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Wetting hydrological processes are relevant to a considerable number of natural hazards, including landslides, dam breaks, surface runoff after floods, etc. The notable difference between wetting and drying soil–water retention curves (SWRC) has been attributed to the hysteresis phenomenon. Although recent studies confirm enhanced impurity levels of permeating fluid, most modeling approaches simply consider water retention along the drying path and neglect the impurity of pore water. Therefore, the main objective of this paper is to introduce a new water retention model along the wetting path by taking the osmotic potential into account, reflecting the influence of dissolved salts. The new... 

Coupled fluid–solid phase continuum problems associated with large deformation as geotechnics experts encounter in slope stability problems have been extensively reviewed. This has been done with a view to exploring the most efficient numerical approach to solving them for the sake of our environment. Decades ago, analytical solutions known as the limit equilibrium methods (LEM), e.g., Navier–Stokes and the likes were celebrated with the level of mathematical solutions they offered. To overcome the limitations of the LEM in handling more complex slope failure problems, numerical solutions were born, which solved these problems by method of mesh discretization. However, mesh discretization... 

Clayey soils are widely used as barriers to control leachate leakage in landfills. Chemico-osmosis is one of the important phenomena influencing soluble contamination transport through clay barriers acting as a membrane. The membrane ability to restrict contamination transport is referred to as membrane efficiency. Experimental reports have revealed that membrane efficiency is a function of soil void ratio and contamination concentration. However, the currently used empirical function expresses the membrane efficiency simply in terms of average concentration. Therefore, the merit of this study is to enhance the reliability of this function to take into account various concentrations and void... 

Geosynthetic clay liners (GCLs) are synthetic materials manufactured and widely used in geotechnical and geoenvironmental engineering due to their very low permeability and ease of use. As the most critical function of GCLs are their isolating features, it is of primary importance to precisely predict their water retention properties, especially when subjected to impure water having considerable solute concentrations because of landfill leachate. Despite numerous efforts on analytical modeling of bare soil-distilled water retention, less attention has been given to the retention characteristics of GCLs. Therefore, the current study's primary goal is to introduce a new analytical GCL-water... 

A state-of-the-art review has been conducted in this work on soil constitutive modeling, which has emphasized on: soil type, ground-water conditions, loading conditions, structural behavior, constitutive relation discipline, and dimensions. By extension also, the soil constitutive applications were reviewed on the bases of: single discipline dealing with soil mechanical properties constitutive modeling which included slope stability problems, bearing capacity, settlement of foundations, earth pressure problems, soil dynamics, soil structure interaction, thermal and hydrological conditions; bi-discipline (coupled problems) which solve problems related to thermomechanical (freeze/thaw... 

The soil water retention curve (SWRC) or soil–water characteristic curve (SWCC) is a fundamental feature of unsaturated soil that simply shows the relationship between soil suction and water content (in terms of the degree of saturation and volumetric or gravimetric water content). In this study, the applications of the SWRC or SWCC have been extensively reviewed, taking about 403 previously published research studies into consideration. This was achieved on the basis of classification-based problems and application-based problems, which solve the widest array of geotechnical engineering problems relevant to and correlating with SWRC geo-structural behavior. At the end of the exercises, the... 

This study proposes a new approach to incorporate motion duration in incremental dynamic assessments. In the proposed methodology, at each intensity level, a simulation-based approach which is verified with actual data is employed to determine the median duration and the median acceleration spectra of ground motions expected to occur at the site. Afterward, at each intensity level, artificial or spectrally matched motions are produced based on the median acceleration spectra and the median duration, indicating that different intensity levels are directly covered by the generated artificial or adjusted motions rather than just scaling up and down a set of recorded ground motions. In the... 

A tailings dam is normally constructed through self-consolidation with minimum compaction effort. Accordingly, special attention to the ultimate limit design in assessing the tailings dam instability condition is of primary importance. Furthermore, the existence of pore fluid chemical contaminants with high concentrations makes soil hydraulic and shear resistance properties subject to considerable changes.Therefore, this study aims to investigate the stability of a tailing dam using saturated-unsaturated flow analysis under 0.2 and 0.6 M sodium chloride solutions and pure water as a benchmark. To make the analyses as realistic as possible, recently developed solute-dependent hydraulic... 

In this work, phosphorus-31 and aluminum-27 nuclear magnetic resonance techniques were used to characterize the distribution of soluble aluminophosphate species in methanol + water and ethanol + water mixtures. The assignment of the peaks to alu-minate species was attempted, clarifying earlier work and producing information on the different aluminophosphate complexes. Nine peaks were observed at -0.41, -6.4, -7.5, -7.9, -13.1, -13.9, -16.6, -18.1 and -20.6 ppm. Four new peaks appeared in the 31P NMR spectra of the alcoholic aluminophosphate solutions and their intensities changed with changes of the alcohol:water volume ratio. These new peaks were observed in the presence of methanol or... 

This paper presents some approaches based on data mining techniques to solve the prediction task of Computational Intelligence and Learning (CoIL) Challenge 2000. The prediction task of the contest is a direct mailing problem and the goal is to improve its response rate. The main issue in this competition is the incompatibility of the dataset in which the distribution of the classes of the target attribute is highly unbalanced. This in turn causes high error rate in identifying the minority class samples. Three different level methods including data-level, algorithm-level, and hybrid method are used to overcome this issue. The specificity, sensitivity, precision-recall, and ROC criteria are... 

Direct marketing identifies customers who buy, more probable, a specific product to reduce the cost and increase the response rate of a marketing campaign. The advancement of technology in the current era makes the data collection process easy. Hence, a large number of customer data can be stored in companies where they can be employed to solve the direct marketing problem. In this paper, a novel Bayesian method titled correlation-augment naïve Bayes (CAN) is proposed to improve the conventional naïve Bayes (NB) classifier. The performance of the proposed method in terms of the response rate is evaluated and compared to several well-known Bayesian networks and other well-known classifiers... 

Land subsidence, as a gradual settling of the ground surface, has become a threatening hazard to many infrastructures and lifelines. Among them, electricity dispatch centers (EDC) are considered the heart of a typical power transmission system, closely related to both domestic and industrial aspects of society. Therefore, this study aims to systematically explore early warnings and damages imposed on EDCs in Tehran. A combination of field reconnaissance and InSAR time series analyses are adopted to correlate subsidence-induced damages with several triggering mechanisms, such as the dynamic effects of subways and extra groundwater exploitation. Accordingly, spatially- and... 

In this paper a web based production system is proposed. This system consists of a web services agent to manage the receipt the order from the customer, a price agent to predict the price of the product for the customer, a decision agent to build up a virtual enterprise to manufacture and deliver of the product to the customer and make essential decisions of the system and a design and control agent to do the engineering tasks related to the production process of the product. This structure provides the production system with a high level of agility and flexibility. © 2019 IEEE