Wide tribology concept through the knowledge interaction from physics, chemistry and various engineering disciplines, has put tribology in a group with interdisciplinary sciences. This work gives information about the international standardization in the field of tribology, International Tribology Council, whose members consist of 36 national tribology society and associations from 34 countries worldwide and an overview of other international and regional organizations and institutions. Analysis of ISO, IEC and EN standards in various fields related to tribology and a view of the structure of most significant ISO Technical Committees related to standardization in tribology fields are presented.

The present study was aimed to removal of Cu(II) ions from aqueous solution by ultrasound-assisted adsorption onto the granular activated carbon obtained from hazelnut shells. The attention was focused on modeling the equilibrium and kinetics of Cu(II) adsorption onto the granular activated carbon. The granular activated carbon was prepared from ground dried hazelnut shells by simultaneous carbonization and activation by water steam at 950 degrees C for 2h. Adsorption isotherm data were better fitted by the Langmuir model than the Freundlich model in both the absence and the presence of ultrasound. The maximum adsorption capacity of the adsorbent for Cu(II), calculated from the Langmuir isotherms, in the presence of ultrasound (3.77 mmol/g) is greater than that in the absence of ultrasound (3.14 mmol/g). The adsorption process in the absence and the presence of ultrasound obeyed to the pseudo second-order kinetics. The removal of Cu(II) ions was higher in the presence of ultrasound than in its absence, but ultrasound reduced the rate constant. The intraparticular diffusion model indicated that adsorption of Cu(II) ions on the granular activated carbon was diffusion controlled as well as that ultrasound promoted intraparticular diffusion.

The PLM concept implies the use of heterogeneous information resources at different stages of the product life cycle, the joint work of which allows the user to effectively solve the problems of product quality and various costs. According to the principle of isomorphism of complex systems’ regularities, an effective PLM system must have these regularities. Unfortunately, this principle is not often fundamental when designing PLM systems. The purpose of this paper is to develop principles, based on the general theory of systems, for the design, operation and use of PLM systems and the implementation on their basis of the educational framework of a PLM system for threaded connections with the possibility of its effective development, research and study. The multi-agent approach to the development of a PLM system provides the necessary prerequisites for the emergence of system-wide regularities in it. The parallel work of agents is implemented using the actor model and the Ray Python-package. Agents for the logical inference of knowledge base facts, CAD/FEA/CAM/SCADA agents, agents for optimization by various methods, and other agents have been developed. Open-source software was used to develop the system. Each agent has relatively simple behavior, implemented by its rule function, and can interact with other agents. The system can work in interactive mode with the user or in automatic mode according to a simple algorithm: the rule functions of all agents are executed until at least one of them returns a value other than None. Examples of the system operation are given and system-wide regularities such as emergence, historicity and self-organization are demonstrated in it.

High-precision tapered threads are widely used in hard-loaded mechanical joints, especially in the aggressive environment of the drilling of oil and gas wells. Therefore, they must be made of workable materials often difficult to machine. This requires the use of high-performance cutting tools, which means the application of non-zero geometric parameters: rake and edge inclination angles. This study is based on analytical geometry methodology and describes the theoretical function of the thread profile as convoluted surfaces dependent on the tool’s geometric angles. The experiments were conducted using a visual algorithm grounded on the obtained function and prove the practical use of the scientific result. They predict the required accuracy of thread made using a lathe tool with a rake angle of up to 12°.