• 제목/요약/키워드: (r,s)-components

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Understanding G.A.R.L.I.C.s.: An Innopreneurship Platform for Smart Cities

  • Narasimhalu, Arcot Desai
    • World Technopolis Review
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    • 제8권1호
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    • pp.8-20
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    • 2019
  • The intent of this paper is to identify key actors of a sustainable Smart City and define metrics that will allow assessment and better management of Sustainable Smart Cities. The paper is organized in two major segments. The first segment reviews the definition, six components, six action items of Smart Cities. It describes briefly a sample Smart City project and presents a selection of different dimensions along which Smart Cities are ranked and the rankings. The segment also discusses the technology architecture of a Smart City and then examines the definition and components of an innovation platform. The second presents the original contributions of the paper. It first introduces the dynamics created seven key actors of a Smart City ecosystem and describes their existing and potential contributions. It then defines Innopreneurship platform and presents a triple bottom line based quality metric to evaluate such a platform. This segment also discusses reengineering an economy and suggests a Smart City's Innovation Platform Score. The actions to be taken by the key actors of a Smart City in order to make it a Sustainable Smart City are described in several subsections. We hope these concepts and metrics will be a good starting point and will be refined over time by others.

Effect of test-caused degradation on the unavailability of standby safety components

  • S. Parsaei;A. Pirouzmand;M.R. Nematollahi;A. Ahmadi;K. Hadad
    • Nuclear Engineering and Technology
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    • 제56권2호
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    • pp.526-535
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    • 2024
  • This paper proposes a safety-critical standby component unavailability model that contains aging effects caused by the elapsed time from installation, component degradation due to surveillance tests, and imperfect maintenance actions. An application of the model to a Motor-Operated Valve and a Motor-Driven Pump involved in the HPIS of a VVER/1000-V446 nuclear power plant is demonstrated and compared with other existing models at component and system levels. In addition, the effects of different unavailability models are reflected in the NPP's risk criterion, i.e., core damage frequency, over five maintenance periods. The results show that, compared with other models that do not simultaneously consider the full effects of degradation and maintenance impacts, the proposed model realistically evaluates the unavailabilities of the safety-related components and the involved systems as a plant age function. Therefore, it can effectively reflect the age-dependent CDF impact of a given testing and maintenance policy in a specified time horizon.

A COMPREHENSIVE VIEW OF LARGE-SCALE MAGNETIC FIELDS, WITH EMPHASIS ON THE GALACTIC MAGNETIC FIELD NEAR THE SUN

  • HEILES CARL
    • 천문학회지
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    • 제29권spc1호
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    • pp.151-154
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    • 1996
  • We examine the observations of large-scale magnetic fields in the Universe. We begin at the largest scale with clusters of galaxies and work our way down through galaxies and finally to the Milky Way. on which we concentrate in detail. We examine the observations of the Galactic magnetic field, and their interpretation, under the philosophy that the Galactic magnetic field is like that in other spiral galaxies. We use pulsar data. diffuse Galactic synchrotron emission, and starlight polarization data to discuss the Galaxy's global magnetic configuration and the uniform ($B_u$), random ($B_r$), and total ($B_t$) components of the field strength. We find disagreement among conclusions derived from the various data sets and argue that the pulsar data are not the best indicator for large-scale Galactic field. Near the Solar circle, we find that the azimuthal average of $B_t$ is 4.2$\mu$G and we adopt $B_u\~$2.2 and $B_r\~3.6{\mu}G$. $B_t$ is higher in spiral arms, reaching $\~5.9{\mu}G$. $B_t$ is higher for smaller $R_{Gal}$, reaching $\~8.0{\mu}G$ for $R_{Gal}$ = 4.0 kpc. The pattern of field lines is not concentric circles but spirals. The inclination of the magnetic spiral may be smaller than that of the Galaxy's spiral arms if our sample, which refers primarily to the interarm region near the Sun, is representative. However, it is not inconceivable that the local field lines follow the Galaxy's spiral pattern, as is observed in external galaxies.

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Isolation and Characterization of Bioactive Compounds from Root of Rubus coreanus Miquel and their Antimicrobial Activity

  • Jang, Ha Na;Ha, Ji Hoon;Lee, Yoon Ju;Fu, Min Min;Park, Soo Nam
    • 한국미생물·생명공학회지
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    • 제47권1호
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    • pp.54-63
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    • 2019
  • Rubus coreanus Miquel (RCM), also known as Korean blackberry or bokbunja, is used as a South Korean traditional medicine to treat acne and inflammatory skin conditions. The antimicrobial activity of RCM root and its active compounds remain unclear. In this study, we prepared a 50% ethanol fraction, ethyl acetate fraction, and acid-treated ethyl acetate fraction (aglycone fraction) of RCM root, and evaluated antibacterial activities against the skin pathogens Staphylococcus aureus, Pseudomonas acnes, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. In a paper disc assay, all fractions of RCM root showed antimicrobial activities against the five skin pathogens. The ethyl acetate fraction displayed 6-, 12-, and 2-fold higher minimal inhibitory concentration (MIC) than the 50% ethanol fraction against S. aureus, E. coli, and P. acnes, respectively. The aglycone fraction displayed 2-fold higher MIC than methyl paraben against P. acnes, S. aureus, E. coli, and P. aeruginosa. The ethyl acetate fraction displayed a minimal bactericidal concentration (MBC) similar to that of methyl paraben, and the aglycone fraction showed 2- to 4-fold higher MBCs than those of methyl paraben. In particular, the ethyl acetate fraction was not cytotoxic and showed thermal stability after incubation at high temperatures ($60-121^{\circ}C$). Finally, the ethyl acetate fraction was separated and four components were identified: procyanidin C, propelagonidin dimer, ellagic acid, and methyl ellagic acid acetyl pentose. The compounds showed high antibacterial activities. These results suggest that RCM root is potentially applicable as a natural preservative in cosmetics.

삼백초 추출물의 3T3-L1 세포에 대한 지방축적 억제효과 (Inhibition of Adipogenesis in 3T3-L1 Adipocytes with Ethanol Extracts of Saururus chinensis)

  • 신옥수;신연호;이강혁;김건용;김기호;박정극;안재일;송계용
    • KSBB Journal
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    • 제27권6호
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    • pp.381-386
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    • 2012
  • Obesity increases the risk of many adult diseases, such as atherosclerosis, diabetes, hypertension, ischemic heart disease and breast cancer. Inhibition of adipogenesis is an effective way in the anti-obesity management. Because of main components of Saururus chinensis is flavonoid, it has been showed some improvement by its antioxidant effects on the atherosclerosis, heart disease and diabetic hyperlipidemia. But mechanism of anti-obesity effect of S. chinensis is not clear. We investigated the effects of ethanol extracts of S. chinensis on adipogenesis in the 3T3-L1 pre-adipocyte. The 3T3-L1 cell line is commonly used to study adipogenesis in vitro. In this study, ethanol extracts of S. chinensis significantly decrease the lipid accumulation in the 3T3-L1 cells proved by measuring triglyceride contents and Oil red O staining. The proposed mechanism of inhibition of adipogenesis in the 3T3-L1 cells with ethanol extracts of S. chinensis is down-regulation of transcriptional factors and adipocyte-specific genes such CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$) and Peroxisome proliferator activated receptor ${\gamma}$ ($PPAR{\gamma}$) in concentration dependent pattern. These results suggest that ethanol extracts of S. chinensis inhibits adipognesis in the 3T3-L1 cells and can be used as a safe and efficient natural substance to manage anti-obesity.

S-Octree: An Extension to Spherical Coordinates

  • Park, Tae-Jung;Lee, Sung-Ho;Kim, Chang-Hun
    • 한국멀티미디어학회논문지
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    • 제13권12호
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    • pp.1748-1759
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    • 2010
  • We extend the octree subdivision process from Cartesian coordinates to spherical coordinates to develop more efficient space-partitioning structure for surface models. As an application of the proposed structure, we apply the octree subdivision in spherical coordinates ("S-Octree") to geometry compression in progressive mesh coding. Most previous researches on geometry-driven progressive mesh compression are devoted to improve predictability of geometry information. Unlike this, we focus on the efficient information storage for the space-partitioning structure. By eliminating void space at initial stage and aligning the R axis for the important components in geometry information, the S-Octree improves the efficiency in geometry information coding. Several meshes are tested in the progressive mesh coding based on the S-Octree and the results for performance parameters are presented.

20(S)-ginsenoside Rg3 inhibits glycoprotein IIb/IIIa activation in human platelets

  • Kwon, Hyuk-Woo
    • Journal of Applied Biological Chemistry
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    • 제61권3호
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    • pp.257-265
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    • 2018
  • The Panax ginseng Mayer is used in conventional medicine in Asia owing to its preventing effects on thrombosis, hypertension, atherosclerosis, vasorelaxation and myocardial infarction. Because platelets are crucial mediators of cardiovascular diseases, many studies have investigated its functions. The previous study showed the antiplatelet effects of crude ginseng fraction and two of its components, ginsenoside Rg3 (20S and 20R). In addition, ginsenoside Rg3-enriched fraction shows an inhibitory effect on collagen-activated rat platelets. However, the mechanism underlying this effect remains unclear. Thus, I investigated the inhibitory action of ginsenoside Rg3 (20S, G-Rg3) on the regulation of signaling molecules involved in ${\alpha}IIb/{\beta}_3$ activation. I found that G-Rg3, in a cyclic AMP dependent manner, inhibited thrombin-induced activation of human platelets and affinity of fibrinogen and fibronectin with ${\alpha}IIb/{\beta}_3$. Thus, in the present study, G-Rg3 showed an inhibitory effect on glycoprotein IIb/IIIa (${\alpha}IIb/{\beta}_3$) activation, suggesting its potential use for preventing platelet-mediated thrombotic disease.

금속소재의 고변형률 영역 유동응력선도 평가 (Evaluation of Flow Stress of Metal up to High Strain)

  • 이상곤;이인규;이성윤;이성민;정명식
    • 소성∙가공
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    • 제29권6호
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    • pp.316-322
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    • 2020
  • The flow stress curve is usually determined via uniaxial tensile or simple compression test. However, the flow stress curve up to high strain cannot be obtained using these two tests. This study presents a simple method for obtaining the flow stress curve up to high strain via FE analysis, a simple compression test, and an indentation test. In order to draw the flow stress curve up to high strain, the indentation test was carried out with the pre-stained specimen using the simple compression test. The flow stress curve of Al6110 was evaluated up to high strain using the proposed method, and the result was compared with the flow stress curve of the uniaxial tensile test of the initial material.

Degradation properties of phytin from soybean and rice bran by phytases produced from Aspergillus sp. 5990

  • J. S. Yang;H. J. Suh;H. S. Kang;T. S. Shin;D. S. Byun;Kim, H. R.
    • 한국어업기술학회:학술대회논문집
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    • 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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    • pp.220-221
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    • 2001
  • Phytic acid (myo-inositol 1,2,3,4,5,6-hexakisdihydrogen phosphate) is one of the major storage form of phosphorous in the seeds of plants, which are the principal components of feed stuffs. Monogastric animals like Pigs and poultry as well as fish lack phytase activities in their digestive system and most undigested phytic acid was excreted in their manure. (omitted)

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생명현상 관찰에서 나타나는 인과적 의문 생성의 ERF 특성 : MEG 연구 (ERF Components Patterns of Causal Question Generation during Observation of Biological Phenomena : A MEG Study)

  • 권석원;권용주
    • 과학교육연구지
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    • 제33권2호
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    • pp.336-345
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    • 2009
  • 이 연구의 목적은 생명현상 관찰에서 나타나는 인과적 의문 생성 ERF components를 개발하는 것이다. 이를 위해 우선 인지심리적 방법으로 생명현상 기반의 인과적 의문생성 유발 사진 과제를 개발하였다. 이를 활용해 전기생리적 방법인 MEG(Magnetoencephalography) 두뇌 영상 기기를 이용하여 시계열적 두뇌 처리과정에 기초한 인과적 의문의 ERF(Event Related Fields) 패턴을 확인할 수 있었다. 생명현상 기반의 인과적 의문생성 유발 사진은 과학교육 전문가와 과학교육연구진으로 구성된 인원의 R&D 방식으로 개발되었다. 과제는 생물군 유형에 따라 동물(A, animal), 미생물(M, microbe), 식물(P, plant)과제로 분류 형태를 나누고, 생물 개체 수준의 유형에 따라 개체간 상호작용(i, interaction), 단일 개체(a, all), 개체 일부(p, part)로 구분하여 총 100장에 대한 인과적 의문 유발 사진을 완성하였다. 이후 서울대학병원 MEG 센터팀과의 세미나 과정을 통해 MEG 과제용 패러다임을 개발하고, 과학교육 전공 여자 대학원생 5명(M=26.4, SD=2.30)을 대상으로 인과적 의문생성간 MEG data를 수집하였다. 이를 통해 인과적 의문 유형별 고유 특성을 확인하기 위해 MEG ERF components 분석을 실시하였다. 인과적 의문 생성시 나타나는 ERF components 분석 결과 M1(100~130ms), M2(220~280ms), M3(320~390ms), M4(460~520ms) 총 4개 components 패턴이 발견되었다. M1과 M2의 경우 인과적 의문 사진 과제 제시에 따라 피험자가 관찰하는 동안 보고 되는 것으로 dipole fitting 과정을 통해 두뇌 활성 영역을 확인해 본 것처럼 시각령이 위치하는 후두엽에 걸쳐 확인되었다. M3 components의 경우 인과적 의문에 대한 불확실감을 해소하기 위해 장기기억 저장소로부터 경험 상황을 가지고 오는 귀추의 과정을 반영한다고 볼 수 있다. 이는 이전 경험상황을 분석하는 단계에 해당하며 학생들이 가설을 생성할 때 가장 큰 어려움을 경험하여 교사의 적절한 도움이 요구되는 부분이다. M4 components는 장기 기억 속의 경험 상황에서 인과적 의문에 대한 설명자를 표상하는 단계에 해당하는 것으로 인과적 의문 생성 후 가설을 만드는 전 단계에 해당 한다고 할 수 있다. 본 연구는 확인된 인과적 의문 생성시 나타나는 MEG ERF components와 latency 시간을 통해 인과적 의문 생성에 어려움을 호소하는 학생들에 대한 개별적 교수 처치와 더불어 고등인지 영역의 ERF 연구의 기초를 마련하였다는데 의의가 있다고 하겠다.

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