Technical Note: Development of a generalized source model for flux estimation in nuclear reactors

Abstract. Inverse modeling methods are now commonly used for estimating surface fluxes of carbon dioxide, using atmospheric mass fraction measurements combined with a numerical atmospheric transport model. The geostatistical approach to flux estimation takes advantage of the spatial and/or temporal correlation in fluxes and does not require prior flux estimates. In this work, a geostatistical implementation of a fixed-lag Kalman smoother is developed to improve the computational efficiency of the inverse problem. This method makes it feasible to perform multi-year inversions, at fine resolutions, and with large amounts of data. The new method is applied to the recovery of global gridscale carbon dioxide fluxes for 1997 to 2001 using pseudodata representative of a subset of the NOAA-ESRL Cooperative Air Sampling Network.

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Novel Model-Based approach for instrumentation and control of nuclear reactors

EPJ Web of Conferences ◽

10.1051/epjconf/202125305003 ◽

2021 ◽

Vol 253 ◽

pp. 05003

Author(s):

Bassem Ouni ◽

Christophe Aussagues ◽

Saadia Dhouib ◽

Chokri Mraidha

Keyword(s):

Nuclear Reactors ◽

System Development ◽

Source Model ◽

System Specification ◽

Levels Of Abstraction ◽

Model Based ◽

Digital Instrumentation ◽

High Level ◽

And Control ◽

Different Levels

Technological platforms dedicated for digital instrumentation and control of nuclear reactors are quite complex in terms of functionalities and devices. Hence, the design of these platforms requires high-level abstraction layers able to reduce the complexity, to rise the automation and to check the consistency between different development stages. The development of such systems is a challenging task that requires modeling of various components at different levels of abstraction and viewpoints, notably functional, hardware and software levels. In this paper, a new system engineering methodology is proposed to provide high-level models of different components and inter/intra-communication between them. These models are used for system specification, architecture design, performance evaluation or verification and validation. This approach focuses on the internal behavior of different components at different levels of abstraction in order to enable the interoperability of these components and to enhance cooperation between different stakeholders of the development process. An experimental setup has been carried out to validate this approach by customizing an open source model based engineering tool, Eclipse Papyrus, towards a significant reduction of system development cost in terms of engineering resources and equipment devices.

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New AAC Access Strategy for Gesture Tracking: A Technical Note

Perspectives on Augmentative and Alternative Communication ◽

10.1044/aac21.1.11 ◽

2012 ◽

Vol 21 (1) ◽

pp. 11-16 ◽

Cited By ~ 1

Author(s):

Susan Fager ◽

Tom Jakobs ◽

David Beukelman ◽

Tricia Ternus ◽

Haylee Schley

Keyword(s):

Augmentative And Alternative Communication ◽

Technical Note ◽

Head Tracking ◽

Alternative Communication ◽

Access Methods ◽

Cord Injury ◽

Physical Limitations ◽

Gesture Tracking ◽

Communication Needs ◽

Tracking Device

Abstract This article summarizes the design and evaluation of a new augmentative and alternative communication (AAC) interface strategy for people with complex communication needs and severe physical limitations. This strategy combines typing, gesture recognition, and word prediction to input text into AAC software using touchscreen or head movement tracking access methods. Eight individuals with movement limitations due to spinal cord injury, amyotrophic lateral sclerosis, polio, and Guillain Barre syndrome participated in the evaluation of the prototype technology using a head-tracking device. Fourteen typical individuals participated in the evaluation of the prototype using a touchscreen.

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