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In this paper, Lorenz chaotic system with stochastic perturbation and unknown parameters is investigated, in which the stochastic perturbations is one-dimensional random process of the standard Wiener. Based on stochastic Lyapunov stability theory, It formula and adaptive control method combined with three adaptive control laws and two adaptive control laws respectively, two mean square Asymptotic adaptive synchronization standards are put forward theoretically. These new standards are in a simple form and easy to deal with. Moreover, with these standards, not only drive system with stochastic perturbations can be synchronized with the respond system, but also unknown parameters in the system can be identified. Finally, the Matlab numerical simulations confirm that the proposed results are correct and effective.

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Pulsed gas metal arc weld (GMAW) was widely used for the advantages of controllable heat input, all-position welding, and no spatter. In order to obtain an ideal welding process, the stability of the arc length was studied in many researches, but the influence of arc length on the properties of weld metal was ignored. In this paper, the effect of arc length on oxygen content and mechanical properties of weld metal during pulsed GMAW was studied. Q690 high strength steel was selected as the base metal, and ER69-G solid wire, with a diameter of 1.2 mm, was used as the electrode wire. Additionally, the shielding gas and the wire feed rate were 82% Ar + 18% CO2 and 4 m/min, respectively. The results showed that as the arc length raised from 2.9 mm to 9.2 mm, the oxidation reacted more completely in the droplet transfer zone, and the oxygen content of the weld metal increased significantly. The tensile strength of the weld metal reduced but the −40 °C impact energy heightened. Due to the longer arc, the proportion of acicular ferrite (AF) in the microstructure decreased, but the proportion of lath bainite (LB) and granular bainite (GB) decreased. The higher oxygen content of weld metal was useful for the formation of inclusions, which promoted the nucleation of acicular ferrite and dimples, contributing to the growth of plasticity and toughness of weld metal.

The effects of adhesion promoters, cobalt decanoate and PN759 (modified resorcinol) on the static and dynamic adhesion properties of rubber/steel cord in a carcass recipe are examined. A new testing method with special rubber/steel cord specimens was developed. It was found that cobalt decanoate could improve the static adhesion and favored the dynamic adhesion of rubber/steel cord so that adhesive failure mainly occurred in rubber phase. A resorcinol‐formaldehyde‐silica promoting system was deleterious to adhesion stability, but improved initial adhesion strength. PN759 improved the dynamic mechanical properties compared with resorcinol for the carcass vulcanizates at strains less than 10%. PN759 instead of resorcinol slightly improved the static and dynamic adhesion and the probability that adhesion failure occurred in the interphase was similar to that occurring in the rubber phase. The dynamic “pull‐out forces” for samples with 1.0 phr cobalt decanoate first increased and then decreased with the increase in the number of fatigue cycles and reached a maximum at 100,000 fatigue cycles. The covered rubber on the “pulled‐out” cord after fatigue appeared to form a screw thread form and the greater pull‐out force corresponded to more uniform and narrower screw threads. SEM images indicated that un‐dispersed filler agglomerates could be the initiating factor for adhesive failure. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39460.