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15 June 2009, Volume 30 Issue 6 Previous Issue    Next Issue
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Nosiheptide fermentation process modeling based on Elman neural network ensemble Niu, Da-Peng (1); Wang, Fu-Li (1); He, Da-Kuo (2); Jia, Ming-Xing (2) 2009, 30 (6):  761-764.  DOI: - Abstract ( 251 )   HTML   PDF (280KB) ( 740 )   In order to improve the poor extrapolation effect and generalizability of the single neural network, the neural network ensemble is used to develop the model of Nosiheptide fermentation process. Each individual network is trained on a bootstrap re-sampling replication of the original training data through the Bagging approach. Then, outputs of the individual neural networks are combined to form an overall output of neural network ensemble through the weighted average method, in which the weight of each individual network is determined by the differential evolution algorithm. The Elman network, a typical dynamic neural network, is applied in each individual network. The model of Nosiheptide fermentation product concentration, based on the neural network ensemble, is thus developed through combination of outputs from multi-Elman neural networks. This model is compared with the single neural network model to illustrate its high accuracy and generalizability. References | Related Articles | Metrics

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C-V model adaptive to complex background Cui, Hua (1); Gao, Li-Qun (1) 2009, 30 (6):  765-768.  DOI: - Abstract ( 218 )   HTML   PDF (482KB) ( 574 )   The segmentation by C-V models can achieve good effect only if there are two smoothly partitioned zones in an image, i.e. the object zone and background zone. However, when extracting image boundary from complex background, C-V model often cannot get correct results. To solve the problem, the conventional C-V model and mean shift are used to develop a C-V model to adapt to the complex background. This model can determine piecewise the interior and exterior zones of contour curves. Experimental results showed that the model developed is more adaptive to complex background in comparison with the conventional C-V model and can extract smoothly uninterrupted image boundaries from complex background. References | Related Articles | Metrics

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Dynamic real time adaption detection algorithm for moving vehicles in complex scenes Wu, Cheng-Dong (1); Liu, Meng (1); Zhang, Yun-Zhou (1); Chu, Hao (1) 2009, 30 (6):  769-772.  DOI: - Abstract ( 313 )   HTML   PDF (1004KB) ( 622 )   An algorithm based on adaptive background and improved dynamical threshold is proposed to solve the problem of the limitation of current detection methods of moving vehicle in complex scenes. Obtaining the difference image by the substraction between present frame and background, the precision detection of moving objects is implemented through binaryzing the three different color channels of the difference image by selecting adaptive threshold values. According to the detected objects, an updating strategy by mean values is introduced to achieve real-time update of background. Experimental results of outdoor image sequences demonstrated that the proposed algorithm can effectively detect moving objects in complex traffic scenes, and what's more its computation cost is reduced with higher robustness and real-time performance provided, thus meeting the requirements of real-time detection of moving vehicles in intelligent transportation surveillance system. References | Related Articles | Metrics

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A miniature fish-like robot with infrared remote receiver and IPMC actuator Hao, Li-Na (1); Xu, Su (1); Liu, Bin (1) 2009, 30 (6):  773-776.  DOI: - Abstract ( 274 )   HTML   PDF (516KB) ( 1071 )   As a new intelligent material, IPMC can be driven under low voltage with quick response to its deformation. With IPMC used as an actuator, a miniature fish-like robot was designed, which can be controlled by an infrared remote controller. The running direction and speed of the robot can be changed by readjusting the driving voltage amplitude/frequency to the IPMC. The different running speeds of the robot excited by sinusoidal wave and square wave were compared experimentally with each other, with the impact of the driving signal amplitude/frequency on the running speed verified. Experimental results showed that taking IPMC as actuator is available. References | Related Articles | Metrics

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Pricing business process reengineering and optimization based on process algebra in electronic commerce Guo, Zhe (1); Wu, Jun-Xin (1); Tang, Jia-Fu (1); Wang, Ding-Wei (1) 2009, 30 (6):  777-781.  DOI: - Abstract ( 296 )   HTML   PDF (1134KB) ( 593 )   Considering the unreasonable factors in conventional pricing business process, such as low level of information rate and automation and poor network, each and every step in the whole process of conventional pricing business was analyzed quantitatively by a method based on process algebra. Then the conventional process was reengineered in combination with the characteristics of pricing business process in electronic commerce circumstances, and the results of the two different processes were evaluated comparatively. Evaluation results showed that the pricing business process after reengineering can reduce the workload and mistakes, and quicken its response to relevant enterprises in electronic commerce. References | Related Articles | Metrics

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Evaluation and analysis of non-tariff barrier that China is faced with Jiang, Jian-Ye (1); Wang, Ding-Wei (1) 2009, 30 (6):  782-785.  DOI: - Abstract ( 435 )   HTML   PDF (204KB) ( 1211 )   The non-tariff barrier (NTB) is an important problem faced to China's exportation. Some western developed countries set different non-tariff barriers selectively to Chinese exports for their own economic benefits. Based on the concept of barrier coefficient, a quantified NTB evaluation method is proposed comprehensively for different exports from China, involving the technical barriers of trade (TBT) and the sanitary and phytosanitary (SPS) measures-both are the bases on which NTB takes effects. This method is used to evaluate and analyze the NTB the west selectively imposed on Chinese exports. Based on the quantified analysis results, several trade strategies are suggested to rise above such trade barriers. These suggestions have been provided to several export-oriented enterprises for the design of their export strategies. References | Related Articles | Metrics

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Quality control of key stages during cold roller machining procedure Wang, Li-Yan (1); Tang, Jia-Fu (1); Gong, Jun (1) 2009, 30 (6):  786-789.  DOI: - Abstract ( 251 )   HTML   PDF (232KB) ( 680 )   Machining the cold roller blank is typically a multistage and multivariable quality control process, of which the quality of some key stages requires highly strict control. Taking the cold roller blanks supplied from a certain steel plant as example, the main stages of their machining procedure are described and analyzed showing the necessity of quality control of key stages which are determined by the simply improved Taguchi's quality loss function. Moreover, the MPCI is analyzed and computed, and the rationality and effectiveness of this method is verified through exemplification. References | Related Articles | Metrics

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Speech visualization simulation based on LLE and fuzzy kernel clustering algorithm Han, Zhi-Yan (1); Wang, Xu (1); Wang, Jian (1); Xue, Li-Fang (1) 2009, 30 (6):  790-793.  DOI: - Abstract ( 274 )   HTML   PDF (1149KB) ( 536 )   According to the time-varying speech signal, a novel method combining LLE (locally linear embedding) with fuzzy kernel clustering algorithm was proposed for speech visualization, where LLE could reduce the nonlinear dimensionality of the speech features and then the fuzzy kernel clustering algorithm was used for clustering analysis, i.e. the Mercer kernel function was used to change the data in original space into a high-dimensional eigenspace through nonlinear mapping, and then the fuzzy clustering analysis was made in the high-dimensional eigenspace. Thus, after the kernel function mapping, the original inherent features of speech were highlighted to improve the position-based speech visualization. 720 data in Chinese vowels were obtained from 10 male and 10 female students' speech in lab, the results of simulation experiments show the feasibility and validity of the method. References | Related Articles | Metrics

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Semantic annotation based on CPN network for Deep Web data Ma, An-Xiang (1); Gao, Ke-Ning (1); Zhang, Xiao-Hong (1); Zhang, Bin (1) 2009, 30 (6):  794-797.  DOI: - Abstract ( 279 )   HTML   PDF (314KB) ( 998 )   An overall and accurate annotation of Deep Web data is the key to Deep Web data integration system. However, the existing methods of semantic annotation are unavailable to solve the problem well. An approach to semantic annotation based on CPN network is proposed for Deep Web data. By extracting the basic features of attribute values, semantic annotation is implemented with CPN network. At the same time, an effective method is proposed to obtain the attribute values on Deep Web result pages, thus laying a sound foundation for semantic annotation. Experimental results showed that the approach to semantic annotation based on CPN network improves the accuracy and recall. References | Related Articles | Metrics

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Fingerprint core point localization and its orientation computation Mao, Ke-Ming (1); Wang, Guo-Ren (1); Yu, Chang-Yong (1); Jin, Yan (1) 2009, 30 (6):  798-801.  DOI: - Abstract ( 378 )   HTML   PDF (1203KB) ( 715 )   Core point, as an essential feature of fingerprint, plays an important role in fingerprint matching/classification, where the core point region is distinguished from non-core point region by the machine learning method, and their ridge orientation distributions can be used to form training data. Then, the multi-resolution SVM method is used to gain a training model so as to predict accurately the position of core point by corresponding models. Moreover, the orientation of core point is defined reasonably and a heuristic method is devised to compute it. Experimental results showed that the proposed method can localize the position of core point and compute its orientation with high accuracy and efficiency. References | Related Articles | Metrics

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A QoS dynamic traffic grooming scheme Wang, Xing-Wei (1); Tong, Cheng-Cheng (1); Huang, Min (1) 2009, 30 (6):  802-804.  DOI: - Abstract ( 239 )   HTML   PDF (158KB) ( 608 )   With the constraints on both QoS (Quality of Service) and network resource considered for the traffic requested from users, a QoS dynamic traffic grooming scheme is proposed on optical Internet. It is based on a hierarchical graph model and the Dijkstra kth shortest path algorithm to minimize the network cost. With the concept of appetency introduced, the scheme tries to groom the newly arrived traffic requests and lead them to the existing lightpaths available to meet the requirements of bandwidth and delay as possible. Simulation results showed that the scheme proposed is feasible, practical and effective, since it not only support QoS but also improve the lightpath efficiency. References | Related Articles | Metrics

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PPLR-based load balancing scheme over multipath network Cai, Ling (1); Wang, Jin-Kuan (1); Wang, Cui-Rong (1) 2009, 30 (6):  805-808.  DOI: - Abstract ( 291 )   HTML   PDF (395KB) ( 1242 )   The conventional load balancing scheme for multipath network is impossible to provide in advance the predicted information before changing the state of the network. To solve the problem, a new load balancing scheme is proposed on PPLR (predictive path loss rate). Taking the packet loss rate of each and every path as observing value through relevant measurement, the time-fixed sequential prediction is introduced into the scheme to distribute load in accordance to PPLR. In addition, the packet loss rate is used as the penalty function of the distribution ratio of traffic flow through every path when readjusting load balancing, thus leading the flow to the paths at low packet loss rats. Results of analysis and simulation verified that the scheme proposed can balance load effectively and reduce the multipath packet loss rate. References | Related Articles | Metrics

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Design and implementation of a wireless sensor network node Zhao, Hai (1); Zhao, Jie (1); Liu, Zheng (1); Ji, Shu-Jie (1) 2009, 30 (6):  809-812.  DOI: - Abstract ( 305 )   HTML   PDF (330KB) ( 1250 )   The needs of a wireless sensor network node are analyzed with the architecture of the node described. According to the protocol 802.15.4, the design mode of the node consisting of the main controller ATmega128L and CC2420 RF transmission is adopted in modular form including the wireless communication, processor, sensor and power supply modules, thus implementing the design as a whole. Comparing the test results of data packets sending/receiving rates varying with the distance from the nodes thus designed with those from Micaz nodes and temperature data acquired by temperature sensor, the designed node shows a favorable effect and provides further a high performance hardware platform for in-depth study of wireless sensor networks. References | Related Articles | Metrics

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Preemption control strategy and optimization in embedded real-time system Liu, Zheng (1); Zhao, Hai (1); Li, Qiang (2); Zhang, Qian (2) 2009, 30 (6):  813-816.  DOI: - Abstract ( 270 )   HTML   PDF (306KB) ( 637 )   Preemption of tasks guarantees the schedulability of system but, on the other hand, the overheads relevant to preemption ate unavoidable. For the embedded real-time systems of which the resource is constrained, it is important to control the frequency of task preemption so as to reduce the resource consumption due to preemption. A preemption control model based on time slice is therefore proposed to assign every task on upper limit of preemptable frequency. To minimize the upper limit under the constraint on schedulability, the genetic algorithm is used to optimize it. Then, the algorithm for optimization is analyzed by simulation, and the result shows that the preemption control strategy proposed can reduce the frequency of preemption effectively during task execution. References | Related Articles | Metrics

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Cipher key management based on neural networks and facial biometrics feature Zhang, Xiang-De (1); Tang, Qing-Song (1); Lu, Xiao-Jun (1); Zhu, He-Gui (1) 2009, 30 (6):  817-820.  DOI: - Abstract ( 292 )   HTML   PDF (284KB) ( 619 )   A convenient and secure management scheme of cipher key is proposed taking advantage of the associative memory function from neural networks and embedding the cipher key in the user's facial biometrics feature. Extracting the user's facial biometrics feature and discretizing it to be a binary sequence through the principal component analysis (PCA), and the key is integrated into the facial biometrics sequence via XOR (exclusive-OR), and the XOR result and some random sequences are used to train the generalized regression neural networks. Eventually, what a user has to do is just storing the trained parameters of neural networks, XOR result of the key and facial biometrics sequence without the key to be stored or memorized. Then, only if a user inputs his own face image the key can be restored from the stored data whenever the key is required. An attacker is impossible to get the key or the information on user's facial biometrics feature, even if he has obtained the stored data. The experiment results showed that the proposed scheme is feasible. References | Related Articles | Metrics

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Microstructure and mechanical properties of a kind of Nb-V micro-alloyed forging steel Zhao, Yang (1); Chen, Li-Qing (1); Xu, Xiang-Qiu (2); Liu, Xiang-Hua (1) 2009, 30 (6):  821-824.  DOI: - Abstract ( 255 )   HTML   PDF (1202KB) ( 643 )   By means of optical microscopy, TEM and testing of mechanical properties, the microstructure and mechanical properties of a kind of Nb-V micro-alloyed forging steel was investigated. The results showed that it is a 0.24%C-1.99%Mn-0.30%Si-0.51%Cr-0.08%V-0.07%Nb steel that doesn't belong to tempered-hardened steel and has a better comprehensive performance after forging at 1200°C for 1hr with then air-or wind-cooled. The reason why it is improved is that the Nb-V micro-alloying process can effectively refine the microstructure of the steel, thus improving its impact toughness. The further analysis showed that this steel can be used to meet the demands for designing and manufacturing the front axle of heavy-duty trucks. References | Related Articles | Metrics

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On the cold rolling of twin-roll casting magnesium alloy strip Wang, Guang-Shan (1); Di, Hong-Shuang (1); Huang, Feng (1) 2009, 30 (6):  825-828.  DOI: - Abstract ( 354 )   HTML   PDF (1320KB) ( 602 )   An experiment was carried out in lab on vertical twin-roll casting machine with magnesium alloy AZ31 ingots as workpiece which were cold rolled to form strip then annealed directly. The parameters in the processes of vertical twin-roll cast-rolling and annealing, and the microstructure evolution of the finished cold strip were investigated. The results showed that the magnesium alloy strip is obtained successfully due to reasonable process parameters, especially in the twin-roll cast-rolling process both the quick chilling and pressured solidification improve the solidified structure of the strip of which the maximum deformation can be up to 40.7% if the magnesium alloy billet is cold-rolled directly. For the cold-rolled Mg alloy plate after annealing at 350°C for 30-60 min, the equiaxed fine grain structure with average grain size 9-10μm is available. References | Related Articles | Metrics

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Technological process and mechanical properties of low-cost X80 pipeline steel Xiao, Bao-Liang (1); Xu, Yun-Bo (1); Wang, Guo-Dong (1) 2009, 30 (6):  829-832.  DOI: - Abstract ( 538 )   HTML   PDF (549KB) ( 984 )   The pipeline steel was updated from X70 to X80 through TMCP technique, and its mechanical properties and fracture separation of rolled plate were studied. The results showed that both the longitudinal and transverse tensile strengths of strip specimen are better than those of round bar specimen, and the yield strength of round bar specimen increases first then decreases with increasing coiling temperature. All the values of the work done by impact AkV at -20°C are above 310 J, and all DBTTs are below -100°C. With a series of impact load-displacement curves analyzed, the work done by impact decreases and peak load increases with decreasing testing temperature. Furthermore, as shown by energy spectrometric analysis of impact fracture, the second-phase particles in the vicinity of the fracture surface are mainly of alumina and manganese sulfide. References | Related Articles | Metrics

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Mathematical model to schedule dieless drawing speed for tapered tubes Xia, Hong-Yan (1); Wu, Di (1); Luan, Gui-Fu (1) 2009, 30 (6):  833-836.  DOI: - Abstract ( 424 )   HTML   PDF (477KB) ( 725 )   Dieless drawing, as a flexible metal forming technique, could provide rods/tubes with varied cross-section in axial direction and some other formed materials which are hard to be deformed by conventional drawing process. Based on the analysis of deformation mechanism and feasibility of tapered tubes via dieless drawing process, the calculation method of dieless drawing speed and hot/cooling source moving speed during tube forming is proposed theoretically with a relevant mathematical model given. Experimental investigation results showed that the mathematical model indicates variation of dieless drawing speed and hot/cooling source moving speed quite well, and it is available to schedule the two different speeds for dieless drawing. References | Related Articles | Metrics

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Study on reducing loss of Fe-Si-Al soft magnetic powder cores Li, Qing-Da (1); Lian, Fa-Zeng (1); You, Jun-Hua (1); Chen, Yu-Lan (2) 2009, 30 (6):  837-840.  DOI: - Abstract ( 697 )   HTML   PDF (626KB) ( 1433 )   To prepare the high-performance Fe-Si-Al soft magnetic powder cores, how to reduce the loss of Fe-Si-Al magnetic powder cores was explored. SEM, metallographic microscope and B-H analyzer were used to characterize the interior structure, morphology and magnetic properties of samples. The results indicated that the annealing following compaction is crucial to reducing the loss of Fe-Si-Al powder cores, and increasing annealing temperature can effectively reduce both hysteresis loss and eddy current loss, but over-annealing temperature can increase eddy current loss. The range of optimal annealing temperature is 660-720°C. Although adding insulating material into the powder can effectively reduce eddy current loss by increasing the resistance of powder core, it has small influence on hysteresis loss. Increasing shaping pressure can reduce the loss of the magnetic powder cores and coercive force, and the optimal shaping pressure is 1800 MPa. References | Related Articles | Metrics

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Some influencing factors on preparation process of epoxy acrylate oligomer Gao, Peng (1); Xue, Xiang-Xin (1) 2009, 30 (6):  841-844.  DOI: - Abstract ( 499 )   HTML   PDF (224KB) ( 1453 )   The epoxy acrylate was synthesized with different amounts of inhibitor, feed ratios and feeding modes. The UV-curing coating was prepared, with the gel content in cured film measured. The results indicated that the esterification is improved with increasing content of inhibitor, but when the amount of inhibitor is up to 1.0%, the gel content of cured film decreases with esterification weakened. Slightly excessive content of epoxy in reactant is beneficial to improving the esterification. When the feed ratio n (Er):n (AA) is 1:2.0, the gel content in cured film comes up to maximum. The feeding mode that the acrylic acid, catalyst and inhibitor are premixed together and then added into epoxy is advantageous to improving the esterification of the synthesized product. References | Related Articles | Metrics

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Analysis of social stocks of metallic substance Yue, Qiang (1); Lu, Zhong-Wu (1) 2009, 30 (6):  845-848+852.  DOI: - Abstract ( 449 )   HTML   PDF (366KB) ( 681 )   Social stocks of metallic substance determine the secondary or recoverable resources to a certain extent. Two methods are given for the social stocks to analyze theoretically the variation of social stocks of metallic substance with the assumption that the metal consumption presents linear or quadratic curves. Exemplifying the copper industry in China, the variations of social stocks of copper and its consumption in the period from 1950 to 2007 were analyzed and the results reveal that the social stocks have come into a quicker growth period since year 2000. Proposes the notion of average age of social stocks of metals and its calculating formula, and an analysis is made to the average age (aa) of copper products in social stocks in the period. It is found that aa of copper products in the period decreased gradually since 1988 and basically remained unchanged from 2005 to 2007, i.e. about 7.8 years. References | Related Articles | Metrics

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Fiber bridging analysis of interlaminar short fibers in mode II delamination Liu, Jun (1); Li, Ying-Mei (1); Zhang, Feng-Peng (1) 2009, 30 (6):  849-852.  DOI: - Abstract ( 365 )   HTML   PDF (321KB) ( 672 )   To analyze the toughening mechanism of continuous fiber-reinforced resin composite laminates with interlaminar short fibers, the fact that the short fibers are distributed disorderly on interlayers and almost parallel to interlaminar cracks should be taken into consideration. Based on the coupling of matrix spalling and short fibers, the pull-out with the disturbance to unbridged short fibers during spalling considered, a bridging model is developed for interlaminar short fibers in mode II delamination to analyze the pull-out process of bridged fibers at different angles, the relationship between bridging force and crack-open displacement is obtained. The numerical results indicate that the displacement is very small except the angle is close to 90° and the bridging force increases rapidly before pull-out but decreases with greatly increasing displacement, i.e. the energy dissipation occurs mainly due to fibers' pull-out, and the bridging force and energy dissipation decrease with increasing pull-out angle. References | Related Articles | Metrics

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In-phase self-synchronous process of self-synchronous vibrating system with vibrators deviating from its center of mass Zhang, Nan (1); Hou, Xiao-Lin (2); Wen, Bang-Chun (1) 2009, 30 (6):  853-856.  DOI: - Abstract ( 410 )   HTML   PDF (581KB) ( 684 )   Self-synchronization and synchronic-drive vibration have been successfully applied in many engineering fields. An in-phase self-synchronous vibrating system with vibrators deviating from its center of mass is put forward. Based on Lagrange principle, a dynamic model is derived to give its electromechanical-coupling model and, based on the mathematical model, a simulation model is developed. The simulation results showed visually the processes in which the vibratory machines implement fully the transition from asynchronous to synchronous state or from one type of synchronous state to other type, which the conventional mechanic models are unavailable to explain quantitatively. Thus, the characteristics of self-synchronous vibration of vibrating system with vibrators deviating from its center of mass are revealed to provide a theoretical basis for designing similar products. References | Related Articles | Metrics

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Study and application of 11-DOF nonlinear ride comfort model for vehicle Li, Chao-Feng (1); Wang, De-Gang (1); Liu, Jie (2); Wen, Bang-Chun (1) 2009, 30 (6):  857-860.  DOI: - Abstract ( 445 )   HTML   PDF (481KB) ( 1072 )   Based on the conventional ride comfort model, an 11-DOF analysis model was developed with both the increasing of seats and the nonlinear factors of suspension damper taken into account. Considering the pitch-up/down and roll of the vehicle body, and the impact of seats on vehicle's ride comfort, the developed model involved more details. The vehicle body's vibration due to its vertical motion, pitch and roll and the four seats' vibration acceleration were obtained by the variable step integration. And the effects of different road surfaces, travelling speeds and sitting seats on vehicle's ride comfort were analyzed. The results showed that the 11-DOF analysis model developed for vehicle's ride comfort is more practical and accurate than evaluating just in accordance to vehicles body balancing. References | Related Articles | Metrics

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Transient transfer matrix method for thermal rub-impact faults in hot bending rotor system He, Wei (1); Yuan, Hui-Qun (2); Zhu, Xiang-Zhe (1) 2009, 30 (6):  861-864.  DOI: - Abstract ( 343 )   HTML   PDF (447KB) ( 722 )   In order to reveal the dynamical characteristics of transient thermal rub impact in a hot bending rotor system, the transient transfer matrix method was used to develop the dynamical equations of unsteady thermal rub impact through combining Riccati transfer matrix method with Wilson-θ method. The unsteady thermal rub impact was numerically computed and analyzed in the warm starting process of a multi-disk rotor, and the point rub impact and one-side wear-out faults of the hot bending rotor were simulated in steady-state temperature field. Some dynamical characteristics of unsteady thermal rub impact owing to the imbalance force and hot bending were therefore found. As a result, a theoretic and computational foundation is laid down for improving the stability of the rotor system to avoid or overcome such dangerous condition. References | Related Articles | Metrics

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Stiffness characteristics of 3-PRR planar parallel mechanism based on CCT stiffness matrix Li, Shu-Jun (1); Meng, Qiao-Ling (1) 2009, 30 (6):  865-868.  DOI: - Abstract ( 480 )   HTML   PDF (642KB) ( 785 )   To reveal the stiffness behavior of a parallel mechanism with considering the effect of the change in geometry due to compliance caused by the external forces, the stiffness characteristics of 3-PRR planar parallel mechanism were studied systemically. The analytical expressions of stiffness of the mechanism were derived on the basis of conservative congruence transformation (CCT) stiffness matrix. Then, the stiffness mapping curves of the 3-PRR mechanism were given to show the change and behavior of the stiffness with and without external forces acted on the mechanism, thus comparing the different changes in the stiffness and how it changes. And the stiffness characteristics of the mechanism were analyzed and discussed in details according to the stiffness expressions and numerical examples. The results show that the stiffness of the 3-PRR mechanism is configuration dependent, and proportional to the actuating forces and joint stiffness. The stiffness correlates not only to the magnitude of external forces but also the direction in which the external force act upon. References | Related Articles | Metrics

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Research on the XML application of networked manufacturing Wang, Jun (1); Sun, Jun (2); Wang, Wan-Shan (1) 2009, 30 (6):  869-872+876.  DOI: - Abstract ( 448 )   HTML   PDF (508KB) ( 583 )   The architecture of a networked machining system was framed according to the requirements of CNC system for networked manufacture. And the configuration language was used to set up the XML Schema mapping criterion database so as to implement the conversion of the STEP-NC programs for the information release of products with XML files, thus solving the problem of data exchange/sharing among the corporations in a network. The functional architecture of XML interpreter was designed to read relevant files so as to analyze the information such as geometric parameters, coordinates and tools, and they were all picked out and stored to provide recognizable data source for the core of the DSP controller. The program conversion and interpretation of XML files provided by the STEP-NC networked machining system are good in modularization with simple architecture, powerful function and high efficiency and, as a result, beneficial to system information integration. References | Related Articles | Metrics

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Characteristics of the TiOx films deposited by E-beam evaporation for cardiovascular applications: Hydrophilicity and hematypic compatibility Lin, Zeng (1); Lü, Shao-Bo (1); Lin, Tie-Yuan (1); Ba, De-Chun (1) 2009, 30 (6):  873-876.  DOI: - Abstract ( 353 )   HTML   PDF (932KB) ( 647 )   TiOx thin films were deposited on commercial Ti discs by E-beam evaporation and they were tested for their applications to cardiovascular stents. A goniometer was used to measure the contact angle of a drop of water falling onto the prepared thin film. It was found that the angle decreases with the increasing O2 flow rate in film depositing process and, after heat-treatment, the hydrophilicity of film is improved. Investigates the relationship between film structure and cellular activity via observing the growth behavior of PASMC (porcine aortic smooth muscle cells) on film samples. The results revealed that the Ti discs coated with the TiOx films have higher biocompatibility which can be improved further by the heat-treatment after film deposition. The hematypic compatibility of the films was studied via observing the adsorption behavior of platelets and it is found only few platelets are adsorbed onto the films. In conclusion, the TiOx thin films deposited by E-beam can be applied to the surface modification of cardiovascular stents. References | Related Articles | Metrics

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3-D model for key block due to rock tunnel construction and its computerized verification Wang, Shu-Hong (1); Yang, Yong (1); Guo, Mu-Dan (1); Wang, Yang (1) 2009, 30 (6):  877-880+912.  DOI: - Abstract ( 440 )   HTML   PDF (1139KB) ( 633 )   With the field survey done for structural planes in rock mass as the geological conditions for tunnel engineering, the 3-D model of structural planes and relevant network simulation were investigated. The two searching techniques for key blocks were discussed via simulating the geometric features of real rock mass in according to the network graph of discontinuous structural planes, i.e. the methods to search randomly the blocks in accordance to either the structural plane parameters determined or the network graph of jointer planes. Then, introducing the probability theory to analyze the key blocks in rock mass dissected by joints and the Monte Carlo method with object-oriented programming, a 3-D simulation modeling technique was given by computer on the basis of statistical for discontinuous planes in rock mass theory. Thus, a block searching computing model adaptable to engineering was set up to implement the computer searching for key blocks with 3-D display and image rotation. References | Related Articles | Metrics

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Decolorization of simulated printing and dyeing effluents with CWAO technology Zhang, Yong-Li (1); Li, Liang (1); Hu, Xiao-Min (1) 2009, 30 (6):  881-884.  DOI: - Abstract ( 390 )   HTML   PDF (144KB) ( 812 )   In order to study on the effect of simulated printing and dyeing effluents decolorization with catalytic wet air oxidation (CWAO) technology, methylene blue aqueous solution with chroma of 300000 was chosen as simulated printing and dyeing effluents, and Cu1Fe1 with m (Cu2+):m (Fe2+) = 1:1 was used as homogeneous catalyst, then the effect of sample decolorization was investigated on catalyst dosage, oxygen partial pressure, reaction temperature, pH of influent and the reaction time. The results show that the decolorization rates of sample increases with the increase in dosage of catalyst, oxygen partial pressure, reaction temperature and prolonged reaction time. However, there is an extreme point of pH value of influent, and the decolorization rates increases with the decrease in the pH value under acidic conditions, and with the increase in the pH value under alkaline conditions. At the optimized technics conditions, the decolorization rate of sample is up to 99.99% after such a reaction for 60 min. References | Related Articles | Metrics

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Research on environmental pressure of air pollutants emission in Shenyang Gu, Xiao-Wei (1); Wang, Zhong-Xin (1); Wang, Qing (1); Liu, Jian-Xing (1) 2009, 30 (6):  885-888.  DOI: - Abstract ( 421 )   HTML   PDF (1169KB) ( 857 )   Based on such indices as the annual mean values of pollutant concentration in atmosphere and the total emissivity of pollutants, the air quality in Shenyang was analyzed briefly with the comprehensive environmental pressure due to air pollutants quantified by ecological footprint. The results showed that the total amount of SO2 was reduced significantly during the past 10 years. However, the total amount of CO2 emission increased rapidly. Characterized by ecological footprints, the comprehensive environmental pressure due to air pollutants were mainly caused by CO2 and SO2. In the period from 1990 to 1994, the footprints of them were about half and half in total footprints. In the period from 1995 to 2000, the proportion of CO2 increased not greatly but, after the year 2000, it increased rapidly even up to 90% in 2005. The facts revealed that the environmental efficiency in economic development characterized by both air pollutant emission and ecological footprint, was improved obviously per unit GDP, and that the influence of the unit GDP offered by economic development on the air quality which is an integral part of ecological environment and its pressure had been weakened. References | Related Articles | Metrics

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Study on dimensionless methods in dynamic comprehensive evaluation Yi, Ping-Tao (1); Zhang, Dan-Ning (2); Guo, Ya-Jun (1); Gao, Li-Qun (3) 2009, 30 (6):  889-892.  DOI: - Abstract ( 493 )   HTML   PDF (244KB) ( 1644 )   There is a problem that the implicit increment information in data can be eliminated when processing the data of time series in existing dynamic comprehensive evaluation by static dimensionless methods. To solve the problem, three improved methods are suggested, i.e. the standard-series, whole-series and increment-weight methods, with a numerical example given to analyze their characteristics. The results showed that if there is no special subjective preference between transverse and lengthways information, the whole-series method is an explicit and easy one available to extend well to various static dimensionless methods and keep on the data characteristics of original method fully. It is therefore recommended to adopt the whole-series method prior to others. Moreover, the thoughts as above could be applied to dynamic non-linear dimensionless problems. References | Related Articles | Metrics

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A method of mass evaluation balancing discrepancy and consistency Zhang, Fa-Ming (1); Guo, Ya-Jun (1) 2009, 30 (6):  893-896.  DOI: - Abstract ( 380 )   HTML   PDF (1313KB) ( 820 )   For a mass evaluation which is carrying out with a large number of experts (stakeholders) participating in it, a method is proposed to balance the discrepancy and consistency in evaluation results, representing diverse alternatives to highlight the discrepancy as much as possible and reasoning out a conclusion in which the consistency will be acceptable to all participants. In this method the discrepancy between different alternatives is enabled to the utmost extent and all the alternatives are divided according to the stabilized discrepancy, thus ensuring the consistency of evaluation results that were given by different participants whose alternatives were of the same category. Then, the information between different categories are aggregated according to the generic influence so as to reach a conclusion of consistency acceptable to all participants. An application example is given to illustrate the validity of this method. References | Related Articles | Metrics

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An analysis frame about enterprise innovation strategy based on technological characteristics: Example from equipment manufacturing industries in Liaoning Province Zhao, Jian-Hua (1); Zhao, Xin-Liang (1) 2009, 30 (6):  897-900.  DOI: - Abstract ( 296 )   HTML   PDF (216KB) ( 519 )   The technological environment for industrial development includes two parts. One is the external environment which usually includes the variation rate of technology and heterogeneity of technological capabilities, and the other is the internal environment that is typically represented by technological capabilities. Based on the three factors explained as dimensionalities, a method is developed to evaluate the industrial technological characteristics and, according to them, different industries are clustered to frame and analyze the technology innovation strategy for enterprises. Thus, the theoretical basis and methodology of analysis are provided for enterprises to predict the technological development, analyze technological environment and selecting technological innovation strategy. An empirical analysis is made for 12 main industries in equipment manufacture in Liaoning Province. References | Related Articles | Metrics

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Portfolio compromise programming based on fuzzy time series Zhuang, Xin-Tian (1); Liu, Yang (1); Chi, Li-Xu (1) 2009, 30 (6):  901-904.  DOI: - Abstract ( 338 )   HTML   PDF (242KB) ( 521 )   A fuzzy time series is set up to forecast the securities price, which is a trapezoidal fuzzy number, and the forecasting of return on investment is measured in the ratio of forecasted value to purchasing price of securities. The model is solved by compromise programming based on the double-object model and compared with the effect of portfolio in terms of mean-absolute deviations. An empirical analysis is therefore made for 15 stocks picked out from SSE 50 indexing stocks. The results revealed that the compromise programming is available for decision-making of investment in accordance to the market quotation trend. The compromise programming also avoids the invalid solution to the problem that the double-objective model in terms of mean-absolute deviations under strict restriction on data. References | Related Articles | Metrics

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Modified SOR-like method for solution to saddle point problem Shen, Hai-Long (1); Shao, Xin-Hui (1); Zhang, Tie (1); Li, Chang-Jun (1) 2009, 30 (6):  905-908.  DOI: - Abstract ( 413 )   HTML   PDF (1711KB) ( 992 )   A new iterative solution with undetermined parameters is proposed to solve the problem of large-scale sparse saddle point, i.e. the modified SOR-like method or MPSOR-like method. Based on a splitting for the matrix of coefficients, the iteration method needs the choices of a pretreated matrix and undetermined parameters. After the choices were done, the iteration method proposed becomes convergent in form of theorem, thus giving a basic equality between the eigenvalue of iterative matrix and the parameters, with the sufficient and necessary conditions deduced for the convergence of the iteration method. The new method shows theoretically that it is more extensive with quicker convergence rate than the SOR-like method if the parameters is chosen properly. An experimental result of the iteration method is given numerically. References | Related Articles | Metrics

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Molecular dynamics study on structural change of a Cu59 cluster during heating Zhang, Lin (1); Sun, Hai-Xia (1) 2009, 30 (6):  909-912.  DOI: - Abstract ( 207 )   HTML   PDF (498KB) ( 520 )   The structural change in a Cu59 cluster from solid-state to melt during heating was investigated with the molecular dynamics simulations based on embedded-atom potential. Analyzing the local change in atomic structure in the 4 shells, which are determined by the atomic density distribution function with rising temperature, it was found that the Cu59 cluster structure changed in 3 stages due to the continuous interatomic position interchange during heating. First, a near-icosahedral structure takes place, which is composed of thirteen atoms and formed inside the cluster. Then, the atomic structure within every shell gradually changes disorderly. Finally, the molten-state Cu59 cluster is formed, of which the atoms are distributed within 3 shells. References | Related Articles | Metrics