A simple analysis of the effects of large magnitude acceleration pulses on diffusion-mediated processes

2000 ◽  
Author(s):  
Charles Panzarella ◽  
Arnon Chait
1989 ◽  
Vol 156 (1) ◽  
pp. 243-251 ◽  
Author(s):  
M. Tomášek ◽  
Š. Pick ◽  
G. V. Gadiyak ◽  
Yu. N. Morokov

2020 ◽  
pp. 204141962098448
Author(s):  
Hezi Y Grisaro ◽  
Michael V Seica ◽  
Jeffrey A Packer ◽  
Wei Li

The analysis of structural members subjected to close-in detonations involves a complicated dynamic scenario. Since the charge is very close to the structural member, the reflected pressure distribution on the member surface is highly non-uniform. In addition, the level of damage to the structural member may be high because of the large magnitude of the load. Due to these phenomena, the response of a structural member to close-in detonation cannot be accurately modelled by relatively simple methods like single-degree of freedom models, and more complicated models are required. Such models need to include numerical simulation of the detonation process, which produces a non-uniform pressure environment, allowing the pressure to reflect and flow around the member section. The local damage and flow around the section are especially of interest in I-shaped, or wide-flange-section members. Herein, the response of such sections is modelled by numerical simulations using a novel technique, which overcomes the difficulty of computation time, and is validated through various calculations. The model is used to perform a parametric study to investigate the response of I-sections subjected to close-in detonations, in terms of local damage and global behaviour, with scaled distances of 0.15–0.29 m/kg1/3 and loading causing flexure about the strong axis. Various aspects that affect the performance are studied, such as: the effect of scaled distance, the addition of welded stiffening plates between the flanges and web, the effect of boundary conditions and the effect of charge shape. Resulting local damage and residual deformations are assessed for the cases studied.


Author(s):  
Michele Pellegrino ◽  
Mario Pinto ◽  
Fabio Marson ◽  
Stefano Lasaponara ◽  
Fabrizio Doricchi

AbstractIt is debated whether the representation of numbers is endowed with a directional-spatial component so that perceiving small-magnitude numbers triggers leftward shifts of attention and perceiving large-magnitude numbers rightward shifts. Contrary to initial findings, recent investigations have demonstrated that centrally presented small-magnitude and large-magnitude Arabic numbers do not cause leftward and rightward shifts of attention, respectively. Here we verified whether perceiving small or large non-symbolic numerosities (i.e., clouds of dots) drives attention to the left or the right side of space, respectively. In experiment 1, participants were presented with central small (1, 2) vs large-numerosity (8, 9) clouds of dots followed by an imperative target in the left or right side of space. In experiment 2, a central cloud of dots (i.e., five dots) was followed by the simultaneous presentation of two identical dot-clouds, one on the left and one on the right side of space. Lateral clouds were both lower (1, 2) or higher in numerosity (8, 9) than the central cloud. After a variable delay, one of the two lateral clouds turned red and participants had to signal the colour change through a unimanual response. We found that (a) in Experiment 1, the small vs large numerosity of the central cloud of dots did not speed up the detection of left vs right targets, respectively, (b) in Experiment 2, the detection of colour change was not faster in the left side of space when lateral clouds were smaller in numerosity than the central reference and in the right side when clouds were larger in numerosity. These findings show that perceiving non-symbolic numerosity does not cause automatic shifts of spatial attention and suggests no inherent association between the representation of numerosity and that of directional space.


2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
M. Chiesa ◽  
F. Maltoni ◽  
L. Mantani ◽  
B. Mele ◽  
F. Piccinini ◽  
...  

Abstract Measuring the shape of the Higgs boson potential is of paramount importance, and will be a challenging task at current as well as future colliders. While the expectations for the measurement of the trilinear Higgs self-coupling are rather promising, an accurate measurement of the quartic self-coupling interaction is presently considered extremely challenging even at a future 100 TeV proton-proton collider. In this work we explore the sensitivity that a muon collider with a center of mass energy in the multi-TeV range and luminosities of the order of 1035cm−2s−1, as presently under discussion, might provide, thanks to a rather large three Higgs-boson production and to a limited background. By performing a first and simple analysis, we find a clear indication that a muon collider could provide a determination of the quartic Higgs self-coupling that is significantly better than what is currently considered attainable at other future colliders.


2021 ◽  
Vol 69 (2) ◽  
Author(s):  
Jiaxin Ye ◽  
Jiazhou Xuan ◽  
Yongliang Qiao ◽  
Yifan Zhang ◽  
Haiyang Zhang ◽  
...  

2021 ◽  
pp. 106002802199964
Author(s):  
Matthew D. Jones ◽  
Jonathan Clarke ◽  
Calandra Feather ◽  
Bryony Dean Franklin ◽  
Ruchi Sinha ◽  
...  

Background: In a recent human reliability analysis (HRA) of simulated pediatric resuscitations, ineffective retrieval of preparation and administration instructions from online injectable medicines guidelines was a key factor contributing to medication administration errors (MAEs). Objective: The aim of the present study was to use a specific HRA to understand where intravenous medicines guidelines are vulnerable to misinterpretation, focusing on deviations from expected practice ( discrepancies) that contributed to large-magnitude and/or clinically significant MAEs. Methods: Video recordings from the original study were reanalyzed to identify discrepancies in the steps required to find and extract information from the NHS Injectable Medicines Guide (IMG) website. These data were combined with MAE data from the same original study. Results: In total, 44 discrepancies during use of the IMG were observed across 180 medication administrations. Of these discrepancies, 21 (48%) were associated with an MAE, 16 of which (36% of 44 discrepancies) made a major contribution to that error. There were more discrepancies (31 in total, 70%) during the steps required to access the correct drug webpage than there were in the steps required to read this information (13 in total, 30%). Discrepancies when using injectable medicines guidelines made a major contribution to 6 (27%) of 22 clinically significant and 4 (15%) of 27 large-magnitude MAEs. Conclusion and Relevance: Discrepancies during the use of an online injectable medicines guideline were often associated with subsequent MAEs, including those with potentially significant consequences. This highlights the need to test the usability of guidelines before clinical use.


2021 ◽  
Vol 7 (13) ◽  
pp. eaaz5691
Author(s):  
Kimberly Blisniuk ◽  
Katherine Scharer ◽  
Warren D. Sharp ◽  
Roland Burgmann ◽  
Colin Amos ◽  
...  

The San Andreas fault has the highest calculated time-dependent probability for large-magnitude earthquakes in southern California. However, where the fault is multistranded east of the Los Angeles metropolitan area, it has been uncertain which strand has the fastest slip rate and, therefore, which has the highest probability of a destructive earthquake. Reconstruction of offset Pleistocene-Holocene landforms dated using the uranium-thorium soil carbonate and beryllium-10 surface exposure techniques indicates slip rates of 24.1 ± 3 millimeter per year for the San Andreas fault, with 21.6 ± 2 and 2.5 ± 1 millimeters per year for the Mission Creek and Banning strands, respectively. These data establish the Mission Creek strand as the primary fault bounding the Pacific and North American plates at this latitude and imply that 6 to 9 meters of elastic strain has accumulated along the fault since the most recent surface-rupturing earthquake, highlighting the potential for large earthquakes along this strand.


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