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2018, 38(4): .

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2018, 38(4): .

Abstract(637) PDF(503)

Abstract:

Numerical Simulation and Experiment Investigation on Hypervelocity Jetting Projectile Charge Formation

XU Bin, WANG Cheng, XU Wen-Long

2018, 38(4): 331-337. doi:10.15918/j.tbit1001-0645.2018.04.001

Abstract(1178) PDF(1038)

Abstract:
In order to increase the effective quality of shaped charge jets, a new type of hypervelocity JPC was proposed by the study of internal explosion of jet collision region and the study of the formation mechanism of hypervelocity JPC, which could break through the high speed limitation of jets. The relationship between hypervelocity JPC and the structure parameters of the shaped charge was studied through numerous simulation and theoretical analysis, and furthermore an experiment was conducted. The penetration result shows good agreement with the simulation result and the theoretical analysis. The penetration ability of hypervelocity JPC has been improved greatly compared with EFP and classical shaped charge and there is no need to change the standoff and the diameter of shaped charge.

Aerodynamic Characteristic Study Towards the Hedgehopping Terminal Sensitive Projectile at Rolling State

CHEN Liang, LIU Rong-zhong, GUO Rui, WU Jun-an, YANG Yong-liang, XING Bo-yang, GAO Ke, ZHAO Bo-bo

2018, 38(4): 338-346. doi:10.15918/j.tbit1001-0645.2018.04.002

Abstract(1359) PDF(734)

Abstract:
In order to investigate the aerodynamic characteristics of the hedgehopping projectile under the condition of high-speed rolling, comparative experimental investigations using wind tunnel tests were implemented first at static and freely rolling states. Based on this, both numerical technique and approximate analytical method were further employed to quantitatively analyze the influence of such a high-speed rolling state on aerodynamic parameters under various Mach numbers. Corresponding variation laws of the balance rotation speeds with respect to the empennage geometries were obtained as well. Main results indicate the following:the balance rotation speed rises with a descending gradient and an increasing Mach number; under a fixed Mach number, the increasing attack angle can lead to a non-linear decrease for balance rotation speed; all increasing root tip ratio, twist rate and sweepback enable a higher balance rotation speed; the aerodynamic characteristics in high-speed rolling states are distinctly different from those of the static case; besides the larger yawing moment, the lower pitching moment and the forward shift of pressure center are also caused, both of which are adverse to the flight stability of empennage projectile.

Coupling Dynamics Simulation Analysis for Typical Membrane Space Structures

RONG Ji-li, LIU Zhi-chao, XIN Peng-fei, XIANG Da-lin, WU Zhi-pei

2018, 38(4): 347-352,358. doi:10.15918/j.tbit1001-0645.2018.04.003

Abstract(1021) PDF(667)

Abstract:
A dynamics simulation of the motion process of typical membrane space structures was made, and the dynamic response in the motion process of membrane space structures was solved by the finite element method to analyze the configuration transformation and the stress distribution in the deployable process. The motion process and the deployment stability of membrane space structures was studied by analyzing the system kinetic energy change of membrane space structures. The finite element models of typical membrane space structures, which included self-collision, rectangle deployment and inflatable balloon extension, were established by SAMCEF Mecano and then the numerical simulation based on coupling method was completed by defining the self-contact of membrane structures and the contact between membrane structures and flexible structures. The simulation results show that coupling dynamic simulation of typical membrane space structures is reliable by using SAMCEF Mecano. The dynamic properties are effected by different motion modes and the deployment stability is better when deployment rate is lower.

Study on Damage Characteristics of Different Jets Based on SPH Method

GAO Ben-bing, YIN Jian-ping, CHEN Jie, WANG Zhi-jun

2018, 38(4): 353-358. doi:10.15918/j.tbit1001-0645.2018.04.004

Abstract(943) PDF(848)

Abstract:
In order to study the damage performance of different jets, the AUTODYN finite element software was used, and the smoothed particle hydrodynamics (SPH) method was adopted, to simulate the formation of jets and penetrating targets of different jets by copper, PTFE and PTFE-Cu materials, and experiments were carried out.The results show that the liner of Cu material form a condensed jet under the effect of detonation wave, while PTFE and PTFE-Cu liner form scattering particle jets. The processes of three kinds of jets penetrating the target plate show that the copper jet head has the lowest speed, deepest penetration depth, and the smallest openings; the head speed of PTFE jet is the highest, the penetration depth is the shallowest and the opening is intermediate. The head speed and penetration depth of the PTFE-Cu jet are intermediate and the openings are the largest. PTFE-Cu jet overcomes the shortcomings of penetration performance of PTFE jet, and its ability of opening is higher than that of the copper jet.

Experimental Research on Several Typical Blasting Vibration-Controlling Technologies

SUN Cui-yuan, XUE Li, MENG Hai-li, FU Tian-jie, KANG Yong-quan

2018, 38(4): 359-363,370. doi:10.15918/j.tbit1001-0645.2018.04.005

Abstract(971) PDF(535)

Abstract:
To effectively control the blasting seismic effect produced during blasting construction, different vibration reduction tests of some typical blasting vibration controlling technologies, including electronic detonator initiating, damping hole method, air cushion method and different initiating directions, were carried out. The change law of typical vibration parameters such as particle vibration velocity, vibration reduction ratio and vibration attenuation coefficient were obtained. Results show that these vibration reduction technologies can produce a certain damping effect under corresponding conditions. In the actual engineering blasting construction, geological conditions and surrounding environmental factors should be considered and the appropriate blasting vibration controlling technology should be chosen.

Dynamic Response Calculation Method for Multi-Shell Structure Completely Filled with Liquid Under UNDEX

LIU Guo-zhen, WANG Jun, LIU Jian-hu, CHEN Hui, ZHAO Yan-jie

2018, 38(4): 364-370. doi:10.15918/j.tbit1001-0645.2018.04.006

Abstract(937) PDF(746)

Abstract:
The fluid-filled multi-shell structure design is mostly used in submarines. The multi-shell structure consists of light shell and multi pressure shells. When it is exposed to attack by underwater weapons, the mechanism of transmission gets so complex that it has been a troublesome problem for a long time. In this paper, a numerical method was developed to solve the problem. The second-order doubly asymptotic approximations (DAA2) was used to analyze the external fluid-structure interaction (FSI) effect for the outer fluid field with the outer plates and cavitation acoustic finite element (CAFE) was used to model the internal FSI effect. Results obtained using this method showed good agreement with results of 3D fluid-filled spherical shell shock problem. Last, the method was validated by a fluid-filled multi-shell structure test. The velocity, acceleration and shock environment were compared with the test data. The research results show that the numerical method is accurate and have verified the effectiveness of the method.

Influence of Winding Angle Error of Artillery Rifling on the Positioning Accuracy of Air-Burst Fuze and Its Compensation

LI Hao-jie, WANG Wei-qiang, LI Chang-sheng, YANG Yu-xin

2018, 38(4): 371-375. doi:10.15918/j.tbit1001-0645.2018.04.007

Abstract(1079) PDF(480)

Abstract:
In order to reduce the distancing error of air-burst fuze and improve the accuracy of air-burst, the influence of machining error of the artillery rifling angle on the velocity accuracy of air-burst fuze was analyzed. The solution to compensating for the error of rifling angle was put forward. The data shows that the error of the rifling angle has a great influence on the accuracy of the velocity measurement. When the error is 9', it will cause about 1.75% of the velocity error, which will bring about the deviation of the accuracy. The compensation scheme of the rifling angle error based on the fuze setter was given. The experiment shows that the rifling error compensation scheme of the fuze setter can reduce the velocity error to about 0.2%, which can effectively reduce the fuze velocity error, improve the accuracy of air-burst fuze, and provide reference for the auto speed-testing fuze design.

Scale Adaptive and Anti-Occlusion Arithmetic for Moving Object Tracking

LIU Fu-xiang, QI He, JI Rui-jing, SHI Xiao-jun

2018, 38(4): 376-380. doi:10.15918/j.tbit1001-0645.2018.04.008

Abstract(1143) PDF(569)

Abstract:
In order to solve the problems during the target tracking process such as scale change, occlusion and tracking drift, an integrated tracking and detection algorithm was proposed, to which was added the scale change update mechanism based on the minimum mean square error (MOSSE) of the output, and the latest position and the optimal size of the target was calculated through the relevant calculation. The analysis of the tracking experiments of 51 test video sets on Benchmark demonstrates that the proposed algorithm performs better than traditional algorithm in terms of scale variation and occlusion resistance.

Research on Real-Time Haze Removal Algorithm for Marine Video

SHEN He-long, YIN Yong, XIA Gui-lin, TANG Huang

2018, 38(4): 381-386. doi:10.15918/j.tbit1001-0645.2018.04.009

Abstract(1055) PDF(683)

Abstract:
In order to improve ship navigation safety in fog,a real-time haze removal algorithm was proposed for marine surveillance video. For establishing fog degraded physical model,an inequality scaling theory was preliminarily used to estimate transmission and the global atmosphere for every frame of marine surveillance video. Then the haze-removal surveillance video was recovered based on the physical model. Finally,according to the marine surveillance video with large sky and sea areas,the parameters of the algorithm were estimated based on the factors of navigation target details and image contrast. The experiment results show that the algorithm can remove the haze in real-time speed,recover the marine targets' details and improve the image contrast. So,it proves that this algorithm can well solve the problem of real-time haze removal for marine surveillance video.

Detection of Ships in Harbor Based on Ship Head Feature Extraction and Contour Localization

WU Fei, WANG Bo, ZHOU Zhi-qiang, LI Sun

2018, 38(4): 387-392. doi:10.15918/j.tbit1001-0645.2018.04.010

Abstract(1005) PDF(868)

Abstract:
In this paper,a new method was proposed to detect inshore ships in high-resolution optical remote sensing images.Firstly,suspected ship head targets,been transformed into the polar coordinate system,were classified with support vector machine(SVM)to obtain head positions and directions of candidate ships.Secondly,the ship direction was refined by utilizing the line segments information around the ship.At last,the ship body was detected using grayscale and edge information in order to finally confirm this ship target.Experiment results show that the proposed method can accurately and robustly detect inshore ships.

Driver Face Detection Based on Deformable Part-Based Model

ZHAO Meng, ZHANG He, CAO Mao-yong, BAI Pei-rui, WANG Yang, PEI Ming-tao

2018, 38(4): 393-397. doi:10.15918/j.tbit1001-0645.2018.04.011

Abstract(1029) PDF(948)

Abstract:
To solve the problem of detecting driver faces from cabs images taken by traffic cameras,a driver face detection method was proposed based on deformable part-based model,overcoming the condition influence such as dim light,occlusion and low resolution in cabs.Firstly,extracting aggregate channel features (local binary pattern and histogram of oriented gradient),the candidate faces were obtained.Then,considering the relative settled position between the license plate and driver face,the driver face and plate were taken as two deformable parts of a face-plate couple based on the concept of deformable part-based model,and the ubiety of two parts was used to determine the position of the candidate face.Experimental results show that the proposed method can improve the detection accuracy and overall performance,effectively filter out the false face alarm,and the recall rate is less affected.

Non-Smooth PID Controller of a Small Floating Satellite Antenna in Sea

CAO Hai-qing, YAO Zhi-ying

2018, 38(4): 398-404. doi:10.15918/j.tbit1001-0645.2018.04.012

Abstract(784) PDF(456)

Abstract:
A novel non-smooth controller of the second order control system with a disturbance was proposed to control the attitude of a small floating satellite antenna in sea. Aiming at the standard second order integral system with a bounded disturbance,a novel non-smooth controller with a better rapidity,stability and strong disturbance rejection was studied. Several works were carried out including the stability proving,the strong disturbance rejection validating,sea disturbance properties analyzing,the models developing,and the disturbance rejection ability analyzing with different disturbances. Finally,a non-smooth PID azimuth controller of a small floating antenna was constructed based on the novel non-smooth controller to control the antenna's azimuth. Simulation and part experiment results validate that,the non-smooth PID controller of the small floating satellite antenna can quickly and steadily control the antenna's azimuth,and well reject the disturbances in sea to ensure a communication quality between the antenna and the target satellite.

FU Kai, XIA Jing-bo, WEI Ze-kun, JIA Yan-qing

2018, 38(4): 405-411. doi:10.15918/j.tbit1001-0645.2018.04.013

Abstract(1018) PDF(500)

Abstract:
A method of similarity measurement between cloud models was proposed based on mutual membership degree to solve the problems existing in current approaches,such as high consumption,unstable conclusion and limited applicability.Firstly,the membership degree of cloud models was defined with the ratio of common cloud area to itself cloud area according to expectation curve.Then,the similarity between cloud models was calculated with the mutual membership degree.Finally,the calculation formula and properties of similarity were produced,considering the calculation of the area with different intersection points and half cloud.Simulation results show that the proposed method can achieve rational similarity measurement between cloud models with high accuracy and low consumption in different situations.And the effectiveness of the method was further verified based on cloud model with an evaluation example.

A Rapid Ancient Architecture Modeling Method Facing the Gesture Interaction

REN Pu, ZHOU Ming-quan, FAN Ya-chun, QIAN Lu, SHUI Wu-yang

2018, 38(4): 412-416,436. doi:10.15918/j.tbit1001-0645.2018.04.014

Abstract(1067) PDF(627)

Abstract:
With the rapid development of VR industry,the non-contact gesture interactive application is increasingly common. In this paper,a modeling method with Leap Motion was proposed for rapid 3D VR scene developing of ancient architecture. Firstly,hand-motion data were captured with Leap Motion to implement the real time mapping,interactive controlling and editing of physical and 3D space. Secondly,a probabilistic model based recommending method was proposed for building components of ancient architecture. By designing a Bayesian network,the relationships between different components were calculated by probabilistic inference. Finally,several functions were implemented for rapid developing of ancient architecture scene,including returning the recommending results to user in real time,choosing corresponding components by gesture and optimizing the positions in the 3D space directly. Experimental results show that the method can take use of the 3D space information more effectively than traditional 2D style,and much more intuitive,convenient and efficient.

Preparation and Performance of Waterborne Polyurethane with Different Particle Size

CHAI Chun-peng, MA Yi-fei

2018, 38(4): 417-422. doi:10.15918/j.tbit1001-0645.2018.04.015

Abstract(992) PDF(638)

Abstract:
Carboxylic waterborne polyurethanes with different particle size and particle size distribution were prepared by two kinds of emulsification with isophorone diisocyanate(IPDI),poly(1,6-hexanediol/neopentyl glycol-alt-adipic acid) (PHNA),1,4-butanediol (BDO) and dimethylol propionic acid (DMPA) as the hydrophilic chain extending agent. The particle size and particle size distribution were measured by dynamic laser scattering method,and the stability,water absorption,tensile strength,elongation at break and gloss were determined successively. Results show that,the particle size range is from 40 nm to 340 nm,the particle size distribution (PDI) range is from 0.07 to 0.26,and different DMPA content and emulsification can lead to different partical size and PDI;among the WPUs,the highest tensile strength is 49.62 MPa with a 922% elongation at break,the least water absorption is 5.25%,and the top gloss is 87.8°;the partical size and PDI have an important influence on water absorption,tensile strength and gloss,but little on the elongation at break.

Fe-Based Coatings on Gun Steel Surface Deposited by PTA and Their Erosion Behavior

MEN Xiang-dong, TAO Feng-he, GAN Lin, ZHAO Fang, DI Chang-chun, LIU Xue-jie

2018, 38(4): 423-429. doi:10.15918/j.tbit1001-0645.2018.04.016

Abstract(1019) PDF(747)

Abstract:
Fe-based erosion resistant coatings A and B were prepared by plasma surfacing on the surface of gun steel.The microstructure and elements of the coatings were analyzed by X-ray diffraction,scanning electron microscopy and energy dispersive spectrometer.The hardness of the coating was measured by Vickers hardness tester,and the erosion resistance of the coating was tested by high speed heat flow generating device.The results show that both Fe-based coatings have good metallurgical bonding with the substrate.Coating A is com posed of Fe3Ni2,(Cr,Fe)7C3 and Fe-Cr solid solution.Coating B is composed of Cr3Ni2,Fe0.64Ni0.36,Fe7C3,Fe-Cr solid solution.After 40 tests of high-speed heat flow's erosion,the erosion behavior of the coatings was observed under scanning electron microscopy.Results show that,the erosion process of Coating A is extended from "intergranular erosion",to "crystallization erosion",then to "full crystal erosion".Coating B shows no obvious erosion behavior under scanning electron microscopy,but has produced transcrystalline cracks in the hot and cold cycle process.The two coatings have significantly enhanced the erosion resistance compared with the gun steel.

Optimal Selection of Energy Saving Program Based on Stackelberg Equilibrium

YANG Tian-jian, SONG Jing-xiu, PANG Bo-wen

2018, 38(4): 430-436. doi:10.15918/j.tbit1001-0645.2018.04.017

Abstract(748) PDF(558)

Abstract:
The energy saving service industry is developing rapidly and this paper discusses the choices for enterprise energy-saving because the government sets a threshold value about energy saving and adopts the subsidy policy to encourage enterprises to save energy. Given the scenario of subsidies, a profit-maximizing model and a Stackelberg game model were set respectively to determine the optimal energy saving and the benefit-sharing proportion. The effects of the choice of energy saving under different subsidies were analyzed. The results indicate that, considering the government's subsidies, the company will change the original energy-saving way, and tend to choose outsourcing to save energy, which is conducive to the development of energy-saving service industry.

Principal Bundle Structure of Statistical Manifolds

SUN Hua-fei, ZHANG Tong, HAN Xi-wu, LI Di-dong

2018, 38(4): 437-440. doi:10.15918/j.tbit1001-0645.2018.04.018

Abstract(1165) PDF(513)

Abstract:
The concept of principal bundles was introduced on statistical manifolds.First,some basic knowledge of principal bundles on manifold was presented.Then the α structure of frame bundles was studied.Finally,the presented methods were used to calculate the manifold of bivariate normal distributions.

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