Bio-Optical Sensors on Argo Floats

The general objective of the IOCCG BIO-Argo working group is to elaborate recommendations for establishing a framework for the future development of a cost-effective, bio-optical float network corresponding to the needs and expectations of the scientific community. In this context, our recommendations will necessarily be broad; they range from the identification of key bio-optical measurements to be implemented on floats, to the real-time management of the data flux resulting from the deployment of a "fleet of floats". Each chapter of this report is dedicated to an essential brick leading towards the goal of implementing a bio-optical profiling float network. The following topics are discussed in the Chapters listed below: - Chapter 2 reviews the scientific objectives that could be tackled through the development of such networks, by allowing some of the gaps in the present spatio-temporal resolution of bio-optical variables to be progressively filled. - Chapter 3 identifies the optical and bio-optical properties that are now amenable to remote and autonomous measurement through the use of optical sensors mounted on floats. - Chapter 4 addresses the question of sensor requirements, in particular with respect to measurements performed from floats. - Chapter 5 proposes and argues for the development of dedicated float missions corresponding to specific scientific objectives and relying on specific optical sensor suites, as well as on specific modes of float operation. - Chapter 6 identifies technological issues that need to be addressed for the various bio-optical float missions to become even more cost-effective. - Chapter 7 covers all aspects of data treatment ranging from the development of various quality control procedures (from real-time to delayed mode) to the architecture required for favoring easy access to data. - Chapter 8 reviews the necessary steps and experience required before the operational implementation of different types of float networks can become a reality.JRC.H.5-Land Resources Managemen

Ocean observations in support of studies and forecasts of tropical and extratropical cyclones

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Domingues, R., Kuwano-Yoshida, A., Chardon-Maldonado, P., Todd, R. E., Halliwell, G., Kim, H., Lin, I., Sato, K., Narazaki, T., Shay, L. K., Miles, T., Glenn, S., Zhang, J. A., Jayne, S. R., Centurioni, L., Le Henaff, M., Foltz, G. R., Bringas, F., Ali, M. M., DiMarco, S. F., Hosoda, S., Fukuoka, T., LaCour, B., Mehra, A., Sanabia, E. R., Gyakum, J. R., Dong, J., Knaff, J. A., & Goni, G. Ocean observations in support of studies and forecasts of tropical and extratropical cyclones. Frontiers in Marine Science, 6, (2019): 446, doi:10.3389/fmars.2019.00446.Over the past decade, measurements from the climate-oriented ocean observing system have been key to advancing the understanding of extreme weather events that originate and intensify over the ocean, such as tropical cyclones (TCs) and extratropical bomb cyclones (ECs). In order to foster further advancements to predict and better understand these extreme weather events, a need for a dedicated observing system component specifically to support studies and forecasts of TCs and ECs has been identified, but such a system has not yet been implemented. New technologies, pilot networks, targeted deployments of instruments, and state-of-the art coupled numerical models have enabled advances in research and forecast capabilities and illustrate a potential framework for future development. Here, applications and key results made possible by the different ocean observing efforts in support of studies and forecasts of TCs and ECs, as well as recent advances in observing technologies and strategies are reviewed. Then a vision and specific recommendations for the next decade are discussed.This study was supported by the National Oceanic and Atmospheric Administration and JSPS KAKENHI (Grant Numbers: JP17K19093, JP16K12591, and JP16H01846)

Characterization of slow and fast phase nystagmus

A current literature review of the analog and digital process of vestibular and optical kinetic nystagmus reveals little agreement in the methods used by various labs. The strategies for detection of saccade (fast phase velocity component of nystagmus) vary between labs, and most of the process have not been evaluated and validated with a standard database. A survey was made of major vestibular labs in the U.S. that perform computer analyses of vestibular and optokinetic reflexes to stimuli, and a baseline was established from which to standardize data acquisition and analysis programs. The concept of an Error Index was employed as the criterium for evaluating the performance of the vestibular analysis software programs. The performance criterium is based on the detection of saccades and is the average of the percentages of missed detections and false detections. Evaluation of the programs produced results for lateral gaze with saccadic amplitude of one, two, three, five, and ten degrees with various signal-to-noise ratios. In addition, results were obtained for sinusoidal pursuit of 0.05, 0.10, and 0.50 Hz with saccades from one to ten degrees at various signal-to-noise ratios. Selection of the best program was made from the performance in the lateral gaze with three degrees of saccadic amplitude and in the 0.10 Hz sinusoid with three degrees of saccadic amplitude

Eye-tracking assistive technologies for individuals with amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis, also known as ALS, is a progressive nervous system disorder that affects nerve cells in the brain and spinal cord, resulting in the loss of muscle control. For individuals with ALS, where mobility is limited to the movement of the eyes, the use of eye-tracking-based applications can be applied to achieve some basic tasks with certain digital interfaces. This paper presents a review of existing eye-tracking software and hardware through which eye-tracking their application is sketched as an assistive technology to cope with ALS. Eye-tracking also provides a suitable alternative as control of game elements. Furthermore, artificial intelligence has been utilized to improve eye-tracking technology with significant improvement in calibration and accuracy. Gaps in literature are highlighted in the study to offer a direction for future research

Operational modal analysis and its application for SOFIA telescope assembly vibration measurements

The Stratospheric Observatory For Infrared Astronomy, SOFIA, is an airborne observatory that will serve the scientific community to study the universe in the infrared spectrum. SOFIA consists of a Boeing 747SP aircraft equipped with a 2.5 m telescope in the rear part of the fuselage. During operational flight, a door will be opened to allow a clear view into the sky. One particular challenge of such an observatory in an airborne environment is to provide a highly stable image in the focal plane, where the science instrument picks up the light from the telescope. Image jitter at the focal plane is caused by external disturbance loads, e.g. aircraft inertial loads and aerodynamic loads, which cause rigid as well as flexible body motion of the telescope. Flexible body motions play an important role in the pointing optimization effort. Therefore, a good understanding of the dynamic characteristics of the telescope structure needs to be generated. This study thesis discusses the methods of Operational Modal Analysis (OMA) in order to obtain such an understanding and shows how they can be applied to the SOFIA observatory development and improvement process with respect to pointing stabilization and image quality. Operational Modal Analysis acquires information about the dynamic characteristics of a structure in terms of eigenfrequencies, damping and mode shapes, without the need for explicit measurement of the vibration inducing loads. Since the exact influence of aerodynamic disturbance loads during operational flight conditions is not measurable, the OMA approach is a promising contribution the SOFIA optimization effort.SOFIA, das Stratosphären Observatorium für Infrarot Astronomie, ist ein fliegendes Observatorium, mit dem das Weltall astronomisch hautpsächlich im Bereich des Infrarotspektrums erforscht werden soll. Es handelt sich um ein umgebautes Flugzeug vom Typ Boeing 747SP, in dessen hintere Rumpfsektion ein Teleskop mit 2.5 m Spiegeldurchmesser eingebaut wurde. Eine sich im Fluge öffnende Schiebetür erlaubt dem Teleskop einen freien Blick in den Nachthimmel. Eine der Hauptschwierigkeiten eines Flugzeugobservatoriums wie SOFIA ist, dem wissenschaftlichen Instrument in der Fokalebene des Teleskopes ein ausreichend stabiles Bild zu überreichen. Nur ein unverwackeltes Bild ermöglicht hervorragende wissenschaftliche Ergebnisse. Störungen in der Bildbewegung werden durch externe Anregungen hervorgerufen, die sowohl aus der Flugzeugbewegung kommen als auch durch aerodynamische Lasten verursacht werden, welche auf das Teleskop einwirken. Diese Störungen bewirken zum einen, dass sich ungewollt das komplette Teleskop relativ zum Sternenhimmel bewegt (Starrkörperbewegung), als auch dass die Teleskopstruktur angeregt wird zu schwingen. Der Ausgleich dieser Schwingungen spielt eine wichtige Rolle im Bemühen die Ausrichtgenauigkeit des Teleskops zu verbessern. Um dies zu erreichen, ist ein gutes Verständnis der dynamischen Eigenschaften der Teleskopstruktur von Nöten. Die vorliegende Studienarbeit beschäftigt sich mit den Methoden der Operationellen Modalanalyse (OMA) als Möglichkeit dieses Verständnis zu erarbeiten. Die Arbeit zeigt, wie Operationelle Modalanalyse im SOFIA Projekt angewandt werden kann um die Optimierung von Ausrichtgenauigkeit und Bildqualität zu unterstützen. Mithilfe der Operationellen Modalanalyse können die Eigenfrequenzen, Dämpfungen und Schwingungsformen einer Struktur ermittelt werden, ohne dass dabei die anregenden Kräfte explizit gemessen werden müssen. Weil genau dieses Unterfangen während eines Fluges unter Beobachtungsbedingungen unmöglich ist -- besonders die Messung der auf der Struktur räumlich verteilten aerodynamischen Lasten -- erscheint der Ansatz der Operationellen Modalanalyse als vielversprechender Beitrag um die Leistungsfähigkeit des SOFIA Observatoriums zu optimieren

On Clustering and Evaluation of Narrow Domain Short-Test Corpora

En este trabajo de tesis doctoral se investiga el problema del agrupamiento de conjuntos especiales de documentos llamados textos cortos de dominios restringidos. Para llevar a cabo esta tarea, se han analizados diversos corpora y métodos de agrupamiento. Mas aún, se han introducido algunas medidas de evaluación de corpus, técnicas de selección de términos y medidas para la validez de agrupamiento con la finalidad de estudiar los siguientes problemas: -Determinar la relativa dificultad de un corpus para ser agrupado y estudiar algunas de sus características como longitud de los textos, amplitud del dominio, estilometría, desequilibrio de clases y estructura. -Contribuir en el estado del arte sobre el agrupamiento de corpora compuesto de textos cortos de dominios restringidos El trabajo de investigación que se ha llevado a cabo se encuentra parcialmente enfocado en el "agrupamiento de textos cortos". Este tema se considera relevante dado el modo actual y futuro en que las personas tienden a usar un "lenguaje reducido" constituidos por textos cortos (por ejemplo, blogs, snippets, noticias y generación de mensajes de textos como el correo electrónico y el chat). Adicionalmente, se estudia la amplitud del dominio de corpora. En este sentido, un corpus puede ser considerado como restringido o amplio si el grado de traslape de vocabulario es alto o bajo, respectivamente. En la tarea de categorización, es bastante complejo lidiar con corpora de dominio restringido tales como artículos científicos, reportes técnicos, patentes, etc. El objetivo principal de este trabajo consiste en estudiar las posibles estrategias para tratar con los siguientes dos problemas: a) las bajas frecuencias de los términos del vocabulario en textos cortos, y b) el alto traslape de vocabulario asociado a dominios restringidos. Si bien, cada uno de los problemas anteriores es un reto suficientemente alto, cuando se trata con textos cortos de dominios restringidos, la complejidad del problema se incrPinto Avendaño, DE. (2008). On Clustering and Evaluation of Narrow Domain Short-Test Corpora [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/2641Palanci

Coastal high-frequency radars in the Mediterranean - Part 2: Applications in support of science priorities and societal needs

The Mediterranean Sea is a prominent climate-change hot spot, with many socioeconomically vital coastal areas being the most vulnerable targets for maritime safety, diverse met-ocean hazards and marine pollution. Providing an unprecedented spatial and temporal resolution at wide coastal areas, high-frequency radars (HFRs) have been steadily gaining recognition as an effective land-based remote sensing technology for continuous monitoring of the surface circulation, increasingly waves and occasionally winds. HFR measurements have boosted the thorough scientific knowledge of coastal processes, also fostering a broad range of applications, which has promoted their integration in coastal ocean observing systems worldwide, with more than half of the European sites located in the Mediterranean coastal areas. In this work, we present a review of existing HFR data multidisciplinary science-based applications in the Mediterranean Sea, primarily focused on meeting end-user and science-driven requirements, addressing regional challenges in three main topics: (i) maritime safety, (ii) extreme hazards and (iii) environmental transport process. Additionally, the HFR observing and monitoring regional capabilities in the Mediterranean coastal areas required to underpin the underlying science and the further development of applications are also analyzed. The outcome of this assessment has allowed us to provide a set of recommendations for future improvement prospects to maximize the contribution to extending science-based HFR products into societally relevant downstream services to support blue growth in the Mediterranean coastal areas, helping to meet the UN's Decade of Ocean Science for Sustainable Development and the EU's Green Deal goals

Coastal high-frequency radars in the Mediterranean ??? Part 2: Applications in support of science priorities and societal needs

International audienceThe Mediterranean Sea is a prominent climate-change hot spot, with many socioeconomically vital coastal areas being the most vulnerable targets for maritime safety, diverse met-ocean hazards and marine pollution. Providing an unprecedented spatial and temporal resolution at wide coastal areas, high-frequency radars (HFRs) have been steadily gaining recognition as an effective land-based remote sensing technology for continuous monitoring of the surface circulation, increasingly waves and occasionally winds. HFR measurements have boosted the thorough scientific knowledge of coastal processes, also fostering a broad range of applications, which has promoted their integration in coastal ocean observing systems worldwide, with more than half of the European sites located in the Mediterranean coastal areas. In this work, we present a review of existing HFR data multidisciplinary science-based applications in the Mediterranean Sea, primarily focused on meeting end-user and science-driven requirements, addressing regional challenges in three main topics: (i) maritime safety, (ii) extreme hazards and (iii) environmental transport process. Additionally, the HFR observing and monitoring regional capabilities in the Mediterranean coastal areas required to underpin the underlying science and the further development of applications are also analyzed. The outcome of this assessment has allowed us to provide a set of recommendations for future improvement prospects to maximize the contribution to extending science-based HFR products into societally relevant downstream services to support blue growth in the Mediterranean coastal areas, helping to meet the UN's Decade of Ocean Science for Sustainable Development and the EU's Green Deal goals