• Food Science and Biotechnology
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• 제16권2호
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• pp.212-217
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• 2007

Fucoidan (fucan sulfate) is a fucose-containing sulfated polysaccharide from brown algae such as Fucus vesiculosus, Ecklonia kurome, and Cladosiphon okamuranus. The aim of this study was to investigate the effect of fucoidan on the expression of diabetes-related genes in mouse cell line 3T3-L1. 3T3-L1 adipocytes were cultured for 48 hr with or without fucoidan (10, 100, and 500 ppm) on a 60 mm dish. Reverse transcription polymerase chain reaction (RT-PCR) was used for measurement of peroxisome proliferators activated receptor ${\gamma}\;(PPAR{\gamma})$, CCAAT/enhancer binding protein ${\alpha}\;(C/EBP{\gamma})$, and glucose transporter 4 (GLUT4) RT-PCR analysis revealed that expression level of GLUT4, $PPAR{\gamma}$, and $C/EBP{\alpha}$ mRNAs increased with fucoidan treatment from 10 to 500 ppm in a dose-dependent manner. Fucoidan appears to enhance insulin sensitivity by increasing the expression level of diabetes-related genes in 3T3-L1 adipocytes. Therefore, fucoidan is potentially useful as a natural therapeutic material for hyperglycemia in type II diabetes patients.

• 한국재료학회지
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• 제23권11호
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• pp.620-624
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• 2013

Nanocrystalline materials have recently received significant attention in the area of advanced materials engineering due to their improved physical and mechanical properties. A solid-solution nanocrystalline powder, (Ti,Mo)C, was prepared via high-energy milling of Ti-Mo alloys with graphite. Using XRD data, the synthesis process was investigated in terms of the phase evolution. Rapid sintering of nanostuctured (Ti,Mo)C hard materials was performed using a pulsed current activated sintering process (PCAS). This process allows quick densification to near theoretical density and inhibits grain growth. A dense, nanostructured (Ti,Mo)C hard material with a relative density of up to 96 % was produced by simultaneous application of 80 MPa and a pulsed current for 2 min. The average grain size of the (Ti,Mo)C was lower than 150 nm. The hardness and fracture toughness of the dense (Ti,Mo)C produced by PCAS were also evaluated. The fracture toughness of the (Ti,Mo)C was higher than that of TiC.

• Elastomers and Composites
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• 제51권1호
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• pp.24-30
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• 2016

Sole in the footwear usually modified with foaming agent on the polymer resin to improve the lightweightness and crush-cushion effect. In this study, we investigated rheological properties for polymer resin filled with the different type and concentration of foaming agent, capsule type foaming agent and organo-chemical foaming agent, under the time sweep test. Curing times of each polymer resin with different kind of foaming agent are delayed than reference material (epoxy resin with curing agent). In case of adding capsule type foaming agent, however, there is appropriate concentration to reduce the curing time, relatively. When foaming agent is activated, foaming force inflates the sample in contrast to condensation force of curing and then axial normal force develop to the (+) direction. Interestingly, by increase concentration of foaming agent, there is a specific point to break down the axial normal force development. The reason for this phenomenon is that coalescence of foams induce the blocking of axial normal force development.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2004년도 춘계학술대회
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• pp.247-257
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• 2004

Electrodes were fabricated based on activated carbon powder BP-20, conducting agent such as Super P, vapor grown carbon fiber (VGCF) and acetylene black (AB), and the mixed binders of flexible poly(vinylidenefluoridehexafluoropropylene) [P(VdF-co-HFP)] and cross linking dispersion agent of polyvinylpyrrolidone (PVP) to increase mechanical strength. According to impedance measurement of the electrode with the addition of conducting agent, we found that it was possible to charge rapidly by the fast steady-state current convergence due to low equivalent series resistance (AC-ESR, fast charge transfer rate at interface between electrode and electrolyte and low RC time constant. The self-discharge of unit cell showed that diffusion process was controlled by the ion concentration difference of initial electrolyte due to the characteristics of Electric Double Layer Capacitor (EDLC) charged by ion adsorption in the beginning, but this by current leakage through the double-layer at the electrode/electrolyte interface had a minor effect and voltages of curves were remained constant regardless of electrode material. We found that the 2.3V/230F grade EDLC would be applied to industrial safety usage such as uninterrupted power supply (UPS) because of the constant DC-ESR by IR drop regardless of discharge current.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.797-800
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• 2008

시멘트 사용량을 줄이기 위한 방법으로 포졸란 반응재료들이 혼화재로 사용되고 있다. 우리나라 전역에 널리 매장되어 있는 황토는 친환경 재료로서, 포졸란 반응을 하는 활성황토는 콘크리트의 혼화재로 활용성이 증가하고 있다. 또한 PET보강섬유는 폐 PET병을 재활용하여 만든 친환경재료로서 콘크리트에 혼입되어 미세균열을 제어하는 역할을 한다. 하지만 보강섬유를 혼입한 콘크리트에 대한 연구는 아직도 미비한 실정이고 황토를 혼화재로 사용한 콘크리트의 경우 황토 혼화재의 포졸란 반응과 보강섬유의 보강효과가 복합적으로 나타날 것으로 판단된다. 따라서 본 연구에서는 황토와 PET보강섬유를 혼입한 콘크리트 거동 특성을 분석하기 위하여 건조수축 시험을 통해 황토와 PET보강섬유를 혼입한 콘크리트의 재료특성을 평가하였다.

• Journal of Electrochemical Science and Technology
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• 제2권3호
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• pp.152-156
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• 2011

A hybrid supercapacitor is fabricated using a composite material from $LiMn_2O_4$ (LMO) and activated carbon (AC) as the positive electrode and AC as the negative electrode to form the (LMO + AC)/AC system. Volume ratio (positive : negative) of electrodes is controlled to investigate of the power and energy balance. The (LMO + AC)/AC system shows better performances than the LMO/AC system. Especially, electrochemical impedance spectra, rate charge.discharge and cycle performance testing show that the (LMO + AC)/AC system have an outstanding electrochemical performance at volume ratios of (LMO + AC)/AC = 1 : 1.7 and 1 : 2. Electric double layer capacitor (EDLC) capacitance between AC of the positive electrode and AC of the negative electrode improves power density without loss of capacitance. Stable capacitance is achieved by lowering the positive electrode resistance and balancing the energy and power densities between the positive and negative electrodes by the addition of AC to the positive electrode at high current density.

• 한국실내디자인학회논문집
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• 제23권4호
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• pp.12-22
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• 2014

In this study, the basic information and study design characteristics of the Building Outer Wall Vertical Greening were analyzed. Recorded according to the type of research and analysis, through numerical statistics. Building Outer Wall Vertical Greening design the most appropriate and effective ways to present and try to guidelines. The scope of the research of Building Outer Wall Vertical Greening(2001-2013) was selected the most representative examples. Theory and statistical data analysis and case study research was conducted. The main academic monographs, Library Literature, specializing in design magazines and excerpts from the 28 cases analyzed specifically. Building Outer Wall Vertical Greening should be designed synthetically geographical features of the project, existing material, to consider the value of the building. Architect must be designed depending on accident and comprehensive expertise for architectural design of Building Outer Wall Vertical Greening. Building Outer Wall Vertical Greening requires the professional and comprehensive design approach depending on support of the government and people. However, purpose of use, plant, color, Formative expression, culture, locality, maintenance is properly applied in the design process is not easy.

• Smart Structures and Systems
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• 제17권2호
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• pp.275-296
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• 2016

This paper focuses on developing a new configuration on magnetorheological (MR) brake damper as prosthetic knee. Prosthetic knee uses magnetic fields to vary the viscosity of the MR fluid, and thereby its flexion resistance. Exerted transmissibility torque of the knee greatly depends on the magnetic field intensity in the MR fluid. In this study a rotary damper using MR fluid is addressed in which a single rotary disc will act as a brake while MR fluid is activated by magnetic field in different walking gait. The main objective of this study is to investigate a prosthetic knee with one activating rotary disc to accomplish necessary braking torque in walking gait via T-shaped drum with arc surface boundary and implementing of Newton's equation of motion to derive generated torque at the inner surface of the rotary drum. For this purpose a novel configuration of a T-shaped drum based on the effects of a material deformation process is proposed. In this new design, the T-shaped disc will increase the effective areas of influences in between drum and MR fluid together and the arc wall crushes the particles chains (fibrils) of the MR fluid together instead of breaking them via strain in a conventional MR brake. To verify the proposed MR brake, results of the proposed and conventional MR brakes are compared together and demonstrated that the resisting torque of the proposed MR brake is almost two times greater than that of the conventional brake.

• Journal of Ginseng Research
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• 제36권4호
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• pp.442-448
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• 2012

Somatic embryogenesis is one of good examples of the basic research for plant embryo development as well as an important technique for plant biotechnology such as medicinally important plants. Single embryos develop into normal plantlets with shoots and roots. Therefore, direct single embryogenesis derived from single cells is highly important for normal plant regeneration. Here we demonstrate that the cyclic secondary somatic embryogenesis in Panax ginseng Meyer is a permanent source of embryogenic material that can be used for genetic manipulations. Secondary somatic embryos were originated directly from the primary somatic embryos on hormone-free Murashige and Skoog medium, and proliferated further in a cyclic manner. EM medium (one third of modified MS medium [MS medium containing half amount of NH4NO3 and KNO3] with 2% to 3% sucrose) favored further development of proliferated secondary somatic embryos into plantlets with root system. The plantlets developed into plants with well-developed taproots in half-strength Schenk and Hildebrandt basal medium supplemented with 0.5% activated charcoal.

• 대한화장품학회지
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• 제30권3호
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• pp.307-311
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• 2004

화장품 산업에서 웰빙과 관련하여 inner beauty와 body shaping 상품을 비롯하여 SPA, esthetique, mass-customization, organics, naturals 등에 관련된 상품개발이 연구의 중요한 축을 이룰 것으로 보이며, 웰빙에 대한 고객의 기대로는 건강에 대한 관심과 함께 상품에 대한 안심감, 신뢰성, 윤리성이 우선되어야 할 것이다. 따라서 화장품 영역에서의 웰빙 관련 연구로는 지방 분해, 비타민, 폴리페놀, 오가닉과 함께 항노화에 관련된 체계적인 연구가 이루어져야 할 것이며 아울러 피부과학과 감성 공학을 바탕으로 효능증대, 피부흡수제어, 피부적합성, 제형 및 활성성분안정화, 지속성 증진, 신원료개발이 중요할 것이며, 특히 최근의 바이오 기술. 나노기술. 천연소재기술은 웰빙상품 개발의 초석이라 하겠다.