• Advances in concrete construction
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• 제3권2호
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• pp.91-102
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• 2015

In this paper, the load-deflection analysis of the Carbon Fiber Reinforced Polymer (CFRP) strengthened Reinforced Concrete (RC) slab using Recurrent Neural Network (RNN) is investigated. Six reinforced concrete slabs having dimension $1800{\times}400{\times}120mm$ with similar steel bar of 2T10 and strengthened using different length and width of CFRP were tested and compared with similar samples without CFRP. The experimental load-deflection results were normalized and then uploaded in MATLAB software. Loading, CFRP length and width were as neurons in input layer and mid-span deflection was as neuron in output layer. The network was generated using feed-forward network and a internal nonlinear condition space model to memorize the input data while training process. From 122 load-deflection data, 111 data utilized for network generation and 11 data for the network testing. The results of model on the testing stage showed that the generated RNN predicted the load-deflection analysis of the slabs in acceptable technique with a correlation of determination of 0.99. The ratio between predicted deflection by RNN and experimental output was in the range of 0.99 to 1.11.

• Journal of Pharmaceutical Investigation
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• 제24권4호
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• pp.257-263
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• 1994

The interpenetrating polymer networks (IPNs) of polyacrylic acid (PAA)-polyethylene glycol (PEG) were synthesized via crosslinking of PEG and simultaneous free radical polymerization of PAA. The equilibrium swelling of the IPNs matrices, ranged from 40% to 95%, was varied to a great extent as compared with PAA homopolymer due to the interpolymer interaction between PAA and PEG. The drug release kinetics of drug loaded matrices was significantly affected by the charge of drugs as well as interpolymer complexation.

• 한국분말재료학회지
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• 제10권5호
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• pp.310-317
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• 2003

Two-component ceramic (alumina-zirconia) composites were fabricated by a soft-solution process in which polyethylene glycol (PEG) was used as a polymeric carrier. Metal salts and PEG were dissolved in ethyl alcohol without any precipitation in 1:1 volume ratio of alumina and zirconia. In the non-aqueous system, the flammable solvent made explosive, exothermic reaction during drying process. The reaction resulted in formation of volume expanded, porous precursor powders by a vigorous decomposition of organic components in the precursor sol. The PEG content affected the grain size of sintered composites as well as the morphology of precursor powders. The difference of microstructure in sintered composite was attribute to the solubility and homogeneity of metal cations in precursor sol. At the optimum amount of the PEG polymer, the metal ions were dispersed effectively in solution and a homogeneous polymeric network was formed. It made less agglomerated particles in the precursor sol and affected on uniform grain size in sintered composite.

• 한국인쇄학회지
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• 제16권1호
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• pp.1-11
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• 1998

Recently the study of the application of liquid crystal in industrial fields has developed rapidly. It is well known that the encapsulated liquid crystal is advantageous than raw liquid crystal for protection of surface pollution. This paper describes a new class of thermal sensor. It is that the liquid crystal polymer composite(LCPC) films consisting of a continuous LC phase embedded in a three-dimensional network of polymer matrix are formed by photopolymerization-induced phase separation. In this works, it has been demonstrated that consiste of a 8:2 mixture of chiral nematic liquid crystal and HX-620 has the greatest domain and it was best discoloration.

• 한국인쇄학회지
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• 제16권3호
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• pp.29-41
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• 1998

The ultraviolet(UV)-curable materials wildly have been used as a ink and coating materials. A according to measure UV polymerization phase separation of acryl groups 2,3,4-functional monomer, a few experiments were performed gel fraction, dynamic viscosity of alkyd resin blend system. Dependence of photoiniator concentration and various monomer, alkyd resin content investigated structural changes of films cured by UV irradiation. Curing rate measured UV irradiation under $25^{\circ}C$, cell gap 7cm and film thickness 100${\mu}{\textrm}{m}$. In results, it was through that the viscoelastic properties of films cured with increasing the ratios of monomer/alkydresin contents are network polymer in properties such as viscoelasticity.

• 한국인쇄학회지
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• 제13권1호
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• pp.93-104
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• 1995

Liquid crystal-polymer composite(LCPC) films promising new materials for both projection displays and vision product. LCPC films consist of a continous liquid crystal phase embedded in a three- dimensional network of polymer matrix. The liquid crystal in these LC phases can be elecrtrically switched giving rise to an opaque scattering off-stats and a transparent, non-scatting on- stats. In this work. a premixture is composed of LC, UV-curable monomer and photonitiator. LCPC films are formed by photopolymerization induced phase separation from this premixture. In conclusion, structure and electro-optical properties of LCPC films strongly depends on the selection of monomer, LC content and curing rate.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.220-220
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• 2006

Rheological and electrical properties of the polycarbonate (PC) / multi-walled carbon nanotube (MWNT) were studied. The MWNT was funtoinalized by treating with the hydrogen peroxide ($H_{2}O_{2}$). The electrical conductivity showed higher value for the PC/MWNT ($H_{2}O_{2}$ treated, freeze drying) composites compared that of the PC/MWNT ($H_{2}O_{2}$ treated, thermal drying) composites. From the results of the morphological, rheological, and electrical properties of the PC/MWNT composites, it is suggested that the electrical and rheological properties of the PC/MWNT composites are affected by the MWNT-MWNT network structure which is related with the MWNT morphologies such as the degree of aggregation and aspect ratio of the MWNT.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.297-297
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• 2006

Recently columnar liquid crystals have been studied due to their possible application to organic conducting materials. Supramolecular columnar liquid crystals consist of mesogenic unit which can aggregate into discs that will make up the columns which associate to form a two-dimensional network. In this study, we prepared supramolecular columnar liquid crystals containing hydrogen bonding between carboxylic acid and, pyridine moieties. Thermal and structural properties of prepared complexe were investigated, and it exhibited hexagonal columnar structure ($Col_{h}$) at room temperature.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.71-74
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• 2005

In this paper, the effects of the MWCNTs on the PTC characteristics of the conventional CB/polymer nanocomposites were investigated. For the uniform dispersion of the MWCNTs in the polymer matrix., nitricacid-treated MWCNTs were dispersed with the dissolved HOPE in the solvent. After evaporating solvent, the dried master batches in the oven were melt blended mixed with CB and HDPE to obtain the PTC materials. The initial resistivity of PTC materials decreased and the PTC intensity increased with the MWCNTs. During three repeated heating and cooling cycles, the PTC materials containing MWCNTs showed a great reproducibility due to the conductive network structures of CB particles and MWCNTs.

• Bulletin of the Korean Chemical Society
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• 제28권3호
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• pp.421-426
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• 2007

A linking ligand containing sulfur donor atoms in the terminal thiophene rings, 1,2-bis(thiophen-2-ylmethylene) hydrazine (L), was prepared by Schiff-base condensation. Ligand L reacted with [PdCl2(NCPh)2] to produce a molecular Pd compound [PdL2Cl2] (1). On the other hand, it reacted with AgNO3 and AgClO4 to produce a 2-D network [AgL0.5(NO3)] (2) and a 1-D polymer [AgL]ClO4 (3), respectively, whose structures are based on secondary intermolecular forces such as H-bonding, van der Waals interaction, and π-π stacking. Polymer 2 exhibited photoluminescence at room temperature in the solid state.