A general phase-field model for simulating impact-sliding …
The paper is organized as follows. The impact-sliding point/line contact model, analyzing the transient dynamic response of the impact-sliding contact micro-area, is outlined in Section 2.In Section 3, a general thermo-elasto-plastic phase-field model is proposed, demonstrating its capability to predict various failure modes such as brittle …
The Impact of COVID-19 Zoo Closures on Behavioural and …
This study sought to understand the impact of facility closures and subsequent reopenings on behavioural and physiological parameters of welfare in four primate species housed in the UK: bonobos (Pan paniscus) (n = 8), chimpanzees (Pan troglodytes) (n = 11), and western lowland gorillas (Gorilla gorilla gorilla) (n = 6) held at …
Optimizing Model Parameters — PyTorch Tutorials …
Hyperparameters are adjustable parameters that let you control the model optimization process. Different hyperparameter values can impact model training and convergence rates (read more about hyperparameter tuning) We define the following hyperparameters for training: Number of Epochs - the number times to iterate over the dataset
Mathematical modeling and parameter estimation of …
6. Numerical simulation. Our numerical experiments are based on the simulation of the solution of the nonlinear Unemployment model (2).We are concerned in the case when the values of the basic reproduction number R (ϵ) > 1.This case study is chosen to ensure that the positive equilibrium Q ∗ exists and exhibits the local …
Numerical investigation of breaking waves impact on …
As presented in Fig. 14 to Fig. 16, it is obvious to distinguish impact types by instantaneous wave profiles as (a) broken waves at C1: the waves already break before the vertical wall and hit the wall with a chaotic and disorderly surface; (b) almost breaking at C4: plunging breaker entraps a small air pocket and (c) non-breaking at C6: the ...
A high-precision transient state prediction framework for …
The parameter identification, as presented in Sections 1 Introduction, 2 Refined HPS model, 3 Two-stage parameter identification strategy and parameter impact quantification, aims to search for an optimal combination of uncertain parameters associated with HGU systems and pipelines, ensuring the precise and robust prediction …
Estimation and Impact Assessment of Input and Parameter …
Simulation of spatially distributed monthly groundwater recharge: Spatially distributed monthly groundwater recharge was simulated using the WetSpass-M model (Abdollahi et al., 2017; Batelaan & De Smedt, 2007) as explained in section 2.4.1. Spatial variability is taken into account during the groundwater recharge simulation, and spatial …
The Impact of Policy and Technology Parameters on the Economics …
Throughout the developing world, most remote and isolated communities are still without reliable electricity in the twenty-first century, and this is primarily due to the high cost of grid extensions. In communities that do have electricity, they usually rely on diesel generators, though these have high operating and maintenance costs, while also …
Ranking environmental degradation trends of plastic marine
Accumulation of micro and nano-plastic in the oceans has emerged as a global challenge. Here, the authors predict a hierarchy of features that regulate their degradation and surface erosion by a ...
Discrete element modelling (DEM) input parameters
size k and S is a parameter sensitivity matrix of size nm×k [33]. Low sensitivity parameters can be systematically iden-tified as low importance parameters in the model by this analysis process [34,35]. Cross correlation between para-meters, which impedes reliable parameter estimates, is also assessed with these methods [36].
An interface constitutive model of plastic …
The JH2 constitutive model is further optimized on the basis of the HJC model, and three parameters are added on the basis of the 17 parameters of the HJC model, ... The concrete around the bullet hole was broken, but the damage area on the impact surface was still greater than that on the back surface, and there was still no phenomenon of ...
Validation of a particle impact breakage model …
The impact breakage model is implemented in a DEM-PBM coupling framework. Limitation and extension of the breakage model are stressed for the future study. Nomenclature …
Title: Impact of theoretical uncertainties on model parameter
Different computational techniques for cosmological phase transition parameters can impact the Gravitational Wave (GW) spectra predicted in a given particle physics model. To scrutinize the importance of this effect, we perform large-scale parameter scans of the dynamical real-singlet extended Standard Model using three …
Hyperparameter Optimization in Machine Learning Models
Machine learning involves predicting and classifying data and to do so, you employ various machine learning models according to the dataset. Machine learning models are parameterized so that their behavior can be tuned for a given problem. These models can have many parameters and finding the best combination of parameters can be treated …
Why did the English and Powhatan go to war in 1622?
By 1622, the paramount chief Powhatan and Pocahontas were dead, and the English had spread deep into Powhatan territory. The English forced the Powhatan Indians to move inland away from their traditional river valley homes. Native leaders under Opechancanough, Powhatan's half-brother and successor, had privately adopted a …
Exploring effective TET through a vibro-impact nonlinear …
In order to gain further insights into the underlying mechanism for the effective TET through VINES for η between 0.04 and 0.06 in Fig. 2 (a) and above 0.08 in Fig. 2 (b), a bifurcation analysis is carried out as shown in Fig. 3. Fig. 3 (a) and (b) show the bifurcation diagram for the relative velocity w ̇ i (= z ̇ m, i − z ̇ b, i) at impacts as a function of the …
A breakage model for particulate solids under impact loading
This gives [6] (40) N 0 = 100 exp − v c m where v is the impact velocity; c is a fitting parameter and m is termed the Weibull modulus. The fitting value of c and m …
Parameter Calibration and Optimization of a …
To improve the accuracy of simulation parameters used in discrete element simulation tests for the transplanting operation of the transplanting machine and to facilitate further optimization of crucial …
Validation of a model for impact breakage incorporating particle size
The averaged R 2 values show that both models fit the data well. The R 2 value for the JKMRC prior art model (R 2 = 0.988) appears slightly better than the new model (R 2 = 0.984), but the differences are not statistically significant. The JKMRC prior art model, however, was fitted to each individual size, i.e. each size having its own …
Vibration mechanism and improved phenomenological …
tosis deconvolution (MCKD) to enhance its impact characteristics. The results show that the phase between the fault impact and its adjacent meshing impact is consistent with the pro-posed assisted phase. Finally, the correctness of the vibration mechanism and the improved phenomenological model are verified experimentally. 1. Introduction
Scale-up procedure of parameter estimation in selection and …
The breakage function indicates the size evolution of broken particles resulting from impact loading. A summary of some common breakage functions was …
Analysis of Rock Breaking Parameters and Simulation of …
With the continuous development of high-pressure water jet technology, research on the optimization of structural parameters for multi-nozzle configurations, the perforation effect of jet rotational impact rock breaking, and the impact force during rock breaking has received increasing attention. Through the development of a self-designed …
Powhatan Uprising of 1622
So began the Powhatan Uprising of March 22, 1622, which claimed the lives of approximately 347 colonists and came perilously close to extinguishing England's most promising outpost in North America. ... Because the Indian uprising had such an important impact on English colonization and Anglo-Powhatan relations, historians have …
Impact of a change in the parameter in the SVI/gSVI/IVP model.
Added to this antagonistic change in the point of the markets models in algorithmic trading, we have been witnessing an interesting re-balancing shift between models and data.
Mechanism of surrounding rock failure in impact stress and …
2.1 Transient unloading model under in-situ stress. When excavating a circular tunnel at a large depth in rock mass, the in-situ stress is uniformly distributed. To …
The Ogden model of rubber mechanics: 50 years of impact …
Performance of the three-term (six parameters) Ogden model (continuous curves) at modelling the mechanical response of rubber (circles) . (a–c) Fitting the 1944 data of Treloar, (a) of simple tension, (b) of pure shear and (c) of equibiaxial tension. Comparisons with the new-Hookean and Mooney–Rivlin models (broken lines) are shown.
Rock Fragmentation Size Distribution Prediction and Blasting …
Rock fragmentation size distribution is often used as an important index to account for the blasting effect because it directly affects the subsequent loading, …
Bayesian calibration of strength model parameters from Taylor impact
This approach essentially accounts for the displacement of material particles located at positions P 1 and P 2 and relates their final location with the strength model parameters. Although incorporating more points along the profile may help further inform the calibration, we will see that reasonable fits to the entire profile are attainable through …
Induction motor modeling of broken rotor bars and …
The parameters Rs, Lf and Lr are respectively the stator resistance, the global leakage inductance referred to the stator and the rotor inductance. B. Rotor It is assumed that the rotor cage can ...
Simulation Analysis of Igneous Rock Breaking Law Under Cut …
The optimal impact parameters of Igneous rock broken by these cutters were obtained, which were 600 N and 200 Hz, 900 N and 300 Hz, 600 N and 300 Hz …