Статті в журналах з теми "Rate-dependent evolution"

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1

Bachmaier, Andrea, Martin Hafok, and Reinhard Pippan. "Rate Independent and Rate Dependent Structural Evolution during Severe Plastic Deformation." MATERIALS TRANSACTIONS 51, no. 1 (2010): 8–13. http://dx.doi.org/10.2320/matertrans.mb200912.

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2

Jia, Zheng, and Wing Kam Liu. "Rate-dependent stress evolution in nanostructured Si anodes upon lithiation." Applied Physics Letters 109, no. 16 (October 17, 2016): 163903. http://dx.doi.org/10.1063/1.4964515.

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3

Lienhard, J., D. Discher, and J. Hohe. "Strain rate dependent damage evolution in long glass fiber reinforced polypropylene." Composites Science and Technology 189 (March 2020): 108007. http://dx.doi.org/10.1016/j.compscitech.2020.108007.

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4

Nadler, Ben. "Isotropic rate-dependent finite plasticity using the theory of material evolution." Acta Mechanica 223, no. 11 (August 10, 2012): 2425–36. http://dx.doi.org/10.1007/s00707-012-0717-x.

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5

Cao, Chenxu, Zhiwu Zhu, Tiantian Fu, and Zhijie Liu. "A constitutive model for frozen soil based on rate-dependent damage evolution." International Journal of Damage Mechanics 27, no. 10 (November 19, 2017): 1589–600. http://dx.doi.org/10.1177/1056789517741339.

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Анотація:
The deformation of frozen soil under impact loading is usually accompanied by the evolution of internal defects and microdamage. By taking the strain and strain rates into account, a rate-dependent damage evolution law is proposed in this study, under the assumption of equivalent strain. Subsequently, a damage-modified rate-dependent constitutive model is proposed to describe the dynamic mechanical properties of frozen soil. A split Hopkinson pressure bar is utilized to test the dynamic mechanical response of frozen soil at different temperatures and high strain rates. The experimental results show that frozen soil produces obvious strain rate and temperature effects, and that there is a linear relationship between the peak stress and temperature. The theoretical results of the proposed constitutive model agree well with the experimental results, verifying the applicability of the model.
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6

Hadany, Lilach, and Sarah P. Otto. "Condition‐Dependent Sex and the Rate of Adaptation." American Naturalist 174, S1 (July 2009): S71—S78. http://dx.doi.org/10.1086/599086.

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7

Wan, Peng, Xiaoyan Lei, Bin Xu, and Hui Song. "A Strain Rate-Dependent Damage Evolution Model for Concrete Based on Experimental Results." Advances in Civil Engineering 2021 (May 19, 2021): 1–8. http://dx.doi.org/10.1155/2021/6643263.

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Анотація:
There are various definitions of damage variables from the existing damage models. The calculated damage value by the current methods still could not well correspond to the actual damage value. Therefore, it is necessary to establish a damage evolution model corresponding to the actual damage evolution. In this paper, a strain rate-sensitive isotropic damage model for plain concrete is proposed to describe its nonlinear behavior. Cyclic uniaxial compression tests were conducted on concrete samples at three strain rates of 10−3s−1, 10−4s−1, and 10−5s−1, respectively, and ultrasonic wave measurements were made at specified strain values during the loading progress. A damage variable was defined using the secant and initial moduli, and concrete damage evolution was then studied using the experimental results of the cyclic uniaxial compression tests conducted at the different strain rates. A viscoelastic stress-strain relationship, which considered the proposed damage evolution model, was presented according to the principles of irreversible thermodynamics. The model results agreed well with the experiment and indicated that the proposed damage evolution model can accurately characterize the development of macroscopic mechanical weakening of concrete. A damage-coupled viscoelastic constitutive relationship of concrete was recommended. It was concluded that the model could not only characterize the stress-strain response of materials under one-dimensional compressive load but also truly reflect the degradation law of the macromechanical properties of materials. The proposed damage model will advance the understanding of the failure process of concrete materials.
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8

Zou, Lianfeng, Wengao Zhao, Zhenyu Liu, Haiping Jia, Jianming Zheng, Guofeng Wang, Yong Yang, Ji-Guang Zhang, and Chongmin Wang. "Revealing Cycling Rate-Dependent Structure Evolution in Ni-Rich Layered Cathode Materials." ACS Energy Letters 3, no. 10 (September 14, 2018): 2433–40. http://dx.doi.org/10.1021/acsenergylett.8b01490.

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9

Liu, X. C., Y. F. Sun, T. Nagira, K. Ushioda, and H. Fujii. "Strain rate dependent micro-texture evolution in friction stir welding of copper." Materialia 6 (June 2019): 100302. http://dx.doi.org/10.1016/j.mtla.2019.100302.

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10

Lubarda, V. "On the evolution equation for the rest stress in rate-dependent plasticity." International Journal of Plasticity 18, no. 7 (July 2002): 895–918. http://dx.doi.org/10.1016/s0749-6419(01)00014-6.

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11

Rogowitz, Anna, Bernhard Grasemann, Benjamin Huet, and Gerlinde Habler. "Strain rate dependent calcite microfabric evolution – An experiment carried out by nature." Journal of Structural Geology 69 (December 2014): 1–17. http://dx.doi.org/10.1016/j.jsg.2014.08.004.

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12

Santos, Mauro, Daniel J. Borash, Amitabh Joshi, Nira Bounlutay, and Laurence D. Mueller. "DENSITY-DEPENDENT NATURAL SELECTION INDROSOPHILA: EVOLUTION OF GROWTH RATE AND BODY SIZE." Evolution 51, no. 2 (April 1997): 420–32. http://dx.doi.org/10.1111/j.1558-5646.1997.tb02429.x.

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13

Bass, Jon M., and J. T. Oden. "Numerical solution of the evolution equations of damage and rate-dependent plasticity." International Journal of Engineering Science 26, no. 7 (January 1988): 713–40. http://dx.doi.org/10.1016/0020-7225(88)90090-0.

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14

Ganjiani, Mehdi. "A thermodynamic consistent rate-dependent elastoplastic-damage model." International Journal of Damage Mechanics 27, no. 3 (November 12, 2016): 333–56. http://dx.doi.org/10.1177/1056789516676882.

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Анотація:
In this article, a rate-dependent elastoplastic-damage constitutive model considering the effect of strain rate has been developed. The derivation of this model has been established based on the irreversible thermodynamics with internal variables within the fundamentals of Continuum damage mechanics (CDM). For investigating the rate effect, an additional power function dependent on the effective strain rate has been involved in the plastic dissipation function (dynamic plastic yield surface). The damage has been assumed as a tensor-type variable and based on the energy equivalence hypothesis, the damage evolution has been developed. The proposed constitutive model has been implemented into user-defined subroutines UMAT and VUMAT in the finite-element program ABAQUS/(Standard and Explicit). For this purpose, the implicit and explicit stress integration algorithms of the model have been explained. The model has been validated by comparing the predicted results with experimental data conducted on Al2024-T3. These experiments are including the tensile and double-notched tests. Furthermore, the numerical results have been compared with some data available in the literature. The numerical examples show the excellent correlation between experiments and simulations for stress (or force) and damage results.
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15

Madenjian, Charles P. "Nighttime Pond Respiration Rate: Oxygen or Temperature Dependent?" Canadian Journal of Fisheries and Aquatic Sciences 47, no. 1 (January 1, 1990): 180–83. http://dx.doi.org/10.1139/f90-020.

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Two different models for the nighttime dissolved oxygen concentration (DO) dynamics in ponds were compared to determine which was more accurate. DO and water temperature were monitored overnight in marine shrimp (Penaeus vannamei and P. monodon) ponds; wind speed was also measured. The Whole Pond Respiration–Diffusion (WPRD) model, in which night respiration rate of the pond system is a function of water temperature, was fitted to observations of DO at dusk and approximately 3 h after dusk to generate predictions of pond DO at dawn The Oláh model, which is based on respiration rate varying in direct proportion to DO, was also applied to the same set of DO observations to generate predictions of dawn DO. The mean absolute values of the residuals (the residual is equal to observed dawn DO minus predicted dawn DO) from applications of the WPRD and Oláh models were 0.39 and 0.77 mg O2∙L−1, respectively, and the Oláh model showed consistent bias. The respiration rate of the pond system at night was therefore better described as a function of water temperature than as dependent on pond DO.
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16

Gallagher, M. C., M. Arnold, E. Kadaub, S. Culloty, R. M. O’Riordan, R. McAllen, and D. Rachinskii. "Competing barnacle species with a time dependent reproduction rate." Theoretical Population Biology 131 (February 2020): 12–24. http://dx.doi.org/10.1016/j.tpb.2019.11.001.

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17

Santos, Mauro, Daniel J. Borash, Amitabh Joshi, Nira Bounlutay, and Laurence D. Mueller. "Density-Dependent Natural Selection in Drosophila: Evolution of Growth Rate and Body Size." Evolution 51, no. 2 (April 1997): 420. http://dx.doi.org/10.2307/2411114.

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18

Joshi, Amitabh, and Laurence D. Mueller. "Evolution of Higher Feeding Rate in Drosophila Due to Density-Dependent Natural Selection." Evolution 42, no. 5 (September 1988): 1090. http://dx.doi.org/10.2307/2408924.

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19

Gu, Lin-lin, Zhen Wang, Feng Zhang, Fei Gao, and Xiao Wang. "Dynamic evolution of shear rate-dependent behavior of rock discontinuity under shearing condition." Journal of Central South University 28, no. 6 (June 2021): 1875–87. http://dx.doi.org/10.1007/s11771-021-4736-4.

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20

Wang, Li-Li, Feng-Hua Zhou, Zi-Jian Sun, Yong-Zhong Wang, and Shao-Qiu Shi. "Studies on Rate-dependent Macro-damage Evolution of Materials at High Strain Rates." International Journal of Damage Mechanics 19, no. 7 (February 8, 2010): 805–20. http://dx.doi.org/10.1177/1056789509359654.

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21

Hin, Vincent, and André M. Roos. "Evolution of size‐dependent intraspecific competition predicts body size scaling of metabolic rate." Functional Ecology 33, no. 3 (December 20, 2018): 479–90. http://dx.doi.org/10.1111/1365-2435.13253.

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22

Joshi, Amitabh, and Laurence D. Mueller. "EVOLUTION OF HIGHER FEEDING RATE IN DROSOPHILA DUE TO DENSITY-DEPENDENT NATURAL SELECTION." Evolution 42, no. 5 (September 1988): 1090–93. http://dx.doi.org/10.1111/j.1558-5646.1988.tb02527.x.

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23

Wang, L. L., and Z. J. Sun. "Studies on rate dependent damage evolution in polymer blends in high strain rates." Plastics, Rubber and Composites 37, no. 5-6 (June 2008): 246–50. http://dx.doi.org/10.1179/174328908x309303.

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24

Moore, Michael P. "Larval habitats impose trait-dependent limits on the direction and rate of adult evolution in dragonflies." Biology Letters 17, no. 5 (May 2021): 20210023. http://dx.doi.org/10.1098/rsbl.2021.0023.

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Natural selection on juveniles is often invoked as a constraint on adult evolution, but it remains unclear when such restrictions will have their greatest impact. Selection on juveniles could, for example, mainly limit the evolution of adult traits that mostly develop prior to maturity. Alternatively, selection on juveniles might primarily constrain the evolution of adult traits that experience weak or context-dependent selection in the adult stage. Using a comparative study of dragonflies, I tested these hypotheses by examining how a species’ larval habitat was related to the evolution of two adult traits that differ in development and exposure to selection: adult size and male ornamentation. Whereas adult size is fixed at metamorphosis and experiences consistent positive selection in the adult stage, ornaments develop throughout adulthood and provide context-dependent fitness benefits. My results show that species that develop in less stable larval habitats have smaller adult sizes and slower rates of adult size evolution. However, these risky larval habitats do not limit ornament expression or rates of ornament evolution. Selection on juveniles may therefore primarily affect the evolution of adult traits that mostly develop prior to maturity.
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25

Ozaki, Shingo, Takeru Matsuura, and Satoru Maegawa. "Rate-, state-, and pressure-dependent friction model based on the elastoplastic theory." Friction 8, no. 4 (January 4, 2020): 768–83. http://dx.doi.org/10.1007/s40544-019-0321-3.

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AbstractAdhesion is one of essences with respect to rubber friction because the magnitude of the friction force is closely related to the magnitude of adhesion on a real contact area. However, the real contact area during sliding depends on the state and history of the contact surface. Therefore, the friction force occasionally exhibits rate-, state-, and pressure dependency. In this study, to rationally describe friction and simulate boundary value problems, a rate-, state-, and pressure-dependent friction model based on the elastoplastic theory was formulated. First, the evolution law for the friction coefficient was prescribed. Next, a nonlinear sliding surface (frictional criterion) was adopted, and several other evolution laws for internal state variables were prescribed. Subsequently, the typical response characteristics of the proposed friction model were demonstrated, and its validity was verified by comparing the obtained results with those of experiments conducted considering the contact surface between a rough rubber hemisphere and smooth acrylic plate.
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26

Wang, Chao, Clinton G. Wiener, Masafumi Fukuto, Ruipeng Li, Kevin G. Yager, R. A. Weiss, and Bryan D. Vogt. "Strain rate dependent nanostructure of hydrogels with reversible hydrophobic associations during uniaxial extension." Soft Matter 15, no. 2 (2019): 227–36. http://dx.doi.org/10.1039/c8sm02165a.

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27

Lewis, B. M., and Yervant Terzian. "The IR Color Evolution of Circumstellar Shells." Highlights of Astronomy 9 (1992): 609–12. http://dx.doi.org/10.1017/s1539299600009825.

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AbstractThe far IR colors of circumstellar shells are delimited by those with masers; few other objects share the same colors. The resulting (25–12)µm color range is primarily due to secular increases in the mass-loss rate, up to a progenitor-mass dependent maximum. Only the most massive progenitors can sustain the mass-loss rate required by the reddest shells.
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28

Mayrose, Itay, and Sarah P. Otto. "A Likelihood Method for Detecting Trait-Dependent Shifts in the Rate of Molecular Evolution." Molecular Biology and Evolution 28, no. 1 (October 20, 2010): 759–70. http://dx.doi.org/10.1093/molbev/msq263.

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29

Viesca, Robert C. "Self-similar slip instability on interfaces with rate- and state-dependent friction." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 472, no. 2192 (August 2016): 20160254. http://dx.doi.org/10.1098/rspa.2016.0254.

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Анотація:
We examine the development of a frictional instability, with diverging sliding rate, at the interface of elastic bodies in contact. Evolution of friction is determined by a slip rate and state dependence. Following Viesca (2016 Phys. Rev. E 93 , 060202(R). ( doi:10.1103/PhysRevE.93.060202 )), we show through an appropriate change of variable, the existence of blow-up solutions that are fixed points of a dynamical system. The solutions show self-similarity of the simple variety: separable dependence of time and space. For an interface with uniform frictional properties, there is a single-problem parameter. We examine the linear stability of these fixed points, as this problem parameter is varied. Specifically, we consider two archetypical elastic settings of the slip surface, in which interactions between points on the surface are either local or non-local. We show that, independent of the nature of elastic interactions, the fixed-points lose stability in the same matter as the parameter is increased towards a limit value: an apparently infinite sequence of Hopf bifurcations. However, for any value of the parameter, the nonlinear development of the instability is attraction, if not asymptotic convergence, towards these fixed points, owing to the existence of stable eigenmodes. For comparison, we perform numerical solutions of the original evolution equations and find precise agreement with the results of the analysis.
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30

Li, J. Q., Tao Tao Dong, and Min Jie Wang. "Research on Dynamic Constitutive Relation of Materials Taking Account of Damage Evolution and Fracture Law for High Speed Cutting." Advanced Materials Research 188 (March 2011): 224–29. http://dx.doi.org/10.4028/www.scientific.net/amr.188.224.

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The adiabatic shear, which may produce serrated chip, usually occurs for a large number of materials in high speed machining. Adiabatic shear band is an important damage model for metals under high-velocity deformation process. The damage evolution of micro-voids in adiabatic shear bands resulted in material fracture finally. Now the thermal softening effect, the strain rate harding effect and the strain harding effect have been discussed extensively in literature, but there is very little research on its damage effect. Based on the experiments of predecessors, this paper presents a new damage evolution equation that is dependent on strain, strain rate and is suitable for the description of voids damage evolution in adiabatic shear band. The corresponding rate-dependent constitutive relation taking account of damage evolution and temperature are proposed. The predicted results are in good agreement with the experiment datum.
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31

May, Michael R., and Brian R. Moore. "A Bayesian Approach for Inferring the Impact of a Discrete Character on Rates of Continuous-Character Evolution in the Presence of Background-Rate Variation." Systematic Biology 69, no. 3 (October 29, 2019): 530–44. http://dx.doi.org/10.1093/sysbio/syz069.

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Abstract Understanding how and why rates of character evolution vary across the Tree of Life is central to many evolutionary questions; for example, does the trophic apparatus (a set of continuous characters) evolve at a higher rate in fish lineages that dwell in reef versus nonreef habitats (a discrete character)? Existing approaches for inferring the relationship between a discrete character and rates of continuous-character evolution rely on comparing a null model (in which rates of continuous-character evolution are constant across lineages) to an alternative model (in which rates of continuous-character evolution depend on the state of the discrete character under consideration). However, these approaches are susceptible to a “straw-man” effect: the influence of the discrete character is inflated because the null model is extremely unrealistic. Here, we describe MuSSCRat, a Bayesian approach for inferring the impact of a discrete trait on rates of continuous-character evolution in the presence of alternative sources of rate variation (“background-rate variation”). We demonstrate by simulation that our method is able to reliably infer the degree of state-dependent rate variation, and show that ignoring background-rate variation leads to biased inferences regarding the degree of state-dependent rate variation in grunts (the fish group Haemulidae). [Bayesian phylogenetic comparative methods; continuous-character evolution; data augmentation; discrete-character evolution.]
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32

Minter, Ewan J. A., Andy Fenton, Jennifer Cooper, and David J. S. Montagnes. "Prey-Dependent Mortality Rate: A Critical Parameter in Microbial Models." Microbial Ecology 62, no. 1 (March 11, 2011): 155–61. http://dx.doi.org/10.1007/s00248-011-9836-5.

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33

Xu, C. Kevin, Yinghe Zhao, N. Scoville, P. Capak, N. Drory, and Y. Gao. "MAJOR-MERGER GALAXY PAIRS IN THE COSMOS FIELD—MASS-DEPENDENT MERGER RATE EVOLUTION SINCEz= 1." Astrophysical Journal 747, no. 2 (February 16, 2012): 85. http://dx.doi.org/10.1088/0004-637x/747/2/85.

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34

Sharma, Neeraj, Nuria Tapia-Ruiz, Gurpreet Singh, A. Robert Armstrong, James C. Pramudita, Helen E. A. Brand, Juliette Billaud, Peter G. Bruce, and Teofilo Rojo. "Rate Dependent Performance Related to Crystal Structure Evolution of Na0.67Mn0.8Mg0.2O2 in a Sodium-Ion Battery." Chemistry of Materials 27, no. 20 (October 15, 2015): 6976–86. http://dx.doi.org/10.1021/acs.chemmater.5b02142.

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35

Zhang, Fangteng, Mindaugas Gecevičius, Qiuqun Chen, Hang Zhang, Ye Dai, and Jianrong Qiu. "Evolution of polarization dependent microstructures induced by high repetition rate femtosecond laser irradiation in glass." Optics Express 24, no. 19 (September 6, 2016): 21353. http://dx.doi.org/10.1364/oe.24.021353.

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36

Zavodnik, Jan, Andrej Košmrlj, and Miha Brojan. "Rate-dependent evolution of wrinkling films due to growth on semi-infinite planar viscoelastic substrates." Journal of the Mechanics and Physics of Solids 173 (April 2023): 105219. http://dx.doi.org/10.1016/j.jmps.2023.105219.

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37

Blagov, Boris, and Michael Funke. "THE REGIME-DEPENDENT EVOLUTION OF CREDIBILITY: A FRESH LOOK AT HONG KONG'S LINKED EXCHANGE RATE SYSTEM." Macroeconomic Dynamics 23, no. 06 (April 22, 2018): 2434–68. http://dx.doi.org/10.1017/s136510051700075x.

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An estimated Markov-switching DSGE modeling framework that allows for parameter shifts across regimes is employed to test the hypothesis of regime-dependent credibility of Hong Kong's linked exchange rate system. The baseline model distinguishes two regimes with respect to the time-series properties of the risk premium. Regime-dependent impulse responses to macroeconomic shocks reveal substantial differences in spreads. To test the sensitivity of the results, a number of robustness checks are performed. The findings contribute to efforts at modeling exchange rate regime credibility as a nonlinear process with two distinct regimes.
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38

Phillips, J. P. "Stellar Evolution and the Planetary Nebula Formation Rate." Symposium - International Astronomical Union 131 (1989): 425–42. http://dx.doi.org/10.1017/s0074180900138823.

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A knowledge of the formation rate of planetary nebulae is crucial to our understanding of a wide range of physical environments and processes, and as such has been fitfully investigated over the last forty or so years. The elemental composition of the interstellar medium, for instance, and in particular the seeding of the IS medium by CNO and s-process materials, turns out to be rather sensitively dependent upon the local rate of PN formation χ(PN) (Salpeter, 1978, Pottasch, 1984; Tinsley, 1978; and Wood et al, 1983). Similarly, and to varying degrees, the ionisation balance of the I.S. medium (cf. Pottasch, 1984; Salpeter, 1978), composition and number density of I.S. grains (Natta and Panagia, 1981), and ultimately the galactic star formation rate (cf. Miller and Scalo, 1979) can all (more or less directly) trace a dependency upon χ(PN). Finally, χ(PN) has proven historically important in establishing the evolutionary status of PN (cf. Abell and Goldreich, 1966), and is expected to be directly related to the rate of formation of white dwarfs, the death-rate of AGB-type stars (Mira variables, OH/IR sources), and the main-sequence turn-off rate in the mass range 2 ≲ M/M⊙ ≲ 10, some 1010 years ago.
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39

Shih, Shao Chiu, Yong Zhong Wang, and Li Li Wang. "The Improved Johnson-Cook’s Strength Model Taking Account of the Rate-Dependent Micro-Damage Evolution for C30 Concrete." Key Engineering Materials 326-328 (December 2006): 1101–4. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.1101.

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Анотація:
The dynamic mechanical behavior of C30 concrete under a wide range of strain rates from 10-4s-1 up to 102s-1 is studied. According to Johnson-Cook’s strength model, the strain rate coefficients and related material constants of C30 concrete subjected to large strains, high strain rates and high pressures are determined experimentally: C=0.34*10-1, A=1.05, B=1.65, N=0.76, TC =3.162MPa, fc’=39.2MPa. The damage evolution for C30 concrete is a rate-dependent process, which can be formulated to a rate-dependent damage evolution law in a simple form for engineering application. When ε > ε th, ( ) 1 D th D = K ε&α − ε −ε . The corresponding dynamic coefficients of C30 concrete are also obtained from impact experimental results: KD=530.2, a=0.83. Due to a<1, the damage evolution corresponds to an impact toughening process that coincide well with the dynamic experimental results for C30 concrete.
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40

Mareau, C., and M. R. Daymond. "Study of internal strain evolution in Zircaloy-2 using polycrystalline models: Comparison between a rate-dependent and a rate-independent formulation." Acta Materialia 58, no. 9 (May 2010): 3313–25. http://dx.doi.org/10.1016/j.actamat.2010.02.005.

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41

Morland, Leslie W., and Ryszard Staroszczyk. "Steady radial ice-sheet flow with fabric evolution." Journal of Glaciology 52, no. 177 (2006): 267–80. http://dx.doi.org/10.3189/172756506781828719.

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AbstractReorientation of individual crystal glide planes, as isotropic surface ice is deformed during its passage to depth in an ice sheet, creates a fabric and associated anisotropy. We adopt an evolving orthotropic viscous law which was developed to reflect the induced anisotropy arising from the mean rotation of crystal axes during deformation. This expresses the deviatoric stress in terms of the strain rate, strain and three structure tensors based on the principal stretch axes, and involves one fabric response function which determines the strength of the anisotropy. The initial isotropic response enters as a multiplying factor depending on a strain-rate invariant and incorporating a temperature-dependent rate factor. The fabric response function has been constructed by correlations with complete (idealized) uniaxial compression and shearing responses for both ‘cold’ and ‘warm’ ice. The possible effects of such fabric evolution are now illustrated by determining steady radially symmetric flow solutions for an ice sheet with a prescribed temperature distribution and subject to an elevation-dependent surface accumulation/ablation distribution, zero basal melting and a prescribed basal sliding law. Comparisons are made with solutions for the conventional isotropic viscous law, for a flat bed, for a bed with a single modest slope hump and for a bed with a single modest slope hollow, for both cold and warm ice.
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42

Yang, Qianxi, and Guoqiang Li. "Temperature and rate dependent thermomechanical modeling of shape memory polymers with physics based phase evolution law." International Journal of Plasticity 80 (May 2016): 168–86. http://dx.doi.org/10.1016/j.ijplas.2015.09.005.

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43

Kumar, S. S. Satheesh, T. Raghu, Pinaki P. Bhattacharjee, G. Appa Rao, and Utpal Borah. "Strain rate dependent microstructural evolution during hot deformation of a hot isostatically processed nickel base superalloy." Journal of Alloys and Compounds 681 (October 2016): 28–42. http://dx.doi.org/10.1016/j.jallcom.2016.04.185.

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44

Duchêne, Sebastián, Edward C. Holmes, and Simon Y. W. Ho. "Analyses of evolutionary dynamics in viruses are hindered by a time-dependent bias in rate estimates." Proceedings of the Royal Society B: Biological Sciences 281, no. 1786 (July 7, 2014): 20140732. http://dx.doi.org/10.1098/rspb.2014.0732.

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Time-scales of viral evolution and emergence have been studied widely, but are often poorly understood. Molecular analyses of viral evolutionary time-scales generally rely on estimates of rates of nucleotide substitution, which vary by several orders of magnitude depending on the timeframe of measurement. We analysed data from all major groups of viruses and found a strong negative relationship between estimates of nucleotide substitution rate and evolutionary timescale. Strikingly, this relationship was upheld both within and among diverse groups of viruses. A detailed case study of primate lentiviruses revealed that the combined effects of sequence saturation and purifying selection can explain this time-dependent pattern of rate variation. Therefore, our analyses show that studies of evolutionary time-scales in viruses require a reconsideration of substitution rates as a dynamic, rather than as a static, feature of molecular evolution. Improved modelling of viral evolutionary rates has the potential to change our understanding of virus origins.
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45

Schulkes, R. M. S. M. "The evolution and bifurcation of a pendant drop." Journal of Fluid Mechanics 278 (November 10, 1994): 83–100. http://dx.doi.org/10.1017/s0022112094003629.

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In this paper we calculate how a pendant drop evolves at the end of a nozzle when the volume of the drop increases steadily with time. We find that the character of the evolution is strongly dependent on the growth rate of the drop and the radius of the nozzle. Typically we find that once the drop has become unstable, two bifurcations occur shortly after each other when the growth rate of the drop is slow. For large growth rates the bifurcations are well-separated in time. We are able to calculate the volumes of the drops after the bifurcations. A comparison with experimental data shows a satisfactory agreement.
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46

Osnas, Erik E., and Andrew P. Dobson. "Evolution of virulence when transmission occurs before disease." Biology Letters 6, no. 4 (February 10, 2010): 505–8. http://dx.doi.org/10.1098/rsbl.2009.1019.

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Most models of virulence evolution assume that transmission and virulence are constant during an infection. In many viral (HIV and influenza), bacterial (TB) and prion (BSE and CWD) systems, disease-induced mortality occurs long after the host becomes infectious. Therefore, we constructed a model with two infected classes that differ in transmission rate and virulence in order to understand how the evolutionarily stable strategy (ESS) depends on the relative difference in transmission and virulence between classes, on the transition rate between classes and on the recovery rate from the second class. We find that ESS virulence decreases when expressed early in the infection or when transmission occurs late in an infection. When virulence occurred relatively equally in each class and there was disease recovery, ESS virulence increased with increased transition rate. In contrast, ESS virulence first increased and then decreased with transition rate when there was little virulence early in the infection and a rapid recovery rate. This model predicts that ESS virulence is highly dependent on the timing of transmission and pathology after infection; thus, pathogen evolution may either increase or decrease virulence after emergence in a new host.
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47

Jiang, Hao, Zongyue Fan, Jian Lu, and Bo Li. "Micromechanical Studies of Strain Rate Dependent Compressive Strength in Brittle Polycrystalline Materials." International Journal of Computational Methods 16, no. 04 (May 13, 2019): 1844011. http://dx.doi.org/10.1142/s0219876218440115.

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We propose a novel computational model for the high fidelity prediction of failure mechanisms in brittle polycrystalline materials. A three-dimensional finite element model of the polycrystalline structure is reconstructed to explicitly account for the micro-features such as grain sizes, grain orientations, and grain boundary misorientations. Grain boundaries are explicitly represented by a thin layer of elements with non-zero misorientation angles. In addition, the Eigen-fracture algorithm is employed to predict the crack nucleation and propagation in the grain structure. In the framework of variational fracture mechanics, an equivalent energy release rate is defined at each finite element to evaluate the local failure state by comparing to the critical energy release rate, which varies at the grain boundaries and the interior of grains. Moreover, constitutive models are considered as functions of the local microstructure features. As a result, a direct mesoscale simulation model is developed to resolve the anisotropic response, intergranular and transgranular fractures during the microstructure evolution of brittle materials under general loading conditions. A micromechanics-based interpretation for the rate dependent strength of brittle materials is derived and verified in examples of dynamic compression tests. In specific, the compressive dynamic response of hexagonal SiC with equiaxed grain structures is studied under different strain rates.
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48

Di Fazio, A. "A New Theory of Star Formation: Analytical Mass Function and Star Formation Rate." Symposium - International Astronomical Union 115 (1987): 442–43. http://dx.doi.org/10.1017/s0074180900096182.

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An analytical, theoretical, time-dependent initial mass function is derived for the objects created in the fragmentation of a gravitationally unstable gas protocloud. The mass spectrum depends on the chemical-dynamical-radiative evolution of the protocloud and it peaks at a mass slightly greater than the minimum Jeans mass attained throughout the evolution. A fragmentation rate mass spectrum is also analytically derived.
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49

Rybnikov, Sviatoslav R., Zeev M. Frenkel, and Abraham B. Korol. "What drives the evolution of condition-dependent recombination in diploids? Some insights from simulation modelling." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1736 (November 6, 2017): 20160460. http://dx.doi.org/10.1098/rstb.2016.0460.

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While the evolutionary advantages of non-zero recombination rates have prompted diverse theoretical explanations, the evolution of essential recombination features remains underexplored. We focused on one such feature, the condition dependence of recombination, viewed as the variation in within-generation sensitivity of recombination to external (environment) and/or internal (genotype) conditions. Limited empirical evidence for its existence comes mainly from diploids, whereas theoretical models show that it only easily evolves in haploids. The evolution of condition-dependent recombination can be explained by its advantage for the selected system (indirect effect), or by benefits to modifier alleles, ensuring this strategy regardless of effects on the selected system (direct effect). We considered infinite panmictic populations of diploids exposed to a cyclical two-state environment. Each organism had three selected loci. Examining allele dynamics at a fourth, selectively neutral recombination modifier locus, we frequently observed that a modifier allele conferring condition-dependent recombination between the selected loci displaced the allele conferring the optimal constant recombination rate. Our simulations also confirm the results of theoretical studies showing that condition-dependent recombination cannot evolve in diploids on the basis of direct fitness-dependent effects alone. Therefore, the evolution of condition-dependent recombination in diploids can be driven by indirect effects alone, i.e. by modifier effects on the selected system. This article is part of the themed issue ‘Evolutionary causes and consequences of recombination rate variation in sexual organisms’.
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50

Shao, Muyao, Yiru Wang, Zhiyuan Gao, and Xiaojin Zhu. "Discrete-time rate-dependent hysteresis modeling and parameter identification of piezoelectric actuators." Transactions of the Institute of Measurement and Control 44, no. 10 (January 12, 2022): 1968–78. http://dx.doi.org/10.1177/01423312211069364.

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A discrete-time-modified Bouc–Wen model is proposed to describe the non-symmetrical and rate-dependent hysteresis of piezoelectric actuators for micro-vibration control applications. The modified model combines a non-symmetrical Bouc–Wen model and a frequency-dependent dynamic module. A series of experiments are conducted to characterize the rate-dependent hysteresis of piezoelectric stack actuators under sinusoidal excitations at a range of 1 to 20 Hz. The experimental results verify the validity of the modified model. The modified Bouc–Wen model increases the complexity of Bouc–Wen hysteresis nonlinear differential equation, which brings difficulties to parameter identification. To identify the parameters of Bouc–Wen model, an improved hybrid differential evolution and Jaya (DE-Jaya) algorithm is introduced with a hybrid mutant operator and Jaya operator that tried to balance between convergence speed and solution accuracy. The improved algorithm is tested on benchmark functions and compared with other optimizations to prove its effectiveness. The comparison results show that hybrid DE-Jaya algorithm has better performance in convergence speed and solution accuracy. The identified discrete-time-modified Bouc–Wen model is used as the secondary path in a filtered-x variable step-size affine projection algorithm (FXVSSAPA), and experimental verifications are done on a micro-vibration control platform. The experimental results show that the FXVSSAPA algorithm can converge to the steady-state error faster and verify the effectiveness of the proposed discrete-time-modified Bouc–Wen model.
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