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On the relation between Transversal and Longitudinal Scaling in Cities
Given that a group of cities follows a scaling law connecting urban population with socio-economic or infrastructural metrics (transversal scaling), should we expect that each city would follow the same behavior over time (longitudinal scaling)? This assumption has important policy implications, although rigorous empirical tests have been so far hindered by the lack of suitable data. Here, we advance the debate by looking into the temporal evolution of the scaling laws for 5507 municipalities in Brazil. We focus on the relationship between population size and two urban variables, GDP and water network length, analyzing the time evolution of the system of cities as well as their individual trajectory. We find that longitudinal (individual) scaling exponents are city-specific, but they are distributed around an average value that approaches to the transversal scaling exponent when the data are decomposed to eliminate external factors, and when we only consider cities with a sufficiently large growth rate. Such results give support to the idea that the longitudinal dynamics is a micro-scaling version of the transversal dynamics of the entire urban system. Finally, we propose a mathematical framework that connects the microscopic level to global behavior, and, in all analyzed cases, we find good agreement between theoretical prediction and empirical evidence
Optical Properties of Strained Graphene
The optical conductivity of graphene strained uniaxially is studied within
the Kubo-Greenwood formalism. Focusing on inter-band absorption, we analyze and
quantify the breakdown of universal transparency in the visible region of the
spectrum, and analytically characterize the transparency as a function of
strain and polarization. Measuring transmittance as a function of incident
polarization directly reflects the magnitude and direction of strain. Moreover,
direction-dependent selection rules permit identification of the lattice
orientation by monitoring the van-Hove transitions. These photoelastic effects
in graphene can be explored towards atomically thin, broadband optical
elements
Rejuvenescimento do cajueiro por meio de podas e substituição de copas.
Este trabalho teve como objetivo informar aos produtores de caju sobre as tecnologias para melhoria da cajucultura, tais como, rejuvenescimento de cajueiros antigos, substituição de copas por meio da eliminação seletiva de plantas...bitstream/item/80682/1/circular-44.PD
Transformer-based language models for semantic search and mobile applications retrieval
Search engines are being extensively used by Mobile App Stores, where millions of users world-wide use them every day. However, some stores still resort to simple lexical-based search engines, despite the recent advances in Machine Learning, Information Retrieval, and Natural Language Processing, which allow for richer semantic strategies. This work proposes an approach for semantic search of mobile applications that relies on transformer-based language models, fine-tuned with the existing textual information about known mobile applications. Our approach relies solely on the application name and on the unstructured textual information contained in its description. A dataset of about 500 thousand mobile apps was extended in the scope of this work with a test set, and all the available textual data was used to fine-tune our neural language models. We have evaluated our models using a public dataset that includes information about 43 thousand applications, and 56 manually annotated non- exact queries. The results show that our model surpasses the performance of all the other retrieval strategies reported in the literature. Tests with users have confirmed the performance of our semantic search approach, when compared with an existing deployed solution.info:eu-repo/semantics/acceptedVersio
Potencial de armazenamento de sementes de soja transgênica X convencional.
A soja Roundup Ready (RR) foi a primeira planta transgênica a ser aprovada para alimentação humana e animal para cultivo no Brasil. No caso da soja resistente ao glyphosate, a tolerância ao herbicida foi obtida pela inserção de um gene oriundo do genoma da Agrobacterium sp. Sob tratamento com esse herbicida, as plantas de soja não são afetadas, em virtude da ação continuada e sistemática dessa enzima alternativa, insensível ao produto. Porém, há relatos de decréscimo no potencial de armazenamento de sementes de soja transgênica, quando comparadas às convencionais. Neste trabalho o objetivo foi avaliar o potencial de armazenamento de sementes de variedades de soja transgênica (RR), comparativo a suas isolinhas não geneticamente modificadas. O potencial fisiológico (germinação e vigor - envelhecimento acelerado e emergência em areia) das variedades transgênicas foi analisado comparativamente com suas isolinhas em quatro períodos de armazenamento, com quatro repetições cada teste. As avaliações foram realizadas a cada dois meses. As variedades testadas foram BRS Valiosa RR e sua isolinha BR 46 Conquista; BRS 255 RR e BRS 137; BRS 245 RR e BRS 133. As variedades foram semeadas na mesma época e local, com o mesmo manejo cultural. Foi realizada capina manual, a colheita foi realizada em R7 e as plantas foram colocadas para secar a sombra. Após secas as vagens foram debulhadas manualmente. As sementes foram armazenadas em câmara refrigerada à temperatura de 18 ºC ± 2 ºC e 75% ± 4% de umidade relativa, até o momento da instalação dos experimentos. Não ocorreram variações nos potenciais de armazenamento entre as variedades transgênicas e suas isolinhas não geneticamente modificadas. O decréscimo do potencial fisiológico das sementes durante o armazenamento foi em função do qualidade inicial independente da variedade
The SASSCAL contribution to climate observation, climate data management and data rescue in Southern Africa
A major task of the newly established "Southern African Science Service Centre for Climate Change and Adaptive Land Management" (SASSCAL; www.sasscal.org) and its partners is to provide science-based environmental information and knowledge which includes the provision of consistent and reliable climate data for Southern Africa. Hence, SASSCAL, in close cooperation with the national weather authorities of Angola, Botswana, Germany and Zambia as well as partner institutions in Namibia and South Africa, supports the extension of the regional meteorological observation network and the improvement of the climate archives at national level. With the ongoing rehabilitation of existing weather stations and the new installation of fully automated weather stations (AWS), altogether 105 AWS currently provide a set of climate variables at 15, 30 and 60 min intervals respectively. These records are made available through the SASSCAL WeatherNet, an online platform providing near-real time data as well as various statistics and graphics, all in open access. This effort is complemented by the harmonization and improvement of climate data management concepts at the national weather authorities, capacity building activities and an extension of the data bases with historical climate data which are still available from different sources. These activities are performed through cooperation between regional and German institutions and will provide important information for climate service related activities
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