Shop Notes

Contains reports on two research projects

Preliminary assessment of industrial needs for an advanced ocean technology

A quick-look review of selected ocean industries is presented for the purpose of providing NASA OSTA with an assessment of technology needs and market potential. The size and growth potential, needs and problem areas, technology presently used and its suppliers, are given for industries involved in deep ocean mining, petrochemicals ocean energy conversion. Supporting services such as ocean bottom surveying; underwater transportation, data collection, and work systems; and inspection and diving services are included. Examples of key problem areas that are amenable to advanced technology solutions are included. Major companies are listed

Analysis and Implementation of Median Type Filters

Median filters are a special class of ranked order filters used for smoothing signals. These filters have achieved- success in speech processing, image processing, and other impulsive noise environments where linear filters have proven inadequate. Although the implementation of a median filter requires only a simple digital operation, its properties are not easily analyzed. Even so, a number of properties have been exhibited in the literature. In this thesis, a new tool, known as threshold decomposition is introduced for the analysis and implementation of median type filters. This decomposition of multi-level signals into sets of binary signals has led to significant theoretical and practical breakthroughs in the area of median filters. A preliminary discussion on using the threshold decomposition as an algorithm for a fast and parallel VLSI Circuit implementation of ranked filters is also presented* In addition, the theory is developed both for determining the number of signals which are invariant to arbitrary window width median filters when any number of quantization levels are allowed and for counting or estimating the number of passes required to produce a root- i.e. invariant signal, for binary signals. Finally, the analog median filter is defined and proposed for analysis of the standard discrete median filter in cases with a large sample size or when the associated statistics would be simpler in the continuu

Cross-Modal Health State Estimation

Individuals create and consume more diverse data about themselves today than any time in history. Sources of this data include wearable devices, images, social media, geospatial information and more. A tremendous opportunity rests within cross-modal data analysis that leverages existing domain knowledge methods to understand and guide human health. Especially in chronic diseases, current medical practice uses a combination of sparse hospital based biological metrics (blood tests, expensive imaging, etc.) to understand the evolving health status of an individual. Future health systems must integrate data created at the individual level to better understand health status perpetually, especially in a cybernetic framework. In this work we fuse multiple user created and open source data streams along with established biomedical domain knowledge to give two types of quantitative state estimates of cardiovascular health. First, we use wearable devices to calculate cardiorespiratory fitness (CRF), a known quantitative leading predictor of heart disease which is not routinely collected in clinical settings. Second, we estimate inherent genetic traits, living environmental risks, circadian rhythm, and biological metrics from a diverse dataset. Our experimental results on 24 subjects demonstrate how multi-modal data can provide personalized health insight. Understanding the dynamic nature of health status will pave the way for better health based recommendation engines, better clinical decision making and positive lifestyle changes.Comment: Accepted to ACM Multimedia 2018 Conference - Brave New Ideas, Seoul, Korea, ACM ISBN 978-1-4503-5665-7/18/1

Three dimensional rotational angiography imaging of double aortic arch vascular ring

Three dimensional (3D) rotational angiography is a technique used increasingly for imaging in congenital heart disease. Here the use of this technique for imaging of double aortic arch vascular ring is described and the advantages of this modality. are discussed. 3D rotational angiography is an excellent tool for imaging of various vascular anomalies. It provides high quality accurate images through a quick and safe procedure.peer-reviewe

Shop Notes

Contains reports on four research projects

Operation of EMEP ‘supersites’ in the United Kingdom. Annual report for 2008.

As part of its commitment to the UN-ECE Convention on Long-range Transboundary Air Pollution the United Kingdom operates two ‘supersites’ reporting data to the Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP). This report provides the annual summary for 2008, the second full calendar year of operation of the first EMEP ‘supersite’ to be established in the United Kingdom. Detailed operational reports have been submitted to Defra every 3 months, with unratified data. This annual report contains a summary of the ratified data for 2008. The EMEP ‘supersite’ is located in central southern Scotland at Auchencorth (3.2oW, 55.8oN), a remote rural moorland site ~20 km south-west of Edinburgh. Monitoring operations started formally on 1 June 2006. In addition to measurements made specifically under this contract, the Centre for Ecology & Hydrology also acts as local site operator for measurements made under other UK monitoring networks: the Automated Urban and Rural Network (AURN), the UK Eutrophication and Acidification Network (UKEAP), the UK Hydrocarbons Network, and the UK Heavy Metals Rural Network. Some measurements were also made under the auspices of the ‘Air Pollution Deposition Processes’ contract. All these associated networks are funded by Defra. This report summarises the measurements made between January and December 2008, and presents summary statistics on average concentrations. The site is dominated by winds from the south-west, but wind direction data highlight potential sources of airborne pollutants (power stations, conurbations). The average diurnal patterns of gases and particles are consistent with those expected for a remote rural site. The frequency distributions are presented for data where there was good data capture throughout the whole period. Some components (e.g. black carbon) show log-normal frequency distributions, while other components (e.g. ozone) have more nearly normal frequency distributions. A case study is presented for a period in June 2008, showing the influence of regional air pollutants at this remote rural site. All the data reported under the contract are shown graphically in the Appendix

Bowhead Whales Along the Chukotka Coast in Autumn

Bowhead whales (Balaena mysticetus) were seen in autumn 1992 and 1993 only along the northern coast of Chukotka, Russia, although an extensive area of the Chukchi Sea was searched during ship cruises. Single-day counts for 76 and 50 bowheads were made on 1 October 1992 and 3 October 1993, respectively, with only a few whales seen on other days. Whales seen between Cape Schmidt and Cape Vankarem on 1 October 1992 appeared to be feeding, but there was no means to detect or sample subsurface forage that year. On 3 October 1993, bowheads appeared to be feeding in an area where a 5 m x 8 km patch of zooplankton was identified, via acoustics, at 25-30 m in water 35 m deep. A vertical-tow sample near the patch indicated the euphausiid Thysanoessa rachii, a common bowhead prey species, was abundant in the water column. The location of the zooplankton patch corresponded with a sharp salinity (proxy density) gradient. In addition, whale distribution coincided with a surface thermal boundary, identified by satellite-borne Advanced Very High Resolution Radiometer (AVHRR) imagery. The confinement of bowhead sightings to the northern coast of Chukotka in 1992-93 corresponds to reports from autumn surveys in 1979, 1980 and 1990, while the association of whales with physical oceanographic fronts is similar to findings from a study of bowhead feeding areas in the southern Beaufort Sea. These observations suggest that the Chukotka coast may be an important feeding or staging area for the Bering Sea stock and that oceanographic patterns influencing whale occurrence may be identifiable from standard oceanographic measurements.Key words: bowhead whale, Balaena mysticetus, migration, Chukchi Sea, Bering Sea, Chukotka, Thysanoessa rachii, satellite imagery, AVHRRDurant l'automne de 1992 et celui de 1993, on n'a pu observer de baleines boréales (Balaena mysticetus) que le long de la côte nord de Chukotka (Russie), bien que des recherches aient eu lieu dans une zone étendue de la mer des Tchouktches lors de croisières en bateau. Des comptages de 76 et 50 baleines boréales ont été obtenus respectivement le 1er octobre 1992 et le 3 octobre 1993, alors qu'on n'en a observé que quelques-unes les autres jours. Les baleines observées entre Cape Schmidt et Cape Vankarem le 1er octobre 1992 semblaient être en train de s'alimenter, mais on ne disposait pas de moyens pour détecter le genre de nourriture sous la surface, ni pour en prélever un échantillon cette année-là. Le 3 octobre 1993, les baleines semblaient s'alimenter là où une plaque de zooplancton de 5 m x 8 km avait été identifiée par méthode acoustique entre 25 et 30 m de profondeur, dans une zone de 35 m de fond. Un échantillon prélevé par hâlage vertical près de la plaque a indiqué que l'euphausiacé Thysanoessa rachii, une proie courante de la baleine boréale, était abondant dans la colonne d'eau. L'emplacement de la plaque de zooplancton correspondait à un fort gradient de salinité (approximation par la densité). De plus, la distribution des baleines coïncidait avec une limite thermique de surface identifiée au moyen de l'imagerie par radiomètre perfectionné à très haute résolution, transporté par satellite. Le confinement des observations de baleines à la côte nord de Chukotka en 1992-93 correspond aux rapports des relevés d'automne de 1979, 1980 et 1990, tandis que l'association des baleines à des fronts physiques océanographiques cadre avec les résultats d'une étude des zones d'alimentation de la baleine boréale dans le sud de la mer de Beaufort. Ces observations suggèrent que la côte de Chukotka pourrait être une importante zone d'alimentation ou de rassemblement pour la population de la mer de Béring, et que les caractéristiques océanographiques qui influencent la présence des baleines pourraient être identifiables à partir des mesures océanographiques courantes.Mots clés: baleine boréale, Balaena mysticetus, migration, mer des Tchouktches, mer de Béring, Chukotka, Thysanoessa rachii, imagerie par satellite, radiomètre perfectionné à très haute résolutio

Ultrafast diode-pumped Ti:sapphire laser with broad tunability

We report a broadly wavelength-tunable femtosecond diode-pumped Ti:sapphire laser, passively mode-locked using both semiconductor saturable absorber mirror (SESAM) and Kerr-lens mode-locking (KLM) techniques. Using two pump laser diodes (operating at 450 nm), an average output power as high as 433 mW is generated during mode-locking with the SESAM. A tunability range of 37 nm (788-825 nm) was achieved with the shortest pulse duration of 62 fs at 812 nm. In the KLM regime, an average output power as high as 382 mW, pulses as short as 54 fs, and a tunability of 120 nm (755-875 nm) are demonstrated