Extract Timing Information Research Articles

Euskarazko denbora-egiturak. Azterketa eta etiketatze-esperimentua

Time information extraction is very useful in natural language processing (NLP), as it can be used in text simplification, information extraction and machine translation systems. In this paper we present the first steps of making that information accessible for Basque language: on one hand, Basque structures that convey time have been analysed based on grammars and, on the other hand, first decisions on tagging those on real texts have been taken. Also, we give account of an annotating experiment we have carried out on a financial news corpus.

Fully digital readout of segmented solid state detectors

In this work, the digital readout of semiconductor detectors in combination with digital filters was investigated. Both non-segmented high-purity germanium and segmented planar lithium-drifted silicon detectors were used. In each case, photons from a stationary americium (241Am) gamma source were detected. The resulting preamplifier output pulses were digitized at a fixed sampling frequency and stored entirely. Digital filters were applied to the stored waveforms to extract time and energy information. The performance of different digital filters was compared. The optimum energy resolution obtained was comparable with the value resulting from an analogue readout system based on standard nuclear instrumentation module and versatile module Europe bus electronics.

In situ irregularity identification and scintillation estimation using wavelets and CINDI on C/NOFS

Wavelets are a time‐domain method that is able to extract both time and frequency information from a signal. The Morlet wavelet is used here to characterize the magnitude of ionospheric irregularities using measurements of the total ion density from the Coupled Ion Neutral Dynamics Investigation package onboard the Communications/Navigation Outage Forecasting System spacecraft. The power in ionospheric irregularities at scale sizes less than 128 km is used to generate an irregularity amplitude index. This index is used with a phase screen analysis to form an estimate of scintillation at the satellite location. The temporal information retained in a wavelet analysis also allows for an accurate power spectrum calculation even when used on short segments of data which is useful for real‐time processing of irregularity detection onboard a satellite or for analyzing the long data sets produced by a satellite. To validate the process, a comparison of the in situ scintillation estimate and Scintillation Network and Decision Aid measurements of the S4 index is presented.

Collaborative opportunistic navigation [Student research highlight

Motivated by the plenitude of ambient radio frequency signals in GNSS-challenged environments, a new paradigm to overcome the limitations of GNSS-based navigation is proposed. This paradigm, termed opportunistic navigation (OpNav), aims to extract positioning and timing information from ambient radio frequency signals of opportunity (SOPs). OpNav radio receivers continuously search for opportune signals from which to draw navigation and timing information, employing on-the-fly signal characterization as necessary. In collaborative opportunistic navigation (COpNav), multiple OpNav receivers share information to construct and continuously refine a global signal landscape.

Hardware‐efficient phase‐detection technique for digital clock and data recovery

A phase-detection technique for digital clock and data recovery (CDR) in multi-Gbit/s serial links is presented. Compared to conventional sampling-based receivers, hardware efficiency at the system-level is achieved by extracting timing information from analysing the occurrence of certain patterns at the output of four comparators. The arrangement of the decision threshold and sampling time of these comparators is discussed, and the phase and frequency detection characteristic of such an arrangement is evaluated. The technique is validated through a proof-of-concept 12.5 Gbit/s CDR chip that is fabricated in 90nm CMOS.

Time-resolved photoemission on the attosecond scale: opportunities and challenges

The interaction of laser pulses of sub-femtosecond duration with matter opened up the opportunity to explore electronic processes on their natural time scale. One central conceptual question posed by the observation of photoemission in real time is whether the ejection of the photoelectron wavepacket occurs instantaneously, or whether the response time to photoabsorption is finite leading to a time delay in photoemission. Recent experimental progress exploring attosecond streaking and RABBIT techniques find relative time delays between the photoemission from different atomic substates to be of the order of -20 attoseconds. We present ab initio simulations for both one- and two-electron systems which allow the determination of both absolute and relative time delays with -1 attosecond precision. We show that the intrinsic time shift of the photoionization process encoded in the Eisenbud-Wigner-Smith delay time can be unambiguously disentangled from measurement-induced time delays in a pump-probe setting when the photoionized electronic wavepacket is probed by a modestly strong infrared streaking field. We identify distinct contributions due to initial-state polarization, Coulomb-laser coupling in the final continuum state as well as final-state interaction with the entangled residual ionic state. Extensions to multi-electron systems and to the extraction of time information in the presence of decohering processes are discussed.

Formal Verification of Architectural Power Intent

This paper presents a verification framework that attempts to bridge the disconnect between high-level properties capturing the architectural power management strategy and the implementation of the power management control logic using low-level per-domain control signals. The novelty of the proposed framework is in demonstrating that the architectural power intent properties developed using high-level artifacts can be automatically translated into properties over low-level control sequences gleaned from UPF specifications of power domains, and that the resulting properties can be used to formally verify the global on-chip power management logic. The proposed translation uses a considerable amount of domain knowledge and is also not purely syntactic, because it requires formal extraction of timing information for the low-level control sequences. We present a tool, called POWER-TRUCTOR which enables the proposed framework, and several test cases of significant complexity to demonstrate the feasibility of the proposed framework.

Design and Implementation of Dual-Channel and Dual-Mode Timing Module Based on Beidou & GPS

Against the Status quo that satellite timing service in many fields of China mainly relies on the GPS system, for full use of the Beidou navigation satellite system with our own intellectual property, this paper presented a chip-level solution of dual-channel and dual-mode timing modules based on the Beidou-2 and GPS navigation system. The timing principle of Beidou navigation satellite system was first introduced, and then the hardware design of the timing module was presented with selection of highly-integrated RF chip and baseband processor chip. Furthermore, many kinds of output interfaces were designed to meet diverse service demand. By analyzing the format of the received signal, the flow chart for extracting timing information was also given. Finally, the designed timing module was tested by using the developed timing display system and test results show that the module has a better timing performance.

FPGA-Based Pulse Pile-Up Correction With Energy and Timing Recovery

Modern field programmable gate arrays (FPGAs) are capable of performing complex discrete signal processing algorithms with clock rates well above 100 MHz. This, combined with FPGA's low expense, ease of use, and selected dedicated hardware make them an ideal technology for a data acquisition system for a positron emission tomography (PET) scanner. The University of Washington is producing a high-resolution, small-animal PET scanner that utilizes FPGAs as the core of the front-end electronics. For this scanner, functions that are typically performed in dedicated circuits, or offline, are being migrated to the FPGA. This will not only simplify the electronics, but the features of modern FPGAs can be utilized to add significant signal processing power to produce higher quality images. In this paper we report on an all-digital pulse pile-up correction algorithm that has been developed for the FPGA. The pile-up mitigation algorithm will allow the scanner to run at higher count rates without incurring large data losses due to the overlapping of scintillation signals. This correction technique utilizes a reference pulse to extract timing and energy information for most pile-up events. Using pulses acquired from a Zecotech Photonics MAPD-N with an LFS-3 scintillator, we show that good timing and energy information can be achieved in the presence of pile-up utilizing a moderate amount of FPGA resources.

Performance of Cooled PWO Scintillators With Signal-Sampling Readout

For the investigation of the charmonium spectrum, yet undiscovered charm-meson states and glueballs, the PANDA detector will be employed at the future FAIR facility. PANDA will contain an electromagnetic calorimeter composed of PbWO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> (PWO) crystals that are cooled to -25 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> C and coupled to large-area avalanche photodiodes or vacuum phototriodes/-tetrodes. The photosensor signals are continuously digitized by sampling analog-to-digital converters (SADCs) and analyzed online in field programmable gate arrays (FPGAs) that are part of the digitizer module to detect hits and extract energy and time information. The online SADC-data processing algorithm was designed, optimized, and implemented in VHDL for a Xilinx FPGA. In order to estimate the performance of the SADC readout of cooled PWO crystals, several measurements with tagged photons in the energy range of 60 MeV-1.4 GeV were performed. The digital readout improves the energy resolution in particular at low photon energies and simultaneously provides a time resolution below 1 ns for an energy deposition above 80 MeV. The successful application of the online data-processing procedure is an essential step toward the development of a trigger-less readout concept of the data acquisition for the PANDA experiment.

The symmetries of image formation by scattering II Applications

We show that the symmetries of image formation by scattering enable graph-theoretic manifold-embedding techniques to extract structural and timing information from simulated and experimental snapshots at extremely low signal. The approach constitutes a physically-based, computationally efficient, and noise-robust route to analyzing the large and varied datasets generated by existing and emerging methods for studying structure and dynamics by scattering. We demonstrate three-dimensional structure recovery from X-ray diffraction and cryo-electron microscope image snapshots of unknown orientation, the latter at 12 times lower dose than currently in use. We also show that ultra-low-signal, random sightings of dynamically evolving systems can be sequenced into high quality movies to reveal their evolution. Our approach offers a route to recovering timing information in time-resolved experiments, and extracting 3D movies from two-dimensional random sightings of dynamic systems.

Role Of Rfid To Minimize Reverse Logistics: A Case Study Perspective

Reverse logistics is considered as a part of supply chain and can be minimized in the form of complaints received to strengthen the whole supply chain. Henceforth this paper attempts to analyze the gaps between identified defects and complaints received in ongoing production process through statistical analysis, which can be utilized further to minimize. A case study from a chemical industry has been considered to reflect this gap. Additionally author has made an attempt to explain the impact and efficacy of RFID for minimizing the reverse logistics part (received complaints) in the form of proposed algorithm. This algorithm may help further to monitor manufacturing process at various stages, for real time information extraction in RFID implementation scenario. This customer complaint handling system through RFID may provide an opportunity to managers in taking decision for analyzing the customer specific cause and effect relationship between product failure and process optimization. This algorithm can be customized further to meet the needs of other production packaging and packing processes whenever the specifications are not in line. Keywords - Customer complaint, RFID (Radio Frequency Identification), Reverse Logistics.

Digital Signal Processing Techniques to Improve Time Resolution in Positron Emission Tomography

Coincidence time resolution is one of the most important issues in PET detectors. Improving this resolution is required to increase the noise equivalent count rate (NECR) that reduces the noise in the reconstructed images. The aim of this work is to evaluate the behavior and time resolution of different proposed time pick-off algorithms in order to select the best configuration for our PET system. The experimental setup used for this research is composed by two monolithic LSO crystals+PSPMT detectors and an FPGA based PET data acquisition system (DAQ). The acquired signals are sampled using a 12-bit 70 MHz analog to digital converter (ADC) per channel. The setup has no centralized electronics for trigger and event time extraction. Consequently, events for each detector head are processed independently and all the signals are acquired in the same way. Time resolution in this kind of systems can be improved by means of digital processing techniques and using different shapings for the last dynode signals. Four digital algorithms extracting time information from the acquired pulses have been evaluated: (1) Amplitude bipolar digital constant fraction discriminator (BCFD), (2) charge BCFD, (3) interpolated amplitude BCFD and (4) interpolated charge BCFD. Two different architectures for the interpolation algorithm have been used (one-sample and two-sample interpolation), which allow us to work with two different FPGA internal sampling frequencies: 140 MHz and 210 MHz. The results show the importance of selecting the right algorithm and parameters. Time coincidence resolution in our hardware system can be improved by up to 6.9 ns FWHM depending on the chosen digital algorithm programmed on the FPGA. The measurements with our setup reveal that charge based algorithms are less sensitive to signal noise and generate better results than amplitude algorithms. The best configuration achieves a FWHM resolution close to 1.8 ns.

Repetitive ultrafast melting of InSb as an x-ray timing diagnostic

We have demonstrated the possibility of using repetitive ultrafast melting of InSb as a timing diagnostic in connection with visible-light pump∕x-ray probe measurements at high-repetition-rate x-ray facilities. Although the sample was molten and regrown approximately 1×106 times, a distinct reduction in time-resolved x-ray reflectivity could be observed using a streak camera with a time resolution of 2.5ps. The time-resolved x-ray reflectivity displayed this distinct decrease despite the fact that the average reflectivity of the sample had fallen to approximately 50% of its original value due to accumulated damage from the prolonged laser exposure. The topography of the laser-exposed sample was mapped using an optical microscope, a stylus profilometer, photoelectron microscopy, and a scanning tunneling microscope. Although the surface of the sample is not flat following prolonged exposure at laser fluences above 15mJ∕cm2, the atomic scale structure regrows, and thus, regenerates the sample on a nanosecond timescale. In the fluence range between 15 and 25mJ∕cm2, the laser power is sufficient to melt the sample, while regrowth occurs with a sufficiently good structure to allow the extraction of timing information via ultrafast time-resolved x-ray measurements. This can be applied for timing purposes at synchrotron radiation and x-ray free-electron laser facilities. It is also noteworthy that we were able to reproduce the fluence dependencies of melting depth and disordering time previously obtained in single-shot, nonthermal melting experiments with higher temporal resolution.

The time course of action and action-word comprehension in the human brain as revealed by neurophysiology

Numerous previous neuroimaging studies suggest an involvement of cortical motor areas not only in action execution but also in action recognition and understanding. Motor areas of the human brain have also been found to activate during the processing of written and spoken action-related words and sentences. Even more strikingly, stimuli referring to different bodily effectors produced specific somatotopic activation patterns in the motor areas. However, metabolic neuroimaging results can be ambiguous with respect to the processing stage they reflect. This is a serious limitation when hypotheses concerning linguistic processes are tested, since in this case it is usually crucial to distinguish early lexico-semantic processing from strategic effects or mental imagery that may follow lexico-semantic information access. Timing information is therefore pivotal to determine the functional significance of motor areas in action recognition and action-word comprehension. Here, we review attempts to reveal the time course of these processes using neurophysiological methods (EEG, MEG and TMS), in visual and auditory domains. We will highlight the importance of the choice of appropriate paradigms in combination with the corresponding method for the extraction of timing information. The findings will be discussed in the general context of putative brain mechanisms of word and object recognition.

A Neural Model for Context-dependent Sequence Learning

A novel neural network model is described that implements context-dependent learning of complex sequences. The model utilises leaky integrate-and-fire neurons to extract timing information from its input and modifies its weights using a learning rule with synaptic noise. Learning and recall phases are seamlessly integrated so that the network can gradually shift from learning to predicting its input. Experimental results using data from the real-world problem domain demonstrate that the use of context has three important benefits: (a) it prevents catastrophic interference during learning of multiple overlapping sequences, (b) it enables the completion of sequences from missing or noisy patterns, and (c) it provides a mechanism to selectively explore the space of learned sequences during free recall.

Slicing the Beat: Jazz Eighth-Notes as Expressive Microrhythm

Until recently, jazz theorists have directed most of their analytical efforts to unscrambling aspects of pitch rather than time, mimicking the analysis of art music. The perceptual limitations involved in extracting and char acterizing essential rhythmic nuances, as well as the limitations of standard music notation to convey these, have tended to deter rigorous study of the microrhythmic features of jazz performance. In pitch-oriented studies, tempo ral aspects have generally been neglected in favor of scalarand harmonic-re lated topics (e.g., Cogswell 1994;Hermann 2004 Johnson-Laird 2002; Kenny 1999; Larson 2002; Steedman 1984; Toiviainen 1995; Tymoczko 1997). A few other studies have addressed the interaction between the pitch and time domains, although issues of microrhythm are left largely unexplored (e.g., Berliner 1994;Haywood 1994;J?rvinen 1995). An important (and pioneering) exception is that of Pressing (1987), who recorded himself performing two free jazz improvisations and used a computer to extract timing, dynamics, and legatoness information. He found that some of the microrhythmic mechanisms sometimes interacted with melody and phrase structure. Microrhythms in jazz have begun to receive increasing attention from jazz scholars over the last decade, partly as a result of the widespread avail ability of inexpensive and easy to use sound-editing software, and partly as a result of a collective need to catch up with an already advanced pitch-based analytical tradition. However, just as most research on jazz theory has shown a unilateral preference for pitch-related topics, the growing body of work devoted to microrhythm in jazz risks neglecting the interaction between the pitch and time domains. Such is the case with studies where timing consider ations dominate the discussion and pitch information is either excluded from the discussion (Busse 2002; Collier and Collier 1994; Friberg and Sundstr?m 2002;Pr?gler 1995), displayed but excluded from the discussion (Ellis 1991),

U series disequilibria: Insights into mantle melting and the timescales of magma differentiation

Several U series nuclides have half‐lives (230Th, 76 kyr; 231Pa, 33 kyr; and 226Ra, 1.6 kyr) comparable to timescales of magmatic processes. We review the basic principles of extracting time information from U series nuclides and summarize variations in (230Th/238U), (226Ra/230Th), and (231Pa/235U) observed in magmas from mid‐ocean ridges, within‐plate settings, and subduction zones to contrast melt generation processes in different tectonic settings. U series disequilibria on melt and crystal phases of igneous rocks can provide temporal information on different stages in the magmatic history (melting duration, melt transport rates, magmatic crustal residence times, and timing of crystal growth) and potentially provide clues about the nature and mineralogy of mantle sources, mantle upwelling rates and porosity, fluid influences, and mechanisms of melt generation and transport. The subject is beginning to take a genuinely integrated approach to developing physically realistic quantitative models that offer increasingly exciting opportunities in the study of magmatic processes.

High-bandwidth measurement of femtosecond optical pulse timing based on two-dimensional transmission gating and parallel processing

We demonstrate a high-bandwidth, precision timing measurement technique using a surface-normal two-dimensional (2D) all-optical switch and a parallel computational sensor array to achieve high-density, parallel extraction of timing information of femtosecond optical pulses. Optoelectronic parallel processing eliminates the bottleneck of conventional systems and achieves femtosecond precision and robust timing extraction using a simple on-chip algorithm. The timing fluctuation of 1- kHz, 100-fs optical pulses was extracted on a pulse-by-pulse basis.

Trading Volume, Information Asymmetry, and Timing Information

ABSTRACTThis paper investigates trading volume before scheduled and unscheduled corporate announcements to explore how traders respond to private information. I show that cumulative trading volume decreases inversely to information asymmetry prior to scheduled announcements, while the opposite relation holds for volume after the announcement. In contrast, trading volume before unscheduled announcements increases dramatically and shows little relation to proxies for information asymmetry. I investigate the behavior of market makers and find that they act appropriately by increasing price sensitivity before all announcements, implying that they extract timing information from their order books.