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71.
Fuzzy identification of cutting acoustic emission with extended subtractive cluster analysis 总被引:1,自引:0,他引:1
This paper presents fuzzy acoustic emission identification in high precision hard turning process based on extended subtractive
cluster analysis combined with the least-square estimation method. The fuzzy identification method provides a simple way to
arrive at a definite conclusion based upon the information obtained with the difficulty in understanding the exact physics
of the machining process. The experimental results prove that the proposed method is efficient and feasible. 相似文献
72.
Tharwat Mohy El Dine David Evans Prof. Jacques Rouden Dr. Jérôme Blanchet 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):5894-5898
A highly efficient and mild transamidation of amides with amines co‐catalysed by borinic acid and acetic acid has been reported. A wide range of functionalised formamides was synthesized in excellent yields, including important chiral α‐amino acid derivatives, with minor racemisation being observed. Experiments suggested that the reaction rely on a cooperative catalysis involving an enhanced boron‐derived Lewis acidity rather than an improved Brønsted acidity of acetic acid. 相似文献
73.
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75.
Oliver Salazar Celis Annie Cuyt Dirk Deschrijver Dries Vande Ginste Tom Dhaene Luc Knockaert 《Applied Mathematical Modelling》2013
In this paper a novel macromodeling scheme is presented to model the per unit of length (p.u.l.) parameters of uniform transmission lines. In particular, it is focused on single on-chip interconnects, because their p.u.l. parameters are influenced by the presence of semiconductor (s) and as such exhibit a strong frequency-dependency, making the modeling process harder. Starting from a set of very accurate tabulated data samples, obtained by two-dimensional electromagnetic modeling, rational models for the four p.u.l. parameters are constructed. The novelty of the approach lies in the fact that the rational models are positive by construction and that a controllable accuracy is obtained. These models can then further be used to construct multivariate models, e.g., for variability analysis. Here, the novel scheme is applied to an on-chip inverted embedded microstrip line, of which the signal integrity behavior is assessed in both the frequency and the time domain, demonstrating the applicability of the macromodels. 相似文献
76.
This paper proposes a set-membership approach to characterize the kernel of an interval-valued function. In the context of a bounded-error estimation, this formulation makes it possible to embed all uncertainties of the problem inside the interval function and thus to avoid bisections with respect to all these uncertainties. To illustrate the principle of the approach, two testcases taken from robotics will be presented. The first testcase deals with the characterization of all loops of a mobile robot from proprioceptive measurements only. The second testcase is the localization of a robot from range-only measurements. 相似文献
77.
Taratra André Fenoradosoa Céline Laroche Cedric Delattre Virginie Dulong Didier Le Cerf Luc Picton Philippe Michaud 《Applied biochemistry and biotechnology》2012,167(5):1303-1313
The rheological behavior of a sulfated galactan extracted from Halymenia durvillei, a red seaweed collected in the coastal waters of a small island of Madagascar (Nosy-be in Indian Ocean), was investigated in dilute and semi-dilute solutions. In dilute solution with NaCl at 0.3?M, the polysaccharide adopted a coil conformation whereas, at higher concentrations, the polymer had the behavior of shear-thinning fluid, typical of polymer with high molar mass or semi-rigid conformation. Degradations of this lambda carrageenan-like, using radical depolymerization, and high-pressure homogenization led to several samples of various and controlled molar masses. The measure of their intrinsic viscosities permitted the determination of the relationship of Mark?CHouwink?CSakurada. 相似文献
78.
Yannick Vercammen Jaymes Van Luppen Christiaan Van Roost Roel De Mondt Frank Vangaever Luc Van Vaeck 《Analytical and bioanalytical chemistry》2013,405(6):2053-2064
Molecular depth profiling is needed to develop high-tech materials optimised to the μm or even up to the nm scale. Recent progress in time-of-flight static secondary ion mass spectrometry (ToF-S-SIMS) offers perspectives to molecular depth profiling. However, at this moment, the methodology is not yet capable to deal with a range of materials science applications because of the limited depth range, the loss of intensity in the subsurface and the loss of depth resolution at large distances from the original surface. Therefore, the purpose of this paper is to develop a complementary approach for the molecular 3D analysis at large depth, using a combination of ultra-low angle microtomy (ULAM) and surface analysis of the sectioned material with ToF-S-SIMS. Single inkjet dots with a diameter of 100 μm and height of 22 μm on a PET substrate have been used as a test system for the methodology. It is demonstrated that the use of a diamond knife allows the molecular composition and distribution of components within the microscopic feature to be probed with a lateral resolution of 300 nm. Hence the methodology approaches the physical limit for ion imaging of organic components with local concentrations in the % range. In practice, the achievable depth resolution with ULAM-S-SIMS is ultimately limited by the surface roughness of the section. Careful optimisation of the ULAM step has resulted in a surface roughness within 6 nm (R a value) at a depth of 21 μm. This offers perspective to achieve 3D analysis with a depth resolution as good as 18 nm at such a large distance from the surface. Furthermore, the ULAM-S-SIMS approach is applicable to materials unamenable to ion beam erosion. However, the method is limited to dealing with, for instance, Si or glass substrates that cannot be sectioned with a microtomy knife. Furthermore, sufficient adhesion between stacked layers or between the coating and substrate is required. However, it is found that the approach is applicable to a wide variety of industrially important (multi)layers of polymers on a polymer substrate. 相似文献
79.
Dr. György Szalóki Prof. Jean‐Luc Pozzo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(34):11124-11132
Diarylethenes possess unique structural properties, which enabled them to find widespread applications in the field of photochromism. Nowadays, bisthienylcyclopentenes (BTCs) present the most popular subfamily of these compounds, which are widely used as P‐type chromophores. This minireview summarises the main strategies for the synthesis of symmetrical and nonsymmetrical BTCs. In addition, attention is drawn to desymmetrisations achieved by monosubstitutions, which is not frequently utilised, although it can be highly advantageous. This is supported with some of the authors’ latest results. 相似文献
80.
Fabián Flores-Bazán Dinh The Luc Antoine Soubeyran 《Journal of Optimization Theory and Applications》2012,155(3):883-901
We study reference-dependent preference relations defined by a real-valued bivariate function and prove an existence criterion for maximal elements. Then we formulate a generalized version of the well-known Brondsted maximum principle and apply it to behavioral traps and Nash equilibrium in games with preference relations that are not necessarily partial orders. 相似文献