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Energy Harvesting for Structural Health Monitoring Sensor Networks
This report has been developed based on information exchanges at a 2.5-day workshop on energy harvesting for embedded structural health monitoring (SHM) sensing systems that was held June 28-30, 2005, at Los Alamos National Laboratory. The workshop was hosted by the LANL/UCSD Engineering Institute (EI). This Institute is an education- and research-focused collaboration between Los Alamos National Laboratory (LANL) and the University of California, San Diego (UCSD), Jacobs School of Engineering. A Statistical Pattern Recognition paradigm for SHM is first presented and the concept of energy harvesting for embedded sensing systems is addressed with respect to the data acquisition portion of this paradigm. Next, various existing and emerging sensing modalities used for SHM and their respective power requirements are summarized, followed by a discussion of SHM sensor network paradigms, power requirements for these networks and power optimization strategies. Various approaches to energy harvesting and energy storage are discussed and limitations associated with the current technology are addressed. This discussion also addresses current energy harvesting applications and system integration issues. The report concludes by defining some future research directions and possible technology demonstrations that are aimed at transitioning the concept of energy harvesting for embedded SHM sensing systems from laboratory research to field-deployed engineering prototypes
The Palomar Transient Factory: System Overview, Performance and First Results
The Palomar Transient Factory (PTF) is a fully-automated, wide-field survey
aimed at a systematic exploration of the optical transient sky. The transient
survey is performed using a new 8.1 square degree camera installed on the
48-inch Samuel Oschin telescope at Palomar Observatory; colors and light curves
for detected transients are obtained with the automated Palomar 60-inch
telescope. PTF uses eighty percent of the 1.2-m and fifty percent of the 1.5-m
telescope time. With an exposure of 60-s the survey reaches a depth of
approximately 21.3 in g' and 20.6 in R (5 sigma, median seeing). Four major
experiments are planned for the five-year project: 1) a 5-day cadence supernova
search; 2) a rapid transient search with cadences between 90 seconds and 1 day;
3) a search for eclipsing binaries and transiting planets in Orion; and 4) a
3-pi sr deep H-alpha survey. PTF provides automatic, realtime transient
classification and follow up, as well as a database including every source
detected in each frame. This paper summarizes the PTF project, including
several months of on-sky performance tests of the new survey camera, the
observing plans and the data reduction strategy. We conclude by detailing the
first 51 PTF optical transient detections, found in commissioning data.Comment: 12 pages, 11 figures, 3 tables, submitted to PAS
Modeling the Young Sun's Solar Wind and its Interaction with Earth's Paleomagnetosphere
We present a focused parameter study of solar wind - magnetosphere
interaction for the young Sun and Earth, Ga ago, that relies on
magnetohydrodynamic (MHD) simulations for both the solar wind and the
magnetosphere. By simulating the quiescent young Sun and its wind we are able
to propagate the MHD simulations up to Earth's magnetosphere and obtain a
physically realistic solar forcing of it. We assess how sensitive the young
solar wind is to changes in the coronal base density, sunspot placement and
magnetic field strength, dipole magnetic field strength and the Sun's rotation
period. From this analysis we obtain a range of plausible solar wind conditions
the paleomagnetosphere may have been subject to. Scaling relationships from the
literature suggest that a young Sun would have had a mass flux different from
the present Sun. We evaluate how the mass flux changes with the aforementioned
factors and determine the importance of this and several other key solar and
magnetospheric variables with respect to their impact on the
paleomagnetosphere. We vary the solar wind speed, density, interplanetary
magnetic field strength and orientation as well as Earth's dipole magnetic
field strength and tilt in a number of steady-state scenarios that are
representative of young Sun-Earth interaction. This study is done as a first
step of a more comprehensive effort towards understanding the implications of
Sun-Earth interaction for planetary atmospheric evolution.Comment: 16 pages, 7 figure
Protein versus DNA as a marker for peripheral blood mononuclear cell counting
Quantitative analysis of intracellular analytes requires an accurate and precise assay not only for the quantitation of the analytes, but also for the quantitation of the number of cells in which they were determined. In this technical note we compare protein and DNA as markers for the number of peripheral blood mononuclear cells (PBMCs) isolated from whole blood. The protein content of samples was highly influenced by red blood cell contamination and was, therefore, a less suitable marker. The DNA-based method was unaffected by red blood cell contamination and was finally validated over a range from 10 × 106 to 300 × 106 PBMCs/mL
Нейроендокринний супровід поліваріантних ефектів біоактивної води Нафтуся на рівень хронічного стресу у жінок з різним оваріальним статусом
Проанализированы изменения нейроэндокринных показателен, сопутствующие поливариантным эффектам биоактивной воды Нафтуся курорта Трускавец на уровень хронического стресса у женщин детородного возраста с различным овариальным статусом. Обнаружена значительная (R=0,59) каноническая корреляционная связь между динамикой нейро-гормонального индекса стресса, с одной стороны, и вегетативной реактивности, лютеинизирующего гормона, тиреотропного гормона, тироксина и прогестерона - с другой стороны.The changes in neuroendocrine parameters, concomitant multivariate effects of bioactive water Naftussya spa Truskavets to the level of chronic stress in women of childbearing age with different ovarian status. A significant (R=0,59) canonical correlation between the dynamics of the neuro-hormonal index of stress, on the one hand, and autonomic reactivity, luteinizing hormone, thyroid-stimulating hormone, thyroxine and progesterone - the other side
The Effects of Climate Change on Harp Seals (Pagophilus groenlandicus)
Harp seals (Pagophilus groenlandicus) have evolved life history strategies to exploit seasonal sea ice as a breeding platform. As such, individuals are prepared to deal with fluctuations in the quantity and quality of ice in their breeding areas. It remains unclear, however, how shifts in climate may affect seal populations. The present study assesses the effects of climate change on harp seals through three linked analyses. First, we tested the effects of short-term climate variability on young-of-the year harp seal mortality using a linear regression of sea ice cover in the Gulf of St. Lawrence against stranding rates of dead harp seals in the region during 1992 to 2010. A similar regression of stranding rates and North Atlantic Oscillation (NAO) index values was also conducted. These analyses revealed negative correlations between both ice cover and NAO conditions and seal mortality, indicating that lighter ice cover and lower NAO values result in higher mortality. A retrospective cross-correlation analysis of NAO conditions and sea ice cover from 1978 to 2011 revealed that NAO-related changes in sea ice may have contributed to the depletion of seals on the east coast of Canada during 1950 to 1972, and to their recovery during 1973 to 2000. This historical retrospective also reveals opposite links between neonatal mortality in harp seals in the Northeast Atlantic and NAO phase. Finally, an assessment of the long-term trends in sea ice cover in the breeding regions of harp seals across the entire North Atlantic during 1979 through 2011 using multiple linear regression models and mixed effects linear regression models revealed that sea ice cover in all harp seal breeding regions has been declining by as much as 6 percent per decade over the time series of available satellite data
Small firms and patenting revisited
In order to observe a patent application at the firm level two conditions need to be met: new products need to be of patentable quality, which depends both on the degree of novelty of innovations and on the total number (portfolio) of innovations; and the benefits of patents
need to be higher than the costs of owning them. Analyzing the patent propensity of small and large UK firms using a novel innovation-level survey (the SIPU survey) linked to Community Innovation Survey data we find that when we consider the whole innovation portfolio smaller firms do patent less than larger firms. However, using data on individual
innovations, we find that smaller firms are no less likely to patent any specific innovation than larger firms. We argue that size differences in the probability to patent relate primarily to the ‘portfolio effect’, i.e. larger firms generate more innovations than smaller firms and therefore are more likely to create one or more which are patentable. As for the decision to patent a patentable innovation, we find that cost barriers, more than issues of innovation quality or enforceability, deter small firms from patenting specific innovations. Measures to address the costs of patenting for smaller firms – perhaps by considering patents as eligible
costs for R&D tax credits – and/or subsidizing SMEs’ participation in IP litigation schemes may both encourage patent use by smaller firms
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