213 research outputs found

    Typing the untypeable

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    Um seiner NĂ€he zur mĂŒndlichen Kommunikation gerecht zu werden, beinhaltet Internet Chat Diskurs viele Möglichkeiten, um paralinguistisches Verhalten, wie man es aus traditioneller mĂŒndlicher Kommunikation kennt, einzubinden. Da dies ein interessantes Forschungsgebiet darstellt, untersucht diese Arbeit paralinguistisches Verhalten in IRC (Internet Relay Chat) und konzentriert sich dabei insbesondere auf die beiden Gebiete Emoticons und die Möglichkeit, eigene non-verbale Handlungen darzustellen. Grundlage dieser Studie war dabei ein umfangreicher selbst erstellter Korpus von IRC logfiles, der ein reprĂ€sentatives Bild von IRC Kommunikation ermöglichen sollte. Mit Hilfe des Korpus wurden die wichtigsten Emoticons und fĂŒr Selbstzuschreibungen verwendete Verben ausfindig gemacht, sodass GrĂŒnde fĂŒr diese Verteilung diskutiert werden konnten. Eine vergleichende Untersuchung legte nahe, dass sich die Verteilung von Emoticons in den letzten zehn Jahren verĂ€ndert hat. Außerdem ergab eine Untersuchung unterschiedlicher Humor Marker, dass es sich bei diesen um keine echten Synonyme handelt, sondern sich, unter anderem in der IntensitĂ€t, Abweichungen ergeben. Es konnte gezeigt werden, dass die am hĂ€ufigsten verwendeten Selbstzuschreibungen eine Tendenz haben, kommunikative NĂ€he herzustellen und dass ihr Aufgabengebiet, unter anderem, die Verbalisierung von eigenen Gedanken einschließt. Viele der untersuchten paralinguistischen Ausdrucksformen werden sehr hĂ€ufig genutzt und ihre Verwendung scheint fĂŒr Internet Chat Kommunikation von grĂ¶ĂŸter Wichtigkeit zu sein. Mit den Ergebnissen dieser Studie sollte es leichter fallen, zu verstehen, wie und warum diese in IRC eingesetzt werden.Given that internet chat discourse as a ‘new form’ of communication is closely related to oral communication it includes many unique paralinguistic features, which presents an interesting field of research. This thesis examines paralinguistic behaviour in IRC (Internet Relay Chat) and focuses on emoticons and the performance of non-verbal actions. The basis for this research was an extensive corpus of IRC logfiles assembled for this study. The aim was to provide an overview over the most important types of paralinguistic cues in internet chat and to describe how they are employed in IRC. The most frequently used emoticons and verbs for non-verbal actions were identified and reasons for their popularity discussed. A comparative analysis suggested that emoticon use might have changed in the last ten years. Furthermore an investigation of different humour markers revealed that they do not appear to be true synonyms and vary in intensity and range of application. It could be shown that the most frequently transcribed actions tend to represent cues of communicative closeness and that they can also be used to transcribe thoughts. Some features like emoticons and actionmarkers are immensely popular and the use of paralinguistic cues seems to be essential for internet chat communication. With the findings presented in this thesis it should be easier to understand how and why paralinguistic cues are used in the medium of IRC

    Atmospheric Deposition on Swiss Long-Term Forest Ecosystem Research (LWF) Plots

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    Atmospheric deposition of the major elements was estimated from throughfall and bulk deposition measurements on 13 plots of the Swiss Long-Term Forest Ecosystem Research (LWF) between 1995 and 2001. Independent estimates of the wet and dry deposition of nitrogen (N) and sulfur (S) on these same plots were gained from combined simplified models. The highest deposition fluxes were measured at Novaggio (Southern Switzerland), exposed to heavy air pollution originating from the Po Plain, with throughfall fluxes averaging 29 kg ha−1 a−1 for N and 15 kg ha−1 a−1 for S. Low deposition fluxes were measured on the plots above 1800 m, with throughfall fluxes lower than 4.5 kg ha−1 a−1 for N and lower than 3 kg ha−1 a−1 for S. The wet deposition of N and S derived from bulk deposition was close to the modeled wet deposition, but the dry deposition derived from throughfall was significantly lower than the modeled dry deposition for both compounds. However, both the throughfall method and the model yielded total deposition estimates of N which exceeded the critical loads calculated on the basis of long-term mass balance considerations. These estimates were within or above the range of empirical critical loads except above 1800

    Looking for change? Roll the Dice and demand Attention

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    Change detection, i.e. identification per pixel of changes for some classes of interest from a set of bi-temporal co-registered images, is a fundamental task in the field of remote sensing. It remains challenging due to unrelated forms of change that appear at different times in input images. Here, we propose a reliable deep learning framework for the task of semantic change detection in very high-resolution aerial images. Our framework consists of a new loss function, new attention modules, new feature extraction building blocks, and a new backbone architecture that is tailored for the task of semantic change detection. Specifically, we define a new form of set similarity, that is based on an iterative evaluation of a variant of the Dice coefficient. We use this similarity metric to define a new loss function as well as a new spatial and channel convolution Attention layer (the FracTAL). The new attention layer, designed specifically for vision tasks, is memory efficient, thus suitable for use in all levels of deep convolutional networks. Based on these, we introduce two new efficient self-contained feature extraction convolution units. We validate the performance of these feature extraction building blocks on the CIFAR10 reference data and compare the results with standard ResNet modules. Further, we introduce a new encoder/decoder scheme, a network macro-topology, that is tailored for the task of change detection. Our network moves away from any notion of subtraction of feature layers for identifying change. We validate our approach by showing excellent performance and achieving state of the art score (F1 and Intersection over Union-hereafter IoU) on two building change detection datasets, namely, the LEVIRCD (F1: 0.918, IoU: 0.848) and the WHU (F1: 0.938, IoU: 0.882) datasets.Comment: 28 pages, under review in ISPRS P&RS, 1st revision. Figures of low quality due to compression for arxiv. Reduced abstract in arxiv due to character limitation

    A decade of monitoring at Swiss Long-Term Forest Ecosystem Research (LWF) sites: can we observe trends in atmospheric acid deposition and in soil solution acidity?

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    Trends in atmospheric acid deposition and in soil solution acidity from 1995 or later until 2007 were investigated at several forest sites throughout Switzerland to assess the effects of air pollution abatements on deposition and the response of the soil solution chemistry. Deposition of the major elements was estimated from throughfall and bulk deposition measurements at nine sites of the Swiss Long-Term Forest Ecosystem Research network (LWF) since 1995 or later. Soil solution was measured at seven plots at four soil depths since 1998 or later. Trends in the molar ratio of base cations to aluminum (BC/Al) in soil solutions and in concentrations and fluxes of inorganic N (NO3-N + NH4-N), sulfate (SO4-S), and base cations (BC) were used to detect changes in soil solution chemistry. Acid deposition significantly decreased at three out of the nine study sites due to a decrease in total N deposition. Total SO4-S deposition decreased at the nine sites, but due to the relatively low amount of SO4-S load compared to N deposition, it did not contribute to decrease acid deposition significantly. No trend in total BC deposition was detected. In the soil solution, no trend in concentrations and fluxes of BC, SO4-S, and inorganic N were found at most soil depths at five out of the seven sites. This suggests that the soil solution reacted very little to the changes in atmospheric deposition. A stronger reduction in base cations compared to aluminum was detected at two sites, which might indicate that acidification of the soil solution was proceeding faster at these site

    Atmospheric Deposition and Ozone Levels in Swiss Forests: Are Critical Values Exceeded?

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    Air pollution affects forest health through atmospheric deposition of acidic and nitrogen compounds and elevated levels of tropospheric ozone (O3). In 1985, a monitoring network was established across Europe and various research efforts have since been undertaken to define critical values. We measured atmospheric deposition of acidity and nitrogen as well as ambient levels of O3 on 12, 13, and 14 plots, respectively, in the framework of the Swiss Long-Term Forest Ecosystem Research (LWF) in the period from 1995 to 2002. We estimated the critical loads of acidity and of nitrogen, using the steady state mass balance approach, and calculated the critical O3 levels using the AOT40 approach. The deposition of acidity exceeded the critical loads on 2 plots and almost reached them on 4 plots. The median of the measured molar ratio of base nutrient cations to total dissolved aluminium (Bc/Al) in the soil solution was higher than the critical value of 1 for all depths, and also at the plots with an exceedance of the critical load of acidity. For nitrogen, critical loads were exceeded on 8 plots and deposition likely represents a long-term ecological risk on 3 to 10 plots. For O3, exceedance of critical levels was recorded on 12 plots, and led to the development of typical O3-induced visible injury on trees and shrubs, but not for all plots due to (1) the site specific composition of O3 sensitive and tolerant plant species, and (2) the influence of microclimatic site conditions on the stomatal behaviour, i.e., O3 uptak

    Response of carbon fluxes to the 2003 heat wave and drought in three mature forests in Switzerland

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    The effects of the heat and drought of the summer 2003 on carbon (C) fluxes (soil CO2 efflux, dissolved organic carbon in soil, C from litterfall and C sequestration in tree) were investigated in three mature forests in Switzerland between 2001 and 2005. Measurements of the soil matric potential (Κ) indicated a gradient in drought intensity at the three sites (Vordemwald, SchĂ€nis, Beatenberg) with average Κ during the summer 2003 of −75, −41 and −5kPa, respectively. In Vordemwald where the drought was the most severe, the hourly soil CO2 efflux declined by about 30% when Κ<−90kPa. Estimated annual soil CO2 efflux in 2003 was about 10% smaller than effluxes in wetter years (2001, 2002 and 2004) but the differences were not significant. In SchĂ€nis and Beatenberg, no suppression of hourly soil CO2 efflux was observed during the summer 2003. The annual efflux in 2003 at both sites was 10-15% larger than the effluxes in the other years but the differences were not significant. DOC concentrations increased during the first rewetting events after the drought in Vordemwald and in SchĂ€nis. This was mainly due to a concentration effect due to the low soil water content. Because precipitation was lower in 2003, annual DOC fluxes substantially decreased at the three sites. Carbon sequestration in tree stems in Vordemwald declined by 32% in 2003 compared to the mean 2002-2005. In Beatenberg and SchĂ€nis, tree growth responded little to the extreme summer 2003. Litterfall at the three sites showed no marked reaction to the summer 2003. Estimate of annual net ecosystem production (NEP) suggested that the stands in Vordemwald and in SchĂ€nis remained a C sink between 2002 and 2005 but that the extreme summer 2003 caused a decrease in NEP. In Beatenberg, the impact on the NEP seemed to be limited in 2003. The annual NEP in 2003 decreased with increasing drought intensity over the three site

    Enzymfreisetzung und Aktivierung der Kallikrein-Kinin-Systeme bei experimenteller Pankreatitis

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    Das klinische Bild der akuten Pankreatitis wird entscheidend durch die sekundĂ€re SchĂ€digung von Herz-Kreislauf-System, Lunge und Niere bestimmt. Ziel der vorliegenden Untersuchung war es, durch Messungen in venösem Pankreasblut, Pankreaslymphe und Peritonealexsudat die Kompartimente zu bestimmen, ĂŒber die die systemischen SchĂ€digungen vermittelt werden. An anĂ€sthesierten Schweinen wurden die systemischen, hĂ€modynamischen Parameter durch gesteuerte Volumentherapie konstant gehalten. Die Schweine wurden randomisiert der Kontrollgruppe (n = 9) oder einer der Pankreatitisgruppen zugeteilt (jeweils n = 10). Die Pankreatitis wurde durch Infusion von freier FettsĂ€ure in die Pankreasarterien (FFS) oder durch Infusion einer 5%igen Natrium-Taurocholat-Lösung retrograd in den Pankreasgang (NaT) ausgelöst. Nach Isolation des Pankreas wurde venöses Pankreasblut, Pankreaslymphe und Peritonealexsudat gewonnen und die AktivitĂ€t von Lipase, Phospholipase A und Plasmaprokallikrein sowie die Konzentration von Organkallikrein und Kininogen bestimmt. In beiden Pankreatitismodellen fand sich ein Anstieg der EnzymaktivitĂ€ten. Die höchsten AktivitĂ€ten fanden sich im Peritonealexsudat (Phospholipase A nach 40 min: Kontrolle 10,0 U/1, NaT 72,2 U/1). In beiden Pankreatitismodellen fanden sich außerdem Hinweise fĂŒr eine Aktivierung des Organkallikrein-Kinin-Systems durch den Anstieg der Organkallikreinkonzentration und den Abfall der Gesamtkininogenkonzentration. Die stĂ€rksten VerĂ€nderungen fanden sich wieder im Peritonealexsudat (Organkallikrein nach 40 min: Kontrolle 14,7 ng/ml, NaT 452 ng/ml).The clinical course of acute pancreatitis is strongly influenced by secondary cardiac, pulmonary and renal damage. The aim of the present study was to gather information about the compartment promoting the systemic damage. Therefore the activity of lipase, phospholipase A and plasmaprokallikrein and the concentration of tissue kallikrein and kininogen were measured in portal venous blood, pancreatic lymph and peritoneal exudate. Anaesthetized pigs were subjected to fluid resuscitation to keep systemic haemodynamic parameters constant. The pancreas was isolated in situ. The pigs were randomly assigned to a control group (n = 9) or one of the two pancreatitis groups (n = 10 each). Pancreatitis was induced by i.a. infusion of free fatty acid (FFS) or retrograde infusion of 5 % sodium taurocholate intraductally (NaT). In both pancreatitis groups the activity of lipase and phospholipase A increased. The most pronounced changes were seen in the peritoneal exsudate (phospholipase A activity 40 min after induction: control 10.0 U/1, NaT 72.2 U/1). In both pancreatitis groups there was evidence for activation of the tissue kallikreinkinin system in the form of an increase in the kallikrein concentration and a decrease in the kininogen concentration. Again the changes were most pronounced in the peritoneal exsudate (tissue kallikrein 40 min after induction: control 14.7 ng/ml, NaT 452 ng/ml)

    Does exceeding the critical loads for nitrogen alter nitrate leaching, the nutrient status of trees and their crown condition at Swiss Long-term Forest Ecosystem Research (LWF) sites?

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    Nitrogen (N) deposition exceeds the critical loads for this element in most parts of Switzerland apart from the Alps. At 17 sites (8 broadleaved stands, 8 coniferous stands, and 1 mixed stand) of the Swiss Long-term Forest Ecosystem Research network, we are investigating whether N deposition is associated with the N status of the forest ecosystems. N deposition, assessed from throughfall measurements, was related to the following indicators: (1) nitrate leaching below the rooting zone (measured on a subset of 9 sites); (2) the N nutrition of the forest stand based on foliar analyses (16 sites); and (3) crown defoliation, a non specific indicator of tree vitality (all 17 sites). Nitrate leaching ranging from about 2 to 16kgNha−1a−1 was observed at sites subjected to moderate to high total N deposition (>10kgha−1a−1). The C/N ratio of the soil organic layer, or, when it was not present, of the upper 5cm of the mineral soil, together with the pool of organic carbon in the soil, played a critical role, as previous studies have also found. In addition, the humus type may need to be considered as well. For instance, little nitrate leaching (30kgha−1a−1) but characterized by a C/N ratio of 24, large organic C stocks, and a moder humus type. Foliar N concentrations correlated with N deposition in both broadleaved and coniferous stands. In half of the coniferous stands, foliar N concentrations were in the deficiency range. Crown defoliation tended to be negatively correlated with N concentrations in the needles. In the majority of the broadleaved stands, foliar N concentrations were in the optimum nutritional range or, on one beech plot with high total N deposition (>25kgha−1a−1), above the optimum values. There was no correlation between the crown defoliation of broadleaved trees and foliar concentration
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