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Robotic arms’ interactions with the external environment are growing more intricate, demanding higher control precision. This study aims to enhance control precision by establishing a dynamic model through the identification of the dynamic parameters of a self-designed robotic arm.

This study proposes an improved particle swarm optimization (IPSO) method for parameter identification, which comprehensively improves particle initialization diversity, dynamic adjustment of inertia weight, dynamic adjustment of local and global learning factors and global search capabilities. To reduce the number of particles and improve identification accuracy, a step-by-step dynamic parameter identification method was also proposed. Simultaneously, to fully unleash the dynamic characteristics of a robotic arm, and satisfy boundary conditions, a combination of high-order differentiable natural exponential functions and traditional Fourier series is used to develop an excitation trajectory. Finally, an arbitrary verification trajectory was planned using the IPSO to verify the accuracy of the dynamical parameter identification.

Experiments conducted on a self-designed robotic arm validate the proposed parameter identification method. By comparing it with IPSO1, IPSO2, IPSOd and least-square algorithms using the criteria of torque error and root mean square for each joint, the superiority of the IPSO algorithm in parameter identification becomes evident. In this case, the dynamic parameter results of each link are significantly improved.

A new parameter identification model was proposed and validated. Based on the experimental results, the stability of the identification results was improved, providing more accurate parameter identification for further applications.

This study aims to investigate the relationship between risks and the expected return of financial investment because the relationship between them is negative; if the investors agree to the higher level of risk, they have the greater the expected return; therefore, investors always require a degree of proportionality between the risks and returns.

This study applied the standard deviation, variance, coefficient of variation methods and matrix function to measure risks. Besides, the dataset is a return on equity ROE, which is collected in three companies at time series from 2005 to 2020.

When the variance or the standard deviation is higher, the return on the securities is higher, but the securities are a higher risk and vice versa. The results showed risk levels of stocks that are 2.509%, 0.367%, 3.666% and the corresponding return mean of 38.68%, 23.99% and 14.02%.

The results support the portfolio management policy appropriately. This study identifies issues for managers, investors and readers to consider: have a comprehensive solution among microcosmic policies, finance policy, investment policy and other policies to control and balance the relationship between risks and returns; have appropriate policies to regulate funds to stimulate investment in the long term.

This paper aims to investigate the effects of goal orientation on understanding the dynamics of stocks and flows (SF).

The authors use the well-established department store task as the experimental task to evaluate people’s understanding of SF and implement a survey to assess different goal orientation levels. Ordinary least square is used to test the effects of goal orientations on the SF performance.

The findings suggest that learning goal orientation is positively associated with SF performance. However, prove and avoid performance goal orientation are unrelated to SF performance.

The study has important theoretical and practical contributions. From a theoretical perspective, the authors examine the impact of goal orientation in dynamic decision-making to advance the knowledge on the role of goal orientation. Practically, the research demonstrates that learning-goal-oriented people perform better in stock and flow tasks, suggesting that goal orientation is an important trait for recruiting organizational members whose work involves SF decision-making tasks.

Targeting the common functions of the Zhejiang Library website, elderly individuals were invited to complete six experimental tasks on the improved website interfaces, and subjective data (PAD emotion scale and usability evaluation) and objective data (eye movement data) were recorded to verify the effects of graphic layout and navigation position on the information-seeking experience of elderly individuals.

This study analyzes the effect of the graphic layout and navigation position of the Zhejiang Library’s website interface on the emotional state, perceived usability and information-seeking time of elderly individuals, with the aim of providing guidance and suggestions for the elderly-oriented reform of the public library website.

The experimental results show that the graphic layout has a significant effect on the emotional state and perceived usability of elderly individuals, and the navigation position has a significant effect on the information-seeking time; the interaction between graphic layout and navigation position exerts a significant effect on the information-seeking time of elderly individuals. The eye movement data show that elderly individuals have a better information-seeking experience when the top navigation bar and image-text matched arrangement are used for the interface layout.

This study adopts a new approach combining subjective data and eye movement data to evaluate the effect of the public library website’s interface layout on the information-seeking experience for older people. The findings can provide a theoretical basis and methodological support for the elderly-oriented reform of public library websites. They can also provide scientific design suggestions for age-friendly interface layouts of other Internet products and service applications.

The purpose of this paper is to present a Differential Immune Clone Clustering Algorithm (DICCA) to solve image segmentation.

DICCA combines immune clone selection and differential evolution, and two populations are used in the evolutionary process. Clone reproduction and selection, differential mutation, crossover and selection are adopted to evolve two populations, which can increase population diversity and avoid local optimum. After extracting the texture features of an image and encoding them with real numbers, DICCA is used to partition these features, and the final segmentation result is obtained.

This approach is applied to segment all sorts of images into homogeneous regions, including artificial synthetic texture images, natural images and remote sensing images, and the experimental results show the effectiveness of the proposed algorithm.

The method presented in this paper represents a new approach to solving clustering problems. The novel method applies the idea two populations are used in the evolutionary process. The proposed clustering algorithm is shown to be effective in solving image segmentation.

This study explored how organizational leaders at different hierarchical levels may communicatively enhance employees' health and well-being. Drawing on interdisciplinary research, it proposed a model that connects health-oriented leadership communication at supervisory and executive levels with remote workers' self-care and stress levels during the COVID-19 pandemic.

Data collected through a survey of 363 full-time United States (US) employees were analyzed to test the model.

Results showed health-oriented communication at the two leadership levels directly influenced employees' self-care, which in turn reduced their stress levels. Further, executive leaders' health-oriented leadership communication indirectly impacted remote workers' self-care through its positive association with supervisors' health-oriented leadership communication.

This study offers much-needed guidelines for executive leaders, supervisors and communication practitioners seeking to meet employees' growing expectations for a healthy work environment in today's post-pandemic era.

Although the literature has established organizational leadership as a vital determinant for a healthy workforce, few studies have explored leaders' health-specific communication to enhance employee health. This study is the first to conceptualize health-oriented leadership communication at dual hierarchical levels and uncover its influence on employees. The results suggested the importance of health-oriented leadership communication across hierarchical levels in building a healthy workplace.

The purpose of this paper is to examine the evolution of collaboration among researchers in Library Hi Tech based on the co-authorship network analysis.

The Library Hi Tech publications were retrieved from Web of Science database between 2006 and 2017. Social network analysis based on co-authorship was analyzed by using BibExcel software and a visual knowledge map was generated by Pajek. Three important social capital indicators: degree centrality, closeness centrality and betweenness centrality were calculated to indicate the co-authorship. Cohesive subgroup analysis which includes components and k-core was then applied to show the connectivity of co-authorship network of Library Hi Tech.

The results indicated that around 42 percent of the articles were written by single author, while an increasing trend of multi-authored articles suggesting the collaboration among researchers in librarian research field becomes popular. Furthermore, the social network analysis identified authorship network with three core authors – Markey, K., Fourie, I. and Li, X. Finally, six core subgroups each included six or seven tightly connected researchers were also identified.

This study contributed to the existing literature by revealing the co-authorship network in librarian research field. Key researchers in the major subgroup were identified. This is one of the limited studies that describe the collaboration network among authors from different perspectives showing a more comprehensive co-authorship network.

This paper aims to study the impact of manufacturer’s upgrading strategy of durable products on the retailer’s decision on trade-in program and her decision on the secondary market.

This paper develops a channel that consists of a manufacturer and a retailer, where the manufacturer releases an upgraded product, and the retailer introduces a trade-in program for consumers, simultaneously, decides whether to enter the secondary market. These approaches are modeled through Stackelberg game.

This paper reveals that the optimal conditions for manufacturer to release upgraded products and retailer to resell used products in the secondary market, and it reveals that under what conditions it is profitable for retailer to enter the secondary market under product upgrade levels.

If the manufacturer’s upgrade level is low, it is profitable for the retailer to enter the secondary market. However, if the manufacturer’s upgrade level is high, it is unprofitable for the retailer to enter the secondary market.

In this paper, the active secondary market, upgrading of new products, consumer market segmentation and especially, the upgrade degree of new products as a function of consumer demand are considered simultaneously.

The purpose of the investigation was to research the best process of electroless nickel (EN) plating on AZ91D magnesium alloy and the performance of EN plating coating.

Through single factor test and orthogonal test, EN plating on AZ91D magnesium alloy was researched. The plating rate and porosity were analyzed. The coating appearance of EN plating coating and magnesium alloy substrate was evaluated. The electrochemical properties of EN plating coating and substrate were researched using electrochemical workstation, and their compositions and structure were examined using X-ray diffraction and scanning electron microscopy.

The results made by combination of experimental and orthogonal test showed that the best formula of EN plating was 8.8 g·L⁻¹ nickel ion, 25 g·L⁻¹ lactic acid, 28 g·L⁻¹ reducing agent, 1.8 ml·L⁻¹ corrosion inhibitor, 1 mg·L⁻¹ stabilizer, temperature at 85°C and pH value at 5.5. The plating was uniform, dense and with no cracks. The electrochemical tests showed that the corrosion resistance of EN plating was better than that of magnesium alloy substrate.

The results indicated that the corrosion resistance of magnesium alloy improved markedly after EN plating at the best formula and the plating covered magnesium alloy completely.

Opaque selling has become popular among service providers in recent years. Although many researchers have investigated the optimality of opaque selling for service providers focusing on heterogeneous consumers, one question remaining unexplored is how the service providers’ optimal decisions are impacted by competitive intensity in a heterogeneous market. This paper aims to determine the conditions under which opaque selling is optimal for competing service providers.

The paper takes a Hotelling model to characterize the competition between two service providers. The authors also consider the interaction between the service providers and intermediary. Service providers act as game leaders and determine whether they should cooperate with the intermediary to introduce the opaque service.

The authors find that two competing service providers do not always benefit from opaque selling in a heterogeneous market consisting of leisure and business consumers, and the competitive intensity plays a significant role in the service providers’ decision optimization. Opaque selling allows service providers to acquire more profit in a highly competitive market or when the market contains a large proportion of leisure consumers. Otherwise, it is optimal for service providers without introducing the opaque selling.

The paper examines the optimality of opaque selling for competing service providers, and provides the suggestions to optimize the service providers’ decisions.

The paper investigates how the service providers’ optimal decisions are impacted by competitive intensity, considering the interaction between the service providers and intermediary.