• Title/Summary/Keyword: Line of Action

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Wind velocity field during thunderstorms

  • Ponte, Jacinto Jr.;Riera, Jorge D.
    • Wind and Structures
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    • v.10 no.3
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    • pp.287-300
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    • 2007
  • Wind action is a factor of fundamental importance in the structural design of light or slender constructions. Codes for structural design usually assume that the incident mean wind velocity is parallel to the ground, which constitutes a valid simplification for frequent winds caused by meteorological phenomena such as Extratropical Storms (EPS) or Tropical Storms. Wind effects due to other phenomena, such as thunderstorms, and its combination with EPS winds in so-called squall lines, are simply neglected. In this paper a model that describes the three-dimensional wind velocity field originated from a downburst in a thunderstorm (TS) is proposed. The model is based on a semi empirical representation of an axially-symmetrical flow line pattern that describes a stationary field, modulated by a function that accounts for the evolution of the wind velocity with time. The model allows the generation of a spatially and temporally variable velocity field, which also includes a fluctuating component of the velocity. All parameters employed in the model are related to meteorological variables, which are susceptible of statistical assessment. A background wind is also considered, in order to account for the translational velocity of the thunderstorm, normally due to local wind conditions. When the translation of the TS is caused by an EPS, a squall line is produced, causing the highest wind velocities associated with TS events. The resulting vertical velocity profiles were also studied and compared with existing models, such as the profiles proposed by Vicroy, et al. (1992) and Wood and Kwok (1998). The present model predicts horizontal velocity profiles that depend on the distance to the storm center, effect not considered by previous models, although the various proposals are globally compatible. The model can be applied in any region of interest, once the relevant meteorological variables are known, to simulate the excitation due to TS winds in the design of transmission lines, long-span crossings, cable-stayed bridges, towers or similar structures.

Effect of Tea Polyphenols on Anticancer Activity and Cytokines Production (차 폴리페놀화합물의 사이토카인 생성 및 항암능에 대한 영향)

  • Shon, Mi-Yae;Nam, Sang-Hae
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1354-1360
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    • 2007
  • Theaflavins (TF) and thearubigins (TR) are constituents of tea pigments which are polyphenols derived from Korean fermentation tea. After TF, TR and [(-) epigallocatechin-3-gallate](EGCG) have been applied to macrophage cell line (RAW264.7) nitric oxide (NO) synthesis and cytokines production were estimated. Cytokines production by enzyme linked immune-sorbent assay (ELISA) determined. NO production was increased by about 1.5-folds at the dose of $80\;{\mu}g/ml$ compared to control and lipopolysaccharide (LPS) stimulation when TF, TR and EGCG were applied to a RAW264.7 cell. Interleukin-6 (IL-6), Tumor necrosis factor ($TNF-{\alpha}$) and granulocyte-macrophage colony stimulating factor (GM-CSF) increased depended on concentrations of TF, TR and EGCG. The production of tumor necrosis $factor-{\alpha}$ increased highly in TR, TF and EGCG group with LPS. These results suggest that TF, TR and EGCG have immune-enhancement effect through the cytokine production. TF, TR and EGCG inhibited cancer cell viability, the anticancer effect of these polyphenols may explain the anti-tumor promotion action and antioxidant activity of these tea constituents.

A Study on Wind-drift Sand Deposition by Vegetation and Coastal Debris using a Wind Tunnel Test (식생 및 해안표착물에 의한 비사 퇴적 풍동실험 연구)

  • Je, Young Jun;Jeon, Yong Ho;Yoon, Han Sam
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.16 no.3
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    • pp.163-170
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    • 2013
  • The correlation and interaction mechanisms between marine debris and the vegetation zone were studied on the Jinu-do natural beach of the Nakdong river estuary. Laboratory wind tunnel experiments were carried out under the wind-field and bottom-sand conditions using wind tunnel test equipment to investigate the sedimentation characteristics of wind-drift sand deposition around marine debris and the vegetation zone. The major environmental factors/loads considered in this study were the motion of sand by wind on the beach, deposition of marine debris, and change in the vegetation zone/line. When the marine debris was installed in the wind tunnel, deposition at the front of the structure appeared first by wind action, and then deposition developed from behind at 70% of the front ground level. In contrast, in the case of vegetation, the deposition phenomenon appeared first from behind the vegetation zone/line, and was 60% higher than the front. When the height of the debris and vegetation was the same, the required experimental time to bury the vegetation completely was about twice that of the marine debris.

The Design of a Multimedia Data Management and Monitoring System for Digital Rights Protection using License Agent (라이선스 에이전트를 이용한 디지털 저작권 보호를 위한 멀티미디어 데이터 관리 및 감시 시스템의 설계)

  • Park, Jae-Pyo;Lee, Kwang-Hyung;Kim, Won;Jeon, Moon-Seok
    • Journal of the Korea Computer Industry Society
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    • v.5 no.2
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    • pp.281-292
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    • 2004
  • As the logistic environment of digital contents is rapidly changing, the protection of the digital rights for digital content has been recognized as one of critical Issues. Digital Right Management(DRM) has taken much interest Internet Service Provider(ISP), authors and publishers of digital content as an interested approach to create a trusted environment for access and use of digital resources. This paper propose an interested digital rights protection scheme using license agent to address problems facing contemporary DRM approached : static digital rights management, and limited application to on-line environment. We introduce a dynamic mission control technology to realize dynamic digital rights management. And we incorporate license agent to on- and off-line monitoring and tracking. The proposed system prevent illegal access and use by using PKI security method, real time action monitoring for user, data security for itself.

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The Manipulation Argument: Ernie, Diana, and Lightning Strike (조작논증과 어니, 다이애나, 번개)

  • Kim, Seahwa
    • Korean Journal of Logic
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    • v.22 no.2
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    • pp.233-251
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    • 2019
  • In this paper, I raise objections to Sungsu Kim's argument that Sartorio's hard-line reply to the manipulation argument fails. In attacking Sartorio's argument, Sungsu Kim claims that there are two problems with Sartorio's. I argue that Sungsu Kim's argument fails by responding to these two problems. With respect to the first problem, I provide a new example of dilution of responsibility. With respect to the second problem, I argue that, contrary to what Sungsu Kim assumes, for Sartorio's argument to succeed, our intuition that Ernie is responsible in the Lightning Strike Scenario does not have to be as strong as our intuition that Ernie is not responsible in the Diana scenario.

Effect of Bamboo salt-pro on carries-inducing properties of Streptococcus mutans

  • Shin, Hye-Young;You, Hyeon-Hee;Shin, Tae-Yong;Kim, Hyung-Min;You, Yong-Ouk
    • Advances in Traditional Medicine
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    • v.3 no.1
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    • pp.40-45
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    • 2003
  • We studied the effect of Bamboo salt-pro on the growth and acid production of S. mutans. The growth of S.mutans was reduced by the presence of the Bamboo salt-pro (1 mg/ml) and NaCl (1 mg/ml) significantly, and the positive control group (1 % of NaF) also exhibited antibacterial activity significantly. Bamboo salt-pro (1 mg/ml) reduced the rate of acid production by S. mutans. Bamboo salt alone did not demonstrate such a reduction in acid production at the concentration of 1 mg/ml. The inhibitory action of Bamboo salt-pro on acid production was found at a concentration of 1 mg/ml, but bamboo salt alone was not at a concentration of 1 mg/ml. In addition, we investigated the anti-inflammatory effect of Bamboo salt-pro on human mast cell line HMC-1. Bamboo salt-pro (0.1 and 0.01 mg/ml) inhibited significantly the secretion of inflammatory cytokine, tumor necrosis factor-a with $59.47{\pm}0.15%$, $51.98{\pm}0.16%$ respectively. Our results suggest that Bamboo salt-pro importantly contributes to the prevention or treatment of periodontitis and other oral diseases and inflammatory diseases.

Local buckling and shift of effective centroid of cold-formed steel columns

  • Young, Ben
    • Steel and Composite Structures
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    • v.5 no.2_3
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    • pp.235-246
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    • 2005
  • Local buckling is a major consideration in the design of thin-walled cold-formed steel sections. The main effect of local buckling in plate elements under longitudinal compressive stresses is to cause a redistribution of the stresses in which the greatest portion of the load is carried near the supporting edges of the plate junctions. The redistribution produces increased stresses near the plate junctions and high bending stresses as a result of plate flexure, leading to ultimate loads below the squash load of the section. In singly symmetric cross-sections, the redistribution of longitudinal stress caused by local buckling also produces a shift of the line of action of internal force (shift of effective centroid). The fundamentally different effects of local buckling on the behaviour of pin-ended and fixed-ended singly symmetric columns lead to inconsistencies in traditional design approaches. The paper describes local buckling and shift of effective centroid of thin-walled cold-formed steel channel columns. Tests of channel columns have been described. The experimental local buckling loads were compared with the theoretical local buckling loads obtained using an elastic finite strip buckling analysis. The shift of the effective centroid was also compared with the shift predicted using the Australian/New Zealand and American specifications for cold-formed steel structures.

Trigeminal neuralgia management after microvascular decompression surgery: two case reports

  • Hwang, Victor;Gomez-Marroquin, Erick;Enciso, Reyes;Padilla, Mariela
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.20 no.6
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    • pp.403-408
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    • 2020
  • Trigeminal neuralgia (TN) involves chronic neuropathic pain, characterized by attacks of repeating short episodes of unilateral shock-like pain, which are abrupt in onset and termination. Anticonvulsants, such as carbamazepine, are the gold standard first-line drugs for pharmacological treatment. Microvascular decompression (MVD) surgery is often the course of action if pharmacological management with anticonvulsants is unsuccessful. MVD surgery is an effective therapy in approximately 83% of cases. However, persistent neuropathic pain after MVD surgery may require reintroduction of pharmacotherapy. This case report presents two patients with persistent pain after MVD requiring reintroduction of pharmacological therapy. Although MVD is successful for patients with failed pharmacological management, it is an invasive procedure and requires hospitalization of the patient. About one-third of patients suffer from recurrent TN after MVD. Often, alternative treatment protocols, including the reintroduction of medications, may be necessary to achieve improvement. This case report presents two cases of post-MVD recurrent pain. Further research is lacking on the success rates of subsequent medication therapy after MVD has proven less effective in managing TN.

Coupled dynamic responses of a semisubmersible under the irregular wave and turbulent wind

  • Dey, Swarnadip;Saha, Kaushik;Acharya, Pooja;Roy, Shovan;Banik, Atul K.
    • Ocean Systems Engineering
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    • v.8 no.4
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    • pp.441-459
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    • 2018
  • A coupled dynamic analysis of a semisubmersible-type FOWT has been carried out in time domain under the combined action of irregular wave and turbulent wind represented respectively by JONSWAP spectrum and Kaimal spectrum. To account for the turbine-floater motion coupling in a more realistic way, the wind turbulence has been incorporated into the calculation of aerodynamic loads. The platform model was referred from the DeepCwind project and the turbine considered here was the NREL 5MW Baseline. To account for the operationality of the turbine, two different environmental conditions (operational and survival) have been considered and the aerodynamic effect of turbine-rotation on actual responses of the FOWT has been studied. Higher mean offsets in surge and pitch responses were obtained under the operational condition as compared to the survival condition. The mooring line tensions were also observed to be sensitive to the rotation of turbine due to the turbulence of wind and overestimated responses were found when the constant wind was considered in the analysis. Additionally, a special analysis case of sudden shutdown of the turbine has also been considered to study the swift modification of responses and tension in the mooring cables.

The Effects of five kinds of Artemisia capillaris $T_{HUNB}$ fractions on Cell Viability, Cell Cycle Progression and Fas-mediated Apoptosis of HepG2 Cells (인진(茵陳)분획물이 간세포활성, 세포주기 및 Fas-mediated Apoptosis에 미치는 영향)

  • Kim, Young-Chul;Lee, Jang-Hoon;Woo, Hong-Jung;Yi, Jong-Hoon
    • The Journal of Internal Korean Medicine
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    • v.21 no.3
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    • pp.363-368
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    • 2000
  • Objective : This study was carried out to examine the effect of five fractions of an aqueous extract from Artemisia capillaris $T_{HUNB}$. Methods : The queous extract from Artemisia capillaris $T_{HUNB}$. was fractionized into 5 kinds of material. We observed the effect of each fractions on etoposide-induced apoptosis, cell viability, cell cycle progression and mRNA expression of apoptosis-related genes in human hepatocyte cell line HepG2. Results and Conclusions : The data shows that butanol fraction of Artemisia capillaris $T_{HUNB}$. has no relation with cell cycle, however, it inhibits apoptosis significantly and the action may be due to the suppression of Fas and Sax genes and activation of Bcl-2 gene.

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