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Characterisation of microbial communities for improved management of anaerobic digestion of food waste

Anaerobic digestion of food waste is an attractive and increasingly popular technology within waste management and energy recovery. A better understanding of the microbiology associated with anaerobic digestion of food waste will provide new insight into the operational conditions required for optimizing this process, as well as its potential for utilisation in co-digestion systems. Eighteen full-

Vibration-based structural health monitoring of a wind turbine system Part II : Environmental/operational effects on dynamic properties

The second part of these companion papers mainly researches environmental/operational influences on structural dynamic properties under normal operational conditions during two years, in order to extract a statistical based damage-sensitive indicator for health monitoring of a wind turbine system. The correlation analyses between experimental identified frequencies, damping values as well as mode

Condition monitoring benefit for operation support of offshore wind turbines

As more offshore wind parks are commissioned, the focus will inevitably shift from a planning, construction, and warranty focus to an operation, maintenance, and investment payback focus. In this latter case, both short-term risks associated with wind turbine component assemblies, and long-term risks related to integrity of the support structure, are highly important. This research focuses on the

Resonance phenomenon in a wind turbine system under operational conditions

A prototype of wind turbines in 5 megawatt class was built and tested at the first German offshore wind energy test field in the North Sea. In order to investigate dynamic behaviors under a complex state of loads, a continuous dynamic monitoring system was implemented by Federal Institute for Material Research and Testing (BAM). It recorded structural responses and environmental/operational variab

On the value of structural health monitoring

Health monitoring has, over the last 2-3 decades, become a topic of significant interest within the structural engineering research community, but also in the broader areas of civil and mechanical engineering. Whereas the merits of Structural Health Monitoring (SHM) are generally appreciated in qualitative terms there has, as of yet, not been reported much fundamental research on the quantificatio

Assessing the value of structural health monitoring

Structural Health Monitoring (SHM) systems are designed for assisting owners and operators with information and forecasts concerning the fitness for purpose of structures and building systems. The benefit associated with the implementation of SHM may in some cases be intuitively anticipated or proven by past experiences but in general there appears to be no rational or systematic approach for asse

Effect of different inspection strategies on the reliability of daniels systems subjected to fatigue

Inspections are an efficient means of enhancing the reliability of redundant structural systems subjected to fatigue.To investigate the effect of such inspections, we represent the deterioration state of a Daniels system by means of a probabilistic fatigue crack growth model of all elements, which considers stochastic dependence among element fatigue behavior. We include inspection results in the

Risk and operation optimized damage detection and inspection systems

Damage detection systems are usually developed and optimized based on the methods of damage detection system reliability. This implies that the later purpose of a damage detection system namely e.g. the employment of the structural integrity management is not directly accounted for. This paper addresses thus the issue of optimizing a damage detection system in the perspective its utilization for t

SHM strategies, application and measurements on tripod offshore wind energy converters within the German offshore park Alpha Ventus

Prototypes of wind turbines of the megawatt class are to be built and tested until 2008 within a German offshore wind energy test field in the North Sea (ALPHA VENTUS). To ensure a high operational reliability of offshore wind turbines with economically acceptable repair and maintenance efforts, comprehensive diagnosis and supervision concepts are required. Automatic monitoring systems will be an

Ultimate limit state model basis for assessment of offshore wind energy converters

This paper establishes the model basis regarding the ultimate limit state consisting of structural, loading, and probabilistic models of the support structure of offshore wind energy converters together with a sensitivity study. The model basis is part of a risk based assessment and monitoring framework and will be applied for establishing the "as designed and constructed" reliability as prior inf

Fatigue and serviceability limit state model basis for assessment of offshore wind energy converters

This paper develops the models for the structural performance of the loading and probabilistic characterization for the fatigue and the serviceability limit states for the support structure of offshore wind energy converters. These models and a sensitivity study are part of a risk based assessment and monitoring framework and will be applied for establishing the "as designed and constructed" relia

Probabilistic fatigue crack growth modeling for reliability-based inspection planning

The fatigue deterioration modeling for welded steel structures subjected to high cycle fatigue is presented in the current document. The aim of this paper is to formulate approaches based on actual research results for the phases fatigue crack initiation, fatigue propagation and fatigue failure. The physical characteristics of the approaches are discussed in combination with the associated uncerta

Reliability-based inspection planning with application to orthotropic bridge deck structures subjected to fatigue

A reliability-based approach to inspection planning for welded steel structures subjected to high cycle fatigue is presented in the current document. Inspections are an effective means to control the progress of fatigue deterioration and the presented approach allows to determine the minimum required inspection effort so that the considered structure complies with the given risk acceptance criteri

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This paper contains a summary of the joint research project "OGOWIN: Optimisation of support structures for offshore wind turbines regarding the material consumption, the construction and production sequence as well as new production methodologies". The results comprise (1) a modal analyses of various types of offshore wind turbine support structures, (2) the fatigue strength testing of the cast s

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This paper contains recent research results in the field of monitoring supported structural integrity management. The structural integrity management aims at ensuring the functioning of a structure throughout the life cycle by compliance with the target reliabilities. Building upon research results concerning the characteristics of monitoring techniques and data within the framework of reliability

Results from monitoring and assessment of offshore wind turbines

To ensure a high operational reliability of offshore wind turbines (OWEC) with economically acceptable repair and maintenance efforts, comprehensive diagnosis and supervision concepts are required. Automatic monitoring systems will be an essential part of such concepts. Because of the fact, that during operation there will be static and dynamic interaction between the components 'structure', 'mach

Awesome women and bad feminists: the role of online social networks and peer support for feminist practice in academia

In her book, ‘Bad Feminist’, Roxane Gay claims this label shamelessly, embracing the contradictory aspects of enacting feminist practice while fundamentally being ‘flawed human[s]’. This article tells a story inspired by and enacting Roxane Gay’s approach in academia, written by five cis-gendered women geographers. It is the story of a proactive, everyday feminist initiative to survive as women in

Challenges with strategic placed-based innovation policy: implementation of smart specialization in Estonia and Wales

This paper examines the implementation of smart specialization in Europe and exposes challenges arising from moving towards a more strategic (directional and non-neutral), place-based, and bottom-up mode of regional innovation policy. The analysis focuses on two small European nations – Wales and Estonia – and discusses the challenges that they have experienced with designing and implementing dire

From ‘entrepreneurial’ to ‘engaged’ universities: social innovation for regional development in the Global South

Regional roles of universities in the Global South have been under-explored, and it is not clear how relevant are concepts originating from the Global North when applied in this context. The paper interrogates the concept of the ‘entrepreneurial university’ and its regional impact and engagement via a case study in Brazil. It is found that, in addition to purely entrepreneurial and economic activi