There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Statistical physics has proven to be a fruitful framework to describe phenomena outside the realm of traditional physics. Recent years have witnessed an attempt by physicists to study collective phenomena emerging from the interactions of individuals as elementary units in social structures. A wide list of topics are reviewed ranging from opinion and cultural and language dynamics to crowd behavior, hierarchy formation, human dynamics, and social spreading. The connections between these problems and other, more traditional, topics of statistical physics are highlighted. Comparison of model results with empirical data from social systems are also emphasized.

Statistical physics of social dynamics

N G van Kampen 1981 Amsterdam: North-Holland xiv + 419 pp price Dfl 180 This is a book which, at a lower price, could be expected to become an essential part of the library of every physical scientist concerned with problems involving fluctuations and stochastic processes, as well as those who just enjoy a beautifully written book. It provides an extensive graduate-level introduction which is clear, cautious, interesting and readable.

https://iopscience.iop.org/article/10.1088/0031-9112/34/4/040/pdf

Stochastic Processes in Physics and Chemistry

From the Publisher: 
The accessible presentation of this book gives both a general view of the entire computer vision enterprise and also offers sufficient detail to be able to build useful applications. Users learn techniques that have proven to be useful by first-hand experience and a wide range of mathematical methods. A CD-ROM with every copy of the text contains source code for programming practice, color images, and illustrative movies. Comprehensive and up-to-date, this book includes essential topics that either reflect practical significance or are of theoretical importance. Topics are discussed in substantial and increasing depth. Application surveys describe numerous important application areas such as image based rendering and digital libraries. Many important algorithms broken down and illustrated in pseudo code. Appropriate for use by engineers as a comprehensive reference to the computer vision enterprise.

Computer vision : a modern approach = 计算机视觉 : 一种现代的方法

We investigate the thermodynamics of a one-dimensional Hubbard model with bond-charge interaction X using the transfer-matrix renormalization-group method Numerical results for various quantities such as spin and charge susceptibilities, particle densities, specific heat, and thermal correlation lengths are presented and discussed We compare our data also to results for the exactly solvable case $X/t=1$ as well as to bosonization results for weak coupling $X/t\ensuremath{\ll}1,$ which shows excellent agreement We confirm the existence of a Tomonaga-Luttinger and a Luther-Emery liquid phase, in agreement with previous studies at zero temperature Thermal singlet-pair-correlation lengths are shown to dominate density and spin correlations for finite temperatures in certain parameter regimes

https://arxiv.org/pdf/cond-mat/0402679.pdf

Thermodynamic properties and thermal correlation lengths of a Hubbard model with bond-charge interaction

We propose a microscopic stochastic model to describe 1D pedestrian trajectories obtained in laboratory experiments. The model is based on optimal velocity (OV) functions and an additive noise determined by the inertial Ornstein-Uhlenbeck process. After statistical estimation of the OV function and noise parameters, we explore the model by simulation. The results show that the stochastic approach gives a good description of the characteristic relation between speed and spacing (fundamental diagram) and its variability. Moreover, it can reproduce the observed stop-and-go waves, bimodal speed distributions, and nonzero speed or spacing autocorrelations.

A stochastic optimal velocity model for pedestrian flow

Recently, Huang and Lin suggested a combination of two successfull mean-field theories, the 2-cluster approximation and paradisical mean-field, for the Nagel-Schreckenberg cellular automaton model of traffic flow. We argue that this new approximation is inconsistent since it violates the Kolmogorov conditions.

Comment on `Garden of Eden states in traffic model revisited'

We present an analysis of traffic data of the highway network of North-Rhine-Westphalia in order to identify and characterize the sections of the network which limit the performance, i.e., the bottlenecks. It is clarified whether the bottlenecks are of topological nature or if they are constituted by on-ramps. This allows to judge possible optimization mechanisms and reveals in which areas of the network they have to be applied. Our results support previous empirical observations and theoretical studies indicating that the overall travel-time of vehicles in a traffic network can be optimized by means of ramp metering control systems.

/pdf/optimization-potential-of-a-highway-network-an-empirical-4ryp9n0qu0.pdf

Optimization Potential of a Highway Network: An Empirical Study

"Conflicts" occur generically in particle-hopping models with parallel dynamics when multiple occupation of sites is forbidden. For cellular automata models of pedestrian dynamics we argue that such conflicts represent an important aspect of the real dynamics. Clogging at bottlenecks is described more realistically if one introduces "friction", i.e. conflicts in which none of the involved agents is allowed to move.

Andreas Schadschneider

Papers

Thermodynamic properties and thermal correlation lengths of a Hubbard model with bond-charge interaction

A stochastic optimal velocity model for pedestrian flow

Comment on `Garden of Eden states in traffic model revisited'

Optimization Potential of a Highway Network: An Empirical Study

Conflicts and Friction in Pedestrian Dynamics