9,817 research outputs found
Nonlinear Exchange Rate Predictability
We study whether the nonlinear behavior of the real exchange rate can help us account for the lack of predictability of the nominal exchange rate. We construct a smooth nonlinear error-correction model that allows us to test the hypotheses of nonlinear predictability of the nominal exchange rate and nonlinear behavior on the real exchange rate in the context of a fully specified cointegrated system. Using a panel of 19 countries and three numeraires, we find evidence of nonlinear predictability of the nominal exchange rate and of nonlinear mean reversion of the real exchange rate. Out-of-sample Theil's U-statistics show a higher forecast precision of the nonlinear model than the one obtained with a random walk specification. Although the robustness of the out-of-sample results over different forecast windows is somewhat limited, we are able to obtain significant predictability gains--from a parsimonious structural model with PPP fundamentals--even at short-run horizons.Exchange rates; Predictability; Nonlinearities; Purchasing power parity
Hydrometallurgical extraction of Al and Si from kaolinitic clays
Herein is presented the results of a study on the hydrometallurgic extractionand recovery of aluminum and silicon by leaching of kaolinitic clays with HF. Thestudied extraction parameters were: temperature, reaction time, solid/liquid ratio,concentration, and precipitating agent mass. In the leaching process, mineraldissolutions near 100% were obtained when working at 348 K, solid/liquid ratio2% w/v, HF 12% v/v, for 120 minutes. The HF leach liquor generated from thedissolution of kaolinitic clays contains H2SiF6 and H3AlF6. Studies were conductedto recover the two valuable fluorides as K2SiF6 and Na3AlF6 by precipitation withalkaline salts from the leach liquor. Phases of precipitated fluorides were identifiedby XRD and surface morphology by SEM. The purity of the K2SiF6 precipitate was98.8%, whereas for Na3AlF6, it was 89.3%. Also, both synthesized solids are ofhigh commercial value due to their industrial applications.Fil: Pinna, Eliana Guadalupe. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Suarez, Daniela Silvana. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Universidad Nacional de Cuyo; ArgentinaFil: Rosales, Gustavo Daniel. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; ArgentinaFil: Rodriguez, Mario Humberto. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentin
Plantas y hongos tintóreos de los wichís del Gran Chaco
Se presentan los resultados de una investigación etnobotánica que trata los tintes vegetales y fúngicos entre los indígenas wichí del Chaco Semiárido. Se realizaron trabajos de campo con informantes calificados y ocasionales de ambos sexos en localidades de las provincias argentinas de Salta y Formosa. Asimismo, se hizo una revisión minuciosa de la bibliografía vinculada con el tema. Se encontraron 24 especies de plantas y 2 de hongos que son usadas para colorear productos textiles realizados a partir de fibras de cháguar (Bromelia hieronymi y B. urbaniana). Se proporcionan informaciones y detalles sobre los nombres vernáculos de las especies, las partes usadas, los procedimientos de tinción y los colores logrados. El número total de plantas tintóreas encontrado es alto comparado con los que fueron citados para otras etnias chaquenses y se registraron especies que antes no fueron mencionadas como tintóreas entre los wichís.Dye plants and fungi among the Wichí people of the Gran Chaco. This paper presents the results of an ethnobotanical investigation into plant and fungal dyes used by the Wichí people of the Semiarid Chaco. Fieldwork was carried out with occasional and key informants, both men and women, in several locations of Salta and Formosa provinces in Argentina. Moreover, a detailed examination of the bibliography on the topic was conducted. Twenty-four plant species and two fungi that are used for coloring textile products made from cháguar fibers (Bromelia hieronymi and B. urbaniana) were found. Information and details on the vernacular names of the species, the parts that are used, the dying technique and the colors obtained are provided. The total number of dye plants found is high compared with the ones cited among other Chaco ethnic groups, and records were made of species that had not previously been mentioned among the Wichí people as being used for dyes.Fil: Suarez, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Arenas Rodriguez, Pastor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentin
Theoretical analysis of REM-based handover algorithm for heterogeneous networks
© 2013 IEEE. Handover has been a widely studied topic since the beginning of the mobile communications era, but with the advent of another generation, it is worth seeing it with fresh eyes. Data traffic is expected to keep growing as new use cases will coexist under the same umbrella, e.g., vehicle-to-vehicle or massive-machine-type communications. Heterogeneous networks will give way to multi-tiered networks, and mobility management will become challenging once again. Under the current approach, based uniquely on measurements, the number of handovers will soar, so will the signaling. We propose a handover algorithm that employs multidimensional radio-cognitive databases, namely radio environment maps, to predict the best network connection according to the user's trajectory. Radio environment maps have been extensively used in spectrum-sharing scenarios, and recently, some advances in other areas have been supported by them, such as coverage deployment or interference management. We also present a geometric model that translates the 3GPP specifications into geometry and introduce a new framework that can give useful insights into our proposed technique's performance. We validate our framework through Monte Carlo simulations, and the results show that a drastic reduction of at least 10% in the ping-pong handovers can be achieved, thus reducing the signaling needed
Aportes del Gobierno en el Desarrollo de la Tecnología en los Diferentes Sectores de la Sociedad Nicaragüense durante el año 2007
En la actualidad nos encontramos en un país subdesarrollado en donde la tecnología sufre cambios con frecuencia, y sus avances van rumbo al desarrollo, ya que es implementada en los diferentes sectores, de acuerdo a las necesidades de la empresa ya sea del sector productivo, agropecuario, industrial y de servicio.
En nuestro país la tecnología se esta implementando en el sector industrial de zonas francas, proyecto que tiene como finalidad promover la tecnología, donde pretende construir gigantescos parques industriales, con maquilas sofisticadas.
Es por ello, que el gobierno esta ayudando a los avances tecnológicos que se proyectan en los diferentes sectores de la sociedad, ya que nos conduce a mejorar nuestro nivel de vida.
Las escuelas técnicas juegan un papel muy importante, ya que son las que cuentan con sus habilidades específicas, para la preparación de profesionales con capacidades técnicas para el manejo de equipos especializados. Es necesario que los centros de preparación, Universidades, Institutos también deben dar prioridad a la parte del desarrollo tecnológico.
Gracias a estos avances nuestro país va en vías de desarrollo tecnológico, ya que la tecnología, es una herramienta, de mucha importancia para la preparación de profesionales con capacidad y eficiencia.
Analizando la importancia de la tecnología en los distintos sectores de la Sociedad Nicaragüense, llegamos a la conclusión que es una herramienta, que ha venido a mejorar las capacidades técnicas, de las pequeñas y medianas empresas obteniendo mayores opciones en el mercado a través del uso de la tecnologí
CMOS-3D smart imager architectures for feature detection
This paper reports a multi-layered smart image sensor architecture for feature extraction based on detection of interest points. The architecture is conceived for 3-D integrated circuit technologies consisting of two layers (tiers) plus memory. The top tier includes sensing and processing circuitry aimed to perform Gaussian filtering and generate Gaussian pyramids in fully concurrent way. The circuitry in this tier operates in mixed-signal domain. It embeds in-pixel correlated double sampling, a switched-capacitor network for Gaussian pyramid generation, analog memories and a comparator for in-pixel analog-to-digital conversion. This tier can be further split into two for improved resolution; one containing the sensors and another containing a capacitor per sensor plus the mixed-signal processing circuitry. Regarding the bottom tier, it embeds digital circuitry entitled for the calculation of Harris, Hessian, and difference-of-Gaussian detectors. The overall system can hence be configured by the user to detect interest points by using the algorithm out of these three better suited to practical applications. The paper describes the different kind of algorithms featured and the circuitry employed at top and bottom tiers. The Gaussian pyramid is implemented with a switched-capacitor network in less than 50 μs, outperforming more conventional solutions.Xunta de Galicia 10PXIB206037PRMinisterio de Ciencia e Innovación TEC2009-12686, IPT-2011-1625-430000Office of Naval Research N00014111031
The Impact of COVID-19 on Students at USU Eastern
The COVID-19 pandemic has disrupted the lives of people throughout the world in numerous ways. The ramifications of the pandemic will be studied for years to come. We are interested in the effects the COVID-19 pandemic has had on college students, specifically those at Utah State University Eastern (USUE). We will be conducting an exploratory quantitative survey, in conjunction with the Student Counseling Center, for current students enrolled at USUE, ages 18 and above and will be asking questions about their mental, educational, financial, and social wellbeing. The survey will be distributed by email and will be available through the website Qualtrics. We plan on sharing our survey results with the Student Counseling Center along with other interested parties.https://digitalcommons.usu.edu/fsrs2021/1006/thumbnail.jp
Formation of oligopeptides in high yield under simple programmable conditions
Many high-yielding reactions for forming peptide bonds have been developed but these are complex, requiring activated amino-acid precursors and heterogeneous supports. Herein we demonstrate the programmable one-pot dehydration–hydration condensation of amino acids forming oligopeptide chains in around 50% yield. A digital recursive reactor system was developed to investigate this process, performing these reactions with control over parameters such as temperature, number of cycles, cycle duration, initial monomer concentration and initial pH. Glycine oligopeptides up to 20 amino acids long were formed with very high monomer-to-oligomer conversion, and the majority of these products comprised three amino acid residues or more. Having established the formation of glycine homo-oligopeptides, we then demonstrated the co-condensation of glycine with eight other amino acids (Ala, Asp, Glu, His, Lys, Pro, Thr and Val), incorporating a range of side-chain functionality
Repercussão de decisão do Supremo Tribunal Federal em ação direta de inconstitucionalidade sobre o sistema nacional do meio ambiente
Orientador: Jorge Madeira NogueiraMonografia (Especialização) - Universidade Federal do Paraná, Especialização em Direito AmbientalResumo: Esta monografia analisa a repercussão do Acórdão do Supremo Tribunal Federal ao apreciar ação direta de inconstitucionalidade contra artigo da Lei 9.985/2000 nos procedimentos adotados por entidades do Sistema Nacional do Meio Ambiente para definir o valor da compensação ambiental em processos de licenciamento de empreendimentos geradores de significativos impactos ambientais. Em particular, avaliam-se os procedimentos implantados a partir da decisão do Supremo para estimar o valor monetário de compensação ambiental. Para o levantamento das informações junto aos órgãos com competência para proceder ao licenciamento ambiental, definido o universo de pesquisa nas instituições estaduais e federal, foi elaborado formulário com perguntas fechadas. Conforme o pressuposto, os resultados obtidos indicaram limitação dessas organizações de cumprirem, ex tunc, as determinações do Tribunal Constitucional em função das limitações metodológicas que definam, com absoluto rigor científico e segurança jurídica, o exato valor a ser compensado monetariamente pelo empreendimento gerador de impacto ambiental significativo. Conclui-se propondo aplicação de métodos de valoração econômica de bens e serviços ambientais como a melhor técnica, considerados os limites e avanços do atual estado da arte das ciências ecológica e econômica, para observarem essa determinação lega
EDUCAÇÃO EM SAÚDE COMO ESTRATÉGIA DE ENFRENTAMENTO DA HIPERTENSÃO ARTERIAL SISTÊMICA.
Diversos fatores de risco podem influenciar o desenvolvimento das doenças crônicas, principalmente a Hipertensão Arterial Sistêmica (HAS), entre eles estão o consumo excessivo de sal na dieta, inatividade física, idade, obesidade, etc., potencializados pelos fatores condicionantes sócioeconômicos, culturais e ambientais. O conhecimento da doença está relacionado com à melhora da qualidade de vida, redução do número de descompensações e diminuição de internações hospitalares . Este estudo objetivou o desenvolvimento de ações educativas com hipertensos adultos da área de abrangência da ESF No. 6, CSSM-1, Município Santa Maria, DF, totalizando 82 usuários. A metodologia diz respeito a construção sistemática de estratégicas que analisou e considerou a população-alvo, o desenho do estudo, o plano amostral, as características sociodemográficas da população-alvo, os critérios de definição de hipertensão e a análise estatística. Quando então desenvolveu-se ações educativas com vistas ao autocontrole das doenças associadas a HAS, modificação de hábitos deletérios , promovendo o controle e consecutivamente diminuindo os fatores de riscos mais frequentes na comunidade. As taxas de prevalência mostram que cerca de 20% dos adultos apresentam hipertensão, sem distinção por sexo, mas também com evidente tendência de aumento com a idade. A intervenção educativa realizada foi eficaz no que se refere ao empoderamento dos pacientes sobre o risco de desenvolver hipertensão
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