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The purpose of this paper is to focus on challenges faced by longitudinal quantitative analyses of school improvement processes and offers a systematic literature review of current papers that use longitudinal analyses. In this context, the authors assessed designs and methods that are used to analyze the relation between school improvement processes and student outcomes. Based on this the authors point out to what extent the papers consider different aspects of the complex nature of school improvement (e.g. multilevel structure, indirect and nonlinear effects, reciprocity). The choice of study designs and methods of analysis substantially determines which aspects of this complexity are taken into account.

The authors searched in four international high-impact journals and in ERIC for articles reporting longitudinal school improvement studies. The database of the review consisted of a total of 428 journal articles. In total, 13 of the 428 papers met the selection criteria and were analyzed in detail.

The analyzed papers use a wide range of designs and methodological approaches. They support the assumption that sophisticated quantitative longitudinal designs and methods can be applied effectively in school improvement research. However, considering the complexity of school improvement is accompanied by high demands on designs and methods. Due to this none of the papers met the standards applied in this review completely.

In particular, further research is needed to consider a long period of observation, reciprocal indirect and nonlinear processes in a multilevel structure. Moreover, research is required for a better and unambiguous theoretical foundation and empirical validation of the number of and intervals between measurement points.

If more consideration is given to the complex nature of school improvement in future studies, the broader knowledge base will allow a better understanding of the dynamic relation of school improvement and student learning. It would thus be possible to make more appropriate recommendations for the support of school improvement practice.

The original contribution of the paper is to show which aspects of the complexity of school improvement processes – and to what extent – are currently addressed in designs and methods of analysis applied in quantitative longitudinal studies that investigate the relation between schools’ capacity to managing change and student outcomes. Additionally the authors aim at deriving need for further research and giving guidelines how designs and methods in further studies can reflect the complexity appropriately. It is highly important to consider all aspects of this complexity to describe and understand the dynamic relation of school improvement processes and student outcomes.

In this chapter, the authors consider the role of time for research in occupational stress and well-being. First, temporal issues in studying occupational health longitudinally, focusing in particular on the role of time lags and their implications for observed results (e.g., effect detectability), analyses (e.g., handling unequal durations between measurement occasions), and interpretation (e.g., result generalizability, theoretical revision) were discussed. Then, time-based assumptions when modeling lagged effects in occupational health research, providing a focused review of how research has handled (or ignored) these assumptions in the past, and the relative benefits and drawbacks of these approaches were discussed. Finally, recommendations for readers, an accessible tutorial (including example data and code), and discussion of a new structural equation modeling technique, continuous time structural equation modeling, that can “handle” time in longitudinal studies of occupational health were provided.

This paper covers different types of research designs, like, longitudinal, cross-section and sequential design, experimental design (including factorial experimental design), and correlational design, with illustrative examples. This paper will help a scholar to know how choice of research design depends on a number of parameters, highlighted by author.

The purpose of this paper is to find an omnidirectional robust gust response stabilization (GRS) scheme with anti-disturbance and state-limited features.

Disturbance observer and barrier Lyapunov techniques, which can, respectively, estimate the lumped disturbances of the dynamic system in real-time and ensure the middle states within some prescribed ranges according to some flight safety indexes.

In the existing literature, almost all of the GRS controllers are either only for the longitudinal dynamics or only for the latitudinal dynamics. Few studies have considered the gust response alleviation problem with omnidirectional wind disturbance and full aircraft model.

This paper proposes a fresh scheme to deal with a more holistic GRS problem; the disturbance observer based (DOB) barrier Lyapunov backstepping longitudinal controller has been put forward; DOB nonlinear dynamic inversion to handle the multi-input-multi-output lateral dynamics; and to closely connect the two loops of the latitudinal dynamics, a manipulating variable conversion method is proposed.

The purpose of this study is to extend previous research by using a longitudinal design to examine the differential contribution of brand understanding (BU) drivers at various moments in the early tenure of service employees. Employee BU is a prerequisite of brand promise delivery among service employees. Previous studies, using cross-sectional samples, established that brand-oriented recruitment, training and leadership are significant BU drivers.

A three-wave survey was collected from a 105-member panel of recent hires at a restaurant chain that displayed a strong brand culture and adopted internal brand management (IBM) practices. Structural equation models with carryover effects were estimated to measure the impact of BU drivers on Day 1, as well as at four and seven months of tenure. In addition, a latent growth model of BU was estimated using random coefficients modeling.

Results show a significant positive effect of IBM practices on BU at each point in time; however, despite this, by the seven month milestone, BU is still not fully developed.

As with most organizational longitudinal studies, there was sample attrition because of the high turnover that characterizes the restaurant industry. This attrition is not believed to be correlated with the variables measured in the study.

Managers seeking a differentiated customer experience should not assume new hires attain a good understanding of the service brand even after the first seven months of tenure. Hence, brand training and leadership should extend well beyond this time frame.

This study is the first, as per the authors’ understanding, to use a longitudinal design to model BU as a dynamic variable because it befits the learning trajectories of new employees.

This paper aims to present the design of a stability augmentation system (SAS) in the longitudinal and lateral axes for an unstable helicopter.

The feedback controller is designed using linear quadratic regulator (LQR) control with full state feedback and LQR with output feedback approaches. SAS is designed to meet the handling qualities specification known as Aeronautical Design Standard (ADS‐33E‐PRF). A helicopter having a soft inplane four‐bladed hingeless main rotor and a four‐bladed tail rotor with conventional mechanical controls is used for the simulation studies. In the simulation studies, the helicopter is trimmed at hover, low speeds and forward speeds flight conditions. The performance of the helicopter SAS schemes are assessed with respect to the requirements of ADS‐33E‐PRF.

The SAS in the longitudinal axis meets the requirement of the Level 1 handling quality specifications in hover and low speed as well as for forward speed flight conditions. The SAS in the lateral axis meets the requirement of the Level 2 handling quality specifications in both hover and low speed as well as for forward speed flight conditions. The requirements of the inter axis coupling is also met and shown for the coupled dynamics case. The SAS in lateral axis may require an additional control augmentation system or adaptive control to meet the Level 1 requirements.

The study shows that the design of a SAS using LQR control algorithm with full state and output feedbacks can be used to meet ADS‐33 handling quality specifications.

This research aims to investigate how entrepreneurial orientation influences a firm’s differentiation–cost advantage ambidexterity (DCAA) and performance indirectly through dynamic capabilities, while also investigating the impact of the interactive effect of the level and consistency of entrepreneurial orientation on dynamic capabilities. The goal of this study is to better understand the importance of consistently following an entrepreneurial orientation, as well as the linkage of such a consistently implemented strategy upon gaining both a cost and differentiation positioning enhancement.

Two empirical studies are conducted to test the proposed hypotheses – one longitudinal with multiple forms of data (i.e. text data, survey data and archival data) from 100 Taiwanese electronics firms and the other using primary data from a survey of senior managers.

Entrepreneurial orientation improves dynamic capabilities, which in turn promote superior DCAA and enhanced firm performance. In addition, as captured through a unique measure of consistency allowed through computer-aided text analysis, the results indicate that the effect of entrepreneurial orientation on dynamic capabilities is amplified when a firm consistently adopts entrepreneurial decisions and actions.

The specific context was a sample of electronics firms in Taiwan. This limits the generalization of findings, as would be possible with assessing the hypotheses in other industries.

This research clearly demonstrates the significance of consistency in pursuing a strategic orientation. The consistent support and deployment of resources facilitates an organization’s achieving positive outcomes associated with an entrepreneurial orientation.

While entrepreneurial orientation contributes to firm performance, extant knowledge on the internal process through which entrepreneurial orientation affects performance is relatively limited. The findings not only highlight the full mediating role of dynamic capabilities and DCAA, but also shed light on the importance of consistency in entrepreneurial orientation over time.

The purpose of this paper is to develop a directional and roll control system for unmanned combat air vehicle (UCAV) automatic takeoff roll, with the objective of keeping the UCAV along the runway centerline and keeping the wings level, especially when there is a crosswind.

The nonlinear model of the UCAV during takeoff roll is established. The model is linearized about the lateral‐directional equilibrium point at different forward speeds. The approximate directional model and roll model are extracted using time‐scale decomposition technique. Then the directional control law and roll control law are developed using gain scheduling approach. Nose wheel steering, differential brake and rudder are used as the primary directional control device at low, medium and high speeds, respectively, according to both the qualitative and quantitative analysis of their control effectiveness at different speeds. A priority matrix is developed to determine the secondary control device which is used if the primary control device fails, thus the directional control system can have a certain degree of fault tolerance.

This work developed the directional control law and roll control law by using gain scheduling approach. Experimental results verified that the developed directional and roll control system has high robustness and satisfactory fault tolerance: it can guarantee a safe takeoff under a 50 ft/sec crosswind, even if one directional control device fails, which satisfies the relevant criteria in MIL‐HDBK‐1797.

The directional and roll control system developed can be easily applied to practice and can steer the UCAV during takeoff roll safely, which will considerably increase the autonomy of the UCAV.

The paper shows how time‐scale decomposition technique is employed to extract the approximate directional model and roll model, which simplifies model analysis and control law design. A fault‐tolerant directional control system is designed to improve safety during takeoff.

The purpose of this paper is to outline the various research methods adopted by researchers in studies that have investigated the relationship between human resource management (HRM) practices and organizational commitment (OC).

The authors adopted a comprehensive review that covers empirical research on HRM-OC relationship, which was published between 2001 and 2016 in international peer-reviewed journals. A total of 63 empirical studies were included in this review. Authors adopted content analysis to synthesize the findings on the adopted research methods.

This review clearly indicates the excessive reliance of researchers on specific research methods (i.e. surveys, individual-level analysis, and cross-sectional design). However, there is a steady increase in empirical studies that have adopted mixed-method, multi-actor, and multi-level research designs.

This review has attempted to explore advanced research methods that may offer assistance to overcome methodological limitations of the current HRM-OC literature.