• Title/Summary/Keyword: Evolution cycle

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Emergency Management on Internet Spread of Social Events

  • Dai, Weihui;Wang, Chunshi;Zhang, Yuan
    • Journal of Information Technology Applications and Management
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    • v.18 no.1
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    • pp.41-53
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    • 2011
  • The rapid development and widespread application of Internet has provided a platform for people to participate and discuss social hotspot events. In the meantime, social events may be spread throughout the Internet more quickly and widely than they did ever before, and possibly lead to serious social problems due to opinion violence or seditious rumour. This paper analyzed the Internet spread of social events, and presented a five-stage model to describe the evolution process of that spread. Furthermore, the improved IBF algorithm was applied to extract a pruned connected graph aiming to find the key nodes and the shortest spread path for the control of that spread. After analyzing the different factors that may cause the netizens' attention, this paper concluded BBS type, the visit quantity and the opinion leader are key factors which affect the Internet spread. Based on those researches, a life-cycle emergency management methodology and the related strategies were proposed for the achievement of healthy spreading environment on Internet.

Plastic energy approach prediction of fatigue crack growth

  • Maachou, Sofiane;Boulenouar, Abdelkader;Benguediab, Mohamed;Mazari, Mohamed;Ranganathan, Narayanaswami
    • Structural Engineering and Mechanics
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    • v.59 no.5
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    • pp.885-899
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    • 2016
  • The energy-based approach to predict the fatigue crack growth behavior under constant and variable amplitude loading (VAL) of the aluminum alloy 2024 T351 has been investigated and detailed analyses discussed. Firstly, the plastic strain energy was determined per cycle for different block load tests. The relationship between the crack advance and hysteretic energy dissipated per block can be represented by a power law. Then, an analytical model to estimate the lifetime for each spectrum is proposed. The results obtained are compared with the experimentally measured results and the models proposed by Klingbeil's model and Tracey's model. The evolution of the hysteretic energy dissipated per block is shown similar with that observed under constant amplitude loading.

First Finding of a Bivalve-Inhabiting Hydrozoan (Cnidaria, Hydrozoa) from Korea

  • Kubota, Shin;Lee, Jimin;Chang, Cheon Young
    • Animal Systematics, Evolution and Diversity
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    • v.35 no.2
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    • pp.57-62
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    • 2019
  • Eutima japonica Uchida, 1925, a bivalve-inhabiting hydrozoan was collected for the first time in Korea, associating with Mytilus galloprovincialis. The morphology of male medusae of this hydrozoan is clarified by culture and described as well as other developmental stages. As the present material from Korea is in good accord with that of the northern Japanese form of E. japonica, so the geographical distribution of the northern form of this species is widened, Japan, China and Korea. Green fluorescent protein distribution pattern of this medusa is also described and compared with that of the most related species Eutima sapinhoa Narchi and Hebling, 1975.

User Review Mining: An Approach for Software Requirements Evolution

  • Lee, Jee Young
    • International journal of advanced smart convergence
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    • v.9 no.4
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    • pp.124-131
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    • 2020
  • As users of internet-based software applications increase, functional and non-functional problems for software applications are quickly exposed to user reviews. These user reviews are an important source of information for software improvement. User review mining has become an important topic of intelligent software engineering. This study proposes a user review mining method for software improvement. User review data collected by crawling on the app review page is analyzed to check user satisfaction. It analyzes the sentiment of positive and negative that users feel with a machine learning method. And it analyzes user requirement issues through topic analysis based on structural topic modeling. The user review mining process proposed in this study conducted a case study with the a non-face-to-face video conferencing app. Software improvement through user review mining contributes to the user lock-in effect and extending the life cycle of the software. The results of this study will contribute to providing insight on improvement not only for developers, but also for service operators and marketing.

Expanding roles of centrosome abnormalities in cancers

  • Soohyun Song;Surim Jung;Mijung Kwon
    • BMB Reports
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    • v.56 no.4
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    • pp.216-224
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    • 2023
  • Centrosome abnormalities are hallmarks of human cancers. Structural and numerical centrosome abnormalities correlate with tumor aggressiveness and poor prognosis, implicating that centrosome abnormalities could be a cause of tumorigenesis. Since Boveri made his pioneering recognition of the potential causal link between centrosome abnormalities and cancer more than a century ago, there has been significant progress in the field. Here, we review recent advances in the understanding of the causes and consequences of centrosome abnormalities and their connection to cancers. Centrosome abnormalities can drive the initiation and progression of cancers in multiple ways. For example, they can generate chromosome instability through abnormal mitosis, accelerating cancer genome evolution. Remarkably, it is becoming clear that the mechanisms by which centrosome abnormalities promote several steps of tumorigenesis are far beyond what Boveri had initially envisioned. We highlight various cancer-promoting mechanisms exerted by cells with centrosome abnormalities and how these cells possessing oncogenic potential can be monitored.

Numerical Simulations of Nonlinear Behaviors of Pulsating Instabilities in Counterflow Diffusion Flames (대향류 확산화염에서 맥동 불안정성의 비선형 거동에 대한 수치해석)

  • Lee, Su-Ryong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.9
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    • pp.859-866
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    • 2010
  • Nonlinear dynamics of pulsating instability-diffusional-thermal instability with Lewis numbers sufficiently higher than unity-in counterflow diffusion flames, is numerically investigated by imposing a Damkohler number perturbation. The flame evolution exhibits three types of nonlinear behaviors, namely, decaying pulsating behavior, diverging behavior (which leads to extinction), and stable limit-cycle behavior. The stable limit-cycle behavior is observed in counterflow diffusion flames, but not in diffusion flames with a stagnant mixing layer. The critical value of the perturbed Damkohler number, which indicates the region where the three different flame behaviors can be observed, is obtained. A stable simple limit cycle, in which two supercritical Hopf bifurcations exist, is found in a narrow range of Damkohler numbers. As the flame temperature is increased, the stable simple limit cycle disappears and an unstable limit cycle corresponding to subcritical Hopf bifurcation appears. The period-doubling bifurcation is found to occur in a certain range of Damkohler numbers and temperatures, which leads to extend the lower boundary of supercritical Hopf bifurcation.

Effect of Leaf Temperature on Light Response and Respiration in Panax ginseng C. A. Meyer (고려인삼에서 광반응 및 호흡에 미치는 잎온도의 영향)

  • 현동윤;유남희
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.6
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    • pp.725-728
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    • 1996
  • This study was conducted to investigate effect of leaf temperature on light response and respiration during short-term exposure to a sequnce of PPFD cycle(100-200-300-400$\mu$ mol m$^{-2}$ s$^{-1}$ ) under increasing leaf temperature sequnce up to 3$0^{\circ}C$ and in dark condition, increasing up to 46$^{\circ}C$ with step size (1$^{\circ}C$) in Panax ginseng C. A. Meyer. When leaflet exposed to low light intensity and temperature, Rubisco activity was higher than remained activity in high condition. Leaves adapted to 100$\mu$mol m$^{-2}$ s$^{-1}$ PPFD had a peak response similar to that of 200$\mu$mol m$^{-2}$ s$^{-1}$ at 18$^{\circ}C$, but in above PPFD cycle(300, 400$\mu$mol m$^{-2}$ s$^{-1}$ ) it represented at 17$^{\circ}C$ and 16$^{\circ}C$, re-spectively. $CO_2$ evolution in dark condition increased rapidly when leaf temperature was increased up to 28$^{\circ}C$ and then 'dipped' below steady-state level from above 4$0^{\circ}C$. Thus, Pananx ginseng is able to take advantage of irradiance increase and decrease of $CO_2$ evolution in dark condition to control leaf temperature.mperature.

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Improved Cycle Life and Storage Performance in High-Voltage Operated Li2MnO3-LiMO2(M=Ni, Co, Mn)/Graphite Cell System by Fluorine Compounds as Main Electrolyte Solvent (고전압 구동 Li2MnO3-LiMO2(M=Ni, Co, Mn)/graphite 시스템에서의 전지 수명 및 고온 방치 특성 향상에 효과적인 플루오로 화합물계 전해액에 대한 연구)

  • Yu, Jung-Yi;Shin, Woocheol;Lee, Byong-Gon
    • Journal of the Korean Electrochemical Society
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    • v.16 no.3
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    • pp.162-168
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    • 2013
  • $Li_2MnO_3-LiMO_2$(M=Ni, Co, Mn) nano-composite is a promising cathode material for xEV application due to its high theoretic capacity. However high voltage operating system of $Li_2MnO_3-LiMO_2$(M=Ni, Co, Mn) has worked as a hurdle in its application because of the inherent demerits, such as cycle life degradation and gas evolution. In order to enhance cell performance of $Li_2MnO_3-LiMO_2$(M=Ni, Co, Mn)/graphite cell, we examined electrolyte mainly composed of FEC, fluroalkyl ether and $LiPF_6$ (F-based EL). F-based EL showed much better discharging retention ratio than 1.3 M $LiPF_6$ EC/EMC/DMC (3/4/3, v/v/v) (STD). Furthermore gas evolution, especially CO and $CO_2$ during $60^{\circ}C$ storage for 30 days was dramatically reduced owing to thermal stable SEI formation effect of F-based EL.

LIFECYCLE OF THE INTERSTELLAR DUST GRAINS IN OUR GALAXY VIEWED WITH AKARI/MIR ALL-SKY SURVEY

  • Ishihara, D.;Kaneda, H.;Mouri, A.;Kondo, T.;Suzuki, S.;Oyabu, S.;Onaka, T.;Ita, Y.;Matsuura, M.;Matsunaga, N.
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.117-122
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    • 2012
  • The interstellar dust grains are formed and supplied to interstellar space from asymptotic giant branch (AGB) stars or supernova remnants, and become constituents of the star- and planet-formation processes that lead to the next generation of stars. Both a qualitative, and a compositional study of this cycle are essential to understanding the origin of the pre-solar grains, the missing sources of the interstellar material, and the chemical evolution of our Galaxy. The AKARI/MIR all-sky survey was performed with two mid-infrared photometric bands centered at 9 and $18{\mu}m$. These data have advantages in detecting carbonaceous and silicate circumstellar dust of AGB stars, and the interstellar polycyclic aromatic hydrocarbons separately from large grains of amorphous silicate. By using the AKARI/MIR All-Sky point source catalogue, we surveyed C-rich and O-rich AGB stars in our Galaxy, which are the dominant suppliers of carbonaceous and silicate grains, respectively. The C-rich stars are uniformly distributed across the Galactic disk, whereas O-rich stars are concentrated toward the Galactic center, following the metallicity gradient of the interstellar medium, and are presumably affected by the environment of their birth place. We will compare the distributions of the dust suppliers with the distributions of the interstellar grains themselves by using the AKARI/MIR All-Sky diffuse maps. To enable discussions on the faint diffuse interstellar radiation, we are developing an accurate AKARI/MIR All-Sky diffuse map by correcting artifacts such as the ionising radiation effects, scattered light from the moon, and stray light from bright sources.

Experimental investigations on detecting lateral buckling for subsea pipelines with distributed fiber optic sensors

  • Feng, Xin;Wu, Wenjing;Li, Xingyu;Zhang, Xiaowei;Zhou, Jing
    • Smart Structures and Systems
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    • v.15 no.2
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    • pp.245-258
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    • 2015
  • A methodology based on distributed fiber optic sensors is proposed to detect the lateral buckling for subsea pipelines in this study. Uncontrolled buckling may lead to serious consequences for the structural integrity of a pipeline. A simple solution to this problem is to control the formation of lateral buckles among the pipeline. This firms the importance of monitoring the occurrence and evolution of pipeline buckling during the installation stage and long-term service cycle. This study reports the experimental investigations on a method for distributed detection of lateral buckling in subsea pipelines with Brillouin fiber optic sensor. The sensing scheme possesses the capability for monitoring the pipeline over the entire structure. The longitudinal strains are monitored by mounting the Brillouin optical time domain analysis (BOTDA) distributed sensors on the outer surface of the pipeline. Then the bending-induced strain is extracted to detect the occurrence and evolution of lateral buckling. Feasibility of the method was validated by using an experimental program on a small scale model pipe. The results demonstrate that the proposed approach is able to detect, in a distributed manner, the onset and progress of lateral buckling in pipelines. The methodology developed in this study provides a promising tool for assessing the structural integrity of subsea pipelines.