Hua Ding, Yanhong Huang, Jianqi Shi, Qi Shi and Yang Yang
Automatic guided vehicles (AGVs) are widely used in industrial fields. But most control strategies merely take the lateral force into consideration. This will reduce the accuracy…
Abstract
Purpose
Automatic guided vehicles (AGVs) are widely used in industrial fields. But most control strategies merely take the lateral force into consideration. This will reduce the accuracy, stability and robustness and will pay additional costs. Therefore, this paper aims to design a control strategy that initially considers lateral force. Thereby, it will improve the accuracy, stability and robustness and reduce the overall cost of AGV.
Design/methodology/approach
To achieve the goal of comprehensively improving AGV operating performance, this paper presents a new scheme, combining the dual-wheeled chassis model (DCM) using proportional–integral–differential (PID) control and a supporting quick response (QR) code navigation technology. DCM is the core, which analyzes the deviation caused by lateral force. Then, DCM with PID control by the control law is combined to suppress the errors. Meanwhile, QR code navigation technology provides effective data support for the control strategy.
Findings
Most AGV experiments are carried out in a standard environment. However, this study prepares unfavorable scenarios and operating conditions for the experiments that generate detailed data to demonstrate this study’s strategy, which can make an accurate, stable and robust operation process of AGV under various adverse environmental and mechanical factors.
Originality/value
This study proposed DCM, fully considering lateral force and converting the force into velocity. Subsequently, PID controls the speed of two wheels to reduce the error. QR code provides an efficient and low – cost way to obtain information. The three are cleverly combined as a novel industrial AGV control strategy, which can comprehensively improve the operating performance while reducing overall costs.
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Huatian Wang, Hua Ding and Xiansui Kong
Technostress is becoming one of the main challenges among employees in the increasingly digital work context. Following the job demands-resources (JD-R) theory, this study aims to…
Abstract
Purpose
Technostress is becoming one of the main challenges among employees in the increasingly digital work context. Following the job demands-resources (JD-R) theory, this study aims to understand how technostress (e.g. techno-overload, techno-complexity, techno-insecurity and techno-uncertainty) decreases employees’ work well-being through exhausting one’s emotional and physical resources (i.e. work exhaustion), and to what extent workplace knowledge diversity could buffer this relationship.
Design/methodology/approach
The authors collected three-wave data of 235 employees from three manufacturing companies in China. They conducted a moderated mediation model to test their hypotheses.
Findings
The results showed that work exhaustion mediated the relationship between technostress and employee work well-being and that perceived workplace knowledge diversity buffered this indirect effect.
Originality/value
This study might be one of the first attempts using the JD-R theory together with a three-wave longitudinal survey design to empirically examine the mediating role of work exhaustion and the moderating role of workplace knowledge diversity. The authors contribute to the information and technology management literature by underscoring the importance of being aware of technostress and managing technology-induced work exhaustion. They highlight that a knowledge-diverse work environment is an essential context that can help employees to handle difficult and complex tasks presented by various technologies and alleviate experienced technostress.
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Loretta Bortey, David J. Edwards, Chris Roberts and Iain Rillie
Safety research has focused on drivers, pedestrians and vehicles, with scarce attention given to highway traffic officers (HTOs). This paper develops a robust prediction model…
Abstract
Purpose
Safety research has focused on drivers, pedestrians and vehicles, with scarce attention given to highway traffic officers (HTOs). This paper develops a robust prediction model which enables highway safety authorities to predict exclusive incidents occurring on the highway such as incursions and environmental hazards, respond effectively to diverse safety risk incident scenarios and aid in timely safety precautions to minimise HTO incidents.
Design/methodology/approach
Using data from a highway incident database, a supervised machine learning method that employs three algorithms [namely Support Vector Machine (SVM), Random Forests (RF) and Naïve Bayes (NB)] was applied, and their performances were comparatively analysed. Three data balancing algorithms were also applied to handle the class imbalance challenge. A five-phase sequential method, which includes (1) data collection, (2) data pre-processing, (3) model selection, (4) data balancing and (5) model evaluation, was implemented.
Findings
The findings indicate that SVM with a polynomial kernel combined with the Synthetic Minority Over-sampling Technique (SMOTE) algorithm is the best model to predict the various incidents, and the Random Under-sampling (RU) algorithm was the most inefficient in improving model accuracy. Weather/visibility, age range and location were the most significant factors in predicting highway incidents.
Originality/value
This is the first study to develop a prediction model for HTOs and utilise an incident database solely dedicated to HTOs to forecast various incident outcomes in highway operations. The prediction model will provide evidence-based information to safety officers to train HTOs on impending risks predicted by the model thereby equipping workers with resilient shocks such as awareness, anticipation and flexibility.
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Michele Ciotti, Giampaolo Campana and Mattia Mele
This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature, the aim…
Abstract
Purpose
This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature, the aim is to provide an updated map of trends and gaps in this relevant research field. Several technologies and investigation methods are examined, thus giving an overview and analysis of the growing body of research.
Design/methodology/approach
Permutations of keywords, which concern materials, technologies and the accuracy of thermoplastic polymeric parts fabricated by AM, are used for a systematic search in peer-review databases. The selected articles are screened and ranked to identify those that are more relevant. A bibliometric analysis is performed based on investigated materials and applied technologies of published papers. Finally, each paper is categorised and discussed by considering the implemented research methods.
Findings
The interest in the accuracy of additively manufactured thermoplastics is increasing. The principal sources of inaccuracies are those shrinkages occurring during part solidification. The analysis of the research methods shows a predominance of empirical approaches. Due to the experimental context, those achievements have consequently limited applicability. Analytical and numerical models, which generally require huge computational costs when applied to complex products, are also numerous and are investigated in detail. Several articles deal with artificial intelligence tools and are gaining more and more attention.
Originality/value
The cross-technology survey on the accuracy issue highlights the common critical aspects of thermoplastics transformed by AM. An updated map of the recent research literature is achieved. The analysis shows the advantages and limitations of different research methods in this field, providing an overview of research trends and gaps.
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David McHardy Reid, Guotai Chi, Zhi Chong Zhao and Ilan Alon
Performed over a five-year time horizon, this paper aims to analyze the progression rates of technological innovation across 15 sub-provincial Chinese cities. The authors quantify…
Abstract
Purpose
Performed over a five-year time horizon, this paper aims to analyze the progression rates of technological innovation across 15 sub-provincial Chinese cities. The authors quantify and rate innovation performance, then rank the cities based on a purpose-built index designed to gauge the rate of technological progress.
Design/methodology/approach
Using the inferior constraint method, and a variety of national sources of data, the authors construct an innovation index based in part on new product sales revenue, proportion of college students, research and development expenditure of industrial enterprises in relation to gross industrial output value, contract deals in technical markets per capita, hazard-free treatment rate of waste, enterprises with technical development agencies accounts for industrial enterprises, number of high-tech enterprises and invention patent ownership per million population.
Findings
The findings provide a methodology for indexing cities, with 15 Chinese provincial cities as examples. Among the top five cities with the highest technological innovation index were Shenzhen, Nanjing, Guangzhou, Hangzhou and Wuhan. In the bottom were Shenyang, Changchun, Dalian, Xi’an and Harbin.
Research limitations/implications
This study applied a new model of innovation at the city level for China. Application to other industries (real estate, manufacturing, etc.) and countries will extend boundaries of this model and show its wider applicability.
Practical implications
Companies can use this research and methodology when seeking new investments in high tech and innovative products. Locations offering more hospitable environments should be prioritized ceteris paribus.
Originality/value
One weakness of much of the international business and competitiveness literature is that it often views the country as the primary unit of analysis. In this way, nuanced views of the institutional environments within countries are often overlooked. This paper proposes a measure of regional rates of innovativeness across China.
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José Marcelo Honório Ferreira Barros, Sálvio Lima de Carvalho Neto, Ana Julia Dal Forno, Rita de Cássia Siqueira Curto Valle and José Alexandre Borges Valle
The primary goal of domestic washing and drying processes is to deliver clean and dry clothes, but they often result in excessive wrinkling of fabrics. This study aims to evaluate…
Abstract
Purpose
The primary goal of domestic washing and drying processes is to deliver clean and dry clothes, but they often result in excessive wrinkling of fabrics. This study aims to evaluate the wrinkling of linen fabric using image processing techniques after these processes and to quantify various drying performance indicators.
Design/methodology/approach
An image processing software was developed to quantify the smoothness level of linen fabrics subjected to domestic washing and drying processes. Additionally, different washing parameters in a front-loading washer that affect fabric wrinkling were evaluated. Three drying cycles (easy-iron, normal and extra-dry) in a condensation dryer were also analyzed in terms of moisture and fabric wrinkling parameters.
Findings
The results demonstrated a close relationship between water extraction from the fabrics and wrinkle formation. The shortest drying cycle with milder temperatures produced wetter and less wrinkled fabrics at the end of the drying cycle. Conversely, the longer, higher-temperature programs completely removed the moisture from the linen fabrics but resulted in greater wrinkling.
Originality/value
The development of an image processing technique to quantify the wrinkling of linen fabric allowed for more objective evaluation of this parameter. Additionally, this study allowed for the correlation of various drying indicators with the wrinkling generated in the linen fabric.
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Hong Lu, Bin Liang and Deena DeVore
The victim’s rights movement and restorative justice (RJ) have gained momentum around the world. More laws and policies have focused on crime victims and their families. Western…
Abstract
The victim’s rights movement and restorative justice (RJ) have gained momentum around the world. More laws and policies have focused on crime victims and their families. Western literature suggests that the victim’s family suffers physical, emotional, and financial tolls and that the power of the victim’s family in pursuing justice for their loved ones remains limited. This is particularly concerning within the political and legal context of the abolitionist movement, innocence project, and human rights groups’ campaigns against police torture. Grounded in the perspectives of RJ and Chinese legal culture, this study examines the victim’s family, represented by Ding and senior Yu, of the Nian Bin capital murder case. Drawing on published reports and using the thematic content analysis method, this study examines the following aspects of victim’s family in a death penalty case: 1) victim family’s physical, emotional, and financial tolls; 2) victims’ family and the criminal justice system; 3) victims’ family and the media; and 4) the relationship between the victims’ and the accused’s families. This study concludes with discussions of the competing goals of families impacted by a crime and RJ practices that would help mitigate the loss of the victim’s family and enhance their confidence in the criminal justice system.
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A study on predicting the stiffness of woven fabric using an artificial neural network was conducted. A neural network system trained with a back-propagation algorithm performed…
Abstract
A study on predicting the stiffness of woven fabric using an artificial neural network was conducted. A neural network system trained with a back-propagation algorithm performed functional mapping between the fabric surface and mechanical properties and the evaluated hand stiffness values. The correlation coefficient was applied to confirm the effectiveness of the model that had been developed. It was established that a hand characteristic value of stiffness can be predicted from the mechanical and surface properties of fabric.
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Robin Hanson, Lars Medbo and Per Medbo
The purpose of this paper is to determine how kitting, compared to continuous supply, affects the time spent by the assembler fetching parts in manual assembly.
Abstract
Purpose
The purpose of this paper is to determine how kitting, compared to continuous supply, affects the time spent by the assembler fetching parts in manual assembly.
Design/methodology/approach
The paper is based on an experimental setup at the Saab Automobile assembly plant in Trollhättan, Sweden. Experienced assemblers were studied as they performed the same assembly operations in ten different configurations. Each configuration consisted of a different arrangement in terms of how parts were presented. The use of kits to present parts was compared to parts presentation through continuous supply, where each part number was presented in a separate container.
Findings
The time for fetching parts is significantly shorter when parts are presented through kitting instead of through continuous supply. Furthermore, the shorter fetching time is not just related to a shorter distance between assembly object and parts presentation, which can often be achieved through kitting. The reduction of time spent searching for parts is also considerable.
Practical implications
The results of the paper provide valuable input in the design of assembly and materials supply systems, as they enable a better understanding of the relative performance of the materials feeding principles of kitting and continuous supply.
Originality/value
Previous studies of kitting and its impact on assembly are mostly conceptual or qualitative, whereas quantitative studies are scarce. The current paper provides a substantial contribution by quantifying the effects that kitting, compared to continuous supply, has on the time spent fetching parts.
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Shuwen Wang, Feiyan Yan and Ao Chen
The purpose of this paper is to investigate the tribological effects of laser surface texturing (LST) and residual stress on functional surfaces.
Abstract
Purpose
The purpose of this paper is to investigate the tribological effects of laser surface texturing (LST) and residual stress on functional surfaces.
Design/methodology/approach
Three different surface textures (circular dimple, elliptical dimple and groove) with two different textured area ratios (10 and 20 per cent) are designed and fabricated by a Picosecond Nd YAG Laser machine. The friction and wear performance of textured specimens is tested using a UMT-2 friction and wear testing machine in mixed lubrication.
Findings
Test results show that elliptical dimples exhibit the best performance in wear resistance, circular dimples in friction reduction and grooves in stabilization of friction. The surfaces with larger textured area density exhibit better performance in both friction reduction and wear resistance. The improved performance of LST is the coupled effect of surface texture and residual stress.
Originality/value
The findings of this study may provide guidance for optimal design of functional surface textures in reciprocating sliding contacts under mixed or hydrodynamic lubrication, which can be used in automotive and other industrial applications.