Nonlinear Pricing on Private Roads with Congestion and Toll Collection Costs

Nonlinear pricing (a form of second-degree price discrimination) is widely used in transportation and other industries but it has been largely overlooked in the road-pricing literature. This paper explores the incentives for a profit-maximizing toll-road operator to adopt some simple nonlinear pricing schemes when there is congestion and collecting tolls is costly. Users are assumed to differ in their demands to use the road. Regardless of the severity of congestion, an access fee is always profitable to implement either as part of a two-part tariff or as an alternative to paying a toll. Use of access fees for profit maximization can increase or decrease welfare relative to usage-only pricing. Hence a ban on access fees could reduce welfare.congestion pricing; two-part pricing; private roads; toll collection costs

The electronic instabilities of the Iron-based superconductors: a variational Monte-Carlo study

We report the first variational Monte Carlo (VMC) study of the iron-based superconductors. We use realistic band structures, and the ordering instabilities/variational ansatzs are suggested by previous functional renormalization group calculations. We examine antiferromagnetism, superconducting pairing, normal state fermi surface distortion, and orbital order in the antiferromagnetic state.Comment: Journal reference: Phys. Rev. B 83, 134502 (2011

Design of Compact Planar Diplexer Based on Novel Spiral-Based Resonators

A miniaturized planar diplexer utilizing the novel spiral-based resonators is proposed. The given cell which is initially proposed in this article is composed of two separated rectangular spirals which are asymmetrical to each other and thus, it is called as ‘asymmetrical separated spirals resonator’ (ASSR). ASSR has more superior transmission property than the previous prototype and extremely compact dimension is also achieved. It is demonstrated that ASSR can exhibit bandpass performance with high frequency selectivity and good transmission property within the relatively low frequency band. Based on the given characteristic, one planar diplexer composed of T-junction and two ASSRs is synthesized and the fabricated prototype with compact dimension is achieved, thanks to ASSRs explored. Simultaneously, the transversal dimension of each channel is extremely compact because ASSRs are completely embedded in the feed lines. Both the simulated and measured results indicate that satisfactory impedance matching and high isolation between two channels are achieved. Furthermore, the proposed diplexer is uniplanar and no defected ground structure is introduced