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The purpose of this paper is to propose and optimize plastic optical fiber (POF) probe with macro-bending biconical tapered structure for the relative humidity (RH) sensing.

In this study, the principle is the evanescent wave power modulated by the ambient humidity. The probe is fabricated by using fused biconical taper and heat-setting method and then coated with a fluorescent moisture-sensitive film.

The probe’s sensing performance can be optimized by changing the probe’s curvature radius, biconical tapered transition length and taper waist diameter. The result shows that the sensitivity of the probe is up to 1.60 and 3.40 mV/ per cent, respectively, at low humidity (10-45 per cent) and high humidity (45-90 per cent). Also, this probe has good linearity, repeatability, photostability and long-term stability.

The proposed probe can improve the sensitivity and linearity of RH sensing without complex devices, which is necessary for mass production, remote measurement and convenient operation.

POF probe with macro-bending biconical tapered structure is investigated in this paper, which is proved to be effective in improving the sensitivity and linearity.

The purpose of this paper is to explore the heterogeneity and correlations of agricultural greenhouse gas (GHG) emissions among provinces in China, and then policy implications are proposed.

After agricultural GHG accounting and a pre-analysis of inter-provincial heterogeneity, improved gravity model and the Social Network Analysis (SNA) methods are introduced to construct the network, being carried out from three aspects of the whole network, individual provincial characteristics and cluster analysis.

(1) There are significant regional variations in agricultural GHG scale among provinces owing to the layout of agricultural production, and the temporal trends show that the direction and speed of agricultural GHG scale change vary among provinces; (2) In terms of inter-provincial correlations, there exists a complex spatial network of agricultural GHG among provinces, which tends to be more complex, intensive and stable, while the status of the provinces in the network also has gradually become more balanced. All provinces played their respective roles in the four clusters of the network with agricultural layout and comparative advantages, and the distribution has continuously optimized.

The inter-provincial network characteristics of agricultural GHG emissions and its evolution have practical implications for differentiated and coordinated agricultural GHG reduction policies at the provincial levels.

This paper innovatively study inter-provincial agricultural GHG correlations in China with the SNA methods used to study economic and social connections in the past. There is some originality in the introduction of network theory and application of the SNA methods, which can provide some reference for researches in similar fields.

Based on the perspective of knowledge management, this study aims to discuss how to build cross-city emergency management collaboration mechanism in major emergencies and explore the important role of knowledge management in emergency management collaboration.

Based on the theoretical analysis of knowledge management and the typical case study of cross-city emergency management collaborative rescue, this study provides an in-depth analysis of how these cities achieve high emergency management performance through multidimensional and multilevel knowledge collaboration, thus revealing the mechanism of knowledge transfer, integration and sharing in achieving high emergency management performance.

Through analyzing typical cases, this study finds that building a smooth mechanism for multichannel emergency rescue information can promote the diversification of knowledge transfer methods, building a platform-based integration mechanism for emergency rescue information can enhance knowledge integration capabilities and building a linkage mechanism for emergency rescue materials between cities can promote knowledge-sharing level, thereby improving emergency management performance level.

This study has great significance for how to build cross-city emergency management collaboration mechanism in the digital era. In the future, the authors need to further discuss the following two aspects in depth: research on the impact of cross-city emergency management collaboration mechanism on improving the knowledge management capabilities of government emergency management departments; and research on the impact mechanism of knowledge management capabilities on city resilience.

Through case analysis of cross-city emergency management collaborative rescue for major emergencies in China in recent years, this study proposes three specific strategies for cross-city emergency management (smooth, integration and linkage mechanisms) and reveals that these three strategies are essentially aimed at improving the government’s knowledge management level.

Using signaling theory, the overarching purpose of this study is to provide an insight into how age-inclusive HR practices (AIHRP) influence older workers' voice behavior through job crafting toward strengths (JCS) and how negative age-based metastereotypes (NABM) moderate these relationships.

Using time-lagged data were obtained from 321 Chinese older workers. PROCESS MACRO and Bootstrapping were used to test theoretical hypotheses.

Our results revealed the positive effects of AIHRP on both JCS and voice behavior, and the positive effect of JCS on voice behavior, as well as the mediating role of JCS in the relationship between AIHRP and voice behavior. Besides, results also found that NABM negatively moderate the effect of AIHRP on voice behavior, and the effect of AIHRP on JCS. Additionally, significant moderated mediation effect indicates that the indirect effect of AIHRP on voice via JCS will be weaker for employees with higher NABM.

First, we take the lead in linking AIHRP and employees' voice behavior. This complements voice literature by identifying an important new factor in motivating older workers' voice behavior. Second, by exploring the mediating role of JCS, we reveal the “black box” of how AIHRP affect older workers' voice behavior. Third, this study responds to the call for more studies exploring the boundary conditions of AIHRP and expands the theoretical research framework of the relationship between AIHRP, JCS and voice, deepens our understanding of the mechanism of voice behavior.

Our findings have several practical implications. First, the leadership personnel throughout the firm should be conscious of the crucial role of AIHRP. Second, managers should provide older workers with opportunities to craft their jobs to use their strengths and achieve a better person-job fit, which will result in a series of positive outcomes. Third, organizations should blur intergenerational boundaries within the organization and provide older workers with mentoring opportunities to motivate their voice.

Our findings have some social implications. Firstly, the results of this study are beneficial in demonstrating to society that older workers still have significant strengths and value. With reasonable methods, older workers can continue to contribute to the development of organizations and society, which in turn is conducive to changing society's perceived bias toward older workers, reducing age discrimination and promoting social harmony. Secondly, this study provides theoretical guidance for organizations and society to manage older workers, which is conducive to alleviating social problems such as youth labor shortage and increased burden of retirement.

This study is innovative as it first explores the influence, mechanism and boundary conditions of AIHRP on older workers' voice behavior, which not only deepens our understanding of older workers voice, but also enriches the research on AIHRP and JCS.

The purpose of this paper is to study the impact of political connections and institutional environment differences on private enterprises' acquiring bank loans, and to analyze the governance effect of bank debts and its impact on firm value.

Choosing private listed enterprises in China as samples, this study builds equation models and uses the three‐stage least squares estimation method to estimate these models.

The results show that: political connections influence lending policies of banks; the politically connected private enterprises could acquire more loans from banks. In poorer institutional environment, political connections can help private enterprises to acquire more bank loans; building political connections is an informal substitute mechanism for private enterprises to overcome the drawbacks of market institutions. The bank loans have governance effects on politically connected private enterprises and can increase firm value; the allocation of bank loans through political connections is efficient.

This study provides a meaningful perspective for understanding the impact of political connections on firm value and allocation of social resources.

Developing multigenerational products through iteration helps enterprises cope with environmental uncertainty and maintain lasting competitive advantages in a globally competitive environment. From the knowledge integration perspective, this study aims explore how enterprises achieve multigenerational product innovation.

An exploratory case study design is used to explore the multigenerational product innovation process.

This study proposes a model of the multigenerational product innovation process and shows that knowledge integration includes two important parts: the internalization of external knowledge and intergenerational knowledge integration. This study further conclude that multigenerational innovation has three main channels: rapid iteration, continuous reflection and coordination.

First, this study presents a theoretical model of the process of multigenerational product innovation, including triggers, knowledge integration, learning systems and outcomes, and further enhances our understanding from product innovation to multigenerational product innovation. Second, this study contributes to the literature on the multigenerational product innovation process by revealing the knowledge integration process of the internalization of external knowledge and intergenerational knowledge integration.

At present, electrical heating clothing is widely used to keep ourselves warm at low temperature. The purpose of this paper is to explore the heat transfer performance of electrical heating fabric and the thermal comfort of human skin at low temperature.

The combined model of skin-electrical heating fabric system was established to simulate human skin tissue wearing electrical heating clothing. A series of simulation experiments are designed on the basis of verifying the effectiveness of the combined model. The temperature distribution inside the combined model and on the skin surface under different heating powers is simulated and analyzed. At the same time, the influence of ambient temperature on the thermal performance of electrical heating fabric was explored.

The skin model with blood vessels reflected the temperature change of human skin wearing electrical heating clothing. The higher the heating power of the electrical heating fabric was, the greater the temperature of the skin surface changed, the faster the temperature rose and the longer the time required to reach the stable state would be. After the heating element was electrified, it had the greatest effect on the average temperature of the epidermis and dermis, had smaller effect on the average temperature of subcutaneous layer and had little effect on the temperature of blood vessels. When the heating power was the same, the higher the ambient temperature was, the more obvious the heating effect of electrical heating fabric was. Electrical heating fabrics with different heating powers were suitable for different ambient temperature ranges.

A reasonable and effective evaluation method for the thermal comfort of electrical heating fabric was provided by establishing the skin model and combined model of the skin-electrical heating fabric system. It provides a reference for the design and application of electrical heating clothing.

The purpose of this paper is to investigate the dynamic forming process of the micro dent fabricated by laser shock processing on 2024-T3 aluminum alloy. The effect of laser pluse energy on the deformation of micro dent was also discussed in detail.

It uses finite element analysis method and the corresponding laser shocking experiment.

The results demonstrate that the dynamic formation process of micro dent lasts longer in comparison with the shock wave loading time, and the depths of micro dents increase with the increasing laser energy. In addition, laser shocking with higher energy can result in more obvious pileup occurred at the outer edge of micro dent.

Surface micro dents can serve as fluid reservoirs and traps of the wear debris, which can decrease the effects of the wear and friction in rolling and sliding interfaces. The investigations can not only be propitious to comprehensively understand the forming mechanism of laser-shocked dent, but also be beneficial to get sight into the residual stress field induced by laser shocking.

The purpose of this paper is to investigate how supplier concentration influences a buyer firm's R&D intensity. This study proposes a mediation and moderation model to test this relationship in the Chinese household appliance industry. Specifically, this study tests the mediation effect of operational slack on the relationship between supplier concentration and R&D intensity and the moderation effect of financial constraints on this relationship.

Drawing upon real options theory and resource dependence theory, the proposed relationships are tested with the Chinese household appliance market using financial data from listed companies over a ten-year span from 2012 to 2021. Fixed effects (within-group) panel regression models are used to test the hypotheses. In addition, the authors use the bias-corrected bootstrap method to test the mediation effect.

The authors find that supplier concentration negatively affects a buyer firm's R&D intensity and that internal operational slack mediates this relationship. Interestingly, financial constraints from the external financing organization weaken the negative relationship between the buyer firm's supplier concentration and R&D intensity.

Based on the argument of real options theory and resource dependence theory, this study provides novel insights into the issue of how concentration on several major suppliers may reduce buyer firms' R&D intensity. First, this study introduces operational slack as a form of internal uncertainty that mediates the supplier concentration–R&D intensity relationship. Second, this study suggests that the effect of supplier concentration on R&D intensity is contingent upon firms' financial constraints from external financial organizations, disclosing a synergetic interactive effect of supplier concentration and financial constraints on firms' R&D activities. Third, this study is conducted in the unique institutional context of China, providing meaningful insights into the relationship between supplier concentration and R&D intensity.

The heat transfer properties play significant roles in the thermal comfort of the clothing products. The purpose of this paper is to find the relationship between heat transfer properties and fabrics' structure, yarn properties and predict the effective thermal conductivity of single layer woven fabrics by a parametric mathematical model.

First, the weave unit was divided into four types of element regions, including yarn overlap regions, yarn crossing regions, yarn floating regions and pore regions. Second, the number and area proportion of each region were calculated respectively. Some formulas were created to calculate the effective thermal conductivity of each element region based on serial model, parallel model or series–parallel mixing model. Finally, according to the number and area proportion of each region in weave unit, the formulas were established to calculate the fabric overall effective thermal conductivity in thickness direction based on the parallel models.

The influences of yarn spacing, yarn width, fabric thickness, the compressing coefficients of air layers and weave type on the effective thermal conductivity were further discussed respectively. In this model, the relationships between the effective thermal conductivity and each parameter are some polynomial fitting curves with different orders. Weave type affects the change of effective thermal conductivity mainly through the numbers of different elements and their area ratios.

In this model, the formulas were created respectively to calculate the effective thermal conductivity of each element region and whole weave unit. The serial–parallel mixing characteristics of yarn and surrounding air are considered, as well as the compression coefficients of air layers. The results of this study can be further applied to the optimal design of mixture fabrics with different warp and filling yarn densities or different yarn thermal properties.