• Title/Summary/Keyword: Core composition

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Geochemical characteristics and benthic faunal facies in the sediments around the Oenaro Island, southern part of Korea (외나로도 주변해역 퇴적물의 지화학적 특성과 저서 생물상)

  • Hyun, Sang-Min;Choi, Jin-Woo;Shin, Kyung-Soon;Jang, Man
    • Journal of Environmental Science International
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    • v.11 no.3
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    • pp.215-225
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    • 2002
  • In order to evaluate the relationship between geochemical characteristics and benthic facies of the sediments from the Oenaro Island where red tide proliferation is first observed every year including this year, surface and short multiple core sediment samples were analyzed in terms of geochemical and benthic facies variation. The contents of organic carbon, carbonate, and sulfide gas were relatively low. The variation in C/N ratios, which indicate nature of organic carbon, suggested that the organic carbon recorded in the study area is composed of mixtures of marine and terrigenous organic matters. The concentration of minor elements found at the surface and multiple core sediment samples were also low as well as the enrichment factors(Ef) for the seven heavy metals indicated that the sediment of this area is not polluted significantly. The macrobenthic faunal community comprised 61 species, and their mean density was 708 ind./m2. Polychaete worms were major taxa of this benthic community. A crustacean amphipod, Melita sp. was the most abundant species accounted for 20.7% of total abundance, and the small polychaetes such as Heteromastus filiformis, Paralacydonia poradoxa, Magelona japonica and Sigambra tentaculata were the next dominant species. The macrobenthos around the Oenaro Island were more diverse and abundant than that in Gamak Bay. The benthic communities in the study area sustained somewhat different species composition based on the cluster analysis and the MDS ordination. The benthic community health condition at three stations seemed to be unbalanced, and slightly polluted based on the biological index such as BPI and BC. There was no clear relationship between the geochemistry characteristic and the benthic faunal facies attributed by the micro-algal blooms in this coastal area.

A Study on the Creative Web Design Concept Development (창의적 웹디자인 컨셉 개발에 관한 연구)

  • Seo Mi-Ra;Park Sang-Jin;Kwak Hoon-Sung
    • The Journal of the Korea Contents Association
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    • v.6 no.6
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    • pp.136-143
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    • 2006
  • Contemporary society demands the ability to cope with the change competitively to the designer which is being accelerated of change and various media are emerging. The web design field which is one of the core design industry field of the contemporary society is needing the conversion from manufacturing technology specialization into creative design development composition. Generally, creative design development ability can be learned by studying. So, creativity development education is needed to develop creative design. Creative thought training is perceived as the core condition for competitive design and the education method for this is being proceeded multiply. But the study for design concept is lacking concretely. By this, this paper is to study the model which helps setting the design concept deduction creatively by instigating new ways of thought. The concept development process suggested in the study procedure systemizes the course for creative web design concept deduction and expects it to be utilized in design development to reinforce competitiveness.

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Verification of a novel fuel burnup algorithm in the RAPID code system based on Serpent-2 simulation of the TRIGA Mark II research reactor

  • Anze Pungercic;Valerio Mascolino ;Alireza Haghighat;Luka Snoj
    • Nuclear Engineering and Technology
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    • v.55 no.10
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    • pp.3732-3753
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    • 2023
  • The Real-time Analysis for Particle-transport and In-situ Detection (RAPID) Code System, developed based on the Multi-stage Response-function Transport (MRT) methodology, enables real-time simulation of nuclear systems such as reactor cores, spent nuclear fuel pools and casks, and sub-critical facilities. This paper presents the application of a novel fission matrix-based burnup methodology to the well-characterized JSI TRIGA Mark II research reactor. This methodology allows for calculation of nuclear fuel depletion by combination and interpolation of RAPID's burnup dependent fission matrix (FM) coefficients to take into account core changes due to burnup. The methodology is compared to experimentally validated Serpent-2 Monte Carlo depletion calculations. The results show that the burnup methodology for RAPID (bRAPID) implemented into RAPID is capable of accurately calculating the keff burnup changes of the reactor core as the average discrepancies throughout the whole burnup interval are 37 pcm. Furthermore, capability of accurately describing 3D fission source distribution changes with burnup is demonstrated by having less than 1% relative discrepancies compared to Serpent-2. Good agreement is observed for axially and pin-wise dependent fuel burnup and nuclear fuel nuclide composition as a function of burnup. It is demonstrated that bRAPID accurately describes burnup in areas with high gradients of neutron flux (e.g. vicinity of control rods). Observed discrepancies for some isotopes are explained by analyzing the neutron spectrum. This paper presents a powerful depletion calculation tool that is capable of characterization of spent nuclear fuel on the fly while the reactor is in operation.

Understanding a Core Pilin of the Type IVa Pili of Acidithiobacillus thiooxidans, PilV

  • Araceli Hernandez-Sanchez;Edgar D. Paez-Perez;Elvia Alfaro-Saldana;Vanesa Olivares-Illana;J. Viridiana Garcia-Meza
    • Journal of Microbiology and Biotechnology
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    • v.34 no.3
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    • pp.525-537
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    • 2024
  • Pilins are protein subunits of pili. The pilins of type IV pili (T4P) in pathogenic bacteria are well characterized, but anything is known about the T4P proteins in acidophilic chemolithoautotrophic microorganisms such as the genus Acidithiobacillus. The interest in T4P of A. thiooxidans is because of their possible role in cell recruitment and bacterial aggregation on the surface of minerals during biooxidation of sulfide minerals. In this study we present a successful ad hoc methodology for the heterologous expression and purification of extracellular proteins such as the minor pilin PilV of the T4P of A. thiooxidans, a pilin exposed to extreme conditions of acidity and high oxidation-reduction potentials, and that interact with metal sulfides in an environment rich in dissolved minerals. Once obtained, the model structure of A. thiooxidans PilV revealed the core basic architecture of T4P pilins. Because of the acidophilic condition, we carried out in silico characterization of the protonation status of acidic and basic residues of PilV in order to calculate the ionization state at specific pH values and evaluated their pH stability. Further biophysical characterization was done using UV-visible and fluorescence spectroscopy and the results showed that PilV remains soluble and stable even after exposure to significant changes of pH. PilV has a unique amino acid composition that exhibits acid stability, with significant biotechnology implications such as biooxidation of sulfide minerals. The biophysics profiles of PilV open new paradigms about resilient proteins and stimulate the study of other pilins from extremophiles.

Physical and Mechanical Properties and Fire-endurance Characteristics of Recycled Particleboards

  • Suh, Jin-Suk;Han, Tae-Hyung;Park, Joo-Saeng;Park, Jong-Young
    • Journal of the Korea Furniture Society
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    • v.19 no.6
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    • pp.475-486
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    • 2008
  • In this study, fire-retardant chemicals were melt with mixed composition ratios of dibasic ammonium phosphate and each half of boric acid and borax in hot water, in which hammer-milled chips were immersed to increase swelling of waste particleboards. Also, fire-retardant treated particles from sawn lumber chip and recycled particleboard chip were composed in ratio of 70:30 in core layer to improve boards' properties. Retention ratio of fire-retardant chemicals for the particles for face layer was high due to high specific surface area, and that of sawn lumber chips was somewhat higher than that of recycled particleboard chips. The mixture of particles from sawn lumber chips and recycled PB of 70:30 in weight ratio exceeded bending strength of 100 $kgf/cm^2$. It seemed that the relatively greater portions of dibasic ammonium phosphate affected adversely to dimensional stability, however fire-retardants treatment resulted in distinct effect lowering formaldehyde emission such as $E_0$ type(0.5mg/$\ell$ or less) in KS F 3104. In fire-retardancy, the recycled boards with a mixed ratio of dibasic ammonium phosphate to boric acid borax(50:50 mixture) of 70% to 30% in weight satisfied fire-retardancy 3rd grade in KS F 2271, and also this composition from cone calorimeter test met same standard grade figuring total heat release of 4.6MJ/$m^2$.

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Preparation and Performance Improvement of Polylactic acid based composites by stereocomplex (스테레오 컴플렉스를 이용한 폴리유산 복합재 제조 및 성능 개선)

  • Hong, Chae-Hwan;Kim, Yeon-Hee;Park, Jun-Seo;Nam, Byeong-Uk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.3
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    • pp.1671-1676
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    • 2015
  • A unique crystallization behavior of poly(L-lactide)(PLLA)/poly(D-lactide)(PDLA) stereocomplex(SC) was observed when a PLLA/PDLA blend was subjected to the specific melting conditions. Therefore, we tried to blend PLLA and PDLA at overall composition to form PLA stereocomplexes. Moreover, impact modifier and reinforcement materials such as talc and glass fiber added to enhance the mechanical and thermal properties such as impact strength and heat distortion temperature(HDT). As a result, we got one representative result, one composite recipe with HDT $115^{\circ}C$. For more economic technology, we tried to blend PLLA and Polypropylene at overall composition and we got another representative result which could be applied to current PP/talc composites and ABS materials. The core technology of this might be the well dispersion of glass fibers into the matrix resin such as PP, PLLA and impact strength modifier.

A Study on the Symbolic Meaning of Traditional Wedding Costume Inherent in the Afterlife Wedding Kut in the Honam Area - Focusing on the Process Performing A Traditional Wedding Ceremony- (호남지역 저승 혼사굿에 내재된 전통복식의 상징적 의미 - 혼례의식 연행과정을 중심으로-)

  • Kim, Eun-Jung
    • Journal of the Korean Society of Costume
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    • v.62 no.8
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    • pp.71-80
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    • 2012
  • The Kut is the core of the traditional folk religion. The afterlife wedding Kut actually performs a traditional wedding ceremony by personifying the deceased in the process of performing the composition of Kut geori that cannot be observed from other Kuts, which is an important means to convey the situation of Kut more clearly. A traditional wedding ceremony performed in the Kut enables the audience to understand the meaning behind the Kut. The costume worn in the traditional wedding ceremony of the afterlife wedding Kut makes the audience understand the existence of the deceased by the use of a scarecrow dialect and makes them feel a vivid sense of the scene emitting from the Kut, which performs a traditional wedding ceremony in the composition of Kut geori. The results of this study showed that a shaman who led the afterlife wedding Kut had a scarecrow that symbolized the bride and a bridegroom wear the traditional wedding costume in order to visualize the deceased and express the symbol of a wedding which could not be made in this world. It can be interpreted that the traditional costume derived from the afterlife wedding Kut plays a symbolic role, which converts the deceased into a living person through the formal aspect of ceremonial costume and the cultural aspect of wedding ceremony.

A Study on the Exhibition Method to Enhance the Visitors' Understanding Contents - Focus on the Domestic Dam Exhibition Centers - (콘텐츠 이해도 강화를 위한 전시방식에 관한 연구 - 국내 댐 전시관을 중심으로 -)

  • Yi, Joo-Hyoung
    • Korean Institute of Interior Design Journal
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    • v.19 no.3
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    • pp.196-204
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    • 2010
  • Human beings are having suffered from the unexpected climate changes which are caused by global warming leaded from air pollution. More than 3 billions of people will be forced to experience insufficient water in 2015. In Korea, over 70% of precipitation has been concentrating in Summer season. Furthermore, natural disasters has been occurred constantly all over the country. The unusual flood and drought have broken out not only victims but also, property damages. By the natural condition, the effective consuming and controlling system of water is going to be the core business field and constructing dams will be encouraged and promoted for the system. To convince the objectionable against the constructing dams, a dam exhibition center stands the very important position by being responsible for the presenting positive factors and highlighting the beneficial functions. The dam exhibition center is built as complex space combined by information center regarding water resources and visitor center for the community nearby the inundated area. Combined of the different purposes, the dam exhibition center can be confused to understand the concept and contents established in the space. To enhance the visitors' understanding contents of the dam exhibition center, the spatial composition and contents are being analyzed with existing centers and define the most effective exhibition methods between the spaces and visitors. This study will be the basic quantitative analysis data for the following design works those can get the better insight how to make visitors to get information and agreement of constructing dams effectively.

Magnetic Properties of (Fe, Co)-Al-B-Nb Nanocrystalline Alloys on Composition and Annealing Temperature ((Fe, Co)-Al-B-Nb 초미세결정립합금의 조성 및 열처리온도에 대한 자기적 특성변화)

  • 강대병;김택기;조용수
    • Journal of the Korean Magnetics Society
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    • v.5 no.1
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    • pp.1-7
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    • 1995
  • ${(Fe_{0.85}Co_{0.15})}_{75}Al_{7}B_{18-x}Nb_{x}(x=2,\;4\;and\;6\;at%)\;and\;{(Fe_{0.85}Co_{0.15})}_{75}Al_{y}B_{21-y}Nb_{4}(y=3,\;5,\;7,\;9\;at%)$ alloys were prepared by a single-roll quenching method. Microstructure and magnetic properties of the alloys such as saturation magnetization, initial permeability, coercive force and power loss have been investigated as functions of composition and armea1ing temperature. Nanocrystallines are obtained by armealing of as-prepared amorphous alloys in all compositions except the alloy of 9 at% AI. Saturation magnetization increases after armea1ing and, decreases with Nb content. However, AI and B affects the saturation magnetization insignificantly. Initial perrreability of nanocrystallized alloy at 50 kHz is improved roore than twice compared to that of the as-prepared alloy. Coercive force and core loss reach less than half after armea1ing.

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The Electrical Properties of High Voltage Mutilayer Chip Capacitor with X7R by addition of Er2O3 and Glass Frit (고압용 X7R 적층 칩 캐패시터의 Er2O3 및 유리프릿 첨가에 따른 전기적 특성)

  • Yoon, Jung-Rag;Kim, Min-Kee;Chung, Tae-Seog;Woo, Byoung-Chul;Lee, Seog-Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.5
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    • pp.440-446
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    • 2008
  • To manufacture the MLCC with X7R for high voltage stability, $BaTiO_3-MgO-MnO_2-Y_2O_3$ with $(Ba_{0.4}Ca_{0.6})SiO_3$ glass frit was formulated. Based on this composition, the addition of $Er_2O_3$ showed that TCC(Temperature Coefficient Capacitance) at $85^{\circ}C$ was improved from 5 % to ${\sim}0\;%$, but the dielectric constant and IR (Insulation Resistance) were decreased. The glass frit improved the dielectric constant and IR, so the appropriate contents of $Er_2O_3$ and glass frit were 0.6 mol% and 1 wt%, respectively. It showed that the dielectric constant and RC constant were 2,550 and 2,000 (${\Omega}F$), respectively in the sintering condition at $1250^{\circ}C$ in PO2 $10^{-7}$ Mpa. The MLCC with $3.2{\times}1.6$ (mm) size and $1\;{\mu}F$ was also suited for X7R with the above composition.