Many-neighbour interaction and non-locality in traffic models

The optimal-velocity model, as proposed by Bando et al. [1], shows unrealistic values of the acceleration for various optimal-velocity functions [2,3]. We discuss different approaches of how to correct this problem. Multiple look-ahead (many-neighbour interaction) models are the most promising candidates in reducing accelerations and decelerations to realistic values. We focus on two such models and, in particular, their linear stability and how these affect the vehicle dynamics and wave solutions. As found earlier [4], multiple look-ahead models reproduce many real flow features, and our results further support the necessity of this ansatz. However, the problem of non-locality arises when they are transformed into the corresponding continuum model. We discuss three methods of how to interpret many-neighbour interaction in macroscopic models.Received: 27 March 2004, Published online: 12 July 2004PACS: 45.70.Vn Granular models of complex systems; traffic flow - 89.90. + n Other topics in areas of applied and interdisciplinary physics - 47.50. + d Non-Newtonian fluid flows     

Coupling constants in N-substituted pyridines and their relation with electronegativity

The coupling constants obtained from the complete spectral analysis of series of 1- and 3-substituted pyridine N-imides are related linearly to the electronegativities of the substituent atoms. The main conclusions of the papers by Cox, Castellano and Sun, and Castellano and Kostelnik are substantiated. The inductive effects of the first atoms of the substituents largely determine the coupling between protons in the ring system; delocalisation of π-electrons in the ring produces a much smaller effect.     

Hollow-core waveguide characterization by optically induced particle transport

We introduce a method for optical characterization of hollow-core optical waveguides. Radiation pressure exerted by the waveguide modes on dielectric microspheres is used to analyze salient properties such as propagation loss and waveguide mode profiles. These quantities were measured for quasi-single-mode and multimode propagation in on-chip liquid-filled hollow-core antiresonant reflecting optical waveguides. Excellent agreement with analytical and numerical models is found, demonstrating that optically induced particle transport provides a simple, inexpensive, and nondestructive alternative to other characterization methods.     

First EMC3-EIRENE modelling of JT-60SA edge plasmas with/without resonant magnetic perturbation field

The first EMC3-EIRENE modelling for the JT-60SA edge plasmas with/without the resonant magnetic perturbation field (RMP) was conducted. Both core degradation in the vacuum approximation and strike-point splitting were observed due to the application of the RMP, as in previous studies in other devices. Toroidally averaged divertor heat fluxes with and without the RMP were fitted by using a one-dimensional diffusive model function, showing similar profiles. To extract the modulation components of the divertor heat flux profile, the proper orthogonal decomposition (POD) method was applied. By using the POD outputs, a modulation ratio with respect to the toroidally averaged profile was quantitatively calculated.     

Spectroscopic elucidation of pseudo-base formation from benzo[8,9]quinoliziono[4,5,6,7-fed]phenanthrindyliums

¹³C and ¹H NMR spectra and UV spectra are recorded and assigned for a variety of substituted and hetero derivatives of benzo[8,9]quinolizino[4,5,6,7-fed]phenanthrindyliums. Large specific effects of traces of water on these spectra are traced to pseudo-base formation.     

Planar optofluidic chip for single particle detection, manipulation, and analysis

We present a fully planar integrated optofluidic platform that permits single particle detection, manipulation and analysis on a chip. Liquid-core optical waveguides guide both light and fluids in the same volume. They are integrated with fluidic reservoirs and solid-core optical waveguides to define sub-picoliter excitation volumes and collect the optical signal, resulting in fully planar beam geometries. Single fluorescently labeled liposomes are used to demonstrate the capabilities of the optofluidic chip. Liposome motion is controlled electrically, and fluorescence correlation spectroscopy (FCS) is used to determine concentration and dynamic properties such as diffusion coefficient and velocity. This demonstration of fully planar particle analysis on a semiconductor chip may lead to a new class of planar optofluidics-based instruments.