Academic literature on the topic 'Rate-dependent evolution'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Rate-dependent evolution.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Rate-dependent evolution"

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.

Full text
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
Abstract:
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.
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
Abstract:
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.
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
APA, Harvard, Vancouver, ISO, and other styles
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.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Rate-dependent evolution"

1

Aiewsakun, Pakorn. "Paleovirology : connecting recent and ancient viral evolution." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:370e0a28-ee67-441f-bce6-42ad4cdf9365.

Full text
Abstract:
Endogenous viral elements, or viral genomic fossils, have proven extremely valuable in the study of the macroevolution of viruses, providing important, and otherwise unobtainable, insights into the ancient origin of viruses, and how their ancestors might have co-evolved with their hosts in the distant past. This type of investigation falls within the realm of paleovirology—the study of ancient viruses. Investigations of extant viruses and paleovirological analyses, however, often give conflicting results, especially those concerning viral evolutionary rates and timescales. Reconciling these two types of analyses is a necessary step towards a better understanding of the overall long-term evolutionary dynamics of viruses. The main study system of this thesis is foamy viruses (FVs). FVs are characterised by their stable co-speciation history with their hosts, allowing their evolutionary dynamics to be modelled and investigated over various timescales. This unique evolutionary feature makes FVs one of the best subjects for connecting recent and ancient viral evolution. The work here reports the discovery of several endogenous mammalian FVs, and examines how mammalian FVs co-evolve with their hosts. Analyses reveal a co-diversifying history of the two that could be dated back to the basal radiation of eutherians more than 100 million years ago. However, a small number of ancient FV cross-species transmissions could still be found, mostly involving New World monkey FVs. Based on this extended FV-mammal co-speciation pattern, this thesis investigates the long-term evolutionary rate dynamics of FVs, and shows that the rate estimates of FV evolution appear to decrease continuously as the rate measurement timescale increases, following a power-law decay function. The work presented here also shows that this so-called 'time-dependent rate phenomenon' is in fact a pervasive evolutionary feature of all viruses, and surprisingly, the rate estimates of evolution of all viruses seem to decay at the same speed, decreasing by approximately half for every 3-fold increase in the measurement timescale. Based on this power-law rate-decay pattern, we could infer evolutionary timescales of modern-day lentiviruses that are consistent with paleovirological analyses for the first time. Finally, this thesis reports the discovery of basal FV-like endogenous retroviruses (FLERVs) in amphibian and fish genomes. Phylogenetic analyses reveal that the progenitors of ray-finned fish FLERVs co-diversify broadly with their fish hosts, but also suggest that there might have been several ancient viral cross-class transmissions, involving lobe-finned fish, shark, and frog FLERVs. Again, by using the power-law rate-decay model, analyses in this thesis suggest that this major retroviral clade has an ancient Ordovician marine origin, originating together with their jawed vertebrate hosts more than 450 million years ago. This finding implies that the origin of retroviruses as a whole must be in the early Paleozoic Era, if not earlier. The results presented here bridge ancient and recent viral evolution.
APA, Harvard, Vancouver, ISO, and other styles
2

Toräng, Per. "Pollinators, Enemies, Drought, and the Evolution of Reproductive Traits in Primula farinosa." Doctoral thesis, Uppsala universitet, Växtekologi och evolution, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8207.

Full text
Abstract:
In this thesis, I combined comparative and experimental approaches to examine selection on reproductive traits and population differentiation in the insect-pollinated, self-incompatible, perennial herb Primula farinosa. More specifically, I (1) determined whether the effects of floral display and interactions with pollinators and seed predators, and plant reproductive success were frequency-dependent and affected by surrounding vegetation context, (2) examined the consequences of intermittent drought years on population dynamics using numerical simulations based on demographic data collected over seven years, (3) analyzed among-population differentiation in flowering phenology and reproductive allocation, and its relationship to soil-depth at the site of origin. A field experiment suggested that conspicuous plants facilitate inconspicuous plants in terms of pollinator attraction, and that the facilitation effect is contingent on the height of the surrounding vegetation. Further experiments revealed that both mutualistic and antagonistic interactions can result in frequency-dependent selection on floral display. Among inconspicuous plants, both fruit initiation, and damage from seed predators increased with the proportion of the conspicuous morph. The relative strength of these effects, and therefore their net outcome on the relationship between morph ratio and seed production varied among years. I combined information on vital rates and their relation to environmental conditions in simulations to predict future population viability in changing environments. Simulated stochastic population growth rate decreased with increasing frequency of drought years. Reproductive allocation varied significantly among populations both in the field and in a common-garden experiment, but was correlated with soil depth at the site of origin only in the field. The results suggest that among-population variation in reproductive effort in the field mainly reflects plastic responses to environmental conditions, and that this plasticity may be adaptive. The common-garden experiment suggested that the study populations have diverged genetically in flowering time.
APA, Harvard, Vancouver, ISO, and other styles
3

Oh, Joonyoung. "Numerical study of micro-scale damage evolution in time dependent fracture mechanics." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1117645391.

Full text
Abstract:
Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xvi, 147 p.; also includes graphics Includes bibliographical references (p. 143-147). Available online via OhioLINK's ETD Center
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Rate-dependent evolution"

1

Schaefer, Joseph D., and Isaac M. Daniel. "Strain-Rate-Dependent Yield Criteria for Composite Laminates." In Fracture, Fatigue, Failure and Damage Evolution, Volume 8, 197–208. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-21611-9_25.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

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." In Experimental Mechanics in Nano and Biotechnology, 1101–4. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-415-4.1101.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Hall, Richard B. "Viscoelastoplastic Damage with Maximum Rate of Dissipation-Based Growth Criterion and Tri-Component Lie Rate Decomposition." In Challenges in Mechanics of Time Dependent Materials, Fracture, Fatigue, Failure and Damage Evolution, Volume 2, 127–30. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29986-6_20.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Miao, Chengyun, and Hareesh V. Tippur. "Effect of Loading Rate on Fracture Behavior of Carbon Fiber Reinforced Polymer Composites." In Challenges in Mechanics of Time Dependent Materials, Fracture, Fatigue, Failure and Damage Evolution, Volume 2, 21–28. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29986-6_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Chen, H., and C. R. Siviour. "Application of Linear Viscoelastic Continuum Damage Theory to the Low and High Strain Rate Response of Thermoplastic Polyurethane." In Challenges in Mechanics of Time Dependent Materials, Fracture, Fatigue, Failure and Damage Evolution, Volume 2, 145–49. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29986-6_23.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Anand, Lallit, and Sanjay Govindjee. "Three-dimensional plasticity with kinematic and isotropic hardening." In Continuum Mechanics of Solids, 421–28. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198864721.003.0022.

Full text
Abstract:
This chapter provides an introduction to combined isotropic-kinematic hardening plasticity models in the three-dimensional small strain setting. The additive decomposition of the strain is introduced along with the concepts of plastic strain, equivalent tensile plastic strain, and back stress for three-dimensional problems. Plastic flow is discussed and defined, and a complete model of plasticity is formulated with Kuhn-Tucker loading/unloading conditions. The kinematic hardening model is based upon the Armstrong-Fredrick evolution law. Both rate-independent and rate-dependent (viscoplastic) models are discussed.
APA, Harvard, Vancouver, ISO, and other styles
7

Zinn-Justin, Jean. "Critical dynamics and renormalization group (RG)." In Quantum Field Theory and Critical Phenomena, 875–98. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198834625.003.0036.

Full text
Abstract:
Time evolution, near a phase transition in the critical domain of critical systems not far from equilibrium, using a Langevin-type evolution is studied. Typical quantities of interest are relaxation rates towards equilibrium, time-dependent correlation functions and transport coefficients. The main motivation for such a study is that, in systems in which the dynamics is local (on short time-scales, a modification of a dynamic variable has an influence only locally in space) when the correlation length becomes large, a large time-scale emerges, which characterizes the rate of time evolution. This phenomenon called critical slowing down leads to universal behaviour and scaling laws for time-dependent quantities. In contrast with the situation in static critical phenomena, there is no clean and systematic derivation of the dynamical equations governing the time evolution in the critical domain, because often the time evolution is influenced by conservation laws involving the order parameter, or other variables like energy, momentum, angular momentum, currents and so on. Indeed, the equilibrium distribution does not determine the driving force in the Langevin equation, but only the dissipative couplings are generated by the derivative of the equilibrium Hamiltonian, and directly related to the static properties. The purely dissipative Langevin equation specifically discussed, corresponding to static models like the f4 field theory and two-dimensional models. Renormalization group (RG) equations are derived, and dynamical scaling relations established.
APA, Harvard, Vancouver, ISO, and other styles
8

Tuljapurkar, Shripad, and Wenyun Zuo. "Evolutionary Demography." In Demographic Methods across the Tree of Life, 273–84. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198838609.003.0016.

Full text
Abstract:
Evolutionary demography has grown rapidly in recent years, as the biological topics of life history evolution and evolution in population with complex life cycles have benefitted from and contributed to a broader focus on evolutionary biodemography. This chapter provides a critical summary of the central ideas and methods. The authors emphasise theoretical methods, starting with the main ideas that have attracted attention in the field, the assumptions behind these, and efforts to relax those assumptions, and provide a short account of some new directions. The chapter begins with the classic work of Peter Medawar and William Hamilton and discusses the connections, applications, assumptions, and limitations related to their ideas and results, e.g. sensitivity and corresponding elasticity of growth rate on fertility and survival. It highlights extensions to variable environments and the large body of theory around that topic. Next the chapter discusses how these theoretical methods are related to analyses and theories of post-reproductive life, via the general concept of ‘borrowing fitness’. Finally, the chapter discusses nonlinear models of mutation and selection and density-dependent models.
APA, Harvard, Vancouver, ISO, and other styles
9

Epstein, Irving R., and John A. Pojman. "Polymer Systems." In An Introduction to Nonlinear Chemical Dynamics. Oxford University Press, 1998. http://dx.doi.org/10.1093/oso/9780195096705.003.0017.

Full text
Abstract:
In the classic 1967 film “The Graduate” the protagonist, Benjamin (Dustin Hoffman), is attempting to plan his postcollege path. His neighbor provides one word of advice, “Plastics.” This counsel has become part of American culture and is often parodied. But, it is good advice, because not since the transformations from stone to bronze and then to iron have new materials so completely transformed a society. Plastics made from synthetic polymers are ubiquitous, from Tupperware to artificial hearts. About half the world’s chemists work in polymer-related industries. In this chapter, we will survey some of the work that has been done in applying nonlinear dynamics to polymerization processes. These systems differ from those we have considered so far because they do not involve redox reactions. We will consider polymerization reactions in a CSTR that exhibit oscillations through the coupling of temperature-dependent viscosity and viscosity-dependent rate constants. Emulsion polymerization, which produces small polymer particles dispersed in water, can also oscillate in a CSTR. Both types of systems are important industrially, and their stabilities have been studied by engineers with the goal of eliminating their time-dependent behavior. Our favorite oscillating system, the Belousov-Zhabotinsky reaction, can be used to create an isothermal periodic polymerization reaction in either a batch or continuous system. This, however, is not a practical system because of the cost of the reagents. In most industrial processes, nonlinear behavior is seen not as an advantage but as something to be avoided. However, we will look at several reaction-diffusion systems that have desirable properties precisely because of their nonlinear behavior. Replication of RNA is autocatalytic and can occur as a traveling front. Since not all RNA molecules replicate equally well, faster mutants gradually take over. At each mutation, the front propagates faster. Evolution can be directly observed in a test tube. Propagating polymerization fronts of synthetic polymers may be useful for making new materials, and they are interesting because of the rich array of nonlinear phenomena they show, with pulsations, convection, and spinning fronts. Finally, we will consider photopolymerization systems that exhibit spatial pattern formation on the micron scale, which can be used to control the macroscopic properties.
APA, Harvard, Vancouver, ISO, and other styles
10

Tatar, Marc. "Senescence." In Evolutionary Ecology. Oxford University Press, 2001. http://dx.doi.org/10.1093/oso/9780195131543.003.0015.

Full text
Abstract:
At all taxonomic levels, there exists tremendous variation in life expectancy. A field mouse Peromyscus may live 1.2 years, while the African elephant may persist for 60 years, and even a mousesized bat such as Corynorhinus rafinesquei lives a healthy 20 years (Promislow 1991). Part of this variance is caused by differences in ecological risks, rodents being perhaps the most susceptible to predation, and to vagaries of climate and resources. Another portion is caused by differences in senescence, the intrinsic degeneration of function that produces progressive decrement in age-specific survival and fecundity. Senescence occurs in natural populations, where it affects life expectancy and reproduction as can be seen, for instance, from the progressive change in age-specific mortality and maternity of lion and baboon in East Africa. The occurrence of senescence and of the widespread variation in longevity presents a paradox: How does the age-dependent deterioration of fitness components evolve under natural selection? The conceptual and empirical resolutions to this problem will be explored in this chapter. We shall see that the force of natural selection does not weigh equally on all ages and that there is therefore an increased chance for genes with late-age-deleterious effects to be expressed. Life histories are expected to be optimized to regulate intrinsic deterioration, and in this way, longevity evolves despite the maladaptive nature of senescence. From this framework, we will then consider how the model is tested, both through studies of laboratory evolution and of natural variation, and through the physiological and molecular dissection of constraints underlying trade-offs between reproduction and longevity. As humans are well aware from personal experience, performance and physical condition progressively deteriorate with adult age. And in us, as well as in many other species, mortality rates progressively increase with cohort age. Medawar (1955), followed by Williams (1957), stated the underlying assumption connecting these events: Senescent decline in function causes a progressive increase in mortality rate. Although mortality may increase episodically across some age classes, such as with increases in reproductive effort, we assume that the continuous increase of mortality across the range of adult ages represents our best estimate of senescence.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Rate-dependent evolution"

1

Bogdanor, Michael, Robert D. Crouch, Stephen B. Clay, and Caglar Oskay. "Modeling Rate Dependent Damage Evolution in Composite Structures." In 54th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2013. http://dx.doi.org/10.2514/6.2013-1763.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Regueiro, Richard A., Douglas J. Bammann, Esteban B. Marin, and George C. Johnson. "Finite Deformation Elastoplasticity for Rate and Temperature Dependent Polycrystalline Metals." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-63179.

Full text
Abstract:
An elastoplasticity model is formulated and demonstrated in one-dimension (1D) for modeling finite deformations in poly-crystalline metals. Quasi-static to high strain rate effects as well as temperature sensitivity are included. A multiplicative decomposition of the deformation gradient into elastic, plastic, and thermal parts, that includes a volumetric/isochoric split of the elastic stretching tensor is assumed. The kinematics and thermodynamic formulation lead to constitutive equations, stresses, and constraints on the evolution of the internal state variables. The model accounts for (i) dislocation drag effects on flow stress, and (ii) generation (hardening) and annihilation (recovery) of statistically-stored dislocations (SSDs). The resulting model is normalized to dimensionless form to allow dimensionless material parameters fit for one metal to approximate the behavior of another metal of similar lattice structure, if data are limited. One dimensional material parameter fitting is demonstrated for two refractory metals, body centered cubic (bcc) Tantalum and Tungsten.
APA, Harvard, Vancouver, ISO, and other styles
3

Hartl, Darren, George Chatzigeorgiou, and Dimitris Lagoudas. "Three-Dimensional Modeling of Rate-Dependent Deformation in Shape Memory Alloys at High Temperatures." In ASME 2009 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2009. http://dx.doi.org/10.1115/smasis2009-1468.

Full text
Abstract:
Active structures composed of Shape Memory Alloys (SMAs) and High Temperature SMAs (HTSMAs) continue to be developed for applications that benefit from solid-state actuation. The need to account for the response of these materials under non-conventional loading paths that include elevated temperature conditions has become important. Conventional SMAs are exposed to such temperatures during processing, including final shape-setting. HTSMAs, by virtue of their title, are exposed to such high temperatures during transformation. This work addresses new developments in the constitutive modeling and numerical analysis pertaining to irrecoverable inelasticity in SMAs at high temperatures, where this behavior becomes rate-dependent. The description of such behavior requires the development of a theoretical framework able to capture the coupling between the rate-independent transformation and the rate-dependent creep. The proposed phase transformation-viscoplastic model is based on continuum thermodynamics; here the elastic relations, the inelastic evolution equations, and the transformation criteria are summarized. The evolution equation for the viscoplastic strain is non-homogeneous in time, and thus rate-dependency results. The viscoplastic parameters are generally assumed to exhibit a strong dependence on temperature. The rate-independent and rate-dependent constitutive equations that comprise the full 3-D model are numerically integrated using a scheme that accounts for both transformation and viscoplastic deformation in a coupled manner. The implementation allows for 3-D analysis of SMA bodies using an FEA framework that includes Abaqus and an associated user material subroutine. Example analyses are discussed, including shape-setting in a conventional SMA and experimentally validated structural analysis of an HTSMA specimen.
APA, Harvard, Vancouver, ISO, and other styles
4

Wang, L. L., S. Q. Shi, J. Y. Chen, D. J. Huang, and L. J. Shen. "RATE-DEPENDENT IMPACT BEHAVIOR OF CEMENT MORTAR UNDER THREE DIFFERENT STRESS-STATES BY TAKING ACCOUNT OF DAMAGE EVOLUTION." In Proceedings of the Second International Conference. WORLD SCIENTIFIC, 2002. http://dx.doi.org/10.1142/9789812776228_0143.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Fan, C. H., J. Sun, and J. P. Longtin. "Localized Electron Evolution Induced by Femtosecond Laser Pulses in Water." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/htd-24349.

Full text
Abstract:
Abstract Optical breakdown by ultrashort laser pulses in dielectrics presents an efficient method to deposit laser energy into materials that otherwise exhibit minimal absorption at low laser intensities. During optical breakdown, a high density of free electrons is formed in the material, which dominates energy absorption, and, in turn, the material removal rate during ultrafast laser-material processing. Classical models assume spatially uniform electron population and constant laser intensity in the focal region, which results in a time-dependent expressions only, i.e., the rate equations, to predict electron evolution induced by nanosecond and picosecond pulses. For femtosecond pulses, however, the small spatial extent of the pulse requires that the pulse propagation be considered, which results in inhomogeneous plasma and localized electron formation during optical breakdown. In this work, a femtosecond breakdown model is combined with the classical rate equations to determine both time- and position-dependent electron density during femtosecond optical breakdown in water. The model exhibits good agreement when compared with experimental results. For other transparent or moderately absorbing dielectric media, the model also shows promise for determining the time- and position-dependent electron evolution induced by ultrashort laser pulses. Another interesting result is that the maximum electron density formed during femtosecond-laser-induced optical breakdown can exceed the conventional limit imposed by the plasma frequency.
APA, Harvard, Vancouver, ISO, and other styles
6

Longbiao, Li. "Temperature-Dependent Fatigue Damage Evolution of Fiber-Reinforced Ceramic-Matrix Composites." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14144.

Full text
Abstract:
Abstract In this paper, the temperature-dependent fatigue damage evolution of fiber-reinforced ceramic-matrix composites (CMCs) is investigated. The fatigue loading/unloading constitutive model considering the effect of temperature is developed based on the damage mechanisms of matrix cracking, interface debonding, and repeated sliding between the fiber and the matrix. The relationships between the fatigue loading/unloading hysteresis loops, testing temperature, applied cycle number, peak stress, and fiber/matrix interface debonding and sliding are established. The evolution of fatigue loading/unloading hysteresis loops, interface debonding and sliding length with applied cycle number is analyzed. The effects of temperature, peak stress level, applied cycle number, interface shear stress, and interface debonding energy on the fatigue damage evolution are discussed based on the developed temperature-dependent fatigue loading/unloading constitutive model. The experimental fatigue damage evolution of SiC/SiC composite at 600°C, 800°C, and 1000°C in inert atmosphere, 1000°C in air and in steam atmosphere, and 1300°C in air atmosphere are predicted. The interface shear stress of SiC/SiC composite decreases with temperature, and the degradation rate of interface shear stress increases with temperature.
APA, Harvard, Vancouver, ISO, and other styles
7

Gori, Fabio. "Preliminary Results for Forecasting the Oil Price Evolution With Negative Inflation Rate." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-86729.

Full text
Abstract:
Mass conservation equation is employed to study the time evolution of the mass of oil remaining in a reservoir, according to the mass flow rate of extraction, and to define the critical mass flow rate of extraction, which is the value exhausting the reservoir in an infinite time. The price evolution with time of the resource sold to the market is investigated in case of no-accumulation and no-depletion of the resources; i.e. when the resources are extracted and sold to the market at the same mass flow rate. The energy conservation equation is transformed into an energy-capital conservation equation, which allows to study the oil price evolution with time, dependent on the following parameters. The parameter PIFE, “Price Increase Factor of Extracted resource”, is the difference between the basic interest rate of the capital, e.g. inflation rate, and the mass flow rate of extraction. The parameter PIFS, “Price Increase Factor of Sold resource”, is the difference between the interest rate of the capital, e.g. prime rate, and the mass flow rate of extraction. The parameter CIPS, “Critical Initial Price of Sold resource”, depends on the initial price of the extracted resource, the interest rate of non-extracted resource, and the difference between PIFS and PIFE. The parameter CIPES, “Critical Initial Price Extreme of Sold resource”, depends on the initial price of the extracted resource, the interest rate of non-extracted resource, and PIFS. The present theory is applied to the time evolution of the oil price during the years following the economic crisis of 2008, introducing the new category of cases with a negative inflation rate, that was registered during 2009. The present theory can be applied also to the months with negative inflation rate with a reasonable fair agreement.
APA, Harvard, Vancouver, ISO, and other styles
8

Chen, Lei, Yan Du, Nicol E. McGruer, and George G. Adams. "Ductile Separation and Its Role in the Evolution of Gold Contacts." In ASME/STLE 2007 International Joint Tribology Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ijtc2007-44152.

Full text
Abstract:
In this paper, we study the role of ductile separation on the evolution of gold-on-gold micro-contacts. A specially designed SPM contact test station has been used to conduct the cycling tests. The evolution of contacts is studied by monitoring the characteristics of the pull-off force. The magnitude of the pull-off force, the force vs. displacement curves, and the rate-dependent pull-off force are sampled during cycling. It is found that ductile separation causes significant and random modification of the contact surfaces. The magnitude of the pull-off force also changes due to the variation of surface morphology. Significant plastic deformation during ductile separation can form a plateau region in the force-displacement curve which is characteristic of ductile separation. This deformation can also contribute to a higher pull-off force when the contacts are cycled at 300Hz compared with cycling at 0.5Hz. The difference between these rate-dependent pull-off forces can be used to indicate the degree of plastic dissipation during each separation.
APA, Harvard, Vancouver, ISO, and other styles
9

Yang, X. J., C. L. Chow, and K. J. Lau. "A Unified Viscoplastic Fatigue Damage Model for 63Sn-37Pb Solder Alloy Under Cyclic Stress Control." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32862.

Full text
Abstract:
A damage coupling viscoplastic model is developed to predict fatigue life of solder alloy 63Sn-37Pb under stress control. The viscoplastic flow rule chosen employs a hyperbolic sine function. A damage evolution equation is formulated based on three distinct material deformation behaviors: (i) stress rate independent damage evolution; (ii) stress rate dependent cyclic damage evolution; and (iii) stress rate dependent ductile damage evolution. The cyclic stress testing with different stress waveforms was first conducted to investigate their progressive viscoplastic deformations of the solder alloy. The investigation reveals that the material constants used in the model can be adequately determined from the results of standard creep tests. The constitutive model is validated by comparing the predicted and measured ratchetting results of the solder alloy under different forms of stress cycling. The proposed model is found to be capable of satisfactorily describing the viscoplastic deformation and ratchetting failure behaviors of the solder alloy under the conditions of the cyclic stress loading.
APA, Harvard, Vancouver, ISO, and other styles
10

Lu, J. F., X. F. Peng, and B. Bourouga. "Nucleation Kinetics for Boiling in Microstructures." In ASME 2005 Summer Heat Transfer Conference collocated with the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems. ASMEDC, 2005. http://dx.doi.org/10.1115/ht2005-72700.

Full text
Abstract:
Theoretical investigation is conducted to understand the bubble nucleation process in microstructures. The bubble evolution in microstructures is investigated for momentum conservation, and the evolution rate is deeply dependent on the structure. According to different dynamic characteristics in the region close to the critical radius, the nucleation process is divided into two stages. Based on the characteristics of these two stages, a nucleation kinetic equation is modified from classical theory and then is conducted to understand the special bubble nucleation process. The result concludes that the nucleation rate will be deduced if bubble evolution is restrained in microstructures.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography