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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
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

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

Abstract

Food, water, and energy scarcity threaten India's future, and they must be addressed first. To meet the country's ever-increasing population needs, agricultural productivity must be expanded. For the crop-land suitability, we have studied an area of about 6,539 km2 in Vizianagaram district. The majority of the land is used for paddy agriculture (Kharif). The crop-land suitability has been evaluated based on the different parameters identified in that study area. “Remote sensing (RS)” and “geographic information system (GIS)” were combined for the crop-land suitability using nine parameters. The slope, elevation, rainfall, soil texture, lithology, groundwater, land use–land cover (LULC), TWI, and land surface temperature are the primary criteria used to determine the crop-land suitability in the Vizianagaram district (AP). Thematic maps were created using Landsat 8 images and SRTM DEM images from USGS Earth Explorer. Based on these maps and the influence of these parameters, we may assign weights to the parameters and then rank them, the Analytic Hierarchy Process (AHP) allowing us to identify which area is more suitable for good crop productivity and which is not. In this study, the soils are divided into four categories: low suitability, moderate suitability, high suitability, and extremely high suitability. The suitability index is found to be in the range of 0–55.2%, which indicates the lack of outstanding agricultural lands in the sudy region.

Restricted 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 study aims to examine the effect of hydrolysis degree (DH) on both antioxidant activity and functional properties of Acetes japonicus proteolysate (AP). Consequently, the AP showed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity (SA) and ferric reducing antioxidant power (FRAP) at DH of 66.7%. Whereas, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) cation radical (ABTS•+) SA and superoxide anion radical (O2 •–) SA of the AP peaked at DH of 75.8%. In addition, its strongest Fe2+-chelating rate was found at DH of 72.1%. In the pH range from 3 to 8, the AP showed solubility over 55% even after heat treating, foaming capacity (FC) of 5.7–80.0%, foaming stability (FS) of 2.9–77.0%, emulsifying-activity index (EAI) of 16.1–56.3 m2 g−1, and emulsifying stability index (ESI) of 12.4–156.7 min. The highest water-holding capacity (WHC) and oil-holding capacity (OHC) of the AP were observed at DH of 66.7% and 50.6%, respectively. This study enhanced value of the Acetes by producing antioxidant AP possessing functionalities.

Restricted access

Mennyit ér a biztonság? Biztonság mint a Magyarországra érkező német szenior turisták költését befolyásoló tényező

How much does security worth? Security, as a component for the tourism spending of German senior travellers

Scientia et Securitas
Author:
Csaba Bíró

Összefoglalás. A biztonságra evidenciaként tekint az utazó a desztinációválasztás során. Annak tartalma erősen szubjektív, egyénenként eltérő szintet képvisel. A COVID–19-járvány időszakában megvalósult kutatásunk válasszal kívánt szolgálni többek között arra, hogy az időskorú német utazók esetében mely faktorok határozzák meg leginkább a desztináció preferenciát, és ez hogyan tükröződik a költésükben. 2021. július–október között megvalósításra került személyes megkérdezés végső mintáját 347 fő (55+ éves) német szenior utazó adta. Az eredmények rámutattak, hogy a marketingtudomány által, általánosan homogénként kezelt fogyasztói szegmens további alszegmensekre bontható, tipizálható, továbbá a desztináció preferenciát esetükben leginkább az infrastruktúra minősége és a biztonság határozza meg.

Summary. Introduction: Tourism does not exist without security. In Maslow’s hierarchy of needs, security is the second most determinant aspect after physiological concerns. We consider that as an evident fact, thus the secure nature of a destination is an obvious expectation regarding travelling aspects. The measure and actual meaning of this latter component is quite subjective, thus it varies person by person. Security can be investigated from several aspects, so it is important to highlight that our sample was analysed in relation to health security concerns.

Investigation materials and methods: In our research, conducted during the period of the COVID-19 pandemic, we pursued to outline the role of security, as well as the so-called Corona-Protocol, which was established for prevention purposes regarding the chosen destinations in the case of elderly travellers, and to find out how it is reflected in their touristic spending. We conducted personal interviews (PAPI) between July and October 2021 with the participation of 419 people, whose final sample – after being filtered regarding age and nationality aspects – consisted of 347 German senior (age group: 55+) travellers. The survey was carried out on three locations within Hungary (Pécs, Kalocsa, Budapest) with the participation of coordinators.

Research outcomes: The received replies were analysed – at first, the 48 touristic variables were submitted to factor analysis, which helped in the allocation of main components. By the use of these main components, we identified further sub-segments (traveller types) within the segments, which gave a superb illustration about the inaccurate nature of the practice, when senior travellers are considered as a homogenous group. In the case of five clusters – despite similar age averages – we identified distinct characteristics concerning the aspects of qualifications, incomes and the measure of touristic expenses, while the priorities regarding destination expectations, security, infrastructure and pricing were also different. Despite their relatively weak explanation capacities, our outcomes – received by regression modelling – pointed out that regarding our sample, the measure of touristic expenses was mostly determined by the infrastructural quality of destination and security. Thereby we can answer the question how much the cost of security for German senior travellers is. Furthermore, another outcome was the realisation that different habitat locations within the same home country have significant impact on the spending of German senior travellers. Our research could constitute an appropriate basis for further research regarding the investigated subject and traveller segment.

Open access

A rendészeti felsőoktatás hallgatóinak dohányzási szokásai

Smoking habits of law enforcement college students

Scientia et Securitas
Author:
Ákos Erdős

Összefoglalás. Egyes korcsoportokban (pl. fiatal felnőttek) és szakmákban (pl. rendőrök) az átlagosnál magasabb a dohányzók aránya. A tanulmány célja a rendészeti felsőoktatási hallgatók dohányzási szokásainak és nikotinfüggőségük súlyosságának vizsgálata. Keresztmetszeti, kérdőíves vizsgálatot végeztünk az NKE RTK rendészeti hallgatói körében (n = 180). A nikotinfüggőség súlyosságát a Fagerström Nikotinfüggőségi Teszttel (FTND) és a Dohányzás Súlyossága Indexszel (DSI) vizsgáltuk. A válaszadók körében 81,1% a dohányzás életprevalenciája, 24,4% jelenleg dohányzó, 14,4% naponta dohányzik. Az FTND alapján a naponta dohányzók 96,1% enyhe/nagyon enyhe nikotinfüggő, míg a DSI alapján 73,1%-nak alacsony a nikotinfüggősége. A rendészeti felsőoktatás hallgatóinak dohányzása nem elhanyagolható probléma, ráadásul jelentős közegészségügyi és biztonsági aspektusai is vannak.

Summary. In some age groups (e.g. students) and professions (e.g. police officers), the proportion of smokers is higher than in the general population. The aim of this study is to assess the smoking habits and heaviness of nicotine dependence of Hungarian law enforcement students. A cross-sectional, web-based survey was conducted among law enforcement students at the Faculty of Law Enforcement of the University of Public Service (n = 180). The heaviness of nicotine dependence was measured by the Fagerstrom Test for Nicotine Dependence (FTND) and the Heaviness of Smoking Index (HSI). Respondents reported 81.1% lifetime prevalence of smoking, 24.4% were current smokers, and 14.4% were daily smokers. Based on the FTND, 96.1% of daily smokers had low/very low nicotine dependence, while based on the HSI, 73.1% of daily smokers had low nicotine dependence. Smoking among law enforcement students is not a negligible problem, and it also has significant public health and security aspects.

Open access

A többműszakos munkavégzés biztonsági kihívásai a rend- és honvédelmi szerveknél

Security challenges of multi-shift work in the police and military

Scientia et Securitas
Author:
Zoltán Szakács

Összefoglalás. A krónikus napközbeni aluszékonyság és a vele járó figyelemzavar igen gyakori panasz, amely jelentősen rontja a munkavégzés teljesítményét, az életminőséget, összetett mechanizmus révén gátolja a mentális funkciókat, gyakran vezethet – munkahelyi és közlekedési balesetek okozójaként – fatális következményhez is. A krónikus napközbeni aluszékonyság mint panasz mögött a krónikus alvás depriváció mellett az elsődleges alvászavarokat kell keresnünk.

Summary. Police and military service, at the appropriate level of care, require neuropsychological functions from the service provider such as constant vigilance, sustained attention and concentration, and the compulsion to make quick, responsible decisions. However, the service is often accompanied by difficult external conditions, such as monotony, harsh weather factors, or shift work, which place a heavy burden on the service provider.

In both police and military service, in addition to a varied shift schedule, we often expect special mental and physical performance from those serving. However, a multi-shift schedule breaks the circadian rhythm of service, causing metabolic and hormonal changes, and can have a profound effect on one’s behavior and one can remain deeply inferior to oneself during a given performance. Not everyone is adaptable to such conditions, especially those with primary sleep disorders. Therefore, it is particularly important to recognize those suffering from primary sleep disorders among multi-shift workers. People with severe obstructive sleep apnea have an abnormally high degree of daytime sleep and their attention, concentration, vigilance, work and cognitive performance decline significantly compared to their peers in multi-shift work conditions.

Much of the experience gained in the field of sleep disorders becomes a practice in the field of occupational health. One of our main goals was to make the diagnosis, treatment and screening of diseases belonging to this professional and scientific topic.

The Military Health Sleep Diagnostic Laboratory is tasked with screening out dyssomnia sufferers from performing under special multi-shift conditions.

During military service, in modern warfare, the importance of multi-shift work schedules, the continuous standby system, and work periods of different than usual duration and content have increased.

All of this has significantly changed the demands on human performance during waking hours and the role of sleep in regeneration, restoration, preparation. In parallel with these requirements, unwanted drowsiness and exhaustion also increased in everyday work, and manifested itself in errors and accidents during operational actions.

Sleep deprivation fundamentally affects cognitive areas such as speed of thinking, decision making, divergent thinking, executive functions, emotions, understanding humor, memory, morality, risk taking, and alertness. A number of special functions are associated with the prefrontal cortex. Judgment, decision making, impulse control, attention, and visual association are related to this part of the cerebral cortex. This area of the cortex is very vulnerable and, as a result of sleep deprivation, a disturbance of the functions represented here can be observed.

Sleep disorders severely and often unexpectedly limit mental and physical performance. They can cause serious confusion during training, exercise, and tactical and operational activities, so knowledge of them is important for prevention, interpretation, and effective therapy. Sleep disorders can occur in greater numbers due to the special conditions of police and military service.

Open access

What knowledge is essential for the future civil servants?

Report on participation in the Synergia transnational education program for civil servants

Milyen tudás fontos a jövő kormánytisztviselőjének a 21. században, és miért?

Scientia et Securitas
Author:
Zsóka Magyar
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.

Restricted 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.

Restricted 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

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.

Restricted 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.

Restricted access

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.

Restricted 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

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

The effect of processing parameters on microencapsulation of oregano essential with maltodextrin:gum arabic using a disk atomiser spray-dryer was evaluated. By means of response surface methodology, the feed flow rate and inlet air temperature were optimised. Powder yield, moisture content, essential oil retention, and antioxidant activity of microparticles were evaluated. The best conditions to produce microencapsulated oregano essential oil were 0.6 L h−1 for feed flow rate and 200 °C for inlet air temperature. With this combination a microencapsulated powder with 89.8% powder yield, 2.1% moisture content, 92.1% essential oil retention, 76 s solubilisation time, 12.9 g of water/100 g of dry matter, 0.3371 g mL−1 bulk density, 0.5826 g mL−1 tapped density, and 8.2 μm of average particle size was produced. The microencapsulation of oregano essential oil preserves the antioxidant and antimicrobial activities of its bioactive compounds.

Restricted access

Abstract

This study evaluated the effect of surfactant-assisted enzymatic extraction on the quality of tiger nut milk (TNM). TNM was extracted from tiger nuts using different concentrations of xylanase (0.010–0.100%) and Tween 20 (0.005–0.010%). The yield, stability, nutritional, antioxidant, and sensory properties of the samples were determined. The yield of TNM significantly increased, by 32.72–50.67%, following surfactant-assisted enzymatic extraction. Optimum yield and stability of TNM were obtained using 0.010% xylanase and Tween 20. Enzymatic extraction significantly increased total sugar and flavonoids, however, starch, dietary fibre, protein, carotenoids, lycopene, total phenolic content, and antioxidant properties reduced significantly. The incorporation of Tween 20 stabilised these parameters. There was no significant difference in panellists' preference for the control (sample extracted without enzyme and surfactant), enzymatically-extracted, and surfactant-assisted enzymatic extracted samples in mouthfeel and aroma, however, the surfactant-assisted enzymatic extracted sample was most preferred in colour, consistency, taste, and overall acceptability. Using surfactant-assisted enzymatic extraction could prove invaluable for the production of TNM.

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Abstract

Cultivation of specialty mushrooms on lignocellulosic wastes represents one of the most economical organic recycling processes. Compared with other cultivated mushrooms, very little is known about the nature of the lignocellulolytic enzymes produced by the edible fungus Calocybe indica, its enzymatic activity profiles during submerged and solid state fermentation. The intracellular activity of laccase (7.67 U mg−1), manganese peroxidase (7.48 U mg−1), cellobiohydrolase (5.46 U mg−1), and endoxylanase (4.21 U mg−1) was best obtained in C. indica on 14th and 21st day of incubation. The extracellular activity of laccase (11.57 U mL−1), lignin peroxidase (8.45 U mL−1), and endoxylanases (6.22 U mL−1) were found to be highest on the 14th day. Ligninolytic enzyme activity was substantial during substrate colonisation but quickly dropped during fruiting body development. C. indica, on the other hand, showed relatively modest hydrolase activity during substrate colonisation. The activity of hydrolytic enzymes increased dramatically when primordia formed and peaked at the mature fruiting body stage. The yield of the crude enzyme-treated wheat straw utilised for mushroom production was 52.47%. These findings showed that the activities of lignocellulolytic enzymes were regulated in line with developmental phase of growth of C. indica.

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Abstract

This study aims to formulate the optimal pectin-curcumin-lemongrass oil emulsion (PE) for coating of chicken fillet at 50:50%, 70:30%, and 90:10%, based on microbial growth inhibition, freshness consistency, and fat absorption during frying. Throughout the 7 days of storage, chicken fillet coated with 70:30% PE showed significant (P < 0.05) suppressive activity against psychrophilic bacteria (8.09 ± 0.00 log10 CFU g−1) compared to non-coated sample (8.27 ± 0.06 log10 CFU g−1). In contrast, 90:10% PE coating inhibited the growth of yeasts or moulds on chicken fillet at 8.24 ± 0.28 log10 CFU g−1, compared to non-coated sample (9.16 ± 0.14 log10 CFU g−1). The 70:30% PE coating showed a better fillet's toughness (18.30 ± 1.32 N mm−1 s−1) and firmness (1.49 ± 0.22 N mm−1) when compared to fillet without coating. After 7 days of storage, coated and uncoated samples showed the same total colour difference (E value) indicating PE coating preserved the texture of fillet and colour. Both coated samples (70:30% and 90:10%) reduced fat uptake during frying by 13.70%–14.25%. The application of PE coating at 90:10% was effectively functioned as an excellent coating to preserve the quality and safety of fillet.

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Acta Alimentaria
Authors:
M. Reyzov
,
M. Eftimov
,
S. Gancheva
,
M. Todorova
,
M. Zhelyazkova-Savova
,
M. Tzaneva
, and
S. Valcheva-Kuzmanova

Abstract

Metabolic syndrome (MS) is a serious health condition. The purpose of this study was to investigate the effects of polyphenol-rich Aronia melanocarpa fruit juice (AMFJ) on glucose tolerance, triglyceride levels, and adipose tissue in rats with MS induced by high-fat high-fructose (HFHF) diet. Fifty rats were allocated in 5 groups: control, MS, MS+AMFJ2.5, MS+AMFJ5, and MS+AMFJ10. In the course of 10 weeks, the control group was on a regular rat diet while the other groups received HFHF diet. During the experiment, control and MS groups were treated daily orally with distilled water (10.0 mL kg−1) and the other three groups – with AMFJ at doses of 2.5, 5.0, and 10.0 mL kg−1, respectively. In MS rats, glucose intolerance, hypertriglyceridemia, visceral obesity, and increased adipocyte size were observed. In AMFJ-treated groups, the serum glucose and triglycerides, as well as visceral fat and adipocyte size decreased significantly and did not differ from those of the control group. AMFJ at doses 2.5 and 5.0 mL kg−1 showed an anti-apoptotic activity in adipocytes, while at the dose of 10 mL kg−1 a pro-apoptotic effect was detected. In conclusion, AMFJ could antagonise most of the negative consequences of HFHF diet on carbohydrate and lipid metabolism in a rat MS model.

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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