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101.
Journal of Mechanical Science and Technology - This work reports on the position, velocity and acceleration analyses of a four-degrees-of-freedom parallel manipulator, 4-DoF-PM for brevity, which...  相似文献   
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In this paper, we assess the sensitivity of reactive tabu search to its meta-parameters. Based on a thorough experimental analysis of reactive tabu search applications to the quadratic assignment and the maximum clique problem, we show that its performance is relatively insensitive to its meta-parameters. This is particularly evident when compared to the sensitivity of tabu search to its parameters: tabu search is rather penalized if used with sub-optimal parameter settings. Reactive tabu search does not strongly pay its high parameter robustness in terms of performance, although it does not improve the peak performance of tabu search.  相似文献   
104.
Determining relationships between different types of quantum correlations in open composite quantum systems is important since it enables the exploitation of a type by knowing the amount of another type. We here review, by giving a formal demonstration, a closed formula of the Bell function, witnessing nonlocality, as a function of the concurrence, quantifying entanglement, valid for a system of two noninteracting qubits initially prepared in extended Werner-like states undergoing any local pure-dephasing evolution. This formula allows for finding nonlocality thresholds for the concurrence depending only on the purity of the initial state. We then utilize these thresholds in a paradigmatic system where the two qubits are locally affected by a quantum environment with an Ohmic class spectrum. We show that steady entanglement can be achieved and provide the lower bound of initial state purity such that this stationary entanglement is above the nonlocality threshold thus guaranteeing the maintenance of nonlocal correlations.  相似文献   
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Total microbial count reduction (TMR), total anthocyanins (TAR), and ascorbic acid retention (AAR) after the operation at different PAA concentrations (0–100 mg L?1), contact times (10–120 s), and temperatures (4–40°C) were used for multiple optimisation using Derringer′s desirability function. Two optimization scenarios (OP 1 and OP 2) were studied. OP 1 was proposed with the goal to maximize TMR with 90% TAR and AAR; and OP 2 maximizing TAR and AAR with TMR of 2 log UFC g?1. The optimized variable levels obtained were the following: 100 mg L?1 PAA, 24 °C and 50 s for OP 1 and 20 mg L?1 PAA, 18 °C and 52 s for OP 2. Additional validation experiments showed agreement between predicted and experimental results. OP 2 conditions are recommended to fresh‐cut strawberries washing disinfection because of an acceptable TMR, higher TAR and AAR, better sensory attributes, and the economic convenience of lesser PAA consumption.  相似文献   
108.
Application of the Peleg and Azuara et al. models for describing mass transfer during pile salting of goat sheets using different mixtures of NaCl, KCl, CaCl2 and MgCl2 was investigated The high coefficient of determination (R2 > 0.97 and R2 > 0.95 for Peleg and Azuara et al. models, respectively) and the modulus of mean relative errors (MRE < 10% for both models) indicated the acceptability of both Peleg and Azuara et al. models for predicting both moisture loss and salt uptake. The equilibrium moisture and salt contents were estimated using Peleg rate constants and Azuara et al. model parameters. Equilibrium moisture (xw) and salt contents (xs) varied from 0.522 to 0.860 g water/g db and from 0.311 to 0.352 g NaCl/g db respectively. Multiple comparison of means showed that xw and xs predicted by the Peleg model were lower than those estimated by the Azuara et al. model. The values differed by 1.86–13.6% for xw and by 1.13–10.57% for xs.  相似文献   
109.
In the present study, the chemical composition and antioxidant activities of Teucrium polium L. (Lamiaceae) were assessed. Fractionation of methanol extract obtained from the aerial parts of T. polium yielded one new phenylethanoid glycoside, named poliumoside B, together with four known flavonoids, two iridoid glycosides and a known poliumoside. The structures of all of these compounds were elucidated on the basis of spectroscopic data from 1D and 2D NMR experiments and MS spectral analyses. The antioxidant activities of the crude extracts and of the isolated compounds were evaluated through tests such as DPPH radical-scavenging capability, reducing power, xanthine oxidase inhibitory effect and inhibition of linoleic acid peroxidation. The highest antioxidant activity was found in the n-butanol extract, which also contained active polyphenols, thus suggesting that this plant could be used as a source of natural molecules, to provide safe antioxidant additives and nutraceuticals. The structure–activity relationships of the isolated compounds are also discussed.  相似文献   
110.
Universal Access in the Information Society - This paper preconizes the use of interactive environments as an accessible and inexpensive solution that allows supporting the recovery process of...  相似文献   
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