The purpose of this research is to determine the sedimentary environment of alluvial terraces south of Khorramabad to Poldokhter using structural elements and limiting SURFACEs. In line with this goal, 4 sections were identified and studied. The cuttings are located at distances between 60 and 80 kilometers south of Khorram Abad towards Poldokhter. The studies conducted on these sections lead to the identification of 10 rock facies, including 4 gravelly rock facies (Gm, Gms, Gp, Gt), 4 sandy rock facies (Sm, Sp, St, Sh) and 2 rock facies. Flower (Fsm, Fm), 13 structural elements including (GB, HS, C/S, LHF, LCS, CVs, DIs, TCS, OF, CH, SB, SHF, LIS) and 6 limiting levels of rank 1 to 6 became. According to rock faces, limiting SURFACEs and structural elements under channel environments, channel bars, point bar, wide cuts (crevasse splay), natural embankments (levee).) and flood plain sub-environment were determined for the alluvial terraces south of Khorramabad to Poldokhtar. Structural elements CH, GB, C/S, LHF, SHF were observed in the studied alluvial barracks in abundance, which indicates a river environment with low twist for the studied alluvial terraces, which alternates between at times, it was attacked by strong and destructive floods, and the coexistence of flood channels indicates that they are periodic.

The present paper is devoted to a new critical state based plasticity model able to predict drained and undrained behaviour of granular material. It incorporates a BOUNDING SURFACE plasticity model describing in multilaminate framework to capitalize on advantages of this mathematical framework. Most of the models developed using stress/strain invariants are not capable of identifying the parameters depending on directional effects such as principal stress rotation and fabric, this is mainly because stress/strain invariants are scalar quantities. The principal features of this model can be postulated as considering both inherent and induced anisotropy, principal stress rotation. Since the local instability of saturated sand within post-liquefaction is highly dependent on the residual inherent/induced anisotropy, bedding plane effects and also the stress/strain path the new mode is competent to be employed in this regard. The constitutive equations of the model are derived within the context of non-linear elastic behaviour for the whole medium and plastic sliding of interfaces of predefined planes. As follows, the constitutive equations are described in detail and then the experimental results and sensitive analysis of key material constants are shown which all imply the power of the model in predicting of soil behaviour under any condition in soil structures.

In this paper, the effect of rotation of principal stress axes on anisotropic strength and deformation behaviors of granular soils has been studied by proposing a new BOUNDING SURFACE plasticity model. Due to incorporation of state parameter into the formulation, the model is capable of considering the effect of soil state over wide ranges of densities and void ratios. Location of critical state line is defined between two boundaries which are those under compression and extension modes of triaxial. Finally the model is evaluated compared with the experimental results obtained from hollow cylindrical apparatus.

Soils in nature can variably be in dry, saturated, or unsaturated conditions. In geotechnical projects, all three soil states must be considered, because soil states can be changed by environmental effects. The most elastoplastic models in soil mechanics were developed for saturated conditions. In this paper, a unified model, in a critical state framework is presented for describing the behavior of a large spectrum of soils under monotonic loading in drained and undrained conditions based on BOUNDING SURFACE theory and the nonassociated flow rule. To unify the simulation of both clayey and sandy soils, among phase transformation behavior, in this model, a modified general dilatancy rule is used. In the current model, an effective stress approach is used that can easily consider both saturated and unsaturated states through effective stress parameter dependent on suction value. The proposed model considered the coupling effect of mechanical and water retention behaviors using soil water characteristic curve dependent on void ratio. To improve model accuracy and convergence, an implicit numerical integration scheme is used to implement the model. Using the experimental data available in the literature, numerical model predictions were shown to be in good agreement with the experimental results. The results showed that the proposed model was able to predict the characteristic features of the behavior of a wide range of soils, including smooth transition behavior from elastic to a plastic state, stress softening and hardening, strain dilatancy, and also phase transformation behavior.

Matrix functions play important roles in various branches of science and engineering. In numerical computations and physical measurements there are several sources of error which significantly affect the main results obtained from solving the problems. This effect also influences the matrix computations. In this paper, we propose some approaches to enclose the matrix functions. We then present some analytical arguments to ensure that the obtained enclosures contain the exact result. Numerical experiments are given to illustrate the performance and effectiveness of the proposed approaches.

Modified Normalized Least Mean Square (MNLMS) algorithm, which is a sign form of NLMS based on set-membership (SM) theory in the class of optimal BOUNDING ellipsoid (OBE) algorithms, requires a priori knowledge of error bounds that is unknown in most applications. In a special but popular case of measurement noise, a simple algorithm has been proposed. With some simulation examples the performance of algorithm is compared with MNLMS.

This paper studies the effect of flexible linear torso on the dynamics of passive quadruped BOUNDING. A reduced-order passive and conservative model with linear flexible torso and springy legs is introduced. The model features extensive spine deformation during high-speed BOUNDING, resembling those observed in a cheetah. Fixed points corresponding to cyclic BOUNDING motions are found and calculated using numerical return map methodologies. Results show that the corresponding robot gaits and the associated performance resemble those of its natural counterparts.