Miracle-dz/UniFAR-FTUs huggingface dataset:
Stochastic models with heteroskedasticity: a Bayesian approach for Ibovespa returns

Current research compares the Bayesian estimates obtained for the parameters of processes of ARCH family with normal and Student's t distributions for the conditional distribution of the return series. A non-informative prior distribution was adopted and a reparameterization of models under analysis was taken into account to map parameters' space into real space. The procedure adopts a normal prior distribution for the transformed parameters. The posterior summaries were obtained by Monte Carlo Markov Chain (MCMC) simulation methods. The methodology was evaluated by a series of Bovespa Index returns and the predictive ordinate criterion was employed to select the best adjustment model to the data. Results show that, as a rule, the proposed Bayesian approach provides satisfactory estimates and that the GARCH process with Student's t distribution adjusted better to the data.
Assessing the performance of structure‐from‐motion photogrammetry and terrestrial LiDAR for reconstructing soil surface microtopography of naturally vegetated plots

Soil microtopography is a property of critical importance in many earth surface processes but is often difficult to quantify. Advances in computer vision technologies have made image‐based three‐dimensional (3D) reconstruction or Structure‐from‐Motion (SfM) available to many scientists as a low cost alternative to laser‐based systems such as terrestrial laser scanning (TLS). While the performance of SfM at acquiring soil surface microtopography has been extensively compared to that of TLS on bare surfaces, little is known about the impact of vegetation on reconstruction performance. This article evaluates the performance of SfM and TLS technologies at reconstructing soil microtopography on 6 m × 2 m erosion plots with vegetation cover ranging from 0% to 77%. Results show that soil surface occlusion by vegetation was more pronounced with TLS compared to SfM, a consequence of the single viewpoint laser scanning strategy adopted in this study. On the bare soil surface, elevation values estimated with SfM were within 5 mm of those from TLS although long distance deformations were observed with the former technology. As vegetation cover increased, agreement between SfM and TLS slightly degraded but was significantly affected beyond 53% of ground cover. Detailed semivariogram analysis on meter‐square‐scale surface patches showed that TLS and SfM surfaces were very similar even on highly vegetated plots but with fine scale details and the dynamic elevation range smoothed out with SfM. Errors in the TLS data were mainly caused by the distance measurement function of the instrument especially at the fringe of occlusion regions where the laser beam intersected foreground and background features simultaneously. From this study, we conclude that a realistic approach to digitizing soil surface microtopography in field conditions can be implemented by combining strengths of the image‐based method (simplicity and effectiveness at reconstructing soil surface under sparse vegetation) with the high accuracy of TLS‐like technologies. Copyright © 2015 John Wiley & Sons, Ltd.
Three-Phase Hybrid Cascaded Multilevel Inverter Using Topological Modules With 1:7 Ratio of Asymmetry

Asymmetrical cascaded topology can produce more number of levels. This can be further boosted by using level doubling networks (LDNs). An LDN is a floating capacitor fed two-switch topology that almost doubles the number of levels without necessitating any closed-loop control for the voltage balancing of the floating capacitors. Topological modules (TMs) are formed by using LDN. This paper shows the uniqueness of 1:7 ratio of asymmetry (between the TMs) to maximize the number of levels without having any loss in the intermittent voltage levels for the line-to-line voltage in a three-phase system. A new control technique to select the right space vector without generating any dc component in the output phase voltage is reported. Step-by-step description of the controller is presented in this paper. Extensive simulations using MATLAB/Simulink and supporting experimental results using a laboratory prototype have confirmed the usefulness of the proposed controller.
Synthetically Trained 3D Visual Tracker of Underwater Vehicles

We present a method for visually detecting and tracking the 3D pose of autonomous underwater vehicles, which aims to enable robust multi-robot convoying. We follow the approach of tracking-by-detection, which combines the robust, drift-free nature of object detection with the temporal consistency of tracking algorithms. Central to our method is a multi-output convolutional network that jointly predicts whether the target robot is present in the image (classification), the 2D bounding box around the target in the image plane, and the 3D orientation of the target. This, combined with camera intrinsic parameters and prior knowledge of the robot’s absolute scale, allows us to recover the full 6-degree-of-freedom pose (translation and orientation) of the target robot. To train our network, we use only synthetic images rendered using the Unreal game engine, which is a cost-effective way to produce a large training set without the need for laborious manual annotations. Our evaluation analyzes the impact of orientation offset on 3D detection accuracy, and demonstrates successful generalization of the learned model to real underwater photographs of the target robot.
An Economic Assessment of Low-Carbon Investment Flows in the U.S. Power Sector

This study used the GT NEMS model to analyze how the proposed federal regulation on carbon emissions will impact investments in the U.S. electricity generating capacity at the federal and Census Division level for 2016-2030. Results show that in order to reduce emissions by 32% by 2030, cumulative investments will increase from 399 to 414 billion USD by 2030. Under the scenario which addresses carbon leakage - covering new and existing power plants - cumulative investment will reach 475 billion USD by 2030. Addressing carbon leakage will affect not only the size of the investments but also the direction: when only existing power plants are covered investments in natural gas remains almost unchanged (123 billion USD) relative to the Reference case; while under the scenario that covers all power plants, investment in natural gas will be 24% lower and the investments in renewable will be 64% higher than the Reference. Carbon regulation will produce not only losers and winners among energy sources but also among U.S. states. While the South and Midwest states will experience much higher increase in cumulative investments with respect to the national average; Northeast and West states will reduce their overall investments by 2030 under the policy scenarios.
MORINGA OLEIFERA LEAVES: IMMUNOMODULATION IN WISTAR ALBINO RATS Research Article

This work has been carried out to find out immunomodulatory potential of leaves of Moringa oleifera (Family Moringaceae). The different extracts of leaves viz. Petroleum Ether (PEM), Chloroform (CHM), and Methanol (MEM) were administered at doses of 100, 200, and 400 mg/kg b.w, p.o. The measurement of immunomodulation was carried out in Wistar albino rats by Delayed Type Hypersensitivity (DTH), Humoral antibody (HA) titre, Cyclophosphamide induced myelosuppression, and T cell population tests. Results were compared with standard immunosuppressant drug Cyclophosphamide (30 mg/kg b.w, p.o) and standard immunomodulatory drug Levamisole (50 mg/kg b.w, p.o). Results of present study clearly indicate that PEM400 mg/kg and MEM at all doses shown potentiation of DTH response (p<0.01) after 24 hrs challenge. The increasing doses of methanolic extract have shown the augmentation of antibody titre (p<0.05). Cyclophosphamide induced immunosuppression was counteracted by MEM indicating restoration of hematological parameters (p<0.01). Groups treated with other extracts have shown restoration of hematological parameters as compared to Cyclophosphamide treated group but not regained the normal values. Above reports suggests that methanolic extract of Moringa oleifera leaves can stimulate both cellular and humoral immunity.
Seismic Characterization of Northeast Asia

Our project of seismic characterization of northeast Asia has continued on a multi-faceted approach concentrating on eastern Russia, including field deployments, data synthesis and interpretation, database integration, and travel-time tomography. For field efforts, we deployed four remote seismic stations in the Seimchan-Buyunda basin in the Magadan region to get a better idea of baseline seismicity. Several events per day were recorded over approximately 40 days of station operation; the detection threshold for events was an order of magnitude higher than that of base stations in the cities. Suspected faulting-related geomorphological features observed in satellite images were also field checked along the Ulakhan Fault, a major earthquake generating feature, in this area. Fault scarps and sag ponds were identified cutting across a major alluvial fan. These dramatic features were previously undocumented and represent part of a major, but poorly understood fault system. This fault likely represents ground truth locations of earthquakes in the area. For data analysis efforts, we completed interpretation of earthquake records from seismic stations deployed in the Stanovoi Range in 2006, including the determination of a composite focal mechanism. Other data analysis included extending our focal mechanism compilation of eastern Siberia to northeast Kamchatka, and analysis of seismicity and mechanisms in the Karaginsky Island area. Finally, we also updated focal mechanism and seismicity compilations for the Chersky Range. Our Siberia database enhancements for this past year include: (1) addition of new origin information for earthquakes and explosions (and associated phase data and amplitudes), from the Irkutsk, Yakutsk, and Magadan networks. , (2) additional catalog information from Siberia and the Far East in Russian language (Cyrillic) spread sheets covering years 1998-2004, and (3) and the inclusion of United States Geological Survey Earthquake Data Reports and International Seismological Centre magnitudes for larger events where Russian network operators did not report a K-class or a magnitude estimate. We have been using Pn, Pg, and Lg tomography to obtain crustal and upper-mantle velocities in northeast Asia. Pn velocities are higher beneath the Siberian Platform and generally lower under the tectonically active regions in the central and eastern portions of our study area. Pg velocities show a similar geographic trend, and our results agree closely with Pg results from earlier studies. Pg velocities beneath Sakhalin Island are anomalously low and we are working to understand this observation. Lg velocities are high beneath the Siberian Platform, the Chersky Range and the Verkhoyansk Foldbelt. Low Lg velocities are found beneath Sakhalin Island. In general, average Vp/Vs ratios of 1.73 to 1.75 are found throughout the study region. Travel-time correction surfaces will be developed from the tomographic maps, and these will be compared to correction surfaces currently being developed from the raw travel-time data.
Complex-Valued Restricted Boltzmann Machine for Speaker-Dependent Speech Parameterization From Complex Spectra

This paper describes a novel energy-based probabilistic distribution that represents complex-valued data and explains how to apply it to direct feature extraction from complex-valued spectra. The proposed model, the complex-valued restricted Boltzmann machine (CRBM), is designed to deal with complex-valued visible units as an extension of the well-known restricted Boltzmann machine (RBM). Like the RBM, the CRBM learns the relationships between visible and hidden units without having connections between units in the same layer, which dramatically improves training efficiency by using Gibbs sampling or contrastive divergence. Another important characteristic is that the CRBM also has connections between real and imaginary parts of each of the complex-valued visible units that help represent the data distribution in the complex domain. In speech signal processing, classification and generation features are often based on amplitude spectra (e.g., MFCC, cepstra, and mel-cepstra) even if they are calculated from complex spectra, and they ignore phase information. In contrast, the proposed feature extractor using the CRBM directly encodes the complex spectra (or another complex-valued representation of the complex spectra) into binary-valued latent features (hidden units). Since the visible-hidden connections are undirected, we can also recover (decode) the complex spectra from the latent features directly. Our speech representation experiments demonstrated that the CRBM outperformed other speech representation methods, such as methods using a conventional RBM, a mel-log spectrum approximate decoder, etc.
Extinction risk of North American seed plants elevated by climate and land‐use change

Summary Climate and land-use change are expected to substantially alter future plant species distributions leading to higher extinction rates. However, little is known about how plant species ranges, richness and phylogenetic diversity of continents will be affected by these dynamics. We address this gap here by examining the patterns of species' distributions and phylogenetic relationships for 7465 seed plant taxa in North America. An ensemble of species distribution models was used to estimate the potential suitable habitat of species under different sets of climate, land-use and dispersal constraint scenarios. We then evaluated the vulnerability and extinction risk of individual species to changes in climate and land use, and examined whether rare, endangered and evolutionarily distinct species were disproportionally threatened by climate and land-use change. We show that ~2000 species may lose >80% of their suitable habitats under the A1b emission scenario for the 2080s, while ~100 species may experience >80% range expansions (a 20 : 1 ratio of loss to gain). When considering >50% range retraction and expansion, the ratio of loss to gain was 13 : 1. A greater loss of species diversity is expected at low latitudes, while larger gains are expected at high latitudes. Evolutionarily distinct species are predicted to have significantly higher extinction risks than extant species. This suggests a disproportionate future loss of phylogenetic diversity for the North American flora. Synthesis and applications. Our study provides continental-scale evidence of plant species extinction risk caused by future climate and land-use change, and highlights the importance of integrating phylogenetic measures into conservation risk assessments. This work provides insight into the status, trends and threats for a large share of North America's plant species by identifying risks and prioritizing conservation in a rapidly changing world.
Evaluation of TRIS-DMA-NVP Hydrogels for Making Silicone-Based Contact Lenses

In this study, contact lenses were prepared through the polymerization of tris-(trimethyl-silyl-propyl-methacrylate) (TRIS), N,N-dimethylacrylamide (DMA), N-vinylpyrrolidone (NVP), and cross-linked with ethylene glycol dimethylacrylate (EGDMA). The equilibrium water content (EWC), oxygen permeability (Dk), light transmittance, and in vitro cytotoxicity of TRIS-DMA-NVP with various ratios were measured. The results showed that the EWC increased while the Dk decreased with the increase of NVP content. For the sample with 25 wt% NVP, the EWC attained 53% whereas the Dk decreased to 46 barrers. All these lenses exhibited light transmittance over than 95%. In addition, all these lenses exhibited no inhibition to the growth of L292 fibroblasts. Thus, this study showed that TRIS-DMA-NVP can be applicable for making contact lens. Keywords—DMA, TRIS, NVP, silicone hydrogel, contact lens.
Spectral statistics of non-Hermitian random matrix ensembles

Recently Burkhardt et al. introduced the [Formula: see text]-checkerboard random matrix ensembles, which have a split limiting behavior of the eigenvalues (in the limit all but [Formula: see text] of the eigenvalues are on the order of [Formula: see text] and converge to semi-circular behavior, with the remaining [Formula: see text] of size [Formula: see text] and converging to hollow Gaussian ensembles). We generalize their work to consider non-Hermitian ensembles with complex eigenvalues; instead of a blip new behavior is seen, ranging from multiple satellites to annular rings. These results are based on moment method techniques adapted to the complex plane as well as analysis of singular values.
Research on Synchronization and Adaptive Resource Allocation Algorithm in MIMO-OFDM System

With the development and applications of high-speed wireless communication techniques. Orthogonal Frequency Division Multiplexing (OFDM) techniques and Multiple Input and Multiple Output (MIMO) techniques have applied in broadband wireless communication system. Using robustness of OFDM technology to multi-path effects, MIMO technology can easily be applied to broadband wireless communications. We extend the synchronization algorithms for OFDM systems to MIMO-OFDM systems and a synchronization algorithm for MIMO-OFDM systems is proposed. It has nice estimation performance and no pilots are needed. On the research of adaptive power and bits allocation scheme in MIMO-OFDM system, an adaptive resource allocation algorithm is proposed. This algorithm is simple and practical. The simulation results suggest that the algorithm has good performance.
Relationship between aerodynamic roughness length and bulk sedge leaf area index in a mixed‐species boreal mire complex

Leaf area index (LAI) is an important parameter in natural ecosystems, representing the seasonal development of vegetation and photosynthetic potential. However, direct measurement techniques require labor‐intensive field campaigns that are usually limited in time, while remote sensing approaches often do not yield reliable estimates. Here we propose that the bulk LAI of sedges (LAIs) can be estimated alternatively from a micrometeorological parameter, the aerodynamic roughness length for momentum (z0). z0 can be readily calculated from high‐response turbulence and other meteorological data, typically measured continuously and routinely available at ecosystem research sites. The regressions of LAI versus z0 were obtained using the data from two Finnish natural sites representative of boreal fen and bog ecosystems. LAIs was found to be well correlated with z0 and sedge canopy height. Superior method performance was demonstrated in the fen ecosystem where the sedges make a bigger contribution to overall surface roughness than in bogs.
Structure and Properties of Coatings Made with Self Shielded Cored Wire

The welding technologies are widely used for design of protection layer against wear and corrosion. Hardfacing, which is destined for obtaining coating s with high hardness, takes special place in these technologies. One of the most effective way of hardfacing is using self shielded flux cored arc welding (FCAW - S). Chemical composition obtained in flux cored wire is much more rich in comparison to this obt ained in solid wire. The filling in flux cored wires can be enriched for example with the mixture of hard particles or phases with specified ratio, which is not possible for solid wires. This is the reason why flux cored wires give various possibilities of application of this kind of filler material for improving surface in mining industry, processing of minerals, energetic etc. In the present paper the high chromium and niobium flux cored wire was used for hardfacing process with similar heat input. The work presents studies of microstructures of obtained coatings and hardness and geometric properties of them. The structural studies were made with usi ng optical microscopy and X - ray diffraction that allowed for identification of carbides and other phases obtained in the structures of deposited materials. Investigated samples exhibit differences in coating structures made with the same heat input 4,08 kJ/mm. There are differences in size, shape and distribution of primary and eutectic carbides in structure. These differences cause significant changes in hardness of investigated coatings.
Board Interlocks and Earnings Management Contagion

ABSTRACT: We test whether earnings management spreads between firms via shared directors. We find that a firm is more likely to manage earnings when it shares a common director with a firm that is currently managing earnings and is less likely to manage earnings when it shares a common director with a non-manipulator. Earnings management contagion is stronger when the shared director has a leadership or accounting-relevant position (e.g., audit committee chair or member) on its board or the contagious firm's board. Irregularity contagion is stronger than error contagion. The board contagion effect is robust to controlling for endogenous matching of firms with directors, fixed firm/director effects, incidence of MA M41; M49; G34; G39; D83. Data Availability: Data are available from.
Seismic risk assessment of spatially-distributed systems using ground-motion modelsfitted considering spatial correlation

Ground-motion models are commonly used in earthquake engineering to predict the probability distribution of the ground-motion intensity at a given site due to a particular earthquake event. These models are often built using regression on observed ground-motion intensities, and are fitted using either the one-stage mixed-effects regression algorithm proposed by Abrahamson and Youngs (1992) or the two-stage algorithm of Joyner and Boore (1993). In their current forms, these algorithms ignore the spatial correlation between intraevent residuals. Recently, Jayaram and Baker (2010a) and Hong et al. (2009) observed that considering spatial correlation while fitting the models does not impact the model coefficients that are used for predicting median ground-motion intensities, but significantly increases the variance of the intra-event residual and decreases the variance of the inter-event residual. These changes have implications for risk assessments of spatiallydistributed systems, because a smaller inter-event residual variance implies lesser likelihood of observing large ground-motion intensities at all sites in a region. This manuscript explores the impact of considering spatial correlation on the ground-motion model in situations where the models are fitted using only a few recordings or closely-spaced recordings, which is often the case in low to moderately seismic regions such as the eastern United States. This is done by quantifying the changes to the variances of the inter-event and the intra-event residual in a variety of situations where the models are fitted using earthquakes with a small to moderate number of recordings that are separated by short to medium distances. It is seen that the changes to the variances of the residuals are more significant as the number of recordings per earthquake reduces, though the trend with the average station separation distance is not as clear. Finally, sample risk assessments are carried out for a hypothetical portfolio of buildings in order to illustrate the potential impact on the seismic risk of spatially-distributed systems. Overall, this work serves to illustrate the need to consider spatial correlation in the regression for ground-motion models in upcoming projects such as the NGA east project.