Periodica Polytechnica (Budapest University of Technology and Economics)
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The Role of University Training in Addressing Challenges in International Employment
No full textThe study investigates the impact of higher education on preparing Malaysian students for employment on a global scale, emphasizing the need for academic curricula to align with global labor market needs. Using a systematic literature review protocol, studies were included based on their relevance, currency and academic impact. This research draws upon existing work with respect to professions, the labour market, higher education policy, and global skills needs. It further presents a snapshot overview of Malaysia’s tertiary education system, comprising of the three main types of tertiary institutions (public institutions, private institution, religions owned institutions, foundation charted institutions) highlighting their uniqueness in preparing students for international careers. Using a quantitative methodology, we surveyed 400 students at 20 universities (10 public and 10 private), achieving a decent representation in terms of institutional diversity. The criteria for selection included selection based on rankings of the institutions, the diversity of academic programs, and employment rates of graduates. The key areas of analysis included curriculum relevance, development of soft skills, global exposure, and challenges in international employment. Results show that although institutions of higher education have embraced global ideas, issues like language obstacles, lack of career guidance, and monetary limitations continue to exist. Moreover, the religious and cultural considerations inform curricular content and influence students' perception of employability, especially in religious institutions. The methodological strengths and limitations are further discussed, highlighting the importance of broader sample representation and longitudinal studies to follow-up on employment outcomes. It also concludes with recommendations for enhanced curriculum, stronger links between universities and industry, and improved support services for students to improve employability prospects worldwide
Gondolatok a piaci kereskedelem fejlesztésének szükségszerűségéről, lehetőségeiről és esélyeiről : Budapest élelmiszerkereskedelmét befolyásoló legfontosabb folyamatok áttekintése
No full textThe evolution of food retail processes over the past 15–20 years has been dynamic, with fundamental changes occurring in certain areas. Today, traditional marketplace food retailing coexists with so-called small local shops in towns and villages, alongside newly emerged multinational food retail chains operating hypermarkets and supermarkets. With the recent separation of offline and online commerce, e-commerce has also taken a prominent position in the food retail sector. The transformation of commerce has been ruthless in some areas, delivering particularly harsh blows to traditional food markets. This trend is observable internationally as well, although the commercial development policies of major European cities—especially regarding multinational food chains—have often differed from domestic practices.
The first part of this study aims to present several currently valid theoretical issues underlying food retailing and, through analytical methods, examines the competitiveness of traditional marketplaces and market halls. The study investigates the components that determine the survival prospects of markets and market halls in the capital city, their added value compared to competing commercial players, and attempts to formulate a development strategy through which a potential development project could ensure the continued functionality of Budapest’s traditional market halls and the future survival of various food markets. The analysis is fundamentally rooted in the necessity of preserving traditional food markets, which are based on a millennia-old commercial culture built around meeting consumer needs, while also serving as valuable and significant venues for social interaction. The second part of the study will expand on the processes currently influencing Budapest’s food retailing landscape and the evolving positions within the commercial sector.
The first part of the study titled Reflections on the Necessity, Possibilities, and Prospects of Developing Market-Based Commerce (Opus et Educatio, Volume 12, Issue 2) provided a general overview of the food retail positions of traditional markets and market halls, along with the advantages and disadvantages they face in comparison to newly emerged competitors such as multinational food chains and e-commerce platforms, and evaluated their developmental opportunities.
In the second part, the current practical experiences of food retail in Budapest are analyzed. The study includes an evaluation of the differences between in-person (offline) and e-commerce (online) channels, the significance of various commercial functions, their transformations, and their impact on different types of markets in Budapest (traditional, organic, eco) and the future status of market halls.
The analysis also quantifies and interprets changes in consumer demand in the capital, the demographic developments of different districts, the number of stores operated by food chains, and the changes in the number of still-operating markets and market halls. It compares the prices of several products across various food chains and selected market halls, revealing the current static or dynamic pricing strategies of different retail sectors, the prospects for future pricing mechanisms, and consequently, the risks facing traditional market-based commerce.
The study addresses the delicate economic conditions of primary producers with deep-rooted traditions in the food retail market and the social consequences of their gradual exclusion from market trading opportunities. The concluding section highlights the necessity of a comprehensive food retail concept for Budapest’s markets and outlines the potential content of such a strategy.Az első részben arra kerestem a választ, mi jellemzi elméleti megközelítésből a kereskedelem működését, milyen új folyamatok játszódtak le az elmúlt 15-20 évben, mi jellemzi napjaink kereskedelmi technikáit, hogyan tudna versenyben maradni a hagyományos piaci élelmiszerkereskedelem a konkurens élelmiszerláncok kereskedelmi technikáival szemben, mi az a hozzáadott érték, ami a hagyományos piacokon, vásárcsarnokokban ma még felfedezhető és megőrzésre vár. A piacokra és csarnokokra vonatkozó analízis után a piaci kereskedelem jövőbeni fejlesztési stratégiájára és egy projekt elemeinek felvázolására tettem kísérletet az előző részben.
A második részben a jelenlegi állapotok feltárása és bemutatása a cél. Budapesti élelmiszerkereskedelem taglalásánál azokat az összefüggéseket és adatokat vizsgálom meg, amelyek a főváros kerületeiben működő piacok, vásárcsarnokok, valamint a különböző élelmiszerláncok üzleteinek számát, azok eloszlását mutatja be. Ezt követően a lakosság élelmiszer beszerzési döntéseit nagyban meghatározó fogyasztói árak alakulását vizsgálom néhány gyakori élelmiszernél, amelyek mindegyik vizsgált kereskedelmi területen megtalálhatók és így azok egymáshoz való viszonya befolyásolhatja (más fontos tényezők mellett) az egyes kereskedelmi egységek jövőbeli perspektíváit is. (Az első részben elméleti és gyakorlati összefüggésekkel, az élelmiszervásárlást meghatározó egyéb területekkel, tényezőkkel is foglalkoztunk.
Creating Smart Packaging Film with Garcinia Mangostana L. Pericarp Powder for Fish Fillets Monitoring
Get PDFEnsuring the freshness of food products is a critical factor influencing consumer perception and acceptance, which directly relates to food safety and quality. To support responsible consumption and minimize food waste, this study introduces smart packaging technology designed to monitor the freshness of perishable goods. Specifically, smart packaging films were developed by incorporating mangosteen pericarp powder (MPP) and anthocyanin extract (ATH) from Garcinia mangostana L. to assess the freshness of fish fillet. Among the formulations, the starch-MPP film demonstrated superior pH sensitivity, making it more suitable as a smart packaging indicator due to its distinct color change response. Furthermore, the starch-MPP film exhibited the highest antioxidant activity at 96.88%, compared to the Starch-ATH film (85.83%), contributing to the preservation of food quality. When applied to fish fillet stored at 5 °C for two days, the starch-MPP film showed visible color shifts in response to pH changes caused by the release of nitrogenous compounds, indicating spoilage. This underscores the potential of starch-MPP films as an eco-friendly innovation for real-time freshness monitoring, contributing to both public health and sustainable food systems
Modeling and Experimental Study of Liquid–liquid Extraction of Water + Formic Acid + 1-Octanol with NaCl and KCl Using Non-random Two-liquid and Artificial Neural Network Models
Get PDFThis study investigates the liquid–liquid extraction behavior of a ternary system composed of water, formic acid, and 1-octanol in the presence of inorganic salts (NaCl and KCl) at varying concentrations of 0%, 5%, 10%, and 15%. Each salt was examined individually to assess its impact on the extraction efficiency. Experimental solubility data and tie-line compositions were obtained. The results demonstrate that the addition of salt significantly improves the efficiency of extraction. NaCl was found to induce a stronger salting-out effect than KCl, especially at 10% concentration, where the highest selectivity and distribution coefficient were observed. To model the phase behavior, both the Non-Random Two-Liquid (NRTL) thermodynamic model and an Artificial Neural Network (ANN) were employed based on the experimental results. A Neural Architecture Search approach was implemented to optimize ANN structure. Both models exhibited strong predictive capability; however, the ANN model demonstrated superior performance, achieving higher accuracy and lower prediction errors than the NRTL model, particularly at high salt concentrations
Modified Correlations to Predict Shear-wave Velocity Using Cone Penetration Test Data for Hungary
Get PDFThis study evaluates and optimizes empirical correlations between shear wave velocity (Vs) and cone penetration test (CPT) data for various soil types in Hungary. A comprehensive database of 914 data pairs was compiled from multiple cities with diverse geological conditions, incorporating SCPTu and MASW measurements. Over 40 existing Vs–CPT correlations were statistically assessed using parameters such as RMSE, RD, K, CVK, and RI to determine their accuracy across different soil types and depositional settings. The most promising correlations were further refined using regression analysis, leading to the development of improved models tailored for Hungarian soils. These new correlations were evaluated both graphically and statistically, showing enhanced predictive performance, particularly for coarse-grained soils. The final proposed models demonstrate significant reductions in estimation error, with RMSE improvements exceeding 35%. This work provides geotechnical engineers in Hungary with robust, site-adapted tools for seismic site characterization and supports safer and more reliable subsurface profiling practices
An Integrated Time-frequency Framework for Cable Force Identification in Long Cables of Long-span Bridges
Get PDFAccurate identification of cable forces is crucial for the Structural Health Monitoring (SHM) of long-span cable-stayed bridges. However, vibration-based methods face significant challenges when analyzing closely spaced high-order frequencies in long cables, including the difficulty of identifying low-order frequencies and the propensity for modal aliasing. This paper proposes a novel integrated time-frequency analysis framework to automatically identify cable frequencies from vibration data without prior information. The framework employs a hierarchical approach where the Secondary Fourier Transform (SFT) first automatically estimates the fundamental frequency difference, thereby enabling two advanced techniques: the modified short-time Fourier transform (MSTFT) for sparse modal identification and the modified Hilbert transform (MHT) for high-precision instantaneous frequency (IF) tracking. Several long cables in a certain long-span bridge were employed, and the results demonstrated that the framework successfully identifies cable frequencies from higher-order modes (10th to 15th order), effectively compensating for weak low-order signals. SFT provided a rapid and robust estimation of the average frequency difference. Building on this, MSTFT enabled the sparse frequency identification of designated modal orders, while MHT precisely captured IF fluctuations, revealing dynamic force changes that correlated with peak traffic periods. The proposed integrated framework offers a powerful and adaptable solution for cable force identification. The proposed framework automates the analysis, mitigates modal aliasing, and accommodates multi-precision requirements. This enhances traditional vibration-based monitoring, delivering a robust solution for SHM systems to better assess operational safety and optimize the maintenance of long-span bridges
On the Long-term Deflection Behavior of Timber–concrete Composite Slabs
Get PDFThis paper investigates the long-term behavior of cross-laminated timber (CLT)–concrete composite (TCC) slabs through a large-scale parametric study using a two-layer finite-element model with interface springs to represent partial interaction. The study isolates the influence of four parameters—concrete shrinkage (modeled via relative humidity, RH), composite factor (γ), concrete creep coefficient (φ), and timber creep coefficient (Kdef)—on time-dependent deflections. A total of 36,864 analyses were performed for a 6 m span under quasi-permanent loading, with results normalized to the least-deflecting case in each subset.For a representative configuration (CLT 120 mm, concrete 50 mm) and RH = 60%, the normalized 50-year deflection increases by approximately 22% with higher shrinkage, by 6% when reducing γ from 0.9 to 0.3, by 8% when increasing φ from 1.5 to 3.0, and by 12% when increasing Kdef from 0.6 to 1.0. Across configurations, shrinkage is consistently the dominant driver. Moreover, shrinkage-induced deflection scales approximately linearly with the distance from the centroid of the concrete layer to the composite neutral axis (Zna), highlighting geometry as a primary design lever.The design implications are as follows: 1. prioritize low-shrinkage concrete mixes; 2. avoid intentionally reducing γ, as global stiffness and overall performance deteriorate; and 3. select layer proportions that minimize Zna while balancing the stiffness gains and shrinkage sensitivity associated with thicker concrete toppings
Post-Grouting Behaviour of Ground Anchors in Dense Cohesionless Soils: Field Observations and Theoretical Insights
Get PDFPost-grouting is a widely adopted technique in ground anchor systems intended to enhance grout–soil interaction through pressure-induced mechanisms. It is generally assumed to improve load transfer by inducing fissures in the initially set grout, expanding the grout body, and enlarging the fixed-length diameter. This study investigates grout behaviour under post-grouting pressure in dense cohesionless soils using data from 870 post-grouted anchors installed at nine construction sites in Budapest, Hungary, with similar ground conditions. Grouting volumes were statistically analysed, focusing on the correlation between grouting volumes and their relationship to soil properties particularly grain size distribution. Theoretical grout body diameters were estimated using expansion and infiltration models. Load–displacement test data were used to back calculate apparent free lengths and infer fixed lengths, which were compared with literature values. Two post-grouted test anchors were excavated. Both showed uniform diameters matching the original borehole, with no signs of grout body enlargement. However, large irregular grout masses were found in permeable zones, suggesting material migration toward weaker paths under pressure. These findings indicate that in medium dense to dense sands, post-grouting enhances performance primarily through local soil densification not geometric expansion, highlighting the need to revise traditional assumptions regarding grout behaviour in such conditions
Validity of the TRINCA Model (1988) in Current European Road Safety Assessment: A Comparative Study Using Recent Data
Get PDFRoad safety is a growing concern in Europe, with significant changes in traffic conditions, vehicle technology, and safety regulations over the past decades. The TRINCA model (1988) was historically effective in assessing road safety through two key indicators: Personal and Road Safety. However, its validity in the current context has become questionable due to evolving road safety measures. This study examines the applicability of the TRINCA model using recent data from 27 European countries for the years 2005, 2010, 2015, and 2020. Countries were divided into four geographical regions, and a T-test analysis was performed to compare the observed data against the model's predictions. The results reveal significant discrepancies, particularly after 2015, with P-values indicating statistically solid significance (P ≤ 0.05 to P ≤ 0.001). These findings suggest that the TRINCA model no longer accurately represents current road safety trends and highlights the need for an updated framework incorporating recent advancements in vehicle technology, infrastructure improvements, and updated traffic regulations