SPECTRASAT: A concept for the collection of global directional wave spectra

The synthetic aperture radar (SAR) imagery from SEASAT revealed a rich tapestry of backscatter patterns from the surface of the ocean. Although still far from being fully understood, these patterns occurred on nearly all spatial scales accessible to the SAR, that is from its spatial resolution of 25 m to its full swath width of 100 km. Futhermore, the backscatter signature appear to reveal a large variety of atmospheric and oceanic processes that occur above, at, and below the ocean surface. Proper interpretation of these signatures of varying scales with respect to their underlying geophysical causes is a major objective of SAR ocean research. Even now, however, it is clear that SAR offers a unique means to monitor wind and waves over global scales. A properly designed, configured, and complimented orbiting SAR system should yield substantial improvements in operational forecasts vital to marine activities. Since wind and wave information is optimally extracted in the spectral domain, the name SPECTRASAT is proposed for this global collection scheme

Operational wave forecasting with spaceborne SAR: Prospects and pitfalls

Measurements collected in the Shuttle Imaging Radar (SIR-B) Extreme Waves Experiment confirm the ability of Synthetic Aperture Radar (SAR) to yield useful estimates of wave directional energy spectra over global scales, at least for shuttle altitudes. However, azimuth fall-off effects tend to become severe for wavelengths shorter than about 100 m in most sea states. Moreover, the azimuth fall-off problem becomes increasingly severe as the platform altitude increases beyond 300 km. The most viable solution to the global wave measurements problem may be a low altitude spacecraft containing a combination of both the SAR and the Radar Ocean Wave Spectrometry (ROWS). Such a combination could have a synergy which yield global spectral estimates superior to those of either instrument singly employed

A significant post-launch calibration experiment for the SEASAT-A SAR

A technique for periodically monitoring the impulse response function of the SEASAT-A synthetic aperture radar is outlined that yields most of the significant contributors to the overall instrument transfer function. The essential measurement involves exciting the total SAR system at L-band with a strong point source scatterer, receiving via the normal S-band analog data link, and finally sampling and processing only a small subset of data in the immediate vicinity of the strong point source

The Seasat SAR Wind and Ocean Wave Monitoring Capabilities: A case study for pass 1339m

A well organized low energy 11 sec. swell system off the East Coast of the U.S. was detected with the Seasat Synthetic Aperture Radar and successfully tracked from deep water, across the continental shelf, and into shallow water. In addition, a less organized 7 sec. system was tentatively identified in the imagery. Both systems were independently confirmed with simultaneous wave spectral measurements from a research pier, aircraft laser profilometer data, and Fleet Numerical Spectral Ocean Wave Models

Tracking ocean wave spectrum from SAR images

An end to end algorithm for recovery of ocean wave spectral peaks from Synthetic Aperture Radar (SAR) images is described. Current approaches allow precisions of 1 percent in wave number, and 0.6 deg in direction

Data Mining to Uncover Heterogeneous Water Use Behaviors From Smart Meter Data

Knowledge on the determinants and patterns of water demand for different consumers supports the design of customized demand management strategies. Smart meters coupled with big data analytics tools create a unique opportunity to support such strategies. Yet, at present, the information content of smart meter data is not fully mined and usually needs to be complemented with water fixture inventory and survey data to achieve detailed customer segmentation based on end use water usage. In this paper, we developed a data‐driven approach that extracts information on heterogeneous water end use routines, main end use components, and temporal characteristics, only via data mining existing smart meter readings at the scale of individual households. We tested our approach on data from 327 households in Australia, each monitored with smart meters logging water use readings every 5 s. As part of the approach, we first disaggregated the household‐level water use time series into different end uses via Autoflow. We then adapted a customer segmentation based on eigenbehavior analysis to discriminate among heterogeneous water end use routines and identify clusters of consumers presenting similar routines. Results revealed three main water end use profile clusters, each characterized by a primary end use: shower, clothes washing, and irrigation. Time‐of‐use and intensity‐of‐use differences exist within each class, as well as different characteristics of regularity and periodicity over time. Our customer segmentation analysis approach provides utilities with a concise snapshot of recurrent water use routines from smart meter data and can be used to support customized demand management strategies.TU Berlin, Open-Access-Mittel - 201

Special issue on studies in Late Modern English historical phonology using the Eighteenth-Century English Phonology Database (ECEP): introduction

Since Charles Jones referred to the eighteenth and nineteenth centuries as the ‘Cinderellas of English historical linguistic study’ (1989: 279), there has been a great deal of progress in research on this period, but, as Beal (2012: 22) points out, much of this has been in the fields of syntax, morphology, lexis, pragmatics, sociolinguistics and the normative tradition. Beal argues that the availability of corpora of Late Modern English texts has greatly facilitated research in these areas, but, since creating phonological corpora for periods antedating the invention of sound recording is a challenging proposition, the historical phonology of Late Modern English has benefited much less from the corpus revolution. To redress this imbalance, the editors of this issue, with technical support from the Humanities Research Institute, University of Sheffield, created the Eighteenth-Century English Phonology Database (ECEP), which is freely available at www.dhi.ac.uk/projects/ecep

ARHGEF18/p114RhoGEF Coordinates PKA/CREB Signaling and Actomyosin Remodeling to Promote Trophoblast Cell-Cell Fusion During Placenta Morphogenesis

Coordination of cell-cell adhesion, actomyosin dynamics and gene expression is crucial for morphogenetic processes underlying tissue and organ development. Rho GTPases are main regulators of the cytoskeleton and adhesion. They are activated by guanine nucleotide exchange factors in a spatially and temporally controlled manner. However, the roles of these Rho GTPase activators during complex developmental processes are still poorly understood. ARHGEF18/p114RhoGEF is a tight junction-associated RhoA activator that forms complexes with myosin II, and regulates actomyosin contractility. Here we show that p114RhoGEF/ARHGEF18 is required for mouse syncytiotrophoblast differentiation and placenta development. In vitro and in vivo experiments identify that p114RhoGEF controls expression of AKAP12, a protein regulating protein kinase A (PKA) signaling, and is required for PKA-induced actomyosin remodeling, cAMP-responsive element binding protein (CREB)-driven gene expression of proteins required for trophoblast differentiation, and, hence, trophoblast cell-cell fusion. Our data thus indicate that p114RhoGEF links actomyosin dynamics and cell-cell junctions to PKA/CREB signaling, gene expression and cell-cell fusion

Human larynx motor cortices coordinate respiration for vocal-motor control.

Vocal flexibility is a hallmark of the human species, most particularly the capacity to speak and sing. This ability is supported in part by the evolution of a direct neural pathway linking the motor cortex to the brainstem nucleus that controls the larynx the primary sound source for communication. Early brain imaging studies demonstrated that larynx motor cortex at the dorsal end of the orofacial division of motor cortex (dLMC) integrated laryngeal and respiratory control, thereby coordinating two major muscular systems that are necessary for vocalization. Neurosurgical studies have since demonstrated the existence of a second larynx motor area at the ventral extent of the orofacial motor division (vLMC) of motor cortex. The vLMC has been presumed to be less relevant to speech motor control, but its functional role remains unknown. We employed a novel ultra-high field (7T) magnetic resonance imaging paradigm that combined singing and whistling simple melodies to localise the larynx motor cortices and test their involvement in respiratory motor control. Surprisingly, whistling activated both 'larynx areas' more strongly than singing despite the reduced involvement of the larynx during whistling. We provide further evidence for the existence of two larynx motor areas in the human brain, and the first evidence that laryngeal-respiratory integration is a shared property of both larynx motor areas. We outline explicit predictions about the descending motor pathways that give these cortical areas access to both the laryngeal and respiratory systems and discuss the implications for the evolution of speech