To improve the response speed and control stability of power transformer coil temperature control, a fuzzy PID-based power transformer coil temperature control method is studied. Based on the physical model of power t...
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Thermal and mechanical properties of yttrium tantalate(YTaO_(4)),a top coat ceramic of thermal barrier coatings(TBCs)for aeroengines,are enhanced by synthesizing Y_(1-x)Ta_(1-x)M_(2x)O_(4)(M=Ti,Zr,Hf;x=0.06,0.12,0.18,...
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Thermal and mechanical properties of yttrium tantalate(YTaO_(4)),a top coat ceramic of thermal barrier coatings(TBCs)for aeroengines,are enhanced by synthesizing Y_(1-x)Ta_(1-x)M_(2x)O_(4)(M=Ti,Zr,Hf;x=0.06,0.12,0.18,0.24)medium-entropy ceramics(MECs)using a two-step sintering *** addition,the thermal conductivity,thermal expansion coefficients(TECs),and fracture toughness of MECs were *** X-ray diffraction study revealed that the Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs were monoclinic,and the Ti,Zr,and Hf doping elements replaced Y and *** variations in atomic weights and ionic radii led to disturbed atomic arrangements and severe lattice distortions,resulting in improving the phonon scattering and reduced thermal conductivity,with Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs(x=0.24)exhibiting the lowest thermal conductivity of 1.23 W·m^(-1)·K^(-1)at 900℃.The introduction of MO_(2) increased the configurational entropy and weakened the ionic bonding energy,obtaining high TECs(10.4×10^(-6)K^(-1)at 1400℃).The reduction in the monoclinic angle β lowered the ferroelastic domain inversion energy ***,microcracks and crack extension toughening endowed Y_(1-x)Ta_(1-x)M_(2x)O_(4) MECs(x=0.24)with the highest fracture toughness of(4.1±0.5)MPa·m~(1/2).The simultaneous improvement of the thermal and mechanical properties of the MO_(2)(M=Ti,Zr,Hf)co-doped YTaO_(4) MECs can be extended to other materials.
Nowadays, the Underwater Remotely Operated Vehicle (ROV) has captivated the interest of researchers, given its widespread applications in both military and marine industries. However, establishing a standardized model...
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Nowadays, the Underwater Remotely Operated Vehicle (ROV) has captivated the interest of researchers, given its widespread applications in both military and marine industries. However, establishing a standardized model for use in challenging conditions, such as the presence of added mass, poses a significant challenge. The ROV serves a crucial role in oceanographic research, contributing to data collection, image recording, and deep-sea surveys. The development of a standard model holds promise for enabling researchers to design ROVs suitable for diverse tasks across varying ocean depths. In this study, for the first time, propose a natural frequency analysis of an ROV, considering added mass. Additionally, conduct a strength analysis for the ROV under critical boundary conditions, including displacement in a dry environment and Stuck in the sludge of the sea. The natural frequency analysis of the underwater environment, considering the acoustic properties of water fluid, is performed using ABAQUS software. The natural frequency of an object in water, indicating the frequency of vibrations per second, depends on factors such as temperature, pressure, and density of the surrounding water. This analysis, integral to structural dynamics, provides valuable insights into how vibrations propagate, facilitating the design of more stable structures. Furthermore, the study investigates the effects of added mass on different vibration modes of the ROV in the MATLAB Environment. Stress analysis results demonstrate that the ROV, submerged in critical boundary conditions due to hydrostatic forces, drag, and equipment weight, possesses sufficient strength for movement in deep-sea environments. Natural frequency analysis in water reveals a reduction in the impact of surrounding fluid and added mass in high-frequency modes. To enhance evaluations of fluid dynamics around the structure, fluid dimensions are considered until the structure’s frequency and resulting frequencies converge
Different types of lead-free solder alloys were obtained by processing them in an electric induction furnace and gravity casting. The effects of adding Sn, Ag and Sb on the microstructure, melting behavior and mechani...
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Solar flares are one of the strongest outbursts of solar activity,posing a serious threat to Earth’s critical infrastructure,such as communications,navigation,power,and ***,it is essential to accurately predict solar...
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Solar flares are one of the strongest outbursts of solar activity,posing a serious threat to Earth’s critical infrastructure,such as communications,navigation,power,and ***,it is essential to accurately predict solar flares in order to ensure the safety of human ***,the research focuses on two directions:first,identifying predictors with more physical information and higher prediction accuracy,and second,building flare prediction models that can effectively handle complex observational *** terms of flare observability and predictability,this paper analyses multiple dimensions of solar flare observability and evaluates the potential of observational parameters in *** flare prediction models,the paper focuses on data-driven models and physical models,with an emphasis on the advantages of deep learning techniques in dealing with complex and high-dimensional *** reviewing existing traditional machine learning,deep learning,and fusion methods,the key roles of these techniques in improving prediction accuracy and efficiency are *** prevailing challenges,this study discusses the main challenges currently faced in solar flare prediction,such as the complexity of flare samples,the multimodality of observational data,and the interpretability of *** conclusion summarizes these findings and proposes future research directions and potential technology advancement.
The solid–liquid interface energy anisotropy of Zn alloys remains poorly understood. Recently, characteristic 14-arm dendritic growth has been observed using time-resolved X-ray computed tomography at SPring-8 during...
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An electrocardiogram (ECG) measures the electrical activity of the heart. It is valuable for the early detection of cardiovascular disease (CVD). Advancements in medical diagnosis using artificial intelligence have po...
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Rapid advancements in automated vehicles(AVs)technology have transformed the measurability,controllability and unpredictability of transportation *** driving risk and effectively managing driving behaviours is *** sho...
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Rapid advancements in automated vehicles(AVs)technology have transformed the measurability,controllability and unpredictability of transportation *** driving risk and effectively managing driving behaviours is *** should be enabled to identify,analyse,evaluate and devise effective countermeasures for driving risk by autonomously learning from human driving *** learning will enhance the interactive decision-making capabilities and achieve driving behaviours that reflect human-like *** primary challenge lies in integrating human-like logic and driving risk constraints based on behavioural decision-making *** integration is crucial to align the AVs’cognitive levels-movement,comprehension,memory and inference-more closely with human driving necessities,habits and *** alignment holds the potential to improve the prediction and planning of future actions and facilitate the development of motion planning schemes geared towards minimizing driving *** performed a comprehensive review of AVs’behavioural decision-making and intelligent motion-planning research from 2000 to 2023 from four key perspectives-driving risk,human-like logic,behavioural decision making and motion *** on the Web of science and China National Knowledge Internet database,the results of our review indicate that significant progress has been made in AV behavioural decision making and intelligent motion planning over *** AVs and human-driven vehicles coexist,greater incorporation of human-like logic is *** by these findings,we delineate future development directions and propose a research paradigm for human-like logic and a research framework for human-like logic-driven behavioural decision making and intelligent motion planning of AVs.
Thermal barrier coatings(TBCs) materials with lowered the rmal and oxygen ion conductivity can provide thermal and oxidative protection for high te mperature hot-end components in aero nautical engines and gas turbine...
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Thermal barrier coatings(TBCs) materials with lowered the rmal and oxygen ion conductivity can provide thermal and oxidative protection for high te mperature hot-end components in aero nautical engines and gas turbines,The rare-earth tantalate RETaO_(4)(RE=Dy,Gd and Sm) ceramics with monoclinic(m) phase were successfully synthesized via spark plasma *** vacancies responsible for the thermal and oxygen ion conductivities of RETaO_(4) were demonstrated by atomic-resolution energy dispersive Xray and X-ray photoelectron *** the three samples,DyTaO_(4) has excellent oxygen/thermal barrier *** to the current service thermal barrier coating material ZrO_(2)-8 wt% Y_(2)O_(3)(8 YSZ),DyTaO_(4) has an ultra-low oxygen ion conductivity benefiting from low oxygen vacancy concentration and strong stretching force *** intrinsic thermal conductivity of DyTaO_(4)is 68.2% less than that of 8 ***,the thermal expansion rate curves indicate that the phase transformation does not happen from room te mperature to 1200℃.The above results demonstrate that high-growth rate the rmally grown oxide can be retarded by creating dense DyTaO_(4) coating with lowered thermal and oxygen ion conductivity.
In this work, VoteDroid a novel fine-tuned deep learning models-based ensemble voting classifier has been proposed for detecting malicious behavior in Android applications. To this end, we proposed adopting the random...
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