Scientific Journal of Gdynia Maritime University

A Stochastic Petri Net-Based Model of Non-Enzymatic RNA Degradation

Agnieszka Rybarczyk — 2024-09-30

In recent years, RNA research has grown due to the discovery of its important role in biological systems. RNA molecules are involved in protein synthesis and play a critical role in gene expression. Many of these molecules are produced through the enzymatic digestion or spontaneous degradation of larger molecules, and are consequently essential for cellular processes. The mechanisms of RNA degradation appear to be one of the most important factors influencing RNA activity.

In this study, a stochastic Petri net-based model of spontaneous (non-enzymatic) RNA degradation was built and analysed. The model was analysed using t-invariants, MCT sets, and simulation-based analyses. The systems approach enabled a thorough analysis of the phenomenon, resulting in significant biological insights.

Speed Variation of a Cage Induction Motor under Square Voltage Modulation

Piotr Gnaciński — 2024-09-30

Cyclic voltage fluctuations can be considered as a superposition of the fundamental voltage component, subharmonic and interharmonic components – that is the components of frequency less than the fundamental one or not being its integer multiple. A commonly occurring case of voltage fluctuations is square voltage modulation. This paper deals with the effect of square voltage modulation on the rotational speed of an induction motor. The results of the FEM computations are presented for a cage induction motor with a rated power 3 kW and various parameters describing the voltage modulation.

Effect of Rectangular Voltage Fluctuations on Currents of Single-Phase Induction Motors

Marcin Pepliński — 2024-09-30

Various power quality disturbances commonly occur in a power system, including voltage fluctuations. These can be analysed as simultaneous occurrences of voltage subharmonics and interharmonics of various frequencies – components of frequency less than the fundamental one or not being its integer multiple. This work deals with the impact of voltage fluctuations on currents of a single-phase induction motor. The results of the research on currents are presented for rectangular amplitude modulation and are compared with the investigation results under sinusoidal modulation and the appearance of a single voltage subharmonic.

Characteristics of the Sorption Properties of Dried Hemp

Julia Ziajka — 2024-09-30

The study is aimed at assessing the sorption properties of dried hemp (Cannabis sativa L.), which determines the storage stability of the raw material. The statistical and desiccator method was used, with the BET equation used to mathematically interpret the course of the water vapor sorption isotherms. Based on the study, it was found that product IV had the best sorption properties - dried hemp with the lowest degree of fragmentation and non-decarboxylated. Product IV was characterized by the highest water absorption capacity and the highest values of the BET equation parameters (6.13 g/100 g d. m. for the capacity of the monomolecular layer and 215.3 m²/g for the specific sorption surface).

Colossus from Algebron – Gamification as a Tool to Engage Students in Learning Mathematics

Barbara Wikieł — 2024-09-30

Gamification is a tool that allows for high engagement in performing tasks that have been previously considered difficult or uninteresting. It works exceptionally well in education as it supports students in developing habits of learning and provides them with a visual representation of their progress in acquiring knowledge and skills. Skillful design of gamified academic courses enables the achievement of the educational goals set by both the students and the academic teachers. Gamification is helpful for subjects that seem challenging, require a significant amount of effort, or are simply perceived by students as uninteresting or useless. The purpose of this paper is to discuss various aspects of engaging students in the process of learning mathematics by the gamification of linear algebra.