Archive

15 December 2009, Volume 30 Issue 12 Previous Issue    Next Issue
---
OriginalPaper


For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

OriginalPaper

Select

CBR-based intelligently optimized index setting for clinker cooling process with grate cooler Qiao, Jing-Hui (1); Chai, Tian-You (1); Sun, Ming-Yan (3); Yue, Heng (1) 2009, 30 (12):  1673-1677.  DOI: - Abstract ( 280 )   HTML   PDF (1145KB) ( 902 )   In the cement production process it is hard to develop an accurate mathematical model for both f-CaO and stack bed thickness which characterize the key technical indices in the cooling process with a grate cooler. However, it is also hard to control efficiently the process by conventional methods. Combining the case-based reasoning (CBR) with conventional control method in clinker cooling process, a new control method is proposed to optimize intelligently the index setting by CBR, thus stabilizing the interval control of the mass fraction of f-CaO in clinker and stack bed thickness. The intelligently optimized index model can update automatically all basic loop setpoints so as to avoid the subjectivity and randomness due to the arbitrary manual setting. The approach proposed has been successfully applied to the clinker cooling process with grate cooler in a cement plant, and the application results showed its effectiveness. References | Related Articles | Metrics

Select

Research and application of unfalsified control Ren, Tao (1); Gao, Zhen-Hua (2); Zu, Guo-Qi (3); Luo, Xiao-Chuan (4) 2009, 30 (12):  1678-1681.  DOI: - Abstract ( 303 )   HTML   PDF (848KB) ( 1251 )   An unfalsified controller was designed for MIMO (multi-input multi-output) system and the conditions for BIBO(bounded-input bounded-output) stabilization of closed-loop systems where given via theoretical proof. The proposed method is data-driven and doesn't relay on system model. The controller designed is so simple that it is highly adaptable to application on line. The feasibility and effectiveness of this algorithm are confirmed by a simulation applying it to an inverted swinging pendulum system. References | Related Articles | Metrics

Select

Robust H∞ control of a class of T-S fuzzy bilinear interrelated large-scale systems Song, Rui-Zhuo (1); Luo, Yan-Hong (1); Liu, Zhao-Bing (1) 2009, 30 (12):  1682-1685.  DOI: - Abstract ( 246 )   HTML   PDF (406KB) ( 521 )   A robust fuzzy control of T-S fuzzy bilinear interrelated large-scale systems with exterior perturbation is presented. With the Takagi-Sugeno (T-S) fuzzy modeling technique used to develop a fuzzy bilinear model, both the direct Lyapunov method and parallel distributed compensation (PDC) method are employed to stabilize the fuzzy bilinear interrelated large-scale systems, then the sufficient condition is derived to satisfy the performance indices via linear matrix inequalities (LMI). Simulation results verified the feasiblity and effectiveness of the method proposed. References | Related Articles | Metrics

Select

A power controlled cross-layer communication protocol for wireless sensor network Ji, Peng (1); Wu, Cheng-Dong (1); Zhang, Yun-Zhou (1); Jia, Zi-Xi (1) 2009, 30 (12):  1686-1689.  DOI: - Abstract ( 245 )   HTML   PDF (540KB) ( 682 )   A novel cross-layer communication protocol is proposed and named power controlled directed spanning tree (PCDST), where a directed spanning tree routing algorithm is introduced to solve the problem of unnecessary energy consumption during data transmission and control the transmission power of node so as to moderate the competition intensity in communication network. A network utility maximum (NUM) model is developed to control further the transmission power that is regarded as a key factor. Based on the Prim-dual algorithm, a Lagrange dual function is designed to deduce the optimal solution set of transmission power. Taking advantage of such cross-layer strategies, WSN is enable to keep up smooth communication with energy saving. The simulation results showed that the performance of the proposed protocol is much better in both energy efficiency and improvement of communication throughput. References | Related Articles | Metrics

Select

Speech endpoint detection algorithm based on short-time energy-zero-product and discrimination information Han, Zhi-Yan (1); Wang, Xu (1); Wang, Jian (1) 2009, 30 (12):  1690-1693.  DOI: - Abstract ( 260 )   HTML   PDF (516KB) ( 600 )   To improve the accuracy of speech endpoint detection in low signal-to-noise ratio(SNR), a new algorithm was proposed. It combines the short-time energy-zero-product with discrimination information, denoising and endpoint detection simultaneously. Then, the frames judged as noisy ones are rechecked via the discrimination information based on the sub-band energy distribution probability to update the noise energy threshold, thus tracking the change for noise energy more accurate. Simulation results showed that the algorithm proposed is able to detect endpoints accurately even if the SNR changes acutely, and it will serve very well the function of subsequent processing of speech signal. References | Related Articles | Metrics

Select

The research of multi-dimensional scaling iterations localization algorithm based on rssi Bao, Xi-Rong (1); Zhang, Li-Li (1); Zhang, Shi (1) 2009, 30 (12):  1694-1697.  DOI: - Abstract ( 252 )   HTML   PDF (826KB) ( 913 )   Localization is an intrinsic issue in wireless sensor networks. To make up for the deficiencies of the classic multi-dimensional scaling algorithm MDS-MAP as to its localizing accuracy and complexity in matrix computation, the RSSI-GA algorithm was proposed. In its multi-dimensional scaling process a dissimilarity matrix is directly formed according to the value of wireless signal intensity. Analyzing the dissimilarity of individuals and geometric constraint relationship the distances between nodes, a mathematical model was developed with the positions of unknown nodes as parameters. Then, the genetic algorithm was introduced to solve the model so as to compute the node coordinates directly. Simulation results showed that the RSSI-GA algorithm can reduce greatly the cost for computation and improve the accuracy of localization efficiently. References | Related Articles | Metrics

Select

Optimization of topology of low-voltage network in solar photovoltaic stations Guan, Shou-Ping (1); Hao, Li-Ying (1) 2009, 30 (12):  1698-1701.  DOI: - Abstract ( 486 )   HTML   PDF (743KB) ( 881 )   To optimize the topology of low-voltage network so as to take advantage of electric power efficiently is of importance to the research on solar photovoltaic power systems. An approach is therefore presented that the power supply zone of a solar photovoltaic power station should be divided into several subzones by the K-means clustering algorithm, then the topology of network is optimized with the improved minimum spanning tree algorithm in every subzone. Simulation results showed that the line loss of low-voltage network decreases, which thus improved greatly the utilization of electric power. References | Related Articles | Metrics

Select

Mathematical model for minimum ignition energy of dust clouds Ren, Chun-Li (1); Li, Xin-Guang (1); Wang, Fu-Li (1); Radandt, S. (2) 2009, 30 (12):  1702-1705.  DOI: - Abstract ( 305 )   HTML   PDF (1331KB) ( 568 )   Using the equivalent data calculated for electric spark obtained from experiment as energy input and according to the ignition mechanism of dust clouds, a mathematical model was developed for the minimum ignition energy of dust clouds. Then, the influence of dust particle size, dust concentration, turbulence, spark energy density and spark discharging time on minimum ignition energy was studied through model calculation. The result was basically consistent with the experiment data, and combining the model calculation with experimental measurement could make the determination of minimum ignition energy of dust clouds more accurate and reasonable. References | Related Articles | Metrics

Select

A cardinality-tunable skyline query: Fuzzy skyline Zhao, Xiang-Guo (1); Huang, Jian-Mei (1); Wang, Guo-Ren (1); Xin, Jun-Chang (1) 2009, 30 (12):  1706-1709.  DOI: - Abstract ( 258 )   HTML   PDF (438KB) ( 522 )   To solve the problem that the number of the results of skyline query increases with the increasing dimensionality, a concept of fuzzy skyline set is defined on the basis of the theory of fuzzy sets to quantify the contribution of the different data points make to skyline query. Then, the number of the results of skyline query can be controlled accurately by taking different cutsets in the fuzzy skyline set. Meanwhile, the FACA algorithm is proposed to solve any of the fuzzy skylines so as to provide δ data points for customers, thus facilitating their decision-making. Testing results showed that fuzzy skyline query is a new useful cardinality-tunable skyline query, and FSCA is an effective way to solve fuzzy skyline. Both provide an ancillary means for customers to make decisions. References | Related Articles | Metrics

Select

Coreness analysis on large-scale software macro-topology Li, Hui (1); Zhao, Hai (1); Ai, Jun (1); Li, Bo (1) 2009, 30 (12):  1710-1713.  DOI: - Abstract ( 217 )   HTML   PDF (696KB) ( 809 )   For the macro-topology which shows hierarchical characteristics in large-scale software, coreness distribution and the correlation with degree, the effect of nodes with highest coreness on each and every layer and the trend of software structure coreness evolution analyzed on the basis of a large number of statistics data on coreness of open source software architecture. The result reveals that the k-coremax of software structure is generally small, the coreness distribution is scale-free characteristic, and the nodes with highest coreness have powerful influence. There is a certain positive correlation between coreness and degree for low-degree nodes, however, the coreness does not increase with the growing degree when the coreness comes up to a certain value, and the k-coremax and software core architecture remain stable during software evolution. References | Related Articles | Metrics

Select

Software-kernel of software network and S-model approximation during software growth Ai, Jun (1); Zhao, Hai (1); Li, Hui (1); Zhou, Feng (1) 2009, 30 (12):  1714-1717.  DOI: - Abstract ( 208 )   HTML   PDF (1405KB) ( 482 )   Because of the complexity in studies on software code and software network, the software-kernel of software network is defined and extracted to reduce the difficulty of grasping and measuring any software. Then a software-kernel layer stripping algorithm is developed to study the software-kernel with a certain amount of samples. The analysis results showed that the ordinal number of software-kernel layer of any software is directly proportional to the growth of that software, i.e. its upgrading evolution. The ratio of ordinal number of a kernel layer to the number of nodes of a software-kernel thus approximates to the S-model during the growth of software. Such a result is available to study the hierarchy of measuring softwares. Moreover, the extraction of software-kernel can be used to simplify the grasping of softwares and focus on the design, implementation and testing of key classes in softwares. References | Related Articles | Metrics

Select

Energy-balancing data collection based on the multiplicatively weighted voronoi diagram in sensor networks Yu, Rui-Yun (1); Wang, Xing-Wei (2); Yi, Xiu-Shuang (3) 2009, 30 (12):  1718-1722.  DOI: - Abstract ( 244 )   HTML   PDF (756KB) ( 498 )   Based on the multiplicatively weighted Voronoi diagram, an optimized path is designed to acquire data in sparse sensor networks. In the path, the data acquisition is implemented via the mobile acquiring nodes to visit a vertex subset of the virtual Voronoi diagram which is constructed through an iterative virtual site insertion process. The vertex subset covers all sensor nodes in a given transmission radius with the balanced energy consumption taken into consideration. The optimized path concatenating the vertex subset is much shorter than that generated by sensor nodes, thus reduces the time delay in data acquisition. A trade-off between time delay and energy consumption is implemented to meet different requirements by adjusting the coverage coefficient of virtual Voronoi diagram. References | Related Articles | Metrics

Select

Dynamic minimum interference routing algorithm based on profile in traffic engineering Du, Li (1); Guo, Kang (1); Yu, Jun-Xiang (1) 2009, 30 (12):  1723-1726+1750.  DOI: - Abstract ( 259 )   HTML   PDF (710KB) ( 903 )   A new minimum interference routing algorithm P-DMIR (profile-dynamic minimum interference routing) was proposed, which is divided into offline and online stages. In the offline stage the critical values of all links are determined with both the topology information and traffic profile introduced to make the algorithm available to process more information concretely without increased complexity. In the online stage the cost function coefficient of every link is calculated according to the types of the services on arrival, then the weights of links are calculated according to the reciprocal of available bandwidth and the critical value of every link so as to minimize the interference with the algorithm complexity reduced. Furthermore, the updating mechanism is provided regularly via the critical values of links, thus making the traffic profile instant and accurate. The simulation results showed that P-DMIR can allocate the different traffic flows to different paths rationally and avoid the network congestion effectively, and that it is superior to conventional algorithms in respect to the reject rate of requests and throughput of network. References | Related Articles | Metrics

Select

Investigation on the preparation of ionic polymer-metal composite (IPMC) Hao, Li-Na (1); Zhou, Yi-Ran (2) 2009, 30 (12):  1727-1730.  DOI: - Abstract ( 245 )   HTML   PDF (1159KB) ( 659 )   The preparation process of ionic polymer-metal composite(IPMC) as artificial muscle includes three steps: the pre-treatment, and the primary and secondary chemical plating reactions. Properties of the specimens to which the number of secondary chemical plating reactions were done differently after primary ones were in contrast with each other. With a signal generator designed to actuate IPMC, a test platform based on PC and data acquisition card was built to test the actuating characteristic of prepared specimens and the influence of frequency and amplitude of exciting signal and plating thickness on the characteristic so as to provide reference for the design and control of IPMC. Testing results showed that the lower the resistance of IPMC plating and the frequency of exciting signal, the higher the voltage of exciting signal, the bigger the fluctuation range. Increasing the plating thickness will facilitate the decrease in IPMC's resistance, but the plating cannot be too thick because of the increasing hardness. Burnishing the plating will result in inhomogeneous electrode surface, thus increasing the resistance of IPMC and decreasing its activity. References | Related Articles | Metrics

Select

Influence of deformation rate on strain-induced phase transition of 2205 duplex stainless steel Wang, Yue-Xiang (1); Liu, Zhen-Yu (1); Wang, Guo-Dong (1); Jiang, Lai-Zhu (2) 2009, 30 (12):  1731-1734.  DOI: - Abstract ( 240 )   HTML   PDF (1993KB) ( 747 )   The change of phase proportion of the austenite (γ) and ferrite (δ) in the microstructure of 2205 duplex stainless steel during thermal deformation was investigated by single-pass reduction simulation. The results showed that there are not only the phase transition between austenite and ferrite but also a dynamic softening mechanism due to the transition during thermal deformation of the stainless steel. The influence of deformation rate on phase transition during thermal deformation was found in such a way that the δ&rarrγ transition is dominant if the deformation rate is very small, but the portion of γ&rarrδ transition increases with increasing deformation rate. References | Related Articles | Metrics

Select

Effect of controlled rolling temperature interval on microstructure and mechanical properties of hot rolled Nb-contained multiphase steel Li, Yan-Mei (1); Zheng, Dong-Sheng (1); Zhu, Fu-Xian (1) 2009, 30 (12):  1735-1738.  DOI: - Abstract ( 240 )   HTML   PDF (1272KB) ( 479 )   The Nb-contained microalloyed experimental steel was investigated via thermomechanical controlled processing (TMCP) including two-stage rolling with laminar cooling, air cooling and ultra-fast cooling over three different finish rolling temperature intervals. After such a TMCP, the microstructures containing ferrite, bainite, martensite and a bit of retained austenite were obtained. Then the effect of controlled rolling temperature interval on the microstructure and mechanical properties of experimental steel was analyzed. The results show that when controlled cooling parameters are similar to each other, tensile strength decreases but yield strength, percentage elongation and product of tensile strength and ductility all increase with the decreasing starting and final temperatures of finish rolling. With the cooling conditions during TMCP mentioned above, when the temperature interval during finish rolling is 850~800°C, yield strength, percentage elongation and product of tensile strength and ductility all come up to their maximum values, i.e. 513 MPa, 35% and 25235 MPa·%, respectively. References | Related Articles | Metrics

Select

Influence of cooling rate on microstructure evolution due to deformation induced ferrite transformation in vanadium microalloyed steel Wang, Kai (1); Yu, Hai-Yan (2); He, Ji-Cheng (1); Liu, Chun-Ming (2) 2009, 30 (12):  1739-1742.  DOI: - Abstract ( 268 )   HTML   PDF (2691KB) ( 642 )   The effect of cooling rate on DIFT (deformation induced ferrite transformation) microstructure evolution during continuously cooling was investigated for the vanadium microalloyed steel via thermo-simulator. The simulation results showed that the higher the cooling rate after large deformation, the finer the DIF (deformation induced ferrite) grains in specimens and, at the same cooling rate, the higher the vanadium content in the steel, the finer the DIF grains. However, at lower cooling rate, the higher the vanadium content, the more the carbonitride precipitates from vanadium, and no carbonitride precipitates are found in specimens at higher cooling rate. References | Related Articles | Metrics

Select

Solid-phase reaction and microstructure of interface of 3D meshy SiCn/20Cr steel composite Ru, Hong-Qiang (1); Li, Jing-Yang (1); Qu, Xiang-Yu (1); Yu, Liang (1) 2009, 30 (12):  1743-1746.  DOI: - Abstract ( 407 )   HTML   PDF (1887KB) ( 769 )   The interface of the SiCn/20Cr steel composite material fabricated via vacuum-gas casting process was investigated with XRD and EDS (energy-dispersive spectroscopy analyzer) attached to SEM. The result revealed that an intensive solid-phase reaction occurs on the composite's interface between SiC and 20Cr steel, then SiC decomposed into Si that forms Fe-Si compound with Fe and C that precipitated in graphite form. The solid-phase reaction zone is composed of three zones, i.e. the metal, silicon carbide and carbon precipitation zones. The precipitating form of C in carbon precipitation zone relates to the distance between the precipitation position and silicon carbide. The (Cr, Fe)23C6 and Fe3Si is the products from metal reaction zone are verified by transmission electron microscope (TEM), of which the formation of Fe3Si provides thermodynamically the driving force for the decomposition of SiC. References | Related Articles | Metrics

Select

Correlation between thixoforming stress and deformation parameters of semi-solid alloy ZL201 Wang, Ping (1); Gao, Chao (2); Lu, Wen-Quan (1); Cui, Jian-Zhong (1) 2009, 30 (12):  1747-1750.  DOI: - Abstract ( 282 )   HTML   PDF (1016KB) ( 534 )   The compression deformation process of the semi-solid alloy ZL201 and the influence of its strain rate and deformation extent/temperature on the thixoforming stress were investigated on the Gleeble-1500 thermo-simulator. It was revealed that the higher the deformation temperature, the lower the thixoforming stress of specimens at the same strain rate. On the other hand, if the deformation temperature remains unchanged and the strain rate Ε˙<5 s-1, the higher the strain rates, the higher the thixoforming stress. And if Ε˙>5 s-1, the thixoforming stress tends to decrease with increasing strain rate. The results can provide the basic data for the optimization of process parameters of semi-solid metals. References | Related Articles | Metrics

Select

Calculation of transversal slab thickness during plate rolling He, Chun-Yu (1); Wu, Di (1); Zhao, Xian-Ming (1) 2009, 30 (12):  1751-1754.  DOI: - Abstract ( 322 )   HTML   PDF (893KB) ( 746 )   In the plate rolling process some asymmetrical rolling conditions may change the balance of roll system and affect the transversal thickness distribution of workpiece, thus resulting in abnormal crown distribution and the workpiece which deviates from normal rolling direction. Eventually, the plate shape will be poor with inaccurate size. Based on the assumptions of cantilever beam and semi-infinite elements with the work roll flattening taken into account, an influence function is derived to calculate the transversal thickness distribution of workpiece. By the calculation and analysis of rolls and workpiece, a quantified relation between the transversal thickness of workpiece and asymmetrical rolling conditions is obtained. Such a calculation of transversal thickness is of significance to avoiding side camber and improving the rate of finished products. References | Related Articles | Metrics

Select

Study on influencing factors on preparing process of borax from boron-rich slag Li, Jie (1); Fan, Zhan-Guo (1) 2009, 30 (12):  1755-1758.  DOI: - Abstract ( 317 )   HTML   PDF (694KB) ( 556 )   Boron-rich slag could be separated from ludwigite by pyrometallurgical method. Na2CO3 was added to the melted slag to change the existing form of boron, then the Na4B2O5 and NaBO2 in crystalline phase were precipitated from the Na2CO3-modified slag at high temperature as shown by XRD analysis. Sodium borates thus turned into solution via the water leaching, grinding, filtering and crystallizing of Na2CO3-modified slag and, as a result, borax could be precipitated from the solution at room temperature. Effects of the adding dose of Na2CO3, heat-treatment temperature and particle size of Na2CO3-modified slag on the leaching rate of boron were investigated by chemical analysis and XRD. It was found that the actual adding dose of Na2CO3 is 2.3 times as great as the theoretical one if the Na2CO3-modified slag is treated at 650°C and held for 1.5 hr, and that the highest leaching rate of boron can be up to 76.04% if the particle size of Na2CO3-modified slag is less than 74 μm. References | Related Articles | Metrics

Select

Preparation of Sm-Gd-doped and ceria-based nanopowder Yan, Ping (1); Hu, Xiao-Min (1); Qi, Yang (2) 2009, 30 (12):  1759-1762.  DOI: - Abstract ( 288 )   HTML   PDF (1408KB) ( 529 )   The nanocrystalline ceria-based precursor powder doped with samarium (Sm), gadolinium (Gd) and both of them were prepared separately via a homogeneous precipitation process where the urea and hexamethylenetetramine (HMT) as precipitants with the high-purity reagents Ce(NO3)3·6H2O, Sm2O3 and Gd2O3 as starting materials were both calcined at 700°C for 4.5 hr. Characterizing the phase, morphology, particle size and specific surface area of the products with XRD, SEM and Brunauer-Emmett-Teller (BET), the results showed that both the synthesized powder can be controlled efficiently via controlling the reaction conditions. When the total ion concentration of mixed metal is 0.04 mol/L and the initial concentration of precipitants is 0.5 mol/L with a pH value 6.8, the product from calcined precursor powder presents a single cubic fluorite-type structure with high phase purity and crystallinity, and the size distribution shows that the sphere-like nanopowder particles are in the range from 21 to 28 nm. The synthesized process proposed can yet be regarded as a new reliable approach to preparing the ceria-based electrolytic materials with more homogeneous finer particle size and higher activity at low temperature. References | Related Articles | Metrics

Select

Experimental study on gasification reaction characteristics of coal char with CO2 at elevated temperatures Yu, Qing-Bo (1); Li, Peng (1); Qin, Qin (1); Du, Wen-Ya (1) 2009, 30 (12):  1763-1766.  DOI: - Abstract ( 311 )   HTML   PDF (1102KB) ( 915 )   The char-CO2 gasification reactions at elevated temperature were studied kinetically by the isothermal thermogravimetry using STA409PC thermal analyzer. The effects of coal type, gasification temperature and gas flowrate on gasification reaction were investigated with relevant kinetic parameters calculated. The results showed that when the gasification temperature is lower than the fusion point of char ash, the coal char-CO2 conversion rate and the peak value of reaction rate both increase with increasing gasification temperature. However, when the gasification temperature is higher than the fusion point, the carbon conversion and reaction rates both change so slowly even tend to decrease. The kinetic parameters on gasification reaction with different types of coal char used differ from each other, e.g., the activation energy of coal char used in Ansteel and Bensteel is 140 kJ/mol, while that of the coal char from Fuxin is just 70 kJ/mol. Then, the diffusion becomes the main bottleneck to the gasification reaction if the gasification temperature is higher than the fusion point of char ash. So, increasing the gas flowrate will benefit the char-CO2 gasification reaction. References | Related Articles | Metrics

Select

Preparation of NaGdF4:Eu fluorescent nanoparticles and link between them and biological molecules Yu, Yong-Li (1); Liu, Yan (1); Xu, Shu-Kun (1); Wang, Nai-Zhi (1) 2009, 30 (12):  1767-1770.  DOI: - Abstract ( 462 )   HTML   PDF (697KB) ( 622 )   In order to prepare fluorescent labels which are to be applied to biological analysis, the water-soluble NaGdF4:Eu fluorescent nanoparticles were synthesized by hydrothermal method using gadolinium nitrate, europium nitrate, sodium fluoride and sodium citrate as starting materials. During the synthesis the temperature was controlled at 140°C for 4 hr with the pH value of the reacting solution 8.0. It was found that the fluorescent lifetime of NaGdF4:Eu colloids is 1.144 ms and the fluorescent intensity is high and stable. The synthesized particles were characterized and the IR spectrum shows that the as-prepared particles are coated with citrate. XRD patterns indicate that the synthesized particles are NaGdF4 crystals in hexagonal system and the solid solution is formed via the dopant Eu3+ entering into the NaGdF4 crystal lattice instead of Gd3+, of which the crystal size is about 11 nm. Moreover, the TEM image indicates a good dispersion of the synthesized particles which link the NaGdF4:Eu colloids with tripsin without the change in fluorescent spectra of NaGdF4:Eu colloids, though the particles cause the fluorescence of tripsin to be quenched. The quenching mechanism is discussed. References | Related Articles | Metrics

Select

Simplified analysis of pull-out inclined short fibers Zhao, Li-Jun (1); Huang, Bao-Zong (2); Yuan, Hui-Qun (2) 2009, 30 (12):  1771-1774.  DOI: - Abstract ( 235 )   HTML   PDF (1698KB) ( 427 )   A simplified method was proposed to analyze the bridging force and energy dissipation in the pulling-out process of inclined short fibers from brittle matrix. Coupling the fiber pull-out with matrix spalling and neglecting the local bending of fibers in the interface debonding process before fiber pull-out and in the pull-out section, some nonlinear control equations were given to the fiber pull-out process with an iteration method to solve them. In this way the relationship between bridging force and opening displacement during short fiber pull-out was given, as well as the effects of such parameters as pull-out energy, interface friction stress, inclination angle and fiber length on the pull-out process. Simulation results showed that the matrix spalling can increase the pull-out force of fibers and change the relationship between pull-out force and displacement and, what's more, a conclusion is drawn that choosing appropriately the interface friction and length of fibers will significantly increase the pull-out energy dissipation. References | Related Articles | Metrics

Select

Componential operation based enterprise application integration for innovative design Cui, Dong-Liang (1); Feng, Guo-Qi (3); Zhang, Yao-Peng (4) 2009, 30 (12):  1775-1779.  DOI: - Abstract ( 262 )   HTML   PDF (3410KB) ( 433 )   Considering the requirements for the innovative design of complex product, a comprehensive technology for componential operation was proposed including the technical means applied in enterprise's engineering design data/process. Based on the previously realized technologies for design, such as software registration, parameter parsing and data mapping, a plug-and-play mode for heterogeneous application packages was designed to implement the evolutionary management of the componential operation at different levels. The configuration for implementing componential operation was designed on the basis of MS-COM technique, which is available to implement the management of componential operation by instance and project management with a process template as core. A multi-view framework for EAI was therefore given to implement the trans-project data management in accordance to the process template. The valid of the method proposed was verified via an exemplification of computation of aircraft flight loads. References | Related Articles | Metrics

Select

Mobile robot control system based on cricket wireless localization Guo, Li-Xin (1); Huang, Qiu-Ye (2); Luo, Zhong (1) 2009, 30 (12):  1780-1783.  DOI: - Abstract ( 529 )   HTML   PDF (763KB) ( 835 )   The localization of mobile robots is the precondition and key to the navigation control of mobile robots. Combining the technology of Cricket wireless localization with mobile robot control system, a robot control system based on the localization of wireless sensor networks was developed to complete the information transmission/incorporation between the Cricket localization system and mobile robot system and implement the localization and navigation control of the mobile object. The Cricket system exhibits high precision in localization with the error of sampling data fluctuating within 3 cm under static condition. The system time delay is around 60 ms when the mobile object changes its location at a relative rapid speed. References | Related Articles | Metrics

Select

Fault diagnosis based on EMD and fuzzy clustering for diesel engine Wu, Zhen-Yu (1); Yuan, Hui-Qun (1); Li, Shen (1) 2009, 30 (12):  1784-1787.  DOI: - Abstract ( 259 )   HTML   PDF (1126KB) ( 527 )   According to the traits of fault vibration signals from a diesel engine, a new method was presented for the fault diagnosis of the signals based on EMD(empirical mode decomposition) and FCM(fuzzy c-means clustering). The time series of vibration signals of three different air valve clearances (0.4, 0.6 and 0.75 mm) was decomposed via EMD, then the energy ratios in percentage of the first six intrinsic modal functions obtained by EMD were calculated separately, and the relevant energy ratios were taken as the characteristic parameters reflecting what state the fault is in. Those parameters were analyzed by FCM algorithm. Experiments indicated that the diagnosed results of all samples conform to actualities, i.e. the method can effectively diagnose the faults of air valve clearance of a diesel engine. References | Related Articles | Metrics

Select

Stress analysis of BF hearth and lining and reinforcement criterion for longitudinally cracked shell Chen, Liang-Yu (1); Li, Yu (1); Li, Sheng-Long (1) 2009, 30 (12):  1788-1791.  DOI: - Abstract ( 241 )   HTML   PDF (1726KB) ( 440 )   According to the linear thermoelasticity and the mechanical characteristics of blast furnace hearth due to thermal expansion, the formulae to calculate the stress and deformation of BF hearth are deduced under the conditions that 2-D temperature distribution is axisymmetric and the pressure distribution is uniform. Analyzing the stress of BF hearth in overheating state and that of furnace lining before and after reinforcing the longitudinally cracked furnace shell, the lining strength resulting from the control of its outside tensile strength is obtained. Then, the minimum interface pressure meeting the strength requirement is derived from the outside surface strength of furnace lining, thus providing the conceptual design for reinforcing the longitudinally cracked furnace shell with a criterion for the reinforcement. A numerical example is given as reference for relevant calculation. References | Related Articles | Metrics

Select

Improved collaborative filtering recommendation based on customers' transaction data Zhao, Xiao-Yu (1); Huang, Xiao-Yuan (1); Cao, Zhong-Peng (1) 2009, 30 (12):  1792-1795.  DOI: - Abstract ( 267 )   HTML   PDF (365KB) ( 817 )   Discussing the limitation of data source in conventional collaborative filtering recommendation (CFR), which is widely used in B2C E-commerce websites, an improved CFR based on customers' transaction data is put forward. The fundamentals of the improved CFR are described as follows. The three customers' behavioral indices including the recency (R), frequency (F), and monetary (M), are acquired from customers' historical records of shopping for various goods to evaluate their purchasing preferences, and then an integrated RFM (IRFM) matrix is formulated as the data source of CFR to recommend personalized goods for target customers, thus providing a high-quality recommendation to familiar customers so as to expand the application range of CFR. References | Related Articles | Metrics

Select

Application of GIOWA operator to evaluation of CEOs' strategic leadership Ren, Rong-Rong (1); Xing, Gang (1) 2009, 30 (12):  1796-1799.  DOI: - Abstract ( 236 )   HTML   PDF (335KB) ( 451 )   Ambiguity and difficulty in quantification characterize the evaluation of CEOs' strategic leadership in China. An evaluation index system is therefore developed including five strategic abilities, i.e. wishful foresight, decision making/performing, public relations, analysis-making and execution. Also, an appraising scale is defined for language in the evaluation index system with an expression of triangular fuzzy numbers given correspondingly. Then, a generalized induced ordered weighted averaging (GIOWA) operator is used for aggregation to complete the evaluation of CEOs' strategic leadership. The evaluation index system provides an objective reference for the selection, check-up and training of CEOs, and its validity is verified via empirical example. References | Related Articles | Metrics

Select

On the theorems of altman-type fixed point Zhang, Guo-Wei (1); Shan, Shan (1) 2009, 30 (12):  1800-1802.  DOI: - Abstract ( 202 )   HTML   PDF (122KB) ( 626 )   The theorems of Altman-type fixed point are studied. The existence of the fixed point of completely continuous operator is discussed under the norm inequality conditions that the first exponent is between 0 and 1, the second one is not greater than 0 and there is only one exponent that is less than 0. Some new fixed point theorems are proved. In contrast to the fixed point theorems as shown in earlier works where the first exponent is greater than 1 and the second one is not less than 0 under the norm inequality conditions, some supplements are given to those theorems. References | Related Articles | Metrics