A Monte-Carlo game theoretic approach for Multi-Criteria Decision Making under uncertainty

Game theory provides a useful framework for studying Multi-Criteria Decision Making problems. This paper suggests modeling Multi-Criteria Decision Making problems as strategic games and solving them using non-cooperative game theory concepts. The suggested method can be used to prescribe non-dominated solutions and also can be used as a method to predict the outcome of a decision making problem. Non-cooperative stability definitions for solving the games allow consideration of non-cooperative behaviors, often neglected by other methods which assume perfect cooperation among decision makers. To deal with the uncertainty in input variables a Monte-Carlo Game Theory (MCGT) approach is suggested which maps the stochastic problem into many deterministic strategic games. The games are solved using non-cooperative stability definitions and the results include possible effects of uncertainty in input variables on outcomes. The method can handle multi-criteria multi-decision-maker problems with uncertainty. The suggested method does not require criteria weighting, developing a compound decision objective, and accurate quantitative (cardinal) information as it simplifies the decision analysis by solving problems based on qualitative (ordinal) information, reducing the computational burden substantially. The MCGT method is applied to analyze California’s Sacramento-San Joaquin Delta problem. The suggested method provides insights, identifies non-dominated alternatives, and predicts likely decision outcomes.     

Topology optimization of shear wall structures under seismic loading

A topology optimization formulation is developed to find the stiffest structure with desirable material distribution subjected to seismic loads. Finite element models of the structures are generated and the optimality criteria method is modified using a simple penalty approach and introducing fictitious strain energy to simultaneously consider both material volume and displacement constraints. Different types of shear walls with/without opening are investigated. Additionally, the effects of shear wall-frame interaction for single and coupled shear walls are studied. Gravity and seismic loads are applied to the shear walls so that the definitions provide a practical approach for locating the critical parts of these structures. The results suggest new viewpoints for architectural and structural engineering for placement of openings.     

Geochemical and hydrogeochemical evolution of groundwater in Ferdows area, northeast of Iran

The chemical analysis of 19 water wells in Ferdows area, Northeastern Iran, has been evaluated to determine the hydrogeochemical processes and ion concentration background in the region. In the study area, the order of cation and anion abundance is Na⁺ > Ca²⁺ > Mg²⁺ > K⁺ and Cl^? > SO ₄ ^?2  > HCO₃ ^? > NO₃ ^?, respectively, and the dominating hydrochemical types are Na–Cl. Most metal concentrations in water depend on the mineral solubility, and pH, Eh, and salinity of the solution. Their ΣREE concentrations showed excellent correlations with parameters such as TDS and pH. North American Shale Composite (NASC)-normalized REE patterns are enriched in the HREEs relative to the LREEs for all groundwaters. They all have positive Eu anomalies (Eu/Eu* = 0.752–3.934) and slightly negative Ce anomalies (Ce/Ce* = 0.019–1.057). Reduction–oxidation, complexation, desorption, and re-adsorption alter groundwater REE concentrations and fractionation patterns. The positive Eu anomalies in groundwaters are probably due to preferential mobilization of Eu²⁺ relative to the trivalent REEs in the reducing condition.     

Investigation on the effect of inclined crest step pool on scouring protection in erodible river beds

Natural Hazards - One of the aquatic structures that are used for protect water channels against bed erosion is serial step-pool. These steps similarity of the vertical drops structure are exposed...     

Failure Behavior of Room and Pillar with Different Room Configuration Under Uniaxial Loading Using Experimental Test and Numerical Simulation

Geotechnical and Geological Engineering - This paper investigates different configuration of the room and pillar under uniaxial loading using experimental and particle flow code in two dimension...     

Regionalization of precipitation characteristics in Iran’s Lake Urmia basin

Theoretical and Applied Climatology - Lake Urmia in northwest Iran, once one of the largest hypersaline lakes in the world, has shrunk by almost 90% in area and 80% in volume during the last four...     

Hydrogeochemical investigation using multivariate analytical methods in Esfadan basin,eastern Iran

The chemical analyses of 71 water-supply wells in the Esfadan area of eastern Iran were evaluated using statistical methods to determine the hydrogeochemical processes that control groundwater quality. Groundwater in the study area is mainly saline (Na–Cl type water), and statistical analyses show that there are three subgroups of groundwater quality, whose differences reflect the influences of geology.     

Heavy metal accumulation in soil after application of organic wastes

Municipal solid waste compost and cattle manure are used as organic fertilizers in agriculture and horticulture. These wastes, however, may also have some negative effects on the agricultural environment. This study investigates the effects of municipal solid waste compost of Kerman (MSC) and cattle manure (CM) on availability of the heavy metal in calcareous soil (extractable with EDTA) in greenhouse conditions. The MSC and CM were mixed thoroughly with soil at rates of 0%, 2%, and 4% of dry matter. After 90 days of incubation, the soil samples were analyzed. Addition of levels of each two organic wastes into soil significantly decreased the soil pH and increased the soil EC as compared with control (unamended soil).The available contents (EDTA-extractable) of Cd, Pb, Cu, Zn, and Cu in the soil samples were increased because of each two organic treatments applied. The heavy metal contents in the soil samples amended with MSC were more than CM. The heavy metal contents of organic wastes were well below the maximum allowed by USEPA. It is recommended that in Iran, the legal maximum permissible limit for heavy elements in organic wastes must be determined.     

Estimation of uniaxial compressive strength based on P-wave and Schmidt hammer rebound using statistical method

Preparing high-quality samples, which can fulfill testing standards, from weak and block-in-matrix conglomerate for laboratory tests, is a big challenge in engineering projects. Hence, using indirect methods seems to be indispensable for determination uniaxial compressive strength (UCS). The main objective of this study is to estimate the relation between sonic velocity (Vp), Schmidt hammer rebound number (SCH) and UCS. For this reason, some samples of weak conglomeratic rock were collected from two different sites of dam in Iran (Bakhtiari and Hezardareh Formations). In order to evaluate the correlation, the measured and predicted values utilizing simple and multivariate regression techniques were examined. To control the performance of the proposed equation, root mean square error (RMSE) and value accounts for (VAF%) were determined. The VAF% and RMSE indices were computed as 94.34 and 1.56 for the relation between Vp and UCS from simple regression model. These were 94.39 and 1.6 between SCH and UCS, while these were 97.24 and 1.34 for uniaxial compressive strengths obtained from multivariate regression model.