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Liu, Yang,Wang, Xiaofeng,Liu Li,Wu, Bin,Yang, Qin Techno-Press 2022 Advances in nano research Vol.13 No.1
The present research investigates the dynamic behavior of a rotating functionally graded (FG) nonlocal cylindrical beam. The cylindrical beam is mathematically modeled via third-order beam theory linked with nonlocal strain gradient theory. The tube structure is made of functionally graded materials composed of Aluminum oxide coated on the Nickel, which the mechanical properties vary in the tube radius direction according to the power law. The bending harmonic force is applied in the tube length middle. The nonlocal spinning equations of the tube are derived via the energy method of the Hamilton principle, and they are solved via a robust numerical procedure for different boundary conditions. The main application of the rotating nanostructures is for the production of small-scale motors and devices and the drug-delivery application, the presented results can help the researcher have a better view regarding the different conditions.
Xiaofeng Liu,Qiang Chen,Zhong-Ren Peng,Li-Ye Zhang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.8
Traffic surveillance of mountain roads accords problems of high risk, low efficiency, and high cost; thus, unmanned aerial vehicles (UAVs) are introduced for traffic surveillance, working in conjunction with a delivery van. UAVs are assigned to monitor the high-risk road segments, while the low-risk segments are monitored by the delivery van. UAVs take off from and return to the delivery van to improve the speed and flexibility of the traffic surveillance, with reduced risk. First, a real-time and coordinated UAV path-planning problem is presented, in which the number of monitored targets is dynamic and the delivery van is moving. Then, a multi-objective optimization model is proposed to minimize both the coordination value of UAV flight distance and the number of UAVs used. Next, a penalty-based boundary intersection optimization algorithm is proposed, which adopts the decomposition strategy and Pareto technique to acquire the optimized paths in real-time. In addition, a case study is implemented to compare the proposed algorithm with two commonly used algorithms and the results indicate that the proposed algorithm performs better with respect to solution quality and calculation time. Moreover, the cost versus performance of the UAV traffic surveillance was analyzed. This demonstrates that it is effective to use the proposed approach to conduct real-time and coordinated UAV path planning. Finally, the limitations and prospects of UAV traffic surveillance are presented.
Opto-mechanical Design of Monocrystalline Silicon Mirror for a Reflective Imaging Optical System
Xiaofeng Liu,Xin Zhang,Fuxiang Tian 한국광학회 2022 Current Optics and Photonics Vol.6 No.3
Monocrystalline silicon has excellent properties, but it is difficult to design and manufacture siliconbased mirrors that can meet engineering applications because of its hard and brittle properties. This paper used monocrystalline silicon as the main mirror material in an imaging system to carry out a feasibility study. The lightweight design of the mirror is completed by the method of center support and edge cutting. The support structure of the mirror was designed to meet the conditions of wide temperature applications. Isight software was used to optimize the feasibility sample, and the optimized results are that the root mean square error of the mirror surface is 3.6 nm, the rigid body displacement of the mirroris 2.1 μm, and the angular displacement is 2.5″ under the conditions of a temperature of Δ20 ℃ and agravity load of 1 g. The optimized result show that the silicon-based mirror developed in this paper can meet the requirements of engineering applications. This research on silicon-based mirrors can provide guidance for the application of other silicon-based mirrors.
Xiaofeng Liu,Pei Hang 한국마케팅과학회 2006 마케팅과학연구 Vol.16 No.4
Product quality of perishable food is significantly affected by the environment. Technological approaches for tracking and tracing such products have attracted increasing attentions in both research and practice. This paper studies how supermarket can maximize profits of selling perishable food through price adjustment based on real-ime product quality and values. This can be achieved by tracing the value of the perishable food based on an automatic product identification technology padio Frequency Identification (RFID). With the support of the RFID, an aptimizaiton model can be developed to enable product tracking and tracing. The analysis of the model shows promising benefits of applying a dynamic pricing policy and obtains the optimal ordering decision in the respect of deterministic demand function.
An Improved Hybrid Kalman Filter Design for Aircraft Engine based on a Velocity-Based LPV Framework
Liu, Xiaofeng The Korean Society for Aeronautical and Space Scie 2017 International Journal of Aeronautical and Space Sc Vol.18 No.3
In-flight aircraft engine performance estimation is one of the key techniques for advanced intelligent engine control and in-flight fault detection, isolation and accommodation. This paper detailed the current performance degradation estimation methods, and an improved hybrid Kalman filter via velocity-based LPV (VLPV) framework for these needs is proposed in this paper. Composed of a nonlinear on-board model (NOBM) and VLPV, the filter shows a hybrid architecture. The outputs of NOBM are used for the baseline of the VLPV Kalman filter, while the system performance degradation factors on-line estimated by the measured real system output deviations are fed back to the NOBM for its updating. In addition, the setting of the process and measurement noise covariance matrices' values are also discussed. By applying it to a commercial turbofan engine, simulation results show the efficiency.
Liu, Xiaofeng,Hang, Pei Korean Academy of Marketing Science 2006 마케팅과학연구 Vol.16 No.4
Product quality of perishable food is significantly affected by the environment. Technological approaches for tracking and tracing such products have attracted increasing attentions in both research and practice. This paper studies how supermarket can maximize profits of selling perishable food through price adjustment based on real-ime product quality and values. This can be achieved by tracing the value of the perishable food based on an automatic product identification technology Radio Frequency Identification(RFID). With the support of the RFID, an optimization model can be developed to enable product tracking and tracing. The analysis of the model shows promising benefits of applying a dynamic pricing policy and obtains the optimal ordering decision in the respect of deterministic demand function.
An Improved Hybrid Kalman Filter Design for Aircraft Engine based on a Velocity-Based LPV Framework
Xiaofeng Liu 한국항공우주학회 2017 International Journal of Aeronautical and Space Sc Vol.18 No.3
In-flight aircraft engine performance estimation is one of the key techniques for advanced intelligent engine control and in-flight fault detection, isolation and accommodation. This paper detailed the current performance degradation estimation methods, and an improved hybrid Kalman filter via velocity-based LPV (VLPV) framework for these needs is proposed in this paper. Composed of a nonlinear on-board model (NOBM) and VLPV, the filter shows a hybrid architecture. The outputs of NOBM are used for the baseline of the VLPV Kalman filter, while the system performance degradation factors on-line estimated by the measured real system output deviations are fed back to the NOBM for its updating. In addition, the setting of the process and measurement noise covariance matrices’ values are also discussed. By applying it to a commercial turbofan engine, simulation results show the efficiency.