Abstract. Aluminum Lithium alloys are recuperating substantial interest from automotive and aerospace industries owing to their extraordinary specific strength as compared conventional aluminum (2xxx, 6xxx, 7xxx) alloys. The goal of the present investigation is study AA 8090 joints produced with unique solid-state welding technique friction stir (FSW). Tool pin profile induces remarkable influe...

Abstract In this paper, several analytical models are presented for the optimal design of a trapezoidal composite channel cross-section. The objective function is cost per unit length channel, which includes excavation and lining costs. To define system, variables including depth, width, side slopes, freeboard, roughness coefficients were used. constraints include Manning’s equation, flow veloc...

The Khuran Channel, Southern Iran (26°45’N), is a topographically complex channel which is open at both ends. Owning to its particular geometry, this narrow channel is subjected to strong tidal currents.Across-channel distribution of the mean and tidal flows were obtained over a semidiurnal tidal cycle in the Khuran Channel where the highest tidal velocity in the third day of the seco...

Trapezoidal words are finite words having at most n+1 distinct factors of length n, for every n≥ 0. They encompass finite Sturmian words. We distinguish trapezoidal words into two disjoint subsets: open and closed trapezoidal words. A trapezoidal word is closed if its longest repeated prefix has exactly two occurrences in the word, the second one being a suffix of the word. Otherwise it is open...

We establish relationships between the set of trapezoidal intuitionistic fuzzy numbers and the set of interval-valued trapezoidal fuzzy numbers and, on the other hand, between the set of triangular intuitionistic fuzzy numbers and the set of triangular fuzzy numbers. Based on these main results of the paper, the methods or procedures elaborated for interval-valued trapezoidal or triangular fuzz...

Methods for aggregating intuitionistic trapezoidal fuzzy information are investigated. Some operational laws of intuitionistic trapezoidal fuzzy numbers are introduced. Based on these operational laws, some aggregation operators, including intuitionistic trapezoidal fuzzy ordered weighted averaging (ITFOWA) operator and intuitionistic trapezoidal fuzzy hybrid aggregation (ITFHA) operator, are p...

Transfer of debris flow caused by floods in the river downstream of the mountains leads to several damages every year. Numerous researches have been carried out on the Mountain Rivers the results of which show the importance of performing more researches to control debris flows in the floodplain because of various effective hydraulic-geometric parameters.For this purpose, AbNik Mountain River l...