Nonleaching Bacteria-Responsive Antibacterial Surface Based on a Unique Hierarchical Architecture

The use of porous three-dimensional (3D) composite scaffolds has attracted great attention in bone tissue engineering applications because they closely simulate the major features of the natural extracellular matrix (ECM) of bone. This study aimed to prepare biomimetic composite scaffolds via a simple 3D printing of gelatin/hyaluronic acid (HA)/hydroxyapatite (HAp) and subsequent biomineralization for improved bone tissue regeneration. The resulting scaffolds exhibited uniform structure and homogeneous pore distribution. In addition, the microstructures of the composite scaffolds showed an ECM-mimetic structure with a wrinkled internal surface and a porous hierarchical architecture. The results of bioactivity assays proved that the morphological characteristics and biomineralization of the composite scaffolds influenced cell proliferation and osteogenic differentiation. In particular, the biomineralized gelatin/HA/HAp composite scaffolds with double-layer staggered orthogonal (GEHA20-ZZS) and double-layer alternative structure (GEHA20-45S) showed higher bioactivity than other scaffolds. According to these results, biomineralization has a great influence on the biological activity of cells. Hence, the biomineralized composite scaffolds can be used as new bone scaffolds in bone regeneration.

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A Hierarchical Architecture of Functionalized Polyaniline/Manganese Dioxide Composite with Stable-Enhanced Electrochemical Performance

Journal of Composites Science ◽

10.3390/jcs5050129 ◽

2021 ◽

Vol 5 (5) ◽

pp. 129

Author(s):

Yapeng Wang ◽

Yanxiang Wang ◽

Chengjuan Wang ◽

Yongbo Wang

Keyword(s):

Electrochemical Performance ◽

Manganese Dioxide ◽

Specific Capacitance ◽

Current Density ◽

Electrode Materials ◽

High Efficiency ◽

Scanning Speed ◽

Hierarchical Architecture ◽

Electrochemical Window ◽

A Current

As one of the most outstanding high-efficiency and environmentally friendly energy storage devices, the supercapacitor has received extensive attention across the world. As a member of transition metal oxides widely used in electrode materials, manganese dioxide (MnO2) has a huge development potential due to its excellent theoretical capacitance value and large electrochemical window. In this paper, MnO2 was prepared at different temperatures by a liquid phase precipitation method, and polyaniline/manganese dioxide (PANI/MnO2) composite materials were further prepared in a MnO2 suspension. MnO2 and PANI/MnO2 synthesized at a temperature of 40 °C exhibit the best electrochemical performance. The specific capacitance of the sample MnO2-40 is 254.9 F/g at a scanning speed of 5 mV/s and the specific capacitance is 241.6 F/g at a current density of 1 A/g. The specific capacitance value of the sample PANI/MnO2-40 is 323.7 F/g at a scanning speed of 5 mV/s, and the specific capacitance is 291.7 F/g at a current density of 1 A/g, and both of them are higher than the specific capacitance value of MnO2. This is because the δ-MnO2 synthesized at 40 °C has a layered structure, which has a large specific surface area and can accommodate enough electrolyte ions to participate the electrochemical reaction, thus providing sufficient specific capacitance.

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End-to-End Autonomous Driving Through Dueling Double Deep Q-Network

Automotive Innovation ◽

10.1007/s42154-021-00151-3 ◽

2021 ◽

Author(s):

Baiyu Peng ◽

Qi Sun ◽

Shengbo Eben Li ◽

Dongsuk Kum ◽

Yuming Yin ◽

...

Keyword(s):

Neural Network ◽

State Space ◽

Learning Algorithm ◽

Rapid Development ◽

Autonomous Driving ◽

Saliency Map ◽

Hierarchical Architecture ◽

Link Type ◽

The Neural Network ◽

End To End

AbstractRecent years have seen the rapid development of autonomous driving systems, which are typically designed in a hierarchical architecture or an end-to-end architecture. The hierarchical architecture is always complicated and hard to design, while the end-to-end architecture is more promising due to its simple structure. This paper puts forward an end-to-end autonomous driving method through a deep reinforcement learning algorithm Dueling Double Deep Q-Network, making it possible for the vehicle to learn end-to-end driving by itself. This paper firstly proposes an architecture for the end-to-end lane-keeping task. Unlike the traditional image-only state space, the presented state space is composed of both camera images and vehicle motion information. Then corresponding dueling neural network structure is introduced, which reduces the variance and improves sampling efficiency. Thirdly, the proposed method is applied to The Open Racing Car Simulator (TORCS) to demonstrate its great performance, where it surpasses human drivers. Finally, the saliency map of the neural network is visualized, which indicates the trained network drives by observing the lane lines. A video for the presented work is available online, https://youtu.be/76ciJmIHMD8 or https://v.youku.com/v_show/id_XNDM4ODc0MTM4NA==.html.

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Hierarchical Architecture for Computational Offloading in Autonomous Vehicle Environment

2019 29th International Telecommunication Networks and Applications Conference (ITNAC) ◽

10.1109/itnac46935.2019.9077995 ◽

2019 ◽

Author(s):

Arslan Rasheed ◽

Asim Anwar ◽

Arun Kumar ◽

Peter Han Joo Chong ◽

Xue Jun Li

Keyword(s):

Autonomous Vehicle ◽

Hierarchical Architecture ◽

Computational Offloading

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A novel path tracking approach considering safety of the intended functionality for autonomous vehicles

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/09544070211020535 ◽

2021 ◽

pp. 095440702110205

Author(s):

Huiran Wang ◽

Qidong Wang ◽

Wuwei Chen ◽

Linfeng Zhao ◽

Dongkui Tan

Keyword(s):

Autonomous Vehicles ◽

Autonomous Vehicle ◽

Coordinated Control ◽

Steering System ◽

Front Wheel ◽

Path Tracking ◽

Hierarchical Architecture ◽

Automatic Steering ◽

The Stability ◽

Control Layer

To reduce the adverse effect of the functional insufficiency of the steering system on the accuracy of path tracking, a path tracking approach considering safety of the intended functionality is proposed by coordinating automatic steering and differential braking in this paper. The proposed method adopts a hierarchical architecture consisting of a coordinated control layer and an execution control layer. In coordinated control layer, an extension controller considering functional insufficiency of the steering system, tire force characteristics and vehicle driving stability is proposed to determine the weight coefficients of automatic steering and the differential braking, and a model predictive controller is designed to calculate the desired front wheel angle and additional yaw moment. In execution control layer, a H∞ steering angle controller considering external disturbances and parameter uncertainty is designed to track desired front wheel angle, and a braking force distribution module is used to determine the wheel cylinder pressure of the controlled wheels. Both simulation and experiment results show that the proposed method can overcome the functional insufficiency of the steering system and improve the accuracy of path tracking while maintaining the stability of the autonomous vehicle.

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Hierarchical architecture of polyaniline nanoneedle arrays on electrochemically exfoliated graphene for supercapacitors and sodium batteries cathode

Materials & Design ◽

10.1016/j.matdes.2019.108440 ◽

2020 ◽

Vol 188 ◽

pp. 108440 ◽

Cited By ~ 6

Author(s):

Yingjuan Sun ◽

Liansheng Jiao ◽

Dongxue Han ◽

Faxing Wang ◽

Panpan Zhang ◽

...

Keyword(s):

Hierarchical Architecture ◽

Exfoliated Graphene ◽

Sodium Batteries

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Architectural and functional classification of smart grid solutions

Energy Informatics ◽

10.1186/s42162-019-0083-1 ◽

2019 ◽

Vol 2 (S1) ◽

Author(s):

Friederike Wenderoth ◽

Elisabeth Drayer ◽

Robert Schmoll ◽

Michael Niedermeier ◽

Martin Braun

Keyword(s):

Smart Grid ◽

Power Systems ◽

Power System ◽

Power Distribution ◽

Hierarchical Architecture ◽

Distribution Grid ◽

Active System ◽

System Operation ◽

Power System Operation

Abstract Historically, the power distribution grid was a passive system with limited control capabilities. Due to its increasing digitalization, this paradigm has shifted: the passive architecture of the power system itself, which includes cables, lines, and transformers, is extended by a communication infrastructure to become an active distribution grid. This transformation to an active system results from control capabilities that combine the communication and the physical components of the grid. It aims at optimizing, securing, enhancing, or facilitating the power system operation. The combination of power system, communication, and control capabilities is also referred to as a “smart grid”. A multitude of different architectures exist to realize such integrated systems. They are often labeled with descriptive terms such as “distributed,” “decentralized,” “local,” or “central." However, the actual meaning of these terms varies considerably within the research community.This paper illustrates the conflicting uses of prominent classification terms for the description of smart grid architectures. One source of this inconsistency is that the development of such interconnected systems is not only in the hands of classic power engineering but requires input from neighboring research disciplines such as control theory and automation, information and telecommunication technology, and electronics. This impedes a clear classification of smart grid solutions. Furthermore, this paper proposes a set of well-defined operation architectures specialized for use in power systems. Based on these architectures, this paper defines clear classifiers for the assessment of smart grid solutions. This allows the structural classification and comparison between different smart grid solutions and promotes a mutual understanding between the research disciplines. This paper presents revised parts of Chapters 4.2 and 5.2 of the dissertation of Drayer (Resilient Operation of Distribution Grids with Distributed-Hierarchical Architecture. Energy Management and Power System Operation, vol. 6, 2018).

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