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The purpose of this paper is to build a neural model of an aircraft from flight data and online estimation of the aerodynamic derivatives from established neural model.

A neural model capable of predicting generalized force and moment coefficients of an aircraft using measured motion and control variable is used to extract aerodynamic derivatives. The use of neural partial differentiation (NPD) method to the multi-input-multi-output (MIMO) aircraft system for the online estimation of aerodynamic parameters from flight data is extended.

The estimation of aerodynamic derivatives of rigid and flexible aircrafts is treated separately. In the case of rigid aircraft, longitudinal and lateral-directional derivatives are estimated from flight data. Whereas simulated data are used for a flexible aircraft in the absence of its flight data. The unknown frequencies of structural modes of flexible aircraft are also identified as part of estimation problem in addition to the stability and control derivatives. The estimated results are compared with the parameter estimates obtained from output error method. The validity of estimates has been checked by the model validation method, wherein the estimated model response is matched with the flight data that are not used for estimating the derivatives.

Compared to the Delta and Zero methods of neural networks for parameter estimation, the NPD method has an additional advantage of providing the direct theoretical insight into the statistical information (standard deviation and relative standard deviation) of estimates from noisy data. The NPD method does not require the initial value of estimates, but it requires a priori information about the model structure of aircraft dynamics to extract the flight stability and control parameters. In the case of aircraft with a high degree of flexibility, aircraft dynamics may contain many parameters that are required to be estimated. Thus, NPD seems to be a more appropriate method for the flexible aircraft parameter estimation, as it has potential to estimate most of the parameters without having the issue of convergence.

This paper highlights the application of NPD for MIMO aircraft system; previously it was used only for multi-input and single-output system for extraction of parameters. The neural modeling and application of NPD approach to the MIMO aircraft system facilitate to the design of neural network-based adaptive flight control system. Some interesting results of parameter estimation of flexible aircraft are also presented from established neural model using simulated data as a novelty. This gives more value addition to analyzing the flight data of flexible aircraft as it is a challenging problem in parameter estimation of flexible aircraft.

The purpose of this paper is to investigate the estimation methodology with a highly generalized cost-effective single hidden layer neural network.

The aerodynamic parameter estimation is a challenging research area of aircraft system identification, which finds various applications such as flight control law design and flight simulators. With the availability of the large database, the data-driven methods have gained attention, which is primarily based on the nonlinear function approximation using artificial neural networks. A novel single hidden layer feed-forward neural network (FFNN) known as extreme learning machine (ELM), which overcomes the issues such as learning rate, number of epochs, local minima, generalization performance and computational cost, as encountered in the conventional gradient learning-based FFNN has been used for the nonlinear modeling of the aerodynamic forces and moments. A mathematical formulation based on the partial differentiation is proposed to estimate the aerodynamic parameters.

The real flight data of longitudinal and lateral-directional motion have been considered to estimate their respective aerodynamic parameters using the proposed methodology. The efficacy of the estimates is verified with the results obtained through the conventional parameter estimation methods such as the equation-error method and filter-error method.

The present study is an outcome of the research conducted on ELM for the estimation of aerodynamic parameters from the real flight data. The proposed method is capable to estimate the parameters in the presence of noise.

The purpose of this paper is to analyse the interaction between a profit maximising mortgagor and a newcomer to a mortgage market with Bertrand competition where the newcomer has a populistic entry strategy and undercuts mortgage market rates. The intention of the paper is to relate the populistic entry strategy to mortgage market characteristics and the strategic market position of both the established mortgagor and the newcomer in question.

The paper analyses a mortgage market by combining the behaviour of a profit maximising mortgagor with that of a newcomer to the mortgage market which has a populistic entry strategy and does not maximise profits. The short-run market solution provides comparative statics on the strategic market position of both the established mortgagor and the newcomer to the mortgage market during the entry phase both related to product differentiation and to price mirroring and undercutting of mortgage rates.

The model finds a mortgage market solution where a lower mortgage rate helps the newcomer gain a customer base. As the newcomer's strategy to mirror prices makes it unable to pass-through funding cost to its mortgage rate, the strategy is unsustainable over time. The established mortgagor has a strategically beneficial position as the mortgage market rates only relate to its funding cost. Unless the newcomer has a funding cost advantage, the established mortgagor has a higher interest rate margin. Differentiation impacts the newcomers’ interest rate margin positively. If the newcomer lacks a funding cost advantage, there is a critical mirroring rate that ensures it a higher interest rate margin. The higher the newcomers’ own funding cost, the higher is the upper bound for price mirroring, relating market entry to a small undercutting of mortgage rates and a mortgage market with weak competition. The funding cost of the established mortgagor pulls pricing in the opposite direction, allowing for a lower mirroring rate and tougher mortgage market competition during entry.

The paper aims to contribute to the understanding of market equilibrium in the absence of profit maximising behaviour. Framing a mortgage market in terms of a duopoly where a newcomer enters with a populistic entry strategy offering a lower mortgage rate and a mortgage product with a different loan-to-value (LTV) ratio, a novel mortgage market case comes about. The populistic entry strategy produces an augmented reaction curve, crucial for the mortgage market rates.

The purpose of this paper is to provide an organizing lens for viewing the distinct contributions to knowledge production from those research communities addressing the impact of competitive strategy on company performance in general, and the influence of cost leadership and differentiation strategy on organizational performance in detail.

The research methodology was based on the PRISMA review, and thematic analysis based on an iterative process of open coding was analyzed and then the sample was analyzed by illustrating the research title, objectives, method, data analysis, sample size, variables and country.

The main factor that influenced the competitive strategy is strategic growth; strategic growth has a significant influence on competitive strategy. Furthermore, competitive strategy will boost firm network, performance measurement and organization behavior. In the same way, the internal goal factor will enhance organizational effectiveness. Also, a differentiation strategy will support management practice factors, strategic positions, product price, product characteristics and company performance.

This study contributes to the literature by identifying a framework of competitive strategy factors, company performance factors, cost leadership strategy factors, differentiation strategy factors and competitive strategy with global market factors. This study provides a complete picture and description of the resulting body knowledge in competitive strategy and organizational performance.

Topology optimization is a method used for developing optimized geometric designs by distributing material pixels in a given design space that maximizes a chosen quantity of interest (QoI) subject to constraints. The purpose of this study is to develop a problem-agnostic automatic differentiation (AD) framework to compute sensitivities of the QoI required for density distribution-based topology optimization in an unstructured co-located cell-centered finite volume framework. Using this AD framework, the authors develop and demonstrate the topology optimization procedure for multi-dimensional steady-state heat conduction problems.

Topology optimization is performed using the well-established solid isotropic material with penalization approach. The method of moving asymptotes, a gradient-based optimization algorithm, is used to perform the optimization. The sensitivities of the QoI with respect to design variables, required for optimization algorithm, are computed using a discrete adjoint method with a novel AD library named residual automatic partial differentiator (Rapid).

Topologies that maximize or minimize relevant quantities of interest in heat conduction applications are presented. The efficacy of the technique is demonstrated using a variety of realistic heat transfer applications in both two and three dimensions, in conjugate heat transfer problems with finite conductivity ratios and in non-rectangular/non-cuboidal domains.

In contrast to most published work which has either used finite element methods or Cartesian finite volume methods for transport applications, the topology optimization procedure is developed in a general unstructured finite volume framework. This permits topology optimization for flow and heat transfer applications in complex design domains such as those encountered in industry. In addition, the Rapid library is designed to provide a problem-agnostic pathway to automatically compute all required derivatives to machine accuracy. This obviates the necessity to write new code for finding sensitivities when new physics are added or new cost functions are considered and permits general-purpose implementations of topology optimization for complex industrial applications.

This paper aims to present a new method for the approximate solution of two-dimensional nonlinear Volterra–Fredholm partial integro-differential equations with boundary conditions using two-dimensional Chebyshev wavelets.

For this purpose, an operational matrix of product and integration of the cross-product and differentiation are introduced that essentially of Chebyshev wavelets. The use of these operational matrices simplifies considerably the structure of the computation used for a set of the algebraic system has been obtained by using the collocation points and solved.

Theorem for convergence analysis and some illustrative examples of using the presented method to show the validity, efficiency, high accuracy and applicability of the proposed technique. Some figures are plotted to demonstrate the error analysis of the proposed scheme.

This paper uses operational matrices of two-dimensional Chebyshev wavelets and helps to obtain high accuracy of the method.

The purpose of this paper is to investigate the mediating role of comprehensive performance measurement systems (PMS) – i.e. measurement systems that comprise financial and non-financial indicators, and which also consist of indicators related to different aspects of an organisation’s operations – in the relationship between strategy and company performance.

Survey data of top managers of large European companies were collected and analysed by means of exploratory factor analyses and hierarchical regressions in order to validate the proposed hypotheses.

This research shows that different strategies lead to the use of different types of performance indicators. Also, it finds that the utilisation of a comprehensive PMS enables the implementation of both differentiation and cost-leadership strategies. Specifically, a comprehensive PMS positively mediates the effect of differentiation strategy on organisational and innovative performance, and of cost-leadership strategy on organisational performance.

Further research could be undertaken in other contexts and consider additional factors, such as the structure, maturity and different uses of PMS, and the cost of measuring performance. Qualitative studies could examine the role of PMS in dynamic environments, as well as the evolution of PMS during strategic transitions.

Greater consideration should be given to the utilisation of different types of performance indicators when implementing and re-formulating strategy.

This study clarifies the links between strategy and performance measurement, and it is the first to identify the mediating effect of comprehensive PMS between strategy and company performance.

In the shadow of X‐ray tomography and nuclear magnetic resonance tomography a new tomographic technique based on low‐frequency electric currents has been successfully developed in the past decade. Impedance computed tomography (ICT), although it gives poor spatial resolution images, is unmatched in certain cases. Two different approaches to the sensitivity analysis are presented in this paper. The direct differentiation method has been applied, but the adjoint variable method has not been used in ICT reconstruction algorithms until now. Some problems associated with the adjoint variable method of sensitivity analysis are discussed. The new algorithm is compared with the direct differentiation approach.

Considering the significant contribution of service sector of the whole contribution of the economics, this study aims to investigate the impact of strategic performance measurement sytstem (SPMS) on sustainability strategic outcomes in the industry through organizational learning and service strategic alignment.

Using a survey study, 158 usable data were analysed using SmartPLS.

The results show that service strategic alignment and organizational learning mediate the relationship between SPMS and performance for product differentiation companies. For cost leadership companies, the results indicate that there is no mediation of service strategic alignment and organizational learning on the relationship between SPMS and performance.

This study first provides evidence that SPMS improves performance through service strategic alignment and organizational learning for product differentiation companies in which innovation is crucial to thrive and succeed. Second, it introduces to the literature the characteristics of SPMS.

New insights of implementation of SPMS in improving companies’ performance in Indonesian financial institutions are provided.

Two concurrent changes are raising questions about the interplay between armed forces and local governments in contemporary urban settings. The first one is the spatial reorganisation of armed forces that has been taking place in most European countries since the end of the Cold War. The second one is the redistribution of political authority between levels of governments that has increased the relevance of cities and transformed urban governance. The chapter conceptualises the military administration as an urban actor, whose material and symbolic resources in cities transform over time. It investigates both the effects of a (changing) military presence on urban policies, and how those changes are framed and managed by local governments. The case under consideration is the city of Taranto (Southern Italy), one among the biggest military ports on the Mediterranean Sea. Here, transformations of defence policies opened a window of opportunity for a new urban policy agenda, whose goal is a partial differentiation from military activities. During the last ten years, local political elites have been undertaking several strategies for military spaces redevelopment. However, uneven power relations prevent civilian-military bargain: redevelopment strategies are the result of either local military initiative or central State decisions.