• Corrosion Science and Technology
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• v.19 no.4
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• pp.211-223
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• 2020

The external corrosion of buried piping can be controlled using both coating and cathodic protection. Several factors are involved in the damage and deterioration of the coating on pipes. There are many detection methods for coating defects on pipes and the direct current voltage gradient (DCVG) method is one of the most powerful methods. However, the detection reliability of DCVG can be affected by interferences such as stray current, metal objects connected to rectifiers, and copper grids. Therefore, this study focused on the interference effects of rectifiers and a copper grid on the reliability of coating flaw detection. As the length of the interference pipe connected to the rectifier increased, the reliability decreased. In contrast, as the distance between the pipe and the copper grid increased, the reliability of the coating flaw detection increased. The detection results produced by the DCVG method were discussed using current and potential simulations for a pipe with a rectifier and copper grid interference in the soil.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.77-82
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• 2004

In this paper, warpages of heterogeneous LTCC substrates comprised of high K/low K hi-layered structure were investigated. The effect of glass content in high K LTCC layer on the warpage of substrate during co-firing process was examined. Shrinkage and dielectric properties of high K and low K green sheets were measured. In-situ camber observation by hot stage microscopy showed different camber development of heterogeneous LTCC substrates according to glass content in high K green sheet. High K green sheet containing $50\%$ glass was matched to low K green sheet in the shrinkage. Therefore, LTCC substrate of Low K/High K+$50\%$ glass structure showed flat surface after sintering.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.233-236
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• 2014

Organic light emitting diodes (OLEDs) received much attention from both academia and industry as the next-generation flat panel displays. However, to produce high quality OLEDs, there are still many challenges to overcome. Especially, in full color OLEDs, the intrinsic wide band gap of the blue emitting materials results in inferior efficiency compared to those of green and red emitting materials. Therefore, extensive research efforts have been devoted to develop efficient blue emitting materials. This review briefly summarizes the basics of OLEDs and introduces highlights of research efforts in blue-emitting materials.

• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.25-33
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• 2022

This study developed the black liquor evaporation process models using the multiple-effect-evaporator according to the number of effects to predict steam consumption. The developed models were divided into the black liquor preheating and evaporation processes, and a virtual reboiler was added to predict steam consumption. In simulation results, the steam consumption in the double-effect-evaporator was decreased by 48.9 %, and as the number of effects increased, the steam consumption was decreased. Finally, the steam consumption in the octuple-effect-evaporator was decreased by 61.2 %. Also, this study suggests a strategy for deriving the optimal number of effects in the process by analyzing the latent heat recovered from the saturated vapor produced in the multiple-effect-evaporator and the amount of saturated vapor produced by each effect.

• Journal of the Korean Ceramic Society
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• v.41 no.4
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• pp.277-283
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• 2004

To fabricate green sheet of transparent dielectric for PDP front panel, dispersion of transparent dielectric slurry, density, and mechanical properties of green sheets have been investigated as a function of amount and composition of organic additives. Measurements of sedimentation and viscosity were employed to determine a proper dispersant and its amount for a well dispersed transparent dielectric powders in non-aqueous system. Green sheets, having various ratios of transparent dielectric powders to transparent dielectric powders＋ binder＋plasticizer and binder to binder＋plasticizer, were fabricated. All the tape casting slurries showed shear thinning effect, that is, the apparent viscosity decreased with the increase of shear rate. It was found that the amount and composition of organic additives were main variables to affect densities and mechanical properties of transparent dielectric green sheets for PDP.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.1
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• pp.95-107
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• 1985

This study is purposed to investigate the role of grasses as the Green Foundation effect on the visual preference to flowering tree and shrub being the principal elements of natural landscape early in the spring. As the flowering shrub materials, Rhododendron mucronulatum and Forsythia Kreana were adopted. Total 48 slides were photographed at the 8 different lawn areas with the 6 planting combinations of flowering shrub materials, and 10 landscape variables - dimensional and color - were measured and preference scores were taken by slide evaluations. The results were : 1) The visual preference to the landscape of flowering shrub in the lawn area was changed with the different lawn situations. 2) With important 4 variables, multilinear regression model was established, hence Y =40.4 + 9.6($X_1$) -7.8($X_2$) -26.8($X_3$) + 15.2($X_4$) where, Y : estimated preference score $X_1$: perimeter of flower zone $X_2$: value of green covered zone $X_3$: hue of green covered zone $X_4$: chroma of green covered zone 3) Most effective variable was 'hue of green covered zone', hence the more green the lawn area ism the more preferred landscape or the more effective green foundation is.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.359-359
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• 2006

This study deals with development of new bio-based polymeric materials from epoxidized soybean oil (ESO). The curing of ESO in the presence of organophilic montmorillonite produced an oil polymer-clay nanocomposite ("green nanocomposite") showing flexible property. A green nanocomposite (oil polymer-silica nanocomposite) coatings were synthesized by an acidcatalyzed curing of ESO with 3-glycidoxypropyltrimethoxysilane. The curing of ESO in the presence of a biodegradable plastic, poly(caprolactone), produced a composite with semi-IPN structure. The mechanical properties of the composite was much superior to those of polyESO. These new oil-based materials have large potential for applications in various fields.

• Proceedings of the Korean Magnestics Society Conference
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• 2011.06a
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• pp.36-36
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• 2011

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3919-3922
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• 2013

• Proceedings of the Korea Information Processing Society Conference
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• 2016.10a
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• pp.309-312
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• 2016

Green Internet of Things (IoT) is the study and practice of eco-friendly sustainable computing. The basic goal of green computing is to reduce the use of materials and maximize energy efficiency with reliable and secure communications. The paper presents various technologies and issues regarding green IoT. It also studies the green Information and Communication Technology (ICT) such as green M2M, green Cloud Computing (CC), and green Data Center (DC). In addition, this paper mentions about the reliability in IoT Communication and and issues to achieve green IoT communication by applying efficient activity scheduling technique for energy saving. Finally, we propose the green IoT-Home Service (GIHS) model which provides efficient energy management in home automation system.