Aiming at the problems of low detection efficiency and difficult positioning of traditional steel surface defect detection methods, a lightweight steel surface defect detection model based on you only look once versio...
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Aiming at the problems of low detection efficiency and difficult positioning of traditional steel surface defect detection methods, a lightweight steel surface defect detection model based on you only look once version 7(YOLOv7) is proposed. First, a cascading style sheets(CSS) block module is proposed, which uses more lightweight operations to obtain redundant information in the feature map, reduces the amount of computation, and effectively improves the detection speed. Secondly, the improved spatial pyramid pooling with cross stage partial convolutions(SPPCSPC) structure is adopted to ensure that the model can also pay attention to the defect location information while predicting the defect category information, obtain richer defect features. In addition, the convolution operation in the original model is simplified, which significantly reduces the size of the model and helps to improve the detection speed. Finally, using efficient intersection over union(EIOU) loss to focus on high-quality anchors, speed up convergence and improve positioning accuracy. Experiments were carried out on the Northeastern University-defect(NEU-DET) steel surface defect dataset. Compared with the original YOLOv7 model, the number of parameters of this model was reduced by 40%, the frames per second(FPS) reached 112, and the average accuracy reached 79.1%, the detection accuracy and speed have been improved, which can meet the needs of steel surface defect detection.
Precise monitoring of the microfluidic flow rate is a key factor in microfluidic chips. However, the temperature of the microfluidics often affects the measuring results of the optical flow rate sensor. Here, we prese...
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Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored ...
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Turbulent agglomeration is viewed as a promising technology for enhancing fine particle removal *** better understand particle transport,agglomeration behaviors,and fluid-particle interactions,we numerically explored these phenomena under cylindrical vortex wake influence using a coupled large eddy simulation and discrete element method(LES-DEM)*** validity of the LES approach was verified by comparison with available direct numerical simulation(DNS)*** adopted the Johnson-Kendall-Roberts(JKR)contact model for particle-particle *** particle dispersion and agglomeration characteristics of particles with different diameters(d_(p)=2-20μm)in the laminar and transition of shear layer(TrSL)flow regimes were *** particles were concentrated at the vortex centers,while larger particles accumulated around the *** agglomeration efficiency exhibited an M-shaped profile spanwise(y-direction).With increasing Reynolds number,the agglomeration efficiency and turbulence intensity *** particle agglomeration efficiency peaks at a certain Reynolds ***,at higher Reynolds numbers,reducing the residence time of particles in the flow field decreases the agglomeration efficiency.
To enhance the electrochemical performance of the reversible solid oxide cell(RSOC),a facile way through adopting A-site deficient Pr_(0.94)PrBaCo_(1.5)Fe_(0.5)O_(5+δ)(PBCF94)as an air electrode for RSOC is *** desig...
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To enhance the electrochemical performance of the reversible solid oxide cell(RSOC),a facile way through adopting A-site deficient Pr_(0.94)PrBaCo_(1.5)Fe_(0.5)O_(5+δ)(PBCF94)as an air electrode for RSOC is *** designed A-site Pr-deficient air electrode is expected to provide abundant oxygen vacancies,macroscopic nanoparticle generation,excellent redox properties and oxygen mobility,which ultimately contribute to the enhanced electrocatalytic *** results confirm that the RSOC with an A-site deficient air electrode exhibits considerable peak power density up to 1.53 W·cm^(-2),and the desirable electrolysis current density reaches 2.29 A·cm^(-2)at 1.5 V and 800℃.Correspondingly,the RSOC exhibits remarkable long-term reversible stability of 200 ***,the A-site deficient Pr_(0.94)PrBaCo_(1.5)Fe_(0.5)O_(5+δ)air electrode could be the potential one for RSOC application.
Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading *** and TEM results showed that Cu and Mn were successfully co-doped into CeO_(2) without f...
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Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading *** and TEM results showed that Cu and Mn were successfully co-doped into CeO_(2) without forming heterostructure,XPS and photoelectrochemical results revealed that Mn ions doping amplified the generation of photo-induced charge carriers,while Cu ions doping significantly facilitated the interfacial charge transfer ***,the optimized Cu3Mn2CeO_(2) nanoparticles exhibited the highest TC removal efficiency,achieved a rate of 78.18%and maintained a stable cycling performance.
It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield *** paper provides a comprehensiv...
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It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield *** paper provides a comprehensive overview of advances in the development of bumper materials for spacecraft shield *** particular,the protective mechanism and process of the bumper using different materials against hypervelocity impact are reviewed and *** advantages and disadvantages of each material used in shield were discussed,and the performance under hypervelocity impact was given according to the specific *** review provides the useful reference and basis for researchers and engineers to create bumper materials for spacecraft shield applications,and the contemporary challenges and future directions for bumper materials for spacecraft shield were presented.
High thermal conductivity and high strength Mg-1.5Mn-2.5Ce alloy with a tensile yield strength of 387.0 MPa,ultimate tensile strength of 395.8 MPa,and thermal conductivity of 142.1 W/(m·K)was successfully fabrica...
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High thermal conductivity and high strength Mg-1.5Mn-2.5Ce alloy with a tensile yield strength of 387.0 MPa,ultimate tensile strength of 395.8 MPa,and thermal conductivity of 142.1 W/(m·K)was successfully fabricated via hot *** effects of La and Ce additions on the microstructure,thermal conductivity,and mechanical properties of the Mg-1.5Mn alloy were *** results indicated that both the as-extruded Mg-1.5Mn-2.5La and Mg-1.5Mn-2.5Ce alloys exhibited a bimodal grain structure,with dynamically precipitated nano-scaleα-Mn *** comparison with La,the addition of Ce enhanced the dynamic precipitation more effectively during hot extrusion,while its influence on promoting the dynamic recrystallization was relatively *** high tensile strength obtained in the as-extruded Mg-1.5Mn-2.5RE alloys can be attributed to the combined influence of the bimodal grain structure(with fine dynamic recrystallized(DRXed)grain size and high proportion of un-dynamic recrystallized(unDRXed)grains),dense nano-scale precipitates,and broken Mg12RE phases,while the remarkable thermal conductivity was due to the precipitation of Mn-rich phases from the Mg matrix.
Researchers have recently achieved significant advances in deep learning techniques, which in turn has substantially advanced other research disciplines, such as natural language processing, image processing, speech r...
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Researchers have recently achieved significant advances in deep learning techniques, which in turn has substantially advanced other research disciplines, such as natural language processing, image processing, speech recognition, and software engineering. Various deep learning techniques have been successfully employed to facilitate software engineering tasks, including code generation, software refactoring, and fault localization. Many studies have also been presented in top conferences and journals, demonstrating the applications of deep learning techniques in resolving various software engineering tasks. However,although several surveys have provided overall pictures of the application of deep learning techniques in software engineering,they focus more on learning techniques, that is, what kind of deep learning techniques are employed and how deep models are trained or fine-tuned for software engineering tasks. We still lack surveys explaining the advances of subareas in software engineering driven by deep learning techniques, as well as challenges and opportunities in each subarea. To this end, in this study, we present the first task-oriented survey on deep learning-based software engineering. It covers twelve major software engineering subareas significantly impacted by deep learning techniques. Such subareas spread out through the whole lifecycle of software development and maintenance, including requirements engineering, software development, testing, maintenance, and developer collaboration. As we believe that deep learning may provide an opportunity to revolutionize the whole discipline of software engineering, providing one survey covering as many subareas as possible in software engineering can help future research push forward the frontier of deep learning-based software engineering more systematically. For each of the selected subareas,we highlight the major advances achieved by applying deep learning techniques with pointers to the available datasets i
The fatigue life of components can be significantly enhanced by the formation of the surface hardness layer through surface strengthening *** avoid the geometric distortion of thin-walled com-ponents caused by strengt...
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The fatigue life of components can be significantly enhanced by the formation of the surface hardness layer through surface strengthening *** avoid the geometric distortion of thin-walled com-ponents caused by strengthening,the strengthening energy is limited and the ideal strengthening effect cannot be *** work aims to propose a novel approach to address this issue *** surface layer with high-density dislocations was obtained by a low-energy surface strengthening method(shot peening)at *** the surface strengthening mechanism changes from dislocation strengthen-ing to grain boundary strengthening after electropulsing treatment(EPT).The evolution of residual stress and microstructure was analyzed using multi-scale characterization *** results demonstrate that EPT followed by surface strengthening makes a remarkable 304%increase in fatigue life of TC11 titanium *** enhancement of fatigue life can be attributed to the grain refinement accompanied by the formation of nanotwins and sub-grains in the surface-strengthened layer,as well as the reduction in dislocation density within the substrate after *** study demonstrates the significant potential of EPT in further enhancing the fatigue life of surface pre-strengthened thin-walled components.
Poly(1,3-dioxolane)(PDOL)-based solid electrolytes hold great potential for solid-state lithium(Li)metal batteries due to their superior ionic conductivity at room ***,traditional PDOL electrolytes suffer from inferio...
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Poly(1,3-dioxolane)(PDOL)-based solid electrolytes hold great potential for solid-state lithium(Li)metal batteries due to their superior ionic conductivity at room ***,traditional PDOL electrolytes suffer from inferior thermal stability,which has hampered their practical *** this work,a competitive coordination mechanism is proposed to strengthen vulnerable ether oxygen bonds in PDOL chains,thereby improving the thermal stability of PDOL *** strong coordination of Lewis base ligands on Li_(6.75)La_(3)Zr_(1.75)Ta_(0.25)O_(12)(LLZTO)surface with Li ions weakens the ionic-dipolar interactions between PDOL chains and Li ions,conversely reinforcing the bond energy of ether oxygen *** LLZTO into PDOL electrolytes effectively enhances the thermal decomposition temperature from 110 to 302℃.Li||LiFePO_(4)full cell with a 12μm ultrathin PDOL hybrid electrolyte delivers enhanced discharge capacity and extended cycling life for 100 cycles at an elevated temperature of 60℃.This work provides critical insights into the development of thermally stable PDOL electrolytes for safe solid-state Li metal batteries.
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