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This paper aims to investigate the effect of coating microstructure, mechanical and oxidation property on the tribological behaviour of low-pressure plasma spraying (LPPS) tungsten carbide/cobalt (WC-Co) coatings.

WC-12Co and WC-17Co coatings were deposited via the LPPS spraying method. Tribological tests on the coatings were performed using a high-temperature ball-on-disc tribometer at temperatures from room temperature (RT, approximately 25 °C) up to 800 °C in ambient air.

WC-12Co coating contained brittle phases, pores and microcracks, which led to the low hardness, and finally promoted the splat delamination and the carbide debonding during wear. WC-17Co coating had higher cobalt content which benefited the coating to contain more WC particles, less brittle phases, pores and nearly no microcracks, and resulted in the high hardness and better wear resistance. Higher cobalt content also decelerated the oxidation rate of the coating and promoted the formation of cobalt oxides and CoWO4, which were able to maintain the load-bearing capacity and improve the tribological behaviour of the coating below 650°C. Above 650°C, the increase of oxidation degree and the decrease of mechanical property deteriorated the wear resistance of coatings.

The LPPS WC-Co coating with higher cobalt content had better tribological properties at different temperatures. The LPPS WC-Co coatings should not be used as wear-resistant coatings above 650 °C.

The disjunctive graph is a network representation of the job‐shop scheduling problem, while the longest path problem (LPP) is one of the most important subjects in this research field. This paper aims to study the special topological structure of the disjunctive graph, and proposes a suite of quick value‐setting algorithms for solving the LPPs commonly encountered in job‐shop scheduling.

The topological structure of the disjunctive graph is analyzed, and some properties and propositions regarding LPPs are presented. Subsequently, algorithms are proposed for solving LPPs encountered in job‐shop scheduling.

The proposed algorithms significantly improve the efficiency of the shifting‐bottleneck procedure, making it practicable to realise real‐time scheduling and hence effective operations of modern manufacturing systems.

The paper demonstrates that it is possible to develop very efficient algorithms by imposing a special topological structure on the network.

Informed by learning transfer theory, the purpose of this paper is to validate the instrument measuring educational leadership preparation program (LPP) quality attributes and graduates’ leadership learning and to assess the direct and indirect relationships among them, as reported by program graduates.

This study uses data collected from the 2016 INSPIRE-G Survey, which gathers information from LPP graduates in the USA on their perceptions of program quality and leadership learning. Structural equation modeling was used to determine which program quality factors directly and indirectly influence graduate leadership learning.

The results suggest significant relationships between the assessed LPP attributes and leadership learning. Faculty quality and program rigor and relevance (PRR) had the strongest association with leadership learning, although the relationship between faculty quality and learning was fully mediated by PRR. Internship experiences and peer relationships were also important predictors of leadership learning. Studying with a cohort had a small but positive relationship with graduates’ leadership learning, although the relationship was fully mediated by perceived peer relationships.

This study further validates the INSPIRE-G Survey and affirms the imperative role of leadership preparation as a predictor to graduate reported learning outcomes and learning transfer. Moreover, this study illustrates the importance of leadership preparation by demonstrating positive relationships between program quality features and reported leadership learning outcomes. Finally, the INSPIRE-G instrument demonstrates its utility as a reliable measure of program quality, which opens the door to large-scale and longitudinal studies of the transfer of learning from leader preparation to practice.

This study aims to analyze the experiences of a closed cohort of aspiring leaders and connects the university and school district partnership relationship to building the leadership capacity of the cohort. This study builds on previous literature in district-university partnerships and leadership preparation. Powerful learning experiences (PLEs) and interpersonal-intrapersonal leadership development models serve as frames to examine how aspects of successful leadership preparation programs were present.

This qualitative study was conducted with a team of researchers from the university and school district and relies on data from semi-structured interviews with students from the closed cohort.

Researchers identified three major themes of aspiring leaders' preparation experience: confidence building, reflection and mindset change.

This study contributes to the emerging literature on PLEs by illustrating how this type of partnership creates opportunities for powerful learning experiences for aspiring school leaders.

Sifco Ireland is investing over £1.6 million in new plant to protect components from the very high temperatures experienced in the new generation of aero engines developed by Rolls‐Royce, Pratt & Whitney, CFMI and GE. An order has been placed with Sulzer Metco of Newport Gwent for its low pressure plasma spraying system (LPPS).

The purpose of this paper is to consider extension of the Kőnig‐Egerváry theorem to apply to matrices of dimensionality greater the two. It is shown that the theorem holds for matrices of any dimensionality, in the standard case where “cover” of selected elements is by lines, and the criterion for independence is also with reference to lines. Attention is also given to the case where cover and (hyper‐independence) are with reference to planes, or submatrices of higher dimensionality, rather than lines, and counter‐examples are given that show the theorem does not then hold universally. A preliminary survey is made of the diverse proofs that have been devised for the basic theorem, and in an Appendix an approach to the multidimensional Transportation Problem is reviewed.

Interest in generalisation of the theorem arose from the attempt to extend the Hungarian Method for the Assignment Problem to higher dimensionality. The results are also interesting as purely mathematical theory.

The theorem has been shown to extend to the multidimensional case when cover and independence are defined with reference to lines, but not universally otherwise.

Extension of the theorem to higher dimensionality has not produced a rigorous corresponding extension of the Hungarian Method, but may stimulate further studies. An approximate extension of the method (approximate insofar as it gives no guarantee of convergence on an optimum) will be described in a later publication. The study of the multidimensional Transportation Problem, reviewed in the Appendix, confirms the general difficulty of extending a class of methods from elegant solutions in the two‐dimensional case to versions for higher dimensionality.

The paper's results are believed to be original. Their main value is likely to be in stimulating interest that may lead to further developments as suggested.

The purpose of this paper is to provide an economic assessment of the productivity growth and technical efficiency of US Class I railroads for the period of 2002‐2007.

The US railroad industry has become increasingly concentrated with seven Class I railroads accounting for over 90 percent of the industry's revenue. Because the small sample size creates a dimensionality problem for data envelopment analysis (DEA) with contemporaneous frontiers, the authors use sequential DEA and calculate the Malmquist productivity indexes using sequential frontiers. Through a decomposition process, changes in productivity are attributed to technical efficiency change, technical change, and scale efficiency change.

Burlington Northern Santa Fe (BNSF) led the industry in terms of productivity growth (4.6 percent) and consistently stayed on the production frontier in every period studied; both BNSF and Union Pacific (UP) are top innovators in the industry, but UP trailed BNSF in both productivity growth and technological innovations by wide margins; and Grand Trunk Corporation was very good at “catching up” or leading its peers in efficiency improvements.

Railroads have invested heavily in technology over the years to enhance efficiency and productivity. However, two recent economic studies find that railroad productivity has slowed in recent years. The authors' benchmarking analysis sheds light on how individual railroads performed relative to their peers, and what they could learn from industry best practice.

The benchmarking study enables the authors to report each railroad's performance instead of reporting industry‐wide aggregate indexes or industry averages which tend to mask performance variations. The paper also examines the causal factors of recent productivity growth and provides useful information for the industry and its regulators.

The kitting feeding policy creates kits with the parts of each product to assemble. Each kit contains elements with heterogeneous physical properties imposing heterogeneous logistic facilities and management solutions for storage and handling. The purpose of this paper is to present and apply a two-step procedure to design the part warehouse layout and to assign locations in case of kitting with high-variety part attributes. The proposed procedure aims at reducing the kitting travelled distance, shortening the picker paths, best positioning the components in the warehouse to enhance the possibility of creating kits through a single corridor access. The saturation of the warehouse and the minimization of the required storage space are also considered.

Starting from part categorization, the proposed two-step procedure, of general applicability, designs the component warehouse, sizing the corridors (Step 1) before clustering the kits in terms of part commonality and best-assigning clusters to corridors (Step 2) with the goal of reducing the travelled distance and saturating the available storage space.

A comparison model considers the traditional versus the proposed warehouse layout highlighting the potential saving in the picker travelled distance. A case study taken from the harvesting machine agricultural sector exemplifies the applicability and the practical implications of this research.

Elements of originality are the warehouse design strategy and the assignment model for parts based on their physical attributes and their occurrence in the assembly kits. Finally, the case study taken from industry, with a high number of components and part categories, adds value to the research making the proposed procedure able to address large-scale industrial problems.

In periods of economic distress, expectations for businesses change and there is a heightened need for reporting quality. This study investigates the impact of crises on earnings management in the real estate sector.

The data consisted of financial statements from 2005 to 2021 from real estate firms listed on 10 European stock exchanges. Estimated discretionary accruals from four standard accruals models were used as a proxy for earnings management, using cross-sectional industry and firm fixed effects models. The authors examined earnings management during three crises: the financial crisis (2008–2009), the debt crisis (2011–2012) and the COVID-19 pandemic (2020–2021).

The results showed less earnings management during the COVID-19 crisis and more earnings management during the financial crisis, though with slightly weaker evidence. The authors did not find significant evidence of earnings management related to the debt crisis. These results suggest that stakeholders in the real estate sector should be extra vigilant in crisis periods.

This study is the first to investigate earnings management in European real estate firms, focusing on the impact of crises.