• 제목/요약/키워드: f-factor

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ON π𝔉-EMBEDDED SUBGROUPS OF FINITE GROUPS

  • Guo, Wenbin;Yu, Haifeng;Zhang, Li
    • 대한수학회보
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    • 제53권1호
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    • pp.91-102
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    • 2016
  • A chief factor H/K of G is called F-central in G provided $(H/K){\rtimes}(G/C_G(H/K)){\in}{\mathfrak{F}}$. A normal subgroup N of G is said to be ${\pi}{\mathfrak{F}}$-hypercentral in G if either N = 1 or $N{\neq}1$ and every chief factor of G below N of order divisible by at least one prime in ${\pi}$ is $\mathfrak{F}$-central in G. The symbol $Z_{{\pi}{\mathfrak{F}}}(G)$ denotes the ${\pi}{\mathfrak{F}}$-hypercentre of G, that is, the product of all the normal ${\pi}{\mathfrak{F}}$-hypercentral subgroups of G. We say that a subgroup H of G is ${\pi}{\mathfrak{F}}$-embedded in G if there exists a normal subgroup T of G such that HT is s-quasinormal in G and $(H{\cap}T)H_G/H_G{\leq}Z_{{\pi}{\mathfrak{F}}}(G/H_G)$, where $H_G$ is the maximal normal subgroup of G contained in H. In this paper, we use the ${\pi}{\mathfrak{F}}$-embedded subgroups to determine the structures of finite groups. In particular, we give some new characterizations of p-nilpotency and supersolvability of a group.

지중케이블 변전소의 고장전류 분류율과 접지전위상승 특성 (Characteristics of Fault Current Division Factor & Groud Potential Rise of a Substation fed exclusively by Power Cables)

  • 최종기;정길조;김선구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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    • pp.295-297
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    • 1998
  • This paper shows characteristics of fault current division factor $S_f$, which is a ratio of earth- return current to total fault current, at a substation fed exclusively by power cables under unsymmetrical fault condition, such as single line-to-ground fault. In substation grounding system design, $S_f$ is a very important factor determining GPR, touch and step voltage at a substation under fault condition. In case of substations fed by overhead lines, 40-60% of $S_f$ has been typically used, although it is a very conservative value with no other network conditions considered. It is authors' hope that $S_f$ presented in this paper could hopefully be a basic reference in designing of substation grounding system, especially for a substation fed exclusively by power cables.

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The novel peptide F29 facilitates the DNA-binding ability of hypoxia-inducible factor-1α

  • Choi, Su-Mi;Park, Hyun-Sung
    • BMB Reports
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    • 제42권11호
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    • pp.737-742
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    • 2009
  • Hypoxia-inducible factor-$1{\alpha}/{\beta}$ (HIF-$1{\alpha}/{\beta}$) is a heterodimeric transcriptional activator that mediates gene expression in response to hypoxia. HIF-$1{\alpha}$ has been noted as an effective therapeutic target for ischemic diseases such as myocardiac infarction, stroke and cancer. By using a yeast two-hybrid system and a random peptide library, we found a 16-mer peptide named F29 that directly interacts with the bHLH-PAS domain of HIF-$1{\alpha}$. We found that F29 facilitates the interaction of the HIF-$1{\alpha/\beta}$ heterodimer with its target DNA sequence, hypoxia-responsive element (HRE). The transient transfection of an F29-expressing plasmid increases the expression of both an HRE-driven luciferase gene and the endogenous HIF-1 target gene, vascular endothelial growth factor (VEGF). Taken together, we conclude that F29 increases the DNA-binding ability of HIF-$1{\alpha}$, leading to increased expression of its target gene VEGF. Our results suggest that F29 can be a lead compound that directly targets HIF-$1{\alpha}$ and increases its activity.

Correlation Equation for Retention Factor and Resolution of Ibuprofen in SFC

  • Han, Soon-Koo;Jin, Yin-Zhe;Row, Kyung-Ho
    • Bulletin of the Korean Chemical Society
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    • 제25권12호
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    • pp.1807-1811
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    • 2004
  • Supercritical fluid chromatography (SFC) was considered for separating racemic ibuprofen. The chromatographic column (3.9 ${\times}$ 150 mm) was packed with Kromasil$^{\circledR}$ CHI-TBB, and the mobile phase was supercritical carbon dioxide with modifier of IPA. The experimental variables were the content of IPA, and temperature and pressure of supercritical mobile phase. To determine the separation condition, the empirical equation of retention factor and resolution was proposed. In the case of retention factor, the empirical equation was in the form, $k\;=\;a{\rho}\;+b/F\;+\;c\;({\rho}/F)\;+\;d$. The empirical equation for resolution was proposed as a linear form, $R\;=\;a{\rho}\;+\;bF\;+\;c$.

NOD2 signaling pathway is involved in fibronectin fragment-induced pro-catabolic factor expressions in human articular chondrocytes

  • Hwang, Hyun Sook;Lee, Mi Hyun;Choi, Min Ha;Kim, Hyun Ah
    • BMB Reports
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    • 제52권6호
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    • pp.373-378
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    • 2019
  • The nucleotide-binding and oligomerization domain (NOD) is an innate pattern recognition receptor that recognizes pathogen- and damage-associated molecular patterns. The 29-kDa amino-terminal fibronectin fragment (29-kDa FN-f) is a matrix degradation product found in the synovial fluids of patients with osteoarthritis (OA). We investigated whether NOD2 was involved in 29-kDa FN-f-induced pro-catabolic gene expression in human chondrocytes. The expression of mRNA and protein was measured using quantitative real-time polymerase chain reaction (qrt-PCR) and Western blot analysis. Small interfering RNAs were used for knockdown of NOD2 and toll-like receptor 2 (TLR-2). An immunoprecipitation assay was performed to examine protein interactions. The NOD2 levels in human OA cartilage were much higher than in normal cartilage. NOD1 and NOD2 expression, as well as pro-inflammatory cytokines, including interleukin-1beta (IL-$1{\beta}$) and tumor necrosis factor-alpha (TNF-${\alpha}$), were upregulated by 29-kDa FN-f in human chondrocytes. NOD2 silencing showed that NOD2 was involved in the 29-kDa FN-f-induced expression of TLR-2. Expressions of IL-6, IL-8, matrix metalloproteinase (MMP)-1, -3, and -13 were also suppressed by TLR-2 knockdown. Furthermore, NOD2 and TLR-2 knockdown data demonstrated that both NOD2 and TLR-2 modulated the expressions of their adaptors, receptorinteracting protein 2 (RIP2) and myeloid differentiation 88, in 29-kDa FN-f-treated chondrocytes. 29-kDa FN-f enhanced the interaction of NOD2, RIP2 and transforming growth factor beta-activated kinase 1 (TAK1), an indispensable signaling intermediate in the TLR-2 signaling pathway, and activated nuclear factor-${\kappa}B$ (NF-${\kappa}B$), subsequently leading to increased expressions of pro-inflammatory cytokines and cartilage-degrading enzymes. These results demonstrate that 29-kDa FN-f modulated pro-catabolic responses via cross-regulation of NOD2 and TLR-2 signaling pathways.

복합 전열 촉진 핀이 적용된 핀-관 열교환기의 성능에 대한 실험적 연구 (An Experimental Study on Air-Side Performance of Fin-and-Tube Heat Exchangers Having Compound Enhanced Fins)

  • 김내현
    • 한국산학기술학회논문지
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    • 제16권7호
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    • pp.4364-4374
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    • 2015
  • 본 연구에서는 복합 전열 촉진 핀 열교환기의 열전달 및 압력손실에 대하여 실험적으로 검토하였다. 비교를 위하여 널리 사용되는 루버 핀 열교환기에 대한 실험도 수행하였다. 핀 피치(1.5mm~1.7mm)와 열수(1열~3열)를 변화시키며 열전달 및 압력손실에 미치는 영향을 검토하였다. 실험범위에서 핀 피치가 j와 f 인자에 미치는 영향은 크지 않았다. 열수가 증가하면 j 인자는 감소하고 f 인자는 열수와 무관하였다. 루버 핀의 j와 f 인자가 복합 전열 촉진 핀의 값들보다 크게 나타났다. 1열의 경우 평균 j 인자와 f 인자는 23%, 27% 크고, 2열에서는 11%, 8%, 3열에서는 10%, 9% 크게 나타났다. 하지만 동일 압력 손실 대비 전열 성능은 복합 전열 촉진 핀 열교환기가 1열에서 6.4%, 2열에서 11.1%, 3열에서 13.6% 크게 나타났다. 기존 루버 핀 상관식은 j 인자를 과대 예측하고 f 인자를 과소 예측하였다.

[2,3]-FACTORS IN A 3-CONNECTED INFINITE PLANAR GRAPH

  • Jung, Hwan-Ok
    • Journal of applied mathematics & informatics
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    • 제10권1_2호
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    • pp.27-40
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    • 2002
  • For two integers m, n with m $\leq$ n, an [m,n]-factor F in a graph G is a spanning subgraph of G with m $\leq$ d$\_$F/(v) $\leq$ n for all v ∈ V(F). In 1996, H. Enomoto et al. proved that every 3-connected Planar graph G with d$\_$G/(v) $\geq$ 4 for all v ∈ V(G) contains a [2,3]-factor. In this paper. we extend their result to all 3-connected locally finite infinite planar graphs containing no unbounded faces.

Robustness for Omnibus Tests using Trimmed Means under Violated Assumptions

  • Hyunchul Kim
    • Communications for Statistical Applications and Methods
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    • 제4권2호
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    • pp.581-588
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    • 1997
  • Univariate F test is based on the multisample sphericity assumption. Robustness for tests of a main effect of the within-subjects factor was investigated when the assumptions of the onmibus F tests are violated in a split-plot design with one between-subjects factor using untrimmed data and trimmed data. The results indicate that when sample sizes are unbalanced and dispersion matrices are heterogeneous, the CIGA and the $CIGA_T$ tests better control Type I error rates than do the $F_T$test and the$\widetilde{\xi_T}$test.

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Tall fescue의 생육과 thatch 축적에 미치는 압력요인의 영향 (Effect of Rolling Factor on the Growth and Thatch Accumulation in Tall fescue.)

  • 이주삼;윤용범;이강욱;윤익석
    • 아시안잔디학회지
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    • 제1권1호
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    • pp.37-41
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    • 1987
  • Effect of Rolling factor on the growth and thatch accumulation in tall fescue was studied from the viewpoint of estimate the rolling factor to obtain the highest values of growth characters and analysis of thatch accumulation. Rolling factors were 1.82, 3.33, 4.29 and 4.85, respectively. The results are may he summarized as follows ; 1. Rolling factor was affected to obstructive on the growth of tall fescue. Thus, the rolling factor ( RF) had significant negative correlated with the dry weight of plant ( DW ), leaf weight (LW), stem weight (SW), dry weight of thatch (Th), number of tillers (NT) and C / F ratio. 2. Rolling factor of 1.82 was an adequate rolling factor for the growth. 3. The dry weight of thatch(Th) had significant positive correlated with DW, LW, and NT, but negative correlated with the dry weight of thatch per a tiller ( th / NT). 4. Thatch accumulation system can be shown in following diagram. yield compnents - DW ~ Th - Rf (LW, SW, NT, C/F) th/NT 5. The dry weight of thatch per a tiller(th / NT) was a concerning factor for the losses of thatch.

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주파수합성기의 Phase Noise 예측 및 1/f Noise Modeling (The Phase Noise Prediction and 1/f Noise Modeling of Frequency Synthesizer)

  • 김형도;성태경;조형래
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2000년도 추계종합학술대회
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    • pp.180-185
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    • 2000
  • 본 논문에서는 주파수합성기에서 가장 큰 노이즈 Source인 VCO 및 각 단에서 발생하는 Phase Noise의 offset 주파수에 따른 변화를 예측하기위해 2303,15MHz의 주파수합성기를 설계하고 Lascari의 방법을 이용해 분석하였다. 그리고 VCO에서 발생되는 여러 중첩 형태로 된 Phase Noise중 저주파대역에서 문제가 되는 1/f Noise룰 3차 System에서 분석하였다. 3차 System에서는 해석이 복잡하므로 수학적인 분석을 통하여 1/f Noise를 예측한다는 것이 어렵지만 pseudo-damping factor의 도입으로 3차 시스템에서의 1/f Noise variance의 해석이 용이하도록 시도하였고 이를 2차 시스템과 비교하여 분석하였다.

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