Miracle-dz/UniFAR-FTUs huggingface dataset:
Polynomial background estimation using visible light video streams for robust automatic detection in a maritime environment

For naval surveillance, automatic detection of surface objects, like vessels, in a maritime environment is an important contribution of the Electro-Optical (EO) sensor systems on board. Based on previous research using single images, a background estimation approach using low-order polynomials is proposed for the automatic detection of objects in a maritime environment. The polynomials are fitted to the intensity values in the image after which the deviation between the fitted intensity values and the measured intensity values are used for detection. The research presented in this paper, includes the time information by using video streams instead of single images. Hereby, the level of fusing time information and the number of frames necessary for stable detection and tracking behaviour are analysed and discussed. The performance of the detection approach is tested on a, during the fall of 2007, collected extensive dataset of maritime pictures in the Mediterranean Sea and in the North Sea on board of an Air Defence Command frigate, HNLMS Tromp.
Rock formation characterization for CO2-EOR and carbon geosequestration; 3D seismic amplitude and coherency anomalies, Wellington Field, Kansas, USA

In this paper, we present a workflow for a Mississipian carbonates characterization case-study integrating poststack seismic attributes, well-logs porosities, and seismic modeling to explore relating changes in small-scale “lithofacies” properties and/or sub-seismic resolution faulting to key amplitude and coherency 3D seismic attributes. The main objective of this study is to put emphasis on reservoir characterization that is both optimized for and subsequently benefiting from pilot tertiary CO2-EOR in preparation for future carbon geosequestration in a depleting reservoir and a deep saline aquifer. The extracted 3D seismic coherency attribute indicated anomalous features that can be interpreted as a lithofacies change or a sub-seismic resolution faulting. A 2D finite difference modeling has been undertaken to understand and potentially build discriminant attributes to map structural and/or lithofacies anomalies of interest especially when embarking upon CO2-EOR and/or carbon sequestration monitoring and management projects.
RNA structures and dynamics with Å resolution revealed by x-ray free-electron lasers

RNA macromolecules, like proteins, fold to assume shapes that are intimately connected to their broadly recognized biological functions; however, because of their high charge and dynamic nature, RNA structures are far more challenging to determine. We introduce an approach that exploits the high brilliance of x-ray free-electron laser sources to reveal the formation and ready identification of angstrom-scale features in structured and unstructured RNAs. Previously unrecognized structural signatures of RNA secondary and tertiary structures are identified through wide-angle solution scattering experiments. With millisecond time resolution, we observe an RNA fold from a dynamically varying single strand through a base-paired intermediate to assume a triple-helix conformation. While the backbone orchestrates the folding, the final structure is locked in by base stacking. This method may help to rapidly characterize and identify structural elements in nucleic acids in both equilibrium and time-resolved experiments.
The Predictive Uncertainty of Land Surface Fluxes in Response to Increasing Ambient Carbon Dioxide

Abstract The exchange of water vapor and carbon dioxide (CO2) between the land surface and the atmosphere plays an important role in numerical weather forecasting and climate change prediction using general circulation models. In this study, a typical representation of photosynthesis as used in recent soil–vegetation–atmosphere transfer schemes has been analyzed within a Monte Carlo–based uncertainty estimation framework to estimate the predictive uncertainty of land surface fluxes in response to increasing levels of ambient CO2. The comparison of predicted latent heat and carbon fluxes with measurements from a two-week concentrated field campaign within the Northern Hemisphere Climate Processes Land Surface Experiment (NOPEX) project identified the problem of model equifinality in that many different model parameterizations are shown to be able to reproduce the observed data acceptably well. The same parameter sets, however, lead to the prediction of a wide range of possible responses of latent heat and .
Metamorphism in the Martian crust

Compositions of basaltic and ultramafic rocks analyzed by Mars rovers and occurring as Martian meteorites allow predictions of metamorphic mineral assemblages that would form under various thermophysical conditions. Key minerals identified by remote sensing roughly constrain temperatures and pressures in the Martian crust. We use a traditional metamorphic approach (phase diagrams) to assess low‐grade/hydrothermal equilibrium assemblages. Basaltic rocks should produce chlorite + actinolite + albite + silica, accompanied by laumontite, pumpellyite, prehnite, or serpentine/talc. Only prehnite‐bearing assemblages have been spectrally identified on Mars, although laumontite and pumpellyite have spectra similar to other uncharacterized zeolites and phyllosilicates. Ultramafic rocks are predicted to produce serpentine, talc, and magnesite, all of which have been detected spectrally on Mars. Mineral assemblages in both basaltic and ultramafic rocks constrain fluid compositions to be H2O‐rich and CO2‐poor. We confirm the hypothesis that low‐grade/hydrothermal metamorphism affected the Noachian crust on Mars, which has been excavated in large craters. We estimate the geothermal gradient (>20 °C km−1) required to produce the observed assemblages. This gradient is higher than that estimated from radiogenic heat‐producing elements in the crust, suggesting extra heating by regional hydrothermal activity.
Geology and petroleum potential of the Fairway Basin in the Tasman Sea

The Fairway Basin is a large, generally north – south-trending, sediment-filled structure in water 1500 – 3000 m deep, on the eastern slope of the Lord Howe Rise in the Tasman Sea, and is partly within Australian jurisdiction. It was poorly known until a few years ago, when seismic profiling and piston coring cruises were carried out. The basin, about 1100 km long and 120 – 200 km wide, can be divided into three segments—north, central and south—that trend northwest, north and north-northwest, respectively. All three segments probably formed by thinning of continental crust during breakup of Lord Howe Rise and surrounding aseismic continental ridges in the Late Cretaceous and Paleocene. Normal faulting, large inputs of terrigenous sediment and subsidence to bathyal marine depths occurred during that time. A period of compression, perhaps related to overthrusting on New Caledonia, occurred in the Eocene, leading to uplift (and in parts, erosion) of northern Lord Howe Rise, and reversal of faulting in the basin. By the Oligocene, the area was again in bathyal depths, and pelagic ooze and some turbidites accumulated. The basinal sequence is generally 2000 – 4000 m thick, with 1200 – 3200 m of Cretaceous to Eocene sediment concentrated in depocentres, capped by 500 – 800 m of Oligocene and younger sediment. In the depocentres, numerous sedimentary diapirs pierce sedimentary sequences. The sedimentary diapirs appear to be fed by Cretaceous muds deposited during rifting. Often, these diapirs are overlain by faults extending to the seafloor, and hummocky bathymetry is possibly caused by fluid escape. The overall geology suggests that the Fairway Basin may be a large frontier hydrocarbon province. Seismic profiles display a bottom-simulating reflector above many depocentres, 500 – 700 m below the seafloor. The bottom-simulating reflector has positive polarity, which could result from a diagenetic phase transformation, a thin gas hydrate layer with a sharp top, or from the sharp base of a gas layer (probably beneath gas hydrates). Standard piston cores taken above diapirs and apparent fluid-escape features have recovered little gas. Other than drilling, the next steps in assessing petroleum potential are to clearly document fluid-escape structures, and to sample any fluids emitted for hydrocarbons.
Plate boundary readjustment in oblique convergence: Example of the Neogene of Hispaniola, Greater Antilles

The Haitian fold‐and‐thrust belt is the major mountain belt of Haiti (western part of Hispaniola, Greater Antilles) and resembles a compressive restraining bend between the two major faults which have driven the opening of the Cayman Basin since the Eocene. During the rifting stage, from the middle to the late Eocene, this area underwent an extensional evolution with fissural volcanic activity along NE‐SW tilted blocks. The Haitian fold‐and‐thrust belt was constructed from the Early Miocene until the Present by stacking sedimentary units into a collisional wedge perpendicular to the tilted blocks, which was propagating to the southwest. During the construction of the wedge, piggyback basins were formed and progressively uplifted. During the late Neogene, convergence is localized in the Cul‐de‐Sac‐Enriquillo trough where the active front proceeds southward onto the Beata ridge. In this area, Miocene to Quaternary wrench structures of the lower plate, like the Southern Peninsula and the Enriquillo‐Plantain Garden faults, are reactivated as normal faults, owing to the loading of the fold‐and‐thrust belt.
Fire impacts on surface heat, moisture and carbon fluxes from a tropical savanna in northern Australia

Savannas form a large fraction of the total tropical vegetation and are extremely fire prone. We measured radiative, energy and carbon exchanges over unburned and burned (both before and after low and moderate intensity fires) open forest savanna at Howard Springs, Darwin, Australia. Fire affected the radiative balance immediately following fire through the consumption of the grass-dominated understorey and blackening of the surface. Albedo was halved following fire of both intensities (from 0.12 to 0.07 and from 0.11 to 0.06 for the moderate and low intensity sites, respectively), but the recovery of albedo was dependent on the initial fire intensity. The low intensity fire caused little canopy damage with little impact on the surface energy balance and only a slight increase in Bowen ratio. However the moderate fire resulted in a comprehensive canopy scorch and almost complete leaf drop in the weeks following fire. The shutdown of most leaves within the canopy reduced transpiration and altered energy partitioning. Leaf death and shedding also resulted in a cessation of ecosystem carbon uptake and the savanna turned from a sink to a source of carbon to the atmosphere because of the continued ecosystem respiration. Post-fire, the Bowen ratio increased greatly due to large increases in sensible heat fluxes. These changes in surface energy exchange following fire, when applied at the landscape scale, may have impacts on climate through local changes in circulation patterns and changes in regional heating, precipitation and monsoon circulation.
Review on light management by nanostructures in chalcopyrite solar cells

Light management has gained wide interest for various types of solar cells. This paper reviews the application of nanostructures for light management to chalcopyrite (CIGSe) type solar cells. Firstly, the relevance of light management for CIGSe solar cells will be introduced and concepts of nanostructures for absorption enhancement discussed. The development of ultra-thin CIGSe solar cells and examples for nanoparticle fabrication techniques together with their chances and challenges for application to CIGSe will be presented. Particular attention will be paid to nanostructures that have been applied to CIGSe solar cells, revealing many theoretical and some experimental results. Metallic and dielectric nanostructures as well as intrinsic nanotextures will be covered. For the future, combined considerations of optical and electrical properties will gain in importance.
Integrating Geospatial Technologies to Examine Urban Land Use Change: A Design Partnership

Abstract This article describes a design partnership that investigated how to integrate Google Earth, remotely sensed satellite and aerial imagery, with other instructional resources to investigate ground cover and land use in diverse middle school classrooms. Data analysis from the implementation study revealed that students acquired skills for identifying and interpreting features in remotely sensed images and were able to identify distribution patterns of major land use types in urban areas. Specific instructional strategies and techniques, including direct instruction, coaching, and modeling how to think about analyzing land use patterns, appear to have assisted diverse learners in developing certain spatial thinking skills.
Experimental Study on the Influence of Dune Dimensions on Flow Separation

AbstractUsing laboratory experiments and a numerical model, this study examined the influence of dune dimensions on the separation of flow. Different conditions, depending on the dune height, material, and angle and flow depth and velocity, were considered. Experiments were conducted in a horizontal flume with one side wall being transparent for application of optical measuring devices. A train of two-dimensional (2D) fixed dunes were installed on the bottom of the flume starting just downstream of the entrance on the flume. Dunes were prepared with well-sorted gravel particles. Experiments were carried out using four types of dunes with different lee slopes. The numerical model used was sediment simulation in intakes with multiblock option (SSIIM), which is an open-source computational fluid dynamics model. Both experimental observations and numerical results were in agreement about the influence of dune characteristics on the flow separation, with particular regard to dune height, particle size, angle o.
New particle formation in Beijing, China: Statistical analysis of a 1‐year data set

[1] Particle number size distributions between 3 nm and 10 μm were measured in Beijing, China. New particle formation events were observed on around 40% of the measurement days from March 2004 to February 2005 and were generally observed under low relative humidity and sunny conditions. Though occurring during all seasons, new particle formation events had highest frequency in spring and lowest frequency in summer. Events were classified as “clean” or “polluted” groups mainly according to the condensational sink and the local wind. The formation rate range was from 3.3 to 81.4 cm−3 s−1. The growth rate varied from 0.1 to 11.2 nm h−1. The seasonal variation of condensable vapor concentration showed the highest values during summer months due to enhanced photochemical and biological activities as well as stagnant air masses preventing exchange with cleaner air.
Greenwich Time and the Discovery of the Longitude. Derek Howse. xviii + 254 pages, 15 × 21 cm, illustrated, Oxford University Press, 1980. £7.95.

Decca receiver and its operation is confused by the omission, from the linedrawing of the front panel, of the tenths digit from the lane identification display. (Drawings and their captions seldom seem to be proof-read as thoroughly as the text: one illustration in this book, concerning the NNSS, depicts a ship which appears to be beyond hope of aid from even the most sophisticated equipment.) Inevitably this book will be compared with the current English-language (jth) edition of G. J. Sonnenberg's Radar and Electronic Navigation, which covers much the same ground except that Sonnenberg includes a chapter on radar and refers only briefly to berthing aids. In general the two books complement each other. Appleyard has two years' advantage over Sonnenberg in this swiftly moving technology, and his treatment of Omega, for example, is correspondingly more up to date; his chapter on the terminology and mathematical expressions used in describing navigational errors fills a gap in the earlier publication. Sonnenberg, on the other hand, goes into more detail in describing how some of the systems work. A better title could perhaps have been chosen for this new and concise introduction to 'marine electronic navigation': 'Electronic Aids to Marine Navigation' would surely have been more fitting (the title of Sonnenberg's book is open to a similar criticism). Terminology is important, and by the same token it should be mentioned that both Appleyard and Sonnenberg make the mistake of describing the Loran-C slave stations as such, rather than as 'secondary' stations, which is the term used in United States Coast Guard publications. Claud Powell
Use of AVHRR data to verify a system for forecasting diurnal sea surface temperature variability

Abstract Forecasts from an operational system for predicting global diurnal sea surface temperature (SST) variability are compared against multichannel sea surface temperatures calculated from advanced very high resolution radiometer data from the NOAA-9 satellite. The forecast system consists of an upper-ocean model driven by heat fluxes and wind stresses from an operational global weather prediction model. Visual pattern correlations between observed and forecast diurnal changes in SST are generally favourable, indicating that the forecast system is useful. Some systematic deficiencies are also noted: the forecasts do not reproduce the surprisingly sharp boundaries of diurnal warming regions and underpredict the amplitude of the extreme warming events
Heat flow in the Mariana Marginal Basin

Twenty-one new heat flow measurements in the Mariana Trough delineate a central zone of high heat flow corresponding to an axial topographic high and a flank zone of low heat flow. The high heat flow is an indication that the axial high is a narrow zone of magmatlc intrusion and that sea floor spreading is occurring in the Mariana Trough in a manner similar to its occurrence on midocean ridges. The low heat flow values appear to be the result of the occurrence of hydrothermal circulation in the oceanic crust of the Mariana Marginal Basin.
Contribution of continental water to sea level variations during the 1997–1998 El Niño–Southern Oscillation event: Comparison between Atmospheric Model Intercomparison Project simulations and TOPEX/Poseidon satellite data

[1] Satellite altimetry from TOPEX/Poseidon (T/P) is used to estimate the variation of the global sea level. This signal, once corrected for steric effects, reflects water mass exchange with the atmosphere and land reservoirs (mainly ice caps, soils and snowpack). It can thus be used to test the capacity of general circulations models (GCMs) to estimate change in land water storage. In this study, we compare the land hydrology contribution to global mean sea level variations during the major 1997–1998 El Nino–Southern Oscillation event from two data sets: (1) the results of the Organizing Carbon and Hydrology In Dynamic Ecosystems (ORCHIDEE) land surface scheme, developed at the Institute Pierre Simon Laplace, coupled to the Laboratoire de Meteorologie Dynamique Atmospheric General Circulation Model (LMD AGCM) and (2) the T/P-based estimates. We show that the seasonal variation of the continental water storage is well represented in the model. The drastic amplitude change between the two contrasted years, 1997 and 1998, observed from satellite altimetry, is also simulated. We analyze the role of each component of simulated water fluxes (precipitation, evaporation, and runoff) in determining the range of annual continental water mass variation and its interannual variability. The difference between the two years, 1997 and 1998, is, for an essential part, due to land precipitation in the 20°N–20°S domain. This analysis emphasizes the important role of tropical regions in interannual variability of climate.
Moisture flux and mixing processes in the daytime continental convective boundary layer

This study is used to introduce a conditional sampling technique associated with a heuristic model of the convective boundary layer (CBL) based upon top-down, bottom-up physical processes. A new concept of a distribution of neutral buoyancy levels associated with those two classes of physical processes is included in the CBL model. Analysis of surface, aircraft, and sounding data from June 6, 1987, during FIFE showed two periods of drying in an otherwise moistening fair weather CBL with 7 to 9 ms−1 southerly winds. One period was during the so-called morning boundary layer transition, when the mixed layer was growing rapidly and the other during quasi-steady state afternoon conditions. Similar drying periods were observed on June 1 and 4. On June 6, however, morning and afternoon National Center for Atmospheric Research King Air missions were specifically designed to investigate time variations in the daytime CBL. The conditional sampling technique and the CBL model are used to investigate the composition of the moisture flux and flux divergence. We conclude that the drying effect of strong surface thermals carrying upward moving moist air was substantially decreased by overturning thermals and that compensating downdrafts were the dominant process associated with the net positive flux divergence responsible for part of the observed drying during the morning transition. The remainder was inferred to be due to a combination of vertical and horizontal advection. By afternoon drying due to compensating downdrafts had ceased and was due entirely to advection mitigated by turbulent processes which were moistening the mixed layer. The drying and inversion rise were coupled phenomena that were due to moist surface thermals which penetrated a weak lower inversion into an elevated mixed layer (EML). The EML was left from the previous day, and was well below a much stronger capping inversion. This penetrative convection into the EML suddenly removed moisture from the lower part of the mixed layer, moistened the region of the EML, and dried a growing mixed layer.
Some SH‐wave seismic reflections from depths of less than three metres

Shallow SH‐wave reflections are far from routine, although their study can provide insights into important properties of near‐surface materials that cannot be inferred from P‐wave data alone. Difficulties in separating SH‐wave reflections from Love waves are generally considered the major obstacle to progress in shallow SH‐wave seismic reflection. This may be the case in surveys undertaken at great depths, but it is not necessarily true for reflection data gathered at shallow and ultra‐shallow depths. This paper shows that when SH‐wave data possess wavelengths greater than the thickness of the superficial layer, Love waves are not greatly dispersed. In this case, misinterpretation between parts of reflection hyperbolae and waveguide arrivals is sufficiently limited. In a one‐layer model earth, which well approximates typical situations of the near‐surface underground, the most energetic modes (the lowermost modes) of the dispersed surface waves have a dominant frequency band that falls below the wavelet spectrum of the shallow reflections; therefore, they can be filtered out in the frequency domain. Higher modes, although their spectral content overlaps that of the reflections, exhibit small amplitudes on seismograms and leave strong reflections unaffected.We present field examples from three different sites where we were able to obtain ultra‐shallow reflections (< 3 m) in unconsolidated sediments. The high level of resolution (vertical resolution up to 15 cm) suggests that SH‐wave reflection imaging has the potential to complement other high‐resolution techniques, such as P‐wave reflection and ground‐penetrating radar (GPR) imaging, allowing a better and more complete characterization of the near‐surface environments.