bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Optimisation of a Helicopter Engine Inlet Electrothermal Ice Protection System
Authors: Moser Richard , Roberts Ian
Published: June 2019

This paper details the process involved in the numerical optimisation of a helicopter engine inlet electrothermal ice protection system. Although the process was developed using a production aircraft, it is demonstrated here using a generic intake and flight conditions, due to confidentiality of the actual design. The process includes adherence to the overall system design objectives (maximum power demand), including tolerances required to account for an industrial system (aircraft voltage variation, manufacturing tolerances). The numerical optimisation was performed using a combination of 2D and 3D methods to define the required heated area, power density, locations and settings for temperature control sensors. The use of 2D design tools allows a rapid iteration process to be performed, leading to the possibility of a higher level of optimisation within the allowable time-frame compared to the use of full 3D methods. Different flight settings (different Angle of Attack and Angle of Sideslip) were analysed, for two different droplet diameters (MVD values of 20 microns and 40 microns, coherent with the requirements of the CS-29 Appendix C icing envelope). An iterative transient thermal analysis was then performed, over the required temperature range of 0°C to -30°C, to optimise the heater placement and heater powers, assessing the predicted level of ice accretion in all cases. Assessment in dry conditions in the range of +5°C to -30°C was also performed in order to ensure that structural over-temperature did not occur. The positions of embedded temperature sensors were defined as part of the analysis, including the temperature control values which would feed into the controller. The process was deemed to be successful as the final design was successfully tested in flight and in an icing wind tunnel facility.
Study on Microstructural Characteristics and Mechanical Behaviour of AISI1050 Steel under Various Heat Treatments
Authors: Sundar Singh Sivam S.P. , Loganathan Ganesh Babu , Umasekar V.G. , Saravanan K. , Suresh Kumar P.S. , Raja Saravanan
Published: June 2019

Heat treatment of metal alloys is one of the most widely used techniques for achieving the desired mechanical properties by modifying the microstructure namely the grain and or by altering the second phases present in heat treat able alloys. At times heat treated materials undergo further process like forming, machining, welding etc. Thus the present work describes the effect of heat treatment of AISI 1050 steel and its associated micro structural changes that correlate it with the mechanical behaviour. AISI 1050 steel is widely used in the production of bearings, landing gear, actuators and aerospace structural components. In this study, different samples of AISI 1050 steel were heat treated to temperature above the austenitic region and were subjected to annealing or normalising, or spheroiding. It is indicative that the properties of the AISI 1050 steel can be easily altered by heat treatment to suit a particular application and for secondary processing. The property comparison includes micro structural grain size, yield strength, tensile strength, hardness and percentage elongation. Thus the results provide a better insight on the process of increasing the versatility of the AISI 1050 steel for its demanding use in aerospace structural applications and related mechanical processing. It was found that the effect of heat treatment has resulted in increased grain size, decreased strength and hardness, and improved properties which were more suitable for machining and forming process.
Experimental Investigation of Alumina Reinforced Copper Metal Matrix Composite by Stir Casting Method
Authors: Palanivendhan M. , Chandradass J. , Rajendran Ajith , Govindarajan Nishanth M. , Adwait Krishnaa M.
Published: June 2019

In the present study, alumina reinforced copper metal matrix composites were prepared by stir casting method. Three different specimens were prepared by changing the weight ratio of alumina to copper. The samples were prepared by adding 10%, 20% and 30% alumina to copper matrix. The three specimens were subjected to mechanical, thermal and corrosion testing, in order to find out the properties of the material. Various mechanical tests like hardness, impact and corrosion were performed including thermal conductivity to understand the behaviour of the specimens under combined loads. Specimen number 2 which was 80%-20% copper to alumina was found to be the best combination for such type of applications.
Fatores motivacionais e modificações na vida dos mestrandos em contabilidade: os dois lados de uma mesma história
Authors: Meurer Alison Martins , Souza Antônio Nadson Mascarenhas , Costa Flaviano
Published: June 2019

O ingresso no mestrado ocasiona modificações relevantes na vida dos alunos, seja nos âmbitos social, financeiro ou psicológico. As alterações da realidade frente aos novos compromissos podem gerar algumas consequências para os estudantes, e comprometer seu desempenho no curso. Nesse sentido, esta investigação buscou identificar as modificações (sociais, financeiras e psicológicas) ocorridas na vida dos alunos do mestrado em contabilidade após o ingresso no programa de pós-graduação. Sob a lente teórica das teorias do Capital Humano e da Autodeterminação foram identificadas as motivações que fomentaram o anseio e a tomada de decisão dos participantes para ingressarem no mestrado em contabilidade. Para a coleta das evidências foram realizadas entrevistas semiestruturadas e aplicado questionário em 12 mestrandos de uma instituição de ensino superior pública brasileira. O roteiro de entrevista foi submetido as validações propostas pela literatura especializada, sendo que os aspectos éticos foram observados pelos pesquisadores. A partir da análise dos discursos dos participantes foi possível identificar alguns achados relevantes e que devem ser considerados pelas coordenações dos cursos de pós-graduação brasileiros, pelos órgãos de fomento, professores, alunos e futuros candidatos. Primeiramente, os resultados apontam que em todos os aspectos elencados, financeiros e sociais, houveram modificações na vida da maioria dos participantes. As falas indicam que o fator financeiro é considerado um dos mais importantes e observado pelos mestrandos com vistas a conclusão do curso. Ademais, a sobrecarga de atividades e a falta de planejamento tanto em relação ao tempo como aos aspectos financeiros impactam psicologicamente os alunos. Percebeu-se também, que as motivações que levaram os estudantes a ingressarem no programa de pós-graduação alinham-se aos objetivos profissionais, mas estão também, fortemente relacionadas a satisfação pessoal e demais motivações intrínsecas. Destarte, considera-se que o estudo tenha dado voz aos mestrandos, na medida que inova por seu caráter qualitativo e análise em profundidade. Por fim, essa investigação é reflexo do retrato e desenho da pós-graduação existente no Brasil. Espera-se que os achados sirvam de embasamento para que as políticas de manutenção estudantil sejam mantidas e aprimoradas, bem como o próprio desenho da pós-graduação brasileira.
Análise da relação entre rentabilidade e estratégias de gestão do capital de giro das empresas listadas na B3
Authors: Rech Ilírio José , Cunha Moisés Ferreira , Rabelo Carolina Teixeira , Barbosa Alessandra
Published: June 2019

O objetivo principal da administração do capital de giro é manter equilíbrio entre cada um de seus componentes e, com isso, o equilíbrio entre o risco de insolvência e a rentabilidade. A empresa pode, portanto, adotar uma política agressiva ou conservadora de administração do capital de giro, dependendo da estratégia da gestão. Nesse sentido, o objetivo deste artigo é analisar a influência das estratégias de gestão do capital de giro na rentabilidade das empresas listadas na B3. Foi, então, selecionada uma amostra de 152 empresas listadas na B3 e segregadas entre política agressiva ou conservadora de gestão do capital de giro. O período analisado foi de 2000 a 2014 e os dados coletados consistem de ativo circulante, passivo circulante, ativo total, rentabilidade do ativo total e rentabilidade do patrimônio líquido. Os dados foram organizados e analisados com base na regressão simples e multivariada. Os resultados indicam que a estratégia de investimento em capital de giro influencia positivamente a rentabilidade do ativo total e do patrimônio líquido. No que diz respeito à política de financiamento, verificou-se que as empresas, quando analisadas em conjunto, apresentaram influência negativa da agressividade de financiamento na rentabilidade do ativo e do patrimônio líquido. No entanto, as empresas que adotam agressividade na política de financiamento acima da média e apresentam rentabilidade sobre o ativo acima da média representam influência positiva da política de financiamento na rentabilidade.
Trabalho, tempo livre e aposentadoria: categorias coexistentes dentro do processo de envelhecimento
Authors: Gurgel Lorena Ibiapina , Pinheiro Adriana de Alencar Gomes , Queiroz Kalyana Cristina Fernandes , Babosa Júnior Francisco Welligton Sousa , Martins José Clerton Oliveira
Published: June 2019

Trabalho e aposentadoria são temas recorrentes no cenário das pesquisas no Brasil, notadamente devido à elevação da expectativa de vida, que possibilitou aos indivíduos um tempo logo após a aposentadoria que necessita ser visto, compreendido e explorado. Este artigo objetiva discutir sobre três categorias que envolvem o idoso no séc. XXI - Trabalho, Tempo Livre e Aposentadoria – mediante desenvolvimento de pesquisa de natureza bibliográfica em livros e artigos correlatos ao assunto. Obteve-se que o trabalho pode ser compreendido de forma positiva e negativa e que a maneira como o idoso vive reflete em uma aposentadoria com significados agradáveis ou desagradáveis - tempo livre que alguns até desejam, enquanto outros temem, pelo sentimento de inutilidade e abandono que suscita. Conclui-se que o estar aposentado no séc. XXI envolve uma gama de interpretações e o simbolismo individual desse tempo de forma peculiar, influenciado pela sua história de vida.
Um estudo da mulher no processo educativo medieval do século IX: reflexões sobre o Manual de Dhuoda
Authors: Oliveira Terezinha , Viana Ana Paula dos Santos
Published: June 2019

O objetivo desse artigo é refletir sobre o lugar da mulher no processo educativo medieval do século IX. Este estudo pauta-se no âmbito da história da educação e será feito segundo reflexões do Manual La educación cristiana de mi hijo, de Dhuoda (c. 800-843). A autora foi uma mãe nobre, de origem germânica, que viveu no período da dinastia carolíngia. A proposta é evidenciar, com o escrito dessa mulher ‘educadora’, o lugar do feminino na educação medieval do século IX. Ao prezar pela formação humana e intelectual de seu filho, Dhuoda redige o Manual fundamentando-se nos escritos clássicos de sua época. Nesse sentido, o propósito é evidenciar que neste período havia uma preocupação com a educação da criança e, no caso da nobreza, essa ‘função’ era feminina.
Protocolos de avaliação de risco: ferramentas para avaliar e combater a violência contra as mulheres
Authors: Strey Marlene Neves , Jardim Renata Teixeira
Published: June 2019

A violência de gênero, principalmente a cometida contra as mulheres é um fenômeno mundial e está historicamente ancorada em práticas sexistas amplamente disseminadas, sendo considerada como todo ato de violência baseada no gênero que tenha ou possa ter como resultado um dano e sofrimento para as mulheres. Neste texto é apresentado o modelo integral de fases de liberação e recuperação dessas mulheres de Neus Roca Cortés e colaboradoras. Trata-se de um modelo com perspectiva de gênero buscando a compreensão da dinâmica psicossocial da mulher durante o tempo que transcorre entre a vinculação com o companheiro que exercerá a violência, até a liberação dessa violência e a reconstrução da própria vida em liberdade. São tecidas considerações sobre a necessidade de criação de instrumentos para detectar a gravidade dos riscos que as mulheres podem sofrer, como prevenção e proteção das mesmas em seu processo de busca de ajuda.
Climate impact of Finnish air pollutants and greenhouse gases using multiple emission metrics
Authors: Kupiainen Kaarle Juhana , Aamaas Borgar , Savolahti Mikko , Karvosenoja Niko , Paunu Ville-Veikko
Published: June 2019

Abstract. We present a case study where emission metric values from
different studies are applied to estimate global and Arctic temperature
impacts of emissions from a northern European country. This study assesses
the climate impact of Finnish air pollutants and greenhouse gas emissions
from 2000 to 2010, as well as future emissions until 2030. We consider both emission
pulses and emission scenarios. The pollutants included are SO2, NOx, NH3,
non-methane volatile organic compound (NMVOC), black carbon (BC), organic carbon (OC), CO, CO2, CH4 and N2O, and our study is the first
one for Finland to include all of them in one coherent dataset. These
pollutants have different atmospheric lifetimes and influence the climate
differently; hence, we look at different climate metrics and time horizons.
The study uses the global warming potential (GWP and GWP*), the global
temperature change potential (GTP) and the regional temperature change
potential (RTP) with different timescales for estimating the climate
impacts by species and sectors globally and in the Arctic. We compare the
climate impacts of emissions occurring in winter and summer. This assessment
is an example of how the climate impact of emissions from small countries
and sources can be estimated, as it is challenging to use climate models to
study the climate effect of national policies in a multi-pollutant
situation. Our methods are applicable to other countries and regions and
present a practical tool to analyze the climate impacts in multiple
dimensions, such as assessing different sectors and mitigation measures.
While our study focuses on short-lived climate forcers, we found that the CO2
emissions have the most significant climate impact, and the significance
increases over longer time horizons. In the short term, emissions of
especially CH4 and BC played an important role as well. The warming impact
of BC emissions is enhanced during winter. Many metric choices are
available, but our findings hold for most choices.
Variability and long-term changes of brominated VSLS at the tropical tropopause
Authors: Tegtmeier Susann , Atlas Elliot , Quack Birgit , Ziska Franziska , Krüger Kirstin
Published: June 2019

Abstract. We combine available observational data sets with Lagrangian atmospheric modelling in order to analyze the spatial and temporal variability of the CHBr3 injection into the stratosphere. Regional maxima with mixing ratios of up to 0.4–0.5 ppt at 17 km altitude are diagnosed to be over Central America (1) and over the Maritime Continent/West Pacific (2), both of which are confirmed by high-altitude aircraft campaigns. The CHBr3 maximum over Central America is caused by the co-occurrence of convectively-driven short transport time scales and strong regional sources, which in conjunction drive the seasonality of CHBr3 injection. Model results at a daily resolution reveal isolated, exceptionally high CHBr3 values in this region which are confirmed by measurements during the ACCENT campaign and do not occur in spatially or temporally averaged model fields. CHBr3 injection over the West Pacific is centered south of the equator due to strong oceanic sources underneath prescribed by the here applied bottom-up emission inventory. The globally strongest stratospheric CHBr3 injection of up to 0.6 ppt is diagnosed to occur over the region of India, Bay of Bengal and Arabian Sea (3), however, no data from aircraft campaigns are available to confirm this finding. Interannual variability of stratospheric CHBr3 injection of 10–20 % is to a large part driven by the variability of coupled ocean-atmosphere circulation systems. Long-term changes, on the other hand, correlate with the regional SST trends resulting in positive trends of stratospheric CHBr3 injection over the West Pacific and Asian monsoon region and negative trends over the East Pacific. For the tropical mean, these opposite regional trends balance each other out resulting in a relatively weak positive trend of 0.017 ± 0.012 ppt Br/dec for 1979–2013, corresponding 3 % Br/dec. The overall contribution of CHBr3 together with CH2Br2 to the stratospheric halogen loading accounts for 4.7 ppt Br, in good agreement with existing studies, with 50 %/50 % being injected in form of source and product gases, respectively.
Reviews and syntheses: influences of landscape structure and land uses on local to regional climate and air quality
Authors: Massad Raia Silvia , Lathière Juliette , Strada Susanna , Perrin Mathieu , Personne Erwan , Stéfanon Marc , Stella Patrick , Szopa Sophie , de Noblet-Ducoudré Nathalie
Published: June 2019

Abstract. The atmosphere and the land surface interact in multiple ways, for instance
through the radiative-energy balance, the water cycle or the
emission and deposition of natural and anthropogenic compounds. By modifying the
land surface, land use and land cover changes (LULCCs) and land management
changes (LMCs) alter the physical, chemical, and biological processes of the
biosphere and therefore all land–atmosphere interactions, from local to
global scales. Through socio-economic drivers and regulatory policies adopted
at different levels (local, regional, national, or supranational), human
activities strongly interfere in the land–atmosphere interactions, and those
activities lead to a patchwork of natural, semi-natural, agricultural, urban,
and semi-urban areas. In this context, urban and peri-urban areas, which have
a high population density, are of particular attention since land
transformation can lead to important environmental impacts and affect the
health and life of millions of people. The objectives of this review are to
synthesize the existing experimental and modelling works that investigate
physical, chemical, and/or biogeochemical interactions between land surfaces
and the atmosphere, therefore potentially impacting local/regional climate and
air quality, mainly in urban or peri-urban landscapes at regional and local
scales. The conclusions we draw from our synthesis are the following. (1) The
adequate temporal and spatial description of land use and land management
practices (e.g. areas concerned, type of crops, whether or not they are
irrigated, quantity of fertilizers used and actual seasonality of
application) necessary for including the effects of LMC in global and even
more in regional climate models is inexistent (or very poor). Not taking into
account these characteristics may bias the regional projections used for
impact studies. (2) Land–atmosphere interactions are often specific to the
case study analysed; therefore, one can hardly propose general solutions or
recommendations. (3) Adaptation strategies, proposed after
climatic impacts on the targeted resource have been derived, are often
biased as they do not account for feedbacks on local/regional climate.
(4) There is space for considering atmospheric chemistry, through
land–atmosphere interactions, as a factor for land management, helping to
maintain air quality and supporting ecosystem functioning. (5) There is a
lack of an integrated tool, which includes the many different processes of
importance in an operational model, to test different land use or land management scenarios at the scale of a territory.
Exogenous phosphorus compounds interact with nitrogen availability to regulate
dynamics of soil inorganic phosphorus fractions in a meadow steppe
Authors: Liu Heyong , Wang Ruzhen , Wang Hongyi , Cao Yanzhuo , Dijkstra Feike A. , Shi Zhan , Cai Jiangping , Wang Zhengwen , Zou Hongtao , Jiang Yong
Published: June 2019

Abstract. Here we investigated the effects of P compounds (KH2PO4 and Ca(H2PO4)2) with different addition rates of 0, 20, 40, 60, 80 and 100 kg P ha−1 yr−1 and NH4NO3 addition (0 and 100 kg N ha−1 yr−1) on soil labile (Olsen-P), moderate-cycling and recalcitrant inorganic phosphorus (IP) fractions in a calcareous grassland of northeastern China. Soil moderate-cycling IP, not readily available to plants but transforming into available P quickly, include variscite (Al-P), strengite (Fe-P), dicalcium phosphate (Ca2-P) and octacalcium phosphate (Ca8-P); recalcitrant fractions include hydroxylapatite (Ca10-P) and occluded P (O-P). Soil labile and moderate-cycling IP fractions and total P significantly increased with increasing P addition rates, with higher concentrations detected for KH2PO4 than for Ca(H2PO4)2 addition. Combined N and P treatments showed lower moderate-cycling IP fractions compared to ambient N conditions due to enhanced plant productivity. Moderate-cycling IP was mainly regulated by aboveground plant biomass with KH2PO4 addition, while by soil pH and plant biomass with addition of Ca(H2PO4)2. Ca(H2PO4)2 addition significantly increased the soil recalcitrant IP (Ca10-P) fraction, while KH2PO4 addition showed no impact on it. A significant positive correlation was detected between soil moderate-cycling IP fractions and soil Olsen-P which illustrated that moderate-cycling IP fractions were important sources for available P. Our results suggest that moderate-cycling IP fractions are essential for grassland P biogeochemical cycling and chemical form of P fertilizer should be considered during fertilization management for maintaining soil available P.
Improving non-representative-sample prediction of forest
aboveground biomass maps: A combined machine
learning and spatial statistical approach
Authors: Dai Shaoqing , Zheng Xiaoman , Gao Lei , Zuo Shudi , Chen Qi , Wei Xiaohua , Ren Yin
Published: June 2019

Abstract. High-precision prediction of large-scale forest aboveground biomass (AGB) is important but challenging on account of the uncertainty involved in the prediction process from various sources, especially the uncertainty due to non-representative sample units. Usually caused by inadequate sampling, non-representative sample units are common and can lead to geographic clusters of localities. But they cannot fully capture complex and spatially heterogeneous patterns, in which multiple environmental covariates (such as longitude, latitude, and forest structures) affect the spatial distribution of AGB. To address this challenge, we propose herein a low-cost approach that combines machine learning with spatial statistics to construct a regional AGB map from non-representative sample units. The experimental results demonstrate that the combined methods can improve the accuracy of AGB mapping in regions where only non-representative sample units are available. This work provides a useful reference for AGB remote-sensing mapping and ecological modelling in various regions of the world.
Nitrous oxide (N2O) and methane (CH4) in rivers and estuaries of northwestern Borneo
Authors: Bange Hermann W. , Sim Chun Hock , Bastian Daniel , Kallert Jennifer , Kock Annette , Mujahid Aazani , Müller Moritz
Published: June 2019

Abstract. Nitrous oxide (N2O) and methane (CH4) are atmospheric trace gases which play important roles of the climate and atmospheric chemistry of the Earth. However, little is known about their emissions from rivers and estuaries which seem to contribute significantly to the atmospheric budget of both gases. To this end concentrations of N2O and CH4 were measured in the Rajang, Maludam, Sebuyau and Simunjan Rivers draining peatland in northwestern (NW) Borneo during two campaigns in March and September 2017. The Rajang River was additionally sampled in August 2016 and the Samusam and Sematan Rivers were additionally sampled in March 2017. The Maludam, Sebuyau, and Simunjan Rivers are typical "blackwater" rivers with very low pH, very high dissolved organic carbon (DOC) concentrations and very low O2 concentrations. The spatial and temporal variability of N2O and CH4 concentrations (saturations) in the six rivers/estuaries was large and ranged from 2.0 nmol L−1 (28 %) to 41.4 nmol L−1 (570 %) and from 2.5 nmol L−1 (106 %) to 1372 nmol L−1 (57,459 %), respectively. We found no overall trends of N2O with O2 or NO3−, NO2−, NH4+ and there were no trends of CH4 with O2 or dissolved nutrients or DOC. N2O concentrations showed a positive linear correlation with rainfall. We conclude, therefore, that rainfall is the main factor determining the riverine N2O concentrations since N2O production/consumption in the "blackwater" rivers themselves seems to be unlikely because of the low pH. In contrast CH4 concentrations showed an inverse relationship with rainfall. CH4 concentrations were highest at salinity = 0 and most probably result from methanogenesis as part of the decomposition of organic matter under anoxic conditions. We speculate that CH4 oxidation, which can be high when the water discharge is high (e.g. after rainfall events), is responsible for the decrease of the CH4 concentrations along the salinity gradients. The rivers and estuaries studied here were an overall net source of N2O and CH4 to the atmosphere. The total annual N2O and CH4 emissions were 1.09 Gg N2O yr-1 (0.7 Gg N yr-1) and 23.8 Gg CH4 yr-1, respectively. This represents about 0.3–0.7 % of the global annual riverine and estuarine N2O emissions and about 0.1–1 % of the global riverine and estuarine CH4 emissions. Therefore, we conclude that rivers and estuaries in NW Borneo –despite the fact their water area covers only 0.05 % of the global river/estuarine area– contribute significantly to global riverine and estuarine emissions of N2O and CH4.
A south Atlantic island record uncovers shifts in westerlies and hydroclimate during the last glacial
Authors: Björck Svante , Sjolte Jesper , Ljung Karl , Adolphi Florian , Flower Roger , Smittenberg Rienk H. , Kylander Malin E. , Stocker Thomas F. , Holmgren Sofia , Jiang Hui , Muscheler Raimund , Afrifa Yamoah K. K. , Rattray Jayne E. , Van der Putten Nathalie
Published: June 2019

Abstract. The period 36–18 ka was a dynamic phase of the last glacial, with large climate shifts in both hemispheres. Through the bipolar seesaw, the Antarctic Isotope Maxima and Greenland DO events were part of a global concert of large scale climate changes. The interaction between atmospheric processes and Atlantic meridional overturning circulation (AMOC) is crucial for such shifts, controlling upwelling- and carbon cycle dynamics, and generating climate tipping points. Here we report the first temperature and humidity record for the glacial period from the central South Atlantic (SA). The presented data resolves ambiguities about atmospheric circulation shifts during bipolar climate events recorded in polar ice cores. A unique lake sediment sequence from Nightingale Island at 37° S in the SA, covering 36.4–18.6 ka, exhibits continuous impact of the Southern Hemisphere Westerlies (SHW), recording shifts in their position and strength. The SHW displayed high latitudinal and strength-wise variability 36–31 ka locked to the bipolar seesaw, followed by 4 ka of slightly falling temperatures, decreasing humidity and fairly southern westerlies. After 27.5 ka temperatures decreased 3–4 °C, marking the largest hydroclimate change with drier conditions and a variable SHW position. We note that periods with more intense and southerly positioned SHW are correlated with periods of increased CO2 outgassing from the ocean. Changes in the cross-equatorial gradient during large northern temperature changes appear as the driving mechanism for the SHW shifts. Together with coeval shifts of the South Pacific westerlies, it shows that most of the Southern Hemisphere experienced simultaneous atmospheric circulation changes during the latter part of the last glacial.
An 11-year (2007–2017) soil moisture and precipitation dataset from the Kenaston Network in the Brightwater Creek basin, Saskatchewan, Canada
Authors: Tetlock Erica , Toth Brenda , Berg Aaron , Rowlandson Tracy , Ambadan Jaison Thomas
Published: June 2019

Abstract. Soil moisture and precipitation have been monitored in a
hydrometeorological network situated within the Brightwater Creek basin, east
of Kenaston, Saskatchewan, Canada, since 2007. The majority of the prairie
landscape is annually cropped with some sections in pasture. This
agricultural region is ideal for remote-sensing validation and calibration
and, in conjunction with the flux tower situated within the network,
hydrological model validation. Remote-sensing validation collaborations have
included the European Space Agency's Soil Moisture and Ocean Salinity (SMOS) and
NASA's Soil Moisture Active Passive (SMAP). The network was developed at two
spatial scales, one high-resolution set of sites installed over a
10 km × 10 km region and a second installed over
40 km × 40 km. The sites are all similar in design with three
instrument depths for soil moisture and temperature, as well as precipitation
measurement. The 2007–2017 dataset published in this paper has gone through
a quality control review process, which involved both automated and manual
processes. The dataset is limited to the summer months (1 May–30 September)
due to the uncertainties and complexities of measurement in frozen soils and
the freeze–thaw period each year. Data discussed in this publication are
available at https://doi.org/10.20383/101.0116, and data beyond 2017 can be requested
from the corresponding author.
A low-cost autonomous rover for polar science
Authors: Hoffman Andrew O. , Steen-Larsen Hans Christian , Christianson Knut , Hvidberg Christine
Published: June 2019

Abstract. We present the developmental considerations, design, and deployment of an
autonomous modular terrestrial rover for ice-sheet exploration that is
inexpensive, easy to construct, and allows for instrumentation
customization. The total construction cost for this rover is less than USD 3000,
approximately one-tenth the cost of existing platforms, and it can be built
using facilities frequently available at academic institutions (machine
shop, 3-D printer, open-source hardware and software). Instrumentation
deployed on this rover can be customized; the rover presented in this study
was equipped with a dual-frequency GPS receiver and a digital SLR camera for
constructing digital elevation models using structure-from-motion (SfM)
photogrammetry. We deployed this prototype rover on the Northeast Greenland
Ice Stream to map local variations in snow accumulation and surface
topography. The rover conducted four autonomous missions based out of the
East Greenland Ice-Core Project (EastGRIP) camp during July 2017, measuring
surface elevation transects across the hazardous ice-stream shear margins.
During these missions, the rover proved capable of driving over 20 km on a
single charge with a drawbar pull of 250 N, sufficient to tow instrumentation of up to 100 kg. The rover also acquired photographs
that were subsequently used to construct digital elevation models of a site
monitored for spatiotemporal variability in snow accumulation, demonstrating
adequate stability for high-resolution imaging applications. Due to its low
cost, low-power requirements, and simple modular design, mass deployments of
this rover design are practicable. Operation of the rover in hazardous areas
circumvents the substantial expense and risk to personnel associated with
conventional, crewed deployments. Thus, this rover is an investigatory
platform that enables direct exploration of polar environments considered
too hazardous for conventional field expeditions.
Infrasound and seismoacoustic signatures of the September 28th 2018 Sulawesi super shear earthquake
Authors: Pilger Christoph , Gaebler Peter , Ceranna Lars , Le Pichon Alexis , Vergoz Julien , Perttu Anna , Tailpied Dorianne , Taisne Benoit
Published: June 2019

Abstract. A magnitude 7.5 earthquake occurred on September 28th 2018 at 10:02:43 UTC near the city of Palu on the Indonesian island of Sulawesi. It was a shallow, strike-slip earthquake with fractures up to the surface and a rupture length of about 150 km. Moreover, this earthquake was identified as one of very few events having a super shear rupture speed. Clear and long-lasting infrasound signatures related to this event were observed by four infrasound arrays of the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty Organization as well as one national infrasound station in Singapore. Although these infrasound stations SING (Singapore), I39PW (Palau), I07AU (Australia), I40PG (Papua New Guinea) and I30JP (Japan) are located in large distances between 1800 km and 4500 km from the earthquake’s epicentral region, the observed infrasound signals associated to this event were intense, including both seismic and acoustic arrivals. The seismic-to-acoustic coupling at nearby terrain features is supposed to generate distinct infrasonic signatures clearly recordable at remote infrasound arrays. A detailed study of the event-related observations and the potential infrasound generation mechanisms is presented covering range- and time-dependent infrasound attenuation and propagation modeling, characterization of the atmospheric background conditions as well as identification of the regions of seismoacoustic activity by applying a backtracking method from the infrasound receivers to potential source regions. The back-projection of infrasonic arrivals allows to estimate that the main infrasound source region for the Sulawesi earthquake is related to the extended rupture zone and the nearby topography. This estimation and the comparison to other super shear as well as large regional earthquakes identifies no clear connection between the earthquake’s super shear nature and the strong infrasound emission.
Downscaling sea-level rise effects on tides and sediment dynamics in tidal bays
Authors: Jiang Long , Gerkema Theo , Idier Déborah , Slangen Aimée B. A. , Soetaert Karline
Published: June 2019

Abstract. Sea-level rise (SLR) not only increases the threat of coastal flooding, but also may change tidal regimes in estuaries and coastal bays. To investigate such nearshore tidal responses to SLR, a hydrodynamic model of the European Shelf is downscaled to a model of a Dutch coastal bay (the Eastern Scheldt) and forced by SLR scenarios ranging from 0 to 2 m. The results indicate that SLR induces larger increases in tidal amplitude and stronger nonlinear tidal distortion in the bay compared to the adjacent shelf sea. Under SLR, the basin shifts from a mixed flood- and ebb-dominant state to complete ebb-dominance, causing enhanced sediment export and accelerated loss of tidal flats. In this case study, we find that local impacts of SLR can be highly spatially-varying and nonlinear depending on basin geometry. Our model downscaling approach is widely applicable for establishing local SLR projections in estuaries and coastal bays.
Variations in soil chemical and physical properties explain basin-wide variations in Amazon forest soil carbon densities
Authors: Quesada Carlos Alberto , Paz Claudia , Oblitas Mendoza Erick , Phillips Oliver , Saiz Gustavo , Lloyd Jon
Published: June 2019

Abstract. We investigate the edaphic, mineralogical and climatic controls of soil organic carbon (SOC) concentration utilising data from 147 pristine forest soils sampled in eight different countries across the Amazon Basin. Sampling across 14 different World Reference Base soil groups our data suggest that stabilisation mechanism varies with pedogenetic level. Specifically, although SOC concentrations in Ferralsols and Acrisols were best explained by simple variations in clay content – this presumably being due to their relatively uniform kaolinitic mineralogy – this was not the case for less weathered soils such as Alisols, Cambisols and Plinthosols for which interactions between Al species, soil pH and litter quality seem to be much more important. SOC fractionation studies further showed that, although for more strongly weathered soils the majority of SOC is located within the aggregate fraction, for the less weathered soils most of the SOC is located within the silt and clay fractions. It thus seems that for highly weathered soils SOC storage is mostly influenced by surface area variations arising from clay content, with physical protection inside aggregates rendering an additional level of protection against decomposition. On the other hand, most of SOC in less weathered soils is associated with the precipitation of aluminium-carbon complexes within the fine soil fraction and with this mechanism enhanced by the presence of high levels of aromatic, carboxyl-rich organic matter compounds. Also examined as part of this study were a relatively small number of arenic soils (viz. Arenosols and Podzols) for which there was a small but significant influence of clay and silt content variations on SOM storage and with fractionation studies showing that particulate organic matter may accounting for up to 0.60 of arenic soil SOC. In contrast to what were in all cases strong influences of soil and/or litter quality properties, after accounting for these effects neither wood productivity, above ground biomass nor precipitation/temperature variations were found to exert any significant influence on SOC stocks at all. These results have important implications for our understanding of how Amazon forest soils are likely to respond to ongoing and future climate changes.
Becoming Caregivers: Companion Robots and Instructions for Use
Authors: Caudwell Catherine Barbara
Published: June 2019

Concerns and speculations about relationships between humans and robots cross disciplinary bounds, from engineering and design to popular culture, ethics, and philosophy. While there is abundant material on the appearance, function, and interaction of social robots as objects, there is an absence of discussion and research addressing the instruction manuals, packaging, and marketing material that contextualize the relationship between robots and people. Instruction manuals, a form of technical communication, are where some of the first introductions are made between robots and their caregivers, and where the boundaries for their relationship are first laid out. The study of technical communication itself is well established—a cultural perspective on this topic is rare—but vital in assessing the cultural, political, and ethical dimensions of technology. Through a case study of Furby, an early example of a simple, companionable robot, this research explores the role that instruction manuals, and other related ephemera play in defining relationships with robots, and suggests an approach for analyzing artificial companionship as it develops into new and more complex forms.
Comparación de dos métodos rápidos para la detección de Salmonella spp. con un método convencional
Authors: Burgos Jessica Tatiana , Alberti Claudia Lissette
Published: June 2019

Introducción. Uno de los microorganismos relacionados a las enfermedades transmitidas por alimentos a nivel mundial es Salmonella spp. El control sanitario de este patógeno es una de las principales preocupaciones en salud pública. La detección de Salmonella spp se realiza principalmente por métodos convencionales de cultivo y métodos rápidos automatizados, la diferencia entre ellos se centra en el tiempo de emisión de resultados. Los métodos automatizados son más rápido que los convencionales, tener los resultados en menos tiempo, es importante en salud pública. Objetivos. Comparar el desempeño de dos métodos rápidos para la detección de Salmonella spp, el método de reacción de la cadena de la polimerasa Assurance GDS System, y el inmunoensayo visual VIA TECRA, con el método convencional para la detección de Salmonella spp ISO 6579:2002, IDT, considerado de referencia internacional. Metodología. Se analizaron 96 muestras de carne fresca de pollo, proveniente de supermercados del área metropolitana de San Salvador. Las muestras fueron analizadas simultáneamente por los tres métodos en estudio. Se realizaron los cálculos de sensibilidad, especificidad, tasa de falsos positivos, tasa de falsos negativos y Chi cuadrado descrito por McNemar. Resultados. El método alternativo inmunoensayo, obtuvo los mejores resultados al compararlo los resultados del método convencional, se obtuvo un 88% de exactitud relativa, 88% de sensibilidad, un 86% de especificidad, 14% de tasa de falsos positivos y un 12% de tasa de falsos negativos, mientras que al realizar la comparación con el metodo Assurance GDS System se obtuvo un 85% de sensibilidad, un 81% de especificidad, 19% de tasa de falsos positivos y un 15% de tasa de falsos negativos. Al evaluar los datos discordantes y aplicar el test de Chi cuadrado, se determinó que no existe diferencia significativa entre los métodos evaluados (P≤0.05). Conclusiones. El método alternativo inmunoensayo visual, obtuvo los mejores resultados contra el método convencional.
Aplicación del sistema integrado de manufactura en los procesos productivos en la empresa Joya de Nicaragua, S.A. 2018
Authors: Lanuza Martínez Ángela María , Peralta Calderón Yirley Indira
Published: June 2019

El trabajo investigativo elaborado en la empresa Joya de Nicaragua, S.A., se llevó a cabo con el propósito de valorar la “Implementación del sistema integrado de manufactura en los procesos productivos en la empresa Tabacalera Joya de Nicaragua, S.A. durante el año 2018”. En base al problema de investigación y los objetivos propuestos, el enfoque es cualitativo de tipo correlaciones causales. Es un estudio de alcance explicativo porque se centra en estudiar la relación de la implementación del sistema integrado de manufactura en los procesos productivos, y a partir de ellos fortalecer las estrategias empresariales. En la investigación se emplearon métodos teóricos y prácticos para elaborar instrumentos que permitieran recopilar toda la información oportuna, estos fueron: guía de entrevista, guía de revisión documental, guía de observación y grupos focales. Donde se logra identificar que los procesos productivos están bajo las características de procesos por lotes, y a lo largo de ellos se implementan parcialmente técnicas de manufactura esbelta como: control de calidad, seis sigma, sistema matricial de control interno, mejoramiento de la productividad y ciclo de Deming. Concluyendo este estudio, que para lograr la efectividad del sistema integrado de manufactura, es necesario fortalecer el control interno administrativo e implementar el plan de propuesta de estrategia, basado en las estrategias de funciones y estrategias corporativas, que garantizara la documentación de toda la información que se genera en los procesos productivos, asistiendo a la alta gerencia para tener más detalle de toda la información que le permitirá la toma de decisiones.
Carved Into History: The Vernacular Rock Inscriptions of the Connecticut Valley
Authors: LeTourneau Peter M. , Pagini Robert
Published: June 2019

This study is the first comprehensive analysis of the unexpectedly rich collection of informal inscriptions carved into the basalt lava (traprock) cliffs and promontories of the Connecticut Valley. An analysis of the tools and techniques used to produce the inscriptions, and problems in documenting and conserving the historic rock carvings are presented. The vernacular inscriptions range from unskilled scratching of the weathered surfaces with objects “at hand,” to deep carvings executed by master stonecutters using hardened steel masonry chisels. Although the earliest carvings date from the late 1700s, the peak period for traprock inscriptions spans from about 1830 to 1920, coincident with the rise of landscape tourism in the Connecticut Valley. Inscriptions produced throughout the nineteenth century characteristically display well-balanced lettering with bold serifs, reversed letters and numerals, graphic ornamentation, and frames and enclosures all produced by confident, if not skilled, hands. In contrast, since the mid-twentieth century, most inscriptions are crude devices. The different styles are ascribed to cultural trends and the ages of the carvers. Comparison to contemporaneous inscriptions from other areas suggests that the vernacular custom of carving personal badges, or “tagging,” places of scenic or historic interest was widely practiced in the early to mid-nineteenth century.

A number of inscriptions have been assigned to likely or known carvers based on often surprisingly robust threads of geographical, historical, and anecdotal evidence, or personal communications. The regional practice of carving personal identifiers and calendar dates at popular promontories and scenic overlooks was primarily a response to the unique physical geography of the region. The weathered rock surfaces on the sheer cliffs and rugged ledges provided both the motivation and opportunity for the placement of inscriptions, originally as placed as idle scratchings, but later, through the nineteenth century, as skillfully chiseled carvings. The puzzling absence of Native American rock wall petroglyphs in the study area is explored in context of the rich collection of historic inscriptions and the relatively limited culture of indigenous rock art from the region. The vernacular culture of rock carving was also influenced tangentially by national and global developments in geographic exploration, the rise of landscape tourism, emerging attitudes about the transcendental qualities of nature, as well as practicalities including high rates of literacy and the proliferation of technical and mechanical skills in the region. Problems of conservation and methods of obtaining facsimile copies of the traprock inscriptions are discussed.
Prefiguring as an Indigenous Narrative Tool in Nigerian Cinema: An Ethnomusicological Reading
Authors: Sylvanus Emaeyak Peter
Published: June 2019

Prefiguring entails the use of music to predict dialogue and scenes in film. It is prevalent in the cinematic productions of both the ethnic-based film industries in Nigeria and mainstream Nollywood. Theoretically, prefiguring is a function of indigenous storytelling practices, the appropriation of which conjures up layers of meaning for the local practice, practitioners, and audiences. Relying on in-depth textual analyses, composers’ accounts, and relevant literature, I argue that prefiguring is a concept of major theoretical importance to the study of music in Nigerian cinema, not least because its existence and efficacy strongly support notions of a localized film music practice.
Singing as Justice:Ateetee, an Arsi Oromo Women’s Sung Dispute Resolution Ritual in Ethiopia
Authors: Qashu Leila
Published: June 2019

This article explores how singing and ritual can constitute justice. Specifically, I look at how Arsi Oromo women in Ethiopia use ateetee, a sung indigenous women’s dispute resolution process, to protect, defend, promote, and assert their rights. I use thick descriptive ethnography, narratives, and experiences from fieldwork, musico-poetic analyses, and the voices of Arsi Oromo community members to explore how the sung ateetee ritual is a necessary and effective means for Arsi women to claim their rights in rapidly changing social environments.