bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Degradation of Amorphous PV Module Performance under Different Climatic Conditions
Authors: BENABDELKRIM Bouchra , Benatiallah Ali , GHAITAOUI Touhami ,   Department of Material Sciences, Institute of Science and Technology, University of Ahmed Draia, Adrar, Algeria.,   Laboratory of Energy, Environment and Systems of Information (LEESI), University Ahmed Draia Adrar, Algeria.,   Unité de Recherche en Energies Renouvelables en Milieu Saharien, URERMS, Centre de Développement des Energies Renouvelables, CDER, 01000, ADRAR, Algérie.
Published: June 2020

Usually, manufacturers provide PV panels, accompanied with data measured under Standard Test Conditions (STC), i.e. determined at AM1.5 with an irradiance of 1000W/m2 and a cell temperature equal to 25 C. In fact, these conditions do not reflect the reality of natural operation of PV panel conditions and these functional data associated with the real panel operating point may vary from one environment to another due to the change in weather conditions. The characterization of different types of PV panels under natural conditions of operation is, therefore, necessary in order to have a global view about the true electrical performance of different technologies at a given site. This work evaluates the influence of climatic conditions on the behavior of QS-60DGF module which has been installed at the Unit of Research in Renewable energy URERMS Adrar in the southern Algeria. The degradation evaluation of QS-60DGF module with different defects was performed, using (I-V/P-V) characteristics under daily weather conditions and the the visual inspection such as glass breakag. This study is to investigate the degradation rates of a-Si PV module after more than one year of outdoor exposure in desert conditions.
Contribution of the Doping of the Lower Window Layer to Improve the Performances of the Tandem Solar Cell
Authors: Fillali Mustafa , Dennai Benmoussa , Gani Abdennour ,   Laboratory of Renewable Energy Development and their Applications in the Saharan areas, Faculty of Exact Sciences, Tahri Mohammed University, Bechar, Algeria,   Laboratory of Renewable Energy Development and their Applications in the Saharan areas, Faculty of Exact Sciences, Tahri Mohammed University, Bechar, Algeria,   Magnetic materials laboratory. Djillali Liabes University Sidi Bel abbes, Algeria
Published: June 2020

Each layer of the tandem solar cell, its doping or its thickness, plays a primary task in improving the conversion efficiency. The optimization of the doping of the window layer of the lower solar cell of the tandem cell contributes to the reduction of the cost of the manufacture of its cells. The objective of this work is to show the role of doping the lower window layer on the performances of tandem CS in InGaP / GaAs with a tunnel heterojunction. For this a simulation is carried out using the Atlas-Silvaco simulator. It is specially designed for 2D and 3D modeling of components based on the physics of semiconductors, including electrical, optical and thermal properties The adapted structure is essentially composed of an upper cell in InGaP and a lower cell in GaAs. Between the two upper and lower cells, there is a heterojunction tunnel) P ++ N ++. The structure studied is composed of a thin window layer heavily doped with the materialIn0.629Al0.159Ga0.371P0.841 .Our simulation showed that, for an illumination of AM 1.5 and at room temperature, the parameters, such as the short-circuit current and the conversion efficiency, improve with the doping of the upper window layer.The best conversion efficiency is 24.2343% for a doping of 8x1018 cm-3.
Experimental Achievement and Improvement of Latent Heat Energy Storage Unit
Authors: GUELLIL Hocine , KORTI Abdel Illah Nabil ,   ETAP Laboratory, University of Tlemcen, 230, 13000,   ETAP Laboratory, University of Tlemcen, 230, 13000
Published: June 2020

Thermal energy storage systems by latent heat, in which phase change materials are used, are the subject of many scientific works. These systems are designed to guarantee the energy saving through promising technology. The present work concerns the experimental study of thermal performances of a latent heat thermal storage device made in our laboratory (ETAP). The PCM (paraffin) is stored in the vertical finned U-shaped tubes of the exchanger. The air is used as the heat transfer fluid. The storage unit use several identical heat exchangers filled with paraffin. The study examines the complete cycle with the two processes of charging (melting) and discharging (solidification) to analyse the effect of the numbers of exchangers on the thermal performance of the thermal storage. The obtained results showes that the storage unit with three exchangers stores 73 and 32% more thermal energy than a storage unit with one and two exchangers. At the end of the discharging duration, the first exchanger releases its total heat in Conf. 1, 2 and 3 respectively, after 126, 149 and 160 min
Modelling and Control of Photovoltaic System using the incremental conductance method for maximum power point tracking
Authors: Maatallah Elabbes , Berbaoui Brahim ,   Sciences of Technologie, Sciences & Technologie, University of Ahmed draya Adrar, Adrar, Algeria,   Unité de recherche en Energie Renouvelables en milieu saharien, URERMS, Centre de Développement des Energies Renouvelable, CDER, 01000, Adrar, Algeria
Published: June 2020

This paper presents the modeling and simulation of the electrical operation of a photovoltaic (PV) system. A DC-DC boost converter was chosen for the regulation of the output voltage at the peak power point while also providing a constant voltage. Maximum Power Point Tracker (MPPT) control that allows extraction of maximum available power from the photovoltaic (PV) panel has been included. The maximum efficiency is achieved when PV works at its maximum power point which depends on insolation and temperature. Since the insolation and temperature always change with time, a PV system which able to track the maximum power point needs to be developed to produce more energy. This research was aimed to explore the performance of a maximum power point tracking system which implements Incremental Conductance (IC) method. The IC algorithm was designed to control the duty cycle of Boost converter and to ensure the MPPT control work at its maximum efficiency. The simulation results obtained with Matlab / Simulink show the instantaneous oscillation of the operating point of the photovoltaic module around the MPP independently to weather changes, the proper functioning of the converter which provides a voltage at its output greater than that supplied by the PV generator, (a yield of the order of 90%) and the low power losses supplied by this module (less than 10%) allowed to conclude that the PV system simulated during this work was working properly and was satisfactory
21ST CENTURY TOURISM: THREATS AND OPPORTUNITIES
Authors: Aznar Mercedes
Published: June 2020

The good results of tourism in 2016 have raised optimism in the sector however, there is a series of threats that may have a negative significant impact on tourism if they are not paid the required attention. Also, avoiding seasonality and the risk of endangering small rural communities must be considered, as sustainability should be the main priority for all the stakeholders involved, especially this year when the whole world is celebrating the International Year of Sustainable Tourism for Development. Therefore, the objective of this paper is to make an analysis on those threats that can seriously damage the tourist sector but also, on the opportunities that may derive from the dramatic changes our society is going through. This study has been based on four particular areas: health tourism and accessibility; culture, gastronomy and wine; education and technology; and mountain tourism. There are many opportunities the sector can benefit from but only if the parties involved are willing to innovate and become creative.
TOURISM, ECOCULTURAL HERITAGE, DEVELOPMENT STRATEGIES AND TERRITORIAL VALORIZATION IN THE BORDER MOUNTAINS OF THE IBERIAN CENTRAL MOUNTAIN RANGE
Authors: Fernandes Gonçalo Poeta
Published: June 2020

The border of central Portugal with Castylla y Leon and Extremadura in Spain, combines ecocultural resources of great value. These should be articulated in a complementary way in an integrated territorial vision, reinforcing a wider market that, due to the differences and proximity, allow the construction of a composite tourist product. The perceptions of the past, associated with the constraints and barriers that these spaces represent, have been attenuated and present at the present time a greater relationship, through the approximations generated by the physical and technological communication routes, as well as by the forms of formal and informal cooperation developed. These territories, in addition to their natural value, represent their own ways of life, with systems of agricultural and forestry use, revealing a sustainable appropriation of the physical elements and their resources, allowing the construction of landscapes and ecosystems of ecoculture relevance, associated to the cultural heritage existing. At present, new opportunities are emerging as a result of tourism demand and its condition as international spaces of circulation. Mountain border areas, due to their patrimonial value and resources, require the coordination of efforts between the management entities and the various touristic actors.
DO ALL SEDENTARY BEHAVIORS AFFECT LIFE SATISFACTION EQUALLY IN STUDENTS AGED 12-16 YEARS?
Authors: Grao-Cruces Alberto , Nuviala Román , Aznar Cebamanos Mónica , Nuviala Alberto
Published: June 2020

Previous studies have proven the importance of life satisfaction for teenage development and its relationship with unhealthy behaviors. However, those that examined the association between sedentary behavior and life satisfaction were limited only to screen time. The aim of the study was examine the association of different sedentary behaviors with life satisfaction in 1897 Spanish students aged 12-16 years. Watching TV, using PC, and homework time, as well as life satisfaction were self-reported using validated questionnaires for these ages. We completed linear and logistic binary regression analyses adjusted by age and gender. The results showed that the time of TV watching and PC use were negatively associated to life satisfaction (ß = -.059 and ß = -.087, respectively) while the number of weekly hours devoted to homework was positively associated to life satisfaction (ß = .052). Moreover, the students who devoted greater time to sedentary behaviors in front of a TV or PC had significantly greater risk of low life satisfaction (OR = 1.276 and OR = 1.317, respectively). On the contrary, the teenagers who devoted more time to homework showed significantly lower risk of low life satisfaction (OR = .809). These results on Spanish students help to confirm the negative relationship of TV and PC abuse with life satisfaction in teenagers. Our findings also suggest that positive emotional responses during homework completion increase life satisfaction, while negative emotions during this behavior do not significantly damage it. In conclusion, life satisfaction could be improved with less screen time but not all sedentary behaviors affect it equally.
A indústria 4.0: uma análise comparativa entre as experiências da Alemanha, EUA, China, Coréia do Sul e Japão
Authors: Lucena Felipe Andrade , Roselino José Eduardo , Diegues Antonio Carlos
Published: June 2020

O artigo apresenta uma análise comparativa das políticas industriais das principais nações envolvidas na disputa tecnológica em torno da indústria 4.0 (Estados Unidos, Alemanha, China, Japão e Coréia do Sul).  As estratégias nacionais são analisadas a partir de um recorte transversal e multidimensional. Reforça-se o entendimento de que a gestação da indústria 4.0 deve ser compreendida a partir de abordagens que transcendam a dimensão tecnológica e integrem elementos de economia política e geopolítica. Para esse fim foi utilizada a metodologia de análise documental comparativa para a identificação dos aspectos distintivos das experiências nacionais selecionadas. Conclui-se que a emergência da indústria 4.0 não é um fenômeno meramente tecnológico nem muito menos espontâneo, mas resulta de esforços deliberados das economias centrais para fazer avançar a fronteira tecnológica em contraposição ao questionamento das lideranças produtiva e tecnológica por parte da China e conter, ainda que parcialmente, a sua afirmação como ator central do sistema econômico internacional.
Evidências sobre mudança estrutural, heterogeneidade estrutural e regional: uma análise da produtividade do trabalho brasileira no período 2004-2015
Authors: Souza Thais Andreia Araujo de , Vieira Marieli , Cunha Marina Silva da
Published: June 2020

Este estudo objetivou estudar a produtividade do trabalho brasileira (2004-2015) buscando quais unidades federativas e setores mais contribuíram para o baixo desempenho. Concluiu-se que há crescimento da produtividade, sendo verificado que a agropecuária possuiu menor nível e maior crescimento, e a região Nordeste possuiu menor nível também e maior crescimento. Também foi constatado que o baixo desempenho da produtividade decorreu principalmente da produtividade intrassetorial. Portanto, residiu na falta de crescimento dentro dos setores, e, a mudança estrutural contribuiu pouco para o desempenho, portanto, uma aceleração desse processo de mudança na estrutura produtiva beneficiaria a produtividade total. Ademais, conclui-se que existe heterogeneidade estrutural e regional no país.
A dinâmica das fronteiras e a migração haitiana contemporânea
Authors: Jesus Alex Dias de , Goettert Jones Dari
Published: June 2020

A antiga e intensa migração de haitianos pelo mundo ajudou a transformar o Haiti em uma sociedade transnacional, profundamente conectada com diversos destinos através das redes sociais entre migrantes e não migrantes. A partir de 2010, além da continuidade da migração para tradicionais destinos, os haitianos incorporaram países da América do Sul ao seu espaço migratório. Entretanto, as estratégias de mobilidade e atravessamento de fronteiras estão diretamente vinculadas às políticas migratórias adotadas pelos países de destino e de trânsito desses migrantes, contribuindo para a reconfiguração desses movimentos. Diante disso, o presente estudo objetivou analisar a relação entre a migração haitiana contemporânea e as políticas migratórias de alguns dos seus destinos. Para este fim, a metodologia utilizada baseou-se em revisão bibliográfica e documental publicada nos países que atualmente configuram-se como destinos dessa intensa mobilidade.
Análise da fragmentação da paisagem na região extremo Oeste Paulista, Brasil
Authors: Santos Carla Rodrigues , Rocha Paulo César
Published: June 2020

O conceito de estrutura da paisagem se refere ao estudo da paisagem a partir da medição e quantificação de seus aspectos estruturais e espaciais. O objetivo deste artigo é avaliar as métricas da paisagem no extremo Oeste Paulista, Brasil. Para isso, usamos informações de imagens de satélite e um Sistema de Informação Geográfica, a fim de identificar o grau de retalhamento e isolamento da paisagem. Como resultados temos que a área é recoberta por usos antrópicos, que representavam 73,92%, e o restante está distribuído em áreas naturais (área úmida, ilha e fragmentos florestais e corpos d'água). Ao analisarmos o índice de área, referente ao tamanho dos fragmentos, pudemos identificar que os maiores percentuais estão concentrados na pastagem (42,51%) e agricultura (28,58%). Os índices analisados confirmam que a fragmentação da paisagem é expressiva e sofre intensas perturbações.
Dinâmica da paisagem do planalto do rio Canoas (SC) no quaternário tardio com base em registros pedoestratigráficos de paleocabeceira de drenagem
Authors: Pagotto Dayane , Paisani Julio Cesar , Sordi Michael Vinicius de
Published: June 2020

O estudo da dinâmica quaternária das paisagens do sul do Brasil tem avançado, porém lacunas na escala mesolocal permanecem. A aplicação de descrições pedoestratigráficas, análise granulométrica, determinação de isótopos estáveis do carbono (ƍ13C), análise micromorfológica e o estabelecimento da geocronologia do registro estratigráfico permitiram estabelecer a morfodinâmica de paleocabeceira de drenagem no Planalto do rio Canoas durante o Quaternário Tardio. Essa unidade geomórfica apresenta, em sua maioria, registros pedoestratigráficos cronocorrelatos com outros identificados nas superfícies de cimeiras de Palmas/Caçador (PR-SC) e Vacaria (RS), sugerindo que sua dinâmica ambiental esteve em fases com condições paleoambientais de cunho regional detectadas do Último Interestadial ao Holoceno Superior.
Reaproveitamento da areia de formigueiro em fertilizante na horta escolar como contribuição ao ensino de geografia
Authors: Melo Cristiane E Castro Feitosa
Published: June 2020

Essa pesquisa tem como principal objetivo analisar a contribuição da experiência do reaproveitamento da areia de formigueiro em fertilizante na horta da escola pública, como contribuição ao ensino de geografia dos alunos do Ensino Fundamental. Trata-se de uma pesquisa qualitativa do tipo estudo de caso etnográfico. O trabalho está estruturado em duas partes. Na primeira – Conhecimento da ecologia para o exercício da cidadania - apresenta uma retrospectiva da educação ambiental na política global e escolar. Na segunda parte - A experiência do reaproveitamento da areia de formigueiro em fertilizante natural na horta da Escola Nilson Holanda – registra a experiência pedagógica desenvolvida em uma escola pública do município de Fortaleza. Por último, apresenta as considerações finais, discutindo a necessidade de uma tomada de consciência em relação à geografia em conjunto com a educação ambiental para fortalecer as ações humanas.
Clusters e sua adaptação às cadeias de valor global (CGVs)
Authors: Pereira Violeta De Faria , Galvão Cláudia Andreoli
Published: June 2020

A partir de 1970, a produção fragmentou-se internacionalmente, minimizando custos, deslocando para os países de mão de obra abundante e barata as fases da produção mais trabalho-intensivas. Intensificam-se as redes globais apoiadas nos transportes, telecomunicações e tecnologia da informação. Pesquisa e desenvolvimento, design, fabricação e distribuição, remodelaram a produção em CGVs, forçando os distritos industriais (DIs)/clusters a se adaptarem, mudarem, reinvestirem ou declinarem. Assim, via revisão bibliográfica, buscou-se responder à pergunta se os DIs/clusters perderiam ou ganhariam relevância na globalização. Os distritos italianos mudaram sua especialização de bens finais para bens de capital, com um terço das empresas se transferindo para a indústria mecânica em atividades correlatas, explorando suas conexões com as CGVs, coordenando fornecedores, se reorientando para produtos de alta qualidade, aumentando investimentos em marketing e marcas. No caso brasileiro com o processo de reestruturação os DIs/clusters abandonaram as estratégias de redução de custos e passaram a inovar, aumentando a importação de bens intermediários e utilizando a terceirização e a relocalização de fábricas para o nordeste brasileiro. Os distritos italianos estão cada vez mais ligados às CGVs, enquanto os brasileiros se ligam às cadeias nacionais, e só marginalmente se conectam às CGVs em redes de governança. Assim, os DIs/clusters não perderam relevância na globalização, antes eles buscaram novas maneiras de produzir, flexibilizando, respondendo ao mercado consumidor, buscando qualidade, via tecnologia, diferenciando os produtos, utilizando a terceirização, negociando com fornecedores, fabricando lotes menores. Nesse contexto os DIs/clusters analisados sobreviveram e estão atuantes no mercado.
Do Political or Security Conditions Determine When American Security Transfers Are Made?
Authors: Cooley Jason
Published: June 2020

When terrorist attacks became more frequent and destructive in the early portion of the twenty-first century, American officials asserted that Islamist networks needed to be crippled. After a campaign against these groups was launched, Washington began to rely on some new security measures. For the past two decades, several studies have been produced about innovations such as drone strikes. What has not been seen, though, are analyses of measures that the U.S. unveiled in the Cold War and has continued to use in the effort against Islamist organizations. Within this article, America;s continued reliance on transferal operations will be taken into consideration. While a military intervention is in progress, policymakers declare that U.S. troops will be withdrawn from a country once indigenous elements are capable of inheriting their responsibilities. However, a security transfer usually takes place when the intervention becomes unpopular on the American home front.
Net ozone production and its relationship to nitrogen oxides and volatile organic compounds in the marine boundary layer around the Arabian Peninsula
Authors: Tadic Ivan , Crowley John N. , Dienhart Dirk , Eger Philipp , Harder Hartwig , Hottmann Bettina , Martinez Monica , Parchatka Uwe , Paris Jean-Daniel , Pozzer Andrea , Rohloff Roland , Schuladen Jan , Shenolikar Justin , Tauer Sebastian , Lelieveld Jos , Fischer Horst
Published: June 2020

Abstract. Strongly enhanced tropospheric ozone (O3) mixing ratios have
been reported in the Arabian Basin, a region with intense solar radiation
and high concentrations of O3 precursors such as nitrogen oxides (NOx) and
volatile organic compounds (VOCs). To analyze photochemical O3 production in the
marine boundary layer (MBL) around the Arabian Peninsula, we use shipborne
observations of NO, NO2, O3, OH, HO2, HCHO, the actinic flux,
water vapor, pressure and temperature obtained during the summer 2017 Air
Quality and Climate in the Arabian Basin (AQABA) campaign, and we compare them to
simulation results from the ECHAM-MESSy Atmospheric Chemistry (EMAC) general
circulation model. Net O3 production rates (NOPRs) were greatest over both the Gulf of Oman and the northern Red Sea (16 ppbv d−1) and
over the Arabian Gulf (32 ppbv d−1). The NOPR over the
Mediterranean, the southern Red Sea and the Arabian Sea did not
significantly deviate from zero; however, the results for the Arabian Sea
indicated weak net O3 production of 5 ppbv d−1 as well as net O3
destruction over the Mediterranean and the southern Red Sea with values of −1 and −4 ppbv d−1, respectively. Constrained
by HCHO∕NO2 ratios, our photochemistry calculations show that net O3
production in the MBL around the Arabian Peninsula mostly occurs in
NOx-limited regimes with a significant share of O3 production
occurring in the transition regime between NOx limitation and VOC limitation over
the Mediterranean and more significantly over the northern Red Sea and Oman
Gulf.
Aqueous particle generation with a 3D printed nebulizer
Authors: Rösch Michael , Cziczo Daniel J.
Published: June 2020

Abstract. In this study, we describe the design and testing of a high output stability constant liquid feed nebulizer using the Venturi principle to generate liquid particles from solutions. This atomizer, the PRinted drOpleT Generator (PROTeGE) was manufactured using stereolithography (SLA) printing. Different concentrations of ammonium sulfate solutions were used to characterize the size and number concentration of the generated particles. A comparison of a 3D printed 0.5 mm orifice with a more dimensionally accurate and symmetric machined 0.5 mm brass orifice using the same ammonium sulfate solutions was also performed. PROTeGE is also shown to be capable of dispersing polystyrene latex spheres (PSLs) for calibration purposes. The particle number concentrations obtained in this study ranged from ~10 000 cm−3 for 0.75 micrometer to ~100 cm−3 for 5.0 micrometer PSL particles with a dependence on the concentration of the dispersed solution. PROTeGE is easy to manufacture and operate, low in maintenance, and cost-effective for laboratory and field generation of particles from aqueous media.
Competencies based innovative learning solutions for co-development of climate services in West Africa
Authors: Tarchiani Vieri , Rapisardi Elena , Parrish Patrick , Di Giuseppe Edmondo , Bacci Maurizio , Baldi Marina , Pasqui Massimiliano
Published: June 2020

Abstract. In developing countries, and particularly in West Africa, the role of Climate Services (CS) for sustainable development is growing thanks to wide spreading collaboration among European institutions, including National Meteorological and Hydrological Services (NMHS) research centers, universities, and homologue local institutions. Operationally, the
implementation of CSs in developing countries is mainly pivoted on NMHS,
which, according to the World Meteorological Organization (WMO), are
dramatically affected by unmet learning demand. The global scale of learning needs for co-development of CSs calls for
innovative solutions and a range of flexible modalities to reach learners in
a variety of ways, and for sharing resources and successful strategies
within the global education and training community. In order to harmonize
expected learning outcomes, WMO defined a competency framework (CF) for CSs
to be used in the implementation of training initiatives and knowledge
sharing tools. This paper presents the strategic and methodological approach adopted in the
implementation of the TOPaCS, a new knowledge-based distance learning
initiative, aiming to provide a flexible learning environment within the CSs CF of WMO ensuring coherence with other WMO education initiatives (Global Campus, other RTCs, etc.). The methodological approach adopted is based on the competency-based approach to training, where competencies are composed by elements of
knowledge and skill. TOPaCS integrates the WMO CF for CSs into a taxonomy
co-designed with stakeholders at different levels, and allows the definition
of learning paths, which are a further interactive opportunity for
co-development of CSs within the TOPaCS learning ecosystem. Indeed, the
approach aims also to guide further instructional strategies and assessments
and becomes a starting point to build a common language enabling a better
cooperation and exchange between the different CSs training initiatives.
Deepening roots can enhance carbonate weathering
Authors: Wen Hang , Sullivan Pamela L. , Macpherson Gwendolyn L. , Billings Sharon A. , Li Li
Published: June 2020

Abstract. Carbonate weathering is essential in regulating atmospheric CO2 and carbon cycle at the century time scale. Plant roots have been known to accelerate weathering by elevating soil CO2 via respiration. It however remains poorly understood how and how much rooting characteristics (e.g., depth and density distribution) modify flow paths and weathering. We address this knowledge gap using field data from and reactive transport numerical experiments at the Konza Prairie Biological Station (Konza), Kansas (USA), a site where woody encroachment into grasslands is surmised to deepen roots. Results indicate that deepening roots potentially enhance weathering in two ways. First, deepening roots can control thermodynamic limits of carbonate dissolution by regulating how much CO2 transports downward to the deeper carbonate-rich zone. The base-case data and model from Konza reveal that concentrations of Ca and Dissolved Inorganic Carbon (DIC) are regulated by soil pCO2 driven by the seasonal fluctuation of soil respiration. This relationship can be encapsulated in equations derived in this work describing the dependence of Ca and DIC on temperature and soil CO2, which has been shown to apply in multiple carbonate-dominated catchments. Second, numerical experiments show that roots control weathering rates by regulating the amount of water fluxes that flush through the carbonate zone and export reaction products at dissolution equilibrium. Numerical experiments explored the potential effects of partitioning 40 % of infiltrated water to depth in woodlands compared to 5 % in grasslands. Soil CO2 data from wood- and grasslands suggest relatively similar soil CO2 distribution over depth, and only led to 1 % to 12 % difference in weathering rates if flow partitioning was kept the same between the two land covers. In contrast, deepening roots can enhance weathering by 17 % to 207 % as infiltration rates increased from 3.7 × 10−2 to 3.7 m/yr. Numerical experiments also indicated that weathering fronts in woodlands propagated > 2 times deeper compared to grasslands after 300 years at the infiltration rate of 0.37 m/yr. These differences in weathering fronts are ultimately caused by the contact time of CO2-charged water with carbonate rocks. We recognize that modeling results are subject to limitations in representing processes and parameters, but we propose that the data and numerical experiments allude to the hypothesis that (1) deepening roots can enhance carbonate weathering; (2) the hydrological impacts of rooting characteristics can be more influential than those of soil CO2 distribution in modulating weathering rates. We call for co-located characterizations of roots, subsurface structure, soil CO2 levels, and their linkage to water and water chemistry. These measurements will be essential to improve models and illuminate feedback mechanisms of land cover changes, chemical weathering, global carbon cycle, and climate.
Synthetic Weather Diaries: Concept and Application to Swiss Weather in 1816
Authors: Brönnimann Stefan
Published: June 2020

Abstract. Climate science is about to produce numerical daily weather reconstructions based on meteorological measurements for Central Europe 250 years back. Using a pilot reconstruction covering Switzerland at 2 × 2 km2 resolution for 1816, this paper presents methods to translate numerical reconstructions and derived indices into text describing daily weather and the state of vegetation. This facilitates comparison with historical sources and analyses of effects of weather on different aspects of life. The translation, termed synthetic weather diary could possibly be used to train machine learning approaches to do the reverse: reconstruct past weather from categorized text entries in diaries.
Quality assurance and control on hydrological data off western Sardinia (2000–2004), western Mediterranean
Authors: Ribotti Alberto , Sorgente Roberto , Borghini Mireno
Published: June 2020

Abstract. Seven oceanographic cruises in 5 years were organized
in the Sea of Sardinia with the repeated collection of physical, chemical and
biological data. An accurate and sustained quality assurance on physical
sensors was enacted through pre- and postcruise calibration and verified
during in situ acquisitions with the use of redundant sensors and other
instruments. Moreover, for dissolved oxygen and conductivity, seawater
samples at standard depths were frequently analyzed on board. Then an
accurate quality control was used to verify all hydrological data profiles,
which passed a further quality check following standard procedures. Finally
all hydrological data have been included in two online public open-access
datasets in the SEANOE (SEA scieNtific Open data Edition) repository (https://doi.org/10.17882/59867 and
https://doi.org/10.17882/70340; Ribotti et al., 2019a, b). During and after
all cruises Chlorophyll a and nutrient analyses were also carried out, but these
data are not yet open access; the same applies for water current profiles, both at
casts and during vessel moves, and geophysical data. These ocean data are
the first covering the Sea of Sardinia for its whole extension. Here data
and assurance and control procedures used are described as they have become standards
in deep-sea acquisitions over the years.
The impact of landscape evolution on soil physics: Evolution of soil physical and hydraulic properties along two chronosequences of proglacial moraines
Authors: Hartmann Anne , Weiler Markus , Blume Theresa
Published: June 2020

Abstract. Soil physical properties highly influence soil hydraulic properties which define the soil hydraulic behavior. Thus, changes within these properties affect water flow paths and the soil water and matter balance. Most often these soil physical properties are assumed to be constant in time and little is known about their natural evolution. Therefore, we studied the evolution of physical and hydraulic soil properties along two soil chronosequences in proglacial forefields in the Central Alps, Switzerland. One soil chronosequence developed on silicate and the other on calcareous parent material. Each soil chronosequence consisted of 4 moraines with the ages of 30, 160, 3000, and 10 000 years at the silicate forefield and 110, 160, 4900, and 13 500 years at the calcareous forefield. We investigated bulk density, porosity, the content of clay, silt, sand, and gravel as well as loss on ignition and hydraulic properties in form of retention curves and hydraulic conductivity curves. Samples were taken in three depths (10, 30, 50 cm) at six sampling sites at each moraine. Soil physical and hydraulic properties change considerably over the chronosequence. Particle size distribution shows a pronounced reduction in sand content and an increase in silt and clay content over time at both sites. Bulk density decreases and porosity increases during the first 10 millenia of soil development. The trend is equally present at both parent materials, but the reduction in sand and increase in silt content was more pronounced at the calcareous site. The organic matter content increases, which is especially pronounced in the top soil at the silicate site. With the change in physical soil properties and organic matter content the hydraulic soil properties change from fast draining coarse textured soils to slow draining soils with high water holding capacity, which is also more pronounced in the top soil at the silicate site. The dataset presented in this paper is available at the online repository of the German Research Center for Geosciences (GFZ, Hartmann et al. (2020b)). The dataset can be accessed via the link: http://pmd.gfz-potsdam.de/panmetaworks/review/f46bd4d822a0766a9c0baf356bc7e55644d65d62d7ab71527f5d80c35eed11e5 and will be published with the DOI specified under the link.
Evaluating and improving the treatment of gases in radiation schemes: the Correlated K-Distribution Model Intercomparison Project (CKDMIP)
Authors: Hogan Robin J. , Matricardi Marco
Published: June 2020

Abstract. Most radiation schemes in weather and climate models use the 'correlated k-distribution' (CKD) method to treat gas absorption, which approximates a broadband spectral integration by N pseudo-monochromatic calculations. Larger N means more accuracy and a wider range of gas concentrations can be simulated, but at greater computational cost. Unfortunately, the tools to perform this efficiency-accuracy trade-off (e.g., to generate separate CKD models for applications such as short-range weather forecasting to climate modelling) are unavailable to the vast majority of users of radiation schemes. This paper describes the experimental protocol for the Correlated K-Distribution Model Intercomparison Project (CKDMIP), whose purpose is to use benchmark line-by-line calculations: (1) to evaluate the accuracy of existing CKD models, (2) to explore how accuracy varies with N for CKD models submitted by CKDMIP participants, (3) to understand how different choices in way that CKD models are generated affects their accuracy for the same N, and (4) to generate freely available datasets and software facilitating the development of new gas-optics tools. The datasets consist of the high-resolution longwave and shortwave absorption spectra of nine gases for a range of atmospheric conditions, realistic and idealized. Thirty-four concentration scenarios for the well-mixed greenhouse gases are proposed to test CKD models from palaeo- to future-climate conditions. We demonstrate the strengths of the protocol in this paper by using it to evaluate the widely-used Rapid Radiative Transfer Model for General Circulation Models (RRTMG).
DeerLab: A comprehensive toolbox for analyzing dipolar EPR spectroscopy data
Authors: Fábregas Ibáñez Luis , Jeschke Gunnar , Stoll Stefan
Published: June 2020

Abstract. Dipolar EPR spectroscopy (DEER and other techniques) enables the structural characterization of macromolecular and biological systems by measurement of distance distributions between unpaired electrons on a nanometer scale. The inference of these distributions from the measured signals is challenging due to the ill-posed nature of the inverse problem. Existing analysis tools are scattered over several applications with specialized graphical user interfaces. This renders comparison, reproducibility, and method development difficult. To remedy this situation, we present DeerLab, an open-source MATLAB toolbox for analyzing dipolar EPR data that is modular and implements a wide range of methods. We show that DeerLab can perform one-step analysis based on separable non-linear least squares, fit dipolar multi-pathway models to multi-pulse DEER data, and run global analysis with parameter-free distributions. Important aspects of uncertainty analysis are discussed as well.
Nicanor Parra, el taoísmo y el modernismo
Authors: Serna Arnaiz Mercedes
Published: June 2020

Con “Nicanor Parra, el taoísmo y el modernismo”, pretendo analizar la relación que guarda el modernismo con el taoísmo, pensamiento filosófico basado en la integración de los contrarios. Parto de una introducción en la que advierto cómo ya desde la propia escuela modernista y hasta las segundas vanguardias, algunos poetas ironizaron sobre ciertos temas, tópicos o visiones propiamente modernistas (la belleza de la mujer, el erotismo como salvación, la sacralización del arte, la voluntad de estilo o el simbolismo o alquimia verbal) hasta llegar a su máxima expresión con la antipoesía. El tono misógino, una visión “desublimada” del amor, la alienación del yo como elementos que parodian la identidad, elementos todos ellos que caracterizan la poesía parriana, deben interpretarse como una ruptura de los conceptos y tópicos modernistas y un intento de deconstruir toda una literatura romántica y platónica para lograr el equilibrio taoísta de la naturaleza.
Ἑλληνισμός em 2 Macabeus
Authors: Ruppenthal Neto Willibaldo
Published: June 2020

O presente artigo visa analisar o significado de Ἑλληνισμός em 2 Macabeus, percebendo tal uso dentro de um contexto de ressignificação do termo no período helenístico. Para isto, se analisa o sentido original de Ἑλληνισμός em relação ao verbo Ἑλληνίζω e sua transformação ao longo do tempo, especialmente no contexto helenístico. Também, se busca analisar o sentido que os termos relacionados a Βαρβαρισμός e Ἕλληνες têm em 2 Macabeus e sua importância no estabelecimento de um novo sentido para Ἑλληνισμός neste livro.
Música, discursos e poder: reflexões sobre a hierarquização do conhecimento
Authors: Ferreira Alexandre
Published: June 2020

Este artigo apresenta uma reflexão crítica sobre a relação entre os discursos de legitimação, que sustentam os géneros musicais, e a hierarquização do conhecimento como forma de dominação no campo da ciência. O texto centra-se na polarização música “erudita” e música “popular”, discorrendo sobre os efeitos da mesma na formação dos músicos contemporâneos nas instituições de ensino. Usamos a Música para Cinema como exemplo concreto das ambiguidades e fragilidades discursivas que têm colocado a música “erudita” no centro da investigação e prática académica. Finalmente, sugere-se a inclusão das perspetivas teóricas e metodológicas dos Estudos Culturais como resposta à resistência da Musicologia tradicional, que tem subalternizado as práticas musicais populares em geral e os géneros contemporâneos em particular. Advoga-se um reposicionamento académico no que respeita à formação dos músicos e à Música, que possa resultar na democratização e inclusão das práticas musicais contemporâneas.
DESEMPENHO TÉRMICO DE UMA RESIDÊNCIA COM DIFERENTES CONFIGURAÇÕES DE PAREDES TROMBE: ESTUDO PARA CURITIBA - PR
Authors: Ziebell Clarissa Sartori , Aymone José Luís Farinatti
Published: June 2020

RESUMO:  O uso de tecnologias passivas para climatizar os ambientes, tal como a parede Trombe, é uma forma reconhecida para minimizar o gasto energético com a climatização artificial do ar. Este artigo tem como objetivo avaliar, através do software EnergyPlus, a influência de diferentes paredes Trombe em uma edificação residencial, considerando o contexto climático de Curitiba, cidade que apresenta baixas temperaturas médias mensais. Para uma análise mais completa a respeito das vantagens em utilizar uma parede Trombe, foi realizado ainda um levantamento de custo do sistema. A partir das análises realizadas, constatou-se que o uso de paredes Trombe permitiu a elevação das temperaturas internas, especialmente quando foram abertas as janelas de ventilação interna. Contudo, nos dias de temperaturas externas muito baixas o uso da parede Trombe não foi suficiente para garantir o conforto térmico dos ocupantes. Durante o verão, a parede Trombe não provocou desconforto térmico por calor. Apesar de ter sua eficiência comprovada, verificou-se que o preço da esquadria pode ser um impedimento para a adoção do sistema. Sendo assim, ressalta-se a importância de um estudo a respeito do desempenho da parede Trombe combinado com outras estratégias bioclimáticas. Do contrário, o uso de climatização artificial será necessário.
 ABSTRACT: The use of passive technologies to climatize the environment, as the Trombe wall, is a recognized way to minimize energy waste with artificial air conditioning This paper aims to evaluate, through use of the software EnergyPlus, the influence of different Trombe walls on a residential building, considering the climate context of Curitiba, city where the monthly mean temperatures are low. For a more complete analysis of the advantages in using a Trombe wall, the cost of the system was also verified. From the analyzes carried out, the use of Trombe walls was found to be an alternative to allow the increase of internal temperatures, especially when the internal ventilation windows where opened. However, on days of very low external temperatures the use of the Trombe wall was not enough to guarantee the thermal comfort of the occupants. During the summer, the Trombe wall did not cause thermal discomfort by heat. Despite its proven efficiency, the window price was found to be an impediment for the system adoption. Thus, is emphasized the importance of a study on the performance of the Trombe wall combined with other bioclimatic strategies. Otherwise, the use of artificial air conditioning will be necessary.
EFEITO DA ADIÇÃO DE FIBRAS DE AÇO E POLIMÉRICAS NA RESISTÊNCIA À COMPRESSÃO DO CONCRETO DE ULTRA ALTO DESEMPENHO
Authors: Balestra Carlos Eduardo Tino , Ozelame Jennifer Stephane , Savaris Gustavo
Published: June 2020

RESUMO: A exigência de materiais com desempenho superior aos utilizados usualmente na construção civil impulsiona pesquisas que visam o desenvolvimento de novas tecnologias. Neste contexto, surgem os concretos de ultra alto desempenho reforçados com fibras (UHPFRC), que se destacam pelas elevadas resistências à compressão e à tração e maior ductilidade em relação a um concreto convencional. O presente trabalho teve como objetivo principal avaliar experimentalmente a resistência à compressão e comportamento pós ruptura de UHPFRC com diferentes tipos e dosagens de fibras, utilizando materiais disponíveis no mercado brasileiro, visando o emprego deste material nos processos construtivos atuais. A partir de um traço de concreto de ultra alto desempenho foram definidas misturas de UHPFRC com fibras de aço e de fibras de polietileno utilizando volumes de 0,5% e 1% de fibras. Os resultados obtidos foram comparados a um concreto de referência sem fibras, demonstrando que as fibras melhoram a ductilidade do concreto e provém uma resistência residual ao mesmo, sendo observados, após sua fratura, picos de recuperação graças à melhor aderência das fibras ao concreto. Além disso, para ambas as fibras, uma maior quantidade de fibras auxiliou a combater as rupturas bruscas observadas após concretos sem fibras esgotarem sua capacidade resistente.

ABSTRACT: The demand for materials with higher performance than those usually used in civil construction stimulate researches aimed at the development of new technologies. In this context, ultra high performance fibers reinforced concrete (UHPFRC) stands out due to the high compressive and tensile strengths and higher ductility compared to conventional concrete. The present work had as main objective to evaluate experimentally the compressive strength and post - rupture behavior of UHPFRC with different types and dosages of fibers, using materials available in Brazil, aiming the use of these material in the current constructive processes. UHPFRC mixtures with steel fibers and polyethylene fibers using 0.5% and 1% fiber volumes were defined from an ultra high performance concrete mixture. The results obtained were compared to a reference concrete without fibers, demonstrating that the fibers improve the ductility of the concrete and provide a residual resistance after the exemplar fracture, recovery peaks due to the better adhesion of the fibers to the concrete. In addition, for both fibers, a greater amount of fibers helped to avoid sudden ruptures observed after concrete without fibers reached their resistant capacity.
ANÁLISE 2D E 3D DA ESTABILIDADE DA BARRAGEM DE FUNDÃO
Authors: Gitirana Jr. Gilson de Farias Neves , Souza João Paulo Tavares , Moura Nícolas Rodrigues
Published: June 2020

RESUMO: A falha da Barragem de Fundão, o maior desastre de seu tipo no mundo, foi estudada por Morgenstern et al. (2016) através de abordagens bidimensionais. A investigação realizada não apontou mecanismos de instabilidade de taludes como sendo as causas do desastre. No entanto, o formato complexo da face da barragem, com regiões côncavas e convexas, não foi considerado devido às limitações das ferramentas empregadas. Este trabalho apresenta análises bidimensionais (2D) e tridimensionais (3D), teoricamente mais rigorosas e adequadas para a geometria da barragem. As análises de estabilidade do maciço foram realizadas utilizando o Método Geral das Fatias e das Colunas (GLE), por meio do software SVSLOPE. Foram realizadas buscas por superfícies críticas 2D e 3D, ao longo de todas as zonas da estrutura. Considerando-se parâmetros de resistência drenada, observou-se que Fundão se encontraria em condições de elevada segurança, sendo o menor Fator de Segurança igual a 1,744. Valores próximos de 1,0 foram obtidos considerando rejeitos na condição não drenada, supostamente menos representativa das condições reais de campo. Os Fatores de Segurança 3D se mostraram muito próximos dos 2D, porém com variações significativas nas regiões côncava e convexa. Desta forma, conclui-se que o formato próximo à região do recuo exige maior atenção e análises 3D podem identificar as regiões críticas.
ABSTRACT: The failure of the Fundão Dam, the largest disaster of its kind in the world, was studied by Morgenstern et al. (2016) using two-dimensional approaches. The carried out investigation did not point to mechanisms of slope instability as the causes of the disaster. However, the complex shape of the dam and its concave and convex regions were not originally considered due to limitations of the analysis tools employed. This paper presents two-dimensional (2D) and three-dimensional (3D) analyses that are more rigorous and well suited for the Fundão dam geometry. Slope stability analyses were accomplished using the General Limit Equilibrium Method of Slices and Columns (GLE) using the SVSLOPE software. Critical slip surfaces were searched in 2D and 3D, across the entire dam face. Drained shear strength parameters led to Factors of Safety that would indicate fairly stable conditions, with a lowest Factor of Safety of 1.744. Values close to 1.0 were obtained considering undrained conditions of the tailings, which are supposedly less representative of field conditions. The 3D factors of safety were very close to the 2D values, but with noticeably higher variations near the concave and convex regions. This leads to the conclusion that the dam shape near the setback region requires closer examination by means of 3D analyses that enable the identification of critical zones.