Number Of Triggered Events Research Articles

The Calorimetric Electron Telescope (CALET) on the International Space Station: Results from the first eight years on orbit

The Calorimetric Electron Telescope, CALET, is an astroparticle physics mission installed on the International Space Station, ISS. The primary objective of the mission is studying the details of galactic cosmic-ray acceleration and propagation, and searching for the possible nearby sources of high-energy electrons and dark matter signatures. The CALET experiment measure the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma-rays to 10 TeV and nuclei to 1000 TeV. The detector is an all-calorimetric instrument with a total vertical thickness of 30 radiation lengths and fine imaging capability, optimized for the measurement of the electron and positron (all-electron) spectrum well into the TeV energy region. It consists of a charge detector (CHD) with two layers of segmented plastic scintillators for the identification of cosmic-rays via a measurement of their charge over the range Z=1∼40, a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). The instrument was launched on August 19, 2015 to the ISS and installed on the Japanese Experiment Module-Exposed Facility. Since the start of operation in October, 2015, CALET has been collecting scientific data without any major interruption for more than eight years. The number of triggered events over 10 GeV is nearly 1.97 billion events as of November 30, 2023. In this paper, we present the results of the CALET mission so far, including the all-electron energy spectrum, the spectra of protons and other nuclei, gamma-ray observations, as well as the characterization of on-orbit performance. Some results on the electromagnetic counterpart search for LIGO/Virgo gravitational wave events and the observations of solar modulation and gamma-ray bursts are also included.

Relative motion splints versus metacarpophalangeal joint blocking splints in the management of trigger finger: Study protocol for a randomized comparative trial.

Evidence supports the use of hand-based metacarpophalangeal joint (MCPJ) blocking splints as an intervention for trigger finger (TF). In practice, finger-based relative motion (RM) splints are also implemented without evidence. This randomized comparative trial (RCT) aims to evaluate implementation of MCPJ blocking and RM splints for effectiveness, function, occupational performance and wearability after 6 weeks of TF management. Priori analysis determined 36 individuals were needed for random assignment to the RM or MCPJ blocking splint groups. Individuals must be aged ≥21 years, and diagnosed with TF involving ≥1 finger. For blinding purposes, the primary author screens for eligibility, fabricates the splints and educates. Therapist A administers the primary outcome measures Week-1 and Week-6-stage of stenosing tenosynovitis and secondary outcome measures- number of triggering events in 10 active fists, visual analog scales (VAS) for pain, splint comfort and satisfaction, Disabilities of the Arm, Shoulder and Hand, and Canadian Occupational Performance Measure. Therapist B in Week-3 instructs participants in deep tissue massage and administers splint wearability VASs. The RM pencil test is used to determine the affected finger(s) MCPJ splint position i.e., more extension or flexion based on participant response. The MCPJ blocking splint holds the MCPJ in a neutral position. Analysis involves a mixed-effects ANOVA to compare Week-1 and Week-6 primary and secondary outcomes. Recruitment and data collection are ongoing. Biomechanically RM splints control tendon excursion and reduce passive tendon tension while allowing unencumbered finger motion and hand function. Hence clinicians use RM splints as an intervention for TF, despite the lack of implementation evidence. This RCT implements a function-focused as well as patient-centered approach with partial blinding of assessors and participants. We anticipate that this study will provide evidence for the implementation of RM splints to manage adults with TF. Clinical trial registration This trial is registered with ClinicalTrials.gov (NCT05763017).

Prediction of disability in trigger finger: a cross-sectional and longitudinal study.

The aim of this prospective study of 55 patients was to analyse the cross-sectional and longitudinal relationship between disability and physical and psychological variables after conservative treatment of trigger finger and to determine the predictive factors for the post-treatment disability score and change in disability score. The primary outcome measure was the Disabilities of the Arm, Shoulder, and Hand questionnaire. Potential predictive factors included pain, number of triggering events, depression, anxiety and kinesiophobia. Disability correlated strongly with anxiety, moderately with pain and depression and weakly with triggering and kinesiophobia. The change in depression score correlated significantly with the change in disability score. Post-treatment pain and anxiety scores accounted for 47% of the explained variance in disability score. Improvement in depression after treatment accounted for 18% of the explained variance in disability change score. Psychological variables appear to be potential predictors of disability.Level of evidence: IV.

A proximal interphalangeal joint custom-made orthosis in trigger finger: Functional outcome.

Trigger finger is a common and functionally limiting disorder. Finger immobilization using an orthotic device is one of the conservative treatment options for treating this condition. The most common orthosis previously described for trigger finger is metacarpophalangeal joint immobilization. There are limited studies describing the effectiveness of proximal interphalangeal joint orthosis for treatment of trigger finger. This study was a single group pretest-posttest design. Adult patients with single digit idiopathic trigger finger were recruited and asked to wear a full-time orthoses for 6 weeks. The pre- and post-outcome measures included Quick-DASH score, the Stages of Stenosing Tenosynovitis (SST), the Visual Analogue Scale (VAS) for pain, the number of triggering events in ten active fists, and participant satisfaction with symptom improvement. Orthotic devices were made with thermoplastic material fabricated with adjustable Velcro tape at the dorsal side. All participants were given written handouts on this disease, orthotic care and gliding exercises. Paired t-tests were used to determine changes in outcome measures before and after wearing the orthosis. There were 30 participants included in this study. Evaluation after the use of PIP joint orthosis at 6 weeks revealed that there were statistically significant improvements in Quick-DASH score from enrolment (mean difference -29.0 (95%CI -34.5 to -23.4); p < 0.001), SST (mean difference -1.4 (95%CI -1.8 to -1.0); p < 0.001) and VAS (mean difference -3.4 (95%CI -4.3 to -2.5); p < 0.001). There were no serious adverse events and patient satisfaction with the treatment was high. Despite our small study size, the use of proximal interphalangeal joint orthosis for 6 weeks resulted in statistically significant improvements in function, pain and triggering, and also high rates of acceptance in patients with isolated idiopathic trigger finger.

Adaptive fuzzy guaranteed performance control for uncertain nonlinear systems with event-triggered input

This paper investigates the issue of event-triggered adaptive tracking control for a class of nonlinear systems with unmeasurable states and uncertain nonlinearities. A state observer based on fuzzy logic systems (FLSs) is first established for further stability analysis. Under the framework of backstepping technique, a novel adaptive backstepping control scheme is proposed, where the controller updates are event-driven to decrease the communication burden between the plant and the controller. Differing from the existing results for periodic event-triggered control (ETC), the proposed event-triggered strategy is aperiodic, which depends on the measurement errors with respect to fixed threshold and the magnitude of control signal. Especially, it should be mentioned that the discontinuous control signals in ETC might bring poor transient performance. Therefore, the prescribed performance bounds (PPBs) method with barrier Lyapunov function is utilized to balance the system performance and the number of triggering events. Finally, it is proved that all closed-loop signals can converge to a desired compact set and the output tracking error is within the specified bounds. Simulation example illustrates the effectiveness of the proposed control scheme.

The CALorimetric Electron Telescope (CALET) on the International Space Station

The CALorimetric Electron Telescope (CALET) space experiment, developed by Japan in collaboration with Italy and the United States, is a high-energy astroparticle physics mission installed on the International Space Station (ISS). The primary goals of the CALET mission include investigating on the possible presence of nearby sources of high-energy electrons, studying the details of galactic particle propagation and searching for dark matter signatures. During a two-year mission, extendable to five years, CALET can measure the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma-rays to 10 TeV and nuclei with Z = 1 to 40 up to 1,000 TeV. The instrument consists of two layers of segmented plastic scintillators for cosmic-ray charge identification (CHD), a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). CALET has sufficient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma rays. The instrument was launched on August 19, 2015 to the ISS with the H-II Transfer Vehicle 5 (HTV-5) and installed on the Japanese Experiment Module-Exposed Facility (JEM-EF) on August 25. Since the start of operations in mid-October, 2015, a continuous observation has been going on mainly by triggering high energy (>10 GeV) showers without any major interruption. The number of triggered events above 10 GeV is nearly 20 million per month. By using the data obtained during the first two years, we give a summary of CALET observations: (1) Electron + Positron energy spectrum, (2) Proton and Nuclei spectrum, (3) Gamma-ray observation, with results of the performance study on orbit. We also present the results of observations of the electromagnetic counterparts to LIGO-VIRGO gravitational wave events and high-energy counterparts to GRB events measured with the CALET Gamma-ray Burst Monitor (CGBM).

Event-triggered robust cooperative stabilization in nonlinearly interconnected multiagent systems

By way of the graph theoretic tools, we model closed-loop large-scale systems as two-layer multiagent systems with the agent layer describing nonlinearly interconnected dynamics and the control layer designed to stabilize the system by communications in agents’ neighborhoods. We consider a scenario in which the effect of dynamical interactions over the agent layer appears through some nonlinear functions which are in the range space of the control input matrix, yet the underlying agent layer interconnection topology and the associated nonlinearities are not known to the control layer designer. We develop a static linear cooperative algorithm and, having endowed each local controller with several buffers, we schedule the control layer information exchange events in a non-periodic non-synchronous manner. We combine graph theoretic and event triggering ideas with an optimal control formulation, and propose a design procedure to obtain the required robust control gain. We prove that all trajectories of the closed-loop multiagent system will exponentially converge to the origin in the presence of time-varying nonlinearly interconnected modeling uncertainties over agent layer. For the same cooperative stabilization algorithm, trading off with the exponential convergence to a neighborhood around the origin, we further show that a practical event triggering mechanism can be developed to better deal with the effect of modeling mismatch on the number of triggering events. We also prove the proposed event triggering mechanisms do not exhibit Zeno behavior to ensure the feasibility of the proposed ideas in the sense of reduced communication load and, thereby, energy consumption.

The CALorimetric Electron Telescope (CALET) on the International Space Station: Results from the First Two Years of Operation

The CALorimetric Electron Telescope (CALET) space experiment, which has been developed by Japan in collaboration with Italy and the United States, is a high-energy astroparticle physics mission on the International Space Station (ISS). The primary goals of the CALET mission include investigation of possible nearby sources of high-energy electrons, detailed study of galactic cosmic-ray acceleration and propagation, and search for dark matter signatures. With a long-term observation onboard the ISS, the CALET experiment measures the flux of cosmic-ray electrons (including positrons) up to 20 TeV, gamma-rays to 10 TeV, and nuclei up to 1,000 TeV based on its charge separation capability from Z = 1 to 40. Since the start of science operation in mid-October, 2015, a continuous observation has been maintained without any major interruptions. The number of triggered events over 10 GeV is nearly 20 million per month. By using the data obtained during the first two-years, here we present a summary of the CALET observations: 1) Electron+positron energy spectrum, 2) Nuclei analysis, 3) Gamma-ray observation with a characterization of the on-orbit performance. The search results for the electromagnetic counterparts of LIGO/Virgo gravitational wave events are also discussed.

Metacognitive beliefs and rumination as predictors of anger: A prospective study.

The metacognitive approach conceptualizes the relationship between anger and rumination as driven by metacognitive beliefs, which are information individuals hold about their own cognition and about coping strategies that impact on it. The present study aimed to test the prospective predictive impact of metacognitive beliefs and rumination on anger in a community sample. Seventy-six participants were recruited and engaged in a 2-week anger, rumination, and metacognitive beliefs monitoring protocol. A multi-wave panel design was employed to test whether metacognitive beliefs and rumination have a prospective impact on anger. Metacognitive beliefs and rumination were found to have a significant prospective impact on anger that was independent from the number of triggering events. Metacognitive beliefs about the need to control thoughts were shown to have a direct impact on subsequent anger, independently from rumination. These findings provide support for the potential value for applying metacognitive theory and therapy to anger-related problems. Aggr. Behav. 43:421-429, 2017. © 2017 Wiley Periodicals, Inc.

Searching for Anomalous Longitudinal Profiles with the FRAM Telescope

The study of anomalous longitudinal profiles of extensive air showers presents an interesting opportunity to gain additional insight about the character of hadronic interactions at the highest energies. Moreover, the presence of such profiles would represent direct evidence of a light component in the primary cosmic rays of a given energy, independently of hadronic interaction models. The ratio of profiles observed to have a “double bump” structure (with two clearly distinguishable atmospheric depths of maximum particle count) compared to the total number of events can moreover be used to test the predictions of interaction models. However, the majority of such profiles observed at the Pierre Auger Observatory are caused by clouds. Here we describe a method of rapid monitoring of particularly interesting cosmic ray events, using the F/Photometric Rapid Atmospheric Monitor (FRAM) telescope to identify events with clear, cloudless atmospheric background. The function of FRAM is described in detail and the number of triggered events is presented.

Statistical tests on clustered global earthquake synthetic data sets

AbstractWe study the ability of statistical tests to identify nonrandom features of earthquake catalogs, with a focus on the global earthquake record since 1900. We construct four types of synthetic data sets containing varying strengths of clustering, with each data set containing on average 10,000 events over 100 years with magnitudes above M = 6. We apply a suite of statistical tests to each synthetic realization in order to evaluate the ability of each test to identify the sequences of events as nonrandom. Our results show that detection ability is dependent on the quantity of data, the nature of the type of clustering, and the specific signal used in the statistical test. Data sets that exhibit a stronger variation in the seismicity rate are generally easier to identify as nonrandom for a given background rate. We also show that we can address this problem in a Bayesian framework, with the clustered data sets as prior distributions. Using this new Bayesian approach, we can place quantitative bounds on the range of possible clustering strengths that are consistent with the global earthquake data. At M = 7, we can estimate 99th percentile confidence bounds on the number of triggered events, with an upper bound of 20% of the catalog for global aftershock sequences, with a stronger upper bound on the fraction of triggered events of 10% for long‐term event clusters. At M = 8, the bounds are less strict due to the reduced number of events. However, our analysis shows that other types of clustering could be present in the data that we are unable to detect. Our results aid in the interpretation of the results of statistical tests on earthquake catalogs, both worldwide and regionally.

Suboptimal Event-Triggered Consensus of Multiagent Systems

In this paper the suboptimal event-triggered consensus problem of Multiagent systems is investigated. Using the combinational measurement approach, each agent only updates its control input at its own event time instants. Thus the total number of events and the amount of controller updates can be significantly reduced in practice. Then, based on the observation of increasing the consensus rate and reducing the number of triggering events, we have proposed the time-average cost of the agent system and developed a suboptimal approach to determine the triggering condition. The effectiveness of the proposed strategy is illustrated by numerical examples.

Response of seismicity to static and dynamic stress changes induced by the 2011 M9.0 Tohoku‐Oki earthquake

AbstractA growing body of evidence indicates that many earthquakes are triggered by static and dynamic stress changes following large earthquakes. However, it has been difficult to differentiate the roles of static and dynamic stress transfer on earthquake triggering. Here we focus on two adjacent seismic clusters aligned E‐W beneath the Hida Mountain Range, central Japan, where spatially uniform static and dynamic stress changes resulted from the Tohoku‐Oki earthquake. The rate of seismicity in the western cluster, detected by the matched filter technique, showed a slight increase after the mainshock, which can be explained by static stress transfer. In contrast, seismicity in the eastern cluster showed a marked increase due to dynamic stress change. The difference in the number of triggered events between these clusters indicates that dynamic stress change is more important than the static one in terms of remote triggering, provided that large‐sized potential earthquake‐nucleation patches are close to failure.

A rate-state model for aftershocks triggered by dislocation on a rectangular fault: a review and new insights

We compute the static displacement, stress, strain and the Coulomb failure stress produced in an elastic medium by a finite size rectangular fault after its dislocation with uniform stress-drop but a non uniform dislocation on the source. The time-dependent rate of triggered earthquakes is estimated by a rate-state model applied to a uniformly distributed population of faults whose equilibrium is perturbed by a stress change caused only by the first dislocation. The rate of triggered events in our simulations is exponentially proportional to the shear stress change, but the time at which the maximum rate begins to decrease is variable from fractions of hour for positive stress changes of the order of some MPa, up to more than a year for smaller stress changes. As a consequence, the final number of triggered events is proportional to the shear stress change. The model predicts that the total number of events triggered on a plane containing the fault is proportional to the 2/3 power of the seismic moment. Indeed, the total number of aftershocks produced on the fault plane scales in magnitude, M, as 10 M . Including the negative contribution of the stress-drop inside the source, we observe that the number of events inhibited on the fault is, at long term, nearly identical to the number of those induced outside, representing a sort of conservative natural rule. Considering its behavior in time, our model does not completely match the popular Omori Law; in fact it has been shown that the seismicity induced closely to the fault edges is intense but of short duration, while that expected at large distances (up to some tens times the fault dimensions) exhibits a much slower decay.

Effectiveness of Splinting for the Treatment of Trigger Finger

The purpose of this study was to evaluate the efficacy of custom thermoplastic splinting designed to limit metacarpalphalangeal (MCP) joint flexion for trigger finger as a first treatment option. This study was a single group, prepost design with 28 participants fit with a low-profile custom thermoplastic MCP blocking (ring) splint. The pre- and post outcome measures included: stages of stenosing tenosynovitis (SST), grip strength, Numeric Pain Rating Scale (NPRS), the number of triggering events in ten active fists, and participant perceived improvement in symptoms. These measures were taken at the time of initial assessment before splint fabrication and after six weeks of continuous splint wear. Participants were given an educational handout on trigger finger and exercises to complete independently. After the use of a splint, there were statistically significant improvements in the SST, NPRS, the number of triggering events in ten active fists, and in the participant perceived improvement in symptoms. Grip strength did not significantly change. This study demonstrated a benefit from the use of a custom thermoplastic splint for an isolated incidence of trigger finger based on chosen outcome measures.

Earthquake triggering in southern Iceland following the June 2000 Ms 6.6 doublet

In June 2000, two remarkably similar Ms 6.6 earthquakes stroke southern Iceland in the space of 3 d. Here this doublet is analyzed to test whether aftershock triggering is linear, that is, if the triggering patterns of these two similar main shocks are also similar. Methodologically, the key issue is to separate the two contributions to the overall seismicity patterns. For this purpose, we model the first 3 d (17–21 June) of this aftershock sequence with an Omori‐Utsu law. We then extrapolate it beyond 21 June in order to estimate the variations linked with the second shock. We correct for the large transient changes in catalogue completeness. Our results indicate that instantaneous short‐lived (hours to days) dynamic triggering took place at the Hengill Triple Junction, on the Reykjanes Peninsula, and around the Árnes fault plane that ruptured on 17 June. We observe delayed, long‐lasting (longer than weeks) episodes of quiescence at Hengill and on the Árnes fault plane. At Hengill this quiescence remains significant up to at least the end of 2000. These quiescences are more consistent with Coulomb stress calculations than the preceding episodes of triggering. Comparison between the number of triggered events by the two main shocks reveals that the second one triggered only 2.1% at Hengill and 0.3% at Reykjanes of the number (3.6% and 0.1%, respectively, of the seismic moment) that could be expected with a simple stress threshold model of dynamic triggering. This clear nonlinearity in patterns of dynamic triggering is consistent with a model in which the population of nucleating earthquakes is depleted by the first trigger.

Variations in dead-time corrections for multiplicity measurements made with paralysable and nonparalysable systems

Expressions are produced, for a nonparalysable counting system, giving the probability of a particular number of dead-time losses from a given number of triggering events during a time window (gate) of known length. The input events are assumed to have a Poisson distribution. Calculations by Vincent giving related expressions for dead-time losses in a paralysable counting system are confirmed. Consistency checks and comparisons are made. The probabilities for both paralysable and nonparalysable counting systems are expressed in forms suitable for calculations and for comparisons.