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The purpose of this paper is to present a mathematical model of one very flexible transport category airplane whose structural dynamics was modeled with the strain-based formulation. This model can be used for the analysis of couplings between the flight dynamics and structural dynamics.

The model was developed with the use of Hamiltonian mechanics and strain-based formulation. Nonlinear flight dynamics, nonlinear structural dynamics and inertial couplings are considered.

The mathematical model allows the analysis of effects of high structural deformations on airplane flight dynamics.

The mathematical model has more than 60 degrees of freedom. The computational burden is too high, if compared to the traditional rigid body flight dynamics simulations.

The mathematical model presented in this work allows a detailed analysis of the couplings between flight dynamics and structural dynamics in very flexible airplanes. The better comprehension of these couplings will contribute to the development of flexible airplanes.

This work presents the application of nonlinear flight dynamics-nonlinear structural dynamics-strain-based formulation (NFNS_s) methodology to model the flight dynamics of one very flexible transport category airplane. This paper addresses also the way as the analysis of results obtained in nonlinear simulations can be made. Comparisons of the NFNS_s and nonlinear flight dynamics-linear structural dynamics methodologies are presented in this work.

The purpose of this paper is to study the effect of thermal treatment on the corrosion protection of steel by using poly(3-hexylthiophene) (P3HT) and P3HT/PS(polystyrene) or P3HT/PMMA(polymethyl methacrylate) blends coatings in sulfuric acid solution.

The polymer coatings were thermally treated at two different temperatures (100 and 200°C, respectively) and were compared with the polymer coatings dried at room temperature in their application as protective coatings against corrosion of A36 steel. The corrosion resistance of polymer coatings-covered steel substrates was evaluated by using potentiodynamic polarization curves and linear polarization resistance.

At 25 and 100°C, polymer coatings showed a better protection of the A36 steel, and the corrosion rate diminished in three orders of magnitude with regard to the bare steel. Morphological study showed that the increased temperature benefited the integration of the two polymeric phases; however; the temperature of 200°C affected the film quality, generated cracks and holes, which affected the barrier properties of the coatings.

The research involved the synthesis and physicochemical characterization of the polymeric coatings (P3HT, PS/P3HT y PMMA/P3HT), as well as their application as coatings in the steel to prevent corrosion. The effect of thermal treatment of the protective coatings on steel corrosion was studied.

This paper aims to contribute to reducing the problem of metal corrosion through the use of polymer coatings.

Today, majority of metal surfaces are subject under the protection to prevent a very common phenomenon, that is corrosion. Corrosion is the result of chemical reactions that occur between a metal or a metal alloy and its environment. Corrosion creates a degradation of the material that has an impact on some economic, environmental and even social aspects, here the great importance of its protection.

It is shown in this study that the P3HT coating provides better corrosion protection of the A36 steel than the PS and PMMA coatings. However, mixtures of P3HT with PMMA and PS protected the steel from corrosion by two and three orders of magnitude similar to the simple P3HT coating. Polymer blends improved adhesion to the substrate and mechanical property of the coating, and in addition, the polymer blends made cheaper coating.

The objective was to evaluate the effect of banana peel into cake (a bakery product that may add bananas) and panettone (a product that never is added to bananas) formulations on consumers' acceptance and perceived attributes and the effect on the technological properties of the product.

Bakery products were produced with banana peel in the formulation and control samples without residue. Volunteers scored their acceptance and checked all attributes applied to the four samples in the blind and informed tests. The texture, color, proximate composition and bake properties were measured.

The acceptance of both cakes, with and without banana peel, was not affected when consumers were informed that there was a residue in both cakes. Relative risk indicated that information had no influence on acceptance. Panettone with banana pulp showed a reduction in acceptance when volunteers were informed of the presence of banana peel. Risk analysis showed a significant relative risk of product rejection when consumers were aware of information. The addition of banana peel enhanced panettone chewiness and crumb hardness, reduced bake loss of cakes, reduced the volume of both products and changed some color parameters of both products.

Banana peel is a source of functional compounds, but it is not clear how consumers react when informed that the food presents it.

This paper aims to study the corrosion protection of 410 stainless steel (410SS) cracked by fatigue tests. The purpose of this study is to show that using polymeric coatings, it is possible to reduce the corrosion rate in metallic structures in operation.

Poly(3-hexylthiophene) (P3HT)/poly(methyl-methacrylate) (PMMA) composite was used as a coating to protect the cracked 410SS in the corrosive environment 0.5 M NaCl at 25°C and 80°C. Physicochemical characterization was carried out by adhesion tests, thermogravimetric analysis, nuclear magnetic resonance and size exclusion chromatography. Surface morphology was studied before and after the electrochemical tests by scanning electron microscopy. Uncoated and coated cracked 410SS were characterized by DC electrochemical techniques: linear polarization resistance and potentiodynamic polarization curves.

P3HT/PMMA coating reduced corrosion rate and crack propagation of 410SS in the corrosive medium NaCl 0.5M. The P3HT/PMMA coating increased the polarization resistance by one order of magnitude and decreased the corrosion current density by one order of magnitude, relative to the values obtained with uncoated cracked 410SS. The coating helped to have a less damaged surface and less crack propagation on the cracked 410SS. The feasibility of increasing the useful life of cracked metal structures in a saline environment was demonstrated through polymeric composite coatings.

In the literature, no works were detected that report the use of organic coatings to protect cracked metals against corrosion. This is the first reported work on the corrosion protection of 410SS in a saline medium using coatings based on P3HT/PMMA.

This paper aims to investigate the viewpoint of undergraduate Management students at a Brazilian public university regarding the notion of corporate social responsibility (CSR). It theoretically articulates the notion of CSR and the formal education perspective to discuss managerial education.

Stude nts in the Management program were surveyed for their opinion on the notion of CSR. Data were collected through triangulation by combining the application of questionnaire and documentary research. There were 241 valid questionnaires, and this is the size of the sample. Data were analyzed by using the SPSS software (version 20), descriptive statistics and non-parametric tests.

Results reveal that, for undergraduate Management students, the most important CSR dimensions are, in hierarchical order, the philanthropic, the ethical, the legal and the economic. Thus, one can notice an inversion of the original CSR pyramid proposed by Carroll (1991).

The main limitation is the conduction of research in the context of a single public university.

Results indicate a change in how CSR is understood, the philanthropic dimension becoming the main factor for the establishment of organizational goals.

Considering that undergraduate Management students are the future members of the corporate world and decision-makers in society, these results indicate the stance these future professionals will take when confronted by dilemmas involving CSR.

This investigation is original in Brazilian context, for it identifies students’ opinion on CSR using a questionnaire whose development was based on the CSR pyramid.

The recent increase in the number of infections and mortality rates in many regions has emphasized the cyclical nature of this pandemic, with new variants emerging constantly. Understanding what has been done by efficient administrations to contain the outbreak is essential while new immunization developments for the new variants are not available.

This work adapts the traditional Banker, Charnes and Cooper (BCC) Variable Returns to Scale model for including panel data on the Brazilian Federal Government spending over the first pandemic months in Pernambuco to identify efficient municipalities and conduct a benchmark on the best practices, reactions and implications that can serve as a guide for the post-Covid recurrence era.

The results provide an interesting panorama of municipal response to the pandemic and some quantitative and qualitative prospects on potentials for improvements from the perspective of efficient and inefficient cities. Only one administration (São Bento do Una) was identified as efficient for the entire period. The authors’ benchmark and discussion are focused on this municipality.

The authors believe this work has two innovative components. The first is a robust and systematic methodology integrating the advances in testing convexity and returns to scale in the construction of a production frontier based on panel data. The second is a discussion on what drives efficiency (benchmarking of best practices) in addition to how to quantitatively attain such efficiency prospects. To the best of the authors’ knowledge, both methodological and empirical implications are original to the present manuscript.

This chapter identifies research advances in theory and analytics that contribute successfully to the primary need to be filled to achieve scientific legitimacy: configurations that include accurate explanation, description, and prediction – prediction here refers to predicting future outcomes and outcomes of cases in samples separate from the samples of cases used to construct models. The MAJOR PARADOX: can the researcher construct models that achieve accurate prediction of outcomes for individual cases that also are generalizable across all the cases in the sample? This chapter presents a way forward for solving the major paradox. The solution here includes philosophical, theoretical, and operational shifts away from variable-based modeling and null hypothesis statistical testing (NHST) to case-based modeling and somewhat precise outcome testing (SPOT). These shifts are now occurring in the scholarly business-to-business literature.

Importance sampling is a popular Monte Carlo method used in a variety of areas in econometrics. When the variance of the importance sampling estimator is infinite, the central limit theorem does not apply and estimates tend to be erratic even when the simulation size is large. The authors consider asymptotic trimming in such a setting. Specifically, the authors propose a bias-corrected tail-trimmed estimator such that it is consistent and has finite variance. The authors show that the proposed estimator is asymptotically normal, and has good finite-sample properties in a Monte Carlo study.