• Title/Summary/Keyword: Energy absorption

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Electron Spin Resonance (ESR) and Microwave Absorption Studies of Superparamagnetic Iron Oxide Nanoparticles (SPIONs) for Hyperthermia Applications

  • Choi, Yong-Ho;Yi, Terry;Kim, Do-Kyung
    • Journal of the Korean Ceramic Society
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    • v.48 no.6
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    • pp.577-583
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    • 2011
  • Stabilized biocompatible superparamagnetic iron oxide nanoparticles (SPIONs) were prepared by controlled coprecipitation method for hyperthermia application. ESR measurements determined that all of the interactions in the individual SPIONs (1 nm and 11 nm) were antiferromagnetic in nature because the ions contributed to the magnetization with a range of magnetic moments. In-situ monitoring of the temperature increment was performed, showing that the microwave absorption rate of the SPIONs was dispersed in an appropriate host media (polar or non-polar solvents) during microwave irradiation. Microwave absorption energy rates and heat loss of SPIONs in solvent were calculated by non-linear data fitting with an energy balance equation. The microwave absorption rates of SPIONs dispersed in solvent linearly increases when the concentration of SPIONs increases, implying that the microwave absorption rate can be tunable by changing the concentration of SPIONs.

Development for Shock Absorption System by Using FE Analysis (FE 해석을 통한 충격흡수시설의 개발)

  • Kang, Y.H.;Kim, H.J.;Park, D.H.;Kim, K.S.;Kang, B.S.
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.224-229
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    • 2000
  • This paper describe a (mite element computer simulation of a absorption system using full scale car crash test. The full scale test selected for this study is a 80kmh frontal, side and 25% offset impact of a 1993 Ford Taurus vehicle into a absorption system. This absorption system has external rubber and internal steel pannel. This simulation has completed for decision of these components energy absorption performance. Dynamical performance of this system and movement are obtained from this simulation. and then We can appreciate the safety of passenger from measure the vehicle C.G's acceleration.

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Effect of Geometrical Shape and Cold Work on Deformation of the Hydrogen Absorption Metal with Hydrogen Absorption-Desorption Cycling (수소저장-방출싸이클링에 의한 수소저장금속의 변형거동에 관한 형상 및 가공의 영향)

  • Jeong, Y.G.
    • Transactions of the Korean hydrogen and new energy society
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    • v.14 no.3
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    • pp.207-216
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    • 2003
  • By using the electrochemical method, the relation between the deformation and the geometrical shape, and the effect of cold work on hydrogen absorption-desorption cycling in palladium were investigated, In order to study this problem, four kinds of the Pd specimens used were plates and bars as cold worked and annealed states. As results, it is found that the deformation of thickness direction in the palladium plates increased whereas other lateral directions decreased. But the palladium bars showed the same deformation ratio in all directions because of uniform distribution of the $\beta$ phase. Grains in the plate specimens were greatly deformed after hydrogenation cycling whereas grains in the bar specimens were pulverized. Also, deterioration of the hydrogen absorption rate of the bar specimen was larger than the plate specimen. And the effect of cold work on hydrogen absorption capacity was relatively small.

Simulation of Membrane-absorption Hybrid Process for LNG-FPSO (LNG-FPSO용 막-흡수 하이브리드 공정 전산모사)

  • Min, Kwang-Joon;Cho, Habin;Kim, Jin-Kuk;Kang, Sang Wook
    • Membrane Journal
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    • v.28 no.2
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    • pp.90-95
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    • 2018
  • A process design was performed for a removal of acid gases using membrane-absorption hybrid system in LNG-FPSO. Commercial process simulator Promax version 4.0 was utilized for comparing acid gases removal capabilities of amine absorption process and hybrid process. Simulation results show hybrid process could be small amine solvent circulate rate, energy consumption, equipment sizing compared to typical amine absorption process. As a result, hybrid process which is small footprint and energy saving process may be a good solution for the pre-treatment of natural gas in LNG-FPSO.

The Improvement of the Performance of Solar Cooling and Heating Systems (II) - The Characteristics of an Absorption Refrigeration Powered by Solar Systems - (태양열에 의한 냉방 및 난방시스템의 성능향상(II) - 태양열을 이용한 흡수식 냉동기의 성능 -)

  • Park, M.S.;Kim, M.G.;Kim, H.K.;Ro, S.T.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.1 no.1
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    • pp.46-54
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    • 1989
  • The purpose of this study is to obtain the dynamic characteristics of an absorption refrigerator powered by solar energy by experiments. Since the absorption refrigerator power by solar energy should have the characteristics which is suitable for the intermittence and rarity of solar energy, not only the characteristics of the steady state operations but also the partial load and the transient operations should be considered. The minimum available temperature of the storage tank should be known, and the absorption refrigerator can be suitably selected for air-conditioning systems. In this study, the experimental data of the transient state for on-off and warming-up operations has been obtained. Also the experiments are performed which test the minimum available temperature of the storage tank. The results show that it takes 1 hour to get to the steady state of the absorption refrigerator, and the minimum available temperature of the storage tank is about $68^{\circ}C$, and show that in the partial load operations the performance of the absorption refrigerator is improved by applying the modified control method to on-off operations.

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Impact Characteristics on the Laminated Shell for CF/Epoxy Composite (CF/Epoxy 복합재 적층쉘의 충격특성)

  • 양현수;정풍기;김영남;이종선
    • Journal of the Korea Safety Management & Science
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    • v.6 no.1
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    • pp.311-323
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    • 2004
  • This paper is to study the energy absorption characteristics of CF/Epoxy(Carbon Fiber/Epoxy Resin) laminated shell with the various curvatures subjected to transverse impact loadings under the low impact velocity in consideration of design of structural members for use of transportation machine, which are consisted of the characteristics of high stiffness, strength and lightweight. The curvature radius are associated with the energy absorption characteristics of CF/Epoxy laminated shell which is brittleness material. In all tests, maximum load of CF/Epoxy laminated plate is higher than that of laminated shell with curvature, but maximum deflection is lower. And then absorbed energy of laminated shell with curvature is higher than laminated plate(curvature radius is unlimited), As curvature radius is increased, the absorbed energy is increased in laminated shell with curvature.

A study of ballistic impact energy absorbing mechanism of composites (복합재료의 방탄충격에너지 흡수에 관한 연구)

  • 강은영;윤영기;황도인;윤희석
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.773-776
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    • 1997
  • This paper presents an investigation of the energy absorption of composite laminates during ballistic impact. Three components are responsible for the absorption of energy-the tensile failure of fiber, the elastic deformation of the composite, the delamination of composite laminates. The ballistic limit, V/sub 0/, of the laminates is determined using a previous model implemented to determine the energy absorption of the three components listed above. The size of the deformed zone during impact was estimated by an approximate solution for impacts on plates. The carbon/epoxy plates were examined for this research.

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The Study on the Axial Collapse Characteristics of Composite Thin-Walled Members for Vehicles (차체구조용 복합재 박육부재의 축압괴 특성에 관한 연구)

  • 김영남;차천석;양인영
    • Transactions of the Korean Society of Automotive Engineers
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    • v.9 no.6
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    • pp.195-200
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    • 2001
  • Composites have wide applications in aerospace vehicles and automobiles because of the inherent flexibility in their design for improved material properties. Composite tribes in particular, are potential candidates for their use as energy absorbing elements in crashworthiness applications due to their high specific energy absorbing capacity and the stroke efficiency. Their failure mechanism however is highly complicated and rather difficult to analyze. This includes fracture in fibres, in the matrix and in the fibre-matrix interface in tension, compression and shear. The purpose of this study is to investigate the energy absorption characteristics of CFRP(Carbon Fiber Reinforced Plastics) tubes on static and impact tests. Static compression tests have been carried out using the static testing machine and impact tests have been carried out using the vertical crushing testing machine. Interlaminar number affect the energy absorption capability of CFRP tubes. Also, theoretical and experimental have the same value.

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FOA (first-order-analysis) model of an expandable lattice structure for vehicle crash energy absorption of an inflatable morphing body

  • Lee, Dong-Wook;Ma, Zheng-Dong;Kikuchi, Noboru
    • Structural Engineering and Mechanics
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    • v.37 no.6
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    • pp.617-632
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    • 2011
  • A concept of crash energy absorbing (CEA) lattice structure for an inflatable morphing vehicle body (Lee et al. 2008) has been investigated as a method of providing rigidity and energy absorption capability during a vehicular collision (Lee et al. 2007). A modified analytical model for the CEA lattice structure design is described in this paper. The modification of the analytic model was made with a stiffness approach for the elastic region and updated plastic limit analysis with a pure plastic bending deformation concept and amended elongation factors for the plastic region. The proposed CEA structure is composed of a morphing lattice structure with movable thin-walled members for morphing purposes, members that will be locked in designated positions either before or during the crash. What will be described here is how to model the CEA structure analytically based on the energy absorbed by the CEA structure.

Collapse Characteristics of CFRP Hat Shaped Members under the Hygrothermal Environment According to Stacking Angle (열습환경 하에서의 적층각도 변화에 따른 CFRP 모자형 단면부재의 압궤특성)

  • Yang, Yong-Jun;Yang, In-Young;Sim, Jae-Ki
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.18 no.5
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    • pp.507-513
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    • 2009
  • It is important to satisfy the requirements and standards for the protections of passengers in a car accident. There are lots of studies on the crushing energy absorption of structure members in automobiles. We have investigated collapse characteristics and moisture absorption movements of CFRP(Carbon Fiber Reinforced Plastics) hat shaped sectional members when CFRP laminates are under the hygrothermal environment. The absorbed energy, mean collapse load and deformation mode were analyzed for side members which absorbed most of the collision energy. Therefore we have made a static collapse experiment to research into the difference of absorbed energy and deformation mode between moisture absorbed specimen and non-moisture absorbed specimen.

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