A weakness in strong localization for Sinai's walk

Sinai's walk is a recurrent one-dimensional nearest-neighbor random walk in random environment. It is known for a phenomenon of strong localization, namely, the walk spends almost all time at or near the bottom of deep valleys of the potential. Our main result shows a weakness of this localization phenomenon: with probability one, the zones where the walk stays for the most time can be far away from the sites where the walk spends the most time. In particular, this gives a negative answer to a problem of Erd\H{o}s and R\'{e}v\'{e}sz [Mathematical Structures--Computational Mathematics--Mathematical Modelling 2 (1984) 152--157], originally formulated for the usual homogeneous random walk.Comment: Published at http://dx.doi.org/10.1214/009117906000000863 in the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org

Aging and quenched localization for one-dimensional random walks in random environment in the sub-ballistic regime

We consider transient one-dimensional random walks in random environment with zero asymptotic speed. An aging phenomenon involving the generalized Arcsine law is proved using the localization of the walk at the foot of "valleys" of height $\log t$. In the quenched setting, we also sharply estimate the distribution of the walk at time $t$.Comment: 24 pages, accepted for publication in "Bulletin de la SMF

Limit laws for transient random walks in random environment on \z

We consider transient random walks in random environment on \z with zero asymptotic speed. A classical result of Kesten, Kozlov and Spitzer says that the hitting time of the level $n$ converges in law, after a proper normalization, towards a positive stable law, but they do not obtain a description of its parameter. A different proof of this result is presented, that leads to a complete characterization of this stable law. The case of Dirichlet environment turns out to be remarkably explicit.Comment: 31 pages, accepted for publication in "Annales de l'Institut Fourier

A probabilistic representation of constants in Kesten's renewal theorem

The aims of this paper are twofold. Firstly, we derive some probabilistic representation for the constant which appears in the one-dimensional case of Kesten's renewal theorem. Secondly, we estimate the tail of some related random variable which plays an essential role in the description of the stable limit law of one-dimensional transient sub-ballistic random walks in random environment.Comment: 27 page

Scaling limit and aging for directed trap models

We consider one-dimensional directed trap models and suppose that the trapping times are heavy-tailed. We obtain the inverse of a stable subordinator as scaling limit and prove an aging phenomenon expressed in terms of the generalized arcsine law. These results confirm the status of universality described by Ben Arous and \v{C}ern\'y for a large class of graphs.Comment: 16 pages, accepted for publication in "Markov processes and Related Fields

ICTs and Social Movements under Authoritarian Regimes: An Actor-Network Perspective

There has been significant recent interest in the role of information and communication technologies (ICTs) in social movements protesting against authoritarian regimes. Much of the literature on this topic can be framed in terms of dualities: seeing either technology or (less often) society as the cause of impacts characterised as either liberation or repression. This paper seeks to move beyond those dualities by using actor-network theory (ANT) to study the role of ICTs in Iran’s Green Movement; specifically by applying Callon’s moments of translation. This analysis turns the focus from causes or impacts of social movements, to the dynamics of their trajectory. It presents ICTs as an active actor within this social movement of protest; an actor which rapidly made this movement into a global network. Yet ICTs also betrayed the protest. They simultaneously worked for the Iranian regime. And they allowed a shallowness of translation which enabled quick problematisation, interessement and enrolment, but which equally enabled quick de-enrolment, and which undermined the full mobilisation of this social movement and ultimately led to its disintegration. Recognising the limits but also the originality of actor-network theory, the paper ends by suggesting directions for future ANT-based work on ICTs and social movements

Quenched limits for the fluctuations of transient random walks in random environment on Z

We consider transient nearest-neighbor random walks in random environment on Z. For a set of environments whose probability is converging to 1 as time goes to infinity, we describe the fluctuations of the hitting time of a level n, around its mean, in terms of an explicit function of the environment. Moreover, their limiting law is described using a Poisson point process whose intensity is computed. This result can be considered as the quenched analog of the classical result of Kesten, Kozlov and Spitzer [Compositio Math. 30 (1975) 145-168].Comment: Published in at http://dx.doi.org/10.1214/12-AAP867 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org). arXiv admin note: substantial text overlap with arXiv:1004.133

ANALISIS IKONOGRAFI FOTO JURNAISTIK PADA WORLD PRESS PHOTO CONTEST KARYA FOTOGRAFER INDONESIA

Kehadiran fotografi jurnalistik sering dimanfaatkan untuk urusan kemanusiaan (humanity). Sejalan dengan konsep fotografi jurnalistik selalu berkaitan dengan kemanusiaan atau human interest, yang dapat memunculkan perasaan untuk membangkitkan simpati dan empati. Dalam memaknai sebuah foto berita, tidak hanya dilihat dari aspek visual foto tersebut, tetapi juga dari sudut pandang sejarah sejarah dan fakta terkait dari nilai simbolik foto itu sendiri. Fotografi jurnalistik adalah ilustrasi rangkaian peristiwa yang terdapat dalam bentuk foto yang dipadukan dengan teks, pemberitaan berita atau peristiwa penting yang sebagian besar bersifat kontroversial. Ketika kata-kata tidak bisa lagi menggambarkan informasi, biarkan foto berbicara, biarkan gambar mengungkapkan kenyataan. Dalam sebuah foto jurnalistik momen peristiwa merupakan salah satu aspek penting dalam pembuatan karya foto, hal ini dikenal dengan istilah Decisive Moment yang pertama kali diperkenalkan oleh Henri Cartier-Bresson, salah satu pendiri agen foto terkemuka. Disini foto yang akan akan peneliti bahas adalah foto yang dikategorikan kedalam Spot News Photo dan General News Photo. Terkait obyek karya fotografer jurnalistik milik Sholihuddin, Tarmizy Harva dan Joshua Irwandi yang berhasil lolos dalam penghargaan World Press Photo Contest. Hal yang diperoleh setelah melakukan penelitian adalah bahwa fotografi jurnalistik tecipta karena adanya beberapa factor menelatar-belakanginya, momen, background story kejadian dan komposisi