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341.
Florin O. Bilbiie 《Journal of Optimization Theory and Applications》2011,150(3):657-674
A prominent solution to the time-inconsistency problem inherent to monetary policymaking consists of delegating monetary policy
to an independent central bank by an appropriately designed inflation contract or target. This paper shows that delegation
is not a solution to this problem: optimal delegation requires commitment and is not time-consistent, while time-consistent delegation is suboptimal. We prove these
results formally in a popular dynamic model of monetary policy. Introducing costs of reappointing the central banker can only
solve this problem if the government is infinitely averse to changing central bank’s contract. 相似文献
342.
Maria A. Zoran Mariana Rodica Dida AlexandraTeodora Zoran Liviu Florin Zoran Adrian Dida 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(3):1179-1192
Air quality monitoring could potentially improve exposure estimates for use in epidemiological studies. We investigated air quality by monitoring concentrations of 222Rn near the ground and particulate matter (PM) with an aerodynamic diameter less than or equal to 10 μm (PM10) and 2.5 μm (PM2.5) for Bucharest-Magurele periurban area. Atmospheric radon concentrations have been continuously monitored near the ground at 1 m height as well as at 10 m height. This paper presents time-series of radon concentrations monitoring in air near the ground measured during 1 January 2011–1 January 2012 by use of solid state nuclear track detectors SSNTD CR-39, exposed for 10 days periods. The daily average atmospheric radon concentration near the ground registered at 1 m height was found to be in range of 40.25 ± 7.53 Bq/m3, which was comparable with the daily average radon concentration of 44.92 ± 9.94 Bq/m3 recorded for period 1 August 2011–20 December 2011 at 10 m height by AlphaGUARD Radon monitor. Also, was done a comparative analysis of spatio-temporal variations in time series of outdoor radon concentration and PM in two size fractions (PM10 and PM2.5) in Bucharest Magurele area for 2011 year. The predominant recorded component in PM10 was PM2.5. Observational results show that recorded yearly average PM2.5 and PM10 concentrations were 35.96 μg/m3 and 40.91 μg/m3, respectively. The average ratio of PM2.5/PM10 was 87.9 % at this sampling site. However, in densely populated Bucharest urban and suburban areas the mean daily EC limit values for PM10, PM2.5 and attached 222Rn are frequently exceeded leading to serious public concern during the last years. The ambient air pollution measurements like as PM10 and PM2.5 levels are used as a proxy for personal exposure levels. Have been investigated also meteorological effects on the temporal patterns of atmospheric radon and particle matter. 相似文献
343.
Augusta Raiu Ana‐Maria Acu Tuncer Acar Daniel Florin Sofonea 《Mathematical Methods in the Applied Sciences》2019,42(16):5133-5142
The present paper deals with a new positive linear operator which gives a connection between the Bernstein operators and their genuine Bernstein‐Durrmeyer variants. These new operators depend on a certain function τ defined on [0,1] and improve the classical results in some particular cases. Some approximation properties of the new operators in terms of first and second modulus of continuity and the Ditzian‐Totik modulus of smoothness are studied. Quantitative Voronovskaja–type theorems and Grüss‐Voronovskaja–type theorems constitute a great deal of interest of the present work. Some numerical results that compare the rate of convergence of these operators with the classical ones and illustrate the relevance of the theoretical results are given. 相似文献
344.
Ambrožič G Škapin SD Žigon M Crnjak Orel Z 《Journal of colloid and interface science》2011,360(2):370-376
We present a simple, low-temperature synthesis of pure ZnO nanoparticles and polymer-ZnO hybrid materials formed by the NaOH-mediated conversion of poly(zinc dimethacrylate) in 1-butanol. The polymer poly(zinc dimethacrylate) was used as a precursor to prepare neat ZnO particles. It has a double role in the ZnO formation process, acting as a template and simultaneously controlling the crystal growth. The obtained single-crystalline ZnO nanorods show a low tendency to aggregate. The reaction mechanism of ZnO formation was proposed on the basis of a model system of the base-mediated conversion of a monomer zinc dimethacrylate Zn(MA)(2). 相似文献
345.
A novel partial silicon on insulator high voltage LDMOS with low-k dielectric buried layer
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A novel partial silicon-on-insulator (PSOI) high voltage device with a low-k (relative permittivity) dielectric buried layer (LK PSOI) and its breakdown mechanism are presented and investigated by MEDICI.At a low k value the electric field strength in the dielectric buried layer (E I) is enhanced and a Si window makes the substrate share the vertical drop,resulting in a high vertical breakdown voltage;in the lateral direction,a high electric field peak is introduced at the Si window,which modulates the electric field distribution in the SOI layer;consequently,a high breakdown voltage (BV) is obtained.The values of EI and BV of LK PSOI with kI=2 on a 2 μm thick SOI layer over 1 μm thick buried layer are enhanced by 74% and 19%,respectively,compared with those of the conventional PSOI.Furthermore,the Si window also alleviates the self-heating effect. 相似文献
346.
Anton Ramšak Tilen Čadež Ambrož Kregar Lara Ulčakar 《The European physical journal. Special topics》2018,227(3-4):353-363
We consider exactly solvable manipulation of spin-qubits confined in a moving harmonic trap and in the presence of the time dependent Rashba interaction. Non-adiabatic Anandan phase for cyclic time evolution is compared to the Wilczek-Zee adiabatic counterpart. It is shown that the ratio of these two phases can for a chosen system be any real number. Next we demonstrate the possibility of arbitrary qubit transformation in a ring with spin-orbit interaction. Finally, we present an example of exact analysis of spin-orbit dynamics influenced by the Ornstein-Uhlenbeck coloured noise. 相似文献
347.
Florin Diacu Juan Manuel Sánchez-Cerritos Shuqiang Zhu 《Journal of Dynamics and Differential Equations》2018,30(1):209-225
We prove that the fixed points of the curved 3-body problem and their associated relative equilibria are Lyapunov stable if the solutions are restricted to \({\mathbb {S}}^1\), but unstable if the bodies are considered in \({\mathbb {S}}^2\). 相似文献
348.