Loading...

Table of Content

      
    20 February 2016
    Volume 46 Issue 1
    An incremental approach for reduction based on knowledge granularity
    JING Yunge, LI Tianrui
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  1-9.  doi:10.6040/j.issn.1672-3961.2.2015.033
    Abstract ( 990 )   HTML   PDF (934KB) ( 607 )   Save
    References | Related Articles | Metrics
    The object set in a decision table varied dynamically nowadays. It cost a lot of time for non-incremental algorithms solving reduction of dynamical data set. Incremental technique supplied an efficient and effective soluation to such dynamic data. An incremental mechanism for updating knowledge granularity was introduced and then an incremental approach for attribute reduction based on knowledge granularity was developed. With the existing knowledge granularity and reduction, the new reduction could be obtained by the proposed method when multiple objects were added to the decision table. Theoretical analysis validated that incremental approach could reduce complexity of time for computing attribute reduction. Experiments conducted on different data sets from UCI showed that the proposed incremental algorithm could achieve better performance than the non-incremental approach.
    Articles
    The mining of hot events based on information flow of short message texts
    LIU Jinling1, WANG Xingong2, ZHOU Hong1
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2013, 43(03):  7-12. 
    Abstract ( 228 )   PDF (1259KB) ( 312 )   Save
    Related Articles | Metrics

    The text information flow of SMS had carried abundant information resources. In order to find out the hot events behind it, an online sorting algorithm was  given for the text information flow of SMS. This method  used the cooccurrence frequency of feature words to define its relevance. And the similarity of message texts was  defined on the basis of preamble information collection and information frequency. Furthermore, after each time period of clustering,  the clustered SMS texts were classified periodically. This algorithm had higher efficiency to find hot events for a large number of short text information retrieval. Moreover, this algorithin  reduced the possibility of false detection and missed detection. Based on the comparison of experiments on algorithms between real data sets and SinglePass, the  results  showed that  each index was improved to some degree.

    A neighborhood preserving embedding algorithm based on global distance and label information
    MEI Qinglin, ZHANG Huaxiang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  10-14.  doi:10.6040/j.issn.1672-3961.0.2015.296
    Abstract ( 877 )   HTML   PDF (1811KB) ( 856 )   Save
    References | Related Articles | Metrics
    An algorithm of neighborhood preserving embedding based on global distance and label information was proposed. A global factor that characterized the global distance and a function term that characterized the label information were added in the traditional Euclidean distance formula of adjacent graph. Global factor could make unevenly dirtibuted samples smooth and uniform, label information could make intra-class compact and inter-class separable, which improved quality of neighborhood and constructed an optimal adjacency graph, and improved classification accuracy. Experimental results showed that the proposed algorithm had higher accuracy and performed more effective than traditional neighborhood preserving embedding algorithm.
    Time series similarity searching algorithm based on Map/Reduce
    WANG Huiqing, SUN Hongwei, ZHANG Jianhui
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  15-21.  doi:10.6040/j.issn.1672-3961.1.2015.172
    Abstract ( 1041 )   HTML   PDF (1909KB) ( 781 )   Save
    References | Related Articles | Metrics
    The strategy of parallel computing was introduced into time series processing, and time series similarity searching algorithm based on Map/Reduce was proposed. The proposed algorithm could make use of the features of cloud computing to take large-scale computing and data processing, and could efficiently reduce the large calculation and simplify the computing process of time series similarity searching. The proposed algorithm was adopted on electrocardiograph dataset to complete similarity searching with piecewise aggregate approximation lower bound and dynamic time warping distance, which verified the effect of nodes changing on operation time and parallel speed up. Compared with the traditional one running on single PC, the proposed algorithm improved the efficiency of time series mining effectively.
    A bleeding simulation algorithm for skin surface based on improved SPH method
    WANG Na, CHEN Guodong, CHEN Yi
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  22-27.  doi:10.6040/j.issn.1672-3961.0.2015.222
    Abstract ( 946 )   HTML   PDF (1589KB) ( 579 )   Save
    References | Related Articles | Metrics
    Aiming at low dynamic model precision problem of the current blood flow realistic graphics rendering methods, a bleeding simulation algorithm for skin surface based on improved SPH method was proposed. First, some blood flow simulation algorithms were analyzed and the Casson model was selected as the fluid dynamics model of blood flow. Second, according to the characteristics of the dynamic equation of Casson fluid, the traditional SPH method was improved. Third, the improved method was used to calculate the blood flow. Finally, the obtained blood particle kinematics information was used to simulate the flow of the skin surface. The experimental results showed that the improved SPH method could reduce the complexity of the traditional method and improve the accuracy of the program, which would provide a new method for the skin incision bleeding simulation in virtual surgery.
    An improved multi-scale Graph cut algorithm
    FAN Shuyan, DING Shifei
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  28-33.  doi:10.6040/j.issn.1672-3961.1.2015.030
    Abstract ( 965 )   HTML   PDF (1635KB) ( 637 )   Save
    References | Related Articles | Metrics
    Aimed at Graph cut algorithm that has the short comings of high computational and possible aver-segmentation, a developed algorithm was presented. The algorithm used multi-scale normalized cut as an objective function of Graph cut algorithm which could avoid the over-segmentation phenomenon. Meanwhile, by combining accuracy of fine scale and easy divisibility of rough scale, sampling pixels not only retained the relationship between the original pixels, but also reduced computational complexity. By using the solving approach based on spectral graph theory, the problem was transformed into similarity matrix eigenvalue and eigenvectors problems, and the similarity was high. Experimental results showed that the proposed algorithm could effectively segment images without user interaction. The segmentation process was fast and segmentation results were accurate.
    K-Means clustering algorithm based on the Schrödinger equation
    XU Pingan, TANG Yan, SHI Jiaokai, ZHANG Huirong
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  34-41.  doi:10.6040/j.issn.1672-3961.0.2015.056
    Abstract ( 927 )   HTML   PDF (3844KB) ( 708 )   Save
    References | Related Articles | Metrics
    A new method based on the Schrödinger equation was proposed to find better initial centers. According to the values of potential energy function, initial centers could be selected. Potential energy function value was calculated for each data sample. The data sample with the minimum potential energy function value was placed in the initial cluster centers set. A distance threshold was set to compute distances between the samples from the data set and cluster centers. If a distance was greater than the threshold, this sample would be put into the cluster center and removed from the data set. Otherwise, it would be removed from the data set directly. Repeated this process until the number of initial cluster centers set was equal to K. The experimental results showed that the method could find better initial centers and achieve a higher clustering accuracy with fewer iterations. Compared with other methods, the number of iterations could be reduced about 3 times and the accuracy could be increased about 12% by using this method.
    A selective ensemble method for traveling salesman problems
    WANG Lihong, LI Qiang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  42-48.  doi:10.6040/j.issn.1672-3961.0.2015.127
    Abstract ( 878 )   HTML   PDF (1308KB) ( 490 )   Save
    References | Related Articles | Metrics
    To solve the problem of finding the optimum solution of very large TSP(traveling salesman problem), a selective ensemble method was proposed. Firstly, expanding path method was used to selective integrate some high quality solutions, and several maximum paths were obtained. And then vertex insertion method was employed to connect these paths and the remainder vertices to form a Hamiltonian tour. Finally, the tour was improved by 2-opt method. Experimental results on 5 TSP instances showed that the maximal bias was 1.69%, and the effectiveness was proved.
    Grouting technology and application of the Orientation grouting in weak area of surrounding rock tunneling
    PAN Guangming, ZHENG Dongzhu
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  49-55.  doi:10.6040/j.issn.1672-3961.0.2014.374
    Abstract ( 825 )   HTML   PDF (2207KB) ( 638 )   Save
    References | Related Articles | Metrics
    Orientation grouting technology was proposed to solve the problem of poor grouting effect and higher grouting risk of weak surrounding rock. Reliable data of intensity resistance and pressure resistance were acquired by safety experiment of orientation grouting device. The maximum grouting ending pressure, which could assure the reinforce demand of weak surrounding rock, was acquired by safety grouting ending pressure experiment. Grouting material proportioning and safety and initial setting time were acquired by initial setting time experiment of Grouting material. The results showed that the swell stopper could resist at 12 MPa grouting pressure when the safety filling pressure of swell stopper was 1.5 MPa. Under the condition of non-pressure, the cross section of grouting was 1.0~1.2 times of the cross section of grouting pipe. Safety grouting ending pressure was between initial reinforce strength and again splitting pressure, approximately 2.5~3.0 MPa. It was safe when the grouting material proportioning was between 1∶1~2∶1 and initial setting time was between 150~300 s. Orientation grouting technology could meet the safety separate-pressure demand, and controll the grouting diffusion range.
    Study on performance of electromagnetic shielding mortar mixed with copper coated fabric fiber
    ZHANG Hongbo, XIE Quanyi, YUE Hongya, MENG Qingyu
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  56-61.  doi:10.6040/j.issn.1672-3961.0.2014.313
    Abstract ( 630 )   HTML   PDF (1653KB) ( 531 )   Save
    References | Related Articles | Metrics
    In order to study the influence of fiber dosage, length and other factors on the electromagnetic shielding mortar mixed with copper coated fabric fibers mechanical properties, conductivity and SE(shielding effectiveness), strength test, resistivity test and SE test were put forth. The influence law of the variable factors to the properties of mortar with metal fiber was found. Results showed that the metal fiber could enhance the mechanical properties and electrical conductivity of mortar. The flexural strength of fiber mortar increased about 14.2% to 17.8% than ordinary mortar the compressive strength increased about 7.3%~23.1% and the electrical resistance was only 3.5% of the ordinary mortar. The high frequency electromagnetic shielding effectiveness of the mortar could be improved when adding metal fiber, shielding effect was best when the volume fraction of 2 cm thickness of mortar with metal fiber was 1%. SE was gradually increasing with the increase of fiber length, and SE of 20 mm length mortar metal fiber increased about 10 dB in 0~700 MHz and 2 000~3 000 MHz wave frequency range than ordinary mortar. Mortar thickness had an significant influence on SE, the shielding effect of 3 cm thickness mortar with metal fiber was almost 2 times of the 2 cm thickness mortar with metal fiber mortar, both of which the SE were more than 20 dB, and the maximum was 50 dB. Conclusion of this study could provide reference for electromagnetic shielding mortars popularization and application in civil architecture.
    Shear property of Yellow River's desposition in unsaturated and high plastic clay
    ZHU Xueyong, HU Wenkai, XING Qingtao, LI Peijian, SHANG Qingsen, MAN Tieqiang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  62-69.  doi:10.6040/j.issn.1672-3961.0.2015.075
    Abstract ( 689 )   HTML   PDF (2334KB) ( 620 )   Save
    References | Related Articles | Metrics
    To reveal the unsaturated soil's shear property, strength mechanism and main factors affecting them, the shear strength formula for unsaturated soil in three dimensional state was simplified as the total stress strength formula for that in two-dimensional axisymmetric stress state, and also through the unconsolidated-undrained triaxial test of Yellow River's desposition in unsaturated and high plastic clay under different moisture contents and different compactions by conventional triaxial apparatus. The test results showed that Yellow River's deposition's particle and its physical properties had their particularities: high silt containing, low plasticity and the critical range for crushing the minimum moisture content, that was, 4% higher than the best moisture content, which was the critical point for strength declining. Affected by the degree of saturation, shear property under stress was characterized by the interaction among solid, liquid and gas. The largest contribution to the shear strength of Yellow River's desposition was the matrix suction, and its shear strength was bigger than that of other unsaturated soils. The research conclusion could provide theoretical reference for the formation mechanism of the unsaturated and plastic clay's strength, and also for determining the controlling index and process of field rolling.
    Dynamic characteristic and seismic responses of steel structure of Ling-zhao Veranda in the Palace Museum
    ZHOU Qian, YAN Weiming, JI Jinbao
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  70-79.  doi:10.6040/j.issn.1672-3961.0.2014.145
    Abstract ( 691 )   HTML   PDF (4620KB) ( 532 )   Save
    References | Related Articles | Metrics
    To effectively protect Chinese historic buildings, Ling-zhao Veranda in the Palace Museum was taken as example to study dynamic characteristic and seismic responses of its steel structure by finite element analysis method. Based on damage status of steel structure as well as semi-rigid characteristic of its beam-column joints, the finite element model was built considering 3 cases. By modal analysis, its basic frequencies and main modes under different case conditions were obtained. By time-history analysis, displacement, acceleration and internal force response curves of typical nodes under 8 degree intensity of frequently occurred earthquakes were obtained, and aseismic performances of the structure under different case conditions were also discussed. Anti-collapse performance of the steel structures under 8 degree intensity of rare occurred earthquakes were discussed by spectrum response analysis. Results showed that stiffness of joints of the steel structure degenerated with its basic frequency values decreased, and its main modes changed. With the 8 degree intensity of frequently occurred earthquakes, the steel structure kept stable vibration status. Due to stiffness degradation of its joints, its peak displacement response values tended to increase, and its peak internal force values tended to decrease. All peak values were within permission scopes. When 8 degree intensity earthquakes occurred, the steel structures of different cases still remained their stability.
    Study on the effect and mechanism of oilfield produced water quality on reducing the viscosity of polymer solution
    HU Bo, WANG Fang, GAO Baoyu, XU Shiping, MA Baodong
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  80-85.  doi:10.6040/j.issn.1672-3961.0.2015.068
    Abstract ( 818 )   HTML   PDF (1666KB) ( 819 )   Save
    References | Related Articles | Metrics
    According to preparing polymer solution by oilfield produced water, the effects of Na+, K+, Ca2+, Mg2+, Fe2+ and S2-ions on the polymer solution viscosity were investigated and compared. Those ions had a negative impact on polymer solution viscosity, and meanwhile Fe2+ had the most remarkable impact. Divalent cations exerted much more effects than monovalent ones. The mechanisms of reduced HPAM viscosity were studied by IR and SEM, respectively. The results showed that Na+, K+, Ca2+ and Mg2+decreased HPAM solution viscosity by interacting with the carboxylate anions, which may lead to the polymer curl. For Fe2+, the viscosity degradation was attributed to a series of free-radical reactions, which could cause disintegration of the polymer chains and reduction of the viscosity.
    Corrosion mechanism of metal in water injection system for Shengtuo Oilfield
    SUN Limei, CUI Jie, GAO Guoqiang, LU Jianping, CEN Yuanyuan, LIU Chao, MU Xiaobin
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  86-92.  doi:10.6040/j.issn.1672-3961.0.2014.298
    Abstract ( 778 )   HTML   PDF (1304KB) ( 548 )   Save
    References | Related Articles | Metrics
    In order to lower corrosion rate of injection water and to improve injection water quality, an investigation on corrosion mechanism of metal was put forth based on analysis of attachments on metal slices and corrosive substances in injection water. The results showed that about 50% attachments(mass fraction)was water, 11%~33% was oil, and 11%~38% was inorganic solid. Hydrochloric acid-soluble inorganic solid occupied 7%~25%, which was made of corrosion products iron oxides(iron hydroxides), iron carbonate, and magnesium/calcium carbonate scales. Therefore, the corrosion was electrochemically induced by O2 and CO2, and under deposit corrosion also happened. The crude oil in injection water could accelerate corrosion indirectly. Crude oil attached to metal traps injection water to compose quiet environmental, where crystals of corrosion products and scales formed and grew up easily. Static corrosion on metal slice produced FexSy crystals, while in flowing state, Fe2+ reacted with S2- to form amorphous iron sulfur compounds, and only limited amount of SRB were found either in injection water or on metal slices, which showed that SRB was not the main corrosion factor.
    The surface enhanced Raman scattering performance of three-dimensional structures of butterfly with silver nano-particles
    LIU Deqi, ZHANG Fan, FAN Tongxiang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2016, 46(1):  93-98.  doi:10.6040/j.issn.1672-3961.0.2015.031
    Abstract ( 804 )   HTML   PDF (3204KB) ( 624 )   Save
    References | Related Articles | Metrics
    The wing scales of Papilio maackii butterflies was employed as the scaffold for arranging silver nano-particles to improve the activity of SERS. The obtained three-dimensional micro-structures roughened with silver nano-particles were characterized by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Using Rhodamine 6G(R6G)as probe molecule, the analytical enhancement factor of Papilio maackii SERS substrate was found to reach 1.57×107.FDTD calculation was conducted. The value of the log|E|2 of Papilio maackii substrate reached up to 3.85 and the reflection was 6%.The result showed that the activity of SERS could be enhanced dramatically through arranging silver nano-particles on the micro-structure of Papilio maackii butterfly scales.