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    15 November 2010, Volume 31 Issue 11 Previous Issue    Next Issue

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    OriginalPaper
    Analysis of vibration signal of wet ball mill shell and soft sensoring for mill load
    Tang, Jian (1); Zhao, Li-Jie (1); Yue, Heng (1); Chai, Tian-You (1)
    2010, 31 (11):  1521-1524.  DOI: -
    Abstract ( 333 )   HTML   PDF (1408KB) ( 626 )  
    It is difficult to detect the mill load (ML) efficiently in the ore milling process of a ball mill and the mill is often underloading, thus causing the difficulty in implementing the optimal control with energy saving and cost reduction. To solve the problems, how the vibration of mill shell is generated is analyzed, as well as the power spectrum density (PSD) of the vibration signals under different milling conditions and the correlation between the PSD and ML parameters within different frequency bands. Then, the way to model the soft sensoring is proposed introducing the three ML parameters, i.e., the mineral to ball volume ratio in a mill, pulp density and charge volume ratio. With the vibration acceleration signals of the mill shell in time domain transformed into frequency domain by fast Fourier transform (FFT), the principal component analysis (PCA) is used for dimensionality reduction and extraction of the principal components (PCs) of characteristic spectra within the low, medium and high frequency bands separately. Finally, the least square support vector machines (LSSVM) are used to implement the mapping between characteristic spectral PCs and ML parameters. Experimental results showed that the way by FFT-PCA-LSSVM can extract the spectral characteristics efficiently with higher prediction accuracy than other conventional methods.
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    Research on the molten iron scheduling system oriented to iron-steel correspondence and its application
    Huang, Hui (1); Chai, Tian-You (1); Zheng, Bing-Lin (1); Luo, Xiao-Chuan (1)
    2010, 31 (11):  1525-1529.  DOI: -
    Abstract ( 339 )   HTML   PDF (2306KB) ( 894 )  
    Based on the detailed analysis of existing molten iron scheduling and the envision for hierarchical system structure, an scheduling strategy with integrated systematic framework was presented to balance the molten iron supply and steelmaking demand, where the case knowledge, data, mathematic model and man-machine interaction were all taken into account. The functions of the key problems in molten iron scheduling and the real-time solutions to them were discussed in detail, as well as the structure and function of the software system used, which has been applied successfully in a large-scale iron and steel complex in China.
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    Particle swarm optimization based on mutation strategy
    Gao, Li-Qun (1); Wu, Pei-Feng (1); Zou, De-Xuan (1)
    2010, 31 (11):  1530-1533.  DOI: -
    Abstract ( 441 )   HTML   PDF (1257KB) ( 771 )  
    After studying the features of PSO (particle swarm optimization), the mutation factor was integrated into the algorithm to form its new version, i.e., the mutational particle swarm optimization (MPSO) in which a mutation strategy was incorporated. With the mutation factor the algorithm can improve the developability of solution space so as to decrease the possibility that the PSO falls into local optima. The tested results of four well-known unconstrained benchmark optimization problems, a constrained problem and an actual application problem revealed that MPSO can successfully tackle both the high-dimensional unconstrained problems and the high-dimensional problems with linear constraints. Moreover, MPSO as a promising optimization algorithm has strong convergence and high stability.
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    A global harmony search algorithm and its application to PID control
    Zou, De-Xuan (1); Gao, Li-Qun (1); Wu, Pei-Feng (1); Wu, Jian-Hua (1)
    2010, 31 (11):  1534-1537.  DOI: -
    Abstract ( 272 )   HTML   PDF (1429KB) ( 620 )  
    Restricted by the multi-function H criterion, the PID control is essentially a constrained optimization problem. A global harmony search (GHS) algorithm is introduced to solve the problem since GHS has strong convergence and the capability of getting rid of the local optimum due to the utilization of position updating and mutation with low probability. Then, the contradiction between objective and constraint can be settled by combining GHS with a penalty function. Experimental results showed that the GHS algorithm has a high developability to solve the spatial problems of PID control, and that the solutions by GHS are better than the other ones in earlier work.
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    Adaptive differential evolution algorithm based on multiple subpopulation with parallel policy
    Lu, Feng (1); Gao, Li-Qun (1)
    2010, 31 (11):  1538-1541.  DOI: -
    Abstract ( 211 )   HTML   PDF (1082KB) ( 1031 )  
    Analyzing the attributes of classic and modified mutation operators and the statistical information on population, all of the individuals is classified into different subpopulation according to the difference between individual adaptability and different mutation operators are introduced according to the different values of individual adaptability so as to get rid of the local optima efficiently with convergence rate expedited. Based on the empirical values of control parameters, the parameters are adjusted adaptively to balance the global and local search capability in an algorithm. The simulation results of 13 standard test functions showed that the algorithm proposed is more effective in comparison with other algorithms.
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    Adaptive H control of voltage PWM rectifier for microturbine power generation
    Yan, Shi-Jie (1); Wang, Xu (1); Liu, Xiu-Chong (1); Zhang, Xue (1)
    2010, 31 (11):  1542-1545.  DOI: -
    Abstract ( 212 )   HTML   PDF (565KB) ( 557 )  
    Analyzing the operating principle of PWM rectifier and the model of a permanent magnetic synchronous generator in a microturbine power generation system, a model of PWM rectifier was developed with a power control system provided theoretically on the basis of active/reactive power. Considering the low capacity of the power generation system and the wide fluctuations of uncertain loading, an adaptive control strategy for DC-controlled voltage was proposed on power control basis. Then, the stable DC-controlled voltage and high power factor will both be implemented in the sense of Lyapunov stability via the auto compensation for loading change. Simulation and test results both showed that the adaptive control can make the fluctuations of DC-controlled voltage in narrow range with high power factor provided, thus verifying the effectiveness and practicability of the strategy proposed.
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    Nonlinear adaptive PID decoupling controller based on multiple models
    Li, Lei (1); Mao, Zhi-Zhong (1); Liu, Fang (1)
    2010, 31 (11):  1546-1549.  DOI: -
    Abstract ( 244 )   HTML   PDF (1457KB) ( 711 )  
    For a class of nonlinear discrete-time systems with strong coupling, a multivariable adaptive PID decoupling control strategy based on multiple models is proposed without the balance point parameters of the systems as given conditions. It consists of a fully adaptive PID decoupling controller, a parameter-reassigned adaptive PID decoupling controller and a set of parameter-fixed PID decoupling controllers, and a switching mechanism. Theoretical analysis showed that among the three different kinds of decoupling controllers the first one can guarantee the bounded-input-output(BIBO) stability for the closed-loop-system and the rest used to improve the system performance via choosing the switching functions rationally.
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    On the optimal control of active vibration of a smart piezoelectric cantilever beam
    Chen, Zhen (1); Xue, Ding-Yu (1); Hao, Li-Na (1); Xu, Xin-He (1)
    2010, 31 (11):  1550-1553.  DOI: -
    Abstract ( 334 )   HTML   PDF (1637KB) ( 628 )  
    The cantilever beam which is made from the smart piezoelectric material PVDF as sensor and IPMC as actuator was investigated, with the sensoring and actuating equation both given relevantly. Then, they were transformed into the state space equations via modal analysis, thus designing a vibration control system for the smart piezoelectric cantilever beam. Combining the genetic algorithm with LQR optimal control to design the weighted matrices Q and R, the control ratio of state feedback can be obtained so as to investigate the optimal control of the active vibration of a smart piezoelectric cantilever beam. Simulation results verified that the control system is good for vibration abatement.
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    Study on soft sensoring of electrolyte composition based on intelligent computation
    Wang, Xiao-Gang (1); Li, Chun-Bai (1); Hu, Lun (2)
    2010, 31 (11):  1554-1557.  DOI: -
    Abstract ( 282 )   HTML   PDF (1228KB) ( 419 )  
    To achieve the online real-time compositional analysis of the electrolyte for the production of electrolytic copper, a soft sensoring technique was proposed for the compositional analysis according to the electrochemical reaction mechanism and production process data of electrolytic copper, based on the improved selection strategy of hidden nodes in neural network and optimized training algorithm. Simulation results showed that the soft sensoring technique proposed is good at data fitting and generalizability. Furthermore, the in-situ running results also showed that the technique can predict accurately the electrolyte composition in time in accordance to the actual change in the electrolytic process.
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    Research of software network measurement based on the deviation of standard entropy
    Li, Peng (1); Zhao, Hai (1); Li, Hui (1); Liu, Zheng (1)
    2010, 31 (11):  1558-1561.  DOI: -
    Abstract ( 231 )   HTML   PDF (567KB) ( 561 )  
    Based on the characteristics of the macro-topology eigenvalues of a software network, the deviation ratio of eigenvalues of a software network, the software quality relative to its scale and the structural orderliness of software are defined conceptually. With the difference between the eigenvalues of software network and the mean value of eigenvalues of the open-source software which is widely used at present on the same scale was measured by the deviation ratio of standard entropy, how the eigenvalues affect the orderliness relative to the scale of relevant software are revealed. Verifying the deviation ratio of standard entropy via a single-sample K-S test, a conclusion is drawn that when the deviation of standard entropy is greater than 0.05, the software has certain problems in system design and encoding, and there is plenty of room for improvement in the orderliness relative to the structural scale of software.
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    Research on structural holes and closeness of software network
    Xu, Jiu-Qiang (1); Liu, Hong (1); Zhao, Hai (1); Yu, Shuang (1)
    2010, 31 (11):  1562-1565.  DOI: -
    Abstract ( 171 )   HTML   PDF (1335KB) ( 602 )  
    To solve the problem that the conventional methods cannot metrize the large-scale softwares effectively, the structural holes and closeness in a complex network were studied interdisciplinary to quantify the software metrization. The two eigenvalues were calculated statistically so as to fit the degree of software network relationally. It was found that the relation between the degree and structural holes in a software system presents a power function curve while the relation between the degree and its closeness presents a trapezoidal distribution. Therefore, introducing the structural holes and closeness as reference eigenvalues into a software network is available to quantify the dependence and the degree of centralization of the nodes in the software network.
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    MVC-based transmission algorithm of adaptive tracing for real-time streaming media
    Zou, Yong (1); Zhao, Hai (1); Zhao, Ming (1); Song, Chun-He (1)
    2010, 31 (11):  1566-1569.  DOI: -
    Abstract ( 298 )   HTML   PDF (990KB) ( 610 )  
    To guarantee the synchronization performance of a constrained real-time streaming medium system and settle the contradiction between synchronization and playback delay on the basis of buffer maximization, a dynamic method to determine the setpoint of buffer occupation was proposed and used in the simulation as the setpoint for the medium streaming rate control system. To eliminate the overshoot by way of conventional control, the MVC was chosen to design a transmission algorithm of adaptive tracing with buffer setpoint for a real-time streaming medium. Simulation results showed that the algorithm proposed can adaptively compute the proper setpoint of buffer occupation with any network delay and implement the tracing of dynamic setpoint, thus providing the playback with highly real-time performance.
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    Robust constrained least squares constant modulus algorithm
    Song, Xin (1); Wang, Jin-Kuan (1); Han, Ying-Hua (1); Wang, Bin (2)
    2010, 31 (11):  1570-1573.  DOI: -
    Abstract ( 243 )   HTML   PDF (736KB) ( 567 )  
    During the actual communication practice, the performance of linearly constrained least squares constant modulus algorithm (LC-LSCMA) will deteriorate acutely due to signal steering vector mismatches. A novel approach, i.e., the robust constrained LSCMA, is therefore proposed the way the recursion formula of weight vector is deduced under the condition that the modulus involving mismatched directional vector is constrained and the condition is included in the cost function so as to improve the robustness of LSCMA. Besides, the complexity of computation can be reduced by introducing the recursive algorithm to compute the inverse matrix. The robust constrained LSCMA provides a high robustness against signal steering vector mismatches, thus enabling the SINR of array output to approximate to its optimal value. Simulation results show that the performance of the proposed algorithm is superior to the conventional algorithm and more adaptable to the actual complex communication.
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    A trust model with multidimensional factor for P2P routing
    Tan, Zhen-Hua (1); Cheng, Wei (1); Zhu, Zhi-Liang (1); Wang, Xing-Wei (2)
    2010, 31 (11):  1574-1577.  DOI: -
    Abstract ( 214 )   HTML   PDF (1213KB) ( 498 )  
    To solve the problem that the anonymity and concealment of P2P nodes are liable to bring on vicious nodes, a new distributed trust model named MFTrust was developed on some social network principles for P2P networks. Both global and local trust models were developed involving such multidimensional factors as time, measure of success in transmission transmitting frequency and appraisals for relevant nodes. Designing the historical correlation factor of communication between nodes and based on the global trustiness, a correlation trust model was developed. Simulative analysis showed that the MFTrust model is quicker at trust convergence rate than conventional local and global trust models and available to distinguish the attack from vicious nodes effectively during routing.
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    Secure cluster-based group key protocol in Ad Hoc networks
    Zhang, Ying (1); Li, Hui (1); Zhou, Fu-Cai (1); Chang, Gui-Ran (1)
    2010, 31 (11):  1578-1581.  DOI: -
    Abstract ( 247 )   HTML   PDF (1031KB) ( 762 )  
    The Joux protocol isn't secure from active attack in Ad Hoc networks. A cluster-based private key protocol for secure multicast is therefore proposed to solve the problem, where an identity-based public key system with timestamp is applied to the authentication of any cluster members instead of CA (center of authentication). Security analysis showed that the protocol is highly secure against both the active and passive attacks in Ad Hoc networks and enables the group key consultation securely. Performance analysis showed that, in comparison with the application of CA, the protocol reduces the costs involved in communication rounds/frequency, radio frequency and total number of messages/computations(such as the operations of point multiplication, matching and exponentiation).
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    Hot deformation behavior of high-manganese TRIP steel
    Zhang, Wei-Na (1); Liu, Zhen-Yu (1); Wang, Guo-Dong (1)
    2010, 31 (11):  1582-1585.  DOI: -
    Abstract ( 292 )   HTML   PDF (2394KB) ( 494 )  
    The hot deformation behavior and microstructure evolution of high-manganese TRIP (transformation induced plasticity) steel(Fe15Mn3Si3Al) were investigated via hot compression test in a temperature range from 800 to 1050°C and strain rate ranging from 0.01 to 5.0 s-1. The effects of temperature, strain rate and true strain on the flow behavior and microstructure of the steel were discussed. The results showed that the dynamic recrystallization occurs only at higher temperature and lower strain rate. Hot deformation behavior of the steel specimens is sensitive to temperature and strain rate, while the strain rate affects the hot deformation behavior greatly. The apparent stress exponent and the apparent activation energy of the specimens are 3.909 and 353.167 kJ/mol, respectively. With the experimental data, the hot working equation of the steel is given.
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    Seasonal performance of water-in-glass evacuated tubes
    Li, Bao-Kuan (1); Song, Yang (1); Shonhiwa, Chipo (1); Wang, Fang (1)
    2010, 31 (11):  1586-1589.  DOI: -
    Abstract ( 383 )   HTML   PDF (2161KB) ( 981 )  
    A computational model of water-in-glass evacuated solar heater was developed through the commercial software Fluent, and the UDF was introduced to analyze the performance of the heater with all the four seasons considered. In the analysis the effects of the apparent daily/seasonal movement of the sun on the angle of incidence and of the quantity of radiation on the evacuated tube collector were both taken into account. Compared with the experiment results, the numerical simulation results showed the goodness of fit. A conclusion was therefore drawn that the water temperature increases quickly in summer but slowly in winter and that the hot water supplied in this way can meet fully the household requirements of hot water in summer, spring or autumn. A foundation is then laid down for further study to design a new system for supplying the water at higher temperatures even if in winter.
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    Effect of Acidithiobacillus ferrooxidans on leaching out chalcopyrite and pentlandite
    Tong, Lin-Lin (1); Yang, Hong-Ying (1); Zhang, Yao (1); Zhang, Gu-Ping (1)
    2010, 31 (11):  1592-1593.  DOI: -
    Abstract ( 251 )   HTML   PDF (1581KB) ( 591 )  
    The effect of Acidithiobacillus ferrooxidans on leaching out chalcopyrite and pentlandite was studied and it was found that the leaching rates of chalcopyrite and pentlandite in such a case are 2.41 times and 1.91 times greater than the rates in aspect system, respectively. It meant that the bacteria plays an important stimulating role in the leaching out process of the two minerals, where the yellow jarosite (K[Fe3(SO4)2(OH)6]) precipitates and forms and is adsorbed onto the mineral surface, i.e., a passivation. The oxidation of the minerals is thus hindered severely.
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    Reliability-based sensitivity analysis of mechanical strength via quasi-Monte Carlo method
    Zhang, Yan-Lin (1); Zhu, Li-Sha (1); Zhang, Yi-Min (1); Zhang, Yan-Fang (2)
    2010, 31 (11):  1594-1598.  DOI: -
    Abstract ( 343 )   HTML   PDF (1912KB) ( 1158 )  
    Although the program structure of the Monte Carlo method is simple and bears no relation to the computational efficiency and dimensionality of the problems to be studied, lots of samples are needed to get precise results because the structural failure probability is often very small, and the computational efficiency is therefore reduced. For this reason, the quasi-Monte Carlo (QMC) method is proposed introducing the Halton sequence instead of the pseudorandom numbers to compute the reliability-based sensitivity, combining it with the importance method. The QMC method can reduce obviously the number of samples, in comparison with conventional MC method, with the computational efficiency improved and the errors definitely given. The superiority of the QMC method in computational efficiency has been verified via the analyses of the contact fatigue reliability of a gear and its reliability-based sensitivity.
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    An approach to reliability-based risk assessment of crackable structures
    Lu, Hao (1); Zhu, Li-Sha (1); Zhang, Yi-Min (1)
    2010, 31 (11):  1599-1602.  DOI: -
    Abstract ( 250 )   HTML   PDF (1757KB) ( 492 )  
    For the structures with uncertain parameters, it is essential to finding out the relationship between design parameters and reliability, so as to optimize the design parameters in accordance to the required target reliability index. An approach to the reliability-based risk assessment of crackable structures was therefore proposed. Based on the partial factors, a check formula was derived for the design parameters in relation to the target reliability index, thus enabling the parameters in design to meet the requirement of reliability. Further, the proposed method could be applied to the exploration of the structure reliability problem caused by crack propagation.
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    A modified formula of reliability-based sensitivity calculation on the basis of stochastic perturbation theory
    Zhu, Li-Sha (1); Zhang, Yi-Min (1); Tang, Le (1); Li, He (1)
    2010, 31 (11):  1603-1606.  DOI: -
    Abstract ( 346 )   HTML   PDF (2311KB) ( 600 )  
    To solve well the problem of reliability of a nonlinear system in engineering practice, the design of reliability is theoretically combined with sensitivity analysis on the basis of the stochastic perturbation theory of reliability design to modify the formula to compute the reliability-based sensitivity with normally distributed stochastic parameters, thus making the modified computing formula more adaptable to the nonlinear structural system in engineering practice. With the parameterized computation program provided, the relationship between structural reliability and the mean value of basic random variables is given. A numerical example verifies that the computational accuracy of the sensitivity based on structural reliability to the mean value of basic random variables is greatly improved by the modified formula referring to the highly nonlinear ultimate state equations, with a more exact reference provided theoretically for engineering practice.
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    Dynamic analysis of a 3-DOF parallel manipulator
    Li, Bing (1); Zhang, Yu (1); Xie, Li-Yang (1); Wei, Yu-Lan (1)
    2010, 31 (11):  1607-1610.  DOI: -
    Abstract ( 440 )   HTML   PDF (1857KB) ( 632 )  
    The structural system of a 3-DOF flexible parallel manipulator is described, to which both the fixed and motional coordinate systems are set up. The dynamic characteristics of the manipulator are analyzed by FEM and bending vibration method, thus obtaining the dynamic equation based on the bending vibration theory and comparing it with the dynamic characteristics based on modal assumption. The resonant frequency and damping ratio of the manipulator are obtained via an experimental system for the manipulator, with the resonance mode discussed. The natural frequencies calculated by FEM, bending vibration and modal assumption are compared with the experimental value separately, and the results showed that the natural frequency obtained by modal assumption is closest to the experimental value.
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    Vibration reduction of mistuned blade-disc by ant colony algorithm and modal localization parameter
    Yuan, Hui-Qun (1); Yang, Shao-Ming (1); Wu, Zhen-Yu (2); Zhang, Lian-Xiang (3)
    2010, 31 (11):  1611-1614.  DOI: -
    Abstract ( 352 )   HTML   PDF (1799KB) ( 547 )  
    A typical model of lumped parameters of blade-disc structure was developed to solve the problems of the difficult post-processing for the superstandard vibration of aero-engine caused by mistuned blade-disc structure. The effect of the sequential arrangements of mistuned blades on modal localization was studied, and the ant colony optimization technique was applied to the optimal design of positioning every blade. Simulation results showed that for the definite mistuned blades the different sequential arrangements will affect the inherent characteristics of the blade disc system very greatly and, simultaneously, verified that the ant colony algorithm can provide the sequential arrangements of blades quickly and accurately so as to improve obviously the modal localization of the blade disc, thus providing an efficient way available to the trouble-shooting of the blade disc system.
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    Dynamical analysis of anti-resonance vibrating machine under material impact
    Jiao, Chun-Wang (1); Liu, Jie (1); Wang, Fu-Bin (1); Zhang, Jin-Ping (2)
    2010, 31 (11):  1615-1618.  DOI: -
    Abstract ( 289 )   HTML   PDF (2084KB) ( 492 )  
    The mode of material's movement and how it acts onto its upper body were investigated. A comprehensive dynamic model of anti-resonance vibrating machine was developed taking the impact of conveying material onto the upper body into account. The harmonic balance method was used to solve the nonlinear system dynamic equations, and an amplitude-frequency response curve of the dynamic amplification factors of both upper and lower bodies was obtained. Furthermore, a numeric simulation was done according to the parameters obtained from a testing bench, thus obtaining a displacement-time response curve of both upper and lower bodies. The results showed that the anti-resonance frequency decreases while the vibration amplitudes of both the bodies increase in the vicinity of the anti-resonance point compared with the material impact is considered.
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    Strip steel surface bright/dark field defect image registration combined with neighborhood information
    Wei, Yu-Lan (1); Yan, Yun-Hui (1); Li, Bing (1); Dong, De-Wei (1)
    2010, 31 (11):  1619-1622.  DOI: -
    Abstract ( 289 )   HTML   PDF (1545KB) ( 572 )  
    To get rid of the displacement and rotation as shown in the two strip steel surface defect images at the same position, which are obtained by the detection system for both bright and dark fields, and denoise the images detected during strip vibration and in-situ production process, a new mutual-information-based registration of images was proposed combining the pixel spaces in neighborhood with grey level data. During the computation of the mutual-information-based registration of images, the grey level of every pixel is determined together with the grey level of a pixel in its neighborhood, which distributes the different weights according to the relationship between distance and grey level. Experimental results showed that the accuracy of the new method of registration can meet fully the requirements for strip steel defect detection and reduce effectively the impact of noise on registration accuracy, thus laying a foundation to identify the strip surface defects and evaluate the strip quality.
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    Effect of accumulators on reducing fluid pulsation on a solenoid value test bed
    Guo, Bei-Tao (1); Liu, Hong-Yi (1); Wang, Fei (1); Luo, Zhong (1)
    2010, 31 (11):  1623-1627.  DOI: -
    Abstract ( 330 )   HTML   PDF (2153KB) ( 646 )  
    Describing the structure of fluid system on a solenoid valve test bed, the mechanism which induces the fluid pulsation and the damages to the normal operation of the test bed were discussed to reveal the necessity to explain the reasons why the fluid pulsation should be investigated and reduced by some technical measures to take. A group of accumulators was applied to the fluid system on solenoid valve test bed so as to reduce the fluid pulsation, with the construction and working principle of accumulator described. Furthermore, the effect of pressure of the fluid system in combination with accumulators on the amplitude-frequency characteristics of pumped flow pulsation and its dynamic behavior were investigated via simulation. Then, the related parameters were chosen rationally to optimize the reduction of the fluid pulsation.
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    Reconstruction surgery of defective mandibule by the aid of rapid prototyping technique
    Wu, Wen-Zheng (1); Qin, Xing-Jun (2); Cui, Kun-Peng (1); Wang, Wan-Shan (1)
    2010, 31 (11):  1628-1631.  DOI: -
    Abstract ( 253 )   HTML   PDF (1315KB) ( 662 )  
    To perfect the traditional surgery and postoperational figuration in reconstruction surgery of defective mandibule with the autologous fibula flap used, a rapid prototyping (RP) model for customized mandible was developed on the basis of patient's CT data to simulate the result of the reconstruction surgery. According to the model, a piece of titanium plate was shaped before the surgery as the outline template for the mandible during operation. With the RP model applied to mandibule, the figuration precision of reconstructed mandible was improved greatly and, especially, the original fibular shaping time 4~5 hr was shortened to 1.0~1.5 hr, i.e., the whole operating time decreased to a great extent. The RP technique is therefore proved worthy to extend for the reconstruction surgery of defective mendibule.
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    Application of N-laurel-1, 3-diaminopropanes as collector in reverse flotation of hematite
    Liu, Wen-Gang (1); Wei, De-Zhou (1); Gao, Shu-Ling (1); Cui, Bao-Yu (1)
    2010, 31 (11):  1632-1635+1639.  DOI: -
    Abstract ( 388 )   HTML   PDF (1985KB) ( 788 )  
    The flotation capability of N-laurel-1, 3-diaminopropanes (ND13) for hematite and quartz were studied in laboratory via single mineral flotation and the results showed that ND13 has high catchability to quartz, i.e., when the concentration of collector is 50 mg/L with the pH value of pulp 7~10, the recovery of quartz is over 93%. The flotation test results of manually mixed ore samples where the mass ratio of hematite to quartz is 1:1 with iron grade 35% showed that ND13 can separate hematite from quartz better, i.e., the iron recovery from ore concentrate is 86.35% the iron grade of ore concentrate 62.78% and that of tailings 9.21% if the concentration of ND13 is 66.7 mg/L and that of starch 6.67 mg/L with pH value 7.27. The analysis of zeta-potentials and IR spectra indicated that both the electrostatic adsorption and hydrogen bonding adsorption take place between ND13 and minerals surfaces.
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    Preparation integrated with stabilization for hemihydrate calcium sulfate whiskers
    Yuan, Zhi-Tao (1); Wang, Yu-Bin (2); Li, Li-Xia (1); Han, Yue-Xin (1)
    2010, 31 (11):  1636-1639.  DOI: -
    Abstract ( 384 )   HTML   PDF (1351KB) ( 678 )  
    The preparation process of hemihydrate calcium sulfate whiskers with optimized stabilizer was integrated with stabilization to investigate the effects of additive quantity of stabilizer on the morphology and stability of the crystal whiskers. Characterized by SEM and XRD, the results showed that the morphology of the whiskers can be stabilized by adding 0.025% sodium oleate in preparation process and, after 72 hr, their chemical composition turns statically into dihydrate calcium sulfate. However, the preparation integrated with stabilization for hemihydrate calcium sulfate whiskers, i.e., both the morphology and chemical composition are stabilized can be implemented by the way 0.025% sodium stearate is added in preparation with 0.15% sodium oleate added after preparation.
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    A method for total microbial DNA extraction directly meeting the requirement of PCR amplification from an Aeolian sandy soil
    Zhang, Ying (1); Cao, Cheng-You (1)
    2010, 31 (11):  1640-1643.  DOI: -
    Abstract ( 316 )   HTML   PDF (1556KB) ( 639 )  
    The soil microbial DNA was directly extracted from aeolian sandy soil. The DNA crude extracts were obtained by the cell lysis via the repeated freezing-thawing process of SDS, lysozyme, CTAB, proteinase K and liquid nitrogen in combination with the crude extracts purified by PEG (polyethylene glycol). In this way the large fragment DNA was obtained from the lytic cells with the DNA yield increased, i.e., 0.586~1.311 μg · g-1(dry soil). In addition, the fragment size of DNA was over 23 Kb, and PEG was helpful to remove humic acid in DNA effectively. The unpurified DNA could be directly used as templates for PCR amplification of 16S rDNA. The method mentioned above was simple and appropriate for DNA extraction from the aeolian sandy soil.
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    IGT-based dynamics analysis/forecast of environmental load in China
    Gao, Cheng-Kang (1); Jiao, Wen-Bin (2); Cai, Jiu-Ju (1); Zhu, Wei-Guang (1)
    2010, 31 (11):  1644-1647.  DOI: -
    Abstract ( 235 )   HTML   PDF (1622KB) ( 498 )  
    IGT equation and the equations derived from it were applied to establishing the quantitative relationship between economic growth and environmental load so as to solve some existing problems found in China's development. According to the interaction between the environmental load descent rate t and g*(g*=g/(1+g) where g is the annually average growth rate of GDP), the effect of economic growth on environmental load, was analyzed taking energy consumption, SO2 emission and chemical oxygen demand (COD) as indices. Based on the STIRPAT model derived from IPAT, the economic development and relevant environmental load in the period 2010~2020 was forecast according to different parameters in four cases. The results revealed that China should formulate appropriate policies and take powerful measures to ensure the sustainable development specifically the regulation for the interaction between g and t.
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    An AE source location combination algorithm based on least square method
    Kang, Yu-Mei (1); Liu, Jian-Po (1); Li, Hai-Bin (2); Wei, Chen-Hui (1)
    2010, 31 (11):  1648-1651+1656.  DOI: -
    Abstract ( 538 )   HTML   PDF (1195KB) ( 721 )  
    The location of AE(acoustic emission) source is an important task of acoustic emission monitoring. The basic principle of time difference of arrival(TDOA) location and conventional relevant methods to locate the acoustic emission source are described. Since the choice of initial value affects convergence rate and location accuracy in the 3-D algorithm of AE source location, a new Geiger iterative combination algorithm taking fully the advantage of estimation of the least square method is proposed to optimize the location. Numerical simulation showed that the algorithm proposed can effectively solve the problem of initial value for iteration and ensure the algorithm convergence with convergence rate improved.
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    Identification of consensus in group decision-making with multi-granularity linguistic information and compromise for discrepancy
    Jiang, Yan-Ping (1); Liang, Hai-Ming (1)
    2010, 31 (11):  1652-1656.  DOI: -
    Abstract ( 279 )   HTML   PDF (1545KB) ( 464 )  
    A method is proposed to analyze the consensus in group decision-making, based on the multi-granularity linguistic preference in terms of identifying information matrix. According to the different multi-granularity linguistic identifying information matrices given by experts, the relational vector for ranking individual schemes is determined by LOWA aggregation operators. Then, an objective programming model is developed to minimize the discrepancy between the opinions of group and experts, and the relational vector for ranking group schemes is obtained by solving the model. Defining the closeness index between the opinions of experts or individuals and of a group, a method to identify and improve their consensus is proposed. An example is given to show the feasibility and effectiveness of the methods proposed.
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    A cluster analysis based on combinational similarity for hybrid multi-index information
    Ren, Xiao-Yu (1); Yang, Xi-Huai (1); Zou, Jia-Xing (1); Guan, Ni-Yan (1)
    2010, 31 (11):  1657-1660.  DOI: -
    Abstract ( 395 )   HTML   PDF (1507KB) ( 488 )  
    Conventionally, a cluster is depicted with the measure of a single similarity among the objects in cluster analysis. The idea of combinational similarity is therefore proposed to get rid of the shortcoming. Because of the complexity, fuzziness and uncertainty of actual clustering problems, the clustering information is often a hybrid multi-index on which involves various forms of number, sucha as the precise real number, interval number and fuzzy number. A cluster analysis was made for the hybrid multi-index information via the idea of combinational similarity, and the results showed that the cluster analysis via the combinational similarity is more comprehensive than conventional ones because the hybrid index information is involved in analysis. A numerical example was given to illustrate the effectiveness of the proposed method.
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    A method for selecting partners of knowledge collaboration team based on concordant matrix
    Kang, Feng (1); Fan, Zhi-Ping (1); Zhang, Chong-Yang (1)
    2010, 31 (11):  1661-1664+1668.  DOI: -
    Abstract ( 212 )   HTML   PDF (1388KB) ( 525 )  
    To solve the problem that the team partners are selected improperly by multi-index decision-making or optimal modeling, a method based on harmony matrix is presented to select partners of a KC(knowledge collaboration) team. Describing the concept of KC and defining the KC team, an index system is set up for partner selection according to the characteristics of KC teams. Then, both the concordant and disconcordant matrices are built via the computation of concordant and disconcordant coefficients so as to determine the key kernel to pick up the preferable partner(s). The results of a numerical example revealed that the method proposed is able to deal with the concordant relation between all members of a KC team.
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    Assessing the integrated risk based on Choquet integral
    Zhang, Lei (1); Fan, Zhi-Ping (1); Yue, Qi (1)
    2010, 31 (11):  1665-1668.  DOI: -
    Abstract ( 624 )   HTML   PDF (1508KB) ( 607 )  
    To assess the integrated risk arising from the correlation between several risks, a risk assessment method based on Choquet integral was proposed. With the related concept and formula of Choquet integral introduced, the assessment of integrated risk involving correlated risks was described. Further, the formula of integrated risk assessment based on Choquet integral is expressed, with the feasibility and practicability of the proposed method exemplified.
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    Double-scale analysis of thermal elastic-viscoplasticity of BGA packaging
    Li, Ying-Mei (1); Liu, Jun (1); Liu, Jun (1)
    2010, 31 (11):  1669-1672.  DOI: -
    Abstract ( 261 )   HTML   PDF (1790KB) ( 539 )  
    The BGA packaging of flip-chip assembly with underfill was simplified into a multilayer board with imperfect periodical microstructure. Based on the homogenization theory with the Anand's unified viscoplastic constitutive model applied to the solder, a double-scale method was proposed to analyze the thermal elastic-viscoplasticity of this improper periodical microstructure. Then, the high-order discrete model was introduced layer by layer via the Rayleigh-Ritz method to analytically solve the problem of BGA under thermal cyclic loads microscopically and mesoscopically, thus determining the thermal stress and strain. The analytic method was verified simple and effective in comparison with FEM results. The result of a numerical example showed that the thermal load and thickness of glue underfill are the main influencing factors on the responses of thermal elastic-viscoplasticity of BGA in soldering.
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