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    01 December 2018, Volume 23 Issue 6 Previous Issue    Next Issue

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    Relative Attitude Dynamics and Control of Spacecraft Formation Flying Considering Flexible Panels
    YU Zhangwei (余章卫), CAI Guoping (蔡国平)
    2018, 23 (6):  721-729.  doi: 10.1007/s12204-018-1998-6
    Abstract ( 380 )  
    As a key technology for orbital applications, researches on spacecraft formation flying (SFF) attract more attention. However, most of existing researches about dynamics and control of SFF focus on rigid spacecrafts without considering the effect of flexible attachments (such as flexible panels). In this paper, relative attitude dynamics and active control of SFF for a flexible spacecraft (follower spacecraft) and a rigid spacecraft (target spacecraft) are investigated. Firstly, a dynamic model of the flexible spacecraft is established by the principle of angular momentum. Then, the equation of relative attitude dynamics between the flexible spacecraft and the rigid spacecraft is derived by the quaternion to represent the attitude relation of the two spacecrafts. Finally, an attitude feedback controller is designed for the SFF system, and its stability is proved by the Lyapunov stability theory. Simulation results indicate that the panel flexibility has an obvious influence on the dynamic behaviour of the system, the designed controller can effectively control the attitude of the two spacecrafts to achieve synchronization, and the elastic vibration of the panels may be suppressed simultaneously.
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    Experimental Study on Ship-Bank Interaction of Very Large Crude Carrier in Shallow Water
    LIU Han (刘晗), MA Ning (马宁), GU Xiechong (顾解忡)
    2018, 23 (6):  730-739.  doi: 10.1007/s12204-018-1999-5
    Abstract ( 338 )  
    In order to assess the influence of ship-bank interaction on ship manoeuvring motion, planar motion mechanism (PMM) tests on a scale model of the KRISO very large crude carrier (KVLCC2) are conducted in different water depths in circulating water channel (CWC). The asymmetric hydrodynamic derivatives are defined to characterize the bank effect, and they are measured through the straight towing test with varying lateral displacements. The linear and nonlinear hydrodynamic derivatives are determined from the test data of the Fourier integral and mathematical regression model. The rudder and heading angles required at equilibrium conditions in different ship-bank distances are calculated by the manoeuvring model. The directional stability with varying ship-bank distances is studied in terms of eigenvalue analysis. Analysis based on the test results shows that the KVLCC2 model ship appears inherently unstable for keeping course in deep and shallow water conditions. When the ship-bank distance decreases, the increasing ship-bank interaction can dramatically affect some parameters of the criteria for course keeping.
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    Design of Braunbeck Coil for Nuclear Magnetic Resonance Gyro Magnetic Field Excitation
    WANG Pei (王昢), LIU Hua (刘华), CHENG Xiang (程翔), ZHAO Wanliang (赵万良), LI Shaoliang (李绍良), CHENG Yuxiang (成宇翔)
    2018, 23 (6):  740-745.  doi: 10.1007/s12204-018-2000-3
    Abstract ( 385 )  
    For generating a uniform and steady magnetic field, Helmholtz coil is extensively used in nuclear magnetic resonance gyro (NMRG). Unfortunately, the volume of Helmholtz coil makes it inconvenient to miniaturize NMRG. This study introduces Braunbeck coil that can be used in magnetic field excitation system. Braunbeck coil can produce homogeneous magnetic field within a limit space, and occupy a small volume. In addition, this study presents mathematical expressions that can be used to calculate the area of uniform magnetic field. Experimental test verifies the effectiveness of the proposed design, and the results accord closely with the actual simulation.
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    Prototype Loading Tests on Full-Ring Segmental Lining of Rectangular Shield Tunnel
    ZHU Yeting (朱叶艇), ZHANG Zixin (张子新), HUANG Xin (黄昕), ZHANG Guanjun (张冠军)
    2018, 23 (6):  746-757.  doi: 10.1007/s12204-018-1979-9
    Abstract ( 260 )  
    A series of full-scale loading tests are performed for a prospective subway tunnel with a rectangular shape including two reliability tests: one stagger-jointed three-ring reliability test, and one ultimate failure test on a single ring. Comprehensive measuring programs are designed to record the deformation of both lining structure and joints and the stresses of concrete, bolts and reinforcements. Experimental results show that in both the single-ring and three-ring loading cases, the long sides of tunnel cross section bend inwards while the short sides of tunnel cross section bend outwards. The inner part of joints opens while the outer part of joints closes at places experiencing positive moment and vice versa. Joint’s rotational stiffness varies at different locations. Concrete cracking and crushing are the chief damage modes, and they are closely related to the distribution of bending moment. Stagger-jointed fabrication significantly increases the overall rigidity of lining system, which thereby greatly reduces the deformation of both concrete lining and joints in comparison with the single-ring case. It is shown that the routinely-used uniform rigidity model is conservative and the preliminary design can be optimized by applying an effective rigidity ratio (ERR) of 0.5.
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    Approach for Reliability Evaluation of Cross-Linked Polyethylene Under Combined Thermal and Vibration Stresses
    LIU Ji (刘骥), ZHANG Mingze (张明泽), CHEN Xin (陈昕), QI Pengshuai (齐朋帅)
    2018, 23 (6):  758-763.  doi: 10.1007/s12204-018-1980-3
    Abstract ( 271 )  
    Based on Wiener process model, a new approach for reliability evaluation of cross-linked polyethylene (XLPE) is proposed to improve the lifetime evaluation reliability of XLPE under multi-stressing conditions and study the failure probability distribution. In this paper, two accelerated aging tests are carried out under combined thermal and vibration conditions. The volume resistance degradation data of XLPE samples are tested with a 24 h interval under the accelerated stressing conditions at (130?C, 12 m/s2) and (150?C, 8.5m/s2), respectively. Nonlinear degradation data obtained from the experiment are transformed to linear intermediate-variable values using time scaling function, and then linearized degradation data are calculated and evaluated on the basis of linear Wiener process model. Considering traditional Arrhenius equation and inverse power criterion, parameters of the linear Wiener model are estimated according to the maximum likelihood function. The relationship curves on probability density and reliability are given, and the lifetime distribution of XLPE under different stressing conditions is also obtained for evaluating the reliability of XLPE insulation. Finally, the life expectancy of XLPE is 17.9 a under an allowance temperature of 90 ?C and an actual vibration acceleration of 0.5m/s2. The approach and results in this paper may be used for reliability assessment of high-voltage multiple samples or apparatuses.
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    Block Limit Analysis Method for Stability of Slopes During Earthquakes
    YIN Xiaojun (尹小军), WANG Lanmin (王兰民)
    2018, 23 (6):  764-769.  doi: 10.1007/s12204-018-1997-7
    Abstract ( 313 )  
    Based on the limit analysis upper bound method, a new mechanism of soil slope failure has been proposed which was consisted of plastic shear zone and rigid block zone. The different zones interface were regarded as discontinuity lines. Two sliding blocks of the slope were also incorporated horizontal seismic force and vertical gravity force. The velocities and forces were analyzed in two blocks, and the expression of velocity discontinuities was derived according to the principle of incompressibility. The external force done work for the blocks and the internal energy dissipated of the plastic shear zone and the velocity discontinuous were solved. The stability ratios were derived for the height of two-level slope with different rates to involve seismic and no seismic. The present stability ratios were compared to the previous study, which showed the superiority of the mechanism and the rationality of the analysis. The critical height of the slope can provide a theoretical basis for slope support and design.
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    Reliability Analysis of Aero-Engine Main Fuel System Based on GO Methodology
    ZHANG Sheng (张生), REN Chenhui (任晨辉), WAN Liyong (万里勇), YI Xiaojian (伊枭剑), DONG Haiping (董海平)
    2018, 23 (6):  770-775.  doi: 10.1007/s12204-018-1986-x
    Abstract ( 358 )  
    To improve the reliability of an aero-engine main fuel system, the quantitative and qualitative reliability analysis of the system is conducted based on goal oriented (GO) methodology. The quantitative reliability analysis results and the minimum cut sets of the fuel system are obtained, respectively. These results are compared with the results of the FTA (Fault Tree Analysis) method, and the comparison result shows GO method is rational and applicable. Therefore, it is feasible to apply the GO method in the reliability analysis of an aero-engine main fuel system.
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    Research on Nonlinear Dynamic Simulation and Fatigue Reliability Life Prediction for Synthesis Transmission System of Self-Propelled Gun
    YU Guibo (于贵波), CAO Lijun (曹立军), WANG Shuhai (王书海), MA Qiao (马乔)
    2018, 23 (6):  776-783.  doi: 10.1007/s12204-018-1996-8
    Abstract ( 433 )  
    Aiming to the puzzle that the inner load of nonlinear synthesis transmission system is difficult to obtain, a new kind of virtual prototype establishment and simulation method is put forward. The influence on nonlinear vibration with flexible rotor, bearing backlash is analyzed based on a virtual prototype. To validate the virtual prototype of nonlinear gear transmission system, the corresponding test platform is established. The consistency between simulation results and test results proves that the simulation results of the virtual prototype can be used to calculate the fatigue reliability life of key components. A new kind of fatigue reliability life prediction method of gear system considering multi-random parameter distribution is put forward based on the fatiguestatistic theory. Considering the periodicity of gear meshing, linear interpolation method is adopted to obtain the stress-time course of random load spectrum based on the gear’s complicated torque provided by virtual prototype. The gear’s P-Sa-Sm-N curved cluster can be simulated based on material’s P-S-N curve. The simulation process considers the parameter distributions of stress concentration coefficients, dimension coefficients and surface quality treatment coefficients, and settles the puzzle that traditional test methods cannot acquire the gear’s fatigue life of all reliability levels. This method can provide the distribution function and the interval of fatigue reliability life of gear’s danger region, and has a guide meaning for the gear maintenance periods determination and reliability evaluation.
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    Bivariate Constant-Stress Accelerated Degradation Model and Inference Based on the Inverse Gaussian Process
    DUAN Fengjun (段凤君), WANG Guanjun (王冠军)
    2018, 23 (6):  784-790.  doi: 10.1007/s12204-018-1984-z
    Abstract ( 372 )  
    Modern highly reliable products may have two or more quality characteristics (QCs) because of their complex structures and abundant functions. Relations between the QCs should be considered when assessing the reliability of these products. This paper conducts a Bayesian analysis for a bivariate constant-stress accelerated degradation model based on the inverse Gaussian (IG) process. We assume that the product considered has two QCs and each of the QCs is governed by an IG process. The relationship between the QCs is described by a Frank copula function. We also assume that the stress on the products affects not only the parameters of the IG processes, but also the parameter of the Frank copula function. The Bayesian MCMC method is developed to calculate the maximum likelihood estimators (MLE) of the model parameters. The reliability function and the mean-time-to-failure (MTTF) are estimated through the calculation of the posterior samples. Finally, a simulation example is presented to illustrate the proposed bivariate constant-stress accelerated degradation model.
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    Reliability Modeling and Maintenance Policy Optimization for Deteriorating System Under Random Shock
    Lü Yi (吕燚), ZHANG Yun (章云)
    2018, 23 (6):  791-797.  doi: 10.1007/s12204-018-1985-y
    Abstract ( 319 )  
    Performance degradation and random shock are commonly regarded as two dependent competing risks for system failures. One method based on effective service age is proposed to jointly model the cumulative effect of random shock and system degradation, and the reliability model of degradation system under Nonhomogeneous Poisson processes (NHPP) shocks is derived. Under the assumption that preventive maintenance (PM) is imperfective and the corrective maintenance (CM) is minimal repair, one maintenance policy which combines PM and CM is presented. Moreover, the two decision variables, PM interval and the number of PMs before replacement, are determined by a multi-objective maintenance optimization method which simultaneously maximizes the system availability and minimizes the system long-run expect cost rate. Finally, the performance of the proposed maintenance optimization policy is demonstrated via a numerical example.
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    Simulation Study on Multi-Rate Time-Frequency Analysis of Non-Stationary Signals
    LIN Haibo (林海波), GAO Zhibin (高志彬), YI Chuijie (仪垂杰), LIN Tianran (林天然)
    2018, 23 (6):  798-802.  doi: 10.1007/s12204-018-1967-0
    Abstract ( 302 )  
    A new time-frequency analysis method is proposed in this study using a multi-rate signal decomposition technique for the analysis of non-stationary signals. The method uses a multi-rate filter bank for an improved non-stationary signal decomposition treatment, and uses the Wigner-Ville distribution (WVD) analysis for signal reconstruction. The method presented in this study can effectively resolves the time and frequency resolution issue for non-stationary signal analysis and the cross-term issue typically encountered in time-frequency analysis. The feasibility and accuracy of the proposed method are evaluated and verified in a numerical simulation.
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    Comparison of Biomechanical Properties and Hemodynamics of Three Different Vena Cava Filters
    HAN Qingsong (韩青松), CAI Xiangwen (蔡相文), FENG Xiaojuan (冯小娟), ZHANG Qingxiang (张庆祥), FENG Haiquan (冯海全)
    2018, 23 (6):  803-810.  doi: 10.1007/s12204-018-2001-2
    Abstract ( 273 )  
    The interaction mechanism of three types of vena cava filters (VCFs) with blood vessels and their influence on the bloodstream during the process of implantation are investigated by finite element method and computational fluid dynamics. The VCF models are set up with Solidworks software. Using ABAQUS software, we simulate the working conditions of the VCFs in the vessel to analyze the stress distribution and radial support stiffness of the vessel wall and the filter surface. Using FLUENT software, we simulate and analyze the velocity, pressure and shear stress distributions of blood flow when the VCFs are at their working conditions. For the retrievable VCF (R-VCF), the peak stress at the working conditions of the VCF is the highest, the peak stress toward the vessel wall is the lowest, and the support stiffness is the lowest. For the permanent VCF (P-VCF), the peak stress at the working conditions of the VCF is the highest, the peak stress toward the vessel wall is the lowest, and the support stiffness is the highest. Because of the structure of scaffolding support units and the tendency to form intimal hyperplasia on their support units, both the convertible VCF (C-VCF) and the P-VCF can embed their support units in the hyperplasia skin. This effectively prevents them from harming blood veins through filter damage at the pulse load conditions. As the biomechanical property of the C-VCF is between those of the R-VCF and the P-VCF, it has smaller obstacle to blood flow after conversion and has some fragmentation effects on the thrombus. The results show that different types of VCFs differ in their biomechanical and hemodynamic properties after implantation. Therefore, the simulative analysis can provide a reference basis for filter design and clinical decision making.
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    Guaranteed Cost Iterative Learning Control for Multi-Phase Batch Processes
    WANG Limin (王立敏), WANG Runze (王润泽), XIONG Yuting (熊玉婷), WANG Haosen (王浩森), ZHU Lin (朱琳), ZHANG Ke (张可), GAO Furong (高福荣)
    2018, 23 (6):  811-819.  doi: 10.1007/s12204-018-2002-1
    Abstract ( 342 )  
    Batch process is a typical multi-phase process. Due to the interaction between the phases of the batch process, high precision control in a single phase cannot guarantee high precision control of the whole batch process. In order to solve this problem, the guaranteed cost iterative learning control (ILC) of multi-phase batch processes is studied in this paper. Firstly, through introducing the output error, the state error and the extended information, the multi-phase batch process is transformed into an equivalent 2D switched system which has different dimensions. In addition, under the measurable condition, the guaranteed cost iterative learning control law with extended information is designed. The proposed control law ensures not only the stability of the system but also the optimal control performance. Next, in order to study the stability of the system and the minimum running time under the condition of stable running, the multi-Lyapunov function method is used. By means of the average dwell time method, the sufficient conditions ensuring system to be exponentially stable are given in the form of linear matrix inequality (LMI). Finally, the injection molding process is taken as an example to make simulation, which shows the feasibility and effectiveness of the proposed method.
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    Design of Wind Turbine Blade for Solar Chimney Power Plant
    LIU Jia (刘佳), TIAN Rui (田瑞), NIE Jing (聂晶)
    2018, 23 (6):  820-826.  doi: 10.1007/s12204-018-2003-0
    Abstract ( 332 )  
    Aiming at the global efficiency of solar chimney power plant (SCPP), we design a wind turbine generation device to elevate its electricity generating efficiency. Based on wind power utilization theory, a new method is proposed to design a type of wind turbine blade for SCPP. The lift and resistance coefficients on different Reynolds numbers of NACA4418 airfoil, which is suitable for experimental solar electricity generation system, are determined by Profili-V2.0 airfoil design software, a program written in Matlab to calculate chord length of the airfoil. The optimization is conducted by class-shape-transformation (CST) parameterization method and Xfoil software. An airfoil design program is designed on the basis of blade element theory and attack angle with the highest lift coefficient to iteratively determine the inflow angle and setting angle. Prandtl’s tip-loss factor is applied to correct the setting angle, after the airfoil data are input into AutoCAD to build an airfoil model which is then imported into Solidworks to draw blades. A new way is put forward to design wind turbine blades in SCPP.
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    Rigorous Running Time Analysis of a Simple Immune-Based Multi-Objective Optimizer for Bi-Objective Pseudo-Boolean Functions
    ZHOU Shiyuan (周诗源), PENG Xue (彭雪), WANG Yinglin (王英林), XIA Xiaoyun (夏小云)
    2018, 23 (6):  827-833.  doi: 10.1007/s12204-018-2004-z
    Abstract ( 269 )  
    A simple immune-based multi-objective optimizer (IBMO) is proposed, and a rigorous running time analysis of IBMO on three proposed bi-objective pseudo-Boolean functions (Bi-Trap, Bi-Plateau and Bi-Jump) is presented. The running time of a global simple evolutionary multi-objective optimizer (GSEMO) using standard bit mutation operator with IBMO using somatic contiguous hypermutation (CHM) operator is compared with these three functions. The results show that the immune-based hypermutation can significantly beat standard bit mutation on some well-known multi-objective pseudo-Boolean functions. The proofs allow us to understand the relationship between the characteristics of the problems and the features of the algorithms more deeply. These analysis results also give us a good inspiration to analyze and design a bio-inspired search heuristics.
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    Design of Cross-Shaped CPW-Fed Ultrawideband Slot Antenna
    XIANG Niexin (向镍锌), DONG Jiaqiang (董加强), YAN Dong (严冬), WANG Ping (王平)
    2018, 23 (6):  834-837.  doi: 10.1007/s12204-018-2005-y
    Abstract ( 388 )  
    A new design of ultrawideband (UWB) antenna of coplanar waveguide (CPW)-fed is proposed. The antenna is composed of a cross-shaped patch and house-shaped slot with the minimum dimension of 21mm × 20mm × 1.6mm. The analysis of S11, VSWR, radiation pattern and surface current is discussed with HFSS simulation software, and also the effect of parameters is presented. Experimental results show that the bandwidth of the antenna covers 110.67% (3.3—11.6GHz) of UWB range with return loss better than 10 dB. And the good impedance matching in frequency band confirms the antenna is a good candidate for the application of wireless system.
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    Multi-Band Hybrid Mobile Phone Antenna Based on Electromagnetic Coupling
    YAN Dong (严冬), HU Ansha (胡安沙), CHENG Yajun (程亚军), WANG Ping (王平), LI Siwei (李思伟)
    2018, 23 (6):  838-842.  doi: 10.1007/s12204-018-2006-x
    Abstract ( 321 )  
    This research presents a multi-band hybrid mobile phone antenna based on electromagnetic coupling, which can be applied to mobile handheld devices, occupying a small board space of 39.7mm×15.6mm on the system circuit board. By adding resonant and coupled branch instead of multi-feed on the traditional bent antenna, this design provides four wide operating bands of 0.772—0.998 GHz, 1.540—1.600 GHz, 1.680—2.270 GHz and 2.300—2.690 GHz with the hybrid feature of planar inverted-F antenna (PIFA), L-shape, U-shape and S-shape structures, which cover nine-band, i.e., GSM850, GSM900, GPS1575, DCS1800, PCS1900, IMT200, LTE2300, LTE2600 and Blue Tooth/Wi-Fi. Ansoft software HFSS is used in this research to make the antenna performance better and the operating principle of the proposed antenna is described in detail. Result of simulation reveals that the maximum gains of these four wide bands are 2.20, ?0.99, 4.01 and 4.05 dBi, respectively. Moreover, this research also tests the return loss (S11) of the fabricated antenna with the vector network analyzer and the result is in accordance with the simulation result on the whole. There are four wide resonant frequencies which cover nine-band of wireless wide area network (WWAN), wireless local area network (WLAN) and long term evolution (LTE), when the available bandwidth is better than 6 dBi return loss.
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