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The purpose of this paper is to build on the research-supported view that interactions between top and middle management enhances effective implementation of organizational strategies by exploring the role of internal actors in driving organizational strategy at the intersection between strategy formulation and strategy implementation.

Adopting a social practice perspective, we undertook semi-structured interviews of 27 top and middle level managers drawn from a single case organization. Data collected were analysed using thematic analysis.

Differences in managerial perception of strategy has significant impact on implementation of strategic decisions as well as creating tensions in recursive communication practices between internal social actors. Furthermore, individual perceptions cannot only limit the extent of strategy awareness amongst key actors, the manifestations through social interaction between top and middle managers is a critical determinant of effective communication and realization of organizational strategy.

The research contributes to the strategy process and practice literature by exploring the dynamic interactions taking place at the intersections of strategy formulation-implementation phases of organizational strategy. It particularly highlights practical issues in top and middle manager interactions and implications for successful strategy implementation.

The purpose of this paper is to investigate consensus formation among the top and middle managers during the strategy process. Specifically, the paper seeks to gain insight into the role of strategic consensus during the transition between strategy formulation and implementation.

Adopting a social practice perspective and a single case study approach, we undertook semi-structured interviews of twenty-seven managers working in a Kuwaiti Ministry. Data collected were analyzed using thematic analysis.

We found that social interaction among individuals with similar characteristics and shared understanding fosters consensus. Factors such as alignment of strategic priorities, managerial flux and centralized control contribute to the extent to which strategic consensus is achievable. Additionally, managerial turnover and lack of empowerment hamper the development of shared understanding. Finally, that consensus on strategy content is insufficient for effective intergroup communications.

The research contributes to the strategic consensus literature from a social practice perspective as it provides new insights into the dynamics between top managers and middle managers. Significantly, it highlights the importance and need for common understanding, as well as communications prioritization among managers for consensus development and successful implementation of organization strategy.

This study comprehensively aims to review the key influential and intellectual aspects of spillovers between Islamic and conventional financial markets.

The study uses the bibliometric and content analysis methods using the VOSviewer software to analyse 52 academic documents derived from the Web of Sciences (WoS) between 2015 and June 2022.

The results demonstrate the influential aspects of spillovers between Islamic and conventional financial markets, including the leading authors, journals, countries and institutions and the intellectual aspects of literature. These aspects are synthesised into four main streams: research between stock indexes; studies between stock indexes, oil and precious metal; works between Sukuk, bond and indexes; and empirical studies review. The authors also propose future research directions in spillovers between Islamic and conventional financial markets.

Our study is subject to several limitations. Firstly, the authors only used the WoS database. Secondly, the study only includes papers and reviews written in English from the WoS. This study assists academic scholars, practitioners and regulatory bodies in further exploring the suggested issues in future studies and improving and predicting economic and financial stability.

To the best of the authors’ knowledge, no extant empirical studies have been conducted in this area of research interest.

The problem of motif discovery has become a significant challenge in the era of big data where there are hundreds of genomes requiring annotations. The importance of motifs has led many researchers to develop different tools and algorithms for finding them. The purpose of this paper is to propose a new algorithm to increase the speed and accuracy of the motif discovering process, which is the main drawback of motif discovery algorithms.

All motifs are sorted in a tree-based indexing structure where each motif is created from a combination of nucleotides: ‘A’, ‘C’, ‘T’ and ‘G’. The full motif can be discovered by extending the search around 4-mer nucleotides in both directions, left and right. Resultant motifs would be identical or degenerated with various lengths.

The developed implementation discovers conserved string motifs in DNA without having prior information about the motifs. Even for a large data set that contains millions of nucleotides and thousands of very long sequences, the entire process is completed in a few seconds.

Experimental results demonstrate the efficiency of the proposed implementation; as for a real-sequence of 1,270,000 nucleotides spread into 2,000 samples, it takes 5.9 s to complete the overall discovering process when the code ran on an Intel Core i7-6700 @ 3.4 GHz machine and 26.7 s when running on an Intel Xeon x5670 @ 2.93 GHz machine. In addition, the authors have improved computational performance by parallelizing the implementation to run on multi-core machines using the OpenMP framework. The speedup achieved by parallelizing the implementation is scalable and proportional to the number of processors with a high efficiency that is close to 100%.

The purpose of this paper is twofold: first to carry out a comprehensive literature review for state of the art regarding airline schedule planning and second to identify some new research directions that might help academic researchers and practitioners.

The authors mainly focus on the research work appeared in the last three decades. The search process was conducted in database searches using four keywords: “Flight scheduling,” “Fleet assignment,” “Aircraft maintenance routing” (AMR), and “Crew scheduling”. Moreover, the combination of the keywords was used to find the integrated models. Any duplications due to database variety and the articles that were written in non-English language were discarded.

The authors studied 106 research papers and categorized them into five categories. In addition, according to the model features, subcategories were further identified. Moreover, after discussing up-to-date research work, the authors suggested some future directions in order to contribute to the existing literature.

The presented categories and subcategories were based on the model characteristics rather than the model formulation and solution methodology that are commonly used in the literature. One advantage of this classification is that it might help scholars to deeply understand the main variation between the models. On the other hand, identifying future research opportunities should help academic researchers and practitioners to develop new models and improve the performance of the existing models.

This study proposed some considerations in order to enhance the efficiency of the schedule planning process practically, for example, using the dynamic Stackelberg game strategy for market competition in flight scheduling, considering re-fleeting mechanism under heterogeneous fleet for fleet assignment, and considering the stochastic departure and arrival times for AMR.

In the literature, all the review papers focused only on one category of the five categories. Then, this category was classified according to the model formulation and solution methodology. However, in this work, the authors attempted to propose a comprehensive review for all categories for the first time and develop new classifications for each category. The proposed classifications are hence novel and significant.

The purpose of this paper is to present a model to predict the micro-hardness of friction stir processed (FSPed) AZ31B magnesium alloy using response surface methodology (RSM). Another objective is to identify process parameters and through-thickness position which will give higher micro-hardness values. Moreover, the study aims at defining the factor that exhibits the most effect on the micro-hardness. Friction stir processing (FSP) machine can then be fed with the optimized parameters to achieve desirable properties.

An experimental setup was designed to conduct FSP. Several AZ31B magnesium samples were FSPed at different combinations of rotational and translational speeds. The micro-hardness of all the combinations of process parameters was measured at different through-thickness positions. This was followed by an investigation of the three factors on the resulting micro-hardness. RSM was then used to develop a model with three factors and three levels to predict the micro-hardness of FSPed AZ31 magnesium alloy within the covered range. The analyses of variance in addition to experimental verification were both used to validate the model. This was followed by an optimization of the response.

The model showed excellent capability of predicting the micro-hardness values as well as the optimum values of the three factors that would result in better micro-hardness. The model was able to capture the effects of rotational speed, translational speed, and through-thickness position. Results suggest that micro-hardness values were mostly sensitive to changes in tool rotational speed.

FSP is considered to be one of the advanced microstructural modification techniques which is capable of enhancing the mechanical properties of light-weight alloys. However, the lack of accurate models which are capable of predicting the resulted properties from process parameters hinders the widespread utilization of this technique. At the same time, RSM is considered as a vital branch of experimental design due to its ability to develop new processes and optimize their performance. Hence, the developed model is very beneficial and is meant to save time and experimental effort toward effective use of FSP to get the desired/optimum micro-hardness distribution.

This study aims to investigate the dependence structure and volatility spillovers among two strategic commodities (crude oil and gold) and a set of Islamic and conventional regional stock market indices, while examining the Ramadan effect

The empirical strategy consists of two complementary measures of dependence and connectedness. This study first uses copulas to examine the dependency between the markets considered, then spillovers compute the magnitude of the connectedness among them.

The copulas analysis shows that Frank’s copula appears to better capture the relationship between most asset returns and highlights the almost absence of extreme dependence and, therefore, the existence of diversification opportunities. Moreover, the connectedness analysis suggests that gold is a net volatility receiver and provides, thereby, greater diversification benefits compared to crude oil. In addition, the high levels of time-varying connectedness support strong integration among the financial markets studied, specifically during the COVID-19 crisis period. Furthermore, the connectedness among the markets studied increases during the Ramdan subperiods, supporting shift contagion among financial markets considered during this religious holiday.

The results provide investors with a better understanding of the nature as well as the magnitude of the interdependences between commodity markets and a set of Islamic and conventional regional stock markets. Indeed, it is of paramount importance for investors to clearly understand how Islamic and conventional markets are segmented or integrated during stress and stress-free periods, as well as the effect of the month of Ramadan on the interdependence among markets, to better assess risks, diversify portfolios and implement more effective hedging strategies.

While a considerable body of literature examines financial contagion and volatility transmission between financial markets, there is still much to be said regarding connectedness among commodity and stock markets, particularly when it comes to studying the effects of religious holidays on the interaction between conventional and Islamic assets. This paper fills in this gap by focusing on the dependence structure as well as the connectedness between Islamic stock indices, conventional stock indices, gold and crude oil for six different regions, while examining the Ramadan effect.

Airline scheduling is an extremely complex process. Moreover, disruption in a single flight may damage the entire schedule tremendously. Using an efficient recovery scheduling strategy is vital for a commercial airline. The purpose of this paper is to present an integrated aircraft and crew recovery plans to reduce delay and prevent delay propagation on airline schedule with the minimum cost.

A mixed-integer linear programming model is proposed to formulate an integrated aircraft and crew recovery problem. The main contribution of the model is that recovery model is formulated based on individual flight legs instead of strings. This leads to a more accurate schedule and better solution. Also, some important issues such as crew swapping, reassignment of aircraft to other flights as well as ground and sit time requirements are considered in the model. Benders’ decomposition approach is used to solve the proposed model.

The model performance is also tested by a case including 227 flights, 64 crew, 56 aircraft and 40 different airports from American Airlines data for a 24-h horizon. The solution achieved the minimum cost value in 35 min. The results show that the model has a great performance to recover the entire schedule when disruption happens for random flights and propagation delay is successfully limited.

The authors confirm that this is an original paper and has not been published or under consideration in any other journal.