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Timcenko O.,Copenhagen Institute of Technology | Friesel A.,Copenhagen University
2011 Proceedings of the 22nd EAEEIE Annual Conference, EAEEIE 2011

This paper describes competition-motivated teamwork and narratives to motivate teenager girls, 11-17 years old, to learn programming and basics of control. FIRST LEGO League competitions have been held at the Copenhagen University College of Engineering for several years because of successful cooperation between Ballerup Community, Copenhagen University College of Engineering and Aalborg University in Copenhagen. We focus on girls' engagement in FIRST LEGO League competitions, in order to motivate them in the future to study engineering. LEGO Mindstorm robots and RoboLab graphical programming language were used as technology tools. Using narrative concept and a concept of roles of variables it was possible to explain and provoke children to program by themselves several searching and sorting algorithms, including the algorithms of finding minimal and/or maximal values from the set of input values, as well as make them develop the algorithms for position control by adjusting positional gain. Results are encouraging and could be generalized to other programming languages than RoboLab. © 2011 University of Maribor. Source

Panichnumsin P.,King Mongkuts University of Technology Thonburi | Nopharatana A.,King Mongkuts University of Technology Thonburi | Ahring B.,Copenhagen Institute of Technology | Chaiprasert P.,King Mongkuts University of Technology Thonburi
Biomass and Bioenergy

Cassava pulp is a major by-product produced in a cassava starch factory, containing 50-60% of starch (dry basis). Therefore, in this study we are considering its potential as a raw material substrate for the production of methane. To ensure sufficient amounts of nutrients for the anaerobic digestion process, the potential of co-digestion of cassava pulp (CP) with pig manure (PM) was further examined. The effect of the co-substrate mixture ratio was carried out in a semi-continuously fed stirred tank reactor (CSTR) operated under mesophilic condition (37°C) and at a constant OLR of 3.5kg VS m-3d-1 and a HRT of 15 days. The results showed that co-digestion resulted in higher methane production and reduction of volatile solids (VS) but lower buffering capacity. Compared to the digestion of PM alone, the specific methane yield increased 41% higher when co-digested with CP in concentrations up to 60% of the incoming VS. This was probably due to an increase in available easily degradable carbohydrates as the CP ratio in feedstock increased. The highest methane yield and VS removal of 306mLg-1 VSadded and 61%, respectively, were achieved with good process stability (VFA:Alkalinity ratio<0.1) when CP accounted for 60% of the feedstock VS. A further increase of CP of the feedstock led to a decrease in methane yield and solid reductions. This appeared to be caused by an extremely high C:N ratio of the feedstock resulting in a deficiency of ammonium nitrogen for microbial growth and buffering capacity. © 2010 Elsevier Ltd. Source

Panichnumsin P.,King Mongkuts University of Technology Thonburi | Ahring B.,Copenhagen Institute of Technology | Nopharatana A.,King Mongkuts University of Technology Thonburi | Chaiprasert P.,King Mongkuts University of Technology Thonburi
Water Science and Technology

Microbial community dynamics in response to changes in substrate types (i.e. pig manure (PM), cassava pulp (CP) and mixtures of PM and CP) were investigated in an anaerobic continuously stirred tank reactor (CSTR). Molecular identification of bacterial and archaeal domains were performed, using a 16S rDNA clone library with polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) screening and phylogenetic analysis. Analysis of bacterial clone libraries revealed that the differences in the community structure corresponded to the substrate types. However, the Bacteroidetes were the most abundant group in all substrates, followed by the Clostridia. With pure PM, the dominant bacterial groups were Bacteroidales, Clostridia and Paludibacter. With a co-substrate, at CP to PM (CP:PM) ratio of 50:50, the sequences analysis revealed the greatest diversity of bacterial communities at class level, and the sequences affiliated with Cytophaga sp. became an exclusive predominant. With CP alone, Bacteroides sp. was the dominant species and this reactor had the lowest diversity of bacteria. Archaea observed in the CSTR fed with all substrate types were Methanosaeta sp., Methanosaeta concilii and Methanospirillum hungatei. Among the Archaea, Methanosaeta sp. was the exclusive predominant. The relative distribution of Archaea also changed regarding to the substrate types. © IWA Publishing 2012. Source

Panichnumsin P.,King Mongkuts University of Technology Thonburi | Panichnumsin P.,National Science and Technology Development Agency | Ahring B.K.,Copenhagen Institute of Technology | Nopharatana A.,King Mongkuts University of Technology Thonburi | Chaipresert P.,King Mongkuts University of Technology Thonburi
World Academy of Science, Engineering and Technology

In this study, we illustrated the performance and microbial community of single- and two-phase systems anaerobically co-digesting cassava pulp and pig manure. The results showed that the volatile solid reduction and biogas productivity of two-phase CSTR were 66 ± 4% and 2000 ± 210 ml l -1 d -1, while those of singlephase CSTR were 59 ± 1% and 1670 ± 60 ml l -1 d -1, respectively. Codigestion in two-phase CSTR gave higher 12% solid degradation and 25% methane production than single-phase CSTR. Phylogenetic analysis of 16S rDNA clone library revealed that the Bacteroidetes were the most abundant group, followed by the Clostridia in singlephase CSTR. In hydrolysis/acidification reactor of two-phase system, the bacteria within the phylum Firmicutes, especially Clostridium, Eubacteriaceae and Lactobacillus were the dominant phylogenetic groups. Among the Archaea, Methanosaeta sp. was the exclusive predominant in both digesters while the relative abundance of Methanosaeta sp. and Methanospirillum hungatei differed between the two systems. Source

Ploug T.,Copenhagen Institute of Technology
Studies in Ethics, Law, and Technology

Late 2009, the Microsoft Corporation terminated its sales, distribution and upgrading of Microsoft Office Accounting. This article presents an ethical analysis of the way in which Microsoft Corporation effected its decision to withdraw the product with special emphasis on how consumer expectations were formed, maintained and handled throughout the lifecycle of the accounting software in question. The analysis proceeds from initial reflections on and arguments for the ethical significance of consumer expectations - an area which has until recently only received little attention in moral analysis. © 2010 Berkeley Electronic Press. All rights reserved. Source

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