This study aims to identify the most suitable IoT communication protocol for a digital twin architecture, focusing on meeting the demands of real-time data transmission with stability and security. The research methodology involves a comparative performance analysis of MQTT over TCP, MQTT over WebSocket, and HTTP protocols, evaluating their latency, connectivity stability, and IoT application feasibility using an ESP32 microcontroller and DHT22 sensor setup. The experimental results demonstrate that MQTT over TCP achieves the lowest average latency at 290.5 ms, while MQTT over WebSocket exhibits more stable latency profiles with a 193.2 ms standard deviation; HTTP, despite its broader compatibility, showed higher average latency of 342.6 ms with a 307.9 ms standard deviation. These findings provide valuable insights for digital twin implementations, enabling developers to make informed protocol selections based on specific requirements, whether prioritizing real-time performance through MQTT protocols or emphasizing system compatibility and simplicity through HTTP.

This study examines the application and implementation of energy-efficient measures and strategies for use in buildings aimed at achieving the goal of virtually zero energy consumption by buildings. In particular, the aim of the study is to introduce integrated solar devices into the building, functioning as a functional component of the structure for heat storage, in order to increase the flexibility of the structure while maintaining comfortable conditions inside. This article discusses an experimental comparison of flat and tubular solar collectors in the southern and northern regions of Kazakhstan. Compared to glass (S = 3), a tubular solar collector has a coefficient of thermal conductivity that is two times lower for single-layer elements and 2.5 times lower for double-layer elements. This means that less heat is lost. A flat solar collector was also developed, a heat-insulating translucent double-glazed window with reduced pressure, and the coolant is made of thin-walled corrugated stainless-steel pipe. In this collector, there is a constant circulation of heat, which increases the efficiency of heat transfer by eliminating additional partitions between the panel and thermal insulation. A calculation was carried out that allowed us to determine the productivity and useful gain for two collectors. The annual increase in the useful energy of flat solar collectors is about 12780000 kJ/hour and 20100000 kJ/hour for tubular solar collectors; therefore, the annual increase in the useful energy of evacuated tubular collectors is 20% more than that of flat plate collectors in the northern region.

Enhancing Sustainable Biogas Generation Through a Real-Time Digital Twin of a Modular Bioreactor

As the Industrial Internet of Things (IIoT) expands, maintaining a high level of security and reliability is becoming increasingly important for uninterrupted operations. Encryption (TLS/SSL and AES-256) and intrusion detection and prevention systems (IDPS) are essential. In addition, the platform uses neural network algorithms, namely long short-term memory (LSTM) and hybrid CNN-LSTM models, to identify anomalies in real time, which contributes to a rapid response to potential failures or cyber threats. Through the use of model compression and explainable AI (XAI) techniques, the architecture adapts to a variety of industrial scenarios without compromising performance or transparency, helping industry professionals strengthen security measures and improve real-time anomaly detection in the ever-evolving IIoT landscape.

This article discusses the mathematical models of the individual structures and modes of operation of a double-circuit solar collector with thermo siphon circulation. To perform this task, we considered a new design of a flat solar collector with thermo siphon circulation, in which the heat transfer coefficient was increased by eliminating additional partitions between the panel and thermal insulation. The efficiency of the solar collector is achieved due to the presence of the metering tank and the heat pump in the tank, where the condenser and evaporator are made in the form of a “spiral in a spiral” type heat exchanger, and the heat exchanger pipelines are placed one above the other, which allows increasing the area and intensity of heat exchange. The result of this work is a theoretical and mathematical analysis of the unsteady thermal regime of flat solar collectors on the modes of operation under consideration. Based on the results of the analysis, it is possible to optimize individual structural elements, as well as to predict the thermal regime and select alternative solutions for the design of flat solar collectors and the choice of operating modes.

This article presents a comparative analysis of data monitoring and visualization tools—Prometheus and InfluxDB—in the context of digital twins (DTs) applied to industrial settings. DTs optimize production processes using industrial internet of things (IIoT) technologies. Mathematical models assessed the tools based on response time, resource consumption, throughput, and reliability. Prometheus is better suited for high-frequency monitoring, achieving a response time of 0.01 seconds and processing up to 10,000 metrics per second—10–15% better than InfluxDB. It consumes 1.5 times less memory (100 MB versus 150 MB), making it faster and more resource-efficient. Conversely, InfluxDB excels in long-term storage and analytics, handling up to 8,000 metrics per second with a response time of 0.09 seconds. However, it requires more resources, including higher CPU usage (20% versus 15%). Both tools integrate seamlessly with Grafana for visualization, offering flexibility for real-time monitoring and decision-making. The study provides actionable insights for selecting monitoring systems based on project-specific requirements, highlighting Prometheus’s efficiency in dynamic scenarios and InfluxDB’s strength in analytics-focused tasks.