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

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Abstract

This work investigates the effect of two wall roughness types, triangular and circular, on convection and radiation heat transfer in a small space. The ANSYS Fluent is used to do thermal and dynamic modeling; the left wall is warmer than the right one. The upper and lower walls are adiabatic. The Nusselt numbers are compared in all cases and for two Rayleigh values, which change based on the cavity's characteristic length. The results show temperature contours and Nusselt curves. It was observed that the roughness had a strong effect on the air's thermal behavior inside the cavity, where the Nusselt decreased in both roughness cases, especially at small heights. However, the largest decrease is in the triangular case and for angles less than 90°. For 72°, Nusselt is 13.32 and 6% less than smooth and circular cases respectively.

Open access
Pollack Periodica
Authors:
Salman Khayoon Aldriasawi
,
Abbas Nasser Hasein
,
Ashham Muhammed Anead
, and
Barhm Mohamad

Abstract

The study analyzed surface treatment's impact on mechanical properties of Fe-based amorphous coatings. Specimens underwent six-hour treatments at 670 and 770 °C using vacuum heat. Results revealed distinct mechanical features in the coating: Vickers hardness reached 755, scanning electron microscope images displayed glassy phases, showcasing good wear resistance and compressive residual stresses at around −55 MPa. A remarkable 122% increase in compressive residual stress was noted through combined vacuum heat treatment and sandblasting. Volume wear decreased from the initial 18 to 14 mm3 after treatment at 670 °C followed by sandblasting, indicating a 30% enhancement in wear resistance. Yet, using vacuum heat treatment at 770 °C negatively impacted the coating's properties.

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Abstract

The paper presents a normalized, varying step size-based least mean square-based control for a standalone microgrid and Ant Lion optimization-based maximum power point tracking. This modified version of the incremental conductance algorithm addresses issues like slow dynamic response, fixed step size issues, and steady state oscillations. Comparative analysis with well-known techniques shows that Ant Lion optimizes the tracking of maximum power points more accurately, with fewer oscillations and increased efficiency. Power management and power quality are maintained through proposed adaptive voltage source converter control. The proposed voltage control shows better performance under various dynamic and steady conditions.

Restricted access
Pollack Periodica
Authors:
Mahdi J. Hussein
,
Maryam H. Naser
,
Fatimah H. Naser
,
Ali Hameed Naser Almamoori
, and
Mohammed L. Hussien

Abstract

The present research studies the effect of adding sugar factory waste sugarcane molasses as an alternative to chemical inhibitory additives manufactured on concrete cast during hot weather in the summer of Iraq. The current study includes a study of the setting time for cement paste and workability for fresh concrete and some mechanical properties of hardened concrete with sugarcane molasses using percentage 0–0.3% of cement weight. The study also included studying the value of pH of concrete to investigate the effect of sugarcane molasses on reinforced concrete. The results showed that the sugarcane molasses can be used by about 0.1% of cement weight for medium projects and between 0.1 and 0.2% for large projects. It was also found that the compression strength increased by about 11.5% and the indirect tensile strength increased by about 7.5 and 7.4% for splitting and flexural test, respectively for concrete mixtures containing 0.2% of sugarcane molasses.

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Abstract

Helical concrete columns are a new type of structural members which arose in new twisted buildings to satisfy architectural purposes. Helical concrete columns have a unique geometry which depends on the values of twist angle (ϕ) and the tilt distance of the center of rotation. According to the ACI T1.1R-01:2001 guidelines, a combined effect of axial load and lateral cyclic displacement protocol was applied to twelve specimens. Nonlinear finite element method was used to conduct the analysis and the numerical simulation for the helical reinforced concrete columns. The findings of the study revealed that the value of the buckling load, lateral displacement and the drift angle of helical concrete columns are significantly affected by the tilting distance of the rotation center and the twist angle.

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Pollack Periodica
Authors:
Anna Liová
,
Roman Výleta
,
Kamila Hlavčová
,
Silvia Kohnová
,
Tomáš Bacigál
,
Jana Poórová
, and
Ján Szolgay

Abstract

Design flood hydrographs are often used to project safe and cost-effective hydraulic structures. This study proposes a system based on a combination of empirical and statistical approaches for constructing synthetic design flood hydrographs, that practitioners can easily apply. The system uses scaled observed seasonal flood hydrographs and respects the dependence structure among the flood peaks, volumes, and durations deduced from the set of seasonal flood hydrographs observed. The method was developed and tested based on data from the Horné Orešany reservoir in Slovakia.

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Abstract

In the post-pandemic period, cities are committed to creating healthier and more healing urban environments. In high-density urban environments, urban complexes are increasingly assuming the function of enriching the external space and activating the vitality of cities, and their architecturally oriented public spaces have great potential for the promotion of residents' health. However, current research on public space and health has focused on green spaces and neighborhoods, and has not yet systematically sorted out the pathways that influence how building-oriented public space can contribute to health. In order to fill the gap, this study attempt to establish a model of health-promoting architecturally oriented public space, which can provide a reference for the similar projects.

Open access
Pollack Periodica
Authors:
Mohammad Kherais
,
Anikó Csébfalvi
,
Adél Len
,
Attila Fülöp
, and
Judit Pál-Schreiner

Abstract

In the last two decades, the utilization of timber in construction has gained increasing attention among researchers and sustainable building designers. Therefore, studies of climate impact on timber structures have been conducted, many of them focusing on the moisture content caused changes in timber. In the present study, four-point bending tests have been performed on three testing groups, containing 30 samples each. The first group has been tested under its natural conditions, while the second and the third groups were fully saturated with water. The third group was glazed with a protection material. The results show the changes in the modulus of elasticity and the modulus of rupture caused by the moisture content increase. In the same time the material behavior changed from brittle to semi-ductile or ductile for some samples.

Open access

Abstract

This paper is dedicated to the memory of Dr. Miklós Iványi, who instilled in the authors an appreciation for experimental investigations, which are foundational to understanding material and structural behavior. Timber-concrete composite structures are increasingly adopted for new buildings due to their favorable sustainability parameters and the increased availability of cross laminated timber. For larger spans, however, solid timber floors lead to higher timber volumes and the use of glulam beams may become necessary for a more efficient use of wood. This paper presents laboratory tests of glulam-concrete composite beams and is the first in a series of two papers on investigating the associated failure mechanisms. Three full-scale glulam-concrete beam specimens were studied. The glulam and concrete are monolithically interconnected using a continuous layer of adhesive. Shear reinforcement was added to the glulam beams to allow for failure mode control. Static load tests to failure were conducted along with acoustic emission monitoring to track the progression of the failure. The results indicate that the shear reinforcement of the glulam layer affects the load capacity of the composite beam through shifting the failure from a shear to a tension failure mode. Similar glulam-concrete beams can enable larger span applications for buildings and bridges while maintaining an attractive sustainability performance.

Open access

Abstract

Cement and concrete are the most crucial and dominating engineering materials in the construction sector. Cement serves as an excellent binder for concrete and when it is treated under unusual conditions either to satisfy accelerating or retarding requirements by the construction industries, admixtures role comes into the effect. The construction industry has been searching for retarding admixtures and the optimal dosage level, particularly for ready mix concrete applications. Generally the retarding admixtures such as organic retarders (lignosulphonates, hydroxycarboxylic acids and their salts, phosphonates, sugars) or inorganic retarders (phosphonates, borates) were generally used to reduce the speed of the reaction between cement and water by altering the growth of the hydration products and/or limiting the rate of water penetration to the cement particles. The research was still in its infancy stage in terms of determining not just the appropriate dosage amount, but also the ideal retarder materials for the aforementioned uses. In considering this industrial need, an attempt was made on utilizing the usage of sugar in the concrete to study the retarding effect without affecting the strength properties of cement. The sugars usage levels were at 5, 10, 15, and 20% of the usage of cement to investigate consistency, setting time, compressive strength and micro structure properties at the curing age of 7, 14 and 28 days on the mortar specimens. The conclusions of the study reported that setting time was extended with increase of the dosage levels of sugar. However in considering the strength property, less than 5% of sugar dosage level can be better for the application as retarding agent in the industry applications.

Open access

Abstract

This paper presents an investigation on a battery-less voltage of Piezoelectric (PZT) V-shape cantilever beam Energy Harvester (EH) using human body vibration. The frequency ranges are walking (0–5 Hz), running (6–10 Hz) and motions (11–15 Hz) for human movement. Pacemaker devices typically require a lower resonant frequency with higher voltage which is powered by batteries. The battery has a limited duration during its working process and the battery is difficult to replace in the human body. To address the aforementioned issue, a V-shape cantilever beam EH has been developed as a solution to overcome these limitations. The cantilever beam was designed in COMSOL Multiphysics software 5.5 version using the Finite Element Analysis (FEA) method for experimental investigations followed by three categories of frequency ranges of the human body. The simulation results showed that the generated battery-less higher voltage was 269 mV (AC) at the resonant frequency of 14.37 Hz in the motion range of 11–15 Hz. Later, an Ultra Low Power (ULP) electronic circuits will be designed and simulated in the LTSPICE software to convert and boost-up from 269 mV (AC) to DC voltage attained. The estimated output power of the energy harvester system can be powered up (4.7 µW) for modern pacemaker applications.

Open access

Abstract

Aim

The occlusion of the teeth is affected due to the appearance of micro-cracks resulting from maximum stresses in the contact zones between the wire and the bracket under normal and tangential loading. The objective of this study is to evaluate the surface and volume constraints in the presence of bonding and partial sliding zones on the contact surface between wires and supports. Knowledge of these stress fields will make it possible to better limit the surfaces where most of the micro-cracks occur. Indeed, the evaluation of the stress will facilitate the modelling or application of established micro crack models on this subject, because the initiation of micro-cracks often appears on the contact surface or just below it.

Materials and methods

In this study, the two most common situations of contact between the wire and the bracket were studied; the first corresponds to the situation where the wire is positioned in the center of the support (classic friction), and the second corresponds to the situation where the inclined wire touches the ends of the supports (critical contact angle).The MATHCAD software was used to simulate the damage zones for normal loading in the two cases studied (classic friction, critical contact angle). We proposed a Hertzian loading for the first case and a linear loading for the second case. Also, the effect of the additional load during wire tightening applied by the orthodontist was studied.

Results

The charge concentration is located above the contact zone, of the order of 0.3P0 (pressure per unit of arbitrary normal length), according to Mathcad simulation results. The adhesion zone/micro-slip zone contact generates the largest tangential load, which is directed towards the side experiencing the most stress. We also observed that the stick area shifts towards the recessed side when the additional load is applied. Additionally, comparing the configurations, the critical contact angle resulted in a higher maximum shear stress.

Open access

Abstract

The dog clutch offers advantages in mass and efficiency, but faces challenges in mismatch speed synchronization, which affects its shiftability. Face impact between dog teeth also reduces its lifespan. Our previous work introduced the kinematical shiftability condition that ensures impact-free gearshift but had limitations due to analysis assumptions. This study eliminates those assumptions, but uses a similar approach. Based on our previous work for dog clutch engagement dynamics, we develop the dynamical shiftability condition. Validation with full dog clutch dynamics showed an agreement. Employing another previous work that introduced shiftability map and parametric study method, we study system parameters impact on shiftability but based on the dynamical shiftability condition.

Open access

Abstract

The Jordan Museum is the most important modern archeological museum in Jordan. This paper assesses the quality of design and the visitors' satisfaction with the Jordan Museum. Also, it investigates which of the selected performance elements contribute most to visitors' satisfaction. Investigative Post-Occupancy Evaluation (POE) was used within a mixed methodology approach. A questionnaire was used for the quantitative part, complemented by other qualitative methods. Descriptive statistics were used to determine the design quality and visitors' satisfaction. Stepwise regression was used to detect which performance elements predict overall visitors' satisfaction. The design quality of the museum was rated as good, and its permanent galleries were exceptionally rated as excellent. The visitors were generally satisfied with the museum. Visitors were satisfied with the interior and exterior finish but were not impressed with the heavy use of stone in the façade. The simplicity of the museum layout made navigation easy, and visitors were satisfied with wayfinding. This paper is the first to use POE to assess the Jordan Museum. The findings can be used to enhance the management and operation of the Jordan Museum. Also, important performance elements can be developed into guidelines to guarantee effective museum designs in the future.

Open access

Abstract

This study explores the impact of corrosion on Ground Penetrating Radar (GPR) responses through practical experiments and numerical modelling, focusing on rebar diameter reduction, corrosion product layer thickness, crack formation and corrosion product filling in vertical and transverse crack. Practical experiments involved GPR testing of reinforced concrete slab. By analyzing B-scans we identify areas with moderate and severe corrosion. Numerical modelling using the Finite Difference Time Domain (FDTD) Method to model GPR signal propagation in a concrete bridge deck with corrosion is applied. Key finding includes a significant 26.70% increase in reflected wave amplitude when corrosion product filling in vertical crack increased by 400%, highlighting its extensive effect on signal GPR propagation. Reduced rebar diameter led to a 9.79% amplitude decrease and a 0.06 ns arrival time delay. Increased corrosion product layer thickness primarily affected arrival time with a 0.06 ns extension but significantly amplified GPR signal amplitude. These findings offer insights for improving GPR based corrosion detection and assessment methods, leading to more robust systems for concrete bridge deck inspection and maintenance. This paper contributes to understanding how corrosion affects the signal that is detected by GPR. This information can be used to improve the way that we manage and assess corrosion in concrete bridge deck.

Open access

Abstract

Direct current (DC) motors have superior features such as operating at different speeds, being affordable and easily controllable. Therefore, DC motors have many uses, such as machine tools and robotic systems in many factories up to the textile industry. The PID controller is one of the most common methods used to control DC motors. PID is a feedback controller with the terms Proportional, Integral, and Derivative. The proper selection of P, I, and D parameters is critical for achieving the desired control in the PID controller. In this study, the transfer function of a DC motor is first obtained, and the speed of the DC motor is controlled by the PID controller using this transfer function. Then, Particle Swarm Optimization (PSO), an optimization method based on swarm intelligence, is used to adjust the P, I, and D parameters. By using the obtained P, I, and D coefficients, the speed of the DC motor is tried to be controlled, and the effect of the filter coefficient on the system output is examined. The performance of the proposed PSO-PID controller with successful results is given in tables and graphics. Control and optimization studies are carried out with MATLAB Simulink.

Open access

Abstract

Green wall systems have been introduced all over the world as a sustainable solution to combat the hot environment inside buildings and provide thermal comfort by improving the thermal efficiency of the buildings. This study aims to find out whether green walls can be used to manage the inside thermal conditions of Aqaba buildings. It is intended to lessen the impact of Aqaba's harsh warm climate on internal building spaces and achieve a thermal comfort level. A physical live experiment was used to detect the thermal impact of green walls on internal spaces. The thermal performances of two identical real-scale test rooms, one of which had a fixed green facade, were compared. This study concludes that green facades have a significant potential to promote buildings' thermal behaviour in the hot summer of Aqaba and thermally similar regions.

Restricted access

Abstract

The compressive behavior of self-consolidating concrete columns strengthened by hybrid confinement of polypropylene fiber rope and glass fiber-reinforced polymer sheet was investigated experimentally. We cast and tested eight column specimens under axial compression load. (Six confined SCC columns and two conventional SCC columns.) The concrete grade utilized is SCC M40. For reinforcement, the SCC columns are enclosed with GFRP wrap and polypropylene fiber rope in various volumetric ratios. The compressive resistance of a confined SCC column, strength enhancement, stress-strain relationship, ductility ratio, and load deflection relationship are the parameters studied. The results are compared to establish the adequacy of the confinement. The wrapping of GFRP increases the load-carrying capacity and modulus of elasticity.

Open access

Abstract

Whenever a new material is replaced in concrete, some other tests other than strength and durability need to be carried out to validate the viability of the material replaced. This study aims to investigate the sustaining capacity of the light weight concrete manufactured with compost and Ground Granulated Blast Furnace Slag (GGBS) for M sand and cement respectively subjected to high temperature. Four concrete samples are tested, which includes the control specimen and three specimens are opted based on the optimum mix arrived from the strength and durability studies. Thermogravimetric Analysis (TGA) is done on the samples and they are heated up to 1,000 °C. For the specimens tested, the loss in mass with respect to the temperature is obtained. It is noted that the mass loss of the concrete samples with 15% GGBS along with compost at 0 & 10% is found lower than the control specimen. Also, from the loss in mass, the loss of chemically bound water and free CH content can be found, which aids in contributing strength to the concrete. For the concrete to be sustainable, compost can be replaced at 10% and GGBS at 15%.

Open access

Abstract

This paper aims to investigate the effect of liquid heterogeneity on sloshing in a two-dimensional rectangular tank. The container is excited horizontally, and the density of the liquid at equilibrium can almost be considered a linear dependence of the depth. The linearized equations representing the sloshing phenomenon are solved numerically using ANSYS 2020 R2 software and analytically using the separation method of variables in conjunction with the Fourier analysis. On the other hand, a comparison study has been carried out between the obtained results and other works related to the same phenomenon. Overall, the results exhibit considerable effects of variation in the Heterogeneity Coefficient β on the free surface's motion and the pressure distribution within the liquid. Furthermore, the free surface of liquid heterogeneity is also affected by the variation of Excitation Frequency Ω and the Filling Rate h of the liquid in the tank.

Open access

Abstract

The redundant manipulators have more DOFs (degree of freedoms) than it requires to perform specified task. The inverse kinematic (IK) of such robots are complex and high nonlinear with multiple solutions and singularities. As such, modern Artificial Intelligence (AI) techniques have been used to address these problems. This study proposed two AI techniques based on Neural Network Genetic Algorithm (NNGA) and Particle Swarm Optimization (PSO) algorithm to solve the inverse kinematics (IK) problem of 3DOF redundant robot arm. Firstly, the forward kinematics for 3 DOF redundant manipulator has been established. Secondly, the proposed schemes based on NNGA and PSO algorithm have been presented and discussed for solving the inverse kinematics of the suggested robot. Thirdly, numerical simulations have been implemented to verify the effectiveness of the proposed methods. Three scenarios based on triangle, circular, and sine-wave trajectories have been used to evaluate the performances of the proposed techniques in terms of accuracy measure. A comparison study in performance has been conducted and the simulated results showed that the PSO algorithm gives 7% improvement compared to NNGA technique for triangle trajectory, while 2% improvement has been achieved by the PSO algorithm for circular and sine-wave trajectories.

Open access

Abstract

Various developing countries are confronted with serious environmental difficulties due to excessive resource utilization and insufficient waste management system. In particular, construction and demolition waste poses a grave threat to the environment, contributing to escalating energy consumption, the depletion of landfill capacities, and the generation of harmful noise and dust pollution. Consequently, the research community is tasked with the daunting challenge of devising effective strategies to incorporate this waste material in producing concrete, without compromising the critical strength and durability characteristics. The investigation aims to attain the aforementioned objective by examining the effects of using recycled aggregates as a distinct partial replacement of 0%, 5%, 10%, 15%, and 20% on the compressive and split tensile strength traits, contingent upon 7 and 28 days of age of curing. Experimental test results show that the optimal concrete production is achieved when 10% of coarse aggregate is replaced with recycled aggregate, maintaining 98% of the materials compressive and split tensile strength. To further validate the obtained experimental data, model equations were derived through regression analysis and the framed model equation is further assessed for accuracy using error analysis. In this study, a MATLAB program was utilized for prediction of compressive and split tensile strength with five distinct network types and the Levenberg-Marquardt algorithm is used for optimization. A comparative analysis was conducted between the regression analysis values and the performance of the ANN modelling. The findings demonstrate that the Artificial Neural Network (ANN) serves as a highly effective model, offering significantly improved accuracy in predicting the optimal correlation between compressive strength and split tensile strength of concrete.

Open access

Abstract

This study has developed adaptive synergetic control (ASC) algorithm to control the angular position of moving plate in the electronic throttle valve (ETV) system. This control approach is inspired by synergetic control theory. The adaptive controller has addressed the problem of variation in systems parameters. The control design includes two elements: the control law and adaptive law. The adaptive law is developed based on Lyupunov stability analysis of the controlled system, and it is responsible for estimating the potential uncertainties in the system. The effectiveness of the proposed adaptive synergetic control has been verified by numerical simulation using MATLAB/Simulink. The results showed that the ASC algorithm could give good tracking performance in the presence of uncertainty perturbations. In addition, a comparison study has been made to compare the tracking performance of ASC and that based on conventional synergetic control (CSC) for the ETV system. The simulated results showed that the performance of ASC outperforms that based on CSC. Moreover, the results showed that the estimation errors between the actual and estimated uncertainties are bounded and there is no drift in the developed adaptive law of ASC.

Open access

Abstract

The Cyber-Physical and Vehicle Manufacturing Laboratory, a model Industry 4.0 laboratory, is applying new innovative solutions to improve the quality of education. As part of this, a digital twin of the lab was designed and built, where users can practice. In the virtual space, it is possible to apply the known robot motion types, and the tool centre and wrist speed have been measured virtually. Robot control tasks can be performed “offline” using parameters. This information can then be transferred to the actual physical robot unit. The stable diffusion 1.5 deep learning model generates 2D geometric shapes for trajectory, allowing users to perform unique tasks during education. The Google Colab cloud-based service was used to teach our rendered-type dataset. For the 3D simulation frame, we used V-REP, which was developed on a desktop PC equipped with an Intel Core i5 7600K processor, Nvidia GTX1070 VGA with 8 GB of DDR5 VRAM, and 64 GB of DDR4 memory modules. The following material describes an existing industrial six-axis robot arm and its implementation, which can be controlled and programmed while performing virtual measurements after integrating into a Cyber-Physical system and using deep learning techniques.

Open access
International Review of Applied Sciences and Engineering
Authors:
Wajahat Saeed
,
Muhammad Sohail Saleh
,
Muhammad Naqash Gull
,
Hassan Raza
,
Rafaqat Saeed
, and
Tahira Shehzadi

Abstract

With the escalating density of vehicles converging at road intersections, the surge in road accidents, traffic conflicts, and traffic congestion has emerged as a pressing concern. This research paper addresses these challenges by employing MC (manual control) techniques to mitigate encroachment issues at three selected intersections. These intersections were identified through a comprehensive analysis of the Ranking-based Instance Selection (RIS), enabling the design of suitable measures to facilitate smooth traffic flow and minimize the occurrence of crashes. In order to gather pertinent data, the study incorporates various parameters such as traffic volume, peak flow rate (PFR), traffic conflicts, accidents, and intersection inventory. Through the implementation of our proposed approaches, which involve both MC techniques and signalized operation, a supreme level of service (LOS) is attainable. Notably, our findings demonstrate a remarkable reduction in the volume-to-capacity ratio (v/c ratio) of up to 0.62. This paper thus serves as a significant contribution to the field of traffic management, offering practical insights for optimizing intersection design and effectively addressing the challenges posed by increased traffic density.

Open access

Abstract

Worldwide, precast and hybrid construction methods are becoming increasingly popular in the construction industry. But many problems occur during the fabrication, such as segregation, bleeding, scaling, plastic shrinkage, dust formation, honeycombing, sintering, high sorptivity, and high permeability and transportation. This problem may be caused by an ineffective curing process that affects the quality of concrete and construction. In addition, it provides inadequate and incomplete cement hydration that has a 20% negative effect on the desired properties of the concrete. Various researchers have demonstrated the components of self-curing lightweight concrete that can enhance strength and physicochemical properties, and address the above-mentioned issues. In this review, the role of the self-curing mechanism in lightweight concrete based on the various self-curing chemical admixtures such as polyethylene glycol (PEG), superabsorbent polymer (SAP), polyvinyl alcohol (PVA), sodium lignosulfonate and calcium lignosulfonate as self-curing agents are discussed in detail. Also, this paper briefly reports on the scope, significance, mechanisms, and tests for self-curing lightweight concrete. Overall, this review analyzes the possibilities of future research perspectives on self-curing lightweight concrete with sustainable materials and fibres with comparative technical information.

Open access

Abstract

Sensors are the main components in Cyber-Physical Systems (CPS), which transmit large amounts of physical values and big data to computing platforms for processing. On the other hand, the embedded processors (as edge devices in fog computing) spend most of their time reading the sensor signals as compared with computing time. The impact of sensors on the performance of fog computing is very great, thus, the enhancement of the reading time of sensors will positively affect the performance of fog computing, and solves the CPS challenges such as delay, timed precision, temporal behavior, energy, and cost. In this paper, we propose an algorithm based on the 1st derivative of the sensor signal to generate an adaptive sampling frequency. The proposed algorithm uses an adaptive frequency to capture the sudden and rapid change in sensor signal in the steady state. Finally, we realize and tested it using the Ptolemy II Modeling Environment.

Open access

Abstract

This study examines the economic optimisation of existing district heating systems. A new approach has been taken to solving a long-standing problem. The authors describe the input-output model of the system, the balance equations for the thermal equilibrium of the system, and the heat transfer system. From the balance equations of the series-connected system elements, the resultant heat transfer balance equation and the resultant power transmission equation are derived. In an example, the authors detailed how perturbations in some input variables can be corrected with other variables. The equations presented and the concepts introduced form absolutely new scientific results.

Open access

Abstract

Selecting the construction delivery method during the contracting period is one of the most important decisions determining the quality of large-scale infrastructure projects. Infrastructure projects have the most complex production processes in civil engineering. Infrastructure projects are among the most complex and resource-intensive endeavours in civil engineering due to their size, scope, multidisciplinary nature, regulatory requirements, financing challenges, environmental considerations, and the need for long-term planning and maintenance. Effective project management, collaboration, and a deep understanding of these challenges are crucial for the successful execution of infrastructure projects. Implementing such projects inevitably demands proper quality management throughout the project lifecycle. Two primary types of construction contracts are under implementation worldwide: Design-Bid-Build (DBB) and Design–and–Build (DB) contracts. In the Western Balkans region, both types of contracts are utilized for infrastructure projects, A noticeable trend is emerging toward transitioning from DBB to DB contracts. This paper provides a comprehensive analysis of quality management within the context of construction contracts with a focus on the roles and responsibilities of key stakeholders and how these factors affect the achievement of quality objectives while managing constraints related to cost and time. This research aims to improve construction practices by selecting an adequate type of contract for construction practices and ensuring successful project outcomes.

Open access

Abstract

In this study, nonlinear control design is presented for trajectory tracking of Tricopter system. A Fractional Order Proportional Derivative (FOPD) controller has been developed. The performance of controlled Tri-copter system can be enhanced by suggesting modern optimization technique to optimally tune the design parameters of FOPD controller. The Spotted Hyena Optimizer (SHO) is proposed as an optimization method for optimal tuning of FOPD's parameters. To verify the performance of controlled Tricopter system based on optimal SHO-based FOPD controller, computer simulation is implemented via MATLAB codes. Moreover, a comparison study between SHO and Particle Swarm Optimization (PSO) has been made in terms of robustness and transient behavior characteristics of FOPD controller.

Open access

Abstract

This paper introduces a stereoscopic image and depth dataset created using a deep learning model. It addresses the challenge of obtaining accurate and annotated stereo image pairs with irregular boundaries for deep learning model training. Stereoscopic image and depth dataset provides a unique resource for training deep learning models to handle irregular boundary stereoscopic images, which are valuable for real-world scenarios with complex shapes or occlusions. The dataset is created using monocular depth estimation, a state-of-the-art depth estimation model, and it can be used in applications like rectifying images, estimating depth, detecting objects, and autonomous driving. Overall, this paper presents a novel dataset that demonstrates its effectiveness and potential for advancing stereo vision and developing deep learning models for computer vision applications.

Restricted access

Abstract

Scour around the bridge piers is the main cause of bridge failure below any bridge pier placed within the waterways. It is more than hundred years back a number of researchers described the vortex shedding phenomenon and the resulting Aeolian tones from a circular cylinder. Since then there have been a large number of investigations dealing with various aspects of this phenomenon. In many practical works and situations, flow takes place around more than one obstruction and objects in close proximity. Invariably in all these cases, interference effects occur and the forces on the obstructions are much influenced by these effects. These effects play a key role in the structures like flow-induced vibration of TV and transmission towers, and in many other practical situations. In this research paper the changes in the flow field that occur due to the interference effects are shown, analysed and the results as given in literature are compared with the present experimental work. The features have been brought out in this paper mainly make use of stand and geometry of circular cylinders in close proximity and the flow part of geometry in side by side arrangement.

Restricted access
Pollack Periodica
Authors:
Nándor Vincze
,
Kristóf Roland Horváth
,
István Kistelegdi
,
Tamás Storcz
, and
Zsolt Ercsey

Abstract

As part of the energy design synthesis method, complex dynamic building simulation database was created with IDA ICE code for all family house building configurations for a considered problem. In this paper, the annual heat energy demand output parameter is considered to serve as basis of a building energy design investigation. The sensitivity analysis performed by Morris' elementary effect method was used. As the result of the sensitivity analysis of the output parameter, the most important input parameters can be identified, that influence the buildings' energy efficiency, that can support further building designs.

Open access

Abstract

The aim of the research was to carry out the One-at-a-Time sensitivity analysis of a tree burning experiment simulation with a novel fuzzy logic-based method. It was observed that the precent of the remaining tree is sensitive to the moisture content, the crown-base diameter and the tree height. The other variables, which are maximum mass loss rate, maximum heat release rate, and maximum temperature at the top of the tree are moderately sensitive or not sensitive to the selected parameters. The presented results can be used in sensitivity studies and wildfire simulations.

Open access

Abstract

This study uses a three-layer backpropagation neural network combined with particle swarm optimization to control the foamed bitumen in cold recycling technology. The foaming process of bitumen is non-linear and depends on dynamic temperature. By developing a neural network model, this study effectively captures the complex relationships between temperature, water content, air pressure, and the expansion ratio and half-life of foamed bitumen. The integration of particle swarm optimization enhances the accuracy and convergence of the neural network model by optimizing the initial weights. This optimization process improves the model's ability to predict and control the quality of foamed bitumen accurately. It serves as a valuable tool for the rapid development of high-quality cold asphalt design.

Open access

Abstract

This study targeted to investigate a type of excavation slurry by local available material in Najaf region. On the other hand, chief practises is supported the deep sides of foundation in particular pile foundation and, drilling oil wells. The results of slurries are checking, for seven properties, which includes the viscosity (apparent plastic and funnel Marsh), yield stress, density, acidity, and gel power (10–0 min). Which are 11.7367, 8.8733, 38.1667, 11.5467 mPa·s, 1.1045 kg m−3, 10.9067, and 11.2683 mPa·s, respectively. On the basis of the results tests for the above properties, that is possible to produce a product that conforms to the specifications of American Petroleum Institute specifications, and according to the requirements of the standard ACI 336.3R-93:2006 without additives. The rheological behavior improvement is achieved through the breakdown of the bundles of palygorskite fibers that normally make up the texture of these mudstones by increasing the time and speed of the shear force as soon as increasing the concentration of clay powder.

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Abstract

The paper deals with the capacitance of cylindrical two-dimensional capacitor which consists of Cartesian orthotropic dielectric material. The determination of the capacitance of capacitor with orthotropic dielectric material by a suitable coordinate transformation is reduced to the computation of capacitance of an isotropic capacitor. It is proven that the capacitance of a Cartesian orthotropic capacitor can be obtained in terms of an isotropic capacitor whose dielectric constant is the geometric mean of the dielectric constant of the orthotropic capacitor.

Open access

Abstract

Fair treatment of individuals in a scheduling task is essential. Unfairness can cause dissatisfaction among workers, faster obsolescence of work tools and underutilization of others. The literature's definitions vary, and there is no clear definition of general scheduling tasks.

This article explores fair scheduling through the lens of final exams, aiming to extend decision support system methodologies. It proposes a method based on Lipschitz mapping to measure fairness and presents a pseudo-algorithm for estimating optimal trend lines.

The model and the algorithm are demonstrated using the example of final exam schedules. In this way, two feasible solutions can be measured and compared in terms of fairness.

Open access

Abstract

Building information modeling is one of the trends in the modern construction industry. The use of 4D building information modeling in addition to 3D building information modeling improves project planning and leads to higher quality of the final product with minimal wastage of resources. In addition, 4D building information modeling allows creating visual effects that can be shown to clients before construction begins. The study describes the ways in which 4D building information modeling can be used, as well as some of the notable benefits. The level of awareness of this technology and the level of its use in construction practice are also described. The final part describes the main problems and tasks of this field and possible ways to solve them.

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Abstract

The role of building orientation in decreasing energy consumption for cooling purposes was examined in this study. A radiation analysis was performed during the early stage of the architectural design process on a proposed four-story apartment building located in Cebu. The building's performance was evaluated using the Grasshopper Ladybug plugin on a 3D model developed in Rhinoceros. Results indicated that the optimal building orientation that produced the lowest total radiation was situated at 290° from the center of the building, with a recorded value of 731,356 kWh m−2. Conversely, the building orientation that resulted in the highest total radiation was recorded at 210°, with a value of 755,596 kWh m−2. The analysis results were utilized to make informed decisions about building orientation based on environmental factors and surrounding areas. The use of computational design tools in the early stages of architecture design improves the process by enabling designers to optimize building performance and identify potential design issues early, thereby avoiding costly problems.

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Abstract

The Electronic Throttle Valve (ETV) is the core part of automotive engines which are recently used in control-by-wire cars. The estimation of its states and uncertainty is instructive for control applications. This study presents the design of Extended State Observer (ESO) for estimating the states and uncertainties of Electronic Throttle Valve (ETV). Two versions of ESOs have been proposed for estimation: Linear ESO (LESO) and Nonlinear ESO (NESO). The model of ETV is firstly developed and extended in state variable form such that the extended state stands for the uncertainty in system parameters. The design of both structures of ESOs are developed and a comparison study has been conducted to show the effectiveness of the proposed observers. Numerical simulation has been conducted to assess the performance of observers in estimating the states and uncertainties of ETV. The simulated results showed that both full order and reduced order models of ETV have the same transient characteristics. Moreover, the effectiveness of two versions of observers has been examined based on Root Mean Square of Error (RMSE) indicator. The results showed that the NESO has less estimation errors for both states and uncertainties than LESO.

Open access

Magaspartok állékonyságelemzése

Mérnökgeológiai modell alkotás és numerikus analízis egy magyarországi példán bemutatva

Slope Stability Assessment of High Banks

Engineering geological model and numerical analyses, an example from Hungary
Építés - Építészettudomány
Authors:
Fruzsina Kápolnainé Nagy-Göde
,
Eszter Horváth-Kálmán
, and
Ákos Török

A meredek és instabil lejtők komoly műszaki problémákat okoznak, felszínmozgások miatt veszélyeztetnek településeket és infrastrukturális létesítményeket. A tanulmány egy kritikus régióban, a Balaton-part közelében elhelyezkedő magaspartok stabilitásának vizsgálatát foglalja össze. A bemutatott lejtő stabilitáselemzését különböző szoftverekkel – Plaxis, Geo5 és Slide2 – végeztük el, és összehasonlítottuk a kapott eredményeket állékonyság szempontjából. A modellezésből kiderült, hogy a magaspartok stabilitása nem éri el a szükséges biztonságot. Két fő azonosított tönkremeneteli módot lehetett elkülöníteni, melyek közül az egyik a talpponti, kissé alámetsző, összetettebb geometriával jellemezhető körcsúszólap, míg a másik a lejtő tetején az eróziós folyamatok miatt bekövetkező kisebb mozgás, lokális tönkremenetel. A számítások eredményeképpen a biztonság növelhető, megfelelően kialakított monitoring rendszerek segítségével.

Open access

Abstract

This study introduces the Chaotic Particle Swarm Optimization as an innovative variant of the traditional particle swarm optimization algorithm, addressing the issue of particle swarm optimization getting trapped in local minima with a low convergence characteristic during later iterations. Chaotic particle swarm optimization incorporates principles from chaos theory to enhance the swarm's exploration and exploitation capabilities. By introducing controlled chaotic behavior, particles exhibit more diverse and unpredictable movements in the search space, leading to improved global convergence and escape from local minima. The proposed method has been implemented and evaluated on benchmark problems to assess its effectiveness. The integration of chaos theory with particle swarm optimization offers promising opportunities for developing robust and efficient optimization techniques suitable for complex and dynamic problem domains in various real-world applications.

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Abstract

The models compared in this study were applied to a catchment located in the western part of Slovakia in order to analyze and compare the amount of soil loss in different periods. Using of the empirical model universal soil loss equation, the average annual soil loss in the pilot basin was modeled for 2015–2020. The universal soil loss equation includes a topographic factor modeled using the USLE2D external model. In order to compare the empirical model and the physically-based model a continual sequence of individual rainfall events was created and used as an input to the physically-based EROSION-3D model. The results reflect different behaviors of erosion processes in a catchment together with a comparison between empirical and physically-based approaches.

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A kritikai regionalizmus negyven évének elméleti összefoglalása nemzetközi és hazai nézőpontból

A Theoretical Summary of the Forty Years of Critical Regionalism from the International and Domestic Point of View

Építés - Építészettudomány
Author:
Vilmos Katona

A jelen tanulmány célja a kritikai regionalizmus nemzetközi elméleti alapjainak és gyakorlatban alkalmazható elveinek ismertetése azzal a szándékkal, hogy a témában teljesebb ismereteket nyújtson, és azok megfelelően hasznosuljanak az épített környezet alakításának gyakorlatában. Célja továbbá, hogy az elméleti alapokat és gyakorlati elveket pontos meghatározásokon át kiterjessze a magyar viszonyokra, és ezzel a kritikai regionalizmus helyes értelmezését ösztönözze, megvizsgálva, hogy abból korunkban mi időszerű és folytatható. A tanulmány segítséget kíván nyújtani a hazai építészeti irányok közül annak az egynek a felismerésében is, amely magyar kulturális identitásunkra tekintettel van, és sajátunkként vállalható mind a hazai, mind a nemzetközi szakmai közösségben. Mindehhez a teljesség igénye nélkül, de a legfontosabb értelmezési irányok megjelölésével, a legnépszerűbb tévedések eloszlatásával és a legjelentősebb alkotók névsorának összegyűjtésével szeretnénk hozzájárulni.

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Abstract

In this study, suitable fly ash (FA) was selected for agricultural purposes according to combined characteristic soils and water. The two FAs from the Tuticorin Thermal Power Plant (FA-TTPP) and Sripathy Thermal Power Station (FA-STPS) and physio-chemical analysis of soil and water samples from the five different sites (1–5) in Viruthunagar district, Tamilnadu is made. X-ray diffraction analysis (XRD) of FAs showed that quartz (SiO2), mullite (Al6Si2O), and hematite (Fe2O3) are available that enhance plant growth. The Fourier-transform infrared spectroscopy (FTIR) results confirmed that Si–O–Si, Al–O–Si, HO–OH, and OH bonding present in the FAs support to meet the required plant nutrients in the soil. Scanning electron microscopy analysis (SEM) of FA-TTPP revealed compact microspheres with regular, smooth, and irregular textures while FA-STPS showed glassy, unshaped fragments that may help to improve the texture of field sites. Energy dispersive X-ray spectroscopy (EDX) analysis found that FAs have essential macro- and micronutrients to minimize the soil nutrient and thus help to improve plant productivity. Sites 1 and 2 have acidic soil conditions and are recommended to use both FAs since they are alkaline in nature. FA can improve the water-holding capacity of sandy loam soils of sites 2, 3, and 4 due to the presence of fineness content in FA. Site- 1 has iron deficiency which can be remediated with rich iron FA-STPS. It is recommended to use optimum FA based on soil and water to improve agricultural efficiency.

Open access

Abstract

This article aims at illustrating the major factors of construction firms' failure from the perspective of constructors. Thirty-seven (37) factors are illustrated in this article. The factors are divided under 3 groups: financial, managerial and external. The study used the field survey technique (questionnaire) to collect the necessary data that serves its purpose. Results illustrate that the top 5 contributors are: delay in collecting payments from owner (financial group), poor work experience (managerial group), bidding strategy (managerial group), local political conditions, low profit due to high competition (financial group). Results indicate that the top factors are internal factors which could be handled and controlled by the company itself. The results of this study are the first step towards identifying the problems of contracting companies in order to understand them and try to find solutions that will raise the level of companies and ensure their continuity and success.

Open access

Geiger-féle kábelkupola parametrikus vizsgálata

Parametric Analysis of a Geiger Cable Dome

Építés - Építészettudomány
Authors:
Richárd Joao Rosa
and
Krisztián Hincz

Egyre erőteljesebb igény jelentkezik a nagy alapterületű, belső alátámasztás nélküli térlefedések iránt. A különféle tartószerkezeti megoldások közé tartoznak a tensegrity szerkesztési elven alapuló kábelkupola-rendszerek, melyek a viszonylag egyszerű statikai viselkedésük és anyagtakarékosságuk mellett könnyű szerelhetőségük miatt is kedvező megoldást jelentenek. A kábelek nyomóerővel szembeni ellenállásának hiánya és a nagy elmozdulások okozta anyagi és geometriai nemlinearitás miatt azonban a hagyományos végeselemes eljárások nem alkalmasak a statikai analízis végrehajtására. A dinamikus ellazítás nevű, fokozatosan közelítő iteratív eljárás alkalmas a szerkezeti analízis elvégzésére. Ennél a módszernél elegendő az egyes csomóponti szabadságfokoknak megfelelő mozgásegyenleteket felírni és megoldani, nincs szükség a szerkezet merevségi mátrixának az előállítására. A kutatás célja egy dinamikus ellazításon alapuló numerikus modell létrehozása és kábelkupolák parametrikus vizsgálatának numerikus alapon történő végrehajtása. Az alkalmazott programkörnyezet a Rhinoceros 3D és annak Grasshopper almodulja, mely különösen alkalmas paraméteres vizsgálatokra. Az eljárásban a szabad paraméterek hatása, mint például a sugaras kiosztású szegmensek és a belső gyűrűk száma, a nyomott oszlopok hossza vagy az előfeszítés mértéke könnyen vizsgálható, ami komplex viselkedésű térbeli tartószerkezetek tervezésekor elengedhetetlen az optimális szerkezeti kialakításhoz.

Open access

Az elsajátítás értelmezése 20. és 21. századi térelméletekben, és egy vizsgálati keretrendszerének megalapozása

Interpreting Appropriation in Space Theories of the 20th and 21st Centuries, and Proposing a Framework for Its Practical Investigation

Építés - Építészettudomány
Author:
Gergely Hory

Tanulmányom az elsajátítás és a térbeliség kapcsolatának értelmezésével foglalkozik. Az elsajátítás olyan gyakorlatokat jelent, melyek során az ember birtokba vesz egy objektumot vagy helyszínt, és azt sajátjának tekinti. A dolgozatban kifejtem, hogy az elsajátítás mint jelenség alapvető téri jellemzőkkel bír. Rámutatok továbbá, hogy az elsajátítás koncepciója fontos elemét képezi Henri Lefebvre a tér társadalmi termeléséről alkotott elméletének. A Lefebvre munkásságát feldolgozó és továbbépítő szerzők eredményeinek felhasználásával az elsajátítás különböző értelmezési tartományait tárom fel: ezek szerint az elsajátításra tekinthetünk mint a környezet kreatív átalakítását és határok létrehozását előidéző gyakorlatra; mint várospolitikai kritikára; mint a spontaneitás megnyilvánulására; illetve mint jelentéstermelő médiumra. Ezentúl megvizsgálom, hogy az időbeliség hogyan képes befolyásolni az elsajátítás bármely aspektusát. A tanulságok felhasználásával célom egy olyan elméleti fogalmakat magában foglaló keretrendszer felállítása, mely az elsajátítás valós téri eseteinek kutatásához használható. Az épített környezetnek az elsajátítás gyakorlatain keresztül történő vizsgálatától azt várom, hogy az ember által megtapasztalt valóság számos összetevője közötti eddig ismeretlen összefüggésre világít rá.

Open access