International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Shielded metal arc welding is widely used in heavy industries in partly shipbuilding and ship repair. This method didn’t required special personal skills and equipment. Different scientists are analyzed welding parameters, mechanical characteristics and chemical composition in welding seam but interesting is to be investigated welding arc characteristics in different electrodes. The paper deal with analyze of welding arc parameters in shielded metal arc welding. For this purpose on mild steel plates are welded seams with different diameters of electrodes and different welding current. In welding process are measured welding arc burning time, length of electrodes melted part, welding machine voltage and weight of melted electrodes part. For analyze welding arc parameters are used response surface methodology method (RSM). Used RSM in the paper is 2k factorial design where k=2 factors. The influence of each to other factors of welding arc is presented by meta models.

The report examines different models and approaches for motivating and attracting personnel to the British Armed Forces. Positive and negative approaches for motivating service members are theoretically analysed and the most attractive among them are specified. The results obtained could be used in the development of an integrated strategy to motivate service members in the Bulgarian Armed Forces.

Тhe article deals with probabilistic and statistical models of vibration processes. The covariance moment is considered. A dimensionless normalized covariance is introduced. To evaluate these theoretical characteristics, we used a statistical set of observational data. Observations that are cleared of measurement errors are combined into a sample of a specific volume. Random processes in vibration analysis are considered in detail. The characteristics of random processes are given: attenuation with a random beginning, a linear process with a random slope, and a harmonic process with a random amplitude. A statistical model of a linear system based on observations of input and output vibration processes is considered in detail.

In the recent years both academics and practitioners have paid attention to environmental issues. With increasing complexity and diversity of implemented environmental practices they try to find the successful model of environmental management and sustainable development. Although a large number of environmental management models have been developed, there is no good solution because the models are different in their „nature”. Many of them are evolutionary (stage, phase models) models that described a development in time consisting of an increasing integration of environmental concern into business policy and strategy. Others are typology models that characterizes companies’ positions, without assuming such a growing responsiveness. The aim of the article is to present the characteristics of sustainable and the corporate environmental management models.

The report analyzes the place and role of the problem of quality and reliability of production /agricultural machinery/ under the conditions of the market economy is the basis of marketing and business. In a market economy the main driving forces of the business are: marketing, quality and reliability of production and services.

It turns out that we need to change our way of thinking and action. We must get used to the idea that the marketing approach and innovative solutions challenge the consumer to produce and service high quality and reliability.