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Information & Control

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A Robust Consensus Algorithm for Multirobot Systems〓 JIANG Yulian， LIU Jianchang， TAN Shubin， WANG Shenquan 2014, 35 (8):  1065-1068.  DOI: 10.12068/j.issn.1005-3026.2014.08.001 Abstract ( 783 )   HTML   PDF (402KB) ( 815 )   For a multirobot system subjected to exogenous disturbance and with partial information given， a robust consensus algorithm is developed to solve the output consensus problems. The kinematic model of a differential wheeled mobile robot is presented first. According to the idea of combining global control with local control， the consensus based on a multiagent system is mathematically described. Then， a reasonable robust performance index is proposed， and utilizing H∞ robust control and differential game theory， a robust consensus algorithm is designed. An example is simulated to demonstrate that the proposed method can guarantee the velocity consensus autonomously for each robot and restrain disturbance. References | Related Articles | Metrics

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A FractionalOrder Kalman Filter〓 LIU Lu， PAN Feng， XUE Dingyu 2014, 35 (8):  1069-1072.  DOI: 10.12068/j.issn.1005-3026.2014.08.002 Abstract ( 1243 )   HTML   PDF (430KB) ( 1831 )   A conventional Kalman filter is suitable for integerorder systems. In order to apply the Kalman filter to fractionalorder systems， a statespace expression defined by discrete fractionalorder calculus is introduced into the conventional Kalman filter， thus a fractionalorder Kalman filter algorithm is proposed. A simulation experiment is carried out， with two state variables and one output signal as research objects. The fractionalorder Kalman filter module is designed in MATLAB. The states of the system are estimated by the input variables and the output variable with noise， showing that the fractionalorder Kalman filter algorithm proposed has satisfactory filtering and stateestimating capacity. References | Related Articles | Metrics

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A Modified Harmony Search Algorithm with Global Crossover〓 WANG Hao， GAO Liqun， OUYANG Haibin， QIN Wei 2014, 35 (8):  1073-1076.  DOI: 10.12068/j.issn.1005-3026.2014.08.003 Abstract ( 719 )   HTML   PDF (349KB) ( 594 )   To improve the global search ability of a harmony search algorithm， a modified one with global crossover (MHSgc) was proposed. In the MHSgc， the collaborative improvisation of multipleharmonymemory was applied. A neighborlearning strategy replaced the intrinsic pitch adjusting，and thus the population diversity was increased. Moreover， global crossover operation was introduced into the MHSgc algorithm to avoid getting stuck into local minima. Simulations were carried out based on several benchmark functions. The results show that the proposed algorithm outperforms eight intelligent algorithms (IHS， GHS， NGHS， EHS， ITHS， MPSO， DE， ABC) reported in earlier literatures and has better optimization potential. References | Related Articles | Metrics

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Optimal Design of Eccentric Magnetic Pole for Permannent Magnet Drive〓 SHI Songning， WANG Dazhi， SHI Tongyu 2014, 35 (8):  1078-1082.  DOI: 10.12068/j.issn.1005-3026.2014.08.004 Abstract ( 745 )   HTML   PDF (684KB) ( 662 )   A permanent magnet drive (PMD) with eccentric magnetic pole was designed. The sample space was built by 3D finite element simulation， and a nonlinear regression model of the PMD was developed using the least squares support vector machine (LSSVM). Based on the model， the minimal eddy current loss and maximal output torque were selected as optimal objectives. The optimal parameters of the PMD were then derived through particle swarm optimization (PSO) searching. The results show that the parameter optimization method based on LSSVM and PSO algorithms is feasible by comparing the radial magnetic flux and eddy current densities of the improved PMD with that of the intrinsic one. The improved structure of the eccentric magnetic pole optimizes eddy current path and reduces stray current， thus increases the work efficiency. References | Related Articles | Metrics

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Optimal Capacity and Scheduling Policy for Appointment System with Walkin Demand〓 YAN Chongjun， TANG Jiafu， JIANG Bowen 2014, 35 (8):  1083-1087.  DOI: 10.12068/j.issn.1005-3026.2014.08.005 Abstract ( 626 )   HTML   PDF (477KB) ( 713 )   The joint capacity and appointment schedule with walkin demands were modeled. The objective function was proved to be multimodular when the service time follows an exponential distribution and the cost function is a monotonically increasing convex function. Based on multimodular function， a neighborhood search algorithm converging to optimal solution was proposed to determine booking limits and schedule with maximizing utility. Numerical experiments were conducted to analyze the effects of system parameters on optimal utility and of walkin demands on the design of appointment system. The results indicate that the optimal schedule overbooks the first slot， and the walkin demand reduces the utility of the appointment system in most scenarios. References | Related Articles | Metrics

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Bed Allocation in Nobuffer Tandem Queuing System with Blocking for Healthcare Unit〓 ZHU Huabo， TANG Jiafu， GONG Jun 2014, 35 (8):  1088-1092.  DOI: 10.12068/j.issn.1005-3026.2014.08.006 Abstract ( 650 )   HTML   PDF (349KB) ( 728 )   The behavior of patients flow in a hospital where the patients sequentially pass through a set of healthcare units is analyzed. Focusing on hospital bed allocation， a nobuffer tandem queuing system with blocking is modeled， with the performance indicators such as patients’ waiting time and bed occupancy rate given. The blocking probability of the system is derived by an approximation method. A mathematical programming model with bed cost constraints is developed to determine how many beds are assigned to each stage/division to minimize the system blocking probability. And a neighborhood search combined with simulated annealing (NSSA) is developed to solve the model. The influences of the bed allocation and the weight of beds on blocking probability are investigated. Numerically experimental results are compared with the results in different literatures， showing the superiority of the proposed method. References | Related Articles | Metrics

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Cooperative Scheduling Optimization in Airport Shuttle Service Based on Multivehicles〓 XU Zhengzheng， YU Yang， TANG Jiafu 2014, 35 (8):  1093-1096.  DOI: 10.12068/j.issn.1005-3026.2014.08.007 Abstract ( 710 )   HTML   PDF (441KB) ( 734 )   Focusing on the airport shuttle service based on multivehicles， the cooperative scheduling model taking the minimum total mileages driven as the objective is built， and a heuristic optimization algorithm is proposed to solve the model. The pickup points which need a vehicle to offer individual shuttle service， namely isolated points，are determined after basic routes are planned. Then the cooperative patterns between isolated points and basic routes， between remaining routes and basic routes cooperating with isolated points， as well as between final remaining routes are taken into account respectively. The vehicle scheduling scheme based on the cooperation is obtained. Numerical experiments show that the proposed cooperative model and optimization algorithm can effectively decrease the operation cost in the airport shuttle service. References | Related Articles | Metrics

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Crowdsourcing Quality Evaluation Strategies Based on Voting Consistency 〓 YUE Dejun， YU Ge， SHEN Derong， YU Xiaocong 2014, 35 (8):  1097-1101.  DOI: 10.12068/j.issn.1005-3026.2014.08.008 Abstract ( 748 )   HTML   PDF (423KB) ( 1209 )   A dynamic evaluation strategy for the worker precision based on the voting consistency is proposed. The crowdsourcing task set is divided into multiple task subsets and each of them is regarded as a task phase. When a task phase is finished， the whole votes and the number of the worker’s voting value agreeing with the working group’s one are recorded. Then， the workers’precision is evaluated and the unqualified workers are detected. All the unqualified workers are dynamically replaced to ensure that the correct rate of the group exceeds the task accuracy threshold. The effectiveness of the proposed method is evaluated using three realworld datasets， which shows that the method can achieve good performance. References | Related Articles | Metrics

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An Adaptive Ant Colony Classification Algorithm〓 MA Anxiang， ZHANG Changsheng， ZHANG Bin， ZHANG Xiaohong 2014, 35 (8):  1102-1106.  DOI: 10.12068/j.issn.1005-3026.2014.08.009 Abstract ( 699 )   HTML   PDF (397KB) ( 591 )   Taking classification learning as an optimization problem of seeking for optimal classification rules， an adaptive ant colony algorithm， adaptive L_AMP， is proposed to solve classification problem and get the comprehensible classification rules. In the rulebased classification methods， the way of choosing of a ruleevaluating function is important. The adaptive L_AMP proposed can be used to automatically select an appropriate ruleevaluating function according to the data set， thus improving the classification correctness. Moreover， a local search technique is introduced into the algorithm proposed. The algorithm is run on the real data set and compared with other relevant algorithms. The results show the superiority of the algorithm proposed. References | Related Articles | Metrics

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Web Service Selection Based on Modified Ant Colony Optimization SHENG Guojun， WEN Tao， GUO Quan， YIN Ying 2014, 35 (8):  1107-1111.  DOI: 10.12068/j.issn.1005-3026.2014.08.010 Abstract ( 514 )   HTML   PDF (460KB) ( 592 )   Focusing on Web service selection problem， a new modified ant colony optimization (ACO) algorithm is proposed. Both a nonlinear dynamic parameter of the pseudorandom proportion selection rule and a multipleoptimalsolution randomweighted route selection algorithm are employed in the algorithm proposed to control the behavior of ant colony. Besides， a fivedimensional service quality vector and the fitness function are used in the algorithm to evaluate the ant solutions， and each ant updates the pheromone according to the quality of their solutions they built. With these measures， the evolution ability of ant colony can be significantly improved. The experimental results show that the proposed algorithm outperforms traditional ACO algorithms. References | Related Articles | Metrics

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Morphological Analysis of Ventricular Septum Based on Medical Images〓 ZHANG Yaonan， ZHU Jiangyuan， XU Yu， KANG Yan 2014, 35 (8):  1112-1116.  DOI: 10.12068/j.issn.1005-3026.2014.08.011 Abstract ( 577 )   HTML   PDF (478KB) ( 570 )   Ventricular wall skeleton and endocardial boundary were extracted from cardiac MRIs using medical image segmentation and morphological image processing methods. Then， the endocardial morphology was analyzed automatically by the key parameters that can describe the morphology of ventricular septum. An algorithm was proposed to automatically calculate the curvature of ventricular septum skeleton， and the concept of ventricular septum offset was presented to make up for the deficiency of describing the ventricular septum by the curvature，thus improving the imagebased evaluation method of ventricular septum morphology. Experimental results demonstrate that the curvature， offset and endocardial boundary can be used as key parameters to evaluate the shape of ventricular septum. References | Related Articles | Metrics

Materials & Metallurgy

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Effect of Nb on Continuous Cooling Transformation Behavior of Low Carbon Microalloyed Steel〓 WANG Zhuangfei， TANG Shuai， LIU Zhenyu， WANG Guodong 2014, 35 (8):  1117-1119.  DOI: 10.12068/j.issn.1005-3026.2014.08.012 Abstract ( 676 )   HTML   PDF (498KB) ( 766 )   The dynamic continuouscoolingtransformation (CCT) diagrams of Nbfree and 0042 wt% Nb tested steels were plotted by means of a dilatometry method combined with metallography. The influence of Nb on the continuous cooling transformation behavior and transformation microstructure of low carbon microalloyed steel was elucidated. The results show that the addition of Nb can significantly refine ferrite grain size and suppress the formation of ferrite， promoting the formation of bainite， and can make CCT curves move down and right， reducing the ferrite and perlite transformation field and expanding the bainite transformation field. Moreover， the Vickershardness can be significantly increased due to grain refinement， precipitation hardening and transformation strengthening by the addition of Nb. References | Related Articles | Metrics

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Effects of Coiling Temperature on Microstructure and Mechanical Properties of HotRolled Ferrite/Bainite Dual Phase Steel〓 SHEN Xinjun， PEI Xinhua， TANG Shuai， WANG Guodong 2014, 35 (8):  1120-1123.  DOI: 10.12068/j.issn.1005-3026.2014.08.013 Abstract ( 877 )   HTML   PDF (530KB) ( 718 )   The process of aircooling followed by ultra fast cooling after hotrolling was used to investigate the effects of coiling temperature on the microstructure and mechanical properties of a ferrite/bainite (F/B) dual phase steel. The results show that the volume fraction and the grain size of ferrite are in the rage of 857%-878% and 36-37 μm， respectively， almost independent of the coiling temperature. Lowering coiling temperature from 504 ℃ to 250 ℃， the dominant hard phase was transformed from bainite to martensite， resulting in the ultimate strength up to 597 MPa from 510 MPa， the yield strength down to 389 MPa from 475 MPa， but the elongation without significant change (322%-350%). Besides， the deformation compatibility between ferrite and bainite or martensite is weakened with the decrease of the coiling temperature， which induces the nucleation in advance， accelerates growth and coalescence of microvoids， so the hole expansion property is deteriorated and the hole expansion ratio is reduced from 1014% to 524%. References | Related Articles | Metrics

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Influence of Grain Size on the Corrosion Resistance of Medium Chromium Ferritic Stainless Steel Containing Cu and Sn〓 ZHANG Xiangjun， SHEN Xinjun， ZHANG Shumin， LIU Zhenyu 2014, 35 (8):  1124-1127.  DOI: 10.12068/j.issn.1005-3026.2014.08.014 Abstract ( 698 )   HTML   PDF (577KB) ( 715 )   The corrosion test of ultra purified 165 wt%Cr ferritic stainless steel containing Cu and Sn was carried out by immerging the specimens into the 6 wt% FeCl3 solution at 35 ℃， and the polarization curves of the steel were measured using potentiodynamic polarization method. The influence of grain size on the corrosion resistance of ferritic stainless steel was investigated. The corrosion rates were calculated through gravimetric tests. The results show that the pitting potential of the stainless steel greatly rises with the coarsening of grain size. There is a relative reasonable range of grain size and overfined or overcoarsened grain size are unbeneficial for the corrosion resistance of the tested steel. References | Related Articles | Metrics

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Hot Deformation Behavior of 50Mn18Cr4V Nonmagnetic Steel MA Biao， SONG Yanlei， ZHENG Jianjun， LI Changsheng 2014, 35 (8):  1128-1132.  DOI: 10.12068/j.issn.1005-3026.2014.08.015 Abstract ( 768 )   HTML   PDF (1120KB) ( 742 )   The hot deformation behavior of 50Mn18Cr4V nonmagnetic high manganese steel within the strain rates of 01-10 s-1 and deformation temperatures of 900-1 100 ℃ was studied by high temperature uniaxial compression tests. The results show that straininduced precipitation of VC particles has an important effect on the hot deformation behavior of the tested steel. When the deformation temperature is 900-1 000 ℃ and the strain rate is 5 s-1， the precipitation of VC is insufficient and then the suppression of dynamic recrystallization is weakened， compared with that at the strain rate of 1 s-1. It is better for the total reduction to be accomplished in relatively higher temperature regions with an appropriate strain rate. As the deformation temperature decreases below 950 ℃， the hot plasticity is poor so that the thermal cracking prefers to occur at lower strain rates and the tendency of flow instability increases at higher strain rates. Accordingly， the optimized strain rate is 5 s-1 during hot working process. Furthermore， the activation energy of the tested steel is 7769 kJ/mol for hot deformation. The mathematic model of deformation resistance at high temperature was also established. References | Related Articles | Metrics

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Microstructure and Its Influence on Helium Bubbles in Nanostructured 9CrODS Steel LU Chenyang， LYU Zheng， LI Yunpeng， LIU Chunming 2014, 35 (8):  1133-1136.  DOI: 10.12068/j.issn.1005-3026.2014.08.016 Abstract ( 788 )   HTML   PDF (929KB) ( 1029 )   A 9CrODS steel was prepared by mechanical alloying and hot isostatic pressing methods. The microstructures were characterized by highresolution transmission electron microscopy and highangle annular dark field scanning transmission electron microscopy (HAADFSTEM). Helium ions of 4×1017/cm2 were respectively implanted into the 9CrODS steel and nonODS Eurofer97 steel with a 400keV ion accelerator， and the sizes of helium bubbles in the two steels were observed by HAADFSTEM. The results show that the average grain size of the 9CrODS steel is about 05μm. Two kinds of precipitates were observed in the ODS steel: highdensity nanosize Y2Ti2O7 and large Mn(Ti)Cr2O4 formed mainly at the grain boundaries. The size of the helium bubbles in ODS steels is much more smaller than that in Eurofer97 steel， which means that the nanosize precipitates are helpful to suppress the formation of coarse helium bubbles. References | Related Articles | Metrics

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Exit Velocity Uniformity of Water Supply Pipe and Nozzle Manifolds in Advanced Cooling System XIE Qian， HU Xiao， WANG Zhaodong， WANG Guodong 2014, 35 (8):  1137-1140.  DOI: 10.12068/j.issn.1005-3026.2014.08.017 Abstract ( 709 )   HTML   PDF (951KB) ( 684 )   The flow field of the nozzle manifolds and water supply pipes in an advanced cooling system was analyzed by the finite element method according to field data. The flow states of nozzle manifolds were compared under the conditions of different diameters and different inlet flow velocities of distribution pipes， thus the optimal diameter of the distribution pipe was obtained to satisfy the demand of nozzle manifolds， which guarantees the uniform flow state of nozzle manifolds. In addition， the steady flow state of multilayer damping nozzle manifold was studied. Within the equipment capacity， the outlet flow velocities of nozzle manifolds were uniform， with the standard deviation ranging from 00982 to 02692. References | Related Articles | Metrics

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Modeling of Recrystallization for Material with Precipitated Fine Particles by Cellular Automaton Method GUAN Xiaojun， MA Xiaofei 2014, 35 (8):  1141-1146.  DOI: 10.12068/j.issn.1005-3026.2014.08.018 Abstract ( 642 )   HTML   PDF (1164KB) ( 848 )   In order to rationally simulate the recrystallization process of the material with secondphase particles， a cellular automata model for recrystallization of singlephase material with tiny second phase particles was created by introducing the Zener force to resist subgrain growth and the rule of cell orientation transformation of grain boundary pinning， and the recrystallization annealing process of a ferritic steel was simulated. The results show that the model fully consider the combined effects of recovery at variable temperature， nonuniform deforming storage energy， abnormal nucleation and growth of subgrain， and impeding by fine particles on recrystallization， and the simulated microstructure evolutions and their dynamics analysis reveals the same laws both in theories and in practice， that is， the smaller is particle size and the more is its number， the stronger is the effect of inhibiting recrystallization and the longer are the incubation period and the process of recrystallization. References | Related Articles | Metrics

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Optimization of BF Slag System for VanadiumTitanium Magnetite by Comprehensive Weighted Scoring Method CHU Mansheng， FENG Cong， TANG Jue， LIU Zhenggen 2014, 35 (8):  1146-1150.  DOI: 10.12068/j.issn.1005-3026.2014.08.019 Abstract ( 603 )   HTML   PDF (828KB) ( 625 )   The components of practical blast furnace(BF) slag of vanadiumtitanium magnetite provided by a domestic enterprise were adjusted by adding pure chemical reagents under laboratory conditions， then the five factors in four levels orthogonal experiment was carried out and the metallurgical properties of slag samples were investigated using RTW melt property tester. Finally， through the comprehensive weighted scoring method， the suitable BF slag system for smelting vanadiumtitanium magnetite was obtained as follows: binary basicity was 115， the content of MgO， Al2O3， TiO2 and V2O5 was 14%， 13%， 7% and 020%，respectively. Besides， the order of each factor affecting comprehensive indexes of slag system was the V2O5 content， MgO content， binary basicity， TiO2 content and Al2O3 content. References | Related Articles | Metrics

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Effects of Electromagnetic Casting on Microstructures and Distribution of Alloying Elements of Goldbased Alloy ZHANG Qin， ZHANG Junkai， LI Ying 2014, 35 (8):  1151-1153.  DOI: 10.12068/j.issn.1005-3026.2014.08.020 Abstract ( 643 )   HTML   PDF (649KB) ( 594 )   In order to enhance the property of goldbased alloy coating， AuCu system gold alloys with additions of multialloying elements for making vacuum sputtering target were prepared by electromagnetic casting and conventional die casting respectively. The effects of electromagnetic field on the ascast microstructure and the distribution of the alloying elements of the gold alloy were investigated. The results show that the solidification structure of the goldbased alloy billets prepared by electromagnetic casting is more uniform and smaller than that by conventional die casting. Meanwhile， the macrosegregation of the alloying elements of the gold alloy is also restrained to a great degree. Furthermore， the effects of electromagnetic field on the refinement mechanism of solidification structure and distribution of alloying elements were also discussed. References | Related Articles | Metrics

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High Temperature Performance of Coke Formed from COREX Coal LIU Qihang， WU Keng， ZHAN Wenlong， REN Hailiang 2014, 35 (8):  1155-1160.  DOI: 10.12068/j.issn.1005-3026.2014.08.021 Abstract ( 682 )   HTML   PDF (603KB) ( 584 )   By observing different coal char’s microstructures and microscopic morphologies during the coking process， the characteristics of COREX coal char’s microstructure and properties were analyzed. MCRI and MCSR were used to describe the reactivity and the strength after reaction of coal char respectively， with those of BF’s coke for reference， then the physical meaning of MCRI and MCSR were given. MCRI and MCSR were determined by the composition of coal char. For the two kinds of COREX coal， the formula to forecast the hot performance of coal char was set up by making a multiple linear regression between the hot performance and microstructure of the coal char at 1100℃， and the predictive values of coal char’s hot performance at 600， 800 and 1000℃ coincided well with the measured values. References | Related Articles | Metrics

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Control Model of Effective Ti Content for Hearth Protection by TitaniumBearing Material JIAO Kexin， ZHANG Jianliang， ZUO Haibin， LIU Zhengjian 2014, 35 (8):  1160-1163.  DOI: 10.12068/j.issn.1005-3026.2014.08.022 Abstract ( 708 )   HTML   PDF (443KB) ( 940 )   The titaniumbearing material reduction behavior and the protection mechanism for a hearth were analyzed， based on which， the control model of the effective Ti content was established. The effective TiO2 content， critical Ti content with which TiC precipitated and the corresponding precipitation temperature could be calculated by the model according to the realtime parameters of the BF in the actual production in order to guide the production practice. Given the production parameters， the calculated results showed that the effective TiO2 content should be 08 wt%-10 wt%， and the Ti content in molten iron， in which the hearth could be effectively protected， should be 011 wt%-014 wt%. Furthermore， the influence of hot metal ingredients on the precipitation of TiC was analyzed. References | Related Articles | Metrics

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Novel Process for Comprehensive Utilization of HighIron Bauxite XIN Haixia， WU Yan， TENG Fei， ZHAI Yuchun 2014, 35 (8):  1165-1168.  DOI: 10.12068/j.issn.1005-3026.2014.08.023 Abstract ( 667 )   HTML   PDF (567KB) ( 698 )   The bauxite was characterized by Xray diffraction (XRD) and scanning electron microscopy (SEM)， and the main phase and morphology of the raw material were determined. Aluminum， iron and silicon can be effectively separated by low temperature sulfuric acid roasting process. The effects of process parameters on the extraction rates of aluminum and iron were investigated experimentally. When the amount of sulfuric acid is 12 times as the amount of theory， the extraction rates of aluminum and iron are above 92% at 350℃ for 60min. Most of the iron in the filtrate was deposited by natrojarosite method， and the iron precipitation rate could reach more than 90%， with the aluminum deposition rate controlled within 5%. References | Related Articles | Metrics

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Roasting of Low Grade Zinc Oxide Ore by Concentrated Sulfuric Acid WANG Le， MU Wenning， LIU Shaoming， ZHAI Yuchun 2014, 35 (8):  1169-1173.  DOI: 10.12068/j.issn.1005-3026.2014.08.024 Abstract ( 612 )   HTML   PDF (580KB) ( 747 )   Zn， Fe and Al were extracted from low grade zinc oxide ore obtained from China by the new technique of concentrated sulfuric acid roasting. The effects of reaction temperature， reaction time and molar ratio of acid to ore on extraction rate of Zn， Fe， Al were investigated. Microstructures and components of the zinc calcine and tailing were characterized by scanning electron microscope (SEM) and Xray diffraction (XRD) analyzer. On the basis， the optimum reaction condition was obtained through orthogonal tests. Results showed that the extraction rates of Zn， Fe and Al were 9902%， 2378% and 7768% respectively， when the ores were roasted for 120min at 6735K and molar ratio of acid to ore was 16∶1. The elements of Si， Ca and Pb were enriched in the residue. Related Articles | Metrics

Mechanical Engineering

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Research and Design of a Novel Inspection Robot with Multiunit Mechanisms in Series FANG Lijin， TAO Guanghong 2014, 35 (8):  1173-1177.  DOI: 10.12068/j.issn.1005-3026.2014.08.025 Abstract ( 507 )   HTML   PDF (1587KB) ( 679 )   Regarding the working task requirement of inspection robot and the rugged surroundings of high voltage transmission line， a novel inspection robot with multiunit mechanisms in series was designed. Each unit mechanism was composed of two parallelogram mechanisms in series. Based on the obstaclecrossing mechanism of the robot and the types of obstacles over the transmission line， prime structure parameters and four representative obstaclecrossing modes of the robot were provided. The workspace of the robot was analyzed for the typical crossing mode. The analysis results show that the robot has ability to cross typical obstacles over the 500kV transmission line， the robot mechanisms with multiunit in series can meet the requirements of crossing obstacles and turning on the transmission line which has certain inclination. References | Related Articles | Metrics

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Turning TimeDomain Simulation Based on Numerical Integration LIU Yu， LI Qingxiang， ZHANG Yimin 2014, 35 (8):  1179-1183.  DOI: 10.12068/j.issn.1005-3026.2014.08.026 Abstract ( 618 )   HTML   PDF (571KB) ( 706 )   A single degree of freedom dynamic model in z direction for turning machine system was established. The frequency response function of the tool holder of CJ0625 turning machine was obtained through the hammer test， with the dynamic parameters identified. The timedomain simulation was conducted using a variable stepsize method that can dynamically adjust the stepsize according to the spindle speed and thus ensure the algorithm convergence and required accuracy. The software for the timedomain simulation of the turning process was designed and written based on the Matlab platform. The timedomain solution method was compared with the frequency domain flutter prediction method (stability lobe diagram)， and the displacement vs time history curves of vibration were given under the conditions of stable cutting， critical stable cutting and unstable cutting. The results show that the errors of absolute stable cutting widths determined using these two methods are both below 607%. References | Related Articles | Metrics

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Deadlock Recovery Algorithm for Unified AMHS in Semiconductor FAB ZHOU Qi， ZHOU Binghai 2014, 35 (8):  1183-1188.  DOI: 10.12068/j.issn.1005-3026.2014.08.027 Abstract ( 697 )   HTML   PDF (844KB) ( 640 )   To recover from deadlocks which occur in bufferconstrained tools in the united automatic material handling system of 300mm semiconductor wafer fabrications， a twostage algorithm based on the graph theory was proposed. The mentioned deadlock problems were formulated， and then sufficient conditions of the deadlock happening and recovery were determined. A mathematical programming model was set up with the objective function of minimizing the deadlock recovery time of critical tools， and a heuristic algorithm for deadlock recovery was put forward. A stocker’s buffer was used to stock wafer lots to release deadlocked resources， and several parallel routes according to the graph theory were constructed to recover from deadlock. Simulation results indicated the effectiveness of the proposed method. It can reduce average deadlock recovery time and improve the utilization of critical tools， compared with other methods. References | Related Articles | Metrics

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Principle and Design of Noncircular PinCycloid Gear Transmission LIN Chao， WANG Yantao 2014, 35 (8):  1190-1194.  DOI: 10.12068/j.issn.1005-3026.2014.08.028 Abstract ( 893 )   HTML   PDF (920KB) ( 2043 )   Noncircular pincycloid transmission is proposed， which can implement variable gear ratio transmission between parallel axes. The meshing coordinate system of the noncircular pincycloid gears is set up， with the forming principle of the conjugate profile described. The tooth profile equation of the noncircular pin gear is established， then that of the cycloidal gear is derived through coordinate system transformation， based on the conjugate tooth profile theory， the circular pin gear cutting tool profile equation， and the noncircular pin gear cutting tool path and mesh equation. The parametric design of the gear pair is obtained by Matlab program. The design example of the noncircular pincycloid gear is achieved. And the three dimension model is established by SolidWorks. Based on the kinematics analysis of the noncircular pincycloid drive by Adams software， the validity of the principle and design of noncircular pincycloid drive is verified through the contrast analysis between the experimental and theoretical arithmetic results. References | Related Articles | Metrics

Resources & Civil Engineering

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Improved Optimization Algorithm of Ultimate Pit for Open Pit Metal Mine XU Xiaochuan， GU Xiaowei， WANG Qing， LIU Jianping 2014, 35 (8):  1195-1198.  DOI: 10.12068/j.issn.1005-3026.2014.08.029 Abstract ( 711 )   HTML   PDF (376KB) ( 637 )   The overlapping problem in cones is an inherent defect for cone elimination method in optimizing ultimate pit. In view of this， diminishing vertical scan step is used to improve cone elimination algorithm and the step are set as one， half and one quarter of the block height. According to the actual conditions of ore deposits， an appropriate step or combination step is chosen for some mine optimization to improve optimization accuracy. The results of three example applications show that， under the same condition of technical and economic parameters， the ultimate pits produced by improved elimination algorithm are better than those by conventional algorithm. The profits of three mines grow by RMB 217， 417， and 2333 million， respectively. References | Related Articles | Metrics

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Coupling Effect of Top Smoke Discharging and Water Mist on Characteristics of Fire Smoke ZHANG Peihong， TIAN Xiangliang， ZHANG Yi， JI Tingchao 2014, 35 (8):  1199-1202.  DOI: 10.12068/j.issn.1005-3026.2014.08.030 Abstract ( 750 )   HTML   PDF (964KB) ( 731 )   A tunnel model(6m×15m×2m) was designed to do the firesuppression experiment under the joint action of top smoke discharging and water mist. The temperature of the smoke and flame， the concentration of CO， as well as the visibility of smoke were measured to analyze the suppression and cooling effect on fire and smoke under different coupling modes of water mist and top smoke discharging. The results show that top smoke discharging accelerates the burning rate of diesel oil， and cooling effect is obvious under the coupling mode. In the fire growth stage (50s)， water mist coupled with top smoke discharging has the optimal control effect on smoke. Whereas it is easy to lead boil over and flashover in the fire fullydeveloped stage (90s). Meanwhile， the flame enhancement is most obvious and the concentration of CO increases sharply. Top smoke discharging can greatly improve the visibility， and water mist alone can control the smoke effectively but decrease the visibility. The increasing rate of visibility can be accelerated because of the sedimentation of smoke absorbed by water mist combined with top smoke discharging. References | Related Articles | Metrics

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Research of Shenyang Real Estate Market Based on Generalized Regression Neural Network ZHAO Liang， WANG Lianguang， QI Xijing 2014, 35 (8):  1203-1205.  DOI: 10.12068/j.issn.1005-3026.2014.08.031 Abstract ( 571 )   HTML   PDF (380KB) ( 554 )   Based on the relevant data of Shenyang real estate market from 2003 to 2009， the data from 2010 to 2011 were forecasted using the generalized regression neural network with a smoothing factor of 01 which has excellent approximation， and were compared with the true data. The results show that the developing investment， housing average price， and vacant areas of the real estate in Shenyang are in high level. Moreover， the real estate market is still in the boom， but belongs to the later period. Government， developer， and home buyer should pay attention to the real estate bubbles which may emerge in the future. References | Related Articles | Metrics

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Durability Assessment of Highway Bridges Based on Information Entropy and Uncertainty Measurement Theory ZHENG Yifeng， LI Long， FANG Wei， GAO Xin 2014, 35 (8):  1206-1211.  DOI: 10.12068/j.issn.1005-3026.2014.08.032 Abstract ( 551 )   HTML   PDF (447KB) ( 647 )   Based on information entropy and uncertainty measurement theory， a model was developed to evaluate and sort the durability of bridges. First， the assessment index system and singleindex measurement functions were determined on the basis of Standards for Technical Condition Evaluation of Highway Bridges. Then， the evaluation matrix of singleindex measurement was achieved according to the field data. The weights of these indices were obtained from the information entropy theory， and the multipleindex measurement vector was calculated. Finally， the durability grade was assessed with credible recognition criteria. The durability of the threespan superstructure components of Hongzuizi Bridge located in Changchun was evaluated and sorted. The results were compared with that obtained according to the standards mentioned above， and the effectiveness of the proposed model was confirmed. References | Related Articles | Metrics

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Effect of Anisotropy on CO2Water Two Phase Fluid Migration—Function Improvement of the TOUGH2 Simulator YANG Yanlin， BU Fanting， WANG Fugang， XU Tianfu 2014, 35 (8):  1211-1215.  DOI: 10.12068/j.issn.1005-3026.2014.08.033 Abstract ( 726 )   HTML   PDF (1270KB) ( 581 )   It’s difficult to deal with the heterogeneous anisotropic geological conditions in TOUGH2 simulator， therefore，a new algorithm， using anisotropic permeability tensor， was coupled in TOUGH2 simulator. And the direction of rock’s hydraulic conductivity and elements connection parameters for anisotropic medium was added in the TOUGH2’s input file， which can solve the problems of the anisotropic permeability in different regions and the disparity between the main direction of permeability and the axis direction. Through the simulation of the anisotropic media’s influence on the spatial distribution of CO2 gas saturation， it can be found that CO2 migrates faster and further in the principal direction than the other directions， thereby the effectiveness of the algorithm is proved. The study effectively enhances the function of the TOUGH2’s simulator， which can deal with the seepage problems of complex geological conditions and make the simulation result more objective and practical. References | Related Articles | Metrics