Journal of natural and applied sciences

Constract A New Ballistic Missile model by Line Graph and Measuring its Reliability

2026-07-15T07:52:43+00:00

This study presented a mathematical approach for analysing the reliability of a ballistic missile system using the Line Graph technique from graph theory. The missile structure was modelled by representing the relationships between its main components such as the missile body, propulsion system, fuel system, payload, control unit, guidance system, and fins. The reduction method was applied to simplify the complex network of components and identify the critical paths within the system.

Several reliability measures were employed to evaluate the system performance, including system reliability, Mean Time to Failure (MTTF), hazard rate, Shannon entropy, and extropy. These measures provide a theoretical framework for understanding system behaviour and uncertainty in failure processes. The use of line graphs also helped visualize the structural relationships between components and analyze reliability behavior over time. Overall, the proposed model demonstrates how graph theory and reliability techniques can be combined to study complex engineering systems and support the improvement of system design and performance under operational condition

Complementary Topological Graphs: Structural Properties and Domination Parameters

2026-07-15T07:57:08+00:00

In this thesis, a new type of graph called the complementary topological graph, denoted by , is introduced and studied. This graph is constructed from a finite set equipped with the discrete topology, where the vertices represent all non-empty proper subsets of , and two vertices are adjacent whenever their union equals the whole set . The work focuses on studying several structural properties of , including the order, size, degree of vertices, Eulerian properties, and chromatic number. It is shown that the graph contains vertices and edges, where . In addition, the graph is proved to be regular with degree . Based on these properties, it is concluded that is neither Eulerian nor semi-Eulerian for all . The chromatic number of the graph is also determined and shown to be equal to .

Furthermore, this thesis investigates domination in complementary topological graphs under some graph operations, particularly the corona and join operations. The domination number for these operations is obtained and characterized through several results and examples. The results presented in this thesis provide a deeper understanding of the relationship between graph theory and topology, and they may serve as a basis for future studies on complementary topological graphs and their applications in different areas of graph theory.

Lightweight Machine Learning For Real-Time Intrusion Detection On Resource-Constrained Iot Gateways: A Comparative Study

2026-07-15T08:02:23+00:00

We propose an energy-aware framework that uses a light-weight reinforcement learning (RL) controller to adaptively select model variants and runtime knobs (sampling rate, quantization, early-exit thresholds) for intrusion-detection tasks on resource-constrained IoT gateways. The controller balances detection utility against latency and energy cost and operates with a small profiling footprint. We evaluate the approach on standard IoT flow datasets and commodity SBCs; metrics include accuracy, F1, p50/p95 latency, model size, memory footprint and Joules per inference. The framework yields substantial energy reductions under realistic workloads while maintaining comparable detection performance to static high-accuracy models. Reproducible measurement scripts and artifacts are provided..

The Impact of Crystal Defects on the Electronic Properties of Solid Materials

2026-07-15T08:04:44+00:00

Crystal defects play a crucial role in determining the electronic properties of solid materials. Real crystals always contain imperfections that significantly influence electrical conductivity, carrier mobility, band structure, and recombination processes. This research reviews the different types of crystal defects and discusses their effects on the electronic properties of solids, particularly semiconductors used in modern electronic and optoelectronic devices. Furthermore, the study highlights recent applications where defect engineering is employed to optimize material performance.