Search results

The purpose of this paper is to propose modelling of the noise of an improved method for the measurement of small displacement and vibrations. It is based on a novel method for overcoming DC drift in RF subcarrier phase detection scheme.

The method works in open loop and is characterized by low distortions, good signal‐to‐noise ratio and rather low cost.

Considering a stationary Gaussian stochastic process, the paper evaluated and modelled the power spectral density and the probability density against the phase error and the phase noise parameter.

This offers an improvement of vibration, displacement and seismic sensors.

Based on a novel method for overcoming DC drift in RF sub‐carrier phase detection scheme for fibre optic sensors, an improved method for displacement and vibration measurement is proposed. The presented method is characterized by rather low distortions in the modulation process and small distances measurement, low distortions and low‐cost electronic systems.

The purpose of this paper is to suggest a procedure which makes it possible to reduce the radial vibrations of doubly salient switched reluctance motors (SRMs).

An analytical method for the SRM radial vibration determination is first described. It is then extended to the active vibration reduction. An auxiliary winding equips the stator. The paper explains how the corresponding currents have to be adjusted to achieve a simple and robust control, with a special emphasis about the compatibility of the main and auxiliary supplies and about the reduction control principle. At last, an example of drastic noise reduction is presented.

The proposed method makes possible to define the theoretical vibration spectrum of SRM and thus it gives the major components to be reduced. The feasibility of automating the principle of active reduction is shown. The process of active reduction shows that a vibration component can be diminished by over 90 percent.

The active reduction is applied for reducing one component of the vibration spectrum. Future developments will focus on the simultaneous reduction of several components of vibration spectrum.

The method offers an automated process to reduce considerably the component of highest amplitude in the vibration spectrum.

The aim of this work is to synthesize neopentyl glycol oligoesters based on adipic acid and rapeseed oil (NOAR) which may be used as the renewable and environmentally acceptable base fluids to replace mineral oils in the future.

Oligomeric intermediates were synthesized in the first esterification of neopentyl glycol with adipic acid and characterized by Gas Chromatography-Mass Spectrometer (GC-MS) to calculate the average oligomerisation degree. NOAR were synthesized in the second esterification of oligomeric intermediates with rapeseed oil fatty acid. The effects of average oligomerisation degree on the viscosity, viscosity index, pour point, oxidative stability and biodegradability of NOAR were investigated; the tribological properties and thermal stability of NOAR were evaluated by four-ball tribometer and TGA, respectively.

Results show that with the increase of average oligomerisation degree from 2.10 to 4.34, the viscosity of NOAR increased from 101.1 to 182.0 (mm2/s) at 40°C and 18.3 to 30.1 (mm2/s) at 100°, respectively, and their oxidation stability can be improved as well. The yields of NOAR were 83.3-89.4 per cent, and the evaluated properties were as follows: viscosity index of over 200, pour point of below −43°C, biodegradation rate of more than 96 per cent, maximum non-seizure load (PB value) of 784 N, wear scar diameters of 0.40 mm and thermal decomposition temperature of higher than 300°C.

This work provides a method to synthesize rapeseed oil-based oligoesters which can serve as the renewable and environmentally acceptable base fluids with tunable viscosity by controlling the oligomerisation degree of esterification.

The built environment is responsible for approximately 40% of the world’s energy consumption, 30% of raw material use, 25% of solid waste, 25% of water use, 12% of land use and 33% of greenhouse gas emissions. Thus, environmental improvement and decarbonization are becoming increasingly critical objectives for the construction industry. Sustainable construction can be achieved through several practices, including: considering life-cycle assessment, circular construction, resource efficiency and waste management and providing eco-efficient materials, reducing energy demands and consumption and incorporating low-carbon technologies and renewable energy sources. To achieve sustainable construction goals, it is critical to educate the future workforce about decarbonization, circular construction and how to overcome the challenges involved in transitioning to sustainable construction. This study aims to understand the gap in student knowledge related to decarbonization and circular construction and the importance of incorporating these topics in civil engineering and construction management curricula.

This study surveyed 120 undergraduate and graduate students at one of the largest minority-serving institutions in the USA to understand the gap in student knowledge related to decarbonization and circular construction as well as the importance of incorporating these topics in civil engineering and construction management curricula. The authors conducted several statistical measures to assess the consistency, reliability and adequacy of the sample size, including the Kaiser–Meyer–Olkin measure of sampling adequacy, the normality test to evaluate the appropriateness of using an ordered probit regression analysis and a multicollinearity test to observe the correlation between independent variables. The data was analyzed using ordered probit regression analysis to investigate the need for a curriculum that serves in educating students about decarbonization and circular construction.

The results of this research highlight the gaps in students’ knowledge pertaining to sustainable practices and the importance of providing future construction workforce with such knowledge to tackle global inevitable challenges.

The findings of this study contribute to sustainable construction bodies of knowledge by advocating for a reformed curriculum to prepare the future workforce and adopt less carbonized, more circular approaches within the engineering and construction industry.

This paper aims to investigate the efficacy of teeth flux sensors in detecting, locating and assessing the severity of short-circuit faults in the stator windings of induction machines.

The experimental study involves inducing short-circuit winding turn variations on the induction machine’s stator and continuously measuring the RMS values across teeth flux sensors. Two crucial steps are taken for machine diagnosis: measurements under load operating conditions for fault detection and measurements under no-load conditions to determine fault location and severity.

The experimental results demonstrate that the proposed approach using teeth flux sensors is reliable and effective in detecting, locating and evaluating the severity of stator winding faults.

While this study focuses on short-circuit faults, future research could explore other fault types and alternative sensor configurations to enhance the comprehensiveness of fault diagnosis.

The methodology outlined in this paper holds the potential to significantly reduce maintenance time and costs for induction machines, leading to substantial savings for companies.

This research contributes to the field by presenting an innovative approach that uses teeth flux sensors for a comprehensive fault diagnosis in induction machines. The originality lies in the effectiveness of this approach in providing reliable fault detection, location and severity evaluation.

This paper aims to solve the problems molybdenum disulfide (MoS₂) nanosheets suffer from inadequate dispersion stability and form a weak lubricating film on the friction surface, which severely limits their application as lubricant additives.

MoS₂/C₆₀ nanocomposites were prepared by synthesizing molybdenum disulfide (MoS₂) nanosheets on the surface of hydrochloric acid-activated fullerenes (C₆₀) by in situ hydrothermal method. The composition, structure and morphology of MoS₂/C₆₀ nanocomposites were characterized. Through the high-frequency reciprocating tribology test, its potential as a lubricant additive was evaluated.

MoS₂/C₆₀ nanocomposites that were prepared showed good dispersion in dioctyl sebacate (DOS). When 0.5 Wt.% MoS₂/C₆₀ was added, the friction reduction performance and wear resistance improved by 54.5% and 62.7%, respectively.

MoS₂/C₆₀ composite nanoparticles were prepared by in-situ formation of MoS₂ nanosheets on the surface of C₆₀ activated by HCl through hydrothermal method and were used as potential lubricating oil additives.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2023-0321/

Trafficking in women is among the most serious human rights challenges. Extant studies of the media images of trafficked women suggest that these images emphasize women’s victimization and contribute to the reproduction of existing gender inequalities and power relations. In this case study of Moldovan media and scientific discourse, the authors sought to identify the images of trafficked women that are presented in the print media, on the one hand, and the scientific discourse, on the other. The authors also asked whether those images portray trafficked women in a stereotypical manner. The findings of this chapter revealed that the most prevalent images in both discourses are trafficked women as victims, commodities, and slaves. Both media and scientific discourses include gender oppression, domestic violence, and poverty as dimensions of the victim image. However, these three aspects of the victim image are treated more comprehensively by the scientific discourse. Some of the most prominent differences between the two types of discourses are the absence of women’s agency in the media discourse and absence of the men’s nature as a dimension of the victim image in the scientific discourse. The authors conclude by suggesting that, despite these differences, the images present in both types of discourse could be used to justify policies that would limit the migration of women but fail to effectively address the root causes of sex trafficking in women.

Design-thinking (DT) in education has attracted significant interest from practitioners and academics, as it proffers new-age thinking to transform learning processes. This paper synthesises extant literature and identifies the current intellectual frontiers.

First, a systematic-literature-review was undertaken employing a robust process of selecting papers (from 1986 to 2022) by reading titles, abstracts and keywords based on a required criterion, backward–forward chaining and strict quality evaluations. Next, a bibliometric analysis was undertaken using VOSviewer. Finally, text analysis using RStudio was done to trace the implications of past work and future directions.

At first, we identify and explain 12 clusters through bibliometric coupling that include “interdisciplinary-area”, “futuristic-learning”, “design-process” and “design-education”, amongst others. We explain each of these clusters later in the text. Science, Technology, Engineering, Arts and Mathematics (STEAM), management education, design and change, teacher training, entrepreneurship education and technology, digital learning, gifted education and course development) Secondly, through co-word-analysis, we identify and explain four additional clusters that include “business education and pedagogy”, “content and learning environment”, “participants and outcome” and finally, “thinking-processes”. Based on this finding, we believe that the future holds a very positive presence sentiment for design thinking and education (DT&E) in changing the 21st century learning.

For investigating many contemporary challenges related to DT&E, like virtual reality experiential learning, sustainability education, organisational learning and management training, etc. have been outlined.

Academics may come up with new or improved courses for the implementation of DT in educational settings and policymakers may inculcate design labs in the curricula to fortify academic excellence. Managers who would employ DT in their training, development and policy design, amongst others, could end up gaining a competitive advantage in the marketplace.

This study conducted a comprehensive review of the field, which to our limited knowledge, no prior studies have been done so far. Besides, the study also outlines interesting research questions for future research.