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Clausthal-Zellerfeld, Germany

Birkenfeld S.,CUTEC Institute
2010 World Automation Congress, WAC 2010 | Year: 2010

In order to locate cylindrical objects like pipes and cables buried underground using ground penetrating radar it is necessary to detect reflexion hyperbolas in the measured radargrams. In practice, this task is in many cases complicated due to different geological environments, incomplete or disturbed hyperbolas, and first of all the fact that nearby objects lead to hyperbolas interfering with each other. In this paper we present an automatic detection system based on a specially connected neural network using receptive fields. We show that with an adequate definition of training data the system is capable of reliably detecting reflexion hyperbolas even in those challenging situations. © 2010 TSI Press. Source

Muller E.,Empa - Swiss Federal Laboratories for Materials Science and Technology | Hilty L.M.,Empa - Swiss Federal Laboratories for Materials Science and Technology | Hilty L.M.,University of Zurich | Hilty L.M.,KTH Royal Institute of Technology | And 3 more authors.
Environmental Science and Technology | Year: 2014

Dynamic material flow analysis (MFA) is a frequently used method to assess past, present, and future stocks and flows of metals in the anthroposphere. Over the past fifteen years, dynamic MFA has contributed to increased knowledge about the quantities, qualities, and locations of metal-containing goods. This article presents a literature review of the methodologies applied in 60 dynamic MFAs of metals. The review is based on a standardized model description format, the ODD (overview, design concepts, details) protocol. We focus on giving a comprehensive overview of modeling approaches and structure them according to essential aspects, such as their treatment of material dissipation, spatial dimension of flows, or data uncertainty. The reviewed literature features similar basic modeling principles but very diverse extrapolation methods. Basic principles include the calculation of outflows of the in-use stock based on inflow or stock data and a lifetime distribution function. For extrapolating stocks and flows, authors apply constant, linear, exponential, and logistic models or approaches based on socioeconomic variables, such as regression models or the intensity-of-use hypothesis. The consideration and treatment of further aspects, such as dissipation, spatial distribution, and data uncertainty, vary significantly and highly depends on the objectives of each study. © 2014 American Chemical Society. Source

Birkenfeld S.,CUTEC Institute
World Automation Congress Proceedings | Year: 2014

In many applications of neural networks, e.g. time series prediction or pattern analysis, training data are generated automatically out of large data sets. The problem is to determine the varying significance of the resulting training vectors concerning the given task in order to make appropriate decisions for the training phase. In this paper we propose a self-organized significance analysis based on a rareness assessment for each vector in the generated training data set. The resulting significance measure can be used to achieve considerably improved classification results for a wide variety of applications by systematically controlling training parameters like learning rate or frequency of presentation for each single vector. © 2014 TSI Press. Source

Muller H.,Geschaftsfuhrer der Fa. RATIOTECH | Vodegel S.,CUTEC Institute
Wasser und Abfall | Year: 2013

The uncertainty about the development of energy prices worries many enterprises. New decentralized technologies for biomass gasification offer solutions in which the most diverse hydrocarbons as feed materials are possible. Source

Al Momani F.,CUTEC Institute | Al Momani F.,Mutah University | Schaefer S.,CUTEC Institute | Sievers M.,CUTEC Institute
Ozone: Science and Engineering | Year: 2010

Chemical treatment processes such as ozonation have mostly been considered as an efficient way for bio-solids minimization. The improvement of sludge dewatering was more a welcoming side effect in these sequential processes. However, some times the loaded ozone dose to the sludge has a negative effect on dewaterability.This work address the most important issue found - the effect of ozone on sludge dewaterability in a single ozonation processes as well as in a sequential ozonation biological processes. It was found that the maximum sludge dewaterability was achieved with an ozone dose of 0.05 gO3/gTSS. This value was found to be less than the required ozone dosage that leads to sludge disintegration. However, it was observed that the sequential ozone and aerobic treatment allows further strong improvement of dewatering efficiencies. © 2010 International Ozone Association. Source

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