Változó könyvtárak, változó feladatok: Az „Útmutató könyvtáralapításhoz 3.” ismertetése

SzemletanulmánySzékelyné Török T., Szüts E., Virágos M. (2024) Útmutató könyvtáralapításhoz 3.: gyűjteményszervezés, digitalizálás, nyílt hozzáférés, ELTE BTK Könyvtár- és Információtudományi Intézet, Budapest.https://doi.org/10.21862/utm_kvta_3

Performance Evaluation of a Plug-in Hybrid Powertrain on Compression Ignition Engine in Terms of Energy Consumption Using Intelligent Cruise Control

One of the contemporary trends is to emphasize the benefits of using hybrid drives over conventional ones. Due to the growing popularity of this category of drives, research on the optimization of energy consumption is becoming increasingly popular. The paper presents research on a selected plug-in hybrid drive unit of one of the most popular vehicle manufacturers in the European Union. The research process itself was based on the assessment of the use of active DISTRONIC cruise control as a tool that can influence the optimization of energy consumption of the tested drive unit. The experiment was conducted in real road conditions. Analyses were carried out for several drive system configuration modes: hybrid, E-mode, E-save and charging. The results of the experiment indicated the most optimal drive setting mode on expressways. These analyses emphasize the significant role of intelligent systems as a tool that allows for the optimization of energy consumption of vehicles equipped with plug-in hybrid units. The presented research is dedicated to users of this category of vehicles, while at the same time providing an answer to the question of how to effectively use the described drive unit in real operating conditions

Current trends in library and information science in the light of PhD research and studies – 1.: Interview with Etele Szüts

The editorial team of CELISR conducted a short interview with recent graduates of the Library and Information Science doctoral program at the ELTE Doctoral School of Literary Studies, in order to provide the journal’s readers with an insight into the current and future scientific activities of researchers, and to give an idea of the current research trends in thefield. The following article contains a brief overview of the PhD research conducted by Etele Szüts, Director of the Hungarian Library Institute, with background and future prospects

Response Spectrum of Piecewise Linear Elastic Structures

Response spectra are helpful in the structural engineering practice for the design with earthquake as an extreme load case. However, it is restricted to the linear analysis, except for the plastic behavior. The linear analysis uses a single stiffness only, and by this, the low-level nonlinearities, as the opening and closure of cracks in reinforced concrete structures, are neglected. In this paper, we investigate single-degree-of-freedom systems with two linear elastic states. The response of the piecewise linear elastic structure is compared to the linear response for artificial earthquake accelerograms confined to a design response spectrum. The analysis shows that a high difference in the stiffnesses of the two states may result in a considerable increase in the response. At the same time, states with small relative differences in their stiffness have a maximum response below or close to the response of the linear system. Thus, the neglect of the low-level nonlinearity, as the opening and closing of a crack does not affect the assessment of the structure

Advancements in Heat Exchangers for Improved Engine Cooling: A Comprehensive Literature Review

This literature review investigates the dynamic environment of heat exchangers employed in engine cooling systems, exploring advancements and innovations that have shaped the field. The increasing demand for enhanced engine performance, fuel efficiency, and environmental sustainability has propelled research into heat exchanger technologies. The review encompasses a comprehensive analysis of different types of heat exchangers, materials utilized, design considerations, and performance evaluations, with a keen focus on their respective applications in engines and radiators. The various kinds of heat exchangers belong to the most important themes, such as air-to-air, liquid-to-liquid, finned-tube, and plate heat exchangers, with a focus on their respective advantages, drawbacks, and applications. Design considerations encompass size, shape, and configuration, addressing the factors influencing design choices in modern engine cooling systems. A comprehensive evaluation of heat exchanger performance is carried out, taking into account variables including energy consumption, pressure drop, and heat transfer efficiency. The review incorporates insights from experimental methods and simulations used in assessing heat exchanger performance. Challenges in the field are discussed, providing a nuanced understanding of current limitations, and potential areas for improvement are explored. The literature review concludes with a synthesis of key findings, emphasizing the current state of knowledge in heat exchangers for engine cooling. The abstract aims to provide a concise overview of the multifaceted aspects covered in the literature review, offering valuable insights for researchers and engineers in the advancement of engine cooling systems

Estimation of the Constitutive Relationship between Impact Resistance and Compressive Strength in Sandstones

A series of experiments were performed to investigate the relation between the impact resistance and the compressive strength of sedimentary rocks. The experiments were conducted by the use of Charpy hammer. As a result of these series of experiments an analytical relation was elaborated between the impact resistance and the compressive strength of sedimentary rocks. An envelope domain is presented as an upper and lower bound for this relation, respectively. In the case of the samples, regardless of temperature and saturation states, the impact work values fell within the range bounded by these limit lines (two straight lines). This makes it possible to obtain an estimated strength value by the help of the tests performed in this way only by determining the density and impact work. Measurements performed at different temperatures and saturation states showed that the temperature of the sample at temperatures between −12 °C and 20 °C only minimally affects the result. The water saturation of the sample has a much greater effect on the impact resistance

Influence of Infrared Radiation of Drying Characteristics, Total Phenolic Content, Antioxidant Capacity and Color Properties of Pomegranate Seeds

The aim of this research is to analyze the drying behavior, antioxidant properties, total phenolic content (TPC), and color alterations of pomegranate seeds subjected to infrared drying at temperatures ranging from 55 °C to 75 °C. Analysis of the data revealed a declining-rate drying phase without evidence of a constant-rate phase. The drying rate and duration were found to be directly proportional to the infrared temperature applied; higher temperatures led to faster drying and reduced drying times. The drying process of pomegranate seeds in thin layers was investigated using twelve mathematical models. Among these models, the one presented by Aghbashlo et al. was determined to provide the most precise representation of the drying kinetics. The effective moisture diffusivity values varied between 8.76 × 10−10 and 1.96 × 10−9 m2/s, depending on the temperature range under consideration. Additionally, the activation energy was computed to be 59.37 kJ/mol. The range of TPC values in dry samples fluctuated from 6.19 to 8.20 mg gallic acid equivalent (GAE)/g of dry matter. The 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and copper-reducing antioxidant capacity (CUPRAC) values varied between 5.57–6.13, 24.18–28.18, 10.33–17.59 TE/g dry matter, respectively. The range of ΔE values for the total color change fell between 3.96 and 9.19. Bioactive compound degradation in samples dried at high drying temperature (75 °C) is higher than in samples dried at 55 and 65 °C. When all the results were evaluated, it was determined that 55 °C was suitable for infrared drying of pomegranate seeds

Metamodel-based Optimization of Anisotropic Rotor Axial Flux Permanent Magnet Synchronous Motors

Axial flux motors have some significant advantages over radial flux motors in high torque-density applications. However, the optimization of axial flux permanent magnet synchronous motors is a challenging task; the analysis usually requires 3D finite element analysis or the application of the 2D multi-slice method. In this paper a novel single-surrogate multi-slice method (SS-MSM) is proposed for modeling anisotropic rotor axial flux permanent magnet motors. However, the general methodology can be applied to other axial flux motors as well. A model calibration methodology has been described where the SS-MSM parameters have been determined using a 2D finite element approach as a reference. The SS-MSM was found to be suitable for a fast and reasonably accurate approximation of the motor performance. Based on the described analysis method, an efficient optimization approach is proposed

A Zágrábi Nemzeti és Egyetemi Könyvtár magyar nyelvű gyűjteménye

The National Library of Zagreb is the second largest library in Croatia. It is also a university library, and as such, it also meets the needs of the students of the Hungarian Department in Zagreb. The Hungarian Department Library began to flourish with the move to the new building, and today the collection comprises some 5,000 titles and 860 periodicals, which is currently being expanded.A Zágrábi Nemzeti Könyvtár Horvátország második legnagyobb könyvtára. Az intézmény egyben egyetemi Könyvtár is, ebben a minőségében igyekszik kielégíteni a zágrábi Magyar Tanszék hallgatóinak igényeit is. A magyar tanszéki könyvtár felvirágozása az új épületbe való költözéssel kezdődött, a gyűjtemény ma kb. 5000 címszót és 860 folyóiratot foglal magában, gyarapítása jelenleg is aktívan zajlik