bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of the vibration influence on load-bearing floor structures in case of machinery operation
Authors: Ilnytskyy B M , Kramarchuk A P , Bula S S , Bobalo T V
Published: December 2019

In this article, the impact of vibration loads on load-bearing floor structures is investigated. These loads were caused by machinery operation process in the five-storey factory building. Within this case study, examination of the structure was performed to measure the real vibration level and evaluate the damages to the structure. The analysis of the results has shown overloading the structures by machinery vibrations. The paper reflects a reasonable approach to rapid estimating of amplitude limits for floor structures avoiding complex calculations. Measured experimental values of amplitudes and precipitations under various productivity levels are given in this study. Theoretical and experimental data comparison appeared slabs subjected to vibration overloading and dynamic deflections. Some control points have shown significant exceeding amplitude limitations. Provided investigations of structure damages, in this case, also confirmed critical areas. It was revealed that incorrect machinery service entailed excessive vibration loads on the structures. Subsequent reinforcement works were provided to eliminate the cracks in structures.
Accounting of the dynamic pressure of bulk on the side surface in the world practice of designing building structures
Authors: Kalmykov Oleg , Khalife Rabie
Published: December 2019

This paper contains research of the seismic effects on the design of retaining walls. The present state of the technique of determining the pressure of the bulk medium on the side surface is analyzed. The basic theory of soil pressure on the retaining walls in static formulation is the Coulomb theory, according to which the pressure of the bulk medium on the lateral surface is determined by the condition of static equilibrium of a rigid wedge formed in the layer between the rear face of the structure and the sliding surface. In the works of Okabe and Mononobe, the proposed theory has evolved in the direction of dynamic influence accounting. To date, these studies are at the heart of current regulations. the issue of seismic component consideration in the calculation of retaining walls in the world design practice was analysed. The differences between the calculated dependencies of the US, Ukraine and Eurocodes codes are given. The reasons for the analyzed differences are identified and recommendations for their correction are offered.
Impact of low-cycle loads on deflections and width of crack opening of concrete beams with different types of reinforcement
Authors: Koval P M , Polyuha R I , Stoyanovych S V , Hrymak O Y , Komarov K O
Published: December 2019

The article presents the studies of the impact of low-cycle loads on experimental samples of concrete beams with different types of reinforcement – unstressed steel bars; steel pre-stressed reinforcement and unstressed reinforcement (mixed reinforcement); basalt-plastic reinforcement. Influence of low-cycle loads on the width of cracks opening and deflections of concrete beams were established. The research results of beams with steel reinforcement without pre-stressing, with pre-stressing and the beams with basalt-plastic reinforcement have shown interrelated proportional relative increase of the width of cracks opening and increase of deflections. Suggestions for consideration of the impact of low-cycle loads during the calculation of bending concrete beams reinforced with steel or basalt-plastic reinforcement by the second group of limit states were proposed. Coefficients determined experimentally for calculating the deflections and the width of cracks opening of the beams were introduced into the equation. Taking into account the impact of low-cycle loads during the calculation of bending concrete structures reinforced with steel or basalt-plastic reinforcement will provide higher reliability of such structures performance.
Methodology for assessment of the fire-resistant quality of reinforced-concrete floors protected by fire-retardant coatings
Authors: Kovalov A I , Otrosh Y A , Kovalevska T M , Safronov S O
Published: December 2019

In the work, the tests have been analysed for fire-resistant quality of hollow-core reinforced-concrete floors with fire-retardant plaster covering. A two-dimensional physical model and computer model have been developed in the ANSYS FLUENT software environment, which includes a system of equations and boundary conditions, taking into account the thermal conductivity in the coating and concrete, as well as complex convection-radiation heat transfer in air voids. A one-dimensional multilayer mathematical model has been developed, equivalent to a two-dimensional model of the thermal state of hollow-core reinforced-concrete floor with fire-retardant plaster covering, with the specific these layers’ thicknesses. A methodology has been developed in the article, based on solving the direct and inverse heat conduction problems, with the help of which it is possible to assess the fire-resistant quality of hollow-core reinforced-concrete floors with and without fire-retardant coatings. The developed methodology was applied to determine the thermophysical (heating constant and specific heating capacity per unit volume) and fire-retardant characteristics of the studied plaster covering according to the results of tests for fire-resistant quality of reinforced-concrete floors with this fire-retardant coating. The conclusion was made about the effectiveness of this coating and the boundaries of using the fire-retardant coatings to ensure normalizable values for the limit of the fire-resistant quality of hollow-core reinforced-concrete floors.
Deflections of continuous reinforced concrete elements
Authors: Krantovska O M , Ksonshkevych L M , Petrov M M , Synii S V , Ksonshkevych S M
Published: December 2019

The results of experimental investigations of deflections of continuous reinforced concrete elements are obtained, empirical dependences are deduced. Comparison of the deflection values with the results of calculations by the author’s method of NIISK (Bambura A.M.), adapted deformation model of OSACEA, what was realized with the help of the mathematical program MATLAB and also the algorithm of theoretical calculations of the finite element method was developed using the mathematical-graphical environment of the LIRA-SOFT software complex. The results of experimental investigations of deflections of continuous beams were compared with theoretical data (graphical representations of displacements in the form of isofields were obtained).The finite element calculation allowed to monitor the stress-strain state of the test beams at all stages of work, which made it possible to compare the obtained experimental values of the deflections with the designed ones. The performed experiments confirmed the feasibility of taking into account the shear deformations on the supporting sections in determining the deflections of reinforced concrete beams.
The research of carrying capacity of reinforced concrete walls under uneven warming
Authors: Nuianzin O , Tyshchenko O , Zhartovskyi S , Zaika P , Peregin A
Published: December 2019

The purpose of this article was to determine the dependence of the values of the boundary of the fire resistance of the bearing walls on the temperature dispersion on their heating surfaces as a scientific basis for improving the efficiency of the evaluation of the results of fire tests. In this paper, the problem of strength was determined to determine the bearing capacity of a reinforced concrete wall in a fire. During work, computational experiments using CFD and the finite element method were used. As a result of the studies, the dependence of the design values of the fire resistance of the reinforced concrete wall on the value of the maximum temperature dispersion on the heating surface of the structure during the fire tests and the error of the definition of the fire resistance limit was obtained, as well as the recommendations for creating new and improving existing furnace chambers from the tests on the fire resistance of the vertical reinforced concrete building constructions.
The criteria of estimating risks of spreading fire to adjacent building facilities
Authors: Nyzhnyk V V , Tarasenko O A , Kyrychenko O V , Kosiarum S O , Pozdieiev S V
Published: December 2019

The choice of heat flux receiver is justified in order to investigate the danger of spreading fire to adjacent building objects by the criterion of heat flux for measuring the heat flux density. It is suggested to use the heat flow receiver FOA-013-01. A technique was developed and experimental studies were conducted to determine the heat flux density acting on the elements of adjacent building sites. Measurements of heat flux values were performed by FOA 013-01 heat detectors, which were installed at distances of 2 m, 4 m and 6 m from the fire torch at a height of 1 m. The obtained heat flux density is, on average, for a distance of 2 m - 6.5 kW/m2, for distances of 4 m and 6 m - 1 kW/m2. Such data indicate a significant variability in the heat flux density over the observation period. Thus, experimental data call into question the possibility of using the “heat flux” criterion from a fire as a reliable criterion for evaluating the risk of fire spreading between adjacent building facilities. It has been suggested that the temperature criterion should be the basis for determining fire distance.
Estimation of fire resistance of bending reinforced concrete elements based on concrete with disperse fibers
Authors: Vasilchenko Alexey , Doronin Evgeny , Chernenko Oleksandr , Ponomarenko Ivan
Published: December 2019

The results of estimative calculations of bearing capacity, critical temperatures, and fire resistance ratings of reinforced concrete bending elements based on fiber concrete with disperse reinforcement of steel, basalt and synthetic fiber are presented. The calculations carried out on the example of a reinforced concrete rectangular beam both taking into account the percentage of reinforcement of each element and at a constant load corresponding to the condition of calculation adequacy showed that disperse reinforcement of a reinforced concrete bending element with steel, basalt and synthetic fiber increases its bearing capacity, but slightly affects critical temperature and fire resistance rating. Despite the fact that concrete with basalt fiber is the least sensitive to heat, concrete with steel and synthetic fibers turned out to be comparable in this indicator with ordinary concrete. The presented results of evaluative calculations allow predicting the use of bending reinforced concrete elements based on concrete with disperse fibers in conditions of increased fire hazard, depending on the percentage of reinforcement and on the workload.
Research of “influence area” parameters of the foundations arranged without soil
Authors: Zotsenko M L , Vynnykov Yu L , Pinchuk N M , Manzhalii S M
Published: December 2019

New relationships of shapes, sizes and properties formation for soils of the “influence area” of foundations and artificial bases, arranged without excavation, have been determined. The “influence area” parameters are decisive in assessing the stress-strain state of the system “base – foundation”. Field and laboratory methods of soil properties research of the “influence area” were improved: penetration; probing; rotational slip. A method of constructing the compaction area boundaries is considered, taking into account the shape, dimensions of the foundation cross-section and longitudinal profile, the type and properties of the base soil. For the first time, it is established that for soils with an angle of internal friction φ < 25°, the boundaries of the compaction area and the “influence area” are close to each other. When φ > 25° the boundaries of the “influence area” exceed the boundaries of the compaction area as more, the more the angle of internal friction of the soil. The relationship between the volume of the leading well and the soil compaction area diameter was also determined.
Physical and chemical research of the microstructure of the cement composite filled with allumosilicate and glass microphases
Authors: Bondarenko D O , Plakhotnikov K V , Kostuk T O , Dedenyova O B , Kalinin O A
Published: December 2019

Using the physical and chemical analysis, the possibility to obtain a dense and crack-resistant Portland cement-based composite material filled with aluminosilicate and glass microspheres and a complex additive which purposefully enhances each of the mentioned properties have investigated. During the molding of a composite material, in which particles of a filler and a binder have the same size in microns, micro-reinforcing fibrous additives will not be effective because their particles are larger than filler’s particles. To specify the conditions for the formation of a micro-reinforcing layer of etryngite needles and for increasing the density of the cement matrix structure, relevant theoretical and experimental studies were carried out and a complex additive consisting of calcium nitrate and chloride, carboxymethylcellulose and plasticizer was proposed. Based on the physical and chemical analysis performed, it has been found that adding a complex additive facilitates the compacting of the cement matrix structure through the additional synthesis of crystalline hydrates: ettringite, calcium hydrochloroaluminate, calcium hydroxychloride, and calcium hydrosilicates of the felt-like structure, which improves physical and mechanical properties of a Portland-based composite material.
Production of modified basalt fibre for heat-insulating products manufacturing
Authors: Gots V I , Berdnyk O Y , Rogozina N O , Maystrenko A A
Published: December 2019

As a result of the research flexible heat-insulating materials were developed based on basalt fiber with increased effectiveness, which can be achieved due to directed fiber microstructure forming through fusion modification. It is known that chemical composition of initial fusion not identically influences on physical and chemical and mechanical properties of basaltic fibres. Structural descriptions of fusion and basaltic fibre got from him appear main factors the nearer, than high speed of cooling. This index mainly depends on such constituents: a) ambient temperatures; b) coefficient of heat conducting; c) heat conducting of fusion; d) areas of surface. By researches influence of temperature of basaltic fusion was shown on the structure of fibres. Structural characteristics of the basalt fiber (number of active zones, coefficient of its distribution on the basalt fiber surface, as well as a correlation of three groups of active zones) depend on rheological properties of basal fusion, speed of drawing through the die plate and cooling speed.
Study of service properties of alkali-activated cement using wastewater treatment residues
Authors: Kovalchuk Oleksandr , Kochetov Genadiy , Samchenko Dmytro
Published: December 2019

The paper discloses the results of the study of treatment of galvanic wastewater residues by incorporation into the alkali-activated cement matrix. Leaching of heavy metals from the artificial stone was studied. It is set that immobilization level of the matrix is 99.96 % by mass of heavy metal (97.83 using traditional methods). Application of alkali-activated cement makes it possible to obtain compressive strength of compound up to 40 MPa even when 30 % of wastewater residues are involved. Immobilization level of alkali-activated cement matrix met requirements of the standard.
The effect of sodium aluminate on the properties of the composite cements
Authors: Kropyvnytska T P , Kaminskyy A T , Semeniv R M , Chekaylo M V
Published: December 2019

The effect of sodium aluminate activator on properties of the Portland-composite cement (clinker factor 65 %) was studied and the results are being discussed. It is shown that the introduction of sodium aluminate (Na[Al(OH)4]) leads to an increase in the water demand of cement and a decrease in its strength. The results showed that the sodium aluminate and polycarboxylate ether (PCE) admixtures ensure the production of higher strength cements. It has been found that the addition of Na[Al(OH)4] – PCE significantly increases the compressive strength of cement mortar, particularly at 10–48 h of hydration. XRD and SEM measurements confirm that the hydration of composite cement with the addition of Na[Al(OH)4] – PCE is greatly accelerated by the way of formation of intense lines ettringite. It has been shown that the introduction of a sodium aluminate into the cement mortars allows to accelerate hardening and increase early strength and using of composite cement will provide improved performance and suitability. The results have shown that alkaline accelerator and polycarboxylate were effective for decrease shrinkage of composite cements.
Disperse reinforced concrete with polycarboxylate additive on a mechanically activated binder
Authors: Ksonshkevych L M , Barabash I V , Krantovska O M , Synii S V , Sunak P O
Published: December 2019

The article discusses the properties of disperse reinforced claydite concrete on mechanically activated slag-portland cement with the addition of polycarboxylate superplasticizer Relaksol-Super PC. The idea of making a high-mobile claydite concrete mix with a settling of concrete cone 45 to 50 cm is substantiated. Particular attention is paid to the study of the effect of mechanical activation of the binder on the kinetics of the increasing in the strength of claydite concrete. The results of researches indicate that introduction of basalt fiber into slag-portland cement together with mechanical activation of binder allows to increase the impact strength of concrete by almost 1.7-1.9 times in comparison with the reference and to provide frost resistance of concrete at least than 350 cycles of alternating freezing and thawing.
Stabilization of the soil bases contaminated with peracetic acid
Authors: Levenko H M
Published: December 2019

The solution of the urgent problem, which is connected with the substantiation and development of the method of fastening of soil bases, acidified by industrial flows of food industry enterprises, is formulated and substantiated. It was established that in the food industry widespread use was made by washing and disinfectant Oxonia Active-150 on the basis of 25 % peracetic acid. This substance as a result of leakage and sewage emissions, getting into the soil basis, reacts with the chemically active substances of the soil, which leads to swelling of the base. It has been found out that the most effective way of stabilizing the behavior of soils of the bases contaminated with industrial effluents is the injection methods of fixation, in particular, silicification. It is established that for today there is no method of fixing soils contaminated with solutions of peracetic acid, which would solve the problem not only improving the mechanical characteristics of contaminated soils, but also would take into account the environmental aspect of the problem. For this purpose, the main approaches to solving the problem of fastening and ecological cleaning of soils contaminated with solutions of peracetic acid have been developed and substantiated. A scientifically and experimentally grounded method for calculating the chemical fixation of soils, which are prone to contamination with solutions of peracetic acid, is proposed. The model of the grounded choice of method of fastening and clearing of soils, which takes into account all requirements, which are advanced to arrays of fixed soils, is offered. The basic technological and chemical criteria for choosing a method for fixing a contaminated soil mass are determined.
On the issue of water activation for Portland cement
Authors: Nikolaev A P , Kondrachenko E V , Kondrachenko V I
Published: December 2019

The articles is devoted to the problem of Portland cement activity increase by changing its mixing water structure due to mechanical, magnetic, electromagnetic and certain other treatments. Known facts are analyzed on specific condition and behavior of cement grout liquid phase which is determined by the effect of crystalline field of the surface of cement minerals. The authors substantiated that this condition is more important for cement behavior under hardening than the consequences of eventual structural changes in its pretreated mixing water. An original method for controlling the hardening of cement paste based on measuring the hardness of cement samples is proposed. The method allows you to control the behavior of the material itself without taking into account the influence of the size and shape of the analyzed samples.
Mechanism of formation of microstructure of thin-layer coating based on Portland cement
Authors: Plakhotnikov K V , Demina O I , Bondarenko O I , Plakhotnikova I A , Miroshnichenko S V
Published: December 2019

Coatings based on mineral binders with inorganic hollow microfillers are effective thermal insulation materials. However, they have poor physical and mechanical characteristics, and this prevents from their extensive practical use. The purpose of the work is to develop the composition of a thin-layer thermal insulation coating based on Portland cement with addition of a complex additive intended to improve its physical and mechanical properties. The use of this additive facilitated the additional on-surface synthesis of microspheres of crystalline hydrates in the form of aggregate gels, ettringite needles and laminar structures, as well as the compacting of the structure of a thin-layer thermal insulation coating with crystalline hydrates formed during the clinker aluminate phase. These structural changes contributed to the improvement of physical and mechanical parameters of the thermal insulation coating.
The role of the crystallo-chemical factor in the evaluation and improvement of the nanomodification efficiency of mortar and concrete
Authors: Pushkareva K K , Gonchar O A , Kaverin K O
Published: December 2019

The article presents a new approach to the control of the processes of structure formation of binder systems, taking into account the achievements of nanotechnologies. The possibilities of managing the structure of the material at the nanoscale and the micro-level by introducing primary nanoscale additives or forming nanoscale objects in the bulk of the material are considered. The peculiarities of contact zone formation and microstructure of artificial stone based on nanomodified Portland cement and alkaline binder systems are investigated. The role of the crystallo-chemical factor and its influence on the strength formation of all levels of concrete structure are shown. It is proved that when using micro silica modifying additives, their efficiency at the micro level is higher than at the meso- and macro-levels. At the same time, the modification of the binding systems by artificial zeolites provides a more pronounced effect in concrete at the macro-level – due to the crystallo-chemical similarity of additives, products of hydration and minerals of the aggregate. Taking into account the crystal-chemical similarity of the new formation opens new possibilities for the choice of nano additives, considering not only the principle and nature of their action at the level of nanoscale and microstructure, but also the influence on the peculiarities of the formation of the contact zone at the meso- and macro-levels, which will have a decisive influence not only on the strength, but also on the special properties of concrete.
The electric surface interaction in the soil-slag-biological solids system
Authors: Trykoz L V , Panchenko S V , Bondarenko D O , Plugin A A , Borziak O S
Published: December 2019

The issue of wastes reclaiming in large cities is really a pressing problem today. First of all, the wastes which occupy wide areas of land need to be reclaimed. The metal production slag and waste water sediments are typical examples of such waste products. They create a wide area of ecological and social discomfort when collected and accumulated in large quantities after treatment. The purpose of this study is development of new soil materials which include waste products. The material properties can be influenced in a level of electric-surface interaction of the studied system components. The phase boundary presence and high degree of dispersion of the components require considering the sign of the charge of the particle surface and the particle size, influence of the charge on the nature of interaction between the surfaces and thus allows defining possible methods of modifying the surface properties in order to obtain materials needed. This includes modification of the surface of the aggregates and filling agents, activation of the functional groups, dispersed system stability, coagulation control, etc.
Concrete as a self-organizing system
Authors: Vyrovoy V M , Korobko O O , Sukhanov V G , Posternak O O
Published: December 2019

All levels of the product heterogeneities, including the product itself, are open complex systems, which are organizing themselves in autopoiesis mode. Such order of structure formation assumes a certain selectivity of the organization of the system while maintaining its openness to the influence of the environment. Factors of control may only initiate structural changes, but do not determine in what ways they will occur. The mechanisms of the structure organization at the selected levels of heterogeneities are qualitatively differing. Individual complex of processes and the phenomena is realized at each level; however, all heterogeneities are in the multi-scale co-ordination and influence each other, causing the interconnected structural variations. This supports the self-organization of the material structure. The mutual influence of the structural self-organization of individual levels of heterogeneities at the formation of the integral concrete structure is analyzed. Deformations determine the structure formation and functioning of concrete. Controlling the manifestation of deformation allows providing a directed structure of the material. For receiving the given sets of active elements, the factors controlling the processes of organization of micro- and macrostructures of concrete are accepted.
Dependence of Lamé transformation for concrete pipeline design calculation
Authors: Younis B , Saienko L
Published: December 2019

Determination of concrete strength and wall thickness for low pressure concrete pipe underground pipeline by possible way to identifications of the known dependencies by entering the correlation “wall diameter/wall thickness” and transformation of the Lamé formula. The conversion of the known dependencies, allowing to determine the normal hoop stress from the external equivalent load and internal pressure according to the Lamé dependence, allowed us to obtain new transformed dependencies for calculating the stresses in pipes under the combined action of internal pressure and external (reduced) load. Using the obtained equations allows you to determine the range of application of concrete (without metal reinforcement) pipes and select the concrete composition for the pipe production. It was determined in this study the stresses in the walls of concrete pipes under the combined action of an external (compressing pipe) load (the pipeline depth – the magnitude of the working fluid pressure) and internal pressure from the fluid transported under pressure.
Stress-strained state of steel-adhesive bonding on the acrylic adhesives
Authors: Zolotov S , Pustovoitova O , Firsov P , Kais Husain , Kamchatna S
Published: December 2019

Experimental results of determination of strength and deformation properties of acrylic glues of different compositions at short term, long term and cycle loading, as well as the character of their destruction are given in the article. Since acrylic adhesives are commonly used in construction activity, their physical-mechanical properties were determined, taking into account the type of action of the forces on them in the bonding of building constructions and elements. These forces include: compression, extension and shear. In the process of experiments in the composition of the acrylic adhesive the ratio of polymer, hardener and filler was taken into account.
The use of data by smart systems for price forecasting in the context of building customer relationships on the Lublin real estate market
Authors: Bojanowska A , Lipski J
Published: December 2019

This article aims to show how to design a functional application as an intelligent tool for forecasting real estate prices, among others, based on historical data. Real estate dealers or clients in this market are rarely aware of the possibility of using such a tool in the real estate valuation. This paper presents how the artificial neural network can be used for this purpose. The selected area of the Lublin real estate market has been covered by research carried out for this study. As input data for the smart system, historical data of transactions and variables characterising real estate were used, such as location of the property, its condition or size. Using the developed model, in the neural network, the sensitivity of the real estate price to selected features was carried out. It was also indicated how the use of this tool can facilitate purchasing decisions and customer relationship management on such a market.
Gas network improvement proposal using numerical simulation
Authors: Jurek T , Iwanek M
Published: December 2019

Simulation software packages are very useful tools for evaluating hydraulic conditions in gas systems, and therefore for supporting the design process, network maintenance and decisions about rerouting or modernisation of a network. In the range of this paper, a model of a real branched gas network covering 3 towns was created in the GAZNET software. At first, actual hydraulic conditions of gas flow in the pipes were simulated to evaluate distributions of flow velocity and pressure in the pipes. The obtained results indicated meaningful pressure drops and increase in flow velocity in some sections of the model, which not only constitutes a threat to provide required parameters of gas to consumers, but also forecloses connecting new consumers to the network. Thus, two variants of improvements were proposed: (1) expanding the network by building two additional sections or (2) increasing the number of gas sources by building additional pressure reduction and measuring unit. Conducted simulations indicated that changes of the network proposed in both variants clearly improve hydraulic conditions in the network model. However, the first variant was chosen as a better alternative, because distribution of hydraulic parameters in the model was more homogeneous than in the second variant, as well as because of economic considerations.
IT support for optimisation of abrasive water cutting process using the TOPSIS method
Authors: Radomska-Zalas A , Perec A , Fajdek-Bieda A
Published: December 2019

Modern production processes are becoming increasingly complex. At the same time, customers require high-quality products at the lowest price. This situation increases the importance of optimisation of production processes from the preparation of production to its implementation. Various methods of process optimisation have been devised to respond to the emerging phenomena including organisational aspects, device design, quality engineering and process automation. The TOPSIS method is used to make multi-criteria decisions. In this paper, a methodological study of this method was carried out, indicating conditions of applicability, assumptions and limitations, and the use of the TOPSIS method in the IT system supporting the optimisation of industrial processes on the example of waterjet cutting optimisation.
Numerical model for thermal calculation analysis of the wheel hub motor for electric car verified by laboratory tests
Authors: Bedkowski B , Dukalski P , Jarek T , Wolnik T
Published: December 2019

The article concerns the thermal analysis of an electric motor for mounting in a wheel hub of an electric car. The CFD model was calibrated on the basis of the results of laboratory tests of the prototype electric motor. The analysis was aimed at recognizing the possibility of increasing the load capacity of an electric motor through the use of dielectric materials with higher thermal conductivity than those used in the actual prototype. The authors presented the problem of heat removal from motors in wheel hubs, construction of the electric motor, the calculation model and analysis of calculation results.
Study of operating parameters of a plate conveyor used in the food industry
Authors: Caban J , Nieoczym A , Misztal W , Barta D
Published: December 2019

Internal transport (means of continuous transport) is an inseparable element of technological processes in the food industry. The selection of appropriate parameters of the transport equipment depends on the product being manufactured, its design features, packaging and transport conditions. The paper presents the characteristics of a plate conveyor, selection of operating parameters in the juice transport process in a glass bottle. The paper presents selected test results depending on the linear speed of the plate conveyor, the angle of inclination of the load mass transport module and the position of the gravity centre. The work defined the linear speed ranges of the conveyor and the angle of inclination of the conveyor transporting module for transported glass bottles filled with juice.
Analytical method for projecting the buckling form of composite palates with a cut-out
Authors: Falkowicz K , Szklarek K
Published: December 2019

The work focused on the original concept of a thin-walled plate element with a cutout, for use as a spring or a load-bearing element. The subject of the study were rectangular plates with a cut-out with variable geometrical parameters and with a variable angle of fibre arrangement, made of a carbon-epoxy composite with high strength properties in an asymmetrical lay-up, subjected to uniform compression. The paper presents a method of predicting the buckling form of composite plates with a cut-out ensuring the stable nature of the structure’s work. The influence of geometrical parameters of the cut-out and the angle of fibre arrangement on the value of the critical load of the structure and buckling form was investigated. The commercial ABAQUS programme using the finite element method was used to develop the discrete model and perform numerical calculations.
Numerical evaluation of friction effects on the energy absorption of square profiles under bending load
Authors: Estrada Q , Szwedowicz D , Vergara-Vazquez J , Rodriguez-Mendez A , Silva-Aceves J , Wiebe LC , Escarcega L
Published: December 2019

Friction is often associated with undesirable effects on mechanical systems. However, friction could be useful to increase the energy absorption capacity of thin-walled structures subjected to bending loads. The current article proposes the use of friction as an additional energy dissipating mechanism to plastic deformation. For this purpose, three different friction fixtures are presented and numerically evaluated using Abaqus/Explicit software. The friction fixtures were placed at the ends of square profiles generating internal, external and combined friction. In all cases, the square profiles were made of aluminium 6063-T5. The reliability of the numerical results was experimentally validated by a modified three-point bending test with friction. The numerical results for the three arrangements were compared with the results obtained for a profile without friction. According to our results, in all cases friction improves the energy absorption performance of the square profiles in a range from 48.71% to 179.19%. Finally, the best crashworthiness performance was obtained when external friction is generated at the ends of the tube. An increase in the crush force efficiency (CFE) parameter up to 71.47% respect to a typical profile was computed. Thus, the effectiveness of the friction mechanism was demonstrated.
Numerical analysis of the thin-walled structure with different trigger locations under axial load
Authors: Rogala M , Gajewski J , Ferdynus M
Published: December 2019

This paper presents the results of the numerical analysis of thin-walled structures with a square cross-section. Aluminium models contain different types of triggers and distance to the base. Postbuckling analyses were compared with the form of the buckle to find the most beneficial location of the trigger. The study problem was approachedwith FEM Abaqus.Numerical analysis results are shown in theLoad–Shortening diagram. The data obtained during numerical analysis were used to determine the crushing efficiency indicators such as SE, CLE, TE. The aim of the research was to obtain the best efficiency indicators for the tested positions of triggers.
Milling process diagnosis using computational intelligence methods
Authors: Żabiński T , Piecuch G , Żyła R , Prucnal S
Published: December 2019

The paper presents the results of research aimed at developing a method for hard-to-machine metal alloy milling process diagnosis using computational intelligence methods. To diagnose the process, a signal from an accelerometer mounted on the spindle of a CNC machine was used. The data were recorded during milling of Inconel 625 alloy workpieces, performed by sharp and blunt cutters. The acceleration signal metrics, both in the time and frequency domains were used to develop the classifiers. Based on the experiments, it has been demonstrated that it is possible to effectively diagnose Inconel alloy workpieces milling process using shallow computational intelligence methods (decision trees, k-NN and linear support vector machines). Python was used for data processing and visualisation as well as classifiers development and testing.
Study of buoyant force acting on different fluids moving over a horizontal plate due to forced convection
Authors: Singh J , Singh C
Published: December 2019

In this paper, the effect of buoyancy force on heat transfer over flat plate due to forced convection is investigated numerically. The governing equations namely continuity, Navier-stokes and energy equations were discretized by using an explicit finite difference technique. Code generation has been done in FORTRAN-95 programming language. The testing of FORTRAN code has been done for different fluids at different grid points. The length of horizontal flat plate (x) was taken as 0.5 m. The inlet velocity of fluid (u) at the edge of plate was taken as 3 m/s. The kinematic viscosity (υ) of air and water at 323 K were taken as 17×10-6 m2/s and 66×10-7 m2/s respectively. The surface temperature (Ts
) of plate and flow temperature (To) of fluid were taken as 300 K and 323 K respectively. The grid was discretized by continuous method into 1001×101 (m×n) mesh points. The results show the boundary layer thickness, velocity and temperature evolutions, and heat transfer coefficient formed by different fluids. Also, the heat transfer coefficient to surrounding fluid across flat plate was found higher for air as compared to water. Results showed that buoyancy force acts from downward position so it was observed maximum at lower distance of plate. However, buoyancy effect reduces as the distance of x increases.
Selection of the optimal unit of analysis in assessing the structure of terrestrial arthropods assemblages
Authors: Kirichenko-Babko M , Danko Y , Majerek D
Published: December 2019

The article shows the use of statistical methods of multivariate analysis on the example of environmental data – the species composition of terrestrial arthropods. It is shown that the research results largely depend on the scale of observations made – whether it is a study conducted in a whole ecosystem or in a separate landscape element, type of habitat or, finally, an analysis of elementary samples. The results and their interpretations directly depend on the scale chosen by the researcher. We were mainly concerned with the reliability of using of multidimensional statistics in practical situations.
Synthesis of anisotropic Au–Cu alloy nanostructures and its application in SERS for detection of methylene blue
Authors: Singh Manish Kumar , Chettri Prajwal , Basu Joysurya , Tripathi Ajay , Mukherjee Bratindranath , Tiwari Archana , Mandal R K
Published: December 2019

Au–Cu alloy nanostructures have been synthesized in aqueous phase through co-reduction of HAuCl4.3H2O and CuCl2.2H2O by glucose in presence of hexadecylamine at ∼80 °C. By changing the synthesis conditions, nanostructures of various shapes such as nanowires, multiply twinned tripod, tetrapod, etc were observed. Systematic variation of the synthesis condition not only leads to change in size and particle morphology but also develops various other crystallographic characters in the nanoparticles. Alloying behavior of Au–Cu has been examined through transmission electron microscope operating in its conventional and analytical modes coupled with high resolution phase contrast microscopy. These results suggested that nanostructures are composed of homogeneous Au–Cu alloy. Preferential attachment along {111} and {100} crystallographic facets of Au–Cu alloy nanoparticles led to the formation of nanowires. Multiply twinned branched shape Au–Cu (width of branch ∼30 nm) nanostructures exhibit localized surface plasmon resonance maxima in the near-infrared region. The branched shape Au–Cu alloy nanostructures display better surface enhanced Raman scattering response in the detection of methylene blue as compared to spherical Au nanoparticles.
Photocatalytic degradation of methylene blue under visible light by dye sensitized titania
Authors: Samuel Joshua J , Yam F K
Published: December 2019

The use of textile dyes remain relevant in the issue of water pollution. With the potential harm it may possess on the local flora and fauna, various methods of dye removal have been researched and employed, including photocatalytic degradation. TiO2, being a suitable semiconductor for this purpose needs to be sensitized prior to use, either by doping or chemical adsorption in order to activate in visible light. In this study, various natural dyes were employed to sensitize TiO2. It was found that chlorophyll was superior in dye degradation, with about a 60% reduction in dye concentration over a target 2 h, greater than that of the synthetic sensitizer N-719. This places chlorophyll based photocatalytic reactors as a potential tool for organic pollutant degradation which are also easy to manufacture and abundant in nature.
Rates of ecomorphological trait evolution in passerine bird clades are independent of age
Authors: Phillips Anna G , Töpfer Till , Böhning-Gaese Katrin , Fritz Susanne A
Published: December 2019

Although the links between species richness and diversification rates with clade age have been studied extensively, few studies have investigated the relationship between the rates of trait evolution and clade age. The rate of morphological trait evolution has repeatedly been shown to vary through time, as expected, for example, for adaptive radiations, but the strength and sources of this variation are not well understood. We compare the relationship between the rates of trait evolution and clade age across eight monophyletic clades of passerine birds by investigating ecomorphological traits, i.e. morphological traits that influence the ecology of the species directly. We study the ecomorphological divergence pattern using analyses of the disparity through time and determine the best-fitting model of evolution for each trait in each clade. We find no support for a consistent dependence of evolutionary rates on clade age across wing, tail, tarsus and beak shape in our eight clades and also show that early burst models of trait evolution are rarely the best-fitting models within these clades. These results suggest that key innovations or adaptive radiations might be less common evolutionary patterns and processes than generally thought or might depend on the taxonomic level investigated.
Dispersal, endosymbiont abundance and fitness-related consequences of inbreeding and outbreeding in a social beetle
Authors: Tremmel Martin , Steinitz Hadas , Kliot Adi , Harari Ally , Lubin Yael
Published: December 2019

Most social species outbreed. However, some have persistent inbreeding with occasional outbreeding, and the decision of the individual regarding whether to stay in the natal group and inbreed or to disperse, with the potential to outbreed, is flexible and may depend on social, genetic and ecological benefits and costs. Few of these factors have been investigated experimentally in these systems. The beetle Coccotrypes dactyliperda Fabricius, 1801 (Scolytidae: Xyloborinae) lives in extended family colonies inside date seeds. The beetles inbreed, but some individuals disperse away from the natal seed and may outbreed. We investigated dispersal behaviour and assessed fitness-related measures in inbred and outbred offspring, in addition to the relative abundance of two endosymbionts. We predicted inbred offspring to have higher fitness-related measures and a reduced tendency to disperse than outbred offspring, owing to fitness benefits of cooperation within the colony, whereas increased endosymbiont abundance will promote dispersal of their hosts, thus enhancing their own spread in the population. Dispersing beetles were more active than ones that remained in the natal seed. As predicted, fewer inbred offspring dispersed than outbred offspring, but they matured and dispersed earlier. Fitness-related measures of inbred mothers were either lower (number of offspring) or not different (body mass) from those of outbred mothers. Inbred dispersers had greater amounts of Wolbachia, suggesting a role in dispersal. The results support the hypothesis that inbred females reduce dispersal and that early maturation and dispersal are likely to be benefits of increased cooperation in brood care.
Simultaneous monitoring for regression coefficients and baseline hazard profile in Cox modeling of time-to-event data
Authors: Xue Yishu , Yan Jun , Schifano Elizabeth D
Published: December 2019

The Cox model is the most popular tool for analyzing time-to-event data. The nonparametric baseline hazard function can be as important as the regression coefficients in practice, especially when prediction is needed. In the context of stochastic process control, we propose a simultaneous monitoring method that combines a multivariate control chart for the regression coefficients and a profile control chart for the cumulative baseline hazard function that allows for data blocks of possibly different censoring rates and sample sizes. The method can detect changes in either the parametric or the nonparametric part of the Cox model. In simulation studies, the proposed method maintains its size and has substantial power in detecting changes in either part of the Cox model. An application in lymphoma survival analysis in which patients were enrolled by 2-month intervals in the Surveillance, Epidemiology, and End Results program identifies data blocks with structural model changes.
Sweet dreams: therapeutic insights, targeting imaging and physiologic evidence linking sleep, melatonin and diabetic nephropathy
Authors: Afsar Baris , Elsurer Afsar Rengin , Sag Alan A , Kanbay Asiye , Korkmaz Hakan , Cipolla-Neto José , Covic Adrian , Ortiz Alberto , Kanbay Mehmet
Published: December 2019

Melatonin is the main biochronologic molecular mediator of circadian rhythm and sleep. It is also a powerful antioxidant and has roles in other physiologic pathways. Melatonin deficiency is associated with metabolic derangements including glucose and cholesterol dysregulation, hypertension, disordered sleep and even cancer, likely due to altered immunity. Diabetic nephropathy (DN) is a key microvascular complication of both type 1 and 2 diabetes. DN is the end result of a complex combination of metabolic, haemodynamic, oxidative and inflammatory factors. Interestingly, these same factors have been linked to melatonin deficiency. This report will collate in a clinician-oriented fashion the mechanistic link between melatonin deficiency and factors contributing to DN.