An efficient binary chaotic symbiotic organisms search algorithm approaches for feature selection problems

The Journal of Supercomputing - Feature selection is one of the main steps in preprocessing data in machine learning, and its goal is to reduce features by removing additional and noisy features....     

Modeling the Exogenous Coordination of Mobile Channel-based Systems with Petri Nets

In this paper, we discuss how to model systems that communicate through and are coordinated by mobile channels. Mainly, we focus on modeling the exogenous coordination behavior imposed by these channels. We use Petri Nets as our modeling language, for they provide a graphically and mathematically founded modeling formalism. We give Petri Nets for a set of mobile channel types. This allows us to construct models of applications, by taking the Petri Net of each component and each mobile channel, and composing them together. For this purpose, we define a special Petri Net composition function. We also discuss analysis and simulation of these models and their exogenous coordination behavior.     

Synthesis and analysis of a new class of six-degree-of-freedom parallel minimanipulators

A new class of 6-degree-of-freedom (dof) parallel minimanipulators is introduced. The minimanipulators are designed to provide high resolution and high stiffness for fine position and force control in a hybrid serial-parallel manipulator system. Two-dof planar linkages and inextensible limbs are used to improve positional resolution and stiffness of the minimanipulators. The 2-dof linkages serve as drivers for the minimanipulators. The minimanipulators require only three inextensible limbs and, unlike most of the six-limbed parallel manipulators, their direct kinematics can be reduced to solving a polynomial in a single variable. In addition, by using three limbs instead of six other benefits such as lower possibility of mechanical interference between limbs can be realized. All of the minimanipulator actuators are base-mounted. As a result, higher payload capacity, smaller actuator sizes, and lower power dissipation can be obtained. In addition to the design discussion, kinematic analysis of the minimanipulators is also presented. © 1993 John Wiley & Sons, Inc.     

A GES/TS algorithm for the job shop scheduling

The job shop scheduling problem is a difficult combinatorial optimization problem. This paper presents a hybrid algorithm which combines global equilibrium search, path relinking and tabu search to solve the job shop scheduling problem. The proposed algorithm used biased random sampling to have a better covering of the solution space. In addition, a new version of N6 neighborhood is applied in a tabu search framework. In order to evaluate the algorithm, comprehensive tests are applied to it using various standard benchmark sets. Computational results confirm the effectiveness of the algorithm and its high speed. Besides, 19 new upper bounds among the unsolved problems are found.     

Application of response surface methodology for modelling of TiC coating on AISI D2 steel using a mechanical milling technique

The aim of this work is to identify relationships between the input variables and the process responses and to develop predictive models that could be used in the design of coating AISI D2 steel substrate with TiC powder by a ball milling process. A ‘one-factor design’ combining a response surface methodology with a modified cubic model was employed to modelling and optimisation of key operating factors involved in the ball milling procedure. The mentioned experiment was performed by changing these three variables, milling duration in the range of 10–50?h, fine and coarse powder particle size and as-received and hardened substrate. Coating thickness, microhardness and scratch hardness number were defined as process responses. Predicted values of responses obtained by using this model were in good agreement with experimental values. Optimum condition (24?h milling, hardened substrate and fine powder particle) supported the respective experimental test.     

The synthesize of CuWO<Subscript>4</Subscript> nano particles by a new morphological control method,characterization of its photocatalytic activity

In various branch of health sciences the nanoparticles are widely used for removing of bacteria, pollutes and etc. However, remove of chemical pollutes like azo dyes, pesticides, cyanide, colors, bacteria, parasites, antibiotics drugs and etc under photocatalytic conditions are still interest. In this work, we synthesized a nonparticle of copper tungstate (CuWO₄) via a co-precipitation method. We also investigated the effect of amino acids such as cysteine, glycine, and valine on morphology and particle size of nanoparticles. The structure and morphology of nano particles were characterized by XRD, SEM, VSM, EDS and DRS spectroscopy methods. The methyl orange (MO) degradation model was used for assessment of photocatalytic properties of as-prepared nanoparticles under UV irradiation. The results have been shown that the CuWO₄ nanoparticles can be decomposed about 81% of MO after 80 min UV irradiation.     

Solving the heterogeneous fixed fleet open vehicle routing problem by a combined metaheuristic algorithm

The vehicle routing problem (VRP) is a well-known combinatorial optimisation problem and holds a central place in logistics management. Many exact, heuristic and metaheuristic approaches have been proposed to solve VRP. An important variant of the VRP arises when a ?eet of vehicles is fixed and characterised by different capacities for distribution activities. The problem is known as the heterogeneous fixed fleet VRP (HFFVRP). The HFFVRP is a natural generalisation of the VRP with several vehicle types, each type being defined by a capacity, a fixed cost and a cost per distance unit, and can cover more practical situations in transportation. This problem consists of determining a set of vehicle trips of minimum total length in which a set of customers is to be satisfied in the demand constraints using identical vehicles with limited capacity. If open routes instead of closed ones are considered in the HFFVRP, the problem becomes a heterogeneous fixed fleet Open VRP (HFFOVRP) which has numerous applications in industrial and service problems. In this paper, a bone route algorithm which uses the tabu search as an improved procedure is utilised to solve the HFFOVRP. The proposed algorithm was tested empirically on a 24 of generated VRPs, and compared with elite ant system and ant colony system. In all cases, the proposed algorithm finds the best-known solutions within a reasonable time.     

Simultaneous spectrophotometric determination of caffeine and theobromine in Iranian tea by artificial neural networks and its comparison with PLS

In order to determine the amount of caffeine and theobromine, spectrophotometry was used as a simple, rapid and economical method. Because of severe overlapping between these components, artificial neural network was used. The 230–300 nm spectral window with 1 nm interval was used for data acquisition. An artificial neural network (5-5-3) with linear transfer function between input-hidden and hidden-output layers was trained and applied for prediction of concentration of these methylxanthines in four Iranian tea samples. The model was compared with PLS modeling method. HPLC technique was used as a standard method.     

Application of global optimization strategies to refinery hydrogen network

In this paper, a new method is presented in optimization of hydrogen network. The mixed integer non-linear programming (MINLP) and non-linear programming (NLP) problems have been solved with two methods, simultaneously. The linearization technique for non-linear programming models which proposed by McCormick (1976) and also a new method proposed by Faria and Bagajewicz (2011) have been used to solve these problems. Application of this new method is presented in global optimization of MINLP/NLP, and hydrogen network problem.