Search results for "Timing"

Nanoseconds Timing System Based on IEEE 1588 FPGA Implementation

2019

Clock synchronization procedures are mandatory in most physical experiments where event fragments are readout by spatially dislocated sensors and must be glued together to reconstruct key parameters (e.g. energy, interaction vertex etc.) of the process under investigation. These distributed data readout topologies rely on an accurate time information available at the frontend, where raw data are acquired and tagged with a precise timestamp prior to data buffering and central data collecting. This makes the network complexity and latency, between frontend and backend electronics, negligible within upper bounds imposed by the frontend data buffer capability. The proposed research work describ…

Order in the chaos? The strange case of accreting millisecond pulsars

2007

We review recent results from the X-ray timing of accreting millisecond pulsars in Low Mass X-ray Binaries. This is the first time a timing analysis is performed on accreting millisecond pulsars, and for the first time we can obtain information on the behavior of a very fast pulsar subject to accretion torques. We find both spin-up and spin-down behaviors, from which, using available models for the accretion torques, we derive information on the mass accretion rate and magnetic field of the neutron star in these systems. We also find that the phase delays behavior as a function of time in these sources is sometimes quite complex and difficult to interpret, since phase shifts, most probably …

Equity Issues in the Spanish Stock Market: Windows of Opportunity, Earnings Management or Market Timing?

2005

We investigate whether the market sentiment and/or the specific operating performance of firms that conducted an equity issue on the Spanish stock market during the period 1993-2000 are related to the long-run stock-return underperformance in the year following the issue of small and medium firms. Our results reveal that equity issues were conducted by large firms just when the market showed optimistic expectations towards large firms in general. This overoptimism towards large issue firms was related to the 1990s technology boom in the case of initial public offerings (IPO), but we detect earnings management by large firms that conducted a seasoned equity offering (SEO). In this context, s…

A Comprehensive Look at the Real-Life Performance of Moving Average Trading Strategies

2015

Despite the enormous current interest in market timing and a series of publications in academic journals, there is still lack of comprehensive research on the evaluation of the profitability of trading rules using methods that are free from the data-snooping bias. In this paper we utilize the longest historical dataset that spans 155 years and extend previous studies on the performance of moving average trading rules in a number of important ways. Among other things, we investigate whether overweighting the recent prices improves the performance of timing rules; whether there is a single optimal lookback period in each trading rule; and how accurately the trading rules identify the bullish …

The 54 days orbital period of AX J1820.5-1434 unveiled by Swift

2013

The hard X-ray survey that Swift-BAT has been performing since late 2004 has provided a considerable database for a large number of sources whose hard X-ray emission was poorly known. We are exploiting the BAT survey archive to improve the temporal and spectral characterization of the Galactic hard-X-ray sources. In this letter we focus on the study of the high mass X-ray binary AX J1820.5-1434. All the data relevant to AX J1820.5-1434 have been extracted from the BAT survey archive and analyzed using a folding technique to search for periodical modulations. A broad-band spectral analysis was also performed complementing the BAT spectrum with the available Swift-XRT and XMM-Newton pointed o…

An alliance timing game under real options in biopharmaceutical industry

2014

Study of the accretion torque during the 2014 outburst of the X-ray pulsar GRO J1744−28

2017

We present the spectral and timing analysis of the X-ray pulsar GRO J1744-28 during its 2014 outburst using data collected with the X-ray satellites Swift, INTEGRAL, Chandra, and XMM-Newton. We derived, by phase-connected timing analysis of the observed pulses, an updated set of the source ephemeris. We were also able to investigate the spin-up of the X-ray pulsar as a consequence of the accretion torque during the outburst. Relating the spin-up rate and the mass accretion rate as $\dot{\nu}\propto\dot{M}^{\beta}$, we fitted the pulse phase delays obtaining a value of $\beta=0.96(3)$. Combining the results from the source spin-up frequency derivative and the flux estimation, we constrained …

Spin up and phase fluctuations in the timing of the accreting millisecond pulsar XTE J1807-294

2007

We performed a timing analysis of the 2003 outburst of the accreting X-ray millisecond pulsar XTE J1807-294 observed by RXTE. Using recently refined orbital parameters we report for the first time a precise estimate of the spin frequency and of the spin frequency derivative. The phase delays of the pulse profile show a strong erratic behavior superposed to what appears as a global spin-up trend. The erratic behavior of the pulse phases is strongly related to rapid variations of the light curve, making it very difficult to fit these phase delays with a simple law. As in previous cases, we have therefore analyzed separately the phase delays of the first harmonic and of the second harmonic of …

Revisiting the Profitability of Market Timing with Moving Averages

2016

In a recent empirical study by Glabadanidis ("Market Timing With Moving Averages" (2015), International Review of Finance, Volume 15, Number 13, Pages 387-425; the paper is also available on the SSRN and has been downloaded more than 7,500 times) the author reports striking evidence of extraordinary good performance of the moving average trading strategy. In this paper we demonstrate that "too good to be true" reported performance of the moving average strategy is due to simulating the trading with look-ahead bias. We perform the simulations without look-ahead bias and report the true performance of the moving average strategy. We find that at best the performance of the moving average stra…

L'interface des parcelles agricoles, un habitat essentiel pour résoudre les compromis entre services et disservices écosystémiques de la flore advent…

2019

National audience; La flore spontanée se développant dans les champs et leur bordures (adventices) contribue à la fourniture de services écosystémiques comme la pollinisation (fourniture de pollen, nectar) ou le contrôle biologique (fourniture de ressources trophiques telles les graines pour des auxiliaires). Elles peuvent également causer des pertes de rendements ce qui amène les agriculteurs à réduire leur présence dans les champs. Ainsi, à l'échelle d'un paysage agricole, la distribution spatiale des adventices est hétérogène, avec des zones d'interface (espace entre la bordure extérieure et le premier rang de semis) abritant une flore plus diverse et abondante, contribuant potentielleme…