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This study aims to assess the effects of risk perception and management subject satisfaction on consumers' online meal food safety self-protection behavior during the COVID-19 pandemic.

This study uses 742 questionnaires collected via a two-stage online survey conducted during the COVID-19 pandemic, between December 2021 and January 2022. The entropy method, descriptive statistics, ordered logit model, stepwise regression models, interaction terms and decentralization method were used in the quantitative analysis. Respondents’ written responses to self-protection behavior were categorized into five groups.

Less than half of consumers were aware that online food products carry the risk of SARS-COV-2 (44.48%). Between 30 and 40% of consumers took insufficient or no self-protection measures. Risk perception significantly and positively affected self-protection behavior during the COVID-19 pandemic. Consumers' management subject satisfaction has a positive moderating effect on risk perception, with the moderating effect of the satisfaction of online retailers being significant at the 5% level. Risk perception significantly and positively influences consumer self-protection behavior in provinces not affected by the pandemic.

The findings stress the benefits of synergistic interventions by consumers and management subject to food safety measures and the inclusion of tailored interventions during events threatening public health to effectively address food safety. The study offers valuable insights contributing to the improvement of public health outcomes, customer trust and service quality within the online food delivery industry.

The representation of Heterogeneous Object (HO) is divided into two categories: Data model (DM) and material evaluation paradigm (MEP). A hybrid methodology with geometry model and volumetric dataset to represent heterogeneous properties is proposed in this paper. Geometry model of an object can guarantee the accuracy of the final HO slices; and volumetric dataset lends the flexible manipulability and other advantages to HO representation. Two MEPs, namely distance field (DF) based and Fixed Reference Features & Active Grading Source(s) (FRF&AGS) are presented to facilitate the process of HO representation according to the designer)s input parameters. The DM can be modified interactively with users until the final satisfactory result is obtained. In this paper, a scheme of HO slicing is described. In this method, we utilize the slices contour of geometrical model as constraint to reconstruct the HO slices, which can theoretically achieve the same accuracy with the geometrical shape. Some examples of Heterogeneous object represented with our scheme are provided.

The purpose of this paper is to characterize and understand the effects of polymer binder, thixotropic agent, solvent and organic medium content on the rheological properties of silver pastes for screen printing front electrode films of solar cells.

Dispersions of silver particles (surface modified with oleic acid) in ethyl cellulose (EC) polymer solutions with and without thixotropic agent were prepared, and yield stress values were measured by setting shear stress to characterize the inter-particle interaction strength of pastes. Steady-state flow, three interval thixotropy shear test and oscillatory measurements were conducted to study the effect of EC polymer and thixotropic agent on viscosity, structure rebuilding and viscoelastic properties of electrode pastes. The effect of solvent was studied by investigating the steady viscosity of cellulose acetate butyrate (CAB) polymer solutions and Ag dispersions.

Weak flocculation network of silver particles was produced because of depletion flocculation. Besides the interaction between thixotropic agent micelles, EC polymer also has a significant interaction with thixotropic agent. Merely increasing EC polymer or thixotropic agent content is not the best way to prevent the layer printed from laying down. The effect of solvent on the viscosity of paste is mainly attributed to the difference of hydromechanics radius and configuration of CAB polymer in solvents. With the increase of organic medium content, the properties of electrode pastes were converted from rigidity to flexibility.

It is still a challenge to obtain high-quality front electrode films for crystalline silicon solar cells by screen printing, because of the difficulty in reducing shadowing losses while ensuring a low series resistance and high filling factor. The paste rheological properties are the key properties related to the paste’s passing ability through the meshes and resistance of paste spreading on the substrate. Organic medium as an important component of the paste is acknowledged to be used to tailor the paste’s rheological properties and have a great role in screen printing.

To construct a scientific and reasonable indicator system, it is necessary to design a set of standardized indicator primary selection and optimization inspection process. The purpose of this paper is to provide theoretical guidance and reference standards for the indicator system design process, laying a solid foundation for the application of the indicator system, by systematically exploring the expert evaluation method to optimize the index system to enhance its credibility and reliability, to improve its resolution and accuracy and reduce its objectivity and randomness.

The paper is based on system theory and statistics, and it designs the main line of “relevant theoretical analysis – identification of indicators – expert assignment and quality inspection” to achieve the design and optimization of the indicator system. First, the theoretical basis analysis, relevant factor analysis and physical process description are used to clarify the comprehensive evaluation problem and the correlation mechanism. Second, the system structure analysis, hierarchical decomposition and indicator set identification are used to complete the initial establishment of the indicator system. Third, based on expert assignment method, such as Delphi assignments, statistical analysis, t-test and non-parametric test are used to complete the expert assignment quality diagnosis of a single index, the reliability and validity test is used to perform single-index assignment correction and consistency test is used for KENDALL coordination coefficient and F-test multi-indicator expert assignment quality diagnosis.

Compared with the traditional index system construction method, the optimization process used in the study standardizes the process of index establishment, reduces subjectivity and randomness, and enhances objectivity and scientificity.

The innovation point and value of the paper are embodied in three aspects. First, the system design process of the combined indicator system, the multi-dimensional index screening and system optimization are carried out to ensure that the index system is scientific, reasonable and comprehensive. Second, the experts’ background is comprehensively evaluated. The objectivity and reliability of experts’ assignment are analyzed and improved on the basis of traditional methods. Third, aim at the quality of expert assignment, conduct t-test, non-parametric test of single index, and multi-optimal test of coordination and importance of multiple indicators, enhance experts the practicality of assignment and ensures the quality of expert assignment.

The diagnosis and prediction methods used for estimating the health conditions of the bearing are of great significance in modern petrochemical industries. This paper aims to discuss the accuracy and stability of improved empirical mode decomposition (EMD) algorithm in bearing fault diagnosis.

This paper adopts the improved adaptive complementary ensemble empirical mode decomposition (ICEEMD) to process the nonlinear and nonstationary signals. Two data sets including a multistage centrifugal fan data set from the laboratory and a motor bearing data set from the Case Western Reserve University are used to perform experiments. Furthermore, the proposed fault diagnosis method, combined with intelligent methods, is evaluated by using two data sets. The proposed method achieved accuracies of 99.62% and 99.17%. Through the experiment of two data, it can be seen that the proposed algorithm has excellent performance in the accuracy and stability of diagnosis.

According to the review papers, as one of the effective decomposition methods to deal with nonlinear nonstationary signals, the method based on EMD has been widely used in bearing fault diagnosis. However, EMD is often used to figure out the nonlinear nonstationarity of fault data, but the traditional EMD is prone to modal confusion, and the white noise in signal reconstruction is difficult to eliminate.

In this paper only the top three optimal intrinsic mode functions (IMFs) are selected, but IMFs with less correlation cannot completely deny their value. Considering the actual working conditions of petrochemical units, the feasibility of this method in compound fault diagnosis needs to be studied.

Different from traditional methods, ICEEMD not only does not need human intervention and setting but also improves the extraction efficiency of feature information. Then, it is combined with a data-driven approach to complete the data preprocessing, and further carries out the fault identification and classification with the optimized convolutional neural network.

This study aims to examine the cutting performance of a coated carbide tool during the boring of 1Cr17Ni2 martensitic stainless steel, with a focus on how the tool’s structural parameters, particularly the nose radius, affect the wear patterns, wear volume and lifetime of the cutting tool, and related mechanisms.

A full factorial boring experiment with three factors at two levels was conducted to analyze systematically the impact of cutting parameters on the tool wear behavior. The evolution of tool wear over the machining time was recorded, and the influences of the cutting parameters and nose radius on wear behavior of the tool were examined.

The results show that higher cutting parameters lead to significant wear or plastic deformation at the tool nose. When the cutting depth is less than the nose radius, the tool wear tends to be minimized. Larger nose radius tools have weaker chip-breaking but greater strength and wear resistance. Higher cutting parameters reduce wear for the tools with larger nose radius, maintaining their integrity. Wear mechanisms are primarily abrasive, adhesive and diffusion wear. Furthermore, the full-factorial analysis of variance revealed that for the tool with r_ε = 0.4 mm and 0.8 mm, the factors contributing the most to tool wear were cutting speed (38.76%) and cutting depth (86.43%), respectively.

This study is of great significance for selection of cutting tools and cutting parameters for boring 1Cr17Ni2 martensitic stainless-steel parts.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2024-0266/

The purpose of this paper is to understand the root cause of a large number of quality problems in the current Chinese construction market.

Information economics theory is used to analyze the cause of construction quality problems related to the specific case of the Wenchuan earthquake of China.

The single low price competition in the construction tender market leads to the serious adverse selection and moral hazard behavior of bidding firms. The main solution to this problem is the introduction and improvement of an independent inspection/supervision mechanism.

The paper systematically analyzes the evaluation method of the lowest price winning bidding policy, which is the fundamental cause of adverse selection and moral hazard problems in the Chinese construction market.

This paper aims to draw upon motivated information processing theory to examine the sequential mediating roles of perspective taking and boundary spanning between transformational leadership and the creative performance of knowledge workers.

The study was carried out on a sample, including a dyad of 398 knowledge workers and their immediate supervisors in four research institutes in southwest China. The authors tested the theoretical model using structural equation modeling (SEM) and Mplus 7.0 software.

The results support the mediation model in which perspective taking was found to significantly and positively mediate the relationship between transformational leadership and boundary spanning. Boundary spanning was found to significantly and positively mediate the relationship between perspective taking and creative performance. Moreover, both perspective taking and boundary spanning were found to mediate the relationship between transformational leadership and creative performance.

The study findings imply that the transformational leadership behaviors of managers or supervisors nurture knowledge workers' perspective taking and their boundary spanning activities leading to creative performance.

The findings contribute new knowledge to the relationship between transformational leadership and creative performance by uncovering the causal chain of a cognitive mechanism (perspective taking) with a behavioral mechanism (boundary spanning).

The purpose of this paper is to report upon high power, internally matched GaN high electron mobility transistors (HEMTs) at Ku band with 1.5 GHz bandwidth, which employ a simple and cost‐effective lossless compensated matching technique.

Two 4 mm gate periphery GaN HEMTs are parallel combined and internally matched with multi‐section reactive impedance transformers at the input and output networks. The output matching network is designed at the upper frequency of the design band for a flat power of the circuit, while the input matching network is designed at the upper frequency for a flat gain.

With the reactively compensated matching technique, the internally matched GaN HEMTs exhibit a flat saturated output power of 43.2+0.7 dBm and an average power added efficiency of 15 per cent over 12 to 13.5 GHz.

This paper provides useful information for the internally matched GaN HEMTs.

The purpose of this paper is to examine the effects of perceived benefits, i.e. utilitarian value, hedonic value and social value, as well as perceived risk, on purchase intention in social commerce context.

To cast light on the factors motivating users’ intention to purchase in the context of social commerce, data of 277 users of social commerce in China were collected via an online survey.

Results show that satisfaction significantly and positively affects users’ purchase intention in social commerce context. In addition, utilitarian, hedonic and social values have significant and positive impacts on satisfaction and purchase intention; and utilitarian value is found to be the most salient factor influencing purchase intention, while hedonic value has the greatest effect on satisfaction. Moreover, perceived risk significantly and negatively affects satisfaction.

Extant research on social commerce has mainly focused on investigating how the general perceived value affects user behavior, but has less considered different dimensions of perceived value. Moreover, prior studies have explored the roles of utilitarian and hedonic values on user behavior; however, there is a lack of research on the effect of social value. The current study attempts to fill these research gaps.