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Table of Content

      
    20 August 2017
    Volume 47 Issue 4
    Optimization algorithm for big data mining based on parameter server framework
    LIU Yang, LIU Bo, WANG Feng
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  1-6.  doi:10.6040/j.issn.1672-3961.0.2016.339
    Abstract ( 740 )   PDF (1295KB) ( 332 )   Save
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    Traditional machine learning algorithms for small data were not applicable for mining of big data. An optimization algorithm for machine learning and big data mining was proposed. The iterative computation of machine learning algorithms was divided into two phases according to the change of model vector. According to the observation that most samples contributed little to the model update during the iteration, the computation load of machine learning algorithms could be reduced by reusing the iterative computing results of this kind of samples. The experimental results showed that the proposed method could reduce the computation load by 35%, with little effect on prediction accuracy of the training model.
    3D facial expression tracking using a monocular RGB camera
    HUANG Yanhui, FAN Yangyu, SU Xuhui
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  7-13.  doi:10.6040/j.issn.1672-3961.0.2016.466
    Abstract ( 766 )   PDF (4069KB) ( 472 )   Save
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    There were two key problems in tracking 3D facial expression using a monocular RGB camera. One was how to reconstruct 3D facial model from a single image, and the other was how to establish the dense correspondences between the different 3D models. To solve the above problems, an effective 3D facial expression tracking algorithm was proposed. The feature points were automatically detected on each input facial image frame, and the 3D models of different expressions were reconstructed by Multilinear Model according to 2D feature points. By re-projecting the 3D models into the image space, the Optic Flow and Sift Flow correspondences between images were calculated. According to the correspondences of the images, the 3D models were rectified by Laplacian mesh deformation, and the dense 3D correspondences between different expressions were established. The experimental results showed that the proposed method could create more realistic 3D expression models, and could accurately track the continuous change of the 3D expression sequence.
    Blind image restoration using alternating direction method of multipliers
    LI Zhenwei, CUI Guozhong, GUO Congzhou, YU Changhao
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  14-18.  doi:10.6040/j.issn.1672-3961.0.2017.008
    Abstract ( 809 )   PDF (1528KB) ( 367 )   Save
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    In order to overcome the low operating efficiency and poor reconstruction quality in the total variation blind image restoration model of the regularization theory, an iterative algorithm of blind restoration based on alternating direction method of multipliers algorithm was proposed. The restored image and the point spread function were estimated alternatively by alternating iteration to improve the running speed and reconstruction quality through a way without updating the penalty term. The normalization and threshold constraint condition of the point spread function, and the positive definite condition of the image were added while calculating. In the numerical experimentation, the blind restoration of the images with different fuzzy types were carried out, and it was compared with other existing blind image restoration methods. The proposed algorithm could improve the quality and the resolution ratio of the image. Through objective comparison, the peak signal to noise ratio of the proposed algorithm could be increased by 1.2 dB at most,the average structural similarity was increased maximumly by 1% and the computation time was saved maximumly by about half.
    A new 3D model retrieval method based on manifold ranking
    MOU Chunqian, TANG Yan, HU Jinge
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  19-24.  doi:10.6040/j.issn.1672-3961.0.2016.382
    Abstract ( 750 )   PDF (1668KB) ( 370 )   Save
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    Most existing view-based 3D model retrieval methods used features of 2D projection views to represent a 3D model directly, ignored their contributions to a 3D model. Therefore, a new 3D model retrieval method based on manifold ranking was proposed, which focused on the contributions of 2D projected views features. 2D projected views from 34 different viewpoints obtained through rotation, word frequency vector featuresextracted by bag-of-feature based on scaleinvariant feature transform(SIFT)features, then aggregated 34 word frequency vector features of a 3D model into a 3D model feature. The experimental results showed that our method improved the retrieval accuracy well.
    Improved bi-variables estimation of distribution algorithms for multi-objective permutation flow shop scheduling problem
    PEI Xiaobing, CHEN Huifen, ZHANG Baizhan, CHEN Menghui
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  25-30.  doi:10.6040/j.issn.1672-3961.0.2016.256
    Abstract ( 757 )   PDF (2086KB) ( 269 )   Save
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    Aiming at permutation flow shop scheduling problem(PFSP)with the minimum maximum makespan, the minimum maximum tardiness and the minimum total flow time as objectives, improved bi-variable estimation of distribution algorithm(IBVEDA)based on bi-variables estimation of distribution algorithm(BVEDA)was proposed. Building blocks was designed using bi-variable probability model of IBVEDA, according to combination probability formula for block competition and block mining, then artificial chromosomes were generated using high quality blocks to improve the quality of solution in the evolution process. To enhance the diversity of algorithm, dispatching rules, the shortest processing time, longest processing time,earliest due date were added in parallel evolution while injecting artificial chromosomes, the number of individual for next iteration processed by the methods above depended on the above methods top 10 total weighted fitness of last iteration to do dynamic adjustment, finally Pareto dominance was used to select and save non-dominated solutions. The experiment used C++ code tested on Taillards standard instances, IBVEDA was compared with SPGAⅡand BVEDA and solution distribution of the three algorithms were plot which the effectiveness of IBVEDA was validated.
    Self-adaptive sliding mode control of fractional-order Victor-Carmen chaotic systems
    MAO Beixing, CHENG Chunrui
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  31-36.  doi:10.6040/j.issn.1672-3961.0.2016.327
    Abstract ( 613 )   PDF (1608KB) ( 248 )   Save
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    The problem of sliding mode synchronization of fractional-order Victor-Carmen systems was studied using self-adaptive sliding mode control approach based on fractional-order calculus theory. The fractional-order slding mode function was designed, the controllers and the strict proof in mathematics using Lyapunov stability theory were given. Two sufficient conditions were arrived for the fractional order systems getting sliding model synchronization. The research conclusion illustrated that fractional-order multi-scroll systems was sliding mode chaos synchronization under proper controllers and sliding mode surface.The numerical simulations demonsrrated the effectiveness of the proposed method.
    A soft starting method for the isolated DC/DC converter in DC distribution systems
    PAN Yiwei, YUAN Shuai, CHEN Alian, ZHANG Chenghui
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  37-42.  doi:10.6040/j.issn.1672-3961.0.2017.101
    Abstract ( 709 )   PDF (3130KB) ( 230 )   Save
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    To solve over current problem of the isolated DC/DC converter that commonly applied in DC distribution systems, a novel simple soft starting method was proposed. During the starting time, the dutycycle of the input side square wave voltage gradually changed from 0 to 0.5, while the DC voltage ramped from 0 to the final set value at the same time by phase shift control. By applying these two methods, current overshooting and capacitor voltage oscillation could be effectively suppressed. The system had a strong anti-disturbance capacity and do not require complex mode switching procedure as conventional soft starting method. Simulation results were provided to validate the effectiveness of the proposed soft starting method.
    Synchronization of time-delayed complex dynamical networks with discontinuous coupling
    ZHANG Yuting, LI Wang, WANG Chenguang, LIU Youquan, SHI Hongjun
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  43-49.  doi:10.6040/j.issn.1672-3961.0.2016.122
    Abstract ( 894 )   PDF (1988KB) ( 351 )   Save
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    The synchronization problem of complex dynamical networks with time delay and discontinuous coupling was investigated based on Lyapunov stability theory. The sufficient conditions for the networks synchronization was established and the upper bound estimation of the time delay was obtained. The acquired analytical results showed that network with discontinuous coupling could achieve synchronization if time delay met some conditions. The upper bound of the delay for synchronization depended on the coupling strength, the algebraic connectivity of network and on-off rate. The application of numerical simulation results proved that evolution trajectory of network synchronization error and different conditions, in which Ikeda system was used as node dynamics and error function as the network synchronization index. Furthermore, the effect of control parameters on the synchronization speed was analyzed. Numerical examples were provided to verify the effectiveness of the theoretical results.
    Design of LQG controller for vehicle active suspension system based on alternate iteration
    YU Yuewei, ZHOU Changcheng, ZHAO Leilei, XING Yuqing, SHI Peilin
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  50-58.  doi:10.6040/j.issn.1672-3961.0.2016.462
    Abstract ( 672 )   PDF (3667KB) ( 375 )   Save
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    For the active suspension LQG(linear-quadratic-Gaussian control)controller, an objective and fast method to determine the optimal control weighting coefficient and control force was established. Through analysis of riding comfort evaluation index of vehicle, using dimensionless normalized thoughts, the optimal control objective function of active suspension was established, and the relationship between ride comfort weighted coefficient and control weight coefficient was obtained. According to 1/4 vehicle active suspension mechanical model, using Newmark-β integration method, a simulation analysis model for the weighted coefficient of ride comfort was established. Using the road roughness as input, the tire dynamic displacement and suspension dynamic deflection as constraint conditions, by referring to alternative iterative thoughts, the alternating iterative optimization algorithm was established, an optimization design method of LQG control weighted coefficient and control force was presented. By comparing with the existing LQG controller design method, the optimal control weighting coefficient and control force design method were verified. The results showed that the LQG controller could significantly improve the ride comfort of vehicle.
    Influence of ozone addition on laminar flame speed in methane-air lean mixtures
    XIAO Di, LIAN Jing, JI Shaobo, ZHAO Shengjin, XU Huaimin
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  59-63.  doi:10.6040/j.issn.1672-3961.0.2016.352
    Abstract ( 822 )   PDF (1839KB) ( 356 )   Save
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    A new method was proposed to improve lean burn combustion performance of natural gas engine and to solve the problems of high ignition energy and slow flame speed of combustion of natural gas in lean burn condition by using the ozone with strong oxidation. The influence of ozone addition on laminar flame speed was studied and numerical analysis of chemical mechanism was carried out using Chemkin software. Results showed that laminar flame speed increased with ozone addition and improvement was more obvious with lean mixture. Moreover, laminar flame speed could be increased in different temperature and pressure situation with ozone addition and the maximum increment of laminar flame speed could reach 36%.The concentration of free radicals and intermediate products increased obviously with ozone addition and then improved the combustion characteristics of methane.
    16Mn pipe strain aging after service by automatic ball indentation test
    YANG Yan, WANG Weiqiang, PAN Lu, SONG Mingda
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  64-69.  doi:10.6040/j.issn.1672-3961.0.2016.467
    Abstract ( 670 )   PDF (1581KB) ( 543 )   Save
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    The evaluation of strain aging was a difficult problem for in-service and un-sampling equipment. The 16Mn pipe was used as research material. The values of yield strength, tensile strength, impact absorbing energy and fracture toughness of the material which before and after the strain aging were compared by the automatic ball indentation tests and conventional mechanical experiments. And the application of the automated ball indentation tests in the strain aged steel was further discussed. The results showed that the automatic ball indentation tests could be used to accurately measure the mechanical properties of the material after the strain aging. So the mechanical performance of the in-service equipment could be acquired regularly by the automatic ball indentation technology, and according to the actual test mechanical properties to adjust operating pressure or replacement equipment, it could facilitate the safe operation of equipment, moreover it could extend the service life of equipment.
    Analysis and optimization of urea deposits formation in urea-SCR systems
    BAI Fengyue, WEN Bangyao, BAI Shuzhan
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  70-76.  doi:10.6040/j.issn.1672-3961.0.2017.047
    Abstract ( 1208 )   PDF (2743KB) ( 492 )   Save
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    Urea crystallization in the urea selective catalytic reduction(urea-SCR)system was analyzed by detecting the components of the deposits with thermo-gravimeter-fourier transform infrared spectroscopy(TG-FTIR)technology and simulating the air motion in the exhaust system with computational fluid dynamics(CFD)technology. To solve the problem of urea solution hitting the wall and poor atomization, the integral nozzle mountings structure and integrated nozzle seat package structure were put forward based on the CFD results, and the exhaust temperature when it started to spray and the injection rate of urea solution were optimized with engine bench tests. The results indicated that there were no urea deposits in the optimized structures when the exhaust temperature reached 272 ℃ or the injection rate of urea solution reached 5 g/min, thus solved the urea crystallization problem, which could provide effective methods for design and optimization of SCR systems for diesel engines.
    Algorithm and error analysis of tool geometric parameters detection based on machine vision
    HOU Qiulin, SUN Jie, HUANG Panling, SUN Chao, MOU Wenping
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  77-82.  doi:10.6040/j.issn.1672-3961.0.2017.064
    Abstract ( 772 )   PDF (1926KB) ( 448 )   Save
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    A bounding rectangle algorithm of connected component was investigated for measuring tool geometrical parameters. An in-position detection system for measuring tool geometrical parameters was developed based on machine vision, which were to solve the problem of wrong tool because of tools’ change frequently in NC machining process of aeronautical monolithic components. The system was carried out by means of using industrial cameras, dual-telephoto lens and others to collect tool image, and using image processing software MATLAB to have image pretreatment including grayscale transformation and binarization. The processes of connected component labeling algorithm and bounding rectangle algorithm were analyzed. The results showed that diameter error was less than 0.01 mm and hanging length error was less than 0.08 mm in the in-position detection system for measuring tool geometrical parameters based on machine vision. The system had a high response speed, high measuring accuracy and anti-noise performance.
    High precision algorithm of metal detector based on balance coil
    BAI Shuzhong, DONG Chunyang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  83-88.  doi:10.6040/j.issn.1672-3961.0.2016.112
    Abstract ( 999 )   PDF (1807KB) ( 664 )   Save
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    Metal detector is widely used in food security and industrial manufacture. In order to solve the product effect problem which used only amplitude feature, the dual channel digital detecting algorithm was put forward based on amplitude and phase information, also the balance coil mathematical model was built, and the metal signal feature was deeply analyzed. Through the coordinate orientating,the amplitude and phase information of metal could be exactly extracted, product learning and clustering algorithm could efficiently separate the metal signal and product effect signal. The experiment results showed that the phase information could separate different material metal effectively, cooperated with the amplitude information, the dual channel digital detecting algorithm could extract the metal information accurately and detect the metal with strong product effect.
    Correlation analysis between transmission line parameters and operation modes
    HOU Guangsong, GAO Jun, WU Yanda, ZHANG Xin, DENG Ying, LI Changgang, ZHANG Yaping
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  89-95.  doi:10.6040/j.issn.1672-3961.0.2016.422
    Abstract ( 868 )   PDF (1879KB) ( 713 )   Save
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    To solve the problem that the parameters under actual operation modes may be different from the database, a transmission line parameter identification model based on phasor measurement unit data was presented to identify the line parameters. Based on field measurement data, the correlation between changes in line parameters and current and voltage was analyzed. The high correlation between the reactance parameter of actual transmission lines and current was obtained. The correlation between different transmission lines was different. Study result was helpful to enhance the accuracy of database.
    Online modal parameter identification and fault diagnosis of wind turbines based on order analysis
    LI Jingli, WANG Qian, ZHANG Jun, LI Leilei
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  96-102.  doi:10.6040/j.issn.1672-3961.0.2016.394
    Abstract ( 748 )   PDF (1759KB) ( 594 )   Save
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    According to the health monitoring and early warning evaluation of wind turbines, the modal parameter identification based on the ambient load excitation and the computed order analysis methods were applied in the online modal analysis of wind turbine gearbox system. An online modal parameter identification and fault diagnosis system for wind turbines was designed and developed. Comparison of test results between experimental modal and online modal parameter identification, and online modal identification parameters due to the different ambient load excitation condition, showed that methods for online modal parameter identification were feasible, real-time, stable and reliable. By now, a large amount of data for online modal measurement, dynamic characteristics due to varied ambient load excitation and fault diagnosis of wind turbines has been provided.
    Difference calculation of grounding grid performance under different soil layered structures
    TAO Yaguang, LI Tianjiao, TIAN Ye, WANG Zhaojun, CHENG Famin, LI Qingquan
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  103-109.  doi:10.6040/j.issn.1672-3961.0.2017.100
    Abstract ( 705 )   PDF (4293KB) ( 561 )   Save
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    In order to quantify the difference in safety performance of the substation grounding network under different soil structures as much as possible, based on the measured soil resistivity data, the substation ground network safety indicators, such as step voltage and touch voltage of the mountains, coastal and hilly areas under the vertical layered soil structure and the level layered soil structure were analysed, and the differences between regions in percentage were evaluated. The results showed that the soil vertical layered structure and horizontal layered structure could be accurately calculated by using current distribution, electromagnetic field and soil analysis(CDEGS)software,the necessity of considering vertical layered soil was explained by the contrast of step voltage and touch voltage under two kinds of soil structure in different regions,deviation percentage of touch voltage and step voltage near the soil interface part under vertical stratification structure were higher at the same area, and the calculation results of maximum deviation percentage showed that the difference caused by different soil layers structure was more obvious in the bigger resistivity region
    Remote testing on low voltage ride through of offshore wind turbines
    XIE Caike, JIANG Ziming, LIU Yutian, WANG Chunyi
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  110-116.  doi:10.6040/j.issn.1672-3961.0.2016.218
    Abstract ( 780 )   PDF (3760KB) ( 573 )   Save
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    In order to cope with the long-distance submarine cable effects on low voltage ride through(LVRT)remote testing for offshore wind turbines(WTs), the LVRT testing model was built and the method for remote testing on LVRT of offshore WTs was proposed according to the existing LVRT testing technique and standards based on the outlet of WTs. The difference between near and remote testing in both steady and transient situations was analyzed according to the existing devices and method, which concluded that the mutual influence of current limiting reactance and cable heightened the voltage of the outlet, prolonged the transient process and increased harmonic component. The circuit breaker of original device was replaced with electronic switches in order to control the operation of reactance accurately. The operation sequence of the reactance was improved to make the action intervals of time between the current-limiting reactance and short-circuit reactance trended to 0. By doing this, the mutual influence of current-limiting reactance and cable could be avoided. A simulation was put forth to verify the effectiveness of the improved process and to provide supports for development of remote LVRT testing equipment at the same time.
    Fe3O4 magnetic dispersive solid-phase extraction with graphene for determination of organochlorine pesticides contaminants in water
    WANG Mingyu, SU Liqing, ZHANG Shaojun, WANG Yu
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  117-123.  doi:10.6040/j.issn.1672-3961.0.2017.002
    Abstract ( 586 )   PDF (1772KB) ( 526 )   Save
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    A novel dispersive solid-phase extraction(DSPE)analysis method was established by combining Fe3O4magnetic nanoparticles modified graphene as absorption material for determination of organochlorine pesticides(OCPs)in water. Magnetic nanoparticles modified graphene(MNG)was prepared by graphene oxide and Fe2+ through redox reaction in one step. Cationic surfactant CTAB was added as micelle forming agent, in which MNG was carrier of mixed micelles extraction system. Mixed micelle modified MNG had higher loading capacity than pure Fe3O4magnetic graphene. This method was applied to detect 29 kinds of OCPs in water. The detection limit was in the range of 1.5~5.0 ng/L. The recovery was ranged from 75.22% to 97.15%. The relative standard deviation(RSD)of repeatability was lower than 9.995%. As compared with ordinary solid-phase extraction, the sensitivity of new method increased 50~113 times. The method was suitable for simultneous determination of OCPs pesticide residues in water with high accuracy, sensitivity and less pre-treatment time, which was suitable for batch analysis of samples.
    Performance of mature aerobic granules under the absence of organic carbon source
    YUAN Shasha, YU Haibo, GAO Mingming, WANG Xinhua
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2017, 47(4):  124-130.  doi:10.6040/j.issn.1672-3961.0.2017.050
    Abstract ( 697 )   PDF (2027KB) ( 351 )   Save
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    Physicochemical properties, microbial activities, extracellular polymeric substances(EPS)and structure stability of mature aerobic granules were studied to investigate the effect of organic carbon source absence on the stability and nitrification activity of aerobic granules, the capability of upholding shock of aerobic granules was tested. Results showed that microbial activity of ammonia oxidizing bacteria(AOB)and nitrite oxidizing bacteria(NOB)increased, and high nitrifying activity achieved on 60 d under the absence of organic carbon source. Under the absence of organic carbon source, particle size of aerobic granules decreased. Aerobic granules became compacter with loss of filamentous bacteria and increase of spherical bacteria. EPS mass concentration and the mass ratio of polysaccharide and proteins increased. Under the absence of organic carbon source, mature aerobic granules didnt disintegrate completely and had good capability of upholding shock. This study verified the potential of aerobic granules treating wastewater under the absence of organic carbon source, and provided fundamental basis for the practical application of aerobic granules.