• 한국인쇄학회지
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• 제14권1호
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• pp.17-29
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• 1996

N-substituted acrylamide hydrogel is reported to have the feature of bing transparent and sensitive enough to response to a temperature stimulus below the temperature of phase transition. Especially at the near of 35 C it becomes shrunk and opaque very quickly. It has also the characteristic of reversing swelling and shrinking. The experiment showed that it is possible to produce a functional gel of super water absorption with the process of free radical polymerizing PVA(polyvinylalcohol) and PAA(polyacrylamide), and crosslinking. The ratio of shrinking and swelling caused by copolymerization rises 10% to 80% at the each temperature of 20 C, 30 C, 40 C, respectively. Phase transition temperature of this gel by copolymerization is50 C while that of ordinary N-substituted acrylamides is between 32~35 C. This temperature reaches the rearing limit of animals and plants so that volumetric transition polymer gel can be ulilized in varying fields such as agriculture/gardening which are water-using field, on-off switch sensing temperature and volumetric variation, processing of liquid wastes and civil engineering works, architecture and electronics. We have no doubt that this material will be the high-functional resin in the hi-tech age of the near future.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1995년도 추계학술대회
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• pp.173-176
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• 1995

We have developed a fast steady state free precession interferometry (SSFPI) technique which is useful for the fMRI (functional Magnetic Resonance Imaging). As is known, SSFP sequence with a suitable adjustment of gradient (readout) allows us to measure precession angle $\theta$ which is in turn related to the field inhomogeneity [1-3]. When the method is applied to the susceptibility effect based functional magnetic resonance imaging (fMRI), it was found that the direct susceptibility effect measurement was possible without perturbations such as the backgrounds and inflow effect. In this paper, simulation results and experimental results obtained with 2.0 Tesla MRI system are also presented.

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2253-2260
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• 2007

A series of tetra donor substituted [2.2]paracyclophane-based two-photon absorption (TPA) fluorophores were synthesized in neutral and cationic forms. The imaging activity of overall set of fluorophores was studied by the two-photon induced fluorescence (TPIF) method in a range of solvents. We also measured a clear progression toward a longer photoluminescence lifetime with increasing solvent polarity (intrinsic photoluminescence lifetime, τi: ~2 ns in toluene → 12-16 ns in water). The paracyclophane fluorophores with this unique property can be utilized as an optical polarity probe for the biomolecular substrates. The combined measurement of the two-photon fluorescence microscopy (TPM) cell image and TPIF lifetime can give us a better understanding of the biological processes and local environments in the cells.

• 턱관절균형의학회지
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• 제2권1호
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• pp.17-19
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• 2012

Objectives: Therapeutic effect of Yinyang Balancing Appliance of functional cerebrospinal therapy (FCST) for meridian and neurologic yinyang balance was observed in Tourette's Disorder. Methods: Two Tourette's Disorder cases were managed with the Yinyang Balancing Appliance on temporomandibular joint (TMJ), combined with acupuncture. Clinical outcome measurement was based on subjective measures and clinical observations. Results: The patients showed positive changes even after the initial treatment and this effect maintained over the follow-up period. Conclusions: Although it is not clear the effect is a sustaining or temporary in its nature, a positive effect was observed and further clinical and biological research on FCST is expected.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1349-1354
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• 2008

In this study, we try to find the root cause of water condensing failures in a headlamp using chemical and mechanical analysis. Through the surface inspection by OM, SEM and CT, it was found that water infiltrate into the headlamp through hotmelt adhesive debonding part caused by adhesion force degradation and poor quality. IR spectra shows that adhesion force degradation are characterized by increase of some functional group(1742, 1710, 1649, 1016). Through the ESPI measurement, it is turned out that bonding structural change by thermal expansion and degradation of adhesive can be the cause of void generation. So it is recommended that cooling passage and the bonding part should be redesigned to give a guarantee of less thermal stress and high adhesion quality.

• 턱관절균형의학회지
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• 제1권1호
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• pp.19-22
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• 2011

Objectives: Therapeutic effect of Yinyang Balancing Appliance of functional cerebrospinal therapy (FCST) for meridian and neurologic yinyang balance was observed in dysarthria with dystonia cases. Methods: Two dysarthria with dystonia cases were managed with the Yinyang Balancing Appliance on temporomandibular joint (TMJ), combined with acupuncture. Clinical outcome measurement was based on subjective measures and clinical observations. Results: The patients showed positive changes even after the initial treatment and this effect maintained over the follow-up period. Conclusions: Although it is not clear the effect is a sustaining or temporary in its nature, a positive effect was observed and further clinical and biological research on FCST is expected.

• 턱관절균형의학회지
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• 제4권1호
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• pp.17-20
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• 2014

Therapeutic effect of Yinyang Balancing Appliance of functional cerebrospinal therapy (FCST) for meridian and neurologic yinyang balance was observed in primary dysmenorrhea cases. Two primary dysmenorrhea cases were managed with the Yinyang Balancing Appliance on temporomandibular joint (TMJ), combined with acupuncture. Clinical outcome measurement was based on subjective measures and clinical observations. The patients showed positive changes even after the initial treatment and this effect maintained over the follow-up period. Although it is not clear the effect is a sustaining or temporary in its nature, a positive effect was observed and further clinical and biological research on FCST is expected.

• Macromolecular Research
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• 제17권9호
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• pp.697-702
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• 2009

Mesoporous ethanesilica thin film was prepared using PEO-PLGA-PEO triblock copolymers as structure-directing agents and (1,2-bis(triethoxysilyl) ethane BTESE; bridged organosilicates) as inorganic precursors via one-step sol-gel condensation of ethanesilica precursors. The mesostructure of ethanesilica films is critically dependent on the processing experimental parameters after the hydrolyzed silica sol mixture was spin-cast. This study examined the effects of the block copolymer template/organosilica precursor ratio in the casting solution and aging period before calcination of the mesostructure. It was further demonstrated that mesoscopic ordering of organosilicate thin films is induced by the rearrangement of block copolymer template/organosilica hybrid during thermal decomposition of the PEO-PLGA-PEO triblock copolymer. The mesoporous structure and morphology were characterized by SAXS, TEM and solid-state NMR measurement.

• 소성∙가공
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• 제11권7호
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• pp.561-568
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• 2002

Micro tensile test is the most direct and convenient method to measure material properties such as Young's modulus and fracture strength. It, however, needs more accurate measurement system, mote stable and repetitive alignment and more sensitive gripping than conventional tensile test. Many researchers have put their effort on overcoming these difficulties for tile development of micro tensile tester, fabricating micro specimens of functional materials and measuring their properties. This paper will review the related vigorous researches over the world in the recent decade and explain how to apply them to a design of the fester which is under our own development.

• 통합자연과학논문집
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• 제13권1호
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• pp.13-18
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• 2020

This study used cerium iron hydroxide nanoparticle with HEMA (2-hydroxyethyl methacrylate), the cross-linker EGDMA (ethylene glycol dimethacrylate), NVP (N-vinyl-2-pyrrolidone) and the initiator AIBN (azobisisobutyronitrile) for copolymerization. Also, the physical properties of the prepared lenses were compared, and their applicability as polymers for ophthalmic materials was experimented. The results of the measurement showed that the UV blocking rate and the wettability increased with the cerium iron hydroxide nanoparticles addition ratio, and the refractive index and water content were not affected. Thus, the produced copolymer is expected to be useful as a functional contact lens material while satisfying the basic physical properties of the hydrogel contact lens.