How does interchange affect passengers' route choices in urban rail transit? - a case study of the Shanghai Metro

Interchange provides more flexibility in route choice, a key travel behaviour in urban rail transit, but its influence is usually simplified. This paper investigates how interchange affects route choice with passenger perception considered. At single-interchange level, perceived interchange time was proposed and modelled under three resolutions to capture passenger perception and its sensitivity. At route level, the influence of interchange was modeled by first comparing eight quantifications of interchange. Mixed logit models with the best interchange proxy were further developed to address the correlation among alternative routes and reveal the potential taste variations among passengers. Results based on Shanghai Metro data showed perceived interchange time, including passenger perception and interchange environment, better represents the influence of interchange in route choice, meanwhile the weights of interchanges on one route rise sequentially and non-linearly. The results can improve route choice prediction in demand modelling and route recommendation in advanced traveller information systems

Cluster dynamical mean-field study of the Hubbard model on a 3D frustrated hyperkagome lattice

We study the Hubbard model on a geometrically-frustrated hyperkagome lattice by a cluster extension of the dynamical mean field theory. We calculate the temperature ($T$) dependences of the specific heat ($C$) and the spin-lattice relaxation time ($T_1$) in correlated metallic region. $C/T$ shows a peak at $T=T_{p1}$ and rapidly decreases as $T->0$. On the other hand, $1/T_1T$ has a peak at a higher temperature $T_{p2}$ than $T_{p1}$, and largely decreases below $T_{p2}$, followed by the Korringa law $1/T_1 propto T$ as $T->0$. Both peak temperatures are suppressed and the peaks become sharper as electron correlation is increased. These behaviors originate from strong renormalization of the energy scales in the peculiar electronic structure in this frustrated system; a pseudo-gap like feature, the van-Hove singularity, and the flat band. The results are discussed in comparison with the experimental data in the hyperkagome material, Na$_4$Ir$_3$O$_8$.Comment: 4 pages, 4 figures, Conference proceedings for Highly Frustrated Magnetism 200

Railway Timetable Optimization for Air-Rail Intermodal Service

Both aviation and high-speed rail are developing rapidly, which promotes the popularity of intermodal services. However, most cooperation only comes from political support. Operational measures should be taken for further improvement. In such circumstance, a model is proposed in this study to improve the quality of services and strengthen the connectivity between two modes by optimizing the railway timetable. The model is set to maximize the connection numbers of two modes. To take journey is "air-rail" or "rail-air" into consideration, we divide passengers into four groups. The original model is linear and can be calculated by commercial solvers. The models were applied on a case China. The results showed that the model is effective, the connection numbers improved by 40.2%

Role of hydrogen bonding in charge-ordered organic conductor α\alpha-(BEDT-TTF)2_2I3_3 probed by 127^{127}I nuclear quadrupole resonance

We present $^{127}$I nuclear quadrupole resonance spectra and nuclear relaxation of $\alpha$-(BEDT-TTF)$_2$I$_3$ that undergoes a charge-ordering transition. Only one of the two I$_3$ anion sites shows a significant differentiation in the electric field gradients across the first-order transition. The charge modulation only in the BEDT-TTF layers can not reproduce; instead, an anion-donor interaction accompanied by hydrogen bonding is necessary. The dominating source for the nuclear relaxation is the local libration of the I$_3$ anions, but an anomalous peak is detected just below the transition, as observed by $^{13}$C NMR.Comment: 10 pages, 5 figures, accepted for publication in Phys. Rev.

LEDs and power consumption of exterior automotive lighting: Implications for gasoline and electric vehicles

This study evaluated the power consumption of traditional and LED-based exterior lighting systems on passenger vehicles, examining nominal consumption as well as realistic consumption based on real-world usage patterns of various lighting equipment. The results indicate that an all-LED system employing the current generation of LEDs would result in general power savings of about 50% (nighttime) to about 75% (daytime) over a traditional system. The effect on long-term savings for the LED system depends upon the type of vehicle in use (gasoline-powered vs. electric). While the long-term fuelcost savings (dollars) were higher for the gasoline-powered vehicle, long-term distance savings (range) favored the electric vehicle. Also presented are calculations of potential savings for two different scenarios of future improvements in LED power consumption.University of Michigan Industry Affiliation Program for Human Factors in Transportation Safetyhttp://deepblue.lib.umich.edu/bitstream/2027.42/61187/1/100985.pd

Nuclear spin-spin coupling in La_{2-x}Sr_{x}CuO_{4} studied by stimulated echo decay

We have performed copper NQR experiments in high temperature superconductors YBa_{2}Cu_{4}O_{8}, YBa_{2}Cu_{3}O_{7}, and La_{2-x}Sr_{x}CuO_{4} (x=0.12 and 0.15), using the stimulated echo technique. The stimulated echo intensity is analyzed by a model that includes the spin-lattice relaxation process (T_ {1 }-process) and the fluctuating local field due to nuclear spin-spin coupling. The model gives quantitative account of the experimental results in Y-based compounds using the known values of 1/T_{1} and 1/T_{2G}, the gaussian decay rate of the spin echo intensity. The same model applied to LSCO enables us to extract the value of T_{2G}. Our results indicate that T_{1}T/T_{2G} is independent of temperature, implying that the dynamic exponent is one in La_{2-x}Sr_{x}CuO_{4}.Comment: 14 pages, 11 fugures, The bibliography field is correcte

Superconductivity in Pr2Ba4Cu7O15-delta with metallic double chains

We report superconductivity with $T_{c,onset}$=$\sim$10K in Pr$_{2}$Ba$_{4}$Cu$_{7}$O$_{15-\delta}$ compound possessing metallic double chains. A reduction treatment on as-sintered samples causes not only the enhanced metallic conduction but also the appearance of superconductivity accompanied by the c-axis elongation due to oxygen deficiency

Application of GGBFS and Bentonite to Auto-Healing Cracks of Cement Paste

Cracks are caused by many factors. Shrinkage and external loading are the most common reason. It becomes a problem when the ingression of aggressive and harmful substance penetrates to the concrete gap. This problem reduces the durability of the structures. It is well known that self – healing of cracks significantly improves the durability of the concrete structure. This paper presents self-healing cracks of cement paste containing bentonite associated with ground granulated blast furnace slag. The self-healing properties were evaluated with four parameters: crack width on the surface, crack depth, tensile strength recovery, and flexural recovery. In combination with microscopic observation, a healing process over time is also performed. The results show that bentonite improves the healing properties, in terms of surface crack width and crack depth. On the other hand, GGBFS could also improve the healing process, in terms of crack depth, direst tensile recovery, and flexural stiffness recovery. Carbonation reaction is believed as the main mechanism, which contributes the self-healing process as well as the continuous hydration progress

Turbulence in Boundary Flow of Superfluid 4^4He Triggered by Free Vortex Rings

The transition to turbulence in the boundary flow of superfluid $^4$He is investigated using a vortex--free vibrating wire. At high wire vibration velocities, we found that stable alternating flow around the wire enters a turbulent phase triggered by free vortex rings. Numerical simulations of vortex dynamics demonstrate that vortex rings can attach to the surface of an oscillating obstacle and expand unstably due to the boundary flow of the superfluid, forming turbulence. Experimental investigations indicate that the turbulent phase continues even after stopping the injection of vortex rings, which is also confirmed by the simulations.Comment: 4 pages, 4 figures, submitted to AP

Mechanism of particle transport in magnetized silane plasmas

Particle transport phenomena were investigated in silane plasmas in the presence of a magnetic field B perpendicular to a discharge electric field E. From the experimental results, it was concluded that silicon particles were transported in the opposite direction to the E × B drift, and the particle density decreased with increasing applied magnetic flux density. Theoretical calculations on particle drift show that negatively charged particles can be transported in the opposite direction to E × B drift and the drift velocity increases with B for the present experimental conditions. Both experimental and theoretical results suggest that transport by modified ambipolar E × B drift can eliminate particles from discharge space