Inertial behavior of offshore devices

In the last years, there has been a continued growth in the number of offshore operations for handling large equipment and objects, with emphasis on installation and maintenance of devices for exploiting marine renewable energy like generators for harnessing wind, waves and currents energy. Considering the behaviour of these devices during manoeuvrings, and due to their size and by the interaction with the surrounding fluid, the effect of inertial forces and torques is very important, which requires a specific modelling. This paper especially discusses the masses and moments of inertia modelling problem, with the aim to use it in the simulation of the complex manoeuvres of these devices and in the automatic control systems designed for their offshore operations. Given the importance and complexity of the added mass modelling, a method for its early design identification, developed by the R&D Group on Marine Renewable Energy Technologies of the UPM (GITERM) and its use on special cases like emersion manoeuvres of devices from underwater to the surface will be presented.

Numerical and experimental study of the parametric rolling of a fisihing vessel in regular head waves

The dynamic behaviour of a fishing vessel in waves is studied in order to reveal its parametric rolling characteristics. This paper presents experimental and numerical results in longitudinal regular waves. The experimental results are compared against the results of a time-domain non-linear strip theory model of ship motions in six degrees-of-freedom. These results contribute to the validation of the parametric rolling prediction method, so that it can be used as an assessment tool to evaluate both the susceptibility and severity of occurrence of parametric rolling at the early design stage of these types of vessels.

Field experiences with floating breakwaters in the eastern United States /

In the past 10 years, the use of floating breakwaters as temporary coastal structures has become increasingly widespread in the United States as an inexpensive means for suppressing waves. However, as with any new technology, there have been many failures and a substantial number of imaginative, successful innovations. One of the chief problems contributing to the failure rate has been a lack of awareness by designers of reliable, up-to-date technical information. As part of a large research effort to remedy this problem, a survey was conducted on field experience with floating breakwaters in the Eastern United States. Results of the survey confirmed that state-of-the-art technical literature is not being properly disseminated. Structures built according to early design manuals were shown to have failed before the completion of their design life. Conversely, floating breakwaters built to the standards set by recent research have fared well and show promise of meeting their design golas. The weakest areas of the present technology are flotation and the anchoring systems. It is recommended that a concentrated research effort be directed toward these problem areas; it is also recommended that the monitoring of state-of-the-art projects continue. (Author).

A framework for specification and analysis of software architectures

Software architecture is the abstract design of a software system. It plays a key role as a bridge between requirements and implementation, and is a blueprint for development. The architecture represents a set of early design decisions that are crucial to a system. Mistakes in those decisions are very costly if they remain undetected until the system is implemented and deployed. This is where formal specification and analysis fits in. Formal specification makes sure that an architecture design is represented in a rigorous and unambiguous way. Furthermore, a formally specified model allows the use of different analysis techniques for verifying the correctness of those crucial design decisions. ^ This dissertation presented a framework, called SAM, for formal specification and analysis of software architectures. In terms of specification, formalisms and mechanisms were identified and chosen to specify software architecture based on different analysis needs. Formalisms for specifying properties were also explored, especially in the case of non-functional properties. In terms of analysis, the dissertation explored both the verification of functional properties and the evaluation of non-functional properties of software architecture. For the verification of functional property, methodologies were presented on how to apply existing model checking techniques on a SAM model. For the evaluation of non-functional properties, the dissertation first showed how to incorporate stochastic information into a SAM model, and then explained how to translate the model to existing tools and conducts the analysis using those tools. ^ To alleviate the analysis work, we also provided a tool to automatically translate a SAM model for model checking. All the techniques and methods described in the dissertation were illustrated by examples or case studies, which also served a purpose of advocating the use of formal methods in practice. ^

Integração da simulação termoenergética com o processo de projeto: a análise de 6 casos

This work consists of the integrated design process analyses with thermal energetic simulation during the early design stages, based on six practical cases. It aims to schematize the integration process, identifying the thermal energetic analyses contributions at each design phase and identifying the highest impact parameters on building performance. The simulations were run in the DesignBuilder energy tool, which has the same EnergyPlus engine, validated. This tool was chosen due to the flexible and user friendly graphic interface for modeling and output assessment, including the parametric simulation to compare design alternatives. The six case studies energy tools are three architectural and three retrofit projects, and the author the simulations as a consultant or as a designer. The case studies were selected based on the commitment of the designers in order to achieve performance goals, and their availability to share the process since the early pre-design analyses, allowing schematizing the whole process, and supporting the design decisions with quantifications, including energy targets. The thermoenergetic performance analyses integration is feasible since the early stages, except when only a short time is available to run the simulations. The simulation contributions are more important during the sketch and detail phases. The predesign phase can be assisted by means of reliable bioclimatic guidelines. It was verified that every case study had two dominant design variables on the general performance. These variables differ according the building characteristics and always coincide with the local bioclimatic strategies. The adaptation of alternatives to the design increases as earlier it occurs. The use of simulation is very useful: to prove and convince the architects; to quantify the cost benefits and payback period to the retrofit designer; and to the simulator confirm the desirable result and report the performance to the client

Metodologia para análise da dependabilidade de Smart Grids

Smart Grids are a new trend of electric power distribution, the future of current systems. These networks are continually being introduced in order to improve the reliability of systems, providing alternatives to energy supply and cost savings. Faced with increasing electric power grids complexity, the energy demand and the introduction of alternative sources to energy generation, all components of system require a fully integration in order to achieve high reliability and availability levels (dependability). The systematization of a Smart Grid from the Fault Tree formalism enable the quantitative evaluation of dependability of a specific scenario. In this work, a methodology for dependability evaluation of Smart Grids is proposed. A study of case is described in order to validate the proposal. With the use of this methodology, it is possible to estimate during the early design phase the reliability, availability of Smart Grid beyond to identify the critical points from the failure and repair distributions of components.

Measurability characteristics mapping for large volume metrology instruments selection

Measurement and verification of products and processes during the early design is attracting increasing interest from high value manufacturing industries. Measurement planning is deemed as an effective means to facilitate the integration of the metrology activity into a wider range of production processes. However, the literature reveals that there are very few research efforts in this field, especially regarding large volume metrology. This paper presents a novel approach to accomplish instruments selection, the first stage of measurement planning process, by mapping measurability characteristics between specific measurement assignments and instruments.

Recomendações para o desenvolvimento de uma ferramenta de suporte às primeiras decisões projetuais visando ao desempenho energético de edificações de escritório em clima quente

PEDRINI, Aldomar; SZOKOLAY, Steven. Recomendações para o desenvolvimento de uma ferramenta de suporte às primeiras decisões projetuais visando ao desempenho energético de edificações de escritório em clima quente. Ambiente Construído, Porto Alegre, v. 5, n. 1, p.39-54, jan./mar. 2005. Trimestral. Disponível em: . Acesso em: 04 out. 2010.

Konzeption, Implementierung und Anwendung eines automatisierten aerothermodynamischen Vorentwurfsprozesses für Axialturbinen

In dieser Arbeit wird ein Prozess für den frühen aerothermodynamischen Entwurf von Axialturbinen konzipiert und durch Kopplung einzelner Computerprogramme im DLR Göttingen realisiert. Speziell für die Erstauslegung von Geometrien und die Vorhersage von globalen Leistungsdaten beliebiger Axialturbinen wurde ein neues Programm erzeugt. Dessen effiziente Anwendung wird mit einer zu diesem Zweck konzipierten grafischen Entwurfsumgebung ausgeführt. Kennzeichnend für den Vorentwurfsprozess in dieser Arbeit ist die Anwendung von ein- und zweidimensionaler Strömungssimulation sowie der hohe Grad an Verknüpfung der verwendeten Programme sowohl auf prozesstechnischer wie auch auf datentechnischer Ebene. Dabei soll dem sehr frühen Entwurf eine deutlich stärkere Rolle zukommen als bisher üblich und im Gegenzug die Entwurfszeit mit höher auflösenden Vorentwurfsprogrammen reduziert werden. Die Anwendung der einzelnen Programme im Rahmen von Subprozessen wird anhand von exemplarischen Turbinenkonfigurationen in der Arbeit ebenso dargestellt, wie die Validierung des gesamten Entwurfsprozesses anhand der Auslegung einer folgend realisierten und erfolgreich operierenden Axialturbine eines Triebwerkssimulators für Flugzeug-Windkanalmodelle (TPS). Neben der Erleichterung von manueller Entwurfstätigkeit durch grafische Benutzerinteraktion kommt in einzelnen Subprozessen eine automatisierte Mehrziel-Optimierung zum Einsatz.

A influência de decisões arquitetônicas na eficiência energética do Campus vol. 1/UFRN

Building design is an effective way to achieve HVAC energy consumption reduction. However, this potentiality is often neglected by architects due to the lack of references to support design decisions. This works intends to propose architectural design guidelines for energy efficiency and thermal performance of Campus/UFRN buildings. These guidelines are based on computer simulations results using the software DesignBuilder. The definition of simulation models has begun with envelope variables, partially done after a field study of thirteen buildings at UFRN/Campus. This field study indicated some basic envelope patterns that were applied in simulation models. Occupation variables were identified with temperature and energy consumption monitoring procedures and a verification of illumination and equipment power, both developed at the Campus/UFRN administration building. Three simulation models were proposed according to different design phases and decisions. The first model represents early design decisions, simulating the combination of different types of geometry with three levels of envelope thermal performance. The second model, still as a part of early design phase, analyses thermal changes between circulation halls lateral and central and office rooms, as well as the heat fluxes and monthly temperatures in each circulation hall. The third model analyses the influence of middle-design and detail design decisions on energy consumption and thermal performance. In this model, different solutions of roofs, shading devices, walls and external colors were simulated. The results of all simulation models suggest a high influence of thermal loads due to the incidence of solar radiation on windows and surfaces, which highlights the importance of window shading devices, office room orientation and absorptance of roof and walls surfaces

Recomendações para o desenvolvimento de uma ferramenta de suporte às primeiras decisões projetuais visando ao desempenho energético de edificações de escritório em clima quente

PEDRINI, Aldomar; SZOKOLAY, Steven. Recomendações para o desenvolvimento de uma ferramenta de suporte às primeiras decisões projetuais visando ao desempenho energético de edificações de escritório em clima quente. Ambiente Construído, Porto Alegre, v. 5, n. 1, p.39-54, jan./mar. 2005. Trimestral. Disponível em: . Acesso em: 04 out. 2010.

A influência de decisões arquitetônicas na eficiência energética do Campus vol. 1/UFRN

Building design is an effective way to achieve HVAC energy consumption reduction. However, this potentiality is often neglected by architects due to the lack of references to support design decisions. This works intends to propose architectural design guidelines for energy efficiency and thermal performance of Campus/UFRN buildings. These guidelines are based on computer simulations results using the software DesignBuilder. The definition of simulation models has begun with envelope variables, partially done after a field study of thirteen buildings at UFRN/Campus. This field study indicated some basic envelope patterns that were applied in simulation models. Occupation variables were identified with temperature and energy consumption monitoring procedures and a verification of illumination and equipment power, both developed at the Campus/UFRN administration building. Three simulation models were proposed according to different design phases and decisions. The first model represents early design decisions, simulating the combination of different types of geometry with three levels of envelope thermal performance. The second model, still as a part of early design phase, analyses thermal changes between circulation halls lateral and central and office rooms, as well as the heat fluxes and monthly temperatures in each circulation hall. The third model analyses the influence of middle-design and detail design decisions on energy consumption and thermal performance. In this model, different solutions of roofs, shading devices, walls and external colors were simulated. The results of all simulation models suggest a high influence of thermal loads due to the incidence of solar radiation on windows and surfaces, which highlights the importance of window shading devices, office room orientation and absorptance of roof and walls surfaces

Review on the impact of urban geometry and pedestrian level greening on outdoor thermal comfort

The number of hot days is increasing in many parts of the world because of the heat island phenomenon and global climate change. High air temperature greatly affects human thermal comfort and public health, particularly in urban areas. Therefore, the challenging task of, urban designers and urban planners in accommodating the increasing population is to make cities with the least level of vulnerability to future climate change. Interest in transferring urban climatic knowledge into urban planning practices, and developing mitigation strategies to adapt to climate change, has been increased in recent years. The use of vegetation and appropriate urban geometry are shown very promising in mitigating the adverse effects of heat island and providing a better pedestrian thermal comfort. This article reviews studies on pedestrian level urban greening and geometry in improving thermal comfort in cities. Such strategies can be applied at the preliminary stages of urban planning and thus directly affect the microclimate. The analyzed data include simulation and field measurement studies. The discussion of this research clearly reflects how urban design guidelines can be applied to enhance outdoor thermal comfort and minimize the heat island effect. This study is helpful in controlling the consequences of city design from the early design stage.

User-designer collaboration during the early stage of the design process

As user involvement becomes a necessary part of the product development process, various ways of accessing users' latent needs have been developed and studied. Reviews of literatures in user involvement and product development have revealed that accessing users' latent needs and transferring them into design process could be facilitated by effectively implementing user-designer collaboration during the early stage of the design process. In this paper, various types of user-designer collaboration were observed and then distinct characteristics of user-designer collaboration were classified into three categories. 1) Passive objectivity, 2) workplace democratisation, and 3) shared contexts were observed as strategies for better user-designer collaboration, which have been employed in the area of user-centred design, user participatory design and design for experiencing. Based on the literature review, this paper proposed a basic collaboration mechanism between the users and the designers during the early stage of the design process and then discussed how its mechanism will help to describe the interactions between the users and the designers during the user involvement sessions.