• Title/Summary/Keyword: key factor

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A case study of gust factor characteristics for typhoon Morakat observed by distributed sites

  • Liu, Zihang;Fang, Genshen;Zhao, Lin;Cao, Shuyang;Ge, Yaojun
    • Wind and Structures
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    • v.35 no.1
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    • pp.21-34
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    • 2022
  • Gust factor is an important parameter for the conversion between peak gust wind and mean wind speed used for the structural design and wind-related hazard mitigation. The gust factor of typhoon wind is observed to show a significant dispersion and some differences with large-scale weather systems, e.g., monsoons and extratropical cyclones. In this study, insitu measurement data captured by 13 meteorological towers during a strong typhoon Morakot are collected to investigate the statistical characteristics, height and wind speed dependency of the gust factor. Onshore off-sea and off-land winds are comparatively studied, respectively to characterize the underlying terrain effects on the gust factor. The theoretical method of peak factor based on Gaussian assumption is then introduced to compare the gust factor profiles observed in this study and given in some building codes and standards. The results show that the probability distributions of gust factor for both off-sea winds and off-land winds can be well described using the generalized extreme value (GEV) distribution model. Compared with the off-land winds, the off-sea gust factors are relatively smaller, and the probability distribution is more leptokurtic with longer tails. With the increase of height, especially for off-sea winds, the probability distributions of gust factor are more peaked and right-tailed. The scatters of gust factor decrease with the mean wind speed and height. AS/NZ's suggestions are nearly parallel with the measured gust factor profiles below 80m, while the fitting curve of off-sea data below 120m is more similar to AIJ, ASCE and EU.

Two-factor Authentication technology based on Key-Stroke (Key-Stroke 기반 Two-Factor 인증 기술)

  • An, Jun-Yeon;Ko, Gwang-Feel;Lee, Tae-jin
    • Convergence Security Journal
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    • v.20 no.3
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    • pp.29-37
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    • 2020
  • Password based authentication technology is yet certain and id to provide a level of security being used in most systems, but already a myriad of personal information exposure to the accident. Above all, and once exposed, it is difficult to recover the password. Thus, the various authentication techniques - factor two was introduced, but they are expensive and discomfort to users, to lead. In this paper, the existing unique to users in such a single accreditation process / password id key - stroke, user authentication and cost effectively and at the same time. And not cause discomfort, suggested technologies that can also ensure high security exposure, password id. This paper's proposals and determine the effectiveness of the system to build model.

Comparison of Alpha-Factor Preprosequence and a Classical Mammalian Signal Peptide for Secretion of Recombinant Xylanase xynB from Yeast Pichia pastoris

  • He, Zuyong;Huang, Yuankai;Qin, Yufeng;Liu, Zhiguo;Mo, Delin;Cong, Peiqing;Chen, Yaosheng
    • Journal of Microbiology and Biotechnology
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    • v.22 no.4
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    • pp.479-483
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    • 2012
  • The secretory efficiency of recombinant xylanase xynB from yeast Pichia pastoris between the ${\alpha}$-factor preprosequence and a classical mammalian signal peptide derived from bovine ${\beta}$-casein was compared. The results showed that although the bovine ${\beta}$-casein signal peptide could direct high-level secretion of recombinant xylanase, it was relatively less efficient than the ${\alpha}$-factor preprosequence. In contrast, the bovine ${\beta}$-casein signal peptide caused remarkably more recombinant xylanase trapped intracellularly. Real-time RT-PCR analysis indicated that the difference in the secretory level between the two signal sequences was not due to the difference in the transcriptional efficiency.

On Equipment Replacement Models (장비교체모델에 대하여)

  • 박순달;이창훈;박철호
    • Journal of the Korean Operations Research and Management Science Society
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    • v.5 no.1
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    • pp.31-38
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    • 1980
  • The purpose of this paper is to exhibit existing replacement models and to develop new replacement models for managing equipments in large organizations, private or public. Some of the models in this paper are well known and in use, and some are not. All these models are classified, depending on main factors which play key roles on the models. One group is the models in which the economic factor plays a key role, and the other is those in which both the economic factor and the effectiveness factor play key roles.

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Hepatitis B Virus DNA Polymerase Displays an Anti-Apoptotic Effect by Interacting with Elongation Factor-1 Alpha-2 in Hepatoma Cells

  • Niu, Xianli;Nong, Shirong;Gong, Junyuan;Zhang, Xin;Tang, Hui;Zhou, Tianhong;Li, Wei
    • Journal of Microbiology and Biotechnology
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    • v.31 no.1
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    • pp.16-24
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    • 2021
  • Hepatitis B virus (HBV) genome P-encoded protein HBV DNA polymerase (Pol) has long been known as a reverse transcriptase during HBV replication. In this study, we investigated the impact of HBV Pol on host cellular processes, mainly apoptosis, and the underlying mechanisms. We showed a marked reduction in apoptotic rates in the HBV Pol-expressed HepG2 cells compared to controls. Moreover, a series of assays, i.e., yeast two-hybrid, GST pull-down, co-immunoprecipitation, and confocal laser scanning microscopy, identified the host factor eEF1A2 to be associated with HBV Pol. Furthermore, knockdown of eEF1A2 gene by siRNA abrogated the HBV Pol-mediated anti-apoptotic effect with apoptosis induced by endoplasmatic reticulum (ER) stress-inducer thapsigargin (TG), thus suggesting that the host factor eEF1A2 is essential for HBV Pol's anti-apoptosis properties. Our findings have revealed a novel role for HBV Pol in its modulation of apoptosis through integrating with eEF1A2.

Two-factor Authenticated and Key Exchange(TAKE) Protocol in Public Wireless LANs (공중 무선랜에서의 이중요소 인증된 키교환 프로토콜)

  • 박영만;박상규
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.13 no.4
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    • pp.29-36
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    • 2003
  • In this paper, we propose a new Two-factor Authentication and Key Exchange(TAKE) protocol that can be applied to low-power PDAs in Public Wireless LAMs using two factor authentication and precomputation. This protocol provides mutual authentication session key establishment, identity privacy, and practical half forward-secrecy. The only computational complexity that the client must perform is one symmetric key encryption and five hash functions during the runtime of the protocol.

Microwave Signal Spectrum Broadening System Based on Time Compression

  • Kong, Menglong;Tan, Zhongwei;Niu, Hui;Li, Hongbo;Gao, Hongpei
    • Current Optics and Photonics
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    • v.4 no.4
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    • pp.310-316
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    • 2020
  • We propose and experimentally demonstrate an all-optical radio frequency (RF) spectrum broadening system based on time compression. By utilizing the procedure of dispersion compensation values, the frequency domain is broadened by compressing the linear chirp optical pulse which has been multiplexed by the radio frequency. A detailed mathematical description elucidates that the time compression is a very preferred scheme for spectrum broadening. We also report experimental results to prove this method, magnification factor at 2.7, 8 and 11 have been tested with different dispersion values of fiber, the experimental results agree well with the theoretical results. The proposed system is flexible and the magnification factor is determined by the dispersion values, the proposed scheme is a linear system. In addition, the influence of key parameters, for instance optical bandwidth and the sideband suppression ratio (SSR), are discussed. Magnification factor 11 of the proposed system is demonstrated.

Glutamate attenuates lipopolysaccharide induced intestinal barrier injury by regulating corticotropin-releasing factor pathway in weaned pigs

  • Guo, Junjie;Liang, Tianzeng;Chen, Huifu;Li, Xiangen;Ren, Xiaorui;Wang, Xiuying;Xiao, Kan;Zhao, Jiangchao;Zhu, Huiling;Liu, Yulan
    • Animal Bioscience
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    • v.35 no.8
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    • pp.1235-1249
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    • 2022
  • Objective: The purpose of this study was to evaluate the protection of glutamate (GLU) against the impairment in intestinal barrier function induced by lipopolysaccharide (LPS) stress in weaned pigs. Methods: Twenty-four weaned pigs were divided into four treatments containing: i) non-challenged control, ii) LPS-challenged control, iii) LPS+1.0% GLU, and iv) LPS+2.0% GLU. On day 28, pigs were treated with LPS or saline. Blood samples were collected at 0, 2, and 4 h post-injection. After blood samples collection at 4 h, all pigs were slaughtered, and spleen, mesenteric lymph nodes, liver and intestinal samples were obtained. Results: Dietary GLU supplementation inhibited the LPS-induced oxidative stress in pigs, as demonstrated by reduced malondialdehyde level and increased glutathione level in jejunum. Diets supplemented with GLU enhanced villus height, villus height/crypt depth and claudin-1 expression, attenuated intestinal histology and ultrastructure impairment induced by LPS. Moreover, GLU supplementation reversed intestinal intraepithelial lymphocyte number decrease and mast cell number increase induced by LPS stress. GLU reduced serum cortisol concentration at 4 h after LPS stress and downregulated the mRNA expression of intestinal corticotropin-releasing factor signal (corticotrophin-releasing factor [CRF], CRF receptor 1 [CRFR1], glucocorticoid receptor, tryptase, nerve growth factor, tyrosine kinase receptor A), and prevented mast cell activation. GLU upregulated the mRNA expression of intestinal transforming growth factor β. Conclusion: These findings indicate that GLU attenuates LPS-induced intestinal mucosal barrier injury, which is associated with modulating CRF signaling pathway.

Design of Keyword Extraction System Using TFIDF (TFIDF를 이용한 키워드 추출 시스템 설계)

  • 이말례;배환국
    • Korean Journal of Cognitive Science
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    • v.13 no.1
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    • pp.1-11
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    • 2002
  • In this paper, a test was performed to determine whether words in Anchor Text were appropriate as key words. As a result of the test. there were proper words of high weighting factor, while some others did not even appear in the text. therefore, were not appropriate as key words. In order to resolve this problem. a new method was proposed to extract key words. Using the proposed method, inappropriate key words can be removed so that new key words be set, and then, ranking becomes possible with the TFIDF value as a weighting factor of the key word. It was verified that the new method has higher accuracy compared to the previous methods.

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A Study on Analyzing Effect of Claim Factoy to Prevent Claim in Early Stage for Construction Project - Focusing on Turn-Key Project - (건설 프로젝트 초기단계에서의 클레임 방지를 위한 클레임 요인 영향도 분석에 관한 연구 - 턴키공사 사레 중심으로 -)

  • Yoon Jun-Seon;Seo Choon-Taek
    • Journal of Arbitration Studies
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    • v.15 no.1
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    • pp.95-112
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    • 2005
  • In the inner turn key constructions the problems of uniform types are repeatedly occurred, and, especially, many problems happen up to the stage of pre-construction(from a bid to a contract) owing to the specialties of the turn key constructions. So the claim factors of the Korean turn key constructions were abstracted in antecedent paper. When the technicians meeting the interior turn key constructions for the first time and working here now are well acquainted with only these factors, many claims will be prevented. By analysing the degree of claims by claims factors through the questionnaires to the experts about the abstracted factors and surveying the amount of the claims through the case studies, what factors exerted how much of influence on the claims was tested and analyzed. Studying and Managing the factors affecting the claims much led the technicians in charge of internal turn key constructions to the prevention and the proper solution of the site claims.

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