Spatial Resolution of a Micromegas-TPC Using the Charge Dispersion Signal

The Time Projection Chamber (TPC) for the International Linear Collider will need to measure about 200 track points with a resolution close to 100 $\mu$m. A Micro Pattern Gas Detector (MPGD) readout TPC could achieve the desired resolution with existing techniques using sub-millimeter width pads at the expense of a large increase in the detector cost and complexity. We have recently applied a new MPGD readout concept of charge dispersion to a prototype GEM-TPC and demonstrated the feasibility of achieving good resolution with pads similar in width to the ones used for the proportional wire TPC. The charge dispersion studies were repeated with a Micromegas TPC amplification stage. We present here our first results on the Micromegas-TPC resolution with charge dispersion. The TPC resolution with the Micromegas readout is compared to our earlier GEM results and to the resolution expected from electron statistics and transverse diffusion in a gaseous TPC.Comment: 5 pages, 8 figures, to appar in the Proceedings of the 2005 International Linear Collider Workshop (LCWS05), Stanford, 18-22 March 200

Horizon Pretracking

We introduce horizon pretracking as a method for analysing numerically generated spacetimes of merging black holes. Pretracking consists of following certain modified constant expansion surfaces during a simulation before a common apparent horizon has formed. The tracked surfaces exist at all times, and are defined so as to include the common apparent horizon if it exists. The method provides a way for finding this common apparent horizon in an efficient and reliable manner at the earliest possible time. We can distinguish inner and outer horizons by examining the distortion of the surface. Properties of the pretracking surface such as its expansion, location, shape, area, and angular momentum can also be used to predict when a common apparent horizon will appear, and its characteristics. The latter could also be used to feed back into the simulation by adapting e.g. boundary or gauge conditions even before the common apparent horizon has formed.Comment: 14 pages, 8 figures, minor change

The Impact of International Trade on Labour Markets. The Case of Outward Processing Traffic between the European Union and Central Eastern European Countries

In this paper we are trying to evaluate the differential impact of Outward Processing Traffic (OPT) flows with respect to the final trade flows on the labour markets of EU countries. In particular, two EU countries are investigated, Germany and Italy, because of their relevance on total EU-CEEC OPT flows and because they embody two different models of outsourcing towards CEECs. The factor content of trade (FCT) analysis conducted at both levels of inter-industry trade and intra-industry trade signals a more relevant impact of OPT flows than final flows. In particular, results suggest that the labour market effects of intra-industry trade flows deriving from the vertical disintegration of production add significantly to the estimated factor market impact of trade.intra-industry trade; EU-CEEC trade; vertical disintegration; quality differentiation; labour market effects of international trade

Uncertainty modelling in power system state estimation

A method for uncertainty analysis in power system state estimation is proposed. The two-step method uses static weighted least-squares analysis to compute 'point' state estimates. Linear programming is then employed to obtain the upper and lower bounds of the uncertainty interval. It is shown that the method can provide useful additional information for both metered and nonmetered elements of the system. The effects of network parameter errors are also studied. For illustrative purposed, the proposed method is tested using the six-bus and IEEE 30-bus standard systems. Results show that the proposed method is an accurate and reliable tool for estimating the uncertainty bounds in power system state estimation

Bas-en-Basset – Le Clémensoux

Identifiant de l'opération archéologique : 2006/211 et 267 Date de l'opération : 2006 (EX) La parcelle traitée se situe sur la rive droite de la Loire à environ 150 m du fleuve et à une vingtaine de mètres au-dessus du lit majeur lit. Les résultats du diagnostic sont négatifs. Les terrains sondés sont en prairie. La surface totale a été sondée à 6,7 % au moyen de sept tranchées. Celles-ci montrent la présence d’une terrasse alluviale ancienne, présente sous la forme de graves compactes, appar..

Generic Tracking of Multiple Apparent Horizons with Level Flow

We report the development of the first apparent horizon locator capable of finding multiple apparent horizons in a ``generic'' numerical black hole spacetime. We use a level-flow method which, starting from a single arbitrary initial trial surface, can undergo topology changes as it flows towards disjoint apparent horizons if they are present. The level flow method has two advantages: 1) The solution is independent of changes in the initial guess and 2) The solution can have multiple components. We illustrate our method of locating apparent horizons by tracking horizon components in a short Kerr-Schild binary black hole grazing collision.Comment: 13 pages including figures, submitted to Phys Rev

Universal Behavior of Extreme Price Movements in Stock Markets

Many studies assume stock prices follow a random process known as geometric Brownian motion. Although approximately correct, this model fails to explain the frequent occurrence of extreme price movements, such as stock market crashes. Using a large collection of data from three different stock markets, we present evidence that a modification to the random model -- adding a slow, but significant, fluctuation to the standard deviation of the process -- accurately explains the probability of different-sized price changes, including the relative high frequency of extreme movements. Furthermore, we show that this process is similar across stocks so that their price fluctuations can be characterized by a single curve. Because the behavior of price fluctuations is rooted in the characteristics of volatility, we expect our results to bring increased interest to stochastic volatility models, and especially to those that can produce the properties of volatility reported here.Comment: 4 pages, 3 figure