Staircase effect in field-induced metamagnetic transitions in La0·9Ce0·1Fe12B6

2022 ◽  
Vol 341 ◽  
pp. 114568
Author(s):  
L.V.B. Diop ◽  
O. Isnard
Keyword(s):  
Staircase Effect

Improving Staircase Effect in the Process of Ceramic Laser Gelling

2011 ◽  
Vol 284-286 ◽  
pp. 43-47
Author(s):  
Hsiao Chuan Yen ◽  
Hwa Hsing Tang ◽  
Chun Hung Wu
Keyword(s):  
Water Content ◽  
Casting Process ◽  
High Water ◽  
Thin Layers ◽  
High Water Content ◽  
Layer Manufacturing ◽  
Staircase Effect ◽  
Alumina Particles ◽  
Ceramic Laser ◽  
Average Size

Based on ceramic laser gelling process, the purpose of this research is to obtain a proper slurry, which can be employed to cast layer with a thickness smaller than 100 μm to improve the staircase effect occurred in layer manufacturing, by optimization of the water content to fabricate ceramic part with better surface. The slurry was composed of alumina particles with average size of 0.5 μm as the structure element, silica sol as an inorganic binder and ammonium polymethacrylate as a dispersant. The slurry was dispersed uniformly by a ball mill. The results revealed the variation of water content will significantly influence the viscosity of the slurry and the formability of the ceramic green part. High water content led to poor binding of the particles and induced the delamination of the consolidated layers. On the contrary, low water content led to high shear force between scraper and slurry surface; such force damaged the previous layer during the casting process. As a result, the water content of 34 wt% was the most favorable to casting thin layers. The capability of casting 40 μm layer, which is smaller than that obtained by previous studies, was achieved. Because of the thinner layer, the staircase effect was improved.

A compensating total variation image denoising model combining L1 and L2 norm

2020 ◽  
pp. 002072092092330
Author(s):  
Liqiong Zhang ◽  
Min Li ◽  
Xiaohua Qiu
Keyword(s):  
Image Denoising ◽  
Total Variation ◽  
Structural Information ◽  
Signal To Noise Ratio ◽  
Similarity Index ◽  
Structural Similarity ◽  
Isotropic Diffusion ◽  
Model Combining ◽  
L2 Norm ◽  
Staircase Effect

To overcome the “staircase effect” while preserving the structural information such as image edges and textures quickly and effectively, we propose a compensating total variation image denoising model combining L1 and L2 norm. A new compensating regular term is designed, which can perform anisotropic and isotropic diffusion in image denoising, thus making up for insufficient diffusion in the total variation model. The algorithm first uses local standard deviation to distinguish neighborhood types. Then, the anisotropic diffusion based on L1 norm plays the role of edge protection in the strong edge region. The anisotropic and the isotropic diffusion simultaneously exist in the smooth region, so that the weak textures can be protected while overcoming the “staircase effect” effectively. The simulation experiments show that this method can effectively improve the peak signal-to-noise ratio and obtain the higher structural similarity index and the shorter running time.

scholarly journals Application of Vacuum Techniques in Shell Moulds Produced by Additive Manufacturing

Metals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1090
Author(s):  
P. Rodríguez-González ◽  
P. E. Robles Valero ◽  
A. I. Fernández-Abia ◽  
M. A. Castro-Sastre ◽  
J. Barreiro García
Keyword(s):  
Additive Manufacturing ◽  
Cross Section ◽  
Dimensional Accuracy ◽  
Filling Process ◽  
Critical Aspect ◽  
Entire Surface ◽  
Vacuum Suction ◽  
Staircase Effect ◽  
Gas Entrapment ◽  
Binder Jetting

This research shows the feasibility of the additive manufacturing technique (AM), Binder Jetting (BJ), for the production of shell moulds, which are filled by vacuum suction in the field of aluminium parts production. In addition, this study compares the gravity pouring technique and highlights the advantages of using vacuum techniques in AM moulds. A numerical simulation was carried out to study the behaviour of the liquid metal inside the moulds and the cooling rate of parts was analysed. The results show that in the gravity-pouring mould, the velocity in the gate causes moderate turbulence with small waves. However, vacuum suction keeps the velocity constant by eliminating waves and the filling process is homogeneous. Regarding dimensional accuracy, the staircase effect on the surface of the 3D moulds was the most critical aspect. The vacuum provides very homogeneous values of roughness across the entire surface of the part. Similarly, 3D scanning of castings revealed more accurate dimensions thanks to the help of vacuum forces. Finally, the microstructure of the cross section of the moulded parts shows that the porosity decreases with the vacuum filled. In both cases, the origin of the pores corresponds to gas entrapment and shrinkage during the filling process, the binder vaporization and nucleation points creation, leading to pores by shrinkage, gas entrapment or a mixture of both. This is the first study that uses vacuum filling techniques in moulds created by BJ, demonstrating the feasibility and advantages of AM using vacuum techniques, as an alternative to traditional casting.

Flow-dependent influence of high-O2-affinity erythrocytes on peak VO2 in exercising muscle in situ

1996 ◽  
Vol 80 (3) ◽  
pp. 832-838 ◽  
Author(s):  
H. Kohzuki ◽  
Y. Enoki ◽  
K. Matsumura ◽  
S. Sakata ◽  
S. Shimizu
Keyword(s):  
O2 Uptake ◽  
High Affinity ◽  
Staircase Effect ◽  
Citrate Phosphate Dextrose ◽  
High O2 ◽  
Rate Of Decline ◽  
O2 Delivery ◽  
Citrate Phosphate ◽  
Peak Value

To evaluate the influence of a high-O2 affinity of the erythrocyte and of flow rate on muscle's ability to extract O2 and develop force, we perfused dog gastrocnemius contracting isometrically at 4 Hz with normal-O2-affinity perfusate or high-O2-affinity perfusate at high and moderate flows (200 and 100 ml . min-1 . 100g-1, respectively). High-O2-affinity perfusate was prepared by incubating human citrate-phosphate-dextrose-stored erythrocytes with buffered saline containing cyanate (4 degrees C, 18 h) and normal-affinity perfusate by storing 2,3-diphosphoglycerate-rejuvenated erythrocytes in the same solution without cyanate. PO2 when blood is half oxygenated was 30.6 Torr for normal perfusate and 18.1 Torr for high-affinity perfusate. During 4-Hz stimulation, the tension developed by the muscle increased incrementally (positive staircase) to reach a peak value after 1.2-1.6 min for the normal perfusate and 0.6-0.7 min for the high-affinity perfusate (P < 0.05). The rate of decline during the early fatigue (measured from the onset of tension decline to 3 min) with high-affinity perfusate was significantly faster than it was with normal perfusate (P < 0.05). These findings suggest that both the staircase effect and the early fatigue are related to O2 availability, which is restricted when erythrocytes have a high O2 affinity. The peak O2 uptake values measured at 3 and 5 min were significantly lower (by 14-24%) with high-affinity perfusate than with normal perfusate at a given level of O2 delivery (arterial O2 content x flow) (P < 0.05). PO2 of venous effluent was proportionally related to peak O2 uptake. The present results indicate that neither blood flow nor O2 delivery is the sole determinant of the muscle's ability to extract O2.

Linear dependence of muscle phosphocreatine kinetics on total creatine content

1989 ◽  
Vol 257 (6) ◽  
pp. C1149-C1157 ◽  
Author(s):  
R. A. Meyer
Keyword(s):  
Linear Models ◽  
Adenine Nucleotide ◽  
Respiratory Control ◽  
Staircase Effect ◽  
Total Creatine ◽  
Creatine Kinase Reaction ◽  
Gastrocnemius Muscles ◽  
The Relationship ◽  
Hydrolysis Of ◽  
Stimulation Of

Phosphorus nuclear magnetic resonance (NMR) spectra and twitch tension were recorded during stimulation of gastrocnemius muscles of pentobarbital sodium-anesthetized rats which had been fed the creatine analogue beta-guanidinopropionic acid (beta-GPA, 2% diet) for periods from 0 (control) to 8 wk. Total creatine content of unstimulated muscles decreased by 42, 67, 82, and 88% compared with controls after 2-, 4-, 6-, and 8-wk feeding, respectively. The staircase effect observed in control muscles during 8 min of twitch stimulation at 0.25, 0.5, and 0.75 Hz was reduced after 2- to 8-wk beta-GPA feeding. However, after 6- to 8-wk feeding, the twitch force at the end of 8 min of stimulation was not different from controls. The time constant for phosphocreatine (PCr) changes at the onset of and during recovery after stimulation was proportional to total creatine content. The relationship between PCr content and twitch rate times force at the end of stimulation was linear, with slope proportional to total creatine content. PCr content in beta-GPA-fed animals was transiently greater during recovery than before stimulation, suggesting a regulatory effect of the inorganic phosphate released by hydrolysis of phosphorylated beta-GPA. The results are consistent with linear models of respiratory control in which the creatine kinase reaction acts as a simple buffer of adenine nucleotide levels.

Direct 3D Layer Metal Deposition and Toolpath Generation

2008 ◽  
Author(s):  
Jianzhong Ruan ◽  
Lie Tang ◽  
Todd E. Sparks ◽  
Robert G. Landers ◽  
Frank Liou
Keyword(s):  
Solid Freeform Fabrication ◽  
Deposition Method ◽  
Single Track ◽  
Uniform Thickness ◽  
Post Processing ◽  
Freeform Fabrication ◽  
Manufacturing Efficiency ◽  
Layer Deposition ◽  
Staircase Effect ◽  
Parallel Layer

Multi-axis slicing for solid freeform fabrication (SFF) manufacturing process can yield non-uniform thickness layers, or 3-D layers. Using the traditional parallel layer construction approach to build such a layer leads to a staircase which requires machining or other post processing to form the desired shape. This paper presents a direct 3-D layer deposition approach. This approach uses an empirical model to predict the layer thickness based on experimental data. The toolpath between layers is not parallel; instead, it follows the final shape of the designed geometry and the distance between the toolpath in the adjacent layers varies at different locations. Directly depositing a 3-D layer not only eliminates the staircase effect, but also improves the manufacturing efficiency by shortening the deposition and machining times. A single track deposition experiment has demonstrated these advantages. Thus, it is a beneficial addition to the traditional parallel deposition method.

scholarly journals An Efficient Algorithm for Reconstruction Images Corrupted by Some Multiplicative Noises

2019 ◽  
Vol 5 (2) ◽  
pp. 263-278
Author(s):  
L. Ziad ◽  
O. Oubbih ◽  
F. Sniba
Keyword(s):  
Multiplicative Noise ◽  
Slow Growth ◽  
Mathematical Framework ◽  
Well Posedness ◽  
Multiplicative Noises ◽  
Proposed Model ◽  
Staircase Effect ◽  
Map Estimator ◽  
Denoised Image ◽  
Numerical Approaches

AbstractIn this paper, we propose a novel hybrid model for restoration of images corrupted by multiplicative noise. Using a MAP estimator, we can derive a functional whose minimizer corresponds to the denoised image we want to recover. The energies studied here are inspired by image restoration with non linear variable exponent [1, 2], and it is a combination of fast growth with respect to low gradient and slow growth when the gradient is large. We study a mathematical framework to prove the well posedness of the minimizer problem and we introduce the associated evolution problem, for which we derive numerical approaches. At last, compared experimental results distinctly demonstrate the superiority of the proposed model, in term of removing some muliplicative noise while preserving the edges and reducing the staircase effect.

scholarly journals Disparity Optimization Algorithm for Stereo Matching Using Improved Guided Filter

2019 ◽  
Vol 23 (4) ◽  
pp. 625-633
Author(s):  
Yanyan Xu ◽  
◽  
Xiangyang Xu ◽  
Rui Yu
Keyword(s):  
Optimization Algorithm ◽  
Stereo Matching ◽  
Optimization Method ◽  
Guided Filter ◽  
Data Sets ◽  
Disparity Map ◽  
Segment Tree ◽  
Staircase Effect ◽  
Gradient Domain ◽  
Domain Information

A disparity optimization algorithm based on an improved guided filter is proposed to smooth the disparity image. A well-known problem to local stereo matching is the low matching accuracy and staircase effect in regions with weak texture and slope. Our disparity optimization method solves this problem and achieve a smooth disparity. First, the initial disparity image is obtained by a local stereo matching algorithm using segment tree. Then, the guided filter is improved by using gradient domain information. Lastly, the improved guided filter is adopted as the disparity optimization method to smooth the disparity image. Experiments conducted on the Middlebury data sets demonstrate that by using the proposed algorithm in this paper, the smoothness of the disparity map in slope regions is improved, and a higher precision of dense disparity is obtained.

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