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Understanding generational differences are important because generational diversity can affect work relationships and the effectiveness of communication, engagement and performance management strategies. On the other hand, organizations should be concerned about employee engagement, considering all the positive outcomes that engaged employees could bring to the workplace. The paper aims to discuss these issues.

The purpose of this study is to examine employee engagement of different generations in Iran. Four hypotheses were proposed regarding job engagement and its constructs: vigor, dedication and absorption. The study utilized ANOVA tests to detect statistically significant differences between generations.

The results revealed not only a number of significant differences among generations, but also some similarities. The study shows the value of generational analysis as a useful segmentation criterion in organizational behavior researches.

To distinguish between different generations in relation to job engagement, also better understanding the behavior of generational cohorts that affect the success of organizations. It helps managers to find and resolve the conflict among persons and groups in the organization and also to achieve the benefits of diversity, creativity and energy of generations.

The empirical studies of the options market efficiency have reported contradictory results, which sometimes confuse practitioners and academicians. The aim of this study was to clarify several aspects of options market efficiency by exploring the answers to two main questions: Under what conditions is the options market more efficient? Are the discrepancies in the estimated efficiency due to the reality of efficiency or mismeasurement?

Using a meta-analysis approach, 54 studies have been analyzed, which included 1,315 tests. The sum of the observations for all of the tests is 3.7 m observation sets. The effect size (type r) has been used to compare the different statistics in different studies. The cumulative effect size and its diversification have been calculated by the random effects model and Q statistic, respectively.

The most interesting finding of the study was that the options market, in all circumstances, is significantly inefficient. Another important finding was that the heterogeneity of options market efficiency is due to the complexity of pricing relations, test time, violation index and price type. To overcome this heterogeneity and accuracy, future studies should test the no-arbitrage options pricing relations at different times and by different price types, using complex and simple pricing relations and either mean violation or violation ratio efficiency measures.

Public disagreement about the options market efficiency in past studies means that this variable is heterogeneous in different conditions. As a significant contribution, this study develops the literature by proposing the causes of options market efficiency heterogeneity.

The purpose of this study is to meta-analytically compare the effect of differentiation strategy formulation on financial and non-financial performance to explore the agency problem.

This study was conducted using a meta-analysis approach and CMA2 software. Hypotheses has been tested using cumulative effect sizes. Then, the cumulative effect sizes if some subsamples are also tested for robustness check by manipulation of circumstances.

Based on the findings, differentiation affects performance dimensions. However, spite of shareholders’ wealth maximization, differentiation has a smaller effect on financial performance (as the proxy of shareholders’ wealth) compared with operational performance. Meanwhile, the robustness test showed that the results in all subcategories has also confirmed, and this supports the results.

The results catch attentions of shareholders to review the elements of management evaluation in the corporate governance system in a way that they focus more on stakeholders’ interests in developing differentiation strategy. Limitations of this study is firstly based on limitations of meta-analysis approach, which provide general results of relevant studies so that the local conditions of each firm should be considered in deploying implications.

Exploring the overall schema of firms (from past to present and in different research conditions) regarding the impact of differentiation strategy on performance has been the originality of this research because of potentials of meta-analysis against past field studies. This originality led to the discovery of the general confusion of firms in the development of differentiation strategy so that it emphasizes operational performance more than financial performance.

The purpose of this paper is to present the findings on jet array instabilities of molten caprolactam. Initial investigations showed that although a suitable range of parameters was found for stable jetting, there were cases where instabilities occurred due to external sources such as contamination.

The inkjet system consisted of a melt supply unit, filtration unit and printhead with pneumatic and thermal control. A start‐up strategy was developed to initiate the jetting trials. A digital microscope camera monitored the printhead nozzle plate to record the jet array stability within the recommended range of parameters from earlier research. The trials with jet instabilities were studied to analyse the instability behaviour.

It was found that instabilities occurred in three forms which were jet trajectory error, single jet failure and jet array failure. Occasionally, the jet with incorrect trajectory remained stable. When a jet failed, bleeding of melt from the nozzle due to the actuations influenced the adjacent jets initiating an array of jets to fail similar to falling dominos.

The research concept is novel and investigating the jet array instability behaviours could give an understanding on jetting reliability issues.

The purpose of this paper is to apply a hybrid neuro-fuzzy paradigm called self-organizing neuro-fuzzy multilayered classifier (SONeFMUC) to classify the operating faults of a hydraulic system. The main motivation behind the use of SONeFMUC is to attest the capabilities of neuro-fuzzy classifier for handling the difficulties associated with fault diagnosis of hydraulic circuits.

In the proposed methodology, first, the neuro-fuzzy nodes at each layer of the SONeFMUC are trained separately using two well-known bio-inspired algorithms, i.e. a semi deterministic method with random walks called co-variance matrix adaptation evolutionary strategy (CMA-ES) and a swarm-based explorer with adaptive fuzzified parameters (SBEAFP). Thereafter, a revised version of the group method data handling (GMDH) policy that uses the Darwinian concepts such as truncation selection and elitism is engaged to connect the nodes of different layers in an effective manner.

Based on comparative numerical experiments, the authors conclude that integration of neuro-fuzzy method and bio-inspired supervisor results in a really powerful classification tool beneficial for uncertain environments. It is proved that the method outperforms some well-known classifiers such as support vector machine (SVM) and particle swarm optimization-based SVM (PSO-SVM). Besides, it is indicated that an efficient bio-inspired method can effectively adjust the constructive parameters of the multi-layered neuro-fuzzy classifier. For the case, it is observed that designing a fuzzy controller for PSO predisposes it to effectively balance the exploration/exploitation capabilities, and consequently optimize the structure of SONeFMUC.

The originality of the paper can be considered from both numerical and practical points of view. The signals obtained through the data acquisition possess six different features in order for the hydraulic system to undergo four types of faults, i.e. cylinder fault, pump fault, valve leakage fault and rupture of the piping system. Besides, to elaborate on the authenticity and efficacy of the proposed method, its performance is compared with well-known rival techniques.

The purpose of this paper is to design an adaptive nonlinear controller for a nonlinear system of integrated guidance and control.

A nonlinear integrated guidance and control approach is applied to a homing, tail-controlled air vehicle. Adaptive backstepping controller technique is used to deal with the problem, and the Lyapanov theory is used in the stability analysis of the nonlinear system. A nonlinear model of normal force coefficient is obtained from an existing nonlinear model of lift coefficient which was validated by open loop response. The simulation was performed in the pitch plane to prove the benefits of the proposed scheme; however, it can be readily extended to all the three axes.

Monte Carlo simulations indicate that using nonlinear adaptive backstepping formulation meaningfully improves the performance of the system, while it ensures stability of a nonlinear system.

The proposed method could be used to obtain better performance of hit to kill accuracy without the expense of control effort.

A nonlinear adaptive backstepping controller for nonlinear aerodynamic air vehicle is designed and guaranteed to be stable which is a novel-based approach to the integrated guidance and control. This method makes noticeable performance improvement, and it can be used with hit to kill accuracy.

Previous research indicates that vitamin D and omega-3 co-supplementation may benefit overall health, but current evidence regarding its effects on lipid profile remains unclear. The present systematic review and meta-analysis aimed to examine the effects of vitamin D and omega-3 co-supplementation on lipid profile (total cholesterol [TC], low-density lipoprotein [LDL], triglyceride [TG] and high-density lipoprotein [HDL]) in adults.

In this systematic review and meta-analysis, relevant studies were obtained by searching the PubMed, Scopus and Web of Science databases (from inception to January 2022). Weighted mean differences and 95% confidence intervals were estimated via a random-effects model. Heterogeneity, sensitivity analysis and publication bias were reported using standard methods.

Pooled analysis of six randomized controlled trials (RCTs) revealed that vitamin D and omega-3 co-supplementation yielded significant reductions in TG (p = 0.631). A pooled analysis of five trials indicated a significant association between omega-3 and vitamin D treatment and reductions in TC (p = 0.001) and LDL (p = 0.001). Although, pooled analyses of omega-3 and vitamin D did not significantly affect HDL.

The findings suggest that vitamin D and omega-3 co-supplementation lowers TG, TC and LDL in adults. Future, large-scale, RCTs on various populations are needed to elucidate further beneficial effects of vitamin D and omega-3 co-supplementation on lipid profile and establish guidelines for clinical practice.

France is the third country in Europe after Italy and Spain for the number of employee-owned firms, with some 2,600 worker cooperatives (SCOPs). The authors propose a comprehensive review of SCOPs and any barriers to their expansion.

The authors analyse relevant legislation; review the rich empirical economic literature on SCOPs; and offer new descriptive empirical evidence comparing SCOPs and other French firms.

SCOPs benefit from a consistent legal framework and a well-structured and supportive cooperative movement. Cooperative laws allow attracting external capital, provide barriers against degeneration and encourage profit allocations that favour investment and labour. SCOPs are distributed across a wide range of industries; are larger than conventional firms, as capital intensive, more productive and survive better. Despite this good performance their number remains modest, perhaps because of information barriers.

An examination of the Italian and Spanish experiences and the relationship between SCOPs and the French labour movement might contribute to explaining the modest number of SCOPs.

The first comprehensive review of French worker cooperatives in four decades and the first with extensive comparative data on SCOPs and conventional French firms. With some of the best data on worker cooperatives in the world, findings have international relevance.

This paper could be considered as the first step of grounding the ambitions and speculations about hyper urban planning. In other words, it is just a brief approach for the critical discussion of hyper urban planning field, without too many details or long explanations, so further studying, arguing and additional future research should be done.

The scientific methodology is based on descriptive and analytical methods, in addition to case study method of data collection. Therefore, the paper has reviewed 16 case studies, which could arguably be lumped under the title of “hyper urban planning.”

The study focuses on proposing a new way to view urban planning, that is the hyper urban planning, which could be considered as a sort of specialized urban branch of advanced level, characterized by special criteria, which stimulates innovative and creative proposals for the future smart cities.

Hyper urban planning field generally aims to contribute to liberating and releasing the full creative imagination of the urban planners’ minds, outside the box and away from the exaggerated strict constraints.

The study has been based on theoretical aspects in addition to empirical experiments. The practical aspects reflect the potential and promising features of hyper urban planning, especially with regard to using creativity, sustainability and innovative technology solutions.

The paper’s analyses show that many hyper urban proposals have a high potential sustainability, environmentally, socially and economically.

As urban problems and built environment challenges have become more complex, the proposed vertical eco-cities under the umbrella of hyper urban planning field may arguably be promising and more sustainable urban solutions for the previously mentioned challenges.

The purpose of this paper is to present a nonlinear model along with stability analysis of a flexible supersonic flight vehicle system.

The mathematical state space nonlinear model of the system is derived using Lagrangian approach such that the applied force, moment, and generalized force are all assumed to be nonlinear functions of the system states. The condition under which the system would be unstable is derived and when the system is stable, the region of attraction of the system equilibrium state is determined using the Lyapunov theory and sum of squares optimization method. The method is applied to a slender flexible body vehicle, which is referenced by the other researchers in the literature.

It is demonstrated that neglecting the nonlinearity in external force, moment and generalized force, as it was assumed by other researchers, can cause significant variations in stability conditions. Moreover, when the system is stable, it is shown analytically here that a reduction in dynamic pressure can make a larger region of attraction, and thus instability will occur in a larger angle of attack, greater angular velocity and elastic displacement.

In order to carefully study the behavior of aeroelastic flight vehicle, a nonlinear model and analysis is definitely necessary. Moreover, for the design of the airframe and/or control purposes, it is essential to investigate region of attraction of equilibrium state of the stable flight vehicle.

Current stability analysis methods for nonlinear elastic flight vehicles are unable to determine the state space region where the system is stable. Nonlinear modeling affects the determination of the stability region and instability condition. This paper presents a new approach to stability analysis of the nonlinear flexible flight vehicle. By determining the region of attraction when the system is stable, it is demonstrated analytically, in this research, that decreasing the dynamic pressure can produce larger region of attraction.