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Flexible learning during educational disruption: a case study of teaching integrated circuits design
Get PDFTo date, there has been little written that explains how engineering-related tuition can be rapidly and effectively moved online. Furthermore, there is sparse literature written that focuses on how students can adapt to such technologies in a relatively short space of time. Finally, it is both necessary and prudent to increase discourse on the effective online teaching of technical design subjects. This paper evaluates the effectiveness of online tools such as interactive live lectures, slide annotation, and electronic whiteboard, for engaging students in electrical and electronic engineering education. The paper advances those debates by providing an evaluative analysis from the perspective of students taking an Integrated Circuits design module that was delivered during the 2020 COVID-19 crisis. The major research question is: to what extent do electrical engineering students perceive online learning tools to be useful in enhancing their sudden learning change? Responses were collected using an online questionnaire that was offered to 23 students who enrolled in the module, and a 70% completion rate was received. The findings showed that students engaged well with the technologies, and they found them easy to use and beneficial for their learning
Advanced automation and robotics for high volume labour-intensive manufacturing
Get PDFHigh volume, labour-intensive manufacturing operations pose several challenges for successful operations. It is an even bigger challenge to move away from manual dependency and shift towards automation of production processes. There seems to be no general agreement among researchers on what are the critical success factors (CSFs) on the implementation of advanced automation and robotics processes in the manufacturing environment. Success factors vary across the manufacturing industry and also organizational units. This paper attempts to elicit the opinion and perception of academic professionals with links to high volume labour-intensive manufacturing industry. A systematic literature search was conducted on the topic and semi-structured interviews were conducted with experts to gather their views on CSFs. Results from the literature search and interviews revealed that factors related to Organization Strategy, Culture, and Structure; Top management support; Past experience, staffing, and learning; Project management, planning, and control; Finance, and resource availability; Technology maturity and vendor support; to be critical for the success of the production process automation project initiatives. Findings from this study can be used as guidelines to ascertain CSFs for organizations and strategy planning. Manufacturing organizations can also use this study to evaluate their organizational readiness and enhance the level of automation further
Kinetic and thermodynamic investigations of CO2 gasification of coal chars prepared via conventional and microwave pyrolysis
Get PDFThis study examined an isothermal CO2 gasification of four chars prepared via two different methods, i.e., conventional and microwave-assisted pyrolysis, by the approach of thermogravimetric analysis. Physical, chemical, and structural behaviours of chars were examined using ultimate analysis, X-ray diffraction, and scanning electronic microscopy. Kinetic parameters were calculated by applying the shrinking unreacted core (SCM) and random pore (RPM) models. Moreover, char-CO2 gasification was further simulated by using Aspen Plus to investigate thermodynamic performances in terms of syngas composition and cold gas efficiency (CGE). The microwave-induced char has the largest C/H mass ratio and most ordered carbon structure, but the smallest gasification reactivity. Kinetic analysis indicates that the RPM is better for describing both gasification conversion and reaction rates of the studied chars, and the activation energies and pre-exponential factors varied in the range of 78.45–194.72 kJ/mol and 3.15–102,231.99 s−1, respectively. In addition, a compensation effect was noted during gasification. Finally, the microwave-derived char exhibits better thermodynamic performances than the conventional chars, with the highest CGE and CO molar concentration of 1.30% and 86.18%, respectively. Increasing the pyrolysis temperature, gasification temperature, and CO2-to-carbon molar ratio improved the CGE
Numerical simulation of circulating tumor cell separation in a dielectrophoresis based Y-Y shaped microfluidic device
Get PDFEfficient and effective separation of circulating tumor cells from biological samples to promote early diagnosis of cancer is important but challenging, especially for non-small cell lung cancer (NSCLC). In this article, a Y-Y shaped microfluidic device was designed to isolate NSCLC cells with a dielectrophoresis approach. Numerical simulations were conducted that the trajectories of cells were traced by solving the electric potential distribution and the flow field in a microchannel. The effects of inlet flow rate ratio of blood sample and buffer on separation performance were studied and optimized by the numerical investigation. Under optimal operating conditions, the separation efficiency can reach around 99%, which is achieved with 100 kHz AC, electrodes potential ranging from 1.6 V to 2.2 V, and flow rate ratio from 1.9 to 2.5. This study presents a potentially efficient, facile and low-cost route for circulating tumor cell separation
The role of social capital in expanding retail platform ecosystems
Get PDFIn the past few years, the discussion on platform ecosystems has become pervasive in strategy and information system research. Previous studies underlie the transformational nature of digital infrastructure in expanding the ecosystem. In this paper, the authors focus on the retail sector, where online retail platform owners such as Amazon and Alibaba are contending for ecosystem members and expanding by making them more physical. As ecosystem members have traditionally coordinated their network activities and resources embedded in an enabling social context, this study aims to investigate the influence of preexisting social capital possessed by ecosystem members on expansion of retail platform ecosystems. This dimension has received little attention thus far. Based on some conceptual basis discussed by extant literature and some preliminary empirical findings through our case study on Alibaba Lingshoutong (LST), a growing retail platform ecosystem, we have proposed some future research directions. © Proceedings of the 24th Pacific Asia Conference on Information Systems: Information Systems (IS) for the Future, PACIS 2020. All rights reserved
Vibration sensor placement for delamination detection in a beam structure based on the vibration-based chaotic oscillator method
Get PDFThis work aims to study the effect of sensor placement for delamination damage detection in a beam structure using a vibration-based chaotic oscillator method. A chaotic oscillator method is used due to its sensitivity to relatively small changes in measured vibration signal. The effect of vibration sensor placement to the delamination detection sensitivity for various delamination sizes is investigated. The Lyapunov Exponent (LE) is used in conjunction with the chaotic oscillator as a damage index to describe the extent of delamination damage in the laminated beam. The relationship between the damage index and sensor placement for different delamination size is studied to analyse the effect of sensor placement on detection performance. It is found that the sensor placement has a significant influence on the sensitivity of delamination detection with different delamination size
Future improvements on performance of an EU landfill directive driven municipal solid waste management for a city in England
Get PDFSustainable municipal solid waste (MSW) management is regarded as one of the key elements for achieving urban sustainability via mitigating global climate change, recycling resources and recovering energy. Landfill is considered as the least preferable disposal method and the EU Landfill Directive (ELD) announced in 1999 requires member countries to reduce the volume of landfilled biodegradable materials. The enforcement of ELD initiated the evolution of MSW management system UK. This study depicted and assessed the transition and performance of MSW management after the millennium in Nottingham via materials flow analysis (MFA), as well as appropriately selected indicators based on the concept of waste management hierarchy and targets set in waste management regulations. We observed improvements in waste reduction, material recycling, energy recovery, and landfill prevention. During the period 2001/02 to 2016/17, annual waste generation reduced from 463 kg/Ca to 361 kg/Ca, the recycling and composting share increased from 4.6% to 44.4%, and the landfill share reduced from 54.7% to 7.3%. These signs of progress are believed to be driven by the ELD and the associated policies and waste management targets established at the national and local levels. An alternative scenario with food waste and textile separation at source and utilizing anaerobic digestion to treat separately collected organic waste is proposed at the end of this paper to fulfil the high targets set by local government and we further suggest that the recycling share may be improved by educating and supporting the public on waste separation at the sources
Sampling-time harmonic control for cascaded H-bridge converters with thermal control
Get PDFCascaded H-bridge converter (CHB) is a multilevel topology that is a well-suited solution for multiple applications such as flexible ac transmission systems or motor drives. This paper is focused on a CHB where the cells present an aging mismatch. This can be caused by the maintenance operation which forces the replacement of some damaged cells of the converter with new or repaired ones. In this paper, a new improved approach of the active thermal control (ATC) of the CHB using discontinuous pulsewidth modulation (PWM) (D-PWM) is presented. The D-PWM technique is used to reduce the power losses of one cell reducing its average temperature in order to increase its remaining lifetime. However, the combination of D-PWM with traditional phase-shifted PWM (PS-PWM) introduces high harmonic distortion in the output voltage of the CHB converter at twice the carrier frequency. A detailed harmonic distortion analysis of the CHB output voltage when the D-PWM based ATC is active is presented. From this analysis, a modification of the traditional PS-PWM is derived to eliminate the harmonic distortion at twice the carrier frequency. Experimental results show how the ATC using D-PWM is achieved whereas the harmonic distortion around twice the carrier frequency is eliminated. © 1982-2012 IEEE
The wage-productivity nexus in the world factory economy
Get PDFThis paper highlights new findings on the wage-productivity nexus in the World Factory Economy. After presenting the long-run macro-elasticity characterizing the phase of Chinese economic development since the eighties, we look at the wage-productivity nexus from a micro level perspective using a detailed firm-level dataset covering the period of ownership restructuring (1998-2007). A few results are quite robust under different estimation strategies. First, throughout the impressive Chinese economic miracle, elasticities of real wages to productivities – that is the ratios of rates of variations of the former to the latter – are always positive both under pooled and longitudinal estimates, both at firm- and sectoral-levels. Second, such elasticities are dramatically low, and falling in many distinct phases since the late seventies. That is, even in the manufacturing sector, the distribution of gains from the impressive labour productivity growth appears to be markedly uneven. Finally, third, governance institutions seem to matter a lot, with the majority of ownership types exhibiting firm-specific wage determination processes. The low elasticities of wages to productivity are plausibly the consequence of the massive flow of migrant workers from the rural areas to the coasts, somewhat resembling the early phase of the English Industrial Revolution with the pattern of enclosure in the country-side and massive migrations to the industrial towns
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