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31.
The complexity of a standard compact-in-form Lagrangian dynamical expression is proportional to the fourth power of the number of degrees of freedom (DOF) of a robotic system. This fact challenges both simulation and control of robots with hyper degrees of freedom. In this paper, a systematic approach for deriving the dynamical expression of so-called general constrained robots is proposed. This proposed approach has two main features. First, it uses the subsystem dynamics such as the dynamics of joints and rigid links to construct the dynamical expression of the entire robotic system in a closed form. The complexity of the resulted dynamic expression is linearly proportional to the number of DOF of a robotic system. Second, it extends the standard dynamical form and properties of the conventional single-arm constrained robots to a class of more general robotic systems including the coordinated multiple-arm robotic systems. Three spaces, namely the general joint space, the general task space, and the extended subsystems space, are connected through corresponding velocity/force mapping matrices.An erratum to this article can be found at 相似文献
32.
Jean-Claude Gauthier Gerd Brinkmann Bernie Copsey Michel Lecomte 《Nuclear Engineering and Design》2006,236(5-6):526-2004
Framatome ANP is developing a very high temperature reactor (VHTR), relying on its previous experience with high temperature reactor concepts, from its participation in the MODUL and the GT-MHR designs. While being a major actor in the nuclear reactor business with proven light water technology, AREVA wishes to be ready to meet the new challenges calling for small grid requirements, high temperature process heat and cogeneration. The Framatome ANP VHTR design for electricity production is based on an indirect cycle coupled to an “off-the-shelf” combined cycle gas turbine. Although direct cycle HTRs are being promoted for their high efficiency, preliminary evaluations show that the Framatome ANP design efficiency is on par with a direct cycle while avoiding power generation system (PGS) developments and keeping the PGS contamination free. Moreover, the nuclear heat source of the indirect cycle could also be used to meet the heat supplies from a standard design for multiple applications. 相似文献
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Salmain M Caro B Le Guen-Robin F Blais JC Jaouen G 《Chembiochem : a European journal of chemical biology》2004,5(1):99-109
Study of the reaction between the transition organometallic complex 4-ruthenocenyl 2,6-dimethylpyrylium tetrafluoroborate and the enzyme hen egg white lysozyme (HEWL) in solution and by diffusion in crystals was performed by use of a combination of spectroscopic and chromatographic methods. Conjugation involving the lysine residues of lysozyme appeared to occur readily, yielding very stable ruthenocenyl pyridinium adducts with average degrees of incorporation ranging from 0.2 to 1.8 metal complexes per protein molecule, depending on reaction conditions. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) revealed that the protein conjugates were in fact mixtures of unmodified, mono-, di- and sometimes tripyridinium adducts. In combination with reversed-phased HPLC, we were able to show that six different monoruthenocenyl pyridinium adducts were formed in solution. This result was confirmed by trypsin digestion of a ruthenocenyl pyridinium conjugate and MALDI-TOF MS analysis of the peptide mixture, which showed that lysines 1, 13, 33, 96, 97 and 116 were involved in the reaction with the pyrylium complex, lysines 13, 33 and 116 being the major binding sites. In the tetragonal crystal state, no binding of the ruthenium complex was shown to occur at lysine 116, owing to steric hindrance at this particular position. 相似文献
36.
Besnard Y Launay JC Guinet-Lebreton A Savourey G 《Computer methods and programs in biomedicine》2004,76(3):221-228
PREDICTOL is a PC program used to determine the thermophysiological duration limited exposures (DLE) in humans, nude or clothed, submitted to various climatic conditions (hot and cold climates) at rest or during a physical exercise. DLE are determined following different standards of the International Standardization Organization (ISO), especially ISO 7933 for hot environment and ISO-TR 11079 for cold environment. The original aspect of this program is that it can be used whatever the climatic conditions. The program presents two modes: an educational interactive mode and a scenario mode. The educational interactive mode demonstrates the thermophysiological effects, expressed as DLE, of different parameter changes (temperature, humidity, wind speed, metabolic heat production by physical exercise, clothing insulation and water vapor permeability). The scenario mode determines DLE for given various linked sequences as encountered in occupational, military or even recreational activities, each sequence being characterized by its climatic conditions, physical activities performed and by physical clothing properties. DLE given by PREDICTOL are correlated to those obtained in various controlled climatic laboratory conditions (r = 0.86; P < 0.001). PREDICTOL is written in Visual Basic 6.0. A "help menu" is provided to explain the use of the program and give information concerning the equations used to calculate both the thermal balance and DLE. 相似文献
37.
Jean-Claude Launay Gérard Villeneuve Michel Pouchard 《Materials Research Bulletin》1973,8(8):997-1005
Single crystals of V1?xNbxO2 ternary oxide (0 ? x ? 0,33) are prepared by chemical transport using TeCl4. The compositions are determined by thermogravimétric analysis under oxygen, X-ray diffraction measurements and evaluation of the insulator-metal transition temperature. 相似文献
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Foisel Hans-Martin Jaeger Monika Westphal F.-Joachim Ovsthus Knut Bischoff Jean-Claude 《Photonic Network Communications》2001,3(1-2):41-48
The commonly used IP-backbone network architecture of today is IP/ATM/SDH/WDM. This architecture has many redundant functionalities and is not optimized to transport IP traffic. New approaches for simplified network architectures try to eliminate redundant functionalities and to decrease the protocol overhead and thereby transport IP as efficiently as possible over WDM-based optical networks. EURESCOM project P918 Integration of IP-over-optical networks: networking and management investigated scenarios for optimized IP transport in WDM-based backbone networks. In this paper, three architectures, namely Gigabit Ethernet, Packet over Sonet/SDH and Dynamic Packet Transport are investigated and evaluated as an alternative to the IP/ATM/SDH/WDM architecture. 相似文献
40.
Carlo S. Iorio Oleg A. Kabov Jean-Claude Legros 《Microgravity science and technology》2007,19(3-4):27-29
In this paper, some of the preparatory experiments of the ESA sponsored space program CIMEX-1 are presented. A liquid layer of variable thickness is subject to a flow of inert gas. The non-uniform evaporation induced by the gas flow creates a temperature gradient parallel to the interface triggering in that way thermocapillary convection. The combined action of evaporation, thermocapillarity and gravity has been not completely clarified both theoretically and experimentally. The experiment presented in this work concerns a liquid layer of ethanol of 2.2 mm thickness in presence of a mass flow of Nitrogen whose intensity varies in the range of hundreds of milliliter per minute. The experiments were performed at an initial liquid temperature of 21°C. The patterns observed are strongly dependent on the flow rate of inert gas. A change in the instability patterns has been observed for a gas flow of about 1.7 l/min. 相似文献