• Title/Summary/Keyword: 에너지 정의

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Prediction of Shelf-life of Instant Noodle by Hexanal Content (헥사날에 의한 라면의 저장성 예측)

  • Kim, Bok-Soon;Kim, Sung-Kon
    • Korean Journal of Food Science and Technology
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    • v.26 no.3
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    • pp.331-335
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    • 1994
  • The shelf-life of instant noodle stored at $35{\sim}65^{\circ}C$ under dark condition was estimated from the change of hexanal content, which was linearly increased as the storage time increased. The rate constants of hexanal production at various storage temperatures followed Arrhenius relationship. The activation energy and $Q_{10}$ calculated were 12.7 kcal/mole and 1.92, respectively. The rancid flavor was organoleptically detected after 6 days at $65^{\circ}C$ and 13 days $50^{\circ}C$, at which the content of hexanal was 3.5 ppm. The shelf-life of instant noddle at $21^{\circ}C$ based on $Q_{10}$ value of hexanal production was about 110 days. The changes of acid value and peroxide value of instant noodle during storage followed similar pattern to those of hexanal. The activation energy and $Q_{10}$ for both acid value and peroxide value were 16.0 kcal/mole and 2.55, respectively. The hexanal content showed a high positive correlation with acid value as well as peroxide value at all storage temperatures.

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Evaluation of Native Soybean Collection for Resistance to Purple Blotch (수집재래종대두의 자주빛무늬병(Cercospora kikuchii)에 대한 저항성검정)

  • Oh Jeung Haing;Kwon Shin Han
    • Korean journal of applied entomology
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    • v.20 no.3 s.48
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    • pp.131-134
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    • 1981
  • Native soybean collections were evaluated to search a resistant gene source to purple blotch caused by Cercospora kikuchii. Among 467 native lines, about $28.9\%$ of the lines was less than $0.1\%$ and $13.4\%$ was over $2\%$ in natural infection of purple blotch. Natural infection seemed to be significantly associated with weather conditions at the early podding stage. A significant correlation between natural infection and purple discoloration by seed inoculation was observed and this method seemed to be effective as a preliminary screening technique for resistance to purple blotch. Most of the late maturing native soybeans showed susceptible reaction by the seed inoculation contrary to low infection under natural conditions, indicating that the low natural infection might be due to disease escaping by the late maturing instead of their genetic resistance.

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Development of Green Building Certification Framework for Urban Neighborhood Scale Development (근린단위 녹색건축인증 평가체계 개발)

  • Jung, Seunghyun
    • The Journal of the Korea Contents Association
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    • v.19 no.12
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    • pp.203-214
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    • 2019
  • Green building certification is being implemented in various countries around the world for the purpose of securing sustainability and reducing energy use and carbon emissions. Korea has been implementing G-SEED, a green building certification, for buildings since 2002, but in foreign countries, the evaluation target has been expanded from buildings to neighborhood units, cities, and infrastructure. Therefore, the purpose of this study was to establish Korean green building certification system in terms of neighborhood scale. In order to make Korean certification scheme for neighborhood communities, three major international certification systems (BREEAM Communities, LEED-ND, and CASBEE-UD) were compared. Comparison was executed about definitions and goals, certification system and range, certification categories, and regulation relationship by literature review. Based on the results, the evaluation system proposal including the scope, subjects, and items for green building certification in Korea was proposed.

Development and Application of Carbon Emissions Estimation Methodology During the Life Cycle of Road (도로의 전과정 탄소배출량 산정방법 개발 및 적용)

  • Kwak, In-Ho;Park, Kwang-Ho;Hwang, Young-Woo;Park, Ji-Hyoung
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.6
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    • pp.382-390
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    • 2012
  • Global warming has been hot issue world wide. Korea has been dealing with the global issue under the slogan of low carbon and green-growth such as setting national greenhouse gas (GHG) reduction targets and allocation to each industrial sector. Infrastructure construction, in which enormous social overhead capital (SOC) is input, has great role as one of the actions. Road is one of the representative infrastructure and large amount of resources is utilized in its construction, operation and maintenance stage. The estimation methodology of life cycle carbon emissions was developed and applied to a case study of highway currently under construction in this study. Also, total carbon emissions of all the highway in South Korea at present (2009) and cumulative carbon emissions from 2009 to 2020 were estimated using the results of case study.

A Fundamental Study for the Behavior of Lightweight Aggregate Concrete Slab Reinforced with GFRP Bar (GFRP bar를 휨보강근으로 사용한 경량골재콘크리트 슬래브의 거동에 관한 기초적 연구)

  • Jeon, Sang Hun;Shon, Byung Lak;Kim, Chung Ho;Jang, Heui Suk
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.3
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    • pp.99-108
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    • 2012
  • In this paper, to intend anticorrosive effect and weight reduction of conventional reinforced concrete slab, lightweight concrete slab reinforced with glass fiber reinforced polymer(GFRP) bar was considered and some basic behaviour of the slab were investigated. Measurement of splitting tensile strength and fracture energy of the concrete, a number of flexural experiment of the slab, numerical analysis using nonlinear finite element analysis, and comparison of the experimental results to the numerical analysis, were conducted. As a result, even the weight of the lightweight concrete slab could be reduced by about 28% than the normal concrete slab, failure load of the lightweight concrete slab was 36% smaller than the normal concrete slab. Such a thing can be attributed to the lower axial stiffness and lower bond strength of GFRP bar. In the numerical analysis, to consider decreasing property of bond strength of the lightweight concrete, interface element was used between the concrete and the GFRP bar elements and this method was shown to be a better way for the numerical analysis to approach the experimental results.

Changes in Volume of Soybeans during Hydration (콩의 침지중 부피의 변화)

  • Kim, Jong-Goon;Kim, Woo-Jung;Kim, Sung-Kon
    • Korean Journal of Food Science and Technology
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    • v.21 no.2
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    • pp.289-293
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    • 1989
  • During soaking of soybeans in water at $4^{\circ}C{\sim}98^{\circ}C$, the volume gain of soybeans held a linear relation with the square root of soaking time regardless of soaking temperatures and showed a highly positive correlation with weight gain, which indicated that the volume increase of soybeans was basically due to the diffusion of water. The activation energies for the volume increase were changed at $40^{\circ}C$. The log time to reach a fixed moisture content showed a linear relation with the soaking temperature during soaking of soybeans at $4^{\circ}C-60^{\circ}C$. The z-value to reach 50% hydration was $50^{\circ}C-55^{\circ}C$.

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Development of Monte Carlo Simulation Code for the Dose Calculation of the Stereotactic Radiosurgery (뇌 정위 방사선수술의 선량 계산을 위한 몬테카를로 시뮬레이션 코드 개발)

  • Kang, Jeongku;Lee, Dong Joon
    • Progress in Medical Physics
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    • v.23 no.4
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    • pp.303-308
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    • 2012
  • The Geant4 based Monte Carlo code for the application of stereotactic radiosurgery was developed. The probability density function and cumulative density function to determine the incident photon energy were calculated from pre-calculated energy spectrum for the linac by multiplying the weighting factors corresponding to the energy bins. The messenger class to transfer the various MLC fields generated by the planning system was used. The rotation matrix of rotateX and rotateY were used for simulating gantry and table rotation respectively. We construct accelerator world and phantom world in the main world coordinate to rotate accelerator and phantom world independently. We used dicomHandler class object to convert from the dicom binary file to the text file which contains the matrix number, pixel size, pixel's HU, bit size, padding value and high bits order. We reconstruct this class object to work fine. We also reconstruct the PrimaryGeneratorAction class to speed up the calculation time. because of the huge calculation time we discard search process of the ThitsMap and used direct access method from the first to the last element to produce the result files.

Temperature and stress dependence of prism plane slip dislocation velocity in sapphire ($\alpha$-Al$_2$O$_3$) single crystals (사파이어($\alpha$-Al$_2$O$_3$) 단결성에 있어 prism plane slip 전위속도의 온도 및 응력의존성)

  • 윤석영;이종영
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.10 no.4
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    • pp.337-343
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    • 2000
  • Prism plane slip {11$\bar{2}$0}1/3{$\bar{1}$120} location velocity in sapphire ($\alpha$-Al$_2$O$_3$) single crystals was measured by etch-pit method. The dislocation velocities were measured as a function of temperature and stress between $1150^{\circ}C$ and $1400^{\circ}C$ for engineering stresses in the range 140 to 250 MPa. The dependence of temperature and stress in dislocation velocity was investigated. The activation energy for dislocation velocity was determined to be 4.2$\pm$0.4 eV. On the other hand, the stress exponent (m) describing the stress dependence of dislocation velocities was in the range of 4.5$\pm$0.8. Through this experiments, it was reconfirmed that the basal plane in sapphire single crystals has the 3-fold symmetry.

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Properties of SBR Nanocomposites Reinforced with Organoclay/Carbon Black Dual Phase Fillers (카본 블랙/유기화 클레이로 보강된 SBR 나노 복합재료: 모폴로지와 기계적 물성)

  • Kang, B.S.;Kim, W.
    • Elastomers and Composites
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    • v.42 no.1
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    • pp.9-19
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    • 2007
  • In this study, SBR (Styrene-butadiene rubber: solid content: 25 wt%) nanocomposites reinforced with carbon/organoclay(C18-MMT) were manufactured by a latex method. The SBR nanocomposites was made with the dual phase fillers. The mixing ratios, i.e. carbon black/C18-MMT, were 50/0, 49/1, 48/2, 47/3, 45/5, 44/6, 40/10. Total filler content of compounds was restricted to 50 phr. Cure characteristics and mechanical properties of SBR nanocomposites with carbon black and C18-MMT were evaluated. The SBR nanocomposites containing 49/1 ratio of carbon black/C18-MMT showed good dispersity and excellent values of ODR torque, tensile strength, modulus and tear energy. It was found that the improvement of the mechanical properties was mainly due to the reinforcing effect, i.e., the improvement of dispersion of silicates in the rubber matrix.

Effect of Freezing on Hydration Rate and Sprouting Characteristics of Soybeans (대두의 수화속도와 콩나물의 발아특성에 대한 동결처리 효과)

  • Rhim, Jong-Whan;Oh, Bong-Yun;Kim, Dong-Han;Ham, Kyung-Sik
    • Korean Journal of Food Science and Technology
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    • v.35 no.4
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    • pp.660-665
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    • 2003
  • Effect of freezing on the hydration rate and growth characteristics of bean sprout of two domestic cultivars of soybean, Eunha beans and Taegwang beans, was investigated. Freezing of the soybeans at $-80^{\circ}C$ affected characteristics of the hydration and growth of soybean sprout of the beans. Hydration rate of the frozen beans depended on the hydration temperature. It decreased up to 50% at lower than $60^{\circ}C$ of hydration temperature, but it did not decrease at higher than $60^{\circ}C$. Activation energies of frozen Eunha and Taegwang beans were 39.79 and 39.25 kJ/mol, respectively. Kinetic compensation effect between activation energy values and the pre-exponential factor for the hydration of soybeans with or without freezing was observed. Germination rate and thickness of the bean sprout increased by freezing, however, yield and weight were not affected by freezing.