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1 – 10 of 335Examines the thirteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched…
Abstract
Examines the thirteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.
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O.S. Aleksic, S.M. Savic, M.V. Nikolic, L. Sibinoski and Lukovic
The purpose of this paper is to apply negative thermal coefficient (NTC) thick film segmented thermistors (TFSTs) in a micro‐flow sensor for water.
Abstract
Purpose
The purpose of this paper is to apply negative thermal coefficient (NTC) thick film segmented thermistors (TFSTs) in a micro‐flow sensor for water.
Design/methodology/approach
A TFST is printed using NTC paste based on nickel manganite. The resistance of this thermistor is measured in a climatic chamber and the resulting curves are calibrated. A micro‐flow sensor is designed using a self‐heated segmented thermistor. The sensing principle is based on heat loss depending on the water flow intensity through the capillary. Water flow calibration is performed. The sensor sensitivity, inertia, and stability are analyzed.
Findings
The micro‐flow sensor exhibits good stability, suitable sensitivity, and inertia for integral measurements of water flow.
Practical implications
Advantages of a micro‐flow sensor using a TFST include low energy consumption, simple measuring procedure, and passive electronics.
Originality/value
This paper describes initial work on a micro‐flow sensor for water using TFSTs.
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Nada Ratković, Vukic Lazić, Dušan Arsić, Ružica R. Nikolić, Radica Prokić Cvetković and Olivera Popović
The purpose of this paper is to point out the possibilities for friction welding of dissimilar steels which are used in various industries. In addition, friction welding…
Abstract
Purpose
The purpose of this paper is to point out the possibilities for friction welding of dissimilar steels which are used in various industries. In addition, friction welding is a welding method that is applied for executing the very responsible joints. This research is focused on friction and tribological processes in the friction plane of the two pieces during the welding.
Design/methodology/approach
The present study research has been conducted based on the experimental testing of cylindrical specimens and results are analyzed.
Findings
The austenite grain size is affected by several factors through the friction process phase and the compacting phase during the welding. The very fine grain is the consequence of the high degree of the plastic deformation of the near-the-contact layers even in the friction phase. The viscous layer, which is formed during the stable friction phase, is the area where the moving of matter occurs according to a very complex mechanism.
Originality/value
The paper contains useful results from the area of conventional friction welding of dissimilar steels and it can be very useful to researchers and engineers who deal with similar problems.
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Nikolic´, Lj.M. Simovic and T.V. Mihailovic
In this paper, values of deformation components (elastic, viscoelastic, plastic) of clothing wool fabrics by measuring the crease recovery angle in various directions to…
Abstract
In this paper, values of deformation components (elastic, viscoelastic, plastic) of clothing wool fabrics by measuring the crease recovery angle in various directions to the warp direction (0°‐warp, 30°, 45°, 60°, and 90°‐weft) were determined. The size as well as the change of deformation component from warp to weft direction was presented through polar diagrams. On the basis of the results of investigation it is possible to conclude that all investigated fabrics (plain, 2/2 twill, cross twill), regardless of the biaxiality concerning quickly reversible (elastic) deformation, tend toward isotropy in total reversible deformation (elastic + viscoelastic). Concerning the plastic deformation value, mentioned investigated fabrics also express tendency toward isotropy.
Raghavendra Rao N.S. and Chitra A.
The purpose of this study is to extend a sensitivity-based reliability technique for the processors deployed in industrial drive (ID).
Abstract
Purpose
The purpose of this study is to extend a sensitivity-based reliability technique for the processors deployed in industrial drive (ID).
Design/methodology/approach
The processor provides flexible operation, re-configurability, and adaptable compatibility in industrial motor drive system. A sensitivity-based model allows a robust tool for validating the system design. Sensitivity is the probability of a partial failure rate for a distributed variable; sensitivity and failure rates are also complementary. Conversely, traditional power electronic components reliability estimating standards have overlooked it, and it is essential to update them to account for the sensitivity parameter. A new sensitivity-based reliability prediction methodology for a typical 32-bit microprocessor operating at 30ºC deployed in ID is presented to fill this gap. The proposed techniques are compared with the estimated processor reliability values obtained from various reliability standards using the validated advanced logistics development tool. The main contribution of this work is to provide a sensitivity extended reliability method over the conventional method directing toward improving reliability, availability, and maintainability in the design of ID.
Findings
The analysis shows that the sensitivity of the processor’s circuit increases due to increases in complexity of the system by reducing the overall mean time between failure upon comparing among conventional reliability standards.
Originality/value
The significance of this paper lies in the overall, sensitivity-based reliability technique for processors in comparison to the traditional reliability complexity in IDs.
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Milan Djordjević, Vesna Mandić, Srbislav Aleksandrović, Vukić Lazić, Dušan Arsić, Ružica R. Nikolić and Zvonko Gulišija
The purpose of this paper is comparison of experimental values of the drawing forces to numerical values in different contact conditions, taking into account the…
Abstract
Purpose
The purpose of this paper is comparison of experimental values of the drawing forces to numerical values in different contact conditions, taking into account the appearance of galling which occurs due to of difficult drawing process conditions.
Design/methodology/approach
The following two research approaches are used in this paper – the physical modeling, realized by the laboratory experiment, and the numerical simulation of the ironing drawing process. By analyzing the obtained results, the technique of physical modeling, with help of the laboratory equipment and numerical simulation by application of the finite element method, can be successfully used in studying the thin sheet ironing – strip drawing process.
Findings
It is significant to compare values of the deformation forces obtained by physical experiment to values obtained by the numerical simulation. In that way, it is possible to compare applied contact conditions (four lubricants in that case) and estimate matching of experimentally and numerically obtained results of the deformation forces. Presented results point out very good technological characteristics of ecologically friendly lubricant (single-bath) and grease based on MoS2. Significant decrease of the deformation force was achieved by its application, as well as maintaining of the lubricant’s layer during the forming process and almost complete elimination of galling on the contact.
Practical implications
Numerical analysis of stresses in the working piece wall, during the thin sheet strip drawing, requires precise values of the friction coefficient. It is an important indicator because one can define the contact conditions as the input data for the numerical simulation, based on its values for each type of lubricants and each value of the compressive lateral force.
Originality/value
The environmentally friendly lubricant tested exhibits a more favorable distribution of the drawing force during the process, mainly in experimental case. Grease based on MoS2 has good lubricating properties but that lubricant is conventional and environmentally unacceptable. Ecologically friendly lubricant can be successfully used in real ironing strip drawing process especially for high values of holding force achieving an increased tool life.
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Milos Milovancevic, Vlastimir Nikolic, Nenad T. Pavlovic, Aleksandar Veg and Sanjin Troha
The purpose of this study is to establish a vibration prediction of pellet mills power transmission by artificial neural network. Vibration monitoring is an important task…
Abstract
Purpose
The purpose of this study is to establish a vibration prediction of pellet mills power transmission by artificial neural network. Vibration monitoring is an important task for any system to ensure safe operations. Improvement of control strategies is crucial for the vibration monitoring.
Design/methodology/approach
As predictive control is one of the options for the vibration monitoring in this paper, the predictive model for vibration monitoring was created.
Findings
Although the achieved prediction results were acceptable, there is need for more work to apply and test these results in real environment.
Originality/value
Artificial neural network (ANN) was implemented as the predictive model while extreme learning machine (ELM) and back propagation (BP) learning schemes were used as training algorithms for the ANN. BP learning algorithm minimizes the error function by using the gradient descent method. ELM training algorithm is based on selecting of the input weights randomly of the ANN network and the output weight of the network are determined analytically.
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Eswara Krishna Mussada and P.K. Patowari
The current research work presents the application of fuzzy logic modeling for electric discharge coating (EDC) process for predicting the material transfer rate (MTR)…
Abstract
Purpose
The current research work presents the application of fuzzy logic modeling for electric discharge coating (EDC) process for predicting the material transfer rate (MTR), which has the capability of producing thick and thin films on the conductive substrate material.
Design/methodology/approach
Thirty-two real-time experiments were conducted, and fuzzy rules were framed from the inference made from this experimental data. Validating experiments were carried out to check the feasibility of the developed model in prediction.
Findings
A fair agreement has been observed between experimental results and the outcomes of fuzzy model. This was supported by a goodness of fit value of 0.917. The values of adjusted R2 and standard error were 0.914 and 19.112, respectively.
Research limitations/implications
Current research deals with the prediction of MTR at various parameter grouping conditions, which majorly influence the response parameters. However, other parameters such as quality of the dielectric fluid, flushing pressure and purity of the electrode and work material and so on that influence the response parameters could be further investigated and stand as a future scope of the current work.
Practical implications
MTR is a response parameter that accounts the actual material transfer to the workpiece during the deposition process. This parameter supports/alters the hardness, adhesion, wear resistance and other mechanical properties of the work material. The current modeling work helps to take an optimum decision without conducting large number of experiments at the industrial scale. Due to the nature of fuzzy logic, this method has a potential advantage in dealing with real-time data for various industrial applications.
Originality/value
Developing a fuzzy model for EDC process is not yet addressed, and to attain the economic objective of the process, optimal deposition conditions must be determined, which help the industries to reduce the operation costs. The current study outcomes substantiate the effectiveness of the fuzzy logic in decision-making and prediction of response parameters.
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Mohd Aaqib Sheikh, Charanjiv Singh Saini and Harish Kumar Sharma
The study was aimed to explore the potential impact of microwave heating (450 W for 2, 4, 6 and 8 min) on antioxidant activity, anti-nutritional factors, volatile and…
Abstract
Purpose
The study was aimed to explore the potential impact of microwave heating (450 W for 2, 4, 6 and 8 min) on antioxidant activity, anti-nutritional factors, volatile and phenolic compounds of the plum kernels.
Design/methodology/approach
Plum kernels are rich in proteins, lipids and bioactive compounds that are mostly underused and undervalued.
Findings
The results showed that microwave heating at 450 W for 6 min significantly (p < 0.05) increased the antioxidant activity, total phenolic and flavonoid content, while the longer treatment time (450 W for 8 min) adversely affected the phenolic compounds. Most importantly, the anti-nutritional factors like amygdalin, hydrocyanic acid, phytic acid and tannin content were reduced up to 87.1, 84.7, 20.9 and 46.2%, respectively at 450 W for 6 min treatment conditions, which was confirmed from the larger shifts observed in FT-IR spectra near 1,157 cm−1. Microwave heating at 450 W for 6 min also proved beneficial in improving the bioavailability of volatile and phenolic compounds including chlorogenic acid, gallic acid, syringic acid, (+)-catechin, caffeic acid, ß-carotene, trans-ferulic acid, rutin trihydrate, 3,4-dihydroxybenzoic acid, tannic acid and quercetin by liberating them from the plant matrix.
Originality/value
The results thus indicate that controlled microwave heating could be an effective approach for the reduction of anti-nutritional factors besides leading to an overall improvement in antioxidant potential and volatile and phenolic compounds. This novel technological approach can proliferate the use of plum kernels in different diversified food formulations.
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Adam Wisniewski, Maciej Malicki and Wojciech Manaj
This paper aims to enhance the selection of the best material of the rocket engine combustion chamber. The chamber has been destroyed during dynamometer tests, and the…
Abstract
Purpose
This paper aims to enhance the selection of the best material of the rocket engine combustion chamber. The chamber has been destroyed during dynamometer tests, and the goal of this inspection is to verify the nature of the damage in the context of checking the usefulness of this type of graphite for the combustion chamber construction.
Design/methodology/approach
This paper presents the results of visual and microscopic inspection of the rocket engine combustion chamber of Ø50 × 165 mm in dimension, which was made of R type graphite.
Findings
An analysis of the fracture surface shows that in the inspected combustion chamber voids and inclusions are present. EDS analysis of the fracture surface shows that in the inspected combustion chamber inclusions are present which have a relatively high amount of elements like: Ti, C, S, V, Si, O and a relatively small amount of Fe and Ni.
Research limitations/implications
Research limitations is concerned the failure analysis by a scanning electron microscope (SEM) Zeiss EVO 25 MA with EDS detector: Brüker X Flash Detector 5010 125 eV and Espirit 1.9.0.2176 EDS software.
Practical implications
Designing of the engine combustion chamber the researches can select the best of the rocket engine combustion chamber, made of R type graphite, with the minimum voids and inclusions to decrease the possibility of bursting of this chamber.
Originality/value
The most dangerous issues in the inspected combustion chamber during an outflow are hot gases as a result of high fuel combustion temperature, so it causes the nozzle heating and the engine stress increase of visible inclusions in cross-sections.
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