14 research outputs found
Interpretable and Robust AI in EEG Systems: A Survey
The close coupling of artificial intelligence (AI) and electroencephalography
(EEG) has substantially advanced human-computer interaction (HCI) technologies
in the AI era. Different from traditional EEG systems, the interpretability and
robustness of AI-based EEG systems are becoming particularly crucial. The
interpretability clarifies the inner working mechanisms of AI models and thus
can gain the trust of users. The robustness reflects the AI's reliability
against attacks and perturbations, which is essential for sensitive and fragile
EEG signals. Thus the interpretability and robustness of AI in EEG systems have
attracted increasing attention, and their research has achieved great progress
recently. However, there is still no survey covering recent advances in this
field. In this paper, we present the first comprehensive survey and summarize
the interpretable and robust AI techniques for EEG systems. Specifically, we
first propose a taxonomy of interpretability by characterizing it into three
types: backpropagation, perturbation, and inherently interpretable methods.
Then we classify the robustness mechanisms into four classes: noise and
artifacts, human variability, data acquisition instability, and adversarial
attacks. Finally, we identify several critical and unresolved challenges for
interpretable and robust AI in EEG systems and further discuss their future
directions
Cracking Behavior, Microstructure and Properties of Selective Laser Melted Al-Mn-Mg-Sc-Zr Alloy
In this paper, the cracking of Al-Mn-Mg-Sc-Zr alloys prepared by selective laser melting (SLM) was comprehensively explored and the influence of process parameters on the generation and propagation of cracks was deeply studied. It was found that the higher laser power and volume energy density will lead to a decrease in the relative density of the material. The lower laser power or volume energy density will lead to cracking of the alloy. The microstructure analysis indicated that plenty of manganese-rich second phases precipitated at the bottom of the melt pool, which increased the tendency of cracking occurred at the bottom of the melt pool. Through the optimization of the process parameters, the SLM forming process parameters of the Al-5.22Mn-1.16Mg-0.81Sc-0.46Zr alloy are successfully obtained, and the crack-free tensile samples are prepared. The microstructure and mechanical properties of the as-deposited aluminum-manganese alloy is analyzed. The bottom and inside of the melt pool are equiaxed grains. The size of the equiaxial grains at the bottom of the melt pool is less than 2 μm, and the coarse equiaxial grains inside the melt pool are approximately 5 μm. As-deposited alloy has a room temperature tensile strength of 455.2 ± 0.7 MPa and elongation of 15.4 ± 0.3%. This study provides guidance for selective laser melting forming of high-strength aluminum-manganese alloy parts, and promotes the industrial production of high-strength aluminum alloy near net forming complex parts
Cracking Behavior, Microstructure and Properties of Selective Laser Melted Al-Mn-Mg-Sc-Zr Alloy
In this paper, the cracking of Al-Mn-Mg-Sc-Zr alloys prepared by selective laser melting (SLM) was comprehensively explored and the influence of process parameters on the generation and propagation of cracks was deeply studied. It was found that the higher laser power and volume energy density will lead to a decrease in the relative density of the material. The lower laser power or volume energy density will lead to cracking of the alloy. The microstructure analysis indicated that plenty of manganese-rich second phases precipitated at the bottom of the melt pool, which increased the tendency of cracking occurred at the bottom of the melt pool. Through the optimization of the process parameters, the SLM forming process parameters of the Al-5.22Mn-1.16Mg-0.81Sc-0.46Zr alloy are successfully obtained, and the crack-free tensile samples are prepared. The microstructure and mechanical properties of the as-deposited aluminum-manganese alloy is analyzed. The bottom and inside of the melt pool are equiaxed grains. The size of the equiaxial grains at the bottom of the melt pool is less than 2 μm, and the coarse equiaxial grains inside the melt pool are approximately 5 μm. As-deposited alloy has a room temperature tensile strength of 455.2 ± 0.7 MPa and elongation of 15.4 ± 0.3%. This study provides guidance for selective laser melting forming of high-strength aluminum-manganese alloy parts, and promotes the industrial production of high-strength aluminum alloy near net forming complex parts
Research on Microstructure and Properties of AlSi10Mg Fabricated by Selective Laser Melting
In order to obtain high-performance aluminum alloy parts fabricated by selective laser melting, this paper investigates the relationship between the process parameters and microstructure properties of AlSi10Mg. The appropriate process parameters are obtained: the layer thickness is 0.03 mm, the laser power is 370 W, the scanning speed is 1454 mm/s, and the hatch spacing is 0.16 mm. With these process parameters, the ultimate tensile strength of the as-printed status is 500.7 ± 0.8 MPa, the yield strength is 311.5 ± 5.9 MPa, the elongation is 7.7 ± 0.5%, and the relative density is 99.94%. After annealing treatment at 275 °C for 2 h, the ultimate tensile strength is 310.8 ± 1.3 MPa, the yield strength is 198.0 ± 2.0 MPa, and the elongation is 13.7 ± 0.6%. The mechanical properties are mainly due to the high relative density, supersaturate solid solution, and fine dispersed Si. The supersaturate solid solution and nano-sized Si formed by the high cooling rate of SLM. After annealing treatment, the Si have been granulated and grown significantly. The ultimate tensile strength and yield strength are reduced, and the elongation is significantly improved
Recommended from our members
Using an animal model to predict the effective human dose for oral multiple sclerosis drugs.
The objective of this study was to determine the potential usefulness of an animal model to predict the appropriate dose of newly developed drugs for treating relapsing remitting multiple sclerosis (RRMS). Conversion of the lowest effective dose (LEffD) for mice and rats in the experimental autoimmune encephalomyelitis (EAE) model was used to predict the human effective dose utilizing the body surface area correction factor found in the 2005 US Food and Drug Administration (FDA) Guidance for Industry in selecting safe starting doses for clinical trials. Predictions were also tested by comparison with doses estimated by scaling up the LEffD in the model by the human to animal clearance ratio. Although initial proof-of-concept studies of oral fingolimod tested the efficacy and safety of 1.25 and 5 mg in treating RRMS, the EAE animal model predicted the approved dose of this drug, 0.5 mg daily. This approach would have also provided useful predictions of the approved human oral doses for cladribine, dimethyl fumarate, ozanimod, ponesimod, siponimod, and teriflunomide, drugs developed with more than one supposed mechanism of action. The procedure was not useful for i.v. dosed drugs, including monoclonal antibodies. We maintain that drug development scientists should always examine a simple allometric method to predict the therapeutic effective dose in humans. Then, following clinical studies, we believe that the animal model might be expected to yield useful predictions of other drugs developed to treat the same condition. The methodology may not always be predictive, but the approach is so simple it should be investigated
The Ratio of the Hemoglobin to Red Cell Distribution Width Combined with the Ratio of Platelets to Lymphocytes Can Predict the Survival of Patients with Gastric Cancer Liver Metastasis
Background. Hemoglobin/red cell distribution width (HR) and platelet/lymphocyte (PLR) ratios are considered effective prognostic markers in various cancers. We have proposed a new prognostic parameter: HR+PLR. The aim of this study is to explore the prognostic value of the HR+PLR scoring system in patients with gastric cancer liver metastasis. Methods. This study retrospectively analyzed the clinical data of 306 patients with gastric cancer liver metastases admitted to our hospital from 2007 to 2014. According to the size of HR value and PLR value, we will divide the patients into three groups, namely, HR+PLR: (1) 0 points: HR>1.02 and PLR1.02 and PLR>128 and HR128. Results. The HR+PLR score was statistically different from age (P=0.049), T stage (P<0.001), N stage (P=0.017), number of liver metastases (P=0.018), gastrectomy (P<0.001), hepatectomy (P=0.001), peritoneal metastasis (P=0.012), prognostic nutritional index (PNI) (P=0.028), and neutrophil/lymphocyte ratio (NLR) (P=0.045). The HR+PLR scoring system has a higher area under the ROC curve (AUC value) than PNI, PLR, HR, and PLR (AUC=0.798, P<0.001). In multivariate analysis, gastrectomy (P=0.001), hepatectomy (P<0.001), chemotherapy (P=0.014), and HR+PLR score (P<0.001) were considered independent prognostic factors. Conclusion. For patients with gastric cancer liver metastasis, the HR+PLR score is a simple, reliable, and economic prognostic marker
MoS2-Based Photodetectors Powered by Asymmetric Contact Structure with Large Work Function Difference
Abstract Self-powered devices are widely used in the detection and sensing fields. Asymmetric metal contacts provide an effective way to obtain self-powered devices. Finding two stable metallic electrode materials with large work function differences is the key to obtain highly efficient asymmetric metal contacts structures. However, common metal electrode materials have similar and high work functions, making it difficult to form an asymmetric contacts structure with a large work function difference. Herein, Mo2C crystals with low work function (3.8 eV) was obtained by chemical vapor deposition (CVD) method. The large work function difference between Mo2C and Au allowed us to synthesize an efficient Mo2C/MoS2/Au photodetector with asymmetric metal contact structure, which enables light detection without external electric power. We believe that this novel device provides a new direction for the design of miniature self-powered photodetectors. These results also highlight the great potential of ultrathin Mo2C prepared by CVD in heterojunction device applications
Cell type–specific cytonuclear coevolution in three allopolyploid plant species
Cytonuclear disruption may accompany allopolyploid evolution as a consequence of the merger of different nuclear genomes in a cellular environment having only one set of progenitor organellar genomes. One path to reconcile potential cytonuclear mismatch is biased expression for maternal gene duplicates (homoeologs) encoding proteins that target to plastids and/or mitochondria. Assessment of this transcriptional form of cytonuclear coevolution at the level of individual cells or cell types remains unexplored. Using single-cell (sc-) and single-nucleus (sn-) RNAseq data from eight tissues in three allopolyploid species, we characterized cell type–specific variations of cytonuclear coevolutionary homoeologous expression and demonstrated the temporal dynamics of expression patterns across development stages during cotton fiber development. Our results provide unique insights into transcriptional cytonuclear coevolution in plant allopolyploids at the single-cell level.This article is published as Zhang, Keren, Xueru Zhao, Yue Zhao, Zhibin Zhang, Zhijian Liu, Ziyu Liu, Yanan Yu et al. "Cell type–specific cytonuclear coevolution in three allopolyploid plant species." Proceedings of the National Academy of Sciences 120, no. 40 (2023): e2310881120. doi:10.1073/pnas.2310881120. Copyright © 2023 the Author(s). Posted with permission.This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND)