• Title/Summary/Keyword: combined effects

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Dynamic responses of a riser under combined excitation of internal waves and background currents

  • Lou, Min;Yu, Chenglong
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.6 no.3
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    • pp.685-699
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    • 2014
  • In this study, the dynamic responses of a riser under the combined excitation of internal waves and background currents are studied. A modified Taylor-Goldstein equation is used to calculate the internal waves vertical structures when background currents exist. By imposing rigid-lid boundary condition, the equation is solved by Thompson-Haskell method. Based on the principle of virtual work, a nonlinear differential equation for riser motions is established combined with the modified Morison formula. Using Newmark-${\beta}$ method, the motion equation is solved in time domain. It is observed that the internal waves without currents exhibit dominated effect on dynamic response of a riser in the first two modes. With the effects of the background currents, the motion displacements of the riser will increase significantly in both cases that wave goes along and against the currents. This phenomenon is most obviously observed at the motions in the first mode.

Effective impulse impedances of a deep-driven ground rod combined with other grounding electrodes (다른 형상의 접지전극에 접속된 심매설 접지전극의 실효임펄스임피던스)

  • Lee, Bok-Hee;Chang, Keun-Chul;Lee, Su-Bong
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2004.05a
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    • pp.565-569
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    • 2004
  • This paper deals with the characteristics of potential rise and effective impulse impedance of deep-driven ground rods that are used in high resistivity soil or in confined places such as downtown. Also the effects of the impulse and fault currents on the deep-driven ground rods combined with different type grounding electrodes like as mesh grids and counterpoises are described. The $8/20{\mu}s$ impulse current and other wave currents with different rise times are injected into the test ground rod and the effective impedances are examined. The most effective way to obtain the fine transient impedance behaviors of deep-driven ground rods is to reduce the inductive component of grounding electrode systems combined with other ground electrodes.

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Inverse Boundary Temperature Estimation in a Two-Dimensional Cylindrical Enclosure Using Automatic Differentiation and Broyden Combined Method (자동미분법과 Broyden 혼합법을 이용한 2차원 원통형상에서의 경계온도 역추정)

  • Kim Ki-Wan;Kim Dong-Min;Baek Seung-Wook
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.3 s.246
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    • pp.270-277
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    • 2006
  • Inverse radiation problems were solved for estimating boundary temperature distribution in a way of function estimation approach in an axisymmetric absorbing, emitting and scattering medium, given the measured radiative data. In order to reduce the computational time fur the calculation of sensitivity matrix, automatic differentiation and Broyden combined method were adopted, and their computational precision and efficiency were compared with the result obtained by finite difference approximation.. In inverse analysis, the effects of the precision of sensitivity matrix, the number of measurement points and measurement error on the estimation accuracy had been inspected using quasi-Newton method as an inverse method. Inverse solutions were validated with the result acquired by additional inverse methods of conjugate-gradient method or Levenberg-Marquardt method.

Burn Wound Successfully Treated with 830-nm Light Emitting Diode Phototherapy Combined with Epidermal Growth Factor Solution

  • Lee, Hae-Jin;Kim, Young Koo
    • Medical Lasers
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    • v.8 no.2
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    • pp.94-96
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    • 2019
  • Burns are one of the most extensive injuries of soft tissues as well as skin, occasionally resulting in extensive, deep wounds and death. Burn wounds can lead to severe physical and psychological distress because of excessive scarring and skin contractures. Treatment of burn wounds has always been a challenging problem and many different methods have been used to treat such injuries. We report here on treating a patient with a burn wound using 830-nm light emitting diode (LED) phototherapy combined with epidermal growth factor (EGF) solution. After five daily sessions of LED with EGF solution treatment, the patient demonstrated nearly complete improvement with no remarkable side effects. We suggest that LED phototherapy combined with EGF solution could be an effective and safe treatment option for treating burn wounds.

Failure simulation of nuclear pressure vessel under severe accident conditions: Part I - Material constitutive modeling

  • Eui-Kyun Park;Ji-Su Kim;Jun-Won Park;Yun-Jae Kim;Yukio Takahashi;Kukhee Lim
    • Nuclear Engineering and Technology
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    • v.55 no.11
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    • pp.4146-4158
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    • 2023
  • This paper proposes a combined plastic and creep constitutive model of A533B1 pressure vessel steel to simulate progressive deformation of nuclear pressure vessels under severe accident conditions. To develop the model, recent tensile test data covering a wide range of temperatures (from RT to 1,100 ℃) and strain rates (from 0.001%/s to 1.0%/s) was used. Comparison with experimental data confirms that the proposed combined plastic and creep model can well reflect effects of temperature and strain rate on tensile behaviour up to failure. In the companion paper (Part II), the proposed model will be used to simulate OECD lower head failure (OLHF) test data.

Effects of Dietary Yogurt: Changes in Blood Components on Healthy Men Smokers (식이 요거트의 효과: 흡연남성에게서 요거트에 의한 혈액성분의 변화)

  • Kim, Hyun-Kyung;Kweon, Chang-Oh;Kim, Byung-Won;Kim, Soo-Hwan;Ryu, Jae-Ki
    • Korean Journal of Clinical Laboratory Science
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    • v.52 no.2
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    • pp.105-111
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    • 2020
  • Smoking is associated with increased inflammation and is a risk factor for a range of diseases. Conversely, yogurt has beneficial effects on health. This study examined the effects of yogurt consumption on the hematological parameters and fibrinogen levels in smokers. The participants were categorized into four groups. Non-smokers were assigned to the control and yogurt groups while smokers were assigned to the smoking and combined (yogurt plus smoking) groups. The participants consumed yogurt, and either smoked or did not smoke for three weeks. The changes in hematological parameters and fibrinogen levels were examined. In the combined group, the proportion of neutrophils and fibrinogen levels increased significantly, whereas the lymphocyte proportion decreased. The eosinophil proportion increased significantly in the Smoking group, but no change was observed in the combined group. In addition, the mean corpuscular hemoglobin concentration increased in the smoking and combined groups, indicating that smoking may affect the lifespan of red blood cells. In conclusion, this study showed that yogurt consumption might influence the immune function by modulating the levels of neutrophils, lymphocytes, and fibrinogen in smokers. Furthermore, the absence of any increase in the eosinophil proportion in the combined group, unlike in the smoking group, suggests that yogurt consumption may have an inhibitory effect on allergic reactions.

Hall and Ion-Slip effects on magneto-micropolar fluid with combined forced and free convection in boundary layer flow over a horizontal plate

  • Seddeek, M.A.;Abdelmeguid, M.S.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.8 no.2
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    • pp.51-73
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    • 2004
  • A boundary layer analysis is used to study the effects of Hall and ion-slip currents on the steady magneto-micropolar of a viscous incompressible and electrically conducting fluid over a horizontal plate. By means of similarity solutions, deviation of fundamental equations on the assumption of small magnetic Reynolds number are solved numerically by using the shooting method. The effects of various parameters of the problem, e.g. the magnetic parameter, Hall parameter, ion-slip parameter, buoyancy parameter and material parameter are discussed and shown graphically.

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Gelam Honey and Ginger Potentiate the Anti Cancer Effect of 5-FU against HCT 116 Colorectal Cancer Cells

  • Hakim, Luqman;Alias, Ekram;Makpol, Suzana;Ngah, Wan Zurinah Wan;Morad, Nor Azian;Yusof, Yasmin Anum Mohd
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4651-4657
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    • 2014
  • The development of chemopreventive approaches using a concoction of phytochemicals is potentially viable for combating many types of cancer including colon carcinogenesis. This study evaluated the anti-proliferative effects of ginger and Gelam honey and its efficacy in enhancing the anti-cancer effects of 5-FU (5-fluorouracil) against a colorectal cancer cell line, HCT 116. Cell viability was measured via MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphenyl)-2H-tetrazolium) assay showing ginger inhibiting the growth of HCT 116 cells more potently ($IC_{50}$ of 3mg/mL) in comparison to Gelam honey ($IC_{50}$ of 75mg/mL). Combined treatment of the two compounds (3mg/mL ginger+75mg/mL Gelam honey) synergistically lowered the $IC_{50}$ of Gelam honey to 22mg/mL. Combination with 35 mg/mL Gelam honey markedly enhanced 5-FU inhibiting effects on the growth of HCT 116 cells. Subsequent analysis on the induction of cellular apoptosis suggested that individual treatment of ginger and Gelam honey produced higher apoptosis than 5-FU alone. In addition, treatment with the combination of two natural compounds increased the apoptotic rate of HCT 116 cells dose-dependently while treatment of either ginger or Gelam honey combined with 5-FU only showed modest changes. Combination index analysis showed the combination effect of both natural compounds to be synergistic in their inhibitory action against HCT 116 colon cancer cells (CI 0.96 < 1). In conclusion, combined treatment of Gelam honey and ginger extract could potentially enhance the chemotherapeutic effect of 5-FU against colorectal cancer.

Effects of Ultraviolet-B Radiation on Growth and Photosynthesis in Cucumber Primary Leaves

  • Kim, Hyo-Jin;Kim, Tae-Yun;Hong, Jung-Hee
    • Journal of Environmental Science International
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    • v.15 no.12
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    • pp.1093-1101
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    • 2006
  • In the present study we studied the growth, photosynthetic traits and protective mechanisms against oxidative stress in the primary loaves of cucumber (Cucumis sativus L.) seedlings with or without UV-B treatment. Cucumber seedings were irradiated with UV-B for 10 days in environment-controlled growth chambers. The primary leaves irradiated with UV-B showed reduction in leaf length and decreased biomass production. The reduced biomass production seemed to be due to a negative effect of UV-B radiation on the photosynthetic process. Changes in chemical properties of leaf, such as chi a/b ratio affected photosynthesis. UV-B significantly affected chl b content compared with chi a in the light harvesting complex resulting reduced photosynthetic activity Fv/Fm decreased with an UV-B stress, suggesting that the photosynthetic apparatus, and particularly, PS II was damaged under UV-B stress. Malondialdehyde(MDA) concentration which represents the state of membrane lipid peroxidation Increased significantly under UV-B stress confirming an oxidative stress. UV-B exposure with SA solution(0.1-1.0 mM) can partially ameliorated some of the detrimental effects of UV-B stress. Leaf injuries including loss of chlorophyll and decreased ratio of Fv/Fm were reduced with combined application of UV-B and SA. ABA and JA showed similar mode of action in physiological effects on photosynthetic activities though the levels were lower than those from SA treated plants. Chloroplast ultrastructure was also affected by UV-B exposure. The thickness of leaf tissue components decreased and the number of grana and thylakoids was reduced in chloroplast applied UV-B or SA alone. At combined stress granal and stromal thylakoids were less affected. The leaves under combined stress acquired a significant tolerance to oxidative stress. From these results, it can be suggested that SA may have involved a protective role against UV-B induced oxidative damage.

An exploratory study for an evidence of electroencephalographic changes in isolated subjects for distant mental intention

  • Kim, Dae-Keun
    • Science of Emotion and Sensibility
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    • v.17 no.4
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    • pp.51-60
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    • 2014
  • This double-blind study, as a human experiment of nonlocality, investigated the effects of senders' intention on the central nervous system of a distant human receiver and it explored the roles that motivation might have in modulating these effects. Whole brain activity was measured in the receiver whom was asked to relax in a distant room for 16 minutes; the sending person directed intention of oneness toward the receiver during repeated variable-second epochs separated by variable-second non-intention epochs. The total length of intention epochs and that of nonintention epochs were balanced. Eighteen sessions were conducted. In 9 of those sessions, the sender was the receiver's lover. In another 9 of those sessions, the sender was just acquainted with the receiver before the session. The receiver's whole brain activity recorded during the intention epochs were compared with the same measures recorded during the nonintention epochs used as controls. The statistical difference between the intentions versus controls across 18 sessions was examined by paired-t test. In addition, subgroup analysis for the 9 couple sessions and 9 non-couple sessions were additionally examined by the same test. The effect of distant intentionality decreased slow waves or increased EEG fast waves mainly in frontal regions, and increased EEG coherence during the intention epochs. The effects was not statistically significant after Bonferroni correction, but the couple sessions combined showed the largest effect followed by all sessions combined. Non-couple sessions combined showed the smallest effect. The changes in EEG power mean that receiver participants became more alert during the intention epochs and the change in EEG coherence might be evidence of coherent heart influence on EEG activity. Planned comparison with specific hypothesis testing for the suggested changes in this study have to be followed for an evidence of electroencephalographic changes in isolated subjects for the distant mental intention.