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In this work the method for the treatment of industrial waste waters effluents containing hexavalent chromium in three companies during process of treating metal surface with chromic acid is described. Industrial water polluted with hexavalent chromium is collected in separate sewage system. Polluted water is collected in precipitation tanks which are directly connected with neutralization reservoirs. The treatment process includes pre-neutralization by lime-milk, sedimentation, flocculation, ion exchange and final neutralization of purified water before its final delivery to river flow. The samples from two river recipient of industrial water have been collected and analyzed. The impact on pollution of these eco systems was evaluated. The toxicity effect of hexavalent chromium on people health was discussed.

This paper establishes the system for termining the production of wooden chairs which is the consisting part of the system for production planning. It particularly discusses the termination of the production according to the structural components of the product in thermic units. It defines the simulation programme for the solution of the problem, which is projected in the way that it provides a continuous realization of the logistic chain from the moment of the purchase of repromaterial, through the realization of the working errand in the workshop, to the delivery of the product to the buyer. The simulation experiment starts with the assumption that the necessary repromaterial is opportunely accessible in the entrance storehouse. The programme, which is managed by the automatically calculated priorities of the working errands, completely describes what happens in the workshop.

They give the soles of technological design process using fuzzy logic for metal cutting, referring to the determination of all the elements of production process: the dimensions and quality of the workpiece material, the sequence and scope of operations, the order and content of the procedures, the size of the type of machine types and tool types and gauges, regime and time of processing. It further explains manufacturability machine parts for robust design of a new product. He also offers manufacturability for cylindrical, prismatic workpieces and boxes. It explains the mathematical expressions of fuzzy logic which described above manufacturability. In fuzzy logic are used mathematical operations minimization and maximization. They are used to determine the critical solutions and choice of cost effective solutions. Provides an example of using the model to determine of the manufacturability.

completely defined, i.e., described. In the same way, it was proven that their character depended on the character of the frictional force. At the end of the paper, the derived relations were used to determine the condition of the stability of the self-exciting oscillations and qualitatively analyze the acquired results with a special focus on the effects of specific factors on the observed oscillatory process.