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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Effects of multisensory integration processes on response inhibition in adolescent autism spectrum disorder

Chmielewski, W. X., Wolff, N., Roessner, V., Mückschel, M., Beste, C. 02 June 2020 (has links)
Background. In everyday life it is often required to integrate multisensory input to successfully conduct response inhibition (RI) and thus major executive control processes. Both RI and multisensory processes have been suggested to be altered in autism spectrum disorder (ASD). It is, however, unclear which neurophysiological processes relate to changes in RI in ASD and in how far these processes are affected by possible multisensory integration deficits in ASD. Method. Combining high-density EEG recordings with source localization analyses, we examined a group of adolescent ASD patients (n = 20) and healthy controls (n = 20) using a novel RI task. Results. Compared to controls, RI processes are generally compromised in adolescent ASD. This aggravation of RI processes is modulated by the content of multisensory information. The neurophysiological data suggest that deficits in ASD emerge in attentional selection and resource allocation processes related to occipito-parietal and middle frontal regions. Most importantly, conflict monitoring subprocesses during RI were specifically modulated by content of multisensory information in the superior frontal gyrus. Conclusions. RI processes are overstrained in adolescent ASD, especially when conflicting multisensory information has to be integrated to perform RI. It seems that the content of multisensory input is important to consider in ASD and its effects on cognitive control processes.
52

Emotional openness in overweight and normal-weight adolescents

Walther, Mireille, Hilbert, Anja January 2014 (has links)
Obesity is common in adolescence and associated with medical complications. As maladaptive emotional processing is assumed to influence obesity, this research investigated emotional openness (EO), a general model of emotional processing, in normal-weight versus overweight adolescents, with consideration of gender differences, in order to determine whether a particular EO profile is characteristic of overweight adolescents. This research also explored the psychometric characteristics of the Dimensions of Openness to Emotions Questionnaire (DOE-20), a comprehensive multifactorial instrument that assesses emotional processing. The DOE-20 and the Positive and Negative Affect Schedule (PANAS) short form were completed by 160 adolescents (mean age: 14.36 ± 0.61 years), 39 of which were overweight. A multivariate analysis of variance showed no difference with respect to overweight status, but better ability to recognize and regulate emotions in boys than girls. The original five-factor structure of the DOE-20 was confirmed by confirmatory factor analysis; however, internal consistency was modest. As this research did not replicate the EO profile previously found in obese adults, we discuss the adequacy of the DOE-20 to evaluate EO in adolescents as well as the ability of the construct of EO to assess emotional processing in obesity. Further research should examine the links between EO, problematic eating behaviors, and obesity.
53

Emotional openness, problematic eating behaviours, and overweight in adolescents

Walther, Mireille, Hilbert, Anja January 2015 (has links)
Overweight, a common health condition in adolescence, has been linked with difficulties in emotional processing. This study investigates associations between emotional processing, conceptualised through the model of Emotional Openness (EO), problematic eating behaviours, including Eating in the Absence of Hunger and disinhibited eating, and overweight in adolescents. Several self-report instruments were completed by 160 youngsters (mean age: 14.36 ± 0.61 years) from the community, including 39 overweight and obese adolescents (24.5%). In girls, bootstrap analyses supported a mediating effect of restrained eating on the relation between three EO dimensions and body mass index percentile, in particular the communication of emotions, the cognitive-conceptual representation of emotions, and the perception of bodily indicator of emotions. No mediating effect was found in boys. These results have important implications for psychological weight management interventions, as they underline the relevance of work on emotional processing in order to reduce problematic eating behaviours.
54

Reibmessgerät zur Bestimmung des Gleitreibkoeffizienten von bahnförmigen Packstoffen

Kayatz, Fabian, Claus, Ronald January 2014 (has links)
No description available.
55

Zum Kalkbergbau im Nossen-Wilsdruffer Schiefergebirge - Von Miltitz bis Schmiedewalde -

Boeck, Helmut-Juri 04 March 2017 (has links)
Dokumentationsreihe zum Sächsischen Bergbau, Reihe 1 Kalkbergbau:Eine Vorbemerkung ................................................................................................. Zur Lage und Regionalgeschichte der Triebischtäler .............................................. Zur Geologie des Nossen- Wilsdruffer Zwischengebirges und der Kalklager ....... Überblick ............................................................................................................... Die Kalkvorkommen in den unteren Triebischtälern .............................................. Weitere paläozoische Kalkvorkommen ................................................................. Der Kalktuff von Robschütz .................................................................................. Zu den bergrechtlichen Besonderheiten des Kalkstein- Bergbaus ........................ Zum Abbau der Kalklager ...................................................................................... Zur Verarbeitung des „Marmors“ ........................................................................... Das Kalkbrennen (Technischer Kalk-Kreislauf) ..................................................... Zu den Brennöfen vom „Schneller“-Typ ................................................................ Ablöschen des Branntkalks .................................................................................. Das Abbinden ....................................................................................................... Der natürliche Kalkkreislauf .................................................................................. Zur Produktion und zum Absatz der Kalkwerke..................................................... Zur Produktion der einzelnen Werke .................................................................... Bemerkungen zum Absatz .................................................................................... Zur Geschichte des Abbaus .................................................................................. Das von Heynitz'sche „Alte Kalkwerk“ in Miltitz .................................................... Das K. Jurisch'sche „Neue Kalkwerk“ in Miltitz ..................................................... Das Kalkwerk Groitzsch (Kippe & Pietzsch) ......................................................... Die Ranft'schen und Geißler'schen Kalkwerke bei Schmiedewalde ................... Schmutzler ́s Kalkwerk in Burkhardswalde ......................................................... Bergbauzeugnisse Übertage ............................................................................... Untertage im Alten Kalkbergwerk Miltitz .............................................................. Unterwasser im Alten Kalkbergwerk Miltitz ......................................................... Quellenauswahl ................................................................................................... Impressum ........................
56

Zum Kalkbergbau im Nossen- Wilsdruffer Schiefergebirge - Von Blankenstein bis Grumbach / Braunsdorf -

Boeck, Helmut-Juri 04 March 2017 (has links)
Dokumentationsreihe zum Sächsischen Bergbau, Reihe 1 Kalkbergbau in Sachsen:Zur Lage und Regionalgeschichte des mittleren Triebischtales .............................. Zur Geologie der Kalksteinvorkommen im mittleren Triebischtal ........................... Überblick ............................................................................................................... Zum Dolomit ......................................................................................................... Zur Geschichte des Abbaus .................................................................................. Die Kalkwerke Hahn und Faust (Zschalig) in Blankenstein .................................. Das Kayser'sche (Kluge's) Kalkwerk zu Steinbach ............................................... Kalksteinabbau an der Kirsten- Mühle bei Helbigsdorf ......................................... Kalkwerke Krumbiegel und Wätzig, bei Grumbach bzw. Braunsdorf später Vereinigte Braunsdorfer Dolomitwerke ...................................................... Erhaltene Zeugnisse ............................................................................................. Quellenauswahl ................................................................................................... Impressum ..........................................................................................................
57

Zum Abbau des Plattendolomits am Südostrand der Frohburg-Bornaer Mulde

Boeck, Helmut-Juri 04 March 2017 (has links)
Dokumentationsreihe zum Sächsischen Bergbau. Reihe 1 Kalkbergbau von Sachsen:Zur naturräumlichen Lage und regionalen Geschichte ............................................ Zur Geologie ......................................................................................................... Zur Montangeschichte und zur Entwicklung der Brenntechnik .............................. Zum „Geithainer Brennofen“ ................................................................................. Abbau untertage? ................................................................................................. Zum Hoffmann'schen Ringbrandofen ................................................................... Zur neuzeitlichen Geschichte................................................................................ Erhaltene Zeugnisse ............................................................................................. Quellenangaben .................................................................................................. Impressum .......................
58

Zum Abbau des Plattendolomits am Südostrand der Frohburg-Bornaer Mulde in der Region um Tautenhain und Ebersbach

Boeck, Helmut-Juri 04 March 2017 (has links)
Dokumentationsreihe zum Sächsischen Bergbau. Reihe 1 Kalkbergbau in Sachsen:Zur naturräumlichen Lage und regionalen Geschichte ............................................ Zur Geologie ........................................................................................................... Zur Montangeschichte ............................................................................................. Erhaltene Zeugnisse ............................................................................................. Quellenangaben .................................................................................................... Impressum ........
59

Universal tool LASER - application examples for welding of HT fuel cells as well as heat exchangers and tank systems for H2 processing

Standfuss, Jens, Dittrich, Dirk, Klotzbach, Annett, Mohlau, Phillip, Strohbach, Robert, Leyens, Christoph 25 November 2019 (has links)
The laser tool is predestined for automated manufacturing processes and has already proven its suit-ability in many areas. In particular, joining technologies in the field of hydrogen production, its storage and for bi-polar plates have to meet the highest requirements in terms of seam quality, reproducibility and manufacturing efficiency. By the examples  700 bar car H2 pressure tank with laser welded connection (welding depth 25 mm)  Laser Remote Welding of HT Fuel Cell Stacks  Laser-welded aluminum tube-ground heat exchanger for gas liquefaction the article presents the possibilities of modern laser beam welding technologies. Furthermore, it gives an outlook on future challenges, especially with regard to the requirements of welding bi-polar plates for upcoming applications in the field of mobility
60

Analysis of rate-dependent deformation and fracture phenomena during cutting of viscoelastic materials

Schuldt, Stefan 14 September 2018 (has links)
The cutting of foods is characterized by deformation, fracture and friction processes, and the viscoelastic properties of the cutting materials determine their rate-dependent cutting behavior. This is responsible for uncontrolled fracture and deformation events with increasing cutting velocity. There is a significant information deficit regarding the assignment of material properties and cutting parameters, as well as regarding a process description for industrial high-speed cutting. The aim of the work is the analysis of the velocity-dependent cutting behavior of foods up to the high-speed range. The focus is on the deformation and fracture phenomena, analysed by methods of classical material analysis but also associated cutting experiments performed in the range from low to high cutting velocities. For high-speed analyses, a test station enabling cutting velocities of up to 10 m/s was designed. To identify relevant material and cutting parameters and to establish a systematic experimental program, elastomer-based model systems with controllable viscoelastic profiles were developed. The results of the respective investigations were further verified for foods. The velocity-dependent deformation behavior during cutting could be described by dynamic-mechanical material analyses in the frequency range. Cutting force slopes at the beginning of the cutting process correlated with the complex moduli and were furthermore dependent on the cutting velocity; this dependency corresponded to the frequency behavior from material analysis. The fracture properties could be attributed to ductile (polymeric systems) or brittle behavior (cellular plant systems). Confectionary products had a strong temperature- and time-dependent behavior with ductile-brittle transition within the experimental conditions. The results obtained demonstrate that there is a significant relationship between viscoelasticity and velocity-dependent cutting behavior. They allow a phenomenological process description of high-speed cutting and can be used as a basis for the balancing of cutting forces and as input parameters for numerical analyses of the cutting process. / Das Schneiden von Lebensmitteln ist geprägt durch Deformations-, Bruch- und Reibvorgänge. Dabei bestimmen die viskoelastischen Eigenschaften der Schneidgüter deren geschwindigkeitsabhängiges Schneidverhalten. Dies führt mit zunehmender Schneidgeschwindigkeit zu unkontrollierten Bruch- und Deformationsereignissen. Dabei besteht ein Informationsdefizit bei der konkreten Zuweisung von Materialeigenschaften und Schneidparametern sowie einer Verfahrensbeschreibung für das industrielle Hochgeschwindigkeitsschneiden. Ziel der Arbeit ist die Analyse des geschwindigkeitsabhängigen Schneidverhaltens von Lebensmitteln bis in den Hochgeschwindigkeitsbereich. Der Fokus richtet sich auf die Untersuchung der Teilphänomene Deformation und Bruch durch Methoden der klassischen Materialanalyse sowie zugeordnete Schneidexperimente im Bereich von niedrigen bis hohen Schneidgeschwindigkeiten. Für entsprechende Hochgeschwindigkeitsanalysen wurde ein Versuchsstand mit Schneidgeschwindigkeiten von bis zu 10 m/s konzipiert. Zur Identifikation relevanter Material- und Schneidparameter und zur Aufstellung des systematischen Versuchsprogramms wurden Modellsysteme auf Elastomerbasis mit steuerbarem viskoelastischen Profil entwickelt. Die Ergebnisse wurden für Lebensmittel verifiziert. Das geschwindigkeitsabhängige Deformationsverhalten beim Schneiden konnte durch dynamisch-mechanische Materialanalysen im Frequenzbereich beschrieben werden. Dabei korrelierten Kraftanstiege zu Beginn des Schneidvorganges mit den Komplexmoduln. Die Anstiege zeigten eine Abhängigkeit von der Geschwindigkeit; diese entsprach dem Frequenzverhalten aus der Materialanalyse. Die Brucheigenschaften konnten produktspezifisch duktilem (polymere Systeme) oder sprödem Verhalten (zelluläre, pflanzliche Systeme) zugeordnet werden. Zuckerwaren zeigten ein stark temperatur - und zeitabhängiges Verhalten mit duktil-sprödem Übergang innerhalb der Versuchsbedingungen. Die gewonnenen Erkenntnisse demonstrieren den Zusammenhang von Viskoelastizität und geschwindigkeitsabhängigem Schneidverhalten. Sie erlauben eine phänomen ologische Verfahrensbeschreibung des Hochgeschwindigkeitsschneidens und können als Basis für die Bilanzierung von Schneidkräften und als Eingangsparameter für numerische Analysen des Schneidvorganges dienen.

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