This paper deals with the computational aspect of the investigation of the relaxation properties of viscoelastic materials. The constitutive fractional Zener model is considered under continuous deformation with a jump at the origin. The analytical solution of this equation is obtained by the Laplace transform method. It is derived in a closed form in the terms of the Mittag-Leffler function. The method of numerical evaluation of the Mittag-Leffler function for arbitrary negative arguments which corresponds to physically meaningful interpretation is demonstrated. A numerical example is given to illustrate the effectiveness of this result.

Undoubtedly, Low-Altitude Unmanned Aerial Vehicles (UAVs) are becoming more common in marine applications. Equipped with a Global Navigation Satellite System (GNSS) Real-Time Kinematic (RTK) receiver for highly accurate positioning, they perform camera and Light Detection and Ranging (LiDAR) measurements. Unfortunately, these measurements may still be subject to large errors-mainly due to the inaccuracy of measurement of the optical axis of the camera or LiDAR sensor. Usually, UAVs use a small and light Inertial Navigation System (INS) with an angle measurement error of up to ${0.5}^{\circ }$ (RMSE). The methodology for spatial orientation angle correction presented in the article allows the reduction of this error even to the level of ${0.01}^{\circ }$ (RMSE). It can be successfully used in coastal and port waters. To determine the corrections, only the Electronic Navigational Chart (ENC) and an image of the coastline are needed.

This paper presents a new approach for searching the most favourable mechanical assembly sequence. The proposed method is described and its basic modules are presented. The concept is based on the assumption that the method should help the engineer in specifying the best assembly sequence with...

This paper presents the results of experimental tests on the static tensile strength and relative elongation of three-layer films containing varying proportions of recycled polyethylene and subjected to an embossing process. Films containing varying proportions of recycled low-density and high-density polyethylene were produced by blown film extrusion. The embossing process was carried out under varying processing conditions, and embossing patterns with different geometrical characteristics were produced on the three-layer films under investigation. The films were manufactured and the experimental tests were conducted under industrial conditions. Based on the results obtained, the effects of three different embossing pattern geometries and the embossing process parameters on the tensile strength of three-layer films made from recycled polyethylene were evaluated in the machine and transverse directions. The experimental results enabled the identification of embossing pattern geometries and recycled polyethylene contents that increased static tensile strength in selected material–process combinations. No statistically significant improvement in elongation at break was confirmed compared with the non-embossed reference films. The findings are limited to static tensile strength and elongation at break in the machine direction (MD) and cross direction (CD), which contribute to improving certain functional properties of refuse bags, specifically ensuring adequate load-bearing capacity for the waste they contain.