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Understanding the performance and flight envelope of a damaged aircraft is a preliminary requirement to recover the aircraft after damage. This paper aims to provide a comprehensive understanding of wing damage effect on airplane performance, local stability, and flying quality of each trim state inside the achievable flight envelope.

This paper demonstrates the use of attainable equilibrium points which are referred as trim states in order to estimate a damaged airplane manoeuvring flight envelope using a numerical computation method.

Wing damaged airplane manoeuvring flight envelope is estimated for different portions of the wing tip loss. Local stability at each trim condition inside the estimated flight envelope is analysed, and also motion flight modes and flying quality sensitivity to the wing damage are explored.

Local stability and flying quality analysis at each trim condition inside the flight envelope which demonstrate the effect of damage provides a criterion to prioritize the choice of trimmed flight condition as motion primitives for the airplane post‐damage flight and safe landing.

Decreasing revenues among local governments across the country have placed an increased focus on governmental financial practices. For states with local government financial oversight organizations, the ratios and other benchmarks used to assess fiscal stability face increased scrutiny. This study examines financial reports sent to North Carolina’s financial oversight body, the Local Government Commission (LGC), to determine the types of operational and policy practices that can lead to fiscal stress based on guidelines established by the LGC. Findings indicate that lowering levels of fund balance, increased salaries, increased debt service levels, and the presence of a countywide water system all increased the probability of a county government receiving notice of potential financing problems requiring immediate action.

The purpose of this paper is to evaluate the impact of the Law on Budgetary Stability of 2012 over the level of accumulated debt in Spanish municipalities. The paper also analyses the influence of the socioeconomic environment, political factors and budgetary indicators on the level of accumulated debt for the 2008–2014 period, which coincides with the economic crisis.

The paper uses panel data methodology. First, the t-test of difference of means is used to analyse which political variables are significant. Then, the analysis is carried out using the generalised method of moments in order to obtain the explanatory variables of the level of debt.

The results show that in 2013–2014, the Law on Budgetary Stability did not have a significant effect on reducing the accumulated debt. However, the law has led to a change of the trend in debt levels, as the debt decreased from 2013 to 2014. Moreover, population, unemployment, immigration, personnel expenditure, direct fiscal pressure and level of investment have an influence over the level of accumulated debt.

This paper contributes to analyse to what extent the Law on Budgetary Stability has affected accumulated debt. The study reveals a slight impact on reducing debt, although it is not significant. An original aspect of this paper is that it uses dynamic models to study the accumulated debt of Spanish municipalities. The study shows the impact of socioeconomic, environmental and political factors as well as of budgetary indicators on the level of debt in the context of economic crisis.

En este artículo se analiza el impacto que tiene la normativa de estabilidad presupuestaria española del año 2012 en el nivel de deuda acumulada de los municipios españoles. También se contrasta la influencia del entorno socioeconómico, político y presupuestario en el nivel de deuda viva durante el periodo 2008-2014 que coincide con la crisis económica.

Para alcanzar los objetivos, se utiliza la metodología de datos de panel. En primer lugar, se realiza un test de medias por el cual se descartan las variables políticas no significativas. Posteriormente, se plantea el Método Generalizado de Momentos (GMM) para obtener las variables explicativas del endeudamiento.

Se evidencia que durante el periodo 2013-2014, la normativa de estabilidad no ha tenido un efecto significativo en la reducción de la deuda viva. No obstante, la legislación ha permitido cambiar la tendencia del nivel de deuda, ya que durante 2013-2014 el endeudamiento se redujo. Además, se constata que la población, el desempleo, la inmigración, la concentración política, los gastos de personal, la presión fiscal y la inversión influyen en el endeudamiento.

La aportación de este trabajo radica en analizar en qué medida ha repercutido la normativa de estabilidad presupuestaria en el nivel de deuda viva. Se ha evidenciado un ligero impacto en la reducción de endeudamiento, aunque no es significativo. Resulta original la aplicación de modelos dinámicos en el estudio de la deuda viva española. Asimismo, se establece el impacto que tienen los factores del entorno político, socioeconómico y presupuestario en un entorno de crisis económica.

The purpose of this paper is to use the internal model control to deal with nonlinear stable systems affected by parametric uncertainties.

The dynamics of a considered system are approximated by a Takagi-Sugeno fuzzy model. The parameters of the fuzzy rules premises are determined manually. However, the parameters of the fuzzy rules conclusions are updated using the descent gradient method under inequality constraints in order to ensure the stability of each local model. In fact, without making these constraints the training algorithm can procure one or several unstable local models even if the desired accuracy in the training step is achieved. The considered robust control approach is the internal model. It is synthesized based on the Takagi-Sugeno fuzzy model. Two control strategies are considered. The first one is based on the parallel distribution compensation principle. It consists in associating an internal model control for each local model. However, for the second strategy, the control law is computed based on the global Takagi-Sugeno fuzzy model.

According to the simulation results, the stability of all local models is obtained and the proposed fuzzy internal model control approaches ensure robustness against parametric uncertainties.

This paper introduces a method for the identification of fuzzy model parameters ensuring the stability of all local models. Using the resulting fuzzy model, two fuzzy internal model control designs are presented.

The purpose of this paper is to clarify a number of important facts about info‐gap decision theory.

Theorems are put forward to rebut claims made about info‐gap decision theory in papers published in this journal and elsewhere.

Info‐gap's robustness model is a simple instance of the most famous model in classical decision theory for the treatment of decision problems subject to severe uncertainty, namely Wald's maximin model. This simple instance is the equivalent of the well‐established model known universally as radius of stability. Info‐gap's robustness model has an inherent local orientation. Therefore, it is in principle unable to address the fundamental difficulties presented by the type of severe uncertainty that is postulated by info‐gap decision theory.

These findings caution against accepting the assertions made in the info‐gap literature about: info‐gap decision theory's role and place in decision making under severe uncertainty; and its ability to model, analyze, and manage severe uncertainty.

This paper exposes the serious difficulties with claims made in papers published in this journal and elsewhere regarding the place and role of info‐gap decision theory in decision theory and its ability to handle severe uncertainty.

The recent recession provides us a good window to reveal fiscal problems and inadequate preparations of state and local governments. To address the fiscal crisis, and more importantly, to prepare for the potential economic downturns, this paper designs a framework of necessary tools to combat fiscal crisis. With matching policies of revenue diversification and counter-cyclical fiscal policy (CCFP), debt financing can be used as an effective tool to help state and local governments pull through fiscal crises. A brief example of local governments in Georgia proves the possibility and effectiveness of the counter-cyclical debt policy. It will be much better to institutionalize these policies to avoid the moral hazards of governments and politicians, which, in a great sense, requires engaging and educating the public and, finally, obtaining support from them.

With the growing scale of power grids, integrated power grids often contain multiple areas. When the control centre of each regional grid conducts an assessment of local voltage stability, the calculation is always based on the local regional power grid model. However, less consideration is given to a detailed model of the entire network, which may lead to a large calculation error. Under the premise of ensuring the data and information security of Supervisory Control and Data Acquisition between different regional power grid operation control centres, the purpose of this paper is to reduce calculation error simply by using the data of a local power network.

According to the calculation methodology of “decomposition and coordination” and the power balance equation of an interconnected power grid, an improved radial equivalent independent (REI) equivalent method, which can reflect the dynamic characteristics of interconnected power grids to a certain extent, is proposed in this paper. A mathematical model of multi-area-grid L indicator synergic computing is derived as well.

With the calculation of Institute of Electrical and Electronics Engineers (IEEE) standard grids and an actual grid model, it is proven that the method proposed in this paper can significantly improve the accuracy of the regional power grid L indicator calculation and achieve the synergic computing of a multi-area power system L indicator, without an increase in data interaction among the regional power grids.

The indicator of voltage stability among multi-area was obtained by using the improved REI equivalent method with the change of the load participation factor. Particularly, the coordinated calculation method can be implemented on a local power grid without knowledge of all the parameters of its interconnection, which can avoid possible leakage of confidential data and information of the system owners.

The purpose of this paper is to develop growth models that depart from the conventional framework, in the sense that consumption decisions take into account previous periods' expectations about output fluctuations. Households will raise their propensity to consume in periods of expected expansion and they will lower it in phases of predictable recession. Such a framework allows discussion of how growth trends may be disturbed over time as the result of changes in consumer sentiment.

Endogenous growth models are generally designed to address long‐term trends of growth. They explain how the economy converges with or diverges from a balanced growth path and they characterize aggregate behavior, given the optimization problem faced by a representative agent that maximizes consumption utility. In such frameworks, only potential output matters and all decisions, by firms and households, are taken on the assumption that any expectations on the value of the output gap do not interfere with the agents' behavior. Introducing consumer sentiment, a conventional growth model is modified in order to understand how effective output eventually deviates from the balanced growth path.

The proposed framework allows one to introduce nonlinear dynamics into the model, making it feasible to obtain, for reasonable parameter values, endogenous fluctuations. These are triggered by a Neimark‐Sacker bifurcation.

By introducing consumer confidence or consumer sentiment, it is possible to integrate the evaluation of growth and cycles into a unified framework. It is possible to explain business cycles as the result of the consumers' reaction to the expected performance of the economic system.