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Yang J.,ISIR | Kan K.,ISIR | Tanimura K.,ISIR | Yoshida Y.,ISIR | Urakawa J.,High Energy Accelerator Research Organization
IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference | Year: 2016

An ultrafast detection technique on 100 fs time scales over sub-nanometer (even atomic) spatial dimensions has long been a goal for the scientists to reveal and understand the ultrafast structural-change induced dynamics in materials. In this paper, the generation of femtosecond electron pulses using the RF gun and the first prototype of femtosecond time-resolved relativistic-energy ultrafast electron microscopy (UEM) are reported. Finally, both relativistic-energy electron diffraction and image measurements in the UEM prototype are presented. Copyright © 2016 CC-BY-3.0 and by the respective authors.

Kuriki M.,HU AdSM | Seimiya Y.,HU AdSM | Seimiya Y.,High Energy Accelerator Research Organization | Kato R.,ISIR | And 6 more authors.
6th International Particle Accelerator Conference, IPAC 2015 | Year: 2015

FEL is one of the ideal radiation source over the wide range of wavelength region with a high brightness and a high coherence. Many methods to improve FEL gain and quality have been proposed by introducing an active modulation on the bunch charge distribution. The transverse-longitudinal phase-space rotation is one of the promising method to realize the density modulation as the micro-bunch structure. Initially, a beam density modulation in the transverse direction made by mechanical slits, is properly transformed into the density modulation in the longitudinal direction by the phasespace rotation. The micro-bunch structure made with this method has a large tunability by changing the slit geometry, the beam line design, and the beam dynamics tuning. For FEL, energy chirp made by the emittance exchange should be properly corrected. Simulation results and possible applications are discussed. Copyright © 2015 CC-BY-3.0 and by the respective authors.

Pandey A.K.,A Laboratory | Gelin R.,A Laboratory | Alami R.,Hoffmann-La Roche | Viry R.,Hoffmann-La Roche | And 11 more authors.
CEUR Workshop Proceedings | Year: 2014

For a socially intelligent robot, different levels of situation assessment are required, ranging from basic processing of sensor input to high-level analysis of semantics and intention. However, the attempt to combine them all prompts new research challenges and the need of a coherent framework and architecture. This paper presents the situation assessment aspect of Romeo2, a unique project aiming to bring multi-modal and multi-layered perception on a single system and targeting for a unified theoretical and functional framework for a robot companion for everyday life. It also discusses some of the innovation potentials, which the combination of these various perception abilities adds into the robot's socio-cognitive capabilities. © 2014, International Workshop on Artificial Intelligence and Cognition.

Yokoyama Y.,RISE | Aoki T.,RISE | Sakaue K.,RISE | Suzuki T.,RISE | And 8 more authors.
IPAC 2010 - 1st International Particle Accelerator Conference | Year: 2010

At Waseda University, we have been studying a high quality electron beam generation and its application experiments with Cs-Te photocathode RF-Gun. We have already succeeded in generating a stable high-charged single-bunch electron beam. To generate more intense electron beam, we designed a multi-bunch electron linac and developed the multi-pulse UV laser which irradiates to the cathode. The target values of the number of electron bunch and bunch charges are 100 bunches/train and 800pC/bunch, respectively. In addition, we adopted the method of the amplitude modulation of the incident RF pulse to the S-band klystron in order to compensate the energy difference in each bunch because of the slow rise time of acceleration voltage in cavity and beam loading effect in the accelerating structure.

Pasqui V.,ISIR | Saint-Bauzel L.,ISIR | Zong C.,ISIR | Clady X.,ISIR | And 11 more authors.
IRBM | Year: 2012

This paper aims to present the MIRAS project: a multimodal interactive robot developed to provide assistance in strolling for people suffering from locomotion troubles. The first part of this paper summarizes goals and expected impacts of the project. Each work package is then detailed: description of use-cases and associated multimodal functions, conception and realization of the robot, security analysis and clinical validation. First results of user tests are analyzed to focus on users and developers feedback. Before concluding the paper, a short discussion about interests and problematic of the study is exposed. © 2012 Elsevier Masson SAS. All rights reserved.

Reuillon R.,13 rue du Four | Schmitt C.,13 rue du Four | De Aldama R.,ISC PIF | Mouret J.-B.,ISIR
JASSS | Year: 2015

Models of social systems generally contain free parameters that cannot be evaluated directly from data. A calibration phase is therefore necessary to assess the capacity of the model to produce the expected dynamics. However, despite the high computational cost of this calibration it doesn't produce a global picture of the relationship between the parameter space and the behaviour space of the model. The Calibration Profile (CP) algorithm is an innovative method extending the concept of automated calibration processes. It computes a profile that depicts the effect of each single parameter on the model behaviour, independently from the others. A 2-dimensional graph is thus produced exposing the impact of the parameter under study on the capacity of the model to produce expected dynamics. The first part of this paper is devoted to the formal description of the CP algorithm. In the second part,we apply it to an agent based geographical model (SimpopLocal). The analysis of the results brings to light novel insights on the model. © 2015 JASSS.

Hosaka Y.,RISE | Betto R.,RISE | Fujita A.,RISE | Sakaue K.,RISE | And 4 more authors.
IPAC 2010 - 1st International Particle Accelerator Conference | Year: 2010

We have been studying a pump-probe pulse radiolysis as an application of the S-band photo cathode RF-Gun. Pump-probe spectroscopy is well-known method of pulse radiolysis measurement. We had used 5MeV electron beam obtained from the photo cathode RF-Gun as a pump beam, and used the white light emitted from Xe flash lamp or generated by self-phase modulation in the water cell as a probe light. However, the white probe light with high intensity, good stability and broad spectrum is a key issue for pump-probe pulse radiolysis. Supercontinuum light with photonic crystal fiber (PCF) is a new technique of white light generation. Short pulse laser through PCF spreads its spectrum by nonlinear optical effect. Supercontinuum light has very continuous spectrum, and it is studied for various applications recently. For applying supercontinuum light as a probe of pulse radiolysis experiment, we have generated a supercontinuum radiation with 7 picoseconds pulse width IR (1064nm) laser and PCF, and measured its properties. The experimental results of supercontinuum generation and design of a supercontinuum based pulse radiolysis system will be presented.

Chau A.,Free University of Colombia | Regnier S.,ISIR | Delchambre A.,Free University of Colombia | Lambert P.,Free University of Colombia
Journal of Adhesion Science and Technology | Year: 2010

Adhesion issues are present in many disciplines such as, for example, surface science, microrobotics or MEMS design. Within this framework, this paper presents a study on capillary forces due to capillary condensation. A simulation tool had already been presented using Surface Evolver and Matlab to compute the shape of a meniscus in accordance with the Kelvin equation and contact angles. The numerical results of this simulation complied well with literature results. One very important result is the ability to compute the evolution of the capillary force depending on the tilt angle of the gripper with respect to the object. The main contribution of this new paper is a test bench and the related experimental results which validate these numerical results. We present here new experimental results illustrating the role of humidity and tilt angle in capillary forces at the nanoscale. © 2010 Koninklijke Brill NV, Leiden.

Ollion C.,ISIR | Doncieux S.,ISIR
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

To survive in its environment, an animat must have a behavior that is not too disturbed by noise or any other distractor. Its behavior is supposed to be relatively unchanged when tested on similar situations. Evolving controllers that are robust and generalize well over similar contexts remains a challenge for several reasons. One of them comes from the evaluation: how to check a controller for such properties? The fitness may evaluate a distance towards a behavior known to be robust, but such an example is not always available. An alternative is to test the behavior in multiple conditions, actually as many as possible, to avoid overfitting, but this significantly slows down the search process. This issue is expected to become even more critical when evolving behaviors of increasing complexity. To tackle this issue, we propose to formulate it as a problem of behavioral consistency in different contexts. We then propose a fitness objective aimed at explicitly rewarding behavioral consistency. Its principle is to define different sets of contexts and compare the evolved system behavior on each of them. The fitness function thus defined aims at rewarding individuals that exhibit the expected consistency. We apply it to the evolution of two simple computational neuroscience models. © 2012 Springer-Verlag.

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