scholarly journals Evaluation and Validation of a Joint Stress Test to Induce Activity-Related Knee Joint Discomfort — a Prospective Case-Control Study

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Christiane Schön ◽  
Claudia Reule ◽  
Katharina Knaub ◽  
Antje Micka ◽  
Manfred Wilhelm ◽  
...  
Keyword(s):  
Knee Joint ◽  
Healthy Subjects ◽  
Stress Test ◽  
Osteoarthritis Of The Knee ◽  
Time Interval ◽  
Short Time Interval ◽  
Joint Stress ◽  
Joint Health ◽  
The Impact ◽  
Health Function

Abstract Background The assessment of improvement or maintenance of joint health in healthy subjects is a great challenge. The aim of the study was the evaluation of a joint stress test to assess joint discomfort in subjects with activity-related knee joint discomfort (ArJD). Results Forty-five subjects were recruited to perform the single-leg-step-down (SLSD) test (15 subjects per group). Subjects with ArJD of the knee (age 22–62 years) were compared to healthy subjects (age 24–59 years) with no knee joint discomfort during daily life sporting activity and to subjects with mild-to-moderate osteoarthritis of the knee joint (OA, Kellgren score 2–3, age 42–64 years). The subjects performed the SLSD test with two different protocols: (I) standardization for knee joint discomfort; (II) standardization for load on the knee joint. In addition, range of motion (ROM), reach test, acute pain at rest and after a single-leg squat and knee injury, and osteoarthritis outcome score (KOOS) were assessed. In OA and ArJD subjects, knee joint discomfort could be reproducibly induced in a short time interval of less than 10 min (200 steps). In healthy subjects, no pain was recorded. A clear differentiation between study groups was observed with the SLSD test (maximal step number) as well as KOOS questionnaire, ROM, and reach test. In addition, a moderate to good intra-class correlation was shown for the investigated outcomes. Conclusions These results suggest the SLSD test is a reliable tool for the assessment of knee joint health function in ArJD and OA subjects to study the improvements in their activities. Further, this model can be used as a stress model in intervention studies to study the impact of stress on knee joint health function.

NUMERICAL STUDY OF THE STATE OF SOIL DAMS AS A RESULT OF IMPACT OF SHOCK WAVES AND UNSTEADY LOADS

2021 ◽  
pp. 55-62
Author(s):  
E. V. ANDREEV ◽  
Keyword(s):  
Shock Waves ◽  
Numerical Study ◽  
Pressure Head ◽  
Operational Reliability ◽  
Hydraulic Structures ◽  
Time Interval ◽  
Short Time Interval ◽  
Urgent Task ◽  
Temperature Dependences ◽  
The Impact

At the stage of the life cycle, ensuring the operational reliability and safety of pressure head hydraulic structures is an urgent task. One of the serious threats at the present stage is the destruction of hydraulic structures by the impact of non-stationary loads, by directed explosions in the immediate vicinity of the structures or on their surface. Shock waves pose a serious threat to hydraulic structures. Impulse short-term impact on the solid surfaces of hydraulic structures or on the aquatic environment characterizes the specifi cs of the problem under consideration, as the nonstationary of the process of motion of continuous media into which, in a short time interval, a volume of energy can be released that can deform or completely destroy them. Scenarios of this kind can occur either in the immediate vicinity of a hydraulic structure or as a result of the collision of solid bodies on its surface. Water upstream of the hydro technical structure and its body is a complex liquid because many of its characteristics differ significantly in size from similar characteristics of other liquids or have so-called anomalies on pressure and temperature dependences.

scholarly journals Spatiotemporal variability of water vapor investigated using lidar and FTIR vertical soundings above the Zugspitze

2015 ◽  
Vol 15 (6) ◽  
pp. 3135-3148 ◽  
Author(s):  
H. Vogelmann ◽  
R. Sussmann ◽  
T. Trickl ◽  
A. Reichert
Keyword(s):  
Water Vapor ◽  
Spatiotemporal Variability ◽  
Time Interval ◽  
Short Time Interval ◽  
Horizontal Distance ◽  
Free Troposphere ◽  
Time Intervals ◽  
Matching Criteria ◽  
The Impact ◽  
Relative Variability

Abstract. Water vapor is the most important greenhouse gas and its spatiotemporal variability strongly exceeds that of all other greenhouse gases. However, this variability has hardly been studied quantitatively so far. We present an analysis of a 5-year period of water vapor measurements in the free troposphere above the Zugspitze (2962 m a.s.l., Germany). Our results are obtained from a combination of measurements of vertically integrated water vapor (IWV), recorded with a solar Fourier transform infrared (FTIR) spectrometer on the summit of the Zugspitze and of water vapor profiles recorded with the nearby differential absorption lidar (DIAL) at the Schneefernerhaus research station. The special geometrical arrangement of one zenith-viewing and one sun-pointing instrument and the temporal resolution of both instruments allow for an investigation of the spatiotemporal variability of IWV on a spatial scale of less than 1 km and on a timescale of less than 1 h. The standard deviation of differences between both instruments σIWV calculated for varied subsets of data serves as a measure of variability. The different subsets are based on various spatial and temporal matching criteria. Within a time interval of 20 min, the spatial variability becomes significant for horizontal distances above 2 km, but only in the warm season (σIWV =0.35 mm). However, it is not sensitive to the horizontal distance during the winter season. The variability of IWV within a time interval of 30 min peaks in July and August (σIWV > 0.55 mm, mean horizontal distance = 2.5 km) and has its minimum around midwinter (σIWV < 0.2 mm, mean distance > 5 km). The temporal variability of IWV is derived by selecting subsets of data from both instruments with optimal volume matching. For a short time interval of 5 min, the variability is 0.05 mm and increases to more than 0.5 mm for a time interval of 15 h. The profile variability of water vapor is determined by analyzing subsets of water vapor profiles recorded by the DIAL within time intervals from 1 to 5 h. For all altitudes, the variability increases with widened time intervals. The lowest relative variability is observed in the lower free troposphere around an altitude of 4.5 km. Above 5 km, the relative variability increases continuously up to the tropopause by about a factor of 3. Analysis of the covariance of the vertical variability reveals an enhanced variability of water vapor in the upper troposphere above 6 km. It is attributed to a more coherent flow of heterogeneous air masses, while the variability at lower altitudes is also driven by local atmospheric dynamics. By studying the short-term variability of vertical water vapor profiles recorded within a day, we come to the conclusion that the contribution of long-range transport and the advection of heterogeneous layer structures may exceed the impact of local convection by 1 order of magnitude even in the altitude range between 3 and 5 km.

scholarly journals Newborn screening for spinal muscular atrophy in Germany: clinical results after 2 years

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Katharina Vill ◽  
Oliver Schwartz ◽  
Astrid Blaschek ◽  
Dieter Gläser ◽  
Uta Nennstiel ◽  
...  
Keyword(s):  
Spinal Muscular Atrophy ◽  
Newborn Screening ◽  
Muscular Atrophy ◽  
Neurodevelopmental Outcome ◽  
Specific Treatment ◽  
Time Interval ◽  
Short Time Interval ◽  
Relevant Parameter ◽  
The Impact

Abstract Background Spinal muscular atrophy (SMA) is the most common neurodegenerative disease in childhood. Since motor neuron injury is usually not reversible, early diagnosis and treatment are essential to prevent major disability. Our objective was to assess the impact of genetic newborn screening for SMA on outcome. Methods We provided clinical data from 43 SMA patients, identified via polymerase chain reaction of the SMN1 gene from dried blood spots between January 2018 and January 2020 in Germany. Follow-up included neurophysiological examinations and standardized physiotherapeutic testing. Results Detection of SMA with newborn screening was consistent with known incidence in Germany. Birth prevalence was 1:6910; 39.5% had 2 SMN2 copies, 23% had 3 SMN2 copies, 32.5% had 4 copies, and 4.5% had 5 copies of the SMN2 gene. Treatment with SMA-specific medication could be started at the age of 14–39 days in 21 patients. Pre-symptomatically treated patients remained throughout asymptomatic within the observation period. 47% of patients with 2 SMN2 copies showed early, presumably intrauterine onset of disease. These patients reached motor milestones with delay; none of them developed respiratory symptoms. Untreated children with 2 SMN2 copies died. Untreated children with 3 SMN2 copies developed proximal weakness in their first year. In patients with ≥ 4 SMN2 copies, a follow-up strategy of “watchful waiting” was applied despite the fact that one of them was treated from the age of 6 months. Two infant siblings with 4 SMN2 copies were identified with a missed diagnosis of SMA type 3. Conclusion Identification of newborns with infantile SMA and prompt SMA-specific treatment substantially improves neurodevelopmental outcome, and we recommend implementation in the public newborn screening in countries where therapy is available. Electrophysiology is a relevant parameter to support the urgency of therapy. There has to be a short time interval between a positive screening result and referral to a therapy-ready specialized treatment center.

scholarly journals Cranial shape diversification in horses: variation and covariation patterns under the impact of artificial selection

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Pauline Hanot ◽  
Jamsranjav Bayarsaikhan ◽  
Claude Guintard ◽  
Ashleigh Haruda ◽  
Enkhbayar Mijiddorj ◽  
...  
Keyword(s):  
Artificial Selection ◽  
Large Scale ◽  
Phenotypic Diversity ◽  
Morphological Changes ◽  
Rapid Evolution ◽  
Time Interval ◽  
Short Time Interval ◽  
Skull Morphology ◽  
Domestic Species ◽  
The Impact

AbstractThe potential of artificial selection to dramatically impact phenotypic diversity is well known. Large-scale morphological changes in domestic species, emerging over short timescales, offer an accelerated perspective on evolutionary processes. The domestic horse (Equus caballus) provides a striking example of rapid evolution, with major changes in morphology and size likely stemming from artificial selection. However, the microevolutionary mechanisms allowing to generate this variation in a short time interval remain little known. Here, we use 3D geometric morphometrics to quantify skull morphological diversity in the horse, and investigate modularity and integration patterns to understand how morphological associations contribute to cranial evolvability in this taxon. We find that changes in the magnitude of cranial integration contribute to the diversification of the skull morphology in horse breeds. Our results demonstrate that a conserved pattern of modularity does not constrain large-scale morphological variations in horses and that artificial selection has impacted mechanisms underlying phenotypic diversity to facilitate rapid shape changes. More broadly, this study demonstrates that studying microevolutionary processes in domestic species produces important insights into extant phenotypic diversity.

scholarly journals A Sigh of Relief: Vaccine-Associated Hypermetabolic Iymphadenopathy Following the Third Covid-19 Vaccine Dose is Short in Duration and Uncommonly Interferes with the Interpretation of [18F]FDG PET-CT Studies Performed in Oncologic Patients

2021 ◽  
Author(s):  
Dan Cohen ◽  
Shir Hazut Krauthammer ◽  
Ido Wolf ◽  
Einat Even-Sapir
Keyword(s):  
Fdg Pet ◽  
Vaccine Dose ◽  
Time Interval ◽  
Short Time Interval ◽  
The Third ◽  
Pet Ct ◽  
Oncologic Patients ◽  
Grade 3 ◽  
Fdg Pet Ct ◽  
The Impact

Abstract Purpose: The incidence of Covid-19 vaccine-associated hypermetabolic lymphadenopathy (VAHL) is high following the administration of the first and second BNT162b2 vaccine doses. The impact of this finding on [18F]FDG PET-CT interpretation and its correlation with the induced humoral immunity have been reported. Assuming the amnestic immune response is different following the third vaccine dose, we aimed to explore the incidence of VAHL over time after the third BNT162b2 dose administration, and its relevance to [18F]FDGPET-CT interpretation in oncologic patients.Methods: A total of 179 consecutive oncologic patients that underwent [18F]FDG PET-CT after a third BNT162b2 vaccine dose were included. The presence of VAHL was assessed. On VAHL-positive scans, the SUVmax, number, location and size of the“hot” nodes were recorded. The median time interval between vaccination and imagingwas 8 (IQR,5-14) days.Results: The incidences of all-grade VAHL and grade 3-4 VAHL were 47.5% and 8.9%,respectively. VAHL was identified on 82.5% of studies performed within the first 5 days from vaccination. Grade 3-4 VAHL was observed on 28.1% of studies performed within the first 5 days from vaccination, but was not detected on studies performed more than 5 days from vaccination. Separation between VAHL and malignant lymphadenopathy was not possible in only 2 of the 179 study patients. On a multivariable logistic regression, independent predictors of grade 3-4 VAHL were short time interval between vaccination and imaging (Pv<0.01), younger age (Pv<0.01) and lower BMI (Pv=0.03).Conclusion: VAHL is commonly identifiedon [18F]FDG PET-CT performed within the first 5 days from the third BNT162b2 vaccine doseadministration. High-grade VAHL is unlikely to be observed on a scan performed 6 days or longer from vaccination, and is even less likely in older and obese patients.

scholarly journals Assessment of the TROPOMI tropospheric NO<sub>2</sub> product based on airborne APEX observations

2020 ◽  
Author(s):  
Frederik Tack ◽  
Alexis Merlaud ◽  
Marian-Daniel Iordache ◽  
Gaia Pinardi ◽  
Ermioni Dimitropoulou ◽  
...  
Keyword(s):  
Remote Sensing ◽  
A Priori ◽  
Horizontal Distribution ◽  
Time Interval ◽  
Short Time Interval ◽  
Vertical Column ◽  
Data Set ◽  
Urban Regions ◽  
Tropospheric No2 ◽  
The Impact

Abstract. Sentinel-5 Precursor (S-5P), launched in October 2017, carrying the TROPOspheric Monitoring Instrument (TROPOMI) nadir-viewing spectrometer, is the first mission of the Copernicus Programme dedicated to the monitoring of air quality, climate, and ozone. In the presented study, the TROPOMI tropospheric nitrogen dioxide (NO2) L2 product (OFFL v1.03.01; 3.5 km × 7 km at nadir observations) has been validated over strongly polluted urban regions by comparison with coincident high-resolution Airborne Prism EXperiment (APEX) remote sensing observations (~75 m × 120 m). Satellite products can be optimally assessed based on (APEX) airborne remote sensing observations as a large amount of satellite pixels can be fully mapped at high accuracy and in a relatively short time interval, reducing the impact of spatio-temporal mismatches. In the framework of the S5PVAL-BE campaign, the APEX imaging spectrometer has been deployed during four mapping flights (26–29 June 2019) over the two largest urban regions in Belgium, i.e. Brussels and Antwerp, in order to map the horizontal distribution of tropospheric NO2. For each flight, 10 to 20 TROPOMI pixels were fully covered by approximately 2800 to 4000 APEX measurements within each TROPOMI pixel. The TROPOMI and APEX NO2 vertical column density (VCD) retrieval schemes are similar in concept. Overall for the ensemble of the four flights, the standard TROPOMI NO2 VCD product is well correlated (R = 0.92) but biased negatively by −1.2 ± 1.2 × 1015 molec cm−2 or −14 % ± 12 %, on average, with respect to coincident APEX NO2 retrievals. When replacing the coarse 1° × 1° TM5-MP a priori NO2 profiles by NO2 profile shapes from the CAMS regional CTM ensemble at 0.1° × 0.1°, the slope increases by 11 % to 0.93, and the bias is reduced to −0.1 ± 1.0 × 1015 molec cm−2 or −1.0 % ± 12 %. When the absolute value of the difference is taken, the bias is 1.3 × 1015 molec cm−2 or 16 %, and 0.7 × 1015 molec cm−2 or 9 % on average, when comparing APEX NO2 VCDs with TM5-MP-based and CAMS-based NO2 VCDs, respectively. Both sets of retrievals are well within the accuracy requirement of a maximum bias of 25–50 % for the TROPOMI tropospheric NO2 product for all individual compared pixels. Additionally, the APEX data set allows the study of TROPOMI subpixel variability and impact of signal smoothing due to its finite satellite pixel size, typically coarser than fine-scale gradients in the urban NO2 field. The amount of underestimation of peak plume values and overestimation of urban background values in the TROPOMI data is in the order of 1–2 × 1015 molec cm−2 on average, or 10 %–20 %, in case of an urban scene.

Simulation of Droplet Flows Using Lattice Boltzmann Method

2008 ◽  
Author(s):  
Amit Gupta ◽  
Ranganathan Kumar
Keyword(s):  
Surface Tension ◽  
Lattice Boltzmann Method ◽  
Lattice Boltzmann ◽  
Potential Method ◽  
Time Interval ◽  
Short Time Interval ◽  
Impact Surface ◽  
Spread Factor ◽  
Boltzmann Method ◽  
The Impact

In this work, the mesoscale approach of two-dimensional lattice Boltzmann method (LBM) has been employed to study droplet collision with a dry wall. The impact of drops with solid walls is simulated by using the pseudo-potential method of LBM. Simulations have been conducted for 2<We<162, and it is shown that the maximum spreading of the drop on the solid surface depends on the surrounding density, velocity of impact, surface tension, and the surface wetting characteristics. For a short time interval right after the impact the spreading diameter is shown to follow a parabolic dependence with time. The spread factor is seen to be higher as the Weber number increases. Under certain conditions when the drop has a high impact velocity and/or low surface tension, the kinetic energy of impact dominates over the dissipation and surface energy, leading to breakup of the drop into smaller drops. This breakup is shown to depend upon the wetting/non-wetting nature of the surface used. The spread factor is found to be a maximum at the time of breakup.

Assessment of the S-5P tropospheric NO2 product based on coincident airborne APEX observations over polluted regions

2020 ◽  
Author(s):  
Frederik Tack ◽  
Alexis Merlaud ◽  
Marian-Daniel Iordache ◽  
Gaia Pinardi ◽  
Ermioni Dimitropoulou ◽  
...  
Keyword(s):  
High Resolution ◽  
A Priori ◽  
Horizontal Distribution ◽  
Time Interval ◽  
Short Time Interval ◽  
Vertical Column ◽  
Urban Regions ◽  
Accuracy Requirement ◽  
Spatio Temporal ◽  
The Impact

&lt;p&gt;Sentinel-5 Precursor (S-5P), launched in October 2017, is the first mission of the Copernicus Programme dedicated to the monitoring of air quality and climate. Its characteristics, such as the fine spatial resolution, introduce many new opportunities and challenges, requiring to carefully assess the quality and validity of the generated data products by comparison with independent reference observations.&lt;/p&gt;&lt;p&gt;In the presented study, the S-5P/TROPOMI tropospheric nitrogen dioxide (NO&lt;sub&gt;2&lt;/sub&gt;) L2 product (3.5 x 7 km&lt;sup&gt;2 &lt;/sup&gt;at nadir observations) has been validated over strongly polluted urban regions based on comparison with coincident high-resolution airborne remote sensing observations (~100 m&lt;sup&gt;2&lt;/sup&gt;). Airborne imagers are able to map the horizontal distribution of tropospheric NO&lt;sub&gt;2&lt;/sub&gt;, as well as its strong spatio-temporal variability, at high resolution and with high accuracy. Satellite products can be optimally assessed based on airborne observations as a large amount of satellite pixels can be fully mapped in a relatively short time interval, reducing the impact of spatiotemporal mismatches. Additionally, such data sets allow to study the TROPOMI subpixel variability and impact of signal smoothing due to its finite satellite pixel size, typically coarser than fine-scale gradients in the urban NO&lt;sub&gt;2&lt;/sub&gt; field.&lt;/p&gt;&lt;p&gt;In the framework of the S5PVAL-BE campaign, the Airborne Prism EXperiment (APEX) imaging spectrometer has been deployed during four mapping flights (26-29 June 2019) over the two largest urban regions in Belgium, i.e. Brussels and Antwerp, in order to map the horizontal distribution of tropospheric NO&lt;sub&gt;2&lt;/sub&gt;. Per flight, 15 to 20 TROPOMI pixels were fully covered by approximately 5000 APEX measurements for each TROPOMI pixel. Mapping flights and ancillary ground-based measurements (car-mobile DOAS, MAX-DOAS, CIMEL, ceilometer, etc.) were conducted in coincidence with the overpass of TROPOMI (typically between noon and 2 PM UTC). The TROPOMI and APEX NO&lt;sub&gt;2&lt;/sub&gt; vertical column density (VCD) retrieval schemes are similar in concept. Retrieved NO&lt;sub&gt;2 &lt;/sub&gt;VCDs were georeferenced, gridded and intercompared. As strongly polluted areas typically exhibit strong NO&lt;sub&gt;2 &lt;/sub&gt;vertical gradients (besides the strong horizontal gradients), a custom TROPOMI tropospheric NO&lt;sub&gt;2 &lt;/sub&gt;product was computed and compared as well with APEX by replacing the coarse 1&amp;#176; x 1&amp;#176; a priori NO&lt;sub&gt;2 &lt;/sub&gt;vertical profiles from TM5-MP by NO&lt;sub&gt;2&lt;/sub&gt; profile shapes from the CAMS regional CTM ensemble at 0.1&amp;#176; x 0.1&amp;#176;.&lt;/p&gt;&lt;p&gt;Overall for the ensemble of the four flights, the standard TROPOMI NO&lt;sub&gt;2&lt;/sub&gt; VCD product is well correlated (R= 0.94) but biased low (slope = 0.73) with respect to APEX NO&lt;sub&gt;2&lt;/sub&gt; retrievals. When replacing the TM5-MP a priori NO&lt;sub&gt;2&lt;/sub&gt; profiles by CAMS-based profiles, the slope increases to 0.88. When calculating the NO&lt;sub&gt;2&lt;/sub&gt; VCD differences, the bias is on average -1.3 &amp;#177; 1.2 x 10&lt;sup&gt;15&lt;/sup&gt; molec cm&lt;sup&gt;-2&lt;/sup&gt; or -16% &amp;#177; 11% for the difference between APEX NO&lt;sub&gt;2&lt;/sub&gt; VCDs and the standard TROPOMI NO&lt;sub&gt;2&lt;/sub&gt; VCD product. The bias is substantially reduced when replacing the coarse TM5-MP a priori NO&lt;sub&gt;2&lt;/sub&gt; profiles by CAMS-based profiles, being -0.1 &amp;#177; 1.1&amp;#160; x 10&lt;sup&gt;15&lt;/sup&gt; molec cm&lt;sup&gt;-2&lt;/sup&gt; or -0.1% &amp;#177; 11%. Both sets of retrievals are well within the accuracy requirement of a maximum bias of 25-50% for the TROPOMI tropospheric NO&lt;sub&gt;2&lt;/sub&gt; product for all individual compared pixels.&lt;/p&gt;

scholarly journals Features of radial growth dynamics of english oak in the conditions of radioactive contamination of forests of Central forest steppe

10.12737/6277 ◽  
2014 ◽  
Vol 4 (3) ◽  
pp. 130-139
Author(s):  
Щетинкин ◽  
Sergey Shchetinkin ◽  
Щетинкина ◽  
Natalya Shchetinkina
Keyword(s):  
Woody Plants ◽  
Growth Dynamics ◽  
Oak Forests ◽  
Forest Steppe ◽  
Time Interval ◽  
Short Time Interval ◽  
Lateral Meristem ◽  
English Oak ◽  
Short Time ◽  
The Impact

It is shown that the overall thrusts of processes of xylogeneses of oak in conditions of radioac-tive contamination are consistent with pre-viously established researchers for oak forests of Central forest steppe. Irradiation, mostly with short-lived isotopes of iodine, caused changes in the activity of the lateral meristem of woody plants - cambium. The impact had relatively short time interval and affected mainly xylogeneses of early wood regardless of the age of forming layer of wood.

scholarly journals FEM Analysis of Textile Reinforced Composite Materials Impact Behavior

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7380
Author(s):  
Savin Dorin Ionesi ◽  
Luminita Ciobanu ◽  
Catalin Dumitras ◽  
Manuela Avadanei ◽  
Ionut Dulgheriu ◽  
...  
Keyword(s):  
Composite Materials ◽  
Impact Resistance ◽  
Fem Analysis ◽  
Impact Behavior ◽  
Time Interval ◽  
Short Time Interval ◽  
Element Analysis ◽  
Textile Reinforced Composite ◽  
And Behavior ◽  
The Impact

Composite materials reinforced with textile fabrics represent a complex subject. When explaining these materials, one must consider their mechanical behavior in general, and impact resistance in particular, as many applications are characterized by dynamic strains. Impact characteristics must be considered from the early stages of the design process in order to be controlled through structure, layer deposition and direction. Reinforcement materials are essential for the quality and behavior of composites, and textile reinforcements present a large range of advantages. It takes a good understanding of the requirements specific to an application to accurately design textile reinforcements. Currently, simulations of textile reinforcements and composites are efficient tools to forecast their behavior during both processing and use. The paper presents the steps that must be followed for modelling the impact behavior of composite materials, using finite element analysis (FEM). The FEM model built using Deform 3D software offers information concerning the behavior structure during impact. The behavior can be visualized for the structure as a whole and, for different sections, be considered significant. Furthermore, the structure’s strain can be visualized at any moment. In real impact tests, this is not possible due to the very short time interval and the impossibility to record inside the structure, as well as to record all significant stages using conventional means.

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