Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely…
Abstract
Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.
C. Hillenbrand, D. Schmidt and K. Berns
The non‐destructive inspection of large concrete walls (e.g. dams, bridge pylons) with autonomous systems is still an unsolved problem. One of the main difficulties is to develop…
Abstract
Purpose
The non‐destructive inspection of large concrete walls (e.g. dams, bridge pylons) with autonomous systems is still an unsolved problem. One of the main difficulties is to develop a very flexible platform, which is able to move and inspect horizontal and vertical surfaces safely, and which is fast and cost‐efficient. The purpose of this paper is to present a climbing robot designed with these attributes in mind.
Design/methodology/approach
This paper presents the Climbing RObot with Multiple Sucking Chambers for Inspection, which is designed for inspection of concrete walls. The propulsion system consists of three omnidirectional‐driven wheels for high maneuverability. The adhesion is performed by a vacuum system of seven controllable vacuum chambers and one large reservoir chamber. Pressure sensors and valves are integrated for controlling, which allows fast reaction on changing conditions.
Findings
The comparison of simulated results and a simple prototype indicates that the developed physical model is exact enough to estimate the efficiency of the proposed adhesion mechanism. The propulsion system has been tested extensively and allows high maneuverability on reasonably flat ground.
Originality/value
This paper introduces a climbing robot which will allow higher objectivity and reproducibility of inspections as well as safe working conditions for technicians. With such a machine one can check the building via remote control or semi‐autonomously.
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M. Görner, T. Wimböck and G. Hirzinger
The purpose of this paper is to present and evaluate methods of control and gait generation for the DLR Crawler – a six‐legged walking robot prototype based on the fingers of the…
Abstract
Purpose
The purpose of this paper is to present and evaluate methods of control and gait generation for the DLR Crawler – a six‐legged walking robot prototype based on the fingers of the DLR Hand II.
Design/methodology/approach
Following the institutes philosophy, the DLR Crawler is a highly integrated mechatronic device. As in all DLR robots, joint torque sensing plays an important role to allow actively compliant interaction with the environment. To control the Crawler a joint compliance controller is implemented and two different methods of gait generation are in use. The first method, intended for moderately uneven terrain, employs scalable patterns of fixed coordination combined with a leg extension reflex. For the second method, used in rougher terrain, a set of rules found by biologists in stick insect studies is applied. Based on these rules gaits emerge according to a velocity command. These gaits are combined with several reflexes to a reactive walking algorithm.
Findings
The compliance controller together with the reactive gaits allows the robot to autonomously master uneven terrain and obstacles with height differences within the nominal walking height. Further, the controller reduces internal forces compared to pure joint position control. The sensitive joint torque sensors allow fast collision detection and reactions thereafter.
Originality/value
This paper introduces a six‐legged walking robot test bed with comprehensive force‐torque sensing capability. Joint compliance controllers are implemented and successfully combined with reactive gait algorithms. For the second gait algorithm inspired by Cruse's rules, which were identified for forward walking stick insects, an implementation has been found for the DLR Crawler that gives the robot full omnidirectional mobility.
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Résolutions Sous la présidence du professeur W. Hunziker, Berne (Suisse) l'A.I.E.S.T. a tenu son 9e Congrès, du 14 au 19 septembre 1958, à Saint‐Gall, Bregenz, Lindau et…
Abstract
Résolutions Sous la présidence du professeur W. Hunziker, Berne (Suisse) l'A.I.E.S.T. a tenu son 9e Congrès, du 14 au 19 septembre 1958, à Saint‐Gall, Bregenz, Lindau et Constance. Les travaux, portant sur le thème des nouvelles tendances de la politique du tourisme, furent ordonnés autour des rapports suivants:
Allgemeine Feststellungen. Was heisst Sozialtourismus? Seit einiger Zeit macht ein Schlagwort die Runde, findet hier eindeutige Verfechter, weckt dort Befürchtung, Skepsis und…
Abstract
Allgemeine Feststellungen. Was heisst Sozialtourismus? Seit einiger Zeit macht ein Schlagwort die Runde, findet hier eindeutige Verfechter, weckt dort Befürchtung, Skepsis und Ablehnung. Es heisst Sozialtourismus und wird als eine neue Form des Fremdenverkehrs bezeichnet, die seine bisherige Struktur tiefgehend beeinflusse. Um was handelt es sich?
The flight from reason: essays on intellectual freedom in the academy, the press and the library. By DAVID K. BERNINGHAUSEN. Chicago: A.L.A., 1975. 175p. Paper‐backed, $7·50.
Bruce J. Avolio, Benjamin M. Galvin and David A. Waldman
Serious questions have been raised regarding the necessity to continue focusing our research on what constitutes individual, or what the authors refer to as singular leadership…
Abstract
Serious questions have been raised regarding the necessity to continue focusing our research on what constitutes individual, or what the authors refer to as singular leadership. Although the authors consider these questions to be important to advancing the field of leadership theory, research, and practice, they also suggest that attempts to minimize the relevance of singular leadership may hinder progress in other domains of leadership research. In this chapter, the authors explore how and why singular leaders and their leadership matter, and how they may influence follower, peer, and organizational outcomes. The authors use a paradoxical framework to present a theoretical model and propositions that allow us to clarify the influence of different forms of singular leadership within organizations. In our examination of singular leadership, the authors consider both positive and harmful modes of attributes, cognitions, and behaviors.
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Like most traditional forms of tourism also alpine tourism has lost its strategic success positions due to the ongoing globalisation of the tourism sector. The traditional…
Abstract
Like most traditional forms of tourism also alpine tourism has lost its strategic success positions due to the ongoing globalisation of the tourism sector. The traditional structures in tourism marketing — based on political and institutional boundaries — have to make place to a more market oriented structure. The association of swiss tourism managers decided to follow a destination management approach that will lead to corresponding tourism structures. A proposition for such structeres has been presented last year.