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This study aims to focus on the heat treatment influence on the corrosion resistance, adhesion of Streptococcus mutans and mechanical properties of CoCrMo alloys manufactured by the selective laser melting (SLM).

CoCrMo alloys were manufactured using the Dimetal-100 machine. X-ray diffraction (XRD), metallographic analysis, scanning electron microscopy (SEM), electrochemical corrosion, Vickers microhardness and tensile tests were used to characterize SLM-produced CoCrMo alloys and compare them with the ones manufactured by casting and with the ASTM F75 standard.

The electrochemical results showed that SLM900 samples had the best corrosion resistance in artificial saliva. The adhesion results showed least propagation and overall quantity of Streptococcus mutans on the SLM900 sample. The microhardness, tensile and yield strength of As-SLM, SLM900 and SLM1200D samples were measured according to the ASTM F75 standard. The elongation of SLM900 was less than 8 per cent, which does not meet the standard specifications. Analysis of the fracture morphology showed that the fracture mechanisms of As-SLM and SLM1200D belong to the quasi-cleavage fracture type, and the mechanical fracture mechanism of SLM900 can be characterized as brittle fracture.

This paper presents the adhesion properties of Streptococcus mutans on the surface of CoCrMo alloys manufactured by SLM and proposes how to regulate the effect of the heat treatment on the corrosion resistance and mechanical properties of CoCrMo alloys manufactured by SLM.

The purpose of this paper is to develop a novel active disturbance rejection attitude controller for quadrotors and propose a controller parameters identification approach to obtain better control results.

Aiming at the problem that quadrotor is susceptible to disturbance in outdoor flight, the improved active disturbance rejection control (IADRC) is applied to design attitude controller. To overcome the difficulty that adjusting the parameters of IADRC controller manually is complex, paired coevolution pigeon-inspired optimization (PCPIO) algorithm is used to optimize the control parameters.

The IADRC, where nonlinear state error feedback control law is replaced by non-singular fast terminal sliding mode control law and a third-order tracking differentiator is designed for second derivative of the state, has higher control accuracy and better robustness than ADRC. The improved PIO algorithm based on evolutionary mechanism, named PCPIO, is proposed. The optimal parameters of ADRC controller are found by PCPIO with the optimization criterion of integral of time-weighted absolute value of the error. The effectiveness of the proposed method is verified by a series of simulation experiments.

IADRC can improve the accuracy of attitude control of quadrotor and resist external interference more effectively. The proposed PCPIO algorithm can be easily applied to practice and can help the design of the quadrotor control system.

An improved active disturbance rejection controller is designed for quadrotor attitude control, and a hybrid model of PIO and evolution mechanism is proposed for parameters identification of the controller.

It is widely known that fast-fashion retailers are struggling to keep up with consumer attention for quick responses within the fashion industry. With the advance of Internet and e-commerce, consumers prefer to purchase online. Online platform information has become an essential source for exploring consumer attention. However, there is often a mismatch between the information provided by retailers and the feedback received from consumers, leading to an imbalance between the supply side and demand side of online information. The purpose of this study is therefore to provide a unified approach to discover consumer attention from the design topic aspect by revealing the information imbalance between supply side and demand side.

To address the issue of online information imbalance and discover consumer attention, this study proposed an approach that focuses on the design topic perspective. The design topic is a collection of design elements that represent a clothing-design feature more comprehensively and accurately compared to a single design element. The proposed approach begins with generating design topics through topic modeling based on online information provided by retailers on e-commerce platforms. Two indicators, influence degree and attention degree, are then used to quantify the intensity of supply information and consumer attention related to design topics. Finally, design topic strategy diagrams are constructed to reveal information imbalance and discover consumer attention.

The experimental case demonstrates the existence of information imbalance, indicating that the intensity of supply information and consumer attention from the perspective of design topics is not uniform, although both follow the Pareto principle. The results of consumer attention distribution with heavy power-law tails are consistent with current research findings. This further demonstrates that the proposed approach is capable of discovering consumer attention in the design topic strategy diagrams.

The issue of information imbalance between retailers and consumers poses a challenge in keeping up with customer attention. The proposed approach offers a practical solution by visually identifying the symptoms of information imbalance and discovering consumer attention through design topic strategy diagrams. This approach provides fast-fashion retailers with a valuable reference to seize market opportunities, improve product design and adjust marketing or management strategies.

This study proposes a novel approach to disclose the issue of information imbalance between supply side and demand side and therefore to discover consumer attention from the perspective of design topics. In addition, guidelines for applying the proposed approach for fast-fashion marketing and management are presented.

The aim of this study is to empirically identify crucial dimensions of security management in the container shipping sector in Taiwan and assess their impacts on security performance.

Data for this study were collected by questionnaire survey. An exploratory factor analysis was performed to identify crucial security management dimensions in the container shipping sector. Multiple regression analysis was then performed to examine the effect of security management on the security performance.

Four crucial security management dimensions were identified: facility and cargo management; accident prevention and processing; information management; and partner relationship management. Multiple regression analysis revealed that information management and partner relationship management had significant positive effects on safety performance, whereas partner relationship management had a significant positive effect on customs clearance performance.

This study primarily focuses on the effect of security management on security performance. Future research could identify the drivers and barriers to comply with supply chain security initiatives.

Container shipping firms can improve safety and customs clearance performance by focusing security management efforts on facility and cargo management, accident prevention and processing, information management, and partner relationship management.

Government administrators or other authorities may want to consider using crucial container shipping security management dimensions as criteria for assessing security performance in container shipping firms.

This study presented is the first to assess the effect of security management on security performance in the container shipping sector. Particularly, partner relationship management is found to be the key dimension for supply chain security success.

The basis of human creation lays the foundation for altruism. Babies, be they human or animal are born helpless. Their very survival depends on the love and affection that are already embedded in the hearts of mothers. No amount of selfish attitude of mothers, not at least from short life span, can help in the growth of their off‐springs. One can argue that it is the self‐interested motive of the parents and most particularly the mothers of getting supports in their old days that drives them to be altruistic rather than selfish. Being altruistic means undertaking a lot of sacrifice in terms of personal pleasure and happiness merely for seeing pleasure and happiness in others regardless of any human bondage. An egoistic person, on the other hand, would never care for others. Personal level satisfaction only dominates the mind of an extremely egoistic or self‐centered man.

The characteristics of spherical robots, such as under-drive, non-holonomic constraints and strong coupling, make it difficult to establish its motion control model accurately. To improve the anti-interference performance of spherical robots in practical engineering, this paper proposes a spherical robot motion controller based on auto-disturbance rejection control (ADRC) with parameter tuning.

This paper considers the influences of the spherical shell, internal frame and pendulum on the movement of the spherical robot during the rotation to establish the multi-body dynamics model of the XK-I spherical robot. Due to the serious coupling problem of the dynamic model, the motion control state equation is constructed using linearization and decoupling. The XK-I spherical robot PSO-ADRC motion controller with parameter tuning function is designed by combining the state equation with the particle swarm optimization (PSO) algorithm. Finally, experiments are performed to evaluate the feasibility of PSO-ADRC in an actual case compared to ADRC, PSO-PID and PID.

By analyzing the required time to reach the expected value, the control stability and the fluctuation range of the standard deviation after reaching the expected value, the superiority of PSO-ADRC to ADRC, PSO-PID and PID is demonstrated in terms of the speed and anti-interference ability.

The proposed method can be applied to the robot control field.

A parameter-tuning method for auto-disturbance-rejection motion control of the spherical robot is proposed. According to the experimental results, the anti-interference ability of the spherical robot moving on uneven ground is improved. Therefore, it provides a foundation for the autonomous environmental monitoring of the spherical robot equipped with sensors.

This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity.

Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples.

This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples.

This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.

This paper aims to identify how cute packaging design elements can influence young adult purchases of unfamiliar products, especially the perceived old-fashioned ones.

Two studies were conducted systematically with 240 young adults. The first study manipulated product characters, fonts, colors and storytelling styles to determine the cutest packaging elements. Packaging samples containing the cutest elements from Study 1 were tested for their effect on purchase intention in Study 2, moderated by product familiarity.

Anthropomorphized product characters, curvy, handwritten-like fonts, a mixture of colors and superhero story-like product information were considered the whimsically cutest packaging elements by young adults. Whimsically cute packaging design can bridge consumer product unfamiliarity and generate higher purchase intention.

Whimsically cute packaging design could be a promising alternative for marketers promoting unfamiliar products to young adult consumers.

This study's findings complement existing literature on cute packaging design, whimsical cuteness and extrinsic cue utilization theory.

In response to the COVID-19 pandemic, many employees had to switch to remote work. While some adjusted successfully to this transition, others have struggled. Leveraging information systems (IS) to adjust to major exogenous shocks is called digital resilience. The purpose of this paper is to understand what we can learn about employees' digital resilience from externally enforced transitions to remote work.

As digital resilience is challenging to measure, this study uses an embedded mixed methods approach. The authors conducted a qualitative analysis of 40 employees' statements on their remote work experience during the first six months of the pandemic and complemented these findings with scale-based digital resilience scores.

The authors find that employees' digital resilience largely depends on the amount of technical equipment and support they receive from their organizations as well as their ability and willingness to learn how to adequately use and communicate through information and communication technologies. Being self-disciplined and self-responsible positively affects digital resilience, while social isolation threatens it. Organizations can foster digital resilience building by encouraging digital networking, building a digital culture and netiquette, and treating digital resilience as a sociotechnical phenomenon.

This is one of the first empirical studies of digital resilience on a human level. It sheds light on the missing link between IS-enabled resilience and transitions to remote work. Specifically, it provides original insights into its development and manifestation in a remote work context during the COVID-19 pandemic. For researchers, it provides novel guidance on choosing appropriate measurement instruments to capture digital resilience.