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15 December 2010, Volume 31 Issue 12 Previous Issue    Next Issue
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Comparative study on soft-sensor of grinding particle size Zhou, Ping (1); Chai, Tian-You (1) 2010, 31 (12):  1673-1676.  DOI: - Abstract ( 264 )   HTML   PDF (1848KB) ( 533 )   It is difficult to measure the grinding particle size (GPS) online directly, while the offline analysis with samples in lab will cause long time delay. The soft-sensor technique is therefore required to achieve the online estimation and closed-loop control of the GPS. Taking a practical two-stage grinding circuit as the objective to investigate, three GPS soft-sensor models were developed based on multiple regression, cased-based reason (CBR), and neural network (NN), respectively. These soft-sensor models were discussed comparatively via industrial tests. The results showed that the CBR soft-sensor model is superior to both the BP-NN soft-sensor model and the multiple regression soft-sensor model. References | Related Articles | Metrics

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Suppress methods of zero sequence circulating current for parallel PWM rectifiers Chen, Hong-Zhi (1); Wang, Xu (1); Liu, Jian-Chang (1); Yan, Shi-Jie (1) 2010, 31 (12):  1677-1680+1716.  DOI: - Abstract ( 298 )   HTML   PDF (1573KB) ( 745 )   Zero sequence circulating current of direct parallel PWM rectifiers will cause the rectifier power loss even the damage to switching members. If only the zero sequence current of rectifiers themselves is applied to the suppression of circulating current for feedback control, it is hard to avoid the competition between the zero sequence voltage of those rectifiers, thus causing the over modulation of the PWM signals. To solve the problems, the circulating current of PWM rectifier system was discussed in depth, with an integrated solution proposed to the suppression of zero sequence circulating current. In the solution voltage variable at the neutral point DC bus was introduced as the regulate point for AC power supply, and the way to regulate the circulating current was determined according to how the zero sequence current of all rectifiers affected the low-frequency component of the voltage. Simulation results verified the effectiveness of the proposed solution to the control of zero sequence current. References | Related Articles | Metrics

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An automatic navigation system based on SVM image segmentation for the blind Tian, Ya-Nan (1); Lei, Hong-Wei (1); Wang, Xu (1) 2010, 31 (12):  1681-1684.  DOI: - Abstract ( 621 )   HTML   PDF (1730KB) ( 685 )   In the conventional automatic navigation systems, images are directly mapped into those auditory representations which cover a lot of background information interfering in the blind's understanding of images. An automatic navigation system is therefore presented for the blind based on SVM image segmentation, where the images taken by a video camera are all segmented into two parts via SVM, i.e. object and background, and the former is enhanced with the latter removed by gray level transformation. Then, the object is mapped into auditory representation. Experimental results showed that the blind is able to understand the auditory display and form the cognition for the shape, size and position of an object after training. References | Related Articles | Metrics

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Automatic detection based on ballistocardiogram signal for abnormal heart rate Jiang, Fang-Fang (1); Wang, Xu (1); Yu, Yan-Bo (1); Yang, Dan (1) 2010, 31 (12):  1685-1688.  DOI: - Abstract ( 408 )   HTML   PDF (1109KB) ( 1109 )   Ballistocardiogram is an instrument to record the periodical fluttering caused by myocardial contraction without direct contact. As a signal of heart rhythm, the records are inevitably in association with heart rate. For this reason, a ballistocardiogram signal acquiring system was designed and implemented for sitting subjects with the single-channel electrocardiogram signal acquired synchronously. The BCG signal is so weak and easy to be jammed that the chaotic Duffing oscillators should be used to extract the periodic characteristics. Thus, a simplified phase state classification method was proposed according to the characteristics for the automatic detection of abnormal heart rate. Test results showed that although the ballistocardiogram signal after the pre-filtering is still noisy, the method proposed can automatically detect the subjects whose heart rate is abnormal. References | Related Articles | Metrics

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Corners matching algorithm based on measures of scale, distance and rotation Jia, Xu (1); Xue, Ding-Yu (1); Cui, Jian-Jiang (1) 2010, 31 (12):  1689-1692.  DOI: - Abstract ( 217 )   HTML   PDF (1473KB) ( 653 )   Because there is a topological invariance of location between true corner to be matched with other corners in neighborhood, a new corner matching algorithm based on measures of scale, distance and rotation is proposed to solve the drawbacks of conventional matching algorithms based on the similarity measure of gray levels. In this algorithm the corners are matched initially according to the phase-correlation, and every couple of corners to be matched is computed according to the measures of scale, distance and rotation. Then, whether a match is right or wrong is judged by the measure function values given by the computation. Some experimental results verified that the matching algorithm proposed is better than other conventional algorithms for matching corners. References | Related Articles | Metrics

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RBFN-based prediction for time series of process industries Liu, Fang (1); Mao, Zhi-Zhong (1); Li, Lei (1) 2010, 31 (12):  1693-1696.  DOI: - Abstract ( 256 )   HTML   PDF (460KB) ( 527 )   The key of residual-based outlier detection algorithm depends on the accurate prediction. To solve the problem, a prediction algorithm based on the improved RBFN (radial basis function network) is proposed for time series of process industries. In the algorithm the input form of the improved RBFN is changed so as to enable the improved RBFN to be more convenient for introducing the forgetting and penalty factors into it, thus adapting itself to the dynamic performance/robustness required by the residual-based outlier detection. The equivalence between the improved RBFN and conventional RBFN has been proved theoretically, and the comparative test results revealed that the former is simpler than the latter in network architecture with more definite attributes of parameter concerned. References | Related Articles | Metrics

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Application of improved differential evolution algorithm to task assignment Wu, Pei-Feng (1); Gao, Li-Qun (1); Zou, De-Xuan (1) 2010, 31 (12):  1697-1700.  DOI: - Abstract ( 283 )   HTML   PDF (978KB) ( 1106 )   An improved differential evolution (IDE) algorithm was proposed for task assignment by modifying two important parameters of DE algorithm: scale factor and crossover rate. The scale factor is adaptively adjusted according to the objective function values of all candidate solution vectors, and the crossover rate is dynamically adjusted with the increasing of iteration steps. The combination of such two parameters is able to not only increase the diversity of candidate solutions but also enhance the develop ability of solution space of the proposed algorithm. Experimental results demonstrated that the IDE algorithm has stronger convergence and higher stability than other three DE algorithms for task assignment. References | Related Articles | Metrics

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Fault diagnosis of broken rotor bars of induction motors via Hilbert transform and wavelet packet energy analysis Feng, Jian (1); Cao, Jian-Gang (1) 2010, 31 (12):  1701-1704.  DOI: - Abstract ( 259 )   HTML   PDF (1757KB) ( 624 )   Broken rotor bar fault of squirrel-cage motor is one of the most frequent faults, to which a new method of fault diagnosis was proposed via combining the Hilbert transform with wavelet packet energy analysis. By Hilbert transform, the DC component in the stator current is eliminated. The problem that the characteristic component of the fault of broken rotor bar is easy to be annihilated by fundamental wave and difficult to detect is addressed. Then, the fault was identified by wavelet packet energy analysis and the experimental results demonstrated the effectiveness of this method. References | Related Articles | Metrics

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Randoms correction algorithm for attenuation with three-rod source during reconstruction Teng, Yue-Yang (1); Zhang, Tie (1) 2010, 31 (12):  1705-1708.  DOI: - Abstract ( 265 )   HTML   PDF (485KB) ( 585 )   In PET (positron emission tomography) system, the single-rod source spends a lot of time on the photon-attenuated scan. Although the three-rod source can reduce the scanning time, it brings a lot of random coincidences. A restricted single-photon algorithm is therefore designed for randoms correction due to the three-rod photon-attenuated scan, i.e. to provide a random sinogram for each and every rod position so as to filter all by three fan-beam acceptance windows. Then, a practical random sinogram is provided comprising all filtered random coincidences. The algorithm was evaluated by the image quality and correction accuracy of attenuation as specified in NEMA standard. Experimental results showed that the proposed algorithm can obtain the same image quality and correction accuracy of attenuation just like what can be obtained from single-rod source with half of the photon-attenuated scanning time saved. References | Related Articles | Metrics

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Rapid detection technique for P2P-based botnets Yu, Ge (1); Yu, Xiao-Cong (2); Dong, Xiao-Mei (1); Qin, Yu-Hai (2) 2010, 31 (12):  1709-1712.  DOI: - Abstract ( 311 )   HTML   PDF (1119KB) ( 570 )   The attacks due to P2P-based botnet are increasingly one of the most serious threats to the Internet. The existing detection strategies for P2P-based botnets just focus on the offline detection methods by tracking the historical network traffic, which can hardly meet the requirement for real-time and precision. A new technique is therefore proposed to detect the P2P-based botnet activities rapidly, where an improved incremental classification technique is introduced to distinguish the P2P-based network traffic from others. Then a dynamical clustering technique and Boolean auto-correlation technique are presented to detect the suspected P2P-based botnet hosts which have the similarity and periodicity in communication behavior. The experimental evaluations showed that the technique proposed can implement the detection for P2P-based botnets rapidly and efficiently. References | Related Articles | Metrics

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An analysis of spatial multiplexing in mobile wireless sensor networks Li, Da-Zhou (1); Zhao, Hai (1); Zhu, Jian (1); Zhang, Kuan (1) 2010, 31 (12):  1713-1716.  DOI: - Abstract ( 297 )   HTML   PDF (804KB) ( 594 )   At present most of the researches on wireless sensor network focus on the protocols at different levels, network security, QoS and power control. However, the topological structure of network as the basis of the upper algorithm plays a decisive role in the performance of wireless sensor networks. The spatial multiplexing caused by the change in the topological structure of wireless sensor networks is described, with the spatial multiplexing ratio quantified. Then the characteristics of network connection topology of wireless sensor networks are proposed. As a result, an important reference is provided for the design of a dynamic network MAC protocol. References | Related Articles | Metrics

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Critical conditions for dendrite fragmentation of low carbon steel in travelling electromagnetic field Chen, Jin (1); Su, Zhi-Jian (1); Nakajima, Keiji (2); He, Ji-Cheng (1) 2010, 31 (12):  1717-1720+1732.  DOI: - Abstract ( 242 )   HTML   PDF (1185KB) ( 719 )   To investigate the effect of travelling electromagnetic field on dendrite fragmentation in solidification process, the 0.22 wt%~0.34 wt%C steel was tested for its solidifying behavior in travelling electromagnetic field. Observing the solidification structures of casting blanks under different magnetic flux density, the distributions of secondary dendrite arm spacing were investigated and the functional relationship between secondary dendrite arm spacing and cooling rate in solidification was discussed, as well as the effect of travelling electromagnetic field on the columnar-to-equiaxed transition (CET) position. The solidification rate and solid fraction when CET occurs were calculated. The critical conditions for dendrite fragmentation in travelling electromagnetic field is derived and verified by the testing results of low carbon steel. Thus, the relationship between the average velocity of the liquid-phase and the critical solid volume fraction when CET occurs was obtained. References | Related Articles | Metrics

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Preparation of high-wearability and self-lubricating anode oxide film on aluminum alloy surface Chen, Sui-Yuan (1); Yang, Yong-Ze (1); Liang, Jing (1); Liu, Chang-Sheng (1) 2010, 31 (12):  1721-1724.  DOI: - Abstract ( 366 )   HTML   PDF (1519KB) ( 1305 )   Using H2SO4, H2C2O4 and C7H6O6S · 2H2O as basic electrolyte with 0, 5, 15 and 25 mL/L PTFE emulsion taken as additives separately, the hard Al2O3-PTFE composite films were prepared on the surface of 2024 aluminum alloy. The structure, performance and formation mechanism of the composite films were studied by SEM, hardometer and tribo-wearometer. The result showed that the film sample thickness is 42 μm without PTFE added in, and it increases to 51 μm with PTFE added increasingly. The hardness tends to increase then decrease, and biggest hardness is 417 HV. When the concentration of added PTFE is 25 mL/L, the wear loss is 7 mg, i.e. about one third of that without PTFE added. The PTFE contained in the oxide film will form a lubricating layer when it is in contact with a frictional part, thus decreasing the friction coefficient to improve the wearability and self-lubricating performance of the anodizing film with its hardness kept up. References | Related Articles | Metrics

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Cooling temperature control of hot rolled steel strip and its self-learning Liu, Wei-Wei (1); Li, Hai-Jun (1); Wang, Zhao-Dong (1); Wang, Guo-Dong (1) 2010, 31 (12):  1725-1728.  DOI: - Abstract ( 311 )   HTML   PDF (1497KB) ( 603 )   Control precision of coiling temperature is one of the key factors influencing on the strip quality/shape during the cooling process of hot rolled steel strip. The temperature control precision is therefore the core of the mathematical model to control cooling process and, at the same time, the mathematical model should serve the function of self-learning to improve the temperature control precision. A mathematical model with nonlinear structural characteristics was developed to control the cooling process. Analyzing its self-learning ability, the model enables the key parameters to be corrected uninterruptedly so as to improve the temperature control precision and adaptability of the model. The in-situ application results verified that the mathematical model developed can provide high control precision of coiling temperature, thus laying a foundation for improving steel strip quality. References | Related Articles | Metrics

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Experimental investigation on shaft straightening based on laser cladding Zheng, Hui (1); Han, Zhi-Ren (2); Chen, Jiang (3); Wang, Guo-Dong (1) 2010, 31 (12):  1729-1732.  DOI: - Abstract ( 318 )   HTML   PDF (1245KB) ( 612 )   To investigate the feasibility of laser cladding technique in shaft straightening and what effects the technique will result in under different processing conditions, a relevant test was designed and implemented, where a CO2 laser was used for the shaft specimen whose eccentricity was measured with a dial gauge to indicate the flexibility of the specimen. In the test, the axial angle of laser was changed during laser cladding with both the length and depth of cladding area kept unchanged, then the depth was changed with the cladding area kept unchanged. The test results were verified with actual exemplifications and showed that the shaft is bent towards the laser beam. When the axis angle is smaller than 90°, the shaft flexibility is directly proportional to the cladding area and when the angle is greater than 90°, no obvious change in the flexibility is found. Furthermore, the shaft flexibility is directly proportional to the number of cladding layers if the cladding area is constant. All the results demonstrate that the technique proposed comes up to the expected effect. References | Related Articles | Metrics

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Analysis and solution to the problem of disorderly strip wrapping on Carrousel coiler Wang, Dong-Hong (1); Zhang, Yu-Chun (2); Di, Hong-Shuang (1) 2010, 31 (12):  1733-1736.  DOI: - Abstract ( 333 )   HTML   PDF (513KB) ( 669 )   How to solve the problem of disorderly strip wrapping on a Carrousel coiler used for a PL-TCM unit in China was investigated. The forces acted on the coiler in its coiling process was analyzed, thus revealing that the disorderly strip wrapping is essentially because of the internal bending stress of strip between the last mill stand and the coiler. Discussing the reason why the internal bending stress forms in strip, the problem of disorderly strip wrapping was solved via the mechanical measures taken appropriately. On the other hand, the quantitative relationship between the angular acceleration of the big rotating disc as a past of the coiler and its angular position during rotation was analyzed with the intention of providing theoretically the reference and solution to improve the stability of dynamic control of the coiling tension in the process of rotation of the big rotating disc. References | Related Articles | Metrics

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Supply-demand forecasting model of blast furnace gas in iron & steel works and its application Zhang, Qi (1); Gu, Yan-Liang (2); Ti, Wei (1); Cai, Jiu-Ju (1) 2010, 31 (12):  1737-1740.  DOI: - Abstract ( 333 )   HTML   PDF (1484KB) ( 838 )   With the blast furnace gas (BFG) system of an iron and steel works taken as an object, the relationship between the gas throughput and influencing factors on BFG generation/consumption was analyzed by grey correlation. A prediction model of BFG was developed on the basis of BP neural network for forecasting the supply and demand of BFG in the whole iron/steel-making process. The reasonability of the forecasting of BFG generation and consumption was discussed on various working conditions including normal operation and troubleshooting. The results showed that the forecasting model developed is of high precision with small errors and available to predict actually the BFG supply and demand so as to decrease the unnecessary BFG emission. The model is therefore able to lay a theoretical foundation to schedule the BFG utilization reasonably. References | Related Articles | Metrics

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Evaluation indices of gray water recycling system in iron and steel works Dong, Hui (1); Li, Zhi-Ming (1); Xiao, Sheng-Yan (1); Cai, Jiu-Ju (1) 2010, 31 (12):  1741-1744+1760.  DOI: - Abstract ( 248 )   HTML   PDF (1375KB) ( 656 )   The feasibility of gray water recycling system in iron and steel works and relevant evaluation indices were analyzed comprehensively. Then the evaluation indices of the system were given to evaluate the water-saving effects in the coking procedure of a certain iron and steel works quantitatively. The results showed that the water resource utilization efficiency as an index to evaluate the gray water recycling system is more reasonable and effective than those conventional indices as concentration multiple and recycling rate which are restrictive. For iron and steel works, the water resource utilization efficiency will increase 20, the quantity of industrial fresh water is decreased by 0.752 m3 per ton of coke and the annual quantity of industrial fresh water saved comes up to 5.34 million tons if the water reuse ratio is 0.5. References | Related Articles | Metrics

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Analysis of sensitivity to BFG combustion Liu, Hui (1); Li, Ben-Wen (2); Chen, Hai-Geng (1); Chen, Wen-Zhong (1) 2010, 31 (12):  1745-1748.  DOI: - Abstract ( 443 )   HTML   PDF (1885KB) ( 1019 )   Simplifying of the complex reaction mechanism is of importance to the numerical simulation of the combustion of BFG (blast furnace gas). The software CHEMKIN was used to solve a one-dimensional mathematical model of steady-state pre-mixing laminar combustion. By analyzing the effects of basic components of BFG on the combustion rate in all elementary reactions, the simplified reaction mechanism was obtained and becomes the basic mechanism of BFG combustion. Compared the computed result by the simplified mechanism with that by complex mechanism, the time required for the former was less than 1 s but that for the latter was about 18 s. The differences between molar fractions of the BFG components computed by the two mechanisms were less than 0.4%. The reliability of the simplified reaction mechanism is therefore verified. References | Related Articles | Metrics

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Kaolin-containing wastewater treatment by PAFC prepared with red mud Lu, Gui-Lin (1); Yu, Hai-Yan (1); Chi, Song-Jiang (2); Bi, Shi-Wen (1) 2010, 31 (12):  1749-1752.  DOI: - Abstract ( 350 )   HTML   PDF (1270KB) ( 649 )   To recover aluminum and iron from red mud and, simultaneously, prevent the environment pollution and occupancy of large-area land from the recovery, the polyaluminium ferric chloride(PAFC) was prepared with red mud, to treat the kaolin-containing wastewater. A contrast test was carried out with PAFC and PAC(polyaluminium chloride) both used as flocculants to investigate the effects of the dose of flocculants, the pH value, concentration and temperature of wastewater, and basicity on flocculation. The results indicated that all the influencing factors as above except the wastewater temperature affect the flocculation greatly. The maximum depollution rate by PAC is 93%, while that by PAFC comes up to 96%. References | Related Articles | Metrics

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Load-strength interference model based on correlation analysis Gao, Peng (1); Xie, Li-Yang (1) 2010, 31 (12):  1753-1756.  DOI: - Abstract ( 328 )   HTML   PDF (1421KB) ( 588 )   The conventional load-strength interference model is suitable for the static reliability analysis of a component, where the load is independent of strength. With the strength degradation taken into account, the residual strength of a component is the function of the magnitude and frequency of loading. The conventional load-strength interference model is therefore unable to analyze the reliability of a component or system if the strength is in degradation. By defining the equivalent coefficient of the loading frequency and referential load, a load-strength interference model considering the correlation between the load and the strength is developed, which can be used to evaluate the reliability of a component or system in strength degradation under random load. In addition, the common cause failure due to sharing the same random load affects greatly the reliability analysis of a system. A reliability model is developed for the system considering the common cause failure is derived. A numerical example is given to show the rationality and effectivity of the reliability model. References | Related Articles | Metrics

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Study on chaos and fractal dimension of an economic time series Liu, Yong-Xi (1); Li, He (1); Zhao, Xi-Nan (2); Wen, Bang-Chun (1) 2010, 31 (12):  1757-1760.  DOI: - Abstract ( 281 )   HTML   PDF (1649KB) ( 536 )   To find out the internal dynamic characteristics of economics fluctuation, the possibility of the existence of chaotic behavior in a city's power consumption fluctuation is analyzed nonlinearly. Based on the city's data logging of power consumption in recent years, the different methods are used to analyze the chaotic dynamics, such as the phase space reconstruction, amplitude spectra and Poincare's mapping. The correlated fractal dimension calculated. As a result, the saturated embedded dimensions are 7 and the correlation fractal dimension is 0.834, and a judgment is thus primarily made that the process of power consumption in the city is chaotic. The dynamically chaotic characteristics of power consumption fluctuation is therefore proved rigorously, thus providing a theoretical basis for studying the relevant forecasting of chaos. References | Related Articles | Metrics

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Key factor value and method to determine digging resistance Lin, Gui-Yu (1); Li, Ai-Feng (2); Li, Kui-Xian (1) 2010, 31 (12):  1761-1764.  DOI: - Abstract ( 297 )   HTML   PDF (2723KB) ( 614 )   How to determine the digging depth is the key factor and also a problem which is often difficult to be tackled in determining the digging resistance for the ore piles and the piles after blasting. Based on the typical digging process for a blasted ore pile and the principle that the volume digged by a shovel dipper is equal to the volume of the dipper, a mathematical model is developed of digging depth with an equation of digging path given. Then, the mathematical relationship between the maximum digging depth and inside width of dipper is given on the extreme principle, which is in conformity to the measured values. Furthermore, the digging resistance and its maximum value in the whole digging process are both given. In this way a new method is proposed to determine the key factor value of digging resistance, thus providing a reliable reference for determining other mechanical parameters. References | Related Articles | Metrics

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Effects of ocean physicochemical factors on growth of hermatypic corals Yang, Li-Li (1); Gong, En-Pu (1); Zhang, Yong-Li (1); Chang, Hong-Lun (1) 2010, 31 (12):  1765-1768.  DOI: - Abstract ( 373 )   HTML   PDF (1111KB) ( 1075 )   Based on existing data, the effect of single factor environmental change on the growth of hematypic coral was investigated. The growth of coral reef is controlled by sea-level so as to form its functional skeleton adaptable to eustatic sea-level fluctuations. Rise in atmospheric CO2 level can decrease the CO32- concentration in seawater and reduce the saturabilities of CaCO3 minerals(mainly the aragonite and calcite), thus slowing the calcification process of hematypic coral and threatening seriously the oceanic environment where the ecological system of growing hematypic coral relies on. The high ratio of x(Mg) to x(Ca) of aragonite sea in the Late Paleozoic was disadvantageous to the growth of low-magnesian calcite rugose coral but, on the contrary, advantageous to the modern aragonite hexacoral. Water eutrophication can easily induce the symbiodic algae to go out of coral polyp host and make the coral albinistic even dead. References | Related Articles | Metrics

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Study on characteristics of percolation in rock failure process via acoustic emission locating technique Liu, Jian-Po (1); Li, Yuan-Hui (1); Yang, Yu-Jiang (1) 2010, 31 (12):  1769-1772.  DOI: - Abstract ( 251 )   HTML   PDF (1532KB) ( 626 )   Experiments for rock failure process under uniaxial compression were carried out via the acoustic emission (AE) locating techniques to study the evolution process of failure elements and percolation characteristics during rocks failure. The results showed that the 3-D location of AE events directly reflects the processes of initiation, propagation and evolution of micro-cracks. Dividing the failure elements in rocks by locating AE events, the orderly and centralized self-organizing evolution of failure elements was shown from random distribution. Before the rock failure due to instability, the number of failure clusters and the relationship of negative power exponent between the scale and the number of failure clusters tend to increase slowly, which suggests that the failure elements begin to swarm in a large area, thus causing the rock in stable fracture phase to turn into unstable fracture phase. When the probability of failure comes up to a certain value, the strain of rock begins increasing abruptly. The experimental study on rock percolation via dividing failure elements in accordance to AE locating events is a new way for studying rock failure mechanics. References | Related Articles | Metrics

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On the deformation monitoring based on integrating InSAR with GPS for expressway/goaf Rui, Yong-Qin (1); Chen, Jia-Yi (2); Ding, Xiao-Li (3) 2010, 31 (12):  1773-1776.  DOI: - Abstract ( 458 )   HTML   PDF (1305KB) ( 1072 )   Integrating InSAR with GPS data, how to monitor and evaluate the influence of goaf on expressway was investigated. To unwrap the sparse phases in the deformation information on expressway as extracted from D-InSAR bands, LAMBDA phase unwrapping algorithm commonly used in GPS is proposed with an appropriate resolving model developed to acquire the deformation time-series for the expressway with goaf from D-InSAR bands so as to keep abreast of new development of the influence of goaf on expressway. While the radar satellite is in transit, the 3rd class leveling is used to measure the deformation to verify the monitoring feasibility of expressway deformation. The experimental results showed that the expressway/goaf deformation monitoring via integrating InSAR with GPS is feasible and reliable and has broad prospects in applications. References | Related Articles | Metrics

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Dynamic analysis of ecological sustainability of mine economic system Gu, Xiao-Wei (1); Wang, Zhong-Xin (2); Feng, Min (1); Wang, Qing (1) 2010, 31 (12):  1777-1781.  DOI: - Abstract ( 265 )   HTML   PDF (1551KB) ( 463 )   A method was proposed to assess dynamically the ecological sustainability of the economic system in the Nanfen open pit mine empirically, based on the ecological footprint in the period from 1995 to 2007. The results showed that all the annual ecological footprint indices were smaller than -100% in the period, and the ecological deficits per RMB 10000 industrial output fluctuated with an amplitude of 0.01 hm2 · (RMB 10000)-1, with the average growth rate of annual industrial output values up to 12.79%. Although the average coefficient of elasticity of ecological footprints corresponding to economic development in the period was 1.27, the average growth rate of ecological bearing capacity was only 2.85%. A conclusion is therefore drawn that the future development of the economic system in the mine may be restricted by the limited supply of local ecological resources, thus coming into an unsustainable state. References | Related Articles | Metrics

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Research on performance of the modified asphalt by diatomite-cellulose composite fiber Chen, Xiao-Long (1); Sun, Yong-Sheng (1); Han, Yue-Xin (1); Zhang, Bin (1) 2010, 31 (12):  1782-1785.  DOI: - Abstract ( 327 )   HTML   PDF (802KB) ( 614 )   The diatomite-cellulose composite fiber (DCCF) is made from diatomite and cellulose fibers and prepared via specific surface treatment under high shearing conditions. The DCCF was used to modify the asphalt for pavement, then the high/low-temperature performance and temperature susceptibility of the modified asphalt were investigated experimentally. The results showed that these performances of the DCCF-modified asphalt are all improved obviously and will be the best if the modifier dosage is 0.5%. After the modification the penetration index increases by 2.43, the equivalent softening point increases by 7.7°C and the equivalent brittle point decreases by 16.8°C in comparison to the asphalt matrix without modification. References | Related Articles | Metrics

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Calculation of axial force acting on GFRP-concrete composite beam via energy method Qin, Guo-Peng (1); Wang, Lian-Guang (1) 2010, 31 (12):  1786-1789.  DOI: - Abstract ( 261 )   HTML   PDF (1742KB) ( 494 )   The GFRP-concrete composite beam, i.e. combining the GFRP tube with concrete slab, is available to work by means of the shear connectors as flexible connectors. However, the connectors will be deformed when transferring interfacial shear force, thus causing the slip between GFRP tube and concrete slab. The interfacial slip will result in the stress redistribution between GFRP tube, concrete flange plate and shear connectors. Based on the principle of minimum potential energy and according to the structural and load bearing characteristics and variational principle, some differential equations of axial force are derived taking account of the effect of interfacial slip, as well as the theoretical formulae of the axial force acting on both the concrete slab and GFRP tube in the composite beam under symmetrically concentrated load. The calculated results showed that the axial force acting on the composite beam increases with the increasing connector stiffness and external load and decreases with the increasing wall thickness of GFRP tube. And the maximum axial force is found at the midspan, then it decreases gradually from midspan to beam end where it is approximately zero. References | Related Articles | Metrics

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Testing investigation on effects of mixing, vibrating and curing on strength of high-performance concrete Cheng, Yun-Hong (1); Gou, Zhen-Zhi (1); Wang, Yuan (2) 2010, 31 (12):  1790-1793.  DOI: - Abstract ( 440 )   HTML   PDF (581KB) ( 680 )   9 groups of high-performance concrete specimens were designed for orthogonal test where each of the 3 factors was at 3 levels with an L9(34) orthogonal table set out. The three factors/levels were the mixing at artificial, mechanical and overtime levels; the vibrating at artificial, mechanical and non-vibrating levels and the curing at natural, standard and humidity-insulated levels. The compressive strength tests for the 9 groups of high-performance concrete specimens were carried out for 14 days and 28 days separately, then the differential analysis and variance analysis were made for the orthogonal test results. The analyses indicated that among the three influencing factors on the compression strength of the high-performance concrete the mixing, curing and vibrating are ranked the first, second and third, respectively, and the optimal modes(levels) are the overtime mixing, non-vibrating and humidity-insulated curing. References | Related Articles | Metrics

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On the enterprises' recycling decision-making model within EPR framework Zheng, Yun-Hong (1) 2010, 31 (12):  1794-1797.  DOI: - Abstract ( 239 )   HTML   PDF (1474KB) ( 684 )   The recycling modes of EOL products are divided into three kinds, i.e. the producer's self-recycling, outsourcing and alliance organized by several corporations. With the characteristics of the different recycling modes discussed, a decision-making model is developed within the framework of EPR(extended producer responsibility) for the recycling behavior of enterprises in view of the decision on benefits, then the maximum benefit and the conditions under which it is available are discussed and expounded for different recycling modes. Such a conclusion is therefore drawn that the cost saving as a result of recycling materials is an increasing function of the profit arising from the recycling behavior of an enterprise and that the scale structure of a recycling alliance determines the cost for material recycling. References | Related Articles | Metrics

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A new deviation analysis model and its application Han, Ying (1); Gao, Dong-Wei (1); Wang, Juan (1); Liu, Feng-Yuan (1) 2010, 31 (12):  1798-1802.  DOI: - Abstract ( 267 )   HTML   PDF (1711KB) ( 593 )   A method of complete decomposition of interactive terms was proposed so as to develop a new deviation analysis model via SDA which is available to analyze the nonlinearity efficiently, thus solving the problem of the inconsistency of interactive terms in the SDA-based input-output deviation analysis model. The new model was applied to the annual input-output data in 1997, 1999, 2000, 2002 and 2007 to analyze China's economic growth in view of the industrial structure, intrinsic structure of finished products and the direct and interactive effects of finished product on China's primary, secondary and tertiary industries. The conclusion thus drawn is in conformity to the economic situation from 1997 to 2007 in China and of significance to the forecast of China's economic development trend and relative policy making. References | Related Articles | Metrics