thickness reduction
Recently Published Documents


TOTAL DOCUMENTS

286
(FIVE YEARS 89)

H-INDEX

17
(FIVE YEARS 4)

2022 ◽  
Vol 2161 (1) ◽  
pp. 012040
Author(s):  
Sourav Roy ◽  
Siddheswar Maikap

Abstract A performance improvement by reduction in switching material thickness in a e-gun deposited SiOx based resistive switching memory device was investigated. Reduction in thickness cause thinner filamentary path formation during ON-state by controlling the vacancy defects. Thinner filament cause lowering of operation current from 500 μA to 100 μA and also improves the reset current (from >400 μA to <100 μA). Switching material thickness reduction also cause the forming free ability in the device. All these electrical parametric improvements enhance the device reliability performances. The device show >200 dc endurance, >3-hour data retention and >1000 P/E endurance with 100 ns pulses.


Author(s):  
K Woloszyk ◽  
Y Garbatov

The work is focused on the reliability of corroded stiffened plates subjected to compressive uniaxial load based on the progressive collapse approach as stipulated by the Common Structural Rules for Bulk Carriers and Oil Tankers, employing the limit state design. Two different cases have been investigated. In the first model, the corrosion degradation led to uniform thickness loss, whereas the mechanical properties were unchanged, as given in the Rules. In the second model, the plate thickness degradation was followed by mechanical properties reduction. The uncertainties related to the mechanical properties, thicknesses, and initial imperfections of the corroded stiffened plate were taken into account. Several initial design solutions of stiffened plates, as well as different severity levels of corrosion degradation were investigated. The results show that structural reliability significantly decreases with corrosion development, especially when in addition to the initial imperfections and corrosion plate thickness reduction, corroded plate surface roughness and the changes in the mechanical properties were considered. The uncertainties, their origins and confidence levels are discussed. It was found that non-linear time-dependent corrosion degradation accounting not only for the thickness reduction due to corrosion wastage but also the subsequent decrease of mechanical properties lead to a significant reduction in the reliability index. Additionally, it was defined that the reliability estimate is very sensitive to the uncertainties related to the initial thickness and the spread of corrosion degradation as a function of the time. Incorporating the probability of corrosion detection into the original reliability model introduces additional information about the validity of structural degradation that may lead to a higher beta reliability index estimate compared to the original model.


2021 ◽  
pp. 1-27
Author(s):  
Xianghua Meng ◽  
Jing Wang ◽  
Gyoko Nagayama

Abstract Temperature rise and film thickness reduction are the most important factors in elastohydrodynamic lubrication (EHL). In the EHL contact area, interfacial resistances (velocity/thermal slips) induced by the molecular interaction between lubricant and solid become significant due to the large surface/volume ratio. Although the velocity slip has been investigated extensively, less attention has been paid on the thermal slip in the EHL regime. In this study, numerical simulations were conducted by applying three cases of boundary slips to surfaces under sliding/rolling contacts moving in the same direction for the Newtonian thermal EHL. We found that the coupled velocity/thermal slips lead the most significant temperature rise and film thickness reduction among the three cases. The velocity slip results in a lower temperature in the lubricant and solids, whereas the thermal slip causes a temperature rise in the entire contact area as the film thickness decreases simultaneously. Furthermore, the effect of thermal slip on lubrication is more dominant than that of velocity slip while increases the entrainment velocity or slide–roll ratio.


2021 ◽  
Vol 904 ◽  
pp. 26-30
Author(s):  
Xia Zhu ◽  
Hiromichi Toyota ◽  
Hironori Hagio ◽  
Shigekiyo Ishikawa ◽  
Takahiro Akutagawa

This study investigated the stress and strain behavior caused in the forming process via simulation analysis using the finite element method, for suppressing punch shoulder and head plate thickness reduction die shoulder stress concentration by controlling the friction conditions. The following findings were obtained: The thickness of the blank head and punch shoulder decreased with the forming process. Due to the increase in the coefficient of friction with the punch side, the plate thickness reduction ratio decreases, and is the lowest when it is close to non-lubrication; Stress concentration occurs at the die shoulder with forming processing. With the increase in the friction coefficient value, forming limit parameter (FLP) increases slightly, but as it does not reach the limit value of 1, the forming process can be safely performed without mechanical damage; When the formability is comprehensively evaluated using the plate thickness reduction ratio and FLP, the friction coefficient μ = 0.4 to 0.5 is reasonable.


2021 ◽  
pp. 112067212110596
Author(s):  
Nadav Levinger ◽  
Liran Tiosano ◽  
Elishai Assayag ◽  
Rivkah Lender ◽  
Tomer Batash ◽  
...  

Purpose To evaluate whether outcome of bevacizumab treatment in the first treated eye can guide the selection of compound for the second treated eye in patients with bilateral diabetic macular edema. Methods Demographic, clinical, and optical coherence tomography data were retrospectively collected from consecutive patients who underwent bevacizumab therapy for bilateral diabetic macular edema. Change in central subfield thickness and visual acuity were evaluated and compared between the first treated eye and second treated eye. Results A total of 66 eyes of 33 patients were included in the study. The mean ± SD follow-up time was 13 ± 5 months. The mean ± SD central subfield thickness at baseline was 464 ± 30 μm in the first treated eye and 461 ± 29 μm in the second treated eye ( p = 0.91). Final central subfield thickness was reduced to 392 ± 27 μm in the first treated eye ( p = 0.01 compared with baseline) and 416 ± 25 μm in the second treated eye ( p = 0.03 compared with baseline). Using ≥5% or ≥10% reduction of central subfield thickness as diagnostic criteria to predict similar magnitude of thickness reduction in the first treated eye yielded a positive and negative predictive value ranging from 46% to 81%, and sensitivity and specificity ranging from 54% to 84%. Regression models did not show correlation between central subfield thickness reduction in first treated eye and the second treated eye at the end of follow-up. Conclusions Bevacizumab therapy reduced macular thickness in both eyes in bilateral diabetic macular edema. Treatment outcome of the first treated eye could not predict the outcome of the second treated eye. Particularly, failure to reduce central subfield thickness in the first treated eye does not preclude a favorable response to bevacizumab therapy in the second eye.


2021 ◽  
Author(s):  
Weiye Wu ◽  
Li Qiu ◽  
A. Abu-Siada ◽  
Chenglin Wang ◽  
Jinbo Jiang

Abstract In order to solve the problems of non-uniform axial deformation and thinning of wall thickness in traditional tube electromagnetic bulging, a method of tube electromagnetic bulging based on convex magnetic field shaper is proposed in this paper. The electromagnetic-structure coupling model is constructed by using COMSOL software, and the influence of convex magnetic field shaper structure on radial and axial electromagnetic force, axial deformation uniformity and wall thickness reduction is analyzed, and compared with traditional tube electromagnetic bulging. The results show that by using this method, the axial deformation uniformity is increased by 4.2 times, and the relative wall thickness is reduced by 33%. Obviously, this method of tube bulging can effectively overcome the problems existing in traditional tube electromagnetic bulging and promote the wide application of electromagnetic forming technology.


Sign in / Sign up

Export Citation Format

Share Document