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Nowadays, circular concrete-filled tubular (CFT) columns are largely used in construction because of structural and architectural advantages such as high load bearing capacity and aesthetic appearance. The behavior of CFT columns at ambient and high temperatures is good; however, there are problems related to their behavior in fire when inserted in a real building structure, as for example, the influence of the restraining to thermal elongation that have to be addressed in order to improve their design. This study aims to present the results of a numerical study on the behavior of CFT columns with restrained thermal elongation in case of fire.

The parameters tested in the numerical simulations included column slenderness, load level, surrounding structure stiffness and steel reinforcement ratio. A sequentially coupled thermal stress analysis was carried out. The numerical model was validated with results from a large series of fire resistance tests carried out at Coimbra University, in Portugal. From these, simple equations to evaluate CFT column critical times were derived.

The results were also compared with the ones obtained from the current EN 1994-1-2:2005 simplified calculation and tabulated data methods. For the analyzed cases, it was verified that, while the simplified calculation method led to safe results on the evaluation of the fire resistance of CFT columns with restrained thermal elongation, the tabulated data method led, in certain cases, to unsafe results. This research showed also lower critical times than those from literature on similar type of columns.

The influence of the stiffness of the surrounding structure on the behavior of CFT columns subjected to fire was not yet clear in the major part of the studies already carried out. So, this paper has the originality to consider this parameter in the numerical simulations of this type of columns.

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

The purpose of this paper is to construct a numerical model for the numerical analysis of the hydraulic transient profile in Trabalhador channel for filling and emptying maneuvers and to determine the water level in time. Model results support operational managers in the decision-making process.

Physical data were provided for the construction and calibration of the numerical model. The equations of Saint-Venant were approximated by a finite difference scheme and the numerical model was written in Fortran. The results of filling and emptying of the channel simulations were compared with the measured water levels.

Measured water levels and those simulated by the numerical model have shown good correlation. The time recorded for the filling and emptying of the canal was also close between the measured and simulated data. The simulation design flow pointed to inundation in the channel banks. Simulation water levels were slightly higher than those measured.

In this model, the combination of canals and pressure conduits was not considered.

The findings confirm the measured time for filling and emptying of the canal, as well as inundation of canal banks for the maximum design flow. These results help in the management process.

This paper presents a numerical model for hydraulic transient analysis in channels with good agreement with the field data.

This paper aims to explore the optimization process involved in the aircraft maintenance allocation and packing problem. The aircraft industry misses a part of the optimization potential while developing maintenance plans. This research provides the modeling foundation for the missing part considering the failure behavior of components, costs involved with all maintenance tasks and opportunity costs.

The study models the cost-effectiveness of support against the availability to come up with an optimization problem. The mathematical problem was solved with an exact algorithm. Experiments were performed with real field and synthetically generated data, to validate the correctness of the model and its potential to provide more accurate and better engineered maintenance plans.

The solution procedure provided excellent results by enhancing the overall arrangement of the tasks, resulting in higher availability rates and a substantial decrease in total maintenance costs. In terms of situational awareness, it provides the user with the flexibility to better manage resource constraints while still achieving optimal results.

This is an innovative research providing a state-of-the-art mathematical model and an algorithm for efficiently solving a task allocation and packing problem by incorporating components’ due flight time, failure probability, task relationships, smart allocation of common preparation tasks, operational profile and resource limitations.

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 essence of discounted cash flow valuation is simple; the asset is worth the expected cash flows it will generate, discounted to the reference date for the valuation exercise (normally, the day of the calculation). A survey article was written in Parker (1968), where it was stated that the earliest interest rate tables (use to discount value to the present) dated back to 1340. Works from Boulding (1935) and Keynes (1936) derived the IRR (Internal Rate of Return) for an investment. Samuelson (1937) compared the IRR and NPV (Net Present Value) approaches, arguing that rational investors should maximize NPV and not IRR. The previously mentioned works and the publication of Joel Dean’s reference book (Dean, 1951) on capital budgeting set the basis for the widespread use of the discounted cash flow approach into all business areas, aided by developments in portfolio theory. Nowadays, probably the model with more widespread use is the FCFE/FCFF (Free Cash Flow to Equity and Free Cash Flow to Firm) model. For simplification purposes, we will focus on the FCFE model, which basically is the FCF model’s version for the potential dividends. The focus is to value the business based on its dividends (potential or real), and thus care must be taken in order not to double count cash flows (this matter was treated in this case) and to assess what use is given to that excess cash flow – if it is invested wisely, what returns will come of them, how it is accounted for, etc. (Damodaran, 2006). The bridge to the FCFF model is straightforward; the FCFF includes FCFE and added cash that is owed to debtholders. References: Parker, R.H. (1968). “Discounted Cash Flow in Historical Perspective”, Journal of Accounting Research, v6, pp58-71. Boulding, K.E. (1935). “The Theory of a Single Investment”, Quarterly Journal of Economics, v49, pp479-494. Keynes, J. M. (1936). “The General Theory of Employment”, Macmillan, London. Samuelson, P. (1937). “Some Aspects of the Pure Theory of Capital”, Quarterly Journal of Economics, v51, pp. 469–496. Dean, Joel. (1951). “Capital Budgeting”, Columbia University Press, New York. Damodaran, A. (2006). “Damodaran on Valuation”, Second Edition, John Wiley and Sons, New York.

All information is taken from public sources and with consented company interviews.

Opportunities for value creation may be found in awkward and difficult circumstances. Good strategic thinking and ability to act swiftly are usually crucial to be able to take advantage of such tough environments. Amidst a country-wide economic crisis and general disbelief, José de Mello Group (JMG) saw one of its main assets’ (Brisa Highways) market value tumble down to unforeseen figures and was forced to act on it. Brisa’s main partners were eager in overpowering JMG’s control of the company, and outside pressure from Deutsche Bank was rising, due to the use of Brisa’s shares as collateral. JMG would have to revise its strategy and see if Brisa was worth fighting for; the market implicit assessment about the company’s prospects was very penalizing, but JMG’s predictions on Brisa’s future performance indicated that this could be an investment opportunity. Would it be wise to bet against the market?

This study is excellent for finance and strategy courses, at both undergraduate and graduate levels. Company valuation and corporate strategy are required.

This article aims to present a methodology applied to the transition between the “as-is” and “to-be” stages of the Business Process Management (BPM) life cycle, supporting its implementation and maintenance for the organizational stability, using techniques from Operations Research and Information and Decision Theories, applied by a gamified system.

The study used Design Science Research, considering the following methodological elements: (1) artifact model, after initial analysis of the organization; (2) problem relevance, incorporating components to the Markov transition matrix and the integer programming model for resource optimization; (3) model evaluation, establishing mechanisms to validate the methodology created; (4) research contributions, showing benefits found; (5) systematic approach, detailing methods used; (6) model's research process, revealing the means for execution; and (7) final presentation of results.

After planning three scenarios for the company, containing zero, one or two implemented processes, the matrix of states in the Markov chain effectively identified the states of greater and lesser transition uncertainty. At the same time, the optimization model guided the organization toward a stable change in its operational and financial areas.

The company's planning capacity has increased, as its managers now have a methodology to promote rational decisions about the development of plans. Before, managers believed that the methodology used was only for large companies. However, this view changed with the results, showing a structured view of the ability to absorb new customers, relocate established ones, increase the comfort level for employees and increase profitability for the company's business.

The study showed that the combination of techniques opens a new perspective to the incorporation of BPM in organizations, allows a smooth change between the current and future state, making it possible to predict the evolution of transition scenarios.