Articles de revues : « TIMED BEHAVIOR »

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PETERS, J. F., et S. RAMANNA. « MODELING TIMED BEHAVIOR IN REAL-TIME SYSTEMS WITH TEMPORAL LOGIC ». Cybernetics and Systems 22, n^o 5 (septembre 1991) : 583–608. http://dx.doi.org/10.1080/01969729108902301.

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NAKATA, AKIO, TADAAKI TANIMOTO, SUGURU SASAKI et TERUO HIGASHINO. « A TIMED FAILURE EQUIVALENCE PRESERVING ABSTRACTION FOR PARAMETRIC TIME-INTERVAL AUTOMATA ». International Journal of Foundations of Computer Science 17, n^o 04 (août 2006) : 833–49. http://dx.doi.org/10.1142/s0129054106004133.

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In the development of real-time communicating hardware/embedded-software systems, it is frequently the case that we want to refine/optimize the system's internal behavior while preserving the external timed I/O behavior. In such a design refinement, modification of the systems' internal branching structures, as well as re-scheduling of internal actions, may frequently occur. Our goal is, then, to ensure that such modification of internal branching structures and re-scheduling of internal actions preserve the systems' external timed behavior, which is typically formalized by the notion of (timed) failure equivalence since it is less sensitive to the difference of internal branching structures than (timed) weak bisimulation. In order to know the degree of freedom of such re-scheduling, parametric analysis is useful. One of the models suitable for such an analysis is a parametric time-interval automaton(PTIA), which is a subclass of the existing model, a parametric timed automaton. It has only a time interval with upper- and lower-bound parameters as a relative timing constraint between consecutive actions. In this paper, at first, we propose an abstraction algorithm of PTIA which preserves timed failure equivalence. Timed failure equivalence is strictly weaker than timed weak bisimulation in the sense that it does not distinguish the difference of the timing when the internal resolution of nondeterminism has occurred, but it does distinguish the difference of the refusals of communicating actions observed by an external environment. Then, we also show that after applying our algorithm, the reduced PTIA has no internal actions, and thus the problem deriving a parameter condition in order that given two models are timed failure equivalent can be reduced to the existing parametric strong bisimulation equivalence checking.

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Tosun, Tuğçe, Ezgi Gür et Fuat Balcı. « Mice plan decision strategies based on previously learned time intervals, locations, and probabilities ». Proceedings of the National Academy of Sciences 113, n^o 3 (5 janvier 2016) : 787–92. http://dx.doi.org/10.1073/pnas.1518316113.

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Animals can shape their timed behaviors based on experienced probabilistic relations in a nearly optimal fashion. On the other hand, it is not clear if they adopt these timed decisions by making computations based on previously learnt task parameters (time intervals, locations, and probabilities) or if they gradually develop their decisions based on trial and error. To address this question, we tested mice in the timed-switching task, which required them to anticipate when (after a short or long delay) and at which of the two delay locations a reward would be presented. The probability of short trials differed between test groups in two experiments. Critically, we first trained mice on relevant task parameters by signaling the active trial with a discriminative stimulus and delivered the corresponding reward after the associated delay without any response requirement (without inducing switching behavior). During the test phase, both options were presented simultaneously to characterize the emergence and temporal characteristics of the switching behavior. Mice exhibited timed-switching behavior starting from the first few test trials, and their performance remained stable throughout testing in the majority of the conditions. Furthermore, as the probability of the short trial increased, mice waited longer before switching from the short to long location (experiment 1). These behavioral adjustments were in directions predicted by reward maximization. These results suggest that rather than gradually adjusting their time-dependent choice behavior, mice abruptly adopted temporal decision strategies by directly integrating their previous knowledge of task parameters into their timed behavior, supporting the model-based representational account of temporal risk assessment.

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Niggemann, Oliver, Benno Stein, Asmir Vodencarevic, Alexander Maier et Hans Kleine Büning. « Learning Behavior Models for Hybrid Timed Systems ». Proceedings of the AAAI Conference on Artificial Intelligence 26, n^o 1 (20 septembre 2021) : 1083–90. http://dx.doi.org/10.1609/aaai.v26i1.8296.

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A tailored model of a system is the prerequisite for various analysis tasks, such as anomaly detection, fault identification, or quality assurance. This paper deals with the algorithmic learning of a system’s behavior model given a sample of observations. In particular, we consider real-world production plants where the learned model must capture timing behavior, dependencies between system variables, as well as mode switches—in short: hybrid system’s characteristics. Usually, such model formation tasks are solved by human engineers, entailing the well-known bunch of problems including knowledge acquisition, development cost, or lack of experience. Our contributions to the outlined field are as follows. (1) We present a taxonomy of learning problems related to model formation tasks. As a result, an important open learning problem for the domain of production system is identified: The learning of hybrid timed automata. (2) For this class of models, the learning algorithm HyBUTLA is presented. This algorithm is the first of its kind to solve the underlying model formation problem at scalable precision. (3) We present two case studies that illustrate the usability of this approach in realistic settings. (4) We give a proof for the learning and runtime properties of HyBUTLA.

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Zhang, Yihuan, Qin Lin, Jun Wang et Sicco Verwer. « Car-following Behavior Model Learning Using Timed Automata ». IFAC-PapersOnLine 50, n^o 1 (juillet 2017) : 2353–58. http://dx.doi.org/10.1016/j.ifacol.2017.08.423.

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Mathes, M. Todd, Scott G. Hinch, Steven J. Cooke, Glenn T. Crossin, David A. Patterson, Andrew G. Lotto et Anthony P. Farrell. « Effect of water temperature, timing, physiological condition, and lake thermal refugia on migrating adult Weaver Creek sockeye salmon (Oncorhynchus nerka) ». Canadian Journal of Fisheries and Aquatic Sciences 67, n^o 1 (janvier 2010) : 70–84. http://dx.doi.org/10.1139/f09-158.

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We coupled physiological biopsy and positional telemetry to examine survival to reach spawning grounds in relation to water temperature, timing, physiological condition, and holding location (river or lake) in adult migrating sockeye salmon ( Oncorhynchus nerka ). We tracked 83 fish across a large temperature range (13.5–21.5 °C), which included record highs. Only early-timed migrants that held in Harrison Lake survived to reach spawning grounds (16%, or n = 4). Normal-timed fish, those that migrated at historically observed times, survived at higher levels if they held in Harrison River (72%, or n = 18). Mortalities were identified on the bottoms of both the lake and river. Hypothetical degree-day (DD) accumulation revealed that early-timed river fish would have greatly surpassed (~800 °C DD) a critical disease threshold value (~500 °C DD). There was no difference in hypothetical DD accumulation between normal-timed river fish and early-timed lake fish. Early-timed sockeye had elevated physiological stress (e.g., plasma lactate, glucose, and hematocrit), which may have contributed to high levels of mortality. By using lakes as thermal refugia, early-timed fish likely reduce rates of disease development and may better recover from physiological stress associated with high encountered temperatures.

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Brasic, James Robert, Jacqueline Y. Barnett, Seok Cheol Ahn, Robert H. Nadrich, Michael V. Will et Andrea Clair. « Clinical Assessment of Self-Injurious Behavior ». Psychological Reports 80, n^o 1 (février 1997) : 155–60. http://dx.doi.org/10.2466/pr0.1997.80.1.155.

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The Timed Self-injurious Behavior Scale is an observational scale rating the frequency of 16 types of self-injurious behaviors during each 10-sec. interval of a 10-min. observation period. Advantages of the scale are utilization of direct observation and independence from the variable recollection of symptoms by subjects and care givers. 19 videotaped sessions of a subject who exhibited eight types of self-injurious behaviors were rated with the scale independently by three raters. Eighty percent and better agreement was found for the four specific forms of those behaviors exhibited by the subject sufficiently frequently, self biting, head punching, head slapping, and hair removal.

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Kim, Ja-Hee. « An Asymptotic Cyclicity Analysis of Live Autonomous Timed Event Graphs ». Applied Sciences 11, n^o 11 (22 mai 2021) : 4769. http://dx.doi.org/10.3390/app11114769.

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Designing a discrete event system converging to steady temporal patterns is an essential issue of a system with time window constraints. Until now, to analyze asymptotic stability, we have modeled a timed event graph’s dynamic behavior, transformed it into the matrix form of (max,+) algebra, and then constructed a precedence graph. This article’s aim is to provide a theoretical basis for analyzing the stability and cyclicity of timed event graphs without using (max,+) algebra. In this article, we propose converting one timed event graph to another with a dynamic behavior equivalent to that of the original without going through the conversion process. This paper also guarantees that the derived final timed event graph has the properties of a precedence graph. It then investigates the relationship between the properties of the derived precedence graph and that of the original timed event graph. Finally, we propose a method to analyze asymptotic cyclicity and stability for a given timed event graph by itself. The analysis this article provides makes it easy to analyze and improve asymptotic time patterns of tasks in a given discrete event system modeled with a live autonomous timed event graph such as repetitive production scheduling.

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Colvin, Robert, Lars Grunske et Kirsten Winter. « Timed Behavior Trees for Failure Mode and Effects Analysis of time-critical systems ». Journal of Systems and Software 81, n^o 12 (décembre 2008) : 2163–82. http://dx.doi.org/10.1016/j.jss.2008.04.035.

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Ferringer, Markus. « On Self-Timed Circuits in Real-Time Systems ». International Journal of Reconfigurable Computing 2011 (2011) : 1–16. http://dx.doi.org/10.1155/2011/972375.

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While asynchronous logic has many potential advantages compared to traditional synchronous designs, one of the major drawbacks is its unpredictability with respect to temporal behavior. Having no high-precision oscillator, a self-timed circuit's execution speed is heavily dependent on temperature and supply voltage. Small fluctuations of these parameters already result in noticeable changes of the design's throughput and performance. Without further provisions this jitter makes the use of asynchronous logic hardly feasible for real-time applications. We investigate the temporal characteristics of self-timed circuits regarding their usage in real-time systems, especially the Time-Triggered Protocol. We propose a simple timing model and elaborate a self-adapting circuit which shall derive a suitable notion of time for both bit transmission and protocol execution. We further introduce and analyze our jitter compensation concept, which is a threefold mechanism to keep the asynchronous circuit's notion of time tightly synchronized to the remaining communication participants. To demonstrate the robustness of our solution, we perform different tests and investigate their impact on jitter and frequency stability.

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Tigane, Samir, Fayçal Guerrouf, Nadia Hamani, Laid Kahloul, Mohamed Khalgui et Masood Ashraf Ali. « Dynamic Timed Automata for Reconfigurable System Modeling and Verification ». Axioms 12, n^o 3 (22 février 2023) : 230. http://dx.doi.org/10.3390/axioms12030230.

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Modern discrete-event systems (DESs) are often characterized by their dynamic structures enabling highly flexible behaviors that can respond in real time to volatile environments. On the other hand, timed automata (TA) are powerful tools used to design various DESs. However, they lack the ability to naturally describe dynamic-structure reconfigurable systems. Indeed, TA are characterized by their rigid structures, which cannot handle the complexity of dynamic structures. To overcome this limitation, we propose an extension to TA, called dynamic timed automata (DTA), enabling the modeling and verification of reconfigurable systems. Additionally, we present a new algorithm that transforms DTA into semantic-equivalent TA while preserving their behavior. We demonstrate the usefulness and applicability of this new modeling and verification technique using an illustrative example.

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PINHANEZ, CLAUDIO S. « BEHAVIOR-BASED ACTIVE VISION ». International Journal of Pattern Recognition and Artificial Intelligence 08, n^o 06 (décembre 1994) : 1493–526. http://dx.doi.org/10.1142/s0218001494000723.

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A vision system was built using a behavior-based model, the subsumption architecture. The so-called active eye moves the camera’s axis through the environment, detecting areas with high concentration of edges, with the help of a kind of saccadic movement. The design and implementation process is detailed in the article, paying particular attention to the fovea-like sensor structure which enables the active eye to efficiently use local information to control its movements. Numerical measures for the eye’s behavior were developed, and applied to evaluate the incremental building process and the effects of the saccadic movements on the whole system. A higher level behavior was also implemented, with the purpose of detecting long straight edges in the image, producing pictures similar to hand drawings. Robustness and efficiency problems are addressed at the end of the paper. The results seem to prove that interesting behaviors can be achieved using simple vision methods and algorithms, if their results are properly interconnected and timed.

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LI, GUOQIANG, XIAOJUAN CAI et SHOJI YUEN. « MODELING AND ANALYSIS OF REAL-TIME SYSTEMS WITH MUTEX COMPONENTS ». International Journal of Foundations of Computer Science 23, n^o 04 (juin 2012) : 831–51. http://dx.doi.org/10.1142/s0129054112400382.

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Timed automata are commonly recognized as a formal behavioral model for real-time systems. For compositional system design, parallel composition of timed automata as proposed by Larsen et al. [22] is useful. Although parallel composition provides a general method for system construction, in the low level behavior, components often behave sequentially by passing control via communication. This paper proposes a behavioral model, named controller automata, to combine timed automata by focusing on the control passing between components. In a controller automaton, to each state a timed automaton is assigned. A timed automaton at a state may be preempted by the control passing to another state by a global labeled transition. A controller automaton properly extends the expressive power because of the stack, but this can make the reachability problem undecidable. Given a strict partial order over states, we show that this problem can be avoided and a controller automaton can be faithfully translated into a timed automaton.

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Srivastava, Kyle H., Caroline M. Holmes, Michiel Vellema, Andrea R. Pack, Coen P. H. Elemans, Ilya Nemenman et Samuel J. Sober. « Motor control by precisely timed spike patterns ». Proceedings of the National Academy of Sciences 114, n^o 5 (18 janvier 2017) : 1171–76. http://dx.doi.org/10.1073/pnas.1611734114.

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A fundamental problem in neuroscience is understanding how sequences of action potentials (“spikes”) encode information about sensory signals and motor outputs. Although traditional theories assume that this information is conveyed by the total number of spikes fired within a specified time interval (spike rate), recent studies have shown that additional information is carried by the millisecond-scale timing patterns of action potentials (spike timing). However, it is unknown whether or how subtle differences in spike timing drive differences in perception or behavior, leaving it unclear whether the information in spike timing actually plays a role in brain function. By examining the activity of individual motor units (the muscle fibers innervated by a single motor neuron) and manipulating patterns of activation of these neurons, we provide both correlative and causal evidence that the nervous system uses millisecond-scale variations in the timing of spikes within multispike patterns to control a vertebrate behavior—namely, respiration in the Bengalese finch, a songbird. These findings suggest that a fundamental assumption of current theories of motor coding requires revision.

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Tahiri, Imane, Alexandre Philippot, Véronique Carré-Ménétrier et Bernard Riera. « A Fault-Tolerant and Reconfigurable Control Framework : Modeling, Design, and Synthesis ». Processes 11, n^o 3 (26 février 2023) : 701. http://dx.doi.org/10.3390/pr11030701.

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Manufacturing systems (MS) have become increasingly complex due to constraints induced by a changing environment, such as flexibility, availability, competition, and key performance indicators. This change has led to a need for flexible systems capable of adapting to production changes while meeting productivity and quality criteria and reducing the risk of failures. This paper provides a methodology for designing reconfigurable and fault-tolerant control for implementation in a Programmable Logic Controller (PLC). The main contribution of this methodology is based on a safe control synthesis founded on timed properties. If a sensor fault is detected, the controller switches from normal behavior to a degraded one, where timed information replaces the information lost from the faulty sensor. Switching between normal and degraded behaviors is ensured through reconfiguration rules. The primary objective of this method is to implement the obtained control into a PLC. In order to achieve this goal, a method is proposed to translate the controllers of the two behaving modes and the reconfiguration rules into different Grafcets. This approach relies on the modular architecture of manufacturing systems to avoid the combinatorial explosion that occurs in several approaches.

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Daszczuk, Wiktor B. « Modeling and Verification of Asynchronous Systems Using Timed Integrated Model of Distributed Systems ». Sensors 22, n^o 3 (3 février 2022) : 1157. http://dx.doi.org/10.3390/s22031157.

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In modern computer systems, distributed systems play an increasingly important role, and modeling and verification are crucial in their development. The specificity of many systems requires taking this into account in real time, as time dependencies significantly affect the system’s behavior, when achieving the goals of its processes or with adverse phenomena such as deadlocks. The natural features of distributed systems include the asynchrony of actions and communication, the autonomy of nodes, and the locality of behavior, i.e., independence from any global or non-local features. Most modeling formalisms are derived from parallel centralized systems, in which the behavior of components depends on the global state or the simultaneous achievement of certain states by components. This approach is unrealistic for distributed systems. This article presents the formalism of a timed integrated model of distributed systems that supports all of the mentioned features. The formalism is based on the relation between the states of the distributed nodes and the messages of distributed computations, called agents. This relation creates system actions. A specification in this formalism can be translated into timed automata, the most popular formalism for specifying and verifying timed parallel systems. The translation rules ensure that the semantics of T-IMDS and timed automata are consistent, allowing use of the Uppaal validator for system verification. The development of general formulas for checking the deadlock freedom and termination efficiency allows for automated verification, without learning temporal logics and time-dependent formulas. An important and rare feature is the finding of partial deadlocks, because in a distributed system a common situation occurs in which some nodes/processes are deadlocked, while others work. Examples of checking timed distributed systems are included.

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Muñoz, Doyra Mariela, Antonio Correcher, Emilio García et Francisco Morant. « Identification of Stochastic Timed Discrete Event Systems with st-IPN ». Mathematical Problems in Engineering 2014 (2014) : 1–21. http://dx.doi.org/10.1155/2014/835312.

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This paper presents a method for the identification of stochastic timed discrete event systems, based on the analysis of the behavior of the input and output signals, arranged in a timeline. To achieve this goal stochastic timed interpreted Petri nets are defined. These nets link timed discrete event systems modelling with stochastic time modelling. The procedure starts with the observation of the input/output signals; these signals are converted into events, so that the sequence of events is the observed language. This language arrives to an identifier that builds a stochastic timed interpreted Petri net which generates the same language. The identified model is a deterministic generator of the observed language. The identification method also includes an algorithm that determines when the identification process is over.

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Gaujal, Bruno, et Alessandro Giua. « Optimal stationary behavior for a class of timed continuous Petri nets ». Automatica 40, n^o 9 (septembre 2004) : 1505–16. http://dx.doi.org/10.1016/j.automatica.2004.04.018.

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Yang, Xiaoxian, Tao Yu et Huahu Xu. « A Novel Framework of Using Petri Net to Timed Service Business Process Modeling ». International Journal of Software Engineering and Knowledge Engineering 26, n^o 04 (mai 2016) : 633–52. http://dx.doi.org/10.1142/s0218194016400052.

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In open and changeful Internet, the enterprise business process needs to be organized or restructured dynamically in order to adapt to environment changes and business logic updates. The solution of Web service and service-oriented architecture (SOA) provides a promising approach. The business processes working as a temporary workflow can be composed by distributed services. However, the cross-organizational service feature of business process requires considering not only the functional requirements but also the timed constraints. The timed property plays an important role in service interactions between business processes, such as timed activity, timeout and timed deadlock. Thus, if time requirements cannot be guaranteed, the new created business process will not be acceptable. In this paper, it proposes a framework of using Petri Net to model timed service business process. First, it defines the behavior model of service business process and gives process composition patterns for different structural forms. Second, service model is extended with time specifications, describing timed constraints among business activity interactions. Third, to support further verifications, it introduces a method for the automatic timed properties generation in the form of temporal logic formulae. Our framework gives a reference in practice to formalize service business process into timed service model.

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Hubbard, Elizabeth A., et Robert W. Motl. « Sedentary behavior is associated with disability status and walking performance, but not cognitive function, in multiple sclerosis ». Applied Physiology, Nutrition, and Metabolism 40, n^o 2 (février 2015) : 203–6. http://dx.doi.org/10.1139/apnm-2014-0271.

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Eighty-two persons with multiple sclerosis wore an accelerometer as a measure of sedentary time (min/day) and completed measures of disability status (self-reported Expanded Disability Status Scale), walking performance (timed 25-foot walk and 6-min walk), and cognitive function (symbol digit modalities test). Accelerometry-measured sedentary time was significantly correlated with disability status scores (r = 0.31, p < 0.01), 6-min walk distance (r = –0.40, p < 0.01), and timed 25-foot walk performance (r = 0.35, p < 0.01), but not cognitive function performance (r = –0.12, p = 0.29).

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Fianco, Marcos, Pedro Guilherme Barrios de Souza-Dias, Fernando de Farias-Martins, Suzana Magro, Victor Mateus Prasniewski, Jéssica Ricci, Edison Zefa et Neucir Szinwelski. « Ethology of the cricket Endecous (Endecous) chape Souza-Dias & ; de Mello, 2017 (Orthoptera : Grylloidea : Phalangopsidae) I : Agonistic and reproductive behavior ». Journal of Orthoptera Research 27, n^o 2 (10 décembre 2018) : 193–201. http://dx.doi.org/10.3897/jor.27.29687.

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The mating behaviors of crickets, especially those related to agonistic encounters and oviposition, are poorly known. For example, only 10 of the 1005 valid species of Phalangopsidae have been studied to some extent. Here, we describe the reproductive behavior of Endecous (Endecous) chape, characterizing the actions involved in agonistic encounters, mating behaviors (female attraction, pair-formation, courtship, mating, and post-copulatory behavior), and oviposition. We recorded and timed agonistic, mating, and oviposition behaviors in staged trials. The male-male interactions ofE.chaperanged in aggressiveness from low intensity (only antennal interaction) to high intensity (reciprocal fights). In the mating behavior, males courted females through antennation of the females’ abdomen and cerci, followed by production of acoustic signals (with the exception of two males). Copulation occurred with females positioned above males (as is typical of Phalangopsidae), with an average elapsed time of 684.13 s, which is shorter than in other Phalangopsidae. We observed oviposition behavior only when three gravid females were placed together in an arena. Here, we contribute new knowledge of phalangopsid cricket behavior and provide useful information for understanding the evolution of reproductive behaviors. New characters described here can be used in phylogenetic analysis and for future studies about sexual selection and natural history.

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Li, Shao Feng. « A Study on Network Protocol Validation Based on Timed Automata ». Applied Mechanics and Materials 543-547 (mars 2014) : 3386–90. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.3386.

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With the increasingly complex of computer software system, traditional software engineering methods for major software development will inevitably produce a lot of mistakes and catastrophic consequences for key industry users. Experiment with software engineering methods cannot guarantee the behavior at infinity reliability and security of the state space. All this requires formal analysis and verification to the complex system. In protocol verification based on automatic machines, the automaton is used to represent the behavior of the system, the time automaton is a formal method can be well applied to the network protocol verification.

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Cornanguer, Lénaïg, Christine Largouët, Laurence Rozé et Alexandre Termier. « TAG : Learning Timed Automata from Logs ». Proceedings of the AAAI Conference on Artificial Intelligence 36, n^o 4 (28 juin 2022) : 3949–58. http://dx.doi.org/10.1609/aaai.v36i4.20311.

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Event logs are often one of the main sources of information to understand the behavior of a system. While numerous approaches have extracted partial information from event logs, in this work, we aim at inferring a global model of a system from its event logs. We consider real-time systems, which can be modeled with Timed Automata: our approach is thus a Timed Automata learner. There is a handful of related work, however, they might require a lot of parameters or produce Timed Automata that either are undeterministic or lack precision. In contrast, our proposed approach, called TAG, requires only one parameter and learns a deterministic Timed Automaton having a good tradeoff between accuracy and complexity of the automata. This allows getting an interpretable and accurate global model of the real-time system considered. Our experiments compare our approach to the related work and demonstrate its merits.

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Tvardovskii, Aleksandr Sergeevich, et Nina Vladimirovna Yevtushenko. « Deriving Homing Sequences for Finite State Machines with Timed Guards ». Modeling and Analysis of Information Systems 27, n^o 4 (20 décembre 2020) : 376–95. http://dx.doi.org/10.18255/1818-1015-2020-4-376-395.

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State identification is the well-known problem in the theory of Finite State Machines (FSM) where homing sequences (HS) are used for the identification of a current FSM state, and this fact is widely used in the area of software and hardware testing and verification. For various kinds of FSMs, such as partial, complete, deterministic, non-deterministic, there exist sufficient and necessary conditions for the existence ofpreset and adaptive HS and algorithms for their derivation. Nowadays timed aspects become very important for hardware and software systems and for this reason classical FSMs are extended by clock variables. In this work, we address the problem of checking the existence and derivation of homing sequences for FSMs with timed guards and show that the length estimation for timed homing sequence coincides with that for untimed FSM. The investigation is based on the FSM abstraction of a Timed FSM, i.e. on a classical FSM which describes behavior of corresponding TFSM and inherits some of its properties. When solving state identification problems for timed FSMs, the existing FSM abstraction is properly optimized.

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Moldakarimov, Samat, Maxim Bazhenov et Terrence J. Sejnowski. « Feedback stabilizes propagation of synchronous spiking in cortical neural networks ». Proceedings of the National Academy of Sciences 112, n^o 8 (9 février 2015) : 2545–50. http://dx.doi.org/10.1073/pnas.1500643112.

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Precisely timed action potentials related to stimuli and behavior have been observed in the cerebral cortex. However, information carried by the precise spike timing has to propagate through many cortical areas, and noise could disrupt millisecond precision during the transmission. Previous studies have demonstrated that only strong stimuli that evoke a large number of spikes with small dispersion of spike times can propagate through multilayer networks without degrading the temporal precision. Here we show that feedback projections can increase the number of spikes in spike volleys without degrading their temporal precision. Feedback also increased the range of spike volleys that can propagate through multilayer networks. Our work suggests that feedback projections could be responsible for the reliable propagation of information encoded in spike times through cortex, and thus could serve as an attentional mechanism to regulate the flow of information in the cortex. Feedback projections may also participate in generating spike synchronization that is engaged in cognitive behaviors by the same mechanisms described here for spike propagation.

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Pomponio, Laura, Marc Le Goc, Alain Anfosso et Eric Pascual. « Levels of Abstraction for Behavior Modeling in the GerHome Project ». International Journal of E-Health and Medical Communications 3, n^o 3 (juillet 2012) : 12–28. http://dx.doi.org/10.4018/jehmc.2012070102.

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Defining activity models in order to monitor human behavior in smart environments is one of the major issues at the moment of building systems of activity supervision for diagnosis, prediction and control. For the purpose of addressing this problem, this paper proposes a general theoretical approach based on the use of a Knowledge Engineering methodology and a Machine Learning process, which are funded on a general theory of dynamic process modeling, the Timed Observation Theory.

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Hwang, Chi-Pan, et Cheng-Seen Ho. « A NEW TECHNIQUE FOR BEHAVIOR AND TEMPORAL ANALYSIS OF TIMED PETRI NETS ». Journal of the Chinese Institute of Engineers 20, n^o 5 (1 septembre 1997) : 481–92. http://dx.doi.org/10.1080/02533839.1997.9741855.

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Takai, Shigemasa. « A characterization of realizable behavior in supervisory control of timed event graphs ». Automatica 33, n^o 11 (novembre 1997) : 2077–80. http://dx.doi.org/10.1016/s0005-1098(97)00121-0.

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Yan, Xu Qin, Xiao Jian Liu, Zhi Xue Wang, Xiao Bo Che, Cheng Yong Mao, Yang Li et Wei Cheng. « Towards a Component-Based Requirements Modeling for Automotive Systems ». Applied Mechanics and Materials 40-41 (novembre 2010) : 955–60. http://dx.doi.org/10.4028/www.scientific.net/amm.40-41.955.

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Requirements modeling is a critical stage in the development of ECUs (Electronic Control Unit) of automotive systems. A typical automotive system usually involves large amount of requirement items, and possesses restricted timing constraints and complicated interactions, therefore a single modeling language only does not cover the whole characteristics of a system. In this paper, we extend SaveCCM, a component model for automotive software development, with timed automata to form a modeling framework for automotive requirements. The integrated model can be used to analyze the architecture and timed behavior of an automotive system. The proposed approach takes the following advantages that: (1) It can effectively and completely express the architecture and behavior requirements of automotive systems; (2) It can describe the interactions between an ECU and its environment in terms of synchronization channels.

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Allamigeon, Xavier, Marin Boyet et Stéphane Gaubert. « Piecewise Affine Dynamical Models of Petri Nets – Application to Emergency Call Centers* ». Fundamenta Informaticae 183, n^o 3-4 (10 janvier 2022) : 169–201. http://dx.doi.org/10.3233/fi-2021-2086.

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We study timed Petri nets, with preselection and priority routing. We represent the behavior of these systems by piecewise affine dynamical systems. We use tools from the theory of nonexpansive mappings to analyze these systems. We establish an equivalence theorem between priority-free fluid timed Petri nets and semi-Markov decision processes, from which we derive the convergence to a periodic regime and the polynomial-time computability of the throughput. More generally, we develop an approach inspired by tropical geometry, characterizing the congestion phases as the cells of a polyhedral complex. We illustrate these results by a current application to the performance evaluation of emergency call centers in the Paris area. We show that priorities can lead to a paradoxical behavior: in certain regimes, the throughput of the most prioritary task may not be an increasing function of the resources.

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Longhurst, Jason K., John V. Rider, Kameron Eckard, Ryan Hammar, Franjo Vukojevic, Jillian Campbell et Merrill R. Landers. « Factors predicting fear of falling avoidance behavior in parkinsonisms ». NeuroRehabilitation 50, n^o 1 (31 janvier 2022) : 65–73. http://dx.doi.org/10.3233/nre-210267.

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BACKGROUND: Fear of falling avoidance behavior (FFAB) is common in parkinsonisms and results in potentially mitigable downstream consequences. OBJECTIVE: Determine the characteristics of individuals with parkinsonisms most associated with FFAB. METHODS: A retrospective, cross-sectional study was conducted from medical records data of 142 patients with parkinsonisms. These data included: demographics (age, sex), disease severity (Movement Disorders Society –Unified Parkinson’s Disease Rating Scale Part III (MDS-UPDRS III), years since diagnosis), fall history (number of fall injuries in previous year), and gait and balance function (five times sit to stand, MiniBESTest, Timed Up and Go (TUG), dual-task TUG, ten-meter walk test (10MWT), observed freezing of gait (FOG) (MDS-UPDRS III item 11)). RESULTS: 10MWT (p < .001) and MDS-UPDRS III item 11 (p < .014) were significantly associated with FFAB above and beyond disease severity, which also contributed significantly to the overall model (ps < .046). Fall history was not associated with FFAB. CONCLUSION: Our findings suggest that the largest portion of variability in FFAB is explained by gait velocity and FOG; however, disease severity also explains a significant portion of the variability of FFAB. Further investigation into factors predictive of FFAB and mitigation of downstream consequences, using more robust designs, is warranted.

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Chen, Shin-Guang. « Modeling and Applications on Timed Stochastic-Flow Networks ». International Journal of Reliability, Quality and Safety Engineering 22, n^o 05 (octobre 2015) : 1550023. http://dx.doi.org/10.1142/s0218539315500230.

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A stochastic-flow network (SFN) is a network whose flow has stochastic behavior or probabilistic multi-states. A timed stochastic-flow network (TSFN) is a SFN whose flow spends time to go through the network. Traditionally, the evaluation of network reliability does not consider time consumption for the flow to get through the network. However, there are lots of daily-life networks which can be regarded as TSFNs, such as the transportation network, the production network, etc. Their flow spends time to get through the network, and they are not yet explored in the literature. This paper proposes approaches to evaluate the reliability of such networks. Some numerical examples are discussed to illustrate the proposed method.

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POERNOMO, IMAN, HEINZ SCHMIDT et JANE JAYAPUTERA. « VERIFICATION AND PREDICTION OF TIMED PROBABILISTIC PROPERTIES OVER THE DMTF CIM ». International Journal of Cooperative Information Systems 15, n^o 04 (décembre 2006) : 633–58. http://dx.doi.org/10.1142/s0218843006001517.

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Understanding nonfunctional aspects of system behavior is an essential component of practical software development and maintenance. Many nonfunctional system properties, such as reliability and availability, involve time and probabilities. In this paper, we present a framework for runtime verification and prediction of timed and probabilistic nonfunctional properties of component-based architectures, built using the Meta-Object Facility and the Distributed Management Task Force's Common Information Model (CIM) standard. We describe a Microsoft .NET-based implementation of our framework. We define a language for describing timed probabilistic behavior based on Probabilistic Computational Tree Logic (PCTL). We provide a formal semantics for this language in terms of observed application execution traces. The semantics is interesting in that it permits checking of required timing behavior both over the overall average of traces and also over local "trends" in traces. The latter aspect of the semantics is achieved by incorporating exponential smoothing prediction techniques into the truth function for statements of our language. The semantics is generic over the aspects of an application that are represented by states and state transitions. This enables the language to be used to describe a wide range of nonfunctional properties for runtime verification and prediction purposes. We explain how statements of our language are used to define precise contracts for system monitoring, through relating the semantics to an extended CIM monitoring infrastructure.

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Liu, Qing, Daiyong Cui, Guanglei Cong, Jinliang Ma, Jie Yu, Chuanliang Ji et Shenming Zeng. « Timed Artificial Insemination by Combining Estrous Behavior Observation With Deslorelin Treatment in Jennies ». Journal of Equine Veterinary Science 95 (décembre 2020) : 103279. http://dx.doi.org/10.1016/j.jevs.2020.103279.

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COMINI, MARCO, LAURA TITOLO et ALICIA VILLANUEVA. « Abstract diagnosis for timed concurrent constraint programs ». Theory and Practice of Logic Programming 11, n^o 4-5 (juillet 2011) : 487–502. http://dx.doi.org/10.1017/s1471068411000135.

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AbstractThe timed concurrent constraint language (tccp in short) is a concurrent logic language based on the simple but powerful concurrent constraint paradigm of Saraswat. In this paradigm, the notion of store-as-value is replaced by the notion of store-as-constraint, which introduces some differences w.r.t. other approaches to concurrency. In this paper, we provide a general framework for the debugging of tccp programs. To this end, we first present a new compact, bottom-up semantics for the language that is well suited for debugging and verification purposes in the context of reactive systems. We also provide an abstract semantics that allows us to effectively implement debugging algorithms based on abstract interpretation. Given a tccp program and a behavior specification, our debugging approach automatically detects whether the program satisfies the specification. This differs from other semi-automatic approaches to debugging and avoids the need to provide symptoms in advance. We show the efficacy of our approach by introducing two illustrative examples. We choose a specific abstract domain and show how we can detect that a program is erroneous.

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Marshakov, D. V. « Modeling of the processes of extracting rules from Neural Network components with Petri nets ». Journal of Physics : Conference Series 2131, n^o 2 (1 décembre 2021) : 022133. http://dx.doi.org/10.1088/1742-6596/2131/2/022133.

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Abstract The paper deals with the use of extended Petri nets in modeling the processes of extracting rules from neural network components. The mathematical model for extracting rules from neural network components based on a modified timed Petri net is constructed, followed by an analysis of its dynamic behavior based on a timed reachability graph, which is a set of all its states that can be reached when a finite number of transitions are fired. The proposed model allows us to move from the initial detailed structure to its simplified description, which preserves the possibility of obtaining information about the structure and dynamic behavior of the neural network system. The proposed approach can be used in the synthesis of cognitive systems with a neural network organization to provide computational support for the functions of forming, learning, and correcting cognitive networks that display neural network models.

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Landers, Merrill R., Sarrie Oscar, Jessica Sasaoka et Kyle Vaughn. « Balance Confidence and Fear of Falling Avoidance Behavior Are Most Predictive of Falling in Older Adults : Prospective Analysis ». Physical Therapy 96, n^o 4 (1 avril 2016) : 433–42. http://dx.doi.org/10.2522/ptj.20150184.

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BackgroundEvidence suggests that there are several fall predictors in the elderly population, including previous fall history and balance impairment. To date, however, the role of psychological factors has not yet been thoroughly vetted in conjunction with physical factors as predictors of future falls.ObjectiveThe purpose of this study was to determine which measures, physical and psychological, are most predictive of falling in older adults.DesignThis was a prospective cohort study.MethodsSixty-four participants (mean age=72.2 years, SD=7.2; 40 women, 24 men) with and without pathology (25 healthy, 17 with Parkinson disease, 11 with cerebrovascular accident, 6 with diabetes, and 5 with a cardiovascular diagnosis) participated. Participants reported fall history and completed physical-based measures (ie, Berg Balance Scale, Dynamic Gait Index, self-selected gait speed, Timed “Up & Go” Test, Sensory Organization Test) and psychological-based measures (ie, Fear of Falling Avoidance Behavior Questionnaire, Falls Efficacy Scale, Activities-specific Balance Confidence Scale). Contact was made 1 year later to determine falls during the subsequent year (8 participants lost at follow-up).ResultsUsing multiple regression, fall history, pathology, and all measures were entered as predictor candidates. Three variables were included in the final model, explaining 49.2% of the variance: Activities-specific Balance Confidence Scale (38.7% of the variance), Fear of Falling Avoidance Behavior Questionnaire (5.6% additional variance), and Timed “Up & Go” Test (4.9% additional variance).LimitationsFalls were based on participant recall rather than a diary.ConclusionsBalance confidence was the best predictor of falling, followed by fear of falling avoidance behavior, and the Timed “Up & Go” Test. Fall history, presence of pathology, and physical tests did not predict falling. These findings suggest that participants may have had a better sense of their fall risk than with a test that provides a snapshot of their balance.

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Balcı, Fuat. « Interval Timing, Dopamine, and Motivation ». Timing & ; Time Perception 2, n^o 3 (2014) : 379–410. http://dx.doi.org/10.1163/22134468-00002035.

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The dopamine clock hypothesis suggests that the dopamine level determines the speed of the hypothetical internal clock. However, dopaminergic function has also been implicated for motivation and thus the effect of dopaminergic manipulations on timing behavior might also be independently mediated by altered motivational state. Studies that investigated the effect of motivational manipulations on peak responding are reviewed in this paper. The majority of these studies show that a higher reward magnitude leads to a leftward shift, whereas reward devaluation leads to a rightward shift in the initiation of timed anticipatory behavior, typically in the absence of an effect on the timing of response termination. Similar behavioral effects are also present in a number of studies that investigated the effect of dopamine agonists and dopamine-related genetic factors on peak responding. These results can be readily accounted for by independent modulation of decision-thresholds for the initiation and termination of timed responding.

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Muñoz, Doyra Mariela, Antonio Correcher, Emilio García et Francisco Morant. « Stochastic DES Fault Diagnosis with Coloured Interpreted Petri Nets ». Mathematical Problems in Engineering 2015 (2015) : 1–13. http://dx.doi.org/10.1155/2015/303107.

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This proposal presents an online method to detect and isolate faults in stochastic discrete event systems without previous model. A coloured timed interpreted Petri Net generates the normal behavior language after an identification stage. The next step is fault detection that is carried out by comparing the observed event sequences with the expected event sequences. Once a new fault is detected, a learning algorithm changes the structure of the diagnoser, so it is able to learn new fault languages. Moreover, the diagnoser includes timed events to represent and diagnose stochastic languages. Finally, this paper proposes a detectability condition for stochastic DES and the sufficient and necessary conditions are proved.

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FALASCHI, MORENO, et ALICIA VILLANUEVA. « Automatic verification of timed concurrent constraint programs ». Theory and Practice of Logic Programming 6, n^o 3 (mai 2006) : 265–300. http://dx.doi.org/10.1017/s1471068406002675.

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The language Timed Concurrent Constraint (tccp) is the extension over time of the Concurrent Constraint Programming (cc) paradigm that allows us to specify concurrent systems where timing is critical, for example reactive systems. Systems which may have an infinite number of states can be specified in tccp. Model checking is a technique which is able to verify finite-state systems with a huge number of states in an automatic way. In the last years several studies have investigated how to extend model checking techniques to systems with an infinite number of states. In this paper we propose an approach which exploits the computation model of tccp. Constraint based computations allow us to define a methodology for applying a model checking algorithm to (a class of) infinite-state systems. We extend the classical algorithm of model checking for LTL to a specific logic defined for the verification of tccp and to the tccp Structure which we define in this work for modeling the program behavior. We define a restriction on the time in order to get a finite model and then we develop some illustrative examples. To the best of our knowledge this is the first approach that defines a model checking methodology for tccp.

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Jacobson, Lisa A., et E. Mark Mahone. « Sluggish Cognitive Tempo Predicts Academic Fluency, Beyond Contributions of Core Academic Skills, Attention, and Motor Speed ». Journal of Attention Disorders 23, n^o 14 (20 mai 2018) : 1703–10. http://dx.doi.org/10.1177/1087054718776468.

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Objective: Sluggish Cognitive Tempo (SCT) is a distinct behavioral phenotype characterized by such symptoms as being slow to complete tasks, appearing drowsy or sleepy, and lacking initiative. Subcomponents of SCT appear differentially associated with inattention symptoms and child outcomes. Much of the work in this area has examined associations between SCT symptoms and ratings of behavior; few studies have examined associations with child performance. Method: We examined associations between SCT and timed reading and math skills in 247 referred youth ( M age = 11.55, range = 6-20; 67.6% male), controlling for the untimed academic skills, inattention, and graphomotor speed. Results: SCT consistently predicted timed academic fluency, after controlling for other component skills, for both reading (SCT Δ R2 = .039, p = .001) and math (Δ R2 = .049, p = .001). Conclusion: Results provide initial evidence for the unique association of SCT with timed academic performance. Understanding associations of SCT with actual child performance may allow for greater specificity in targeting interventions to address speed of performance.

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Tóth, Tamás, et István Majzik. « Formal Verification of Real-Time Systems with Data Processing ». Periodica Polytechnica Electrical Engineering and Computer Science 61, n^o 2 (23 mai 2017) : 166. http://dx.doi.org/10.3311/ppee.9766.

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The behavior of practical safety critical systems often combines real-time behavior with structured data flow. To ensure correctness of such systems, both aspects have to be modeled and formally verified. Time related behavior can be efficiently modeled and analyzed in terms of timed automata. At the same time, program verification techniques like abstract interpretation and software model checking can efficiently handle data flow. In this paper, we describe a simple formalism that represents both aspects of such systems in a uniform and explicit way, thus enables the combination of formal analysis methods for real-time systems and software using standard techniques.

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Cadogan, Beresford L., et Roger D. Scharbach. « EFFICACY OF FORAY 48B (BACILLUS THURINGIENSIS BERLINER) APPLICATIONS AGAINST THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEMENS) (LEPIDOPTERA : TORTRICIDAE), TIMED FOR PHENOLOGICAL DEVELOPMENT OF BALSAM FIR AND BLACK SPRUCE ». Canadian Entomologist 125, n^o 3 (juin 1993) : 479–88. http://dx.doi.org/10.4039/ent125479-3.

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AbstractThe insecticide Foray 48B (Bacillus thuringiensis var. kurstaki Berliner) was applied undiluted at 30 BIU per ha to control spruce budworm, Choristoneura fumiferana (Clem.), in a mixed boreal forest stand of balsam fir, Abies balsamea (L.) Mill., and black spruce, Picea mariana (Mill.) B.S.P. When the treatment was timed to coincide with the early flushing of balsam fir shoots, the corrected budworm population reductions were 74 and 52% on balsam fir and black spruce, respectively. This treatment resulted in 19 and 8% defoliation on the two respective species. When the insecticide application was timed later to coincide with the late flushing of black spruce shoots the corrected population reductions were 93% on balsam fir and 72% on black spruce. Defoliation of the two species was 29 and 10% respectively, following this treatment. Larval survival on both species after the spray timed for black spruce (0.8 and 2.2 larvae per 45-cm branch on balsam fir and black spruce, respectively) was significantly less (P = 0.05) than that observed after the spray timed for balsam fir (4.6 and 4.2 larvae per 45-cm branch on the respective host species).The data indicate that the spray timed to correspond with the flushing of black spruce was generally more efficacious than the spray timed to impact on newly flushed balsam fir; nevertheless, the results raise the question as to how B. thuringiensis insecticides impact on early-instar budworm larvae when there is no preferred current year foliage on which the insects can feed.

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FRIBOURG, LAURENT, et ULRICH KÜHNE. « PARAMETRIC VERIFICATION AND TEST COVERAGE FOR HYBRID AUTOMATA USING THE INVERSE METHOD ». International Journal of Foundations of Computer Science 24, n^o 02 (février 2013) : 233–49. http://dx.doi.org/10.1142/s0129054113400091.

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Hybrid systems combine continuous and discrete behavior. Hybrid Automata are a powerful formalism for the modeling and verification of such systems. A common problem in hybrid system verification is the good parameters problem, which consists in identifying a set of parameter valuations which guarantee a certain behavior of a system. Recently, a method has been presented for attacking this problem for Timed Automata. In this paper, we show the extension of this methodology for hybrid automata with linear and affine dynamics. The method is demonstrated with a hybrid system benchmark from the literature.

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Lee, Stephen M., Alicia Peltsch, Maureen Kilmade, Donald C. Brien, Brian C. Coe, Ingrid S. Johnsrude et Douglas P. Munoz. « Neural Correlates of Predictive Saccades ». Journal of Cognitive Neuroscience 28, n^o 8 (août 2016) : 1210–27. http://dx.doi.org/10.1162/jocn_a_00968.

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Every day we generate motor responses that are timed with external cues. This phenomenon of sensorimotor synchronization has been simplified and studied extensively using finger tapping sequences that are executed in synchrony with auditory stimuli. The predictive saccade paradigm closely resembles the finger tapping task. In this paradigm, participants follow a visual target that “steps” between two fixed locations on a visual screen at predictable ISIs. Eventually, the time from target appearance to saccade initiation (i.e., saccadic RT) becomes predictive with values nearing 0 msec. Unlike the finger tapping literature, neural control of predictive behavior described within the eye movement literature has not been well established and is inconsistent, especially between neuroimaging and patient lesion studies. To resolve these discrepancies, we used fMRI to investigate the neural correlates of predictive saccades by contrasting brain areas involved with behavior generated from the predictive saccade task with behavior generated from a reactive saccade task (saccades are generated toward targets that are unpredictably timed). We observed striking differences in neural recruitment between reactive and predictive conditions: Reactive saccades recruited oculomotor structures, as predicted, whereas predictive saccades recruited brain structures that support timing in motor responses, such as the crus I of the cerebellum, and structures commonly associated with the default mode network. Therefore, our results were more consistent with those found in the finger tapping literature.

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Larsen, Caroline M., et David R. Grattan. « Prolactin-Induced Mitogenesis in the Subventricular Zone of the Maternal Brain during Early Pregnancy Is Essential for Normal Postpartum Behavioral Responses in the Mother ». Endocrinology 151, n^o 8 (19 mai 2010) : 3805–14. http://dx.doi.org/10.1210/en.2009-1385.

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High prolactin during pregnancy, which is essential for normal postpartum maternal behavior, increases neurogenesis in the subventricular zone of the lateral ventricle (SVZ) of the maternal brain. Because SVZ mitogenesis generates new olfactory neurons and may contribute to perception of novel odorants, we hypothesized that the prolactin-induced increase in SVZ mitogenesis during pregnancy might be important for normal maternal interactions with pups. To investigate this hypothesis, prolactin secretion was suppressed for 3 d early in pregnancy in mice, using a carefully timed dose of bromocriptine. The bromocriptine-induced reduction in prolactin prevented the normal increase in generation of neural progenitors in the SVZ of the maternal brain. Another group of bromocriptine-treated animals were allowed to continue their pregnancy until term, and then maternal behaviors were evaluated postpartum. Low prolactin during early pregnancy, and the consequent suppression of mitogenesis in the SVZ of the maternal brain, was subsequently followed by increased postpartum anxiety and markedly impaired maternal behavior. In another group of pregnant females, injections of the mitotic inhibitor methylazoxymethanol to specifically suppress neurogenesis in the mother during early pregnancy without affecting prolactin secretion also caused postpartum anxiety and impaired maternal behavior. These data demonstrate that prolactin-induced increase in generation of neural progenitors in the SVZ of the maternal brain during early pregnancy is required for normal expression of postpartum maternal behaviors.

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Sharp, N. C. C. « Timed running speed of a cheetah (Acinonyx jubatus) ». Journal of Zoology 241, n^o 3 (mars 1997) : 493–94. http://dx.doi.org/10.1111/j.1469-7998.1997.tb04840.x.

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Williams, Douglas A., Carla Lawson, Rachel Cook, Amber A. Mather et Kenneth W. Johns. « Timed excitatory conditioning under zero and negative contingencies. » Journal of Experimental Psychology : Animal Behavior Processes 34, n^o 1 (2008) : 94–105. http://dx.doi.org/10.1037/0097-7403.34.1.94.

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Zhang, Hai Bin, et Li Ya Yang. « Model Checking Multirate Hybrid Systems with Dense Timed Interval Temporal Logic ». Applied Mechanics and Materials 198-199 (septembre 2012) : 889–93. http://dx.doi.org/10.4028/www.scientific.net/amm.198-199.889.

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This paper investigates the model checking issue of multirate hybrid systems. To this end, multirate automata are used to represent the possible behavior of multirate hybrid systems, and a dense timed interval temporal logic (DTITL) is defined to describe the desirable property. To check whether a multirate automaton satisfies a DTITL formula, a corresponding region automaton and a propositional interval temporal logic (PITL) formula are constructed. After each vertex of the region automaton being labeled with propositions appearing in the corresponding PITL formula, the model checking problem for mutirate hybrid systems is reduced to the same issue for PITL, which can be solved readily.

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Thexton, A. J., A. W. Crompton et R. Z. German. « EMG activity in hyoid muscles during pig suckling ». Journal of Applied Physiology 112, n^o 9 (1 mai 2012) : 1512–19. http://dx.doi.org/10.1152/japplphysiol.00450.2011.

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Infant suckling is a complex behavior that includes cycles of rhythmic sucking as well as intermittent swallows. This behavior has three cycle types: 1) suck cycles, when milk is obtained from the teat and moved posteriorly into the valleculae in the oropharynx; 2) suck-swallow cycles, which include both a rhythmic suck and a pharyngeal swallow, where milk is moved out of the valleculae, past the larynx, and into the esophagus; and 3) postswallow suck cycles, immediately following the suck-swallow cycles. Because muscles controlling these behaviors are active in all three types of cycles, we tested the hypothesis that different patterns of electromyographic (EMG) activity in the mylohyoid, hyoglossus, stylohyoid, and thyrohyoid muscles of the pig characterized each cycle type. Anterior mylohyoid EMG activity occurred regularly in every cycle and was used as a cycle marker. Thyrohyoid activity, indicating the pharyngeal swallow, was immediately preceded by increased stylohyoid and hyoglossus activity; it divided the suck-swallow cycle into two phases. Timed from the onset of the suck-swallow cycle, the first phase had a relatively fixed duration while the duration of the second phase, timed from the thyrohyoid, varied directly with cycle duration. In short-duration cycles, the second phase could have a zero duration so that thyrohyoid activity extended into the postswallow cycle. In such cycles, all swallowing activity that occurred after the thyrohyoid EMG and was associated with bolus passage through the pharynx fell into the postswallow cycle. These data suggest that while the activity of some muscles, innervated by trigeminal and cervical plexus nerves, may be time locked to the cycle onset in swallowing, the cycle period itself is not. The postswallow cycle consequently contains variable amounts of pharyngeal swallowing EMG activity. The results exemplify the complexity of the relationship between rhythmic sucking and the swallow.

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