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Airports are limited in terms of capacity. Particularly, runways can only accommodate a certain number of movements (arrivals and departures) while ensuring safety and determined operational requirements. In such a constrained operating environment, any reduction in system capacity results in major delays with significant costs for airlines and passengers. Therefore, the efficient operation of airports is a critical cornerstone for demand and delay management of the whole air transportation system. Runway scheduling deals with the sequencing of arriving and departing aircraft at airports such that a predefined objective is optimized subject to several operational constraints, like the dependency of separation on the leading and trailing aircraft type or the runway occupancy time. This study aims to develop a model that acts as a tactical runway scheduling methodology for reducing delays while managing runway usage.

By considering real airport performance data with scheduled and actual movements, as well as arrival/departure delays, this study presents a robust model together with an optimization algorithm, which incorporates the knowledge of uncertainty into the tactical operational step. The approach transforms the planning problem into an assignment problem with side constraints. The coupled landing/take-off problem is solved to optimality by exploiting a time-indexed (0, 1) formulation for the problem. The Binary Integer Linear Programming approach allows to include multi-criteria and multi-constraints levels and, even with some major simplifications, provides fewer sequence changes and target time updates, when compared to the usual approach in which the plan is simply updated in case of infeasibility. Thus, the use of robust optimization leads to a protection against tactical uncertainties, reduces delays and achieves more stable operations.

This model has been validated with real data from a large international European airport in different traffic scenarios. Results are compared to the actual sequencing of flights and show that the algorithm can significantly contribute to the reduction of delay, while adhering as much as possible to the operative procedures and constraints, and to the objectives of the airport stakeholders. Computational experiments performed on the case study illustrate the benefits of this arrival/departure integrated approach: the proposed algorithm significantly reduces weighted aircraft delay and computes efficient runway schedule solutions within a few seconds and with little computational effort. It can be adopted as a decision-making tool in the tactical stage. Furthermore, this study presents operational insights regarding demand and delay management based on the results of this work.

Scheduling arrivals and departures at runways is a complex problem that needs to address diverse and often competing considerations among involved flights. In the context of the Airport Collaborative Decision Making programme, airport operators and air navigation service providers require arrival and departure management tools that improve aircraft flows at airports. Airport runway optimization, as the main element that combines airside and groundside operations, is an ongoing challenge for air traffic management.

This paper reviews literature on interim leadership and management through the lens of effective interim performance. The purpose of this review is to advance understanding of interim assignment performance and the antecedent individual psychological characteristics of effective interim leaders and managers, to improve the practice of managing interim leaders from a human resources (HR) perspective.

The paper reports a targeted review of the literature on interim leadership and management.

The main proposition from this review is that the influence of individual factors on interim performance operates within the stages and contexts of assignments. Accordingly, the authors propose a framework of the demands on interim assignments (the interim assignment cycle), comprising stages of preparation, entry, delivery and exit. The paper subsequently reviews evidence of the potential individual characteristics (focussing on individual differences in personality, leadership approach, motivation and competencies) of effective preparation and entry to an assignment, actions and performance during an assignment and exit/disengagement.

The findings of the review have implications for the selection and placement of interims into organizations and their management once appointed.

The main original contribution of the paper is to provide a framework around which interim assignments can be modelled and better understood. The paper discusses implications for future research, theory and human resource management practice and calls for a renewed research effort in this critical area of management and leadership.

Under club president Florentino Pérez, Real Madrid Football Club appeared to utilise the proto-image of the firm (PIF) management approach. Such a strategy embraces the use of branding, values and mid- to long-term planning to generate income. In the case of Real Madrid, the strategy comprised the recruitment of 'Galácticos', which helped it to become the world's number one club in terms of both turnover and profile. Although the strategy delivered success economically, questions remain regarding its sustainability for a sporting organisation.

Participation, teamwork, innovation, risk‐taking and empowerment. We all know the buzz words. But how do we bring the concepts successfully to fruition? Provides some important clues.

The article investigates the patterns of asset impairment recognition in search of signs of “big bath” earnings management practices across an internationally diversified sample of public companies. It also elucidates the incentives that may underlie such practices and explores possible safeguards embedded in the existing corporate governance mechanisms.

The article applied static panel and binary logit models to an international firm-level panel dataset of 1045 public companies observed between 2003 and 2018.

Our empirical results suggest that recognition of asset impairment has no determinate impact on earnings volatility. Investigating the possibility of “big bath” earnings management practices, the authors found no impact of asset impairment recognition on total senior executive compensation in firms, which pay performance-based remuneration. The quality of corporate governance has appeared to impact the firms’ intertemporal proclivity to recognize asset impairment with those having the more entrenched and management-controlled boards being more likely to time impairment recognition by delaying it during exceptionally good and exceptionally bad years. While generally unlikely, recognition of asset impairment in a period with a recorded negative operating performance is found to be closely associated with key executive departures.

The article corroborates the salient role of corporate governance mechanisms in shaping the intertemporal patterns of asset impairment recognition. The possible remedies to the phenomenon should be derived therefrom.

Traditional expatriate predeparture training has been general in nature, neglecting the input of the respective host country workforce (HCW) in identifying specific work interaction demands for optimizing expatriate management performance. This study found that workforces from Mexico, Indonesia and the USA differed significantly in their perceptions of both positive and negative behaviors affecting their work performance. Accordingly, the paper calls for a significant change in research and practice to incorporate the voice of the HCW to develop more valid and effective predeparture training for expatriate managers to enhance their performance in the host country to which they are assigned.

The literature on supply chain risk management (SCRM) has investigated a multitude of supply chain risks. This paper aims to make a case for the importance of managing the risk of knowledge loss in the supply chain management (SCM) function and incorporating knowledge loss as a critical risk within the SCRM process.

This paper adopts a knowledge-based view of the SCRM process and attempts to bring to light insights based on a synthesis of the relevant literature. The authors conducted a systematic literature review of peer-reviewed articles published between 1998 and 2019. Further, a case study was conducted to illustrate the significance of the risk of knowledge loss in the SCM function in terms of how it operates and why it has such a significant impact on performance.

Knowledge loss is a relatively neglected type of supply chain risk that can be added to the existing typologies. This paper argues that knowledge loss in the SCM function has the propensity to significantly impact the performance of the focal firm, exacerbate other types of supply chain risk and impede risk mitigation efforts. We put forth several strategies that supply chain managers can adopt to mitigate the risk of knowledge loss in their function.

This paper generates an exploratory opening that could pave the way for a systematic theory of knowledge loss as a supply chain risk and future empirical research. The study culminates in a number of important insights and initiatives for supply chain managers to recognize and manage the risk of knowledge loss.

This paper argues for the importance of incorporating the risk of knowledge loss in SCRM research and practice. It also provides an examination of some promising angles for future research in SCRM from a knowledge-based perspective.

An important and challenging question for air transportation regulators and airport operators is the definition and specification of airport capacity. Annual capacity is used for long-term planning purposes as a degree of available service volume, but it poses several inefficiencies when measuring the true throughput of the system because of seasonal and daily variations of traffic. Instead, airport throughput is calculated or estimated for a short period of time, usually one hour. This brings about a mismatch: air traffic forecasts typically yield annual volumes, whereas capacity is measured on hourly figures. To manage the right balance between airport capacity and demand, annual traffic volumes must be converted into design hour volumes, so that they can be compared with the true throughput of the system. This comparison is a cornerstone in planning new airport infrastructures, as design-period parameters are important for airport planners in anticipating where and when congestion occurs. Although the design hour for airport traffic has historically had a number of definitions, it is necessary to improve the way air traffic design hours are selected. This study aims to provide an empirical analysis of airport capacity and demand, specifically focusing on insights related to air traffic design hours and the relationship between capacity and delay.

By reviewing the empirical relationships between hourly and annual air traffic volumes and between practical capacity and delay at 50 European airports during the period 2004–2021, this paper discusses the problem of defining a suitable peak hour for capacity evaluation purposes. The authors use information from several data sources, including EUROCONTROL, ACI and OAG. This study provides functional links between design hours and annual volumes for different airport clusters. Additionally, the authors appraise different daily traffic distribution patterns and their variation by hour of the day.

The clustering of airports with respect to their capacity, operational and traffic characteristics allows us to discover functional relationships between annual traffic and the percentage of traffic in the design hour. These relationships help the authors to propose empirical methods to derive expected traffic in design hours from annual volumes. The main conclusion is that the percentage of total annual traffic that is concentrated at the design hour maintains a predictable behavior through a “potential” adjustment with respect to the volume of annual traffic. Moreover, the authors provide an experimental link between capacity and delay so that peak hour figures can be related to factors that describe the quality of traffic operations.

The functional relationships between hourly and annual air traffic volumes and between capacity and delay, can be used to properly assess airport expansion projects or to optimize resource allocation tasks. This study offers new evidence on the nature of airport capacity and the dynamics of air traffic design hours and delay.

The purpose of this paper is to assess the immediate and lagged effects of founder's turnover on firm performance, and test the moderating effects of enterprise scale and founders' tenure on enterprise performance.

The paper selects 307 listed companies founded by founder from the Listed Company's Financial Database provided by the China Center for Economic Research. Based on 1,535 observations, this paper tests the relationship between founder turnover and performance by using the random effect model and the fixed effect model.

It is found that founders' turnover will have a significant immediate and negative effect on firm performance. There exists a lagged effect of founders' turnover, but this lagged effect is not as strong as immediate effect. It is also found that the effect of founders' turnover has been moderated by firm size and founders' characteristics.

Founders should choose an appropriate time of leaving when the firm's performance has reached a level high enough for the successor to have a better chance of improving its future operations.

Although some scholars have recognized the special role of founders and that enterprises' performances are mainly determined by the founders, few have studied founders' turnover on firm performance directly and empirically. This paper expands understanding of the founders' departure behavior on firm performance.

This study aims to examine whether managers use discretion in determining transitional goodwill impairment loss (initial impairment loss or IIL) upon the adoption of SFAS no. 142, Goodwill and Other Intangible Assets, and whether and how the market reacts to the impairment loss and to the absence of goodwill amortization.

Various empirical models are applied to a sample of 870 firms that completed the IIL test.

It is found that more highly leveraged firms (firms that have undergone a recent management change) report lower (greater) goodwill impairment. Stock return is not associated with a boost in earnings caused by elimination of goodwill amortization, but it is negatively associated with an unexpected IIL, with the association being stronger for highly leveraged firms. Subsequently, analysts revise earnings forecasts for upcoming quarters downward in response to the unexpected IIL.

Possibility of measurement errors in proxies is a caveat.

The findings are consistent with the strategic reduction of the goodwill impairment by management to avoid the violation of debt covenants and with the notion that new managers take a big bath so they can report higher earnings in the future. The market tests imply that unexpected IIL provides value‐relevant information about a negative view of the future profit‐making potential of the firm or an adverse impact on its debt contracts. No association with elimination of goodwill amortization can be interpreted as the market's anticipation or the lack of information content in goodwill amortization.

This research helps better understand the importance of managers' incentives in determining IIL as well as the stock market effect of the announcement of the IIL and the exclusion of goodwill amortization.