578 research outputs found
Public pension and household saving: Evidence from China
We relate household saving to pension reform, to explain the high household saving rates in urban China from a new perspective. We use the exogenous – policy induced - variation in pension wealth to explicitly estimate the impact of pension wealth on household saving, and obtain a significant offset effect of pension wealth on household saving. Our estima-tions show that pension reform boosted the household saving rate in 1999 by about 6 per-centage points for cohort aged 25-29 and by about 3 percentage points for cohort aged 50-59. Our results also indicate that declining pension wealth reduces expenditure on educa-tion and health more than on other consumption items.pensions; pension reform; household savings rate; China
An Overview of Theoretical Researches on Science Communication and Popularization in China
This paper discusses the development of theoretical researches on Science Communication and Popularization (SCP) in China. The article claims that the research on SCP is continuously expanding. The theoretical research looks into interdisciplinary communication and integration, the disseminators and audiences, new media and modes of SCP. The paper concludes that theoretical research becomes further systematic adapting to social development and technological progress of China
Quantifying AS Path Inflation by Routing Policies
A route in the Internet may take a longer AS path than the shortest AS path due to routing policies. In this paper, we systematically analyze AS paths and quantify the extent to which routing policies inflate AS paths. The results show that AS path inflation in the Internet is more prevalent than expected. We first present the extent of AS path inflation observed from the RouteView and RIPE routing tables. We then employ three common routing policies to show the extent of AS path inflation. We find that No-Valley routing policy causes the least AS path inflation among the three routing policies. PreferCustomer-and-Peer-over-Provider policy causes the most AS path inflation. In addition, we find that single-homed stub ASes experience more path inflations than transit ASes and multi-homed ASes. The AS pairs with shortest AS path of 3 AS hops experience more path inflations than other AS pairs. Finally, we investigate the AS path inflation on the end-to-end path from end users to two popular content providers, Google and Comcast. Although the majority of the shortest AS paths from end users to the two providers consists of no more than three AS hops, the actual end-to-end paths that the traffic will take are longer than the shortest AS paths in many cases. Quantifying AS path inflation in the Internet has important implications on the extent of routing policies, traffic engineering performed on the Internet, and BGP convergence speed
Electronic structure of self-assembled InAs/InP quantum dots: A Comparison with self-assembled InAs/GaAs quantum dots
We investigate the electronic structure of the InAs/InP quantum dots using an
atomistic pseudopotential method and compare them to those of the InAs/GaAs
QDs. We show that even though the InAs/InP and InAs/GaAs dots have the same dot
material, their electronic structure differ significantly in certain aspects,
especially for holes: (i) The hole levels have a much larger energy spacing in
the InAs/InP dots than in the InAs/GaAs dots of corresponding size. (ii)
Furthermore, in contrast with the InAs/GaAs dots, where the sizeable hole ,
intra-shell level splitting smashes the energy level shell structure, the
InAs/InP QDs have a well defined energy level shell structure with small ,
level splitting, for holes. (iii) The fundamental exciton energies of the
InAs/InP dots are calculated to be around 0.8 eV ( 1.55 m), about
200 meV lower than those of typical InAs/GaAs QDs, mainly due to the smaller
lattice mismatch in the InAs/InP dots. (iii) The widths of the exciton
shell and shell are much narrower in the InAs/InP dots than in the
InAs/GaAs dots. (iv) The InAs/GaAs and InAs/InP dots have a reversed light
polarization anisotropy along the [100] and [10] directions
Unusual Compression Behavior of Columbite TiO2 via First-Principles Calculations
The physical mechanisms behind the reduction of the bulk modulus of a
high-pressure cubic TiO2 phase are confirmed by first-principles calculations.
An unusual and abrupt change occurs in the dependence of energy on pressure at
43 GPa, indicating a pressure-induced phase transition from columbite TiO2 to a
newly-identified modified fluorite TiO2 with a Pca21 symmetry. Oxygen atom
displacement in Pca21 TiO2 unexpectedly reduces the bulk modulus by 34%
relative to fluorite TiO2. This discovering provides a direct evidence for
understanding the compressive properties of such groups of homologous materialsComment: [email protected] or [email protected]
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