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91.
For dynamically measuring position in three degrees of freedom laser tracking systems are well known. Up to now no possibility to measure also orientation using the same laser beam has been known. We present a technique to incorporate orientation measurement into a laser tracking system that requires only minor changes in the existing hardware. The method is based on the analysis of an image of the reflected laser beam intensity distribution. In this image the edges of a slightly modified retroreflector represent a function of the orientation of the end-effector holding the retroreflector. It is shown that from this image the orientation can be determined uniquely and in real time.
A laser tracking system including position and orientation measurement constitutes an instrument to accurately determine robot performance as well as to acquire hints on how to improve robot models and control algorithms. 相似文献
92.
U. Johann W. Reiland 《International Journal of Satellite Communications and Networking》1988,6(2):225-230
An experimental optical communications link between two stratospheric balloons is proposed as an intermediate step from limited ground laboratory tests to costly space operations. Such an experiment can overcome many environmental constraints encountered on the ground, and allows all measurements to be made directly in the antenna far field. Early performance demonstrations are possible which allow experimental trade-offs between alternative technologies and the verification of concepts, critical system parameters and subfunctions under near space conditions. 相似文献
93.
Johann Blieberger 《Information and Computation》2001,171(2):156
The purpose of this paper is to show that indirect recursive procedures can be used for implementing real-time applications without harm, if a few conditions are met. These conditions ensure that upper bounds for space and time requirements can be derived at compile time. Moreover they are simple enough such that many important recursive algorithms can be implemented. In addition, our approach allows for concentrating on essential properties of the parameter space during space and time analysis. This is done by morphisms that transfer important properties from the original parameter space to simpler ones, which results in simpler formulas of space and time estimates. 相似文献
94.
95.
Dr. Johann Bizer 《Datenschutz und Datensicherheit - DuD》2006,30(10):598-598
96.
Johann Bizer 《Datenschutz und Datensicherheit - DuD》2007,31(4):264-266
Auf Einladung des Innenausschusses des Deutschen Bundestages fand am 5. M?rz 2007 eine ?ffentliche Anh?rung zum Thema der
Modernisierung des Datenschutzes statt. Gegenstand waren Entschlie?ungsantr?ge der Fraktionen der FDP sowie von Bündnis90/Die
Grünen zum Datenschutzaudit sowie zum Scoring und zu Auskunftspflichten bei Datenschutzpannen. Stellung genommen hat für das
Unabh?ngige Landeszentrum für Datenschutz Schleswig-Holstein Johann Bizer. Das ULD erm?glicht bereits heute die Zertifizierung
von Gütesiegeln und Auditverfahren. 相似文献
97.
98.
B Johann 《Canadian Metallurgical Quarterly》1997,115(27):38-42
Transplantation represents a breaching of the bodily integrity of the patient, and can lead to anxiety, depression and an identity problem. In the post-transplantation phase also, the patient undergoes further stress associated with check examinations and treatment. Standardized surveys show that the fear of graft rejection remains with the patient for the rest of his/her life. The new situation also has an influence on partnership, family and the overall psychosocial setting. All this adds up to a need for psychosomatic care, support and, where indicated, appropriate treatment in every transplantation patient. The broad spectrum of possible measures available in this connection is discussed. 相似文献
99.
100.
Schwaiger K Helmke K Hölzel CS Bauer J 《International journal of food microbiology》2011,148(3):191-196
The aim of this study was to elucidate whether and to what extent fresh produce from Germany plays a role as a carrier and reservoir of antibiotic resistant bacteria. For this purpose, 1001 vegetables (fruit, root, bulbous vegetables, salads and cereals) were collected from 13 farms and 11 supermarkets in Germany and examined bacteriologically. Phenotypic resistance of Enterobacter cloacae (n = 172); Enterobacter gergoviae (n = 92); Pantoea agglomerans (n = 96); Pseudomonas aeruginosa (n = 295); Pseudomonas putida (n = 106) and Enterococcus faecalis (n = 100) against up to 30 antibiotics was determined by using the microdilution method. Resistance to ß-lactams was most frequently expressed by P. agglomerans and E. gergoviae against cefaclor (41% and 29%). Relatively high resistance rates were also observed for doxycycline (23%), erythromycin (21%) and rifampicin (65%) in E. faecalis, for spectinomycin (28%) and mezlocillin (12%) in E. cloacae, as well as for streptomycin (19%) in P. putida. In P. aeruginosa, relatively low resistance rates were observed for the aminoglycosides amikacin, apramicin, gentamicin, neomycin, netilmicin and tobramycin (< 4%); 11% was resistant to streptomycin. No glycopeptide-resistant enterococci were observed. Resistance rates of bacteria isolated from farm samples were higher than those of the retail markets whenever significant differences were observed. This suggests that expressing resistance is at the expense of bacterial viability, since vegetables purchased directly at the farm are probably fresher than at the supermarket, and they have not been exposed to stress factors. However, this should not keep the customer from buying directly at the farm, since the overall resistance rates were not higher than observed in bacteria from human or animal origin. Instead, peeling or washing vegetables before eating them raw is highly recommended, since it reduces not only the risk of contact with pathogens, but also that of ingesting and spreading antibiotic resistant bacteria. 相似文献