Miracle-dz/UniFAR-FTUs huggingface dataset:
An empirical model study of the tropospheric meridional circulation based on SAGE II observations

This study investigates the tropospheric mean meridional circulation important to the development of opaque clouds and the measurement opportunity of the 1.02-μm channel of the Stratospheric Aerosol and Gas Experiment (SAGE) II in the troposphere. A simple empirical model is formulated to derive the mean meridional circulation from the 6-year (1985-1990) statistics of the SAGE II tropospheric measurement frequency. The vertical circulation of the model is assumed to be related to the departure field of the zonally averaged SAGE II measurement frequency from the corresponding global mean in a linear fashion. The proportional constant is calibrated with the observed upwelling circulation statistics in the tropics. The obtained model vertical circulation is then used to determine the distribution of meridional velocity according to the continuity equation. The derived model mean circulation features the influence from both the diabatic circulation and the eddy quasi-isentropic transport, with a distinct pattern of material advection into the upper troposphere from both the lower troposphere and the stratosphere. Most significantly, the model circulation is shown to be highly consistent with the observed free tropospheric aerosol and ozone distributions, particularly with their seasonal variations given the aerosol and ozone source regions. This high degree of consistency illustrates the intimate relationship between the large-scale circulation, cloudiness, and the SAGE II tropospheric measurement frequency, and the robust nature of the empirical model despite the model's simplicity. The discussion in relating the model circulation to the conventional Eulerian circulation and the Lagrangian transport, based on isentropic consideration. is also provided.
Contribution of nitrogen species and phosphorus fractions to stream water quality in agricultural catchments

The contribution from agricultural catchments to stream nitrogen and phosphorus concentrations was assessed by evaluation of the chemical composition of these nutrients in agricultural runoff for both surface and subsurface flow pathways. A range of land uses (grazed and ungrazed grassland, cereals, roots) in intensive agricultural systems was studied at scales from hillslope plots (0.5 m2) to large catchment (>300 km2). By fractionating the total nutrient load it was possible to establish that most of the phosphorus was transported in the unreactive (particulate and organic) fraction via surface runoff. This was true regardless of the scale of measurement. The form of the nitrogen load varied with land use and grazing intensity. High loads of dissolved inorganic nitrogen (with >90% transported as NH4-N) were recorded in surface runoff from heavily grazed land. In subsurface flow from small (2 km2) subcatchments and in larger (>300 km2) catchments, organic nitrogen was found to be an important secondary constituent of the total nitrogen load, comprising 40% of the total annual load.
On Object-Orientation

Although object-orientation has been around for several decades, its key concept abstraction has not been exploited for proper application of object-orientation in other phases of software development than the implementation phase. We mention some issues that lead to a lot of confusion and obscurity with object-orientation and its application in software development. We describe object-orientation as abstract as possible such that it can be applied to all phases of software development.
Relationships between ozone and carbon monoxide at surface sites in the North Atlantic region

As part of the North Atlantic Regional Experiment (NARE), measurements of O3 and CO at five surface sites were made from July 1991 to January 1995. The investigation of the variabilities and correlation of O3 and CO presented here indicates that the seasonal cycles of the medians and the means of O3 and CO are qualitatively similar to the cycles observed at other northern midlatitude sites. The signature of O3 produced from anthropogenic precursors is clearest in the spring at the Azores and in the summer at Sable Island. The influence of the natural stratospheric O3 source is apparent at Sable Island, particularly in the spring. At all sites the variability of CO throughout the year is dominated by episodes of pollution transport. The slopes of the monthly O3-CO correlations in the summer in Atlantic Canada and the spring in the Azores are quite uniform at 0.3 to 0.4. However, individual pollution transport events often have larger (≤1.0) slopes, which indicate significantly different net O3 production efficiencies between episodes. The average slope of O3 versus CO at Sable Island in the winter for moderate pollution transport events (CO ≤180 ppbv) is −0.28, which indicates that the titration of ambient O3 by emitted NO with little if any photochemical O3 production dominates the O3 chemistry over eastern North America in winter. Diurnal cycles driven by photochemistry are observed in the summer for both O3 and CO at the Azores (net loss) and Sable Island (net production.) These observations are consistent with the work of Duderstadt et al. [this issue] who find positive net photochemical O3 production at Sable Island, and with the modeling of Atherton et al. [1996] who find a region dominated by photochemical loss of O3 and CO in the central Atlantic.
Spatial patterns of homogeneous pooling groups for flood frequency analysis

Abstract Several methods for the exploration and modelling of spatial point patterns are introduced to study the spatial patterns of homogeneous pooling groups for flood frequency analysis. The study is based on selected catchments in Great Britain, where a high density of gauging stations has been established. Initial pooling groups are formed using the K-means clustering algorithm with appropriately selected similarity measures. The pooling groups are subsequently revised to improve the homogeneity in the hydrological response. Spatial patterns of the initial and final pooling groups are explored in terms of intensity and dependence of the spatial distribution of the catchments. A test against a spatial point process is used to confirm or reject the initial impression of spatial clustering. Changes in the spatial patterns from the initial to the final pooling groups are examined using two comparison methods. The spatial pattern analysis described above can be used to answer the following questions: whether homogeneous catchments tend to exist in the vicinity of each other; whether the improvement in homogeneity tends to form more clustered pooling groups; and how the spatial patterns observed can be used to direct the selection of pooling variables.
The impact of digitalization on the strategies of pay TV in Spain

Introduction. The landscape of the audiovisual market has dramatically changed over the last thirty years, and even more so since the implementation of digital terrestrial television throughout Europe. New suppliers of audiovisual content have appeared and a range of pay-per-view and free-to-air services now compete against one another. Methodology. After all the changes, we wonder if there is still space for pay TV and how the strategy of pay TV operators might be developed. To do so, we will analyse current offerings according to three key factors: business models based on revenue and offering, clients, and competitors. Conclusions. After data analysis, we conclude that in spite of the threats to pay television operators, pay TV will be the engine of change, and the willingness to pay will increase. Most of the popular free-to-air contents, will become premium content.
Identifying the Building Blocks of Protein Structures from Contact Maps Using Protein Sequence and Evolutionary Information

— 1D protein sequences, 2D contact maps and 3D structures are three different representational levels of detail for proteins. The problem of protein 3D structure prediction from 1D protein sequences remains one of the challenges of modern bioinformatics. The main issue here is that it is computationally complex to reliably predict the full 3D structure of a protein from its 1D sequence. A 2D contact map has, therefore, been used as an intermediate step in this problem. A contact map is a simpler, yet representative, alternative for the 3D protein structure. In this paper, we focus on the problem of identifying similar substructural patterns of protein contact maps (the building blocks of protein structures) using a structural pattern matching approach that incorporates protein sequence and evolutionary information. These substructural patterns are of particular interest to our research, because they could potentially be used as building blocks for a computational bottom-up approach towards the ultimate goal of protein structure prediction from contact maps. The results are benchmarked using a large standard protein dataset. We assess the consistency and the efficiency of identifying these similar substructural patterns by performing different statistical analyses (e.g., Harrell-Davis Quantiles and Bagplots) on different subsets of the experimental results. We further studied the effect of the local sequence information, global sequence information, and evolutionary information on the performance of the method. The results show that both local and global sequence information are more helpful in locating short-range contacts than long-range contacts. Moreover, incorporating evolutionary information has remarkably improved the performance of locating similar short-range contacts between contact map pairs.
Nonparametric Tests for Common Values at First-Price Sealed-Bid Auctions

We develop tests for common values at first-price sealed-bid auctions. Our tests are nonparametric, require observation only of the bids submitted at each auction, and are based on the fact that the winner's curse' arises only in common values auctions. The tests build on recently developed methods for using observed bids to estimate each bidder's conditional expectation of the value of winning the auction. Equilibrium behavior implies that in a private values auction these expectations are invariant to the number of opponents each bidder faces, while with common values they are decreasing in the number of opponents. This distinction forms the basis of our tests. We consider both exogenous and endogenous variation in the number of bidders. Monte Carlo experiments show that our tests can perform well in samples of moderate sizes. We apply our tests to two different types of U.S. Forest Service timber auctions. For unit-price ( scaled') sales often argued to fit a private values model, our tests consistently fail to find evidence of common values. For lumpsum' sales, where a priori arguments for common values appear stronger, our tests yield mixed evidence against the private values hypothesis.
Rank/select operations on large alphabets: a tool for text indexing

We consider a generalization of the problem of supporting rank and select queries on binary strings. Given a string of length <i>n</i> from an alphabet of size σ, we give the first representation that supports <i>rank</i> and <i>access</i> operations in <i>O</i>(lg lg σ) time, and <i>select</i> in <i>O</i>(1) time while using the optimal <i>n</i> lg σ + <i>o</i>(<i>n</i> lg σ) bits. The best known previous structure for this problem required <i>O</i>(lg σ) time, for general values of σ. Our results immediately improve the search times of a variety of text indexing methods.
A reevaluation of the isostatic rebound of Lake Bonneville

Recent data pertaining to the uplift of the Provo and Bonneville shorelines of the late Pleistocene Lake Bonneville are evaluated in a reanalysis using a rigorous model of deformation of a plane earth comprising an elastic layer overlying a viscoelastic channel. The new observations constrain the wavelength and amplitude of the uplift of two shorelines formed at two different epochs, and they partly resolve the ambiguities in the plausible mechanical parameters found in previous solutions. The results indicate that the effective thickness of the elastic lithosphere is 28 to 30 km, equal to the seismically determined crustal thickness in the region. The estimate of the upper mantle viscosity in the region varies from (1.5–3.4) ×lO19 Pa s to (2.1–5.8)×l018 Pa s, depending on whether the upper mantle is assumed to be of uniform viscosity or the flow is confined to a narrow channel in the asthenosphere. The predicted rate of present uplift at the center of the desiccated lake is 0.06 mm/yr and 0.03 mm/yr for the shallow channel and uniform mantle models, respectively. These values are beyond the first-order leveling accuracies, and the question of the existence of a narrow channel in the region cannot be resolved with the available observations.
Revisions in Stratigraphic Nomenclature of the Columbia River Basalt Group

From abstract: New stratigraphic nomenclature for units within the Columbia River Basalt Group is introduced to revise and expand that currently in use; it is based largely on subdivisions made informally by T. L. Wright, M. J. Grolier, and D. A. Swanson in 1973. The Yakima Basalt is raised to subgroup status, and three formations-the Grande Ronde Basalt, Wanapum Basalt, and Saddle Mountains Basalt, in order of decreasing age-are defined within it.
Parametric Wavefield Decomposition And Applications

The problem of decomposing a multicomponent borehole seismic data set into its dominant P and S wavefields is formulated as a parametric inversion, where each (plane) wavefield is modelled by its Fourier components and by two frequency-independent parameters: apparent slowness and polarization angle. Modelling the data as the sum of a small number of plane waves, rather than as the sum of an implicitly large number as with 2D transform techniques, has the advantage that a small spatial aperture is required for estimation, thus affording greater spatial (vertical) resolution. The use of multicomponent data allows P and S wave polarization information to be included in the model, and it is shown how this added information serves to stabilize the inverse problem, effectively reducing sensitivity to aliasing. As well, nonlinear optimization for apparent slownesses and polarization angles permits estimation (assuming isotropic media) of medium velocity at receiver locations, so a priori knowledge of the velocity model is not necessary.
Tectonic tremor and deep slow slip on the Alpine Fault

Tectonic tremor is characterized by persistent, low‐frequency seismic energy seen at major plate boundaries. Although predominantly associated with subduction zones, tremor also occurs along the deep extension of the strike‐slip San Andreas Fault. Here we present the first observations of tectonic tremor along New Zealand's Alpine Fault, a major transform boundary that is late in its earthquake cycle. We report tectonic tremor that occurred on the central section of the Alpine Fault on 12 days between March 2009 and October 2011. Tremor hypocenters concentrate in the lower crust at the downdip projection of the Alpine Fault; coincide with a zone of high P‐wave attenuation (low Qp) and bright seismic reflections; occur in the 25–45 km depth range, below the seismogenic zone; and may define the deep plate boundary structure extending through the lower crust and into the upper mantle. We infer this tremor to represent slow slip on the deep extent of the Alpine Fault in a fluid‐rich region marked by high attenuation and reflectivity. These observations provide the first indication of present‐day displacement on the lower crustal portion of the Australia–Pacific transform plate boundary.
Fenología del anillo de crecimiento de Pinus uncinata Ramond y Pinus sylvestris L. en un gradiente altitudinal en los Pirineos Centrales

In this study, we describe tree-ring growth and structure of Pinus uncinata Ram. and Pinus sylvestris L. along an altitudinal gradient in the Central Pyrenees. We measured monthly ring width increase and the number of cells added during 1993. Both species formed most of the ring from mid june to mid July 1993. Latewood development -formation, darkening and lignification of cell walls- starts in July and ends in October. The ring begins before its development in P. sylvestris than in P. uncinata that lives at higher elevation. P. uncinata formed narrower rings with less cells and greater color heterogeneity in the latewood than P. sylvestris . There is a high variability between trees in the earlywood and latewood cells position in the ring. The different phenological patterns of tree-ring growth along the selected altitudinal gradient could be partially explained by the influence of different climatic conditions, mainly thermic.
Mapping the height and above‐ground biomass of a mixed forest using lidar and stereo Ikonos images

Our objective was to assess the accuracy of the forest height and biomass estimates derived from an Ikonos stereo pair and a lidar digital terrain model (DTM). After the Ikonos scenes were registered to the DTM with submetric accuracy, tree heights were measured individually by subtracting the photogrammetric elevation of the treetop from the lidar ground‐level elevation of the tree base. The low residual error (1.66 m) of the measurements confirmed the joint geometric accuracy of the combined models. Matched images of the stereo pair were then used to create a digital surface model. The latter was transformed to a canopy height model (CHM) by subtracting the lidar DTM. Plotwise height percentiles were extracted from the Ikonos‐lidar CHM and used to predict the average dominant height and above‐ground biomass. The coefficient of determination reached 0.91 and 0.79 for average height and biomass, respectively. In both cases, the accuracy of the Ikonos‐lidar CHM predictions was slightly lower than that of the all‐lidar reference CHM. Although the CHM heights did not saturate at moderate biomass levels, as do multispectral or radar images, values above 300 Mg ha−1 could not be predicted accurately by the Ikonos‐lidar or by the all‐lidar CHM.
Sensitivity of the Stratospheric Circulation to the Latitude of Thermal Surface Forcing

AbstractUsing the chemistry climate model Intermediate General Circulation Model–Fast Stratospheric Ozone Chemistry (IGCM-FASTOC), the authors analyze the response in the Northern Hemisphere winter stratosphere to idealized thermal forcing imposed at the surface. The forcing is a 2-K temperature anomaly added to the control surface temperature at all grid points within a latitudinal window of 10° or 30°. The bandwise forcing is applied systematically throughout all latitudes of the Northern Hemisphere. Thermal forcing applied anywhere equatorward of 20°N, or continuously from the equator to 30°N, increases planetary-wave generation in the troposphere and enhances the flux of wave activity propagating vertically into the stratosphere. Consequently, a greater flux of wave activity breaks in the polar vortex, increasing the Brewer–Dobson circulation and leading to a warm anomaly in the polar stratosphere. Ozone concentration increases at high latitudes and decreases at low latitudes. Thermal surface forcing .
Um Algoritmo Evolutivo para o Problema de Roteamento em Arcos Capacitados

O problema de roteamento em arcos capacitados (Capacitated Arc Routing Problem - CARP) consiste em visitar um subconjunto de arestas do grafo que descreve o problema, atendendo as suas demandas. Aplicacoes possiveis para o CARP sao a coleta de lixo urbano e a inspecao de linhas de forca. O CARP e um problema NP-dificil, mesmo no caso onde existe apenas um veiculo (chamado de Problema do Carteiro Rural). Neste caso, o uso de metaheuristicas surge como uma estrategia de solucao eficiente.Este trabalho apresenta um algoritmo genetico hibrido para o CARP, que e testado em instâncias disponiveis na literatura. Os resultados obtidos ate o momento demonstram a eficiencia do algoritmo proposto quando comparado com limites inferiores descritos na literatura.
Estimating Geostrophic Shear from Seismic Images of Oceanic Structure

It is shown that geostrophic vertical shear estimates can be recovered from seismic (i.e., acoustic) images of thermohaline structure. In the Southern Ocean, the Antarctic Circumpolar Current forms a loop within the Falkland Trough before it flows northward into the Argentine Basin. Seismic profiles that cross this loop show the detailed structure of different water masses with a horizontal resolution of O(10 m). Coherent seismic reflections are tilted in response to current flow around the Falkland Trough. Average slopes were measured on length scales that are large enough to ensure that the geostrophic approximation is valid (i.e., with a Rossby number <0.1). By combining shear estimates with satellite altimetric measurements and acoustic Doppler current profiles, geostrophic velocities can be calculated throughout the data volume. This technique for estimating geostrophic vertical shear from legacy seismic images yields useful information about the spatial and temporal variation of mesoscale circulation.
Trends in 20th century global rainfall interception as simulated by a dynamic global vegetation model: implications for global water resources

The Land‐surface Processes and eXchanges Dynamic Global Vegetation Model (LPX‐DGVM, one of several developments of the Lund–Potsdam–Jena (LPJ) model) is evaluated in terms of its interception component and used to simulate trends in 20th century global relative throughfall from natural vegetation. Mean global annual runoff is estimated to have been reduced by 163 ± 19 km3 year−1 between 1901 and 2006 as a result of biophysical changes controlling throughfall generation. Widespread decreases in relative throughfall of up to −1% are evident between the periods 1901–1953 and 1954–2006, while changes of up to −15% are shown in parts of North America and East Asia. Areas of simulated decrease in relative throughfall often lie in close proximity to areas of increase, reflecting the effects of vegetation shifts.
A three-channel algorithm for retrieving night-time land surface temperature from MODIS data under thin cirrus clouds

Thin cirrus clouds are dominated by non-spherical ice crystals with an effective emissivity of less than 0.5. Until now, the influences of clouds were not commonly considered in the development of algorithms for retrieving land-surface temperature (LST). However, numerical simulations showed that the influence of thin cirrus clouds could lead to a maximum LST retrieval error of more than 14 K at night if the cirrus optical depth (COD) at 12 μm was equal to 0.7 (cirrus emissivity equivalent to 0.5). To obtain an accurate estimate of the LST under thin cirrus using satellite infrared data, a nonlinear three-channel LST retrieval algorithm was proposed based on a widely used two-channel algorithm for clear-sky conditions. The variations in the cloud top height, COD, and effective radius of cirrus clouds were considered in this three-channel LST retrieval algorithm. Using Moderate Resolution Imaging Spectroradiometer (MODIS) channels 20, 31, and 32 (centred at 3.8, 11.0, and 12.0 μm, respectively) and the corresponding land surface emissivities (LSEs), the simulated data showed that this algorithm could obtain LSTs with root mean square errors (RMSEs) of less than 2.8 K when the COD at 12 μm is less than 0.7 and the viewing zenith angle (VZA) is less than 60°. In addition, a sensitivity analysis of the proposed algorithm showed that the total LST errors, including errors from the uncertainties in input parameters and algorithm error, were nearly the same as the algorithm error itself. Some lake surface water temperatures measured in Lake Superior and Lake Erie were used to test the performance of the proposed LST retrieval algorithm. The results showed that the proposed nonlinear three-channel algorithm could be used for estimating LST under thin cirrus with an RMSE of less than 2.8 K.