Osteochondral defect caused by trauma or osteoarthritis exhibits a major challenge in clinical treatment with limited symptomatic effects at *** regeneration and remodeling of subchondral bone play a positive effect o...
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Osteochondral defect caused by trauma or osteoarthritis exhibits a major challenge in clinical treatment with limited symptomatic effects at *** regeneration and remodeling of subchondral bone play a positive effect on cartilage regeneration and further promotes the repair of osteochondral *** use of the strengths of each preparation method,the combination of 3D printing and electrospinning is a promising method for designing and constructing multi-scale scaffolds that mimic the complexity and hierarchical structure of subchondral bone at the microscale and nanoscale,*** this study,the 3D printed-electrospun poly(ɛ-caprolactone)/nano-hydroxyapatites/multi-walled carbon nanotubes(PCL/nHA/MWCNTs)scaffolds were successfully constructed by the combination of electrospinning and layer-by-layer 3D *** resulting dual-scale scaffold consisted of a dense layer of disordered nanospun fibers and a porous microscale 3D scaffold layer to support and promote the ingrowth of subchondral ***,the biomimetic PCL/nHA/MWCNTs scaffolds enhanced cell seeding efficiency and allowed for higher cell-cell interactions that supported the adhesion,proliferation,activity,morphology and subsequently improved the osteogenic differentiation of bone marrow mesenchymal stem cells in ***,this study elucidates that the construction of 3D printed-electrospun PCL/nHA/MWCNTs scaffolds provides an alternative strategy for the regeneration of subchondral bone and lays a foundation for subsequent in vivo studies.
Load prediction is the foundation of power system operation and analysis. It also plays a decisive role in the safety, stability, and economic operation of the smart grid. Traditional load forecasting methods are too ...
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This paper presents a rapid autonomous navigation technology for Earth satellites using static infrared Earth sensor (SIES). Conventional Earth sensor has limitations in target and background segmentation, geocentric ...
This paper presents a rapid autonomous navigation technology for Earth satellites using static infrared Earth sensor (SIES). Conventional Earth sensor has limitations in target and background segmentation, geocentric vector direction extraction, and interference rejection. A novel SIES sensor design is proposed that incorporates new technologies to increase light transmittance, reduce circuit noise, and improve image processing and attitude determination algorithms. This enables higher angular accuracy and new geocentric distance measurement information, resulting in significantly improved satellite attitude measurement accuracy of ±0. 01 °. The rapid autonomous navigation system framework for Geosynchronous (GEO) satellites using novel geocentric measurements by SIES is presented, including observability analysis, accuracy metrics acquisition, and autonomous navigation information fusion algorithms. This technology has been successfully verified on China's new generation of geosynchronous orbit satellite platform, as well as other Earth-centered orbit types.
RGB-thermal semantic segmentation is a potential solution for reliable semantic scene understanding under adverse weather and complex lighting conditions. However, past studies have primarily focused on the design of ...
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In this paper, the design and measurement of a mode-suppression circuit (MSC) applied in the nonlinear interaction region of a Ka-band gyrotron travelling wave tube (gyro-TWT) are presented. The proposed MSC is capabl...
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The prediction of the remaining useful life of the turbofan engine of an aircraft is a very important part of its PHM. With the arrival of the era of Big data, data driven RUL prediction methods are gradually emerging...
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In this paper, a fault diagnosis method based on Collaborative Residual Network (Collaborative ResNet) is proposed to address the problem of imbalanced fault diagnosis for key components of spacecraft attitude control...
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In this paper,a new guidance law based on deep reinforcement learning is proposed for the high-speed maneuvering target attack ***,the missile-target kinematic model is established,and the action space and state space...
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ISBN:
(数字)9789887581536
ISBN:
(纸本)9781665482561
In this paper,a new guidance law based on deep reinforcement learning is proposed for the high-speed maneuvering target attack ***,the missile-target kinematic model is established,and the action space and state space of reinforcement learning are ***,according to the missile strike process,the reward function suitable for this scenario is *** proximal policy optimization(PPO) based guidance law construction is ***,the strike effect in multiple sets of experiments verifies the effectiveness of the method proposed in this paper.
WE are in an exciting new intelligent era where various Web 3.0 systems emerge and flourish.[1]–[3].In this new epoch,the collaboration of data and knowledge,humans and machines,actual and virtual worlds is undergoin...
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WE are in an exciting new intelligent era where various Web 3.0 systems emerge and flourish.[1]–[3].In this new epoch,the collaboration of data and knowledge,humans and machines,actual and virtual worlds is undergoing an unprecedented diversification and community-driven transformation,unveiling an open future full of boundless ***,the value of dispersed data extends far beyond passive storage and application.
Global Navigation Satellite system(GNSS) is initially designed to provide services to objects on the earth surfaces, or in the earth-orbits with altitude below 3000 km. However, previous researches show that GNSS rece...
Global Navigation Satellite system(GNSS) is initially designed to provide services to objects on the earth surfaces, or in the earth-orbits with altitude below 3000 km. However, previous researches show that GNSS receivers mounted on GEO satellites can receive GNSS signals and generate positioning and navigation results as well. Considering that in some harsh situations, such as bad observation geometry, weak signal acquisition, etc., the on-board GNSS receivers can only transfer pseudo-range data to GEO satellites, this paper proposed an autonomous navigation method in which the information from GNSS receiver, optical attitude sensors, and inter-satellite links are fused together: at first, the extended state equation and measurement equation of a GEO satellite with optical sensor's errors are deduced;then, an extended Kalman filter is designed to evaluate and compensate optical sensor's errors via constructed earthcentered vector bias;later, a sequential correction is carried out using intersatellite link measurements;finally, the performance of proposed method is analyzed through Monte-Carlo simulation. It shows that the average distance and velocity evaluation errors of proposed method are around 0.2 Km and 0.05 m/s individually;the performance can meet the requirements of survivability of a class of high-orbit, long-life and high-value satellites.
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