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The old bridge structure, are subjects that must be monitored in bridge maintenance. Bridge detection supervision is very necessary to determine structural deformation caused by normal operations or environmental impacts such as temperature, humidity and heavy vehicle loads. Monitoring the structure as a whole also needs to be carried out after extreme conditions occur, such as an earthquake. Research on structural dynamics analysis of steel frame bridge conditions to determine the behavior of the structure. Vibration data is read using a wireless sensor network or accelerometer. The vibration mode signal obtained is processed using Fast Fourier Transform (FFT) analysis via MATLAB software, which will produce a graph of the relationship between the frequency domain and the time domain. Through this graph, the dynamic characteristics of the bridge structure can be analyzed, with several variations in the condition of the bridge structure.

The processing of natural fibers as raw materials for paper has grown over the past few years. However, the use of composite paper as a printing substrate has several drawbacks. One of them is the low color reproduction quality of printed images on paper made from natural fibers, caused by the insufficient whiteness of the paper. This study aims to investigate the effect of titanium dioxide (TiO₂) addition on the color reproduction quality of composite paper based on sugarcane bagasse fiber. TiO₂ was varied at concentrations of 0%, 10%, and 20%. Printing process was carried out using an inkjet printer with standard CMYK and RGB color patches. After that, the printed results were measured using colorimeter with D65 illuminant. Color distribution analysis was processed using MATLAB software. The results showed that the addition of TiO₂ increased the whiteness of the paper, as indicated by the higher L* values. The color gamut visualization demonstrated that the gamut area expanded as the TiO₂ content increased. This result shows that the addition of TiO₂ affects the color reproduction quality of composite paper.

Control systems with time delays introduce system stability problems because time delays cause exponential effects to the system response. Conventional root-locus methods cannot be used directly on systems with delays due to irrational mathematical forms. This study analyzes the shifting effect of time delay on the stability of linear control systems by using the first-order Padé approach to enable the application of the root-locus method. The system model used is a second-order linear system with a transfer function of , and is analyzed under conditions without delay and with delays of 0.5, 1, and 1.5 seconds. Simulations were performed using MATLAB software. The results show that the addition of delay causes a right pole shift of the imaginary axis, reduces the stability margin of the system, and results in a more oscillative response as well as a longer time for the system to stabilize. The first-order Padé approach is shown to be effective in facilitating the visual analysis of stability in time-delayed systems. The findings make a practical contribution in adapting classical analysis techniques to the needs of modern control systems and can be widely applied in the development of network-based control systems, industrial automation, and real-time control.