Observation of sub-Doppler absorption in the /Lambda-type three-level Doppler-broadened cesium system

Thanks to the atomic coherence in coupling laser driven atomic system, sub-Doppler absorption has been observed in Doppler-broadened cesium vapor cell via the /Lambda-type three-level scheme. The linewidth of the sub-Doppler absorption peak become narrower while the frequency detuning of coupling laser increases. The results are in agreement with the theoretical prediction by G. Vemuri et al.[PRA,Vol.53(1996) p.2842].Comment: 12 pages, 5 figures, to appear on Applied Physics

Changes of Carbon Emission in Chinese Regional Economy: A Decomposition Analysis Using Nested Logarithmic Mean Divisia Approach

This paper describes a nested logarithmic mean Divisia approach and analyzes the potential factors influencing the changes in carbon emission in Chinese northwest region for the period 1995-2010. The analysis is performed by decomposing annual carbon emission into components representing changes in economic activity, economic structure, energy mix, and energy intensity, population growth, population structure, as well as changes in per capita energy consumption and emission factor. This paper argues that the vast majority of changes in carbon emissions since 1995 are due to economic activity and energy intensity, where the former is found to be a predominant role in rising carbon emission and the later contributing dominantly to decreasing carbon emission. Moreover, the economic structure, population growth, and population structure effects are all found responsible for carbon emissions in the region, although their effects reverse in different time period. Besides, the decreases in carbon emission, however, are attributable mainly to per capita energy consumption and energy mix. There is no doubt that the current emission profile poses significant challenges to the local government’s policies for emission reduction. It is of vital importance to take into account the regional and stage characteristics of influences on carbon emission for policy making

Local multiscale model reduction using discontinuous Galerkin coupling for elasticity problems

In this paper, we consider the constrained energy minimizing generalized multiscale finite element method (CEM-GMsFEM) with discontinuous Galerkin (DG) coupling for the linear elasticity equations in highly heterogeneous and high contrast media. We will introduce the construction of a DG version of the CEM-GMsFEM, such as auxiliary basis functions and offline basis functions. The DG version of the method offers some advantages such as flexibility in coarse grid construction and sparsity of resulting discrete systems. Moreover, to our best knowledge, this is the first time where the proof of the convergence of the CEM-GMsFEM in the DG form is given. Some numerical examples will be presented to illustrate the performance of the method

An MPCC Formulation and Its Smooth Solution Algorithm for Continuous Network Design Problem

Continuous network design problem (CNDP) is searching for a transportation network configuration to minimize the sum of the total system travel time and the investment cost of link capacity expansions by considering that the travellers follow a traditional Wardrop user equilibrium (UE) to choose their routes. In this paper, the CNDP model can be formulated as mathematical programs with complementarity constraints (MPCC) by describing UE as a non-linear complementarity problem (NCP). To address the difficulty resulting from complementarity constraints in MPCC, they are substituted by the Fischer-Burmeister (FB) function, which can be smoothed by the introduction of the smoothing parameter. Therefore, the MPCC can be transformed into a well-behaved non-linear program (NLP) by replacing the complementarity constraints with a smooth equation. Consequently, the solver such as LINDOGLOBAL in GAMS can be used to solve the smooth approximate NLP to obtain the solution to MPCC for modelling CNDP. The numerical experiments on the example from the literature demonstrate that the proposed algorithm is feasible.</p