In this paper, dynamics of higher order multiple input multiple output (MIMO) cascade nonlinear systems, MIMOn, (⁠ $n>3$⁠), is analyzed using simulation of bifurcation and Lyapunov diagrams and spatial phase portraits. One of the characteristics of these systems is the possibility of spatial hyperchaos appearance. Control of spatial hyperchaos in MIMOn systems using modified Pyragas method is analyzed, also. The results are illustrated by example of MIMO6 system.

Petri nets are very appropriate for modelling and analysis of different systems. In this paper, examples of repairable and irreparable systems modelled using Petri nets have been given. Systems with cold and hot redundancy have been analyzed, also. The redundancy is illustrated using the example of the electric power system.

Indicators provide a foundational basis for offering essential data and describing changes in the environment at national, regional, or local levels. An indicator created to highlight the cause of change, the consequences of changes, the state of the environment, or the significance of implementing protective measures may be considered relevant for research. An adopted indicator, as part of the National List of Indicators, forms the basis for developing strategies, creating national policies, and establishing legal norms. Serbia’s National List of Environmental Indicators includes two noise indicators, which belong to the sixth thematic section and are classified as indicators of state. The overall noise indicator, designated as 6.40 and part of the sixth thematic section entitled “State”, describes noise disturbance over a 24-hour period, including the day-evening-night segments. According to the regulation, the day period lasts from 6 AM to 6 PM, the evening period from 6 PM to 10 PM, and the night period from 10 PM to 6 AM. The night noise indicator, also under the “State” category, with the designation 6.41, specifically describes noise disturbance during the night period (10 PM to 6 AM). This paper analyzes the use of indicators in noise control at both local and national levels. The use of indicators in noise control is a significant prerequisite for systematically and internationally accepted determination of the state of the environment, and for creating conditions to compare noise level values on an international level. Indicators are based on highly reliable data, which must be monitored in accordance with statistical correctness and internationally recognized methodology. The value of these indicators, published in the Report on the State of the Environment, becomes publicly available and is subject to comparative analysis.

Waste disposal sites significantly contribute to the degradation of primary environmental elements. In the Republic of Serbia, these waste disposal sites have been generated due to improper management of materials that are recyclable to varying degrees. Municipal waste disposal has led to issues such as contamination of surface and groundwater flows and a decline in the quality of agricultural crops. Current environmental management systems lack high levels of efficiency; preventive protection measures are not fully implemented, and corrective actions are frequently hindered by a lack of financial resources. Problem resolution is often limited to the application of “carpet-like” grass covers over degraded landscapes. The aim of this paper is to propose a model for overcoming these ecological issues. The proposal is based on a phased implementation, transitioning from simpler to more complex methods. Challenges associated with the direct application of modern reclamation methods include a shortage of professional personnel, financial constraints, and a lack of institutional readiness among the management of mining and energy complexes. The proposed environmental management system model for municipal solid waste landfills is based on Balanced Scorecard (BSC) and Critical Path Method (CPM) guidelines. By offering clear, efficient, innovative, and progressive strategic perspectives, this model establishes a robust foundation for multi-criteria decision-making and a multidisciplinary approach.