In Situ Self‐Organizing Materials for Local Stress‐Responsive Reconstruction of Skin Interstitium

2021 ◽  
pp. 2100119
Author(s):  
Xinxiao Han ◽  
Wenda Hua ◽  
Yuqi Liu ◽  
Zhuo Ao ◽  
Dong Han
Keyword(s):  
Local Stress ◽  
Self Organizing

scholarly journals A Surface Integral Method for Determining Ice Loads on Offshore Structures from In Situ Measurements

1983 ◽  
Vol 4 ◽  
pp. 124-128 ◽  
Author(s):  
Jerome B. Johnson
Keyword(s):  
Mathematical Model ◽  
Integral Method ◽  
Local Stress ◽  
Offshore Structures ◽  
Surface Integral ◽  
Stress Measurements ◽  
Ice Loads ◽  
Ice Failure ◽  
Stress Variations

Two methods are presented for calculating ice loads on structures using measurements from sensors imbedded in a floating ice sheet and from instruments attached to a structure. The first method uses a mathematical model describing ice/structure interaction for a cylindrical structure to interpret stress measurements. This technique requires only a few sensors to develop an estimate of ice loads, However, analytical and experimental results indicate that using a mathematical model to interpret stress measurements can result in inaccurate load estimates due to uncertainty in the accuracy of the model and and the uncertainty of using local ice stresses to calculate total ice forces. The second method of calculating ice loads on structures utilizes Euler and Cauchy’s stress principle. In this, the surface integral method, the force acting on a structure is determined by summing the stress vectors acting on a surface which encompasses the structure. Application of this technique requires that the shear and normal components of stress be known along the surface. Sensors must be spaced close enough together so that local stress variations due to the process of ice failure around a structure can be detected. The surface integral method is a useful technique for interpreting load and stress measurements since a knowledge of the mechanism of ice/structure interactions is not needed. The accuracy of the method is determined by the density of sensors along the surface. A disadvantage of the technique is that a relatively large number of sensors are needed to determine the stress tensor along the surface of interest.The surface integral method can be used to examine the effects of grounded ice rubble on structural ice loads. Two instrumented surfaces, one enclosing a structure and the other enclosing the structure and rubble field can be used to estimate the load acting only on the structure and also on the structure/ rubble-field system.

scholarly journals Variations in the summer oceanic <i>p</i>CO<sub>2</sub> and carbon sink in Prydz Bay using the self-organizing map analysis approach

2019 ◽  
Vol 16 (3) ◽  
pp. 797-810 ◽  
Author(s):  
Suqing Xu ◽  
Keyhong Park ◽  
Yanmin Wang ◽  
Liqi Chen ◽  
Di Qi ◽  
...  
Keyword(s):  
Sea Ice ◽  
Open Ocean ◽  
Sea Surface ◽  
Prydz Bay ◽  
Self Organizing Map ◽  
Ocean Region ◽  
Co2 Sink ◽  
Shelf Region ◽  
Self Organizing

Abstract. This study applies a neural network technique to produce maps of oceanic surface pCO2 in Prydz Bay in the Southern Ocean on a weekly 0.1∘ longitude × 0.1∘ latitude grid based on in situ measurements obtained during the 31st CHINARE cruise from February to early March 2015. This study area was divided into three regions, namely, the “open-ocean” region, “sea-ice” region and “shelf” region. The distribution of oceanic pCO2 was mainly affected by physical processes in the open-ocean region, where mixing and upwelling were the main controls. In the sea-ice region, oceanic pCO2 changed sharply due to the strong change in seasonal ice. In the shelf region, biological factors were the main control. The weekly oceanic pCO2 was estimated using a self-organizing map (SOM) with four proxy parameters (sea surface temperature, chlorophyll a concentration, mixed Layer Depth and sea surface salinity) to overcome the complex relationship between the biogeochemical and physical conditions in the Prydz Bay region. The reconstructed oceanic pCO2 data coincide well with the in situ pCO2 data from SOCAT, with a root mean square error of 22.14 µatm. Prydz Bay was mainly a strong CO2 sink in February 2015, with a monthly averaged uptake of 23.57±6.36 TgC. The oceanic CO2 sink is pronounced in the shelf region due to its low oceanic pCO2 values and peak biological production.

Geo-Stress Direction Evaluation Method Based on Numerical Simulation

2014 ◽  
Vol 580-583 ◽  
pp. 2011-2014
Author(s):  
Su Chao Xu ◽  
C Y. Jin
Keyword(s):  
Numerical Simulation ◽  
Evaluation Method ◽  
Maximum Shear Stress ◽  
Local Stress ◽  
Surrounding Rock ◽  
Hydropower Station ◽  
Local Stress Concentration ◽  
Stress Direction ◽  
Baihetan Hydropower Station

The phenomenon of spalling at Baihetan Hydropower Station is influenced by such factors as the stress redistribution in surrounding rock, the local stress concentration and also poor properties of disturbed belt. In this paper, a series of numerical simulation were carried out and some beneficial conclusions were gained as follows: 1) the ratio of maximum shear stress and uniaxial compressive strength is more rational in the prediction of spalling and can give confident explanation for “V” shape pits; 2) the in-situ geo-stress direction is in accordance with NNE and NE.

scholarly journals Remote sensing the sea surface CO<sub>2</sub> of the Baltic Sea using the SOMLO methodology

2015 ◽  
Vol 12 (11) ◽  
pp. 3369-3384 ◽  
Author(s):  
G. Parard ◽  
A. A. Charantonis ◽  
A. Rutgerson
Keyword(s):  
Baltic Sea ◽  
High Variability ◽  
In Situ Measurements ◽  
Sea Surface ◽  
Accurate Estimation ◽  
The Baltic Sea ◽  
Validation Data ◽  
The Baltic ◽  
Self Organizing

Abstract. Studies of coastal seas in Europe have noted the high variability of the CO2 system. This high variability, generated by the complex mechanisms driving the CO2 fluxes, complicates the accurate estimation of these mechanisms. This is particularly pronounced in the Baltic Sea, where the mechanisms driving the fluxes have not been characterized in as much detail as in the open oceans. In addition, the joint availability of in situ measurements of CO2 and of sea-surface satellite data is limited in the area. In this paper, we used the SOMLO (self-organizing multiple linear output; Sasse et al., 2013) methodology, which combines two existing methods (i.e. self-organizing maps and multiple linear regression) to estimate the ocean surface partial pressure of CO2 (pCO2) in the Baltic Sea from the remotely sensed sea surface temperature, chlorophyll, coloured dissolved organic matter, net primary production, and mixed-layer depth. The outputs of this research have a horizontal resolution of 4 km and cover the 1998–2011 period. These outputs give a monthly map of the Baltic Sea at a very fine spatial resolution. The reconstructed pCO2 values over the validation data set have a correlation of 0.93 with the in situ measurements and a root mean square error of 36 μatm. Removing any of the satellite parameters degraded this reconstructed CO2 flux, so we chose to supply any missing data using statistical imputation. The pCO2 maps produced using this method also provide a confidence level of the reconstruction at each grid point. The results obtained are encouraging given the sparsity of available data, and we expect to be able to produce even more accurate reconstructions in coming years, given the predicted acquisition of new data.

Direct Local Strain Measurement In Damascene Interconnects

2007 ◽  
Vol 990 ◽  
Author(s):  
Moustafa Kasbari ◽  
Christian Rivero ◽  
Sylvain Blayac ◽  
Florian Cacho ◽  
Ola Bostrom ◽  
...  
Keyword(s):  
Mechanical Stress ◽  
Local Stress ◽  
Local Strain ◽  
Geometrical Model ◽  
Copper Interconnects ◽  
Cmos Process ◽  
Stress Monitoring ◽  
Curvature Measurement ◽  
The One

ABSTRACTA new mechanical stress characterization method has been developed for Damascene copper interconnects. The micro strain gauge based on a rotating beam has been fabricated in situ on a standard industrial CMOS production line. Comparison of the beam deviation in the fabricated sensor with usual geometrical model is discussed. The saturation of the beam deviation leads to an analytical model which takes the stiffness of the anchoring points into account. This model gives a direct value of the local stress in the copper line for different annealing times. We show that this value is different from the one given by a curvature measurement method. The microstructure of the Damascene copper induces a higher stress level than full sheet deposition copper. The sensor was developed to be compatible within a CMOS process. It is suitable for in situ mechanical stress monitoring in Damascene lines and process optimization.

Inter and Intra Granular Strain Analysis by Microdiffraction Kossel

2005 ◽  
Vol 490-491 ◽  
pp. 159-164 ◽  
Author(s):  
Sophie Berveiller ◽  
Pascal Dubos ◽  
Karim Inal ◽  
André Eberhardt ◽  
Etienne Patoor
Keyword(s):  
Physical Phenomenon ◽  
Strain Analysis ◽  
Ccd Camera ◽  
Local Stress ◽  
Tensile Tests ◽  
Stress And Strain ◽  
Constant Determination ◽  
Long Time ◽  
Crystallographic Planes

We have developed a new convenient tool for local stress and strain analysis in the scanning electron microscope. It is based on the Kossel diffraction, physical phenomenon that is known for a long time because of its high accuracy for lattice constant determination in micron regions. The pattern is recorded on a CCD camera allowing a fast and reliable analysis. This technique has been applied to several materials. In-situ tensile tests were performed on a shape memory alloy. During loading, we observe clearly a shift of Kossel lines on the diagram, whose magnitude depends on the (hkl) crystallographic planes. The stress can be deduced from the diffracting plane strain measurement using a single crystal stress analysis.

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