Showing papers by "Thales (Netherlands) published in 2019"

Optimal Particle-Filter-Based Detector

Abstract: In this letter, we propose and prove the asymptotic optimality of a particle-filter-based detection scheme. The detection method can be used in a general nonlinear/non-Gaussian signal detection problem. The proposed detection mechanism is based on the likelihood ratio (LR) and thus optimal in the Neyman–Pearson sense, but we approximate the LR based on a particle filter (PF). We show the asymptotic optimality by proving that the PF-based approximation of the LR converges to the true LR as the number of particles increases to infinity. We also discuss the practical and operational implications of the result, the main one being that it is optimal in the sense that no other processing and detection mechanism can have higher probability of detection, while having the same or lower false alarm rate.

Heat pipe array for planar cooling of rotating radar systems

Abstract: This paper presents a planar cooling strategy for rotating radar systems using heat pipe technology. The proposed design uses six 1 m long heat pipes in parallel oriented in an evaporator-down modus at an elevation angle of 85 deg. An analytical model based on conventional heat pipe limits is used to predict the performance taking into account both gravitational and centrifugal forces. The heat pipe array is mounted on a rotating platform of which both the mounting angle w.r.t. the rotational arm and rotational speed can be varied. The radial distance w.r.t. the rotational axis was set at 0.5 m. The setup was tested in an environmental chamber to simulate higher ambient temperatures as well. Moreover, measurements were conducted by varying the heat sink airflow rates. The performance was determined by the temperature gradient across the planar structure. Successful heat pipe operation and experimental performances were determined for a number of application parameters. At higher rotational speeds, the influence of centrifugal forces that may assist or hinder the working fluid circulation became discernible. For higher rotational frequencies, the mounting angle proved to be of (minor) influence on the performance in agreement with the developed model. The current design was validated for effective planar cooling of a rotating radar system for planar heat loads up to 1000 W. Temperature gradients across the planar structure remain below critical limits and overall thermal resistances from planar to ambient air conditions of 0.040 K/W and below were observed.

Devilish Dilemma Games: Narrative Game Engine and Accompanying Authoring Tool.

Abstract: In this paper we will focus on a narrative game engine and accompanying authoring tool that allows for easy development of game scenarios, including in-game and summative feedback in terms of key performance indicators and decision-making styles. Using our model driven game engine, we co-developed numerous games together with several modelling and simulation experts from various domains. The resulting single player turn-taking games are offered as a game service via on-line accessible learning management systems, and currently used in a variety of leadership training programs making trainees aware of their natural decision-making behaviors.

Mixed-Mode S-Parameter Measurements for Determination of Cable Coupling

Abstract: Single-ended S-parameters are used to quantify electromagnetic coupling, or crosstalk, between cables. The use of this measurement technique is demonstrated on a case where crosstalk occurs between two wire pairs above ground. S-parameter measurements involve no elements that introduce frequency restrictions, such as baluns or current clamps. Moreover, by measuring or simulating all combinations of S-parameters and converting these to mixed-mode S-parameters, not only differential-mode (DM), but also common-mode (CM) and mode-conversion S-parameters are obtained. When only the coupling between a specific combination of cables is desired, it is sufficient to measure only a small subset of all S-parameters. Finally, the relation between crosstalk as defined in the standards and the obtained S-parameters is discussed.

Job Interview Game for High Functioning Autist.

Abstract: We report on a job interview simulation game developed as part of the BRAINTRAIN project funded by the EU. The on-line accessible single-player 2D narrative game is adaptive to the trainees’ (a) answering responses to questions by a virtual interviewer, (b) point of gaze towards the interviewer, and (c) his/her stress levels. Adaptiveness was realized by changing the game world in terms of more or less abstract interviewing questions, increasing or decreasing visual and audio clutter in the game interface. The game is intended to be an intervention instrument aiming to improve social communication and interaction skills. The target group are high functioning Autism Spectrum Disorder (ASD) adults. To test the feasibility of such a tool, we report on findings from a market study in terms of a SWOT analysis, and we show the results from a user study in terms of hypothesized effects on social skills improvements.

Towards Trustworthy Man-Machine Synchronization.

Abstract: Hyperscanning is a method by which multiple individuals can interact with one another while their brains are simultaneously scanned. Interpersonal brain activity synchronization has found to be indicative for levels of collaboration, trust, coordination and leadership among team members. Here it is suggested that systems that team with humans need to provoke specific responses as humans do to synchronize. Entities ‘in sync’ perform better. Therefore, understanding social interactions between humans in terms of synchronization may be the prerequisite for developing and enhancing true trustworthy man-machine teaming.