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A Method of Characterizing Radio Signal Space for Wireless Device Localization

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Tsinghua Science and Technology 2015年第4期20卷 385-408页

作者： John-Austen francisco Richard P.Martin Department of Computer Science Rutgers University

In this work we present a novel approach for describing radio signal spaces for localization algorithms. We first introduce a new metric, the Discretely Distributed Log-H61der Metric （DDLHM）. The DDLHM is designed to characterize the type and degree of signal distortion relative to Iognormal signal-to-distance path models. We first show how the DDLHM can describe and discriminate distortions in an exhaustive set of synthetic signal spaces. We then determine a reduced set of maximally diagnostic distortion parameters. Using only 4% of the maximal set of DDLHMs, we found the reduced set matches with an acceptable degree of error 95% of the time. Using the synthetic reduced set, we characterized a variety of wireless localization algorithms＇ behaviors to attenuation, bias, and multipath. We found algorithms made much different tradeoffs between best case and average case error. We then use the DDLHM to identify distortion types in three different physical environments using measured 802.11 signal strengths, and predict the positioning performance of several localization algorithms. Our approach predicts average localization error to within 2 meters of the observed average error.

关键词： radio propgation 802.11 WiFi

Palm oil biodiesel:An assessment of PAH emissions,oxidative potential and ecotoxicity of particulate matter

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Journal of Environmental Sciences 2021年第3期33卷 326-338页

作者： Silvana Arias francisco Molina John R.Agudelo Grupo de Investigación en Gestión y Modelación Ambiental-GAIA Escuela AmbientalFacultad de IngenieríaUniversidad de Antioquia UdeACalle 70 No.52-21MedellínColombia Departamento de Ingeniería Mecánica Universidad de Antioquia UdeA

This work assessed the impact of fuelling an automotive engine with palm biodiesel(pure,and two blends of 10%and 20%with diesel,B100,B10 and B20,respectively)operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon(PAH)compounds,oxidative potential of ascorbic acid(OP^(AA)),and ecotoxicity through D aphnia pulex mortality *** diluted with filtered fresh air(WD)gathered in a minitunel,and particulate matter(PM)collected directly from the exhaust gas stream(W/oD)were used for *** showed that PM collecting method significantly impact PAH *** all PAH appeared in both,WD and W/oD,higher concentrations were obtained in the last *** biodiesel concentration in the fuel blend decreased all PAH compounds,and those with 3 and 5 aromatic rings were the most *** biodiesel affected both OP^(AA)and *** B10 and B20 exhibited the same rate of ascorbic acid(AA)depletion,B100 showed significant faster oxidation rate during the first four minutes and oxidized 10%more AA at the end of the test.B100 and B20 were significantly more ecotoxic than *** lethal concentration LC50 for B10 was 6.13 mg/*** was concluded that palm biodiesel decreased PAH compounds,but increased the oxidative potential and ecotoxicity.

关键词： Biodiesel Particulate matter P emissions Oxidative stress Ecotoxicity Daphnia pulex

Bi-objective mathematical model for choosing sugarcane varieties with harvest residual biomass in energy cogeneration

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International Journal of Agricultural and Biological Engineering 2012年第3期5卷 50-58页

作者： francisco Regis Abreu Gomes Coordination of Natural Resources Federal Institute of EducationScience and Technology of CearáRoad o f CedroQuixadáCEBrazil

Sugarcane crop occupies an area of about 23.78 million hectares in 103 countries,and an estimated production of 1.66 billion tons,adding to this volume more than 6%to 17%concerning residual biomass resulting from *** destination of this residual biomass is a major challenge to managers of *** are at least two alternatives which are reduction in residue production and increased output in electricity *** two conflicting objectives are mathematically modeled as a bi-objective *** study developed a bi-objective mathematical model for choosing sugarcane varieties that result in maximum revenue from electricity sales and minimum gathering cost of sugarcane harvesting residual *** approach used to solve the proposed model was based on theε-constraints *** were performed using real data from sugarcane varieties and costs and showed effectiveness of model and method *** experiments showed the possibility of increasing net revenue from electricity sale,i.e.,already discounted the cost increase with residual biomass gathering,in up to 98.44%.

关键词： sugarcane harvested residual biomass bi-objective mathematical programming ε-constraints method energy cogeneration

Diffusion dynamics and characterization of attogram masses in optically trapped single nanoparticles using laser-induced plasma imaging

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Nano Research 2023年第5期16卷 7470-7480页

作者： Pablo Purohit francisco J.Fortes Javier Laserna UMALASERLAB Departamento de Química AnalíticaUniversidad de MálagaC/Jiménez Fraud 4Malaga 29010Spain Niels Bohr Institute University of CopenhagenBlegdamsvej 172100 CopenhagenDenmark

In the present work,a wavelength-selected plasma imaging analysis system is presented and used to track photons emitted from single-trapped nanoparticles in air at atmospheric *** isolated nanoentities were atomized and excited into plasma state using single nanosecond laser *** use of appropriate wavelength filters alongside time-optimized acquisition settings enabled the detection of molecular and atomic emissions in the *** photon detection efficiency of the imaging line resulted in a signal>400 times larger than the simultaneously-acquired dispersive spectroscopy *** increase in sensitivity outlined the evolution of diverse physicochemical processes at the single particle scale which included heat and momentum transfer from the plasma into the particle as wells as chemical *** imaging detection of excited fragments evidenced different diffusion kinetics and time frames for atoms and molecules and their influence upon both the spectroscopic emission readout and fabrication processes using the plasma as a ***,the origin of molecular species,whether naturally-occurring or derived from a chemical reaction in the plasma,could also be studied on the basis of compositional gradients found on the *** of detection for the inspected species ranged from tens to hundreds attograms,thus leading to an exceptional sensing principle for single nanoentities that may impact several areas of science and technology.

关键词： single nanoparticle inspection wavelength-selected laser-induced plasma imaging laser fabrication attogram characterization atomic/molecular diffusion

Macrocystic serous cystadenoma of the pancreas

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Hepatobiliary & Pancreatic Diseases International 2019年第6期18卷 587-589页

作者： Patricia Pastor Pérez francisco Miguel González Valverde francisco Pastor Quirante Department of General Surgery Reina Sofia General University Hospital University of Murcia

Cystic pancreatic lesions are common,and about 90%of these lesions are pseudocysts or retention *** cysts of the pancreas are *** majority of pancreatic serous cystadenomas are *** serous cystadenoma is an unusual and essentially benign pancreatic *** radiologic features of this subtype may resemble a pseudocyst or a mucinous ***,it is often difficult to make a correct diagnosis[1,2].Herein,we report on a macrocystic serous cystadenoma of the pancreas in a 46-year-old female patient,with a preoperative diagnosis of pancreatic pseudocyst by radiologic imaging.

关键词： pancreas adenoma diagnosis

Personality Trait Detection via Transfer Learning

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Computers, Materials & Continua 2024年第2期78卷 1933-1956页

作者： Bashar Alshouha Jesus Serrano-Guerrero francisco Chiclana francisco P.Romero Jose A.Olivas Department of Information Technologies and Systems University of Castilla-La ManchaCiudad Real13071Spain Institute of Artificial Intelligence School of Computer Science and InformaticsDe Montfort UniversityThe GatewayLeicesterLE19BHUK

Personality recognition plays a pivotal role when developing user-centric solutions such as recommender systems or decision support systems across various domains,including education,e-commerce,or human ***-ditional machine learning techniques have been broadly employed for personality trait identification;nevertheless,the development of new technologies based on deep learning has led to new opportunities to improve their *** study focuses on the capabilities of pre-trained language models such as BERT,RoBERTa,ALBERT,ELECTRA,ERNIE,or XLNet,to deal with the task of personality *** models are able to capture structural features from textual content and comprehend a multitude of language facets and complex features such as hierarchical relationships or long-term *** makes them suitable to classify multi-label personality traits from reviews while mitigating computational *** focus of this approach centers on developing an architecture based on different layers able to capture the semantic context and structural features from ***,it is able to fine-tune the previous models using the MyPersonality dataset,which comprises 9,917 status updates contributed by 250 Facebook *** status updates are categorized according to the well-known Big Five personality model,setting the stage for a comprehensive exploration of personality *** test the proposal,a set of experiments have been performed using different metrics such as the exact match ratio,hamming loss,zero-one-loss,precision,recall,F1-score,and weighted *** results reveal ERNIE is the top-performing model,achieving an exact match ratio of 72.32%,an accuracy rate of 87.17%,and 84.41%of *** findings demonstrate that the tested models substantially outperform other state-of-the-art studies,enhancing the accuracy by at least 3%and confirming them as powerful tools for personality *** findings represent substantial a

关键词： Personality trait detection pre-trained language model big five model transfer learning

DEVELOPABLE SURFACE PATCHES BOUNDED BY NURBS CURVES

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Journal of Computational Mathematics 2020年第5期38卷 715-731页

作者： Leonardo Fernandez-Jambrina francisco Perez-Arribas ETSI Navales Universidad Polit´ecnica de Madrid28040-MadridSpain

In this paper we construct developable surface patches which are bounded by two rational or NURBS curves,though the resulting patch is not a rational or NURBS surface in *** is accomplished by reparameterizing one of the boundary *** reparameterization function is the solution of an algebraic *** the relevant case of cubic or cubic spline curves,this equation is quartic at most,quadratic if the curves are B´ezier or splines and lie on parallel planes,and hence it may be solved either by standard analytical or numerical methods.

关键词： NURBS B´ezier Rational,Spline NURBS Developable surfaces

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： francisco E Jorge José R da Costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

Real Renormings on Complex Banach Spaces

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Chinese Annals of Mathematics,Series B 2008年第3期29卷 239-246页

作者： francisco J GARC■A-PACHECO Alejandro MIRALLES Department of Mathematical Sciences Kent State University Departamento de Análisis Matemático Universidad de Valencia

The authors prove that every complex Banach space admits an equivalent real norm that is far away from being a complex norm. Furthermore, this real norm can be chosen to share many properties with complex norms, but i... 详细信息

关键词： Complex norms Real norms Hilbert space