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This paper aims to try to develop new, environmentally friendly and efficient lubricating additives; study the compatibility of carbon-based additives with different base oils [Polyalphaolefin (PAO)-3, PAO-20 and NPE-2]; and explore the lubrication mechanism.

Oleylamine modified carbon nanoparticles (CNPs-OA) were prepared and the dispersion stability of CNPs-OA in PAO-3, PAO-20 and NPE-2 base oils was investigated by transmission electron microscopy, Fourier transform infrared, thermogravimetric analysis, energy dispersive spectroscopy and X-ray photoelectron spectroscopy. Universal Mechanical Tester (UMT) platform was used to carry out experiments on the effects of different additive concentrations on the lubricating properties of base oil.

The mean friction coefficient of PAO-3, PAO-20 and NPE-2 reduced by 32.8%, 10.1% and 11.4% when the adding concentration of CNPs-OA was 1.5, 2.0 and 0.5 Wt.%, respectively. Generally, The CNPs-OA exhibited the best friction-reducing and anti-wear performance in PAO-3.

The agglomeration phenomenon of carbon nanoparticles as lubricating additive was improved by surface modification, and the lubricating effect of carbon nanoparticles in three synthetic aviation lubricating base oils was compared.

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

This study examines the impact of industry-university-research (IUR) cooperation on the financial performance of pharmaceutical enterprises in China. The current literature has primarily focused on the effects of IUR cooperation on innovative performance, often overlooking its financial implications. This research aims to address this gap by analyzing how such collaborations affect financial outcomes.

Using a difference-in-differences (DID) approach, this study analyzes data from publicly listed Chinese pharmaceutical companies between 2011 and 2022. The analysis includes robustness checks and heterogeneity analysis to validate the findings.

Empirical results indicate that IUR cooperation significantly improves the financial performance of pharmaceutical enterprises. Firms engaged in IUR collaborations exhibit a notable improvement in return on assets (ROA) and return on equity (ROE). The research findings confirm that absorptive capacity (internal factors) and the external knowledge resource base (external factors) enhance the positive impact of IUR collaboration on the financial performance of pharmaceutical enterprises. Additionally, the heterogeneity analysis based on regional levels of intellectual property protection demonstrates a stronger positive influence of IUR cooperation on the financial performance of pharmaceutical enterprises in regions with greater levels of intellectual property protection.

This study contributes to the understanding of the financial benefits of IUR cooperation in the biopharmaceutical sector. By highlighting the significance of absorptive capacity, external knowledge resource base and regional intellectual property protection, this study offers valuable insights for policymakers and business leaders aiming to cultivate effective industry–academia collaborations.

The purpose of this paper is to examine the interaction effect of innovative product category and presentation order on consumer consumer’s purchasing intention and the mediating role of perceived novelty and risk perception.

The authors examined the hypotheses in three experiment studies. In Study 1, the authors primed innovative product category and presentation order on consumer consumer’s purchasing intention. In Study 2, the authors measured the mediating role of perceived novelty and risk perception. In Study 3, they validated the moderating effect of picture and text consistency on the improvement of purchase preference.

The results reveal that RNP/INP and presentation order (from whole to part/from part to whole) could enhance consumers’ purchase intention and verify the mediating role of perceived novelty and risk perception, based on which a complete internal mechanism model is constructed. The third experiment shows the moderating effect of picture and text consistency on the improvement of purchase preference by matching the category and presentation order of innovative products.

Prior literature on the thinking mode of holistic and partial processing has been mostly applied to the cognitive field of reading and text labeling. In this study, using the holistic (local) processing thinking model and anchoring theory, eye movement experiments and situational experiments, the audience’s analysis framework of information processing mechanism is constructed. The unique phenomenon of product category and overall (local) presentation order coexisting in innovative product advertisement is considered comprehensively.

Relying on a multilevel approach, this paper investigates the day-to-day variations in family-supportive supervisor behaviors influencing subordinates' job stress, as well as the mediating role of positive emotions and the moderating role of ethical leadership.

Using the experience-sampling methodology, the study collected the data from 137 civil servants in China who responded to one daily survey for 10 working days.

With a total of 1,370 surveys, results supported the hypothesized model linking daily family-supportive supervisor behaviors to daily job stress via subordinates' daily positive emotions. In addition, the study found a moderating effect for ethical leadership positively in the indirect relationship between family-supportive supervisor behaviors and job stress.

The findings in this study serve practitioners in organizational and leadership development. For one thing, this study contributes to raising awareness about the importance of improving family-related support in the workplace in generating subordinates' positive emotions and relieving their job stress. For another, the findings highlight the necessity of cultivating ethical leadership for leaders.

This study fulfills an identified need to clarify how and when daily family supportive supervisor behaviors influence subordinates' daily job stress. This study moves beyond previous research by adopting the experience sampling method and demonstrating important cross-level effects of ethical leadership on the within-individual relationship between family supportive supervisor behaviors and job stress.

Force output is extremely important for electromagnetic linear machines. The purpose of this study is to explore new permanent magnet (PM) array and winding patterns to increase the magnetic flux density and thus to improve the force output of electromagnetic tubular linear machines.

Based on investigations on various PM patterns, a novel dual Halbach PM array is proposed in this paper to increase the radial component of flux density in three-dimensional machine space, which in turn can increase the force output of tubular linear machine significantly. The force outputs and force ripples for different winding patterns are formulated and analyzed, to select optimized structure parameters.

The proposed dual Halbach array can increase the radial component of flux density and force output of tubular linear machines effectively. It also helps to decrease the axial component of flux density and thus to reduce the deformation and vibration of machines. By using analytical force models, the influence of winding patterns and structure parameters on the machine force output and force ripples can be analyzed. As a result, one set of optimized structure parameters are selected for the design of electromagnetic tubular linear machines.

The proposed dual Halbach array and winding patterns are effective ways to improve the linear machine performance. It can also be implemented into rotary machines. The analyzing and design methods could be extended into the development of other electromagnetic machines.

The purpose of this paper is to propose a multivariate-based method to classify products in replenishment categories based on principal component analysis (PCA) along with two classification algorithms, k-nearest neighbor (KNN) and linear discriminant analysis (LDA).

In the propositions, PCA is applied to data describing products’ features and demand behavior, and a variable importance index (VII) is derived based on PCA parameters. Next, products are allocated to inventory replenishment models applying the KNNs to all original variables; the classification accuracy is then assessed. The variable with the smallest VII is removed and a new classification is carried out; this iterative procedure is performed until a single variable is left. The subset yielding the maximum classification accuracy is recommended for future classification. The aforementioned procedure is repeated replacing the KNN by the LDA.

When applied to real data from a consulting company, the KNN classification technique led to higher performance levels than LDA, yielding 89.4 percent average accuracy and retaining about 80 percent of the original variables. On the other hand, LDA reached 87.1 percent average accuracy and retained 95 percent of the variables. Based on such results, the authors’ findings suggest that 14 out of the 24 variables are crucial in determining an inventory replenishment model for a product in a specific location replacement. Several of the retained variables were typically used in reorder point estimation or associated to market profile in specific locals.

The idea of this paper is to remove irrelevant and noisy market metrics that jeopardize the correct allocation of products to the most appropriate replenishment model.

Due to the merits of direct driven, high thrust density and high efficiency, PM linear synchronous motor (PMLSM) is pretty suitable for the long-stroke ropeless lifter. However, the vibration caused by detent force and difficulty of maintenance become the barriers that restrict its application. The paper aims to discuss these issues.

In order to simplify structure and improve driving performance, a novel PMLSM with segmented armature core and end non-overlapping windings is proposed. The analytical formula of detent force is derived based on energy method and harmonic analysis, which is validated by two-dimensional finite element analysis (FEA). Moreover, with erected parametric FEA calculation, the selection principles of slot-pole number combination and interval distance to this novel structure are obtained. Finally, the heat dissipation ability of conventional PMLSM and novel PMLSM are compared through thermal analysis.

In novel PMLSM, it is found that the (3m+1) and (3m+2) order harmonic components of thrust force are eliminated, which leads to a better driving performance in comparison with the conventional structure. Furthermore, the good heat dissipation ability of novel structure makes it possible for higher thrust density, which is crucial for ropeless lifter.

The novel PMLSM has excellent driving performance, simple structure for maintenance, possibility of modular production and high thrust density. It is a strong candidate for long-stroke ropeless lifter.

The study explores the sustainability of biodegradable materials as an eco-friendly substitute for traditional plastics across diverse applications. These materials decompose harmlessly within a specific timeframe, contributing to a holistic lifecycle. Yet, their widespread adoption depends on convincing consumers, manufacturers and regulators of their effectiveness. An empirical study was undertaken to investigate the determinants impacting the sustainability of biodegradable plastics.

This study employed a quantitative approach, seeking to discern the factors shaping the endurance of these materials in Malaysia. The study encompassed 316 viable responses, with outcomes from the PLS-SEM analysis offering partial support to the research framework.

The study reveals that individual characteristics strongly influence the sustainability of biodegradable plastics and are essential factors in determining behavioural intentions related to sustainability, such as purchasing environmentally friendly packaged food products.

The study provides practical implications for government and corporate sectors to design effective strategies encouraging consumers to choose biodegradable plastics. Regular awareness campaigns should be conducted to increase consumer engagement in environmental concerns and reduce the use of non-eco-friendly packaging in the public sector.

Previous literature has overlooked the sustainability aspects of the biodegradable plastics market, leaving a gap in understanding the influential factors and their sustainability, especially in the Malaysian context. This study aims to fill this gap by exploring the determinants that govern the sustainability of biodegradable plastics.