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The structure of a bridge has certain peculiarities, and its pile foundations are susceptible to uplift or settlement deformation due to various factors. This can result in bridge deck cracking, structural instability, tilting, and even irreversible damage, which significantly impacts the bridge's stability and driving safety. This study focuses on the Shiyangtai No.1 Bridge and aims to investigate the factors that cause abnormal rise and fall deformations of bridge pile foundations. The study combines macro and micro analysis, physical characteristic testing of the overlying soil under the bridge pile foundation, and numerical simulation of the bridge pile foundation in the goaf. The study discusses in-depth the formation mechanism of the abnormal uplift of some pile foundations of the Shiyangtai No.1 Bridge based on the analysis of the factors influencing the abnormal rise and fall deformation of the bridge pile foundations at home and abroad. The expansive soil beneath the pile foundation is weak, and the force generated by the water expansion is insufficient to cause the pile foundation to rise to 309 mm. The results indicate that the pile foundation of the bridge is not affected by the expansion characteristics of the overlying soil. The collapse of the goaf roof generates double lateral thrust from the accumulation body at the bottom of the goaf and the upper collapse arch. This causes staggered bending uplift of the sandstone soil layer, resulting in upward squeezing pressure that causes the bridge pile foundation to rise. Therefore, the coal mining area is the main factor influencing the abnormal uplift of the pile foundation of the Shiyangtai No.1 Bridge. [ABSTRACT FROM AUTHOR]

It is often difficult to predict the optimal neural network size for a particular application. Constructive or destructive methods that add or subtract neurons, layers, connections, etc. might offer a solution to this problem. We prove that one method, recurrent cascade correlation, due to its topology, has fundamental limitations in representation and thus in its learning capabilities. It cannot represent with monotone (i.e., sigmoid) and hard-threshold activation functions certain finite state automata. We give a 'preliminary' approach on how to get around these limitations by devising a simple constructive training method that adds neurons during training while still preserving the powerful fully-recurrent structure. We illustrate this approach by simulations which learn many examples of regular grammars that the recurrent cascade correlation method is unable to learn.

This paper reports mineral and whole‐rock geochemical data (major and trace elements, Sr–Nd isotopes, and in situ plagioclase Sr‐isotope analysis) for Cenozoic volcanic rocks from Sabeto, NW Fiji, with the aim of constraining the origin of Cenozoic shoshonitic rocks found throughout Fiji. The most mafic shoshonitic lavas (absarokites) exhibit porphyritic textures and massive structure with phenocrysts of olivine (Fo = 76–78), clinopyroxene (Mg# = 73.9–80.0), and plagioclase (An = 71.9–92.1). Major element geochemical data include SiO2 = 47.31–48.46 wt%, MgO = 4.20–5.76 wt%, Mg# = 49–51, Al2O3 = 17.64–18.93 wt%, and (Na2O + K2O) = 5.12–7.01 wt%. The trace element geochemistry is typically arc like, with enrichment in the large ion lithophile elements (LILEs), the light rare earth elements (LREEs), and P, along with depletion in the heavy rare earth elements (HREEs) and high‐field‐strength elements (HFSEs; e.g., Nb, Ta, Zr, Hf, and Ti). Whole‐rock (87Sr/86Sr)i ratios and εNd(t) values vary from 0.7037 to 0.7039 and from +7.62 to +8.45, respectively. The former is near equal to the 87Sr/86Sr ratios of plagioclase phenocrysts (0.7034–07039). Based on these geochemical data and the results of previous studies, we propose that the Sabeto shoshonitic primary magma was derived from partial melting of the depleted lithospheric mantle, modified by subduction‐related fluids. The thermobarometric calculation indicates that the P–T conditions of Fiji shoshonitic magma chamber are ~1100 °C and ~2.8 GPa (~90 km depth), with an average H2O fraction of ~6 wt%. In addition, the shoshonitic melts experienced fractional crystallization of clinopyroxene, olivine, and plagioclase during magma evolution. These volcanic rocks formed in an extensional setting following collision of the Vitiaz arc and the Ontong Java Plateau during the Pliocene. [ABSTRACT FROM AUTHOR]

In primates, grooming is considered among the most common behaviors for maintaining social bonds; however, to date, few studies have examined grooming behavior in gibbon species in detail. We used both a 5-min interval scan method and social network analysis to study grooming in two groups of polygynous western black-crested gibbon ( Nomascus concolor) in Wuliang Mountain, Central Yunnan, China. Individuals in both groups spent little time in social grooming (1.45% and 1.97% of active time). We compared the two groups' grooming networks and found that the group that maintained a more stable social unit had a more complex grooming network while the group with new immigrants had a grooming network characterized by fewer grooming pairs. Females in both groups played important roles in the grooming network. A newly immigrant female spent the most time grooming others and chose the resident adult female as her main adult grooming partner. Other females from both groups chose the adult male as their primary grooming partner (except their offspring). A sub-adult male who had resided in his natal group for 2 years after maturing into an adult also groomed more and was at the center of the network. This male finally replaced the breeding male in his group 3 years after our data collection period ended. We hypothesize that the immigrant female and the resident young adult male engaged in more extensive grooming interactions as a behavioral strategy to gain tolerance from long-term residents. Our results suggest that female gibbons in polygynous groups actively cooperate in maintaining social relationships rather than co-exist through tolerance or avoidance. Our observations indicate that grooming networks in crested gibbons reflect individual dynamics and partly support the social cohesion hypothesis for primate grooming. In this regard, we suggest that changes in gibbon grooming networks can be used to predict social change. Am. J. Primatol. 75:1165-1173, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A relaxation model employing double adiabatic magnetohydrodynamics (MHD) is introduced. In this model the neglect of heat flux in the Chew-Goldberger-Low (CGL) equations is treated by considering a very special class of the entropy invariants. The equilibria have uniform temperatures T[sub ⊥] and T[sub ], nearly uniform A ≡ j[sub ]/B = μ/σ, where σ is the local firehose parameter, and p = p (B). The density profile is not uniform (unless T[sub ⊥] = T[sub ]), in qualitative agreement with experiments. The equilibria are shown to be linearly stable, in spite of "bad" curvature, if the firehose and mirror parameters are positive and if the parallel current is not too large. A nonlinear stability criterion involving modified firehose and mirror parameters, and based upon the so-called energy-Casimir method, is also derived. [ABSTRACT FROM AUTHOR]

The self-focusing of relativistically intense laser light pulses is analyzed, where the pulse length is short enough that ion inertia prevents any significant motion of ions. Self-focusing occurs as a result of an increase of the wave refractive index arising from two effects: the mass increase of electrons caused by their relativistic quiver velocity in the light wave, and the reduction of the electron density as a result of ponderomotive force expulsion of the electrons. The latter effect is significant even for rather small values of (P-PL)/PL, where P is the laser beam power and PL is the critical power above which self-focusing occurs. In fact, for (P-PL)/PL>=0.1 the effect is so strong that all electrons are expelled within a core radial region of the self-focused laser light channel (this new phenomenon is called electron cavitation). [ABSTRACT FROM AUTHOR]

Previous work on the cubic direct interaction approximation applied to the truncated (in Fourier space) cubically nonlinear Schrödinger equation model of Langmuir turbulence is extended to more modes. In the undriven, undamped case, excellent agreement between the statistical theory and a numerical ensemble of solutions of the dynamic equations is obtained. In the driven, damped case, satisfactory agreement is obtained provided the dynamic ensemble is limited to initial conditions in the basin of attraction. [ABSTRACT FROM AUTHOR]

The cubic direct interaction approximation is applied to a truncated (in Fourier space) version of the cubically nonlinear Schrödinger equation model of Langmuir physics. The results are compared (in the three-mode case) to those for an ensemble of numerical solutions of the dynamical equations with 10000 different sets of Gaussianly distributed initial conditions. In the undriven, undamped case, the statistical theory (but not the ensemble) evolves to a state of thermal equilibrium. In the driven, damped case, the statistical theory appears to evolve to a state close to that corresponding to one of the limit cycles of the dynamical equations. [ABSTRACT FROM AUTHOR]