JOURNAL OF ENGINEERING SCIENCE

QUALITY OF PUBLIC TRANSPORT SERVICES IN CHISINAU

Igor Rotaru, Victor Ceban — Mon, 15 Jul 2024 00:00:00 +0000

The quality of transport services represents the most comprehensive and synthetic attribute that reflects the performance of a transport system. In the public transport system, the quality of service is largely influenced by the way passengers perceive its performance. The quality of transport services is assessed according to a number of technical and economic indicators that characterize the performance of transport operators within the framework of the urban public transport system. The article aims to identify the criteria for evaluating the quality of urban public transport services based on the study carried out for the public transport system of the municipality of Chisinau and to describe the indicators that reflect the performance offered by the public transport system, as perceived by passengers. It should be noted that the quality of the urban public transport service has a direct impact on the quality of life of all city residents. The study includes a concrete survey of the beneficiaries of public transport in the municipality of Chisinau, which analyzes the quality criteria and their rate of appreciation by the inhabitants of the municipality. Finally, conclusions and future directions of action aimed at improving the quality of services and increasing the attractiveness of urban public transport are presented, thus contributing to the improvement of the quality of life of the inhabitants.

ANALYSIS OF MODERN POPULATION ALERT TECHNOLOGIES IN EMERGENCY SITUATIONS

Serghei Peancovschii — Mon, 15 Jul 2024 00:00:00 +0000

This article explores the factors influencing the selection and development of an emergency population alert system in the Republic of Moldova. An analysis of modern systems in Eurozone countries is conducted, along with a brief overview of their functioning. Here there are identified main factors influencing the choice of modern alert systems. The article also presents an analysis of the advantages and disadvantages of various alert technologies, at the same time it identifies the key requirements for the user interface, including the need for cross-platform software technology.

Eu3+ AS A LUMINESCENT PROBE FOR LOCAL SITE SYMMETRY IN Eu(III) COORDINATION COMPOUNDS

Vladislav Ghenea, Ion Culeac, Artur Buzdugan — Mon, 15 Jul 2024 00:00:00 +0000

The paper deals with the use of tripositive ion Eu3+ as a luminescent probe for the evaluation of the local site symmetry in coordination compounds with europium(III) content. The energy levels of the Eu3+ multiplets in the ligand matrix may be split by the crystal field into a maximum number of 2J+1 components, depending on the site symmetry of the Eu3+ ion. Analysis of photoluminescence spectra provides information on the local site symmetry of the compound. The topic is discussed with reference to literature data as well as own experimental results obtained in the Laboratory of Optoelectronics "A. Andries" of the Institute of Applied Physics. This work gives a deeper insight into the spectral characteristics of Eu3+ ions in ligand matrices and can be a guiding support for investigation of photoluminescence in Eu(III) complexes.

METHODOLOGY AND BACKEND FLOW OPTIMIZATION FOR 3D

Ionica-Marcela Pletea — Mon, 15 Jul 2024 00:00:00 +0000

The article deals with the complexity of the workflow used when integrated circuits are implemented using 2D electronic design automation (EDA) tools and adapting the workflow for 3D integrated circuits. If some issues are not identified promptly in the workflow, the working time to produce an integrated circuit is increased. By analyzing and refining workflow, identifying bottlenecks and early problems in a design, the optimization process will ensure an error-minimized trajectory from synthesis to final design prepared for manufacturing. Considering all the details at every stage of the working flow will help the backend designer to solve problems faster and save time. It was created detailed scripts for automatization of the process at every stage including floorplan, power plan, placement, clock tree synthesis, routing and all physical and logical analysis. The workflow was optimized using loops at all levels, extracting important information at every level and improving the process of working. Moreover, optimization techniques contribute significantly to precision and quality in design implementation. This working flow can be used to implement 3D integrated circuits with automated 2D tools from Synopsis.

RETRIEVAL-AUGMENTED GENERATION USING DOMAIN-SPECIFIC TEXT: A PILOT STUDY

Victor Iapăscurtă, Sergey Kronin, Ion Fiodorov — Mon, 15 Jul 2024 00:00:00 +0000

The natural language processing (NLP) field has witnessed remarkable advancements with the advent of large language models (LLMs) like GPT, Gemini, Claude, etc. These models are trained on vast amounts of text data, allowing them to generate human-like responses for various tasks. However, despite their impressive capabilities, LLMs have limitations in their ability to incorporate and reason over external knowledge that is not in their training data. This limitation of LLMs is particularly evident in the case of specific domain knowledge. This situation has given rise to the concept of retrieval augmented generation (RAG), an approach that combines the generative power of LLMs with the ability to retrieve and integrate relevant information from external knowledge sources. This research attempts to use RAG as a module in an application designed to answer questions concerning a specific domain, namely social philosophy/philosophy of management, using a published book from the respective domain as an external source. The paper analyzes the mentioned application output, draws conclusions, and traces future directions to improve the accuracy of the output.

APPLICATION OF NEW TECHNOLOGIES TO ENHANCE THE STABILITY OF HIGH EMBANKMENT SLOPES

Vladimir Polcanov, Alina Polcanova, Alexandru Cirlan, Alexandru Rascovoi — Mon, 15 Jul 2024 00:00:00 +0000

This study aims to investigate the stability problems of high road embankment slopes in the Republic of Moldova, revealing shortcomings of classical methods. The authors propose a solution by using the RG system, equipped with specialized vibration drilling equipment from "RTG RAMMTECHNIC Gmbh". The method provides for the creation of piles in deep boreholes using the vibrating d, filling the cavities with soil, with subsequent compaction of soil in stages. Experimental field and laboratory research has demonstrated the effectiveness of this method. The results showed significant improvements in soil properties: increased density, strength, and deformation characteristics. The proposed technology offers advantages such as: increased load-bearing capacity of the soil-pile massif, practically complete elimination of dynamic effects on the ground and structures located in close proximity to the construction site, reduced manual labor costs, and a decrease in the overall cost of the construction work. The study aimed the application of this method in Moldova's road construction, highlighting its potential to counteract slope deformations caused by the action of various factors of any nature. The authors suggest the need for further research for refine the methodology, assess economic feasibility, and perform stress-strain analysis using the Finite Element Method. The study was concluded by outlining plans for future research on embankment slopes stabilized by soil piles using the RG installation.

COMPARATIVE ANALYSIS OF THE STRENGTH OF CONCRETE MADE FROM SELECTED ADMIXTURES FOR USE IN RIGID PAVEMENTS

Olufikayo Aderinlewo, Seun Oyeniyi, Moses Ogunsola, Ridwan Alao — Mon, 15 Jul 2024 00:00:00 +0000

This study evaluates the influence of sawdust ash, glass powder and rice husk ash as admixtures for partially replacing fine aggregate in concrete for rigid pavement applications. Compressive strength tests were conducted at 5%, 10%, 15%, and 20% replacement levels. Rice husk ash achieved the highest compressive strength of 10.40 N/mm2 at 10% replacement after 28 days, closest to the control. However, sawdust ash and glass powder exhibited reduced strengths as replacement levels increased. The maximum compressive strength obtained did not meet the required target for rigid pavement applications.

PECULIARITIES OF PROTEINS FRACTIONATION AT ELECTROACTIVATION OF WHEY

Mon, 15 Jul 2024 00:00:00 +0000

Food processing, which generates both by-products and waste, requires a revision of modern processes in the framework of the development of non-residual, environmentally friendly processes. Dairy by-products require the development of complex zero-waste technologies. Electroactivation is an emerging process to overcome those challenges, which allows for non-residual processing of milk by-products. Electroactivation, managing both the technological regimes and the geometric/technical parameters of the electrolyzers used to process different types of whey, allows both the electrofractionation of the whey proteins recovered in protein mineral concentrates enriched, under certain process conditions, with a certain protein content, but also the simultaneous isomerization of lactose into lactulose following two mechanisms, and creating a closed process cycle. The geometry of the electrolyzers and the content of the secondary liquid (anodic liquid) influence both the extraction and the formation of protein compounds enriched with alpha-lactalbumin, as well as the formation of a complex between calcium and isomerized lactulose.

INFLUENCE OF EXTRACTION CONDITIONS ON CONTENT OF BIOLOGICALLY ACTIVE SUBSTANCES FROM POMACE OF CABERNET SAUVIGNON AND RARA NEAGRA GRAPES

Nadejda Botezatu, Ecaterina Covaci — Mon, 15 Jul 2024 00:00:00 +0000

Grape pomace contains many anthocyanins, catechins, flavonoids, phenolic acids, and stilbenes, so it must be utilized. The research used grape pomace from Cabernet Sauvignon and Rara Neagra, harvested in 2023. When creating the absorption spectra, a high content of anthocyanins was observed – components that describe the most significant increases in the spectral line at wavelengths between 510 and 550 nm, specific to these phenolic compounds, confirming the participation of anthocyanins in the formation of the color of grapes as main constituents. Studying the anthocyanin content showed that most pigments that gave the red color were found in acidulated samples of Cabernet Sauvignon, with an extraction temperature of 40°C. The same trend was observed in the acidulated extract of Rara Neagra with extraction temperatures of 40°C and 55°C. When determining the total phenolic content, values ranged between 4.59-5.16 mg GAE/g DW for Cabernet Sauvignon and 4.62-5.98 mg GAE/g DW for Rara Neagra. The antioxidant activity varied in Cabernet Sauvignon between 72.06-86.4%, and in Rara Neagra between 76.79-88.64%. The lowest values were recorded in the non-acidulated samples: 72% for Cabernet Sauvignon and 76.8% for Rara Neagra. As a result, acidulated extracts were the richest in biologically active substances.

HEALTH RISKS FROM TOXIC CONTAMINANTS FORMED DURING THE PROCESSING OF VEGETABLE OILS AND FATS

Angela Gurev, Veronica Dragancea, Raisa Druta — Mon, 15 Jul 2024 00:00:00 +0000

The purpose of this review was to summarize current research findings and unify ideas regarding methods to reduce the health risks to consumers posed by toxic contaminants, such as chloropropanols, glycidols, and their esters, which are formed during food processing, particularly during the refining of vegetable oils and fats, thereby critically impacting food safety. The review describes various aspects related to the occurrence of foodborne toxicants, it covers hazard characterization, their formation mechanisms, and control and regulatory strategies developed in recent years by the World Health Organization, the European Union Commission, and the Food and Agriculture Organization. Additionally, it concludes with an analysis of factors that favor the formation of toxic contaminants in food and discusses some methods for mitigating and monitoring the concentrations of precursors in raw materials. The material is also addressed to researchers, nutritionists and specialists in the domestic food industry, who should pay more attention to the health risk posed by oil and fat processing contaminants and methods of their removal from the raw material.