• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.5 no.1
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• pp.55-78
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• 2001

Given the anisotropic Poisson equation $-{\nabla}{\cdot}{\mathcal{K}}{\nabla}p=f$, one can convert it into a system of two first order PDEs: the Darcy law for the flux $u=-{\mathcal{K}{\nabla}p$ and conservation of mass ${\nabla}{\cdot}u=f$. A very natural mixed finite volume method for this system is to seek the pressure in the nonconforming P1 space and the Darcy velocity in the lowest order Raviart-Thomas space. The equations for these variables are obtained by integrating the two first order systems over the triangular volumes. In this paper we show that such a method is really a standard finite element method with local recovery of the flux in disguise. As a consequence, we compare two approaches in analyzing finite volume methods (FVM) and shed light on the proper way of analyzing non co-volume type of FVM. Numerical results for Dirichlet and Neumann problems are included.

• Journal of Broadcast Engineering
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• v.11 no.4 s.33
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• pp.441-447
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• 2006

See-through HMD type 3D display can provide an advantage of us seeing virtual 3D data used stereoscopic display simultaneously with real object(MR-Mixed Reality). But, when user sees stereoscopic display for a long time, not only eye fatigue phenomenon happens but also de-focus phenomenon of data happens by fixed focal point of virtual data. Dissatisfaction of focus adjustment of eye can be considered as the important reason of this phenomenon. In this paper, We proposed an application of multi-focus in see-through HMD as a solution of this problem. As a result, we confirmed that the focus adjustment coincide between the object of real world and the virtual data by multi-focus in monocular condition.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.422-426
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• 2006

This research was conducted to get the basic materials necessary to obtain the somatic hybrid plant between Solanum sisymbriifolium and other Solanum species (S. integrifolium and S. toxicarium). Regarding the formation of colony from the protoplast in S. sisymbriifolium, S. integrifolium and the fused protoplast mixture; for the S. sisymbriifolium, a colony was observed in F medium(Kao medium containing $5.0mg{\cdot}L^{-1}\;NAA,\;1.0mg{\cdot}L^{-1}$ 2,4-D and $1.0mg{\cdot}L^{-1}$ BA); and for the S. integrifolium, in G medium (a half strength MS medium containing 0.03 M sucrose, 0.4 M mannitol, $1.0mg{\cdot}L^{-1}\;NAA,\;1.0mg{\cdot}L^{-1}$ kinetin) respectively. In mixed cultured protoplast after electriofusion treatment, the cell division and colony formation were observed in both media F and G. For the shoot and root formation rate, there was no difference between the parent of each breed and mixed protoplast regardless of the medium. In the fused protoplast mixture of S. sisymbriifolium and S. toxicarium, a colony formation was also observed in both media F and H(a half strength MS medium containing 0.03 M sucrose, 0.4 M mannitol, $1.0mg{\cdot}L^{-1}\;NAA,\;1.0mg{\cdot}L^{-1}$ kinetin); and there was no difference in the shoot and root formation rate between the parent and the mixed protoplast.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.401-404
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• 2003

In this paper, $H_2$, $H_{\infty}$, and mixed $H_2/H_{\infty}$ FIR filters are newly proposed for discrete-time state space signal models. The proposed filters require linearity, unbiased property, FIR structure, and independence of the initial state information in addition to the performance criteria in both $H_2$ and $H_{\infty}$ sense. It is shown that $H_2$, $H_{\infty}$, and mixed $H_2/H_{\infty}$ FIR filter design problems can be converted into convex programming problems via linear matrix inequalities (LMIs) with a linear equality constraint. Simulation studies illustrat that the proposed FIR filter is more robust against uncertainties and has faster convergence than the conventional IIR filters. the conventional IIR filters.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.490-499
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• 1998

This study was initiated to investigate the applicability of sludge from water or waste water treatment on the crop cultivation. Sludge is generated in the process of water and wastewater treatment process in large quantity. The sludge can cause many environmental problems. we have a many available treatment methods of sludge However, these methods still shortcomings and are not. The composition of typical municipal sludge contains organics and inorganics. The organics components are normally burnt in high temperature and mainly inorganics components are left after thermal treatment process. For the production of artificial media, chabazite was used as additive, and the mixed material was thermally treated in the firing kiln at 800~1,10$0^{\circ}C$ for about 10 minutes. The physical and chemical characteristics of artificial media were analyzed and it showed that the artificial media could be used as a media for plants and soil conditioner for farmland. The concentrations of the toxic heavy metals in the media were lower then those in the soil quality standard for farmland. This study illustrated that the artificial media production process, and introduced how to produce it's possible application as a media for Plant growth.

• Journal of Environmental Science International
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• v.14 no.12
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• pp.1163-1170
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• 2005

The microbial adsorption characteristics of two different media for biological treatment were studied using attached diverse microbes onto activated carbon and ceramic. The results in the experiments of the characteristics of physical adhesion on two different media with addition of high and low concentrated substrate in the culture were observed that the efficient of adhesion onto F-400 activated carbon was higher over that of ceramic due to the surface area of media. The irradiation treatment by ultrasonication with 400 W power and 3 min retention time on the media without addition substrate conditions and subsequent mixing throughly the culture showed the highest efficiency of cell detachment on the media. Three different microbes, P. ovalis, A calcoaceticus, and B. subtillis were used for the study of the characteristics of microbial adhesion on the media. p ovalis showed the highest adhesion capability while B. subtillis showed the lowest capability adhesion onto media either addition of substrate in the culture. The mixed bacterial culture showed $10\%$ lower removal efficiency of DOC in the low concentrated substrate culture compared to the single pure culture. Whileas, it did not show significant difference between two cultures at high concentrated substrate. It was also observed same population density of microorganism by counting of microbes adhered to microbial media with an ultrasound treatment.

• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.515-521
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• 2009

In this study, the applicability of $CaCO_3$ as a seed material for crystallization reaction was tested. $CaCO_3$ was ground to lesser than 425 mesh and was made to media mixed with binder. Batch experiment was to investigate the ${PO_4}^{3-}-P$ removal efficiency of different parameters such as $CaCO_3$ dosage and binder ratio, size, type and mass of media. In addition, the effect of phosphorus removal from wastewater was tested using a lab-scaled crystallization reactor. At the results of the batch test, phosphorus removals were improved with increasing $CaCO_3$ dosage and media mass but were decreased with increasing media size. Moreover, phosphorus removals were influenced by specific surface area but media type. The average T-P and ${PO_4}^{3-}-P$ removal efficiency in a lab-scaled crystallization reactor with $CaCO_3$ media for wastewater were shown to be 60.2% and 60.3% for 18 days of operation time.

• Broadcasting and Media Magazine
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• v.24 no.3
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• pp.35-49
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• 2019

본 고에서는 혼합현실(Mixed Reality, MR) 기반의 서비스를 위한 제작과 관련된 동향과 기술에 대해서 살펴본다. MR이란 증강현실과 가상현실의 장점을 통합하고 사용자와의 인터랙션을 더욱 강화한 방식으로 정의할 수 있는데, 이를 위해 사람에 대해 실사 형태를 가지면서 360도의 전방위 관찰이 가능한 동적인 3D모델 제작기술이 가장 핵심적인 요소이다. 특히 MR 기술 중에서 최근 5G 및 6G 기술의 시대와 함께 실사 객체 및 장면에 대한 3차원 그래픽스와 영상처리 기술을 이용한 6DoF 기반의 실사 애니메이션 제작 기술에 대해서 주로 다루고자 한다. 또한 국내외 기술적 수준을 바탕으로 국내외 시장 동향에 대해서 살펴보고, MR 기술이 시장에 미치는 파급효과와 활용 분야에 대해서도 다룬다.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.240-245
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• 2010

The objective of this study was to determine the effect of different height of drainpipe and growing media soilless cultivated cut rose in container culture. Two experiment were to examine the effect of the drainpipe height and media composition on yield and quality of cut rose, Four different drainpipe height (0, 3, 6, 9 cm) were treated to determine of optimal container type. Yield was the highest at 3 cm drainpipe height, but quality was not significantly affected by drainpipe height. Survival rate of rose was 100%, 100%, 92%, and 92%, respectively. Two different drainpipe height (0, 3 cm) and 7 media composition (pure coir and pelite, and mixed with two media 3 : 1, 2 : 1, 1 : 1, 1 : 2, 1 : 3 v/v) was treated to determine of media composition related to drainpipe height. The supply of nutrient solution was controlled by the signal of water potential at -5 kPa using frequency domain reflectometry (FDR) sensor in mixed coir with pelite 3 : 1, 1 : 1, 1 : 3 (v/v), respectively. Irrigation frequency reduced in high ratio of coir media and 3 cm height of drainpipe. Quality of cut rose except for flower weight and yield until 2nd harvest was not significantly affected by drainpipe height, but yield after 3rd was higher at 3 cm than 0 cm height of darinpipe. In the media composition, yield and qulity of cut rose was increased at high ratio of coir media.

• Journal of Fashion Business
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• v.25 no.4
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• pp.79-91
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• 2021

Currently, chatbot, a conversational platform based on artificial intelligence, is drawing attention as a new marketing channel. This study attempted to verify the effect of the anthropomorphism, message type, and media self-efficacy level on purchase intention. The experimental design of this study was a 2 (anthropomorphism level of shopping chatbot: low vs. high) × 2 (message type: factual vs. evaluative) × 2 (media self-efficacy: low vs. high) three-way mixed analysis of variance (ANOVA). This study conducted a survey by the convenience sampling method of 402 women in their 20s and 30s living in Seoul and the Gyeonggi area who were aware of chatbot services. For the final analysis, 388 questionnaires were used. Data were analyzed with the SPSS 23 program and three-way ANOVA. Simple main effects analysis was conducted. The results of this study were as follows. First, there were statistically significant differences in purchase intention according to anthropomorphism level, message type, and media self-efficacy. Second, message type and media self-efficacy showed statistically significant interaction effects on purchase intention. Lastly, anthropomorphism and the media self-efficacy level and the message type of the shopping chatbots showed significant three-way interaction effects on purchase intention.