Discover the Latest Journals in Architecture and Architectonics
Architecture is both the process and product of planning, designing, and constructing a building or structure, while architectonics is the scientific study of architecture itself. Architectural works are often considered important cultural symbols and works of art, and we often identify past civilizations with their architectural heritage.
Architecture and Architectonics
Abstract
Cement production generates nearly one ton of carbon dioxide for every ton manufactured, contributing significantly to environmental degradation. Geopolymer concrete, which incorporates industrial by-products, for example, fly ash, metakaolin, and ground granulated blast furnace slag, offers a sustainable alternative. This study explores the use of stone quarry dust as a replacement for natural sand in brick production. A blend comprising 70% metakaolin, 30% ground granulated blast furnace slag, and stone quarry dust, activated with sodium silicate and sodium hydroxide, yielded bricks with high compressive strength, minimal water absorption, and excellent acid resistance. These eco-friendly bricks provide a cost effective, durable alternative to conventional bricks, making them suitable for diverse environmental conditions.
Abstract
The paper focuses on the creation of 3D models of indoor building environments. The data for model creation is acquired using a developed mobile mapping system, which consists of a combination of various sensors. It includes a trio of 2D and 3D light detection and ranging unit, an inertial measurement unit, a stereo camera, and rotary encoders. The collected data is processed using simultaneous localization and mapping through a graph-based approach. The quality of the created 3D model is numerically quantified.
The first part of the paper describes the developed mobile mapping system, which comprises three subsystems. The next section explains the processing of the collected data using simultaneous localization and mapping. The quality of the created 3D model is subsequently analyzed. The final section evaluates the results and outlines future objectives of the research.
Abstract
This study experimentally investigates a natural gas-diesel dual-fuel naturally aspirated engine's combustion and emissions under low to high load and constant engine speed. The natural gas is supplied with constant pressure at the intake manifold through an air-gas mixer. A mechanical high-pressure fuel injection pump automatically controlled the diesel fuel. Results indicate that using natural gas reduced diesel fuel consumption, CO2, smoke, and NOx emissions, but increased CO emission with different values according to engine load. As well, in-cylinder pressure and heat release rate are influenced by using natural gas and changing engine load. These results differ from prior research; therefore, this study could be a basis for future research on hydrogen-natural gas blends.
Abstract
The current investigation shed light on examining the properties of ceramic based composites manufactured with various percentages of alumina and zirconia. Compressive strength, volumetric shrinkage, apparent porosity, and apparent density of the ceramic composites were the most significant outputs that impacts the composites quality. Therefore, this paper aims to evaluate the resulted composites according to these outputs' response. It was noted that the dominant peaks in the X-ray diffraction results is tetragonal zirconia in spite of using monoclinic zirconia during the composites manufacturing. The optimum compressive strength of 370 MPa was emerged with specimens after sintering produced with 70 wt.% zirconia and 30 wt.% alumina. Moreover, the zirconia-alumina composites findings revealed a remarkable improvement when compared with ceramics made from these materials individually.
Abstract
This work aims to numerically study a latent heat storage system consisting of a tank filled with a phase change material, through which a heat transfer fluid flows. A comprehensive parametric study was conducted to analyze the thermal and dynamic performance of the system, examining the effects of various parameters, including tank height, heat transfer fluid mass flow rate, phase change material layer thickness, and the amount of energy stored during the charging process.
The system was modeled using computational fluid dynamics to simulate the phase change phenomena. It was seen that a higher mass flow rate led to a shorter storage time and reduced stored energy, with values of 19.25 kWh for a flow rate of 0.6 kg s−1 and 20.16 kWh for a flow rate of 0.4 kg s−1.
Abstract
Delivering Advanced Driver Assistance System functionalities depends on acquiring high-resolution image data from vehicles. Adverse weather and nighttime degrade image quality, impacting object detection accuracy. This paper addresses this issue by proposing a novel solution using the vehicle's Global Positioning System location and timestamp to query weather via a weather application programming interface. By obtaining weather details at the time and location of data collection, image quality is enhanced through pre-processing tailored to specific weather conditions. Using the Detection in Adverse Weather Nature dataset, the method improves You Only Look Once version 8 software detection accuracy by up to 15% compared to baseline performance across various weather conditions, enhancing Advanced Driver Assistance System reliability.
Abstract
As a result of global warming, Hungary's climate characteristics are shifting towards hot, dry conditions, for which the local building stock is not prepared. The research focuses on the effectiveness of the application of the “secondary building skin”, a passive architectural solution that supports to create the required thermal comfort in buildings. The applicability of the solution is supported by measurements and simulations, combining the energy renovation possibilities of Hungarian “cube-type houses” and adaptive technology that migrates with climate. The article examines the reduction of heat load on buildings and its impact on the indoor operative temperature. Also, it shows how the visual appearance of the secondary building skin can become an architectural character element as a tool for sustainability.
Abstract
Due to the transfer of environmental heat into buildings, requires consuming large amounts of electrical energy for absorbed heat gain. This study used sunflower seed husks as one of the industrial residues, as a waste material. These husks were ground into a nano-powder and blended with cement at a weight of 1:5. From this mixture made of 12 mm diameter balls then added back to the building block mix during formation. The thermal behavior of the walls constructed from these blocks was tested in the climate of Baghdad, during daylight hours on the 21st day of each summer month (May – July) in 2022. The optimal addition ratio was 4%, which achieved a heat load of 176.2 kW and an electricity consumption of 110.2 kWh, resulting energy savings of 18.1% compared with a traditional wall.
A kupolák tisztelete
Az egykupolás dzsámik eredete és térhódítása az oszmán építészetben II.
Respect for Domes
The Origin and Spread of the Single-Domed Mosques in the Ottoman Architecture II.
Az oszmán építészet a turisták számára egyet jelent a Kék mecsettel, a szakemberek többsége számára pedig a bizánci építészet, különösen pedig a Hagia Sophia másolásával. Igaz, Bizánc és Konstantinápoly, amely akkor szinte egyet jelentett a művelt világgal, vonzotta és inspirálta is a szomszédságában államot alapító oszmánokat. De volt ezzel így más is, akár tanulmányunk tekintetében szűkebb értelemben a kupolák esetében is. A Földközi-tenger keleti medencéje és a mai Közel-Kelet évezredes hagyományokkal bír a boltozatok és kupolák alkalmazása terén. Különösen igaz ez Iránra, ahol az egyéb építőanyagok híján rákényszerültek ezeknek a szerkezeteknek az alkalmazására és továbbfejlesztésére is. Ez a szeldzsuk birodalomban olvadt össze a nomád törökség kupolatisztelő hagyományaival, és ez az ötvözet termékenyítette meg az oszmán építészetet, amelyet természetesen színesített a bizánci, sőt az itáliai reneszánsz építészet is. Az oszmán szakrális építészet legjellegzetesebb produktuma az egykupolás dzsámi, mely szeldzsuk alapokból fejlődött ki, de már a 14. század első harmadától oszmán alkotásnak tekinthető. Akár önálló épületként, akár összetettebb tér uralkodó elemeként alkalmazzák, az egykupolás dzsámi lesz az oszmán legmeghatározóbb építészeti eleme. Ennek kialakulásával és fejlődésével foglalkozik a jelen tanulmány, mely két részletben olvasható. Az első részt előző számunkban közöltük.
Abstract
Inclined duct has many engineering applications like air conditioning system, solar collector and cooling system of photovoltaic module. Forced convection of air flowing through an inclined square porous duct is described in this paper. The experiments by varying Reynolds number, heat flux and inclination angle have been conducted under Reynolds number at 8355, 13485 and 18600 range, heat flux 480, 990 and 1520 W m−2 and inclination duct angle 30°–60°. The porous pad used was zig-zag metallic wire mesh with porosity equals 0.99. The results show that Nusselt number is increased with increasing heat flux and Reynolds number at all orientations. At the same Reynolds number and heat flux, Nusselt number is enhanced about 4.7% with increasing inclination angle from 30° to 60°. Nusselt number is to be 24%, 21% higher than horizontals porous duct at inclination angle 60°–30°, respectively. Many empirical relations have been obtained.
Abstract
The study aims to develop a predictive model for crack propagation in a blade's plate. The finite element method is employed to simulate the blade's entire structure. ANSYS software is utilized to model the plate and determine its natural frequencies under cyclic loading. The results obtained through the finite element method are compared with data from the literature to confirm the validity of the proposed model. Both natural and forced vibrations of the blade's plate, including double-edge cracks, are analyzed. Various crack sizes and locations are modeled to investigate their impact on the blade's behavior. The proposed model effectively identifies the crack in the plate that forms earlier and achieves a high accuracy in predicting the crack's size and location under cyclic loading.
Abstract
Stress analysis is a branch of mechanical engineering that investigates the stress and strains generated in materials when subjected to forces. Photoelasticity is one of the well-known methods in plane stress analysis. This analysis was conducted to show the superiority of the photoelasticity method in investigating the stresses of the spur gear teeth. Four cases of various spur gear teeth profiles have been presented. The principal stress difference was calculated experimentally for each case and it was validated numerically and the error percentage reached 4.15%. An enhancement percentage was achieved at 33% in case 3 leading to the fact that using the asymmetric spur gear teeth reduces the generated stresses.
Abstract
The in-plane tensile-compressive test is a key method for studying plastic behavior under complex loading. This study presents a novel anti-buckling fixture designed for cyclic testing. The device can conduct monotonic tensile-compressive tests with deformations of up to 10%. The specimen is encased in an acrylic block for structural stability and to prevent buckling. Its application and impact on the force-displacement curve have been addressed. The AutoGrid optical strain measurement system was integrated with the fixture for strain analysis, and its accuracy was systematically evaluated. The developed fixture is well-suited for accurately describing the plastic behavior of materials under complex loading paths and it aids in precisely determining the kinematic hardening characteristics.
Abstract
In a manuscript the results of research of the characteristics of a flat air stream with a variable mode of its flow into the room depending on time and current position are presented. Analytical equations for calculating the flat air jet parameters were derived. Numerical modeling of the incoming air stream in the variable mode was carried out due to CFD FLUENT (ANSYS FLUENT) software using the k–ε turbulence model. Method of a four-parameter numerical simulation of the flat incoming airflow in the variable mode is devised.
Abstract
Amputees pursue to obtain an artificial limb that suits them and adapts as close as possible to their healthy limb, especially for amputees of the lower limbs that are characterized by the necessity of performing the function of walking through the existing joints to make the amputee feel like having a healthy limb and perform its own needs. Here in this research we will address the improvement of the prosthetic limb of the amputee through the ankle joint, as a movable ankle joint was designed for the level of amputation through the ankle joint in the SolidWorks program and the data was analyzed using ANSYS to find out the extent to which the joint is able to perform plantar flexion and dorsal flexion movements and its range of motion by applying them realistically through tests conducted on the amputee when wearing the prosthetic with the hinged ankle joint and simile it with the conventional prosthetic with the fixed joint.
Abstract
Nowadays, aligned with the national mission, the growth of Unmanned Aerial Vehicle (UAV) application is enormous. This research work investigates the probability of adding epoxy resin with novel biofibres such as Tamarindus indica and Morinda citrifolia to fabricate a composite material. A sustainable outcome is delivered by adopting Tamarindus indica and Morinda citrifolia fibres in UAV frame materials, which combine increased mechanical strength and durability with good environmental conditions. Based on the mechanical test outcomes, the Tamarindus indica composite (ETI) indicates significant compressive strength with an optimum load-carrying capacity of 5.98 kN and notable tensile strength is a maximum of 8.13 MPa, therefore Tamarindus indica composite plate can be used in rigid or definite-shaped applications due to its high resistance to deformation. The Morinda citrifolia composite (ETC) indicated high flexibility rate due to carrying a flexural load (0.15 KN), so it can be used as a dampening or cushioning material to absorb the vibrational energy. These two novel biodegradable composite materials possess a lower density and a higher strength-to-weight ratio, which are important properties for decreasing power consumption and improving the UAV's endurance. We investigated the chemical and morphological characteristics of the novel composites using scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). These novel biomaterials significantly reduce vibrations from UAV propellers and metal corrosion. Based on the research outcomes, using novel bio composites increases the mechanical strength and lifespan of UAVs and it also reduces their weight and power consumption.
Abstract
This research presents an experimental program to study the effect of adding brick waste as a replacement for gravel in concrete mixes. Styrene butadiene rubber and super-plasticizer Flocrete PC200 were used at 10% and 1.4% of the cement weight, respectively. The study evaluates key mechanical properties, including flexural, compressive, and tensile strengths, at 28 and 90 days. Seven replacement ratios of brick waste were tested: 0, 10, 20, 30, 40, 50, and 60%. The experimental results showed that the compressive strength achieved its optimum strength at a 30% replacement ratio, while the flexural strength reached it maximum value at a 40% replacement ratio. Additionally, it was observed that brick waste reduces the density of polymer concrete, which could potentially lower the dead load of structures and result in cost-effective construction.
Abstract
The aim of the presented is to investigate the effects of different helical fin pitches (20, 40, and 60 mm) on the performance of helical fins on inner tube outer surface. With an outer tube diameter of 65–75 mm, an inner tube diameter of 25–35 mm, and a length of 400 mm, water was used as the heat exchange fluid. The cold fluid entered the inner tube at a 20 °C temperature, with a Reynolds number ranging from 3,000 to 10,000. The hot fluid flowed through the annular space between the two tubes at a constant rate. The study utilized numerical simulation in ANSYS FLUENT v.21 software. The inner pipe was constructed of aluminum, while the outer pipe was insulated. The numerical results indicated that heat transfer and thermal performance initially increased and then decreased as the pitch of the helical fins increased.
Abstract
The present study uses three mathematical approaches to analyze the dual-purpose solar collector, making it a novel contribution. Three MATLAB codes (C1, C2, and C3), each with its mathematical model, are developed. The effectiveness- number of transfer unit method is used in C1. The heat removal term is used in C2. In C3, the effectiveness term of the parallel flow heat exchanger is used. Mathematical modeling, simulation, and experimental validation are conducted for each code. The calculated numerical-experimental errors revealed excellent convergence. The root mean square error and the mean absolute error for C3 are 1.8 and 1.5, respectively, which are less than for C2 and C3. This indicates that C3 is a reliable approach and can assist researchers in future analysis of the dual-purpose solar collector.
Abstract
Due to the rising demand for battery-operated electrical vehicles (EVs) and equipment, it has become essential to establish a system that is continuously monitoring and managing the performance of each battery. This article presents the design of Battery Management System (BMS) based on intelligent fuzzy logic controller (FLC). The development of battery models and design of FLC is performed within the environment of MATLAB programming software. The FL controller uses the monitored signals of the battery, represented by state of charge (SOC), state of health (SOH) and temperature (Temp) as the input variables, which are processed within fuzzification and defuzzification stages inside the FL platform to yield crisp outputs. The effectiveness of proposed controller has been assessed under two types of member functions (MFs): triangular MF and Gaussian MF. As compared to other existing control techniques in the literature, the proposed FLC outperforms these control schemes in terms of charging time. Moreover, the numerical results showed that FLC based on Gaussian MF gives better performance as compared to that based on triangular MF in terms of accuracy and charging time.
Abstract
This paper explores the impact of participatory design in educational spaces through a case study of the Law Faculty Library at the University of Prishtina. Within the course of Interior Design at the Faculty of Architecture a participatory project was initiated, engaging students, faculty, and staff in a collaborative process to address poor functionality and out-dated infrastructure and to develop a contemporary design that introduces flexible zones, modular furniture, and modern lighting, creating a dynamic, user-centered setting. The study emphasizes the value of participatory design in interior design education in improving the student learning experience and producing adaptable, functional interiors aligned with user needs.
Abstract
This research dealing with mathematical modeling of sewer network in urbanized area, which means creating a mathematical model in mathematical software MIKE URBAN. This software is designed to compute and create the model of surface runoff in chosen area. This model is creating because sewer system in Slovakia and also in the world is out-dated. Out-dated means, in the past sewer systems were designed for the fastest transport waste water and rain water from urbanized area. The rapid development of cities in the form of increasing urbanization has changed the original hydrological processes in cities. An increase in surface runoff with an out-dated sewage system can result in local floods in a short period of time. Therefore, it is necessary to create mathematical models to assess sewers in terms of their hydraulic capacity.
Abstract
Fuel cells are a pivotal technology in the changes towards sustainable and clean energy methods due to their high energy performance and environmentally aligning functioning. This investigation carried out an overall computational analysis to investigate the influences of these crucial factors on the efficiency of a single fuel cell. This research work measures the influence of parameters on key performance variables like polarization curves, electric potential and current density output. The results show that higher inlet pressures and mass flow rates significantly enhance reactant transport, thereby decreasing concentration losses and improving polarized current outcomes. GDL porosity and electrode exchange coefficients are found to play a significant role in enhancing reactant distribution and electrochemical reaction kinetics leading to good utilization of fuel and higher cell performance. Conversely, higher inlet temperatures negatively impact efficiency due to rises in thermal stresses and reduced reactant concentrations at critical reaction zone. Furthermore, the research identifies optimal ranges for these parameters, offering actionable insights for improving fuel cell design and operation. These results contribute to the broader efforts in advancing fuel cell technologies paving the way for their effective deployment in clean energy applications. This study underscores the importance of integrating computational analysis into the optimization of high-performance and durable fuel cells for the energy demands of the future.
Abstract
This paper presents experimental results using the ultrasonic flow-meter “Dnipro-7U” on limited straight sections of water pipelines located before turns and branches. In these pipeline sections, asymmetric water velocity profiles can lead to reduced accuracy in flow measurements using an ultrasonic flow-meter.
It was observed that the accuracy of the ultrasonic flow-meter on short straight sections depends on both their length and the water flow regime. The device's passport error is specified as 2%. An additional error (ranging from 0 to 3%) may arise due to variations in the reliability of water flow and supply characteristics input by the operator, deviating from the average values used in the operational calculation algorithm during measurements.
Abstract
Plastics are low cost, lightweight, and many uses material. As result, increase in plastic led to the environmental pollution. So, this incited the researchers to use the plastic in concrete to produce sustainable concrete. In this paper, experimental work was presented to investigate the behavior of columns with and without waste fibers polyethylene terephthalate under axial load. These columns were divided into three groups depended on ratio of fiber 0%, 0.5%, and 1% and configuration of steel bars. Some mechanical properties of concrete were tested. Main results obtained fiber inclusion resulted in an improvement in splitting and a decrease in compressive strength. Results also showed an improvement in crack load for columns when adding fiber, which reached the highest percentage about 45.79%.
Direction Dependent Mechanical Behavior of ETFE Foils
Az ETFE fóliák irányfüggő mechanikai viselkedése
In recent decades, the use of ethylene-tetrafluoroethylene (ETFE) membranes has been increasing in the building industry for lightweight transparent structures. The nonlinear behavior of this material has garnered significant attention from researchers in recent years. However, there remains uncertainty regarding whether the material is orthotropic or isotropic, leading to conflicting conclusions in the literature. This work aims to clarify this question.
To achieve this, uniaxial tensile tests were conducted on NOWOFLON ET 6235 foil at temperatures ranging from 16 °C to 32 °C, covering material orientations from –90° to 90° relative to the machine direction in increments of 15°. The results indicate that there is no significant difference in behavior based on cut orientation at small strains. However, a slight orthotropic behavior becomes evident after the initial inflection point on the engineering stress-strain curve, as confirmed by ANOVA analysis.
A kupolák tisztelete
Az egykupolás dzsámik eredete és térhódítása az oszmán építészetben I.
Respect for Domes
The Origin and Spread of the Single-Domed Mosques in the Ottoman Architecture I.
Az oszmán építészet a turisták számára egyet jelent a Kék mecsettel, a szakemberek többsége számára pedig a bizánci építészet, különösen pedig a Hagia Sophia másolásával. Igaz, Bizánc és Konstantinápoly, amely akkor szinte egyet jelentett a művelt világgal, vonzotta és inspirálta is a szomszédságában államot alapító oszmánokat. De volt ezzel így más is, akár tanulmányunk tekintetében szűkebb értelemben a kupolák esetében is. A Földközi-tenger keleti medencéje és a mai Közel-Kelet évezredes hagyományokkal bír a boltozatok és kupolák alkalmazása terén. Különösen igaz ez Iránra, ahol az egyéb építőanyagok híján rákényszerültek ezekneknek a szerkezeteknek az alkalmazására és továbbfejlesztésére is. Ez a Szeldzsuk Birodalomban olvadt össze a nomád törökség kupolatisztelő hagyományaival, és ez az ötvözet termékenyítette meg az oszmán építészetet, amelyet természetesen színesített a bizánci, sőt az itáliai reneszánsz építészet is. Az oszmán szakrális építészet legjellegzetesebb produktuma az egykupolás dzsámi, mely szeldzsuk alapokból fejlődött ki, de már a 14. század első harmadától oszmán alkotásnak tekinthető. Akár önálló épületként, akár összetettebb tér uralkodó elemeként alkalmazzák, az egykupolás dzsámi lesz az oszmán legmeghatározóbb építészeti eleme. Ennek kialakulásával és fejlődésével foglalkozik a jelen tanulmány, mely két részletben olvasható. A második részt a következő számunkban közöljük.
Abstract
The wall paintings in Ottoman religious buildings in Albania exhibit a complex blend of cultural, religious, and aesthetic features. This study examines four significant religious buildings in Albania - two mosques and two Tekkes - and analyses the decorations found in these murals, focusing on their typological classification, symbolic meanings, aesthetic character, and contextual relevance. Employing a qualitative research methodology that includes literature review, site observation, architectural documentation, and comparative studies, this research aims to provide a comprehensive understanding of these wall paintings. The findings highlight the aesthetic, religious, and cultural significance of the murals within the broader narrative of Islamic art and architecture. This research enhances the understanding of Albania's particular involvement in the Ottoman artistic inheritance and emphasizes the necessity of preserving these important artworks.
Abstract
Two-layer composite beams using plain concrete reduce structural component costs and improve flexural performance. The research will analyze the flexural behavior of concrete beams reinforced with two kinds of bars. Four specimens used a single layer of conventional and high-strength concrete, whereas the other four employed a two-layer beam integrating both types of concrete. This research included two types of reinforcement: steel and glass. The upper layer used 62 MPa high-strength concrete, while the lower layer comprised 38 MPa regular concrete. Bilayer beams provide a greater ultimate load capacity than one-layer concrete beams. The flexural capacity of high-strength and bilayer steel-bar beams exceeded that of conventional concrete beams by 9.46 and 19.76%, respectively. Bilayer beams support 18.85% more loads than conventional concrete beams.
Abstract
Fire simulations are becoming more and more widely used in fire protection practices. In order to achieve more accurate results, it is inevitable that simulations are always developed. This study investigates the fire behavior of various complex wooden geometries. This research aims to enhance the understanding of fire propagation of different geometries made of wood. The simulations are performed using fire dynamics simulator, which incorporates heat transfer, combustion, and fluid dynamics principles. Key parameters like temperature and heat release rate are analyzed for each of tree geometries. The research contributes to the development of more accurate fire models. It also provides the basis for further development of simulations including more complex geometries.
Abstract
Water is the main source and element of life on Earth for the survival of living organisms; agricultural, economic and social activities. With the development of modern technologies, including geographic information system and remotely sensed data to study natural resources, including water detection. These techniques use to prepare a digital map depending on determine the optimal location. With help of global positioning system receiver, the coordinates of the well sites are determined and fixed on the ground, and then it documented using geographical information system. The result is to specify eight artesian wells distributed on area of interest with area covered 125,000 m2 for each well. This contributed to increasing green areas from 2% to 33% of the total study area and creating a green belt.
Abstract
Rail stations are locations where passengers are picked up and dropped off by trains. This article aimed to determine the optimal locations of tramway stations in Karbala City, Iraq, by using the geographic information systems program. Two model builders had been used, one for origin-destination stations and one for intermediate stop stations. The selection of best locations depended on many criteria, which are the walking distance to active zones were had high trip attraction, land use, and population. For criteria weighting process an analytic hierarchy process method had been used. Five suitable end stations were selected which were located at the entrances of the city, and four groups of intermediate stations had been chosen. Group A consists of 32 stations, group B consists of 26 stations and for group C and D 22 and 22 stations had been chosen. The stations distance was between 300 and 1,000 m.
The Potential Applications of Shape Memory Alloys in Monument Preservation
Az alakemlékező ötvözetek alkalmazási lehetőségei a műemlékvédelmi rekonstrukciókban
Materials with shape memory properties can return to a predetermined shape upon exposure to heat after deformation. This phenomenon was first discovered by Swedish physicist Arne Olander in 1932, when he observed the unusual properties of gold-cadmium alloys. Subsequently, researchers such as Chang and Read also studied this material behaviour as early as 1951. By 1958, these properties were presented at the Brussels World Expo, and in 1961, similar characteristics were identified in nickel-titanium alloys at the U.S. Naval Ordnance Laboratory while investigating other properties of the material.
Despite the fact that the knowledge of these materials and their properties dates back more than 90 years, our understanding of them remains relatively limited, and they continue to be the subject of ongoing research. Shape memory alloys have a wide range of applications, including significant uses in the field of medicine. This study focuses primarily on their structural applications, particularly in the context of historical buildings, including their integration as a protective measure against earthquake damage.
The broader understanding and application of shape memory alloys (SMA) offer significant potential for the restoration of historic or heritage buildings, as well as for preventing further damage to their structural systems. This can be achieved without the need for extensive modifications to the original structure, geometry, or appearance. This is due to the mechanical properties of SMA-containing structures, which allow for minimizing the cross-sectional size, the number of anchorage points, and the extent of invasive interventions. Unlike traditional methods, this enables the use of a less intrusive reinforcement approach to protect buildings effectively.
The aim of this research is to present the properties and behaviour of these materials, existing examples where shape memory alloys have been successfully applied, and explore their potential applications.
Abstract
This study assesses the performance of four nature-inspired optimization algorithms—Dynamic Differential Annealed Optimization (DDAO), Flower Pollination Algorithm (FPA), Firefly Algorithm (FF), and Particle Swarm Optimization (PSO) for achieving optimal space truss design. The aim is to minimize the structural weight of three benchmark trusses (10-bar, 25-bar, and 72-bar) while meeting stress and displacement constraints. The key contribution of this work is the first systematic evaluation of FPA in space truss optimization, demonstrating its greater effectiveness in obtaining optimal or near-optimal solutions with faster convergence and higher stability compared to PSO and FF. The results also highlight the limitations of DDAO in handling constrained engineering problems. Findings confirm that FPA and FF are highly effective for structural optimization, offering robust solutions with minimal computational cost. These insights contribute to advancing metaheuristic-based structural design, supporting the adoption of FPA in large-scale optimization problems.
Analysing Construction and Building Techniques of Neogothic Stellar Vaults
The Case of the Cathedral of Košice
Neogótikus csillagboltozatok szerkesztés- és építéstechnikájának elemzése geometriai vizsgálattal
A kassai dóm példája
In this article, we present a point cloud-based geometric analysis method applied to the 19th-century stellar vaults of the Saint Elisabeth Cathedral of Košice (SK). We based our analysis method on the geometric typology systems we worked out for net vaults during our earlier research. After elaborating on the method’s application to stellar vaults, we present the results of the analysis. This includes the exact geometric description of the vaults’ webbing and rib system, which allowed for deductions about their original construction techniques. Then, we present the re-modelling of the rib systems of the cathedral’s stellar vaults based on the most influential theoretical works of the 19th century (B. Ranisch, F. Hoffstadt, G. G. Ungewitter), such as the principle of the longest route or projecting the junction points to a spherical surface. Afterwards, the comparative analysis of the real vault geometries and the re-modelled rib systems was carried out. Based on this, we discussed the potential reason behind the differences detected. This gives a valuable insight into whether the 19th-century theoretical works and their contemporary building practices differed. Additionally, we elaborated on the implications of the multiple possible three-dimensional geometries of the same rib pattern regarding the authenticity of theoretically reconstructed stellar vault structures.
Abstract
The European Union's (EU) future will be fundamentally determined by innovation-based competitiveness. The study examines what characterized the EU's innovation status as a whole and its member states between 2017 and 2024. For the situation analysis, the study examines the development of the Summary Innovation Index (SII) values describing the innovation status of the member states using the ARIMA model and K-means clustering. The study estimates the expected innovation status of the EU and its member states in the medium term using the Linear Trend Model. The results show that innovation is the least coordinated area of the EU cohesion policy, as there is a significant gap in the innovation status of the member states. In the case of the two extreme innovation values, the difference is four times greater. By this ratio, the average innovation development of the Scandinavian states is higher than the development level of some Eastern European member states. The extrapolation results show that the innovation gap will likely persist in the medium term despite continuous modernization.
Abstract
Car body panels are one of the vehicle components that support the existence of the car interior and maintain the safety of passengers, especially in monocoque-type car bodies. Car panel materials, which generally use steel materials, have the disadvantage of being relatively heavy and having a short service life due to corrosion. To achieve higher energy efficiency in energy-efficient vehicles, honeycomb sandwich structures made of polymer composites, which are lighter in weight, can achieve a higher power-to-weight ratio. In this research, a polymer matrix composite material with a honeycomb sandwich structure was created and tested as an alternative material to replace steel for car body panels. Composite made from WR-200 Fiberglass as a reinforcing agent and SHCP 2668 CM-M resin as a bonding agent to determine the effect of the detailed honeycomb sizing, especially on the flexural strength and stiffness characteristics, have been used. Several specimens were made with variations in cell-pitch sizes of 20 and 40 mm, variations in the cell-height size of 10, 20 and 40 mm and variations in the thickness of the cell wall thickness obtained from the use of layers of Fiberglass of one, two and four layers. From the bending tests performed on all specimens, it was known that the highest flexural strength value have the specimens with a cell-pitch size of 20 mm, cell height of 10 mm and cell wall thickness of 4 layers of Fiberglass, namely 36.13 N mm−2. The specimen has the highest stiffness value with a cell pitch of 40 mm, cell height of 40 mm and cell wall thickness of 4 layers of Fiberglass, which is 338 N mm−1.
Abstract
Applying Machine Learning (ML) has seen rapid progress in many disciplines, such as architectural design. Recent research reveals promising potential for integrating ML in solving design problems. This paper explored how ML can serve as a tool to guide designing action. It conducted thematic analyses of ML experiments in the architecture domain to build a framework addressing two key aspects: the tasks achieved and the required training dataset. The paper found that ML mainly performs design generation, optimization, and recognition via classification and clustering. Three scenarios of design generation using ML have started from pre-design requirements and constraints, conceptual design, or parametric design. ML can predict design features based on prescribed performance or calculate performance metrics, based on varied design options. Design recognition classifies or clusters designs to detect their styles, typologies, and morphologies, besides tracking the process of best practices. The specifications of training datasets vary in terms of data sources as real or virtual, techniques for representing datasets as visual or textual, and the relationships between input and output datasets as refinement, embodiment, sorting, or evaluation. The findings revealed that ML has a wide range of experimentation and opens more opportunities for further integration in the design process.
Abstract
Systems based on mobile multirobots have gained considerable attention in the past two decades because of their efficacy and flexibility in various real-world applications. An essential component of these systems is multi-robot task allocation (MRTA), which concerns allocating tasks to mobile robots in an efficient manner. The effectiveness of MRTA is influenced by the size of the search space and computational time, and both increase substantially as the number of tasks and robots involved increases. This study introduces an effective solution to the MRTA problem by employing a two-stage approach. First, nearby tasks are automatically grouped into clusters by using an enhanced dynamic distributed particle swarm optimization algorithm. Second, mobile robots are assigned to the closest clusters. To demonstrate the effectiveness of this approach. Simulations are conducted to compare the proposed method with particle swarm optimization and differential evolution approaches. Numerical results confirm that the proposed approach exhibits highly competitive performance in terms of clustering cost, clustering time, and overall time (clustering and assigning time). This approach is advantageous for real-world applications involving numerous robots and targets.
The Operation of the Local Sections of the Hungarian Association of Engineers and Architects Between the Two World Wars Through the Example of the Pécs Section
A Magyar Mérnök- és Építész-Egylet vidéki osztályainak működése a két világháború között a pécsi osztály példáján keresztül
The aim of the Hungarian Association of Engineers and Architects as a professional and interest association, which had been in operation since 1867, was to promote mutual acquaintance, exchange of ideas, discussion of conventions and professional issues, the creation of a library, the publication of journals and books, and the establishment of a provident fund. From the beginning of the 20th century, the Association sought to concentrate technical professionals from the countryside into local sections, hence preventing the establishment of independent countryside associations. During the Dual Monarchy (1867–1918), 16 sections in the countryside were set up, and 4 more between the two world wars. The one in Pécs had been operating since 1930. The study describes the functioning of local sections, their relationship with the parent association and analyses their membership. It traces the history of the Pécs Section from its establishment to its liquidation in 1946, covering the changes in the composition of membership, the tasks and work of the officers, and the activities of this section as well as its relation to the Association. Among such activities, historical sources, recorded lectures, debates, field trips, social dinners, soirees, and exhibitions. Most of the members of the Pécs Section were engineers, as in the parent association, who worked in various technical offices in the city, such as the Hungarian Railways (MÁV) offices and in the coal mines of the Danube Steamship Company (DGT). However, the architects were also very active in the life of the Pécs Section, organising lectures, debates and exhibitions. The most significant local event of the period between the two world wars was the association’s 1936 travelling assembly held in Pécs, and the 1941 field trip. Despite the late establishment of the Pécs Section it was the largest and one of the most active local sections of the Hungarian Association of Engineers and Architects.
Abstract
This paper examines a civil law legal institution, contractual freedom, from an economic perspective in connection with economic freedom. The paper investigates the following cases, as the economic freedom of a given national economy is measured in four main areas: the size of government, legal system and property rights, sound money, freedom to trade internationally and regulation of credit, labour markets and business life. In the Economic Freedom of the World 2022 Annual Report, Hungary ranked 55th in the global ranking with an overall score of 7.12, compared to 44th in 2000, with a score of 7.03. Neither the change in score nor the ranking is significant. However, the fact that the country has fallen further behind in this international ranking is not encouraging.
Abstract
The power can be taken from the ICE crankshaft is a function of the continuously changing adhesion coefficient between the tire and the road surface and the normal force of the wheel. In order to maximize vehicle dynamic performance, Torsen differentials were developed change the power transmission ratio between the wheels or axles depending on the tractive force can be transmitted. The Torsen T-2 differential having internal kinematic ratio i = −1, can be used both as a front and rear as well as a central differential. The torque ratio between the axles connected via Torsen T-2 differential is ensured by the high internal mechanical friction, can be derived from the axial tooth force component of the helical gear drive applied.
The aim of this study is to create a general mathematical model of the Torsen T-2 standard construction. Using this model enables to perform a detailed kinematic analysis of the operation of the entire mechanism. This model will be created by the motion of the gears since coordinate systems are ordered to each moving gears. Based on the Connection I statement the conjugated gear profiles of the gear pairs can be determined by mathematical and computational ways. After that, the CAD models of the gears can be created using 3D software for further finite element analysis. These CAD models are also required for computer-aided manufacturing (CAM) and CNC programming. We prove the usefulness of the model in the case of creating a concrete geometric facility produced by 3D printing.
A budapesti államszocialista kislakótelepek környezetének vizsgálata a 15 perces városmodell elvein keresztül
Examination of the State Socialist Housing Estates’ Environment in Budapest Through the Principles of the 15-Minute City Model
Az elmúlt évek városépítészeti hívószava a 15 perces város volt, melynek célja az újépítésű városrészek és a kortárs városrehabilitációk számára egy urbanisztikai keretrendszert, útmutatót nyújtani. Nemzetközi és hazai kutatások is vizsgálták már a kortárs lakóparkokat és az államszocialista nagylakótelepeket ezen keretrendszer alapján. Pont ezért a kutatás alaphalmaza a kislakótelepek lettek, melyek egyfelől a nagylakótelepekkel szemben / ellen / helyett valósultak meg, másfelől pedig a kapitalista lakóparkok előképeként szolgáltak az államszocialista időkből. Ezen kettőség mellett az 1945–1990 között épült budapesti kislakótelepek téri viszonyai egy eddig feldolgozatlan téma. Ám a több mint 100 db esettanulmánynak köszönhetően ez a vizsgálat lehetőséget teremt ezen lakhatási forma részletesebb megismerésére, és a 15 perces városmodell módszertanának kipróbálására, fejlesztésére. Vajon a kislakótelepek megfelelnek-e a 15 perces város keretrendszerének? Vagy a kislakótelepek környezete beleolvad Budapest nagy rendszerébe, s a városban betöltött lokáció (zóna) az, mely meghatározza a közvetlen szomszédság karakterét? Ezen kérdések megválaszolásához a 15 perces városmodell városépítészetileg releváns három elvén – közelség, sűrűség, diver-zitás – keresztül vizsgáltam Budapest összes 1945–1990 között épült kislakótelepének 15 perc sétálással elérhető környezetét hivatalos térképek segítségével. A kutatásban használt adatok leginkább az épített környezet leírására szűkülnek (pl. lakásszám, szintterületi mutató, beépítési mód), ám a tágabb kontextus (pl. lakosságszám, vásárlóerő) megjelenítése is realizálódik.
Abstract
The prosthetic feet available in the market are characterized by high costs and are made of carbon fiber materials, fiberglass, or silicone-coated wood. This study aims to design and manufacture a prosthetic foot to enhance biomechanical performance and user comfort and mimic the natural movement of the human foot; the foot will be designed and manufactured from low-cost materials, namely carbon fiber filaments, using 3D printer technology. The practical part consists of tensile, fatigue tests, and manufacturing the foot using a 3D printer. In this study, the ANSYS program will also analyze the designed model numerically to determine the stresses generated when applying the assumed body weight to the foot model. The results showed that the model is successful in terms of design and does not suffer any mechanical failure during use, in addition to the success of the selection of the material used in the manufacturing process due to its mechanical properties, where the yield stress value = 36.4 MPa, the ultimate stress value = 58.39 Mpa and Young's modulus = 1.23 GPa.
Abstract
The purpose of this work is to establish the relationship between surface roughness and erosion processes of Ba35brass pipes subjected to abrasive particles. Brass samples were prepared with different levels of surface roughness, obtained by polishing using abrasive papers of various grain sizes: P80, P120, and P320. These samples were eroded using a recirculating erosion test bench. To analyze the erosion kinetics, the surface roughness values (Ra and Rz) as well as the cumulative mass loss were measured at specified time intervals. In parallel, mathematical models were developed to simulate the evolution of surface roughness and cumulative mass loss, based on optimization methods. The results show that rougher surfaces, such as those prepared with P80 grit paper, record a higher erosion rate, reaching 0.47 mg/h, compared to smoother surfaces, such as those obtained with P320 paper, whose rate is 0.19 mg/h. The developed mathematical models indicate that the surface roughness follows an exponential decrease, while the cumulative mass loss shows a logarithmic growth. Furthermore, a linear correlation was highlighted between the erosion rate and the surface roughness. This study highlights the crucial importance of surface roughness in erosion processes and provides guidelines for optimizing the design and maintenance of cast iron pipes.
Abstract
This paper emphasizes the role of fuel substitution in mitigating vibrations and enhancing the performance and reliability of internal combustion engines (ICEs). Using MATLAB for modal analysis, the study investigates natural frequencies and identifies potential resonance issues within critical engine components. The primary focus is on analyzing a four-stroke single-cylinder engine under various speeds and measuring the effects of fuel type on engine performance and efficiency. A comparative assessment evaluated vibration levels between natural gas and petrol by measuring engine vibrations across a range of speeds and analyzing the impact of varying dimensions of internal moving components on performance parameters. Results indicate minimal differences between the engines at lower speeds (1,500–2,000 rpm), while significant increases in vibrations were observed at higher speeds (2,500–3,000 rpm) for the gas engine, highlighting potential mechanical instability. At higher speeds, vibrations peak at the top of the engine, reaching 200 m s−2 with petrol and 240 m s−2 with natural gas. The experimental setup, including accelerometer modules and control systems, enabled real-time vibration monitoring. Numerical results showed that the longest connecting rod (197 mm) yielded the highest displacement, velocity, and acceleration metrics. These findings underscore the advantages of using natural gas as a fuel, including its availability, cost-effectiveness, and environmentally friendly nature, as it produces significantly lower harmful emissions compared to petrol. Additionally, the study offers insights into vibration-damping mechanisms and the influence of modifications to internal moving parts, such as crankshaft diameter and connecting rod length, on engine performance and stability.
Abstract
Recent advances have enabled solid waste byproducts to effective soil amendment in order to minimize the use of inorganic fertilizers and increase crop yields to provide food for a high-population world. This review aims to summarize the essential nutrients required for crop production, the ability of nutrient supply of solid waste byproducts as soil conditioners, and its impacts on plant growth and soil properties. This paper analyzes the sources of plant nutrients, functions, symptoms of deficiency, and corrective measures. This review analyzed the byproducts of municipal solid waste compost, waste biomass, biochar, farmyard manure, press-mud molasses, vinasses, olive mill waste, spent mushroom compost and fly ash (FA), cow dung vermicomposting with FA, FA mixed with biochar, sewage sludge-FA mixture, fiber sludge, sewage sludge, bauxite residue, poultry waste to determine their ability to supply nutrients, affecting plant growth and soil properties significantly. This review also discusses the challenges associated with solid waste byproducts used in agricultural soil amendment on the environment and human health and possible future strategies to be adopted. Overall, this review provides insights to farmers about the use of solid waste byproducts as soil conditioners for the enrichment of essential nutrients and soil properties in farming soil.
Abstract
This study investigates the utilization of biochar (WHBC) from water hyacinth biomass (WHBM) for sustainable soil amendment to improve soil quality. WHBM and WHBC are prepared and characterized with thermogravimetric analysis (TGA). For that, physiochemical, proximate, ultimate, and elemental analyses are done and characterized by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDAX) to identify the suitability of soil amendment. WH biomass is carbonized with a limited air supply in a muffle furnace, and the study found that 300–664 °C temperature is the optimum condition for producing biochar from TGA. XRD of WHBC displayed more crystallinity than WHBM. FTIR of WHBC showed higher carbon stability increment than WHBM. The SEM micrograph of WHBM showed that compact, and fibril structures and WHBC revealed macroscopic changes that can significantly improve the soil properties. EDAX analysis of WHBM and WHBC proved that various soil nutrients can be helpful for plant growth. The study shows that WHBM can be utilized as a soil quality amendment material by converting it to biochar and an effective material for carbon storage in soils.
Abstract
This study uses numerical modeling to explore the intricate relationship between low-velocity impact and composite materials. The study investigates the impact response of composite materials under low-speed loading circumstances in great detail. Two specimens were prepared for the current study the first one has a uniform thickness for each layer, and the second is prepared with altering layer thicknesses. A tensile test was employed to obtain the mechanical properties to use it in the numerical analysis. An impact test was employed in this analysis, where the impactor was modeled also on a height of 300 mm, the analysis time was taken as 0.08 s to capture all the impact. The numerical analysis was verified with other studies, and the error percentage did not exceed 2%. The results showed that the second specimen with alternating thickness had the best behavior.
