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Table of Content

    25 September 2012, Volume 40 Issue 9
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    Chemistry & Chemical Engineering
    Pyrolysis Characteristics of Eucalyptus APMP Spent Liquor Solids
    Wu Shu-bin Zhao Yu-shuang Guo Da-liang Li Bo Yin Xiu-li
    2012, 40(9):  1-7. 
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    The APMP ( Alkaline Peroxide Mechanical Pulp) spent liquor solid ( ASLS) of Eucalyptus was prepared and pyrolyzed,and the release mechanism of main volatile products during the pyrolysis was investigated by means of TG-FTIR. Then,the volatile components are confirmed by combining a fast pyrolysis in a high-temperature static horizontal tube furnace with GC and GC-MS. TG-FTIR analysis shows that the pyrolysis of ASLS consists of three stages,respectively at temperatures of 200 ～ 371 ℃,371 ～ 530℃,745 ～ 986 ℃,and the correspon-ding main products are CO2 with a content of more than 90% at the first pyrolysis stage,CO2,CH4,aldehydes and ketones,phenols and alcohols at the second pyrolysis stage and CO at the third pyrolysis stage. GC results indicate that H2,CH4,CO,CO2,C2H4 and C2H6 are the main non-condensible products. GC-MS results reveal that aldehydes and ketones as well as phenols are the main condensible products,which accords well with the TG-FTIR results,and that the maximum yield of aldehydes and ketones is up to 41. 43% at about 600℃.

    Biodiesel Production from Lard Catalyzed by Calcium-Based Solid Base in Ultrasonic Field
    Zou Hua-sheng Lei Min Li Jian
    2012, 40(9):  8-13. 
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    In this investigation,a two-step catalysis process was developed to prepare the biodiesel from the waste lard. First,under the irradiation of 40 kHz ultrasonic,the pre-esterification of the lard with methanol is carried out by using concentrated sulfuric acid as the catalyst. Then,the solid base catalyst CaO/NaA was prepared by means of the isovolumetric impregnation. Finally,the solid base catalyst prepared in optimal conditions was employed to
    catalyze the transesterification of the pre-esterified lard with methanol in a 40 kHz ultrasonic field,thus obtaining the biodiesel. The results show that, for the pre-esterification of lard with an initial acid value of 13. 82mg KOH/g,optimal conditions are a ultrasonic power of 150W,a methanol-to-oil molar ratio of 8: 1,a reaction temperature of 50℃ and a concentrated sulfuric acid dosage of 2. 5%,and under such conditions,the acid value of lard can be
    reduced to 1. 91mg KOH/g in 30min,that the optimal preparation conditions of the solid base catalyst CaO/NaA,which are obtained by the orthogonal experiments,are a CaO loading amount of 15%,a roasting temperature of 700℃ and a roasting time of 6 h; and that the conversion of methyl ester reaches about 95.8% in 120min in optimal preparation conditions of the biodiesel,namely,a ultrasonic power of 150W,a methanol-to-oil molar ratio of 9: 1,a temperature of 55℃ and a solid base catalyst dosage of 4%,and the solid base catalyst is still of high activity after being used three times.

    Synthesis and Water Vapor Adsorption Property of Meso-Porous Adsorbent SiO2-TiO2
    2012, 40(9):  14-19. 
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    First,the meso-porous adsorbent SiO2-TiO2 was synthesized via the sol-gel method. Next,its structure and morphology are characterized by using N2 adsorption and desorption isotherms and by means of TEM so as to reveal the influence of the titanium content in the titanium-doped silica gel on the silica gel structure. Then,the water vapor adsorption and regeneration properties of the adsorbent SiO2-TiO2 are investigated by using a dynamic water vapor sorption analyzer ( DVSA) ,and the desorption activation energy of water molecules on absorbent was also estimated by a temperature programmed desorption ( TPD) test. Finally,the Frenkel-Halsey-Hill ( FHH) model is used to analyze the surface roughness and pore size distribution of the adsorbent. The experimental results show that,with the decrease of the titanium-to-silicon molar ratio,the specific surface area of the adsorbent increases with a narrower pore size distribution and a smaller average pore size,and the desorption activation energy of water molecules on absorbent decreases,and that,the adsorbent SiO2-TiO2 is of a lower regeneration temperature,and its water vapor adsorption capacity is greater than that of MCM-41 silica under a low relative humidity of less than 30%.

    Integration of Low-Temperature Cold Storage and Cryogenic Power Generation System Based on LNG Cold Energy Utilization
    Xiong Yong-qiang Hua Ben
    2012, 40(9):  20-25. 
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    In order to improve the utilization efficiency of LNG cold energy,based on the exergy analysis of the LNG ( Liquefied Natural Gas) cold energy utilization in a low-temperature cold storage and with a binary mixture of a methane-to-ethane mass ratio of 65: 35 as the working fluid,a Rankine cycle utilizing cold energy to generate power is integrated with the refrigeration process of the cold storage utilizing the LNG cold energy so as to not only keep a constant necessary supply of cold energy for the cold storage but also convert the deep cryogenic exergy of LNG in the cold storage to power by the Rankine cycle. Meanwhile,the influences of some parameters of the Rankine cycle on the power generation efficiency are also analyzed. The results show that the proposed integration system not only meets the cold energy requirements of the cold storage but also generates a power of approximately 15. 5 kW·h per ton of LNG,and the exergy efficiency of the LNG cold utilization in the system increases from 38. 5% to 54. 0%.

    Effects of Binder Resins on Expansion and Flame-Retardant Performances of Waterborne Fire-Retardant Coatings
    Fan Fang-qiang Xia Zheng-bin Li Qing-ying Li Zhong Chen Huan-qin
    2012, 40(9):  26-31,37. 
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    In this investigation,the waterborne ultra-thin fire-retardant coatings for steel structures were prepared respectively with the silicone-acrylic, acrylic, styrene-acrylic and VAc-VeoVa latexes as the binder. Then,the effects of the binders on the fire-retardant performance of the coatings were discussed in terms of the thermal stability and the high-temperature rheology. The combustion test results of analoging large panels show that the expansion
    ratio,17.4 times that of the fire-retardant coatings from the VAc-VeoVa latex,is the largest,and its fire-retardant performance is the best with a steel backside temperature of 304℃ after a 30-min combustion. It is seen from TGA curves that the VAc-VeoVa polymer is of good thermal stability and its average thermal degradation rate is the lowest,and that those characteristics of the VAc-VeoVa polymer provide enough time for its reaction with ammonium polyphosphate,thus generating a dense char layer which can remarkably improve the fire-retardant performance of the coating. Moreover, the results of the dynamic rheological test demonstrate that,for the acrylic and styreneacrylic molten polymers,the storage modulus ( G') are higher than the loss modulus ( G″) ,which means that the elastic flow is predominant in these melts,and their complex viscosities are more than 1 000 Pa·s, while for the VAc-VeoVa molten polymer,G″ is higher than G',which means that the viscous flow is predominant in this melt,and its complex viscosity is 33 Pa·s,and that,for the VAc-VeoVa melt,a Newtonian fluid property is displayed at the low frequency stage,and the complex viscosity slightly decreases at the end of the high frequency stage. The above-mentioned results show that the viscous fluid with good thermal stability and low complex viscosity can be used as the binder of fire-retardant coatings,which is helpful in the expansion and fire retardancy of the coatings.

    Simultaneous Determination of Stilbene Glucoside and Five Anthraquinones in Polygonum multiflorum Thunb. by Means of Micellar Electrokinetic Capillary Chromatography
    Wu Hong Wang Yan Wen Peng Lou Wen-yong Zong Min-hua
    2012, 40(9):  32-37. 
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    In this investigation,a method of using the micellar electrokinetic chromatography was laid down for the simultaneous determination of stilbene glucoside and five anthraquinones,including emodin,aloe-emodin,rhein,chrysophanol and physcion,in Polygonum multiflorum Thunb.,and the effects of the buffer solution pH value,the SDS concentration,the sodium tetraborate concentration,the methanol volume fraction and the operating voltage on
    the separation and determination were discussed. The results show that optimal separation and determination conditions are an operating voltage of 25 kV and a buffer solution with a pH value of 9.6,15mmol /L of sodium tetraborate,30mmol /L of SDS and 10%( volume fraction) of methanol,and that, in the optimal conditions,stilbene glucoside and the five anthraquinones are completely separated within 18minutes,with a relative standard deviation of migration times of 1.06% ～ 1.61%,a relative standard deviation of peak areas of 1.46% ～ 2.87%,a detection limit of 0.26 ～ 0.56mg /L and a recovery of 97.2% ～ 103.2%.

    Oxalate Formation Rules During Oxygen Delignification of Kraft Pulp
    Li Hai-long Zhan Huai-yu Chai Xin-sheng Liu Meng-ru Fu Shi-yu
    2012, 40(9):  38-41,68. 
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    In this paper,the effects of the oxygen delignification of southern pine Kraft pulp on the oxalate formation were investigated,and the relationship between the oxalate formation and the Kappa number was also discussed. Then,according to this relationship,a mathematical model was constructed to predict the oxalate content during the oxygen delignification. The results show that the oxalate content gradually increases during the oxygen delignification and increases with the temperature and the alkali dosage,while the oxalate formation is not affected by the oxygen pressure,and that,for the proposed model,the linear correlation coefficient between the predicted value and the measured one is 0. 969,which means that the prediction accuracy is higher,so it can be used to predict the oxalate content in the oxygen delignification effluent of a given pulp.

    Computer Science & Technology
    Hadoop Data Load Balancing Method Based on Dynamic Bandwidth Allocation
    Lin Wei-wei Liu Bo
    2012, 40(9):  42-47. 
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    Data load balancing greatly affects the performance of the Hadoop distributed file system ( HDFS). In order to overcome the inefficiency and inflexibility of the default data load balancing method in HDFS,this paper devises a novel dynamic load balancing method,which dynamically allocates network bandwidth to achieve the data load balancing by controlling variables. Then,the corresponding mathematical model is constructed based on the controlled variables. Experimental results show that the devised method can not only guarantee the performance of the HDFS data access system but also improve the data load balancing efficiency in the presence of a new cluster node.

    Geometrically robust Image content authentication Based on Polar Complex Exponential Transform
    2012, 40(9):  48-55. 
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    In this paper, a geometrically robust image content authentication algorithm based on the Polar Complex Exponential Transform is presented. First of all, the important visual image contents are enhanced by the response values of SUSAN detector, and the PCET moments of the enhanced image are calculated to get the content authentication features. Then with deterministic adaptive quantization the authentication bits are obtained from the quantified authentication features. Finally, the authentication bits are embedded in the PCETs amplitude of the original image with quantization index modulation method. When verifying the image, the watermark extracted from a test image are compared with the the authentication bits of tested image to determine whether the image has been tampered. Experimental results show that this algorithm has the following advantages: it is robust to geometry distortion of rotation and scale; it can resist the processes such as compression, enhance, filter and noise; and it is sensitivity to small tampering.

    Adaptive Dynamic Trust Evaluation Model for P2P Networks
    Feng Yu-xiang Ying Wei-qin
    2012, 40(9):  56-61. 
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    Aiming at the dynamic trust evaluation in large-scale distributed systems,which are similar to peer-topeer file-sharing systems,an adaptive dynamic trust evaluation model is constructed based on the genetic algorithm. In this model,the trust relationship between nodes changes dynamically according to their history behaviors and other evaluation data.  Moreover,this model can automatically generate and update evaluation rules with the changes of network environment. Experimental results show that,as compared with the existing trust evaluation models,the proposed model is of a better dynamic adaptive ability in the presence of the dynamic changes of network environment.

    Generalised Coiteration and Its Calculation Laws
    Su Jin-dian Yu Shan-shan
    2012, 40(9):  62-68. 
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    Due to a lack of general descriptions of various corecursion operations defined on coinductive data types in functional programming,gunfold,a definition of generalised coiteration for coinductive data types,is proposed based on Monads and its distributive laws on coalgebraic functors. It is proved that gunfold can offer a general and abstract description of the coiteration,the primitive corecursion and the course-of-value coiteration. Based on the proof,the properties and the relevant calculation laws for gunfold are analyzed from the viewpoint of the category theory.

    Multi-Label Classification Algorithm Using Adaptive Linear Regression
    Tang Jin Huang Li-li Zhao Hai-feng Luo Bin
    2012, 40(9):  69-74. 
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    Aiming at the co-occurrence and relevance among the multi-label data,a novel multi-label classification algorithm using adaptive linear regression is proposed. In the algorithm,first,the classical linear regression theory is extended to the multi-label linear regression. Then,the threshold for the regression results is set by combining various evaluation criteria,thus adaptively predicting the final labels. The proposed algorithm considers not only the fixed threshold corresponding to the averages but also the adaptive thresholds reflecting the comprehensive effects of the classifier,thus reducing the influence of the distribution and noise of original data on the classification. Experimental results demonstrate that the proposed algorithm is effective in the multi-label classification.

    Somatic Operation Based on Sensor of Android Mobile Devices
    Han Di Pan Zhi-hong
    2012, 40(9):  75-80. 
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    The context awareness based on the ubiquitous computing has been widely used in our life. In order to realize somatic operations by using a well-established sensing technology on Android mobile devices,this paper devises a new somatic operation system based on Android. In this system,the middleware technology is employed to achieve the communication between the server and the Android mobile devices,including the transmission of the effectively-identified data,the pattern recognition of the user operation and the quantization of the load motion data. Meanwhile,the analog data are acquired through the sensor and are then converted into executive digital commands,thus promoting the sensor development of the Android mobile phone. Experimental results show that the proposed system is of higher accuracy and lower energy consumption and is capable of being used in different situations.Key words:

    Electronics, Communication & Automation Technology
    One-Sided SPSA-Based Data-Driven Control Algorithm with Dynamic Deviations
    Ai Wei Zhu Xue-feng
    2012, 40(9):  81-86,92. 
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    Using simultaneous-perturbation stochastic approximation ( SPSA) algorithm to establish a data-driven control method is feasible when the mathematical models of controlled systems are totally unknown. In this paper,the principle and effectiveness of both the SPSA algorithm and its improved algorithms are investigated,and the shortcomings of the SPSA algorithm in the control-oriented situation,such as lower gradient approximation efficiency,are analyzed. Then,a one-sided SPSA algorithm is proposed for the control problem,which saves one-third data
    compared with the SPSA algorithm in the actual control,thus obtaining enough convergence rate and accuracy of the optimization procedure for the control problem. Then,by combining the one-sided SPSA algorithm and the datadriven control method,a data utilization scheme is designed based on dynamic deviations,and the connection weights in a neural network function approximator are adjusted directly and adaptively. Simulatied results show that the proposed data-driven control method secures excellent control over nonlinear systems without the help of any model.

    Modeling of Differentiated Queuing Service Based on FBM Traffic Model
    Guo Mian Jiang Sheng-ming Guan Quan-sheng Mao Hua-chao
    2012, 40(9):  87-92. 
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    Differentiated queuing service ( DQS) is a QoS ( Quality of Service) model that can efficiently provide QoS for wired and wireless integrated networks. In this paper,based on the service discipline of DQS,the arriving flows with the same delay requirement are taken as an FBM ( Fractional Brownian Motion) traffic,and then the DQS models with multi-class FBM traffic and with the corresponding delay requirements are established. Moreover,the formula of the packet loss is deduced according to the proposed models. It is shown that the simulated results of the proposed models are consistent with those obtained based on the packet size. Besides,the analytical results of the model performances also demonstrate that the burstiness of real-time traffic greatly affects the QoS guarantee of DQS.

    Design of Reverse Converter for Four-Moduli Set
    Lü Xiao-lan Yao Ruo-he
    2012, 40(9):  93-96,103. 
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    Aiming at large DR ( dynamic range) residue number systems ( RNS) ,a new four-moduli set{ 2n －1,22n + 1,2n + 1,2n －1} is proposed. Then,a high efficiency and parallel conversion algorithm for the residue-tobinary conversion of the new moduli set is realized based on the new Chinese remainder theorem 1,and the corresponding converter circuit is designed. As compared with the common converters using the same 5n-bit DR moduli set,the proposed converter adopts adders as the primitive operators,so that it greatly reduces the hardware requirement and significantly decreases the area and delay,thus increasing the conversion efficiency.

    Hybrid Swarm Intelligent Algorithm for Multi-Target Data Association
    Yuan De-ping Shi Hao-shan Zheng Juan-yi
    2012, 40(9):  97-103. 
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    In order to rapidly realize the association of multi-target data,a hybrid swarm intelligent algorithm is proposed by combining the ant colony optimization ( ACO) algorithm with the particle swarm optimization ( PSO) algorithm. In the algorithm,first,a combinatorial optimization model for the multi-target data association is constructed by using the tracking gate to confirm the effective measurements of targets and by using the likelihood function of the filter innovation to describe the association relation between the measurements and the targets. Then,the PSO algorithm based on the cross and mutation rules is used to obtain the suboptimal solution to the constructed model,and according to the suboptimal solution,the location and pheromone of each ant are initialized. Finally,the ACO algorithm is employed to make a fine searching in the solutions to target functions,so as to obtain a better solution. Simulated results indicate that the proposed algorithm can effectively improve the accuracy and convergence speed of the data association.

    Fuzzy AHP-Based Multi-Attribute Vertical Handover Algorithm
    Jiang Kai-yuan Gu Xue-mai Guo Qing Ning Lei Chen Li-ming
    2012, 40(9):  104-109,122. 
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    In order to offer the seamless handover between different networks and the continuity guarantee of the traffic for mobile nodes,a multi-attribute vertical handover algorithm ( FAVHO) is proposed based on the fuzzy analytic hierarchy process ( FAHP) . In the algorithm,according to the fuzziness of human mind,fuzzy numbers are adopted to describe the comparison results of the importance of attributes and a fuzzy judgment matrix is established to eliminate the differences in the consistency between the judgment matrix and the human mind in traditional algorithms. For the purpose of improving the handover effectiveness,an adaptive timer is designed in view of the motion state of the mobile node and the load state of the target base station. Simulated results show that the proposed algorithm can improve the handover performance,increase the system throughput and reduce the dropping probability of the system.

    Memory-Based Symmetric Raised-Cosine Keying Modulation Method
    Guo Li-li Zhou Bin Yang Peng Sun Zhi-guo
    2012, 40(9):  110-115. 
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    The phase and frequency of the symmetric raised-cosine keying ( SRCK) modulation signals are continuous,but the bit error rate ( BER) of the SRCK signals is higher than that of the minimum frequency shift keying ( MSK) signals. In order to solve this problem,an improved SRCK modulation method is devised to decrease the BER by adding the memory between the SRCK signals corresponding to symbols. Simulated results show that the signals obtained through the devised modulation method are superior to the MSK signals in terms of the energy concentration and the BER performance,with a gain of 3dB,and that,for the improved SRCK signals,suitable modulation parameters can be determined by calculating the minimum Euclidean distance.

    Combinational Gaussian Background Modeling Method Based on Analysis of Spatio-Temporal Entropy
    Song Jia-sheng Hu Guo-qing
    2012, 40(9):  116-122. 
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    In order to increase the update speed of Gaussian models for the background in video surveillance systems,the concept and computation method of the scene moving complexity are devised,according to which a combinational Gaussian background modeling method is devised. In this method, according to the spatio-temporal model of pixels,the scene moving complexity is analyzed and the entropy image of the scene is calculated. Then,this image is segmented into the stable region and the dynamic region by means of the maximum entropy threshold. In the two different regions,two different Gaussian models and corresponding updating algorithms are respectively adopted. Finally,the devised method is used to implement the foreground segmentation of the video sequences with a size of 384 × 288 pixels. The results show that the devised method is of a greater update speed for the background model and can effectively segment moving objects.

    Performance Analysis of Telerobotic System Based on Event Prediction
    Chen Dan Xi Ning Tang Xu-sheng
    2012, 40(9):  123-130. 
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    The variable time delay and packet loss of Internet significantly degrade the manipulability of Internetbased telerobotic systems and even make the systems unstable. In order to lessen the influence of the variable time delay on the system performance,a single-step time-delay prediction algorithm is proposed based on the sparse multivariate linear regression algorithm of variable sliding windows. Then,a new Internet-based telerobotic system is built up in view of event prediction. In the proposed system,a discrete path governor based on time delay prediction is added at the master site, which generates a suitable event parameter online for predicting the path by solving a look-ahead optimization function,thus improving the tracking performance and environmental adaptability of the proposed system so as to deal with emergent events. Moreover,the stability conditions of the proposed system are also proposed according to the Lyapunov stability theorem. The results of local and trans-regional experiments of a telerobot demonstrate that the proposed methods can effectively solve the stability and performance degradation problems caused by the variable time delay and the packet loss.

    Architecture & Civil Engineering
    Judgement Characteristics and Quantitative Index of Suitable Block Scale
    Huang Ye-qing Sun Yi-min
    2012, 40(9):  131-138. 
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    By analyzing the connotation of blocks,the judgement characteristics of a suitable block scale are summed up and are used to perform a quantitative research on the suitable block scale. Then,according to the statistical data and the contrast analysis of the block scales of ninety urban central districts abroad,a quantitative index of suitable block scale is determined. The results show that,in urban design,the reasonable block scale should
    be controlled at less than 200m; and that,as the block scale in Chinese cities tends to become larger,a more suitable scale should be set within the range of 150 ～ 200m. The presented quantitative index can be used as a general criterion for the judgement of optimal block scale and it provides a reference for determining suitable block scale in urban design.

    Effect of Unsymmetrical Form of Gymnasium on Wind Environment of Spectator Area
    2012, 40(9):  139-144,159. 
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    In order to increase the indoor air change rate of gymnasiums and enlarge the thermal comfort zone of the spectator area under natural ventilation condition and with special consideration of the environment in Guangzhou,China,the symmetrical and unsymmetrical form models of a gymnasium are simulated with Fluent and Weather Tool. The results indicate that,in the same external condition,the unsymmetrical form is more effective in increasing the indoor air change rate of the gymnasium than the symmetrical form,and that,by adjusting the relative position between the wind direction and the windward side,the thermal comfort zone of the spectator area of the gymnasium in an unsymmetrical form can be enlarged under natural ventilation condition,thus increasing the use efficiency of natural resources in hot and humid regions.

    Influence of GFRP Bars on Mechanical Behaviours of Concrete Slabs with Arching Action
    Li Chun-hong Wei De-min Zheng Yu
    2012, 40(9):  145-152. 
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    Due to the restraint from the components aside concrete slabs,arching action occurs in these slabs. In order to reveal the influences of glass fibre reinforced polymer ( GFRP) bars on the concrete slabs,ten slabs were loaded until failure. The results show that the arching action gradually become significant after the occurrence of cracking in the slabs,and that,the role of GFRP bars in the tensile area is like that of the springs connecting with
    two arch legs,that is,with the increase of the stiffness of the equivalent springs for reinforcement,the arching action weakens,otherwise the arching action is enhanced. Furthermore,it is found that too low reinforcement percentage in the slabs or locating reinforcement at the mid-depth of the slabs is unprofitable to the control of both the deflection and the cracking width,while appropriate reinforcement percentage makes the GFPR bars and the arching action jointly play their roles,which can narrow the gap in the serviceability between the slab with an appropriate reinforcement percentage and that with a higher reinforcement percentage,and that the cracking distribution and failure mode of the slab depend on its reinforcement configuration, while the reinforcement configuration has a relatively slight influence on the ultimate bearing capacity. In addition,the role of GFRP bars is quantified, and the results obtained through the design method considering the arching action are more accordant with the experimental results than the calculated values based on current design standards are.

    Analytical Method of Elasto-Plastic Subgrade Reaction for Single Pile Subjected to Lateral Soil Movement
    Zhang Ai-jun Mo Hai-hong Zhu Zhen-de
    2012, 40(9):  153-159. 
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    Large lateral soil movement usually occurs in many unstable slopes due to the excavation or rainfall,which results easily in additional displacement and bending moment in adjacent stabilizing piles. In order to solve this problem,based on the Winkler foundation beam model,the simplified elasto-plastic constitutive relation of the pilelateral soil is adopted to simulate the nonlinear pile-soil interaction,and a set of four-orders differential governing
    equations based on the elasto-plastic subgrade reaction method are devised to describe the stabilizing pile-soil slope interaction. Then,the matrix expression of the analytical solutions of the pile response is deduced according to its continuity conditions on the sliding face and boundary conditions at the top and bottom of the pile. Finally,the analytical solutions obtained through the proposed method and the existing measured values in model tests are compared,thus verifying the reliability of the proposed analytical method.

    Safety Evaluation Method for Laminated Rubber Bearings of Bridge Based on Extension Theory
    Zheng Yi Jia Jin-qing Shen Xiao-jun Xiong Wei-shi Gao Fei Zhang Yan-nian
    2012, 40(9):  160-164. 
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    In order to comprehensively evaluate the safety performance of the laminated rubber bearings of bridges,a matter-element model based on some safety factors is constructed by using the matter-element theory and the extension mathematics as the theoretical framework. Then,the evaluation index system and evaluation criteria of the safety factors are built up,and the qualitative indexes are quantified. Moreover,each index is processed for it to be normalized and dimensionless,and a simple dependent function is used to determine the weight of each index. A case study shows that the proposed method is feasible,that is,it can not only accurately describe the safety grades of the bearings but also provide the distance between the adjacent safety grades,and can transform the bouncing type rating method in the current standard into the continuous rating method.

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