Dear Editor,This letter studies the bipartite consensus tracking problem for heterogeneous multi-agent systems with actuator faults and a leader's unknown time-varying control input. To handle such a problem, the ...
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Dear Editor,This letter studies the bipartite consensus tracking problem for heterogeneous multi-agent systems with actuator faults and a leader's unknown time-varying control input. To handle such a problem, the continuous fault-tolerant control protocol via observer design is developed. In addition, it is strictly proved that the multi-agent system driven by the designed controllers can still achieve bipartite consensus tracking after faults occur.
The sampling process is very inefficient for sam-pling-based motion planning algorithms that excess random sam-ples are generated in the planning *** this paper,we pro-pose an adaptive space expansion(ASE)approach whi...
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The sampling process is very inefficient for sam-pling-based motion planning algorithms that excess random sam-ples are generated in the planning *** this paper,we pro-pose an adaptive space expansion(ASE)approach which belongs to the informed sampling category to improve the sampling effi-ciency for quickly finding a feasible *** ASE method enlarges the search space gradually and restrains the sampling process in a sequence of small hyper-ellipsoid ring subsets to avoid exploring the unnecessary ***,for a con-structed small hyper-ellipsoid ring subset,if the algorithm cannot find a feasible path in it,then the subset is ***,the ASE method successively does space exploring and space expan-sion until the final path has been ***,we present a particular construction method of the hyper-ellipsoid ring that uniform random samples can be directly generated in *** last,we present a feasible motion planner BiASE and an asymptoti-cally optimal motion planner BiASE*using the bidirectional exploring method and the ASE *** demon-strate that the computation speed is much faster than that of the state-of-the-art *** source codes are available at https://***/shshlei/ompl.
A quantitative relationship between grain size and Young's modulus of metal composites has not been established by considering the coupling effect of the reinforcements on microstructural *** objective of this stu...
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A quantitative relationship between grain size and Young's modulus of metal composites has not been established by considering the coupling effect of the reinforcements on microstructural *** objective of this study is to investigate the mechanism of deformation coordination between the carbon nanotube and the composite microstructure using molecular dynamics *** the analysis of stress contributions from grain boundaries and grains,a grain size-dependent continuum model for the pure metal modulus is *** this basis,a predictive model for the modulus of metallic composites is developed by considering the coupling deformation between carbon nanotubes and the *** proposed model is capable of accurately capturing the relationship between grain size and the modulus of metal *** study provides a guideline for microstructure-dependent multiscale modeling.
The reduced-activation ferritic/martensitic(RAFM)steel CLF-1 has been designed as a candidate structural material for nuclear fusion energy *** engineering mechanical design,the effects of temperature on the strain di...
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The reduced-activation ferritic/martensitic(RAFM)steel CLF-1 has been designed as a candidate structural material for nuclear fusion energy *** engineering mechanical design,the effects of temperature on the strain distribution of CLF-1 steel during uniaxial tensile tests were explored within the temperature range from room temperature to 650°C using uniaxial tensile tests combined with in situ digital image correlation ***-concentrated regions alternately distributed±45°along the tensile direction could be attributed to the shear stress having the maximum value at±45°along the tensile direction and the coordinated deformation of the *** total strain distribution changed from a normal distribution to a lognormal distribution with increasing deformation owing to the competition between the elastic and plastic strains at all test *** localization has a strong relationship with temperature at the same engineering strain because of the temperature effects on dynamic strain aging(DSA).The stronger the DSA effect,the stronger the strain *** increasing temperature,the stronger the strain localization at the same strain,the weaker the plasticity,that is,DSA-induced embrittlement,and the slower the strength decline,that is,DSA-induced hardening.
With the rise of probiotics fermentation in food industry,fermented foods have attracted worldwide *** this study,protective effects of Rosa roxburghii&edible fungus fermentation broth(REFB)on immune function and ...
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With the rise of probiotics fermentation in food industry,fermented foods have attracted worldwide *** this study,protective effects of Rosa roxburghii&edible fungus fermentation broth(REFB)on immune function and gut health in Cyclophosphamide induced immunosuppressed mice were *** showed that REFB could improve the immune organ index,and promote the proliferation and differentiation of splenic T *** addition,it attenuated intestinal mucosal damage and improved intestinal cellular *** administration also up-regulated the expression of IL-4,INF-γ,TNF-α,T-bet and GATA-3 mRNA in small ***,administration of REFB modulated gut microbiota composition and increased the relative abundance of beneficial genus,such as *** also increased the production of fecal short-chain fatty *** indicate that REFB has the potential to improve immunity,alleviate intestinal injury and regulate gut microbiota in immunosuppressed mice.
Wheat is the most widely grown crop in the world,and its yield is closely related to global food *** number of ears is important for wheat breeding and yield ***,automated wheat ear counting techniques are essential f...
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Wheat is the most widely grown crop in the world,and its yield is closely related to global food *** number of ears is important for wheat breeding and yield ***,automated wheat ear counting techniques are essential for breeding high-yield varieties and increasing grain ***,all existing methods require position-level annotation for training,implying that a large amount of labor is required for annotation,limiting the application and development of deep learning technology in the agricultural *** address this problem,we propose a count-supervised multiscale perceptive wheat counting network(CSNet,count-supervised network),which aims to achieve accurate counting of wheat ears using quantity *** particular,in the absence of location information,CSNet adopts MLP-Mixer to construct a multiscale perception module with a global receptive field that implements the learning of small target attention maps between wheat ear *** conduct comparative experiments on a publicly available global wheat head detection dataset,showing that the proposed count-supervised strategy outperforms existing position-supervised methods in terms of mean absolute error(MAE)and root mean square error(RMSE).This superior performance indicates that the proposed approach has a positive impact on improving ear counts and reducing labeling costs,demonstrating its great potential for agricultural counting *** code is available at .
When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ...
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When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of *** address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent *** leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration *** analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,*** model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target *** maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed ***,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves.
In order to mitigate the harm of alumina,calcium aluminate,and magnesium aluminum spinel inclusions on the fatigue performance of bearing steel,the effect of Ce-Mg composite treatment on the cleanliness of silicon-kil...
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In order to mitigate the harm of alumina,calcium aluminate,and magnesium aluminum spinel inclusions on the fatigue performance of bearing steel,the effect of Ce-Mg composite treatment on the cleanliness of silicon-killed GCr15 bearing steel and the evolution of Ce-Mg-Mn-O-S composite inclusions during heat treatment of the steels at 1523 K were investigated in this present *** results indicate that the cleanliness of S2 with 0.0045 wt%Ce and 0.0016 wt%Mg is better than that in S1 with0.0020 wt%Ce and 0.0011 wt%Mg,which is attributed to the more effective removal of Ce-Mg-Mn-O-S composite inclusions,with help of good aggregation capacity of Ce-containing inclusions and small volume density of Mg-containing inclusions,due to the increase of rare earth and magnesium *** aspect ratio and area fraction of the Ce-Mg-Mn-O-S composite inclusions in as-cast steel decrease significantly with isothermal treatment at 1523 K for 150 min,due to the effect of(ⅰ)Ostwald aging mechanism of inclusions and(ⅱ)sulfide solid solution during isothermal *** the increase of isothermal treatment time from 150 to 550 min,the aspect ratio and area fraction of the inclusions in SO(untreated steel)and S1 decrease slightly,because spheroidization and solid solution of inclusions reach their basic equilibrium at 1523 ***,the aspect ratio and area fraction of the Ce-Mg-Mn-O-S composite inclusions in S2 actually increase,and the inclusions evolve into three-phase(two-phase)inclusions,which is attributed to(ⅲ)transformation of phase compositions in inclusions and interfacial reaction between inclusions and steel matrix during isothermal ***,the control of inclusions in silicon-killed bearing steel with Ce and Mg composite treatment should be combined with specific heat treatment processes and appropriate rare earth and magnesium contents,to minimize the damage of inclusions on the fatigue performance of bearing steel products.
Doping of rare earth elements into Bi_(4)Ti_(3)O_(12) can significantly enhance the upconversion photoluminescence(UCPL)properties,but its structure-property relationship is still *** this work,Er-doped bismuth titana...
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Doping of rare earth elements into Bi_(4)Ti_(3)O_(12) can significantly enhance the upconversion photoluminescence(UCPL)properties,but its structure-property relationship is still *** this work,Er-doped bismuth titanate Bi_(4-x)Er_(x)Ti_(3)O_(12)(x=0,0.1,0.2,0.3,0.4,0.5)ceramics were synthesized via solid-state reaction *** x-ray diffraction analysis confirmed the orthorhombic crystalline structure of the Bi4-xErxTi_(3)O_(12) ceramics without any secondary *** and calculations of positron annihilation spectroscopy were carried out to characterize their defect *** comparison between the experimental and calculated lifetime revealed that vacancy clusters were the main defects in the *** increase of the intensity of the second positron lifetime component(I_(2))of Bi_(3.5)Er_(0.5)Ti_(3)O_(12)ceramics indicated the presence of a high concentration of vacancy *** UCPL spectra showed the sudden enhanced UCPL performance in Bi3.7Er0.3Ti3O12and Bi_(3.5)Er_(0.5)Ti_(3)O_(12)ceramics,which were consistent with the variation of the second positron lifetime component(I2).These results indicate that the enhanced UCPL properties are influenced not only by the concentrations of rare earth ions but also by the concentration of vacancy clusters present within the ceramics.
The evolution of Ce-containing inclusions and its correlation with the reoxidation of liquid steel during protective atmosphere electroslag remelting(ESR)of heat-resistant steel were *** reoxidation of liquid steel to...
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The evolution of Ce-containing inclusions and its correlation with the reoxidation of liquid steel during protective atmosphere electroslag remelting(ESR)of heat-resistant steel were *** reoxidation of liquid steel took place during the ESR,resulting in the oxygen pickup from 0.0014 to 0.0053 wt.%.The inclusions in the consumable electrode,liquid metal pool and remelted ingot are Ce_(2)O_(2)S and Ce_(2)O,inclusions *** inclusions in the remelted ingot are originated from three ways:(I)the original inclusions from the electrode;(Il)the newly formed Ce_(2)O_(2)S and Ce_(2)O_(3) inclusions in the liquid metal pool by reoxidation remaining still in remelted ingot;(IlI)the newly generated Ce2O2S and Ce_(2)O_(3) inclusions during cooling and solidification of liquid *** relative proportions of Ce_(2)O_(3) inclusions in liquid metal pool and remelted ingot are 41% and 76.5%,*** inclusions ranging from 2 to 5μm in the remelted ingot take up 55%,followed by the inclusions smaller than 2μm(43%of total inclusions).The number proportion of the Ce_(2)0,inclusions in the liquid metal pool which were removed by floating up into slag is 1.96×10-5%.
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