1,720,966 research outputs found
CARE_W : Computer Aided Rehabilitation of Water Networks, EU Fifth Framework Program, (contratto EVK1-CT-2000-00053), 2001-2004
No full textMany cities and districts worldwide approaches a situation with increasing deficit of water needed for urban consumption (households, industry). Expensive projects are planned to bring water supply over long distances or create costly treatment processes. At the same time water losses from distribution network can be up to 50%. Still the reduction of leakage is often not straight-forward, and ageing systems with increasing failure rate increase the stress on the network.
The challenges for urban water distribution have a huge financial dimension. Although they do what they can, many cities and countries do not have the economic capability cope with their problems. They are therefore chasing international funds such as EU structural funds, World Bank etc. This situation is a challenge regarding the fulfilment of the UN Millennium goals for water.
Also in the highest developed countries in financial terms the network ageing is considered as a major challenge into 21 century, and sustainable levels of renovation and corresponding decision criteria is under discussion. Also in these countries the willingness to invest in networks is probably less than the actual need. A minimum ambition should be not to expel the financial burden of water network management to our children and grandchildren generations, and it is the responsibility of researchers to demonstrate consequences of to-days practises.
The contribution of research community can be very important to cope with the problems, by demonstrating the best ways to approach the situation, new technologies and optimization techniques. These approaches can optimise the necessary expenditure of resources to improve the urban water situation for the less favorized regions. This is the background for the extensive joint efforts that has been carried out by 16 research centres and 20 cities Europe-wide and also including Australia, namely the CARE-W project. Intermediate results have been presented in several international conferences, including the IWA World Congresses in Paris, Hamburg, Melbourne and Marrakech. CARE-W is now finished as EU research projects, but it continues with application and implementation world-wide.
The main goals for CARE-W have been to support cities in achieving the right urban water rehabilitation project using the right technology at the right time. The research team had as its vision to support a move from re-active approach to the networks to a pro-active approach. This means leaving the strategy of repairing damages to avoid the damages by preventive rehabilitation, in other words to move from crisis handling to risk based network management. Avoiding damages means saving money. On the other side and there will be a risk of wrong selection of projects and waste of investment capital. To avoid this, better knowledge about the network performance is needed. This can be obtained by a systematic analysis of the relevant factors of network performance based on a systematic collection and processing of urban network information. The information may need to be more extensive than practise in cities, but the main idea is to make the data collection and processing more intelligent.
The network manager of CARE-W acts as the operating system and connect tools to GIS platform and databases. It is also managing the data flow (input and results) between the tools. The tools of the system are summarized as follows:
Objective 1: Status, trends, investments, customer related performance: PI tool on investment and condition for drinking water systems;
Objective 2: Failure forecasting: Tool based on failure history (breaks, leaks) analyzed by stochastic method (Proportional Hazard model);
Objective 3: Hydraulic performance: Hydraulic network and hydraulic reliability model (consequences when pipe stop working);
Objective 4: Socio-economic impact (impact to customer) : Integrated in ranking methodology;
Objective 5:Long-term investment strategies: Based on lif..
CARE_S : Computer Aided Rehabilitation of Sewer Networks - Decision Support Tools for Sustainable Sewer Network Management, EU Fifth Framework Program (contratto EVK1-CT-2001-00167), 2002-2005
No full textThe design and condition of sewer and storm water systems in cities worldwide play a crucial role to protect the inhabitants towards pollution and local floods and mitigate damage on constructions. These silent civil servants are these days focused due to political ambitions on cleaner aquatic environment such as the European “Water Framework Directive”. They are also discussed in relationship to tougher future requirements caused by the expected increase of storm intensity and frequency due to the ongoing climate change. Increased runoff caused by urbanization as well as reduced structural capacity because of ageing is also important driver for a necessary upgrade of the wastewater networks.
Water and wastewater infrastructure are deteriorating with time. Designing these systems for a particular service life and maintaining them in a safe condition during their entire service life have been recognised as very critical issues.
Already to-day many wastewater networks suffer from insufficient capacity, construction failures and pipe deterioration. The consequences are structural damage and local floods leading to inflow of water into basements, traffic disturbances, street and surface erosion, and pollution of local receiving water bodies. European cities spend in the order of 5 billion € per year for wastewater network rehabilitation. This amount is expected to increase significantly over the coming decades.
The rationale behind rehabilitation decisions is unclear. Decisions are often made ad hoc and, in the best case, are based on practical experience after failures appear (reactive approach). Some analytical tools to assess the technical or functional state of sewers or the needs for rehabilitation have been available for some time. Usually, though, they do not take into account all aspects of rehabilitation decisions, and they only have been applied for a limited number of wastewater services.
This is the background for a project in the 5th Framework Programme in EU, Computer Aided Rehabilitation of Sewers and Storm water networks (CARE-S). It is thought that an integrated planning methodology for wastewater upgrading will improve the societal benefit of investments made in the urban wastewater systems. The project objective therefore was to establish a broad rational framework for sewer network rehabilitation decision-making. The system CARE-S aims to improve the structural and functional reliability of the wastewater networks (risk of in- and exfiltration, collapse and blockage due to pipe deterioration, hydraulic overloading resulting in flooding and/or receiving water pollution), identifying optimal preventive maintenance strategies based on lifetime reliability and life-cycle costs. This is combined with the hydraulic analysis of the network capacity to take care of runoff from rainstorms and snow melt in urban areas, even upgrading the system if necessary. The ultimate product is a Decision Support System (DSS) that enables municipal engineers to establish and maintain effective management of their sewer networks. In other words: Rehabilitate the right sewer at the right time by using the right rehabilitation technique at a minimum total cost, before serious failures occur (pro-active approach).
CARE-S supports utilities on planning preventive maintenance which, if it is not done, it will cost more at a later stage to keep the structure in a safe condition
The CARE-S system has already been applied for analysis and planning of wastewater network performance and need for improvement in many cities. It is used to support day operation and progress on information systems that daily work rely upon and to analyse rehabilitation need for specific projects. One main experience is that the urban wastewater networks should be managed according to a three-tier approach: strategic, tactic and technologic level.
The strategic level deals with long term planning, including long term goals and the adoption of best availab..
The hydraulic capacity of deteriorating sewer systems
No full textSewer and wastewater systems suffer from insufficient capacity, construction flaws and pipe deterioration. Consequences are structural failures, local floods, surface erosion and pollution of receiving waters bodies. European cities spend in the order of five billion Euro per year for wastewater network rehabilitation. This amount is estimated to increase due to network ageing. The project CARE-S (Computer Aided RE-habilitation of Sewer Networks) deals with sewer and storm water networks. The final project goal is to develop integrated software, which provides the most cost-efficient system of maintenance, repair and rehabilitation of sewer networks. Decisions on investments in rehabilitation often have to be made with uncertain information about the structural condition and the hydraulic performance of a sewer system. Because of this, decision-making involves considerable risks. This paper presents the results of research focused on the study of hydraulic effects caused by failures due to temporal decline of sewer systems. Hydraulic simulations are usually carried out by running commercial models that apply, as input, default values of parameters that strongly influence results. Using CCTV inspections information as dataset to catalogue principal types of failures affecting pipes, a 3D model was used to evaluate their hydraulic consequences. The translation of failures effects in parameters values producing the same hydraulic conditions caused by failures was carried out through the comparison of laboratory experiences and 3D simulations results. Those parameters could be the input of 1D commercial models instead of the default values commonly inserted
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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