This paper presents a hybrid dynamic model of a 3-D aerial insect-like robot. The soft-bodied insect wings modeling is based on a continuous version of the Newton-Euler dynamics where the leading ...edge is treated as a continuous Cosserat beam. These wings are connected to an insect's rigid thorax using a discrete recursive algorithm based on the Newton-Euler equations. Here we detail the inverse dynamic model algorithm. This version of the dynamic model solves the following two problems involved in any locomotion task: 1°) it enables the net motion of a reference body to be computed from the known data of internal motions (strain fields); 2°) it gives the internal torques required to impose these internal (strain fields) motions. The essential fluid effects have been taken into account using a simplified analytical hovering flight aerodynamic model. To facilitate the analysis of numerical results, a visualization tool is developed (see video available at 1).
Detector Technologies for CLIC Abusleme Hoffman, A C; Parès, G; Fritzsch, T ...
arXiv (Cornell University),
05/2019
Paper, Journal Article
Odprti dostop
The Compact Linear Collider (CLIC) is a high-energy high-luminosity linear electron-positron collider under development. It is foreseen to be built and operated in three stages, at centre-of-mass ...energies of 380 GeV, 1.5 TeV and 3 TeV, respectively. It offers a rich physics program including direct searches as well as the probing of new physics through a broad set of precision measurements of Standard Model processes, particularly in the Higgs-boson and top-quark sectors. The precision required for such measurements and the specific conditions imposed by the beam dimensions and time structure put strict requirements on the detector design and technology. This includes low-mass vertexing and tracking systems with small cells, highly granular imaging calorimeters, as well as a precise hit-time resolution and power-pulsed operation for all subsystems. A conceptual design for the CLIC detector system was published in 2012. Since then, ambitious R&D programmes for silicon vertex and tracking detectors, as well as for calorimeters have been pursued within the CLICdp, CALICE and FCAL collaborations, addressing the challenging detector requirements with innovative technologies. This report introduces the experimental environment and detector requirements at CLIC and reviews the current status and future plans for detector technology R&D.
Synthesis of both enantiomers of the Aspidiotus nerii sex pheromone and their diastereomers has been achieved using, as a key step, an intramolecular ester enolate alkylation reaction for the ...formation of the cyclobutane ring with a good control of the relative configurations of the asymmetric centers. Stereoselective synthesis of a number of other trisubstituted cyclobutane derivatives also proves the versatility of the methodology used for the synthesis of the Aspidiotus nerii sex pheromone.
Several 2,5-disubstituted furans, which are known to react with peroxyacids, singlet oxygen and other active forms of oxygen were tested as potential inhibitors, co-oxidants, or substrates for ...soybean lipoxygenase. The furan, 10,13-epoxy-octadeca-10,12-dienoic acid, methyl ester (IV) was converted by lipoxygenase or singlet oxygen or peroxyacid to the acyclic product, methyl 10,13-dioxo-octadec-11-enoate. Apparently furan IV is able to interact with an active site of lipoxygenase (Km = 220 microM). 2,5-Dimethylfuran (I), 2,5-diphenylfuran (II) and 3-(5'-methyl-2'-furyl)propenoic acid (III) were neither substrates nor inhibitors of lipoxygenase activity. Lipoxygenase-catalyzed oxidation of furan (IV), which is inhibited by hydroquinone, is explained by a mechanism involving lipoxygenase-superoxide complex and furan-radical intermediates. Also described is the selective cleavage of furan rings by m-chloroperoxybenzoic acid to yield the 1,4-diketoethylene functional system.
Thanks to an electro-sensible skin, some species of fish can feel the perturbations of a self generated electric field caused by their surroundings variations. Known under the name of ..."electric-sense", this ability allows these fish to communicate and navigate in confined surroundings wetted by turbid waters where vision and sonar cannot work. Based on a bio-inspired electric sensor recently proposed in 1, this article presents a first attempt to use electric sense for the navigation in formation of a set of rigid underwater vehicles. The navigation strategy combines some behaviours observed in electric fish as well as a follower-leader strategy well known from multi-robot navigation. Being based one the servoing of the electric measurements, these laws do not require the knowledge of the location of the agents. Sufficient convergence conditions of the resulting control laws are given. Moreover, some limits on the possible motion of the leader are exhibited and the importance of the choice of controlled outputs is discussed too. Finally, simulation results illustrate the feasibility of the approach.
The reuse of existing software components for the engineering of complex distributed applications is today a key issue in industrial development projects. Encapsulation and interconnection of ...heterogeneous legacy components have actually been raised as very fundamental issues and partial solutions have been proposed to overcome them such as the use of Object Request Brokers (ORB). However, these approaches do not address some of the issues raised by the construction of a complex distributed application from heterogeneous legacy components. This paper presents a set of configuration tools which intend to assist the application designer in the various stages of the application development life-cycle. This work has been carried out within the Olan project whose main result is an Architecture Definition Language for distributed application engineering and its runtime environment.
PDF
