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51.
H. Oudadesse J. L. Irigaray Y. Barbotteau V. Brun Ph. Moretto 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):458-465
Bioactive glasses are used as coating biomaterials to facilitate anchorage of metallic prostheses implanted into the body. The aim of this work is to study the behavior of gel formed in contact with alloys and BVA and BVH bioactive glasses implanted. Cylinders of metallic implants composed by Ti, Al and V, are coated with bioactive glass. Three sheep were implanted for different time length: 3, 6 and 12 months in the femoral epiphysis. Results obtained with particle induced X-ray emission and scanning electron microscopy show that BVA coating induces a better contact between the metallic implant and bone. On the other hand, BVH coating prevents corrosion from the metallic implant. 相似文献
52.
Ph. MullhauptAuthor Vitae B. SrinivasanAuthor VitaeD. BonvinAuthor Vitae 《Automatica》2002,38(9):1565-1573
Analysis of exclusively kinetic two-link underactuated mechanical systems is undertaken in this paper. It is first shown that such systems are not full-state feedback linearizable around any equilibrium point. Also, the equilibrium points for which the system is small-time locally controllable (STLC) is at most a one-dimensional submanifold. A concept less restrictive than STLC, termed the small-time local output controllability (STLOC) is introduced, the satisfaction of which guarantees that a chosen configuration output can be controlled at its desired value. It is shown that the class of systems considered is STLOC, if the inertial coupling between the input and output is nonzero. Also, in such a case, the system is nonminimum phase. An example section illustrates all the results presented. 相似文献
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55.
Ph. A. Passeraub G. Rey-Mennet P. A. Besse H. Lorenz R. S. Popovic 《Sensors and actuators. A, Physical》1997,60(1-3):122-126
A high-sensitivity flat-coil inductive proximity sensor microsystem has been realized and successfully tested. The flat coil, made with CMOS-compatible post processes, is connected to a versatile differential relaxation oscillator electronic interface. In this new and simple interface, the excitation, the signal extraction and amplification are assured by only one operational amplifier. Experimental results on the microsystem confirm that large output frequency variations occur when a metallic target approaches the sensor. 相似文献
56.
For discontinuity analysis more and more sophisticated methods are used in the nuclear industry. The rapid development of computer technology offers the possibility to use imaging techniques. Instead of specialized focusing transducers the more flexible synthetic focusing techniques can be used. Presupposing that the material is ultrasonically isotropic and homogeneous, imaging techniques make it possible to visualize the reflectivity of the volume to be tested.Siemens developed the high speed holographic instrument Holo 3000 in cooperation with the University of Bochum. In this paper the method of Broad Band Holography is presented in the context of other imaging techniques.Different filtering methods have been investigated in order to achieve highest resolution and best signal to noise ratio with a given dataset. Different transducers respective wave modes have been applied to austenitic welds and claddings. The reconstructed image was evaluated using image processing techniques in order to investigate the possibilities to produce results easier to be quantifed than the original reconstruction.The results presented show a reliable expert tool for analysis measurements which also can be used for flaw detection. 相似文献
57.
G Appel A Briese K von Holleben G von Mickwitz M von Wenzlawowicz 《Canadian Metallurgical Quarterly》1995,102(6):233-234
It is reported on the fatal accident of a horse due to a cross-beam too low above the door of the stable, in which the animal suffered several skull fractures and a tear of the musculus longus capitis from the base of the skull. The aim of this article is, to supply a contribution to the establishment of minimal requirements for the housing of horses, in this case for the request of the minimum height of stable doors and ceilings as well as for constructions on horse transporters. On the grounds of this example, the natural behaviour of horses is discussed at the hand of the literature and the efforts are shown to improve the existing inadequacies in the housing and transport of horses with regard to the judicial situation. In the light of section 2 of the animal protection law, as to the construction of horse stables the importance is especially emphasized to consider the panic behaviour in connection with abrupt flight reactions as physiologic in the prevention of accidents. 相似文献
58.
Bafleur M. Vidal M. Puig Buxo J. Givelin Ph. Macary V. Sarrabayrouse G. 《Analog Integrated Circuits and Signal Processing》1995,8(3):219-231
To answer to the need of a cost effective smart power technology, an original design methodology that permits implementing latch-up free smart power circuits on a very simple CMOS/DMOS technology is proposed. The basic concept used to this purpose is letting float the wells of the MOS transistors most susceptible to initiate latch-up. The efficiency of the design methodology is experimentally shown. 相似文献
59.
60.
Eric P. Kvam Ph.D. Srikanth B. Samavedam B.Tech. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(3):47-51
The Ge-Si on Si epilayer system, besides being an interesting technological system in its own right, is a superb model for strained-layer studies. The point defect and symmetry defect structures associated with compound semiconductors can be avoided, allowing a focus on the mechanics of the system. Dislocation sources, glide behavior, and performance effects have been examined for strained-layer systems. Surprises have appeared along the way, but these materials are now becoming characterized well enough for industrial device applications. 相似文献