Plato's Housing Policy: Then and Now

Plato put housing second only to a secure food supply in the order of business of an emerging polis [Republic 2.369d); we argue, without quibbling over rank, that adequate housing ought to have fundamental priority, with health and education, in civil societies' planning, budgets, and legislative agendas. Something made explicit in the Platonic Laws, and often reiterated by today's poor — but as often forgotten by bureaucrats— is that human wellbeing, eudaimonia, is impossible for the homeless. That is, adequate housing is valuable to human societies independently of its instrumental role in supporting the safety, health, and education of the populace. Currently, governments all too frequently end up undermining their own health and education programs as a direct result of neglecting the housing needs of the poor. Finally, we argue that governments ought now to be using the low-cost ways that already exist to provide, or to promote the provision of, better housing for their increasingly urbanized populations; further, even in those circumstances where it is necessary to subsidize housing, governments' most important role is to develop just regulatory and enforcement systems within which public- and private-sector investment can operate

The detection of the electric field vertical distribution underneath thundercloud: Principle and applications

During the Florida 89 experiment at Kennedy Space Center, a new system was used in order to obtain the vertical distribution of the electric field underneath thunderstorms. It consists of a standard shutter field mill at ground level and five other field sensors suspended from a cable fastened to a tethered balloon located at an altitude of about 1000 meters. It also includes a reception station for telemetered information transmitted by sensors, a processing system in order to store data, and real time display on a screen to show the simultaneous field variations at each level along with the instantaneous electric field profile. The first results obtained show the great importance of the electric field vertical distribution. The field detected at a height of 600m reaches 65 kV/m while that at the surface does not exceed 5 kV/m. The field intensity in altitude is a better criterion for determining the right moment to launch a rocket devoted to flash triggering. Using Gauss's law, the simultaneous field variations at several levels are used in order to evaluate charge densities. Average values close to 1nC.m(-3) are calculated in layers up to 600 m. The calculation of different average charge densities leads to the characterization of the layer between cloud and ground just before the leader propagation in the case of cloud to ground flash

Stochastic dynamics of a finite-size spiking neural network

We present a simple Markov model of spiking neural dynamics that can be analytically solved to characterize the stochastic dynamics of a finite-size spiking neural network. We give closed-form estimates for the equilibrium distribution, mean rate, variance and autocorrelation function of the network activity. The model is applicable to any network where the probability of firing of a neuron in the network only depends on the number of neurons that fired in a previous temporal epoch. Networks with statistically homogeneous connectivity and membrane and synaptic time constants that are not excessively long could satisfy these conditions. Our model completely accounts for the size of the network and correlations in the firing activity. It also allows us to examine how the network dynamics can deviate from mean-field theory. We show that the model and solutions are applicable to spiking neural networks in biophysically plausible parameter regimes

Spontaneous Dynamics of Asymmetric Random Recurrent Spiking Neural Networks

We study in this paper the effect of an unique initial stimulation on random recurrent networks of leaky integrate and fire neurons. Indeed given a stochastic connectivity this so-called spontaneous mode exhibits various non trivial dynamics. This study brings forward a mathematical formalism that allows us to examine the variability of the afterward dynamics according to the parameters of the weight distribution. Provided independence hypothesis (e.g. in the case of very large networks) we are able to compute the average number of neurons that fire at a given time -- the spiking activity. In accordance with numerical simulations, we prove that this spiking activity reaches a steady-state, we characterize this steady-state and explore the transients.Comment: 28 pages, 7 figure

Des dieux dans la ville : le paganisme "thérapeutique" de Jacques Réda

National audiencePour Réda, homme "qui a trop pris le large", la religion païenne intervient dans le contexte d'une relation ambivalente avec le christianisme. Le Dieu chrétien, absent ou désintéressé, n'est plus un recours possible pour celui qui garde une certaine aspiration mystique et spirituelle, dans un siècle qui confirme la "mort de Dieu". Mais le paganisme rédien n'est pas seulement négatif : les dieux se présentent en fait comme une sorte de pharmacopée ("du gardénal et de l'asprine", selon ses mots) apte à apaiser sinon à guérir un rapport contrarié à l'espace. Chacun des dieux se conçoit alors comme un "mode" d'apparition des éléments perçus, fondant une ontologie instinctive et toujours ironique. Plus fondamentalement peut-être, le recours à l'imaginaire et aux figures païennes intervient comme un ressourcement qui trouve dans la naïveté de l'enfant le modèle d'un rapport heureux à l'espace

Des dieux dans la ville : le paganisme "thérapeutique" de Jacques Réda

National audiencePour Réda, homme "qui a trop pris le large", la religion païenne intervient dans le contexte d'une relation ambivalente avec le christianisme. Le Dieu chrétien, absent ou désintéressé, n'est plus un recours possible pour celui qui garde une certaine aspiration mystique et spirituelle, dans un siècle qui confirme la "mort de Dieu". Mais le paganisme rédien n'est pas seulement négatif : les dieux se présentent en fait comme une sorte de pharmacopée ("du gardénal et de l'asprine", selon ses mots) apte à apaiser sinon à guérir un rapport contrarié à l'espace. Chacun des dieux se conçoit alors comme un "mode" d'apparition des éléments perçus, fondant une ontologie instinctive et toujours ironique. Plus fondamentalement peut-être, le recours à l'imaginaire et aux figures païennes intervient comme un ressourcement qui trouve dans la naïveté de l'enfant le modèle d'un rapport heureux à l'espace