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1 – 9 of 9Natalia A. Volgina and Yuanlong Wang
China is one of the fastest-growing countries; it holds important positions in many product markets, including the global automotive market. The objectives of this study are as…
Abstract
China is one of the fastest-growing countries; it holds important positions in many product markets, including the global automotive market. The objectives of this study are as follows: to assess the position of China in the global automotive production, global automotive exports and imports; and also compare the position of China on these indicators with the main competing countries. In this regard, the method of comparative analysis has become the main research method. Based on the analysis and calculations performed, the authors came to some conclusions. China came out on top in the production and export of automotive products, overtaking key competitors, including the United States, Japan, Germany and India. This was achieved through an effective combination of trade, investment and industrial policy instruments. The decline in production and export of cars during the COVID-19 coronavirus pandemic was minimal in China compared to competitors, which is explained by an efficiently formed supply chain, as well as the presence of transport hubs (7 of the 10 largest sea container ports are located in China). The authors believe that future trends in the development of the Chinese automotive industry will be associated with the renewal of production to reduce environmental pollution and restructuring of supply chains to further localize the production of intermediate components for the automotive industry.
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Yuanlong Chen, Tingbo Hou and Xiaochao Zhou
The purpose of this paper is to ensure adequate thermal management to remove and dissipate the heat produced by a light-emitting diode (LED) and to guarantee reliable and safe…
Abstract
Purpose
The purpose of this paper is to ensure adequate thermal management to remove and dissipate the heat produced by a light-emitting diode (LED) and to guarantee reliable and safe operation.
Design/methodology/approach
A three-dimensional (3-D) computational fluid dynamics (CFD) model was used to analyze the distribution of fluid velocities among microchannels at four different aspect ratios.
Findings
The results showed that at the same inlet flow rate, the larger the aspect ratio of the microchannels, the better the uniformity of the internal fluid velocity and thus better the heat dissipation performance on the surface of the high-power LED chip. In addition, the thermal performance of a high-power LED water cooling system with four different aspect ratios’ microchannel structures is further studied experimentally. Specifically, the coupling effect between the fluid velocity distribution in the microchannels and the heat dissipation performance of a high-power LED water cooling system is qualitatively analyzed and compared with the simulation results of the fluid velocity distribution. The results fully demonstrated that a larger aspect ratio of the microchannels results in better heat dissipation performance on the surface of the high-power LED chip.
Originality/value
Optimizing the structural parameters to facilitate a relatively uniform velocity distribution to improve the water cooling system performance may be a key factor to be considered.
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Xiaobo Shi, Yaning Qiao, Xinyu Zhao, Yan Liu, Chenchen Liu, Ruopeng Huang and Yuanlong Cui
Modern subway transportation systems need to satisfy increasing safety demands to rapidly evacuate passengers under hazardous emergency circumstances, such as fires, accidents or…
Abstract
Purpose
Modern subway transportation systems need to satisfy increasing safety demands to rapidly evacuate passengers under hazardous emergency circumstances, such as fires, accidents or terrorist attacks, to reduce passenger injuries or life losses. The emergency evacuation capacity (EEC) of a subway station needs to be revised timely, in case passenger demand increases or the evacuation route changes in the future. However, traditional ways of estimating EEC, e.g. fire drills are time- and resource-consuming and are difficult to revise from time to time. The purpose of this study is to establish an intuitive modelling approach to increase the EEC of subway stations in a stepwised manner.
Design/methodology/approach
This study develops an approach to combine agent-based evacuation modelling and building information modelling (BIM) technology to estimate the total evacuation time of a subway station.
Findings
Evacuation time can be saved (33% in the studied case) from iterative improvements including stopping escalators running against the evacuation flow and modifying the geometry around escalator exits. Such iterative improvements rely on integrating agent-based modelling and BIM.
Originality/value
The agent-based model can provide a more realistic simulation of intelligent individual movements under emergency circumstances and provides precise feedback on locations of evacuation bottlenecks. This study also examined the effectiveness of two rounds of stepwise improvements in terms of operation or design to increase the EEC of the station.
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Dimitrios Kafetzopoulos, Spiridoula Margariti, Chrysostomos Stylios, Eleni Arvaniti and Panagiotis Kafetzopoulos
The objective of this study is to improve the food supply chain performance taking into consideration the fundamental concepts of traceability by combining the current frameworks…
Abstract
Purpose
The objective of this study is to improve the food supply chain performance taking into consideration the fundamental concepts of traceability by combining the current frameworks, its principles, its implications and the emerging technologies.
Design/methodology/approach
A narrative literature review of already existing empirical research on traceability systems was conducted resulting in 862 relevant papers. Following a step-by-step sampling process, the authors ended up with 46 final samples for the literature review.
Findings
The main findings of this study include the various descriptions of the architecture of traceability systems, the different sources enabling this practice, the common desirable attributes, and the enabling technologies for the deployment and implementation of traceability systems. Moreover, several technological solutions are presented, which are currently available for traceability systems, and finally, opportunities for future research are provided.
Practical implications
It provides an insight, which could affect the implementation process of traceability in the food supply chain and consequently the effective management of a food traceability system (FTS). Managers will be able to create a traceability system, which meets users' requirements, thus enhancing the value of products and food companies.
Originality/value
This study contributes to the food supply chain and the traceability systems literature by creating a holistic picture of where something has been and where it should go. It is a starting point for each food company to design and manage its traceability system more effectively.
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Ufana Riaz, S.M. Ashraf and Sharif Ahmad
The purpose of this paper is to report a comparative study of conducting polymer (CP) dispersed oil polyurethane coatings derived from a sustainable resource, i.e. polyaniline…
Abstract
Purpose
The purpose of this paper is to report a comparative study of conducting polymer (CP) dispersed oil polyurethane coatings derived from a sustainable resource, i.e. polyaniline (PANI)/coconut oil polyesteramide urethane (CPEAU) and poly(1‐naphthylamine) (PNA)/linseed oil polyurethane (LPUA) coatings.
Design/methodology/approach
The coatings were prepared chemically and were characterized for their physico‐chemical, physico‐mechanical, corrosion protective efficiency, and open circuit potential measurements. The morphological analysis of the corroded carbon steel (CS), coated uncorroded CS, and coated corroded CS specimens, was carried out by SEM analysis.
Findings
The study revealed that the presence of a CP enhanced the corrosion protective efficiency of the sustainable resource‐based organic coatings. The type of CP used also played a major role in defining the corrosion resistance behavior of the coating materials.
Originality/value
The comparative study of anticorrosive properties of CP with oil‐based polyurethane blends has been studied for the first time.
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Zehra Gulru Cam Taskiran, Murat Taşkıran, Mehmet Kıllıoğlu, Nihan Kahraman and Herman Sedef
In this work, a true random number generator is designed by sampling the double-scroll analog continuous-time chaotic circuit signals.
Abstract
Purpose
In this work, a true random number generator is designed by sampling the double-scroll analog continuous-time chaotic circuit signals.
Methodology
A Chua circuit based on memristance simulator is designed to obtain a non-linear term for a chaotic dynamic system. It is implemented on the board by using commercially available integrated circuits and passive elements. A low precision ADC which is commonly found in the market is used to sample the chaotic signals. The mathematical analysis of the chaotic circuit is verified by experimental results.
Originality
It is aimed to be one of the pioneering studies (including low precision ADC) in the literature on the implementation of memristive chaotic random number generators.
Findings
Two new methods are proposed for post-processing and creating random bit array using XOR operator and J-K flip flop. The bit stream obtained by a full-hardware implementation successfully passed the NIST-800-22 test. In this respect, the availability of the memristance simulator circuit, memristive chaotic double-scroll attractor, proposed random bit algorithm and the randomness of the memristive analog continuous-time chaotic true number generator were also verified.
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Mohd Anwar Zawawi, Sinead O'Keffe and Elfed Lewis
The purpose of this paper is to provide a comparative review of intensity‐modulated fiber optic sensors with non‐optical sensors for health monitoring applications, from the…
Abstract
Purpose
The purpose of this paper is to provide a comparative review of intensity‐modulated fiber optic sensors with non‐optical sensors for health monitoring applications, from the current research activities in the area.
Design/methodology/approach
A range of published research work in sensor design for four different health monitoring applications, including, lumbar spine bending, upper and lower limb motion tracking, respiration and heart rate monitoring, are presented and discussed in terms of their respective advantages and limitations.
Findings
This paper provides information on the various types of sensors applied into the health monitoring area. The sensing techniques of the fiber optic sensor for the stated applications are focused and compared in details to highlight their contributions.
Originality/value
A comparative review of published work is illustrated in an informative table content, to allow a clear idea of the current sensing approaches for health monitoring applications.
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S.A. Umoren, U.M. Eduok and M.M. Solomon
The purpose of this paper is to investigate the effect of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and blended formulations on the corrosion inhibition of aluminium…
Abstract
Purpose
The purpose of this paper is to investigate the effect of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and blended formulations on the corrosion inhibition of aluminium in HCl solutions at 30-60°C and to study the mechanism of action.
Design/methodology/approach
The inhibitive effect of the homopolymers and polymer blend was assessed using weight loss and hydrogen evolution methods at 30 and 60°C. The morphology of the corroding aluminium surface without and with the additives was visualized using atomic force microscopy. The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.
Findings
Results obtained show that inhibition efficiency (η%) increases with increase in concentration of the polymers but decreases with increase in temperature. The inhibition efficiency of the homopolymers and their blends decreased with rise in temperature. Inhibition efficiency was found to be synergistically enhanced on blending the two homopolymers with highest inhibition efficiency obtained for (PEG:PVP) blending ratio of 1:3. The phenomenon of physical adsorption is proposed from the trend of inhibition efficiency with temperature.
Research limitations/implications
The mechanistic aspect of the corrosion inhibition can be better understood using electrochemical studies such as potentiodynamic polarization and electrochemical impedance spectroscopy.
Originality/value
Studies involving the use of polymer blends/mixtures as corrosion inhibitor for metals in corrosive environments are scarce. The results suggest that the mixture could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the use of polymer–polymer mixtures to control acid-induced corrosion of metal.
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