A Potential Role for Bat Tail Membranes in Flight Control

Wind tunnel tests conducted on a model based on the long-eared bat Plecotus auritus indicated that the positioning of the tail membrane (uropatagium) can significantly influence flight control. Adjusting tail position by increasing the angle of the legs ventrally relative to the body has a two-fold effect; increasing leg-induced wing camber (i.e., locally increased camber of the inner wing surface) and increasing the angle of attack of the tail membrane. We also used our model to examine the effects of flying with and without a tail membrane. For the bat model with a tail membrane increasing leg angle increased the lift, drag and pitching moment (nose-down) produced. However, removing the tail membrane significantly reduced the change in pitching moment with increasing leg angle, but it had no significant effect on the level of lift produced. The drag on the model also significantly increased with the removal of the tail membrane. The tail membrane, therefore, is potentially important for controlling the level of pitching moment produced by bats and an aid to flight control, specifically improving agility and manoeuvrability. Although the tail of bats is different from that of birds, in that it is only divided from the wings by the legs, it nonetheless, may, in addition to its prey capturing function, fulfil a similar role in aiding flight control

A Potential Role for Bat Tail Membranes in Flight Control

Wind tunnel tests conducted on a model based on the long-eared bat Plecotus auritus indicated that the positioning of the tail membrane (uropatagium) can significantly influence flight control. Adjusting tail position by increasing the angle of the legs ventrally relative to the body has a two-fold effect; increasing leg-induced wing camber (i.e., locally increased camber of the inner wing surface) and increasing the angle of attack of the tail membrane. We also used our model to examine the effects of flying with and without a tail membrane. For the bat model with a tail membrane increasing leg angle increased the lift, drag and pitching moment (nose-down) produced. However, removing the tail membrane significantly reduced the change in pitching moment with increasing leg angle, but it had no significant effect on the level of lift produced. The drag on the model also significantly increased with the removal of the tail membrane. The tail membrane, therefore, is potentially important for controlling the level of pitching moment produced by bats and an aid to flight control, specifically improving agility and manoeuvrability. Although the tail of bats is different from that of birds, in that it is only divided from the wings by the legs, it nonetheless, may, in addition to its prey capturing function, fulfil a similar role in aiding flight control

Combining Alternatives in the Multimedia Presentation of Decision Support Information for Real-Time Control

Multimedia technology is emerging as a key element in the area of Decision Support Systems (DSS) since well-designed multimedia presentations help the human decision maker to assimilate relevant information more easily. The use of multiple media, however, increases the complexity of the presentation design task. Especially when complex information structures have to be presented under time pressure `ad hoc ' solutions to presentation generation are getting more and more impractical, if not impossible to use. In this paper we report on our approach to enhance a DSS for real-time traffic management with an advanced component for the automated generation of multimedia presentations. A common problem in this application class is the presentation of alternatives such as different explanations or predictions for a current traffic situation, or different sequences of control actions which may be initiated to resolve a problem. We describe a novel approach to provide aggregated information presentations rather than presenting alternatives just one after the other

An Application-Independent Intelligent User Support System Exploiting Action-Sequence Based User Modelling

Many software systems' usability suffers from their complexity, usually caused by the market-driven trend to bundle a huge amount of features, which are supposed to increase the product's attractiveness. This attempt, however, more often than not leads to software with poor usability characteristics, therefore requiring an extensive amount of initial effort for the users to become familiar with the system. One way to overcome this problem is by providing user-adapted usage support. In thi

Search and Retrieval in Object-Oriented Information Systems

In this paper, we outline the features of a knowledge-based retrieval interface MERIT (Multimedia Extensions of Retrieval Interaction Tools), and VODAK, an object-oriented DBMS suitable for multimedia data. MERIT offers access to a subset of the CORDIS databases with data about European research programs, projects, and consortia in the field of information technology. The system features graphical presentations of retrieval results, employs interactive maps for geographical data, and provides scanned-in documents, e.g. photos of contact persons. The database management system functionality of VODAK is extended such that it treats multimedia data, like text, audio, or video, as an integral part of the databases. Furthermore VODAK is an extendible database management system which allows to integrate information from heterogeneous and distributed resources. Published in: Proceedings of the GI-EMISAWorkshop: "Objektorientierte Methoden für Informationssysteme, Klagenfurt, 7.-9. Juni 1993"..

A Computational Mechanism for Initiative in Answer Generation

Initiative in dialogue can be regarded as the speaker taking the opportunity to contribute more information than was his obligation in a particular discourse turn. This paper describes the use of stimulus conditions as a computational mechanism for taking the initiative to provide unrequested information in responses to Yes-No questions, as part of a system for generating answers to Yes-No questions. Stimulus conditions represent types of discourse contexts in which a speaker is motivated to add unrequested information to his answer. Stimulus conditions may be triggered not only by the discourse context at the time when the question was asked, but also by the anticipated context resulting from providing part of the response. We define a set of stimulus conditions based upon previous linguistic studies and a corpus analysis, and describe how evaluation of these stimulus conditions makes use of information from a User Model. Also, we show how the stimulus conditions are used by the gener..