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Gilles S.,Laboratoire Mixte International Evolution Et Domestication Of Lichtyofaune Amazonienne | Gilles S.,Montpellier University | Gilles S.,Institute Investigaciones Of La Amazonia Peruana Iiap | Ismino R.,Laboratoire Mixte International Evolution Et Domestication Of Lichtyofaune Amazonienne | And 13 more authors.

A prototype of an integrated closed system for fish-plankton aquaculture was developed in Iquitos (Peruvian Amazonia) in order to cultivate the Tiger Catfish, Pseudoplatystoma punctifer (Castelnau, 1855). This freshwater recirculating system consisted of two linked sewage tanks with an intensive rearing unit (a cage) for P. punctifer placed in the first, and with a fish-plankton trophic chain replacing the filters commonly used in clear water closed systems. Detritivorous and zooplanktivorous fishes (Loricariidae and Cichlidae), maintained without external feeding in the sewage volume, mineralized organic matter and permitted the stabilization of the phytoplankton biomass. Water exchange and organic waste discharge were not necessary. In this paper we describe the processes undertaken to equilibrate this ecosystem: first the elimination of an un-adapted spiny alga, Golenkinia sp., whose proliferation was favored by the presence of a small rotifer, Trichocerca sp., and second the control of this rotifer proliferation via the introduction of two cichlid species, Acaronia nassa Heckel, 1840 and Satanoperca jurupari Heckel, 1840, in the sewage part. This favored some development of the green algae Nannochloris sp. and Chlorella sp. At that time we took the opportunity to begin a 3-month rearing test of P. punctifer. The mean specific growth rate and feed conversion ratio (FCR) of P. punctifer were 1.43 and 1.27, respectively, and the global FCR, including fish in the sewage part, was 1.08. This system has proven to be suitable for growing P. punctifer juveniles out to adult, and provides several practical advantages compared with traditional recirculating clear water systems, which use a combination of mechanical and biological filters and require periodic waste removal, leading to water and organic matter losses. © The Animal Consortium 2014. Source

Schreiner K.,European Academy Bozen Bolzano EURAC | Pecher C.,European Academy Bozen Bolzano EURAC | Schermer M.,Universitatsstrasse 15 | Siegl G.,University of Innsbruck | And 3 more authors.
Ekologia Bratislava

An intact landscape has not only an esthetic value, but it also increases the quality of life for the resident population and attractiveness for tourists. The landscape also provides essential ecological services for society, such as soil conservation, preservation of biodiversity, and provision of clean water. The typical cultural landscape in Tyroland South Tyrol was developed in the 15 th century. Cultural-landscape differences arose from different legal traditions between East and West and from a changed legal situation after the affiliation of South Tyrol to Italy.Moreover,the opening of the markets during the 19 th century had the following consequences: Favourable locations were increasingly intensified while peripheral locations became less important and were partly abandoned. Since succession processes proceed slowly in the landscape, the extent of the consequences of land-use changes,such as forest re-growth, are only observable aftermany decades. This study presents an integrative methodical approach that allows comparisons between diverse geographical regions. The applied indicators enable an accurate monitoring of all major features of landscape change including changes in land use, landscape structuring, habitat settings, and urban sprawl. They further provide high-quality and realistic results for our study areas of Tyrol and South Tyrol. Source

Herstad S.J.,University of Agder | Herstad S.J.,Innovation Norway | Sandven T.,Innovation Norway | Ebersberger B.,Universitatsstrasse 15 | Ebersberger B.,TU Berlin
Research Policy

This paper investigates how the strength and intrinsic characteristics of firms' knowledge bases and processing routines have evolved with the past inflow of employees. The empirical analysis is based on linked public register and innovation survey data for Norway. It finds that recruitment from universities, research institutes and higher education institutions has increased the capacity of firms to generate technical inventions. Yet, the organizational knowledge bases and processing routines on which commercial innovation output depends have been strengthened only by the recruitment that has occurred from related industries. Implications for research, management and policy are drawn. © 2014 Elsevier B.V. All rights reserved. Source

Neuner L.,Universitatsstrasse 15 | Lee G.,San Diego State University
Proceedings of the 30th International Conference on Computers and Their Applications, CATA 2015

There exist many applications where one or more robots must perform complex tasks in an uncertain environment. For example, autonomous intelligent robot colonies may be used in reconnaissance missions or seekand- capture scenarios involving a complex set of interactions between machines as well as between machines and humans and may cover long distances to remote sites. Because of the nature of the tasks, new classes of robotic systems will be required that have a high level of specification for efficiency and reliability. In the project presented in this paper, a mobile robotic platform has been designed and built with two sensor modules - an ultrasonic array, along with supporting software using a certainty grid structure that can be used for range finding and obstacle avoidance and an acoustic and infrared sensor system for detecting a target. These sensor modules may be employed in several types of tasks requiring robot platforms to search through unknown environments while finding a desired target. Further, the Virtual Force Field Method for obstacle avoidance has been modified for enhanced performance. The results of this project provides an architecture that may be used in future research and real-world applications involving path planning and path tracking tasks. Copyright © 2015 by The International Society for Computers and Their Applications (ISCA). Source

Kim Y.,Universitatsstrasse 15 | Harders M.,University of Innsbruck | Gassert R.,ETH Zurich
IEEE Transactions on Haptics

Delivering distance information of nearby obstacles from sensors embedded in a white cane - in addition to the intrinsic mechanical feedback from the cane - can aid the visually impaired in ambulating independently. Haptics is a common modality for conveying such information to cane users, typically in the form of vibrotactile signals. In this context, we investigated the effect of tactile rendering methods, tactile feedback configurations and directions of tactile flow on the identification of obstacle distance. Three tactile rendering methods with temporal variation only, spatio-temporal variation and spatial/temporal/intensity variation were investigated for two vibration feedback configurations. Results showed a significant interaction between tactile rendering method and feedback configuration. Spatio-temporal variation generally resulted in high correct identification rates for both feedback configurations. In the case of the four-finger vibration, tactile rendering with spatial/temporal/intensity variation also resulted in high distance identification rate. Further, participants expressed their preference for the four-finger vibration over the single-finger vibration in a survey. Both preferred rendering methods with spatio-temporal variation and spatial/temporal/intensity variation for the four-finger vibration could convey obstacle distance information with low workload. Overall, the presented findings provide valuable insights and guidance for the design of haptic displays for electronic travel aids for the visually impaired. © 2008-2011 IEEE. Source

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