• 한국재료학회지
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• 제19권12호
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• pp.680-685
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• 2009

Using a polyurethane foam replica method, porous hydroxyapatite scaffolds (PHS) were fabricated using conventional and microwave sintering techniques. The microstructure and material properties of the PHS, such as pore size, grain size, relative density and compressive strength, were investigated at different sintering temperatures and holding times to determine the optimal sintering conditions. There were interconnected pores whose sizes ranged between about 300 ${\mu}m$ and 700 ${\mu}m$. At a conventional sintering temperature of 1100$^{\circ}C$, the scaffold had a porous microstructure, which became denser and saw the occurrence of grain growth when the temperature was increased up to 1300$^{\circ}C$. In the case of microwave sintering, even at low sintering temperature and short holding time the microstructure was much denser and had smaller grains. As the holding time of the microwave sintering was increased, higher densification was observed and also the relative density and compressive strength increased. The compressive strength values of PHS were 2.3MPa and 1.8MPa when conventional and microwave sintering was applied at 1300$^{\circ}C$, respectively.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.78-78
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• 2016

For the past three decades, extensive research has been performed in the surface design of new polymers for a variety of medical applications. Great progress in therapeutics and diagnostics can be attributed to these scientific advances in biomedical polymers. A variety of bioinert materials or bioactive materials using drugs, cells, and growth factors are widely utilized for the implants, devices and tissue regeneration. These materials provide an improved biocompatible materials to host, to significantly decrease or increase the host/tissue/blood response to the foreign materials. In the future, biomaterials will play a different role in modern therapeutics. New materials will be tailored to interact more on a protein and cellular level to achieve high degree of biocompatibility, biospecificity and bioacitivity. In this presentation, various biocompatible materials based on surface/bulk engineering will be demonstrated, which can be utilized as therapeutics implants and therapeutic vehicles for biologically active molecules such as cell, protein /peptide and gene.

• 전기학회논문지
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• 제63권9호
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• pp.1239-1244
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• 2014

In this study, two fiber-optic sensors were fabricated to measure water level and temperature using optical fibers, a coupler, a Lophine and an OTDR (optical time-domain reflectometer). First, using Fresnel's reflection generated at the distal-ends of each optical fiber, which was installed at different depth, we measured the water level according to the variation of water level. Next, we also measured the temperature of water using a temperature sensing probe based on the Lophine, whose absorbance changes with the temperature. The measurable temperature range of the fiber-optic sensor is from $5^{\circ}C$ to $65^{\circ}C$ because the maximum operation temperature of the optical fiber without a physical deterioration is up to $80^{\circ}C$.

• 센서학회지
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• 제21권5호
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• pp.367-373
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• 2012

We fabricated a fiber-optic alpha/beta detector, which is composed of a sensing probe, a plastic optical fiber, a photomultiplier tube, and a multichannel analyzer, to obtain the energy spectra of radioactive isotopes. As inorganic scintillators of a sensing probe, a ZnS(Ag) film was coupled with a $CaF_2$(Eu) crystal for alpha and beta spectroscopy. In this study, $^{210}Po$ and $^{90}Sr$ were used as alpha and beta sources, respectively, and we measured the radiation energy spectra using a fiber-optic alpha/beta detector to identify alpha and beta emitting radionuclides for nuclear medicine application. Also, the variations of energy spectrum were obtained according to the length of plastic optical fiber.

• 한국수산과학회지
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• 제48권1호
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• pp.1-15
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• 2015

Tissue engineering is an emerging, innovative technology to improve or replace the biological functions of damaged tissues and organs. Scaffolds are important materials for tissue engineering as they support cell attachment, migration, and differentiation. Marine sponges naturally contain scaffolds formed by extracellular matrix proteins (collagen and sponging) and strengthened by a siliceous or calcium carbonate skeleton. Coral skeletons are also derived naturally formed by essential calcium carbonate in the form of aragonite, and are similar to human bone. In addition, collagen extracted from jellyfish is a biosafe alternative to bovine and porcine collagen and gained attention as a potential source for tissue engineering. Moreover, cuttlefish bone is an excellent calcium source and can be used to generate bio-synthetic calcium phosphate. It has become a natural candidate for biomimetic scaffolds. This review describes the use of natural products derived from marine invertebrates for applications in bone tissue engineering based on studies from 2008 to 2014.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2003년도 somma/kms meeting
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• pp.160-160
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• 2003

• IEIE Transactions on Smart Processing and Computing
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• 제3권1호
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• pp.28-34
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• 2014

Recently, ultrasound therapy has become a new and effective treatment for many brain diseases. Therefore, skull-mimicking phantoms have been developed to simulate the skull and brain tissue of a human and allow further research into ultrasound therapy. In this study, the suitability of various skull-mimicking materials(HDPE, POM C, Acrylic) for studies of brain-tumor treatments was evaluated using focused ultrasound. The acoustic properties of three synthetic resins were measured. The skull-mimicking materials were then combined with an egg white phantom to observe the differences in the ultrasound beam distortion according to the type of material. High-intensity polyethylene was found to be suitable as a skull-mimicking phantom because it had acoustic properties and a denatured-area shape that was close to those of the skull,. In this study, a skull-mimicking phantom with a multi-layer structure was produced after evaluating several skull-mimicking materials. This made it possible to predict the denaturation in a skull in relation to focused ultrasound. The development of a therapeutic protocol for a range of brain diseases will be useful in the future.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2008년도 춘계학술발표회
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• pp.63-64
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• 2008

• 한국해양바이오학회지
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• 제13권1호
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• pp.28-47
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• 2021

Pectin is a natural polysaccharide and biopolymer that serves as a structural component of plant tissues' primary cell walls. Pectin is primarily composed of D-galacturonic acid linked by α-1, 4-glycosidic linkage and is further classified by the ratio of esterified galacturonic acid groups known as degree of esterification (DE). Pectin that contains more than half of its carboxylate units as methyl esters is known as a high methyl (HM) ester. Conversely, pectin that has less than half of its carboxylate units as methyl esters is known as a low methyl (LM) ester. Pectin has various bioactive properties, including anticancer, anti-inflammatory, antioxidant, antidiabetic, anticholesterol, antitumoral, and chemopreventive properties. Moreover, pectin is a useful biopolymer in biomedical applications. Biomedical engineering, which is founded on research aimed to improve the quality of life using new materials and technologies, is typically classified according to the use of hydrogels, nanofiber mats, and nanoparticles. This paper reviews the progress of recent research into pectin-based biomedical applications and the potential future biomedical applications of marine-derived pectin.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2004년도 동계학술연구발표회 논문개요집
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• pp.121-122
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• 2004