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Abstract

As a result of rainfall in large quantities, the leachate generated under the municipal solid waste (MSW) is increased, which leaks to the groundwater aquifers and pollutes it. Accurate evaluation of leachate leaks levels has long been regarded as a problem in Iraq due to a lack of reliable data and costly measuring costs. This work proposes a novel fuzzy expert system to predict the pollution status of the underground water in sandy soils. The expert system consists of two subsystems; fuzzy logic system and crisp logic system. The expert system is trained using a data set developed by finite element analysis of sandy soil subjected to contamination materials.

Open access

Abstract

The mining industry, currently undergoing profound changes, is destined to play an increasingly important economic role in the province of Quebec, Canada. Activity in this sector, its real net impact on government tax revenue, the economy, society, and the creation of wealth, is the subject of much discussion. Occupational health and safety is a major preoccupation in the mining sector, in which considerable numbers of workers suffer workplace accidents or occupational diseases due to the use of industrial chemicals, compounding the problem of exposure to noxious substances that exist naturally in mines or are produced inevitably in the course of normal mining operations. Air in mines thus can become laden with a wide variety of chemical agents, in the form of suspended solids, liquid droplets, and vapors and gases. Long-term exposure to most of these agents can seriously harm the health of mineworkers. Prevention remains the key to avoiding the social and economic consequences of these hazards and will make mining a more attractive sector for investment and employment in Canada.

The principal focus of this study, presented in two articles, is to set a preliminary theoretical framework for categorizing chemicals in terms of their effects on the health of mineworkers throughout the various phases of mining projects. The objective is to decrease (over the long term) the number of occupational diseases due to the use of chemicals by raising awareness among employers and exposed workers in the mining sector.

This research was conducted in four phases. The first article presented a review of the literature [1] on the chemical aspects of health and safety in mining in the province of Quebec. In the present article, the findings on the recurrence of health problems attributable to chemicals encountered in mines and how these effects should therefore be ranked from an occupational health and safety perspective are presented. The results show that various forms of dermatitis are the most recurrent health and safety risk.

Open access

Revisiting the Geometry of the Transition Zone Using Filposh Squinches in Ardeshir Palace

A kupola és a kupoladob geometriájának vizsgálata az Ardesir palotában

Építés - Építészettudomány
Authors:
Elaheh Golzari
and
Péter Rabb

Iranians invented squinches to cover a square-plan space with a dome. Filposh, a type of squinch first found in Sasanian architecture, is a conical vault constructed in the transition zone’s corners to transmit the dome’s forces and weight. This technique can be seen in three halls of the Sasanian palace of Ardeshir. In this paper, the geometry of the transition zone using filposh squinches between a spherical dome and the square supporting walls in Ardeshir Palace was re-examined. A historical descriptive method was employed to analyse the main drawings of the halls from the nineteenth century to the present, and two hypotheses concerning the geometry of the transition zone were modelled and evaluated. As a result, the hypothesis that the dome’s cross-section intersects the chamber’s square plan is rejected. Furthermore, the claim that the transition zone’s square plan circumscribes the dome’s cross-section was discussed and proven.

Open access
International Review of Applied Sciences and Engineering
Authors:
Ammar Al-Jodah
,
Saad Jabbar Abbas
,
Alaq F. Hasan
,
Amjad J. Humaidi
,
Abdulkareem Sh. Mahdi Al-Obaidi
,
Arif A. AL-Qassar
, and
Raaed F. Hassan

Abstract

The demand for automation using mobile robots has been increased dramatically in the last decade. Nowadays, mobile robots are used for various applications that are not attainable to humans. Omnidirectional mobile robots are one particular type of these mobile robots, which has been the center of attention for their maneuverability and ability to track complex trajectories with ease, unlike their differential type counterparts. However, one of the disadvantages of these robots is their complex dynamical model, which poses several challenges to their control approach. In this work, the modeling of a four-wheeled omnidirectional mobile robot is developed. Moreover, an intelligent Proportional Integral Derivative (PID) neural network control methodology is developed for trajectory tracking tasks, and Particle Swarm Optimization (PSO) algorithm is utilized to find optimized controller's weights. The simulation study is conducted using Simulink and Matlab package, and the results confirmed the accuracy of the proposed intelligent control method to perform trajectory tracking tasks.

Open access

Abstract

An enterprise framework based on the philosophy research approach to Information System (IS) features a holistic view in an industry that allows room for technological advancement, an industry with increasing expectations and demands for IS drives towards a more integrated framework and rethinking of the concept of delivering insightful outcomes. The specific features of IS in this study focus on the information criteria for the daily assignment of the railway industry operations through an industry enterprise framework. The study objective is to provide a comprehensive understanding of emerging knowledge from structuring IS and enterprise framework stages and their mashup characteristics in designing a model-driven development framework. The outcome will be a design of a strategic performance framework for a typical strategic performance application as the most vital outcome indicators, to focus on understanding the baseline of technology revolution (Industry Revolution 5.0) achievement to measure the transformation expected and the railway industry evaluation, based on the year-on-year target will be established. The usage of decision-making systems and strategic applications has increased massively to fulfill various kinds of purposes for organizations, businesses, and individuals. In this case, a high-quality decision-making system and strategic application are required to ensure it provides the intended functionalities.

Open access

Város, lakókörnyezet, karakter. Fejezetek a budai Várnegyed történetéből című konferencia anyagából

Excerpts of the Conference City, Residential Environment, Character. Chapters from the History of the Buda Castle District

Építés - Építészettudomány
Author:
András Ferkai

A Magyar Tudományos Akadémia Építészeti Tudományos Bizottsága az Építészettörténeti, Építészetelméleti és Műemléki Állandó Bizottsággal együttműködve szervezte a 2022. május 12-én az Országos Levéltárban tartott tudományos konferenciáját a budai Várnegyed történetéről. A budai Vár területén zajló építkezések és bontások adták a tanácskozás aktualitását, melynek fő célja az volt, hogy a legavatottabb szakemberek – építészek, régészek, művészettörténészek – révén bemutassa a budai polgárváros fejlődését a 13. századtól a rendszerváltozásig. Az új kutatási eredmények ismertetésén túl, az előadók arra is felkérést kaptak, hogy tegyék mérlegre az egyes korszakok hozzájárulását a Várnegyed karakterének alakulásához: milyen értékeket hoztak létre, milyen hibákat követtek el, hogyan befolyásolták e zárt települési egység funkcióit, a benne zajló élet minőségét. Mindez hozzájárulhat ahhoz, hogy tárgyilagosabban ítélhessük meg, mi számít műemléki, építészeti vagy település léptékű értéknek, és hogyan kellene viselkednünk e területen, hogy ezen értékekből – és a Várnegyed karakteréből – minél többet megőrizzünk a jövő generációi számára.

Free access

A budai Várnegyed fejleszthetőségének városépítészeti vonatkozásai •

Történelmi városközpontok morfológiai adottságainak és rekonstrukciós folyamatainak összevetése

Questions at the Urban Scale on the Development of the Buda Castle District •

Comparing the Morphological Givens and Reconstruction Processes of Historical Urban Centres
Építés - Építészettudomány
Author:
Bálint Kádár

A budai Várnegyed rekonstrukciója a második világháború után visszaadta a Polgárváros középkori és barokk léptékét és értékeit, ezeket kulturális, lakó és turisztikai funkciókkal töltve meg. A magyar főváros egyetlen integráns történelmi negyedeként őrzi történelmünk és építészetünk lenyomatai mellett a városépítő polgárság emlékét is. Ebből a történelmileg predesztinált szerepéből a századforduló dualizmusában tapasztalt hatalmi központ építések hasonlóan próbálták kimozdítani, mint korunk hatalmi törekvései, léptékben és jelentésben egy nagyobb szerepet megpróbálva ráerőltetni a budai polgárvárosra. A kis léptékű mozgásokat kiszolgáló középkori eredetű morfológia terhelhetőségének objektív szempontjai mellett számos nemzetközi példa is bizonyítja, hogy csakis olyan kulturális és lakó funkciók tehetik megélhető és sikeres városrésszé a budai Várnegyedet, amelyek képesek együtt élni az értékes történeti rétegekkel és azok léptékével. Ez a tanulmány a háború utáni rekonstrukció és a Nemzeti Hauszmann Terv által ma véghez vitt rekonstrukciókat nem egymással, hanem más európai történelmi városközpontok morfológiai adottságaival és rekonstrukciós folyamataival veti össze. A Space Syntax analízisek kimutatták, hogy a középkori eredetű városszövetek minden európai városban a 19. századi szövet mellett izolált, ám gyalogos szempontból integráns térrendszerrel bírnak, amely nem alkalmas a modern városok igazgatási és termelési funkcióit befogadni, ám megfelel a kortárs 15 perces élhető város fogalmának és a turisztikai térhasználatnak is. Az ilyen városközpontok közül a második világháborúban megsérült városszövetek rekonstrukciói közül a budai Várnegyed háború utáni rekonstrukciója nem lóg ki, sőt, megelőzte korát. A mai vári rekonstrukciós beavatkozások az újjáépítések módszerében nem lóg ki más európai folyamatok közül, de funkcióiban, a rekonstrukció által megcélzott történelmi kor kiválasztásában, valamint a társadalmi igények figyelembevétele terén nem követi a mai trendeket.

Open access

Remodelling a Medieval Net Vault Construction •

Case Study: The Apse Vault in the Catholic Church of Andocs

Középkori hálóboltozat szerkesztés újramodellezve •

Az andocsi templom szentélyboltozata
Építés - Építészettudomány
Authors:
Eszter Jobbik
and
János Krähling

In the present study, we analysed the exact, laser-scanned geometry of the apse vault of the catholic church of Andocs. The written sources about this vault are very limited, however, the point cloud-based research could provide new details about the history of the building, along with the formerly used building techniques. For the analysis, we worked based on our three-step analysis process, established for net vaults. During the studying of the rib system, we reconstructed the probable original construction and building method, as well as the temporary supporting structures of the early 16th-century vault. The analysis of the individual ribs led us to conclusions about this vault, in the mirror of the widespread ideas of the topic’s technical literature, such as the “Prinzipalbogen” theory (all the ribs of a given net vault have the same curvature), or the principle of the longest route (the cumulated length of the ribs’ plan, which led from the impost to the crown with the longest possible route equals to the radius of the ribs’ curvature). Regarding the curvilinear rib elements, we presumed a likely fabrication method, based on contemporary research results. Mapping the webbing and the ribs, we concluded their building order, as well as the plausible masonry technique of the webs.

Open access

Abstract

A heat pipe is a heat conduction program that utilizes both heat permeability and regime shift concepts to transport heat effectively between 2 different lines. A heat pipe is made up of a pipe or tube and a base fluid. In practice, the heat pipe is poured into a mould that is compatible with the cooling media. These devices have found uses in a variety of fields, including space apparatus, solar energy systems, electronic equipment, and air conditioning systems, due to their simplicity of design and ease of manufacture and maintenance. Thermal performance improvement being the major concern in our project we researched different techniques. The heating surface area has a direct impact on heat transfer. Therefore, we have focused on heat enhancement by introducing grooves. Alongside we also considered using different materials for the pipe. At the end of our research, we are going to produce groove structure models with different materials and analyze them using ANSYS software and propose the best structures with highest thermal efficiency for different applications of heat pipes. This is an attempt to increase heat transmission in response to various material and structural changes. Heat transmission is improved with grooved heat pipes as well as heat transmission various with different types materials used in heat pipe.

Open access

Abstract

This paper compared the performance between Integer Order Fuzzy PID (IOFPID) and Fractional Order Fuzzy PID (FOFPID) controllers for inverted pendulum system as a controlling plant. The parameters of each controller were tuned with four evolutionary optimization algorithms (Social Spider Optimization (SSO), Swarm Optimization (PSO), Genetic Algorithm (GA), and Particle Ant Colony Optimization (ACO)). The comparisons were carried out between the two controllers IOFPID and FOFPID, as well as among the four optimization algorithms for the two controllers. The results of comparisons proved that the FOFPID controller with SSO has achieved the best time response characteristics and the least tuning time.

Open access

Buda, a keleties város

Buda, a City with Oriental Elements

Építés - Építészettudomány
Author:
Adrienn Papp

Az oszmán hódítással egy teljesen új kultúra jelent meg Budán, aminek az intézményi hálózatát ekkor kellett megteremteni. Budán semmi sem volt meg, amit egy oszmán elvárt városaitól, amire a mindennapi élethez szüksége volt. Nem volt dzsámi, Korán-iskola, fürdő stb., ezeket mind létre kellett hozniuk, és az intézmények épületeket igényeltek. A jelentős új épületek, melyek oszmán stílus szerint készültek, a külvárosokban jelentek meg, a Várhegy őrizte középkori megjelenését. A Várhegyen a középkori épületek új funkciót kaptak, oszmán intézményeknek adtak teret. Elsőként a templomokból kellet dzsámit csinálni, ami azok teljes belső átalakítását jelentette. Utána sorban megtalálták a többi feladathoz rendelhető helyet, középkori épületet használtak az iskolák, a közkonyha, a fedett piac számára. Amit mindenképp újonnan kellett még a Várhegyen is megépíteni, az a fürdő és a síremlék. Ezek mind szükségesek ahhoz, hogy egy oszmán város működjön, így azt látjuk, hogy a korszak legelején mindent megépítettek vagy átalakítottak, amire szükségük volt, jelentősebb változás csak új városnegyedek kialakulása miatt tapasztalható.

A vári házakba oszmánok költöztek, bár a 16. században még 122 család élt itt, a korszak végére gyakorlatilag teljesen elköltöztek a Várhegyről a magyar lakosok. A lakóházak kisebb átalakításokon estek át, jelentős bontást és teljesen új épületegyüttes kiépítését a pasa palota esetében figyelhetünk meg.

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Budapest 1944–1945-ös ostroma súlyos károkat okozott a budai Várnegyed épületállományában. Paradox módon éppen ez a pusztítás járult hozzá, hogy a negyed legtöbb épületében sikerült feltárni a középkor addig ismeretlen – gyakran jelentős – maradványait. A tanulmány fő célja bemutatni, hogy a műemlékes építészek milyen lehetőségeket láttak a sérült épületek helyreállítására, a korábbi állapot rekonstruálására, vagy az arra érdemes részletek bemutatására. Bemutatja e munka gyakran változó intézményes kereteit, legjobb szakembereit, és azokat az elveket, melyekben mindannyian egyetértettek az 1949-es törvényerejű rendelet alapján műemléki területként kezelt Várnegyedben. Ezeket rögzítette az első rendezési terv (1948–1949), melynek irányelvei (legfőbb érték a középkori-barokk polgárváros karaktere, léptéke és utcaképei) a legutóbbi időkig közmegegyezésnek örvendtek. A késő 19. század túlzott magasságú épületeinek felső szintjeit visszabontották, túl hangsúlyos architektúráját lecsendesítették. Az 1954-es részletes rendezési terv már a negyedben lakók igényeire is tekintettel volt, ám az üres telkek beépítését elég sematikusan szabályozta. 1948 és 1960 között számos műemlék helyreállítás elkészült, a foghíjak beépítése viszont csak 1957-től vette igazán kezdetét. Az a néhány példa, ami korábban megvalósult, semleges architektúrával igyekezett igazodni a műemléki környezethez. E gyakorlatnak a fiatal építészgeneráció vetett véget azzal a meggyőződéssel, hogy – ha minden kor a saját stílusában épített a vár területén – akkor a modern építészetnek is ezt kell tennie.

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Itáliai és német építőmesterek tevékenysége a budai polgárvárosban a török kiűzése után

Activities of Italian and German Master Builders in Buda After the Expulsion of the Turks

Építés - Építészettudomány
Author:
Ágnes Gyetvainé Balogh

1686. évi visszavívása után a romokból és az eleinte még falusias viszonyokból lassan, majd egyre gyorsuló ütemben született újjá Buda városa. Az Udvari Kamara idegenből jött, főleg német anyanyelvű, katolikus lakosokat kezdett betelepíteni, a mestereket kedvező feltételekkel csábítva Pest-Budára.

I. Lipót Venerio Ceresola császári építőmestert nevezte ki a budai erődítési munkálatok irányítására, aki már 1686 októberében belekezdett az újjáépítés megszervezésébe. Az ország különböző részeiből érkeztek építőmunkások, akik a kőfaragókkal társulva céhbe szerveződtek Ceresola vezetésével. A budai kőműves és kőfaragó céh 1690-ben jött létre, és működött a céhek 1872-es feloszlatásáig. E mesterek polgári kőművesmester megjelölése még más értelemmel bírt, ugyanis az építész szakmán belül ekkor a legmagasabb megszerezhető képesítés a kőművesmesterség volt, s ezt csak céhen belül és csak mestervizsgával lehetett elérni. A kőművesmester a tervezéstől a kivitelezésig jogosult volt az építés teljes folyamatának elvégzésére. Az építész vagy építőmester elnevezés csak címet jelentett, azaz hivatal- vagy rangjelző volt, mint pl. az uradalmi vagy kamarai építész címe.

Ceresola háztulajdonos is volt Budán, ő kezdte építeni a budai városházát, melyet később a 18. század folyamán a céh több tagja is bővített vagy átépített, köztük Hölbling János, Vogl Konrád, Nöpauer Mátyás. A céh tagjai közül kiemelkedik Hölbling János, aki Ceresolához hasonlóan császári építőmester is volt, az ő egyik munkája pl. a Zeughaus kivitelezése. Nöpauer Mátyás tervezte és építette az Erdődy-palotát, ill. az ő tulajdona volt a Hess András tér 3. sz. alatti Vörös Sün vendégfogadó is.

E céh tagjainak nevéhez az egyszerű barokk lakóépületektől kezdve templomok, kolostorok, középületek építése kötődik, nagyrészt ők építették újjá Buda városát, ami alatt nemcsak a felső város értendő, hanem a külvárosok is, ráadásul e céh mint főcéh tagjai jogosultak voltak az ország egész területén építkezni.

Open access

Abstract

As of 2020, the mining industry in the province of Quebec (Canada) has been providing 16,000 jobs, the majority of these in the north part of the province and in the Abitibi-Témiscamingue region. From the exploration phase to the mining site rehabilitation phase, numerous chemical processes are used, often involving some of the most dangerous substances used on industrial scales.

The hazards associated with many of these substances are in some cases not obvious, and symptoms of exposure may take years to appear. The risks associated with the industrial use of chemicals in Canada and abroad has long preoccupied health authorities, given the severity of the diseases that can occur. In Quebec, occupational diseases associated with exposure to industrial chemicals are reaching 1,500 cases per year.

The principal focus of this study, presented in two articles, is to set a preliminary theoretical framework for categorizing chemicals in terms of their effects on the health of workers throughout the various phases of mining projects. The objective is to decrease (over the long term) the number of occupational diseases due to the use of chemicals by raising awareness among employers and exposed workers in the mining sector.

This research was conducted in four phases. The present article contains the results of the first two stages, that is, a review of the literature to catalog the industrial chemicals used in mines and to list the potential effects of exposure to them, based on Safety Data Sheets. Eighty-five (85) chemicals used in at least one mining project phase and dozens of potential effects on worker health were identified. The rest of the study is presented in a second article [1]

Open access

Abstract

This article deals with balancing an autonomous motorcycle model along a straight line and curve lines. The dynamic model of the motorcycle balancing is described with an inverted physical pendulum loaded with torque. The torque is provided by the inertia of a rotor driven by a direct current motor. The lean angle of the motorcycle is measured by a smart sensor, which is the feedback signal for the linear quadratic regulator control system. The main purpose of this study is to compensate the error of the smart sensor. Controlling the necessary lean angle of the motorcycle during cornering is also addressed.

Open access

Abstract

The aim of the study is to determine the environmental conditions in the territory of the Myjava river basin (Slovakia) in order to analyze changes in the ecological stability from the first military mapping (1769–1784) until the present (2020). Except of the assessment of the ecological condition of the area, the stress factors of the territory were evaluated together with proposed measures according to the need to improve the current situation. The ecological prosperity of the landscape was evaluated based on the several methodologies used in Slovakia including coefficients of ecological stability. The results pointed to changes in ecological stability during the period evaluated, together with analyses of the stress factors that are currently affecting the territory researched.

Restricted access

Abstract

Dynamic contact and impact problems are widely applicable. An accurate solution method for these kinds of problems can be used in many fields of mechanical engineering (e.g., cutting metalwork, cogwheel drives, etc.). However, the proper handling of the contact is problematic, as there emerges a substantial amount of nonlinearity in the displacement field. Therefore, a spurious high frequency oscillation is present in the solution. These oscillations must be avoided, as divergence can easily occur in the contact algorithm due to them. In order to eliminate this effect, the applied numerical method must be chosen and set properly. In this study, a comprehensive guide is provided for the appropriate selection of the proper numerical method and its parameters.

Open access

Abstract

Dynamic contact and impact problems are widely applicable. An accurate solution method for these kinds of problems can be used in many fields of mechanical engineering (e.g., cutting metalwork, cogwheel drives, etc.). However, the proper handling of the contact is problematic, as there emerges a substantial amount of nonlinearity in the displacement field. Therefore, a spurious high frequency oscillation is present in the solution. These oscillations must be avoided, as divergence can easily occur in the contact algorithm due to them. In order to eliminate this effect, the applied numerical method must be chosen and set properly. In this study, a comprehensive guide is provided for the appropriate selection of the proper numerical method and its parameters.

Open access

Abstract

In the Hydraulic Laboratory of the Department of Hydraulic Engineering, Faculty of Civil Engineering, Slovak University of Technology in Bratislava the distribution of the flow velocity in a shaft intake structure was investigated on a physical model. The homogeneity of the flow velocity distribution in the intakes of turbines has a great influence on the turbine performance. Modern optical methods, particle image velocimetry and laser Doppler anemometry, were used to measure the flow velocity distribution in the model of the turbine intake. The particle image velocimetry method provides a record of the velocity field, while the laser Doppler anemometry method provides an accurate indication of the velocity at a given point. The flow velocity distributions in the examined profiles were measured by the particle image velocimetry and laser Doppler anemometry methods and the results were compared with each other.

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Abstract

In the Hydraulic Laboratory of the Department of Hydraulic Engineering, Faculty of Civil Engineering, Slovak University of Technology in Bratislava the distribution of the flow velocity in a shaft intake structure was investigated on a physical model. The homogeneity of the flow velocity distribution in the intakes of turbines has a great influence on the turbine performance. Modern optical methods, particle image velocimetry and laser Doppler anemometry, were used to measure the flow velocity distribution in the model of the turbine intake. The particle image velocimetry method provides a record of the velocity field, while the laser Doppler anemometry method provides an accurate indication of the velocity at a given point. The flow velocity distributions in the examined profiles were measured by the particle image velocimetry and laser Doppler anemometry methods and the results were compared with each other.

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Abstract

On the basis of elaborating the connotation of intensive city block, it is pointed out that the intensive structure organization is the key to realize intensive city block. The order complexity of the block structure is formed by the close connection, overlapping of elements, the depth difference and their compound association. This paper constructs the basic pedigree of block structure design from three levels of street configuration, plot organization and building layout, and forms the derivation and comprehensive application strategy of pedigree from the organic linkage and compound of each other.

Open access

Abstract

On the basis of elaborating the connotation of intensive city block, it is pointed out that the intensive structure organization is the key to realize intensive city block. The order complexity of the block structure is formed by the close connection, overlapping of elements, the depth difference and their compound association. This paper constructs the basic pedigree of block structure design from three levels of street configuration, plot organization and building layout, and forms the derivation and comprehensive application strategy of pedigree from the organic linkage and compound of each other.

Open access

Abstract

Algae are an evolutionary model of success and colonize all suitable ecological niches including building material surfaces that have favorable characteristics. In the last 25 years, building physics measures were developed to reduce water availability, especially on external thermal insulation composite systems.

Investigations into the influence of coating formulations have so far primarily focused on binder systems, biocides and hygrothermal properties. Research on the algal susceptibility due to the fillers is not to be found, but these regularly constitute a large proportion of final coatings. The present work investigates the influence of magnesium-containing fillers in the process of algal colonization of free-weathered façade coatings and a defense-strategy by water-activated pigment composition.

Open access
Pollack Periodica
Authors:
Athmar Thamer Naiyf
,
Fahad Mohanad Kadhim
,
Samah Falah Hasan
, and
Muhammad Safa Al-Din Tahir

Abstract

The aim of this study is to design a pylon with an engineering structure that gives it support and strength and manufacture a pylon characterized by low cost, lightweight, and bearing the patient's weight. This study designed two pylon models and fabricated by additive manufacturing techniques. The polylactic acid polymer is used as the filament for the 3D printing of pylons. A force plate and tensile test with finite element method simulation ANSYS software were applied to the pylons to evaluate their performance. The results showed that 3D printed pylon with Y-section has enough strength under stress and good safety factor, and the ability to bear a high patient load without buckling and exceed the requirements to become instead of the metallic prosthetic pylons.

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Pollack Periodica
Authors:
Athmar Thamer Naiyf
,
Fahad Mohanad Kadhim
,
Samah Falah Hasan
, and
Muhammad Safa Al-Din Tahir

Abstract

The aim of this study is to design a pylon with an engineering structure that gives it support and strength and manufacture a pylon characterized by low cost, lightweight, and bearing the patient's weight. This study designed two pylon models and fabricated by additive manufacturing techniques. The polylactic acid polymer is used as the filament for the 3D printing of pylons. A force plate and tensile test with finite element method simulation ANSYS software were applied to the pylons to evaluate their performance. The results showed that 3D printed pylon with Y-section has enough strength under stress and good safety factor, and the ability to bear a high patient load without buckling and exceed the requirements to become instead of the metallic prosthetic pylons.

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Abstract

With the rapid importance of high-performance energy modeling of buildings, whole-building energy simulation engines are rapidly used in the decision-making process. However, there are tens of engines in the market, which makes the choice of design engine very challenging. This article provides a comparison of the applications of whole-building energy simulation to predict a significant number of systems. As a result, the selected engines will be compared to establish their characteristics and abilities. Nevertheless, the focus will be placed on: generic criteria; envelope; lighting; service hot water; Heating-ventilation; and renewable systems. However, the authors found that an engine could be used extensively in one system and has limited capabilities in another system.

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Abstract

Concrete-filled steel tube columns are widely used in civil engineering structures due to their excellent ductility, energy absorption capacity, ultimate load-bearing capacity, and seismic behavior. In this paper, a numerical study modeling of eight lightweight concrete and conventional concrete filled steel tubes was carried out using ABAQUS software, and the lateral load-carrying capacity of square and circular steel tubes under cyclic load was compared. The quarter and one-third height of the tubes was filled with concrete with respect to the pier's height, to improve the base performance of the piers. The results show that the capacity of steel tubes filled with lightweight concrete increased by 40%–70% regarding energy absorption. The square tubes showed better performance than the circular tubes in terms of yielding load, yielding displacement, and energy dissipation.

Open access

Abstract

Concrete-filled steel tube columns are widely used in civil engineering structures due to their excellent ductility, energy absorption capacity, ultimate load-bearing capacity, and seismic behavior. In this paper, a numerical study modeling of eight lightweight concrete and conventional concrete filled steel tubes was carried out using ABAQUS software, and the lateral load-carrying capacity of square and circular steel tubes under cyclic load was compared. The quarter and one-third height of the tubes was filled with concrete with respect to the pier's height, to improve the base performance of the piers. The results show that the capacity of steel tubes filled with lightweight concrete increased by 40%–70% regarding energy absorption. The square tubes showed better performance than the circular tubes in terms of yielding load, yielding displacement, and energy dissipation.

Open access

Abstract

To estimate and model explosion pressure rise in closed volumes, industrial applications require a simple method. Ideal gas model is capable to assume pressure rise values to 10% above to initial pressure. However, most of the explosion venting devices opens higher than this pressure range.

Extension of ideal gas model was carried out in this paper. Authors made some experimental studies in 20 L explosion sphere at ambient temperature and atmospheric initial pressure, with propane-air mixtures at different concentrations between 2.8 and 6.3 vol%. They measured pressure values inside the chamber during explosion and recorded at 9,600 Hz. Based on experimental studies, authors extended ideal gas model application range to 1.5 barg.

Open access

Abstract

To estimate and model explosion pressure rise in closed volumes, industrial applications require a simple method. Ideal gas model is capable to assume pressure rise values to 10% above to initial pressure. However, most of the explosion venting devices opens higher than this pressure range.

Extension of ideal gas model was carried out in this paper. Authors made some experimental studies in 20 L explosion sphere at ambient temperature and atmospheric initial pressure, with propane-air mixtures at different concentrations between 2.8 and 6.3 vol%. They measured pressure values inside the chamber during explosion and recorded at 9,600 Hz. Based on experimental studies, authors extended ideal gas model application range to 1.5 barg.

Open access

Abstract

This study aims to select the suitable density of the material according to the mechanical properties needed by the 3D-printing application in which it will be used. 3D-printed carbon fiber filaments with different printing densities have been tensile, and a fatigue test was experimented with to find the mechanical properties. Furthermore, the modulus of elasticity, yield stress, and ultimate tensile strength of the material was determined by analyzing the stress-strain curves. The result shows that the parts printed with a high infill density give better mechanical properties, more time to build the object, more strength, and heavier weight than those printed with low infill density.

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Abstract

Accessibility is known as the ease of reaching destinations. The accessibility is determined by the spatial distribution of potential destinations, and the magnitude, quality, and character of the activities found there. However, modernization and the fast expansion of urban development transform cities' local cultural life from walkable accessible places to just car places. This has encroached into every corner of our urban environment today. In addition, the available services and systems to manage the pedestrian movement in the historic core are inadequate and inefficient, posing risks to both the traffic and the pedestrians. That affects the walkability for cities gradually. Hence, this paper aims to explore the main physical elements that contribute toward accessibility under three main categories (pedestrians, vehicles and public transport) as one of the walkability characters in Salt City in Jordan. Historical review, site analysis, and survey were the main methodology used in this study.

Open access

Abstract

Accessibility is known as the ease of reaching destinations. The accessibility is determined by the spatial distribution of potential destinations, and the magnitude, quality, and character of the activities found there. However, modernization and the fast expansion of urban development transform cities' local cultural life from walkable accessible places to just car places. This has encroached into every corner of our urban environment today. In addition, the available services and systems to manage the pedestrian movement in the historic core are inadequate and inefficient, posing risks to both the traffic and the pedestrians. That affects the walkability for cities gradually. Hence, this paper aims to explore the main physical elements that contribute toward accessibility under three main categories (pedestrians, vehicles and public transport) as one of the walkability characters in Salt City in Jordan. Historical review, site analysis, and survey were the main methodology used in this study.

Open access

Abstract

Cracking in composite steel-concrete bridge decks is a common problem in civil engineering. Before, or shortly after, the bridge is subjected to live loads; various levels of cracking can appear, mostly due to plastic shrinkage and temperature effects.

This paper presents an investigation of the behavior of cracked concrete in a composite deck slab of a railway bridge supported by steel girders using the finite element method. Eurocode 4-2 proposes a few simplified methods for calculating shrinkage and cracking effects in concrete. Through the proposed methods of analysis, an analytical simulation of a continuous composite steel-concrete bridge deck is performed and some practical recommendations for analyzing beam girders of this type are given.

Open access

Abstract

Cracking in composite steel-concrete bridge decks is a common problem in civil engineering. Before, or shortly after, the bridge is subjected to live loads; various levels of cracking can appear, mostly due to plastic shrinkage and temperature effects.

This paper presents an investigation of the behavior of cracked concrete in a composite deck slab of a railway bridge supported by steel girders using the finite element method. Eurocode 4-2 proposes a few simplified methods for calculating shrinkage and cracking effects in concrete. Through the proposed methods of analysis, an analytical simulation of a continuous composite steel-concrete bridge deck is performed and some practical recommendations for analyzing beam girders of this type are given.

Open access

Abstract

Metal injection molding has undergone great growth in the last years and is widely used in the manufacturing of small-sized and geometrically complex metal parts in high-volume production series in many applications. This paper makes overview of the integrity evaluation of metal injection molding production. Digital radiography can automatize the process of controlling various discontinuities inside the material, with sensitivity acceptable by the standard. Image processing through software Rythm Review 2.2, allows the detection of discontinuities in complicated geometric shapes. Tests were made on items with thicknesses 3 – up to 8 mm, with complicated geometry. The result is satisfactory in terms of localization and evaluation of defects in both dimensions and typology.

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Abstract

Metal injection molding has undergone great growth in the last years and is widely used in the manufacturing of small-sized and geometrically complex metal parts in high-volume production series in many applications. This paper makes overview of the integrity evaluation of metal injection molding production. Digital radiography can automatize the process of controlling various discontinuities inside the material, with sensitivity acceptable by the standard. Image processing through software Rythm Review 2.2, allows the detection of discontinuities in complicated geometric shapes. Tests were made on items with thicknesses 3 – up to 8 mm, with complicated geometry. The result is satisfactory in terms of localization and evaluation of defects in both dimensions and typology.

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Abstract

This paper presents an experimental work of using crushed glass mixed with the poorly graded sandy soil to investigate the possibility of shear strength parameters improvement using the direct shear test. The crushed glass is sieved and prepared for seven sets of percentages, the collected percentages of crushed glass represented a mix of glass retained on sieves No. 4, No. 8, No. 30, No. 100, and No. 200 and were added as a weight ratio of the sample for many cases. The main results of this work show that the mixing 10% of crushed glass for sieves No. 8, No. 200, and No. 50 increase the angle of internal friction of poorly graded sand (Ø˚) about 15%, 3%, and 29% respectively, and mixing 10% of crushed glass retained on sieve No. 4 decrease Ø˚ about 40%.

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Abstract

This paper presents an experimental work of using crushed glass mixed with the poorly graded sandy soil to investigate the possibility of shear strength parameters improvement using the direct shear test. The crushed glass is sieved and prepared for seven sets of percentages, the collected percentages of crushed glass represented a mix of glass retained on sieves No. 4, No. 8, No. 30, No. 100, and No. 200 and were added as a weight ratio of the sample for many cases. The main results of this work show that the mixing 10% of crushed glass for sieves No. 8, No. 200, and No. 50 increase the angle of internal friction of poorly graded sand (Ø˚) about 15%, 3%, and 29% respectively, and mixing 10% of crushed glass retained on sieve No. 4 decrease Ø˚ about 40%.

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Abstract

This study evaluates future hydrological alterations caused by climatic changes until 2100 using climate change scenarios. The indicators of hydrologic alteration software program assess predicted changes in flow characteristics and the degree of hydrological alteration obtained through a range of variability approach analysis. The study was performed on the Hron River basin in Slovakia, using the daily discharges from the observation period of 1981–2010 and a modelled scenario of daily discharges until 2100. The time period investigated was divided into three periods among which four ranges of variability approach analysis were conducted. The study results presented assume an increased incidence of drought in the summer months. In the winter months, the period of increased flows is expected to intensify.

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Abstract

This study evaluates future hydrological alterations caused by climatic changes until 2100 using climate change scenarios. The indicators of hydrologic alteration software program assess predicted changes in flow characteristics and the degree of hydrological alteration obtained through a range of variability approach analysis. The study was performed on the Hron River basin in Slovakia, using the daily discharges from the observation period of 1981–2010 and a modelled scenario of daily discharges until 2100. The time period investigated was divided into three periods among which four ranges of variability approach analysis were conducted. The study results presented assume an increased incidence of drought in the summer months. In the winter months, the period of increased flows is expected to intensify.

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Pollack Periodica
Authors:
Agus Pramono
,
Irida Markja
,
Klodian Dhoska
,
Parid Milo
, and
Endarto Yudo Wardhono

Abstract

The natural fibre containing cellulose as its main component that can be used as an alternative material to improve the strength of polymer composites. Paper focused on the determination of the best volume fraction of sugarcane fibre-reinforced polymer composites. Three variants of alkalization time were carried out. The highest average value of the tensile test results was obtained at an alkalization time of 1.5 h with a tensile strength of 41 N mm−2 and elongation correspond to 11.806% where the highest bending test results were obtained at an alkalizing time of 0.5 h with a bending strength of 24.89 N mm−2. The results of mechanical interlocking have been observed on macrostructure photo and at 1.5 h of alkalization are better than 0.5 h and 1 h of alkalizing time.

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Abstract

This manuscript proposes a novel adaptive restarting genetic algorithm-based solution approach for rescheduling generation-based congestion control. The generator sensitivity values are considered to select generators to participate in the congestion management. The efficacy of the suggested technique is demonstrated on a 39-bus New England system and a modified IEEE 30 bus system, and a comparative study with other optimization strategies are established. The findings produced with the suggested technique for congestion management better the outcomes obtained with different methods. The presented approach ensures a superior convergence profile by eliminating local minima traps. This method also assists the independent system operator in managing congestion more efficiently.

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Abstract

A major object of prosthetics fitting procedure his to provide the amputee with the greatest potential long-term rehabilitation result by providing the finest feasible design. The foot keel and ankle joint are two key components for transtibial prosthetic users. This essay's objective is to determine the effect of systematically altering the stiffness of prosthetic foot keel and ankle joint on standing in individuals who have undergone unilateral transtibial amputations. A balance analysis was carried out to select the optimal combination of prosthetic foot and joint. According to the findings, the medium foot and soft ankle joint is the best one for standing analysis.

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Abstract

The focus of this study is how Xiazhuang Village with high quality resources can achieve sustainable development in the new era by protecting and transforming vernacular architecture. Based on the layout of village, the characteristics of vernacular architecture and the ecological advantages of construction technology, this study puts forward the classification renewal and optimization design based on different buildings to solve the problems of village. Try to find a way to continue the historical context of vernacular architecture and satisfy the development of rural tourism at the same time.

Open access

Abstract

The focus of this study is how Xiazhuang Village with high quality resources can achieve sustainable development in the new era by protecting and transforming vernacular architecture. Based on the layout of village, the characteristics of vernacular architecture and the ecological advantages of construction technology, this study puts forward the classification renewal and optimization design based on different buildings to solve the problems of village. Try to find a way to continue the historical context of vernacular architecture and satisfy the development of rural tourism at the same time.

Open access

Abstract

Modern buildings in Algeria consume a huge amount of energy and deliver modest thermal comfort, due to their design which does not address the local climate conditions. In contrast, it is commonly recognized that vernacular architecture is climate-responsive and environmentally friendly architecture.

This study aims to assess the thermal performance of vernacular architecture in the hot and dry climate of the Ziban region, Biskra. It was achieved by describing the main passive strategies in this architecture, later performing field hygrothermal measurements on two different houses in this region. The results revealed that the thermal effectiveness of these vernacular houses depends on the interaction of all their vernacular passive strategies from architectural to urban scale.

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Abstract

Modern buildings in Algeria consume a huge amount of energy and deliver modest thermal comfort, due to their design which does not address the local climate conditions. In contrast, it is commonly recognized that vernacular architecture is climate-responsive and environmentally friendly architecture.

This study aims to assess the thermal performance of vernacular architecture in the hot and dry climate of the Ziban region, Biskra. It was achieved by describing the main passive strategies in this architecture, later performing field hygrothermal measurements on two different houses in this region. The results revealed that the thermal effectiveness of these vernacular houses depends on the interaction of all their vernacular passive strategies from architectural to urban scale.

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Abstract

The urban structure of Dombóvár has been transformed in recent centuries, and the protected buildings that once defined the town center, have been relegated to the periphery. Today, despite its rich architectural heritage, the Kakasdomb district is an area at risk of segregation. The key to the integration of the district into the existing urban tissue is the utilization of the protected buildings of the area including the former synagogue building. This paper examines the possibilities for the reuse of the synagogue based on the town development strategy and the perceptions of the remaining Jewish community, and the systematic modification of the settlement structure, together with the possibilities for the integration of the neighborhood.

Open access
Pollack Periodica
Authors:
Orest Voznyak
,
Khrystyna Myroniuk
,
Nadiia Spodyniuk
,
Iryna Sukholova
,
Oleksandr Dovbush
, and
Mariana Kasynets

Abstract

In this work, the actual aspect of the creation of comfortable climatic conditions indoors due to the compressed swirl compact air streams at an alternating mode is considered. The purpose of this article is the mathematical modeling of the swirl compact air jet and getting of the analytical equations for calculation air distribution in a premise at the condition of dynamic indoor climate in compressed conditions of a premise for providing comfort people well-being. A mathematical model of air supply with the swirl compact air jets in the room has been developed. A combinatorial-logarithmic method for the graphs approximating the dependence of the relative transverse velocity of a swirl compact air jet and the correction coefficient for compression and swirling on the relative transverse coordinate has been developed.

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