Advanced Materials Research Vols. 179-180

Abstract: The cascade compensation algorithm for no damp strapdown inertial navigation system (SINS) is designed based on control model and error characteristic of SINS level-loop. According to stability and frequency characteristic analysis for SINS level-loop, a compensation network, which is chosen to alter either the roots location or the frequency response of the system, is cascaded with the SINS level-loop to damp the oscillatory or accumulated errors. The network parameters are attained by designing the frequency characteristic using frequency domain performance indexes, which are transformed from the expected time domain indexes. The algorithm implementation of the compensator is competed by solving the first-order differential equations set, which is derived from Laplace transform of the compensation network using intermediate variables. Results of digital simulation and test on sea proved that the system attitude accuracy improved 1 order and the system position accuracy improved 1 time when the compensation network was cascaded into SINS.

Abstract: The traditional KNN algorithm usually adopts European distance formula to measure the distance between two samples. Since each attribute functions differently in the actual sample data collection, the accuracy of the classification will be reduced consequently, this article proposes one method to measure the attribute value and entropy weight, namely KNN algorithm based on weighted entropy of attribute value. The experiment indicated that, compared with the traditional KNN algorithm, the algorithm proposed in this article can not only guarantee the efficiency of classification but also enhance the accuracy of classification.

Abstract: When a certain distributed attack spreads in network, network hosts are classified into three types. The first type has undergone the distributed attack. The second type has the attacked likelihood. The third type is immune to the distributed attack. Distributed attack will cause congested links in network usually. Network security situation of distributed attack can be determined by attack severity degree of hosts and congestion condition of network. The paper analyzes distributed attack spread and builds an attack graph. The attack graph is used to reflect attacked status of hosts and congestion degree of network. Network security situation is deduced based on the graph.

Abstract: An image information extraction algorithm on fractional differentials is put forward in this paper that is based on the characteristics of fractional differential in signal processing. This paper has extracted the information of salt and pepper noise images with various coefficients, and analyzed and compared it with the information extraction results of classic integer-order operators as Prewitt, Roberts and Sobel. Experiments have shown that not only the high-frequency marginal information can be extracted by extracting information with fractional differentials, just as it is extracted with integer-order operators, but the texture information can also be extracted from the smooth region. Besides, this algorithm is featured with great noise immunity against salt and pepper noises.

Abstract: Damage severity identification is an important content among structural damage identification. In order to avoid the disadvantages of conventional BPNN, a modified BP neural network was proposed to identify structural damage severity in this paper. The modified BPNN was trained by using structural modal frequency qua BPNN input, and then used to forecast structural damage severity. Finally, the results of simulation experiment of composite material cantilever girder show that the improved method is very effective for damage severity identification and possess great applied foreground.

Abstract: Driving intentions can not intervene in the shift curve according to the change rate of throttle opening and road information. Considered the change rate of throttle opening and road information, the fuzzy control method was used to amend the economic conditions of the shift curve. The results show that the fuzzy control method adding driving intention can amend shift curve of the economic conditions and taking into account economic and power performance requirements, in line with the driving intentions to operate shift curve in accordance with the road information.

Abstract: The system model of flexible suspension bridge under several moving loads was founded according to SD oscillator with time –dependent stiffness. The model was simulated by the software MATLAB and the nonlinear dynamic behaviors of the system with different velocities were analyzed. Bifurcation diagram of the system is obtained with the changing of vehicle speed; meanwhile the phase trajectories and the Poincaré sections are also presented. The result shows the complicated nonlinear dynamics with periodic motion, quasi-periodic phenomena and chaos, the occurrence alternatively among these quasi-period and chaos, which reveals the reason that causes the S-shape deformation of flexible suspension bridge under moving load easily.

Abstract: The processing technique of bamboo particle board using laccase-treated calcium lignosulfonate was investigated and optimized. We studied the influence of enzyme amount, calcium ligosulfonate amount and hot pressing temperature on different particle board properties. All three factors were significant difference at different levels. There has significant differences between enzyme amount and Modulus of Rupture (MOR)，Modulus of Elasticity (MOE), Thickness Swelling (TS) (P<0.01)and Internal Bonding Strength (IB) (P<0.1). There has significant differences between Calcium lignosulfonate amount and MOR，TS(P<0.01), IB(P<0.05) and MOE (P<0.1). There has significant differences between hot pressing temperature and MOE，TS(P<0.01) and IB(P<0.1), but no significant differences on MOR. The optimum condition for board making as follows: enzyme amount 50u•g-1，calcium lignosulfonate amount 10%，hot pressing pressure 3.0MPa， 200°C and 7min while 0.75g•cm-3 board density and 10 mm thickness.

Abstract: In recent years, with the quick development of domestic automobile industry, the after market’s demand is demonstrating strong progress. However, due to lack of customer quick responsive system of after-sale service logistics, quite a few enterprises suffer from gradual loss of profit and customer resource. The article summarize the as-is status for time-efficiency management of after sale logistics, explaining the driving factor of current issues, i.e., task oriented current system, capacity constraint of logistics activities, lack of customer time efficiency evaluation and blank of after sale logistics operation staff. Based on these, together with investigation of companies, bring forward the mechanism of time-efficiency oriented after-sale logistics operation. This mechanism consists of eight sub-systems: organization structure, network planning and layout, reverse logistics operation procedure, time window evaluation mechanism, automatic replenishment system, reverse forecasting system, Kan-ban message system as well as disposal & reuse system. Furthermore, the article makes analysis of the internal operations and external relevance of these eight sub-systems.

Abstract: In this paper, one kind of low density SMC has been introduced. Hollow-glass micro-spheres has been added into common SMC(Sheet Moulding Compound) to reduce the density, as well as the cost. Properties testing of SMC were conducted according to the National standards. Results showed that most of the indexes of the low density SMC are lower than that of common SMC with varying degrees of decline. Products were prepared by mould pressing. The weight of low density SMC product is decline by 17.3%. Some properties, such as medium resistance, vibration endurance, fatigue endurance, stiffness and strength, have been investigated in detail. Experimental and performance testing results showed that this kind of low density SMC is suitable for the automotive application.