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The purpose of this paper is to investigate the impact of mechanical vibration on the heat transfer and pressure drop characteristics of semicircular channel printed circuit heat exchangers (PCHEs), while also establishing correlations between vibration parameters and thermal performance.

By combining experimental and numerical simulation methods, the heat transfer coefficient and pressure drop characteristics of supercritical carbon dioxide (S-CO₂) in a semicircular channel with a diameter of 2 mm under vibration conditions were studied. Reinforce the research by conducting computational fluid dynamics studies using ANSYS Fluent 22.0, the experimental results were compared with the numerical simulation results to verify the accuracy of the numerical method.

The use of vibration has the potential to attenuate the degradation of wall heat transfer caused by buoyancy-induced PCHEs on the upward-facing surface. The heat transfer enhancement (HTE) was maximized by an increase of 18.2%, while the pressure drop enhancement (PDE) was elevated by over 25-fold. The capacity to enhance the heat exchange between S-CO₂ and channel walls through increasing vibration intensity is limited, indicating maximum effectiveness in improving thermal performance.

Conducting heat transfer experiments on PCHEs with mechanical vibration enhancement and verifying the accuracy of the vibration numerical model. The relation based on the dimensionless factor is derived. To provide theoretical support for using vibration to enhance the heat transfer capability of PCHEs.

The symmetry error generated in the machining process of herringbone gears will destroy the stability of the transmission system. The purpose of this paper is to establish a symmetry error measurement model of herringbone gear based on spiral measurement method, and to evaluate the transmission accuracy of herringbone gear based on the measured symmetry error.

A symmetry error measurement model of herringbone gear based on spiral measurement method is proposed. The measurement method is verified by three coordinate measuring instrument. The transmission error analysis model of herringbone gear is established. The influence of speed and load on it is analyzed.

At the same speed, when the load increases from 100 N·m to 500 N·m, the transmission error increases and the transmission accuracy of the system decreases. Under the same load, the speed is increased from 100 rpm to 500 rpm, which has little effect on the transmission error.

The measurement method and analysis model used in this paper provide reference value and significance for the measurement and analysis of symmetry error.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2024-0350/

We examine the effectiveness of signaling by disclosing innovation in annual reports in terms of securing R&D subsidies, using a novel text-based measure of firm-level innovation intensity.

The empirical analysis includes regressions with firm and year-fixed effects and an instrumental variable approach. Both mediation and moderation analysis are conducted to identify the plausible channels.

We find that firms are likely to receive research and development (R&D) subsidies if their annual reports contain intensive disclosure of information about innovation. We also identify the site visits by government officials as a plausible channel through which innovation disclosure in annual reports can help firms receive R&D subsidies. Additional analysis shows the main effect of innovation disclosure is especially pronounced in firms with severe information asymmetry and those facing a low-trust environment.

Current studies have shown the effectiveness of signaling in capital markets in terms of securing bank loans and venture capital (Cassar et al., 2015; Hoenig and Henkel, 2015; Connelly et al., 2016; Plummer et al., 2016). It is unclear if such a signaling can attract the attention of government officials. Our results suggest that government officials view annual reports as an important means of mitigating information asymmetry, which in turn helps firms to receive external R&D funding.

This paper aims to explore blockchain integration strategies within a three-level livestock meat supply chain in which consumers have a preference for quality trust in livestock meat products. The paper investigates three questions: First, how does consumers’ preference for quality trust affect blockchain integration and transaction decisions among supply chain participants? Second, under what circumstances will retailers choose to participate in the blockchain? Finally, how can other factors such as blockchain costs and supplier–retailer partnership value affect integration decisions?

This paper formulates a supply chain network equilibrium model and employs the logarithmic-quadratic proximal prediction-correction method to obtain equilibrium decisions. Extensive numerical studies are conducted using a pork supply chain network to analyze the implications of blockchain integration for different supply chain participants.

The results reveal several key insights: First, suppliers’ increased blockchain integration, driven by higher quality trust preference, can negatively affect their profits, particularly, with excessive trust preferences and high blockchain costs. Second, an increase in consumers’ preference for quality trust expands the range of unit operating costs for retailers engaging in blockchain. Finally, the supplier–retailer partnership drives retailer blockchain participation, facilitating enhanced information sharing to benefit the entire supply chain.

This study provides original insights into blockchain integration strategies in an agricultural supply chain through the application of the supply chain network equilibrium model. The investigation of several key factors on equilibrium decisions provides important managerial implications for different supply chain participants to address consumers’ preference for quality trust and enhance overall supply chain performance.

Adopting the context, input, process and product (CIPP) evaluation assessment model, this study aims to achieve three objectives: (1) to identify the characteristics of educational activities conducted by the International Table Tennis Federation (ITTF) museum; (2) to explore the key factors that promote and optimize the educational objectives of the ITTF museum and (3) to develop a framework that attempts to unpack the complex and dynamic processes of activities conducted by the ITTF museum.

A qualitative research using in-depth interviews was conducted to explore the functions and activities of the ITTF museum.

The path of educational activities carried out is expressed in four aspects: (1) educational background including philosophy and purpose, advantages possessed and the learning needs and readiness of the audience; (2) the resource input includes resource allocation, venue structure, funding channels and the basis of activity program design; (3) the educational activity process includes external cooperation and exchange, the specific content of the activity programs, the teaching strategies and methods during the activities and the response to the challenges of the epidemic and (4) the results of the activities include the number of audience and population distribution, evaluation and feedback of the activities, ways and means of promoting the activities and difficulties and challenges faced.

In the follow-up studies, quantitative research can be conducted by developing a questionnaire based on the current study’s findings. Evaluation scales can be set to continue to enrich and improve the uncovered research content, which is conducive to promoting the objectives of the ITTF museum and giving full play to the educational function, thus enriching the research of sports museums.

The contributions of this study are as follows. First, it enriches the application of the CIPP assessment model in the context of sports museums. It helps the ITTP museum better perform its educational function and provides a reference for future activities of sports museums.

This study aims to optimize the preparation conditions and modify the nanofiltration (NF) membranes to prepare high-performance polysulfone/sulfonated polysulfone composite nanofiltration (PSF/SPSF-NF) membranes through interfacial polymerization.

Investigating the impacts of anhydrous piperazine (PIP) concentration, trimesoyl chloride (TMC) concentration and basement membrane type on NF membrane performance, the optimal membrane was prepared. In addition, nano-SiO₂ was added to the active separation layer to modify the NF membranes.

The comprehensive performance of PSF/SPSF-NF membranes was optimized when the concentration of PIP was 0.75 Wt.% and the concentration of TMC was 0.15 Wt.%, at which time the water flux was 66.1 L·m⁻²·h⁻¹ and the retention rate of Na₂SO₄ was 98.1%. The comprehensive performance of polysulfone/sulfonated polysulfone-SiO₂ nanofiltration (PSF/SPSF-SiO₂-NF) membranes was optimized when the blending ratio of nano-SiO₂ to PIP was 2:3, with a pure water flux of 81.9 L·m⁻²·h⁻¹ and a Na₂SO₄ retention rate of 95.9%. Compared to polysulfone nanofiltration (PSF-NF) membranes and PSF/SPSF-NF membranes, NF membranes with nano-SiO₂ increased the flux recovery rate by 22.9% and 8.7%.

PSF/SPSF-SiO2-NF membrane exhibits excellent antifouling properties.

There is currently no literature available on the preparation of NF membranes using polysulfone/sulfonated polysulfone (PSF/SPFS) as a substrate. This provides a method for modifying NF membranes, starting with the modification of the basement membrane and then modifying the active separation layer.