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Pollack Periodica
Authors: Mohammad Alzghoul, Sebastian Cabezas, and Attila Szilágyi

Abstract

The aim is to derive an expression to calculate the natural frequencies and plot the mode shapes of a simply-supported beam with an overhang with an end overhang point mass by using the Euler-Bernoulli theory in the case of free transverse vibrations. The results are validated by finite element analysis. The importance of the system presented is that it can represent machine tool spindles or even machining tools like boring bars. The results are in good agreement with the results from the finite element analyses. The derived expression can be used in optimizing the value of the point mass and optimizing the support location for better performance of the system without the need to perform complex analysis to obtain the values of the natural frequencies and to plot the mode shapes.

Open access

Abstract

In this research work existing laboratory tests of slim floor beams with solid monolithic concrete slab were modeled and analyzed using GID and Atena software. After validating the advanced finite element model with the test results of the international literature, structural parameters were analyzed with the aim to study their influence on the load bearing and deformation capacity of the beams. The parameters were related to the geometric of the beam: size of web openings and top concrete cover. With these results conclusion can be noticed that focusing on the optimal arrangement of the geometrical parameters of the composite beam could lead to better structural behavior with more economical solutions.

Open access

Abstract

The optimization of high-rise office buildings' envelope and the application of energy-efficient measures have become a priority nowadays. Therefore, this investigation aims to assess the role of the façade's geometry design factors, e.g., folded façade perforation, window orientation, and window-to-wall ratio on building comfort and energy performance. The energy simulations were performed using IDA ICE 4.8 thermal simulation program to evaluate the thermal and visual comfort and the energy consumption of various façade test models. The optimization resulted in a façade model with a great level of thermal and visual comfort as well as a total energy reduction of 14%, representing a good compromise solution in the trade-off between thermal and visual comfort as well as energy efficiency.

Open access
Pollack Periodica
Authors: Patrik Márk Máder, Olivér Rák, Nándor Bakai, József Etlinger, and Márk Zagorácz

Abstract

Nowadays, it is increasingly important to develop economical construction processes and determine predictable costs. The current level of technology offers countless, even undeveloped opportunities to support architectural, engineering, and construction processes. Building information models created as results of design processes and databases associated with them can provide an appropriate base to fulfill the requirements. However, this information is mainly available only for the largest projects; the possibilities offered by traditional editable vector files (e.g., *.DWG) should also be examined. This study analyzes the efficiency increasing possibilities that can be achieved using low-detail 3D models generated by algorithms and applying 2D-based digital quantity estimation workflows.

Open access

Abstract

Frame structures are defined as structures built of straight, less often curved bars, which are dimensioned to carry a planar or spatial load. These frames are generally considered statically indeterminate structures so that several methods can be used to determine their loads, but all of them require some simplification. This paper is not concerned with investigating these theories for determining the stresses but with the optimum design of a frame structure for a given geometry. Several different loads have been considered, where the value of the wind load in the horizontal direction has been considered. The optimization problem is mathematically formulated so that both compressive forces and bending moments acting on the horizontal beam and the vertical column, and their composite loads, are below the limit set by the material properties. The column connections were assumed to be fully rigid, and welded I-section were considered for both columns. For local bending conditions, the Eurocode 3 specification was applied. Several steel grades were tested during the investigations, and fire loading was considered an additional load. In this case, a higher safety factor was assumed to make the times to collapse comparable.

Open access
Pollack Periodica
Authors: Hui Cao, Anna Mária Tamás, Gergely Sztranyák, and Erqing Zhang

Abstract

Vernacular architecture is the source of the historical development of architecture and the carrier of traditional culture. It is also the emotional sustenance of contemporary Chinese people’s beautiful homesickness. With the rapid expansion of urbanization in China, a widespread phenomenon of “hollow villages” has emerged in rural areas, and there are many abandoned rural buildings all over the countryside. Therefore, the protection and sustainable development of rural architecture are imminent. Based on the author’s rural construction project in China, this research integrates environmental psychology and architecture and tries to build a high-quality living environment, aiming to explore a new design strategy to meet the challenges in the future.

Open access

Abstract

Because of thin wall thicknesses and closed bottom ends of the extruded aerosol can, the necking limit analysis needs intensive investigation. The numerical analysis of the necking process of 0.45 mm thickness pure aluminum aerosol can was carried out. The result indicated that the length of the aerosol can wall, which is not fixed by the bottom die and the angle of inclination of necking tools are important factors that affect the development of deformation boundary limits due to plastic instability of local buckling. The fraction of taper angle of tool becomes more series parameter while necking at larger free length and it needs more concentration. Instead, the ratio of necking tool displacement to the total free length to initiate buckling was increased while increasing free length.

Open access

Abstract

China has a lengthy and glorious history spanning thousands of years. Traditional dwellings represent distinct regional cultural origins, and different forms of housing constructions have arisen as a result. However, traditional dwellings preserve area culture and specific life memories as a fundamental component of rural life. From the perspective of conventional dwellings, this paper takes the representative Manchu folk houses in Northeast China as an example. It discusses the architectural structure, appearance style, and overall style of Manchu folk dwellings and the cultural dimension of architecture and its distinctive value under the impact of regional culture.

Open access

Abstract

In this work, the properties of mechanochemically produced (by using mills made from different materials) barium-titanate (BaTiO3) and zinc-titanate (ZnTiO3) perovskites are compared. Mechanochemistry is a process that can cover the energy demand of some reaction pathways between solid materials. This process is called “high-energy milling”, for which not all types of mills are suitable. In our case, a planetary ball mill provided the necessary energy. Using a model, the required energy is determinable; the energy released during an impact of a milling ball (E b – ball-impact energy), as well as during the whole milling (E cum – cumulative milling energy). Thus, a milling-energy map was created, with which the applied E b and E cum values were visualized depending on the different grinding parameters. The parameters changed were the material of the grinding vessels, the number of grinding balls, and the rotational speed. The transformation was tracked by X-ray diffraction (XRD) measurements, and electron microscopic images (TEM and SEM) of the perovskites produced were taken. This study aimed to draw conclusions that will help later in the synthesis of materials with other perovskite structures by choosing optimal milling parameters.

Open access

Egy köles tájfajta műtrágya-reakciójának vizsgálata

Examination of the reaction to fertilization of regional millet variety

Agrokémia és Talajtan
Authors: Zsembeli Zsadány, Sinka Lúcia, Tüdősné Budai Júlia, Kovács Györgyi, Tuba Géza, and Zsembeli József

Kutatómunkák általános célja olyan kísérletek végzése, amelyek feltárják az adott régióban perspektivikusan termeszthető fajták, illetve tájfajták optimális műtrágyázási igényeit. Tanulmányunkban a Karcagon nemesített és fenntartott ’Maxi’ köles tájfajta tápanyagreakciójának vizsgálatából származó eredményeinket mutatjuk be a módosított Országos Műtrágyázási Tartamkísérlet (OMTK) 2017. évi és az annak figyelembevételével 2021-ben beállított Műtrágyázási Kísérleti Kert (MKK) adatai alapján. A kísérleteket Karcagon, a MATE Karcagi Kutatóintézetben, egy mélyben szolonyeces réti csernozjom talajon állítottuk be. 2017-ben a módosított OMTK kezelései 4 nitrogén (40, 80, 120, 160 kg ha 1), 4 foszfor (0, 40, 80, 100 kg ha 1) és 3 kálium (0, 60, 90 kg ha 1) dózis kombinációjából adódtak, illetve volt egy műtrágyázás nélküli abszolút kontroll. 2021-ben az MKK kezelései 3 nitrogén (40, 80, 120 kg ha 1), 3 foszfor (0, 40, 80 kg ha 1) és 2 kálium (0, 60 kg ha 1) dózis kombinációját foglalták magukba, illetve mindegyik parcella felére növénykondicionáló szert juttatunk ki. A termesztett növény mindkét évben a karcagi nemesítésű ’Maxi’ kölesfajta volt. A különböző kezeléscsoportok termésre gyakorolt hatásának statisztikai értékelését egytényezős varianciaanalízissel végeztük el. Mindkét vizsgálati évben a 80 kg ha 1 hatóanyag mennyiségben kijuttatott nitrogén műtrágyázás bizonyult a leginkább megfelelőnek. A magas foszfor dózisok a legtöbb esetben termésdepresszióhoz vezettek. Eredményeink alapján még a közepes – jó kálium ellátottságú karcagi talajokon is hasznos lehet a kálium kijuttatása, bár a káliumtrágyázás termésre gyakorolt hatását a varianciaanalízis nem igazolta. Az Algomel PUSH szerrel végzett növénykondicionálás statisztikailag is igazolhatóan, mintegy 10%-kal növelte a termés nagyságát. Kutatómunkánk folytatásával pontosabban meghatározható lesz számos tájfajta tápanyagreakciója és fajtaspecifikus, a helyi agroökológiai viszonyokat is figyelembe vevő tápanyag dózisok és kombinációk ajánlhatók a gazdálkodóknak.

The general objective of our research is to carry out experiments that are suitable to reveal the optimal fertilization demand of regionally bred or potentially producible crop varieties for a specific region. In our recent study, the results gained from the examination of the nutrient reaction of the regional millet variety ‘Maxi’ bred and maintained in Karcag are introduced based on the data originating from the modified Long-term National Fertilization Experiments (OMTK) in 2017 and from the Fertilization Experimental Garden (MKK) established at Karcag in 2021. Both experiments were set up in the MATE Research Institute of Karcag on a meadow chernozem soil salty in the deeper layers. In 2017, there were 4 nitrogen (40, 80, 120, 160 kg ha−1), 4 phosphorus (0, 40, 80, 100 kg ha−1), and 3 potassium (0, 60, 90 kg ha−1) dosage combinations applied and one unfertilized absolute control in the OMTK trial. In 2021, in the MKK experiment, treatments involved 3 nitrogen (40, 80, 120 kg ha−1), 3 phosphorus (0, 40, 80 kg ha−1), and 2 potassium (0, 60 kg ha−1) dosage combinations, furthermore, on half of the plots a plant conditioner was sprayed. Millet variety ‘Maxi’ bred at Karcag was the indicator crop in both years. For the statistical analysis of the effect of the various treatment groups on yields, One-way ANOVA tests were used. We considered the 80 kg ha−1 nitrogen substance dose the most suitable in both years. High dosage of phosphorus application resulted in yield depression in most of the cases. Based on our results, potassium fertilization can be effective even on the soils of Karcag with medium to good potassium supplies, though the analysis of variance did not justify the effect of K-fertilization on yields. The 10% yields increase due to plant conditioning with Algomel PUSH was statistically proven. By continuing or research, the reaction to fertilization of several regional crop varieties can be determined more precisely, and variety-specific nutrient doses and combinations can be determined and suggested to the local famers taking the regional agri-ecological conditions into consideration.

Open access