Harbin Engineering University

About: Harbin Engineering University is a education organization based out in Harbin, Heilongjiang, China. It is known for research contribution in the topics: Control theory & Microstructure. The organization has 31149 authors who have published 27940 publications receiving 276787 citations. The organization is also known as: HEU.

AUV local path planning based on virtual potential field

Abstract: We build a local path planning algorithm using virtual force for free local minimum. Potential field is used as a basic platform for the path planning since it has the advantages of simplicity, real-time computation. However, there is one shortcoming in the potential field: it may cause local minimum whenever the curvature of the repulsive equipotential curve is less than the curvature of the attractive equipotential curve at the same configuration. To get rid of the local minimum in the presence of obstacles, we present a navigation algorithm, which integrates virtual force concept with a potential-field-based method to maneuver autonomous underwater vehicle (AUV) in unknown or unstructured environments. This study focuses on the free local minimum in potential-field based navigation. We mainly consider the potential-field method in conjunction with virtual force concept as the basis of our navigation algorithm. Simulation and experiments of our algorithm shows good performance and ability to overcome the local minimum problem associated with potential field methods.

Multifunctional hydroxyapatite nanofibers and microbelts as drug carriers.

Abstract: Luminescent, mesoporous, and bioactive europium-doped hydroxyapatite (HAp:Eu(3+)) nanofibers and microbelts have been prepared by a combination of sol-gel and electrospinning processes with a cationic surfactant as template. The obtained multifunctional hydroxyapatite nanofibers and microbelts, which have mesoporous structure and red luminescence, were tested as drug carriers by investigating their drug-storage/release properties with ibuprofen (IBU) as model drug. X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution (HR) TEM, FTIR spectroscopy, N(2) adsorption/desorption, photoluminescence (PL) spectra, and UV/Vis spectroscopy were used to characterize the structural, morphological, textural, and optical properties of the resulting samples. The results reveal that the multifunctional hydroxyapatites exhibit irregular mesostructure, and have fiberlike and beltlike morphologies with sizes of several hundred nanometers in width and several millimeters in length. The IBU-loaded HAp:Eu(3+) system shows red luminescence of Eu(3+) ((5)D(0)-(7)F(0,1,2)) under UV irradiation and controlled release of IBU. In addition, the emission intensity of Eu(3+) in the drug carrier system varies with the released amount of IBU, and thus drug release can be easily tracked and monitored by the change in luminescence intensity.

In-Situ Fabrication of MOF-Derived Co−Co Layered Double Hydroxide Hollow Nanocages/Graphene Composite: A Novel Electrode Material with Superior Electrochemical Performance

Abstract: Rational design of a transition metal layered double hydroxide (LDH) and graphene composite is vitally important for designing high-performance supercapacitor electrodes. Although various methods are performed, the realization of high-performance is still impeded by the agglomeration of graphene and layered double hydroxide. Here, metal–organic framework derived cobalt–cobalt layered double hydroxide (Co−Co LDH) hollow nanocages, uniformly deposited on graphene nanosheets, are fabricated through facile in situ co-deposition and thermal ion-exchange reaction. Electrochemical investigation reveals that Co−Co LDH/15 mg graphene is rather outstanding, which delivers high specific capacitance of 1205 F g−1, excellent rate capability (60.3 % capacitance retention is obtained after the current density increased 6.67 times), and cycling stability. The excellent performance of electrode is also confirmed by assembling an asymmetric supercapacitor, which delivers high energy density of 49.5 Wh kg−1 as well as the maximum power density of 7000 W kg−1. The Co−Co LDH/graphene composite proves a promising concept for constructing hierarchical structure materials in the future.

EV-Gait: Event-Based Robust Gait Recognition Using Dynamic Vision Sensors

Abstract: In this paper, we introduce a new type of sensing modality, the Dynamic Vision Sensors (Event Cameras), for the task of gait recognition. Compared with the traditional RGB sensors, the event cameras have many unique advantages such as ultra low resources consumption, high temporal resolution and much larger dynamic range. However, those cameras only produce noisy and asynchronous events of intensity changes rather than frames, where conventional vision-based gait recognition algorithms can’t be directly applied. To address this, we propose a new Event-based Gait Recognition (EV-Gait) approach, which exploits motion consistency to effectively remove noise, and uses a deep neural network to recognise gait from the event streams. To evaluate the performance of EV-Gait, we collect two event-based gait datasets, one from real-world experiments and the other by converting the publicly available RGB gait recognition benchmark CASIA-B. Extensive experiments show that EV-Gait can get nearly 96% recognition accuracy in the real-world settings, while on the CASIA-B benchmark it achieves comparable performance with state-of-the-art RGB-based gait recognition approaches.