JOURNAL OF ENGINEERING SCIENCE <p><strong>ISSN 2587-3474 / E-ISSN 2587-3482</strong></p> <p>JES is an international journal that aims to publish original papers focused on the most modern theories and their applications.</p> Technical University of Moldova en-US JOURNAL OF ENGINEERING SCIENCE 2587-3474 OVERSIZED ROAD TRANSPORT - PARTICULARITIES, REALIZATION CONDITIONS, PROBLEMS AND DEVELOPMENT PERSPECTIVES <p>Transport is in continuous evolution, regardless of the activity sector. Road transport faces various obstacles, and their management is a crucial part of planning and executing bulk transport operations. One of the main obstacles is the low height of bridges or power lines along the planned route. To avoid collisions with these obstacles, detailed studies of the route are carried out, identifying potential conflict points in advance. Preventive measures such as temporarily raising power lines or temporarily changing the height of bridges can be implemented to ensure the smooth passage of oversized cargo. Ground communication routes with a curved axis represent another limiting factor in oversized transport. Solutions include planning routes to minimize the number of bends or using special trailers with directional axles. These trailers allow for easier cornering and ensure that the transport can cross terrain with difficult geographical features. The necessary authorizations also represent a major obstacle. Oversized transport often involves dimensions and weights that exceed the usual limits, which is why it is mandatory to obtain authorizations issued by competent public authorities. But this stage, by way of consequence, determines the legality and admissibility of carrying out transport operations. To manage obstacles in oversized transport, a proactive approach is essential, with detailed route analyses, the implementation of appropriate preventive measures, and compliance with applicable regulations. These solutions contribute to the efficiency and safety of oversized road transport, ensuring harmonious integration in the context of the existing infrastructure.</p> Nina Garstea Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 7 17 10.52326/jes.utm.2024.31(1).01 MEAN-OF-2-4 QUICKSORT <p>By combining the Median-of-three and Regrouping-3 quicksort methods, the Joint quicksort is proposed, largely free from the shortcomings of the first two. For example, the time complexity of Joint quicksort, in case of lists of n equal elements, is O(n). Analysis of the dependence of Quicksort time complexity on the ratio of the derived sublist sizes shows a relatively slow increase in sorting time as the ratio in question decreases from 0.5 to 0.1. The proposed category of Mean-of-K (MeK) sorting algorithms provides for the determination of pivot elements as the mean of K elements. It is shown that, in terms of sorting time, at K ∈ [1, 4] and size r of the list/sublist of elements to be sorted, it is convenient to use (roughly): Insertion sort at r ≤ 9, Me2 quicksort at 10 ≤ r ≤ 21, Me3 quicksort at 22 ≤ r ≤ 46, and Me4 quicksort at r &gt; 46, yielding the Mean-of-2-4 quicksort method. It was found that the determination of pivot elements in the Median-of-three method requires more calculations than in the Mean-of-3 method; respectively, using Mean-of-3 method could also reduce sorting time. Of course, Mean-of-2-4 method could reduce this duration even further.</p> Ion Bolun Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 18 33 10.52326/jes.utm.2024.31(1).02 DEVELOPMENT OF FUNCTIONAL PROTOTYPE OF ELECTRICAL LOWER ESOPHAGEAL SPHINCTOR STIMULATOR <p>Scientific and technical innovations done since 1960s resulted in successful development and implementation in medical practice active implantable devices. Most of them are using traditional chemical batteries with limited longevity. Further research progress and development of semiconductors and passive elements base are allowing now to develop fully battery-free implants that could do same tasks, but with much lower sizes, less complication and more ease of use. In this article will be shared results of own development of an wireless-powered, remote controlled, fully implantable electrostimulator of lower esophageal sphincter (WIPLES) aimed to treat gastroesophageal reflux disease, that is very common in current days.</p> Vladimir Vidiborschii Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 34 44 10.52326/jes.utm.2024.31(1).03 METHODOLOGY APPLIED IN THE CONSTRUCTION OF STRUCTURES USING NATURAL AND ALTERNATIVE MATERIALS FOR STABILIZATION WORKS IN ROAD CONSTRUCTION <p>The analysis of the current state of applications and the results of studies carried out at international level have led to the approach of an eco-efficient methodology for the recovery of waste generated from construction activities, demolition, and the addition of alternative stabilising materials to obtain optimized structures capable of providing a higher quality of the works carried out. Three types of stabilising slurry agents were selected for the experimental programme: the water-based polymer product AggreBind (AGB-BT), the Terra 3000 solution based on the Power binder, and the Earthzyme polysemantic product. Experimental studies on the use of these types of products in earthworks for stabilizing embankments, building and repairing road systems and industrial platforms have shown significant increases in strength and bearing capacity. The use of these environmentally beneficial alternative materials has led to significant reductions in construction time, decreasing total construction and maintenance costs in the short and long term.</p> Cornelia - Florentina Dobrescu Eugeniu Braguța Olga Harea Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 45 54 10.52326/jes.utm.2024.31(1).04 EVALUATION OF SEISMIC FORCES ACCORDING TO EUROCODE 8 AND SNiP II-7-81. COMPARATIVE ANALYSIS <p>The evaluation of seismic forces is very important for the design of all types of structures. In the present, Republic of Moldova is in a period of transition in the construction industry from the national design norms to the European design norms. The comparison provides an interesting and imperative approach in design of structures. During the design process it is very important to be aware of all the forces acting on a structure, especially the accidental forces. This paper presents a comprehensive analysis of a concrete frame structure, subjected to seismic action. A calculation is performed according to the current national design code SNiP II-7-81 and according to Eurocode 8. The purpose of the paper is the quantitative comparison of the values of the seismic forces and the qualitative evaluation of the factors that influence these forces.</p> Vadim Țurcan Mihail Ștascov Evgheni Cutia Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 55 65 10.52326/jes.utm.2024.31(1).05 PROPANOL DETECTION DEVICE FOR THE PURPOSE OF MONITORING THE QUALITY OF THE ENVIRONMENT <p>The aim of this study was to develop and characterize CuO/Cu2O functionalized with AgPt nanostructures for gas sensing applications. Environmental pollution remains a pressing global concern, requiring effective detection methods. Metal oxide nanostructures, such as those based on copper oxides, offer promising solutions due to their sensitivity and selectivity for various gases. The research investigated the morphology and structure of the nanostructures using techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy. In addition, the nanostructures were functionalized with noble metals such as silver and platinum to enhance their sensory properties. The deposition of polymer layers has been investigated as a method to improve sensor selectivity. The gas sensing properties of the CuO/Cu2O/AgPt nanostructures were evaluated using the Keithley 2400 source meter and showed high sensitivity to gases such as propanol, acetone, hydrogen, and ammonia at elevated temperatures. The results showed that higher operating temperatures result in faster response and recovery times. In addition, the nanostructures exhibited saturation in response at higher concentrations of certain gases. These results highlighted the potential of CuO/Cu2O/AgPt nanostructures in environmental monitoring applications, particularly in industries prone to gas emissions. Overall, this research contributes to the advancement of gas sensing technology for pollution prevention and control efforts.</p> Maxim Chiriac Dinu Litra Cristian Lupan Oleg Lupan Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 66 74 10.52326/jes.utm.2024.31(1).06 POSSIBILITIES OF OBTAINING AND VALORIZING DIETARY FIBERS IN THE CONTEXT OF THE CIRCULAR BIOECONOMY <p>This article aimed to review the recent literature on the characterization of dietary fibers and their role in the human body, focusing on the methods of extraction of dietary fibers from agro-food waste as well as their use in various areas of the food industry. Dietary fibers are biologically active substances with beneficial effects on human health. Soluble dietary fiber is involved in reducing cholesterol levels and blood sugar levels, while insoluble dietary fiber helps regulate intestinal transit and maintain colon health. It would be useful to identify the extraction procedures and characterization of dietary fibers from agro-food waste. Fruit waste contains relevant amounts of bioactive compounds, such as: phenolic acids, flavonoids, lignins, carotenoids, etc. In addition, fruit waste contains significant amounts of dietary fiber with nutraceutical important activities, such as modulating the intestinal microbiota, lowering cholesterol, triglycerides and glycemic load in the blood. Hence, obtaining dietary fiber from agro-industrial waste can solve a number of economic and environmental problems that aim reducing waste, increasing the sustainability and profitability of companies in the Republic of Moldova. Dietary fiber can be used in various types of food, such as products of bakery and confectionery, meat, dairy products, and pasta. They can be used as stabilizers with an impact on food texture or ingredients with low caloric value, partially replacing caloric constituents such as fats, starch or sugars. Another important property is the prebiotic effect of dietary fibers. This property is determined by the fact that dietary fibers are indigestible or poorly digestible and are fermented selectively by intestinal microbiota, conferring health benefits to the host.</p> Svetlana Erşova Daria Suhovici Tatiana Cesko Maria-Marcela Barbaroș Liliana Popescu Aliona Ghendov-Mosanu Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-05-19 2024-05-19 31 1 75 96 10.52326/jes.utm.2024.31(1).07 EXPLORING THE MICRO AND MACRO TERROIR OF FETEASCĂ NEAGRĂ WINE FROM MOLDOVA <p>This study delves into the intricate realm of Moldovan winemaking, focusing on the iconic Fetească Neagră grape variety. The research highlights the importance of indigenous grape varieties in shaping a unique wine identity for the region. Drawing on the concept of terroir, the study investigates the microbial terroir specific to three designated geographical regions in Moldova during the 2022 vintage. The research employs a multifaceted approach, combining climate data analysis, mini vinification experiments, microbial DNA extraction, and sensory evaluation techniques. Results reveal significant variations in climatic conditions and microbial diversity across the three regions, influencing the sensory characteristics of the resulting wines. On vintage 2022 the Codru is temperature, and the Stefan-Voda and Vadul lui Traian are warm climates. All the 3 regions are moderately dry. The Stefan Voda is 14.0%, and manifests the highest ethanol content among the regions, alongside the lowest pH level. The sensory evaluations show Stefan Voda evincing heightened creaminess, Codru showcasing prominent herbal nuances, and Vadul lui Traian displaying elevated scores in berry, cherry, violet, and black pepper descriptors. Through meticulous analysis, the study underscores the dynamic interplay between environmental factors, microbial communities, and wine attributes, shedding light on the complex tapestry of Moldovan winemaking. Ultimately, this research contributes to a deeper understanding of terroir-driven wine production and emphasizes the importance of preserving indigenous grape varieties to uphold the distinctiveness of Moldovan wines on the global stage.</p> Fei Wang Meiling Yao Gheorghe Arpentin Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 97 111 10.52326/jes.utm.2024.31(1).08 HARNESSING GRAPE POMACE: NUTRITIONAL ASPECTS, RECOVERY AND EXTRACTION TECHNIQUES FOR HEALTH BENEFITS <p>Nowadays, grapes represent the third most widely cultivated horticulture crop in the world. For the Republic of Moldova, grapes have been recognized as the most culturally important crop. About 70% of the total production of Moldovan grapes is processed in the wine industry, 30 % of which are by-products that tend to be not fully exploited, being frequently burned or landfilled. Due to its chemical composition, grape pomace is one type of agricultural waste that can be used to achieve sustainability in the food business by converting waste into useful resources. In this sense, the pomace chemical composition, with demonstrated antioxidant potential, is a viable source of biologically active compounds, as a cheap agricultural waste product, for the development of functional products. This paper is an overview of the characteristics and potential uses of wine industry waste, namely grape pomace and explores the implementation of eco-friendly technologies that have the potential to convert this perishable material into a unique ingredient, unveiling fresh opportunities for the grape pomace's utilization and consumption.</p> Eugenia Covaliov Olga Ruseva Vladislav Resitca Olga Deseatnicova Tatiana Capcanari Natalia Suhodol Copyright (c) 2024 JOURNAL OF ENGINEERING SCIENCE 2024-03-31 2024-03-31 31 1 112 125 10.52326/jes.utm.2024.31(1).09