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2019, 39(4): .

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2019, 39(4): .

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Abstract:

Test Monitoring System of Air Blast Shockwave Power Based on Satellite Communication

LÜ Zhong-jie, HAN Jin-liang, HUANG Feng-lei

2019, 39(4): 331-336,440. doi:10.15918/j.tbit1001-0645.2019.04.001

Abstract(1263) PDF(503)

Abstract:
To solve the problems of bad test environment, long safety distance, inability to monitor test equipment and difficult data recovery in the process of measuring the shockwave of large equivalent charge blast, a storage testing technology and satellite communication technology were used to study a shockwave power testing system about large-equivalent charge. A system design scheme and implementation method were obtained. The system can perform wireless data transmission of any distance in any environment based on satellite communication technology. The wireless remote monitoring of test equipment and rapid data transmission of test data can be achieved in the system. The system cannot only save a lot of manpower and time but also effectively improve the reliability and stability of testing. The transmission function of system was tested in the state of network debugging assistant simulation and actual explosion testing. The test results are consistent with the theoretical calculation results. The results show that the developed system has accurate test data and high transmission reliability, and can meet the actual test requirements of charge shock wave overpressure in complex and harsh environments. It has good application prospects.

Penetration Resistance and Layers Mutual Effect of Polyurea Coated Structures

ZHANG Peng, WANG Zhi-jun, ZHAO Peng-duo, ZHANG Lei, LIU Han, XU Yu-xin

2019, 39(4): 337-342,358. doi:10.15918/j.tbit1001-0645.2019.04.002

Abstract(1097) PDF(406)

Abstract:
Polyurea elastomer coated steel plates and coated fiber reinforced composite laminates were investigated on their penetration resistance and layers' mutual effect. Ballistic experiment of two polyurea coated substrates subjected to 3.3 g cubic fragments was conducted. Ballistic limits of three coating types of structures-uncoated, impact side coated and rear side coated-were obtained. Penetration resistance of different polyurea coated structures was analyzed with the deformation and failure characteristic. Experimental results indicate that the effect of polyurea coating on penetration resistance is related to energy absorption mechanism of each substrate;the forms of energy absorption of steel plates include partial deformation and shear plugging. Energy consumption of steel plates is hardly affected by coating. Polyurea coating can improve penetration resistance of coated steel plates and the effect of front-side coating is superior to that of back-side coating; back-side coating can inhibit the energy absorption of fiber plates and significantly reduce penetration resistance.

Concrete Crack Region Detection Based on High-Dimensional Image Feature Compressed Sensing

WANG Bao-xian, WANG Zhe, ZHANG Yu-feng, ZHAO Wei-gang, LI Yi-qiang, WANG Kai

2019, 39(4): 343-351. doi:10.15918/j.tbit1001-0645.2019.04.003

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Abstract:
With the simple and naive feature representation, the concrete crack region detection is sensitive for the illumination and background disturbances. Through multifold image region feature extraction models, massive and rich texture features of image region can be obtained, thereby leading to a better crack detecting accuracy. However, with the high dimensional features, the resultant crack region detection would be suffered from a huge data storage and computational burden. To address this problem mentioned above, a novel crack region detector based on high dimensional image feature compressed sensing was presented. Specifically, based upon Johnson-Lindenstrauss lemma, a good discrimination between crack and non-crack region samples can be achieved using a fewer compressed region features. Then, least square support vector machine was utilized for efficiently separating the compressed crack features and non-crack ones. Plenty experiments on practically collected concrete images demonstrate that the training efficiency of developed crack detector is more than 150 times faster than that of high-dimensional features. Meanwhile, our crack region detecting accuracy is 90.3%, and the crack detecting recall rate can reach 91.2%, which is superior to other compared crack detection methods.

Numerical Simulation on Cushion Effect of Packaging Container with Configuration Design

CHEN Xin-fa, YE Tian, LI Yu-long, SUO Tao

2019, 39(4): 352-358. doi:10.15918/j.tbit1001-0645.2019.04.004

Abstract(755) PDF(393)

Abstract:
Three packaging containers with configuration design were proposed according to material plastic deformation and energy dissipation theory. Numerical simulations of packaging container dynamic behavior under several drop conditions were carried out using finite element analysis software Abaqus/Explicit. Drop altitudes of normal, transverse and oblique impact were taken into account, and the drop height was 50 meters in the simulations. Stress and deformation distribution of container subjected to different impact cases were gained. Impact cushion properties of the three containers were discussed. The numerical results indicate the containers with configuration design can withstand the impact of 50 m free fall. Thin shell bulge and wide plateau stress are mainly energy dissipation ways for cushion material. It will help improve protected object's safety under impact environment.

The Direction Finding Distribution of GNSS Interference on the Condition of Multipath

CHEN Shu-xin, CHEN Jian-hua, WU Hao, YUE Long-hua

2019, 39(4): 359-364. doi:10.15918/j.tbit1001-0645.2019.04.005

Abstract(1207) PDF(431)

Abstract:
In order to carry out the research on locating the source of global navigation satellite system (GNSS) interference, a model of multipath fading of the interference phase was built and a method of depicting the direction finding distribution was proposed according to the multipath propagation of the interference. Firstly, direction finding model and its theoretical error were listed aiming at GNSS interference. Then, the relationship between phase distribution and Rician factor was simulated and analyzed on the condition of multipath. By the means of inferring the PDF (probability density function,) of phase, a mathematical model of the phase of GNSS interference was built. Finally, a research on the relationship between direction finding distribution and Rician factor along with DOA was carried out, taking advantage of the Monte Carlo simulation. The theoretical derivation and simulation results indicate that the phase of interference follows Gaussian distribution on the condition of multipath when the Rician factor is pretty large. The variance of direction finding decreases with the increase of Rician factor. The variance is the minimum when the moment DOA is perpendicular to the base line. And the confidence interval tends to stable with the same confidence level while Rician factor is more than 20.

Infrared Radiation Characteristics Calculation and Infrared Stealth Effect Analysis of Stealth Fighter

WANG Biao, CONG Wei, WANG Chao-zhe, YANG Yong-jian, HUANG Jin-ke

2019, 39(4): 365-371. doi:10.15918/j.tbit1001-0645.2019.04.006

Abstract(1137) PDF(701)

Abstract:
Aiming at the urgent need of the development of infrared stealth technology and anti-stealth technology, a simulation model of infrared image of stealth aircraft was established, and the effect of infrared stealth of stealth aircraft was quantitatively evaluated. Firstly, the infrared stealth modeling was accomplished for the two-dimensional exhaust, low emissivity skin, engine room insulation and cold air injection based on the infrared radiation calculation model of the aircraft, and the infrared image of the stealth aircraft was generated through rendering. Then the stealth effect of three infrared stealth measures including low emissivity skin, engine room insulation and cold air injection were analyzed. The simulation results show that the stealth fighter radiation varies greatly under different stealth measures.

Real-Time and Immersive Simulation of Chinese Calligraphy Brush

HUANG Dong, AN Wei-hua, ZHANG Wen-ting

2019, 39(4): 372-377. doi:10.15918/j.tbit1001-0645.2019.04.007

Abstract(895) PDF(316)

Abstract:
A real-time simulation technique for writing behavior of Chinese calligraphy brush was presented. In terms of the geometric shape of brush, the modeling method of the skin-skeleton was adopted, and a fast algorithm for the rotation parameters of the bone was proposed, which realized the two deformation effects of the pen head during the movement process; in terms of the ink effect, the ink diffusion model based on the particle system was adopted, and it could flexibly control the effect of ink on the paper surface. Based on the above techniques, using a head-mounted display and a force feedback device, a brush writing simulation system was implemented. Results show the better real-time and immersive feeling.

Control Strategy of Power Parafoil System Based on Coupling Compensation

TAN Pan-long, LUO Shu-zhen, SUN Qing-lin

2019, 39(4): 378-383. doi:10.15918/j.tbit1001-0645.2019.04.008

Abstract(805) PDF(293)

Abstract:
Powered parafoil system is strongly nonlinear and contains complicated cross-coupling characteristic, which makes the system hard to control. Under the variable wind disturbance, this coupling influence will aggravate the control performance, probably resulting in large deviations or instability in the control process. An active disturbance rejection control (ADRC) strategy based on the coupling compensation was proposed. The dynamic cross-coupling relation of the longitudinal thrust on the lateral yaw control was designed as the known disturbance of extended state observer (ESO) to be compensated in the improved control law, so that the tracking ability of the controller could be enhanced. Moreover, under the cross-coupling compensation, a complex nonlinear powered parafoil system was constructed as integrators which could be easily controlled, such that the tracking precision and disturbance rejection capacity of the lateral controller were improved. Eventually, mathematical simulations demonstrate that the proposed control approach has better tracking performance and robustness compared with the conventional ADRC and PID.

Robust Gate Assignment Considering Buffer Time Cost

FENG Xia, WANG Qing-zhao

2019, 39(4): 384-390. doi:10.15918/j.tbit1001-0645.2019.04.009

Abstract(763) PDF(280)

Abstract:
Aiming at the perturbation of gate assignment caused by flight operation in early or delay, analyzing the distribution rule of deviation between actual arrival-departure time and plan time of flights in actual operation of airport, a robust evaluation function of gate assignment based on buffer time cost was proposed. On this basis, taking the minimum of buffer time cost, gate-flight size difference and the number of remote gates as the optimization objective, a robust gate assignment model was established. At the same time, a tabu search algorithm was designed to solve the model. The results of model verification based on the actual operating data of two typical working day at Capital International Airport show that, compared with no considering robustness scheme and the traditional method of minimizing the sum of the dispersion square of gate idle time, the flight conflicts are reduced by 98.1% and 97.6% respectively on A day and reduced by 74.3% and 70.8% respectively on B day with the proposed methods, improving the robustness of the gate assignment plan effectively.

Manipulator Robust Trajectory Tracking Control for Electric Power Operation Robot in Semi-Structured Environment

JIANG Wei, WANG Jie, CHEN Wei, YU Lian-qing, LI Hong-jun, WU Gong-ping

2019, 39(4): 391-398. doi:10.15918/j.tbit1001-0645.2019.04.010

Abstract(989) PDF(390)

Abstract:
In order to effectively suppress the influence of disturbance signals and a variety of uncertainties on tracking precision and stability of manipulator for transmission line electric power operation robot in a harsh semi-structured environment with high voltage and strong electromagnetic interference, a robot manipulator trajectory tracking robust control method based on H∞ control theory was proposed in this paper. Firstly, layering robot control architecture, the different dynamic behaviors of robot were modeled based on Lagrange method and armature voltage equation, obtaining a mapping model of robot kinetic behaviors and kinetic parameters. Then on this basis, the space state expression of the manipulator joint motion control under the condition of disturbances and uncertainties was deduced, a manipulator motion H∞ control model was established, and the control system H∞ controller for manipulator trajectory tracking was also solved with linearity matrix inequality (LMI). Finally, the simulation and field operation experiments were carried out. The results show the effectiveness of the H∞ control, the engineering feasibility of the control method, and the remarkable characteristics in sound universality, adaptability and easy expansion.

RUL Prediction Oriented Parallel Simulation Technology for Hybrid Degradation Equipment

GE Cheng-long, ZHU Yuan-chang, DI Yan-qiang, MENG Xian-guo

2019, 39(4): 399-405. doi:10.15918/j.tbit1001-0645.2019.04.011

Abstract(1124) PDF(287)

Abstract:
Aiming at the remaining useful life (RUL) prediction issue of hybrid degradation equipment with discrete shock, a parallel simulation technology was studied to predict the RUL of hybrid degradation equipments. Firstly, a simulation model was proposed based on a hybrid Wiener state space model, taking the arrival of Poisson shock as the selection criteria of the model. Driven by the real-time degradation data, the online simulation model selection was carried out, realizing the data assimilation of simulation model and online estimation of unknown parameter with a strong tracking filter and expectation maximum algorithm. And it was accomplished to evolve the model and improve the fidelity of simulation model. As a result, the parallel simulation based real-time prediction of RUL was realized. Then, utilizing the degradation data of a bearing, the proposed method was verified. The simulation results show that the parallel simulation method can simulate the performance degradation process effectively, and can predict the RUL with less uncertainty and high accuracy.

Prediction for the Remaining Useful Life of Lithium-ion Battery Based on PCA-NARX

PANG Xiao-qiong, WANG Zhu-qing, ZENG Jian-chao, JIA Jian-fang, SHI Yuan-hao, WEN Jie

2019, 39(4): 406-412. doi:10.15918/j.tbit1001-0645.2019.04.012

Abstract(1351) PDF(313)

Abstract:
The current data-driven remaining useful life (RUL) prognostics methods generally have the limitation that cannot be well adapted to the prediction for different batteries, along with low prediction accuracy caused by the redundancy or deficiency of health indictors (HIs).To solve the problem, integrating the PCA-based feature fusion method and NARX neural network, an indirect RUL prognostics framework was proposed for lithium-ion battery. Firstly, multiple measurable parameters that could reflect the performance degradations of lithium-ion battery were selected as candidate HIs, and then the HI was extracted based on PCA to eliminate the redundancy. Furthermore, both health factor and capacity prediction models based on NARX-NN were established using a set of battery life data. Taking the HIs of early stage as the input, the RUL of different batteries with the same type could be predicted indirectly. Finally, sufficient experiments were carried out to validate the high efficiency and adaptability of the proposed method for the same type lithium-ion battery.

Modeling and Pressure Control of Integrated Electro-Hydraulic Brake System

SHANGGUAN Wen-bin, LIANG Tu-qiang, JIANG Kai-hong, TANG Wen

2019, 39(4): 413-418. doi:10.15918/j.tbit1001-0645.2019.04.013

Abstract(1007) PDF(286)

Abstract:
A fifth-order model for I-EHB (integrated electro-hydraulic brake) system was derived from its mechanical and hydraulic subsystems. The model was linearized at equilibrium states, and then the transfer functions of the I-EHB system were obtained and verified by AMESim software. A cascade controller composed with position and pressure control was designed based on PID control. The control process was arranged that, while the position of the piston was in the deadzone of servo master cylinder, the piston was controlled to move to cover the pressure compensated orifice with position feedback, once the piston was beyond the deadzone, the cascaded controller could be switched into pressure control. Results with the cascade controller show that, the response time of the pressure in the servo master cylinder is less than 80 ms and the overshoot is within 6%, which helps improving the braking safety and comfort.

Variational Problems of the Functional of Parallel-Type Inner Product Tensor with Hamiltonian Operators

LAO Da-zhong, ZHANG Yan-di, YANG Ce

2019, 39(4): 419-426. doi:10.15918/j.tbit1001-0645.2019.04.014

Abstract(965) PDF(380)

Abstract:
The variational problems of the functional depending on parallel-type inner product tensor in the calculus of variations were discussed, the tensor in the functional can include Hamiltonian operator namely the gradient, divergence and curl operator. According to the parallel-type and serial-type inner product operation rules of then-th order tensor, the fundamental lemma of the variational operations of the functional depending on the tensor was given. The theorem of the variational problem of the functional depending on the tensor with Hamiltonian operators was proposed and proved; Through making directly variation to the tensors with Hamiltonian operators, the Euler equation and the corresponding natural boundary conditions were obtained. The correctness of the Euler equation was verified with some functional examples. The connotation of the dajoint operator was extended, the conception of the right adjoint operator was proposed, the relationships between the adjoint operator or self-adjoint operator and the gradient, divergence and curl operator were discussed, it is pointed out that the variational problem of the functional discussed is essentially operation conforming to the definition of adjoint operator operation or self-adjoint operator.

Identifying Topics of Online Healthcare Reviews Based on Improved LDA

GAO Hui-ying, LIU Jia-wei, YANG Shu-xin

2019, 39(4): 427-434. doi:10.15918/j.tbit1001-0645.2019.04.015

Abstract(1332) PDF(314)

Abstract:
An in-depth research was conducted on the use of topic models to identify the topics of healthcare services. In view of semantic sparseness and the lack of co-occurrence information in the special extraction of healthcare reviews in the LDA topic model, a CO-LDA model was proposed based on word co-occurrence analysis combined with LDA topic model. Firstly, the word co-occurrence analysis method was used to analyze the corpus of the review and the word co-occurrence matrix was obtained. Secondly, the LDA topic model was used to represent corpus reviews, and then the hierarchical clustering algorithm was used to classify the features. Finally, patients' focus on healthcare service quality factors was identified. Based on the average minimum JS distance, the average Kendall correlation coefficient and the average TF-IDF, in this paper the CO-LDA model was compared with the traditional LDA model. The experiment finally shows that the recognition theme consistency of CO-LDA model is better than that of the LDA model. Through the comparison of the experimental results with the "Hospital Evaluation Standards" in China, it is found that the consistency of the former was high, which explains the effectiveness of the CO-LDA-based online medical review topic mining method.

Recycling Platform Strategy Based on Stackelberg Model

YANG Tian-jian, SONG Jing-xiu, YIN Ming-rui

2019, 39(4): 435-440. doi:10.15918/j.tbit1001-0645.2019.04.016

Abstract(793) PDF(295)

Abstract:
Considering the service effort of three-tier and four-tier cities, the optimal decision-making problem of the two-level supply chain composed of the platform and the channel was studied. The study found that decentralized decision-making could not achieve the maximization of recycling amount, second-hand mobile phone sales and profit, so Fixed Transfer Payment Method based on centralized decision making was designed to realize supply chain coordination. Further numerical examples were used to verify the impact of share ratio and consumer convenience sensitivity on supply chain decision-making and the tenability of relevant conclusions.

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