scholarly journals Prediction of the VIV Responses Based on the Numerical Solutions of Controlled Motion

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Duanmu Yu ◽  
Chen Jianping ◽  
Chen Yizhong
Keyword(s):  
Free Vibration ◽  
Prediction Model ◽  
Numerical Solutions ◽  
Phase Relationship ◽  
Forced Oscillations ◽  
Flow Solver ◽  
Temporal Phase ◽  
Wide Range ◽  
The Relationship ◽  
Internal Relationship

The study of forced and free vibration of a cylinder has long been isolated. The internal relationship between free vibration and forced vibration has rarely been investigated. In this paper, the relationship between the forced and free vibration of a cylinder was established. A series of numerical simulations of a cylinder undergoing forced oscillations at a wide range of vibration amplitudes and frequencies were carried out, with the flow solver viv-FOAM-SJTU developed based on the open-source platform OpenFOAM. Complex demodulation analysis was conducted to quantify the spatial-temporal phase relationship between the forces and the displacement of the cylinder. It was found that, at some particular oscillating amplitudes and frequencies, the phase angle switched between positive and negative values, which corresponds to a vortex mode transferring from the 2P mode to the 2 P O mode. This distinct new mode “ 2 P O ” was closely related to the intermittent jumping between lower and upper branches of the amplitude responses of VIV. A prediction model was developed to obtain the VIV amplitude responses based on the numerical results of forced oscillation. The prediction results of three points located separately in the initial, upper, and lower branches of VIV agreed well with experimental measurements of an elastically mounted cylinder. This prediction model was thus expected to be suitable for predicting the response of VIV.

A New Static Analysis Approach for Free Vibration of Beams

2018 ◽  
Vol 10 (01) ◽  
pp. 1850004 ◽  
Author(s):  
C. W. Lim ◽  
Zhenyu Chen
Keyword(s):  
Free Vibration ◽  
Static Analysis ◽  
Vibration Analysis ◽  
Natural Frequencies ◽  
Numerical Solutions ◽  
Free Vibration Analysis ◽  
Concentrated Force ◽  
Static Approach ◽  
Beam Bending ◽  
The Relationship

This study deals with a new method for the free vibration analysis of beams under different boundary conditions. We show that it is possible to apply a static approach for solving free vibration systems, i.e., we obtain natural frequencies for free vibration of beams by analyzing static beam bending problems. Specifically, the basic governing equation for beams with harmonic loadings and resting on an elastic foundation is solved and the solutions are used directly to yield the beam free vibration solutions. In the free vibration analysis, the natural frequency can be a real number or an imaginary number while in the static analysis, the foundation stiffness can be either positive or negative. We show that one can solve the deflection of a beam subjected to a given concentrated force and subsequently deduce the possible infinite deflection when the stiffness becomes zero or negative. In such cases, there exists an equivalent relationship between the free vibration frequencies and the negative stiffness. Consequently, determining the natural frequencies becomes a problem of determining an appropriate negative foundation elastic constant. In general, the numerical vibration solutions can be obtained by analyzing the relationship between loadings and frequencies. For comparison, a comparison with the classical free vibration solutions is presented and excellent agreement is illustrated. We further show that this static approach for free vibration solutions has a clear edge over the classical free vibration approach in computational beam vibration solutions. Very accurate and convergent numerical solutions can be obtained using a very simple numerical solution method. This static approach for free vibration problems can be extended for plate, shell and other structural systems.

The Problem of Identifying and Modeling the Relationship between Monetary Factor and Inflation in the Russian Economy

2008 ◽  
pp. 61-76
Author(s):  
A. Porshakov ◽  
A. Ponomarenko
Keyword(s):  
Money Supply ◽  
Money Demand ◽  
Russian Economy ◽  
Long Run ◽  
Complex Approach ◽  
Wide Range ◽  
Long Time ◽  
The Relationship ◽  
Supply Side Factors

The role of monetary factor in generating inflationary processes in Russia has stimulated various debates in social and scientific circles for a relatively long time. The authors show that identification of the specificity of relationship between money and inflation requires a complex approach based on statistical modeling and involving a wide range of indicators relevant for the price changes in the economy. As a result a model of inflation for Russia implying the decomposition of inflation dynamics into demand-side and supply-side factors is suggested. The main conclusion drawn is that during the recent years the volume of inflationary pressures in the Russian economy has been determined by the deviation of money supply from money demand, rather than by money supply alone. At the same time, monetary factor has a long-run spread over time impact on inflation.

scholarly journals Effects of Precast Cladding Systems on Dynamic Characteristics of Steel Frame Buildings by Ambient and Free Vibration Tests

2017 ◽  
Vol 2017 ◽  
pp. 1-20 ◽  
Author(s):  
Jun Ma ◽  
Shinji Nakata ◽  
Akihito Yoshida ◽  
Yukio Tamura
Keyword(s):  
Free Vibration ◽  
Dynamic Characteristics ◽  
Steel Frame ◽  
Ambient Vibration ◽  
Test Cases ◽  
Vibration Method ◽  
External Wall ◽  
Wide Range ◽  
Cladding Panels ◽  
Vibration Tests

Full-scale tests on a one-story steel frame structure with a typical precast cladding system using ambient and free vibration methods are described in detail. The cladding system is primarily composed of ALC (Autoclaved Lightweight Concrete) external wall cladding panels, gypsum plasterboard interior linings, and window glazing systems. Ten test cases including the bare steel frame and the steel frame with addition of different parts of the precast cladding system are prepared for detailed investigations. The amplitude-dependent dynamic characteristics of the test cases including natural frequencies and damping ratios determined from the tests are presented. The effects of the ALC external wall cladding panels, the gypsum plasterboard interior linings, and the window glazing systems on the stiffness and structural damping of the steel frame are discussed in detail. The effect of the precast cladding systems on the amplitude dependency of the dynamic characteristics and the tendencies of the dynamic parameters with respect to the structural response amplitude are investigated over a wide range. Furthermore, results estimated from the ambient vibration method are compared with those from the free vibration tests to evaluate the feasibility of the ambient vibration method.

scholarly journals Polymorphic Iterable Sequential Effect Systems

2021 ◽  
Vol 43 (1) ◽  
pp. 1-79
Author(s):  
Colin S. Gordon
Keyword(s):  
Algebraic Structure ◽  
Position Effect ◽  
Type Systems ◽  
Sequential Effect ◽  
Prior Work ◽  
Sequential Effects ◽  
Wide Range ◽  
The Relationship ◽  
Categorical Semantics

Effect systems are lightweight extensions to type systems that can verify a wide range of important properties with modest developer burden. But our general understanding of effect systems is limited primarily to systems where the order of effects is irrelevant. Understanding such systems in terms of a semilattice of effects grounds understanding of the essential issues and provides guidance when designing new effect systems. By contrast, sequential effect systems—where the order of effects is important—lack an established algebraic structure on effects. We present an abstract polymorphic effect system parameterized by an effect quantale—an algebraic structure with well-defined properties that can model the effects of a range of existing sequential effect systems. We define effect quantales, derive useful properties, and show how they cleanly model a variety of known sequential effect systems. We show that for most effect quantales, there is an induced notion of iterating a sequential effect; that for systems we consider the derived iteration agrees with the manually designed iteration operators in prior work; and that this induced notion of iteration is as precise as possible when defined. We also position effect quantales with respect to work on categorical semantics for sequential effect systems, clarifying the distinctions between these systems and our own in the course of giving a thorough survey of these frameworks. Our derived iteration construct should generalize to these semantic structures, addressing limitations of that work. Finally, we consider the relationship between sequential effects and Kleene Algebras, where the latter may be used as instances of the former.

Age-Dependency of Total Tau in the Cerebrospinal Fluid Is Corrected by Amyloid-β 1–40: A Correlational Study in Healthy Adults

2021 ◽  
pp. 1-8
Author(s):  
Paul Theo Zebhauser ◽  
Achim Berthele ◽  
Marie-Sophie Franz ◽  
Oliver Goldhardt ◽  
Janine Diehl-Schmid ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Amyloid Β ◽  
Healthy Adults ◽  
Tau Proteins ◽  
Clinical Settings ◽  
Inclusion Criteria ◽  
Total Tau ◽  
Potential Marker ◽  
Wide Range ◽  
The Relationship

Background: Tau proteins are established biomarkers of neuroaxonal damage in a wide range of neurodegenerative conditions. Although measurement of total-Tau in the cerebrospinal fluid is widely used in research and clinical settings, the relationship between age and total-Tau in the cerebrospinal fluid is yet to be fully understood. While past studies reported a correlation between age and total-Tau in the cerebrospinal fluid of healthy adults, in clinical practice the same cut-off value is used independently of patient’s age. Objective: To further explore the relationship between age and total-Tau and to disentangle neurodegenerative from drainage-dependent effects. Methods: We analyzed cerebrospinal fluid samples of 76 carefully selected cognitively healthy adults and included amyloid-β 1–40 as a potential marker of drainage from the brain’s interstitial system. Results: We found a significant correlation of total-Tau and age, which was no longer present when correcting total-Tau for amyloid-β 1–40 concentrations. These findings were replicated under varied inclusion criteria. Conclusion: Results call into question the association of age and total-Tau in the cerebrospinal fluid. Furthermore, they suggest diagnostic utility of amyloid-β 1–40 as a possible proxy for drainage-mechanisms into the cerebrospinal fluid when interpreting biomarker concentrations for neurodegenerative diseases.

scholarly journals Modelling the elastic mechanical properties of bioactive glass-derived scaffolds

2020 ◽  
Vol 6 (1) ◽  
pp. 50-56
Author(s):  
Francesco Baino ◽  
Elisa Fiume
Keyword(s):  
Elastic Properties ◽  
Poisson’S Ratio ◽  
Mechanical Performance ◽  
Solid Material ◽  
Poisson's Ratio ◽  
Predictive Capability ◽  
Shear Moduli ◽  
Wide Range ◽  
Constitutive Parameters ◽  
The Relationship

AbstractPorosity is known to play a pivotal role in dictating the functional properties of biomedical scaffolds, with special reference to mechanical performance. While compressive strength is relatively easy to be experimentally assessed even for brittle ceramic and glass foams, elastic properties are much more difficult to be reliably estimated. Therefore, describing and, hence, predicting the relationship between porosity and elastic properties based only on the constitutive parameters of the solid material is still a challenge. In this work, we quantitatively compare the predictive capability of a set of different models in describing, over a wide range of porosity, the elastic modulus (7 models), shear modulus (3 models) and Poisson’s ratio (7 models) of bioactive silicate glass-derived scaffolds produced by foam replication. For these types of biomedical materials, the porosity dependence of elastic and shear moduli follows a second-order power-law approximation, whereas the relationship between porosity and Poisson’s ratio is well fitted by a linear equation.

A Progressive View on Religion and Modern Art

2015 ◽  
Vol 19 (5) ◽  
pp. 488-530
Author(s):  
Cynthia Fowler
Keyword(s):  
Cultural Identity ◽  
Modern Art ◽  
Religious Art ◽  
Wide Range ◽  
Museum Professionals ◽  
The Relationship

This article examines the Religious Art of Today exhibition, originally held in 1944 at Boston’s Institute of Modern Art and then reformulated for the Dayton Art Institute in Ohio. The exhibition was eclectic in that it included a wide range of artists and a diversity of faiths, and engaged the debate held among museum professionals about the relationship between religion and modern art. The article focuses closely on Catholic, Jewish, and Navajo art included in the exhibition. The IMA’s commitment to the figurative tradition afforded artists the opportunity to explore their identities—as Jews, as Catholics, as Navajos—using recognizable religious subjects. That the works in the exhibition were selected as representative of modern art resulted in a convergence of discourses related to modern art with those of religious/cultural identity.

scholarly journals New Insights into Molecular Mechanism behind Anti-Cancer Activities of Lycopene

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3888
Author(s):  
Boon-Peng Puah ◽  
Juriyati Jalil ◽  
Ali Attiq ◽  
Yusof Kamisah
Keyword(s):  
Immune Cells ◽  
Scientific Evidence ◽  
Special Role ◽  
Real Potential ◽  
Wide Range ◽  
Anti Cancer ◽  
The Family ◽  
The Relationship ◽  
Cancer Activity ◽  
Reduced Risk

Lycopene is a well-known compound found commonly in tomatoes which brings wide range of health benefits against cardiovascular diseases and cancers. From an anti-cancer perspective, lycopene is often associated with reduced risk of prostate cancer and people often look for it as a dietary supplement which may help to prevent cancer. Previous scientific evidence exhibited that the anti-cancer activity of lycopene relies on its ability to suppress oncogene expressions and induce proapoptotic pathways. To further explore the real potential of lycopene in cancer prevention, this review discusses the new insights and perspectives on the anti-cancer activities of lycopene which could help to drive new direction for research. The relationship between inflammation and cancer is being highlighted, whereby lycopene suppresses cancer via resolution of inflammation are also discussed herein. The immune system was found to be a part of the anti-cancer system of lycopene as it modulates immune cells to suppress tumor growth and progression. Lycopene, which is under the family of carotenoids, was found to play special role in suppressing lung cancer.

scholarly journals Exploring the Relationship between Sustainable Projects and Institutional Isomorphisms: A Project Typology

2020 ◽  
Vol 12 (9) ◽  
pp. 3668 ◽  
Author(s):  
Rakan Alyamani ◽  
Suzanna Long ◽  
Mohammad Nurunnabi
Keyword(s):  
Information Exchange ◽  
External Factors ◽  
Energy Sources ◽  
Management Research ◽  
Experience Levels ◽  
Wide Range ◽  
Institutional Influences ◽  
Change Level ◽  
The Relationship ◽  
Sustainable Projects

With the increase in awareness about the wide range of issues and adverse effects associated with the use of conventional energy sources came an increase in project management research related to sustainability and sustainable development. Part of that research is devoted to the development of sustainable project typologies that classify projects based on a variety of external factors that can significantly impact these projects. This research focuses on developing a sustainable project typology that classifies sustainable projects based on the external institutional influences. The typology explores the influence of the coercive, normative, and mimetic institutional isomorphisms on the expected level of change, level of uncertainty, project team skills and experience levels, and the level of technology information exchange in sustainable projects. Two case studies are presented to demonstrate the use of the typology to classify sustainable projects based on the external institutional influences.

scholarly journals TARGET MODAL SPLIT MODEL

Transport ◽  
2012 ◽  
Vol 26 (4) ◽  
pp. 418-424 ◽  
Author(s):  
Valentina Basarić ◽  
Jadranka Jović
Keyword(s):  
Public Transport ◽  
Stepwise Regression ◽  
Statistical Data ◽  
Transport Policy ◽  
Wide Range ◽  
Policy Measures ◽  
Novi Sad ◽  
The Relationship ◽  
The City ◽  
Statistical Results

The research presented in this paper is aimed at defining a model that enables the management of the relationship between private vehicles and public transport applying the available instruments of city transport policy such as parking policy and public transport policy measures. Statistical data used for modelling is sourced from the database in a wide range of EU cities. The target model was developed in the form of stepwise regression analysis. Very favourable statistical results were obtained, and the subsequent tests on the city of Novi Sad (250000 inhabitants) led to the conclusion that the obtained results were suitable for implementation in practice. The results of the implemented procedure are of great importance for the enhancement of the existing transport policies in cities, as they enable the development of strategies for finding combinations of instruments that would bring the transport system and urban environment into a desired-viable rather than consequential condition.

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