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Silence is a commonly seen phenomenon at the workplace. However, little is known about the cause and effect of leader silence. Drawing on the affective events theory, we develop a moderated mediation model to examine the effect of subordinates’ creative deviance on leader's authoritative silence and test the moderating effect of subordinates’ political skills.

Our research adopts a novel bottom-up perspective to investigate the subordinates’ influence on leader silence. A two-wave survey study involving 196 corporate team leaders in China was employed.

We found that leader’s workplace anxiety mediated the relationship between subordinates' creative deviance and leader's authoritative silence and subordinates’ political skills moderated the mediating effect.

Our research contributes to the leader silence literature in three folds. First, we employ the AET framework to study leader silence from the emotional perspective. Second, this research adopts a bottom-up angle to reveal the influence of subordinates’ behavior on leader silence. Third, the political skills lens offers novel explanation of why the anxious emotions triggered by followers’ creative deviance vary among leaders.

Sustainable urban rail transit requires noise barriers. However, these barriers’ durability varies due to the differing aerodynamic impacts they experience. The purpose of this paper is to investigate the aerodynamic discrepancies of trains when they meet within two types of rectangular noise barriers: fully enclosed (FERNB) and semi-enclosed with vertical plates (SERNBVB). The research also considers the sensitivity of the scale ratio in these scenarios.

A 1:16 scaled moving model test analyzed spatiotemporal patterns and discrepancies in aerodynamic pressures during train meetings. Three-dimensional computational fluid dynamics models, with scale ratios of 1:1, 1:8 and 1:16, used the improved delayed detached eddy simulation turbulence model and slip grid technique. Comparing scale ratios on aerodynamic pressure discrepancies between the two types of noise barriers and revealing the flow field mechanism were done. The goal is to establish the relationship between aerodynamic pressure at scale and in full scale.

The aerodynamic pressure on SERNBVB is influenced by the train’s head and tail waves, whereas for FERNB, it is affected by pressure wave and head-tail waves. Notably, SERNBVB's aerodynamic pressure is more sensitive to changes in scale ratio. As the scale ratio decreases, the aerodynamic pressure on the noise barrier gradually increases.

A train-meeting moving model test is conducted within the noise barrier. Comparison of aerodynamic discrepancies during train meets between two types of rectangular noise barriers and the relationship between the scale and the full scale are established considering the modeling scale ratio.

While the usage of digital technology can bring many operational improvements for firms, it is unclear whether it can effectively improve firm resilience to deal with supply chain disruptions caused by emergencies such as COVID-19. From a dynamic capability perspective, this study aims to investigate how digital technology usage can improve firm resilience in a rapidly changing and turbulent environment.

Based on the survey sample of 237 Chinese firms, the stepwise regression approach was used to examine the proposed research hypotheses.

The empirical evidence shows that digital technology usage has a U-shaped effect on firm resilience, and that effect is fully achieved by first affecting market acuity and then promoting resource reconfiguration. Moreover, the authors further found that the U-shaped association between digital technology usage and firm resilience is derived from the U-shaped association between digital technology usage and market acuity.

This study enriches the resilience literature by revealing the mechanism of digital technology usage’s effects rather than focusing on the role of specific digital technologies. This study also provides guidance for firms to develop effective digital technology usage strategies.

The purpose of this study was to examine sensory attributes, physiochemical characteristics and consumer preference of drop sugar cookies prepared using high-amylose maize resistant starch (HAMRS) as a replacement for 10%, 20% and 30% of all-purpose (AP) flour as compared to a control made with 100% AP flour.

A balanced complete block experimental design was used to evaluate the eating quality of the resistant starch enriched cookies using a consumer panel. Consumer preference for the appearance, flavor, texture, moistness and overall acceptability of cookies was assessed. Diameter, height, spread ratio, hardness, moisture, pH, density, surface color and nutrient composition of cookies were analyzed.

Compared with the control cookies, the HAMRS cookies had lower diameters, higher, heights, reduced spreads, reduced % moisture losses and lower densities (p < 0.001). TA.XT Plus Texture Analyzer showed the HAMRS cookies had a softer texture than the control cookies (p < 0.0001). Evaluation of surface color showed no significant difference in lightness between the control and the HAMRS cookies. The HAMRS cookies were preferred over the control for appearance, texture and moistness in sensory evaluation with 42.5% of panelists choosing the 20% HAMRS replaced cookies as their overall preference. The 20% and 30% HAMRS replaced cookies qualify to be labeled as a “good source” and “excellent source” of fiber, respectively.

This data demonstrates that replacement of up to 30% of AP flour with HAMRS improves eating quality and dietary fiber content of sugar cookies. Our results show that HAMRS has good potential for developing high fiber cookies with minimal adverse impact on physical characteristics and notable improvements in sensory attributes and nutritional value.

To the best of the authors’ knowledge, this is the first study that has reported on the functionality, consumer preference and nutritional value of cookies enriched with a HAMRS that is available to consumers in the form of flour.

This paper aims to propose an efficient and accurate method to analyse the transient heat conduction in a periodic structure with moving heat sources.

The moving heat source is modelled as a localised Gaussian distribution in space. Based on the spatial distribution, the physical feature of transient heat conduction and the periodic property of structure, a special feature of temperature responses caused by the moving heat source is illustrated. Then, combined with the superposition principle of linear system, within a small time-step, computation of results corresponding to the whole structure excited by the Gaussian heat source is transformed into that of some small-scale structures. Lastly, the precise integration method (PIM) is used to solve the temperature responses of each small-scale structure efficiently and accurately.

Within a reasonable time-step, the heat source applied on a unit cell can only cause the temperature responses of a limited number of adjacent unit cells. According to the above feature and the periodic property of a structure, the contributions caused by the moving heat source for the most of time-steps are repeatable, and the temperature responses of the entire periodic structure can be obtained by some small-scale structures.

A novel numerical method is proposed for analysing moving heat source problems, and the numerical examples demonstrate that the proposed method is much more efficient than the traditional methods, even for larger-scale problems and multiple moving heat source problems.

Proposing a new type of water-lubricated thrust bearing meets the load-bearing requirements of high-power shaft-less rim driven thrusters.

The designs were tested by establishing a bearing thermal-fluid-magnetic comprehensive simulation model and developing bearing fluid film force and magnetic simulation. Lubrication performance tests were carried out on the bearing test rig.

The Halbach array of magnet blocks is able to reach the maximum magnetic force. The material of sheath can help increase the magnetism. The magnetism is able to reduce wear during low-speed and the start-stop phase, while the eddy current loss at high speeds will lead to a decrease in magnetic force. The experiment found that the bearing was more stable at low speeds and would not demagnetize due to the temperature rise, but it is necessary to pay attention to the running stability at high speeds to prevent rubbing and impact.

An innovative combination of hydrodynamic pressure and permanent magnetic repulsion was observed to form a magnetic-liquid double suspension bearing with large bearing capacity.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2020-0295

This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO₂ and its radiative cooling effect on firefighting clothing without environmental pollution.

SA/SiO₂ aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple.

When the addition of SiO₂ is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO₂ aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test.

SA/SiO₂ aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling.

This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters.

SA/SiO₂ aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply.

The purpose of this paper was prepared a Ni-based superhydrophobic coating on the surface of copper to enhence its corrosion resistance. The superhydrophobic coating (SHPC) has proven to be an effective surface treatment in corrosion protection. In this paper, a Ni-based SHPC was prepared on the surface of copper (Cu) to enhance its corrosion resistance.

The coating was prepared through a two-step electrodeposition process. The first step involves the formation of a micro-nano structure Ni layer formed by an electrodeposition process. Subsequently, the polysiloxane layer was deposited on the Ni surface to create an SHPC. The morphology, composition, structure, wettability and corrosion resistance of the coating were characterized and discussed.

The results show that the water contact angle of the as-prepared coating reaches 155.5°±1.0°. The corrosion current density (i_corr = 3.90 × 10⁻⁹ A·cm⁻²) decreased by three orders of magnitude compared to the substrate, whereas |Z|_{f = 0.01 Hz} (2.40 × 10⁶ Ω·cm²) increased by three orders of magnitude. It indicated that the prepared coating has excellent superhydrophobicity and high corrosion resistance, which can provide better protection for the substrate.

The prepared coating provides long-lasting protection for Cu and other metals and offers valuable data for developing SHPCs.

Through the scientific and reasonable evaluation of the site selection of the emergency material reserve, the optimal site selection scheme is found, which provides reference for the future emergency decision-making research.

In this paper, we have chosen three primary indicators and twelve secondary indicators to construct an assessment framework for the determination of suitable locations for storing emergency material reserves. By mean of the improved entropy weight-order relationship weight determination method, the evaluation model of kullback leibler-technique for order preference by similarity to an ideal solution (KL-TOPSIS) emergency material reserve location based on relative entropy is established. On this basis, 10 regional storage sites in Beijing are selected for evaluation.

The results show that the evaluation model of the location of emergency material reserve not only respects the objective knowledge, but also considers the subjective information of the experts, which makes the ranking result of the location of the emergency material reserve more accurate and reliable.

Firstly, the modification factor is added to the calculation formula of traditional entropy weight method to complete the improvement of entropy weight method. Secondly, the order relation analysis method is used to assign subjective weights to the indicators. The principle of minimum information entropy is introduced to determine the comprehensive weight of the index. Finally, KL distance and TOPSIS method are combined to determine the relative entropy and proximity degree of alternative solutions and positive and negative ideal solutions, and the scientific and effective of the method is proved by case study.

This paper aims to examine patient admission control (AC) policies aimed at reducing patient waiting times during a pandemic. Unlike previous studies that focused on AC within a single hospital, this research seeks to minimize waiting times across multiple hospitals. The primary objective is to ensure that patients are admitted to the most appropriate hospital to reduce congestion during a pandemic.

This paper proposes two stochastic dynamic programming (DP) models. The first model treats the number of available beds as a fixed parameter, while the second model considers the number of beds as a decision variable. In the first model, the main decision is determining which hospital a pandemic patient should be assigned to. Bed allocation is not addressed in this model. The rationale for presenting two models is based on the dynamic nature of hospital resource allocation. In some situations, hospital administrators must decide how to configure beds between pandemic and nonpandemic wards. In other scenarios, bed allocation is predetermined and remains constant throughout the pandemic. DP algorithms are used to precisely solve small-scale instances of the problem and generate policies for patient assignment. These policies are then evaluated against alternative heuristic policies using larger-scale problem instances and simulation tools.

Simulation results reveal that implementing an AC unit and adopting an appropriate patient allocation policy can reduce average patient waiting times by approximately 50%. Moreover, when equity is a consideration (when the objectives are in the form of min-max), the policies derived from the DP approach outperform heuristic policies. However, some heuristic policies are more effective when equity is not a primary concern.

The findings of this research can assist health-care managers in making informed decisions by highlighting the implications and performance of various strategies.