bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Study on Effect of Steel Tube in Axial Behavior of CFST Stubs
Authors: Jayaprakash Narayana S. , Manvi Rao Kolan 
Published: December 2020

Abstract
Concrete filled steel tubular (CFST) columns are becoming popular due to its advantages from both steel and concrete in resisting loads. CFST members are made up of steel hollow section of rectangular or circular sections filled with plain or reinforced concrete. CFST columns can be used effectively in high raised structures and in bridges. The reduced cross sections of columns can be achieved by the composite action of steel and concrete. The steel tube provides confinement to the concrete and helps to improve load carrying capacity. The concrete core offers higher resistance to axial compression. The inward buckling of steel tube will be avoided due to concrete and the out buckling resistance may be improved due to higher stiffness of the column due to higher gross moment inertia with combined effect of steel and concrete. This experimental work made an attempt to understand the effect of thickness of steel tube in behavior of CFST stubs.
In the present experimental study, a total of 24 cylindrical concrete filled steel tube specimens were prepared to evaluate the uniaxial compressive behavior and to understand the effect of thickness and aspect ratio (h/D) on the compressive strength. Two different thickness of steel tubes 3 mm and 5 mm and four aspect ratios (h/D) 1, 2, 3 and 4 are considered in the present study. M30 grade of concrete is used. From this study, as the aspect ratio increases the buckling loads decreases. The decrement is up to 37% in aspect ratio 4 when compared to aspect ratio1.
Influence of Waste Brick Powder on Properties of Masonry Mortar and its Impact on the Masonry Strength
Authors: Murthi P , Poongodi K , Kottiswaran N 
Published: December 2020

Abstract
The rapid urban development leads the exponential growth of construction and demolition waste in India. The handling and disposal strategies of building debris are not properly developed and create more threats to environment. Brick and concrete materials are the main wastes generated during demolition. As an alternate measures of recycling the brick waste, it is proposed reusing the waste brick powder particles in to the development of masonry mortar. The waste brick powder is used as cement replacement material and four different level of replacement was considered in this investigation as 5%, 10%, 15% and 20%. The strength of masonry mortar with three ratios (1:4, 1:6 and 1:8)at 7 days, 28 days and 90 days were determined. Further, the impact of innovative masonry mortar on masonry prism strength and bond strength were determined. The results obtained from this investigation had concluded that the cement can be replaced 12% to 15% by brick powder without affecting the compressive strength and shear bond strength performance of brick masonry.
An Experimental Investigation on Concrete by Partial Replacement of Cement by Fly Ash and Fine Aggregate by Quarry Dust
Authors: Damodhara Reddy B , Aruna Jyothy S , Kiran Kumar N , Hemanth kumar K 
Published: December 2020

Abstract
The concrete is a composite construction material. The necessary ingredients like cement, Natural Sand, Gravel and potable Water are important components of concrete. The issue of environmental degradation and expensive nature of the river sand makes us to switch on to the alternative sources. One such material having strength and durability is quarry dust which is a by-product from quarries which is causing lot of environmental issues. In this present study the replacement of the fine aggregate is done with quarry dust and cement with fly ash. Replacements of cement are partially done with Fly Ash at 0%, 5%, 10%, 15%, 20% and 25%. The experimental work primarily concentrates with compressive strength, split tensile strength and sturdiness properties of M40 grade of concrete at completely different ages i.e., 7 days, 28 days, 56 days and 90 days. The Split tensile strength and sturdiness checks like Acid attack and Chloride penetration test for 28 day were done. The Test results were promising when cement was partially replaced by 10% of Fly ash for all the days.
Zinc in the body and somatic health of industrial workers
Authors: Slepchenko G , Moiseeva E , Khlusov I 
Published: December 2020

Abstract
30% of industrial workers have a chronic (at least 3-4 months) zinc deficiency as a vital trace element necessary for the functioning of a significant amount of metalloproteins. The cause of zinc deficiency may be copper intoxication noted earlier, which together is important for the development of structural pathology of internal organs.
Ecologically safe device technologies of road covering with the using technogenic materials
Authors: Potapova S O , Shepelev I I , Eskova E N , Bochkov N N , Nemerov A M 
Published: December 2020

Abstract
The influence of nepheline sludge on the soil of a roadside strip when used in the device of road coverings is studied. Chemical analysis of soil samples taken from the roadside strip of a highway constructed using a base made of nepheline sludge was performed. It is shown that the change in the content of calcium-the main element of the sludge at a distance from 5 to 100 m from the road did not exceed its value in the background sample, and the content of exchangeable aluminum in the soil of the analyzed areas was at a very low level-less than 0.5 mg/kg and practically did not affect its content in the soil at all sampling points from 0 to 150 m from the road. Based on the conducted ecotoxicity studies using single-and dicotyledonous plants, the possibility of using nepheline sludge as a component of road covering in the form of a nepheline-crushed stone mixture has been established and the absence of toxicity in the analyzed soil samples at various distances from the roadside strip has been proved.
Research of the process of vegetable oil extracting under the influence of a high frequency wave field
Authors: Yu Ovsyannikov V , Berestovoy A A , Lobacheva N N , Toroptsev V V , Trunov S A 
Published: December 2020

Abstract
Research in a laboratory press equipped with an ultrasonic vibrator was performed to study the nature of a high frequency wave field influence on the process of vegetable oil extracting from safflower seeds. The initial moisture content of safflower seeds, the rotational speed of the press screw, the frequency and amplitude of ultrasonic vibrations have the greatest influence on the oil yield and the cake residual oil content. The analysis of the dependences obtained showed that the parameters of the safflower seed pressing process, the values of which could be varied during the experiments, affect the oil yield identically, namely, with an increase in the rotational speed of the press screw, the oil yield decreases and, consequently, the cake oil content increases. It was found out that moisture content raising increases the oil yield and reduces the residual oil content. Moreover, the most rational value of moisture content in terms of absolutely dry matter is 8.7…11.2%. It was revealed that an increase in the pressure given to the product in the press occurs with a decrease in the effective viscosity inside the surface layer of the mass being pressed due to ultrasonic vibrations imposition. The following parameters should be focused on as rational parameters for safflower seeds pressing providing the minimum residual oil content in the cake: the ultrasonic waves frequency is 22…28 kHz, the amplitude is more than 40 • 10−3 m and the pressure value in the press is from 12…13 MPa. These values obviously depend directly on the grain behavior and its movement in the press during exposure to high-frequency ultrasonic vibrations.
Mathematical model of wedge-shaped sliding support with low melting metal coated guide for partially filled working gap
Authors: Mukutadze M A , Opatskikh A N , Morozova A V , Zadorozhnaya N S 
Published: December 2020

Abstract
The reported study presents an asymptotic series solution to a system of differential equations in powers of a small parameter K depending on melting and a mechanical energy dissipation rate. Further, a self-similar solution has been found, as a consequence, a profile of velocities, pressure, principal operational characteristics, load capability, and friction force have been determined for a partially grease-filled working gap.
Tribological tests of frictional carbon/carbon composite in braking mode
Authors: Alisin V V 
Published: December 2020

Abstract
The article discusses the issues of friction and wear testing of a carbon-carbon composite of tribological purpose. The experiments were performed on a bench, the work of which is based on the absorption of kinetic energy of rotating masses with materials intended for use in brake devices. The friction coefficient and wear rate of the friction carbon composite in braking mode are investigated. Ring samples are divided into 6 sectors, in each of which, after testing, the parameters of the roughness of the friction surfaces and wear during one braking are determined. The value of linear wear was determined as the average value over 6 sectors for rotating and stationary samples. Changes in the structure of friction surfaces are investigated. Metrological support of the experiments was carried out by statistical processing of the results. The errors in measuring the coefficient of friction and wear rate are determined. High resistance to energy absorption and thermal shock of the studied frictional material is established, which open up the prospects for the mass use of C/C in transport brake devices.
Assessment of the technical and technological condition of the transport complex
Authors: Gubin A V , Pavlova A V , Kosolapov Yu V , Morkovkin D E , Lineva E S , Gibadullin A A 
Published: December 2020

Abstract
The presented study is devoted to the assessment of the technical and technological state of the transport complex. The work analyzed indicators reflecting the share of fixed assets of the transport complex as part of national fixed assets and the degree of depreciation of production capacities of the transport industry. The analyzed indicators reflect that about a quarter of all fixed assets are related to the transport complex, and the volume of depreciated fixed assets exceeds 50%, while production capacities are updated to increase fixed assets, and not to ensure a qualitative or quantitative upgrade. The study proposed a model for ensuring the qualitative development of the transport complex, which contains measures to update existing fixed assets and new principles for the management and development of the transport complex.
Evaluation of friction behaviour on human finger skin considering precision grip task
Authors: Cârlescu V , Oprişan C M , Ianuş G , Olaru D N 
Published: December 2020

Abstract
Human hands perform daily different tasks and the fingers skin comes in contact with many surfaces and objects. Grip task of objects can be performed by using different combination of the fingers. Precision grip task is influenced by several factors which decide the grip force of the individuals performing the task. This study aims to evaluate in vivo the coefficient of friction (COF) between a steel cylinder and the skin of fingers’ phalanges from both hands for three healthy subjects. The experiments were realized in a reciprocating-sliding contact with normal loads of 1 N and 2 N and sliding speed of 1 mm/s. Also, indentation tests were realized in order to determine the skin deformation of the fingers phalanges under normal loads. The indentation results show that distal phalanges (fingertip) play a significant role in deciding the grip force. The friction tests reveal that the coefficient of friction varies between 0.3 and 1.1 along the fingers phalanges according to the age, gender and skin structure of the test subjects. The distal phalanges of index and middle fingers showed the highest value of the coefficient of friction in the case of the subjects that mainly use the right hand. These aspects can be considered in developing devices for grip and sensing tasks applications.
SR EN ISO 20623 - A standard for tribological evaluation of lubricants that may bust innovation
Authors: Deleanu L , Georgescu C , Ionescu T F , Guglea D , Isacescu D 
Published: December 2020

Abstract
This paper presents the opportunities offered for research by using the four ball machine and the procedures included in SR ISO 20623:2018. There are presented results of research studies that are started from the procedures and parameters included in standard, but also wear and friction parameters that derived from recording friction and wear scar dimensions and texture parameters.
Experimental assessment of permeability variation with the compression of soft reticulated foams
Authors: Enescu C. , Turtoi P. , Cicone T. , Istrate C.V. 
Published: December 2020

Abstract
The resistance to flow of imbibed fluids in soft porous structures subjected to compression can be a solution for impact attenuation. The mechanism, named ex-poro-hydrodynamic (XPHD) lubrication, is based on permeability variation with porosity, which, at its turn, depends on the compression degree of the porous structure. A literature survey revealed scarce information regarding the permeability of compressed reticulated foams or 3D fiber-based structures, used in XPHD applications. Moreover, the permeability depends on the fluid and its velocity. This paper presents experimental data of the permeability of glycerine for an in-plane, axisymmetric flow through a porous material subjected to various degrees of compression. The experiments were done on an in-house made radial permeameter with pressure differentials up to 6 bars. The experimental data was compared with the predicted results, using the well-known Kozeny-Carman equation and related formulations.
Light_Sport_Aircraft, wing design elements and resistance calculus for a new 3D model applied for flaps control
Authors: Ghiţescu I-M , Ghiţescu M , Borza P N , Stroe I 
Published: December 2020

Abstract

The aim of the paper is analyze of a new linkages used in Light_Sport_Aircraft control, flaps control, on bases of the aerodynamics, structural modelling of linkages with Multibody System method (MBS) and resistance calculus of wing. In virtual prototyping of the aircraft, these linkages have to be modelled by a minimum number of bodies (MBS min). In this paper is described one concrete mechanical flaps control. This will be the bases for virtual modelling and prototyping of these subsystems as parts of the whole product (airplane).
Simulation of high-pressure pump behaviour after running in urban regime
Authors: Iordache R C , Bujoreanu C , Petrea N D , Ianuş G 
Published: December 2020

Abstract
The wear of the high-pressure pump is directly proportional with the engine operating mode of the vehicle. Due to the urban areas congestion, the engine assembly components can be affected and they can lose their reliability. The engine operation can be described as a cyclical model, reaching all the operating points: idle, cranking, maximum torque and maximum power. Thus, the discontinuous operation (proportional with car engine cycles) of the high pressure pump can create different types of wear for its components. Our paper presents an experimental test that simulates the behaviour of the pump after the operation of the vehicle in urban regime with a cyclical type in a course of 10.000 km. It aims to achieve the most important engine operating points. In order to do this, an electronic control unit is installed on the test machine, which has the role of controlling the electronic pump valve. All data (pressure, speed, temperature) are recorded in real time and stored in the memory unit of the test machine. The obtained data are analyzed and the pump is disassembled. Wear is observed on the main components (roller, shoe and driveshaft), but this does not lead to pump malfunction. After this analysis, the main components of the tested pump are compared with new components in order to evaluate the wear level.
Experimental investigation of the limits of fluid squeeze out from an imbibed porous material
Authors: Turtoi P , Lupu G , Cicone T , Apostol D 
Published: December 2020

AbstractThe resistance to flow of a liquid squeezed out of a soft, porous structure subjected to compression generates a high load capacity and represents the mechanism on which the XPHD lubrication is based. The process is dependent on permeability which, in turn, depends on porosity, variable during compression. This study investigates experimentally the effect of compression on the porosity of open-cell polyurethane foams. An experimental device is used to compress a disc made of a porous material imbibed with glycerine and the volume of the remaining fluid is measured. Two reticulated foams with the same internal structure but with different initial porosities were selected for the study. The results are consistent and show a good correlation when compared with theoretical predictions. It is shown that the deformation of the solid fraction closes pores before squeezing out all the fluid. A residual porosity and a threshold strain when the pores are closed are put in evidence.
The dimensional accuracy of plastic parts made by the fused filament fabrication
Authors: Boca M A , Sover A , Slătineanu L 
Published: December 2020

Abstract
Fused filament fabrication (FFF) process has gained considerable public interest in the last years and due to its numerous advantages, a study that identifies and explains the influence of used plastic materials on the accuracy of the parts achieved by FFF could be considered as necessary. The present study contains a brief introduction in the additive manufacturing basic notions, technologies, and equipments. In a similarly manner the 3D scanning process is also synthetically presented. The main focus is on studying the accuracy of test parts obtained in laboratory conditions using the most used 5 polymer materials (PLA, ABS, PP, PA and PET). The experiments were conducted using software and equipment dedicated to 3D printing for FFF-technology and optical scanning. Results sustained by graphs, tables and images showed that the ABS type material provided the best results concerning the linear dimensional accuracy along the X and Y axes. For the circular and linear dimensions accuracy along the Z-axis, the lowest deviations in comparison with the nominal dimensions were found in the case of the test part made of PLA. The experiments also proved that the materials that had a higher proportion of the studied points included in the tolerance zone were the PLA and the PET.
A hands-on approach to demonstrating active noise cancelling
Authors: Coandă P , Avram M , Comeagă D 
Published: December 2020

Abstract
As noise pollution has become an increasingly major factor in the quality of urban life, noise cancelling methods started to be a relevant option for everyday life. Starting from the first active noise cancelling headphones build for aircraft industry in order to facilitate communication between pilots, in the last decade, active noise cancelling products have become more and more relevant. Factories, military and lately, civil usage of active noise cancelling technology transformed this industry and made it widely available. The purpose of this paper is to demonstrate a practical way of active noise cancelling using LabVIEW. Two sound waves are guided through a cylindrical conduit and at a given position, by modifying the phase and amplitudes between the two signals, an amplitude close to zero is expected.
Bearing fault diagnosis using the Kolmogorov-Smirnov test on frequency features extracted using the Goertzel algorithm
Authors: Cordoneanu Daniel 
Published: December 2020

Abstract
Fault diagnosis has been a field of interest during the last period, especially for predictive maintenance, given the advances in artificial intelligence and the available state of the art algorithms for machine learning, in a great number of libraries. In the industrial sector, fault diagnosis plays a very important role in order to avoid as much as possible downtime. Usually, rotating motors are involved in the actuation of the machines used in industry; therefore, bearings are an important part of the kinematic chain. The faults of the defective bearings can be detected within the frequency spectrum, at particular frequencies, which can be mathematically computed on the geometrical bases. Moreover, the use of the Goertzel algorithm allows the extraction of the specific features for these frequencies and their harmonics. The paper proposes a new approach of these features use for creating an initial data distribution, in order to be compared with future acquired data by use of the Kolmogorov-Smirnov test, as a good-fitness test for the new data.
Torsion frequency response function of a train driving wheelset
Authors: Gheţi M A , Mazilu T 
Published: December 2020

Abstract
The driven wheelset is used in traction rail vehicles (locomotives, electric trains, trams, etc.) to support part of the weight of the vehicle and to drive and brake the vehicle. The wheelset consists of the axle on which two wheels and the drive gear are mounted. The torsion vibrations of the driven wheelset may be induced by the variation of the adhesion force at the level of the contact between the wheels and the track but may also result from electromechanical interactions between the electric traction motor and the motor axle. In this paper, a mechanical model of the driven wheelset consisting of a circular shaft free at both ends and three rigid discs representing the two wheels and the drive gear is considered. The modal analysis method is used to solve vibrational motion equations in steady state harmonic behavior. The frequency response function of the system and the impact of the positioning of the drive gear on the wheelset shall be highlighted. For the verification of the proposed mechanical model, the numerical results are compared with the results obtained by experimental determinations carried out on a laboratory stand.
Hydraulic pitch control including virtual instruments
Authors: Pelin R I , Tiţa I 
Published: December 2020

Abstract
The main objective of this research work is to analyse and develop elements of a controller for hydraulic system used for pitch control of a horizontal axis wind turbine. Simulation of a hydraulic system is necessary in order to discover weak points before starting the design of the system. Some elements of the system may remain virtual elements and instruments as LabVIEW offers the possibility. These elements may be analysed and developed before the experimental model is realised and finally used, as they are, as a part of the experimental equipment. For some purposes it is possible to develop specific elements using the built-in blocks.
A comparative analysis between some dynamic models for the vehicle suspension system
Authors: Alexandru C 
Published: December 2020

Abstract
This article deals a comparative analysis between several representative dynamic models for the suspension system of the motor vehicles, namely quarter-vehicle, half-vehicle and full-vehicle models. The dynamic model of the suspension system contains the guiding linkages of the front and rear wheels/axle, by case, along with the elastic and dissipative suspension elements (helical springs, shock absorbers/dampers, buffers limiting the expansion & compression suspension travel, bushings, tires). The dynamic analysis (simulation) of the considered models was carried out with the help of virtual prototyping software solution ADAMS (currently developed by MSC Software Corporation), by considering the dynamic with shock regime, which consists in the sudden release of the car to fall on the ground from a given height. This is one of the standard tests in automotive industry for evaluating the comfort performance of the vehicles.