536 research outputs found
Noise-Boosted Convolutional Neural Network for Edge-based Motor Fault Diagnosis with Limited Samples
Convolutional neural networks (CNNs) have been widely applied in motor fault diagnosis. However, to obtain high recognition accuracy, massive training data are typically required and transmitted to the cloud/local server for training, which may suffer from security and privacy problems. In this study, a noise-boosted CNN (NBCNN) model is developed to achieve accelerated training and improved recognition accuracy with limited training samples. First, the NBCNN model with a noise-injection fully connected layer is established. Then, a strategy for noise selection and injection is proposed to obtain an optimal matching among the data, model, and noise. Finally, the optimal injected noise accelerates the convergence of model training and improves the accuracy of motor fault diagnosis. Compared with the conventional CNN without noise injection and the state-of-the-art models, the effectiveness and superiority of the proposed NBCNN model are validated by two benchmark datasets. In addition, the algorithm is deployed onto an edge device and the results show that the training speed of the developed NBCNN can reach nine times faster than the conventional CNN. The proposed method shows remarkable potential for distributed model training, federal learning, and real-time motor fault diagnosis
Core-sheath nanofibers as drug delivery system for thermoresponsive controlled release
In this work, a smart drug delivery system of core–sheath nanofiber is reported. The core-sheath nanofibers were prepared with thermoresponsive poly-(N-isopropylacrylamide) (PNIPAAm) (as core) and hydrophobic ethylcellulose (EC) (as sheath) by coaxial electrospinning. Analogous medicated fibers were prepared by loading with a model drug ketoprofen (KET). The fibers were cylindrical without phase separation and have visible core-sheath structure as shown by scanning and transmission electron microscopy. X-ray diffraction patterns demonstrated the drug with the amorphous physical form was present in the fiber matrix. Fourier transform infrared spectroscopy analysis was conducted, finding that there were significant intermolecular interactions between KET and the polymers. Water contact angle measurements proved that the core-sheath fibers from hydrophobic transformed into hydrophobic when the temperature reached the lower critical solution temperature. In vitro drug-release study of nanofibers with KET displayed that the coaxial nanofibers were able to synergistically combine the characteristics of the two polymers producing a temperature-sensitive drug delivery system with sustained release properties. In addition, they were established to be non-toxic and suitable for cell growth. These findings show that the core–sheath nanofiber is a potential candidate for controlling drug delivery system
Mulberry Leaf Regulates Differentially Expressed Genes in Diabetic Mice Liver Based on RNA-Seq Analysis
The pathogenesis of diabetes mellitus is a complicated process involving much gene regulation. The molecular mechanism of mulberry (Morus alba L.) leaf in the treatment of diabetes is not fully understood. In this study, we used the Illumina HiSeq™ 2,500 platform to explore the liver transcriptome of normal mice, STZ-induced diabetic mice, and mulberry leaf-treated diabetic mice, and we obtained 52,542,956, 52,626,414, and 52,780,196 clean reads, respectively. We identified differentially expressed genes (DEGs) during the pathogenesis of diabetes in mice. The functional properties of DEGs were characterized by comparison with the GO and KEGG databases, and the results show that DEGs are mainly involved in the metabolic pathway. qRT-PCR was used to analyse 27 differential genes involved in liver expression in different groups of diabetic mice. Among the DEGs, the expression of Scube1, Spns3, Ly6a, Igf2, and other genes between the control (C) and diabetic control (DC) groups was significantly upregulated; the expression of Grb10, Mup2, and Fasn was significantly downregulated; the expression of the Sqle, Lss, and Irs2 genes between the C group and diabetic group treated with mulberry (DD) was significantly upregulated; the expression of Fabp2, Ly6a, and Grb10 was significantly downregulated; and the expression of Sqle and Lss was significantly upregulated in the DC and DD groups, but Tap1, Igf2, and Spns3 were significantly downregulated. The results of Western blot validation showed that dynamic changes in proteins, such as IGF2, Ly6a, Grb10, and UBD, occurred to regulate the incidence of diabetes by influencing the insulin receptor substrate (IRS) signaling pathway
The CDEX-1 1 kg Point-Contact Germanium Detector for Low Mass Dark Matter Searches
The CDEX Collaboration has been established for direct detection of light
dark matter particles, using ultra-low energy threshold p-type point-contact
germanium detectors, in China JinPing underground Laboratory (CJPL). The first
1 kg point-contact germanium detector with a sub-keV energy threshold has been
tested in a passive shielding system located in CJPL. The outputs from both the
point-contact p+ electrode and the outside n+ electrode make it possible to
scan the lower energy range of less than 1 keV and at the same time to detect
the higher energy range up to 3 MeV. The outputs from both p+ and n+ electrode
may also provide a more powerful method for signal discrimination for dark
matter experiment. Some key parameters, including energy resolution, dead time,
decay times of internal X-rays, and system stability, have been tested and
measured. The results show that the 1 kg point-contact germanium detector,
together with its shielding system and electronics, can run smoothly with good
performances. This detector system will be deployed for dark matter search
experiments.Comment: 6 pages, 8 figure
Sn nanoparticles on gas diffusion electrodes: Synthesis, characterization and use for continuous CO2 electroreduction to formate
Electrochemical reduction of CO2 has been pointed out as an interesting strategy to convert CO2 into useful chemicals. In addition, coupling CO2 electroreduction with renewable energies would allow storing electricity from intermittent renewable sources such as wind or solar power. In this work, an easy and fast method is adapted for the synthesis of pure and carbon supported Sn nanoparticles. The resulting nanoparticles have been characterized by transmission electron microscopy and their electrocatalytic properties towards CO2 reduction evaluated by cyclic voltammetry. Carbon supported Sn nanoparticles have been subsequently used to prepare Gas Diffusion Electrodes (Sn/C-GDEs). The electrodes have been characterized by scanning electron microscopy and also by cyclic voltammetry. Finally, the electrodes were tested on a continuous and single pass CO2 electroreduction filter-press type cell system in aqueous solution, to obtain formate at ambient pressure and temperature. These Sn/C-GDEs allow working at high current densities with low catholyte flow. Thus, for instance, at 150 mA cm−2, a 70% Faradaic Efficiency (FE) was obtained with a formate concentration of 2.5 g L−1. Interestingly, by increasing the current density to 200 mA cm−2 and decreasing the flow rate, a concentration over 16 g L−1 was reached. Despite the high concentrations obtained, further research is still required to keep high FE operating at high current densities.This work was conducted under the framework of the Spanish Ministry of Economy and Competitiveness projects CTQ2013-48280-C3-1-R and CTQ2013-48280-C3-3-R. Andrés Del Castillo also acknowledges the research grant from University of Cantabria, co-financed by the Regional Government of Cantabria
The impact of zeolite pore structure on the catalytic behavior of CuZnAl/zeolite hybrid catalysts for the direct DME synthesis
[EN] In this work, the influence of the pore structure of 10-ring zeolites used as the methanol dehydration func-tion in CuZnAl(CZA)/zeolite hybrid catalysts was studied for the direct dimethyl ether (DME) synthesis. Tothis purpose, six different 10-ring H-zeolites (ZSM-5, FER, IM-5, TNU-9, MCM-22, ITQ-2) with alike bulkSi/Al ratios (in the 9 14 range) were employed. Additionally, the effect of crystallite size (for ZSM-5) andselective surface dealumination by treatment with oxalic acid (for MCM-22) was also investigated. Whilethe initial activity of the zeolites for methanol dehydration was driven by the concentration of strongBrønsted acid sites, the extent of decay was dictated by the pore structure, which determined the amountand nature of the formed carbon species. When evaluated for direct DME synthesis under methanolsynthesis-controlled conditions, all CZA/zeolite hybrid catalysts (prepared by grinding, CZA:zeolite massratio of 2:1) experienced a decline of CO conversion (and DME yield) with time-on-stream (TOS) due toa gradual loss of the methanol synthesis activity of the Cu-based component. Interestingly, the stabilitywith TOS was the lowest for the hybrid catalysts comprising zeolites with large external surface areas(Sext) such as ITQ-2 and MCM-22. Moreover, for zeolites with similar Sext, the deactivation extent of thehybrid catalysts increased with the concentration of surface Al species (from XPS) in the zeolite. Thus,the delaminated ITQ-2 zeolite (Si/Alsurf= 10.6, Sext= 324 m2/g) produced the less stable hybrid while thatcomprising zeolite TNU-9 (Si/Alsurf= 17.9, Sext= 12 m2/g) displayed the highest stability during the syngas-to-DME experiments. These results suggest that the deterioration of the methanol synthesis activity ofthe CZA catalyst in the hybrid catalysts prepared by grinding is produced by detrimental interactionsbetween zeolitic Al species and Cu sites at the surface-contact between zeolite and CZA particleFinancial support by the Comision Interministerial de Ciencia y Tecnologia (CICYT) of Spain through the Project CTQ2010-17988/PPQ is gratefully acknowledged. A. Garcia-Trenco thanks the Ministerio de Economia y Competitividad (former Ministerio de Ciencia e Innovacion) of Spain for a predoctoral (FPI) scholarship.García Trenco, A.; Valencia Valencia, S.; Martinez Feliu, A. (2013). The impact of zeolite pore structure on the catalytic behavior of CuZnAl/zeolite hybrid catalysts for the direct DME synthesis. Applied Catalysis A General. 468:102-111. doi:10.1016/j.apcata.2013.08.038S10211146
Precision Measurement of the Mass of the Lepton
An energy scan near the pair production threshold has been performed
using the BESIII detector. About pb of data, distributed over four
scan points, was collected. This analysis is based on pair decays to
, , , , , , , and
final states, where denotes a charged or . The mass of the
lepton is measured from a maximum likelihood fit to the pair production
cross section data to be )
MeV/, which is currently the most precise value in a single measurement.Comment: 13 pages, 7 figure
Search for the radiative transitions and
By using a 2.92 fb data sample taken at GeV with
the BESIII detector operating at the BEPCII collider, we search for the
radiative transitions and
through the hadronic decays . No
significant excess of signal events above background is observed. We set upper
limits at a 90% confidence level for the product branching fractions to be
and
. Combining our result with world-average
values of , we find the
branching fractions
and at a 90%
confidence level.Comment: 10 pages, 4 figure
Search for C-parity violation in and
Using events recorded in
collisions at 3.686 GeV with the BESIII at the BEPCII collider, we
present searches for C-parity violation in and decays via . No significant
signals are observed in either channel. Upper limits on the branching fractions
are set to be and
at the 90\%
confidence level. The former is one order of magnitude more stringent than the
previous upper limit, and the latter represents the first limit on this decay
channel.Comment: 7 pages, 2 figure
Observation of at BESIII
Using events collected with the BESIII detector
at the BEPCII storage rings, we observe for the first time the process
,
with a significance of ( including systematic
uncertainties). The product branching fraction of is measured to be
, where the first error is statistical and the
second is systematic. This measurement provides information on the
production near threshold coupling to and improves the understanding
of the dynamics of decays to four body processes.Comment: 8 pages, 7 figure
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