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2015 Vol. 41, No. 12

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Volume 41 Issue122015
2015 Year 41 Volume 12 Issue E-journal
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Acoustic emission beamforming method for localizing rotor-stator rubbing fault
HE Tian, YE Wu, YU Haisheng, LIU Wenyang, LIU Xi
2015, 41(12): 2191-2197. doi: 10.13700/j.bh.1001-5965.2014.0828
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One of the challenges restricted rubbing quantitative diagnosis is that vibration method cannot be effective applied to rubbing fault localization. Therefore, an acoustic emission (AE) beamforming array was presented to localize rotor-stator rubbing fault of rotating machinery. Firstly, finite element simulation model of rubbing AE was established based on mechanical model of rotor-stator rubbing and the structure of rotor test-bed, which can be used to simulate AE signals and study characteristics of simulating signals and AE wave propagation. Then rubbing localization performances of AE beamforming with typical arrays, such as line array, crossed array and circular array, were studied based on simulation AE signals and propagation characteristics of rubbing AE, and that the line array was the most appropriate for rubbing localization. Aiming to the shortage of line array, the improved sensor array and localization scheme were approached. Finally, the proposed localizing method of rubbing fault was verified by experiments. The results show that AE beamforming method can achieve accurate localization of rubbing fault by choosing the right sensor array and suitable sensor arrangement.
Failure mechanism consistency identification based on acceleration coefficient constant principle
XI Wenjun, WANG Haowei, WANG Ruiqi
2015, 41(12): 2198-2204. doi: 10.13700/j.bh.1001-5965.2014.0815
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To solve the problem that it is hard to identify failure mechanism consistency in accelerated degradation test, taking a Gamma degradation model as research object, an identification method of failure mechanism consistency based on acceleration coefficient constant principle was proposed. The theory of identifying failure mechanism consistency was firstly explained, and then the acceleration coefficient constant principle was introduced to deduce the changing rule for parameters of Gamma process under different stress levels. The method based on t statistic was used to test the consistency of parameter estimates, so that whether the failure mechanism of product remains consistent or not can be identified. The proposed method is validated through simulation tests and case study, and the research conclusion indicates that the proposed method has a good engineering applicability.
Aircraft fire detection method based on CO2 concentration monitoring
ZHAO Jianhua, FANG Lili
2015, 41(12): 2205-2210. doi: 10.13700/j.bh.1001-5965.2015.0062
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High false alarm of heat detection and smoke detection used in aircraft is an existed question for aircraft fire detecting. The production rule of gaseous combustion products in fires was analyzed, and CO2 was put forward as parameter of fire detection. Through accurate monitoring of CO2 concentration in the environment, the aircraft fire detection was realized. Considering the particularity of environmental condition on aircraft, non-dispersion infrared (NDIR)was used to resolve the challenge of temperature compensation in aircraft fire detection. According to the relationship among the measured voltage of aircraft fire detector, environment temperature and reference voltage, temperature compensating model for aircraft fire detector was established based on partial least squares (PLS) approach. And model for CO2 concentration calculating had built by using PLS method, which was based on correlation between measured voltage of aircraft fire detector and CO2 concentration. With the calculated concentration of CO2, an alarm algorithm for aircraft fire detector was presented then, which provided a new fire detection method for aircraft.
Method for determining initial position of dead reckoning system of underwater vehicle
ZHANG Yanshun, GUO Yajing, HUANG Xiaojuan, LI Chunyu, WANG Zhanqing
2015, 41(12): 2211-2216. doi: 10.13700/j.bh.1001-5965.2014.0785
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According to the characteristics of underwater navigation sensors, the method for determining the initial position based on dead reckoning (DR) trajectory translation strategy in the initial period of position was proposed to improve the accuracy of the initial position of DR system. This method combined the features of DR system and hydroacoustic navigation system, and got the optimal trajectory under the constraints of certain movement trends by translating DR trajectory to calculate the initial position. One real sea trial data was used to analyze this method. The results show that the position error of this method is 60.2% and 77.2% of the error of the average method and the least squares fitting method. The application of this method can reduce the position error of DR system and improve the stability of DR/hydroacoustic integrated navigation system.
Smart meter lifetime evaluation based on multi-stress acceleration test method
ZHA Guoqing, HUANG Xiaokai, KANG Rui
2015, 41(12): 2217-2224. doi: 10.13700/j.bh.1001-5965.2014.0788
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How to accurately analyze and assess reliability and life of smart meters under the multi-stress and multi-parameter condition is a very hot research topic currently. Firstly, the performance of smart meter under conditions of temperature, humidity, electrical stress, vibration and magnetic field were analyzed, and the key performance parameters and sensitive stress were extracted based on failure mechanism analysis. Secondly, the limiting conditions of key performance parameters were explored through enhancement experiment. Finally, an acceleration lifetime experiment program according to the result of enhancement experiment was designed to obtain the key performance degradation data with integrated testing system and establish the degradation trace model, analyze the multi-stress acceleration model, and eventually comprehensively evaluate the smart meter reliability and life. The proposed methodology of evaluating smart meter reliability and life with enhancement experiment and acceleration experiment, the research thought and conclusions can provide theoretical support for the improvement of smart meter reliability and life.
Evaluation method for accelerated degradation testing with interval analysis
LIU Le, LI Xiaoyang, JIANG Tongmin
2015, 41(12): 2225-2231. doi: 10.13700/j.bh.1001-5965.2014.0790
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Traditional evaluation methods of accelerated degradation testing (ADT) are based on precise degradation data to conduct reliability and lifetime assessment. However, with interfere of the uncertainties from human factors, the test data can be imprecise represented by interval rather than precise data. Under this consideration, an interval analysis method for ADT evaluation was proposed based on Wiener process, which included possibility and necessity models. Interval regression method was firstly used to transfer the problems of modeling interval degradation data under different accelerated stress levels into quadratic programming problems. The interval drift coefficients under different stress levels with possibility model and diffusion coefficient were obtained. Then the interval drift coefficients were extrapolated to normal stress condition with accelerated model under necessity model, and further to analyze the relationship between measurement uncertainty and reliability and lifetime evaluation results. Finally, the numerical study was used to present and verify the proposed methodology, and conduct uncertainty sensitivity analysis. The results show that both reliability and lifetime evaluation results are effected by epistemic uncertainty of measurement, and their correctness can be ensured with decreasing epistemic uncertainty.
Optimization design of approach and landing trajectory for variable configuration RLV with multi-control surfaces
HAO Xianwei, WANG Yong, YANG Ye, GUO Tao
2015, 41(12): 2232-2239. doi: 10.13700/j.bh.1001-5965.2014.0822
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To solve approach and landing problem of variable configuration reusable launch vehicle (RLV) with multi-control surfaces, a design method of approach and landing trajectory was proposed. The landing trajectory was divided into steep glide landing trajectory and flare landing trajectory. The controllable deflection limit of the aerodynamic surfaces and deep downturn quasi equilibrium equation constraints were considered and the steep glide landing trajectory optimization design was carried out. The RLV aerodynamic surface adjusting redundancy and variable configuration processes were considered, with constraint conditions of the gear down time, the flare normal overload and the grounding state, by the trajectory propagation based on the RLV dynamics equation, the optimal flare landing trajectory was designed and optimized. The steep glide landing trajectory and flare landing trajectory composed a complete approach and landing trajectory. Therefore, the designed approach and landing trajectory considered multi constraint conditions and improved the stability and safety of the landing process.
Gray target tracking algorithm based on edge information
ZHENG Haichao, MAO Xia, LIANG Xiaogeng
2015, 41(12): 2240-2249. doi: 10.13700/j.bh.1001-5965.2014.0827
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To precisely track the gray targets undergoing drastic changes in the image sequence, a new tracking algorithm based on edge information was proposed. Firstly, obtained by the two-concentric-circular-window operator, a nonlinear edge detection algorithm was proposed to get high quality edge information. Secondly, a novel method to construct feature space by synthesizing edge images was proposed in order to solve the problem that single edge feature space was not able to characterize the target thoroughly. The proposed method provided enough information to construct target model. Then, an approach to construct the target model with the kernel-based estimation method was proposed in constructed feature space. In target localization stage, the target position was preliminarily predicted by Kalman filter, and then the Mean Shift algorithm is utilized to locate the target in the region around the predicted position. Finally, a new dynamic model update strategy based on morphological operations was proposed. It can offer the proposed algorithm the ability to obtain precise target region and automatically adjust to the changing target size and target shape. Experimental results demonstrate that the proposed algorithm can perform well in image sequences where the targets undergo drastic changes. Meanwhile, the proposed algorithm can obtain the precise target region, and the track window can automatically adjust to the changing target size and target shape.
Modified wide temperature compensation method for analog TCXO
HAN Yanju, YANG Ke, ZHENG Hongyao
2015, 41(12): 2250-2255. doi: 10.13700/j.bh.1001-5965.2015.0003
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When the temperature frequency stability of the temperature compensated crystal oscillator (TCXO) is required better than ±1×10-6 in a wide temperature range, the rate of once success for the traditional compensation method is low. The compensation precision influences were carefully analyzed, and the reasons were drawn that the measurement method and the calculation model of the thermistors within the temperature compensation network caused the higher tolerance. So a modified wide temperature compensation method was provided. At first, the reference thermistors were measured on-line in the wide temperature range to obtain the practical data. Secondly, the thermistors for using were proportionally modeled according to the reference thermistors measurement data to acquire the resistance for each temperature. At last, the modeled thermistors were input into the temperature compensation program, and the genetic algorithm was used to compute the optimized network parameters. The contrast tests were carried out, and show that the thermistor values with new modeling method are closer to the test values than those with the traditional method, the compensation program is more flexible, and the rate of once success for temperature compensation is improved more than 90%.
Guidance law with impact angle constraints based on extended disturbance observer
ZHANG Jiao, YANG Xu, LIU Yuanxiang
2015, 41(12): 2256-2268. doi: 10.13700/j.bh.1001-5965.2015.0013
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Aimed at the requirement for intercepting maneuvering targets with impact angle constraint, based on the technology of extended disturbance observer (EDO), a novel finite-time convergence guidance law was presented. Considering the relative motion between missile and target, the time-varying uncertainty of missile velocity and the unknown target acceleration were regarded as the disturbance, which is estimated and compensated by EDO. The fast tracking differentiator was introduced to solve the immeasurability problem of the desired line of sight angle rate. Moreover, the domain of sliding mode capturability was introduced to the performance evaluation of guidance law. The simulation experiments of different interception scenarios and different forms of maneuvering target were carried out. The simulation results show that the proposed guidance law has good interception performance and robustness, and it is of less missile acceleration and higher guidance accuracy, which is more helpful for the realization in engineering.
Modeling method of bolted joints of aero-engine based on thin-layer element
YAO Xingyu, WANG Jianjun, ZHAI Xue
2015, 41(12): 2269-2279. doi: 10.13700/j.bh.1001-5965.2014.0796
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The bolted joints, which are commonly used in aero-engine structure, have important influences on dynamic characteristics of aero-engine. The thin-layer element method can simulate complex connection structure and maintain the structure integrity. Based on the thin-layer element method, the modeling principles of aero-engine bolted joints was studied and the influence law of material parameters of thin-layer element on bolted joints stiffness was researched. Then the material parameters of thin-layer element through theoretical derivation were determined. Finally it was applied to actual structure and compared with detailed finite elements model so as to verify the correctness and aspect of this method. The results indicate that the thin-layer element method can simulate aero-engine bolted joints excellently; the axial and bending stiffness are decided by axial elastic modulus of thin-layer element, and the shear stiffness is decided by the xy and xz plane shear modulus of thin-layer element; the material parameters of thin-layer element can be expressed by structural parameters of bolted joints.
Three-dimensional rolling path planning via dynamic fluid disturbance
YAO Peng, WANG Honglun, LIU Chang
2015, 41(12): 2280-2287. doi: 10.13700/j.bh.1001-5965.2014.0773
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Considering the existence of moving target, moving threat and emergent threat in complex environment, the method of dynamic fluid disturbance and the rolling optimization strategy were combined for the three-dimensional dynamic path planning of unmanned aerial vehicle (UAV). Based on the motion information of moving target and threat, the relative initial fluid was constructed. Then, the influence of obstacles or threats on the relative initial fluid was quantized by the disturbance matrix. The relative modified flow was then obtained by modulation. Then the actual streamline which was the planning path, was easily accomplished. By fully utilizing the real-time environmental information and considering the motion in the future, the method of dynamic fluid disturbance was utilized to plan local path in limited time-domain. And the objective function was built and the reactive parameter was obtained by rolling optimization to realize the online path planning. Finally, the effectiveness of the method in complex dynamic environment is indicated.
Modeling technology of radiation belt in LEO based on data gridding methods
CHANG Zheng, WANG Yongmei, TIAN Tian, ZHANG Xianguo
2015, 41(12): 2288-2295. doi: 10.13700/j.bh.1001-5965.2014.0799
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The energetic charged particle in the radiation belts of earth is the main environmental factor which can result in performance degradation and even failure of the material and device on spacecraft, so the accuracy of radiation belts model which is being used during design phase of spacecraft is very important to spacecraft performance of space mission and survivability. In the development of radiation belts model based on our own country's data from exploration of radiation belts, the gridding of discrete data is a fundamental task. The key facts of data from Chinese exploration of radiation belts were introduced, the goal and road-map of modeling were described, the application of interpolation in gridding of modeling of radiation belts in low-earth orbit(LEO) was discussed, and the significant errors were analysed. The result of interpolation indicates that in mainly interpolation methods, inverse distance weighting (IDW), natural neighbor and nearest neighbor are most suitable for engineering calculation, the particle flux which is inverted from data grid produced by IDW has the highest precision, and the result from IDW will be more accurate when IDW uses small exponent of distance.
Difference methods for two-dimensional space-time fractional dispersion equation
ZHANG Yinghan, YANG Xiaoyuan
2015, 41(12): 2296-2301. doi: 10.13700/j.bh.1001-5965.2014.0813
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The two-dimensional space-time fractional dispersion equation is obtained from the standard two-dimensional dispersion equation by replacing the first order time derivative by the Caputo fractional derivative, and the two second order space derivatives by the Riemann-Liouville fractional derivatives, respectively. Base on the shifted Grünwald finite difference approximation for the two space fractional derivatives, an implicit difference method and a practical alternate direction implicit difference method were proposed to approximate the fractional dispersion equation. The consistency, stability, and convergence of the two implicit difference methods were analyzed. By using mathematical induction method, it was proven that the two implicit difference methods were all unconditionally stable and convergent and the order of convergence were obtained. The convergence speed and computational complexity of the two implicit difference methods were compared. A numerical simulation for a space-time fractional dispersion equation with known exact solution was also presented, and correctness of the theoretical analysis was verified by the numerical results.
Adaptive control for two-spacecraft electromagnetic formation keeping
XU Zengwen, SHI Peng, ZHAO Yushan
2015, 41(12): 2302-2308. doi: 10.13700/j.bh.1001-5965.2014.0814
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Electromagnetic spacecraft formation flying is a new type of spacecraft formation using electromagnetic forces between spacecraft to control relative motion. Primary principles of the relative motion of a two-craft electromagnetic formation were discussed. Analytical solutions of control magnetic moments according to commanded control forces for the case of two-spacecraft electromagnetic formation were developed considering the energy consumption equilibrium. Nonlinear relative motion dynamic models for a two-spacecraft electromagnetic formation were derived based on polar coordinates. Parameter uncertainties of the equations because of the approximation of the electromagnetic model and unknown disturbed forces were analyzed. Nonlinear adaptive feedback control laws for formation keeping were then designed, and the closed-loop dynamic procedure of a two-spacecraft electromagnetic formation in a low earth circular orbit was simulated. Results indicate that the relative motion equations and the adaptive control laws are valid. The formation can effectively converge to desired states and the unknown parameters are estimated accurately. The simulations demonstrate that electromagnetic forces between spacecraft can be used to realize spacecraft formation keeping and the electromagnetic formation flying is feasible.
Robust visual saliency detection method for infrared small target
WANG Gang, CHEN Yongguang, YANG Suochang, GAO Min, DAI Yaping
2015, 41(12): 2309-2318. doi: 10.13700/j.bh.1001-5965.2014.0834
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As a key technique in automatic target detection, robust detection of small infrared target at low signal-to-noise ratio has received a lot of attentions. In order to detect infrared (IR) small targets efficaciously, the apparent characteristics and visual saliency of infrared small target were both analyzed. Thereafter, a robust saliency detection algorithm for infrared small target based on multiscale ordered contrast of image patch (MOCIP) was proposed. The cascaded MOCIP was developed to detect the saliency of infrared small target by suppressing the background and noise and enhancing the infrared small target in two consecutive steps. Consequently, the salient target can be detected with an adaptive threshold in the saliency map obtained by cascaded MOCIP. The robust saliency detection algorithm was presented in details and the efficacy was analyzed. Verification and comparison experiments of detecting the saliency of infrared small target were both conducted. All experiments results show that the proposed MOCIP method is effective and robust in overcoming the impact of noise and complex background and in detecting the saliency of infrared small target at low signal-to-noise (SNR) ratio.
Digital simulation on reusable liquid rocket engine availability
LIU Shijie, LIANG Guozhu
2015, 41(12): 2319-2327. doi: 10.13700/j.bh.1001-5965.2015.0006
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The reusable liquid rocket engine (RLRE), which can reduce the space launch cost, is one of the future spacecraft development directions. It is difficult to assess the RLRE availability for its complexity, differences of the component life model and other uncertain factors. As an example, the availability of space shuttle main engine (SSME) high-pressure fuel (hydrogen) Turbopump (HPFTP) was analyzed using Monte Carlo simulation technology based on the historical data of SSME. The method, taking into account the impact of early maintenance on the later maintenance, did not involve the life distribution model of components, and can reasonably simulate the process of system failure occurrence. The results show that under incomplete maintenance the mean best reasonable preventive maintenance time of HPFTP is 6 340 s, it can be reused theoretically 12 times for satisfying the mission requirement of the space shuttle, and the corresponding mean best availability is 0.285. The availability of HPFTP is low due to its severe working process. This study provides a reference for studying the aerospace propulsion reusability.
Group delay calibration method for GNSS signal simulator channel
LI Shiguang, KOU Yanhong, YANG Jun, WANG Wei
2015, 41(12): 2328-2334. doi: 10.13700/j.bh.1001-5965.2015.0007
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Two kinds of traditional group delay calibration methods for global navigation satellite system (GNSS) signal simulator channels have been reported so far,which are phase transition point method and correlation peak method. Both of them measure the group delay in a special simulation scenario with zero or fixed pseudorange, and the measurements under non-ideal channel transmission characteristics are biased estimates of the group delay. A group delay calibration method for simulator channel based on closed-loop pseudorange measurement was proposed, and the corresponding group delay calibration system for GNSS signal simulator channels were designed. Firstly, the navigation signal and one pulse per second (1 PPS) signal outputted by the simulator in normal constellation dynamic scenariowere recorded simultaneously by a high-speed direct radio freqency (RF) sampling and storage system. Secondly, the navigation signal was captured and tracked by a software receiver, and the 1 PPS signal rising edge was determined by cubic spline interpolation and used as the pseudorange measurement epoch. Then the group delay can be obtained by data comparison between the software receiver-measured pseudorange and the simulator-recorded true pseudorange. Finally, the group delays of two different commercialsimulators were calibrated employing all the above methods. The experimental results show that the proposed method is effectively feasible and the measurement uncertainty reaches below 0.7 ns.
Analysis of image processing model based on pixels of solitary waves
ZHU Zimin, LIU Rongqiang, LIU Fenfen, CAO Youwei
2015, 41(12): 2335-2339. doi: 10.13700/j.bh.1001-5965.2015.0009
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Through the study on nonlinear effect of digital image pixel grid, the one-dimensional and two-dimensional time evolution equations model of nonlinear effect between pixels were established, the analysis of the equation model shows that the image was discrete in space, but on the structure of mutual information was a continuous differential difference equations, and the equation had analytic solitary wave solutions. The model was used to study the interaction of image pixels between two solitary waves, pixel solitary wave of two solitary wave solutions were given, and used the interaction of solitary waves of the pixel to study the performance of model, it was found that pixel solitary wave can still maintain their properties unchanged after the interaction, so pixel itself can be replaced by pixel solitary wave. To study the interaction situation of pixel solitary wave, it was found that pixel solitary wave amplitude was nonlinear superposition of the two, so it could be used as the result of the influence. The phase change of pixel solitary wave can map for direction and provide direction information of the image. The experiment result shows that the model can be used in image filtering, although the smoothness is not optimal, image details retain more.
Warship spare parts allotment optimization method under mixed-constraints
CAI Zhiming, JIN Jiashan, CHEN Yanqiao
2015, 41(12): 2340-2347. doi: 10.13700/j.bh.1001-5965.2015.0011
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The quantitative or qualitative constraints of the warship spare parts allotment optimization problems are mainly focused on by the group of international and domestic academics, the mixed problems which include all of them are relatively less in the previous papers. Firstly, the warship carrying spare parts at the mission preparation before sailing was taken as a research background, the warship support cost, warehouse space, carrying ability and maintainability were adopted as mixed-constraints conditions, an optimized model of the warship spare support probability was built, the method of scoring by experts, normalization and marginal algorithm were applied to build the warship spare parts allotment optimization model and process optimization. Secondly, the model algorithms and system resource constrained factors were being confirmed and dynamically updated. Finally, in the given example, the calculated result was analyzed, and the feasibility of the proposed method was verified.
Dynamic symbolic execution approach based on tabu search
CAI Jun, ZOU Peng, MA Jinxin, HE Jun
2015, 41(12): 2348-2355. doi: 10.13700/j.bh.1001-5965.2015.0164
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Software vulnerabilities are one of the root causes of network security problem, and software vulnerability detection is currently a hot topic in the field of network security. Dynamic symbolic execution is one of the most studied approaches for vulnerability detection recently. Aimed at the problem that existing dynamic symbolic approaches produced a large number of duplicate or near-duplicate test cases, we proposed a novel dynamic symbolic execution approach based on tabu search, and implemented a corresponding tool named SwordSE. The proposed approach took advantage of the tabu search algorithm's ability of global optimization, it can do optimized seed selection by establishing an evaluation function, and can avoid duplicate path search by establishing a tabu list. Experiment results show that SwordSE's path search efficiency is significantly better than those of existing tools, and has detected four zero-day vulnerabilities until now.
Breakup characteristics of liquid jet in supersonic cross flow
LI Feng, LYU Fuguo, LUO Weidong, ZHAO Kai, WANG Changsheng, XIONG Yiwei
2015, 41(12): 2356-2362. doi: 10.13700/j.bh.1001-5965.2014.0792
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In order to study the atomization mixing characteristics of liquid fuel in scramjet combustor as well as determine the key factors influencing the atomization so as to realize efficient combustion, the flow field structure of the shock wave, jet penetration and induced bow shock strength of liquid jet aviation kerosene RP-3 and water in supersonic flow were experimentally studied respectively by mainly using the schlieren method,assisted with planar laser induced fluorescence (PLIF) technology and particle diameter measurement technology in supersonic combustion cold spray experiment platform. And jet atomization mixing characteristics were mathematically analyzed. It is demonstrated that defined dimensionless parameters could qualitative analyze variation trend associated with both two kinds of liquid jet in supersonic cross flow, and the conclusion is consistent with the experimental result. Within the scope of the dynamic pressure ratio of 1.0-3.3, the jet penetration and induced bow shock strength increases with the increase of dynamic pressure ratio and jet velocity. Surface tension and viscosity have important effects on the supersonic jet mixing.
Analysis of all time-delay stability for biological systems using symbolic computation methods
LIU Jun, NIU Wei
2015, 41(12): 2363-2369. doi: 10.13700/j.bh.1001-5965.2014.0794
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All time-delay stability for biological systems shows that the time-delay system possess good reliability, so this issue has always been the highlight of the scholars research. However, researchers usually adopt the traditional mathematical methods or numerical calculation methods. Based on Hurwitz criterion and polynomial complete discriminant system, a sufficient and necessary algebraic criterion of all time-delay stability for nonlinear biological systems with parameters was introduced. By using symbolic computation methods, such as the methods of Grbner basis,triangular decomposition and real solution classification, a systematic and algorithmic approach for automatically analyzing all time-delay stability of biological systems with parameters was proposed. All the computations in our approach are all exact, which may help biologists and engineers to perform algebraic analysis for certain biological models. The successful experiments on the all time-delay stability analysis of several biological models, such as time delayed Lotka-Volterra systems and SIR epidemic models with time delay, showed the feasibility of our algebraic approach and also the superiority of symbolic computation methods compared with traditional mathematic methods.
Comprehensive evaluation on influence degree of source data for civil aircraft technical publication
CHEN Jie, LIU Hu, PENG Heping, SONG Yuqi
2015, 41(12): 2370-2376. doi: 10.13700/j.bh.1001-5965.2014.0816
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The influence degree analysis of source data mainly depends on manual work in the current maintenance of civil aircraft technical publications. This process forcefully depends on professional ability of staff, so it can't guarantee the reasonable priority of source data in implementation of maintenance process, impacting the normal use of civil aircraft easily. Based on analysis for main professional process of technical publications business, the influence degree model of source data based on analytic hierarchy process (AHP)used comprehensive evaluation method, established the evaluation index system for influence degree model and determined weight coefficients, and then it obtained value and grade of numerical influence degree, which can be a basis of priority judgment for changes of source data. This model makes the influence of source data quantifiable and standardized, and keeps influence analysis of source data free from personnel, decreasing human error in professional activity. The analysis for an example shows that the method proposed can reasonably judge the priority of maintaining source data and can be used in conjunction with the system of technical publications preparation and management, which has important value in engineering applications.
Research and implementation of MBD dataset definition based on association rules
WANG Hong, YU Yong, YIN Pu, ZHAO Gang, WANG Wei
2015, 41(12): 2377-2383. doi: 10.13700/j.bh.1001-5965.2014.0819
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A model based definition (MBD) dataset definition method based on the association rules was proposed to meet the requirement of product full three dimensional digitalization development. Firstly, this method thoroughly decomposed all the design, manufacturing and inspection standards used in the product's development process. All the standard operation method, order and requirement (engineering note items) of all the standards were uniformly encoded, managed and released by the computer. Secondly, the association rule was utilized to mine the MBD dataset's creation history records, by which the potential association relationships among engineering note items can be revealed. Finally, based on the association relationships among engineering note items, the proper engineering note items can be pushed out as needed in the process of MBD creation. The proposed method uses the association rule theory in data mining as its basis, exploiting the helpful knowledge and experiences obtained from MBD dataset's creation history, thus is capable of improving the MBD dataset's creation efficiency by engineering note items recommendation.
Distributed adaptive iterative learning control for multiple robot manipulators
SUN Jipeng, MENG Deyuan, DU Mingjun, ZUO Zongyu
2015, 41(12): 2384-2390. doi: 10.13700/j.bh.1001-5965.2014.0831
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A hybrid adaptive and iterative learning method was proposed to obtain distributed control protocols for multiple manipulator systems with undirected interaction topology to achieve consensus tracking of the specified desired reference trajectory. By introducing an appropriate adaptive iterative learning parameter, the proposed adaptive iterative learning control (AILC) protocol can overcome the effects of disturbances and model uncertainties of manipulators, where the AILC law of each manipulator needs only the relative information between it and its nearest neighbors. Moreover, it is shown that all manipulators can be rendered to achieve the perfect tracking of the desired reference trajectory though its information can be accessed by only a portion of manipulators, where the boundedness of both the tracking error and the control input can be simultaneously guaranteed. In addition, the Lyapunov analysis method is employed to validate the obtained results, and the effectiveness of the proposed AILC protocol is illustrated through an example.
Design method of a PD-based temperature control system for laser diode
CHEN Xi, QUAN Wei
2015, 41(12): 2391-2396. doi: 10.13700/j.bh.1001-5965.2015.0001
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Semiconductor lasers are widely used as pump and probe laser light source in atomic physics and quantum science equipment researches. The characteristics of the laser diodes, such as threshold current, wavelength, output power, lifetime, are temperature dependent, therefore it is vitally important to control the temperature of semiconductor lasers. Based on the relation between laser temperature and the output power, a photodiode (PD) based laser temperature control system was proposed. The light power of lasers can be acquired by the monitor photodiode in the laser package and then the laser junction temperature can be obtained by the relation between the power and the temperature. A double close loop control system was designed using the photodiode integrated with the temperature sensor and the thermoelectric coolers as the actuator. The test result indicates that the long-term stability of the photodiode-baserd laser diode temperature control system can realize better than ±5 mK and meet the requirement of semiconductor lasers for the experiment and study of atomic physics.

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