Search results for "VDP::Mathematics and natural science: 400"
showing 10 items of 421 documents
Emigration of mathematicians from outside German-speaking academia 1933-1963, supported by the Society for the Protection of Science and Learning
2012
Author's version of an article published in the journal: Historia Mathematica. Also available from the publisher at: http://dx.doi.org/10.1016/j.hm.2011.08.002 Racial and political persecution of German-speaking scholars from 1933 onward has already been extensively studied. The archives of the Society for the Protection of Science and Learning (SPSL), which are deposited in the Western Manuscripts Collection at the Bodleian Library in Oxford, is a rich source of information about the emigration of European scientists, also those who did not come from German-speaking institutions. This is an account of the support given by the SPSL to the persecuted mathematicians among them. The challenges…
Hans Wußing (1927–2011) and the blooming of the history of mathematics and sciences in the German Democratic Republic – A biographical essay
2012
Authors version of an article published in the journal: Historia Mathematica. Also available from the publisher at: http://dx.doi.org/10.1016/j.hm.2012.01.004
On the thermal instability in a horizontal rectangular porous channel heated from below by a constant flux
2014
Published version of an article in the journal: Journal of Physics: Conference Series. Also available from the publisher at: http://dx.doi.org/10.1088/1742-6596/501/1/012003 Open Access The onset of thermoconvective instability in a rectangular horizontal channel filled with a fluid-saturated porous medium is studied. The channel is heated from below with a constant flux. The top wall is maintained at a uniform constant temperature, while the lateral boundaries are permeable and perfectly conducting. The stability of the basic motionless state is analysed with respect to small-amplitude disturbances. The eigenvalue problem for the neutral stability condition is solved analytically for the n…
Thermal degradation and isomerisation kinetics of triolein studied by infrared spectrometry and GC–MS combined with chemometrics
2008
Authors version of article published in the journal: Chemistry and Physics of Lipids Published version available on Science Direct: http://dx.doi.org/10.1016/j.chemphyslip.2008.12.002 Triolein, a triglyceride containing oleic acid as the only acid moiety in the glyceride molecules has been isothermally treated at 280,300,and 325 degrees C in glass vials under nitrogen atmosphere. The products formed during the thermal treatment at each temperature have been analysed both by infrared spectrometry and GC-MS. The CC-MS analysis was performed after derivatisation of the fatty acids into their methyl esters (FAMEs). Chemometric tools were used in determining the concentrations of the main produc…
Robust H∞ filtering for networked control systems with markovian jumps and packet dropouts
2014
Published version of an article in the journal: Modeling, Identification and Control. Also available from the publisher at: http://dx.doi.org/10.4173/mic.2014.3.3 Open Access This paper deals with the H∞ filtering problem for uncertain networked control systems. In the study, network-induced delays, limited communication capacity due to signal quantization and packet dropout are all taken into consideration. The finite distributed delays with probability of occurrence in a random way is introduced in the network.The packet dropout is described by a Bernoulli process. The system is modeled as Markovian jumps system with partially known transition probabilities. A full-order filter is designe…
Optimized distribution of internationalized DRM-protected multimedia content
2008
Masteroppgave i informasjons- og kommunikasjonsteknologi 2008 – Universitetet i Agder, Grimstad In this project we have looked into different streaming technologies, transport methods and ways of securing the content. We have performed an analysis of the performance in different scenarios, and tested different ways of distributing the content. We have also looked into some of the newest player technologies, and found the reasons for using them, or to look for alternatives. We have found that the best way to deliver content is to use multiple streams and assembling them on the client. This will take more bandwidth, but with todays internet connections this will be acceptable. The solution th…
Identifying Geographic Terms within Natural Language Text
2008
Masteroppgave i informasjons- og kommunikasjonsteknologi 2008 – Universitetet i Agder, Grimstad The huge amount of textual data available in digital form in today’s world increases the need for methods that facilitate ease of access and navigability. Automatic extraction of keywords from text bodies is one promising approach. However, the relevance of keywords are context dependent, and extracting relevant keywords often requires a semantic analysis, simply because words may have different meanings in different contexts. It is well-known that resolving such word sense ambiguity automatically can be very challenging. When the topic of interest is geographic information, important keywords wo…
WLAN 802.11 b/g interference into ZigBee networks
2008
Masteroppgave i informasjons- og kommunikasjonsteknologi 2008 – Universitetet i Agder, Grimstad ZigBee network as a low rate wireless personal area network (LR-WPANs) developed very fast nowadays. Since both ZigBee network and WLAN (802.11b/g) operate in the 2.4GHz unlicensed industrial scientific medical (ISM) frequency band, signal interference is possible to exist and result in signal degradation when devices are collocated in the same environment. This thesis analyzes, simulates and measures the interference and evaluates ZigBee network performance under the WLAN interference in terms of Packet Error Rate (PER) and Packet Loss Ratio (PLR). And the investigation emphasis of this thesis i…
Accurate Measurement and Visualization of Traffic Load in IEEE 802.11 WLANs
2008
Masteroppgave i informasjons- og kommunikasjonsteknologi 2008 – Universitetet i Agder, Grimstad Wireless Local Area Networks (WLANs) based on the IEEE 802.11 standard are getting very popular these days, due to their support for new multimedia services and VoIP, and because WLANs are appearing on more and more small devices. This causes a steadily increasing load and becomes a challenge to network administrators who want to make their WLANs run efficiently and to keep the users satisfied. This Master thesis addresses the lack of efficient and affordable monitoring tools for those running WLANs, by developing an accurate method and for the visualization of traffic patterns and bandwidth util…
Modelling of the Universe : Simulation of the GPS (The Global Positioning System)
2007
Masteroppgave i informasjons- og kommunikasjonsteknologi 2007 – Høgskolen i Agder, Grimstad ParAbel is a project at Agder University College aims at mathematics and physics on Internet. One of the sub projects named SimReal [2] (Simulation in ‘Realfag’), which currently aims at simulating behaviours and properties of universe for both mathematics and physics studying. This project focuses on simulation of the GPS which is one sub task in SimReal. In this paper, on the one hand, we will set up a GPS simulation model and use it to be a teaching material for learning mathematics and physics. On the other hand, by testing the simulation model among the college students, we will discuss about th…