Journal of Northeastern University(Natural Science)

Design of virtual object of tandem cold rolling simulation system

Tie, Ming (1); Chai, Tian-You (2)

2007, 28 (6): 761-764. DOI: -

Abstract ( 227 )

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A tandem cold rolling simulation system with 4-level architecture was developed for the 4-high 5-stand mill system for 2030 mm sheet in a steel plant. The structure and functions of the virtual object are introduced to give a description of the dynamics of rolling process and physical device. A distributed database system (DDP3S) was developed for the virtual object, and the modularization design of the simulation software improved its security and maintainability. The application, client and resource hierarchies of the virtual object which the Web-based simulation platform comprises are thus implemented and presented. This virtual object of tandem cold rolling simulation system provides an appropriate platform for virtual rolling experiments to improve rolling automation technique.

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Robust and decentralized fuzzy hyperbolic H∞ control of a class of nonlinear large-scale systems

Liu, Xin-Rui (1); Zhang, Hua-Guang (1)

2007, 28 (6): 765-768. DOI: -

Abstract ( 272 )

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Robust fuzzy hyperbolic H∞ control of nonlinear large-scale systems with parametric uncertainties is studied introducing the fuzzy hyperbolic model (FHM) to approximate to some complex large-scale systems. Then, according to the direct Lyapunov method and decentralized control theory of large-scale systems, a state feedback H∞ controller based on FHM is used such that the sufficient condition can be given in terms of linear matrix inequalities to enable the systems to satisfy the H∞ performance indices. The superiority of FHM over Takagi-Sugeno (T-S) fuzzy model in practice is mainly that no identification of premise structure and complete parameter space are needed, especially FHM costs obviously less than T-S fuzzy model in computation when a lot of fuzzy rules are needed to approximate to highly complex nonlinear systems. A simulation example is given to illustrate the feasibility and validity of the design procedure proposed.

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Quadratic stability of a class of hybrid impulsive and switched singular systems

Yin, Yu-Juan (1); Zhao, Jun (1)

2007, 28 (6): 769-772. DOI: -

Abstract ( 238 )

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A model of a class of hybrid impulsive and switched singular systems is developed, based on a kind of controlled singular systems and hybrid impulsive and switched control. The design of hybrid impulsive and switched control for the system is investigated under the condition that the number of candidate controllers is limited. A sufficient condition of quadratic stability for the impulsive and switched systems is given with a switching law by way of convex combination and single Lyapunov function. According to the restricted system equivalence of singular systems and their structural characteristics, an allowed impulsive control is provided to ensure the consistent state and make the system to be quadratically stable. An example is given to illustrate the effectiveness of the design proposed.

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Control for nonlinear discrete singular systems

Yi, Na (1); Yang, Dong-Mei (1); Zhang, Qing-Ling (1); Li, Qin (1)

2007, 28 (6): 773-776. DOI: -

Abstract ( 283 )

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The design of state feedback H∞ controller is discussed for nonlinear discrete singular systems. By means of generalized Lyapunov function and linear matrix inequality (LMI), the asymptotical stability with zero solution is studied for the system, and a sufficient condition is given such that the system is asymptotically stable with zero solution and also a H∞ norm constraint. And a state feedback H∞ controller is designed to guarantee the performance of the resultant closed-loop system. A numerical example is given to illustrate the feasibility and validity of the conclusion drawn.

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Adaptive image de-noising algorithm based on fuzzy logic

Shi, Zhen-Gang (1); Gao, Li-Qun (1); Ge, Wen (1)

2007, 28 (6): 777-780. DOI: -

Abstract ( 305 )

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A new adaptive image de-noising algorithm based on fuzzy logic is proposed by analyzing the deficiencies of median filter when it is used to eliminate impulsive noise. The new algorithm for detection of noise points is based on grayscale distribution of neighboring pixels in different directions, and it uses the improved algorithm of maximum-minimum exclusive median method to estimate the gray level of current noisy pixels. Introducing the fuzzy logic rules into the new algorithm, the gray level of noisy pixels will be restored more reasonably. Simulation results show that the new algorithm may bring about better effect in eliminating impulsive noise in comparison with the improved median filter methods.

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Soft-sensing modeling of a fermentation process through support vector machines and genetic algorithms

Sang, Hai-Feng (1); He, Da-Kuo (1); Zhang, Da-Peng (1)

2007, 28 (6): 781-784. DOI: -

Abstract ( 242 )

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A soft-sensing model is developed for on-line estimate of biomass concentration based on support vector machines. And genetic algorithms are introduced in selection of model input and the parameters of support vector machines. The purpose is to find out the input characteristic variables which contribute most to the model's estimation result for reducing the number of dimensions of space to input and scope of the problem to solve, thus decreasing the difficulties in computation and training practice. Meanwhile, the decision function can be obtained better to improve the performance of support vector machines by way of readjusting parameters. The training/verifying data of the model are all based on the actual experimental process, i.e. Nosiheptide fermentation. Result shows that soft-sensing model optimized by genetic algorithms is highly beneficial to the estimate of biomass concentration.

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On-line optimization algorithm for interstand tension setting during tandem cold rolling

Zhou, Wei (1); Wang, Xu-Guang (1); Zhang, Shu-Hong (1)

2007, 28 (6): 785-788. DOI: -

Abstract ( 291 )

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Based on the genetic algorithm with embedded fuzzy rules and a 0-1 integer planning model thus set up, an online optimization algorithm is developed for interstand tension setting during tandem cold rolling. The algorithm can improve productivity and products' quality with energy saved in addition to its high computing speed and online self-learning feature. The result of interstand tension setting optimization on tandem cold rolling mill for 1767 mm strip indicated that the genetic algorithm with embedded fuzzy rules can optimize online the interstand tension setting decision and play an reference role in exploring further the high-efficiency running of the tandem mill.

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Integrated QoS multicast routing algorithm based on bipopulation-evolution

Wang, Xing-Wei (1); Li, Shan-Lin (1); Huang, Min (1)

2007, 28 (6): 789-792. DOI: -

Abstract ( 279 )

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A non-NP QoS multicast routing algorithm in IP/DWDM optical Internet is proposed. It is based on the bipopulation-evolution to find a cost-optimized QoS multicast routing tree of which all bandwidth, delay, delay jitter, error rate are bounded with routing and wavelength assignment solved integratedly. Simulation results show that the proposed algorithm is both feasible and effective, which not only satisfies QoS constraints but also is superior to the algorithms based on the conventional genetic algorithm, getting rid of prematurity and slow convergence, the problem of QoS multicast routing in IP/DWDM optical Internet is therefore solved effectively.

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Robust adaptive beamforming algorithm based on a bayesian approach

Song, Xin (1); Wang, Jin-Kuan (1); Han, Ying-Hua (1); Wang, Han (1)

2007, 28 (6): 793-796. DOI: -

Abstract ( 271 )

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When applying adaptive arrays to actualities, the performance of existing adaptive array algorithms degenerates substantially because of the slight mismatch between actual and presumed array responses to expected signal. With the recursive process given, a novel robust adaptive beamforming algorithm is therefore proposed using Bayesian approach to respond to the current environment by learning or estimating the direction of arrival (DOA) of the actual signal from observations. The computational complexity of the proposed algorithm can thus be efficiently reduced in comparison with other algorithms since the recursive method is used to obtain inverse matrix, and it can provide excellent robustness for the uncertainty of DOA of actual signal and make the mean output array SINR consistently close to the optimal one. Simulation results reveal that the algorithm proposed is superior in performance to conventional ones.

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Adaptive searching algorithm based on P2P-SIP framework

Geng, Fu-Quan (1); Gao, Shi-Kun (1); Zhao, Lin-Liang (1); Wang, Guang-Xing (1)

2007, 28 (6): 797-800. DOI: -

Abstract ( 262 )

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Proposes an adaptive searching algorithm based on statistical analysis to solve the problem that the resource searching path is too long in P2P-SIP framework. The P2P-SIP system is sensitive to searching delay, and the increase in the probability of network change or the number of network nodes will lengthen greatly its searching delay. According to the statistic analysis of messages sent and received, the algorithm determines whether to send packages along the resource path to reduce searching delay and provide the algorithm with fault-tolerance via linear smoothing. It can be applied to present P2P searching algorithm to improve its searching efficiency. Theoretical analysis and simulation results show that the algorithm works better with P2P-SIP.

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Self-localization algorithm for wireless sensor network

Liao, Xian-Lin (1); Geng, Na (1); Shi, Kai (1); Zhao, Lin-Liang (1)

2007, 28 (6): 801-804. DOI: -

Abstract ( 273 )

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In wireless sensor networks, the node self-localization is vital and promising to a wide scope of both military and civilian applications. In this respect there are two types of algorithms, i.e. range-based and range-irrelevant, either has its own advantages and disadvantages. Taking account of those of the two algorithms, a low-cost and practical algorithm is proposed, using RSSI (received signal strength indicator) for range measurement between nodes and propagating the cumulative range in meter in a multijetter network, then localizing nodes geometrically via maximum likelihood estimation. Simulation results showed that by the algorithm the average error is 10%, while the position error is about 20% of nodes' RF transmission range if the ratio of anchor nodes is 10%.

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Application of workflow technology to medical image algorithm platform

Jia, Tong (1); Zhao, Da-Zhe (1); Li, Wei (1); Wang, Xu (2)

2007, 28 (6): 805-808. DOI: -

Abstract ( 229 )

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The conventional algorithm platform is just a function-oriented one whose algorithm flow is fixed without flexibility and unable to meet the current requirement for rapid development of medical image algorithm. Introducing the workflow technology, an integrated medical image algorithm platform was built using relevant modules and multi architecture to provide an algorithm flow available to dynamic management. A listing module of algorithm management is given as example to analyze how the workflow works in the platform and its advantages. Based on the algorithm platform, a computer-aided diagnosis (CAD) prototype system was developed for lung cancer of which the algorithm flow can be defined flexibly. The clinical testing for lots of lung cancer patients revealed that its high detection sensitivity of lung nodule can meet basically the requirement of clinical diagnosis.

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Effect of austenite deformation on phase transformation and microstructure of a weathering steel

Wu, Hong-Yan (1); Du, Lin-Xiu (1); Liu, Xiang-Hua (1); Dong, Jun-Hua (2)

2007, 28 (6): 809-812. DOI: -

Abstract ( 236 )

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Continuous cooling transformation (CCT) curves were plotted for the austenite before and after the compression deformation at 850°C, as a result of an investigation on a weathering steel which was tested on MMS-100 tester by means of dilatometry in combination with Vickers hardmeter. Optical microscope and SEM were employed to investigate the influences of cooling rate and deformation process on the transformation behavior and microstructure. Experimental results showed that in the whole deformation process the starting phase-transformation temperature increases with the polygonal ferrite area moving towards top left corner on the curve diagrams, thus increasing the critical cooling rate of ferrite plus pearlite. The deformed austenite suppresses the growth of bainitic ferrite by its tangled dislocation, then results in the refinement of microstructure.

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Heat transfer analysis of round billet mold during electromagnetic soft-contacting continuous casting

Kang, Li (1); Wang, En-Gang (1); He, Ji-Cheng (1)

2007, 28 (6): 813-816. DOI: -

Abstract ( 198 )

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Aiming at the process of electromagnetic soft-contacting continuous casting, a three-dimensional finite element model of electromagnetic field and temperature field was developed to investigate the influences of power frequency, current intensity, heat flux between casting billet and copper mould and heat conductivity of thermal insulation material on the temperature field. The results showed that in comparison to the conventional continuous casting mold, the wall temperature of copper mold increases under the action of electromagnetic field, and the higher the current intensity and frequency, the higher the peak value of mold wall temperature. The magnitude of heat flux determines directly the temperature distribution of copper mould. The bigger the heat flux, the clearer the heterogeneity of temperature along the mold axis, and the circumferential temperature gradient in mold increases because of material's uncontinuity. The conductivity of filled insulation affects greatly the temperature distribution on the wall of copper mould. When the heat conduction coefficient of insulation is lower, there are two axial temperature peak values which correspond to the two ends of a seam on the wall of copper mould, and they will increase axial temperature gradient of copper mould.

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Heat-treatment process for semi-solid Al-Cu-Mn alloy forgings and microstructure

Dong, Wei-Guo (1); Yin, Xiang (1); Wang, Ping (1); Lu, Gui-Min (1)

2007, 28 (6): 817-820. DOI: -

Abstract ( 246 )

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Different solution-ageing processes were carried out by way of orthogonal experiment for the semi-solid Al-Cu-Mn alloy forgings. Then, the resultant hardnesses were analyzed to determine the optimal technological parameters in such a heat-treatment, with the microstructure after ageing discussed. It was revealed that the Vickers hardness number can come up to over 130 MPa if the temperature/time of solution hardening and of age hardening are 540°C/13 hr and 165°C/8 hr, respectively, with the precipitated phases distributed uniformly and dispersedly on the matrix.

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Fabrication of hydroxyapatite/Ti network composites

Xiu, Zhi-Meng (1); Cui, Jian-Dong (1); Bai, Hua (1); Sun, Xu-Dong (1)

2007, 28 (6): 821-824. DOI: -

Abstract ( 192 )

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Hydroxyapatite (HA) powder was synthesized by sol-gel method with Ca(OH)2 and H3PO4 as reactants. The HA was coated with T1H2 powder using mechanical mixing method. Then the pure HA ceramics and HA/Ti composite were fabricated by hot-pressing. XRD results indicated that the predominant phase of the powder synthesized by sol-gel method and heat-treated at 900°C for 2 h is HA with a bit of CaO. The predominant phases of the HA/20vol%Ti composite that was hot-pressed at 1050°C were HA and Ti, with Ca2P2O7 and Ca3(PO4)2 shown at the same time. The fracture toughness and bending strength are 2.4 MPa·m^-1/2 and 54 MPa for HA-25vol%Ti composite hot-pressed at 1050°C, respectively, higher than pure HA ceramic. The microstructure showed that there is a netty distribution of the metal Ti in the composite, which is beneficial to the resistance to crack propagation because the mechanism of crack bridging.

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Kinetic model for dissolution of chromium ore in CaO-SiO2-MgO-Al2O3 slag system

Liu, Yan (1); Jiang, Mao-Fa (1); Wang, De-Yong (1); Xu, Li-Xian (1)

2007, 28 (6): 825-828. DOI: -

Abstract ( 202 )

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To reveal in depth the smelting/reduction mechanism of chromium ore in converter, the dissolution rate of natural chromium ore in definite shape in CaO-SiO2-MgO-Al2O3 slag system was determined, and a kinetic model for its dissolution process was developed on macrokinetics theory. The results showed that the dissolution process of chromium ore is controlled by the surface dissolution reaction on conditions of the experiments we did, where the temperature has significant effect on the reaction rate constant of chromium ore dissolution. The calculated value of dissolution activation energy is 524.52 kJ/mol. The dissolution rate of chromium ore in slag increases with reaction temperature.

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Numerical simulation of innovative ironmaking technologies applied in blast furnace process

Chu, Man-Sheng (1); Guo, Xian-Zhen (2); Shen, Feng-Man (1); Yagi, Jun-Ichiro (3)

2007, 28 (6): 829-833. DOI: -

Abstract ( 430 )

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A multi-fluid blast furnace model was used for the numerical simulation of some innovative ironmaking technologies to evaluate how the relevant operations affect blast furnace process and production indices. Those new ironmaking technologies included injecting hydrogen-bearing materials for hydrogen-enriched reduction, charging CCB for low-temperature ironmaking and recycling top gas to enhance the utilization of carbon and hydrogen. The simulation results of the model revealed that the application of those new technologies will bring the blast furnace process to super-high-efficiency operation, i.e. high productivity, lower energy consumption and lower CQ2 emission.

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Fluidity discussion on binding phase in fluorine-containing sinter

Li, Guang-Sen (1); Wei, Guo (1); Li, Xiao-Gang (2); Shen, Feng-Man (1)

2007, 28 (6): 834-838. DOI: -

Abstract ( 213 )

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An experimental investigation was done for the physical characteristics of the binding phase in fluorine-containing sinter used in Baotou Steel, especially its fluidity. By readjusting the basicity of the binding phase, i.e. w(CaO)/w(SiO2), and the content of MgO, CaF2 and FeO and measuring the viscosity and surface tension of the as-molten binding phase, the physical changing behavior of the binding phase was found. The results showed that if the basicity is 1.4 the viscosity and melting temperature of binding phase are both the lowest while the surface tension increases with rising basicity. Adding properly the MgO into the sinter can lower the viscosity of binding phase, while the surface tension increases with increasing content of MgO and the melting temperature becomes the lowest if MgO is 5wt%. Adding CaF2 can obviously decrease the viscosity and surface tension. The viscosity and surface tension decrease with the increasing content of FeO.

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Preparation of aluminum-magnesium alloys from magnesium oxide

Yang, Shao-Hua (1); Ban, Yun-Gang (1); Guo, Yu-Hua (1); Qiu, Zhu-Xian (1)

2007, 28 (6): 839-842. DOI: -

Abstract ( 309 )

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Aluminum-magnesium alloys were prepared through molten salt electrolysis from magnesium oxide. In the test, the liquid Al was taken as cathode with graphite as anode to produce CO and CO2 instead of a big amount of toxic or harmful gases released from conventional magnesium electrolysis. It was revealed that the content of Mg in Al increases gradually and up to 1%-5wt% with lengthening electrolyzing time, and the solubility of MgO can be improved by over 30% if 10wt% KC1 is added into electrolyte. CeF2 can lower the initial crystallization temperature of electrolyte, while the viscosity of electrolyte can be increased. The maximum current efficiency comes up to 74.5% within the first 45 min, then it decreases sharply, even below 40% after 2 hours.

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Deterioration mechanism of cathode in 300 kA prebaked anode aluminum reduction cells

Ren, Bi-Jun (1); Shi, Zhong-Ning (1); Liu, Shi-Ying (1); Qiu, Zhu-Xian (1)

2007, 28 (6): 843-846. DOI: -

Abstract ( 303 )

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The deterioration mechanism of a 300 kA large-scale prebaked aluminum reduction cell was studied. After a shutdown, the cell was dissected dryly for sampling analysis and observation, then the deterioration of carbonized cathode was investigated, such as breakage, leaks and surface corrosion pits. It was revealed that the causes of cathode's expansion cracking are mainly the sodium penetration, Al4C3 formed on cathode surface, electrocapillarity and electrolyte penetration into cathode gaps. Discusses the influencing factors on the service life of the cells were carried out. To lengthen the service life of the reduction cell, the following measures are regarded as efficient and suggested to take: improving the quality of carbonized cathode, strengthening the management of electrolysis cell from the very beginning and introducing such newly-developed materials and technologies as the graphitized cathode. In this way the voltage drop on cell bottom can be decreased so as to maintain well the cell wall.

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Preparation of nanocrystalline nickel ferrite and its electromagnetic properties

Ma, Rui-Ting (1); Tian, Yan-Wen (1); Bi, Shao-Dan (2); Zhang, Chun-Li (2)

2007, 28 (6): 847-850. DOI: -

Abstract ( 329 )

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Nanocrystalline nickel ferrite was prepared by polyacrylamide gel, taking acrylamide as monomer and N, N-methylenediacrylamide as lattice agent. FT-IR spectrometer, XRD, TEM and waveguide were used to characterize the gel, products and their electromagnetic properties after calcining. XRD patterns showed that the dried gel is amorphous, the spinel nickel ferrite formed at not lower than 400°C. The grain sizes and M-O characteristic absorption bonds are dependant on heat treatment temperature. When the calcining temperatures are 400, 600 and 800°C, the grain sizes are 8, 25 and 40 nm, respectively, as identified by TEM. The FT-IR spectra illustrated that the M-O characteristic absorption bonds shift from 590 cm² to 613 cm^-1. The nanocrystalline presents not only dielectric loss but magnetic loss in the frequency range of measurement, and both the losses of spinel-type nanocrystalline increases obviously with increasing heat treatment temperature.

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Influence of lanthana on specific surface area of γ-Al2O3 at high temperature

Liu, Xiao-Jun (1); Yu, Hai-Yan (1); Yang, Yi-Hong (1); Bi, Shi-Wen (1)

2007, 28 (6): 851-854. DOI: -

Abstract ( 318 )

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The thermal stability of γ-Al2O3 at high temperature was studied and simulated industrially in lab, focusing mainly on the influence of the preparation of La2O3 and γ-Al2O3 on the thermal stability of γ-Al2O3. It was found that when using[La (EDTA)]^- as liquid impregnant, keeping properly its concentration can suppress both the reducing specific surface area of γ-Al2O3 and its transform trend towards α-Al2O3 at high temperature, thus improving the thermal stability of γ-Al2O3 to keep its specific surface area bigger. For instance, specific surface area of the samples in which with 1%[La(EDTA)]^- roasted at 1200°C for 10 h is up to 61.34 m²/g. Furthermore, the influence of La2O3 as an additive on the thermal stability was studied and the result showed that such an additive fails to improve the thermal stability of γ-Al2O3.

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Electrowinning of manganese dioxide using Ti-Ru anode from chloride solution

Yin, Wen-Xin (1); Han, Yue-Xin (1); Liu, Yao (2); Shu, Fang-Xia (2)

2007, 28 (6): 855-858. DOI: -

Abstract ( 397 )

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To investigate the new technology for electrowinning of manganese dioxide using Ti-Ru anode from chloride solution, effects of electrolyte temperature, current density and electrolyte composition on current efficiency of MnO2, cell voltage and product quality were examined by aqueous electrolysis with constant electric current. Experimental results indicated that the current efficiency of MnO2 is 96% with cell voltage 2.0 V, MnO2 content 92.32% and the crystal structure of MnO2 in product is γ-MnO2 under the conditions of 75°C, 100 A/m², ρ(Mn²⁺)=50 g/L and ρ(HCl)=10 g/L. Ti-Ru anode for eletrowinning of manganese dioxide from chloride solution was verified available to ensure the product quality up to the standard for electrolytic manganese dioxide and electrolyte temperature is 75°C, lower than that in sulphate solution system (95°C).

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Numerical analysis of loading waveform in SHPB tests of rock-like medium

Zuo, Yu-Jun (1); Tang, Chun-An (1); Zhu, Wan-Cheng (1); Tan, Zhi-Hong (1)

2007, 28 (6): 859-862. DOI: -

Abstract ( 222 )

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Based on mesoscopic damage mechanics, the dynamic numerical code RFPA^2D is developed to simulate the dispersion in wave propagation due to radial inertia effect in large diameter split Hopkinson pressure bar (SHPB), and the influences of waveform such as rectangle stress pulse and triangle stress pulse loaded to incident bar on the dispersion are simulated and analyzed. The results of numerical analysis indicated that the dynamic numerical code RFPA^2D can simulate really the process of stress wave propagation in the pressure bar; when the diameter of SHPB is large, the geometric dispersion effect due to radial inertia become very important; when the appropriate waveform is loaded, the dispersion effect in wave propagation can be reduced, and the triangle wave which may reduce dispersion effect is an appropriate loading waveform in dynamic test of inhomogeneous mediums by using SHPB such as rock and concrete.

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Study on the bio-oxidation process of three single iron sulfide minerals

Yang, Li-Li (1); Yang, Hong-Ying (2); Gong, En-Pu (1); Tong, Lin-Lin (2)

2007, 28 (6): 863-866. DOI: -

Abstract ( 257 )

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There are three iron sulfide minerals involving in gold-bearing ore, which take part in the process of microbial leaching, i.e. pyrite, pyrrhotite and pentlandite in order of gold content. And their bio-oxidation durations are therefore different because of their different distributions in gold-bearing ores. Experimental results showed that all of three minerals produced acidic substance, such as H2SO4. Pyrite is direct oxidized by bacteria and the cell content in solution is less than the other two minerals. Both pyrrhotite and pentlandite are also oxidized by Fe³⁺ besides direct bio-oxidation. Pyrite is more resistant to oxidation than the other two and its durability for oxidation is 3 times as long as that of the other two under the same conditions. It follows that the pyrite-rich gold concentrate should be less used in industrial applications. The bio-oxidation processes of the three single minerals were individually observed and analyzed, and their results can provide important data for reference to microbial leaching practice of complex gold concentrates.

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Lignin content and its activity of key metabolic enzymes in transgenic cotton

Sun, Cai-Xia (1); Chen, Zhen-Hua (2); Miao, Lu (1); Niu, Han-Jie (1)

2007, 28 (6): 867-870. DOI: -

Abstract ( 234 )

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Taking different transgenic cotton as test materials for pot experiment, the lignin content, POD and PAL activities in different cotton tissues were studied to reveal the change of lignin metabolism in transgenic cotton. The results showed that in comparison with non-transgenic cotton, the lignin content, POD and PAL activities in transgenic cotton change somewhat in some varieties, stages and tissues. At squaring stage, the lignin content lowers significantly by 34.96%, 27.15% and 13.22% in Z30 stems, CCRI41 stems and SGK321 leaves, respectively. However, no significant change is found in the total lignin content for all transgenic cotton in experiments.

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Heat-insulating property of mortised modular energy-saving wall

Cao, Guo-Hua (1); Zhu, Fu-Sheng (1); Dong, Feng (1)

2007, 28 (6): 871-874. DOI: -

Abstract ( 174 )

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The mortised modular energy-saving wall is a new heat-insulating system, which can save energy efficiently by holding temperature in the gap between two wallboards. Joint together by mortises and tenons, various inner partition and nonbearing walls can be provided in a modular way. Considered the wall as two-dimension heterogeneity construction enclosure, the average thermal resistance was calculated. Based on the theories of stable heat-transfer of siding, heat-transfer coefficient is discussed, as well as the economical thickness of insulating layer of the new-type wallboard. Calculation and analysis indicated that the heat-transfer coefficient of the new-type wall is 0.689 W/(m²·K) only, far less than that of any other walls. And it means that the new type wall is highly energy-saving. When the polystyrene board thickness is 0.08 m, the wall is most economical with a heat-transfer coefficient down to 0.400 W/(m²·K).

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Experimental investigation on interlayer bonding strength between slurry seal and pavement

Zhang, Jun (1); Zhu, Fu-Sheng (1); Li, Qing-Chang (1)

2007, 28 (6): 875-878. DOI: -

Abstract ( 135 )

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To evaluate the interlayer bonding strength between slurry seal and pavement, an experimental setup was designed on the basis of improved shear tester, with the aim to model well the actual condition of loaded pavements. Experimental result showed that the interlayer bonding strength between the slurry-sealed coat and asphalt-macadam bottom layer decreases with increasing temperature. Taking some different measures to improve interlayer conditions of pavement can affect obviously the bonding strength, such as using asphalt-macadam mixture with big nominal grain size or making the pavement surface coarse by chisel.

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Analysis on multi-echelon inventory delayed ordering control model based on seasonal demand

Ji, Shou-Feng (1); Li, Jia (1); Li, Feng (1); Huang, Xiao-Yuan (1)

2007, 28 (6): 879-882. DOI: -

Abstract ( 241 )

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A multi-echelon inventory system that consists of a DC in central area and lots of retailers and suppliers is considered. To determine the inventory control policy of the DC, a multi-echelon inventory model is required for delayed ordering as a strategy to control the inventory level effectively. It is advocated that the DC and retailers are all controlled by continuous review (R, Q) policies for stock supply in installment; with the constant lead-time for replenishment and retailers when facing to stochastic demands. Under such conditions, the proposed model is developed to determine the reorder points and the ordering quantities for each inventory on the basis of backorder idea. An algorithm example is given to illustrate the possibility of this delayed ordering strategy.

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Coordination model for closed-loop supply chain with product recycling

Qiu, Ruo-Zhen (1); Huang, Xiao-Yuan (1)

2007, 28 (6): 883-886. DOI: -

Abstract ( 424 )

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The coordination of closed-loop supply chain with product recycling in stochastic demand is studied. Two recycling channels covering both manufactures and sellers are considered to develop a Stackelberg game model for closed-loop supply chain where the manufacturers and sellers play the roles of leader and follower, respectively. The Stackelberg equilibrium game is proposed on a basis of decentralized decision which is discussed in relation to centralized decision. The possibility of the existence of a coordinative strategy is also discussed for closed-loop supply chain. A simulation was therefore carried out for the recycling of household electrical appliances as junk. The result showed that a two-part tariff contract signed by both parties can simply make the closed-loop supply chain coordinative so as to ensure that both manufacturers and sellers in the supply chain gain their own rational profits.

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Analysis of model of business cooperation and profit distribution based on windfall profit product under closed-loop supply chain

Zhong, Lei-Gang (1); Qu, Wen-Bo (1); Liu, Xiao-Qin (1); Zhang, Cui-Hua (1)

2007, 28 (6): 887-890. DOI: -

Abstract ( 320 )

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The profitability of each and every business in a supply chain dealing in windfall profit goods relates closely consumer demand, and the service for goods rejection thus becomes one of the main competitive strategies of a business. Profit distribution is not only the basis of the cooperation between businesses in a supply chain, but an incentive. So, aiming at maximizing the gross profit and profit distribution, the cooperative relation between suppliers and retailers in a closed-loop supply chain in random demand and profit sharing among them are modelled. Three main characters of the model considering windfall profit product were derived. A conclusion is drawn that it is reasonable to a certain extent if a business as a node in the supply chain shares the gross profit with others in accordance to its contribution rate to the whole supply chain.

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Existence and multisolvability of sign-inversing solution to nonlinear operator equations and their applications

Sun, Tao (1); Meng, Peng (2); Duan, Xiao-Dong (3)

2007, 28 (6): 891-894. DOI: -

Abstract ( 237 )

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The existence and multisolvability of the sign-inversing solution to nonlinear operator equations are discussed, based on the cone theory and fixed point theory in Banach space. An existence theorem of sign-inversing solution is proved by an upper bound solution, further, the four solutions, i.e. positive, negative, null and sign-inversing solutions, are obtained through an upper bound solution and a lower solution. Then, the existence of both the sign-inversing solution and the four solutions are discussed in detail for a kind of important nonlinear operator equations, i.e. the Sturm-Liouville two-point boundary value problems and, correspondingly the theorems of the existence of both the solutions as above are proved. An example is given to illustrate their applications.

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Fuzzy synthetic evaluation based on pan-integral

Li, Xiao-Qi (1); Song, Shu-Ni (2)

2007, 28 (6): 895-897. DOI: -

Abstract ( 160 )

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Based on the concept of pan-integral defined in fuzzy measure space, the concept of fuzzy evaluation pan-space is given as a derivative. Discussing the common evaluation models and the structure of fuzzy integral, we point out the association between fuzzy synthetic evaluation and pan-integral of which the convergence theorem can play well a basic role in association. In view of that the pan-integral is highly abstract and generalizable, it has good prospects for a wide application in fuzzy synthetic evaluation. Two examples are given showing the practicality of applications.

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Classification of quadratic surfaces in 3D Minkowski space

Yang, Yun (1); Liu, Hui-Li (1); Yu, Yan-Hua (1)

2007, 28 (6): 898-901. DOI: -

Abstract ( 333 )

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Discusses the invariants of quadratic surfaces after they rotate around different coordinate axes then translate parallel in the three dimensional Minkowski space. According to these invariants, the equivalent classes of the quadratic surfaces are defined for classification. It is revealed that in the 3D Minkowski space the transformation of quadratic surface includes around both parallel translation and rotation which comprises space-like and time-like axes within orthogonal frame and that around null-like axes within pseudo-orthogonal frame, where different rotation transformation results in different invariants and classification.

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2007, 28 (6): 902-904. DOI: -

Abstract ( 253 )

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High-temperature storage stability of core-shell rubber particles modified asphalt

Zhang, Bao-Chang (1); Wu, Ming-Jin (2); Gao, Guang-Hui (2); Zhang, Bao-Yan (1)

2007, 28 (6): 905-908. DOI: -

Abstract ( 228 )

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Core-shell PB-g-PS/asphalt is synthesized by grafting styrene and emulsified asphalt onto polybutadiene using the emulsion grafting/polymerizing technology. Then, the core-shell rubber particles are blended with asphalt to modify it with high-temperature storage stability provided. Some properties of the modified asphalt are investigated, such as the differences between the top and bottom layers of modified asphalt at the softening points due to high-temperature segregation, what the differential scanning calorimetric (DSC) analysis shows and the morphologies and homogeneous dispersion of rubber phases in the state of domain network structure In the modified asphalt the number of softening points increases obviously and the temperature difference due to segregation is lower than 1°C. The reaction between asphalt and core-shell rubber particle enables the components which are available to endothermic peak to shift to lower temperature with peak value decreased.

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Structure and non-isothermal crystallization kinetics of syndiotactic 1, 2-polybutadiene

Lu, Jun (1); Hu, Yan-Ming (2); Zhang, Xue-Quan (2); Huang, Bao-Tong (1)

2007, 28 (6): 909-912. DOI: -

Abstract ( 178 )

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Syndiotactic 1, 2-polybutadiene(s-PB) was prepared taking Fe(2-EHA)3/Al(i-Bu)3/DEP as catalyst in hexane at 50°C. Characterized by ¹³C NMR measurement, the contents of 1, 2-structure and syndiotacticity of production are 89.3% and 86.5%, respectively, and the crystallinity is about 68%. Differential scanning calorimetry (DSC) was introduced on relevant non-isothermal crystallization kinetics, and the modified Avrami analysis showed that the Avrami exponent varies from 2.73-3.22 in primary stage, thus indicating that the crystallization behavior of s-PB is a thermal or athermal self-nucleation growing in three-dimensional spherulization. The Ozawa equation was proved that it fails to describe the non-isothermal crystallization process. However, combining the Avrami and Ozawa equations together can describe the non-isothermal crystallization process well, which shows that the exponent a is 1.138, and F(θ) increases with crystallinity. The effective energy barrier was also calculated.

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