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81.
Jeanbourquin D Sage D Nguyen L Schaeli B Kayal S Barry DA Rossi L 《Water science and technology》2011,64(5):1108-1114
Discharges of combined sewer overflows (CSOs) and stormwater are recognized as an important source of environmental contamination. However, the harsh sewer environment and particular hydraulic conditions during rain events reduce the reliability of traditional flow measurement probes. An in situ system for sewer water flow monitoring based on video images was evaluated. Algorithms to determine water velocities were developed based on image-processing techniques. The image-based water velocity algorithm identifies surface features and measures their positions with respect to real world coordinates. A web-based user interface and a three-tier system architecture enable remote configuration of the cameras and the image-processing algorithms in order to calculate automatically flow velocity on-line. Results of investigations conducted in a CSO are presented. The system was found to measure reliably water velocities, thereby providing the means to understand particular hydraulic behaviors. 相似文献
82.
83.
In this paper, a new algorithm, named VICUR, is presented for curve reconstruction problem. From a set of unorganized points, the proposed algorithm can construct curves that look natural to human vision. The VICUR algorithm is based on two connectivity criteria: proximity and good continuation from the prominent Gestalt principles of perception. Experimental results are presented to show the effectiveness of VICUR. 相似文献
84.
Xiaoyu Wang Wen Wang Yong Huang Nhan Nguyen Kalmanje Krishnakumar 《Journal of Intelligent Manufacturing》2008,19(4):383-396
Hard turning with cubic boron nitride (CBN) tools has been proven to be more effective and efficient than traditional grinding
operations in machining hardened steels. However, rapid tool wear is still one of the major hurdles affecting the wide implementation
of hard turning in industry. Better prediction of the CBN tool wear progression helps to optimize cutting conditions and/or
tool geometry to reduce tool wear, which further helps to make hard turning a viable technology. The objective of this study
is to design a novel but simple neural network-based generalized optimal estimator for CBN tool wear prediction in hard turning.
The proposed estimator is based on a fully forward connected neural network with cutting conditions and machining time as
the inputs and tool flank wear as the output. Extended Kalman filter algorithm is utilized as the network training algorithm
to speed up the learning convergence. Network neuron connection is optimized using a destructive optimization algorithm. Besides
performance comparisons with the CBN tool wear measurements in hard turning, the proposed tool wear estimator is also evaluated
against a multilayer perceptron neural network modeling approach and/or an analytical modeling approach, and it has been proven
to be faster, more accurate, and more robust. Although this neural network-based estimator is designed for CBN tool wear modeling
in this study, it is expected to be applicable to other tool wear modeling applications. 相似文献
85.
Bensalem S. Gallien M. Ingrand F. Kahloul I. Nguyen Thanh-Hung 《Robotics & Automation Magazine, IEEE》2009,16(1):67-77
Autonomous robots are complex systems that require the interaction or cooperation of numerous heterogeneous software components. Nowadays, robots are getting closer to humans and as such are becoming critical systems that must meet safety properties including logical, temporal, and real-time constraints. 相似文献
86.
This paper presents theoretical and experimental investigations on electroosmotic control of stream width in hydrodynamic
focusing. In the experiments, three liquids (aqueous NaCl, aqueous glycerol and aqueous NaCl) are introduced by syringe pumps
to flow side by side in a straight rectangular microchannel. External electric fields are applied on the two aqueous NaCl
streams. Under the same inlet volumetric flow rates, the applied electric fields are varied to control the interface positions
and consequently the width of the focused aqueous glycerol stream. The electroosmotic effect on the width of the aqueous glycerol
is measured using fluorescence imaging technique. The electroosmotic effect under different flow rates, different viscosity,
and aspect ratio are investigated. The results indicate that the electroosmotic effect on the pressure-driven flow becomes
weaker with the increase in flow rates, viscosity ratio or aspect ratio of the channel. The measured results of the focused
width of the non-conducting fluid agree well with the analytical model. 相似文献
87.
Ming Yi Thi Dao Nguyen Huan Liu Yafang Liu Shu Xiong Yan Wang 《Advanced functional materials》2023,33(26):2213471
Membrane decorated with biocides is an effective way to suppress biofilm growth. However, their immediate biocidal effect usually suffers from a significant decline due to the irreversible consumption of the biocides. Here, a smart nanofiltration membrane is reported with rechargeable antibacterial capability that is fabricated by a facile interfacial polymerization via 3-aminophenylboronic acid and trimesoyl chloride on a polysulfone substrate. Biocides bearing diol groups can be grafted onto the membrane surface under neutral/alkaline condition and then released from the surface under acidic environment, due to the pH-responsive feature of boronate ester complexes. The resultant membrane exhibits integrated properties of fast bacterial inactivating efficiency, rechargeable antibacterial capability, and impressive stability. In addition, the achieved membrane shows remarkable separation efficiency to dye/monovalent salt system. The successful fabrication of the membrane with rechargeable anti-bacterial property provides new insights into the development of pH-responsive and sustainable antibacterial membranes. 相似文献
88.
Thanh Hai Nguyen Phan Khanh Linh Tran Van An Dinh Duy Thanh Tran Nam Hoon Kim Joong Hee Lee 《Advanced functional materials》2023,33(7):2210101
Development of multifunctional electrocatalysts with high efficiency and stability is of great interest in recent energy conversion technologies. Herein, a novel heteroelectrocatalyst of molecular iron complex (FeMC)-carbide MXene (Mo2TiC2Tx) uniformly embedded in a 3D graphene-based hierarchical network (GrH) is rationally designed. The coexistence of FeMC and MXene with their unique interactions triggers optimum electronic properties, rich multiple active sites, and favorite free adsorption energy for excellent trifunctional catalytic activities. Meanwhile, the highly porous GrH effectively promotes a multichannel architecture for charge transfer and gas/ion diffusion to improve stability. Therefore, the FeMC–MXene/GrH results in superb performances towards oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline medium. The practical tests indicate that Zn/Al–air batteries derived from FeMC–MXene/GrH cathodic electrodes produce high power densities of 165.6 and 172.7 mW cm−2, respectively. Impressively, the liquid-state Zn–air battery delivers excellent cycling stability of over 1100 h. In addition, the alkaline water electrolyzer induces a low cell voltage of 1.55 V at 10 mA cm−2 and 1.86 V at 0.4 A cm−2 in 30 wt.% KOH at 80 °C, surpassing recent reports. The achievements suggest an exciting multifunctional electrocatalyst for electrochemical energy applications. 相似文献
89.
Nguyen Dieu My T. Fard Golnar Gharooni Atkins Ashley Bontempo Paul Iuzzolino Michael L. Peleg Orit 《Artificial Life and Robotics》2023,28(1):1-7
Artificial Life and Robotics - Honey bees (Apis mellifera L.) are social insects that makes frequent use of volatile pheromone signals to collectively navigate unpredictable and unknown... 相似文献
90.
Cuong-Le Thanh Nghia-Nguyen Trong Khatir Samir Trong-Nguyen Phuoc Mirjalili Seyedali Nguyen Khuong D. 《Engineering with Computers》2022,38(4):3069-3084
Engineering with Computers - Structural health monitoring (SHM) and Non-destructive Damage Identification (NDI) using responses of structures under dynamic excitation have an imperative role in the... 相似文献