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Table of Content

      
    16 June 2010
    Volume 40 Issue 3
    Articles
    3D surface reconstruction using the shape based interpolation guided by maximal discs
    QIN Tong, SUN Fengrong*, WANG Limei, WANG Qinghao, LI Xincai
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  1-5. 
    Abstract ( 332 )   PDF (1433KB) ( 1726 )   Save
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    According to existing problems of traditional shape based interpolation, a novel method of 3D surface reconstruction was proposed, that innovatively uses the shape based interpolation guided by maximal discs. The method is summarized as follows: maximal discs are determined by traversing all the pixels of distance images that are obtained using the Chamfer algorithm; after redundancy removal and projection, final discs are obtained  which are used to determine the ultimate interpolation direction with an optimized centroid formula; finally 3D surface reconstruction is achieved according to the interpolated distance values of all pixels. Simulation result showed this method could accurately implement 3D surface reconstruction.

    Structure large margin one-class classifier
    FENG Ai-min1, LIU Xue-jun1, CHEN Bin2
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  6-12. 
    Abstract ( 351 )   PDF (1033KB) ( 1561 )   Save
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    In one-class classifier(OCC)  design, considering the structure of the target data is a possible way to improve the generalization ability of the model. However, while the targets follow multicluster distributions, it is more reasonable to consider each cluster’s structure individually rather than just to treat all of them as a whole. The novel algorithm  structure large margin OCC(SLMOCC) fulfills the above strategy by restricting each data’s Mahalanobis distance to the hyperplane. Through maximizing the minimum Mahalanobis margin, SLMOCC is able to find the more reasonable optimal hyperplane attributed to its finer cluster granularity description compared with other alternatives. As for extracting the underlying data structure, this work adopts the Ward’s agglomerative hierarchical clustering on input data or data mapping in kernel space. Experimental results on toy data and UCI benchmark datasets have shown that SLMOCC outperforms  other structural OCCs.
     

    The research of a clustering algorithm based on the ant colony system
    SHA Lu1,2, BAO Pei-ming1,2*, LI Ni-ge1,2
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  13-18. 
    Abstract ( 269 )   PDF (1071KB) ( 1287 )   Save
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    For solving the problem that traditional clustering algorithms can not get good results on clustering of complex data sets, a clustering algorithm based on the ant colony system is presented. The ant’s random search is realized based on the principle that the ant leaves pheromone on its path and pursuit concentrated pheromone.  The similarity among the data is determined based on the concept of neighboring function values.  Ants establish  connections between the most similar data in the process of walking,  draw the various sub-connected graph,  and the data in the same subconnected graph are given the same cluster number. Some experiments have been made to compare the results of the proposed CAACS algorithm with those  of the DBSCAN algorithm. The experiments are based on randomly generated irregular data sets and a series of synthetic data sets. The experimental results show that the CAACS algorithm can achieve good results on complex data sets.
     

    A simulating-fishing optimization by using dynamic strategy
    WANG Yong, PANG Xing
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  19-25. 
    Abstract ( 368 )   PDF (461KB) ( 1147 )   Save
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    An improved simulating-fishing optimization method was presented to overcome the shortcomings of the existing optimization methods on using fishing strategy. A dynamic multipoint and random fishing method was used, and the different detection strategies were chosen according to the different fishing circumstances. Also, every detection area was restricted by the fisher’s current position and his moving direction. The experimental results of ten typical testing functions’ optimization show that the optimization method has the performance of  rapid convergence rate,  high accurate numerical solution and good stability.

    A kind of ant colony parameter adaptive optimization algorithm  based on particle swarm optimization thought
    XIA Hui1, WANG Hua1, CHEN Xi2
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  26-30. 
    Abstract ( 243 )   PDF (938KB) ( 1657 )   Save
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    The parameter values of the ant colony optimization (ACO) algorithm was optimized based on particle swarm optimization(PSO) thought . Through the high-quality combination of the particles search and adaptive selection of parameter values, the ACO algorithm parameter values could be selected without relying on human experience or trial and error of artificial selection. The parameter combination obtained from the algorithm could significantly improve the performance of the ACO algorithm and give parameter values in continuity, randomness and accuracy. By using the highquality combination of parameter values feedback to the ACO algorithm, this algorithm can work well in solving traveling salesman problem (TSP)  with excellent results.

    Detection and tracking of moving targets using the morphology match in radar images
    LIU Wen-liang, ZHU Wei-hong, CHEN Di, ZHANG Hong-quan
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  31-36. 
    Abstract ( 373 )   PDF (1957KB) ( 1208 )   Save
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    Moving targets detection and tracking is widely used in practice. Problems such as weak signal and severe interference of stationary objects usually occur in detecting and tracking high-speed low-altitude moving targets. Based on some aircraft landing radar echo images, a sliding window morphology match algorithm was presented to detect objects in a gray image which was processed by using frame difference. A second match algorithm was used  to find targets with a weak signal and remove false target interference.  Making a correlation between the pilot trail and the multiframe image could eliminate similar target interference of stationary objects and thus achieve the goal of tracking a moving target. The results of experiments showed that this processing algorithm is simple and has a short frameprocessing time. It can detect very weak signals, effectively suppress any interference, and quickly capture targets. This algorithm achieves real-time detection of moving objects, accurate positioning and no tracking loss.

    A wearable computing approach for hand gesture and daily activity recognition in human-robot interaction
    SHENG Wei-hua, ZHU Chun
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  37-50. 
    Abstract ( 258 )   PDF (3369KB) ( 1261 )   Save
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    Human-robot interaction (HRI) is an important topic in robotics, especially in assistive robotics. In this paper, we addressed the HRI problem in a smart assisted living (SAIL) system for elderly people, patients, and the disabled. Two problems were sloved that are very important for developing natural HRI: hand gesture recognition and daily activity recognition. For the problem of hand gesture recognition, an inertial sensor is worn on a finger of the human subject to collect hand motion data. A neural network is used for gesture spotting and a two-layer hierarchical hidden Markov model (HHMM) is applied to integrate the context information in the gesture recognition. For the problem of daily activity recognition, two inertial sensors are attached to one foot and the waist of the subject. A multi-sensor fusion scheme was developed for recognition. First, data from these two sensors are fused for coarse-grained classification. Second, the fine-grained classification module based on heuristic discrimination or hidden Markov models (HMMs) are applied to further distinguish the activities. Experiments were conducted using a prototype wearable sensor system and the obtained results proved the effectiveness and accuracy of our algorithms.

    Scheduling optimization model of refinery processes based on production characteristics
    LI Ming, LI Qi-qiang, GUO Qing-qiang, DING Ran
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  51-56. 
    Abstract ( 224 )   PDF (975KB) ( 1257 )   Save
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    The scheduling optimization problem of refinery processes was studied in view of the production characteristics such as stability and chronicity whose definitions are given first. Based on the  given definitions, production characteristics were described using disjunctive normal form and logic proposition. To evaluate production characteristics quantitatively, the performance criterion of stability and chronicity were proposed. Finally, based on expressions of production characteristics, a generalized disjunctive programming scheduling optimization model was set up. Simulation results obtained from the scheduling of a certain refinery having  expressions of production characteristics whether or not show that the scheme of the production characteristics based scheduling model can improve the performance of production characteristics and is  feasible and practical.

    Simulation and analysis of a new micro-fluidic active mixer
    XU Hao, WEI Shou-shui*, ZHANG Jing-tao
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  57-60. 
    Abstract ( 305 )   PDF (1441KB) ( 1809 )   Save
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     The model of a new piezoelectric driven micro-fluidic active mixer was constructed and simulated. The natural frequency and mode shape were obtained from modal analysis of the piezoelectric ceramic. Selecting water as the fluid, the fluidstructure interaction analysis on the mixer and its internal fluid was carried out, and the disturbance status of the piezoelectric vibrator affect on the flow in the mixer was obtained. On the premise of driven and undriven, the mixing experiments of water of different temperatures were simulated. The capability of the mixer was checked by comparing and analyzing the simulation results.
     

    Adaptive synchronous feedback control of mixed time-varying delayed and double-linked complex networks
    ZHAO Yong-qing, JIANG Ming-hui
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  61-68. 
    Abstract ( 307 )   PDF (531KB) ( 1051 )   Save
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    Based on current complex network models, a new and general double-linked complex network with time-varying delayed nodes and couplings was introduced. This model not only contains two sub-networks of different natures but also delayed nodes and couplings, and the two types of delays are both time-varying. Via the Lyapunov-Krasovskii functional method, under smaller conservative assumption and weaker requirements of the network parameters, the adaptive feedback controllers of the complex network for asymptotic synchronization and exponential synchronization were designed by using inequality. The results of numerical calculation show the effectiveness of the control methods. By giving the same initial value, it is verified that the synchronous speed of the network under exponentially synchronous control is faster.

    The development status of hot stamping and quenching of ultra high-strength steel
    LI Hui-ping, ZHAO Guo-qun, ZHANG Lei, HE Lian-fang
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  69-74. 
    Abstract ( 348 )   PDF (652KB) ( 4419 )   Save
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    Hot stamping of ultra high-strength steels (UHSS) is a new and complex forming technology integrating metal hot forming and the quenching process. UHSS has many advantages due to hot stamping, such as low flow stress, good plasticity, and high forming limit. The shape accuracy and strength of parts formed using hot stamping are very high. So the strength of hot stamping parts satisfies the requirement of auto security, although the thickness of parts is reduced. In this paper, the types of UHSS, the key technologies of hot stamping were introduced. The main content and development status of hot stamping experimental study and numerical simulation study were summarized and reviewed, and the problems at present were also commented. Also, the content for further research and study direction were prospected.

    The optimization of ultra-low sulfur steels produced by the 120t converter system in the Laiwu Iron & Steel Group
    WANG Qing-chun1, LI Mu-sen2, FAN Shu-lu3, ZHANG Ji-jun3
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  75-79. 
    Abstract ( 410 )   PDF (623KB) ( 1811 )   Save
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    Based on the thermodynamics and kinetics of desulphurization theory, an ultralow sulfur converter steelmaking process and operation system in the Laigang 120t converter system was analyzed. By controlling the converter resulfurization smelting, the deep desulfurization technological process was optimized. The results showed that the sulfur content can be reduced to below 0.005%. The desulphurization rate can be increased to 80% and therefore the final sulfur content could reach to 0.001%. Consequently, low sulfur steel with sulfur content below 0.005 % could be stably produced. In the following LF refining, SiO2 content in LF top slag could be reduced to below 8%. The final (FeO+MnO) content could be reduced to about 1% and the alkalinity can be controlled between 5 and 6.

    Research progress on mesoscale-structural simulation models of dynamic recrystallization of deformed metal during hot working
    WANG Li-jun, GUAN Xiao-jun*, YU Bao-jun, ZHAO Jian
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  80-85. 
    Abstract ( 388 )   PDF (397KB) ( 2358 )   Save
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    It is practical to simulate the mesoscale-structural evolution of dynamic recrystallization of metal materials by computer simulation to predict the material properties. The simulation techniques and research progress of the cellular automaton (CA) model and the Monte Carlo (MC) model that were used for dynamic recrystallization were reviewed. The current problems and the future directions of the Monte Carlo model for dynamic recrystallization were mainly discussed.

    Synthesis of bone-like hydroxyapatite in simulated body fluid
    ZHANG Ai-juan
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  86-90. 
    Abstract ( 335 )   PDF (973KB) ( 2820 )   Save
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    Bone-like nanograde hydroxyapatite(HAP)spicula were synthesized in simulated body fluid(SBF)by increasing the concentration of Ca and  P in the  SBF by a biomimetic method. The mass phase composition, chemical composition, micromorphology, thermal stability,  bioactivity and  high temperature  during stability at different sintering temperature 500~1300℃ of the obtained HAP were studied by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, differential thermal analysis and  atomic absorption spectrometry. The results indicated that the synthesized HAP had a  pin-like shape close to natural bone with a 70~80nm length and 10~20nm width. Though the degree of crystallization of HAP is better and better with  temperature increasing, the HAP could be decomposed when the sintering temperature is above 1000℃.The synthesized HAP powders have  good ability for inducing the deposition of Ca and P.

    Preparation and chemical modification of onion-like fullerenes with fatty acid
    YAO Yan-li, MA Guo-li
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  91-94. 
    Abstract ( 379 )   PDF (692KB) ( 973 )   Save
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    Onion-like fullerenes (OLFs) were prepared by the chemical vapor deposition(CVD) method and purified by sulfuric acid and nitric acid treatment. The surface modification of OLFs was achieved by refluxing OLFs with stearic acid (SA). The dispersion capability and stability of SA coated OLFs as a lubricant additive was also investigated. Their morphology and structure were characterized by HRTEM. Fourier transfer infrared(FT-IR) spectrum also indicated that lots of functional groups existed on the surface of purified OLFs and the surface of OLFs was coated with a modified layer of SA. The dispersion capability and stability of SA coated OLFs as a lubricant additive were effectively improved.

    Enhancement of light harvesting, luminescence and afterglow of Eu3+ doped calcium silicate through biogenic pore hierarchy
    ZHAO Qi-bin, CHOW Suk-kwun, FAN Tong-xiang, DING Jian, ZHANG Di
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  95-98. 
    Abstract ( 267 )   PDF (1021KB) ( 1252 )   Save
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    Natural microstructures in plants and animals can effectively enhance the performance of the materials, especially the hierarchical nano-porous structure, which is demonstrated to have significant positive effect on light harvesting efficiency. In order to improve the performance of calcium silicate phosphor, a leaf-templated Eu3+ doped calcium silicate phosphor was investigated with light-harvesting, luminescence and afterglow performance experiments. The results showed that the leaftemplated Eu3+ doped calcium silicate phosphor possessed a biogenic hierarchical porous structure, which is comprised of nano-pores with diameters ranging from 2.5nm, 3.0nm and 10.0~20.0nm. This structure allows a much larger surface area to interact with incident light and a higher proportion of excited Eu3+, therefore leading to enhanced light-harvesting capability in the UV-Vis range and higher light-utilization efficiency to produce stronger luminescence and prolonged afterglow.

    Monte Carlo simulation of the microstructure evolution of Al-Zn-Mg-(Sc)-(Zr) alloys during the  initial aging stage
    SUN Yuan, WANG Gui-qing
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  99-103. 
    Abstract ( 297 )   PDF (1281KB) ( 1437 )   Save
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    The Monte Carlo simulation method were applied to study  the effect of Sc and Zr on the initial aging microstructure evolution of Al-2.1Zn-1.4Mg alloy. The simulation results showed that there were Zn/Mg short range orderings in Al-2.1Zn-1.4Mg alloy during the initial aging stage. Due to  the  ‘Sc/vacancy’ mechanism, the aggregation of Zn/Mg clusters was depressed during the initial aging by adding  Sc to Al-2.1Zn-1.4Mg alloy. Addition of Zr has little effect on the size of Zn/Mg co-clusters. The addition of Sc to Al-2.1Zn-1.4Mg alloy could  induce most vacancies combining to Sc forming Sc/vacancies clusters, the remaining vacancies combined with Zr and Mg, while Zn atoms are not easy to be captured by vacancies. Mg atoms  could easily aggregate to the ‘Sc/vacancy’ clusters and then follow Zn atoms, while Zr atoms were less likely to aggregate to these clusters.

    Research status and developing trend analysis of the water inrush mechanism for underground engineering construction
    LI Li-ping1, LU Wei1,2, LI Shu-cai1, ZHANG Qing-song1, XU Zhen-hao1, SHI Shao-shuai1
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  104-112. 
    Abstract ( 375 )   PDF (1906KB) ( 2685 )   Save
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    With the developing trend of long, large and deep construction characteristics for underground engineering, larger water inrush disaster becomes the bottleneck problem for the further development of underground engineering. Based on an extensive literature review, the status and developing trend of the water inrush mechanism and countermeasures were summarized in detail, such as catastrophe condition and evolution characteristics of water inrush, formation mechanism of water inrush passage, and infestation regularity and mutation mechanism of seepage flow, based on which, a new academic idea has been proposed that artificial disturbance of excavation and disturbance of karst water and its pressure leads to water inrush of relatively intact rock masses, and the polyphyletic dynamic information of seepage mechanics for geological defects is the key for the catastrophe evolution description of geological defects. Based on  example analysis and numerical simulations, two aspects must be further studied, which are the microcosmic effect mechanism of the water inrush passage formation and macroscopic instability criterion for the system of water bearing structure considering the effect of geological factors and engineering effort factor, and the geophysical method effectiveness for the water bearing structure diction can be improved by combining with the monitoring method of polyphyletic information for water inrush prediction, which will lay a theoretical basis for the groundwater inrush prediction in underground engineering.

    A genetic neural network model based on a trend examination method and engineering application
    QIU Dao-hong1, ZHANG Le-wen1, CUI Wei2, SU Mao-xin1, SUN Huai-feng1
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  113-118. 
    Abstract ( 257 )   PDF (490KB) ( 987 )   Save
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    Aiming at the model’s reliability problem of a neural network, a trend examination method was presented to check the model’s reliability. It checked the model through the influence trend of evaluation index to evaluation grade. The process of the method was  incessantly adjusting the model’s parameter, training, and trend examination, until  the best model was obtained. This method  presented  a new idea and can be used in any problems of model’s reliability examination based on the foreknowable experience method. To the problem of the contribution difference of samples, the method of weighted samples was used to preprocess the samples and the samples weight was used in the objective function of the neural network. Finally, a genetic algorithm was adopted to optimize the parameter of the  neural network and a GAANN model based on the trend examination method was established. The improved model was applied to practical engineering about surrounding rock classification and the results showed that this method can improve the neural network generalization ability and prediction accuracy.

    Application of the metabolic GM(1,1)  model in forecast of buildings subsidence
    BIAN Pei-song1, WANG Deng-jie1, YU Shao-hua2
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  119-123. 
    Abstract ( 326 )   PDF (352KB) ( 1371 )   Save
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    In subsidence forecast, after using MATLAB7.0 to make original data to be equal interval and the building differential model through cumulative series and original series, by being based on engineering mathematics and using the grey theory, the metabolic GM(1,1) model was established with the old data being removed when new data was added in. The effect of simulation and prediction was checked relying on an engineering example and was compared with the general GM (1,1) model and the new information GM (1,1) model.Calculation and comparison results showed that the metabolic GM (1,1) model has higher accuracy than other models and forecast effects are greatly increased.

    Experiments and calculating method for cracking strength and crack width of the metro segment
    ZHOU Hai-ying1, LI Li-xin2, CHEN Ting-guo1
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  124-127. 
    Abstract ( 393 )   PDF (692KB) ( 1792 )   Save
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    To investigate the cracking behavior of the reinforced concrete (RC) lining segment, a test of two RC lining segments of fullscale with different reinforcement ratios was carried out. Through the analysis, it was found that  increasing the  reinforcement ratio has little effect on cracking strength of the RC lining segment, the average crack spacing and the maximum crack width of RC lining segment decreases at a small rate with the increasing of the reinforcement ratio. The effect of different reinforcement ratios on cracking strength and crack  width of the RC lining segment was analyzed based on the test results. Formulas for cracking strength considering height and maximum crack width as well as  reinforcement ratio are proposed, and the results calculated by formulas show good agreement with those of experiments.
     

    Study of the anchoring parameter for the hybrid bonding of FRP
    GUAN Yan-hua1,2, MIAO Hai-tao2, SONG Xiu-guang2
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  128-132. 
    Abstract ( 284 )   PDF (1268KB) ( 1645 )   Save
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    To define the norms of the special mechanical anchors and direct the design and the construction of hybrid bonded fiber reinforced polymer(HB-FRP), the specimens were investigated in a drawing test program in order to study the anchor depth of screw bolts. The finite element analysis was conducted to simulate the contact compression stress on the basis of different sizes of steel plate and bolt prestress by the Pretension 179 element and compact pairs of ANSYS. On the basis of experiments, the formula for calculating anchor depth of screw bolts is put forward. A method was suggested to guide the designs and the choice of the steel plates on the basis of the finite element analysis. It contributes to direct the design and the construction of HB-FRP.

    Study on application of porous andesite in asphalt pavement
    GUO De-dong1,2, XU Hong-mei3, LI Xiao-gang4
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  133-136. 
    Abstract ( 346 )   PDF (336KB) ( 1515 )   Save
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    Three kinds of asphalt immersion methods (aggregate immersion method, aggregate mixture immersion method, and asphalt mixture immersion method) and calculation methods were used to test the maximum theoretical relative density of the asphalt mixture. Mix ratio design was carried out to determine the optimal asphalt content and all the pavement performances of asphalt mixtures were compared and analyzed. The general water stability property tests and HWTD were used to test the water stability of three kinds of andesite asphalt mixtures which added with no antistripping agent, liquid antistripping agent and hydrated lime. The results showed  that the pavement performance of asphalt mixtures, which were  manufactured by using the asphalt immersion method to determine the maximum theoretical relative density of asphalt mixture and carry out the mix design, is better than that of the asphalt mixture manufactured by using the calculation method; and HWTD could effectively evaluate the water stability property of asphalt mixtures . Adding hydrated lime is the optimum measure to improve the water stability property of andesite asphalt pavement.

    A RBAC access control model based on autonomy domain
    LONG Jun, ZENG Xiao-sa, ZHANG Zu-ping
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  137-142. 
    Abstract ( 307 )   PDF (599KB) ( 1393 )   Save
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    As the traditional role-based access control (RBAC) models have shortcomings when applied in lager-scale enterprise applications, an improved RBAC model based on autonomy domain (AD-RBAC) is proposed. This model introduces ‘autonomy domain’ to describe the organization structure; divides groups into administrative group and common group, which enhances the expression capability of the group; adopts organization structure domain description model to construct group hierarchy and group types. All these contribute to the simple and intuitive realization of multilevel user authorization management. In the expert information service grid, AD-RBAC is used to achieve authorized service and data access of grid nodes based on virtual domain, which proves the feasibility and effectiveness of this model.
     

    A wireless sensor node localization algorithm
    XIA Shao-bo1, XU E2
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  143-147. 
    Abstract ( 313 )   PDF (391KB) ( 1491 )   Save
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     A DV-Hop localization algorithm from the basis of difference is proposed, which is specific to questions of node localization algorithm in a wireless sensor network (WSN) system. The beacon node surveyed the positioning error and took the correct value of the regional broadcast. After the unknown node received the adjustment information from the beacon node,  it revised its own relative position reckoning value to reduce the node position error and to enhance the precision of the localization algorithm. Simulation tests show that, compared with the ordinary DV-Hop  algorithm, this algorithm gets distinct improvement from performance indices between the position error and communication distance ratio.

    Experimental study on  chip geometry and size effect in micro-cutting aluminum 7050-T7451
    ZHOU Jun1,2, LI Jian-feng1,2, SUN Jie1,2
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  148-153. 
    Abstract ( 331 )   PDF (2049KB) ( 1973 )   Save
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    The micro-scale machining characteristics of a non-ferrous structural alloy aluminum 7050-T7451 were investigated through a series of orthogonal cutting experiments. A carbide tool was used and the effect of cutting edge radius was considered. The workpiece was prepared as  thin wafers so that  orthogonal turning experiments could be conducted on the NC milling center. Different cutting speeds and various depths of cut were adopted in the single factor cutting experiments.  Chips under different cutting parameters were collected for the investigation of  chip geometry. The effect of cutting parameters and cutting edge radius on chip thickness and curls were investigated. The cutting forces were measured with the  Kistler 9257B dynamometer. The characteristic of cutting forces and thrust forces were analyzed via considering the effect of cutting edge radius and the effects of cutting speed and depth of cut on cutting forces and size effect in orthogonal micro-scale cutting of Al 7075-T7451 were presented.
     

    Simulation and optimization on ethyl acetate producing batch reactive distillation
    FENG Zhen-heng, ZHANG Zhong-cheng
    JOURNAL OF SHANDONG UNIVERSITY (ENGINEERING SCIENCE). 2010, 40(3):  154-158. 
    Abstract ( 402 )   PDF (688KB) ( 2254 )   Save
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    To get the optimum technological condition of the preparation of ethyl acetate from acetic acid and ethanol, based on  experimental data, the experiment was simulated and optimized by using Aspen Plus, a simulation software of chemical technology using the NRTL activity coefficient model and the HaydenO′Connell equation of the gas state.The parameters of the reflux ratio, heating temperature and the feed molar ratio of ethanol to acetic acid were optimized. Under these optimized conditions,the reflux ratio was 5.1, the heating temperature was 120℃,  and the feed molar ratio of ethanol to acetic acid was 1.04∶1.00. Simulated with Aspen Plus, the mass fraction of ethyl acetate in distillate reached 82.13%. Based on these optimized conditions, the improvement on the experimental conditions, the mass fraction of ethyl acetate in the distillate  increased from   79.45% to 81.95%,  which proved the reliability of the simulation and optimization.