879 research outputs found
Analysis and Mitigation of Soft-Errors on High Performance Embedded GPUs
Multiprocessor system-on-chip such as embedded
GPUs are becoming very popular in safety-critical applications,
such as autonomous and semi-autonomous vehicles. However,
these devices can suffer from the effects of soft-errors, such as
those produced by radiation effects. These effects are able to
generate unpredictable misbehaviors. Fault tolerance oriented to
multi-threaded software introduces severe performance
degradations due to the redundancy, voting and correction
threads operations. In this paper, we propose a new fault injection
environment for NVIDIA GPGPU devices and a fault tolerance
approach based on error detection and correction threads
executed during data transfer operations on embedded GPUs. The
fault injection environment is capable of automatically injecting
faults into the instructions at SASS level by instrumenting the
CUDA binary executable file. The mitigation approach is based on
concurrent error detection threads running simultaneously with
the memory stream device to host data transfer operations. With
several benchmark applications, we evaluate the impact of softerrors classifying Silent Data Corruption, Detection,
Unrecoverable Error and Hang. Finally, the proposed mitigation
approach has been validated by soft-error fault injection
campaigns on an NVIDIA Pascal Architecture GPU controlled by
Quad-Core A57 ARM processor (JETSON TX2) demonstrating
an advantage of more than 37% with respect to state of the art
solution
The effects of binaural spectral resolution mismatch on Mandarin speech perception in simulated electric hearing
This study assessed the effects of binaural spectral resolution mismatch on the intelligibility of Mandarin speech in noise using bilateral cochlear implant simulations. Noise-vocoded Mandarin speech, corrupted by speech-shaped noise at 0 and 5 dB signal-to-noise ratios, were presented unilaterally or bilaterally to normal-hearing listeners with mismatched spectral resolution between ears. Significant binaural benefits for Mandarin speech recognition were observed only with matched spectral resolution between ears. In addition, the performance of tone identification was more robust to noise than that of sentence recognition, suggesting factors other than tone identification might account more for the degraded sentence recognition in noise.published_or_final_versio
The application of a stockpile stochastic model into long-term open pit mine production scheduling to improve the feed grade for the processing plant
This paper presents a chance-constrained integer programming approach based on the linear method to solve the long-term open pit mine production scheduling problem. Specifically, a single stockpile has been addressed for storing excess low-grade material based on the availability of processing capacity and for possible future processing. The proposed scheduling model maximizes the project NPV while respecting a series of physical and economic constraints. Differently from common practice, where deterministic models are used to calculate the average grade for material in the stockpiles, in this work a stochastic approach was performed, starting from the time of planning before the stockpile realization. By performing a probability analysis on two case studies (on iron and gold deposits), it was proven that the stockpile attributes can be treated as normally distributed random variables. Afterwards, the stochastic programming model was formulated in an open pit gold mine in order to determine the optimum amount of ore dispatched from different bench levels in the open pit and at the same time a low-grade stockpile to the mill. The chance-constrained programming was finally applied to obtain the equivalent deterministic solution of the primary model. The obtained results have shown a better feed grade for the processing plant with a higher NPV and probability of grade blending constraint satisfaction, with respect to using the traditional stockpile deterministic model.
Remyelination of the corpus callosum by olfactory ensheathing cell in an experimental model of multiple sclerosis
Multiple Sclerosis (MS) causes loss of the myelin sheath, which leads to loss of neurons. Regeneration of myelin sheath stimulates axon regeneration and neurons� survival. In this study, olfactory ensheathing cell (OEC) transplantation is investigated to restore myelin sheath in an experimental model of MS in male mice.OECs were isolated from the olfactory mucosa of seven-day-old infant rats and cultured. Then, cells were evaluated and approved by flow cytometry by p75 and GFAP markers. A total of 32 mice (C57BL /6) were studied in four groups; 1) without any treatment (control), 2) Sham (receiving PBS), 3) MS model and 4) MS and OEC transplantation. MS was induced by adding Cuprizon in the diet of animals for six weeks. After the expiration of 20 days, histologic analysis was performed with approval of the presence of cells in the graft area and the removal of myelin and myelin regeneration with two types of luxal fast blue (LFB) staining and immunohistochemistry. The purity of the cells ensheathing the olfactory was 90. There was a significant difference in Myelin percentage of PBS and OEC recipient groups (P�0.05). MBP and PLP of the myelin sheath in the group receiving OECs were more than MS group.According to the findings, in MS model MBP and PLP of the myelin sheath is reduced. In the group receiving OECs, it was returned to a normal level significantly compared to the sham group received only PBS significant differences were observed. The OECs transplantation can improve myelin restoration. © 2015 Tehran University of Medical Sciences. All rights reserved
Statin therapy in chronic viral hepatitis: a systematic review and meta-analysis of nine studies with 195,602 participants
Background: Conflicting data suggest that statins could cause chronic liver disease in certain group of patients, while improving prognosis in those with chronic viral hepatitis (CVH).
Purpose: To quantify the potential protective role of statins on some main liver-related health outcomes in clinical studies on CVH patients.Data Sources: The search strategy was explored by a medical librarian using bibliographic databases, from January 2015 to April 2020.Data synthesis: The results showed no significant difference in the risk of mortality between statin users and non-users in the overall analysis. However, the risk of mortality significantly reduced by 39% in statin users who were followed for more than three years. Moreover, the risk of HCC, fibrosis, and cirrhosis in those on statins decreased by 53%, 45% and 41%, respectively. Although ALT and AST reduced slightly following statin therapy, this reduction was not statistically significant.
Limitations: A significant heterogeneity among studies was observed, resulting from differences in clinical characteristics between statin users and non-users, study designs, population samples, diseases stage, comorbidities, and confounding covariates.
Conclusion: Not only long-term treatment with statins seems to be safe in patients affected by hepatitis, but also it significantly improves their prognosis
Generating GHZ state in 2m-qubit spin network
We consider a pure 2m-qubit initial state to evolve under a particular
quantum me- chanical spin Hamiltonian, which can be written in terms of the
adjacency matrix of the Johnson network J(2m;m). Then, by using some techniques
such as spectral dis- tribution and stratification associated with the graphs,
employed in [1, 2], a maximally entangled GHZ state is generated between the
antipodes of the network. In fact, an explicit formula is given for the
suitable coupling strengths of the hamiltonian, so that a maximally entangled
state can be generated between antipodes of the network. By using some known
multipartite entanglement measures, the amount of the entanglement of the final
evolved state is calculated, and finally two examples of four qubit and six
qubit states are considered in details.Comment: 22 page
- …