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81.
Motivated by the collection outsourcing phenomena under Extended Producer Responsibility (EPR), this paper studies a contract design problem for a manufacturer who consigns the used product collection to a collector, while the manufacturer only has incomplete information on the collector's cost. On the basis of the incentive theory, optimal contracts are developed to minimize the cost and satisfy the collection constraints prescribed by EPR. Properties of the contract parameters are derived, and issues such as information rent and information value are also explored. The impacts of EPR are analysed by comparing whether or not EPR law is implemented, and more managerial insights are further obtained through numerical examples. 相似文献
82.
Oxide ion conductivity of the pure and aliovalent ion substituted rare-earth pyrohafnates in the series RE2−xSrxHf2O7 and RE2Hf2−xAlxO7 (RE=Gd and Nd; x=0–0.2) has been explored in the temperature range 400°C–700°C for the first time. It is seen that, conductivity is enhanced by doping 5 atom% Sr at the rare–earth site in these systems. Well defined impedance plots due to grain interior and grain boundary resistances were obtained in the Gd pyrohafnate with Sr substitution. The results of the conductivity variation for the pure, Sr and Al doped phases are explained on the basis of pyrochlore structure. 相似文献
83.
Amperometric measurement of superoxide dismutase (SOD) was carried out at cytochrome c-immobilized monolayers and ascorbate oxidase (AOD)/xanthine oxidase (XOD)/cytochrome c- and (AOD, XOD)/cytochrome c-multilayers. Cytochrome c was covalently immobilized on mercaptopropionic acid-containing self-assembled monolayers on gold. A biopolymer membrane of poly-L-lysine confining XOD and AOD was cast on the monolayer of cytochrome c. While both the cytochrome c-immobilized monolayer and multilayer electrodes show anodic current responses to the generation of superoxide radical, the sensitivity of the multilayer system for the detection of superoxide radical was high relative to that of the monolayer system. In the case of the cytochrome c-multilayer electrodes, the generation of superoxide radical near the sensing element, cytochrome c, resulted in high sensitivity for the detection of superoxide. The use of a XOD and AOD-incorporated poly-L-lysine membrane enabled the detection of the generation of superoxide radical in the presence of L-ascorbic acid. Though L-ascorbic acid could scavenge superoxide radical, the biopolymer membrane confined with AOD will oxidize any L-ascorbic acid that permeated into the membrane. By using the multilayer electrodes, one could measure the activity of SOD in the presence of L-ascorbic acid. 相似文献
84.
A fiber optic sensor for determining the thickness of a transparent plate (1–2.5 mm) is described based on a fiber optic displacement sensor. The sensor characteristics are found to vary with the change in the thickness of a plate. A theoretical model is proposed and validated with experimental results. The behavior of the sensor is evaluated and analyzed in terms of the numerical aperture and diameter of the fiber. 相似文献
85.
86.
If a connected component of perfect equilibria of a two-player game contains a stable set as defined by Mertens, then the
component is itself stable. Thus the stable sets maximal under inclusion are connected components of perfect equilibria.
Received: October 1999/Revised: February 2001 相似文献
87.
In this paper, we construct an invariant metric in the space of homogeneous polynomials of a given degree (≥3). The homogeneous
polynomials specify a nonlinear symplectic map which in turn represents a Hamiltonian system. By minimizing the norm constructed
out of this metric as a function of system parameters, we demonstrate that the performance of a nonlinear Hamiltonian system
is enhanced. 相似文献
88.
Thermal rearrangement of diethylamino-5-(m-methoxyphenoxy)-pent-2-yne (3) gives 1-(m-methexyphenoxy)-pent-3,4-diene (14) in about 8% yield. Hydration of the latter yields 1-(m-methoxyphenoxy)-pentan-4-one (6), which has been synthesised by an unambiguous route. A mechanism of formation of the allene (14) from the amine (3) has been suggested. 相似文献
89.
The question whether the human cardiac system is chaotic or not has been an open one. Recent results in chaos theory have shown that the usual methods, such as saturation of correlation dimension D(2) or the existence of positive Lyapunov exponent, alone do not provide sufficient evidence to confirm the presence of deterministic chaos in an experimental system. The results of surrogate data analysis together with the short-term prediction analysis can be used to check whether a given time series is consistent with the hypothesis of deterministic chaos. In this work nonlinear dynamical tools such as surrogate data analysis, short-term prediction, saturation of D(2) and positive Lyapunov exponent have been applied to measured ECG data for several normal and pathological cases. The pathology presently studied are PVC (Premature Ventricular Contraction), VTA (Ventricular Tachy Arrhythmia), AV (Atrio-Ventricular) block and VF (Ventricular Fibrillation). While these results do not prove that ECG time series is definitely chaotic, they are found to be consistent with the hypothesis of chaotic dynamics. (c) 1998 American Institute of Physics. 相似文献
90.
P. Govindan A. Palamalai K. S. Vijayan S. Subbuthai S. Murugesan S. V. Mohan R. V. Subba Rao 《Journal of Radioanalytical and Nuclear Chemistry》2002,254(1):65-70
Ammonium uranyl carbonate (AUC) precipitation is developed for the conversion of uranyl nitrate to oxide in the uranium reconversion step of reprocessing of irradiated fuel by the addition of ammonium carbonate salt. Different precipitation conditions of AUC are studied. The solubility of AUC as a function of uranium concentration in the feed at different temperatures using ammonium carbonate salt as precipitant is studied. This study indicates that 95-99.8% of uranium is recovered as AUC by precipitating 5-125 g/l of uranium with loss of uranium (250-10 ppm) in the filtrate by adding ammonium carbonate salt. It is also observed that the solubility of AUC increased as the concentration of uranium decreased. Thermal decomposition is carried out by thermogravimetry/differential thermal analysis (TG/DTA) and evolved gas analysis-mass spectrometry (EGA-MS) to find out AUC decomposition and gases evolved during decomposition. Studies are also carried out to characterize AUC by using X-ray diffraction (XRD). The data show that AUC obtained by the above conditions is very much consistent with published information. 相似文献