• Title/Summary/Keyword: mass uncertainty

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Impact of Internet Media Reports on the COVID-19 Pandemic in the Population Aged 20-35

  • Stytsyuk, Rita Yurievna;Panova, Alexandra Georgievna;Zenin, Sergey;Kvon, Daniil Andreevich;Gorokhova, Anna Evgenievna;Ulyanishchev, Pavel Viktorovich
    • International Journal of Computer Science & Network Security
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    • v.22 no.6
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    • pp.39-44
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    • 2022
  • The advent, course, and possible consequences of the COVID-19 pandemic are now the focus of global attention. From whichever side the geopolitical centers of influence might view it, the problem of the coronavirus concerns all world leaders and the representatives of all branches of science, especially physicians, economists, and politicians - virtually the entire population of the planet. The uniqueness of the COVID-19 phenomenon lies in the uncertainty of the problem itself, the peculiarities and specifics of the course of the biological processes in modern conditions, as well as the sharp confrontation of the main political players on the world stage. Based on an analysis of scientific research, the article describes the profile of the emotional concept of "anxiety" in Russian linguoculture. Through monitoring the headlines of Russian media reports in the "COVID-19" section of Google News and Mail News news aggregators dated August 4-6, 2021, the study establishes the quantitative and qualitative characteristics of the alarm-generating news products on coronavirus in the Russian segment of the Internet and interprets the specifics of media information about COVID-19. The level of mass media criticism in Russia is determined through a phone survey. It is concluded that coronavirus reports in online media conceptualize anxiety about the SARS virus and the COVID-19 disease as a complex cognitive structure. The media abuse the trick of "magic numbers" and emotionally expressive words in news headlines, which are perceived by mass information consumers first and typically uncritically.

Development of a predictive functional control approach for steel building structure under earthquake excitations

  • Mohsen Azizpour;Reza Raoufi;Ehsan Kazeminezhad
    • Earthquakes and Structures
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    • v.25 no.3
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    • pp.187-198
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    • 2023
  • Model Predictive Control (MPC) is an advanced control approach that uses the current states of the system model to predict its future behavior. In this article, according to the seismic dynamics of structural systems, the Predictive Functional Control (PFC) method is used to solve the control problem. Although conventional PFC is an efficient control method, its performance may be impaired due to problems such as uncertainty in the structure of state sensors and process equations, as well as actuator saturation. Therefore, it requires the utilization of appropriate estimation algorithms in order to accurately evaluate responses and implement actuator saturation. Accordingly, an extended PFC is presented based on the H-ifinity (H∞) filter (HPFC) while considering simultaneously the saturation actuator. Accordingly, an extended PFC is presented based on the H-ifinity (H∞) filter (HPFC) while considering the saturation actuator. Thus, the structural responses are formulated by two estimation models using the H∞ filter. First, the H∞ filter estimates responses using a performance bound (𝜃). Second, the H∞ filter is converted into a Kalman filter in a special case by considering the 𝜃 equal to zero. Therefore, the scheme based on the Kalman filter (KPFC) is considered a comparative model. The proposed method is evaluated through numerical studies on a building equipped with an Active Tuned Mass Damper (ATMD) under near and far-field earthquakes. Finally, HPFC is compared with classical (CPFC) and comparative (KPFC) schemes. The results show that HPFC has an acceptable efficiency in boosting the accuracy of CPFC and KPFC approaches under earthquakes, as well as maintaining a descending trend in structural responses.

A Comparative Study on the REV, non-REV and Joint Network Methods for Analysis of Groundwater Flow in Jointed Rock Masses (절리암반내 지하수 유동해석을 위한 대표체적법, 비대표체적법 및 절리망 해석법의 비교 연구)

  • 문현구
    • Journal of the Korean Geotechnical Society
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    • v.15 no.5
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    • pp.217-228
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    • 1999
  • The three methods of analysis (i) REV(representative elemental volume), (ii) non-REV and (iii) joint network analysis are introduced in this paper to analyze the groundwater flow in jointed rock mass and the inflow into underground excavations. The results from those methods are compared one another to reveal their characteristics by varying the number of joints and the diameter of the opening. The pre-processor, the so-called sequential analysis, is introduced to predict the equivalent hydraulic conductivity of a jointed rock mass having a number of intersecting joints. Using the finite element mesh, joint map and sequential analysis, the equivalent hydraulic conductivities are calculated for all 445 elements. The hydraulic inhomogeneity and the determination of the representative properties of jointed rock masses are discussed. In the REV analysis where the entire rock mass is homogenized through the representative properties, the inflow is increased regularly and consistently by increasing the joint density, the opening size and the conductivity contrast value. Though the non-REV analysis showed irregular variation of the inflow due to the local inhomogeneity allowed to individual elements, the inflow approached the REV results as the characteristic length increases. The joint network analysis showed the most sensitive reaction to the joint density, the opening size and the presence of the network crossing the opening. The reliability of the network analysis depends on the geometric data of individual joints. In view of the limited field data on joint geometry and possible uncertainty the REV and non-REV methods are considered more practical and rational than the joint network analysis.

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Evaluation of the Standard Support Pattern in Large Section Tunnel by Numerical Analysis and Field Measurement (수치해석 및 현장계측에 의한 대단면 터널 표준지보패턴의 적정성 검증)

  • Byun, Yoseph;Chung, Sungrae;Song, Simyung;Chun, Byungsik;Park, Duhee
    • Journal of the Korean GEO-environmental Society
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    • v.12 no.7
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    • pp.5-12
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    • 2011
  • When choosing the support pattern of tunnel, the characteristics of rock are identified from the result of the surface geologic survey, boring, and geophysical prospecting and laboratory test. And a rock mass rating is classified and excavation method and standard support pattern are designed considering rock classification, domestic and international construction practices, numerical analysis. According to the revised design standard for tunnel, it was recommended to classify the rock mass rating for the design of tunnel into a rating based on RMR. If necessary, it proposed a flexible standard allowed applying more atomized the rock mass rating and Q-System. Also, the resonable verification of the support pattern must be accompanied because the factors affecting the structure and behavior of ground during the construction of tunnel are the main factors of uncertainty factors such as the nature of ground, ground water and the characteristics of structural materials. These days, such verification method is getting more specialized and diversified. In this study, the empirical method, numerical analysis and comparative analysis of in situ measurements were used to prove the reasonableness in the support pattern by RMR and Q-value on the Imha Dam emergency spillway.

Development of a Noble Gas Isotope Dilution Mass Spectrometric System Combined with a Cryogenic Cold Trap (초저온 냉각 트랩을 결합한 비활성기체 동위원소 희석 질량분석 시스템의 제작)

  • HONG, BONGJAE;SHIN, DONGYOUB;PARK, KEYHONG;HAHM, DOSHIK
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.27 no.3
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    • pp.144-157
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    • 2022
  • Noble gases, which are chemically inert and behave conservatively in marine environments, have been used as tracers of physical processes such as air-sea gas exchange, mixing of water masses, and distribution of glacial meltwater in the ocean. For precise measurements of Ne, Ar, and Kr, we developed a mass spectrometric system consisting of a quadrupole mass spectrometer (QMS), a high vacuum preparation line, an activated charcoal cryogenic trap (ACC), and a set of isotope standard gases. The high vacuum line consists of three sections: (1) a sample extraction section that extracts the dissolved gases in the sample and mixes them with the standard gases, (2) a gas preparation section that removes reactive gases using getters and separates the noble gases according to their evaporation points with the ACC, and (3) a gas analysis section that measures concentrations of each noble gas. The ACC attached to the gas preparation section markedly lowered the partial pressures of Ar and CO2 in the QMS, which resulted in a reduced uncertainty of Ne isotope analysis. The isotope standard gases were prepared by mixing 22Ne, 36Ar, and 86Kr. The amounts of each element in the mixed standard gases were determined by the reverse isotope dilution method with repeated measurements of the atmosphere. The analytical system achieved precisions for Ne, Ar, and Kr concentrations of 0.7%, 0.7%, and 0.4%, respectively. The accuracies confirmed by the analyses of air-equilibrated water were 0.5%, 1.0%, and 1.7% for Ne, Ar, and Kr, respectively.

Environmental Dependence of Galactic conformity in the Virgo Cluster

  • Lee, Hye-Ran;Lee, Joon Hyeop;Jeong, Hyunjin;Park, Byeong-Gon
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.77.3-78
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    • 2015
  • It is known that the galaxy evolution by direct interaction between galaxies is most active in a galaxy group. As a result, the satellite galaxies are closely related to their central galaxy in properties such as morphology, color and star formation rate (so-called 'galactic conformity'). However, it is not clear yet whether such conformity between galaxies is found in a galaxy cluster. Recently, Lee et al. (2014) have found a measurable correlation between the colors of bright galaxies and the mean colors of their faint companions in a cluster WHL J085910.0+294957 at z = 0.3, using the photometrically-selected cluster members. They suggest that such correlation may be the vestige of infallen groups in the cluster as one possibility. In order to confirm the small-scale conformity in galaxy clusters with higher reliability, we study the Virgo cluster using the Extended Virgo Cluster Catalog (EVCC). The cluster members are selected spectroscopically unlike in WHL J085910.0+294957. We examine the galactic conformity in two distinct areas of the Virgo cluster: the inner X-ray emission region and its outer region. We find a marginal conformity in color (> $2{\sigma}$ significance to bootstrap uncertainty) in the outer region, while no meaningful signal of small-scale conformity is detected in the X-ray emission region. We discuss the implication of this result, focusing on cluster mass assembly and cluster environmental effects on galaxy evolution.

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The Conditions of the Entrepreneurial Laver Culture (기업적 해태양식경영의 성립조건에 관한 연구)

  • 김연수
    • The Journal of Fisheries Business Administration
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    • v.15 no.1
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    • pp.96-113
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    • 1984
  • It has been appeared since 1979 that the pattern of laver culture changes from household management to entrepreneurial management. The typical entrepreneurial laver culture management (ELCM) can be defined as a management by the floating aquaculturing method and mechanical processing system. Historical studies show that the ELCM could be operated only under the following condintions; \circled1 securing capital, labor and aquaculturing farm. \circled2 Leveling up of technology to combine these resources effectively. \circled3 Realizing its true value of products for good profits. In turning from household mangement to ELCM, there are some obstacles as follows ; \circled1 Uncertainty, which cannot maintein the merit of mass production because the object of laver culture is living in the sea. \circled2 Immaturity of management owing manly to the lower level of technology and scarcity of competent managers. \circled3 Social problems ; lack of aquaculturing farm, overpopulation in fishing villiage, side-job with agriculture etc. For these reasons, there has been household management with overlabor and underconsumption in fishing village. In order that ELCM can enter the stage of maturity, those problems should be solved. Because ef laver industrial inferiority, these can be solved by the support assistance of government. As the required conditions in ELCM are filled by the government policy, ELCM are increased recently in its numbers.

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Identification and Robust $H_\infty$ Control of the Rotational/Translational Actuator System

  • Tavakoli Mahdi;Taghirad Hamid D.;Abrishamchian Mehdi
    • International Journal of Control, Automation, and Systems
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    • v.3 no.3
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    • pp.387-396
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    • 2005
  • The Rotational/Translational Actuator (RTAC) benchmark problem considers a fourth-order dynamical system involving the nonlinear interaction of a translational oscillator and an eccentric rotational proof mass. This problem has been posed to investigate the utility of a rotational actuator for stabilizing translational motion. In order to experimentally implement any of the model-based controllers proposed in the literature, the values of model parameters are required which are generally difficult to determine rigorously. In this paper, an approach to the least-squares estimation of the parameters of a system is formulated and practically applied to the RTAC system. On the other hand, this paper shows how to model a nonlinear system as a linear uncertain system via nonparametric system identification, in order to provide the information required for linear robust $H_\infty$ control design. This method is also applied to the RTAC system, which demonstrates severe nonlinearities, due to the coupling from the rotational motion to the translational motion. Experimental results confirm that this approach can effectively condense the whole nonlinearities, uncertainties, and disturbances within the system into a favorable perturbation block.

A Study on The Process of Design Idea - Focused on An Expansion and A Diversity of Idea (디자인 아이디어 전개에 관한 연구 - 사고의 확장성과 다의성을 중심으로)

  • 이한성
    • Archives of design research
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    • v.17 no.2
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    • pp.67-76
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    • 2004
  • The main stream of consumption about the products is tend to transfer from low price value with mass production, to the second value of products, such as pleasure, familiarity, humor, and metaphor. This second value is closely connected to a redundancy which are also related to modern science as well as product design. These terms such as matrials, identity, and gravitation, disappeared gradually, and these are substituted with an uncertainty principle, a fortuity, a contradictory concept, entropy etc. In sum this study focuses on the tendency of intelligency issue the recent design trends. This result shows that The 4th Column Thinking and Formation System which is related to an expansion and diversity of design intellectual ideas.

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An Estimation of Modeling Uncertainty for a Mechanical System in Actuators and Links in a Rigid Manipulator Using Control Theory (시스템 모델링의 불확실성 추정과 보상)

  • Park, Rai-Wung;Cho, Sul
    • 대한공업교육학회지
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    • v.34 no.2
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    • pp.396-410
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    • 2009
  • The goal of this work is to present an advanced method of an estimation of the Modeling Uncertainties coming up in industrial rigid robot's manipulator and actuators. First, with the given physical robot model, the motion equation was derived. Considering a fictitious model, a new extended motion equation is developed. Based on this extended model, an observer and observer bank are designed for the estimation of modeling uncertainties which are involving the effects of gravity, friction, mass unbalance, and Coriolis which show the nonlinear characteristics in operation states.