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191.
Josef Reiser 《Electrical Engineering (Archiv fur Elektrotechnik)》1934,28(7):447-454
Ohne ZusammenfassungSiemens-Z. 1929 S. 565. 相似文献
192.
Josef Adorján 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1911,22(5):297-300
Ohne ZusammenfassungMitteilung aus der Kgl.-Ungarischen Agrikulturchemischen Versuchstation in Debreczin. 相似文献
193.
Formation of deposits from liquid foods on heated surfaces during heating and evaporation . In the past, deposit formation on heated surfaces in food processing has been investigated by considering the whole of the deposited material. This precluded reaction kinetic studies and it was therefore impossible to introduce preventive measures. However, ultrafiltration of milk and whey has now furnished model systems in which deposit formation by proteins and salts can be studied separately. The tendency for deposit formation of proteins is similar to the denaturation reaction of whey proteins. The heat sensitive native proteins in the liquid are deposited preferentially on surfaces already covered with reactive proteins. The deposition of milk salts is determined by the degree of supersaturation of the solution. For milk salts deposition, an activation energy was found which is typical for diffusion processes. 相似文献
194.
Amy E. Battles Benjamin M. Linder Kenneth W. Chang Alexander H. Slocum 《Precision Engineering》1993,15(4):248-257
The performance of bilaminar resonating transducers depends on the thickness and uniformity of the transducer's bond layers. Optimal resonant performance requires a bond thickness between the crystals of ≤5 μm. In addition, a later product assembly step requires precise alignment between each of the transducer components. This article describes a precision tool, designed and built for an industrial sponsor, for assembling these transducers. The tool consists of a screen printer and a press. The screen printer includes a stencil and a powered squeegee cart that rides on a bearing rail. The press contains a bellows that applies pressure, as well as two vacuum heads that hold transducer components in place while pressure is applied. Precision design techniques, such as the use of kinematic couplings and flexures, were used throughout the tool. Bond thicknesses of assembled transducers were evaluated by inspecting each transducer's cross-section with a scanning electron microscope. Preliminary results in indicate that the requirement for a bond thickness of <5 μm was easily achieved; most thicknesses were an optimal 1 μm. 相似文献
195.
Between January 1st 1992 and December 31st 1993 140 non-complex (i.e. nerve, vascular, tendon injuries) fractures of the peripheral hand skeleton were operated at the Policlinic of the Kantonsspital Basel. In a retrospective study we analyzed results, complications and absence from work. We treated 110 male and 30 female patients with a mean age of 47 years. 45 fractures were treated by plate fixation, 45 by screw fixation, 53 times we applied k-wires and once a mini-fix-ex (AO-Prototype). Plate and screw fixation were performed with AO-mini-implants. 90% of our patients had an uneventful postoperative course. In spite of functional after-treatment we noted in 8.6% of the patients a relevant loss of movement leading to operative tenolysis in 7 patients. Fractures at the level of PIP were most frequently associated with loss of movement. Absence from work was 59 days in average (1-206)! Conclusions: Peripheral osteosynthesis of the hand (non-complex) are effectively treated on an out-patient basis. In spite of functional after-treatment about 10% of patients have a relevant postoperative reduction in motility. Absence from work is relatively long after operative treatment of peripheral hand fractures. 相似文献
196.
197.
Estimation of complex multimodal motion: an approach based on robust statistics and Hough transform 总被引:1,自引:0,他引:1
An application of robust statistics in a Hough transform based motion estimation approach is presented. The algorithm is developed and experiments are performed, proving its superior performance in terms of estimate accuracy, convergence, robustness and better segmentation. Comparative results with standard methods are also included. 相似文献
198.
OBJECTIVES: To examine macro- and microscopic characteristics of cartilage of the distal phalanx (ungual cartilage [UC]) and digital cushion in the equine foot and to relate them to the foot's function of energy dissipation. ANIMALS: 85 horses and 5 foals of various breeds and ages. PROCEDURE: Feet, obtained at necropsy, were perfused with India ink (n = 30), latex (5), or polymer plastic (10). Select feet were examined histologically for tissue architecture and to identify elastic fibers. Immunochemistry to identify substance P peptides in nerves (feet from foals) and gold chloride impregnation of axons (n = 10) were performed. Feet were sectioned transversely (n = 27) or coronally (62 feet in a matched-paired study). Ungual cartilage was measured at the navicular bone. Digital cushions were examined for relative tissue composition between forefeet and hind feet. RESULTS: Ungual cartilage formed an axial projection that extended towards the midline to overlie the bars, and dorsally along the semilunar line of the distal phalanx. Ungual cartilage of forefeet was significantly larger than that of hind feet. The digital cushion was composed of fat and elastic tissues in feet with thin UC, or fibrous and fibrocartilaginous tissue and elastic tissue in feet with thicker UC. Sensory nerves and an extensive network of venovenous anastomoses were found in the UC. CONCLUSIONS AND CLINICAL RELEVANCE: Ungual cartilage and the digital cushion provide the basis for a hemodynamic flow hypothesis of energy dissipation. Maximum energy dissipation depends on proper hoof preparation and shoeing. 相似文献
199.
Josef Bigün 《Computer Vision and Image Understanding》1997,68(3):290-307
A theory for detecting general curve families by means of symmetry measurements is presented. Symmetries are modeled by iso-gray curves of conjugate harmonic function pairs which define coordinate transformations. Harmonic function pair coordinates render the target curve patterns as parallel lines, which is defined here as linear symmetry. Detecting these lines, or generalized linear symmetry fitting, corresponds to finding invariants of Lie groups of transformations. A technique based on total least square error minimization for estimating the invariance parameters is presented. It uses the Lie infinitesimal operators to construct feature extraction methods that are efficient and simple to implement. The technique, which is shown to be an extension of the generalized Hough Transform, enables detection by voting and accumulating evidence for the searched pattern. In this approach complex valued votes are permitted, where the phase of the vote identifies the member of the family of patterns that are detectable. Experimental results illustrating the theory and its application to real as well as synthetic images are presented. 相似文献
200.
A new modification of Kaliski's algorithm for computing the Almost Montgomery Inverse, optimized for implementation in hardware, is presented. The algorithm and the corresponding portion of the hardware architecture overcome certain drawbacks of the currently used methods. In particular, the “less than/greater than” tests that represent subtractions are avoided. 相似文献