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In this paper, we devote to the investigation of passivity in two types of coupled stochastic neural networks (CSNNs) with multiweights and incompatible input and output dimensions. First, some new definitions of passivity are proposed for stochastic systems that may have incompatible input and output dimensions. By utilizing stochastic analysis techniques and Lyapunov functional method, several sufficient conditions are respectively developed for ensuring that CSNNs without and with multiple delay couplings can realize passivity. Besides, the synchronization criteria for CSNNs with multiweights are established by employing the results of output-strictly passivity. Finally, two simulation examples are given to illustrate the validity of the theoretical results.

Purpose This paper aims to present a multi-scale stochastic damage model (SDM) for concrete and apply it to the stochastic response analysis of reinforced concrete shear wall structures. Design/methodology/approach The proposed SDM is constructed at two scales, i.e. the macro-scale and the micro-scale. The general framework of the SDM is established on the basis of the continuum damage mechanics (CDM) at the macro-scale, whereas the detailed damage evolution is determined through a parallel fiber buddle model at the micro-scale. The parallel buddle model is made up of micro-elements with stochastic fracture strains, and a one-dimensional random field is assumed for the fracture strain distribution. To represent the random field, a random functional method is adopted to quantify the stochastic damage evolution process with only two variables; thus, the numerical efficiency is greatly enhanced. Meanwhile, the probability density evolution method (PDEM) is introduced for the structural stochastic response analysis. Findings By combing the SDM and PDEM, the probabilistic analysis of a shear wall structure is performed. The mean value, standard deviation and the probability density function of the shear wall responses, e.g., shear capacity, accumulated energy consumption and damage evolution, are obtained. Originality/value It is noted that the proposed method can reflect the influences of randomness from material level to structural level, and is efficient for stochastic response determination of shear wall structures.

The Keketale is the largest Pb–Zn deposit in the volcano-sedimentary Maizi Basin of the South Altay Orogenic Belt (AOB), Northwest China. The stratabound orebodies are hosted in a suite of meta-sedimentary rocks intercalated with volcanic rocks of the Lower Devonian Kangbutiebao Formation. The massive and banded ores representing the main mineralization stage are relatively well-preserved in the ore district. This paper reports systematic geochronological results including the zircon laser ablation–multiple collector–inductively coupled plasma–mass spectrometry (LA-MC-ICP-MS) U–Pb analyses on two meta-felsic volcanic rocks from the Kangbutiebao Formation and Rb–Sr isotope dating on seven sphalerite samples from the main mineralization stage, together with some sulphur isotopic data to constrain the mineralization age and the genesis of the deposit. Rb–Sr isotope dating yield an isochron age of 398.2 ± 3.3 Ma generally synchronous with the zircon (LA-MC-ICP-MS) U–Pb analyses of a meta-rhyolite and a meta-dacite from the strata (410.5 ± 1.3 Ma and 394.8 ± 1.9 Ma, respectively). The δ34S values of seven pyrite samples in the main massive and banded ores vary from −12.4‰ to −6.2‰, indicating that the main ore-forming sulphur of the deposit was derived from bacterial reduction of seawater sulphate. By integrating the field, chronological, and isotopic evidences, we conclude that the Keketale Pb–Zn deposit is a VMS-type deposit. Combining our results with the isotopic geochronology in the South AOB, we argue that the South AOB has undergone three mineralization episodes: the syndepositional mineralization (412–387 Ma), the subvolcanic hydrothermal-related mineralization (382–379 Ma), and the epigenetic mineralization that is genetically linked to regional metamorphism and deformation (260–204 Ma). The Keketale Pb–Zn deposit is a product of the Devonian seafloor hydrothermal exhalation system in the South AOB.

Ahstract- This paper concerns the properties analysis and motion planning for an underactuated wheeled Acrobot (WAcrobot). First, an input relationship is constructed based on the structural characteristics of the WAcrobot system, which changes the system into a nonlinear cascade system. And the dynamic properties of the cascade system are analyzed. After that, the properties and a reverse motion idea are used to design a motion trajectory for the WAcrobot in its whole motion space. The trajectory starts from a stable equilibrium point and ends at an unstable equilibrium point of the system. Tracking the trajectory enables the swing-up and stabilization control objective of the WAcrobot to be achieved. Finally, a numerical example demonstrates the effectiveness of our presented theoretical results.

The Jilongshan skarn Cu–Au deposit is located at the Jiurui ore cluster region in the southwestern part of the Middle–Lower Yangtze River valley metallogenic belt. The region is characterized by NW-, NNW- and EW-trending faults and the mineralization occurs at the contact of lower Triassic carbonate rocks and Jurassic granodiorite porphyry intrusions. The intrusives are characterized by SiO2, K2O, and Na2O concentrations ranging from 61.66 to 67.8 wt.%, 3.29 to 5.65 wt.%, and 2.83 to 3.9 wt.%, respectively. Their A/CNK (A/CNK = n(Al2O3)/[n(CaO) + n(Na2O) + n(K2O)]) ratio, δEu, and δCe vary from 0.77 to 1.17, 0.86 to 1, and 0.88 to 0.96, respectively. The rocks show enrichment in light rare earth elements ((La/Yb)N = 7.61–12.94) and large ion lithophile elements (LILE), and depletion in high field strength elements (HFSE), such as Zr, Ti. They also display a peraluminous, high-K calc-alkaline signature typical of intrusives associated with skarn and porphyry Cu–Au–Mo polymetallic deposits. Laser ablation inductively coupled plasma spectrometry (LA-ICP-MS) zircon U–Pb age indicates that the granodiorite porphyry formed at 151.75 ± 0.70 Ma. A few inherited zircons with older ages (677 ± 10 Ma, 848 ± 11 Ma, 2645 ± 38 Ma, and 3411 ± 36 Ma) suggest the existence of an Archaean basement beneath the Middle–Lower Yangtze River region. The temperature of crystallization of the porphyry estimated from zircon thermometer ranges from 744.3 °C to 751.5 °C, and 634.04 °C to 823.8 °C. Molybdenite Re–Os dating shows that the Jilongshan deposit formed at 150.79 ± 0.82 Ma. The metallogeny and magmatism are correlated to mantle–crust interaction, associated with the subduction of the Pacific Plate from the east. Copyright © 2013 John Wiley & Sons, Ltd.

Double-sided double arc welding (DSDAW), a high efficiency method for welding thick plate of low alloy high strength steel which does not require back chipping is used in this paper, research on multi-pass route planning for thick plate of low alloy high strength plate by double-sided double arc welding. Firstly, establish a double-sided double arc welding system that can realize thick plate of low alloy high strength steel double-sided double arc welding by double robots. Then, Propose the multi-pass route planning for thick plate of low alloy high strength steel by double-sided double arc welding by means of misplaced welding. According to the welding parameters and the geometry size of groove, plan the layers, the number of beads and the concrete position of the welding torch for each bead. Finally, the welding experiment has been done to verify the effectiveness of multi-pass route planning. The results of welding experiment are approximately agreement with the multi-pass route planning results. The backing weld can get better appearance in the front and guarantee fusion penetration in the back simultaneously. On the basis of the multi-pass welding route planning, good fusion and leveling interface can be obtained after filler passes.

Jilongshan Au-Cu deposit is a typical skarn deposit in the southeastern Hubei metallographic province of the Middle-Lower Yangtze River Fe-Cu metallogenic belt. But little study of ore-forming material source has been made in Jilongshan Au-Cu deposit. Therefore, we discussed the ore-forming material source by analyzing 15 lead geochemistry samples collected in Jilongshan deposit. The ranges of the Pb isotopic compositions are from 17.358 to 18.589 for 206Pb/204Pb, 15.414 to 15.745 for 207Pb/204Pb and 37.956 to 39.094 for 208Pb/204Pb, which are anomalous and their single-stage model ages cannot be used as a criterion for metallogenic epoch. However, the distributing characteristics of the single-stage model ages suggest that the ore Pb have mixing sources. The linear distribution of Pb isotope in tectonic model diagram suggests that the consistent relation of granodiorite porphyry, skarn, marble and ore, which is also a good proof that the ore-forming materials are partly from magma.