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Table of Content

      
    20 December 2015
    Volume 45 Issue 6
    An image saliency object detection algorithm based on information diffusion
    REN Yongfeng, ZHOU Jingbo
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  1-6.  doi:10.6040/j.issn.1672-3961.0.2015.176
    Abstract ( 758 )   PDF (2152KB) ( 626 )   Save
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    In order to better extract salient regions in images, we proposed an image salient region detection algorithm based on information diffusion mechanism. The proposed algorithm was divided into three steps. First, we segmented an input image into superpixels which were represented as the nodes in a graph. The node with high frequency was generated by the characteristics of the salient regions. Then, according to high-frequency nodes, convex hull computation was used to generate the saliency seeds of the salient object area. Finally, based on the seeds obtained by convex hull computation, the second-order Gaussian-Markov random fields were used to diffuse the information from saliency seeds to others, thereby forming the saliency region for a given image. The experimental results showed that the quadratic programming solution exploited to compute the weights between the nodes can effectively avoid threshold selection and enhance robustness accordingly. In addition, the proposed method performed better than the other state-of-the-art methods.
    Chinese entity relation extraction based on entity semantic similarity
    XU Qing, DUAN Liguo, LI Aiping, YIN Guimei
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  7-15.  doi:10.6040/j.issn.1672-3961.2.2015.085
    Abstract ( 1020 )   PDF (1723KB) ( 680 )   Save
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    In order to explore the impact of the semantic similarity on the Chinese entity relation extraction, two new features were proposed, which were the "TongYiCi Cilin" code tree constructed with the entities'5 layer code in "TongYiCi Cilin" and the entity semantic similarity tree constructed with the average of the semantic similarity between the entity word in relation instance and all entity words in each category of relation. The impact on the relation extraction performance of these two new features together with the existing "TongYiCi Cilin" code feature and the entity type information feature was explored. In the cases with single features, the entity type feature got the best performance, and the F values of subtype and type were 84.9 and 83.2; In the cases with combination features, the combination of the entity type feature and the "TongYiCi Cilin" code tree feature got the best performance, the F values of both subtype and type were 2.5 higher than the entity type feature. But the performance of three combinations features became poorer instead of better. The results showed that the "TongYiCi Cilin" code tree was an effective supplement of the entity type information, but excessive features may result in information redundancy and poor performance.
    Decentralized finite-time robust connective stabilization for large-scale descriptor systems with expanding construction
    LI Xiaohua, YAN Wei, LIU Yang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  16-28.  doi:10.6040/j.issn.1672-3961.0.2015.148
    Abstract ( 743 )   PDF (1803KB) ( 352 )   Save
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    Robust decentralized finite-time connective stabilization for a class of large-scale descriptor systems with expanding construction was studied. The mathematic model of the expanding large-scale descriptor system was established. The sufficient conditions of decentralized finite-time connective stabilization for this kind of systems were deduced based on state feedback and dynamic output feedback by using stability theory and LMI(linear matrix inequality) method. And the design method of the robust decentralized connective stabilization controller meeting the conditions for the newly added subsystem was given without any change on the decentralized control laws of the original large-scale descriptor system. Simulation on a numerical example for interconnected descriptor systems showed that the expanding system could be finite-time connective stabilized, and the feasibility and effectiveness of the proposed method were verified.
    State feedback controller design for fractional order system in the triangular form
    ZHAO Yige, WANG Yuzhen
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  29-35.  doi:10.6040/j.issn.1672-3961.0.2015.201
    Abstract ( 661 )   PDF (1028KB) ( 438 )   Save
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    Some new properties for Caputo fractional derivative were presented, and a sufficient condition of asymptotical stability for fractional order nonlinear systems was obtained based on the new properties. By using the Backstepping technique, the state feedback control design problem for fractional order nonlinear systems in the triangular form was investigated. Two illustrative examples were provided to illustrate the effectiveness of the main results.
    Item assignment optimization of automatic picking system based on hybrid picking strategy
    LIU Debao, WU Yaohua, GUO Yaoyang, WANG Yanyan
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  36-44.  doi:10.6040/j.issn.1672-3961.0.2015.061
    Abstract ( 881 )   PDF (2936KB) ( 527 )   Save
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    To improve the efficiency of the automatic picking system, a novel hybrid picking strategy combining the advantages of serial and parallel picking strategies was proposed. The noninterference items were sorted in parallel first. Then the appropriate item were sorted to fill in the gaps between the items after parallel picking. Finally, the remaining items were sorted in serial. Since item assignment affects the performance of the hybrid picking strategy, it was optimized by a modified niched genetic algorithm. Experimental results illustrated the feasibility and effectiveness of the hybrid picking strategy and item assignment optimization for improving the efficiency of the automatic picking system.
    Synchronization of multiwing hyperchaotic systems via adaptive sliding mode control
    SUN Meimei, HU Yun'an, WEI Jianming
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  45-51.  doi:10.6040/j.issn.1672-3961.0.2014.155
    Abstract ( 665 )   PDF (3105KB) ( 365 )   Save
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    An adaptive sliding mode control scheme was presented for the synchronization of a class of multiwing hyperchaotic system with uncertainties and unknown external disturbances. The sliding mode control and parameter adaptive principle were designed to realize the synchronization between the master system and slave system. Adaptive control technique and the sliding mode technique were both used to introduce robustness and eliminate systematic uncertainties and affections from external disturbances. It is proved that synchronization errors converge to a small neighbourhood of the origin by using Lyapunov stability theory. Finally, simulation results verified the effectiveness of the proposed control scheme.
    Topology optimization of new flexible structure guardrail ends
    LEI Zhengbao, NING Han
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  52-56.  doi:10.6040/j.issn.1672-3961.0.2015.090
    Abstract ( 820 )   PDF (2571KB) ( 597 )   Save
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    According to develop a new flexible guardrail terminal which can meet the new regulations in our country, topology optimization of the end head of a novel flexible guard rail under the condition of bus collision was analyzed by adopting the method that combines the analysis of model simulation of the finite element of the car-barrier,full scale crash test of real vehicle with topology optimization of cellular automaton, which was based on the new evaluation criteria both at home and abroad. Under five different condition,topology optimization of flexible guard rail end head design area was analyzed. Moreover, a new topological configuration of flexible guard rail was obtained. Finally, the simulation software was used to simulate and verify the topology of the end head of the four corner arc. The analysis results indicated that:the end head topology of 0.3 mass fraction was able to avoid the occurrence the trip of car body, too high acceleration and rollover accident which was caused by the too high strength of the end head of the flexible guard rail. The maximum acceleration of the car body X, Y, Z axis were respectively 11.0, 0.38, 4.0g, which were all less than evaluation standard acceleration-20g. It meets the safety requirements of the collision. Therefore, it can ensure the normal protection ability of highway guard rails because it can provide enough binding force for highway fences.
    Constructing the model of closed-loop control system based on function packet sets
    DU Yingling, WANG Jimei, SU Yan, LI Jinxia, SHAO Changbo
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  57-64.  doi:10.6040/j.issn.1672-3961.0.2014.088
    Abstract ( 549 )   PDF (1056KB) ( 316 )   Save
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    To recognize the disturbance source existing in the closed-loop control system, and to eliminate the disturbance law hidden in the system, Inferring and minding further about the dynamic characteristic and law characteristic of function P-sets(function packet sets), the concepts of F-shrinking law, F-extending law,(F,F)-two directions law pair, F-shrinking law clusters, F-extending law clusters, and(F,F)-two directions law clusters were proposed, and definitions of shrinking degree, extending degree, shrinking degree set and extending degree set were given, which were used to identify the disturbance law existing in closed-loop control system. The disturbance recognition rule of(F,F)-two directions law was presented, and the model of closed-loop control system basing on function P-sets was constructed. After experimental verification, it could be found that the given method was effective, while it provided a new theoretical tool for the recognition and cancellation of disturbance law in the actual production and living.
    Dynamic modeling of tail rope and swing parameters analysis
    LI Chao, WANG Zengcai, ZHANG Wanzhi, HUANG Xianhua, ZHU Shuchuan, MENG Huai
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  65-70.  doi:10.6040/j.issn.1672-3961.0.2015.107
    Abstract ( 765 )   PDF (1727KB) ( 494 )   Save
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    To solve the short-life problem of hoist tail rope caused by the swing of tail rope during the lifting movement, the visco-elastic vibration model was built based on the discretization modeling method and the ADAMS(automatic dynamic analysis of mechanical systems) software. The characteristic of the tail rope was studied by implementing the motion simulation. The test was designed to record swing amplitude of the tail rope at the shaft bottom. Test results were compared with simulation results to verify the rationality of the model. The influence of different parameters on the swing amplitude of the tail rope was analyzed. The results showed that the maximum swing amplitude of the micro segments of tail rope was generated at the shaft bottom, which was closely related to the vertical rotational stiffness coefficient KTZ and the vertical rotation damping coefficient CTZ as well as the mass. The left swing amplitude was most greatly influenced by the rotational stiffness coefficient while the right swing amplitude was most affected by the mass. When 50% improvement of the parameters of the model is achieved, the left and right swing amplitude were increased by 26.41% and 21.75%, respectively. Test results were basically in line with the simulation results, which could provide a reference for the selection of tail rope and construction of the isolation device.
    Mathematical model and simulation of pipe-annulus welding assemble surface and opening
    WANG Qiang, XU Lei, PENG Shaofeng
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  71-75.  doi:10.6040/j.issn.1672-3961.0.2015.111
    Abstract ( 638 )   PDF (1221KB) ( 436 )   Save
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    Since the parametric equation of complex pipe-annulus truss could not be solved easily, a solution based on Newton iteration was presented. Newton iterative function was established based on the parametric equations of pipe and annulus, by utilizing the geometric constraints between intersecting bodies and successive approximation with an appropriate initial iteration value, the parametric equation was solved. The actual cutting angle of pipe-annulus intersecting on its mating surface was deduced; two types of pipe-annulus intersecting mating surface with a blunt edge, the riding type and the inserting type, were extended. Newton iteration is suitable for solving parametric equation of complex intersecting bodies' intersecting line for its advantage of simple programming and fast convergence. Contrasted the intersecting line between iterative algorithm and entity Boolean operations, the results demonstrated that the deviation of Newton iterative is small, and its accuracy and reliability was considerable.
    Prediction models of PM2.5 mass concentration based on meteorological factors
    LIU Jie, YANG Peng, LYU Wensheng, LIU Agudamu, LIU Junxiu
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  76-83.  doi:10.6040/j.issn.1672-3961.0.2014.214
    Abstract ( 861 )   PDF (2210KB) ( 1369 )   Save
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    In order to get the optimal prediction model, the prediction models of PM2.5 mass concentration based on multiple linear regression and machine learning were developed. Basic values of pollutants mass concentrations and periodical factors were introduced as predictive inputs based on meteorological factors. Then four prediction models were developed for comparison. Results showed that goodness of fit of multiple linear regression model based on improved predictive inputs was increased from 0.52 to 0.64. The selected meteorological factors, basic values of pollutants mass concentrations and periodical factors could accurately describe daily variation of PM2.5. BP neural network and support vector machine models could be trained to model the highly non-linear relationships between PM2.5 mass concentration and predictive inputs. They provided satisfactory results with goodness of fit of 0.69 and 0.74, respectively. Support vector machine model was proved to be optimal prediction model of PM2.5 mass concentration.
    Field test and research on vehicle load induced dynamic pore pressure in asphalt pavement
    TANG Weize, OU Jinqiu, CUI Xinzhuang, LOU Junjie, XIAO Ming, ZHANG Jiong, HUANG Dan, HOU Fei
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  84-90.  doi:10.6040/j.issn.1672-3961.0.2015.098
    Abstract ( 866 )   PDF (3648KB) ( 710 )   Save
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    In order to study the influence on moisture damage of asphalt pavement caused by dynamic pore pressure due to moving vehicle loads, and explore the time histories of dynamic stress and dynamic pore pressure in the pavement surface layers, the heat-resistant dynamic stress and pore pressure sensors were developed and used to measure the dynamic stresses and pore pressures in the field, and the field measured data of dynamic pore pressure was acquired. Based on the Biot's consolidation theory, a numerical fluid-solid coupling simulation method reflecting mobile effect of wheel load was used to analyze the response of pavement under the actual condition. The time history of dynamic pore pressure in pavement was quantitatively analyzed. Numerical simulation results matched well with in situ test data. The pump-suction effect of dynamic pore pressure that continuously generated in pavement void under cyclical vehicle loads led to the reduce of the asphalt-aggregate bond strength and further triggered the moisture damage. This study verified the hydraulic drive mechanism of moisture damage, and provided a theoretical guild for the moisture damage research and pavement design.
    Power demand forecasting in Shandong province with system dynamics
    YU Songqing, HOU Chenghao, SUN Yingtao
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  91-98.  doi:10.6040/j.issn.1672-3961.0.2015.084
    Abstract ( 723 )   PDF (2765KB) ( 507 )   Save
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    To enhance the depth and breadth of choice about the influence factors of power demand, a systematic analysis was made to the society power demand based on system dynamics, and the system dynamics model of power demand forecast were established, which reflects the multiple factors. The accuracy of system dynamics model was verified by historical data, and then was used to simulate and predict the power consumption in Shandong Province. Final, the relevant policy was analyzed for saving technology and urbanization process variable, and some policy suggestion was put forward.
    Research on the electromagnetic responses of azimuthal resistivity logging in formation boundaries
    GAO Yang, KONG Fanmin, LI Kang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2015, 45(6):  99-106.  doi:10.6040/j.issn.1672-3961.0.2014.259
    Abstract ( 817 )   PDF (3824KB) ( 533 )   Save
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    The electromagnetic field of different azimuth was calculated by analytical method, and then its application for forecasting formation boundaries was researched. By studying the reflection and transmission of electromagnetic wave on each layer, an analytic expression for electromagnetic wave was obtained, which satisfied boundary condition of each layer, and then the amplitude-attenuation and phase-shift of electromagnetic wave resistivity logging were computed. The sensitivity to formation boundaries of directional electromagnetic measurements was analyzed, and the influence of formation relative dip angle and receiver antenna dip angle on directional measurements was also studied. The results showed that the directional detection range increased with the coil spacing and the thickness of target bed increasing. The change of directional amplitude-attenuation became more obvious with the formation relative dip angle and receiver antenna dip angle increasing when the tool was approaching formation boundary, and thus the sensitivity to formation boundaries increased. By combining azimuthal resistivity image with directional electromagnetic response, the results showed that adding tilt antenna to conventional logging while drilling resistivity tools, the formation boundaries could be accurately forecasted.