1,712 research outputs found

    Multi-LiDAR Mapping for Scene Segmentation in Indoor Environments for Mobile Robots

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    Nowadays, most mobile robot applications use two-dimensional LiDAR for indoor mapping, navigation, and low-level scene segmentation. However, single data type maps are not enough in a six degree of freedom world. Multi-LiDAR sensor fusion increments the capability of robots to map on different levels the surrounding environment. It exploits the benefits of several data types, counteracting the cons of each of the sensors. This research introduces several techniques to achieve mapping and navigation through indoor environments. First, a scan matching algorithm based on ICP with distance threshold association counter is used as a multi-objective-like fitness function. Then, with Harmony Search, results are optimized without any previous initial guess or odometry. A global map is then built during SLAM, reducing the accumulated error and demonstrating better results than solo odometry LiDAR matching. As a novelty, both algorithms are implemented in 2D and 3D mapping, overlapping the resulting maps to fuse geometrical information at different heights. Finally, a room segmentation procedure is proposed by analyzing this information, avoiding occlusions that appear in 2D maps, and proving the benefits by implementing a door recognition system. Experiments are conducted in both simulated and real scenarios, proving the performance of the proposed algorithms.This work was supported by the funding from HEROITEA: Heterogeneous Intelligent Multi-Robot Team for Assistance of Elderly People (RTI2018-095599-B-C21), funded by Spanish Ministerio de Economia y Competitividad, RoboCity2030-DIH-CM, Madrid Robotics Digital Innovation Hub, S2018/NMT-4331, funded by “Programas de Actividades I+D en la Comunidad de Madrid” and cofunded by Structural Funds of the EU. We acknowledge the R&D&I project PLEC2021-007819 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union NextGenerationEU/PRTR and the Comunidad de Madrid (Spain) under the multiannual agreement with Universidad Carlos III de Madrid (“Excelencia para el Profesorado Universitario’—EPUC3M18) part of the fifth regional research plan 2016–2020

    Current threats faced by amphibian populations in the southern cone of South America

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    In this work, we update and increase knowledge on the severity and extent of threats affecting 57 populations of 46 amphibian species from Chile and Argentina in southern South America. We analyzed the intrinsic conservation problems that directly impact these populations. We shared a questionnaire among specialists on threats affecting target amphibian populations with information on i) range, ii) historical occurrence and abundance, iii) population trends, iv) local extinctions, v) threats, and vi) ongoing and necessary conservation/research. We assessed association patterns between reported threats and population trends using multiple correspondence analysis. Since 2010, 25 of 57 populations have declined, while 16 experienced local extinctions. These populations were affected by 81% of the threat categories analyzed, with those related to agricultural activities and/or habitat modifications being the most frequently reported. Invasive species, emerging diseases, and activities related to grazing, ranching, or farming were the threats most associated with population declines. Low connectivity was the most frequent intrinsic conservation problem affecting 68% of the target populations, followed by low population numbers, affecting 60%. Ongoing monitoring activity was conducted in 32 (56%) populations and was the most frequent research activity. Threat mitigation was reported in 27 (47%) populations and was the most frequent ongoing management activity. We found that habitat management is ongoing in 5 (9%) populations. At least 44% of the amphibian populations surveyed in Chile and Argentina are declining. More information related to the effect of management actions to restore habitats, recover populations, and eliminate threats such as invasive species is urgently needed to reverse the conservation crisis facing amphibians in this Neotropical region.Fil: Kacoliris, Federico Pablo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: Berkunsky, Igor. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto Multidisciplinario de Ecosistemas y Desarrollo Sustentable; ArgentinaFil: Acosta, Juan Carlos. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Acosta, Rodrigo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Agostini, Maria Gabriela. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de EcologĂ­a, GenĂ©tica y EvoluciĂłn de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de EcologĂ­a, GenĂ©tica y EvoluciĂłn de Buenos Aires; ArgentinaFil: Akmentins, Mauricio SebastiĂĄn. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Arellano, MarĂ­a Luz. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: Azat, Claudio. Universidad AndrĂ©s Bello; ChileFil: Bach, Nadia Carla. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones BiolĂłgicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias FĂ­sico MatemĂĄticas y Naturales. Instituto Multidisciplinario de Investigaciones BiolĂłgicas de San Luis; ArgentinaFil: Blanco, Mirta Blanco. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Calvo, Rodrigo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: Charrier, Andres. Pontificia Universidad CatĂłlica de Chile; ChileFil: CorbalĂĄn, Valeria Elizabeth. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Correa, Claudio. Universidad de ConcepciĂłn. Facultad de Ciencias Naturales y OceanografĂ­a. Departamento de ZoologĂ­a; ChileFil: Cuello, Maria Elena. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; ArgentinaFil: Deutsch, Camila. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de EcologĂ­a, GenĂ©tica y EvoluciĂłn de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de EcologĂ­a, GenĂ©tica y EvoluciĂłn de Buenos Aires; ArgentinaFil: Di Pietro, Diego Omar. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: GastĂłn, MarĂ­a Soledad. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Gomez Alez, Rodrigo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Kaas, Camila. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: Kaas, Nicolas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: Lobos, Gabriel. Universidad de Chile; ChileFil: MartĂ­nez, TomĂĄs AgustĂ­n. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: MartĂ­nez Aguirre, TomĂĄs. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: Mora, Marta. Vida Nativa NGO; ChileFil: Nieva Cocilio, Rodrigo Alfredo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Pastore, HernĂĄn. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. AdministraciĂłn de Parques Nacionales; ArgentinaFil: PĂ©rez Iglesias, Juan Manuel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Luis. Instituto de QuĂ­mica de San Luis. Universidad Nacional de San Luis. Facultad de QuĂ­mica, BioquĂ­mica y Farmacia. Instituto de QuĂ­mica de San Luis; Argentina. Universidad Nacional de San Luis. Facultad de QuĂ­mica, BioquĂ­mica y Farmacia. Laboratorio de BiologĂ­a; ArgentinaFil: Piaggio Kokot, Lia Elena. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Rabanal, Felipe. Universidad Austral de Chile; ChileFil: RodrĂ­guez Muñoz, Melina JesĂșs. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Sanchez, Laura Cecilia. Provincia de Entre RĂ­os. Centro de Investigaciones CientĂ­ficas y Transferencia de TecnologĂ­a a la ProducciĂłn. Universidad AutĂłnoma de Entre RĂ­os. Centro de Investigaciones CientĂ­ficas y Transferencia de TecnologĂ­a a la ProducciĂłn. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Centro de Investigaciones CientĂ­ficas y Transferencia de TecnologĂ­a a la ProducciĂłn; ArgentinaFil: Tala, Charif. Ministerio del Medio Ambiente de Chile; ChileFil: Ubeda, Carmen Adria. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; ArgentinaFil: Vaira, Marcos. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Velasco, Melina Alicia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; ArgentinaFil: Vidal, Marcela. Universidad del Bio Bio. Facultad de Ciencias. Departamento de Ciencias Basicas; ChileFil: Williams, Jorge Daniel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. DivisiĂłn ZoologĂ­a de Vertebrados. SecciĂłn HerpetologĂ­a; Argentin

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð„with constraintsð ð ð„ „ ðandðŽð„ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

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    The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe

    Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks

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    A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV

    Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

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    Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

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    Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (Ό̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ÂŻ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ÂŻ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),Ό̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| &lt; 0.03 at 95% confidence level. [Figure not available: see fulltext.

    Measurement of the top quark mass using charged particles in pp collisions at root s=8 TeV

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    Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

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