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131.
Chady Ghnatios Ghazi Asmar Elie Chakar Charbel Bou Mosleh 《Comptes Rendus Mecanique》2019,347(2):101-113
Automation is conquering new fields on a daily basis. Aiming for faster and more reliable products, industrials as well as researchers are oriented into automation. Non-destructive testing as well as defect quantification is not an exception. In fact, decisions with minimum allowable error are sought in real-time when facing any potential defect. In this work, we suggest a comprehensive method based on model order reduction techniques to judge if a structure shall be salvaged. The real-time decision is based on multidimensional parametric simulation, performed offline, using the Proper Generalized Decomposition (PGD). The PGD is a model order reduction technique that allows circumventing the curse of dimensionality by using domain decomposition. Therefore, the 6D simulation illustrated in this paper is performed within a few minutes on a standard laptop. Later on, a stress concentration manifold is built and used online for decision-making. The manifold is validated on a few selected solutions solved analytically using an analytical procedure. The aforementioned procedure is developed, in this paper, to calculate the tangential stress around circular holes of different sizes, in an infinite isotropic plate containing any number of holes and subjected to in-plane pressure loading at the tip of the infinite plate. The procedure is based on determining two Muskhelishvili complex potentials in terms of complex Fourier series, and applying the Schwartz alternating method repeatedly until the boundary conditions on the contour of every hole are satisfied. 相似文献
132.
Elie Sanchez 《Fuzzy Sets and Systems》1984,12(3):237-248
Assuming that 1 is any operation defined on a product set X × Y and taking values on a set Z, it can be extended to fuzzy sets by means of Zadeh's extension principle. Given a fuzzy subset C of Z, it is here shown how to solve the equation (or ) when a fuzzy subset A of X (or a fuzzy subset B of Y) is given. The methodology we provide includes, as a special case, the resolution of fuzzy arithmetical operations, i.e. when 1 stands for +, ?, × or ÷, extended to fuzzy numbers (fuzzy subsets of the real line). The paper is illustrated with several examples in fuzzy arithmetic. 相似文献
133.
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135.
Light activation leads to release of NO from a silicate sol-gel material SG-RuNO prepared from the ruthenium complex, [Ru(salen)(OH2)(NO)]+ (salen = N,N'-bis-(salicylidene)ethyl-enediaminato); after photochemical NO photolabilization, SG-RuNO can be regenerated from the spent material via the subsequent reaction with aqueous nitrite. 相似文献
136.
We identify a class of composite membranes: fluid bilayers coupled to an elastic meshwork that are such that the meshwork's energy is a function F(el)[A(xi)] not of the real microscopic membrane area A, but of a smoothed membrane's area A(xi), which corresponds to the area of the membrane coarse grained at the mesh size xi. We show that the meshwork modifies the membrane tension sigma both below and above the scale xi, inducing a steep crossover of amplitude deltasigma=dF(el)/dA(xi). The predictions of our model account for the fluctuation spectrum of red blood cell membranes coupled to their cytoskeleton. Our results indicate that the cytoskeleton might be under extensional stress, which would provide a means to regulate available membrane areas. We also predict an observable tension jump for membranes decorated with polymer "brushes." 相似文献
137.
L.?CalcagnileEmail author G.?Quarta M.?D’Elia 《Applied Physics A: Materials Science & Processing》2004,79(2):289-292
A new facility for accelerator mass spectrometry radiocarbon dating has been put in operation at the University of Lecce in southern Italy. The general features of the facility are described, showing how by the use of electrostatic and magnetic analyzers the radiocarbon content in several kinds of sample materials can be measured. The performances of the system are also given in terms of precision, accuracy and background. The results of the radiocarbon dating of two prehistoric sites are also reported. PACS 93.85.+q 相似文献
138.
Elie Sanchez 《Journal of Mathematical Analysis and Applications》1981,81(2):399-421
When R is a fuzzy relation between the elements of a finite set X, the fuzzy sets A of X such that R ° A = A (MAX-MIN composition) are called eigen fuzzy sets. The main result of this paper is the determination of the greatest eigen fuzzy set associated with a given fuzzy relation and we give three methods illustrated by an example. We then state that the greatest eigen fuzzy set associated with , the transitive closure of R, is exactly the one associated with R. Finally we describe how to obtain all fuzzy relations keeping invariant a given fuzzy set. 相似文献
139.
Stanislas Czernecki Constantin Georgoulis Elie Michel 《Journal of organometallic chemistry》1977,140(2):127-131
Butenylmagnesium, butenylzinc and butenylaluminium bromides are oxidized at low temperature (?80 and ?100°C). The qualitative and quantitative studies of the reaction products after reduction by PPh3, LiAlH4 and n-BuMgBr show that the secondary structure is dominant in the peroxides formed. 相似文献
140.
Guido Barone Giuseppina Castronuovo Vittorio Elia Massimo Muscetta 《Journal of solution chemistry》1986,15(2):129-140
The interaction in water of urea, monomethylurea, monoethylurea, monopropylurea, and monobutylurea with -cyclodextrin(hexacycloamylose) was studied calorimetrically at 25°C. The results show that the last three substances form inclusion complexes with -cyclodextrin. The enthalpy and the association constants relative to the inclusion process were determined. The association constant values are low, indicating weak complexing that increases with increasing length of the alkyl chain. Urea and monomethylurea, on the other hand, do not form inclusion complexes. For these systems the calorimetric data were treated in terms of excess enthalpies, and the McMillan-Mayer approach was used to get an insight into the weak, non-bonding molecular interactions occurring in these solutions.Presented at the sixth Italian meeting on Calorimetry and Thermal Analysis (AICAT) held in Naples, December 4–7, 1984. 相似文献