• Resources Recycling
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• v.29 no.3
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• pp.11-23
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• 2020

This study aims to investigate breakage and liberation characteristics of iron ore from Shinyemi mine, Jeongseon by ball mill. Parameters of breakage functions for three grade samples of iron ore were obtained using single-sized-feed breakage test and back-calculation based on nonlinear programming. The results showed that with the increase in the grade of iron ore, the breakage rate factor decrease whereas the particle size sensitivity decreases. This results from retardation of microcrack-propagation by magnetite grain in the ore. Breakage distribution analysis showed that the breakage mechanism appear to be impact fracture dominant with the increase of grade owing to the stress distribution effect by magnetite grain. Degree of liberation (DOL) increased with the increase in grade and decrease in particle size, respectively. Using the breakage function and size-DOL relationship, a model that can predict time-dependent-DOL is established. When scale-up factors from operating condition are available, the model is expected to be capable of predicting size and DOL with time in actual mining process.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.10
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• pp.1695-1706
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• 2001

본 연구는 조선시대 남자 포제(포제에 나타난 복식이미지의 구성요인을 밝히고 남자포제 유형별(철릭, 답호, 직령, 도포, 창의, 주의), 시기별(전기, 중기, 후기) 복식이미지를 알아봄으로서 조선시대 남자포제가 가진 복식이미지를 밝혀 현대 전통복식 디자인에 응용될 수 있는 기초적인 자료를 제공하고자 한다. 의복 자극물은 남자 평상복을 중심으로 하여 조선초기(1477년∼1543년)의 남자 포제로는 철릭, 답호, 직령 3점과 조선중기(18세기)는 도포, 창의 2점, 조선후기(17세기 후기∼20세기 초)는 주의 1점으로 하였고, 당 시대의 정화한 복식이미지를 살펴보기 위해 유물을 복원 제작하여 사용하였다. 이것을 모델에게 착장시켜 슬라이드로 제작한 후 자극물로 제시하였다. 의미지분척도외 구성은 자유언어연상법으로 형용사를 수집하여 23쌍의 형용사쌍을 구성하였다. 패널단은 대학생 남·여 총 600명으로 하였고 자료분석은 SAS을 이용하여 요인분석 분산분석 등을 사용하였다. 1. 조선시대 남자 포제의 요인구조는 품위성 요인(25.2%), 활동성 요인(l4.2%), 관할성 요인(37.9%), 현시성 요인(6.7%), 경연성 요인(5.7%)으로 구성되었으며, 이들 5개 요인의 전체변량 62.7% 중에서 품위성 요인, 활동성 요인, 관할성 요인이 전체변량의 50%를 넘어서 이 세 요인이 남자 포제에서 기본적으로 느껴지는 중요한 요인임을 알 수 있다. 2. 조선시대 남자 포제 유형별 복식이미지의 차이를 알아본 결과, 철릭은 가장 부자연스러운, 주름있는, 곡선적인, 부드러운, 특이한 이미지의 포제로 나타났으며, 답호는 가장 절제된, 직선적인 딱딱한, 특이한 이미지로, 직령은 가장 비활동적인, 답답한, 전통적인 이미지로 도포는 가장 품위있는. 관할한 이미지로 창의는 다른 포제에 비해 평범한, 단순한, 이미지로 주의는 가장 품위 없는, 일상적인, 활동적인, 단순한, 순수한 이미지의 포제로 평가되었다. 모든 남자포제가 전통적, 순수한 이미지의 포제로, 철릭을 제외한 모든 포제가 단순한 이미지로 나타나 조선시대 남자 포제가 공통적으로 가지는 이미지는 단순하고 순수한 이미지를 가지고 있음을 알 수 있다. 3. 남자 포제의 시기별 복식이미지에서는 조선전기(철릭, 답호, 직령)의 포제는 관할성 요인이 높은 의례적인, 관할한, 특이한 이미지로 평가되었고 조선중기(도포, 창의)의 포제는 품위있는, 절제된, 풍성한 이미지로 평가되었으며, 조선후기(주의)의 포제는 활동적인, 단순한, 직선적인 이미지로 나타났다. 따라서 시대별 남자 포제의 이미지는 시대적 여건과 상황에 따라 변화되어 왔으며, 시대에 따라 추구하는 이미지가 달랐다는 것을 알 수 있다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.354-363
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• 2016

This study examined the relationships among levels of knowledge, attitude and preventive behavior regarding tuberculosis in service workers. The survey period was 1 - 7 October, 2015 with service workers who work in large scale stores in Jeonnam. The collected data were analyzed using an independent t-test, ANOVA, and Pearson's correlation coefficients using the SPSS WIN 12.0 program. The mean score for knowledge about tuberculosis was $14.05{\pm}6.39$, the mean score of attitude toward tuberculosis was $29.87{\pm}4.89$ and the mean score of preventive behavior for tuberculosis was $31.44{\pm}4.86$. Preventive behavior was found to have significant relationships with gender, marital status, smoking, job satisfaction, and subjective health status. A slightly positive correlation was observed between the knowledge of tuberculosis and the attitudes toward tuberculosis. A positive correlation was noted between the attitude toward tuberculosis and preventive behavior for tuberculosis, while there was a negative correlation between the preventive behavior and age. Therefore, is necessary to consider the related factors for the development and implementation of systematic education programs that can encourage and promote preventive behavior for tuberculosis among service workers.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.10
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• pp.1277-1286
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• 2018

In this paper, we provide flexible scalability of computing resources in cloud environment and Apache Hadoop based cloud environment for analysis of public medical information big data. In fact, it includes the ability to quickly and flexibly extend storage, memory, and other resources in a situation where log data accumulates or grows over time. In addition, when real-time analysis of accumulated unstructured log data is required, the system adopts Hadoop-based analysis module to overcome the processing limit of existing analysis tools. Therefore, it provides a function to perform parallel distributed processing of a large amount of log data quickly and reliably. Perform frequency analysis and chi-square test for big data analysis. In addition, multivariate logistic regression analysis of significance level 0.05 and multivariate logistic regression analysis of meaningful variables (p<0.05) were performed. Multivariate logistic regression analysis was performed for each model 3.

• The Korean Journal of Applied Statistics
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• v.28 no.2
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• pp.343-351
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• 2015

We introduce how to fit random effects models via a SRC-Stat statistical package. This package has been developed to fit double hierarchical generalized linear models where mean and dispersion parameters for the variance of random effects and residual variance (overdispersion) can be modeled as random-effect models. The estimates of fixed effects, random effects and variances are calculated by a hierarchical likelihood method. We illustrate the use of our package with practical data-sets.

• Korean Security Journal
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• no.16
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• pp.101-118
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• 2008

The subjects in this study were 500 students who were selected from a population that consisted of security majors who took courses in martial arts in four different four-year-course universities. After a survey was conducted, the answer sheets from 451 students were analyzed except 49 incomplete ones. The collected data were analyzed with SPSS Ver. 12.0 program. Frequency analysis, t-test and one-way ANOVA were utilized, and LSD and regression analysis were employed to make a post-hoc comparison. All the hypotheses formulated in this study were verified at the a=.05(Chronbach's alpha) level of significance. The findings of the study were as follows: First, as for relations between demographic characteristics and self- realization, the college students investigated were statistically different according to gender in three subvariables of self-realization that included ability development, ability display and attainment of ideal. Age and academic year made a significant difference to their ability development and attainment of ideal, and they differed statistically significantly in terms of ability development according to black lebel test. Second, concerning connections between the degree of martial-arts training and self-realization, training term, one of the subvariables of the degree of martial-arts training had a positive correlation to their ability development and attainment of ideal at the 5% level of significance, and training time was positively correlated to their ability development at the 5% level of significance. Third, training term, one of the subvariables of the degree of martial- arts training, had an impact on ability development, and that exerted a firsthand influence on attainment of ideal as well.

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.1-8
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• 2006

The objective of this study is to assess impacts of sorption heterogeneity on the transport of leachate leaked from unlined landfill sites and is accomplished by examining the results from a series of Monte-Carlo simulations. For random distribution coefficient ($K_{d}$) fields with four different levels of heterogeneity ranging from homogeneous to highly heterogeneous, the transport of leachate was investigated by linking a saturated flow model with a contaminant transport model. Impacts of a chemical heterogeneity were evaluated using point statistics values such as mean, standard deviation, and coefficient of variation of the concentration obtained at monitoring wells from 100 Monte-Carlo trials. Inspection of point statistics shows that the distribution of distribution coefficient in the landfill site proves to be an important parameter in controlling leachate concentrations. In comparison to homogeneous sorption, heterogeneous $K_{d^-}$ fields produce the variability in the leachate concentration for different realizations. The variability increases significantly as the variance in the $K_{d^-}$ field and the travel time between source and monitoring well increase. These outcomes indicate that use of a constant homogeneous $K_{d}$ value for predicting the transport of leachate can result in significant error, especially when variability in $K_{d}$ is high.

• Journal of the Korean Vacuum Society
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• v.9 no.3
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• pp.227-232
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• 2000

$MgTiO_3$thin films have been grown on various substrates by pulsed laser deposition (PLD) to investigate the application for microwave dielectrics and optical devices. Epitaxial $MgTiO_3$thin films were obtained on sapphire (c-plane$A1_2O_3$$MgTiO_3$thin films deposited on $SiO_2/Si$ and platinized silicon ($Pt/Ti/SiO_2/Si$) substrates were highly oriented. $MgTiO_3$thin films grown on sapphire were transparent in the visible and had a sharp absorption edge about 290 nm. These $MgTiO_3$thin films had extremely fine feature of surface morphology, i.e., rms roughness of 0.87 nm, which was examined by AFM. We have investigated the dielectric properties of the $MgTiO_3$thin films in $MIM(Pt/MgTiO_3/Pt)$ capacitors. Dielectric constant and loss of $MgTiO_3$thin films deposited by PLD were about 24 and 1.5% at 1 MHz, respectively. These $MgTiO_3$thin films also exhibited little dielectric dispersion.

• Applied Chemistry for Engineering
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• v.23 no.2
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• pp.222-227
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• 2012

In this study, nano-emulsion containing ethyl acetate fraction of Polygonum aviculare (P. aviculare) extract was prepared and skin permeability of the nano-emulsion was evaluated. Nano-emulsion was prepared using homogenizer and microfluidizer by the high-energy method. The droplet size and loading efficiency of nano-emulsion containing ethyl acetate fraction of P. aviculare extract were determined. The mean droplet size was 238 nm and the loading efficiency was more than 98%. The size distribution of nano-emulsion was a monodispersed form and nano-emulsion was more stable than that of using typical emulsion without using the microfluidizer. The in vitro skin permeation study of nano-emulsion containing ethyl acetate fraction of P. aviculare extract was carried out using Franz diffusion cells. Compared to 1,3-butylene glycol, nano-emulsion showed greater values of cumulative permeation of ethyl acetate fraction from P. aviculare extract. These results indicate that the stability and skin permeability of nano-emulsion containing ethyl acetate fraction of P. aviculare exerting anti-oxidative and anti-aging activities were enhanced.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.1
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• pp.75-84
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• 2012

Mechanized operation model and mechanical cultivation technology for winter barley, rye, Italian ryegrass and sudan grass wrap silage production system at the paddy field for cropping system was developed. Also, a series of experiment were performed and lots of data were collected and analyzed to develope mechanical technology, coverage area, and optimum size of the farm (break-even point) for wrap silage production system. The coverage area for winter barley or rye wrap-silage production system is determined around 61.9, 73.4, 77.5, 88.2 ha in the case of drill seeding and different ripening species by tractor power 50, 75, 100, 130 ps, respectably. The break-even point of the farming size is analyzed as 20 ha and its production cost is estimated around 367, 383, 430, 443 won/TDN-kg in the case of winter barley wrap-silage by tractor power 50, 75, 100, 130 ps, respectably. The break-even point of the farming size is analyzed as coverage area and its production cost is estimated around 237, 215 won/TDN-kg in the case of winter barley wrap silage and sudan grass by the tractor power 50, 100 ps, respectably.