An integral insight into pollen wall development: involvement of physical processes in exine ontogeny in Calycanthus floridus L., with an experimental approach

2020 ◽  
Author(s):  
Nina I. Gabarayeva ◽  
Valentina V. Grigorjeva
Keyword(s):  
Experimental Approach ◽  
Pollen Wall ◽  
Physical Processes ◽  
Insight Into

scholarly journals Effects of rotational submarine slump dynamics on tsunami genesis: new insight from idealized models and the 1929 Grand Banks event

2020 ◽  
Vol 500 (1) ◽  
pp. 41-61 ◽  
Author(s):  
T. Zengaffinen ◽  
F. Løvholt ◽  
G. K. Pedersen ◽  
C. B. Harbitz
Keyword(s):  
Source Information ◽  
Physical Processes ◽  
Viscoplastic Model ◽  
Grand Banks ◽  
Rotational Kinematics ◽  
Short Run ◽  
Submarine Slump ◽  
Geological Source ◽  
Insight Into

AbstractSediment slumps are known to have generated important tsunamis such as the 1998 Papua New Guinea (PNG) and the 1929 Grand Banks events. Tsunami modellers commonly use solid blocks with short run-out distances to simulate these slumps. While such methods have the obvious advantage of being simple to use, they offer little or no insight into physical processes that drive the events. The importance of rotational slump motion to tsunamigenic potential is demonstrated in this study by employing a viscoplastic landslide model with Herschel–Bulkley rheology. A large number of simulations for different material properties and landslide configurations are carried out to link the slump's deformation, rheology, its translational and rotational kinematics, to its tsunami genesis. The yield strength of the slump is shown to be the primary material property that determines the tsunami genesis. This viscoplastic model is further employed to simulate the 1929 Grand Banks tsunami using updated geological source information. The results of this case study suggest that the viscoplastic model can be used to simulate complex slump-induced tsunami. The simulations of the 1929 Grand Banks event also indicate that a pure slump mechanism is more tsunamigenic than a corresponding translational landslide mechanism.

scholarly journals Insight into the self-assembly of water-soluble perylene bisimide derivatives through a combined computational and experimental approach

Nanoscale ◽  
2019 ◽  
Vol 11 (34) ◽  
pp. 15917-15928 ◽  
Author(s):  
Emily R. Draper ◽  
Liam Wilbraham ◽  
Dave J. Adams ◽  
Matthew Wallace ◽  
Ralf Schweins ◽  
...  
Keyword(s):  
Amino Acid ◽  
Self Assembly ◽  
Experimental Approach ◽  
Water Soluble ◽  
The Self ◽  
Experimental Techniques ◽  
Perylene Bisimide ◽  
Perylene Bisimides ◽  
Insight Into

We use a combination of computational and experimental techniques to study the self-assembly and gelation of amino-acid functionalised water-soluble perylene bisimides.

scholarly journals Enabling cutting-edge semiconductor simulation through grid technology

2009 ◽  
Vol 367 (1897) ◽  
pp. 2573-2584 ◽  
Author(s):  
Dave Reid ◽  
Campbell Millar ◽  
Scott Roy ◽  
Gareth Roy ◽  
Richard Sinnott ◽  
...  
Keyword(s):  
Semiconductor Industry ◽  
Complementary Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Detailed Knowledge ◽  
Grid Technology ◽  
Physical Processes ◽  
Statistical Variations ◽  
Scientific Results ◽  
The Many ◽  
Insight Into

The progressive scaling of complementary metal oxide semiconductor (CMOS) transistors drives the success of the global semiconductor industry. Detailed knowledge of transistor behaviour is necessary to overcome the many fundamental challenges faced by chip and systems designers. Grid technology has enabled the unavoidable statistical variations introduced by scaling to be examined in unprecedented detail. Over 200 000 transistors have been simulated, the results of which provide detailed insight into underlying physical processes. This paper outlines recent scientific results of the nanoCMOS project and describes the way in which the scientific goals have been reflected in the grid-based e-Infrastructure.

scholarly journals On High Frequency Polar Motion and Length of Day Variations

2000 ◽  
Vol 178 ◽  
pp. 545-554
Author(s):  
K. Arfa-Kaboodvand ◽  
E. Groten
Keyword(s):  
Frequency Spectrum ◽  
Earth Rotation ◽  
High Frequency ◽  
Polar Motion ◽  
Length Of Day ◽  
Physical Processes ◽  
Earth Orientation ◽  
Tidal Forces ◽  
Diurnal Range ◽  
Insight Into

AbstractThe 0.042-day Earth rotation data (diurnal and semidiurnal) computed by the International GPS Service were used to analyze the daily/sub-daily variations of polar motion (PM) and length of day (LOD). Systematic and advanced spectral analytical investigations of the degree of periodic variability have been carried out. They show that the prominent periodical components can be found at the tidal frequencies of zonal, tesseral and sectorial waves. These investigations should give better insight into the physical processes, which influence Earth orientation (i.e. due to the atmospheric and oceanic motions, tidal forces etc.). It should be the basis for the detailed modeling of excitation functions in the sub-diurnal range of the high-frequency spectrum.

THE SYNTHESIS OF SEISMOGRAMS FROM WELL LOG DATA

Geophysics ◽  
1955 ◽  
Vol 20 (3) ◽  
pp. 516-538 ◽  
Author(s):  
R. A. Peterson ◽  
W. R. Fillippone ◽  
F. B. Coker
Keyword(s):  
Analogue Computer ◽  
Physical Processes ◽  
Physical Conditions ◽  
Interesting Insight ◽  
Close Relationship ◽  
Seismic Records ◽  
Set Up ◽  
Well Data ◽  
Seismic Reflections ◽  
Insight Into

Under certain simplified but realistic physical assumptions, the basic data from continuous velocity surveys in wells can be used to simulate the variations in acoustic impedance in the ground which give rise to seismic reflections. An analogue computer is described which makes use of the basic well data to produce synthetic seismic records which resemble actual seismograms from shothole explosions. This process provides an interesting insight into the requisite physical conditions, as well as the physical processes, whereby seismic reflections are set up in the earth. The close relationship between seismograms and well logs is brought out. Illustrations are given of field results.

Airflow-Housing-Induced Resonances of Rotating Optical Disks

2007 ◽  
Vol 74 (6) ◽  
pp. 1252-1263 ◽  
Author(s):  
R. M. C. Mestrom ◽  
R. H. B. Fey ◽  
H. Nijmeijer ◽  
P. M. R. Wortelboer ◽  
W. Aerts
Keyword(s):  
Numerical Model ◽  
Pressure Distribution ◽  
Critical Speed ◽  
Experimental Approach ◽  
Experimental Results ◽  
Lubrication Equation ◽  
Global View ◽  
Optical Disks ◽  
Insight Into ◽  
Finite Difference Techniques

Numerous excitation sources for disk vibrations are present in optical drives. For increasing rotation speeds, airflow-housing-induced vibrations have become more and more important. Currently, drives are designed in which rotation speeds are so high that critical speed resonances may show up. The presence of these resonances depends on the layout of the inner housing geometry of the drive. The influence of the drive inner housing geometry is investigated systematically by means of a numerical-experimental approach. An analytical model is derived, containing disk dynamics and the geometry-induced pressure distribution acting as the excitation mechanism on the disk. The Reynolds’ lubrication equation is used as a first approach for the modeling of the pressure distribution. The model is numerically implemented using an approach based on a combination of finite element and finite difference techniques. An idealized, drive-like environment serves as the experimental setup. This setup resembles the situation in the numerical model, in order to be able to verify the numerical model. Wedge-like airflow disturbances are used in order to obtain insight into the influence of drive inner geometry on the critical speed resonances of optical disks. A disk tilt measurement method is designed that yields a global view of the disk deformation. By means of two newly proposed types of plots, numerical and experimental results can be compared in a straightforward way. A qualitative match between the numerical and experimental results is obtained. The numerical and experimental methods presented provide insight into airflow-housing-induced vibrations in optical drives. Additionally, reduction of some critical speed resonances is found to be possible for certain drive inner geometry configurations.

scholarly journals Efficient dissemination of prions through preferential transmission to nearby cells

2007 ◽  
Vol 88 (2) ◽  
pp. 706-713 ◽  
Author(s):  
Sophie Paquet ◽  
Christelle Langevin ◽  
Jérome Chapuis ◽  
Graham S. Jackson ◽  
Hubert Laude ◽  
...  
Keyword(s):  
Experimental Approach ◽  
Critical Issue ◽  
Target Cells ◽  
Cell Analysis ◽  
Infectious Agents ◽  
Donor Cells ◽  
Infected Cells ◽  
Range Spread ◽  
Cell Spread ◽  
Insight Into

Despite circumstantial evidence that prions can be found extracellularly or at the surface of infected cells, little is known about how these infectious agents spread from cell to cell. In order to gain better insight into this critical issue, this study used two different cell lines (neuroglial MovS and epithelial Rov cells) that have previously been shown to be permissive for ovine prion multiplication. Co-culture of infected cells and uninfected target cells at a ratio of 1 : 9 resulted in total infection of MovS cells within 10 days but not of Rov cell cultures, suggesting that the efficiency of prion dissemination may vary greatly depending on the type of permissive cell. Analysis of the spatial distribution of the newly infected cells revealed that, although long-range spread could also occur, cells proximal to the infected donor cells consistently accumulated more abnormal PrP, consistent with preferential infection of nearby cells. This experimental approach, focused on dissemination among living cells, could help in the analysis of mechanisms involved in the cell-to-cell spread of prion infections.

scholarly journals HST Observations of the Toomre Sequence of Merging Galaxies

2004 ◽  
Vol 217 ◽  
pp. 432-433
Author(s):  
Jörn Rossa ◽  
Roeland P. Van Der Marel ◽  
Torsten Böker ◽  
Seppo Laine ◽  
J. Christopher Mihos ◽  
...  
Keyword(s):  
Stellar Populations ◽  
Nuclear Morphology ◽  
Physical Processes ◽  
Galaxy Interactions ◽  
Merging Galaxies ◽  
Nuclear Regions ◽  
Insight Into

We discuss our ongoing multi-instrument HST investigation of the nuclear regions of the 11 interacting and merging galaxies in the Toomre Sequence. We are studying the nuclear kinematics using STIS (G750M) spectra, the nuclear stellar populations using STIS (G430L) spectra, and the nuclear morphology using NICMOS and WFPC2 images. The results will provide new insight into the physical processes that operate during galaxy interactions.

On the Attempt to Implement Social Addressability within a Robotic System

i-com ◽  
2017 ◽  
Vol 16 (2) ◽  
pp. 71-85
Author(s):  
Philipp Graf ◽  
Manuela Marquardt ◽  
Diego Compagna
Keyword(s):  
Experimental Approach ◽  
Human Robot Interaction ◽  
Light Conditions ◽  
Robot System ◽  
Robot Interaction ◽  
Additional Information ◽  
The Status ◽  
User Friendly ◽  
To Receive ◽  
Insight Into

AbstractWe conducted a Human-Robot Interaction (HRI) study during a science event, using a mixed method experimental approach with quantitative and qualitative data (adapted version of Godspeed Questionnaire and audio-visual material analysed videographically). The main purpose of the research was to gather insight into the relevance of the so-called “point of interaction” for a successful and user-friendly interaction with a non-anthropomorphic robot. We elaborate on this concept with reference to sociological theories under the heading of “addressability” and “social address” and generate hypotheses informed by former research and theoretical reflections. We implement an interface on our robot system, comprising two LEDs, which indicate the status of the robot/interaction, and which might possibly serve as basal form of embodied social address. In one experimental condition, the movements were accompanied by a light choreography, the other one was conducted without the LEDs. Our findings suggest a potential relevance of social address for the interaction partner to receive additional information, especially if the situation is a contingent one. Nevertheless, the overall rating on the Godspeed scales showed no significant differences between the light conditions. Several possible reasons for this are discussed. Limitations and advantages are pointed out in the conclusion.

scholarly journals Innovative solutions in transformer theory

2021 ◽  
pp. 5-31
Author(s):  
Mansur A. Shakyrov ◽  
◽  
Anton A. Tkachuk ◽  
Keyword(s):  
Energy Transfer ◽  
Magnetic Permeability ◽  
Analytical Modeling ◽  
Poynting Vector ◽  
Practical Importance ◽  
Standard Theory ◽  
Physical Processes ◽  
Innovative Solutions ◽  
Mathematical Equations ◽  
Insight Into

Objective: Clarification of the reasons for errors in the traditional transformer theory and ways of correcting it based on more accurate physical and mathematical equations for describing the pro- cesses of energy transfer in a transformer using the Poynting vector. Demonstrating a new principle of operation and the resulting new properties of the transformer. Methods: The study applies transi- tion from analytical modeling of the device behavior to its equivalent circuit displaying the magnetic fluxes of the transformer. The specific feature of this approach is that at first it is applied to an ideali- zed transformer with infinite magnetic permeability of steel, after which the circuit is built up with elements that take into account saturation and losses in the steel of a real device. Results: The con- tradictions and paradoxes of the standard theory have been revealed. The findings have shown the need to replace it with a doctrine based on equations for real, measurable magnetic fluxes instead of virtual (contrived) fluxes of the official theory. The correctness and significance of the proposed theo- ry is confirmed by the discovery of new properties of transformers and the capability of using it to explain the magnetic overexcitation of individual sections of the transformer in emergency modes. Practical importance: Conditions are provided, and ways are outlined for creating correct textbooks instead of standard ones with outdated ideas about physical processes in transformers. A deeper insight into the operation of transformers resulting from the new theory should contribute to the improvement of methods for increasing their electrodynamic withstand

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