Exploring travellers’ risk preferences with regard to travel time reliability on the basis of GPS trip records

Travel time reliability has attracted considerable interest in the field of route choice modelling. Knowing how individuals choose paths with uncertain travel times is fundamental to advancing our understanding of route choice behaviour and thus driving the development of route guidance systems. In general, existing navigation systems provide the shortest path on the basis of distance or travel time, even though many travellers do not intend to choose the shortest path. Several studies have shown that the probability of delay or travel time reliability is an important factor in a traveller’s route choice decision. Learning a traveller’s risk preference with regard to travel time reliability is important for designing a preferable route. Traditionally, route choice data for individual preference analysis are collected by conducting stated preference surveys. However, this approach is difficult to avoid its inherent limitation, namely a lack of honest, accurate, and bias-free reporting. To overcome these problems, the present study proposes a new data collection methodology that facilitates estimation of a traveller’s risk preference on the basis of large-scale GPS trip records. The lower and upper bounds of individual risk preference can be estimated by exhausting a series of reliable paths with different on-time arrival probabilities and using the theory of stochastic dominance. Then, a regression model based on a logistic function is established to explore how socio-demographic and trip characteristics influence the lower and upper bounds. Thus, individual properties, such as age, and pre-trip information, such origindestination (OD) distance, departure time, and day of week, are found to have a significant influence on the degree of risk preference

Forecasting intercity rail ridership using revealed preference and stated preference data

The aims of this paper i) to present a methodology for incorporating revealed preference (RP) and stated preference (SP) data in discrete choice models，ii) to apply the methodology to intercity travel mode choice analysis，and iii) to predict new mode shares for each O-D pair resulting from changes in service levels. The combined estimation technique with RP and SP data is developed to promote advantages of the two complementary data sources. The empirical study of intercity travel demand demonstrates the practicality of the methodology by accurately reproducing observed aggregate data and by applying a flexible operational prediction method

Mobility Styles and Affinity for Public Transport Services in Romanian Urban Areas

Attitudes and perceptions expressed by respondents in questionnaire surveys play an important role in creating informed policy decisions. Under a complex environment policy, within the European Union, that is aimed at tackling urban mobility challenges, member states such as Romania have recently been transposing and assimilating Sustainable Urban Mobility Plans into urban development regulations. The legacy of business-as-usual approaches are still dominating urban transport interventions, mainly addressing level-of-service for private motorized transport, while measures dedicated to public and active transport are either lacking consistency or are being delayed for years. With shallow and hastened public consultation procedures, and little consideration for the role of attitudes and perceptions in urban transport quality assessment, this paper aims at providing local administrations with exploratory tools to understand and segment the mobility styles of their citizens. The data used in this article is based on a research-based mobility survey in Cluj-Napoca, Romania, and the results will help decision-makers understand travel behavior and provide them with alternative information in shaping urban transport policy decisions.publishedVersio

<ORIGINAL REPORT>IMMUNOHISTOCHEMICAL STUDIES ON LACTATE DEHYDROGENASE SUBUNITS IN LUNG CANCER CELLS

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。Immunohistochemical distribution of lactate dehydrogenase (LDH) subunits in human lung cancer cells were studied using fluorescent antibody technique. Both in cytological and histological specimen, specific fluorescence of LDH-H and LDH-M were seen in the cytoplasm of cancer cells, and in most cases no remarkable difference could be demonstrated between the distribution of H and M subunit. But in some cases specific fluorescence of M-subunit was stronger than that of H-subunit. The fluorescence of M-subunit was demonstrated as fine granules diffusely in the cytoplasm. On the other hand the fluorescence of H-subunit was rather localized and demonstrated as rather coarse granules. And this observation was discussed

Statistical Mechanics of Self--Gravitating System : Cluster Expansion Method

We study statistical mechanics of the self--gravitating system applying the cluster expansion method developed in solid state physics. By summing infinite series of diagrams, we derive a complex free energy whose imaginary part is related to the relaxation time of the system. Summation of another series yields two--point correlation function whose correlation length is essentially given by the Jeans wavelength of the system.Comment: 4 pages including 2 eps figures, RevTe

Origin of scaling structure and non-gaussian velocity distribution in self-gravitating ring model

Fractal structures and non-Gaussian velocity distributions are characteristic properties commonly observed in virialized self-gravitating systems such as galaxies or interstellar molecular clouds. We study the origin of these properties using the one-dimensional ring model which we newly propose in this paper. In this simple model, $N$ particles are moving, on a circular ring fixed in the three dimensional space, with mutual interaction of gravity. This model is suitable for accurate symplectic integration method by which we find the phase transition in this system from extended-phase to collapsed-phase through an interesting phase (\halo-phase) which has negative specific heat. In this intermediate energy scale, there appear scaling properties, non-thermal and non-Gaussian velocity distributions. In contrast, these peculiar properties are never observed in other \gas and \core phases. Particles in each phase have typical time scales of motion determined by the cutoff length $\xi$, the ring radius $R$ and the total energy $E$. Thus all relaxation patterns of the system are determined by these three time scales.Comment: 21pages,11figure

Carbon monoxide: impact on remethylation/transsulfuration metabolism and its pathophysiologic implications

Carbon monoxide (CO) is a gaseous product generated by heme oxygenase (HO), which oxidatively degrades heme. While the stress-inducible HO-1 has well been recognized as an anti-oxidative defense mechanism under stress conditions, recent studies suggest that cancer cells utilize the reaction for their survival. HO-2, the constitutive isozyme, also plays protective roles as a tonic regulator for neurovascular function. Although protective roles of the enzyme reaction and CO have extensively been studied, little information is available on the molecular mechanisms by which the gas exerts its biological actions. Recent studies using metabolomics revealed that CO inhibits cystathionine β-synthase (CBS), which generates H2S, another gaseous mediator. The CO-dependent CBS inhibition may impact on the remethylation cycle and related metabolic pathways including the methionine salvage pathway and polyamine synthesis. This review focuses on the gas-responsive regulation of metabolic systems, particularly the remethylation and transsulfuration pathways, and their putative implications for cancer and ischemic diseases

Universal Non-Gaussian Velocity Distribution in Violent Gravitational Processes

We study the velocity distribution in spherical collapses and cluster-pair collisions by use of N-body simulations. Reflecting the violent gravitational processes, the velocity distribution of the resultant quasi-stationary state generally becomes non-Gaussian. Through the strong mixing of the violent process, there appears a universal non-Gaussian velocity distribution, which is a democratic (equal-weighted) superposition of many Gaussian distributions (DT distribution). This is deeply related with the local virial equilibrium and the linear mass-temperature relation which characterize the system. We show the robustness of this distribution function against various initial conditions which leads to the violent gravitational process. The DT distribution has a positive correlation with the energy fluctuation of the system. On the other hand, the coherent motion such as the radial motion in the spherical collapse and the rotation with the angular momentum suppress the appearance of the DT distribution.Comment: 11 pages, 19 eps figures, RevTex, submitted to PRE, Revised version, minor change

ELECTROPORATION OF BOVINE BLASTOCYSTS

The introduction of exogenous molecules into embryos is required for analyses of molecular dynamics and specific gene functions during early embryonic development. Electroporation is an effective method to transport exogenous molecules into cells, but is rarely used in bovine embryos. First, we evaluated the viability of in vivo-derived bovine blastocysts after electroporation with fluorescein (FAM) labeled-oligonucleotides with varying pulse numbers (3, 5, 7, and 10), while keeping the pulse duration at 1 msec and the electric field of 20 V/mm. Next, we examined the effects of zona pellucida status on blastocyst quality after electroporation, by comparing the average diameter of blastocysts before and after electroporation using blastocysts with intact zona pellucida and hatching/hatched blastocysts. Electroporation successfully introduced exogenous molecules into in vivo-derived bovine blastocysts without loss of viability. Moreover, the status of the zona pellucida may be associated with the quality of blastocysts after electroporation