2,948 research outputs found
Safety Relevant Positioning Applications in Rail Traffic using the European Satellite System "Galileo"
Die Ortung im Eisenbahnverkehr hat eine hohe sicherheitstechnische Relevanz. Eine falsch detektierte Position eines Fahrzeugs kann zu einer erheblichen Gefährdung führen, da die ermittelte Ortsinformation für die Freigabe und das Wiederbesetzen von Gleisabschnitten genutzt wird. Daraus abgeleitet, müssen Ortungssysteme bei der Zulassung unter anderem die folgenden sicherheitskritischen Anforderungen erfüllen Genauigkeit, Zuverlässigkeit, Integrität und Verfügbarkeit der Ortungsinformation, die gemäß SIL 4 nachzuweisen sind
Nonverbal Communication During Human-Robot Object Handover. Improving Predictability of Humanoid Robots by Gaze and Gestures in Close Interaction
Meyer zu Borgsen S. Nonverbal Communication During Human-Robot Object Handover. Improving Predictability of Humanoid Robots by Gaze and Gestures in Close Interaction. Bielefeld: Universität Bielefeld; 2020.This doctoral thesis investigates the influence of nonverbal communication on human-robot object handover. Handing objects to one another is an everyday activity where two individuals cooperatively interact. Such close interactions incorporate a lot of nonverbal communication in order to create alignment in space and time. Understanding and transferring communication cues to robots becomes more and more important as e.g. service robots are expected to closely interact with humans in the near future. Their tasks often include delivering and taking objects. Thus, handover scenarios play an important role in human-robot interaction. A lot of work in this field of research focuses on speed, accuracy, and predictability of the robot’s movement during object handover. Still, robots need to be enabled to closely interact with naive users and not only experts. In this work I present how nonverbal communication can be implemented in robots to facilitate smooth handovers. I conducted a study on people with different levels of experience exchanging objects with a humanoid robot. It became clear that especially users with only little experience in regard to interaction with robots rely heavily on the communication cues they are used to on the basis of former interactions with humans. I added different gestures with the second arm, not directly involved in the transfer, to analyze the influence on synchronization, predictability, and human acceptance. Handing an object has a special movement trajectory itself which has not only the purpose of bringing the object or hand to the position of exchange but also of socially signalizing the intention to exchange an object. Another common type of nonverbal communication is gaze. It allows guessing the focus of attention of an interaction partner and thus helps to predict the next action. In order to evaluate handover interaction performance between human and robot, I applied the developed concepts to the humanoid robot Meka M1. By adding the humanoid robot head named Floka Head to the system, I created the Floka humanoid, to implement gaze strategies that aim to increase predictability and user comfort. This thesis contributes to the field of human-robot object handover by presenting study outcomes and concepts along with an implementation of improved software modules resulting in a fully functional object handing humanoid robot from perception and prediction capabilities to behaviors enhanced and improved by features of nonverbal communication
Lizofoszfolipid mediátorok receptorai. Szfingo- Ă©s glicerolipid növekedĂ©si faktorokat kötĹ‘ fehĂ©rjĂ©k azonosĂtása Ă©s jellemzĂ©se. = Identification and characterization of specific proteins for sphingo- and glycerolipid growth factors
A legegyszerűbb foszfolipidek, a lizofoszfatidsav (LPA) Ă©s a szfingozin-1-foszfát (S1P) jelátvivĹ‘ molekulák, amelyek rĂ©szt vesznek a sejtek tĂşlĂ©lĂ©sĂ©nek, osztĂłdásának Ă©s mozgásainak szabályozásában az egyszerű organizmusoktĂłl az emberig. Kutatásaink cĂ©lja ezen foszfolipidek hatásmechanizmusának megismerĂ©se, a kölcsönhatĂł fehĂ©rjĂ©k azonosĂtása. Az LPA Ă©s az S1P hatását elsĹ‘sorban sejtfelszĂni receptorokon keresztĂĽl fejti ki. Az LPA-receptortĂpusokra szelektĂv aktiválĂł Ă©s gátlĂł molekulák kĂ©t Ăşj csoportját azonosĂtottuk Ă©s jellemeztĂĽk: a zsĂralkohol-foszfátokat Ă©s az oligoprenil-foszfátokat. Sikeresen azonosĂtottuk az S1P1-es tĂpusĂş receptor ligandkötĂ©sĂ©ben rĂ©sztvevĹ‘ apoláros aminosavakat, teljessĂ© tĂ©ve ezzel korábbi munkánkat a kötĹ‘hely feltĂ©rkĂ©pezĂ©sĂ©re. EredmĂ©nyeink a lizofoszfolipid receptorok farmakolĂłgiai vizsgálatának Ăşj lehetĹ‘sĂ©geit teremtik meg. Az S1P kĂĽlönlegessĂ©ge, hogy másodlagos hĂrvivĹ‘ is. EgyĂ©rtelmű bizonyĂtĂ©kot szolgáltattunk arra, hogy az S1P valĂłban intracellulárisan is kĂ©pes a kalcium-ionok felszabadĂtására. LegĂşjabban kimutattuk, hogy az S1P-rokon szfingozilfoszforilkolin köti Ă©s gátolja a kalcium hatását univerzálisan közvetĂtĹ‘ kalmodulint. Az S1P a sejtben keletkezik, tehát sejtfelszĂni receptorai aktiválásához ki kell jutnia onnan. Vizsgáltuk egyes ABC-transzporterek szerepĂ©t ebben a folyamatban. Kimutattuk, hogy az MRP1-fehĂ©rje az S1P egyik lehetsĂ©ges kipumpálĂłja. E fehĂ©rje működĂ©se során fellĂ©pĹ‘ kooperatĂv kölcsönhatásokat is azonosĂtottunk. | The simplest phospholipids, lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) are lipid mediators regulating survival, proliferation, and migration of cells. Our aim is to characterize the mechanisms of action of these phospholipids and to identify their interacting proteins. LPA and S1P exert their actions mainly through cell surface G protein-coupled receptors. We identified two new sets of LPA receptor subtype selective ligands: fatty alcohol phosphates and oligoprenyl phosphates. We also successfully completed the mapping of the ligand binding pocket of the S1P1 receptor, by determining the amino acids lining the hydrophobic part of the binding site. Our results make new pharmacologic interventions possible at lysophospholipid receptors. S1P is unique because it also acts as a second messenger. We provided strict evidence for the action of S1P on the intracellular calcium mobilization from endoplasmic reticulum, independent of cell surface receptors. Very recently we have shown that the related lipid sphingosylphosphorylcholine binds to and inhibits the actions of calmodulin, the ubiquitous calcium sensor of cells. S1P is formed inside cells by the action of sphingosine kinases. It should leave the cell to act as an autocrine/paracrine mediator. We investigated the role of ABC transporters in this process and identified MRP1 as a potential efflux pump for S1P. We also identified cooperative interactions between the ATP and drug binding sites of MRP1
Retrieval Models for Genre Classification
Genre provides a characterization of a document with respect to its form or functional trait. Genre is orthogonal to topic, rendering genre information a powerful filter technology for information seekers in digital libraries. However, an efficient means for genre classification is an open and controversially discussed issue. This paper gives an overview and presents new results related to automatic genre classification of text documents. We present a comprehensive survey which contrasts the genre retrieval models that have been developed for Web and non-Web corpora. With the concept of genre-specific core vocabularies the paper provides an original contribution related to computational aspects and classification performance of genre retrieval models: we show how such vocabularies are acquired automatically and introduce new concentration measures that quantify the vocabulary distribution in a sensible way. Based on these findings we construct lightweight genre retrieval models and evaluate their discriminative power and computational efficiency. The presented concepts go beyond the existing utilization of vocabulary-centered, genre-revealing features and open new possibilities for the construction of genre classifiers that operate in real-time
Legehennefutter mit 100% Ă–ko-Komponenten
EC Regulation 1804/99 requires organic sources of all components of feed in organic husbandry. Especially for organic pig and poultry nutrition it is not researched which components ensure the supply of amino acids.
In our previous studies in 2003 with laying hens with genetics of TETRA, the effect of a high percentage of linoleic acids coming from soybeans was demonstrated. The egg weight increased to an average of 73 g in laying week 38 (ANDERSSON et al. 2004). Consequently we tried in 2004 to reduce the egg weights
• by using the genetics of ISA XH
• by using components with less linoleic acid in the feed.
Using the genetics of ISA XH was one advisable result to reduce egg weights. In this actual study, the hens fed with soybeans laid eggs with highest weight, but on an acceptable level of about 60 – 68 g / egg. Rations with very low energy concentration (9,6 MJ ME, 21 g/kg linoleic acid) were accepted by the hens, while feed consumption increased to more than 145 g/ hen and day. Therefore it seems possible to lower concentrations of amino acids, especially methionine, if the feed intake increases. The laying performance of hens fed with energy concentrations of 9,4 – 9,8 MJ ME was during the laying period of first 14 weeks comparable with the performance of the control group fed with a “standard” ration, later (data only until week 22) it was on a lower but acceptable level
Zur Ausnutzung eines kompensatorischen Wachstumseffektes in der ökologischen Schweinemast
Due to a lack of organic feed with a high quality amino acid pattern it is difficult to achieve the required Lysine-Metabolisable-Energy-ratio in organic grower diets with the danger of reduced value creation. Hence, the present study should investigate whether a moderate oversupply of lysine in the finisher diet after a marginal lysine supply in the grower diet results in compensatory growth. 96 fattening pigs were divided into four groups characterised by different Lysine-ME-ratios in the grower/finisher diets (Experimental Group: 0.69/0.69; Negative Control Group: 0.69/0.59; Positive Control Group: 0.89/0.69; Regular Control Group: 0.89/0.59). Performance and carcass quality were recorded. The economic success was calculated under varying feed cost relevant organic pre-conditions. All groups were similar in performance. The experimental group and the negative control group showed similar but numerically lower lean meat percentages. The negative control group generated the best economic success. It is reasoned that fattening pigs show a certain degree of compensatory growth and that the conventional German lysine recommendations are too high for organic grower diets. Both key findings lead to the conclusion that 100 % organic pig fattening is a resolvable challenge
Ausnutzung eines kompensatorischen Proteinansatzes in der ökologischen Schweinemast
Durch den Mangel an Futtermitteln ökologischer Herkunft mit hochwertigem Aminosäurenmuster besteht die Gefahr zu geringer Lysingehalte in der Anfangsmastration im Vergleich zu den GfE-Bedarfsnormen, woraus eine zu starke Verfettung des Schlachtkörpers resultieren kann. Daher sollte in einer Untersuchung geklärt werden, ob nach einer Lysin-Unterversorgung in der Anfangsmast nach geeigneter Realimentation in der Endmast ein kompensatorischer Proteinansatz stattfindet. Dazu wurden 96 Mastschweine einer modernen Genetik (48 Kastrate, 48 Sauen) in 4 Gruppen mit unterschiedlich gestalteten Lysin-ME-Quotienten in der Anfangs-/Endmastration (Versuchsgruppe: 0,69/0,69; Negativkontrolle: 0,69/0,59; Positivkontrolle: 0,89/0,69; Kontrolle 0,89/0,59) auf Mastleistung, Proteinansatz, Schlachtkörperqualität, Fleischqualität sowie Wirtschaftlichkeit untersucht. Alle 4 Gruppen schnitten bei der Mastleistung (z.B. Lebendmassezunahme, Futterverwertung) und der Fleischqualität (z.B. pH-Werte, LF-Wert) gleich ab. Die N-Bilanz über Futter – Kot – Harn belegte einen kompensatorischen Proteinansatz für die Versuchsgruppe und die Negativkontrolle. Der Muskelfleischanteil (Schlachtkörperqualität) bewegte sich bei der Versuchsgruppe und der Negativkontrolle auf gleichem, aber tendenziell niedrigerem Niveau im Vergleich zur Positivkontrolle und zur Kontrollgruppe. Beim Überschuss des Erlöses über die Ferkel-Futter-Kosten konnte in unterschiedlichen Szenarien gezeigt werden, dass die Negativkontrolle mit steigenden Rationskosten zunehmend besser abschnitt. Das ist der Fall, je stärker durch Restriktionen im ökologischen Landbau der Rationsanteil von Futtermitteln nicht ökologischer Herkunft limitiert wird. Es wird geschlussfolgert, dass nicht auf ein ökonomisch relevantes Kompensationsvermögen beim Mastschwein geschlossen werden kann, und dass unter den spezifischen Fütterungsrestriktionen des ökologischen Landbaus die GfE-Empfehlungen zur Lysinversorgung für die Anfangsmast als zu hoch einzuschätzen sind
- …