91 research outputs found
Static and free vibration analyses of plates on elastic foundation using a cell-based smoothed three-node mindlin plate element (CS-Min3)
A cell-based smoothed three-node Mindlin plate element (CS-MIN3) was recently proposed to improve the performance of the existing three-node Mindlin plate element (MIN3) for static and free vibration analyses of Mindlin plates. In this paper, the CSMIN3 is incorporated with spring systems for treating more complicated static and free vibration analyses of Mindlin plates on the elastic foundation. The plate-foundation system is modeled as a discretization of triangular plate elements supported by discrete springs at the nodal points representing the elastic foundation. The accuracy and reliability of the proposed method are verified by comparing with those of others available numerical results
Feature-based Learning for Diverse and Privacy-Preserving Counterfactual Explanations
Interpretable machine learning seeks to understand the reasoning process of
complex black-box systems that are long notorious for lack of explainability.
One flourishing approach is through counterfactual explanations, which provide
suggestions on what a user can do to alter an outcome. Not only must a
counterfactual example counter the original prediction from the black-box
classifier but it should also satisfy various constraints for practical
applications. Diversity is one of the critical constraints that however remains
less discussed. While diverse counterfactuals are ideal, it is computationally
challenging to simultaneously address some other constraints. Furthermore,
there is a growing privacy concern over the released counterfactual data. To
this end, we propose a feature-based learning framework that effectively
handles the counterfactual constraints and contributes itself to the limited
pool of private explanation models. We demonstrate the flexibility and
effectiveness of our method in generating diverse counterfactuals of
actionability and plausibility. Our counterfactual engine is more efficient
than counterparts of the same capacity while yielding the lowest
re-identification risks
Etiology and epidemiology of diarrhea in children in Hanoi, Vietnam
SummaryObjectivesThis paper provides a preliminary picture of diarrhea with regards to etiology, clinical symptoms, and some related epidemiologic factors in children less than five years of age living in Hanoi, Vietnam.MethodsThe study population included 587 children with diarrhea and 249 age-matched healthy controls. The identification of pathogens was carried out by the conventional methods in combination with ELISA, immunoseparation, and PCR. The antibiotic susceptibility was determined by MIC following the NCCLS recommendations.ResultsOf those with diarrhea, 40.9% were less than one year old and 71.0% were less than two years old. A potential pathogen was identified in 67.3% of children with diarrhea. They were group A rotavirus, diarrheagenic Escherichia coli, Shigella spp, and enterotoxigenic Bacteroides fragilis, with prevalences of 46.7%, 22.5%, 4.7%, and 7.3%, respectively. No Salmonella spp or Vibrio cholerae were isolated. Rotavirus and diarrheagenic E. coli were predominant in children less than two years of age, while Shigella spp, and enterotoxigenic B. fragilis were mostly seen in the older children. Diarrheagenic E. coli and Shigella spp showed high prevalence of resistance to ampicillin, chloramphenicol, and to trimethoprim/sulfamethoxazole. Children attending the hospitals had fever (43.6%), vomiting (53.8%), and dehydration (82.6%). Watery stool was predominant with a prevalence of 66.4%, followed by mucous stool (21.0%). The mean episodes of stools per day was seven, ranging from two to 23 episodes. Before attending hospitals, 162/587 (27.6%) children had been given antibiotics. Overall, more children got diarrhea in (i) poor families; (ii) families where piped water and a latrine were lacking; (iii) families where mothers washed their hands less often before feeding the children; (iv) families where mothers had a low level of education; (v) families where information on health and sanitation less often reached their households.ConclusionsGroup A rotavirus, diarrheagenic Escherichia coli, Shigella spp, and enterotoxigenic Bacteroides fragilis play an important role in causing diarrhea in children in Hanoi, Vietnam. Epidemiological factors such as lack of fresh water supply, unhygienic septic tank, low family income, lack of health information, and low educational level of parents could contribute to the morbidity of diarrhea in children
Flat Seeking Bayesian Neural Networks
Bayesian Neural Networks (BNNs) provide a probabilistic interpretation for
deep learning models by imposing a prior distribution over model parameters and
inferring a posterior distribution based on observed data. The model sampled
from the posterior distribution can be used for providing ensemble predictions
and quantifying prediction uncertainty. It is well-known that deep learning
models with lower sharpness have better generalization ability. However,
existing posterior inferences are not aware of sharpness/flatness in terms of
formulation, possibly leading to high sharpness for the models sampled from
them. In this paper, we develop theories, the Bayesian setting, and the
variational inference approach for the sharpness-aware posterior. Specifically,
the models sampled from our sharpness-aware posterior, and the optimal
approximate posterior estimating this sharpness-aware posterior, have better
flatness, hence possibly possessing higher generalization ability. We conduct
experiments by leveraging the sharpness-aware posterior with state-of-the-art
Bayesian Neural Networks, showing that the flat-seeking counterparts outperform
their baselines in all metrics of interest.Comment: Accepted at NeurIPS 202
Analyses of stiffened plates resting on the viscoelastic foundation subjected to a moving vehicle by a cell-based smoothed triangular plate element
Recently, a cell-based smoothed discrete shear gap method (CS-FEM-DSG3) based on the firstorder shear deformation theory (FSDT) was proposed for static and free vibration analyses of Mindlin plates. The CS-FEM-DSG3 uses three-node triangular elements that can be easily generated automatically for arbitrary complicated geometric domains. This paper further extends the CS-FEMDSG3 for static, free vibration, and dynamic response of the stiffened plate resting on viscoelastic foundation subjected to a moving vehicle. The viscoelastic foundation is modeled by discrete springs and dampers whereas the stiffened plate can be considered as the combination between the Mindlin plate and the Timoshenko beam elements. The moving vehicle is transformed into one concentrated load at its central point. Some numerical examples are investigated and numerical results show that the CS-FEMDSG3 overcomes shear-locking phenomena and has a fast convergence. The results also illustrate the good agreement of the CS-FEM-DSG3 for static and free vibration analyses of un-stiffened plate compared with the previous published methods. In addition, the numerical results for dynamic analysis of stiffened plates by the CS-FEM-DSG3 also show the expected property in which the deflection of the stiffened plate is much smaller than those of the un-stiffened plate
Synthesis and Characterization of RbxMn[Fe(CN)]6 and Mn3[Cr(CN)6]2
We present the synthesis and detailed characterization of RbxMn[Fe(CN)]6 and Mn3[Cr(CN)6]2 compounds. The composition of the materials significantly depends on the preparation conditions. Analysis of Raman spectroscopic results and X-ray powder diffraction data yielded a further assessment of the changes in structural features. The characteristic individual magnetic behavior, as well as the metal-to-metal charge-transfer capabilities of the various samples, could be related to significant changes within the structure that appear to be associated with the synthesis method used
A Measure of Smoothness in Synthesized Speech
The articulators typically move smoothly during speech production. Therefore, speech features of natural speech are generally smooth. However, over-smoothness causes "muffleness" and, hence, reduction in ability to identify emotions/expressions/styles in synthesized speech that can affect the perception of naturalness in synthesized speech. In the literature, statistical variances of static spectral features have been used as a measure of smoothness in synthesized speech but they are not sufficient enough. This paper proposes another measure of smoothness that can be efficiently applied to evaluate the smoothness of synthesized speech. Experiments showed that the proposed measure is reliable and efficient to measure the smoothness of different kinds of synthesized speech
Classification of cow’s behaviors based on 3-DoF accelerations from cow’s movements
Cow’s behavior classification helps people to monitor cow activities, thus the health and physiological periods of cows can be well tracked. To classify the behavior of cows, the data from the 3-axis acceleration sensor mounted on their neck is often used. Data acquisition and preprocessing of sensor data is required in this device. We acquire data from the 3-axis acceleration sensor mounted on the cows’neck and send to the microcontrollter. At the microcontroller, a proposed decision tree is applied in real-time manner to classify four important activities of the cows (standing, lying, feeding, and walking). Finally, the results can be sent to the server through the wireless transmission module. The test results confirm the reliability of the proposed device
A modern purification by accelerated solvent extraction and centrifugal partition chromatography and biological evaluation of capsaicin from Capsicum chinense
A special alkaloid compound known as capsaicin, which can only be found in the fruit of the Capsicum plant, was isolated and tested for its anti-inflammatory activity. The purpose of this work is to establish a simple and quick approach for capsaicin purification utilizing centrifugal partition chromatography (CPC) as well as an effective method - accelerated solvent extraction (ASE), for extracting capsaicin from Capsicum chinense. After purification, capsaicin was validated by HPLC-DAD at 281 nm to be > 90% purity. The in vivo anti-inflammatory activity of the isolated capsaicin was also investigated, and the IC50 value of the capsaicin was determined to be 57.61 µg/mL. The current work emphasizes how an ASE and CPC system may combine to extract high-purity capsaicin from Capsicum chinense, which have the anti-inflammatory activity, as we evaluated in the experiment
Some chalcones derived from thio-phene-3-carbaldehyde: synthesis and crystal structures.
The synthesis, spectroscopic data and crystal and mol-ecular structures of four 3-(3-phenyl-prop-1-ene-3-one-1-yl)thio-phene derivatives, namely 1-(4-hydroxy-phen-yl)-3-(thio-phen-3-yl)prop-1-en-3-one, C13H10O2S, (1), 1-(4-meth-oxy-phen-yl)-3-(thio-phen-3-yl)prop-1-en-3-one, C14H12O2S, (2), 1-(4-eth-oxy-phen-yl)-3-(thio-phen-3-yl)prop-1-en-3-one, C15H14O2S, (3), and 1-(4--bromophen-yl)-3-(thio-phen-3-yl)prop-1-en-3-one, C13H9BrOS, (4), are described. The four chalcones have been synthesized by reaction of thio-phene-3-carbaldehyde with an aceto-phenone derivative in an absolute ethanol solution containing potassium hydroxide, and differ in the substituent at the para position of the phenyl ring: -OH for 1, -OCH3 for 2, -OCH2CH3 for 3 and -Br for 4. The thio-phene ring in 4 was found to be disordered over two orientations with occupancies 0.702 (4) and 0.298 (4). The configuration about the C=C bond is E. The thio-phene and phenyl rings are inclined by 4.73 (12) for 1, 12.36 (11) for 2, 17.44 (11) for 3 and 46.1 (6) and 48.6 (6)° for 4, indicating that the -OH derivative is almost planar and the -Br derivative deviates the most from planarity. However, the substituent has no real influence on the bond distances in the α,β-unsaturated carbonyl moiety. The mol-ecular packing of 1 features chain formation in the a-axis direction by O-H⋯O contacts. In the case of 2 and 3, the packing is characterized by dimer formation through C-H⋯O inter-actions. In addition, C-H⋯π(thio-phene) inter-actions in 2 and C-H⋯S(thio-phene) inter-actions in 3 contribute to the three-dimensional architecture. The presence of C-H⋯π(thio-phene) contacts in the crystal of 4 results in chain formation in the c-axis direction. The Hirshfeld surface analysis shows that for all four derivatives, the highest contribution to surface contacts arises from contacts in which H atoms are involved
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