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Authors: Munaf Fathi Badr, Ekhlas Hameed Karam and Noor Mohammaed Mjeed

Abstract

The objective of this paper is to present a proposed control model for the electromechanical damper mass spring system including the backstepping technique in comparison with the conventional proportional–derivative–integral (PID) controller unit to realize the best performance of the control systems. The suggested approach demanded the construction in laboratory arrangement of damper mass spring system which linked with electrical position sensor, and the theoretical work involved the derivation of the required mathematical equations in order to formulate the simulation models in Matlab software package. The obtained results show that the backstepping control technique provides the better performance associated with stable control system especially with increasing the value of selected mechanical load.

Open access

Abstract

In the recently published researches in the object localization field, 3D object localization takes the largest part of this research due to its importance in our daily life. 3D object localization has many applications such as collision avoidance, robotic guiding and vision and object surfaces topography modeling. This research study represents a novel localization algorithm and system design using a low-resolution 2D ultrasonic sensor array for 3D real-time object localization. A novel localization algorithm is developed and applied to the acquired data using the three sensors having the minimum calculated distances at each acquired sample, the algorithm was tested on objects at different locations in 3D space and validated with acceptable level of precision and accuracy. Polytope Faces Pursuit (PFP) algorithm was used for finding an approximate sparse solution to the object location from the measured three minimum distances. The proposed system successfully localizes the object at different positions with an error average of ±1.4 mm, ±1.8 mm, and ±3.7 mm in x-direction, y-direction, and z-direction, respectively, which are considered as low error rates.

Open access

Industry 4.0 from a few aspects, in particular in respect of the decision making of the management

/Will the new industrial revolution change the traditional management functions?/

Author: László Török

Abstract

The fourth industrial revolution, often identified as the terminology of Industry 4.0, more and more enforces changes and modifications from each participant of the socio-economic ecosystem. These enforced corrections concern the households, the governmental areas in different degrees, but the operation of the company sectors is rearranged most strongly by them. The study analyses this latter structure in the following respect: which are the most important supports of Industry 4.0 and what kind of competency elements are required from the employees and the management? According to the research data to be introduced, the domestic companies lag behind in preparations for the challenges raised by Industry 4.0; the international experiences are more favourable in this field. After—partial—review of the professional literature, the author concludes that the business sphere is in a condition before paradigm shift due to Industry 4.0. As per the analysis of decision-making based on digitalization, the question in the subtitle is answered—Industry 4.0 does not change fundamentally the traditional management functions of the company sector, but the decision-supporting applications based on digitalization must be learnt and applied. That statement seems to be founded that only company management, being able to live with decision making based on digitalization, can win competitive advantage.

Open access

Abstract

Today, the use of proportional-integral-derivative (PID) control units continues in many control applications due to their simple structure. In areas such as pressure, temperature, flow control, PID control element is used and many new methods are applied in adjusting control parameters. In this study, the LTR 701 Controlled Airflow and Temperature Experimental System was used to study the temperature and pressure control at different flow rates in the pipelines. In this control system, temperature was controlled with PID control element, pressure was controlled with PI control element, and reaction of control parameters at different temperatures and pressures were investigated. Also, temperature was controlled as cascade with PI element in elementary controller and P element in secondary controller. The manual adjustment method has been applied to adjust the control parameters. In addition, the experimental system is modelled in MATLAB-SIMULINK. On this model, simulation results showed that it is matching the experimental results.

Open access
Authors: Barhm Mohamad, Jalics Karoly, Andrei Zelentsov and Salah Amroune

Abstract

In this work a multilevel Computational Fluid Dynamics (CFD) analysis has been applied for the design of a Formula race car exhaust muffler with improved characteristics of sound pressure level (SPL) and fluid dynamic response. The approaches developed and applied for the optimization process range from the 1D to fully 3D CFD simulation, exploring hybrid approaches based on the integration of a 1D model with 3D tools. Modern mufflers typically have a complex system of chambers and flow paths. There are a variety of sound damping and absorbing mechanisms working to quiet the sound flowing through a muffler and piping system. Two calculation methods were selected for this study. The muffler has a complex inner structure containing perforated pipe and fiber material. Computer-aided design (CAD) file of the muffler was established for developing Finite Element Analysis (FEA) model in AVL BOOST v2017 and another commercial advanced design software (SolidWorks 2017). FEA model was made to monitor the flow properties, pressure and velocity. After the model was verified, sensitivity studies of design parameters were performed to optimize the SPL of the muffler. The software analysis results are included in the paper. Recommendations are made for obtaining smoother SPL curves for various measurement methods.

Open access
Authors: Mariam Achbal, Abdellatif Khamlichi and Fadoua El Khannoussi

Abstract

In this work, a numerical method is proposed in order to achieve design optimisation of phased array (PA) probes for the special application of defects detection in thin films. This approach relies on an extended Fourier-based model that was adapted to predict the two-dimensional ultrasonic displacement field taking place in a thin plate under individual excitation of PA probe elements which have arbitrary orientation with respect to the examined part surface. Excitation is applied through a fluid couplant and is operated at scheduled delays that are managed to enable emission of constructive pulses. This gives the possibility to steer sound waves towards a direction and to focalize the beam in a selected point. An optimisation algorithm based on the concept of pattern search that does not require evaluation of a gradient was used to find the best match in the multidimensional analysis space of possibilities including the elements orientation angles, the elements lengths, the inter-elements distances and work frequency. Optimisation was performed with the objective to maximize the displacement amplitude at the focal point while minimizing simultaneously the effect of beam side lobes. The results obtained by this approach reveal that focalisation can be achieved with enhanced features in comparison with previous algorithms assuming linear elements that are parallel to the surface of the plate.

Open access
Authors: Norbert Novák, Péter Miklós Kőmíves, Mónika Harangi-Rákos and Károly Pető

Abstract

The role of rural areas partly changed in the last decades. The countryside is still functioning as the main food producer of the world and this role became much more important because of the global population growth and because of the change in dietary habits. But other rural functions appeared just like recreation, health preservation, and on the other hand the different ecological functions' importance increased. The population living in the countryside is continuously decreasing as more and more people try to move into urban areas. One of the main aims of this article is to give a brief literature overview on the services needed in the rural areas in order to stop migration from the countryside to the cities. Based on extensive literature review the article summarizes the changing functions of the countryside and tries to list those developments which are needed to preserve rural population.

Open access

Abstract

In the building mechatronics research centre of University of Debrecen, Faculty of Engineering, a new laboratory has been designed, named “Cyber-physical and intelligent robot systems laboratory”. The possibility to design and test unique and platform-independent systems was among the main goals, hoping that the system itself and its advancements may later be used in manufacturing industries as well.

Fulfilling the needs of “Industry 4.0” is a challenging task, as it requires every single device (e.g. industrial robots) to be connected to the same network, where they may be monitored and controlled. However, there are some factors that limit this, such as the periodical “instability” that some machines have, caused by singularity points.

The following material studies these so-called singularities of a KUKA KR5 industrial welder robot placed in a robot cell, from an engineering viewpoint.

Open access

This study was conducted to assess the effects of 2,4-epibrassionolide (EBR) on mold decay caused by Rhizopus stolonifer and its capability to activate biochemical defense reactions in postharvest peaches. The treatment of EBR at 5 μM possessed the optimum effectiveness on inhibiting the Rhizopus rot in peach fruit among all treatments. The EBR treatment significantly up-regulated the expression levels of a set of defense-related enzymes and PR genes that included PpCHI, PpGns1, PpPAL, PpNPR1, PpPR1 and PpPR4 as well as led to an enhancement for biosynthesis of phenolics and lignins in peaches during the incubation at 20 °C. Interestingly, the EBR-treated peaches exhibited more striking expressions of PR genes and accumulation of antifungal compounds upon inoculation with the pathogen, indicating a priming defense could be activated by EBR. On the other hand, 5 μM EBR exhibited direct toxicity on fungal proliferation of R. stolonifer in vitro. Thus, we concluded that 5 μM EBR inhibited the Rhizopus rot in peach fruit probably by a direct inhibitory effect on pathogen growth and an indirect induction of a priming resistance. These findings provided a potential alternative for control of fungal infection in peaches during the postharvest storage.

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Microalgae are promising alternatives to sequestration of carbon and reduction of environmental problems, e.g. the greenhouse effect and industrial water pollution. Depending on the growth conditions, microalgae can differ in their metabolism products, leading them to grow at different rates. Intracellular reactions and nutritional requirements from cell metabolism, as well as biomass composition, may vary in function of the temperature. In this study, the biotechnological potential of three microalgae strains from the species was evaluated in terms of growth, biomass composition, fatty acid profile, and chlorophyll and carotenoids contents. Each of the three species demonstrated different potential depending on their metabolisms: Scenedesmus spinosus presented fastest growth and had the highest protein content (52.99%), Pseudokirchneriella subcapitata presented the highest content of lipid extracted (26.51%), and Scenedesmus acuminatus showed increased production of chlorophyll (5.25 mg l–1) and carotenoid (1.02 mg l–1) pigments.

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Consumer concern over artificial food additives has stimulated production of pigments from natural sources. The aim of this study was to examine the effects of process variables on the content of colour compounds (betaxanthin and betacyanin) in beetroot peel juice extracted by conventional method. In this research, the extraction processes were carried out according to the central composite design with different process variables. Quantitative measurements of the basic colour compounds in beetroot extract were performed using spectrophotometer. From our experiment, it was found that the most adequate extraction conditions, which gave the highest yield of colour compounds (952.5 mg l–1 of betaxanthin and 1361 mg l–1 of betacyanin), were extraction time 1 h, operating temperature 20 ºC, and solvent ratio 0.8 w/v. Being a conventional heating method, it is a simple and cost efficient process with relatively high yield.

Open access

Tomatoes (Solanum lycopersicon L.) are one of the most important and most widely consumed vegetables in the world. The fruit contains considerable amount of different phytonutrients such as carotenoids, tocopherols, and vitamin C. In the present work, effects of some abiotic factors on the concentration of phytonutrients were investigated in tomato cultivated in two different types of soil. It was found that the type of soil had slight effect on the most important vital nutrients, while the ecological factors, particularly precipitation and average temperature 3 weeks before harvest, were of significant influence on such nutrients. It was found that low temperature and high precipitation before harvest caused the levels of carotenoids, tocopherol, and vitamin C to significantly increase by 65%, 46%, and 28%, respectively.

Open access

Barberry is a native Iranian plant including species Berberis integerrima and B. vulgaris. Barberry fruit is used for preparing sauces, jellies, carbonated drinks, candies, food colour powders, jams, marmalades, chocolates, juices, and nectars. They are used as a natural food colorant rich in anthocyanins instead of harmful artificial ones. They contain polyphenols and antioxidants that reduce damage from free radicals and prevent chronic diseases and cancers. Barberry fruit extracts were encapsulated in maltodextrin by spray drying and Liposome Entrapment. The sizes of spray dried particles were reported 1–20 μm by SEM. Dimensions of empty and extract loaded liposomes (B. vulgaris and B. integerrima) were 18–28, 37–51, and 51–77 nm, respectively, by FE-SEM. The moist diameter of liposomes measured by dynamic light scattering (DLS) method at day 0 and after 6 months at –18 °C were as follows; empty liposomes: 163.9±2.23 and 378.90±4.98, liposomes loaded with extracts: 135.2±2.04 and 160.90±2.19 (B. vulgaris) and 113.4±1.83 and 144.20±2.01 nm (B. integerrima). Evaluation of thermal-oxidative decomposition from Differential scanning calorimetry (DSC) results at 0–45–90 days showed that the antioxidant activity and the onset temperature of the encapsulated extract was higher than the control. The extracts encapsulated in liposomes, especially B. integerrima extract, had better antioxidant properties.

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There is a great demand for developing efficient anthocyanins extraction related to each plant material. Conventional methods have been replaced by novel techniques, but they might remain attractive when combined with the latter. Anthocyanins extraction from fresh and dried red cabbage was investigated by maceration, ultrasonication, and with enzymes. Pre-treatments through drying determined an improved extraction with respect to fresh samples, freeze-drying emerging as the best method. Combined enzyme-assisted extraction with maceration resulted in higher yield by conducting several extractions (1078.8±12.5 mg/100 g DW). The kinetic studies revealed good stability of anthocyanins at 50 °C, while constant degradation at 80 °C. The rate constant k at 80 °C and pH 3.5 was 1.7 10–3 min–1 and the half-life time t 1/2 was 6.7 h. Thermal analysis evidenced heat-induced changes in particular for extracts undergoing pre-heating. These results are valuable for optimal processing conditions of anthocyanins-containing products.

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Xylanase plays an important role in the food, feed, and pulp/paper industry. Filamentous fungi have been considered as useful producers of this enzyme from an industrial point of view, due to the fact that they excrete xylanases into the medium. In this study, four fungal species belonging to different genera, i.e. Aspergillus, Cochliobolus, Pyrenophora, and Penicillium were isolated from different sources and compared for their ability to produce xylanase in submerged culture. The fungal species showed enzyme activity as determined by dinitrosalicylic acid (DNS) method. It was found that the two saprophytic Aspergillus strains, i.e A. terreus (Fss 129) and A. niger (SS7) had the highest xylanase activity of 474 and 294 U ml–1 at pH 7 and 8, respectively, in the presence of corn cob hulls after 120 h of incubation. The production of xylanase seemed to be strongly influenced by the interactive effect of initial pH on the fungi. Interestingly, xylanase was better produced by the saprophytic fungi of Aspergillus and Penicillium than by the plant pathogenic ones of Cochliobolus and Pyrenophora. This work provides additional information to support future research on fungi with different lifestyles for food industrial production of xylanase.

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Changes of edible oil quality factors and formation of 3-monochloro-1,2-propanediol fatty acid esters (3-MCPD-FE) during deep-fat frying in four different experiments (control, salt, pork chop, and chicken liver) with high oleic sunflower oil were compared in this study. Based on the results of investigated oil quality parameters, which were free fatty acid (FFA), anisidine value (AV), UV extinction at 232 and 268 nm (E232 and E268, respectively), and total polar material (TPM), only a modest deterioration of the frying oil was observed. As we expected, the 3-MCPD-FE content in the control samples did not reach the limit of quantification (0.1 mg kg–1), while the table salt itself caused a slight increase. The results of pork chop and chicken liver experiments were not statistically different from each other, after the third frying circle 0.52 and 0.39 mg kg–1 3-MCPD-FE levels were reached, respectively. Based on these values, the human exposure estimation resulted in a low risk.

Open access

The breadmaking quality of bug-damaged wheat flours with high protease activity (HPAWF) and low protease activity (LPAWF) was attempted to be improved by using sourdough (prepared by L. plantarum (SD1) and L. sanfrancissensis (SD2)) and liquid rye sour (LRS) in this study. The effects of sourdoughs (20 and 40%) and LRS (1 and 2%) on the protease activity of the HPAWF were determined by SDS-PAGE. Protease activity of HPAWF decreased with the addition of 40% SD1, 20% SD2, and both levels of LRS (1 and 2%) compared to a control sample. The HPAWF bread samples produced with LRS (1 and 2%) had higher volume (P<0.05) and bread quality as compared to sourdough applications. LPAWF bread sample was comparable with those of 40% SD2 added sample in terms of volume and hardness (N) values (P>0.05), while SD1 addition caused quality losses. The overall results suggested that addition of 2% LRS had promising results for improving bread quality flours that were damaged by suni-bug at low levels.

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Authors: R. Amiri Qandashtant, E. Ataye Salehi, A. Mohamadi Sani, M. Mehraban Sangatash and O. Safari

Probiotic food products are available at the supermarket commercially, but probiotic bakery products are much less in evidence. In the present study, methyl cellulose (2%), whey protein concentrate (2%), corn starch (1%), and soybean oil at 2, 4, and 6% were used for coating layer on the bulked bread surface, and then the quality properties were studied. The results showed that Lactobacillus rhamnosus GG, as probiotic component of the coating, immobilized in corn starch, whey protein, and methyl cellulose films had enhanced viability throughout shelf-life. The probiotics remained viable for 4 days, maintaining high viable cell number levels. Adding soybean oil at 6% concentration enhanced texture, sensory properties, and image index during storage.

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Authors: E. Horvath-Szanics, J. Perjéssy, A. Klupács, K. Takács, A. Nagy, E. Koppány-Szabó, F. Hegyi, E. Németh-Szerdahelyi, M.Y. Du, Z.R. Wang, J.Q. Kan and Zs. Zalán

The increasing consumer demand for less processed and more natural food products – while improving those products’ quality, safety, and shelf-life – has raised the necessity of chemical preservative replacement. Biopreservation refers to extended storage life and enhanced safety of foods using the natural microflora and (or) their antibacterial products. Chitinolytic enzymes are of biotechnological interest, since their substrate, chitin, is a major structural component of the cell wall of fungi, which are the main cause of the spoilage of food and raw plant material. Among the several organisms, many bacteria produce chitinolytic enzymes, however, this behaviour is not general. The chitinase activity of the lactic acid bacteria is scarcely known and studied.

The aim of the present study was to select Lactobacillus strains that have genes encoding chitinase, furthermore, to detect expressed enzymes and to characterise their chitinase activity. Taking into consideration the importance of chitin-bindig proteins (CBPs) in the chitinase activity, CBPs were also examined. Five Lactobacillus strains out of 43 strains from 12 different species were selected by their chitinase coding gene. The presence of the chitinase and chitin-biding protein production were confirmed, however, no chitinolytic activity has been identified.

Open access

Immature rice grain is one of the under-valued by-products of rice milling industry. In this study, it was aimed to investigate the effects of immature rice grain flour (IRGF) substitution to tarhana, which is a traditional cereal-based, fermented food product. IRGF was replaced by refined wheat flour at the levels of 0 (control), 30, 50, 70, and 100%, and the effect of this replacement on the contents of crude fat, ash, protein, dietary fibre, phytic acid, minerals, vitamins B1 and B2, tocopherols, γ-oryzanol contents and sensory properties were investigated. It was shown that stabilised IRGF remarkably improved nutritional properties of the end product without adversely affecting sensory quality up to 50%. In conclusion, it could be suggested that stabilised IRGF has a promising potential for many food applications due to being cheap, accessible, nutritious, and gluten-free.

Open access

Abstract

The sol gel method was used in preparing a series of A site partially substituted La1−xBaxCoO3 (x ≥ 0.1 ≤ 0.4) perovskite catalysts coded LBC1, 2, 3, and 4 and their potential as catalysts for soot oxidation were evaluated. The Brunauer–Emmett–Teller (BET), Inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAES), Thermogravimetric/Differential Thermal Analysis (TGA/DTG), X-ray analysis (XRD) were used in characterizing the prepared perovskite catalyst. The result shows that at (x≥ 0.2 ≤ 0.4), there was an increase in surface area when we compare it with that of x = 0. The increase in surface area helps in increasing the catalytic performance of the catalyst. Also, when evaluating the catalytic performance of the synthesized catalysts, it was observed that doping the perovskite catalysts helped in the general improvement of the catalytic performance for soot oxidation. The best performance in this research study with a T50 of 484 °C was observed at x = 0.2 catalyst (LBC2). This shows that the non-noble perovskite catalysts prepared in this research study has the potential to replace the noble metal based catalysts used presently in the diesel automotive industry.

Open access
Authors: G. Lizia Thankam and Neelakantan Thurvas Renganathan

Abstract

Though being an ancient trend, usage of the homogeneous material cement in the construction industry is steadily getting eradicated with the springing up of supplementary cementing materials (SCM). Metakaolin is an imminent mineral admixture extracted from the mineral ore kaolinite, which enhances the interfacial zone by more efficient packing at the cement paste-aggregate particle interface, thus reducing the bleeding and producing a denser, more homogeneous transition zone microstructure. This paper depicts the various repercussions of the pozzolanic material metakaolin in the fresh and hardened properties of concrete when replaced with cement in finite amount. Also, it states the behavior of high-performance concrete and self-compacting concrete with metakaolin.

Open access

Abstract

The inelastic buckling behaviour of different rectangular thin isotropic plates having a free edge is studied. Various combinations of boundary conditions are subject to in-plane uniaxial compression and each rectangular plate is bounded by an unloaded free edge. The characteristic deflection function of each plate is formulated using a polynomial function in form of Taylor–Maclaurin series. A deformation plasticity approach is adopted and the buckling load equation is modified using a work principle technique. Buckling coefficients of the plates are calculated for various aspect ratios and moduli ratios. Findings obtained from the investigation are found to reasonably agree with data published in the literature.

Open access

Abstract

Industry 4.0 is referred as the fourth industrial revolution that represents the information intensive transformation of industrial automation and manufacturing processes. Cyber-physical systems (CPS) are building blocks in Industry 4.0 and part of the Industry 4.0 vision. This paper presents a cyber-physical platform development and implementation strategy for Industry 4.0 applications. It has been considered a cyber-physical platform model (CPP) built upon hardware reconfigurable technology based on a Field Programmable Gate Array (FPGA) processor framework. The development strategy exploits the full benefits enabled by reconfigurable hardware, such as scalability of complex systems, platform-based design approach, adaptive processing, real-time constrains management, or high performance prototyping capabilities. The implemented experimental setup also combines major advantages of both the hardware and software platform-based design trends in Industry 4.0. In this endeavor, the used software toolkit comprises the entire system complexity as a high performance integration layer. The presented design method and implementation strategy can serve as rough orientation for future CPS research and development activities.

Open access

Abstract

Reliability is one of the most important criteria that characterize last generation digital systems. In a wide range of applications the required reliability level is achieved by using hardware redundant configurations. Perhaps their most common form is the triple modular redundancy (TMR) based on a majority voting structure. Researchers that use this strategy make a major assumption: in fault-free operation mode the outputs of these digital systems match in all. This paper proves that synchronization and matching in all the outputs of such systems is not such a trivial problem. In this endeavor FPGA-based (Field Programmable Gate Arrays) redundant topologies are considered for study and experiments. Upon these structures specially conceived redundant models have been developed and simulated. The results outline that synchronization of complex digital systems is a difficult engineering undertaking and any initial assumption should be managed with the adequate circumspection.

Open access

Abstract

Information management and sharing is an essential ingredient, but a difficult and challenging problem for disaster response management. This paper proposes an ontology as a model to organize and structure information in order to improve the information management and sharing in disaster response management. The ontology was designed and developed based on philosophically grounded foundational ontologies. It was also implemented in ontological languages and demonstrated and evaluated in a case study of the flood evacuation process. This paper also provides a systematic approach to develop a well-founded domain ontology that addresses both static and dynamic aspects of a given domain.

Open access

Abstract

The objective of this work is to investigate the rotary friction welding of AA1100 aluminum alloy with mild steel, and to optimize the welding parameters of these dissimilar materials, such as friction pressure/time, forging pressure/time and rotational speed. The optimization of the welding parameters was deduced by applying Response Surface Methodology (RSM). An empirical relationship was also applied to predict the welding parameters. Tensile test and micro-hardness measurements were used to determine the mechanical properties of the welded joints. Some joints were analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) in order to investigate the formation of intermetallic compound (IMC) layer at the weld interface. Experimentally, the tensile strength of the weld increases with increasing the forging pressure/time, while the low level of forging pressure/time allows the formation of an IMC layer which reduces the tensile strength of the weld.

Open access

Abstract

The use of energy in the world today is increasing with increase in population. The cost and availability of energy significantly impacts our quality of life, the health of national economies and the stability of our environment. The rapid depletion of fossil fuel resources on a worldwide basis has necessitated an urgent search for alternative energy sources to cater to the present day demands. In recent years there has been a significant global commitment to develop clean and alternative sources of energy such as solar and wind. Wind energy technology has been the fastest growing energy source because it is fairly distributed around the world and readily available for use. However, more penetration of wind energy into existing power networks has some impacts on the stability of the power system. Therefore, this paper studies and analyzes the stability of a power system with increasing wind penetration. The paper presents some analyses of a power system and the dynamic behavior which identify the issues that limit the large-scale integration of wind generators in a power system.

Open access

Abstract

Frequency Hopping Spread Spectrum (FHSS) communications utilizes a pseudo random code to spread the bandwidth of the data being transmitted over a much wider range than is required by the data. Due to the pseudo random nature of the carriers selected for transmission, the spreading and dispreading process must occur simultaneously to recover the transmitted data signal. This requires the receiver have knowledge about the instant the transmitter began transmitting and the propagation delay between the two. However, in real world systems, this information is unavailable to the receiver. The paper utilizes MATLAB Simulink to demonstrate a method of synchronizing the code clock at the receiver with the code clock at the transmitter. This fine alignment process is known as code tracking.

Open access

Abstract

Natural rubber (NR) vulcanizates were prepared from natural rubber and chitin using a two-roll mill. The chitin was extracted from crab shell waste obtained from a local market in Oron, Akwa Ibom State, Nigeria using the chemical extraction method. The effects of the chitin at different contents (0–40 phr) on the mechanical properties of the NR/Chitin vulcanizates with carbon black as reference filler have been investigated. The tensile strength of the chitin filled natural rubber (NCH), and the carbon black filled natural rubber (NCB) vulcanizates were found to increase with an increase in filler content to reach optimum at 30 phr after which it decreased. The hardness, impact and abrasion resistance properties of the NCH and NCB vulcanizates increased as filler content increases. The tensile strength and abrasion resistance of the vulcanizates containing blends of varying percentages of carbon black to chitin (CBCH) increased as more carbon black (CB) is introduced while the hardness and impact strength increased with increase in chitin content. However, carbon black filled vulcanizates showed better property enhancement than the chitin filler.

Open access

Abstract

The Szentgyörgyi-Horváth-house is one of the major historical buildings of Balatonfüred. The design of the reconstruction was preceded by detailed architectural historical study. The reconstruction of the building was realized by retaining the original structures. For the new function the building was equipped with an air-conditioning engine-room. The air conditioner is a significant source of noise for the apartments facing the courtyard of the building, due to its continuous operation. The acoustic examination of the enclosed yard was calculated with two different approaches. The distance-dependent approximation, which is usual for large halls, was approved. Building construction structures were determined based on the results to meet the acoustic requirements.

Open access

Abstract

Lifts are indispensable for the evacuation of mobility-impaired people from buildings in case of emergency. It is necessary to quantify the movement parameters of these people and describe the entire process using a suitable algorithm. The aim of the research was to quantify the times and speeds of movement for a person using a wheelchair and for an injured person. An experiment in situ was used. During the experiment, arrivals at the lift, cabin entries, and exits were monitored. The results include the times and speeds of a mobility-impaired person's movement. The experiments showed that a person using a wheelchair was slower than an injured person. The results can be used to expand computational models to account for the possibility of using lifts for evacuation.

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Authors: Mohammed S. A. Khedr, Mona F. Ali, Abdullah M. A. Kamel and Manal A. A. El-Ghanam

Abstract

This research will shed light on studying a terrazzo pavement in Prince Mohamed Ali Museum (the case study). The authors used visual inspection, stereo microscope, USB microscope, XRPD analysis, and SEM.EDX to identify its components, deterioration aspects and execution techniques. The XRPD and SEM.EDX results revealed that Portland cement was used in the three layers of terrazzo because of the detection of Hatrurite, Alite, Anorthite, Albite, Aragonite, etc. Many pigments were used in the topping terrazzo layer as; Goethite, Greenalite, Hematite, Azurite and Magnetite. The divider strips were made of brass alloy and the topping layer chips were prepared from basalt, marble and sea shells.

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Authors: Tomáš Mandičák, Peter Mesároš and Matúš Tkáč

Abstract

Construction project management is difficult process and important part of efficiency and productivity in construction industry. Currently, construction industry is increasing demands on technology, environmental and social construction parameters in the context of maintaining the balance of economic efficiency and sustainability of the construction and realization of buildings. Progressive technology as knowledge systems and building information modeling are the supporting tool for achieving this. Building information modeling is a progressive intelligent 3D model-based process that gives architecture, engineering, and construction professionals the insight and tools to more efficiently in planning, designing and buildings and infrastructure managing. Knowledge and building information modeling technology include a lot of functions and opportunities for better and easier way to achieve project goal and affect to construction project management process. Research discusses the issue of construction project management trough building information modeling and knowledge technology. The main aim of the paper is to analyze impact of these technologies on efficiency in construction project management.

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Abstract

The soil conservation service - curve number method is a globally used approach to simulations of surface runoff for its simplicity and applicability. Nevertheless, relevant simulations require proper setting of the model's components. This work focuses on optimization of initial abstraction ratio λ in the Husí potok sub-catchments in Czech Republic. Due to favorable morphology, the watershed is prone to flash floods and accurate modeling of surface runoff is of high interest. The analysis was conducted using pairs of discharge and rainfall measurements. The results outline that the traditional value λ= 0.2 is too high in this watershed and should be reduced.

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Abstract

This paper studies the presence effects of two or more adjacent structures on the tunnel responses and vice versa due to surface and underground traffic loads. The study is numerically carried out by using Finite element Plaxis2D software©. The obtained results demonstrate that the dynamical interaction between the tunnel and the structures is significantly influenced by varying the number and distance between the adjacent structures, the depth of the tunnel and the location of the traffic load. These results can be considered and used in realistic and practical cases and also to help build efficient and more comfortable construction projects.

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Abstract

The possibility of using mineral admixtures as a replacement for cement may reduce the carbon dioxide emission, which causes global warming and climatic changes on the environment. The objective of this study is to investigate the properties of early strength concrete produced with a constant replacement of alccofine (i.e. 25% by mass) and a new generation of chemical admixture that is Polycarboxylate ether. The constant dosage of alccofine and different proportions of polycarboxylate ethers are mixed in concrete and tested for workability and mechanical properties of concrete. Response surface method was applied to predict, validate and optimize the experimental data using regression equation. The results show that the performance of concrete improves with the addition of alccofine and Polycarboxylate ether into concrete.

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Authors: Mykola Sysyn, Vitalii Kovalchuk, Ulf Gerber, Olga Nabochenko and Andriy Pentsak

Abstract

Railway ballast tamping is one of the cost-expensive renewal and maintenance works of railway superstructure. The quality of ballast consolidation influences its resistance to residual deformations and long-term deterioration of track geometry. The process of ballast compaction along the sleeper under the vibration loading is complex and depends on many factors. The ballast flow processes under the vibration loading can produce both consolidation and un-consolidation of ballast material. The present study is devoted to the experimental investigation of ballast consolidation inhomogeneity. The method of ballast local consolidation measurement is proposed. The method is based on the velocity of impact wave propagation that is measured with device. The application of modern microcontroller and sensor techniques provided simple and reliable multi-point velocity measurements in a ballast layer. That enables well enough spatial resolution of ballast consolidation inhomogeneity. The measurement analysis has shown more than 4 times higher consolidation under the sleeper center than for unconsolidated ballast.

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Abstract

In the present study, the performance of concrete sandwich panel against fire and axial load has been considered. A finite element model of a sandwich wall is presented and evaluated the performance under different temperature (200, 400, 600 °C. The ratio of width, thickness and length of wall are constant and the axial load enters on the top of wall. The maximum displacement and stress in different models shows the capacity of wall is increased at high temperature. The displacement has dramatically increased at temperature loading of 800 °C and it has gained which shows poor efficiency of wall at high temperatures.

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Abstract

This paper discusses the control of the electric energy consumption in a household equipped with smart devices. The household consumption pattern is the result of a two-level optimization framework. The scheduling of the electric appliances is determined by the first optimization, receiving Time of Use tariffs proposed by the utility company. The scheduler considers the consumer's preferences on the powering on for each appliance.

Secondly a model predictive controller is developed to control the electric heating system based on energy constraints resulting from the appliance scheduling.

Simulations show the energy efficiency and an optimized electricity cost of the strategy proposed.

Open access
Authors: El Mehdi Echebba, Hasnae Boubel, Oumnia Elmrabet and Mohamed Rougui

Abstract

In this paper, an evaluation was tried for the impact of structural design on structural response. Several situations are foreseen as the possibilities of changing the distribution of the structural elements (sails, columns, etc.), the width of the structure and the number of floors indicates the adapted type of bracing for a given structure by referring only to its Geometric dimensions.

This was done by studying the effect of the technical design of the building on the natural frequency of the structure with the study of the influence of the distribution of the structural elements on the seismic response of the building, taking into account of the requirements of the Moroccan earthquake regulations 2000/2011 and using the ANSYS APDL and Robot Structural Analysis software.

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Abstract

A welded steel protective cover used for the heat treatment of steel sheet coils is investigated. The protective cover is made of austenitic stainless steel and consists of three main segments, welded together, which have 1400 mm height each. The plate thicknesses at the lower, middle and upper segments are different. The investigation aimed to improve the lifetime and the number of heat cycles of the protective cover by changing the geometry, the effect of the thicknesses and the material. Damaged covers have been evaluated, made calculations of stress and deformations, and carried out a series of finite element simulations. Both horizontal and vertical corrugated sheets were simulated and compared. The non-corrugated plates were also investigated, but their performance was behind the corrugated ones. The original geometry and that of the horizontal corrugated plate are identical from the stress level point of view. The vertical position of the corrugated plate provided a better result than the horizontal one. The calculated and simulated results for the original geometry are close to the measured damage.

Open access

Abstract

The mechanical and physical properties of the crushed aggregate have been studied. The properties of crushed aggregate, which produced from recycled aggregate concrete is not discussed in the literature yet despite it could be a choice in some circumstances like in case of demolishing the structures that already constructed by recycled aggregate concrete. Twenty-two types of self-compacting high-performance concrete made by coarse natural aggregate and coarse recycle concrete aggregate have been crushed and their properties have been studied. The main findings of the present study that, the Los Angeles index and water absorption of crushed aggregate is affected by the coarse recycled concrete aggregate dosage in its parent concrete, as well as, incorporating cement replacing materials in parent concrete help to enhance the abrasion resistance of crushed aggregate.

Open access

Abstract

The historic centers to retain their liveliness and vibrancy should be able to grow and change. It is a big challenge for the contemporary architecture to balance the socio-economic needs of the city and its community in one hand, and protection of the cultural heritage on the other. The aim of this study is to analyze the incorporation of the new structures in the historical context. How can the new structures harmoniously be incorporated in the historic centers without endangering their cultural heritage values? The paper discusses how to design a new contemporary shopping mall in the Historic Center of Prizren in order to create an attractive area and at the same time avoiding deterioration of the historical place.

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Abstract

Stability is one of the most critical problems in the design of welded metal structures, since in many cases instability causes failure or collapse of the structures. The present study aims to show the minimum mass design procedure for welded steel box columns loaded by a compression force. The normal stresses and overall stability are calculated for pinned columns. The dimensions of the box columns are optimized by using constraints on global stability, local buckling of webs and flanges. Different design rules and standards are compared: Eurocode 3, Japan Railroad Association, American Petroleum Institute, and American Institute of Steel Construction. The calculations are made for different loadings, column length and steel grades. The yield stress varies between 235 and 690 MPa. Optimization is carried out using the generalized reduced gradient method in Excel solver. Cost calculations and comparisons show the most economical structure.

Open access

Abstract

The article is presenting a consideration of the photogrammetry technology in the field of architectural usage. The technology overview is describing a basic knowledge to support the professionals. The processes, rules and best practices are examined through case studies, which introduce a dwelling house, an old precast concrete hall and a landscape surveying to cover most of the architectural usage. The purpose of the research is to give guidance for technical possibilities and assists in the development of the methodologies. The main part of the article is focusing on unmanned aerial vehicles as these tools provide many useful features.

Open access
Authors: Jana Smetanková, Peter Mesároš and Tomáš Mandicák

Abstract

Civil engineering industry represents important industry segment, which deals with building, performing and managing construction and business. In this sector, more and more pressure is generated for raising the effectiveness and productivity. Main tool, which supports the effectiveness and productivity, is process automation. Building information modeling represents intelligent process based on a model, which offers civil engineering specialists an overview and tools for effective planning, building blueprint, building management and infrastructure. Primary building information modeling goal is to create the uniform environment, which allows managing the life-cycle of building. Result of this work in enlisted environment is a multi-dimensional model, which carries all the information. This article deals with building information modeling issues, specifically with its dimensions and brings short description of each dimension and actual level of using the 5th dimension (cost estimating) in Visegrad Four countries. Level of 5D usage is demonstrated through surveys which were realized in Visegrad Four countries, and offers an overview of current implementation status in these countries.

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Abstract

Amongst different approaches, dynamic time warping has shown promising results during the online signature verification competitions of previous years. To improve the results of dynamic time warping, different preprocessing steps may be applied and different dimensions of the samples may be compared. The choice of preprocessing steps and comparing dimensions may significantly influence the results. Thus, to aid researchers with these decisions, a comparison made between the results of promising preprocessing algorithms as horizontal scaling, vertical scaling and alignment using dynamic time warping in different dimensions and their combinations on two datasets (SVC2004 and MCYT-100). The results showed that preprocessing methods made a very promising improvement in the verification accuracy.

Open access
Authors: David Honek, Zuzana Németová, Silvia Kohnová and Monika Šulc Michalková

Abstract

The modeling of soil erosion processes is affected by several factors that reflect the physical-geographic conditions of the study site together with the land use linkage. The soil parameters are significant in the modeling of erosion and also runoff processes. The correct determination of a soil's parameters becomes a crucial part of the model's calibration. This paper deals with a sensitivity analysis of seven soil input parameters to the physically-based Erosion 3D model. The results show the variable influence of each soil parameter. The Erosion 3D model is very sensitive to initial soil moisture, bulk density, and erodibility.

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Abstract

Decentralized wastewater systems treat, dispose and reuse the wastewater in the vicinity of source, reducing the sewage transportation cost to minimal. As an alternative to centralized systems it can function as a satellite system or an individual wastewater treatment unit. Design an onsite facility applies the same sizing procedure compared the conventional large scale systems, whereas the input flow data and its variability, the model parameters could differ. In this study a small size treatment unit was designed by biokinetic modeling, where the model parameters were estimated using analytical methods. As a result of the calculation the biomass build-up and the quality of the treated effluent was predicted and the operation parameters were determined in summer and winter operation.

Open access

Abstract

The paper discusses the theoretical background of the state space modeling of induction machines. The main goal is to present the necessary equations of the induction machine and the topic of the state space modeling. Although the induction machine is a highly non-linear system, LPV/qLPV model can be formulated from these equations.

Open access
Authors: Patrik Márk Máder, Dorottya Szilágyi and Olivér Rák

Abstract

Information-based modeling technology is supported by advanced information technology solutions in the building industry. The integration of its methodology into construction and design processes is already going on. However, many areas still have development possibilities; for instance, building surveys belong to these fields. Countless survey tools and methodologies endeavor to support and ease the work of professionals in design and construction, yet there is a need for comprehensive collaboration. This could be promoted by creating a direct link between survey tools and architectural design software.

This article demonstrates a tool under development that intends to provide a solution to this issue.

Open access

Abstract

Ensuring the provision of suitable living units remains one of the most challenging issues among the architects. The economic conditions in Kosovo represent one of the factors that influenced the functional and spatial change in multi-apartment buildings. Taking into account the passing of time, economic conditions, the requirements and needs of the communities change, those affects change in the functional and spatial aspect. The construction of multi-apartment and individual buildings, as well as other buildings with other uses in the center of the cities represents a delicate issue. On the other hand, the need for reconstruction and re-destination of usage of the existing residential buildings is becoming an important topic for the society in Kosovo. The issue is somewhat sensitive regarding the multi-apartment residential buildings, given that the usable surface is increasingly limited. The next challenge for the architects will be the treatment of the existing areas, their adaption in harmony with the requirements of the new generations, social changes that Kosovo is dealing with. The entire endeavor to reach a more comfortable solution is realized through treatment of the residential spaces not only in function wise, as well as in the exterior, through the transparence in architecture. The aim of the paper is to show transformation of the living spaces through real example, in Prishtina.

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The purpose of this study was to evaluate the ability of Lactobacillus rhamnosus to bind patulin (PAT) in the buffer solution and apple juice. The binding of L. rhamnosus to PAT was reversible, which improved the stability of the bacterial complex. The ability to bind PAT can be enhanced with the inactivation of the strain by high temperature and acid treatment. Acid-treated bacteria had the highest PAT binding rate of 72.73±1.05%. The binding rates of acid and high temperature (121 °C) treatments were increased by 21.37% and 19.15%, respectively. L. rhamnosus showed the best detoxification ability to PAT at 37 °C, where the binding rate reached 50.9±1.03%. When the dose of inactivated bacteria powder was 0.02 g ml−1, the minimum concentration of PAT in apple juice was 0.37 µg ml−1. The addition of the L. rhamnosus inactivated powder did not affect the quality of the juice product and effectively bound the PAT in apple juice.

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Authors: A. Sharma, S. Prasad, R. Arun Kumar, S. Jaiswal, P.K. Agrawal, L. Kant and J.C. Bhatt

The present paper reports that significant genetic variability was evident in Fe, Zn, β-carotene, and phytic acid (phytate, PA) contents in a set of 39 diverse maize genotypes collected from maize breeding programme of hill agriculture, India. The Fe, Zn, β-carotene, and PA concentrations were found to be in the range 19.31–50.64 mg kg−1, 12.60–37.18 mg kg−1, 0.17–8.27 µg g−1, and 6.59–7.13 g kg−1, respectively. The genotypes V335, V420, V393, V416, V414, V372, and V351 were identified to have higher concentration of β-carotene, Fe, and Zn but lower amount of PA. Possible availability of the minerals Fe and Zn was determined using molar ratio between PA as inhibitor and β-carotene as promoter for their absorption. The micronutrient molar ratio showed that Fe and Zn traits could be dependent of each other. Low R2 value revealed relation between β-carotene and kernel colour. The selected genotypes could be considered as potential sources of favourable genes for further breeding programs to develop micronutrient enriched maize cultivars.

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Four strains of Lactobacillus and Bifidobacterium including L. plantarum 01, L. fermentum D13, L. rhamnosus B01725, and B. bifidum B7.5 exhibiting naringinase production were applied in grapefruit juice fermentation. All investigated strains grew well in grapefruit juice without nutrition supplementation. In all cases, cell counts were 108–109 CFU ml−1 after 24 hours of fermentation. The highest lactic acid and acetic acid productions were observed in the case of strain L. plantarum 01. The L. plantarum 01 and L. fermentum D13 strains prefer glucose over fructose and sucrose, whereas fructose was the most favoured sugar for L. rhamnosus B01725 and B. bifidum B7.5. At the end of the fermentation process, antioxidant activity and total polyphenol content of grapefruit juice decreased in all cases, but the changes were not significant. Significant decrease of naringin was observed in the case of L. plantarum 01, 28% naringin in grapefruit juice was removed after fermentation. This result is promising for development of technology for production of probiotic grapefruit juice.

Open access

Globe artichoke (Cynara scolymus L.) is a perennial plant belonging to Asteraceae family. It is one of the most suitable plants for growing organically. Artichoke has been used as choleretic, hepatoprotective, anticarcinogenic, antioxidant, antibacterial, antifungal, antimicrobial, cholesterol-reducing, and diuretic in traditional medicine. Artichoke has been cultivated worldwide because of its nutritional value and medicinal properties. In this study organically and conventionally grown artichokes were compared in terms of phenolic constituents, antibacterial and antioxidant activities. Artichoke leaves, bracts, and floral receptacles obtained from 2 different sources (organic and conventional) were freeze-dried, powdered, and extracts were prepared with methanol. Phenolic constituents (chlorogenic acid, cynarin, luteolin, and apigenin) were analysed by HPLC-DAD system. It was found that organic farming enhanced cynarin, chlorogenic acid, and luteolin amounts in receptacle (edible part). Organically grown leaves had also higher amounts of cynarin and chlorogenic acid than conventional ones. Cynarin amount was higher by 35% in organic receptacle and 20% in organic leaves. Organic farming also augmented the antioxidant property and flavonoid content of edible parts of the artichoke. Additionally, organically grown leaves had the highest antioxidant activity, total phenol and flavonoid contents. Antibacterial activity was observed with both organic and conventional leaves only against Staphylococcus epidermidis. This comparative study revealed that organic farming enhanced the health-beneficial medicinal values of artichoke's heart and leaves.

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Authors: Á. Vajda, Cs. Mohácsi-Farkas, L. Ózsvári and Gy. Kasza

Salmonellosis is a widely known infectious disease in Hungary that played dominant role between 1960 and 1996 and remained one of the top food-borne illnesses to these days with an estimated total number of 96 048 cases (2019). Beside direct costs of treatment, indirect costs are also significant on the level of population. Among indirect costs, consumer well-being losses are difficult to be estimated. For this purpose, the willingness to pay (WTP) method is used most frequently that measures the cost an individual would undertake to avoid a certain harm. For the well-being loss estimation, the data of National Food Chain Safety Authority's annual consumer survey was used, in which 323 respondents gave evaluable answer to the open-ended WTP question. Results indicate that an average respondent would pay 18.6 EUR to avoid salmonellosis. Main factors affecting WTP were size of family and number of children. The numbers indicate that the consumer well-being loss could be about 1 786 060 EUR annually, resulting from the multiplication of the estimated number of annual salmonellosis cases and the average WTP value. It can be concluded that consumer well-being losses alone would call for further interventions in Salmonella eradication, not to mention other – more direct – cost elements.

Open access