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Impact loadings such as vehicle collisions or falling rocks on a structure could lead it to collapse and, eventually, to fatal victims. Among possible alternatives to analyse this issue, Lumped Damage Mechanics is an interesting option due to its formulation and easiness for practical application. Therefore, this paper presents a simplified Lumped Damage model to evaluate reinforced concrete structures under impact loads with shear failure mode. In the proposed approach, the damage variable is considered as an output parameter. Such damage variable takes values between zero and one, which quantifies the concrete cracking due to impact loading. The proposed formulation was applied in experiments of reinforced concrete beams under impact loads that presents shear collapse. The obtained results showed good accuracy between the proposed model and the actual structural behaviour. Moreover, a possible flowchart for practical applications is also presented. Since the model parameters are easily associated to inelastic phenomena, the proposed formulation might become accessible to engineers in practice.

Analysis of RC structures subjected to seismic loads vary greatly around the world, from simplified static models to more advanced methods, which take account of real dynamic loads and the nonlinear response of structures. As a recent theory, lumped damage mechanics apply the concepts of damage mechanics and the classic fracture in plastic hinges for nonlinear analysis of RC structures. Therefore, this research analysed the behaviour of RC dual system structures designed according to Brazilian Standards Codes, that did not consider the recommendations of NBR 15421, under seven real seismic loads, with magnitude units in Richter scale (ML). It was concluded that all structures regardless of structural system and number of storeys might suffer severe values of structural damage when subjected to earthquake magnitudes equal or greater than 5.0 ML. Besides that, even for earthquake magnitudes above 3.0 ML, in most of structures, the interstorey drift ratio was not in requirements with international standard codes, causing cracking in nonstructural elements and demanding higher repair costs.

With datacenters expanding their networks at a greater than ever rate, efficiently managing an extremely numerous a network of servers with high cabling complexity is a daunting task. This has motivated the rise of free-space optics (FSO) communication technologies, as a reliable new solution for high-capacity communication systems, which grants a possibility for the implementation of cable-free intra-datacenter communications as a way to reduce the level of network complexity. However, as the scientific community continuously explores FSO distinctive characteristics of unregulated large-bandwidth spectrum, to easily establish new communication links, atmospheric conditions threaten its commercial deployment. As such, the effects of atmospheric turbulence on FSO links have been under investigation by researchers from all over the world, leading to the proposal of several models in an attempt to predict and therefore mitigate the effects of adverse conditions. This study seeks to capture and analyze experimental data on the influence of turbulence on the received optical power of a FSO link in a controlled room, to simulate a datacenter environment, followed by the modeling of experimental data using the Log-Normal model. Using a small 2000 RPM Fan in three different positions we increased the atmospheric turbulence of the FSO channel and measured the differences in received optical power over the course of 1 hour per position. These measurements are then compared to a control obtained without externally induced turbulence. Using the obtained data, we demonstrate its Log-Normal fit, thus enabling to determine the Rytov variance for each scenario.

It is assumed in this paper that energy dissipation is a two-phase phenomenon. During the pre-localization stage, dissipation is a continuous process. After localization, it is lumped in surfaces of zero volume. To describe this process, it is proposed a new formulation called extended damage mechanics. The new framework incorporates the additional terms of lumped energy dissipation into a weak form of the damage evolution law. The variational formulation allowing for this approach characterizes the solution as a non-cooperative equilibrium point. This concept is also named after its inventor, the mathematician John Forbes Nash, as Nash point. Finally, numerical implementation of the extended damage mechanics is performed to describe the objectivity of the numerical simulations with respect to the finite element meshes in some practical cases of solids and structures.

The analysis of reinforced concrete structures can be performed by means of experiments or numerical studies. The first way is usually quite expensive, so the second one sometimes is a good option to understand the physical behaviour of actual structures. Lumped damage mechanics appears as one of the latest nonlinear theories and presents itself as an interesting alternative to analyse the mechanical behaviour of reinforced concrete structures. The lumped damage mechanic applies concepts of the classic fracture and damage mechanics in plastic hinges for nonlinear analysis of reinforced concrete structures. Therefore, this paper deals with a novel physical definition of the correction factor γ for cracking evolution that ensures the presented lumped damage model depicts accuracy when it is compared to experimental observations of reinforced concrete beams and arches. Based on such experiments, the numerical analysis showed that γ value has upper and lower thresholds, depending on the physical and geometric properties of the reinforced concrete element. Notwithstanding, for γ values inside of the proposed interval, there is a best value of γ.

Structural design procedures are based on simplified hypotheses that attempt to approximate the actual behaviour. Depending on the adopted hypothesis, the design procedure may not satisfactorily describe the structural actual behaviour. Such condition occurs in the design of reinforced concrete pipes, where there are uncertainties related especially on the internal forces and the installation type of the pipe. Moreover, the main design hypothesis is that the cross section is plane and perpendicular to the deformed axis. Based on materials resistance principles it is known that this hypothesis is unsatisfactory to pipes with aspect ratio lower than ten. Note that the commercial reinforced concrete pipes usually present aspect ratio well below ten. In the light of the foregoing, the main objective of this paper is to analyse the accuracy of the design procedure for reinforced concrete pipes. Therefore, statistical processes were used to compare design values with experimental results. The comparisons in this paper showed that the design procedure results in oversized pipes.

Due to errors made during the production process, the printed version of the article contained one duplicate reference, which led to an inconsistent numbering in the reference list, and one incorrect citation in Table 3. The online version of the article has been updated with the corrections. The authors would like to apologize for any inconvenience caused.

O gerenciamento hídrico compreende não só a captação de dados, mas também o tratamento, armazenamento e posterior apresentação ao usuário. Deste modo, o presente trabalho buscou desenvolver uma aplicação web usando a biblioteca Google Charts para que os dados sejam apresentados de forma gráfica. O trabalho desenvolvido no Laboratório de Hidráulica do Instituto de Ciências Agrárias da Universidade Federal de Minas Gerais, valeu-se da linguagem de programação JavaScript e da biblioteca jQuery para recuperar dados de um reservatório, armazenados em um servidor web e plotá-los em uma página HTML. Deste modo, criou-se uma aplicação que apresenta ao usuário o estado de um reservatório em tempo real, pois, o gráfico de nível do mesmo é atualizado a cada minuto. Concluiu-se então que o uso da biblioteca Google Charts no gerenciamento hídrico é viável, apresentando a gestores de recursos hídricos uma nova ferramenta de apoio a tomada de decisões. Water management comprises not only the capture of data, but also the treatment, storage and subsequent presentationto the user. Thus, the present work sought to develop a Web application using the Google Charts library so that the data will be presented graphically. The work, developed at the Hydraulics Laboratory of the Agricultural Science Institute of the Federal University of Minas Gerais, used the JavaScript programming language and the jQuery library to retrieve data from a reservoir, stored on a Web server, and plot them in an HTML page. In this way, an application is created that presents the user with the state of a reservoir in real time, Therefore, the same level chart is updated every minute. It was then concluded that the use of the Google Charts Library in water management is feasible, introducing water resource managers a new tool to support decision-making.

Objective Hand sensory tests do not consider distinct physiological receptors, nor detect normal range variations concerning developmental or pathological changes. We developed an instrument with a set of tests with timing and scoring for assessing haptic perception, which is the interaction between sensory and motor systems, in surfaces exploration, by moving hands. Method Firstly, group meetings were set for test/manual conception and materials testing. The test/manual were submitted to 30 reviewers in 3 stages (10 reviewers on each stage). Results The Hand Haptic Perception Instrument (HHPI) evaluates hand sensorimotor performance on six domains: depression, elevation, texture, compressibility, weight (barognosis) and form perception. Each domain requires specific materials. Score ranges from 0 to 57, being 0 the worst rating. Conclusion This methodological process allowed the development of six domains and instructions to assess haptic perception. This version of HHPI is a pilot model. Further studies will determine reliability and normality ranges.

This paper presents a simple lumped damage model to analyse reinforced concrete beams under impact loads. The proposed model is based on the thermodynamics of irreversible processes. In this framework, key concepts of fracture and damage mechanics are applied on plastic hinges. Since the inelastic phenomena are modelled by two internal variables, named damage and plastic rotation, the plastic hinges are now called inelastic hinges. Therefore, the proposed finite element is an assemblage of an elastic beam with two inelastic hinges at its edges. Experimental results are used to propose the evolution laws of the internal variables. The proposed model is applied to other experiments and the obtained results show its accuracy. Finally, if an extensive experimental campaign could be carried out, a practical engineering criterion can be elaborated in terms of the damage variable (concrete cracking), which may be useful as a decision-making criteria for retrofit worthiness.

When managing software development projects, it is common to have some problems during the iterations of the project. This work presents an analysis and review of agile methodologies and some of the most well-known project management techniques, all these methodologies and techniques contextualized in the computational scope. Based on this information was possible to propose a new model more comprehensive that allows the mitigation of some recurring problems in the progress of software projects and give to final users good results. It was detailed a case study of an innovative project entitled “Calculadora CUG”, where the combination of referenced techniques and concepts were introduced in the development process allowing more flow to some of the features of the project pointed out by the client (first final user) and to create, in a way, more efficient releases in involvement with the user.

Due to the Crisis of 2008, the Basel Committee accelerated the process for update the Accord and identified some weaknesses such as the inability of VaR to capture the tail risk. Subsequently, it was recommended to substitute VaR, a non-coherent measure of risk due to the absence of subadditivity, by CVaR. This measure, while not being testable or elicitable, is at least conditionally elicitable and therefore also conditionally testable. To validate the CVaR models, simulations were made with the three Acerbi methods and another one suggested in this paper that adapted the Quantil Approximation. Of these four, none was perfect. The three Acerbi methodos had failures in some tests and the one suggested in this paper presented better results than the VaR Backtesting.