Defense Military Facility Criteria regarding the military residential condominiums. For the energy performance simulation, it is required to collect the residential data regarding the military condominiums and climatic data concerning the regions they belongs to. The estimates through energy performance simulation are the regional heating loads and the heating transmission coefficients of building components. Method: With the heating loads, the annual heating cost saving per square meters is assessed. With the heating transmission coefficients of building components, the additional insulation installment cost per square meters is evaluated. With two outcomes, one as an annual value and the other as a present value, the investment payback period is calculated. Result: In result, it could be concluded that 55~70% insulation ratio can lead a superior residental environments as well as be contributed to the national policy associated with zero-energy buildings because the estimated investment payback period is shorter than the life span of the military residental condominiums. This upshot can be used as a foundation to enactment the Defense Military Facility Criteria associated with military residential condominiums.

• The Journal of the Korean dental association
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• v.55 no.2
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• pp.139-155
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• 2017

The study of job satisfaction among female dentists is essential to improve the quality of their life. In this study, a job satisfaction survey of female dentists in Gwangju was performed and the factors affecting job satisfaction were examined. A survey of female dentists in Gwangju was conducted using a custom-designed and validated questionnaire which incorporated the Korean Dentist satisfaction Survey (KDSS) as well as questions regarding socio-demographics and professional characteristics. Satisfaction for each question was measured by a 5-point Likert scale. The final analysis was performed with 89 questionnaires, after excluding 3 non-response questionnaires. Analysis of the data for each group was carried out using a Mann-Whitney U test and Kruskal-Wallis H test. The reliability of the questionnaire was identified by the internal consistency of the survey using Cronbach coefficient. The data were statistically analyzed using SPSS (IBM SPSS Statistics 19, SPSS Inc, Chicago, Ill, USA). The level of statistical significance was set at p = 0.05. On analyzing with use of the above mentioned method, the following findings were observed: Income, leisure time, time for self-development, and overall job satisfaction were lower than the average, especially the percentage of dissatisfaction was much higher than that of satisfaction. Satisfaction was associated with age, duration of employment, and the number of assistants. The limitations of this study are the lack of an adequate sample size, convenience sampling during extraction, the lack of questionnaire items, the limitations of quantitative research, and failure to perform measurement in the non-response group. However, female dentists can be expected to achieve a more satisfactory and enhanced working environment if the research based on the current study is followed up in an expanded target group.

• Journal of the Korean Society for Library and Information Science
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• v.39 no.3
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• pp.139-163
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• 2005

Various corpus-based approaches, rhetorical roles of discourse structure, and unifications of similar sentences were applied to construct the automatic Ext/Sums(extracts and summaries). Rhetorical roles of sentences like objective, method, background, result, conclusion, etc. for making elastic Ext/Sums were established and extraction engines according to respective role were prepared. The $90\%$ of Success rate in extracting the important sentences of sample articles was accomplished. Rearranging the selected sentences, it used unification of similar sentences using the cosine coefficient equation, deletion of unnecessary modification and insertion clauses, junction of short sentences, and connection of sentences able to link. They suggest the methods applying rhetorical roles of sentences, meaning and signature of noun and verb in clauses, and cue words and location will be researched to construct the more effective Ext/Sums.

• Journal of the Korean Society for Library and Information Science
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• v.42 no.2
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• pp.371-392
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• 2008

The books and circulation-related data in the Online Public Access Catalog System of the H-Public library were collected and analyzed in this paper. The methods which may be applied to the Customer Relationship Management in a public library based on the results were also suggested here. Collected data were 57,927 bibliographic data of books, 11,871 patron data and 27,145 circulation records. The type of collections. circulation frequencies, total number of circulated books, publication year, and use factor as relation factor from the analyzed data of circulation records were extracted. They were also analyzed, and verified by various statistical methods such as correlation coefficient, non-parametric method, etc.

• Korean Journal of Materials Research
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• v.25 no.9
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• pp.442-449
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• 2015

The effects of coating parameters were investigated in wear resistance coatings of Diamalloy-406 on Inconel 718 to obtain an optimum coating condition by high velocity oxy-fuel spraying. The coating parameters, the flow rates of source gases (hydrogen and oxygen), the powder feed rate, and the spray distance, were designed by the Taguchi method. The optimal conditions were determined: oxygen flow rate 34 FRM, hydrogen flow rate 57 FRM, powder feed rate 35 g/min, and spray distance 7 inch. Friction coefficients of the coating and the substrate decreased with an increasing sliding surface temperature from $25^{\circ}C$ to $450^{\circ}C$. The friction coefficient of Diamalloy-4006 coating decreased as the sliding surface temperature increased from $0.43{\pm}0.01$ at $25^{\circ}C$ to $0.29{\pm}0.01$ at $450^{\circ}C$. The wear trace and wear depth of the coating were smaller than the substrate at all temperatures tested. The relationship between spray parameters and wear resistance was discussed extensively, based on the measured roughness, hardness, and porosity in each coating.

• Korean Journal of Materials Research
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• v.17 no.1
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• pp.11-17
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• 2007

Turbulent in-situ mixing process is a new material process technology to get dispersed phase in nanometer size by controlling reaction of liquid/solid, liquid/gas, flow ana solidification speed simultaneously. In this study, mixing which is the key technology to this synthesis method was studied by computational fluid dynamics. For the simulation of mixing of liquid metal, static mixers investigated. Two inlets for different liquid metal meet ana merge like 'Y' shape tube having various shapes and radios of curve. The performance of mixer was evaluated with quantitative analysis with coefficient of variance of mass fraction. Also, detailed plots of intersection were presented to understand effect of mixer shape on mixing. The simulations show that the Reynolds number (Re) is the important factor to mixing and dispersion of $TiB_2$ particles. Mixer was designed according to the simulation, and $Cu-TiB_2$ nano composites were evaluated. $TiB_2$ nano particles were uniformly dispersed when Re was 1000, and cluster formation and reduction in volume fraction of $TiB_2$ were found at higher Re.

• Magazine of the Korean Society of Agricultural Engineers
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• v.18 no.3
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• pp.4184-4194
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• 1976

Located in the southwestern part of Korea, the Yong San Gang river flows generally northeast to southwest, and because of the specific location, topography and climate, the basin area is subject to recurrent drought and flood damages. To eliminate the cause of such damages and ensure an increase in the farm income by means of effective irrigation supply and increased cropping intensity, efforts are being made to speed up implementation of an integrated agricultural development project which would include construction. of an estuary dam and irrigation facilities as well as land development and tidal reclarnation. In formulating a basin development project plan, it is necessary to study a series of long-term runoff data. The catchment area at the proposed estuary damsite is 3,471$\textrm{km}^2$ with the total length of the river channel up to this point reaching 138km. An analysis of runoff in this area was carried out. Rainfall was estimated by the Thiessen Network based on records available from 15 of the rainfall observation stations within the area. Out of the 15 stations, Kwang Ju and Mok Po stations were keeping long-term precipitation records exceeding some 60 years while the others were in possession of only 5-10 years records. The long-term records kept by those stations located in the center of the basin were used as base records and records kept by the remaining stations were supplemented using the coefficient of correlation between the records kept by the base stations and the remainder. The analyses indicate that the average annual rainfall measured at Kwang Ju during 1940-1972 (33 years) amounts to 1,262mm and the areal rainfall amounts to 1,236mm. For the purpose of runoff analysis, 7 observatories, were set up in the middle and lower reaches of the river and periodic measurements made by these stations permitted analysis of water levels and river flows. In particular, the long-term data available from Na Ju station significantly contributed to the analysis. The analysis, made by 4-stage Tank method, shows that the average annual runoff during 1940-1972 amounts to 2,189 million ㎥ at the runoff rate of 51%. As for the amount of monthly runoff, the maximum is 484.2 million ㎥ in July while the minimum is 48.3 million ㎥ in January.

• Atmosphere
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• v.25 no.2
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• pp.271-281
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• 2015

The objectives of this study are to develop a hydrological drought outlook system using GloSea5 (Global Seasonal forecasting system 5) which has recently been used by KMA (Korea Meteorological Association) and to evaluate the forecasting capability. For drought analysis, the bilinear interpolation method was applied to spatially downscale the low-resolution outputs of GloSea5 and PR (Predicted Runoff) was produced for different lead times (i.e., 1-, 2-, 3-month) running LSM (Land Surface Model). The behavior of PR anomaly was similar to that of HR (Historical Runoff) and the estimated values were negative up to lead times of 1- and 2-month. For the evaluation of drought outlook, SRI (Standardized Runoff Index) was selected and PR_SRI estimated using PR. ROC score was 0.83, 0.71, 0.60 for 1-, 2- and 3-month lead times, respectively. It also showed the hit rate is high and false alarm rate is low as shorter lead time. The temporal Correlation Coefficient (CC) was 0.82, 0.60, 0.31 and Root Mean Square Error (RMSE) was 0.52, 0.86, 1.20 for 1-, 2-, 3-month lead time, respectively. The accuracy of PR_SRI was high up to 1- and 2-month lead time on local regions except the Gyeonggi and Gangwon province. It can be concluded that GloSea5 has high applicability for hydrological drought outlook.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.420-428
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• 2010

The advancement of the Science for complex systems enables the analysis of many social networks. We constructed and analyzed a Korean movie star network as one of social networks, based on the 100 Korean movie selection for a main data source. Until now, the research trend has been the structural analysis of network, focused on link numbers, such as degree, betweenness and clustering coefficient. But it is time that the research is not limited by the structural analysis of networks only. Rather, the research goal should be aimed to an information analysis, performed by identifying and analyzing central modules that are regarded as the core of complex networks, using k-core analysis method. In this research, we constructed a network of movie stars who have appeared in 100 Korean movie selection, provided by Korean movie database, also we analyzed its core modules with and without weights, and the trend of seasonal expansion of the network. We expect our findings can be used as the basic data applicable to a model for understanding of the expansion and evolution of networks.

• Journal of Broadcast Engineering
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• v.12 no.2
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• pp.102-111
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• 2007

Currently, the efficient adaptive video streaming services and coding techniques are required to ensure quality of service (QoS) in diverse multimedia environments. To maintain optimal video quality in these environments, it is required to support scalable video coding (SVC) technique and proper QoS metric methods. In this paper, we propose a new quality metric that takes in to the temporal, the SNR, the spatial scalability on SVC. Experimental results shows that proposed method has a higher correlation with the subjective quality. We expect that the proposed metric plays an important role in deciding the coding parameter to optimize the quality of the SVC based video.