• Title/Summary/Keyword: ${\alpha}-Factor$

Search Result 4,720, Processing Time 0.038 seconds

A Study on the Crack Growth Behavior of a Inclined Crack in a Non-Uniform Thickness Material (두께가 일정하지 않은 재료에서 경사진 균열의 성장거동에 관한 연구)

  • 조명래;표창률;박종주;고명훈
    • Journal of the Korean Society of Safety
    • /
    • v.12 no.4
    • /
    • pp.27-38
    • /
    • 1997
  • The effect of geometry factors on the combined mode stress intensity factor behaviors of a slant crack in a non-uniform thickness material was analysed by 2-dimensional theoretical analysis. The analysis is based on the Laurent's series expansions of complex potentials where the complex coefficients of the series are determined from the compatibility and the equilibrium conditions of the thickness interface and the stress free conditions of the crack surface. In numerical calculations the perturbation technique is employed. The expressions for the crack tip stress intensity factor are given in the form of power series of dimensionless crack length $\lamda$, and the function of crack slant angle $\alpha$ and thickness ratio $\beta$. The results of numerical calculations for each problems are represented as the correction factors F($\lamda$, $\alpha$, $\beta$). The results clearly show the following characteristics : The correction factors of the combined mode stress intensity factors for a non-uniform thickness material can be defined in the form of F($\lamda$, $\alpha$, $\beta$). The stress intensity factor values for a given crack length are decreased with increase of thickness ratio $\beta$.

  • PDF

A Study on Scale Development for the On-line Image Consulting of Businessmen (직장남성의 이미지 컨설팅을 위한 측정도구 개발 - 인터넷 사용자를 중심으로 -)

  • Koh Ae-Ran;No Ji-Young
    • Journal of the Korean Home Economics Association
    • /
    • v.43 no.5 s.207
    • /
    • pp.93-105
    • /
    • 2005
  • This study focused on the development of scales measuring the characteristics related to appearance management behaviors of businessmen for on-line image consulting. The purposes of this study were, 1) to develop a tool which can measure the ideal image, 2) to develop a tool which can measure personality, and 3) to develop a scale measuring the physical characteristics and body cathexis. The data were collected from 380 businessmen in Seoul, Korea and were analyzed by frequency, factor analysis, reliability test, cluster analysis, correlation analysis, one-wav ANOVA and Duncan test. The results from this study were as follows .1)Five factors of the ideal image were identified: stylish, able, active, neat/confident and easy. The total variance was 74.29$\%$ and Cronbach's alpha of the 5 factors ranged from .74-.90. One item was selected to represent each factor. 2) Five factors of personality were identified: preference of social function, sociable, dynamic, achievement-motivated, and success-oriented. The totai variance was 60.63$\%$ and Cronbach's alpha ranged from .56-.83. One item was selected to represent each factor. 3) Five factors of body cathexis were identified: satisfaction with girth, length, physique, nose and eyes. The total variance was 73_46$\%$ and Cronbach's alpha ranged from .68-.85.

AN ANALYSIS OF THE EFFECT OF HYDRAULIC PARAMETERS ON RADIONUCLIDE MIGRATION IN AN UNSATURATED ZONE

  • Kim, Gye-Nam;Moon, Jei-Kwon;Lee, Kune-Woo
    • Nuclear Engineering and Technology
    • /
    • v.42 no.5
    • /
    • pp.562-567
    • /
    • 2010
  • A One-Dimensional Water Flow and Contaminant Transport in Unsaturated Zone (FTUNS) code has been developed in order to interpret radionuclide migration in an unsaturated zone. The pore-size distribution index (n) and the inverse of the air-entry value ($\alpha$) for an unsaturated zone were measured by KS M ISO 11275 method. The hydraulic parameters of the unsaturated soil are investigated by using soil from around a nuclear facility in Korea. The effect of hydraulic parameters on radionuclide migration in an unsaturated zone has been analyzed. The higher the value of the n-factor, the more the cobalt concentration was condensed. The larger the value of $\alpha$-factor, the faster the migration of cobalt was and the more aggregative the cobalt concentration was. Also, it was found that an effect on contaminant migration due to the pore-size distribution index (n) and the inverse of the air-entry value ($\alpha$) was minute. Meanwhile, migrations of cobalt and cesium are in inverse proportion to the Freundich isotherm coefficient. That is to say, the migration velocity of cobalt was about 8.35 times that of cesium. It was conclusively demonstrated that the Freundich isotherm coefficient was the most important factor for contaminant migration.

Developing Parenting Stress Scale for International Marriage Immigrant Women in South Korea: Focused on Vietnamese and Filipino Marriage Immigrant Women (여성결혼이민자의 양육 스트레스 측정도구 개발: 베트남과 필리핀 여성결혼이민자 중심으로)

  • Kim, Jung;Kim, Sun-Hee
    • Women's Health Nursing
    • /
    • v.24 no.1
    • /
    • pp.33-48
    • /
    • 2018
  • Purpose: The purpose of this study was to develop a scale to evaluate parenting stress of international marriage immigrant women from Vietnam and the Philippines. Methods: The concept of parenting stress of international marriage immigrant women was analysed with a hybrid model. Data were collected from 273 international marriage immigrant women from Vietnam and the Philippines who were raising their children aged 1 to 6 years. These collected data were subjected to exploratory factor analysis, multitrait/multi-item matrix assessment, Pearson correlation coefficient analysis, and Cronbach's alpha internal consistency measurement. Results: The final instrument consisted of 28 items. The following six factors were extracted by exploratory factor analysis: 'insufficiency of parenting support system', 'role burden of mothers', 'maladjustment of children', 'confusion of parenting methods due to cultural differences', 'unskilled Korean communication', and 'ordinary difficulties'. Construct validity (factor analysis, convergent validity, and discriminant validity) and criterion-related validity were confirmed. Cronbach's ${\alpha}$ value of total items was .92(95% CI .91-.94). Cronbach's ${\alpha}$ of values for these factors ranged from .76 to .85. Conclusion: The parenting stress scale for international marriage immigrant women is a valid and reliable tool.

Development of Web-based SWAT LUC with SWAT BFlow Alpha Factor and Slope-based CN modules (Web 기반의 SWAT LUC 및 BFlow Alpha factor와 경사도 기반 CN 모듈 개발)

  • Lee, Dongjun;Han, Jeongho;Sung, Yunsoo;Kim, Jonggun;Lim, Kyoung Jae
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2016.05a
    • /
    • pp.291-291
    • /
    • 2016
  • 토지이용변화는 환경 변화에 영향을 주는 대표적인 인자이기 때문에 수문 모델링에 있어서 상당히 중요하다. 특히 급격한 도시화가 이루어지는 지역에 대해서는 토지이용변화를 반드시 고려하여야 한다. 인구와 지형자료를 이용하여 토지이용변화를 모의할 수 있는 CLUE-S 모델이 개발되었지만 아직까지 대부분 수문모델은 토지이용변화를 고려하지 못하고 있었다. 이에 Pai, N. 와 D. Saraswat은 SWAT2009_LUC Tool를 개발하여 시공간적으로 변화하는 토지를 고려한 수문모의를 가능하도록 하였다. 하지만 SWAT2009_LUC는 새로운 종류의 토지이용종류를 고려할 수 없어 유역 내 새로운 토지이용도가 추가될 시 이를 모의할 수 없다는 단점을 가지고 있다. 이러한 단점을 극복하기 위해서 Friedrich J. Koch Koch는 Land use Update and Soil Assessment(LUPSA)를 개발하여 새로운 토지이용도 및 변화된 토지이용도의 경사도를 추가적으로 고려할 수 있도록 하였다. 하지만 LUPSA 모듈은 공개되어 있지 않다. 따라서 본 연구에서는 SWAT 사용자들이 토지이용변화를 많이 고려할 수 있도록 Web 기반의 LUC 모듈을 개발하였으며, SWAT BFlow Alpha Factor와 경사도 기반의 CN을 산정할 수 있는 모듈을 추가하였다. 본 연구에서 개발된 Web 기반의 LUC는 국내뿐만 아니라 해외 SWAT 사용자들로 하여금 급격하게 토지가 변화한 유역에 대해 정확한 수문모의를 하는데 기여할 것이라 판단된다.

  • PDF

Anti-inflammatory Activity of the Methanol Extract from the Stem of Coriandrum Sativum in RAW 264.7 Cells

  • Jung, Ji Yun;Park, Chung A
    • The Korea Journal of Herbology
    • /
    • v.33 no.5
    • /
    • pp.73-79
    • /
    • 2018
  • Objectives : Coriandrum sativum is a medicinal herb that is used to enhance organoleptic quality and food flavor and as source of natural antioxidants. This research investigated the anti-inflammatory activity of Coriandrum sativum stem methanol extract (CSSE) using RAW 264.7 cells. Methods : Production of tumor necrosis factor-${\alpha}$(TNF-${\alpha}$), interleukin (IL)-$1{\beta}$, IL-6, and nitric oxide (NO) in the culture supernatant, protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor-kappa B (NF-${\kappa}B$) in the extract were assayed. Results : Treatment with CSSE ($100{\mu}g/m{\ell}$) resulted in inhibited levels of protein expression of lipopolysaccharide- (LPS-) induced iNOS, COX-2, and NF-${\kappa}B$ as well as production of TNF-${\alpha}$, IL-$1{\beta}$, IL-6, and NO induced by LPS. Conclusions : These results demonstrate that CSSE exhibits anti-inflammatory activities via decreasing production of pro-inflammatory mediators through suppression of the pathways of NF-${\kappa}B$ in LPS-induced RAW 264.7 cells. Thus, CSSE may have therapeutic potential for a variety of inflammation-mediated diseases.

TNFα-induced Down-Regulation of Estrogen Receptor α in MCF-7 Breast Cancer Cells

  • Lee, Sang-Han;Nam, Hae-Seon
    • Molecules and Cells
    • /
    • v.26 no.3
    • /
    • pp.285-290
    • /
    • 2008
  • Estrogen-induced proliferation in estrogen receptor (ER)-positive breast cancer cells is primarily mediated through two distinct intracellular receptors, $ER{\alpha}$ and $ER{\beta}$. Although tumor necrosis factor alpha ($TNF{\alpha}$) and $E2/ER{\alpha}$ are known to exert opposing effects on cell proliferation in MCF-7 cells, the mechanism by which $TNF{\alpha}$ antagonizes $E2/ER{\alpha}$-mediated cell proliferation is not well understood. The present study suggests that reduced cell survival in response to $TNF{\alpha}$ treatment in MCF-7 cells may be associated with the down-regulation of $ER{\alpha}$ protein. The decrease in $ER{\alpha}$ protein level was accompanied by an inhibition of $ER{\alpha}$ gene transcription. Cell viability was decreased synergistically by the combined treatment with $ER{\alpha}$-siRNA and $TNF{\alpha}$. Furthermore, pretreatment of cells with the PI3-kinase (PI3K)/ Akt inhibitor, LY294002, markedly enhanced $TNF{\alpha}$-induced down-regulation of the $ER{\alpha}$ protein, suggesting that the PI3K/Akt pathway might be involved in control of the $ER{\alpha}$ level. Moreover, down-regulation of $ER{\alpha}$ by $TNF{\alpha}$ was not inhibited in cells that were pretreated with the proteasome inhibitors, MG132 and MG152, which suggests that proteasome-dependent proteolysis does not significantly influence $TNF{\alpha}$-induced down-regulation of $ER{\alpha}$ protein. In contrast, the effect of the PI3K/Akt inhibitor on $ER{\alpha}$ was blocked in cells that were treated with LY294002 in the presence of the proteasome inhibitors. Collectively, our findings show that the $TNF{\alpha}$ may partly regulate the growth of MCF-7 breast cancer cells through the down-regulation of $ER{\alpha}$ expression, which is primarily mediated by a PI3K/Akt signaling.

High Throughput Fluorogenic Assay for TNF-alpha Converting Enzyme(TACE) inhibitors

  • Keum, Se-Hoon;Lee, Bong-Yong
    • Proceedings of the PSK Conference
    • /
    • 2003.04a
    • /
    • pp.125.2-126
    • /
    • 2003
  • Human tumor necrosis factor-alpha (TNFa) is a key pro-inflammatory cytokine produced by activated monocytes and macrophage as a part of the self-defence machinery. TNF-a converting enzyme (TACE) is the metalloproteinase that processes the membrane bound precursor of TNFa to the soluble component. (omitted)

  • PDF

Anti-allergic Effect of Bopyeoyangyeong-jun to Cytokines and Transcription (보폐양영전(保肺養營煎)이 알레르기 염증반응에서 Cytokines 및 Transcription에 미치는 영향)

  • Lee, Jae-Hyuk;Kim, Hong-Gi;Shin, Woo-Jin;Kim, Jin-Young;Park, Dong-Il
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.23 no.1
    • /
    • pp.127-134
    • /
    • 2009
  • In the present study, we investigated the anti-allergic effect of the water extract of Bopyeoyangyeong-jun(BYJ) to cytokines and transcription. To investigate the biological effect of BYJ, We examined cytotoxicity and inflammatory cytokine secretion with RBL-2H3. We examined tumor necrosis factor-alpha(TNF-$\alpha$), interleukin(IL)-4 secretion from RBL-2H3 cell after pre- treatment with Bopyeoyangyeong-jun of $1\;mg/m{\ell}$, $2\;mg/m{\ell}$. RBL-2H3 cell was stimulated with phorbol 12-myristate 13-acetate(PMA) and calcium ionophore A23187. We observed that Bopyeoyangyeong-jun reduced TNF-$\alpha$, IL-4 secretion and mRNA expression in RBL-2H3 cells. Moreover, the expression of levels of cyclooxygenase (COX)-2 mRNA, nuclear factor-kappa B (NF-${\kappa}B$) (p65) protein, ERK MAPK, and the degradation of level inhibitor kappa B-alpha ($I{\kappa}B-{\alpha}$) were down-regulated by BYJ. Taken together, these results indicate that Bopyeoyangyeong-jun hascontrols TNF-$\alpha$, IL-4 secretion on allergic reaction.