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101.
Serge A. Shapiro Susanne Rentsch Elmar Rothert 《Canadian Metallurgical Quarterly》2005,131(9):947-952
Operations including borehole fluid injections are typical for exploration and development of hydrocarbon or geothermic reservoirs. Microseismicity occurring during such operations has a large potential for understanding physics of the seismogenic process as well as in obtaining detailed information about reservoirs at locations as far as several kilometers from boreholes. We propose that the phenomenon of microseismicity triggering by borehole fluid injections is related to the process of the Frenkel–Biot slow wave propagation. In the low-frequency range (hours or days of fluid injection durations) this process reduces to the pore-pressure diffusion. We search for diffusion-related features of induced microseismicity. Two types of such signatures are considered. The first one is related to the geometry of microseismic clouds. Another type of signature is related to the probability of microearthquakes. On this basis we introduce a concept for interpretation of microseismic data which provides a possibility to infer information about hydraulic properties of rocks. Such information can be of significant importance for industrial applications and for understanding physical properties of geological structures. 相似文献
102.
On a Kernel-Based Method for Pattern Recognition, Regression, Approximation, and Operator Inversion 总被引:17,自引:0,他引:17
We present a kernel-based framework for pattern recognition, regression estimation, function approximation, and multiple
operator inversion. Adopting a regularization-theoretic framework, the above are formulated as constrained optimization problems.
Previous approaches such as ridge regression, support vector methods, and regularization networks are included as special
cases. We show connections between the cost function and some properties up to now believed to apply to support vector machines
only. For appropriately chosen cost functions, the optimal solution of all the problems described above can be found by solving
a simple quadratic programming problem.
Received January 31, 1997; revised June 1, 1997, and July 7, 1997. 相似文献
103.
Golovko DS Haschke T Wiechert W Bonaccurso E 《The Review of scientific instruments》2007,78(4):043705
We present here an experimental setup and suggest an extension to the long existing added-mass method for the calibration of the spring constant of atomic force microscope cantilevers. Instead of measuring the resonance frequency shift that results from attaching particles of known masses to the end of cantilevers, we load them with water microdrops generated by a commercial inkjet dispenser. Such a device is capable of generating drops, and thus masses, of extremely reproducible size. This makes it an ideal tool for calibration tasks. Moreover, the major advantage of water microdrops is that they allow for a nearly contactless calibration: no mechanical micromanipulation of particles on cantilevers is required, neither for their deposition nor for removal. After some seconds the water drop is completely evaporated, and no residues are left on the cantilever surface or tip. We present two variants: we vary the size of the drops and deposit them at the free end of the cantilever, or we keep the size of the drops constant and vary their position along the cantilever. For the second variant, we implemented also numerical simulations. Spring constants measured by this method are comparable to results obtained by the thermal noise method, as we demonstrate for six different cantilevers. 相似文献
104.
Bettina?Sch?ne-SeifertEmail author Daniel?R.?Friedrich Anke?Harney Stefan?Huster Heiner?Raspe 《Ethik in der Medizin》2018,30(4):325-341
Definition of the problem
“Medical necessity” (MedN) is the central regulatory concept for decisions about which services are covered by German statutory health insurance. Despite its seeming objectivity and dependence on physicians’ expert judgment, the concept is by no means clearly defined.Arguments
In this first of five planned papers on the conceptual analysis of MedN from the perspectives of philosophy and ethics of medicine, law, and (social) medicine, the focus lies on systemizing ongoing controversies.Conclusion
Our goal is to come up with a so far missing foundation for detailed debates. We aim to clarify MedN’s conceptual structure, function, contextuality, and ambiguities as well as the fundamental limits of conceptual investigations for the normative questions at issue of regulating medical services.105.
Carlos Raniery Paula dos Santos Jeroen Famaey Jürgen Schönwälder Lisandro Zambenedetti Granville Aiko Pras Filip De Turck 《Journal of Network and Systems Management》2016,24(3):764-787
Network and service management has established itself as a research field in the general area of computer networks. However, up to now, no appropriate organization of the field has been carried out in terms of a comprehensive list of terms and topics. In this paper, we introduce a taxonomy for network and service management. With such a taxonomy, it is possible to better understand the landscape of research as well as to reason about possible future challenges and opportunities. As such, in addition to the taxonomy itself, we also present an initial analysis of the field’s past, present, and future, based on the records of papers submitted and accepted in major conferences in the area, as well as a site survey performed through a questionnaire answered by experts from both industry and academia. 相似文献
106.
107.
C. Hassel K. Blaum T. Day Goodacre H. Dorrer Ch. E. Düllmann K. Eberhardt S. Eliseev C. Enss P. Filianin A. Fäßler A. Fleischmann L. Gastaldo M. Goncharov D. Hengstler J. Jochum K. Johnston M. Keller S. Kempf T. Kieck U. Köster M. Krantz B. Marsh C. Mokry Yu. N. Novikov P. C. O. Ranitzsch S. Rothe A. Rischka J. Runke A. Saenz F. Schneider S. Scholl R. X. Schüssler F. Simkovic T. Stora P. Thörle-Pospiech A. Türler M. Veinhard M. Wegner K. Wendt K. Zuber 《Journal of Low Temperature Physics》2016,184(3-4):910-921
108.
Markus Wohlschlögel Rainer Steegmüller Andreas Schüßler 《Journal of Materials Engineering and Performance》2014,23(7):2635-2640
Nonmetallic inclusions in Nitinol, such as carbides (TiC) and intermetallic oxides (Ti4Ni2O x ), are known to be triggers for fatigue failure of Nitinol medical devices. These mechanically brittle inclusions are introduced during the melting process. As a result of hot and cold working in the production of Nitinol tubing inclusions are fractionalized due to the mechanical deformation imposed. While the role of inclusions regarding Nitinol fatigue performance has been studied extensively in the past, their effect on Nitinol corrosion behavior was investigated in only a limited number of studies. The focus of the present work was to understand the effect of inclusion size and distribution on the corrosion behavior of medical-device grade Nitinol tubing made from three different ingot sources during different manufacturing stages: (i) for the initial stage (hollow: round bar with centric hole), (ii) after hot drawing, and (iii) after the final drawing step (final tubing dimensions: outer diameter 0.3 mm, wall thickness 0.1 mm). For one ingot source, two different material qualities were investigated. Potentiodynamic polarization tests were performed for electropolished samples of the above-mentioned stages. Results indicate that inclusion size rather than inclusion quantity affects the susceptibility of electropolished Nitinol to pitting corrosion. 相似文献
109.
Organic coatings in the automobile industry have to resist corrosion and mechanical damage from stone chipping. Currently, no tool is established in industrial non‐destructive applications for analyzing the damage of stone‐impacts and the following corrosion after accelerated corrosion tests. Measurement methods such as the scanning Kelvin probe can analyze the corrosion progress in a detailed manner, but with a long measurement time. The pulsed phase thermography (PPT) is a non‐destructive tool to analyze inhomogeneities and defects in materials, with a huge field of applications existing. The present work shows advances in using the PPT to detect propagation of corrosion under coatings. Physical principles of the mechanism of the corrosion detection under coatings are described. Results of measurements of organic coatings on carbon steel as well as of organic coated galvanized steel show the corrosion propagation. Influencing factors to the measurement such as the thickness of the coatings are investigated, but no significant effect on the quality of the analysis was found. The corrosion progress can be monitored by the PPT fast and reliably. The achieved results correlate with the theoretical basis and the test results after surface characterization and destructive analysis of samples. 相似文献
110.
Qamer Zia Davide Tranchida René Androsch Holger Schönherr 《Journal of Materials Science》2012,47(7):3040-3045
In this study the effects of crystal habit, crystallinity and superstructure on the modulus of elasticity of isotactic polypropylene
films were analyzed by atomic force microscope (AFM) nanoindentation. The modulus of elasticity, evaluated on the nanometer
scale by AFM, showed a qualitatively similar dependence on the crystal habit, crystallinity and superstructure as the modulus
of elasticity measured by dynamic-mechanical analysis and tensile testing. The observed values of both the surface stiffness
measured by AFM and the macroscopic/bulk stiffness were distinctly larger in the presence of non-isometric lamellae organized
in spherulite than in the presence of isometric nodular crystals, not organized in a spherulitic superstructure. The experimental
data showed that the modulus of elasticity is not primarily influenced by the presence or absence of spherulite but by the
molecular-deformation constraint associated to the crystal habit. 相似文献