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Online grocery stores are facing challenges. The intense competition in the online grocery market has driven companies to seek technological innovation. Moreover, the operations of online grocery stores on both the supply and demand sides are not sufficiently meeting the requirements of consumers and managers. The powerful capabilities of the Generative Pre-Trained Transformer (GPT) technology align with the needs of online grocery stores for innovation and upgrading. This study uniquely leverages GPT’s advanced natural language processing, adaptive learning and generative capabilities to analyze and optimize the online grocery supply chain competition in ways not possible with traditional analytical tools.

This paper constructs a Stackelberg game model, comprising a secondary supply chain consisting of a supplier who provides products and a retailer who sells them. This study explores the impact of GPT technology on online grocery store operations from the demand side and supply side, specifically including the value of service information, demand information and information-sharing behavior.

The findings reveal several vital conclusions: (1) On the demand side, the service information plays a crucial role in enhancing service levels and increasing consumer demand; (2) On the supply side, demand information provides positive incentives for retailers and suppliers and (3) Information-sharing behaviors can lead to cooperative relationships between upstream and downstream supply chain members, significantly increasing their respective service levels. This study not only explores the impact of GPT on the online grocery supply chain but also presents a rigorous framework for validating GPT-generated insights, ensuring the reliability of our findings.

This study provides valuable insights into a promising field. It employs game theory to analyze the impact of GPT technology on the overall operation of the online grocery supply chain and the market strategy of online grocery stores.

This study aims to investigate the synergistic friction reduction and antiwear effects of lyophilized graphene loading nano-copper (RGO/Cu) as lubricating oil additives, compared with graphene.

The friction performance of freeze-drying graphene (RGO) and RGO/Cu particles was investigated at different addition concentrations and under different conditions.

Graphene plays a synergistic friction reduction and antiwear effect because of its large specific surface area, surface folds and loading capacity on the nanoparticles. The results showed that the average friction coefficients of RGO and RGO/Cu particles were 22.9% and 6.1% lower than that of base oil and RGO oil, respectively. In addition, the widths of wear scars were 62.3% and 55.3% lower than those of RGO/Cu particles, respectively.

The RGO single agent is suitable for medium-load and high-speed conditions, while the RGO/Cu particles can perform better in the conditions of heavy load and high speed.

The incorporation of phosphide additives is regarded as a highly effective strategy for enhancing the lubricative qualities of base oils. This study aims to assess the lubrication behavior and efficacy of various phosphide additives in polyethylsiloxane (PES) through the employment of the Schwingum Reibung Verschleiss test methodology, across a temperature range from ambient to 300°C.

PES demonstrated commendable lubrication capabilities within the Si3N4/M50 system, primarily attributable to the Si-O frictional reaction film at the interface. This film undergoes disintegration as the temperature escalates, leading to heightened wear. Moreover, the phosphide additives were found to ameliorate the issues encountered by PES in the Si3N4/M50 system, characterized by numerous boundary lubrication failure instances. A chemical film comprising P-Fe-O was observed to form at the interface; however, at elevated temperatures, disintegration of some phosphide films precipitated lubrication failures, as evidenced by a precipitous rise in the coefficient of friction.

The results show that a phosphide reactive film can be formed and a reduction in wear rate is achieved, which is reduced by 64.7% from 2.98 (for pure PES at 300°C) to 1.05 × 10^–9 μm³/N m (for triphenyl phosphite at 300°C).

The data derived from this investigation offer critical insights for the selection and deployment of phosphide additives within high-temperature lubrication environments pertinent to PES.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0139/

The purpose of this paper is to check and fill the gap between the existing fire safety regulations for newly built tall buildings in Bulgaria and those in areas with rapid economic growth in the Asia-Oceania regions like the Hong Kong Special Administrative Region and Mainland China, by making comparative analysis and identifying good practices. The main focus is on the development of fire safety designs, facilities and management, which shall be recognized as essential parts of facility management in tall buildings.

Bulgarian regulations are analyzed and then compared with those in the Hong Kong Special Administrative Region and Mainland China. In addition, the scientific aspect of fire load density in the fire codes is discussed. The possibility of implementing a fire engineering approach to supplement prescriptive codes is outlined. The essential roles of fire safety management and fire safety culture are presented.

Key points and recommendations that are worthy for discussion about incorporation in the Bulgarian tall buildings fire safety requirements are upgraded requirements for fire load density, detection and sprinkler systems in tall residential buildings, refuge floors, ventilation/air conditioning control systems, full-scale burning tests and fire engineering approach. The importance of fire safety management is emphasized as a main, key component in facility management.

The research is the first study focusing on implementation of additional and specific fire safety regulations for tall buildings in Bulgaria.

The purpose of this paper is to explore the possibility of combining additive manufacturing (AM) with topology optimization to generate support structures for addressing the challenging overhang problem. The overhang problem is considered as a constraint, and a novel algorithm based on continuum topology optimization is proposed.

A mathematical model is formulated, and the overhang constraint is embedded implicitly through a Heaviside function projection. The algorithm is based on the Solid Isotropic Material Penalization (SIMP) method, and the optimization problem is solved through sensitivity analysis.

The overhang problem of the support structures is fixed. The optimal topology of the support structures is developed from a mechanical perspective and remains stable as the material volume of support structures changes, which allows engineers to adjust the material volume to save cost and printing time and meanwhile ensure sufficient stiffness of the support structures. Three types of load conditions for practical application are considered. By discussing the uniform distributive load condition, a compromise result is achieved. By discussing the point load condition, the removal work of support structures after printing is alleviated. By discussing the most unfavorable load condition, the worst collapse situation of the printing model during printing process is sufficiently considered. Numerical examples show feasibility and effectiveness of the algorithm.

The proposed algorithm involves time-consuming finite element analysis and iterative solution, which increase the computation burden. Only the overhang constraint and the minimum compliance problem are discussed, while other constraints and objective functions may be of interest.

Compared with most of the existing heuristic or geometry-based support-generating algorithms, the proposed algorithm develops support structures for AM from a mechanical perspective, which is necessary for support structures particularly used in AM for mega-scale construction such as architectures and sculptures to ensure printing success and accuracy of the printed model.

With the rapid development of AM, complicated structures result from topology optimization are available for fabrication. The present paper demonstrates a combination of AM and topology optimization, which is the trend of fabricating manner in the future.

This paper remarks the first of attempts to use continuum topology optimization method to generate support structures for AM. The methodology used in this work is theoretically meaningful and conclusions drawn in this paper can be of important instruction value and practical significance.

The purpose of this paper is to analyze the micro-motion of the cylinder block.

Based on the elasto-hydrodynamic lubrication, a numerical model for the cylinder block/valve plate interface is proposed, with consideration of the elastic deformations, the pressure-viscosity effect and asperity contacts. The influence-function method is applied to calculating the actual deformations of the cylinder block and the valve plate. The asperity contact model simplified from Greenwood assumption is introduced into the numerical model. Furthermore, the relationship between the micro-motion and the operating condition, the sealing belt width is discussed, respectively.

The results show an increase in the discharge pressure causes the tilt state and the vibrating motion getting worse, which can be eased by improving the rotational speed, the sealing belt width and the ratio of external and internal sealing belt width.

The proposed research can provide a theoretical reference for the optimizing design of cylinder block/valve plate pair.

The purpose of this paper is to investigate the effects of chief executive officer (CEO) international work experience, functional background and career concerns on managerially-distorted investment decisions.

This paper focuses on S&P 500 publicly held US manufacturing companies during the period from 2009 to 2012. The data related to the CEOs’ international experience and their functional background experience are manually collected from Business Week’s Corporate Elite. Financial data is retrieved from COMPUSTAT database. The data for CEO tenure and age are retrieved from the ExecuComp database. Besides ordinary least squares regression, this paper conducts two-stage least squares regression analysis. Endogeneity and additional tests are also considered in this paper.

The findings show that CEO international work experience may not reduce under-investment, but it may exacerbate over-investment. CEO throughput functional background may exacerbate under-investment, but it may not reduce over-investment. Furthermore, CEO career concerns are useful in reducing the inefficient investments caused by international work experience and throughput functional background. These results remain similar when potential self-selection bias, as well as alternative measures of career concerns and investment efficiency, are considered.

This paper contributes to the existing literature in the following ways: first, while a significant amount of attention has been paid to how investment decisions are affected by financial reporting quality and material internal control weaknesses, there has been little evidence accumulated related to how managers’ international experience, professional background and career concerns affect investment inefficiency. The authors attempt to fill this gap. Second, the authors manually collect the international experience and functional backgrounds of CEOs working for S&P 500 US manufacturing companies. This unique data set makes it possible to complement previous studies by investigating the effects of managerial international experience and functional background on investment behavior. Finally, previous theoretical studies have long recognized that managers’ career concerns affect their corporate investment decisions. These studies suggest that young CEOs have a greater incentive to signal their abilities by adopting more active and possibly riskier investment strategies, thus raising the moral hazard problem with regard to firm investments. The authors enrich these studies by showing that work experience alleviates the moral hazard problem with respect to young CEOs’ investment decisions.

Persistent change has placed considerable pressure on organizations to keep up or fade into obscurity. Firms that remain viable, or even thrive, are staffed with decision-makers who capably steer organizations toward opportunities and away from threats. Accordingly, leadership development has never been more critical. In this chapter, the authors propose that leader development is an inherently dyadic process initiated to communicate formal and informal expectations. The authors focus on the informal component, in the form of organizational politics, as an element of leadership that is critical to employee and company success. The authors advocate that superiors represent the most salient information source for leader development, especially as it relates to political dynamics embedded in work systems. The authors discuss research associated with our conceptualization of dyadic political leader development (DPLD). Specifically, the authors develop DPLD by exploring its conceptual underpinnings as they relate to sensemaking, identity, and social learning theories. Once established, the authors provide a refined discussion of the construct, illustrating its scholarly mechanisms that better explain leader development processes and outcomes. The authors then expand research in the areas of political skill, political will, political knowledge, and political phronesis by embedding our conceptualization of DPLD into a political leadership model. The authors conclude by discussing methodological issues and avenues of future research stemming from the development of DPLD.

We examine changes in controlling shareholder holdings, looking for evidence of financial tunneling (unfair wealth transfers from public investors to controlling shareholders). Our sample comprises yearly data during 2000–2011 on 75 large Israeli companies. We find that controlling shareholders are successful in timing the stock market – there exists a significant negative correlation between changes in the mean controlling shareholders’ equity holdings and market return. There is also some evidence that controlling shareholders increase (decrease) their holdings before years of positive (negative) excess returns in their shares. However, statistically significant mean excess returns are documented only after decreases in controlling shareholders’ holdings. Thus, we offer only limited support for the financial tunneling hypothesis.

Stewardship theory is an emergent approach for explaining leadership behavior, challenging the assumptions of agency theory and its dominance in corporate governance literature. This study revisits the agency and stewardship theories by seeking to answer whether chief executive officers (CEOs) in China are committed stewards or opportunistic agents.

Based on 5,165 observations of 1,036 listed companies in China over the period 2005–2010, the results suggest that the corporate governance mechanisms developed from the agency theory in the West are not necessarily applicable in the Chinese context.

This study supports the stewardship theory in its findings that empowering CEOs through the practice of CEO duality and longer CEO tenure have a positive effect on firm value in China. Additionally, the positive relationships between CEO duality, CEO tenure and firm value are strengthened by the number of executive directors on the board, and weakened by the number of independent directors on the board.

One size does not fit all. Leadership behaviors in China do not follow the agency assumptions inherent in Western practices, rather they favor the conditions of positive leadership expressed by the stewardship theory. Assuming that the motivations of managers in emerging markets such as China are similar to those in the West may lead to a poor fit between governance policies and the institutional context.

As one of the few studies to connect the theoretical debate between the agency and stewardship theories, this study presents new evidence to support the stewardship theory, thereby strengthening its theoretical importance and relevance in corporate governance literature.