PLA Logistical Engineering University
PLA Logistical Engineering University
The Logistical Engineering University of PLA or University of Logistics is an institution of higher learning located in Chongqing, focusing on military engineering. It is affiliated to the General Logistics Department of the People's Liberation Army of China, and is one of the leading military engineering academies in the country.The university was founded in 1961, and was named a national key university in 1979. Wikipedia.
Tu Y.-Q.,PLA Logistical Engineering University |
Shen Y.-L.,PLA Logistical Engineering University
Signal Processing | Year: 2017
To improve the precision of frequency estimation, a phase correction autocorrelation-based frequency estimation method for sinusoidal signal is proposed. Firstly, a phase correction autocorrelation is developed to reduce the effect of non-half period sampling signal on autocorrelation. Secondly, reference signal is generated according to phase correction autocorrelation signal. Finally, an error function between phase correction autocorrelation signal and reference signal is constructed and frequency estimation is obtained by calculating the minimum of error function. To demonstrate the superiority of the proposed method, computational complexity is analyzed, simulations and experiments are performed. Theoretical analysis and simulations demonstrate that the proposed method reduces the influence of non- half period sampling signal and has better frequency estimation performance than the interpolated DFT method, the modified covariance method for correlation, the two-stage autocorrelation method and the expanded autocorrelation method. The measurement experiments of LFMCW radars validate the effectiveness and superiority of the proposed method in practice. © 2016 Elsevier B.V.
Niu Z.,PLA Logistical Engineering University
Revista de la Facultad de Ingenieria | Year: 2016
The main focus of this paper is the analysis method for calculating dynamic reliability of wind-exposed linear structures under non-Gaussian response. Considering the squared component of the turbulence, the dynamic response of structure can be described through higher order moments and higher-order spectrums in frequency domain. Then the joint probability distributions between displacement and velocity can be estimated from response moments with A-type Gram-Charlier series until the seventh order. Thereby, crossing levels are determined and used for estimating the first passage dynamic reliability of the structure. A numerical example of a linear SDOF structure is carried out to demonstrate the usage of this method. Some parameters analysis between Gaussian and non-Gaussian model are also performed in the example.
Zheng Y.,PLA Logistical Engineering University
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2012
Solid material develops from elastic to plastic then to failure after undertaking some load, which means that yield is different from failure. The system of yield criteria for geomaterial is discussed and two definitions which are point failure and surface failure in stress field are put forward. And the criteria of surface whole failure is defined through traditional limit analysis method. Simultaneously, the deficiencies for traditional limit analysis and numerical analysis are pointed out by reviewing and analyzing the solution characteristics of traditional limit analysis method. Based on the combination of these two methods, a newly developed numerical limit analysis method is built, which has enlarged the application rage of limit analysis. The significances and features of traditional limit analysis method and numerical limit method are studied, as well as the reliabilities. The advantages and disadvantages of numerical limit analysis are listed; and the wide applicability of numerical limit analysis in the slope(landslide) engineering, foundation engineering and tunnel engineering is illustrated.
Zheng Y.,PLA Logistical Engineering University |
Qiu C.,PLA Logistical Engineering University
Modern Tunnelling Technology | Year: 2016
Protodyakonov's pressure arch theory has been a mechanical basis for the design of tunnels and underground works in China, but it has been questioned to some extent by academic and engineering fields. This paper analyzes the real meanings and formation conditions of a pressure arch using the FEM strength reduction method and a model test, researches the relationships among tunnel span, rock mass strength and pressure arch self-stability, and discusses the failure mechanism of tunnels under different buried depths. The results show that: 1) the pressure arch theory is only applicable to rectangular or gentle-vault tunnels with stable surrounding rocks and a shallow buried depth; 2) a pressure arch will not occur in an arched tunnel; 3) a self-stable pressure arch will not occur under very low rock strength and a too large tunnel span; 4) a pressure arch and tunnel failure will not occur in a tunnel with stable surrounding rock; 5) for a tunnel with a great buried depth, the failure first occurs on both sides, so the pressure arch theory is not applicable © 2016, Editorial Office of "Modern Tunnelling Technology". All right reserved.
Kong L.,CAS Wuhan Institute of Rock and Soil Mechanics |
Chen Z.,PLA Logistical Engineering University
Tumu Gongcheng Xuebao/China Civil Engineering Journal | Year: 2012
A brief introduction is provided on the overall trend of the global-wide research on special soils and slopes with a particular emphasis on the state of the practice in China on basic properties and engineering countermeasures for typical special soils such as collapsible loess, expansive soil and red clay. Recent achievements are pointed out as well as the major remaining problems in the field of special soils and slopes. The future research direction is also identified and a long list of relevant references is provided in the end of the paper.
Li H.,University of Missouri-St. Louis |
Jiang D.,PLA Logistical Engineering University
Computers and Operations Research | Year: 2012
We model the safety stock placement problem in general acyclic supply chain networks as a project scheduling problem, for which the constraint programming (CP) techniques are both effective and efficient in finding high quality solutions. We further integrate CP with a genetic algorithm (GA), which improves the CP solution quality significantly. The performance of our hybrid CPGA algorithm is evaluated on randomly generated test instances. CPGA is able to find optimal solutions to small problems in fractions of a second, and near optimal solutions of about 5% optimality gap to medium size problems in several minutes on average. © 2011 Elsevier Ltd. All rights reserved.
Li F.,University of Sichuan |
Zhou J.,University of Sichuan |
Wu D.,PLA Logistical Engineering University
Aerospace Science and Technology | Year: 2013
This paper addresses the optimal filtering problem for a class of uncertain dynamical systems with multiple packet dropouts and finite-step correlated observation noises. By rearranging the stochastic terms in the transmission and measurement matrices of the dynamical system into the noises directly, the process noises and observation noises in resulted system depend on the state as well as the stochastic uncertain perturbations, and are not only autocorrelated respectively but also cross-correlated. For this complicated dynamical system, instead of designing a Kalman-type filter, a globally optimal filtering in the minimum mean square error sense is developed by exploiting sufficiently the statistical properties of correlated noises. Numerical simulation is provided to demonstrate the performance of the proposed filter. © 2011 Elsevier Masson SAS.
Xu Y.,PLA Logistical Engineering University
International Journal of Simulation: Systems, Science and Technology | Year: 2016
In this paper, the author studies logistics distribution technology based on Internet of things. The traditional logistics information system cannot achieve the delivery accuracy. Sometimes proposed cargo is accurate, but to the guest’s hand goods may be wrong. The system development based on the platform of logistics information achieves the accurate results with good information aided by bar code scanning technology. It is very weak for the car temperature and humidity monitoring of the traditional logistics information system. The result shows that the performance of traditional logistic can be improved by using Internet of Things. © 2016, UK Simulation Society. All rights reserved.
Shen T.-A.,PLA Logistical Engineering University |
Tu Y.-Q.,PLA Logistical Engineering University |
Zhang H.-T.,PLA Logistical Engineering University
Review of Scientific Instruments | Year: 2014
The precision of frequency tracking method and phase difference calculation method affects the measurement precision of Coriolis Mass Flowmeter directly. To improve the accuracy of the mass flowrate, a novel signal processing method for Coriolis Mass Flowmeter is proposed for this time varying signal, which is comprised of a modified adaptive lattice notch filter and a revised sliding recursive discrete-time Fourier transform algorithm. The method cannot only track the change of frequency continuously, but also ensure the calculation accuracy when measuring phase difference. The computational load of the proposed method is small with higher accuracy. Simulation and experiment results show that the proposed method is effective. © 2014 AIP Publishing LLC.
Chen Z.-H.,PLA Logistical Engineering University |
Qin B.,PLA Logistical Engineering University
Yantu Lixue/Rock and Soil Mechanics | Year: 2012
Based on thermodynamics and stress theory of continuum mechanics, a series of stress state variables of unsaturated soils, which covered all stress state variables used in literature, are deduced from the equilibrium equation of soil skeleton. It is shown that there are more than five combinations of stress state variables for unsaturated soils, most of which are related to physical properties such as void ratio and degree of saturation. Stress state variables should have dimensions of stress, while void ratio, degree of saturation and their combination could not be regarded as stress state variables. Both the simplified Bishop's effective stress equation and the Fredlund's two stress state variables are simplified forms of stress state variables. The influence of void ratio is not included in the simplified Bishop's effective stress equation, while the dependence on void ratio and degree of saturation are neglected in the Fredlund's two stress state variables. When choosing stress state variables for unsaturated soils, rationality in theory and convenience in application as well as correctness in logic should be taken into account.