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15 April 2015, Volume 36 Issue 4 Previous Issue    Next Issue
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Information & Control

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Reliable Control for Discrete-Time Markovian Jump Systems with Partly Unknown Transition Probabilities WANG Jian-hua， ZHANG Qing-ling， PANG Bo 2015, 36 (4):  457-461.  DOI: 10.12068/j.issn.1005-3026.2015.04.001 Abstract ( 569 )   HTML   PDF (306KB) ( 913 )   Due to the actuator failures and partly unknown transition probabilities， reliable control problem was studied for a class of discrete linear Markovian jump systems. A reliable controller based on the state feedback method was designed to make the closed-loop systems randomly stable not only when all actuators are operational， but also in case of some actuator failures. The solvability condition of controllers could be equivalent to a feasibility problem of coupled linear matrix inequalities(LMIs). A numerical example demonstrated the feasibility and effectiveness of the proposed design. References | Related Articles | Metrics

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Gas Sensing System Based on Correlation Spectroscopy and Differential Technology ZHANG Ya-nan， ZHAO Yong， WANG Qi， HU Hai-feng 2015, 36 (4):  461-464.  DOI: 10.12068/j.issn.1005-3026.2015.04.002 Abstract ( 701 )   HTML   PDF (504KB) ( 816 )   Based on correlation spectroscopy and differential technology， a novel optical fiber gas sensing system was designed to realize high-sensitive， high-precision and real-time online detection of the trace gas. The theoretical basic of the system was analyzed in detail， and then appropriate devices for the sensing system were selected. Based on this， an optical fiber gas sensing system was constructed to measure the volume fraction of acetylene gas. The proposed system could not only eliminate the disturbances of light-intensity fluctuation and the contaminating gas in the measuring gas， but also avoid the influence of noise and ambient light in the surrounding environment. The experimental results showed that the system resolution could reach 0.5‰， the measurement sensitivity was 6.62μV， the maximum absolue error was 0.15‰， the relative error was 7.5%， the system stability was 2.27%， and the system repeatability error was 0.817%. References | Related Articles | Metrics

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Pedestrian Detection Based on Nonlocal Sparse Feature PENG Yi-shu， YAN Yun-hui， ZHAO Jiu-liang， ZHANG Yao 2015, 36 (4):  465-468.  DOI: 10.12068/j.issn.1005-3026.2015.04.003 Abstract ( 572 )   HTML   PDF (722KB) ( 835 )   By using the constraints around the neighborhoods for weighted sparse representation， the pedestrian detection problem was solved. A dictionary with a strong extracting discriminate and sparse features power was obtained by using the Fisher discriminant dictionary learning method. With the constraint of the neighborhoods， the image patch was represented as a sparse feature via the dictionary. By computing the representation of the residuals and comparing the residuals with a threshold， the patch label was determined to finish the classification task. The experiments on INRIA person datasets showed that non-local sparse feature has an obvious power of discrimination. The constraint of the neighborhoods makes the sparse feature represented effectively. References | Related Articles | Metrics

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Composite Service Reselection Method of Correlation-Aware ZHANG Yue-song， ZHANG Bin， ZHANG Chang-sheng， ZHANG Ming-wei 2015, 36 (4):  469-473.  DOI: 10.12068/j.issn.1005-3026.2015.04.004 Abstract ( 589 )   HTML   PDF (433KB) ( 826 )   Most of the existing researches for composite service reselection method are based on the assumption that the tasks involved are independent. However， in practical scenarios， the QoS of some candidate services have correlations with other services， which leads to the reselected results not to be the optimal one in the real executing environment for these existing reselection methods. To solve this problem， a QoS model supporting the correlations between services was given by extending the OWL-S framework. Based on the proposed model， a composite service reselection method considering the correlations among tasks was provided， in which the correlated tasks were regarded as a task unit and the correlated services of each task unit were regarded as its candidate service set. Experimental results showed that compared with the reselection methods considering the tasks independent， the proposed approach could effectively improve the quality of composite service reselected. References | Related Articles | Metrics

Materials & Metallurgy

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Hydraulic Pressure Control Method in Rear Ultra-Fast Cooling System of Baotou CSP Production Line SHI Jian-hui， YUAN Guo， ZHANG Yong， WANG Guo-dong 2015, 36 (4):  474-478.  DOI: 10.12068/j.issn.1005-3026.2015.04.005 Abstract ( 716 )   HTML   PDF (674KB) ( 840 )   In order to ensure stable production and uniform microstructure of hot-rolled dual phase in CSP rear ultra-fast cooling (UFC)， the high-precision control of the cooling water pressure should be achieved in strip production process. For the problem of the pressure fluctuation in the cooling process of strip， the methods which united power pump closed-loop control and valve fuzzy control， and interlocked power pump closed-loop control and valve closed-loop control were designed by binding technology and equipment features of Baotou CSP rear ultra-fast cooling system. It was found that the head-tail control range of collector pipe pressure is 0.85±0.05MPa， and the middle control range of collector pipe pressure is 0.85±0.01MPa in the actual application. The high-precision control of the cooling water pressure is achieved in low-cost hot-rolled dual phase cooling process of the rear UFC system， and it satisfies the production requirement of hot-rolled dual-phase steel. References | Related Articles | Metrics

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Continuous Cooling Transformation of Corrosion Resistant Steel for Cargo Oil Tank YU Chi， GAO Xiu-hua， WANG Ping， NIU Xi-xi 2015, 36 (4):  479-483.  DOI: 10.12068/j.issn.1005-3026.2015.04.006 Abstract ( 677 )   HTML   PDF (1119KB) ( 903 )   The continuous cooling transformation (CCT) curve of cargo oil tank (COT) steel was obtained by using dilatometric method combined with metallographic analysis-hardness measurement， and the austenites before and after the compress deformation were analyzed， which were tested on MMS-300 thermal mechanical simulation under different cooling rates. The results showed that the dynamic CCT curve compared to static CCT curve obviously moves to the left and up direction， and the starting temperature of austenite increases. With increasing the cooling rate， the microstructures gradually change from polygonal ferrite， pearlite and a little bainite to a small amount of acicular ferrite and granular bainite， finally transform into bainite and martensite. References | Related Articles | Metrics

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Thermodynamic Analysis of Boron Nitride Formation in Boron Microalloyed Steel KIM Kwang-su， DU Lin-xiu， GAO Cai-ru 2015, 36 (4):  483-488.  DOI: 10.12068/j.issn.1005-3026.2015.04.007 Abstract ( 770 )   HTML   PDF (403KB) ( 1278 )   In aluminum killed boron steel， Ti-B steel and Nb-V-B microalloyed steel， the precipitation relation and the precipitate content of the various precipitates， and the influence of those on the solid solution boron content were thermodynamically analyzed by using the solid solubility formula of alloy elements in austenite. The results showed that the precipitation of BN is prior to the precipitation of AlN， so the effective boron content to increase the stability of austenite decreases in the aluminum killed boron steel. The addition of Ti is an effective method of increasing the solute boron content in the boron steel， because the bonding force between Ti and N is stronger than that between B and N. The contents of Nb and V have little influence on the solute B content in microalloyed steel， but the solute boron content only is related to Ti content added in the steel， and Ti content is 3.4~3.8 times of N content in the Ti-Nb-V-B microalloyed steel at least. References | Related Articles | Metrics

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Numerical Simulation of Twin-Roll Casting Magnesium Alloy Strip Process HUANG Feng， DI Hong-shuang 2015, 36 (4):  489-493.  DOI: 10.12068/j.issn.1005-3026.2015.04.008 Abstract ( 571 )   HTML   PDF (493KB) ( 865 )   Based on the characteristics of vertical type twin-roll casting process， the finite element method was used to analyze the three-dimensional steady conservation equations for transport phenomena in the pool region of the twin-roll strip casting for the magnesium alloy.The smart-sizing algorithm of ANSYS software was used to divide finite element mesh， and the coupled simulations of temperature field， velocity field and the solidification process in the molten pool were performed. The effects of main control parameters， such as the casting speed， pouring temperature on the flow field， temperature field and the final point of solidification in the molten pool， were analyzed. The results showed that with the increase of the pouring temperature and the casting speed， the temperature at the exit of the molten pool increases and the final point of solidification moves toward the exit. On the basis of the simulation results， the optimized process parameters of twin-roll casting process for Mg alloy are also given as: the pouring temperature is in 640~660℃ and the casting speed is in 20~30m/min. References | Related Articles | Metrics

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Solidification Nucleation Model Based on Small Wetting Angle Under Pulsed Magnetic Field CHEN Guo-jun， ZHANG Yong-jie， YANG Yuan-sheng， HE Ji-cheng 2015, 36 (4):  493-497.  DOI: 10.12068/j.issn.1005-3026.2015.04.009 Abstract ( 870 )   HTML   PDF (380KB) ( 859 )   Heterogeneous nucleation of small wetting angle under pulsed magnetic field (PMF) was theoretically analyzed on the basis of the Ma nucleation model， with the solidification uncleation model established. The effects of magnetic induction intensity of PMF on the critical nucleation radius and critical undercooling were investigated. The results showed that Gibbs free energy of the model has nothing to do with shape coefficient of heterogeneous nucleation substrate. When the work done by magnetic pressure is the same order as solid-liquid free energy difference under low undercooling， the PMF can effectively reduce the critical uncleation radius， and the effect of the PMF on the critical uncleation radius can be ignored under high undercooling (>20℃). When the substrate size is larger， the undercooling of critical uncleation decreases with increasing magnetic induction intensity of the PMF. References | Related Articles | Metrics

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Effect of Sintering Basic Characteristics on Reduction Degradation Index for Cr-Bearing Vanadium and Titanium Magnetite YANG Song-tao， ZHOU Mi， JIANG Tao， XUE Xiang-xin 2015, 36 (4):  498-502.  DOI: 10.12068/j.issn.1005-3026.2015.04.010 Abstract ( 796 )   HTML   PDF (369KB) ( 810 )   The content of binding phase in Cr-bearing vanadium and titanium magnetite is insufficient， which makes the sintering strength and low temperature reduction degradation index (RDI) bad. The sintering basic characteristics， i.e.， crystal intensity， self-intensity of adhere phase， fluidity of liquid phase， assimilation temperature， were studied in four kinds of Cr-bearing vanadium and titanium magnetites， which were compared with the single burning test results of four kinds of iron ore concentrate， to explore the effect of the sintering basic characteristics on RDI+3.15. The results showed that the RDI+3.15 of sinter decreases with increasing the assimilation temperature， and increases with increasing the strength of binding phase， but the fluidity of liquid phase and crystal intensity have little influence on it. References | Related Articles | Metrics

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Micro-segregation of Solutes in Tin-Containing Ferritic Stainless Steel LI Yang， HAN Ji-peng， JIANG Zhou-hua， HE Pan 2015, 36 (4):  502-507.  DOI: 10.12068/j.issn.1005-3026.2015.04.011 Abstract ( 798 )   HTML   PDF (610KB) ( 995 )   Combined a micro-segregation model with Thermao-calc software， the segregation condition of tin-containing ferritic stainless steel was studied in which the precipitation of MnS was considered. The effects of C， Mn， S， P， and Cr on the interdendritic segregation， zero strength temperature (ZST)， and zero ductility temperature (ZDT) of steel were discussed. The segregation of tin in ferritic steel and low-carbon steel was analyzed， the plastic trough phenomenon in the hot-working process of low-carbon steel was explained and the improvement of plasticity by adding tin was studied. The results showed that the segregation ratio of Sn is much higher than that of other elements except for P and S， and Mn restrains the solidification segregation of S. Tin trends to segregate to grain boundary and the segregation ratio of tin in austenite is much higher than that in ferrite. References | Related Articles | Metrics

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Application of DMF Ore for Sintering of Cr-Bearing Vanadium and Titanium Magnetite ZHOU Mi， YANG Song-tao， JIANG Tao， XUE Xiang-xin 2015, 36 (4):  508-512.  DOI: 10.12068/j.issn.1005-3026.2015.04.012 Abstract ( 692 )   HTML   PDF (362KB) ( 1106 )   Low grade and cheap hematite ore (DMF) was researched for sintering of Cr-bearing vanadium and titanium magnetite (V-Ti-Cr) via sessile drop measuring setup， miniature sintering setup and sintering pot tests. The results showed that DMF has a good fluidity with a wide melting range， a long melting time， and the beginning and ending temperature that liquid generated are low along with a small value of security liquid velocity (0.125mm/min). Therefore， DMF can be used as a matching ore in V-Ti-Cr mixture to make up the disadvantage that V-Ti-Cr sinter owns an insufficient liquid content. Sinter pot tests showed that the optimal additive ratio of DMF is 10%， which is helpful to stabilize the blast furnace operation. References | Related Articles | Metrics

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Effect of PbS on Microstructure of High Lead Tin-Bronze Alloy by Centrifugal Casting LIU Yue， CHEN Chao， QI Zhan-jun， LYU Wen-ling 2015, 36 (4):  512-516.  DOI: 10.12068/j.issn.1005-3026.2015.04.013 Abstract ( 993 )   HTML   PDF (922KB) ( 961 )   High lead tin-bronze alloy was produced by centrifugal casting method. The effects of PbS on microstructure and hardness of high lead tin-bronze alloy were studied. The results showed that in the alloy without PbS addition， the segregation of lead is serious， and the morphology is blocky or stripped. In the alloy with PbS addition， the compounds Cu2S are formed and distributed uniformly on grain boundaries， which are nucleation sites. The compounds Cu2S increase incessantly and form reticular structure， which hinder the segregation of lead. With increasing the mass fraction of PbS， the segregation of lead is reduced， the grains are refined gradually and the hardness increases. The segregation of lead is the smallest， the distribution of lead is the most homogenous and the grains are refined when 3.0% PbS is added. References | Related Articles | Metrics

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Reaction Behavior of Anatase Titanium Oxide in High Calcium System WANG Yan-xiu， ZHANG Ting-an， ZHU Xiao-feng， ZHANG Guo-quan 2015, 36 (4):  517-521.  DOI: 10.12068/j.issn.1005-3026.2015.04.014 Abstract ( 787 )   HTML   PDF (396KB) ( 837 )   Thermodynamic and kinetics analysis of anatase TiO2 reaction in high calcium system were conducted and the possible reactions were determined. Activation energy， reaction order and reaction control types of important reactions were determined by calculation in this system. The reaction behaviors of anatase TiO2 in TiO2-CaO-NaAlO2 system were investigated through experiments. The results showed that when the molar ratio of TiO2 and CaO is 1， the reaction time is 1h， the mass concentration of Na2O is 220g/L， the molar ratio of Na2O and Al2O3 is 3.1， TiO2 reacts with NaOH to produce Na2TiO3 first， then Ca(OH)2 and NaAl(OH)4 react to produce 3CaO·Al2O3·6H2O with increasing temperature. The resultant 3CaO·Al2O3·6H2O reacts with Na2TiO3 to get stable CaTiO3. Anatase TiO2 converts to CaTiO3 completely at 220℃. In this process， elevating temperature can promote the conversion of anatase to the final phase of CaTiO3. References | Related Articles | Metrics

Mechanical Engineering

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Thermal-Structure Coupling Characteristics of Brake’s Rotating Joint Surface LI Xiao-peng， SUN De-hua， LIANG You-jian， ZHAO Guang-hui 2015, 36 (4):  521-526.  DOI: 10.12068/j.issn.1005-3026.2015.04.015 Abstract ( 816 )   HTML   PDF (767KB) ( 733 )   In order to explore the frictional heat and the heat distribution between brake disc and friction plate， the process of emergency braking was simulated using the finite element software. The distribution and variation characteristics of temperature field and stress field were studied. The results showed that the distribution of temperature field and stress field is uneven during the braking process. Their gradients in radial and axial directions are greater， but in circumferential direction is relatively smaller. The thermal and mechanical stress will lead to thermal deformation of the brake disc， which can change contact state and pressure distribution. The change of contact pressure will affect the friction heat input. The thermal deformation of the brake disc is not only the coupling result of the temperature and stress fields， but also the coupling result of the vibration and friction. References | Related Articles | Metrics

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Application of Data Mining Technology in Fault Diagnosis of Tunnel Boring Machine ZHANG Tian-rui， YU Tian-biao， ZHAO Hai-feng， WANG Wan-shan 2015, 36 (4):  527-532.  DOI: 10.12068/j.issn.1005-3026.2015.04.016 Abstract ( 564 )   HTML   PDF (398KB) ( 832 )   Complex fault mechanism and operation parameters of the tunnel boring machine (TBM) were analyzed， and the method of rough set and decision tree algorithm applying to data mining was studied. Take several MATLAB 7.0 dispersed data of tunnel boring machine cutter head as an example， the redundancy attribute of fault samples was reduced by the combination with the rough set attribute reduction algorithm. The rules were extracted with the decision-making tree algorithm. The C4.5 algorithm and the improved C4.5 algorithm were implemented with the data mining tool Clementine， with the results compared. The data was tested by the VB programming. The results showed that the fusion algorithm is a rapid， effective and reliable approach for fault detection and diagnosis. References | Related Articles | Metrics

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Control Strategy Based on Automatic Transmission for Hybrid Loader ZHANG Zhi-wen， ZHAO Ding-xuan， LI Tian-yu， ZHANG Min 2015, 36 (4):  532-536.  DOI: 10.12068/j.issn.1005-3026.2015.04.017 Abstract ( 602 )   HTML   PDF (607KB) ( 857 )   According to the analysis on the working condition characteristics of a 5 tons loader， a parallel hybrid solution based on automatic transmission was proposed for improvement of energy efficiency and torque transmission. The torque and speed online was estimated by fuzzy logic control strategy. We set torque requirement， SOC value of the super capacitor， vehicle speed， accelerator-pedal position and efficiency of hydraulic torque converter as inputs， and the operating point of the engine and the motor and gear of the system as outputs. The results showed that the engine efficiency is improved， the SOC value of the super capacitor is stable， and the gear change is rational and efficient. The hybrid loader saves about 9.56% fuel than that of the conventional one. Meanwhile， the hybrid loader of automatic transmission saves about 11.82% fuel than that of the conventional one， therefore this strategy can improve the fuel economy. References | Related Articles | Metrics

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Internal Flow Field of Flow-Through Air Lint Cleaner Based on CFD DONG Quan-cheng， FENG Xian-ying， ZHANG Cheng-liang 2015, 36 (4):  537-541.  DOI: 10.12068/j.issn.1005-3026.2015.04.018 Abstract ( 664 )   HTML   PDF (485KB) ( 1187 )   The effects of inlet airflow velocity and notch width on the velocity field and lint cleaner pressure field were simulated using the CFD (computational fluid dynamics). The velocity vector was applied to analyze the effect of inlet airflow velocity. The lint cleaner can run normally with velocity of 15m/s， which is easy blocked at higher and lower velocity. The pressure field contour and pressure distribution analysis were used to study the effect of notch width. Under 20mm notch width and 15m/s inlet airflow， no exhaust air phenomenon in lint cleaner while it has the lowest supplement air velocity， the best cleaning rate and loss lint rate. The CFD simulation results are consist to that of the experiment， indicating that the CFD analysis can optimize the operating parameters for the flow-through air lint cleaner. References | Related Articles | Metrics

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Dynamic Similarity Design Method of Distortion Experimental Model for Multiaxial Rotor System LUO Zhong， SHI Hai-li， CHEN Xiao-bing， YU Qing-wen 2015, 36 (4):  542-546.  DOI: 10.12068/j.issn.1005-3026.2015.04.019 Abstract ( 589 )   HTML   PDF (351KB) ( 830 )   A dynamics similarity design method of distortion experimental model for multiaxial rotor-bearing system was proposed on the basis of the Riccati transfer matrix method and the critical speed sensitivity of system parameters.The prototype system spindle was simplified into distortion model upon the sensitivity， then the distortion model was revised and designed into dynamics similarity scaled model. Taking air compressor high-pressure rotor as an example， the critical speed and the inherent characteristics were calculated upon the Riccati transfer matrix method. By comparing the characteristics of the prototype with that of the scaled model， the validity and practicability of the proposed method were verified. References | Related Articles | Metrics

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Natural Characteristics and Sensitivity of TBM Cutterhead System with Multi-degree-of-freedom Coupling LING Jing-xiu， SUN Wei， HUO Jun-zhou， DENG Li-ying 2015, 36 (4):  546-550.  DOI: 10.12068/j.issn.1005-3026.2015.04.020 Abstract ( 762 )   HTML   PDF (556KB) ( 910 )   A multi-degree-of-freedom coupling dynamic model with translation-rotation-bending directions of a TBM cutterhead system was established with considering time-varying meshing stiffness， bearing stiffness， transmission errors and damping， etc. Based on parameters of an actual project， the natural frequencies and corresponding vibration modes were calculated. The influence of natural frequencies and sensitivities with respect to system parameters were investigated. The results showed that the low natural frequencies are 57 and 61Hz， respectively. The natural vibration modes are pinions-motors rotational mode and translational-overturning coupled mode of cutterhead with inner ring gear correspondingly. Meanwhile， the sensitive range of tangential stiffness about cutterhead pieces is 3~4GN/m and the mass sensitive range is 19~23t， respectively. References | Related Articles | Metrics

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Resistance Characteristics of Hydraulic Excavator REN Zhi-gui， CHEN Jin， WANG Shu-chun， PANG Xiao-ping 2015, 36 (4):  551-556.  DOI: 10.12068/j.issn.1005-3026.2015.04.021 Abstract ( 781 )   HTML   PDF (496KB) ( 924 )   Based on three kinds of conventional digging patterns， the variation regularities of digging resistance with time and digging trajectory in a single digging process were studied. The characteristics of the resistance coefficient and the resistance moment coefficient in different stages of the digging process were obtained， which were based on the comparison of multiple experimental results. Based on the variation regularities of direction angles， the impact of each component motion on digging resistance direction was investigated. The distribution characteristics， the main value range and the probability density of the resistance coefficient， the resistance moment coefficient， the resistance angle and the difference angle in different value range of digging resistance were calculated on the basis of the statistical theory. The results lay a foundation for calculation of theoretical digging force and design and optimization of device. References | Related Articles | Metrics

Resources & Civil Engineering

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Experimental Analysis of Wedges Sliding and Its Discriminant Method WANG Shu-hong， ZHONG Shan， GAO Xuan-lin， WANG Yi-ran 2015, 36 (4):  557-560.  DOI: 10.12068/j.issn.1005-3026.2015.04.022 Abstract ( 613 )   HTML   PDF (534KB) ( 882 )   A self-developed test platform was used to conduct a large number of rock wedge sliding experiments， based on which a distinguishing criterion of limit equilibrium state to judge whether the wedges slide or not was put forward. The wedges sliding process and its limit equilibrium state were studied to get the beta-alpha equation (relation between inclination and rotation angle) under different condition. The effects of rock structural plane parameters (occurrence， roughness coefficient JRC) on the correlation coefficient of the proposed function equation were quantitatively analyzed， with the beta-alpha equation given by using the known slider roughness coefficient JRC and structural plane angle ω. References | Related Articles | Metrics

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Caving Space Optimization Experiment on Middle-Deep Hole Blasting for Steeply Inclined Thin Veins AN Long， WU Jin， XU Shuai， LI Yuan-hui 2015, 36 (4):  560-564.  DOI: 10.12068/j.issn.1005-3026.2015.04.023 Abstract ( 680 )   HTML   PDF (553KB) ( 971 )   Taking the 18# thin vein of Jinchanggouliang Gold Mine for example， the similar material simulation experiment face-end drawing was conducted under the restraint of the inclined side walls. At the height of 12 and 14m and inclining to the side walls， the widths of the spheroid were measured as 1.7 and 2.1m， respectively， under the flow axial angle of 4°. Thus， the scopes of caving space were determined as 1， 2 and 3m， respectively. Under the optimum experiment between the recovery rate and the dilution rate， the optimum space was determined to be 1m under the height of 12 and 14m. The industrial test at the blasting test area under the space of 1m was accomplished when the 3D laser scanning CMS system was used to scan the tested areas. The results showed that a sound blasting effect was achieved with most part of the bulk ore rocks drawn， the top wall rocks remaining integrated， and the bottom side wall only partially under excavated. References | Related Articles | Metrics

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Triangle Meshes Model for Extracting Profile Contour of Goaf and Its Application LUO Zhou-quan， ZHANG Wen-fen ， XU Shi-min 2015, 36 (4):  565-570.  DOI: 10.12068/j.issn.1005-3026.2015.04.024 Abstract ( 745 )   HTML   PDF (567KB) ( 782 )   Based on analysis on defects of the triangular meshes currently used for sectional contour extraction applied to the goaf， the conventional sectional contour extraction method was improved and a new method called convex hull penetration method was formed to extract the sectional contour line of goaf with complex boundary. First， the convex hull line of unordered point set in the plane vertical to arbitrary axis was obtained by cutting triangular mesh model of goaf， then a complete cross-section contour line was got by putting the points of the initial contour line following the principle of maximum opening angle into the contour line， in order to form the profile of goaf. The practical application showed that the proposed method could extract the profile’s contour line of complex quickly and effectively， acquire accurately profile contour of goaf， analyze comparatively over excavation and under-excavation amount， which has the very good practical value. References | Related Articles | Metrics

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Optimization of Transition Zone Thickness and Numerical Analysis for Deep Hard-Rock Mining LIU Dun-wen， CHU Fu-jiao， REN Gao-feng， WU Di 2015, 36 (4):  571-575.  DOI: 10.12068/j.issn.1005-3026.2015.04.025 Abstract ( 695 )   HTML   PDF (738KB) ( 805 )   Aiming at the ground control problem during underground stoping at deep iron mine， some reasonable stope parameters were chosen and optimized. In consideration of weak intercalated layer would influence the stability of transition zone， 3 kinds of alternative thickness of the transition zone which were 8.5， 10 and 12m were selected by using limit equilibrium method. Besides， three-dimensional numerical model was established with the large-scale numerical analysis software FLAC 3D， which was used to make a comparative analysis of its stability. Numerical results showed that the stress concentration during the process of mining becomes less obvious and the displacement of roof decreases with the increasing thickness of transition zone， and the plastic zone at only 12m thickness of transition zone has not been connected. It follows that 12m transition zone can guarantee stope stability， and satisfy safety production requirements during the transition period， which provides basis for the safe production of mine transition. References | Related Articles | Metrics

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Stresses and Deformations in Pile-Anchor Support System of Deep Foundation Pit in Sandy Layers ZHAO Wen， HAN Jian-yong， LI Shen-gang， GUAN Yong-ping 2015, 36 (4):  576-581.  DOI: 10.12068/j.issn.1005-3026.2015.04.026 Abstract ( 840 )   HTML   PDF (663KB) ( 1376 )   Based on the long-term monitoring data of the foundation pit of Golden City Square project in Shenyang， the horizontal displacements and deformations on the pile top and in the pile body， as well as the prestress in the anchors were analyzed in order to understand the mechanical characteristics and deformation laws in the pile-anchor support system. Results showed that time effect of deformation in the support system of the foundation pit is not significant in sandy layer. However the spatial effect of the horizontal displacements on the pile top is significant. The horizontal displacements of the pile body take on a fish belly shape with small values at the two ends and large values in the middle. Due to the effect of the prestress in the anchor， the deformation curve of the pile body is similar to that of a simply supported beam. Anchors are significantly affected by seasonal frost heavy， whose influence is gradually reduced from top to bottom. The 600mm diameter supporting piles in the pile-anchor support system are capable of controlling the deformation， thus being feasible in this project and having a broad application prospect. References | Related Articles | Metrics

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Mineralogical Study of Boron-Bearing Iron Concentrate Ore GAO Peng， YU Jian-wen， HAN Yue-xin， ZHOU Man-geng 2015, 36 (4):  581-584.  DOI: 10.12068/j.issn.1005-3026.2015.04.027 Abstract ( 735 )   HTML   PDF (551KB) ( 945 )   The chemical composition， mineral composition， dissemination characteristics of the minerals were detailedly investigated by traditional process mineralogy method and XRD， MLA automatic detection，chemical analysis， etc. The results showed that boron and iron respectively occur in the main form of szaibelyite and magnetite， and the primary gangue minerals are serpentine， mica and carbonate minerals. Crystal stock of minerals is complex and intergrowth ralation of minerals is close， the magnetite， szaibelyite and ludwigite are closely symbiotic， they are usually associated with serpentine， and mica closely in the shape of sawtooth or irregular. The results may provide the basis for the rational comprehensive utilization of the boron-bearing iron concentrate. References | Related Articles | Metrics

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Effects of Calcium Oxide on Sintering-Separation of High Iron-Bearing Bauxite YUAN Zhi-tao， FANG Ping， ZHANG Song， LI Li-xia 2015, 36 (4):  585-589.  DOI: 10.12068/j.issn.1005-3026.2015.04.028 Abstract ( 818 )   HTML   PDF (511KB) ( 1290 )   Reduction sintering - magnetic separation process was adopted to deal with high iron-bearing bauxite. The effects of calcium oxide on sintering and Al-Fe separation effect of sintering product were analyzed. Components and microstructure of the reduced sintering product added different dosage of calcium oxide were studied by X-ray diffraction and scanning electron microscope. The results showed that metallization rate of sintering product reached 93.95%， the mass fraction of Fe in the magnetic concentrate was 83.10% and Al2O3 leaching rate of rich aluminum slag increased to 61.14% when the mass fraction of calcium oxide is 70%. CaO could completely react with Al2O3 and SiO2 to produce 12CaO·7Al2O3 and Ca2SiO2， respectively， while Fe element was well reduced to iron which can be well separated from non-ferrous gangues by the magnetic separation. References | Related Articles | Metrics

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Geochemical Characteristics and Tectonic Setting of Hannuoba Basalts from Pingzhuang—Yuanbaoshan Basin in Chifeng PENG Yan-dong， HUANG Fei， XING De-he， ZHANG Zhi-bin 2015, 36 (4):  590-595.  DOI: 10.12068/j.issn.1005-3026.2015.04.029 Abstract ( 951 )   HTML   PDF (414KB) ( 1269 )   Petrology， geochemistry characteristics of the Hannuoba basalts distributed in Pingzhuang—Yuanbaoshan basin in eastern of Chifeng， Inner Mongolia were studied. The results showed that the volcanic rocks are dominated by basalts and minor sedimentary tuff. The petrologic compositions of basalts are homogeneous， content of the main elements change rarely， the basalts is characterized by higher titanium， lower aluminum and high Na2O content，lower K2O content. The total amounts of REE are lower， LREE is enriched， and there are weak Eu and weak Ce negative anomaly for Hannuoba basalts. The basalts are obviously enriched inlithophile elements (Rb，Ba，Th，K，Ta， LREE etc.)， and depleted in high field-strength element(U，HREE)as well as compatible elements (Co， Ni， Cr etc.). The Hannuoba basalts belong to the tholeiitic basalt series， and the source region of volcano rock is the asthenospheric upper mantle.The Hannuoba basalt formed in a continental rift tensile environment which is the product of continental intraplate stable tectonic environment. References | Related Articles | Metrics

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Mechanism of Adsorption and Aggregation of Fine Siderite，Quartz and Hematite ZHAO Rui-chao， HAN Yue-xin，YANG Guang， LI Yan-jun 2015, 36 (4):  596-600.  DOI: 10.12068/j.issn.1005-3026.2015.04.030 Abstract ( 842 )   HTML   PDF (433KB) ( 1035 )   In the grinding process of refractory iron ore containing siderite， the siderite is very easy to be slimed. A large number of fine siderite particles were adsorbed on the surface of gangue and useful minerals， which seriously deteriorates the following processing. In order to find out the essence and rules of adsorption and aggregation among the fine siderite，quartz and hematite in pulp， DLVO theory was applied to study the interaction mechanism between the fine siderite particle and the coarse quartz particle ， the fine siderite particle and hematite particle， the fine siderite particles，etc. The calculating results showed that the fine siderite particles are easily adsorbed on the surface of coarse quartz particles and hematite particles. The agglomeration phenomenon occurs between fine siderite particles and fine hematite particles， and doesn′t occur between the fine siderite particles. References | Related Articles | Metrics

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Lot-Size Policies in 3-Stage Production-Distribution System Based on Performance Contrast TANG Jin-huan， JI Shou-feng， ZHU Bao-lin 2015, 36 (4):  601-605.  DOI: 10.12068/j.issn.1005-3026.2015.04.031 Abstract ( 621 )   HTML   PDF (436KB) ( 759 )   Aiming at the 3-stage production-distribution system composed of producers， regional distribution centers (RDC) and distributor， the RDC lot-sizing policy was studied. First， the great common divisor (GCD) was taken as an adapted time base to optimize the production- distribution system model， and then the stationary policy was obtained. Different scenes in production-distribution process were discussed to obtain the multiple lot-sizing policies. The performance contrast standard was introduced to uncover the stationary lot-sizing model and the multiple lot-sizing model. The numerical experiments were conducted with the data from the Northeastern Chemical Sales Company of the PetroChina. The results confirm the validity of the standard and the model. References | Related Articles | Metrics

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New Reordering Method for Comprehensive Evaluation and Solving Algorithm LI Wei-wei， YI Ping-tao， GUO Ya-jun 2015, 36 (4):  605-608.  DOI: 10.12068/j.issn.1005-3026.2015.04.032 Abstract ( 851 )   HTML   PDF (299KB) ( 1176 )   Aimed at expanding the evaluation conclusion of the absolute form for classic evaluation result， a kind of possibility sort conclusion was developed. The superior degree matrix used for advantage comparison among objects was introduced. The notion and definition of possibility sort conclusion were discussed upon the superior degree matrix. A solving algorithm of the conclusion was proposed using stochastic simulation to increase the stability of conclusion. This conclusion gives rank with the probability， which may provide explanation for uncertain evaluation problems. References | Related Articles | Metrics