Miracle-dz/UniFAR-FTUs huggingface dataset:
Application of waveform tomography to marine seismic reflection data from the Queen Charlotte Basin of western Canada

To obtain a higher resolution quantitative P-wave velocity model, 2D waveform tomography was applied to seismic reflection data from the Queen Charlotte sedimentary basin off the west coast of Canada. The forward modeling and inversion were implemented in the frequency domain using the visco-acoustic wave equation. Field data preconditioning consisted of f-k filtering, 2D amplitude scaling, shot-to-shot amplitude balancing, and time windowing. The field data were inverted between 7 and 13.66 Hz, with attenuation introduced for frequencies ≥ 10.5 Hz to improve the final velocity model; two different approaches to sampling the frequencies were evaluated. The limited maximum offset of the marine data (3770 m) and the relatively high starting frequency (7 Hz) were the main challenges encountered during the inversion. An inversion strategy that successively recovered shallow-to-deep structures was designed to mitigate these issues. The inclusion of later arrivals in the waveform tomography resulted in a veloci.
Observed Tropospheric Biennial Variability and Its Relationship to the Southern Oscillation

Abstract Tropospheric biennial variability in several components of the Southern Oscillation (SO) is defined and described through analysis of observational data from the Comprehensive Ocean-Atmosphere Data Set (COADS), as well as through investigation of several SO index time series. The analysis suggests that the temporal behavior of the SO can be described in terms of three components: 1) a pervasive biennial pulse, which appears to be strong in both the Indian Ocean and the west Pacific surface zonal winds as well as in several SO indices, 2) the annual cycle, which tends to set the phase of biennial variability for the major SO excursions, and 3) a low-frequency, or residual, variability, which may be associated with temporal scales between large SO episodes. This study also supports recent papers in suggesting that complete models of the SO must include the Indian Ocean basin.
Development of Integrated Sediment Rating Curves Using ANNs

Correct estimation of sediment volume being carried by a river is very important for many water resources projects. Conventional sediment rating curves, however, are not able to provide sufficiently accurate results. Artificial neural networks (ANNs) are a simplied mathematical representation of the functioning of the human brain. Three-layer feed-forward ANNs have been shown to be a powerful tool for input-output mapping and have been widely used in water resources problems. The ANN approach is used to establish an integrated stage-discharge-sediment concentration relation for two sites on the Mississippi River. Based on the comparison of the results for two gauging sites, it is shown that the ANN results are much closer to the observed values than the conventional technique.
Using a multimedia tool to improve cardiac auscultation knowledge and skills

AbstractOBJECTIVE: Today’s medical school graduates have significant deficits in physical examination skills. Medical educators have been searching for methods to effectively teach and maintain these skills in students. The objective of this study was to determine if an auscultation curriculum centered on a portable multimedia CD-ROM was effective in producing and maintaining significant gains in cardiac auscultatory skills. DESIGN: Controlled cohort study PARTICIPANTS: All 168 third-year medical students at 1 medical school in an academic medical center. INTERVENTIONS: Students were tested before and after exposure to 1 or more elements of the auscultation curriculum: teaching on ward/clinic rotations, CD-ROM comprehensive cases with follow-up seminars, and a CD-ROM 20-case miniseries. The primary outcome measures were student performance on a 10-item test of auscultation skill (listening and identifying heart sound characteristics) and a 30-item test of auscultation knowledge (factual questions about auscultation). A subset of students was tested for attenuation effects 9 or 12 months after the intervention. RESULTS: Compared with the control group (1 month clinical rotation alone), students who were also exposed to the CD-ROM 20-case miniseries had significant improvements in auscultation skills scores (P<.05), but not knowledge. Additional months of clerkship, comprehensive CD-ROM cases, and follow-up seminars increased auscultation knowledge beyond the miniseries alone (P<.05), but did not further improve auscultation skills. Students’ auscultation knowledge diminished one year after the intervention, but auscultation skills did not. CONCLUSION: In addition to the standard curriculum of ward and conference teaching, portable multimedia tools may help improve quality of physical examination skills.
CLUSTERING ARTIKEL BERITA BERBAHASA INDONESIA MENGGUNAKAN UNSUPERVISED FEATURE SELECTION

Meningkatnya penggunaan internet telah memicu pertumbuhan dan pertukaran informasi menjadi jauh lebih pesat dibandingkan era sebelumnya. Volume berita elektronik berbahasa Indonesia semakin bertambah besar dan menyimpan informasi yang berharga di dalamnya. Pengelompokkan berita berbahasa Indonesia merupakan salah satu solusi yang dapat digunakan untuk mempermudah mencerna informasi penting yang ada di dalamnya. Clustering dapat digunakan untuk membantu menganalisis berita dengan mengelompokkan secara otomatis berita yang memiliki kesamaan. Pada text clustering terdapat suatu permasalahan yaitu adanya fitur – fitur yang berdimensi tinggi. Diperlukan metode Feature selection untuk mengurangi dimensi fitur ini. Feature selection memiliki kemampuan mengurangi dimensionalitas suatu data sehingga dapat meningkatkan performansi clustering. Ada beberapa pendekatan sebagai teknik dari implementasi feature selection, salah satunya adalah filter based feature selection. Pada penelitian ini, dilakukan analisis perbandingan metode feature selection antara Term contribution dan Document Frequency. Metode-metode feature selection tersebut diterapkan secara filter feature selection. Pada akhir pengujian, dapat dibuktikan bahwa metode Term contribution lebih baik daripada Document Frequency karena memperhitungkan frekuensi kemunculan term pada suatu dokumen dan jumlah dokumen yang dimiliki term tersebut, sehingga term yang terpilih adalah term yang khas atau bersifat diskriminator. Hal ini dapat meningkatkan performansi clustering dokumen berdasarkan precision dan entropy.
New Research on Urban Road Network Mode and Density Values

First, domestic and international literatures about road network density research were reviewed, and it was found that reasonable road network density had not been studied deeply enough. Then based on queuing theory, the road network density was analyzed from the perspective of improving travel efficiency and decreasing time-consumption. It is concluded that in the city center and other areas where congestion is likely, a high-density and one-way road network system would be more beneficial than the alternatives. In the suburbs and other areas with better traffic conditions, a relatively low-density and large-space road network system is more suitable. Finally, rational road network density values in urban central areas and other areas are recommended.
Comparison of microphysical modeling of polar stratospheric clouds against balloon‐borne and Improved Limb Atmospheric Spectrometer (ILAS) satellite observations

A size-segregated stratospheric aerosol model with detailed polar stratospheric cloud (PSC) microphysics has been developed to study the formation and evolution of PSCs. For comparison with satellite and balloon-borne observations, one-dimensional simulations have been performed in Esrange/Kiruna (67.93°N, 21.07°E), Sweden during the period of winter 1996/1997. The modeled proportions of PSCs are consistent with the observations of volume, number, size distributions, and extinction coefficients derived from the in situ balloon-borne optical particle counter and the Improved Limb Atmospheric Spectrometer (ILAS) satellite sensor, demonstrating the capability of the model to capture PSC events. Model simulations successfully reproduce three major PSC events in the period from January to February 1997. The model is able to produce particle size distribution and number densities typical of the field observations in the Arctic stratosphere. Large HNO 3 -containing particles with a median radius of 6 μm and number densities in the range of 10 -5 to 10 -3 cm -3 are predicted to occur over a broad range of altitudes. Model simulations suggest that the homogeneous nucleation mechanism of type Ia PSCs out of type Ib PSCs plays a critical role in the formation of large HNO 3 -containing particles. The present model shows good potential for interpreting and validating the balloon-borne and satellite observations.
Aerosol physical and optical properties and their relationship to aerosol composition in the free troposphere at Izaña, Tenerife, Canary Islands, during July 1995

Aerosol physical, optical, and chemical properties were measured at 2360 m above sea level over the Canary Islands during July 1995. Five aerosol size modes were observed. Nucleation aerosols 160 Mm−1 at relative humidities <30%. The lowest scattering was in air masses from the northwest whose aerosols were mostly pollutants. Air masses with North African mineral dust had the highest scattering. The mass scattering efficiency for dust was 0.50±0.10 m2 g−1 compared to 0.61 m2 g−1 at Barbados. Estimates of monthly mean scattering indicate dust accounts for 42 to 70% of total scattering. Soluble K+ in aerosols was strongly correlated with total scattering during both dusty and nondusty periods regardless of source. The back- to total scattering ratio was essentially constant during the dusty and nondusty sampling periods, 0.138±0.013 and 0.144±0.005. Angstrom exponents ranged from 1.0 to 2.1 during the nondusty period and −0.12 to 0.72 during the dusty period. The estimated single scattering albedo appeared higher during the dusty period than during the nondusty period, suggesting mineral dust to be more cooling at 550 nm than pollutants.
Systèmes de production rizicole et maladies parasitaires dans l'Afrique de l'Ouest: caractéristiques socio-économiques des ménages agricoles en zone de forêt ivoirienne

This study is the continuation of a study led in the savannah area. Its purpose is to describe the economic situation of households subject to malaria risk in Cote d'Ivoire forested region, so as to provide economic indicators which could eventually help explain the expected differences in malaria morbidity. A survey was conducted beside a sample of nearly 800 rural households concerned by three different farming systems (inland valleys without rice cultivation, inland valleys with no or partial water control suitable for one annual rice crop, and inland valleys with full or partial water control suitable for two rice crops per year). This survey allowed to collect economic data such as the different cultivated crops, incomes and malaria prevention expenditures. Monetary economy is based on coffee and cocoa; rice and cassava being the main food crops. If some economic differences between the three agroecosystems were observed, those differences are not so great as in the savannah area and only concern revenues: value of property accumulation is low and quite similar in the three agroecosystems. Only 34% of families used bed nets and it was mainly for the family's head and his wife. Other means of protection against mosquitoes were used by 37% of the families. For those, the monthly average expenditure was about 1000 Fcfa.
Fibroblast Cultures and Dermatoglyphies : The Topology of Two Planar Patterns

This is a study of two, two dimensional biological patterns the pattern created in a confluent dish of normal fibroblast and the dermatoglyphic pattern on the primate palm and sole. Both patterns are characterised by a small repertory of different types of interruptions or discontinuities in fields of otherwise parallel aligned elements. Because these discontinuities are invariant under plastic deformations as well as rigid motions, a topological treatment is appropriate. A quantitative topological characterisation shows the pattern in the two systems to be essentially identical. Regarding both systems as exercises in packing elongated elements in the plane subject to certain constraints, both can be modelled by a smooth, planar, nonoriented vector field. In neither case can the development of pattern be accounted for solely in terms of the aggregate of autonomously arising local detail; the whole constrains and influences the local situations. The interrelationship of global and local constraints on packing is quantified by the index theorem, which accounts for the range of patterns that may develop. The study shows that to understand pattern development in these systems, it is necessary to include topological considerations in addition to an analysis of cell behaviour.
Subauroral electric fields and magnetospheric convection during the April, 2002 geomagnetic storms

We analyze the ionospheric electric fields during the geomagnetic storms of April, 2002 using data from the DMSP satellites. The subauroral potential drop (ΦSA) in the evening sector exceeded 60 kV at times and was often a substantial fraction of total cross‐polar‐cap potential drop (ΦPC). At storm commencement, the subauroral electric field penetration moved rapidly equatorward reaching the lowest magnetic latitude well before the end of the storms' main phases. ΦPC and ΦSA were correlated well with AE with no time delay. However, the correlations of ΦPC and ΦSA with Dst occurred with significant time delays, about an hour for ΦPC and longer for ΦSA. The largest values of ΦPC were seen near the end of the storm main phases while the largest values of ΦSA were seen well into the recovery phases. The results of this study have important implications on models attempting to describe the dynamics of the plasmasphere, the inner magnetosphere and the ring current.
In-situ evidence for a low degree of S-wave anisotropy in the oceanic upper mantle

A seismic refraction survey using ocean bottom seismometers with one vertical and two horizontal component geophones was carried out off western Canada. This report presents one feature of a comprehensive interpretation of the data set, that dealing with shear-wave velocity anisotropy in the uppermost mantle. Amplitude-and traveltime-corrected SV record sections for two profiles, EX2 approximately parallel to the spreading ridge and EX3 approximately parallel to the direction of spreading, were compiled. From an interpretation based on comparisons with synthetic seismograms, the shear wave velocity in the upper mantle is 4.5 km/s for EX2 and 4.6 km/s for EX3. The corresponding compressional wave velocities are 8.3 km/s and 7.5 km/s. The significant difference in P-wave velocities is attributed to azimuthal velocity anisotropy of the type normally found in the Pacific basin. In contrast, the small difference in S-wave velocities suggests a very low degree of shear wave anisotropy. The combination gives a prominent anisotropy in values of Poisson's ratio for the upper mantle, the first in-situ evidence for this feature. These results are consistent with laboratory measurements on ultramafic rock samples from ophiolite complexes.
Sea-level forcing of carbon isotope excursions in epeiric seas: implications for chemostratigraphy

Five new δ13C excursions are reported from the Upper Ordovician Galena Group of Iowa. The δ13Ccarb and δ13Corg trends are compared to sea-level trends based on conventional sedimentological and novel chemostratigraphic (eNd) methods. It is found that rising δ13C values occur during rising sea level, peak-magnitude δ13C values are coincident with inferred peak flooding, and declining δ13C values occur with declining sea levels. The relationship to sea level is explained by a simple model of episodic flooding of the Galena platform by cool, oxygen-depleted, nutrient-rich, bottom waters originating from the Sebree Trough, which was itself connected to the nearby Iapetus Ocean. Flooding of the inner Galena shelf during sea-level transgressions caused local changes in the carbon isotope balance of inner shelf waters due to (1) locally increased primary productivity and organic carbon burial, (2) locally increased exchange of 13C-enriched dissolved inorganic carbon (DIC) with surrounding epeiric sea water masse.
Comparison of Nonlinear Filtering Techniques for Lunar Surface Roving Navigation

Leading up to the Apollo missions the Extended Kalman Filter, a modified version of the Kalman Filter, was developed to estimate the state of a nonlinear system. Throughout the Apollo missions, Potter's Square Root Filter was used for lunar navigation. Now that NASA is returning to the Moon, the filters used during the Apollo missions must be compared to the filters that have been developed since that time, the Bierman-Thornton Filter (UD) and the Unscented Kalman Filter (UKF). The UD Filter involves factoring the covariance matrix into UDUT and has similar accuracy to the Square Root Filter; however it requires less computation time. Conversely, the UKF, which uses sigma points, is much more computationally intensive than any of the filters; however it produces the most accurate results. The Extended Kalman Filter, Potter's Square Root Filter, the Bierman-Thornton UD Filter, and the Unscented Kalman Filter each prove to be the most accurate filter depending on the specific conditions of the navigation system.
Analysis of in situ hyperspectral data for nutrient estimation of giant sequoia

In this paper, we report some correlation analysis results between in situ hyperspectral data in the spectral range of approximately 350-900 nm and three foliage nutrient constituents. Two hundred and forty hyperspectral measurements were taken using a PSD1000 spectrometer at a giant sequoia plantation site in 1997. Foliage nutrient constituents (expressed in concentration, percentage of dry weight)-total nitrogen (TN), total phosphorus (TP) and total potassium (TK)-were measured from the same site. The potential of hyperspectral data for estimating foliage nutrient status was evaluated using univariate correlation and multivariate regression analysis methods with different types of predictors: original and the first-order derivative spectra, vegetation index (VI)-based, spectral position-based, area-based and principal component analysis (PCA)-based predictors. The eight VIs were constructed from the blue, green, red and near-infrared spectra bands; spectral position-based predictors consisted of parameters extracted from the blue, yellow and red edges, the green peak and the red well; area-based variables were calculated as the sum of the first derivative values at each of the three edges; and the PCA-based predictors were obtained from principal component transformation applied to the first derivative spectra of the three edges. Results showed that the best foliage nutrient prediction was obtained with the PCA-based predictors in four-term prediction models for all three nutrient constituents. In univariate correlation analysis, it seems that only two VIs RB ( R 760-850 / R 350-400 ) and NRB (( R 760-850 - R 350-400 )/( R 760-850 + R 350-400 )) may be employed to predict all three nutrient constituents ( p =0.01), and better R 2 values were obtained from the maximum first derivative spectra of blue edge and yellow edge and the spectral reflectance difference between green peak and red well for TN, TP and TK. The results obtained from the univariate analysis, however, indicate that the level of correlation between foliage nutrient concentrations and hyperspectral data is low. In fact for TN there existed rather low correlations with different types of variables. In general, the best univariate correlation results were obtained for TK, then TP, with TN the worst. For multiple regression with PCA-based predictors, the best results came from TN, then TK, while the worst was associated with TP.
Calcium Phosphate Biominerals

### Tissues and minerals On a quantitative basis, the most important of the calcium phosphates (Table 1⇓) is an apatite closely related to hydroxylapatite (HAP). This is better described as an impure carbonate-containing apatite (CO3Ap) and forms the inorganic component of bones and teeth. Table 1⇓ also includes calcium phosphates (including two pyrophosphates) that occur in pathological mineralizations and those that are used for the repair of mineralized tissues. Unlike the well-controlled process of normal mineralization in bones and teeth (see later), pathological mineralizations are usually poorly controlled with the result that several calcium phosphates may occur together. In addition, their crystallographic orientations are often random. View this table: Table 1. Occurrence of calcium phosphates. The solubility isotherms of the calcium phosphates in the system Ca(OH)2-H3PO4-H2O at 37°C are shown in Figure 1⇓. Monetite occurs in the phase diagram, although its occurrence in normal or pathological calcifications has never been confirmed, one contributing reason being that its nucleation and growth is more difficult than brushite under biological conditions, so brushite forms in preference, even though brushite is less stable. β-Ca3(PO4)2 is a high-temperature phase that does not precipitate directly in aqueous systems; however, it is sufficiently stable in water for a solubility product to be determined so that an isotherm can be calculated, which is the origin of the isotherm in Figure 1⇓. However, if the aqueous system contains Mg2+ (1 or 2 mmol/l), the solubility product of “Ca3(PO4)2” is dramatically reduced (more than a thousand-fold) with the result that the structurally related whitlockite can easily precipitate (Hamad and Heughebaert 1986, LeGeros et al. 1989). Fe2+ ions have a similar effect. Whitlockite has superficially the same X-ray diffraction (XRD) …
Snowy backgrounds enhance the absorption of visible light in forest canopies

The fraction of radiation absorbed in the canopy depends on the amount and angular distribution of the solar irradiance reaching the top of the canopy as well as the fraction of this irradiance that is transmitted through the canopy gaps and reflected back to the vegetation by the background. This contribution shows that the presence of snow on forest floors enhances the fraction of absorbed Photosynthetically Active Radiation (PAR). A global analysis of satellite‐derived products reveals that this enhancement affects evergreen and deciduous forests of the boreal zone. This snow‐related effect may usefully contribute to the photosynthesis process in evergreen forests especially during spring time when radiation conditions are marginal but other physiological constraints (such as temperature) permit the necessary biochemical functions to take place.