Penetration Model Research Articles

Finite Boundary Conditions Due to the Bar Presence in the Model of Chloride Penetration.

The chloride penetration is usually modelled through the application of a solution of Fick’s second law of diffusion, based on the assumption of semi-infinite boundary conditions. However, the presence of the bars, on whose surface the chlorides accumulate, makes this assumption incorrect. As the time progresses, the chlorides in the steel/concrete interface increase in concentration more than the chlorides overpassing the bar position without obstacles. This circumstance, although previously studied, has not been introduced in common practice, in spite of it supposes early reaching of the chloride threshold. The study in this paper shows a deterministic analysis of the chloride diffusion process by the finite element method (FEM) which numerically solves Fick’s second law, taking into account the accumulation of the chlorides on the bar surface. Several examples are calculated and factors between the finite/semi-infinite solutions are given. These factors depend on the cover depth and the diffusion coefficient, and with less importance, on the diameter of the bar, which make it unfeasible to propose a general trend.

Experimental and Analytical Study on the Penetration Depth of Mortar Targets Subjected to Projectile Impact in the Hypervelocity Regime

A projectile may be deformed and eroded due to the high pressure generated by hypervelocity penetration, which makes it difficult to describe the penetration mechanism for protection engineering by existing theories at such high velocities. To analyze the penetration depth of concrete-like targets subjected to hypervelocity impact by kinetic energy weapons, experiments with ogive-nosed steel projectiles penetrating mortar targets are conducted, where the average uniaxial compressive strength of the mortar targets is 41.8[Formula: see text]MPa and the impact velocities range from 1[Formula: see text]225[Formula: see text]m/s to 2[Formula: see text]392[Formula: see text]m/s. The experimental results show that the crater diameter and crater depth have a linear relationship with the striking velocity. The depth of penetration (DOP) increases linearly first and then decreases sharply and increases slowly again. Three penetration regimes are observed in turn with increasing velocity, i.e. rigid projectile penetration, abrasive projectile penetration and semifluid projectile penetration. Furthermore, based on a study of the dynamic compression behavior and penetration resistance function of concrete, a hydroelastoplastic-frictional penetration model is established. The velocity range is divided into solid penetration, semifluid penetration and fluid penetration, which correspond to [Formula: see text], [Formula: see text] and [Formula: see text], respectively. Then, the rigid and abrasive projectile penetration models, which consider the projectile mass loss, are verified by the present test data. Finally, the semifluid projectile penetration model is evaluated with the existing test data. These results can provide support for research on the damage effect of hypervelocity kinetic energy weapons and the design of underground strategic protection engineering.

Radiant heating rate associated with chlorophyll dynamics in upper ocean of Southern Bay of Bengal: A case study during Bay of Bengal Boundary Layer Experiment

A 11-day time series of optical, physical and biological observations were collected from the southern Bay of Bengal during the summer monsoon of 2016 as a part Bay of Bengal Boundary Layer Experiment (BoBBLE). These observations were used to estimate Radiative Heating Rate (RHR) and to further understand its dependence on biological and physical variables. Initially, the water column was characterized by an oligotrophic condition with weak surface chlorophyll (chl-a) concentration (<0.1 mg m-3). During this period, the sky was clear, mixed layer was shallow and RHR reached up to 0.14 °C hr-1. Subsequently, the mixed layer deepened (60–70 m) and the surface chl-a concentration increased to 0.4 mg m-3. However, the sky was relatively cloudy (cloud index = 32%) and the RHR reduced to 0.01 °C hr-1 owing to reduced solar incidence. The observations suggest that the combined effect of physical and biological factors determine the RHR in the water column. A one-dimensional light penetration model simulations showed that the biological heating of 10 W m-2 would generate additional heating of 0.008 °C hr-1 in the upper ocean indicating significant impact of elevated chl-a concentration. These improved understanding of biophysical interaction in the Bay of Bengal will help to improve our knowledge about the chl-a induced feedbacks on sea surface temperature.

Systematic application of the M3Y NN forces for describing the capture process in heavy-ion collisions involving deformed target nuclei

We present results of a systematic study of the capture process through the barrier penetration model. The nucleus-nucleus interaction potential is calculated using the double-folding model (DFM) with the M3Y Paris $\mathit{NN}$ forces. The nucleon densities entering the model are generated from the experimental three-parameter Fermi charge densities. The DFM has been extended to the case of deformed target nuclei. It is shown that the density-dependent M3Y $\mathit{NN}$ forces with the finite range exchange part can be mimicked successfully by the zero-range density-independent forces. The latter option significantly reduces the required computer time. For the nucleon densities and target nuclei deformations, we employ the values from the commonly used data bases. Thus, we do not vary any parameters to reach a better agreement with the data. The resulting cross sections are compared with data for 20 reactions with the product of the charge numbers ${Z}_{P}{Z}_{T}$ ranging from 216 up to 2576. We discuss the opinion met in the literature that the M3Y $\mathit{NN}$ forces provide a poorer description of the capture cross sections in heavy-ion collisions in comparison to the $\mathit{NN}$ forces coming from the relativistic mean-field approach. Our calculations show that the M3Y $\mathit{NN}$ forces give an agreement with the data which is not perfect yet is not worse than the one resulting from the relativistic mean-field approach $\mathit{NN}$ forces.

Mass transfer kinetics and process optimization of osmotic dehydration of Kinnow mandarin ( Citrus reticulata ) peel

Kinnow mandarin (Citrus reticulata) peel, an agricultural solid waste of the Kinnow juice processing industry, was studied to understand the mass transfer kinetics during osmotic dehydration and its process optimization. The experiments were conducted in sucrose (40, 50, and 60° Brix) at different temperatures of 40, 50, and 60°C and process duration of 0–240 min. The Central Composite Design was used for the optimization of the osmotic dehydration process with the variables, such as blanching time (3–6 min), solute concentration (40–60° Brix), process temperature (40–60°C), and process duration (120–150 min). Increased water loss (28.70 g/100 g) and solid gain (12.90 g/100 g) were observed at 60° Brix and 50°C in 240 min. The Penetration model was the best-fitted model for water loss and solute gain. The osmotic dehydration process at 60° Brix and 48°C for 150 min with blanching (3.60 min) yielded water loss (32.40 g/100 g), solute gain (14.60 g/100 g), ascorbic acid (17.50 mg/100 g), and overall acceptability (6.50). Overall, the findings concluded that the understanding of process parameters can be used as the basis for the sustainable valorization of Kinnow peel using osmotic dehydration. Practical applications Currently, valorization of agri-food waste becomes a major challenge and thus we studied to understand the mass transfer kinetics during the osmotic dehydration and its process optimization of Kinnow mandarin (Citrus reticulata) peel. The findings suggested that the optimization of osmotic dehydration process parameters and kinetic modeling may be useful for the valorization of Kinnow peel in the development of food products.

Damage characteristics and failure modes of concrete gravity dams subjected to penetration and explosion

In recent decades, the penetration depth, hit accuracy, and damage ability of earth-penetrating weapons have been greatly improved. High dams will thus face increasingly severe threats of penetration and explosion from such weapons. The nonlinear dynamic responses and failure processes of dams under the combined action of penetration and explosion are much more complicated than those under static or seismic loadings, and they are yet more complex than those under air blasts or underwater explosion loads. There have been various comprehensive numerical investigations of concrete gravity dams subjected to underwater explosions; however, there have been few such investigations considering penetration and explosion. In this study, the damage characteristics and failure modes of a concrete gravity dam subjected to the combined action of penetration and explosion are examined. A fully coupled Lagrangian–Eulerian approach is adopted to describe the nonlinear dynamic responses and damage processes of the dam, and this includes consideration of the dam–reservoir–foundation interactions. In this paper, the validities of the penetration model and internal explosion model are discussed by comparing results obtained from the proposed method with those obtained from empirical formulas and experimental tests. The penetration characteristics of the concrete gravity dam subjected to impact by high-velocity projectiles are presented. The damage development processes and nonlinear dynamic responses of the dam to an internal explosion with and without consideration of the initial penetration damage are compared. The failure modes of the dam resulting from different penetration and explosion conditions are categorized. The penetration depths of different explosives resulting in the greatest damage range are obtained. The results show that although the initial penetration increases the degree of damage to the dam, it has little impact on the failure mode of the dam. The failure modes can be divided into two categories: a blasting funnel at the surface and an internal ellipsoidal explosion. The adverse penetration depth resulting in the greatest damage range is found to increase nonlinearly with increasing explosive weight.

Generalized phenomenological model for the magnetic field penetration and magnetization hysteresis loops of a type-II superconductor

A generalized phenomenological model for the critical state of type-II superconductors with magnetic field parallel to the superconducting plate is proposed. This model considers the global magnetization including both the equilibrium magnetization from surface screening current and the non-equilibrium magnetization from bulk pinning in a self-consistent way. Our model can be used to simulate the magnetization-hysteresis-loops (MHLs) and flux penetrating process of different type-II superconductors, from low- to high-kappa values. Here we take an optimally doped Ba0.6K0.4Fe2As2 single crystal as a testing example. The model can fit the data quite well and several important parameters can be extracted from the fitting. Thus, the model can be extended to a general case for studying the magnetization and flux penetration in other type-II superconductors.

Investigating and modeling the effect of light intensity on Rhodopseudomonas palustris growth.

Photosynthetic bacteria can be useful biotechnological tools-they produce a variety of valuable products, including high purity hydrogen, and can simultaneously treat recalcitrant wastewaters. However, while photobioreactors have been designed and modeled for photosynthetic algae and cyanobacteria, there has been less work on understanding the effect of light in photosynthetic bacterial fermentations. To design photobioreactors, and processes using these organisms, robust models of light penetration, utilization, and conversion are needed. This stydy uses experimental data from a tubular photobioreactor designed to focus in on light intensity effects, to model the effect of light intensity on the growth of Rhodopseudomonas palustris, a model photosynthetic bacterium. The work demonstrates that growth is controlled by light intensity, and that this organism does experience photolimitation below 200 W/m2 and photoinhibition above 600 W/m2 . This has implications for outdoor applications, as there will be low growth during the periods of limited light, and growth may be inhibited during the light intensive hours of mid-day. Further, the work presents a model for light penetration in cylindrical photobioreactors, which tends to be the most common geometry. The model developed showed good fit to the experimental data for each light intensity investigated, with high R2 values and NRMSE values all below 20%. The work extends the modeling tools for these organisms, and will allow for better photobioreactor design, and the integration of modeling tools in designing processes which use photosynthetic bacteria.

Dry Snow Parameter Retrieval With Ground-Based Single-Pass Synthetic Aperture Radar Interferometry

In this article, we investigate the potential of using single-pass InSAR model-based approaches to retrieve dry snow parameters. Two InSAR scattering models of dry snow are considered: the dense-medium random volume over ground (RVoG) model and the simple variant of the full penetration (FP) model. A quasi-crystalline approximation (QCA)-based extinction analysis confirms the negligible extinction dependence of the InSAR observables at L/C/X-band for fresh dry snow. The FP models the low-frequency (L/C/X-band) InSAR phase as a single constraint of snow depth and density, which can be supplemented by an extra observation (e.g., InSAR coherence or <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> depth/density). The single-pass InSAR models and inversion approaches were validated using X-band InSAR data collected from a tower-based three-frequency (X/Ku-low/Ku-high) fully polarimetric TomoSAR system, where a multi-frequency polarimetric InSAR analysis and ground-to-volume ratio-based snow condition analysis were conducted. We also analyzed the sensitivity and error propagation of the single-pass InSAR phase and coherence in measuring dry snow depth/density. It was found that the X-band HH-pol FP-modeled single-pass InSAR phase along with RVoG-modeled coherence or <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> depth is capable of measuring snow water equivalent (SWE) with a 23–26 mm uncertainty (13–15%) and a 20–26 mm bias (12–15%) for dry snow SWE of 0.2 m, and with an optimal perpendicular baseline on the order of a tenth of the snow depth (0.8 m) at our test site. This single-pass InSAR approach with the FP model is potentially useful and thus needs further investigation for large-scale dry snow retrieval with a wide range of snow conditions using ground-based/airborne/spaceborne low-frequency (L/C/X-band) InSAR observations.

CLPVG: Circular limited penetrable visibility graph as a new network model for time series.

A visibility graph transforms time series into graphs, facilitating signal processing by advanced graph data mining algorithms. In this paper, based on the classic limited penetrable visibility graph method, we propose a novel mapping method named circular limited penetrable visibility graph, which replaces the linear visibility line in limited penetrable visibility graph with nonlinear visibility arc for pursuing more flexible and reasonable mapping of time series. Tests on degree distribution and some common network features of the generated graphs from typical time series demonstrate that our circular limited penetrable visibility graph can effectively capture the important features of time series and show higher robust classification performance than the traditional limited penetrable visibility graph in the presence of noise. The experiments on real-world time-series datasets of radio and electroencephalogram signals also suggest that the structural features provided by a circular limited penetrable visibility graph, rather than a limited penetrable visibility graph, are more useful for time-series classification, leading to higher accuracy. This classification performance can be further enhanced through structural feature expansion by adopting subgraph networks. All of these results demonstrate the effectiveness of our circular limited penetrable visibility graph model.

Feasibility of neutral particle analysis for fast-ion measurements at W7-X

A preliminary study investigating capabilities of a planned but not yet installed neutral particle analyzer (NPA) [1,2] system combined with a diagnostic neutral beam at Wendelstein 7-X (W7-X) [3] is presented. Additionally two NPAs viewing the neutral beam injection (NBI) [4] source 8 beam and using it as neutral source are studied. The main focus is laid on what information about NBI fast-ion slowing down distributions can be inferred from active NPA measurements when altering the magnetic configuration, plasma β, density, electron temperature or radial electric field. For an order of magnitude estimation of the passive signal a model for penetration of neutral hydrogen recycling from the first wall is implemented. For the active signal a diagnostic neutral beam injector was simulated using FIDASIM [5]. The fast-ion slowing down distributions were calculated with ASCOT [6]. The synthetic NPA signal is found in general to be sensitive to changes in the fast-ion distribution function. Distinct features can be seen in the high energy active signal in the high-mirror configuration when changing β, especially, when looking at deeply trapped fast particles. However, for the initially planned installation geometry of the NPA diagnostic most fast-ion distributions exhibit only small differences in the magnitude and especially shape. In a high density case in the standard magnetic configuration with a central β of 8%, the fast-ion density in the core region is too low to provide a measurable flux of charge exchanged neutrals. The passive signal from the inner plasma regions is found to be negligible compared to the active signal.

Performance analysis of aqueous LiCl and CaCl2 based falling film dehumidifier with surface modification

• Analysis is carried out on a falling film based liquid desiccant dehumidifier. • The surface is modified with sinusoidal profile to increase the dehumidification. • The sinusoidal wavy profile increases the desiccant surface area by 7%. • Aqueous LiCl solution enhances the dehumidification by 29.15% compared to CaCl 2 . • With aqueous LiCl, the modified surface increases the dehumidification by 33.18%. In summer air-conditioning, conventional vapor compression systems cool the process air to its dew point temperature for dehumidification and further heat it to required supply temperature. This involves extra cooling and subsequent heating. Liquid desiccant systems avert this issue by separately handling latent and sensible loads, while running primarily on low grade thermal energy. Falling film type liquid desiccant dehumidifiers are advantageous over other types, mainly, as they reduce desiccant carryover into supply air stream. The current work aims towards the analysis and the performance improvement of a falling film type dehumidifier with the help of wavy profile of the working surface. Detailed comparison of the two commonly used desiccants, i.e., LiCl and CaCl 2 are carried out to analyse the performance of the dehumidifier. The present work also includes the characterisation of the wave profile and the analysis in terms of various important parameters, such as, the dehumidification effectiveness, the moisture removal rate and the change in specific humidity, missing in earlier studies. In order to study the performance, a simplified 2–D transient finite volume model is taken into consideration to simulate a multiphase, multi-component conjugate heat and mass transfer system using ANSYS Fluent 19.2. The volume of fluid method is used to trace out the liquid–gas interface. With back-end modification of the solver, the thermophysical properties of the liquid film are evaluated using empirical relationships, as a function of temperature and concentration. The penetration model of mass transfer provides the local mass transfer coefficients. The moisture removing the potential of the aqueous solutions of LiCl and CaCl 2 are evaluated at quasi steady-state conditions. The numerical solver is validated with the already published experimental results with a maximum deviation of 10.31%. A sinusoidal wavy profile of the wall introduced in the system enhances the turbulence intensity by 3.8% and the dehumidification performance by 33.18% and 18% for LiCl and CaCl 2 , respectively. It is due to the enhanced liquid–gas interface area. The mean film thickness is found to improve by 15.25% and 13.38% for LiCl and CaCl 2 , respectively. The effect of process parameters on the performance of the dehumidifier is also studied. It has been observed that the dehumidification effectiveness decreases from 86.14% to 31.1% with increase in inlet air velocity from 0.2 m/s to 2.0 m/s. It has also been found that a lower concentration of the desiccant solution and lower velocity of air yield higher dehumidification effectiveness. However, the moisture removal rate of the system will be compromised. Compared to the previously studied cases, the current configuration of the sinusoidal profile with amplitude to wavelength ratio of 1:15, yields superior dehumidification performance.

Fatores que afetam a modelagem probabilística da vida útil de estruturas de concreto armado expostas a ambientes marinhos

Abstract Concrete durability design has received increasing importance recently, with specifications moving from prescriptive to performance based. In performance-based approaches, it is essential to evaluate and calibrate service life models capable of reliably representing the phenomenon that triggers the degradation process. This paper aims to discuss the main concepts related to the probabilistic service life modeling of reinforced concrete structures under chloride environments, considering the application of different prediction models. Through numerical analysis, parametric differences among chloride penetration models are evidenced, and the results, their variability, and the admitted failure conditions are analyzed. An overview of the current scenario of the durability design of concrete structures is presented. Aspects associated with characteristic service life, the definitions of durability limit states, and their respective target failure probabilities are discussed.

Lean start-up in market penetration using DMADV methodology: An empirical study

Prior research has reported that new product development can integrate product design, marketing inputs, and supplier performance. Yet, our knowledge of the startup stabilization process is minimal. Hence, the present study empirically investigates how an Indian tech giant attempts a new product development in the market penetration category. In this context, the current investigation proposes an implementation strategy using lean-six sigma philosophy, i.e., Define-Measure-Analyze-Design-Validate (DMADV) methodology. The new product considered for the current study belongs to the existing market - existing product, i.e., mobile surveillance devices in the Indian market. The lean tools used in the present investigation are Project charter, brainstorming, voice of customer, market analysis, benchmarking, quality function deployment, and system diagram. Our study reveals critical implementation insights about the market penetration model for lean startups and underscores its significance. Furthermore, a cost gap of 94 US$ of the product manufacturing cost with the lowest available model price is reported. The findings inferred from the present study help entrepreneurs to stabilize their startups effectively using lean philosophy. The potential readership for this study is entrepreneurs, management graduates, and industrial management teams.

Numerical simulation of anti-penetration performance of corrugated plate/aluminum foam sandwich structure

In order to study the anti-penetration performance of corrugated plate/aluminum foam composite sandwich structure, LS-DYNA software was used to simulate. The penetration model of 7.62 mm rifle bullet into the sandwich structure was established, and the residual velocities of bullets at five penetration positions were compared and analyzed. The influence of different initial velocity forward penetration and initial velocity 900m/s angle penetration on B is focused. The results show that at different penetration positions, the residual velocity of bullet B is the largest and the anti-penetration performance is the weakest. With the decrease of the initial velocity of the bullet, the movement of the bullet in the structure is different, and the deflection phenomenon occurs when the bullet is penetrating B. When different penetration angles (initial velocity 900m/s) penetrate B, the trajectory of the bullet is approximately a straight line along the penetration angle. When the penetration angle is 30°, it cannot completely penetrate the sandwich structure. The deformation of sandwich structure is mainly shear deformation; under different conditions, the bullet runs through the sandwich structure only at the initial speed of 900 m/s. This study can provide basis and reference for the improvement and application of corrugated plate/aluminum foam composite sandwich structure.

Modeling of Grouting Penetration in Porous Medium with Influence of Grain Distribution and Grout–Water Interaction

In this study, a numerical model of grouting penetration in a porous medium is established. The fluid flow in the interstices of the porous medium is directly modeled by Navier–Stokes equations. The grouting process is considered as a two-phase flow problem, and the level set method is used to characterize the interaction between grout and groundwater. The proposed model has considered the nuances for each grain during grouting penetration, instead of representing the fluid flow as a continuum process. In the simulation, three kinds of porosity (0.3; 0.4; 0.5) and two kinds of grain size distribution (0.5~1 mm; 1~2 mm) are used. Results show that: the pressure drop along penetration distance is approximately in a linear trend. The variation of filling degree along grouting distance approximately obeys a quadratic polynomial function. The injection pressure is influenced by the porosity and grain size of the porous medium, especially by the former. A theoretical analysis is carried out to propose an analytical solution of the grouting penetration. The analytical solution gives a good estimation when the grain amounts in the porous medium are small, and the difference becomes larger as the grain amounts increase.

Large-Scale Evaluation of Collision Cross Sections to Investigate Blood-Brain Barrier Permeation of Drugs.

Successful drug administration to the central nervous system requires accurate adjustment of the drugs’ molecular properties. Therefore, structure-derived descriptors of potential brain therapeutic agents are essential for an early evaluation of pharmacokinetics during drug development. The collision cross section (CCS) of molecules was recently introduced as a novel measurable parameter to describe blood-brain barrier (BBB) permeation. This descriptor combines molecular information about mass, structure, volume, branching and flexibility. As these chemical properties are known to influence cerebral pharmacokinetics, CCS determination of new drug candidates may provide important additional spatial information to support existing models of BBB penetration of drugs. Besides measuring CCS, calculation is also possible; but however, the reliability of computed CCS values for an evaluation of BBB permeation has not yet been fully investigated. In this work, prediction tools based on machine learning were used to compute CCS values of a large number of compounds listed in drug libraries as negative or positive with respect to brain penetration (BBB+ and BBB− compounds). Statistical evaluation of computed CCS and several other descriptors could prove the high value of CCS. Further, CCS-deduced maximum molecular size of BBB+ drugs matched the dimensions of BBB pores. A threshold for transcellular penetration and possible permeation through pore-like openings of cellular tight-junctions is suggested. In sum, CCS evaluation with modern in silico tools shows high potential for its use in the drug development process.

Unconventional Reaction Phase Diagram for the Penetration Etching/Growth of Graphene Adlayers

Cu has shown an advantage in growing monolayer graphene due to the very low C solubility and surface-mediated self-limiting growth, which hinders the growth of multilayer graphene. This work reports an unconventional penetration etching/growth of graphene adlayers tuned by oxygen beyond the self-limiting growth, supported by the C isotope labeling results. The effect of oxygen is nonmonotonic, i.e., with the increase of oxygen, graphene adlayers are etched without damaging the top layer, then shift to growth, and finally, all layers are etched. In addition, the reaction did not seem to reach equilibrium in the time range of the experiment but continued as if oxygen was increasing with respect to time. An oxygen-assisted exchange penetration model is proposed to interpret the growth mechanism. Oxygen etches the top shield layer, which is simultaneously healed by consuming the C species around adlayers and results in adlayer decomposition due to the break of equilibrium. Additionally, oxygen assists penetration of C from the gaseous agents into the shield layer for adlayer growth. The domination of one over the other depends on the concentration of oxygen, resulting in overall etching or growth. Finally, the synthesis of large-area monolayer and bilayer graphene films with good uniformity is demonstrated.

A Mechanistic Bayesian Inferential Workflow for Estimation of In Vivo Skin Permeation from In Vitro Measurements

Computational models can play an integral role in the chemical risk assessment of dermatological products. However, a limitation on the ability of mathematical models to extrapolate from in vitro measurements to in human predictions arises from context-dependence: modeling assumptions made in one setting may not carry over to another scenario. Mechanistic models of dermal absorption relate the skin penetration kinetics of permeants to their partitioning and diffusion across elementary sub-compartments of the skin. This endows them with a flexibility through which specific model components can be adjusted to better reflect dermal absorption in contexts that differ from the in vitro setting, while keeping fixed any context-invariant parameters that remain unchanged in the two scenarios. This paper presents a workflow for predicting in vivo dermal absorption by integrating a mechanistic model of skin penetration with in vitro permeation test (IVPT) measurements. A Bayesian approach is adopted to infer a joint posterior distribution of context-invariant model parameters. By populating the model with samples of context-invariant parameters from this distribution and adjusting context-dependent parameters to suit the in vivo setting, simulations of the model yield estimates of the likely range of in vivo dermal absorption given the IVPT data. This workflow is applied to five compounds previously tested in vivo. In each case, the range of in vivo predictions encompassed the range observed experimentally. These studies demonstrate that the proposed workflow enables the derivation of mechanistically derived upper bounds on dermal absorption for the purposes of chemical risk assessment.

Numerical investigation of inside peak particle velocities for predicting the vibration influence radius of vibratory pile driving

The vibration influence radius of vibratory pile driving is commonly predicted by the peak particle velocity (PPV) at the ground surface rather than inside the soil. In this paper, a vibratory penetration model is established in FLAC3D to investigate both surface and inside PPVs. The computation time of the model is significantly decreased by a density scaling method. The surface PPV attenuation in simulation shows a good agreement with a field test. When the distance from the pile axis is identical, the maximum PPV is inside the soil rather than at the ground surface. Then, the PPV at all points are illustrated as an isoline map, where the inside vibration influence radius is larger than that of surface. Additionally, the inside influence radius is still bigger as two construction parameters (the centrifugal force and the static force) change. The centrifugal force can slightly increase the inside influence radius and the static force has little effect on the radius. This work could advance vibration measurements for predicting the influence radius of vibratory pile driving.