Efficient interaction between PHP (Hypertext Preprocessor) applications and MySQL databases is essential for the performance of modern web systems. This study systematically compares the two most widely used PHP APIs for working with MySQL databases—MySQLi (MySQL Improved extension) and PDO (PHP Data Objects)—under identical experimental conditions. The analysis covers execution time, memory consumption, and the stability and variability of results across different types of SQL (Structured Query Language) queries (simple queries, complex JOIN, GROUP BY/HAVING). A specialized benchmarking tool was developed to collect detailed metrics over several hundred repetitions and to enable graphical and statistical evaluation. Across the full benchmark suite, MySQLi exhibits the lowest mean wall-clock execution time on average (≈15% overall). However, under higher query complexity and in certain connection-handling regimes, PDO prepared statement modes provide competitive latency with improved predictability. These results should be interpreted as context-aware rankings for the tested single-host environment and workload design, and as a reusable benchmarking framework intended for replication under alternative deployment models. Statistical analysis (Kruskal–Wallis and Mann–Whitney tests) confirms significant differences between the methods, while Box-plots and histograms visualize deviations and the presence of outliers. Unlike earlier studies, this work provides a controlled and replicable benchmarking environment that tests both MySQLi and PDO across multiple API modes and isolates the impact of native versus emulated prepared statements. It also evaluates performance under complex-query workloads that reflect typical reporting and analytics patterns on the ClassicModels schema. To our knowledge, no previous study has analyzed these factors jointly or provided a reusable tool enabling transparent comparison across PHP–MySQL access layers. The findings provide empirical evidence and practical guidelines for choosing the optimal API depending on the application scenario, as well as a tool that can be applied for further testing in various web environments.

In this paper, the aim of the research refers to the analysis of the views of the citizens of seven cities in Republic of Serbia on the concept of smart cities. The concept of smart cities is being adopted worldwide, with the exponential growth of smart technologies. In the empirical part of the paper, research was conducted by the author of the paper in connection with the subject of the research. The research instrument used in this paper is a survey that was created online and then distributed to survey students. The sample of respondents consisted of 294 respondents, from whom it was planned to get opinions on the concept of smart cities, to what extent it positively or negatively affects everyday life. The research results indicate the level of respondents’ ignorance of the concept of smart cities. Also, there is the uneven implementation of smart solutions in rural and urban areas in Republic of Serbia. The recommendation is to enable the even development of all cities and educate the population about the concept of smart cities, in the sense that there are no significant threats to security and privacy, and that resources such as time and costs are highly, their savings, closely connected with the concept of smart cities.

This paper presents an analysis of image transmission quality with embedded digital watermarking over an atmospheric turbulence channel. The channel is modeled using the Zero Boresight Chi-square–Inverse Gamma statistical model. Particular attention is devoted to the influence of two key parameters: the intensity of atmospheric turbulence and the Rician K-factor. Objective metrics, namely the Mean Square Error (MSE) and the Peak Signal-to-Noise Ratio (PSNR), are employed for quality evaluation. The results demonstrate that atmospheric turbulence considerably degrades transmission quality, whereas the Rician K-factor plays a crucial role in its enhancement. Furthermore, the effect of digital watermarking on preserving information integrity is verified. The findings provide valuable insights into the reliability of Free-Space Optical (FSO) communication systems and support the optimization of future system designs.

This paper introduces a novel statistical model for the performance analysis of hybrid RF/FSO (radio frequency/free-space optics) communication systems. The RF channel is modeled using the Nakagami-m fading distribution, while the FSO channel is characterized by a Chi-square–inverse Gamma distribution to account for atmospheric turbulence and pointing errors. A closed-form expression for the cumulative distribution function (CDF) of a one-hop hybrid RF/FSO system is derived under a selective combining scheme, formulated as a function of the average signal-to-noise ratio (SNR). The resulting CDF is expressed in terms of the extended generalized bivariate Meijer-G function (EGBMGF). Furthermore, new analytical expressions for the average bit error rate (ABER) are obtained for both the hybrid RF/FSO system and its FSO-only counterpart under coherent binary phase-shift keying (CBPSK) modulation. A detailed comparative analysis is performed across varying channel parameters and turbulence conditions. Numerical results, presented graphically, demonstrate the superior robustness of the proposed hybrid scheme under severe turbulence and misalignment effects.