bluuebunny/crossref_metadata_2025 huggingface dataset:
Lattice vibrations of the molecular crystal of photoreactive substance with defects
Authors: Syetov Y.
Published: June 2020

Lattice vibrations are studied theoretically by density-functional based tight-binding methods for the model structure of 2-(2'-hydroxyphenyl)benzoxazole crystal with defects. 2-(2'-hydroxyphenyl)benzoxazole is a photoreactive compound that exhibits excited state intramolecular proton transfer in the structure with an OH...N hydrogen bond. The unit cell of the model structure consists of two crystal unit cells where the molecules have the structure with intramolecular hydrogen bonds OH...N and one molecule is supposed to have a different orientation of the whole molecule or its fragment. The different orientation of the fragment forms the structure with an intramolecular hydrogen bond OH...O. It is calculated that defect caused by the different orientation of the molecule have a lower energy than the defect caused by the different orientation of the fragment. In the frequency region where the contribution of external vibrations of the molecules is significant, the vibrations mainly involve several molecules in the cell. In the region of internal vibrations there are modes, which are local vibrations of the defects. These local vibrations involve mainly motion of the atoms constituting the defect molecule. The number of local vibrations is larger for the defect that corresponds to the formation of the structure with the OH...O hydrogen bond than for the defect that corresponds to the different  orientation of the whole molecule with the OH...N hydrogen bond. The internal vibrations of the defect molecule formed by the different orientation of phenol fragment in the lattice undergoes frequency shift in relation to the frequency of the modes of isolated molecule.
Conductivity of grains in nonlinear oxide ceramics and protective properties of varistors
Authors: Ivon A. I. , Lavrov R. I.
Published: June 2020

The current-voltage characteristics of various compositions of nonlinear varistor ceramics based on ZnO (ZOC) and SnO2 (TOC) are studied in a wide range of electric current. On the basis of obtained data were determined the parameters that allow finding the coefficients kprs and kprl, which define the protection  levels against the switching surge and the lightning surge for surge suppressors on the basis of ZOC and TOC varistors. The lower the value of these coefficients are, the significantly higher the efficiency of surge protection is. A relationship between kprs, kprl, and the effective linear resistivity ρlin limiting the current of intergranular barriers in varistor ceramics are established. It is shown that the values of kprs and kprl increase with increasing ρlin, which value is determined by the bulk resistance of the ceramic grains. The studied TOC compositions have 2-3 times larger values of ρlin and more high values of kprs and kprl than ZOC. ZOC-based varistors with lower kprs and kprl values provide more effective surge protection than TOC-based varistors.
Millimeter wave patch antenna array for 5G wireless communication systems
Authors: Gnilenko A. B. , Plaksin S. V.
Published: June 2020

Millimeter waves are now considered as an important part of 5G spectrum. Higher frequencies provide larger bandwidth giving the ability to support very high data rate, ultra high capacity and very low latency. The utilization of millimeter wave frequency bands for 5G mobile applications requires effective solutions in the design of antennas and antenna arrays which are the key parts of modern communication systems. In this paper a 4x4 microstrip patch antenna array sub-module is presented to be a part of 5G wireless communication system. The antenna array is designed and optimized to operate at a frequency of 85 GHz which corresponds to the middle of the second atmospheric transparency window. The antenna array is simulated using the time domain solver of the CST Microwave Studio software package. Simulation results are demonstrated and discussed for an optimized array. The designed patch antenna array provides good directivity characteristics with a main lobe magnitude of 16 dBi, angular width of 28 degree and can be applied as a part of a wireless communication system operating at a high frequency band of 5G frequency range.
Design of a rail–road asymmetrical low-pylon cable-stayed bridge with a main span of 588 m
Authors: Yi Lunxiong , Mei Dapeng , Zhou Cong
Published: June 2020

The Shangqiu–Hangzhou high-speed railway is 794.55 km long with a design speed of 350 km/h. The third Wuhu Yangtze River Bridge stands out as the key project of the whole railway. Restricted by the site conditions, the bridge is an asymmetrical low-pylon cable-stayed bridge with a main span of 588 m. To overcome the technical challenges of low stiffness and unfavourable axial force induced by the low pylons, a box-truss type composite section with a strong box at the lower deck and a weak truss above was creatively used in the design of the main girder. In addition, parallel steel wire cables coated with a zinc–aluminium alloy and with a tensile strength of over 2000 MPa were developed to withstand the tremendous axial force in the inclined cables. These two innovative solutions were successfully implemented in the construction of the bridge. This paper describes problem solving through creativity by addressing a few key issues faced by the designers.
Failure analysis of historic vertical breakwaters, part 2: Alderney, Guernsey and Dover, UK
Authors: Allsop Nigel William Henry , Bruce Tom
Published: June 2020

Many historic breakwaters failed early in their life, leaving little information by which to analyse or understand their failures. As part of a wider analysis of ‘old breakwaters’, the first author has analysed the ‘stability’ of example vertical breakwaters using analytical methods developed over the past 20 years. This analysis is illustrated in this and the companion paper by three case studies: Wick (designed by Thomas Stevenson, failed 1870–1877); Alderney (damaged even during construction, lost its outer length 1865–1889); and Dover (still shows high stability after 110 years). In each of these case studies, representative cross-sections have been derived from historical records, as have the approach bathymetry. Representative wave conditions are transformed to the breakwater toes, including depth-limiting and impulsive breaking effects. Empirical formulae developed during and since the PROVERBS (Probabilistic Design Tools for Vertical Breakwaters) project have been used to explore incidence of wave impact loads, the main momentum loads and impulsive loads. Factors of safety against sliding and/or overturning have been determined for each example over a range of representative wave conditions.
Study on transient unloading loosening simulation test of excavation of jointed rock mass
Authors: Luo Yi , Huang JunHong , Lu WenBo , Zhang Guang , Li XinPing , Song KaiWen
Published: June 2020

Based on the abrupt displacement of a jointed surrounding rock mass during blasting excavation of deep underground caverns, a set of transient unloading loosening simulation tests was designed for multi-joint rock masses. Through the linear regression analysis of the unloading displacement of jointed rock masses, the opening displacement of a joint is determined to be proportional to the square of the initial unloading stress. The numerical simulation method is used to apply horizontal and vertical in situ stresses to the jointed rock mass model to study the opening displacement in the jointed rock mass at different lateral pressure coefficients of in situ stress. The results indicate that, with the unloading of the horizontal stress, a larger lateral pressure coefficient of the in situ stress leads to a larger opening displacement in the jointed rock mass. When the vertical stress is unloaded after the horizontal stress is totally unloaded, a lower lateral pressure coefficient of the in situ stress leads to a larger opening displacement. The influence of the stress lateral pressure coefficient on the open deformation of the jointed rock mass is obviously higher than that of the unloading rate on the rock mass.
Soil sounding location optimisation for spatially variable soil
Authors: Chwała Marcin
Published: June 2020

A novel approach for estimating foundation bearing capacity, conditioned by soil sounding locations in the case of spatially variable soil properties, is proposed in the study. This method uses a kinematic approach in conjunction with Vanmarcke spatial averaging, which substantially improves the numerical efficiency when solving three-dimensional problems over that of existing methods. Therefore, the approach can be used in optimisation procedures dedicated to the search for optimal soil sounding locations – that is, the locations for which the lowest possible bearing capacity standard deviation is obtained. This paper provides a complete algorithm for considering soil soundings in the bearing capacity estimation of rectangular foundations. The application of the algorithm for two soil sounding locations is described in this study, the obtained numerical efficiency is very high; namely, one bearing capacity estimation of a rectangular foundation takes approximately 0·5 s on a standard notebook. The potential applications of this algorithm are also discussed in the study.
Decision making methods to prioritise asset-management plans for municipal infrastructure
Authors: Amador-Jimenez Luis , Mohammadi Alireza
Published: June 2020

This paper proposes a methodology for measuring and comparing the benefits associated with a change in the decision making method for infrastructure asset management. Three common methods of measuring are reactive approach (also known as worst-first), silos and trade-off optimisation. A case study is used to illustrate the impact of applying different decision making approaches. The case is based on the urban municipality of the Town of Kindersley, Canada, and contains pavements and water main, storm sewer and sanitary sewer pipes. Economic comparisons of (a) the observed levels of service under fixed budgets and (b) the expenditure required to achieve the target levels of service are presented to support the selection of the preferred decision making method and to measure the superiority of one approach over another. Results from the analysis confirmed the expected inferiority of the worst-first method. Applying the trade-off method resulted in the expenditure of 8.83% fewer resources than the use of the silo method. For a yearly budget of C$800 000 (US$590 695) applied to all types of infrastructure, the trade-off resulted in mean condition levels 12.9% higher than those resulting from the silo method. The proposed platform can be applied to other infrastructure using different performance indicators.
Who Owns U.S. CLO Securities? An Update by Tranche
Authors: DeMarco Laurie , Liu Emily , Schmidt-Eisenlohr Tim
Published: June 2020

Against the backdrop of the COVID-19 crisis, leveraged loans have deteriorated and concerns about CLOs, the main buyers of loans on the secondary market, have increased. These concerns have reduced the demand for new CLOs, making it harder for firms to borrow through leveraged loans on the primary market, as banks have found it more difficult to sell loans on the secondary market.
Enoturismo no Brasil: um estudo comparativo dos perfís dos enoturistas do Vale dos Vinhedos e do Vale de São Francisco
Authors: Dal Rosso Lima Bárbara , Ribeiro José Cadima , Nunes Vinícius Pinheiro
Published: June 2020

O enoturismo tem apresentado importância crescente, mostrando-se como alternativa de desenvolvimento para as regiões vitivinícolas. Entretanto, a literatura aponta a existência de uma lacuna de informação sobre as caraterísticas e comportamentos dos visitantes. Em razão disso, o presente estudo tem como objetivo principal determinar o perfil dos visitantes da regiões vitivinícolas brasileiras do Vale dos Vinhedos e do Vale de São Francisco. Recorreu-se a dados qualitativos e quantitativos sobre os enoturistas. Os inquéritos foram aplicados aos turistas que visitaram essas regiões vinícolas e os dados foram submetidos a técnicas estatísticas multivariadas com o objetivo de segmentar os visitantes. Os resultados apontam que as visitas podem ter diferentes motivações. Percebeu-se, também, que os turistas encontrados no Vale dos Vinhedos e no Vale de São Francisco têm perfis distintos. Em matéria de estratificação, obtiveram-se quatro segmentos: apaixonados; interessados; visitantes ocasionais; e indiferentes. Os resultados da investigação sugerem que conhecer melhor o perfil do enoturista possibilita a implementação de novas estratégias de marketing e ajuda a formatar a oferta.
Condições de acesso à linha do Pronaf Agroecologia no Território da Cantuquiriguaçu/PR
Authors: Stoffel Janete , Rambo Anelise Graciele , Eberhardt Patrícia Luiza
Published: June 2020

Com a instituição do Programa Nacional de Fortalecimento da Agricultura Familiar em 1995, os recursos financeiros voltados para a agricultura familiar passaram a ter um canal de acesso antes inexistente. Dentre os subprogramas do Pronaf está a linha voltada para a agroecologia, instituída a partir da safra 2003/2004, cujo acesso é baixo. Neste contexto o artigo aqui apresentado resulta de uma pesquisa que busca analisar limites e potencialidades no acesso dos agricultores familiares à linha do Pronaf Agroecologia no Território da Cidadania da Cantuquiriguaçu/PR. Foi utilizado instrumental descritivo exploratório, via um estudo de casos coletando dados junto a agricultores familiares e com agentes de instituições financeiras, buscando confrontar e comparar as respostas sobre a inexistência de acesso ao subprograma na região. Os resultados indicam que os agricultores familiares entrevistados, têm interesse em acessar os recursos, mas por desconhecimento, dificuldades quanto às exigências, receio quanto ao endividamento e taxas de juros, isto não acontece. No caso das instituições financeiras o que se observou é de que a linha não é atraente em termos financeiros para ser disponibilizada. Consequentemente não há um conhecimento apurado sobre como funciona e constata-se a necessidade de que a assistência técnica seja mais efetiva no sentido de instruir, orientar e auxiliar os agricultores familiares a apresentar projetos viáveis junto às instituições financeiras. Superar estes limites pode ser um meio de usufruir das potencialidades da produção agroecológica, tão importante e necessária para a sustentabilidade social, ambiental e econômica.
Análise do processo de incorporação de cooperativas
Authors: Gonçalves Roberto Birch , Benato Aline Busetti
Published: June 2020

O cooperativismo é um movimento capaz de unir desenvolvimento econômico e bem-estar social, tendo como pilares fundamentais uma participação democrática, solidariedade, independência e autonomia; portanto, a participação dos membros da cooperativa é importante para o desempenho e a boa gestão. A modernização da cooperação assume diferentes formas de negócios, o que torna necessário que as cooperativas busquem alternativas e estratégias de gestão para a sociedade cooperativa como um todo, uma das quais é a incorporação. Nesse sentido, o objetivo deste trabalho é analisar o processo de incorporação de cinco cooperativas que formaram uma nova cooperativa, analisada pelo ponto de vista do associado. Para isso, foi realizada uma pesquisa descritiva com abordagem quantitativa (survey) que permitiu verificar e apresentar um diagnóstico da percepção dos associados sobre a cooperativa resultante da incorporação, através de 248 questionários válidos. O questionário foi construído em quatro dimensões: gestão cooperativa, gestão de associados, infraestrutura e treinamento técnico agrícola. Os resultados mostram as percepções gerais dos associados e apontam a importância do atendimento, gestão, infraestrutura e assistência técnica, como os principais responsáveis pela satisfação, confiança e comprometimento dos associados.
O Programa Nacional de Alimentação Escolar em Santana do Livramento (RS): Desafios para a Adequação à Lei dos 30%
Authors: Troian Alessandra , Breintenbach Raquel
Published: June 2020

O Programa Nacional de Alimentação Escolar (PNAE) é uma importante política pública de alimentação e nutrição no Brasil. Ao estabelecer legalmente que 30% dos recursos federais repassados para a merenda escolar devem ser empregados na compra de produtos da agricultura familiar, contribui para o fortalecimento da categoria social e para o desenvolvimento local. Neste sentido, a pesquisa visa analisar como Santana do Livramento tem usado os recursos do PNAE e elencar os entraves e desafios na aquisição dos alimentos diretamente da agricultura familiar. Metodologicamente a pesquisa caracteriza-se como mista, com a coleta e análise de dados secundários obtidos no sítio oficial do Fundo Nacional de Desenvolvimento da Educação e dados primários, a partir de entrevistas. No período de 2010 a 2017 o município não cumpriu a Lei nº 11.947/2009, chegando ao máximo de utilização de 19,49% do recurso do PNAE para a compra direta da agricultura familiar. Os principais entraves para o cumprimento da lei são: burocracia, elaboração e divulgação dos editais, preços dos produtos, falta de documentação da agricultura familiar e desconhecimento dos gestores acerca dos alimentos produzidos localmente.
Refeições e comportamentos à mesa: um estudo a partir de consumidoras urbanas
Authors: Gazolla Marcio , Viecelli Pahola Cristiny
Published: June 2020

O objetivo desse estudo é discutir as dinâmicas e os comportamentos alimentares acerca do consumo das principais refeições realizadas no ambiente doméstico de consumidoras urbanas do Município de Pato Branco/PR. Para isso, a metodologia quanti/qualitativa foi construída a partir de uma pesquisa de campo realizada com 43 consumidoras pré-selecionadas de acordo com seu perfil socioeconômico e local de moradia. O instrumento de pesquisa foi um questionário, baseado em questões de múltipla escolha, aplicado individualmente no domicílio de cada participante. Utilizou-se ainda de diário de observação de campo, registrando impressões da pesquisadora a partir de falas e depoimentos das interlocutoras. Os resultados indicam que as refeições realizadas ao redor da mesa representam, simbolicamente, uma prática importante como espaço da família, das conversas, da troca de informações e de diálogos que servem também como forma de sociabilidade do grupo domiciliar. Além disso, lançar luz sobre a estrutura das refeições contemporâneas, possibilitou compreender que as transformações do comer decorrentes da modernidade alimentar – evidenciada por um movimento de maior homogeneização e individualização da alimentação – não se limitam unicamente a reprodução das condições alimentares de contextos hegemônicos e dos interesses agroindustriais.
Indicações geográficas, capital social e desenvolvimento territorial
Authors: Dos Anjos Flávio Sacco , Da Silva Fernanda Novo , Caldas Nádia Velleda
Published: June 2020

Esse artigo aborda a questão da construção dos sinais distintivos de mercado, mormente das indicações geográficas de produtos agroalimentares como um instrumento para o desenvolvimento dos territórios e/ou das regiões essencialmente rurais. A abordagem leva em conta duas experiências relativas ao estado do Rio Grande do Sul a partir de uma análise comparativa que expõe seus respectivos avanços e debilidades. A pesquisa baseou-se em entrevistas realizadas entre os anos 2008 e 2012 com diversos atores sociais ligados a ambas as iniciativas. O estudo mostra que isoladamente tais dispositivos não são suficientes para a ampliação dos horizontes em regiões marcadas por uma racionalidade individualista e pouco aberta à cooperação.
Pandemics, privacy, and public health research
Authors: Bernier Alexander , Knoppers Bartha Maria
Published: June 2020

Sharing data expediently for pandemic response purposes exposes healthcare providers in Canada to significant regulatory uncertainty. Duplicative and contradictory ethical and legal duties flowing from overlapping sources can stifle flows of medical data among clinicians, researchers, and institutions. Authorities should support caregivers and accelerate research by providing clear guidance to the health sector. Institutions should foster robust data stewardship and standardize their practices to those recognized among the international health informatics community. Reform is critical to ensuring Canadian healthcare providers can deliver efficient health responses that are integrated with dispersed and disparate national and international approaches.
Datenmodelle in Cloud-Plattformen
Authors: Grund Christian , Wenz Samuel , Barth Timo
Published: June 2020

Cloud-Plattformen werden in der industriellen Anwendung immer relevanter. Sie dienen sowohl als Datenablage, nehmen jedoch zunehmend auch Modellierungs-, Strukturierungs- und Austauschaspekte, sowohl für Engineering- als auch für Live-Daten wahr. In diesem Beitrag wird eine praxisnahe Anwendung vorgestellt, mithilfe derer Ingenieure in der Lage sind, die stetig steigende Anzahl von Daten in der Cloud sinnvoll abzubilden. Vorlage bilden hierzu bestehende Strukturen in Planungs-(CAE) bzw. Engineering-Systemen der Automatisierungstechnik und des Anlagenbaus. Das hierfür entwickelte Werkzeug „VisualHierarchy Modeller“ wird durch die Autoren am Beispiel der Cloudplattform MindSphere der Siemens AG vorgestellt. Dabei werden im gesamten Beitrag Analogien zur klassischen Software- und Plattform-Entwicklung aufgezeigt, um die angewendeten Konzepte sinnvoll zu klassifizieren.
Eine systematische Bewertung der Qualität von Simulationsmodellen
Authors: Barth Mike , Kübler Karl , Heinzerling Till , Rosen Roland , Jäkel Jens
Published: June 2020

Mit der fortschreitenden Entwicklung von Digitalen Zwillingen werden Simulationsmodelle immer wichtiger. Sie sind eine zentrale Komponente in der Systementwicklung und werden immer häufiger zu einem Bestandteil der Lieferung einer Anlage oder eines Produktes. Im Gegensatz zu realen Komponenten, deren Anforderungen in Bezug auf die geforderte Qualität sehr genau in Form von Lastenheften definiert werden, ist dies bei Simulationsmodellen aktuell selten bis gar nicht der Fall. Dies liegt zum einen an der Neuartigkeit der Simulation als eigenständigem Gut und zum anderen daran, dass keine übergreifend definierten Qualitätskriterien für Simulationsmodelle existieren. Der Beitrag nimmt sich dieser Problemstellung anund stellt den ersten Schritt in der Entwicklung einer Metrik zur objektiven Feststellung der Qualität von Simulationsmodellen vor.
Digital Visualisation as a New Driver of Urban Change in Africa
Authors: Watson Vanessa
Published: June 2020

Cities in Sub-Saharan Africa are growing faster than in any other part of the world, driven by expanding informal settlement (usually on the urban periphery) and the real-estate sector aiming for up-market property development. The continent currently has the highest real-estate value growth potential in the world. Much up-market property development is currently taking the form of new ‘cities’—sometimes a redevelopment of an entire city (e.g., Kigali), sometimes a new city on an urban edge (e.g., Eko-Atlantic, Lagos) and sometimes a new satellite city (e.g., Tatu City, Nairobi). These projects are driven by international property development companies often in collaboration with governments and sometimes with local planning and property partners. All manifest as plans in a new way: as graphics on the websites of international consultants. Most involve no public participation and attempt to by-pass planning laws and processes. Producing these new plans (as computer generated images) are a new set of professionals: architects, planners, visualisers, advertising executives and project managers, working together in offices in global capitals of the world. Their aim is commercial. Planning in these projects is no longer shaped by the materiality of the city and attempts to achieve socio-spatial justice and sustainability. Rather planning is shaped by the circulation of graphics through a network of software programmes and marketing professionals. This article will situate Africa’s new cities in theorisation of urban development and the role of urban planning through digital visualization.
Reflections on Deploying Community-Driven Visualisations for Public Engagement in Urban Planning
Authors: Weise Sebastian , Wilson Alexander , Vigar Geoff
Published: June 2020

Publicly available visualisations play an increasing role in enabling wider audiences to contribute to debates to shape place futures. In this article, we unpack such contributions to consider the conceptualisation, actualisation and deployment of these visualisations as separate entities that each require development and reflection. In doing so we draw on our experiences of using two public engagement tools that utilise visualisations of residents’ comments. Through this we explore the limitations of visualisations in public engagement designed to support differing levels of debate and their abilities to support abstract topics and geographic associations. We discuss how visualisations alone do not produce actions and how they need to be rooted in wider conversations about a place to lead to insights and action. The article calls for the linking of visualisations for place meaning and place action at different stages of much broader public engagement projects to unlock the potentials present in them in the mediatisation of built environment outcomes.
Participatory Urban Planning: What Would Make Planners Trust the Citizens?
Authors: Åström Joachim
Published: June 2020

Based on the critical stance of citizens towards urban planning, growing attention has been directed towards new forms of citizen participation. A key expectation is that advanced digital technologies will reconnect citizens and decision makers and enhance trust in planning. However, empirical evidence suggests participation by itself does not foster trust, and many scholars refer to a general weakness of these initiatives to deliver the expected outcomes. Considering that trust is reciprocal, this article will switch focus and concentrate on planners’ attitudes towards citizens. Do urban planners generally think that citizens are trustworthy? Even though studies show that public officials are more trusting than people in general, it is possible that they do not trust citizens when interacting with government. However, empirical evidence is scarce. While there is plenty of research on citizens’ trust in government, public officials trust in citizens has received little scholarly attention. To address this gap, we will draw on a survey targeted to a representative sample of public managers in Swedish local government (N = 1430). First, urban planners will be compared with other public officials when it comes to their level of trust toward citizens’ ability, integrity and benevolence. In order to understand variations in trust, a set of institutional factors will thereafter be tested, along with more commonly used individual factors. In light of the empirical findings, the final section of the article returns to the idea of e-participation as a trust-building strategy. What would make planners trust the citizens in participatory urban planning?
Digital Excavation of Mediatized Urban Heritage: Automated Recognition of Buildings in Image Sources
Authors: Mager Tino , Hein Carola
Published: June 2020

Digital technologies provide novel ways of visualizing cities and buildings. They also facilitate new methods of analyzing the built environment, ranging from artificial intelligence (AI) to crowdsourced citizen participation. Digital representations of cities have become so refined that they challenge our perception of the real. However, computers have not yet become able to detect and analyze the visible features of built structures depicted in photographs or other media. Recent scientific advances mean that it is possible for this new field of computer vision to serve as a critical aid to research. Neural networks now meet the challenge of identifying and analyzing building elements, buildings and urban landscapes. The development and refinement of these technologies requires more attention, simultaneously, investigation is needed in regard to the use and meaning of these methods for historical research. For example, the use of AI raises questions about the ways in which computer-based image recognition reproduces biases of contemporary practice. It also invites reflection on how mixed methods, integrating quantitative and qualitative approaches, can be established and used in research in the humanities. Finally, it opens new perspectives on the role of crowdsourcing in both knowledge dissemination and shared research. Attempts to analyze historical big data with the latest methods of deep learning, to involve many people—laymen and experts—in research via crowdsourcing and to deal with partly unknown visual material have provided a better understanding of what is possible. The article presents findings from the ongoing research project ArchiMediaL, which is at the forefront of the analysis of historical mediatizations of the built environment. It demonstrates how the combination of crowdsourcing, historical big data and deep learning simultaneously raises questions and provides solutions in the field of architectural and urban planning history.
Visual Communication in Urban Design and Planning: The Impact of Mediatisation(s) on the Construction of Urban Futures
Authors: Christmann Gabriela , Singh Ajit , Stollmann Jörg , Bernhardt Christoph
Published: June 2020

This editorial introduces the subject matter of the thematic issue, which includes a diverse collection of contributions from authors in various disciplines including, history, architecture, planning, sociology and geography. Within the context of mediatisation processes—and the increased use of ever-expanding I&C technologies—communication has undergone profound changes. As such, this thematic issue will discuss how far (digital) media tools and their social uses in urban design and planning have impacted the visualisation of urban imaginations and how urban futures are thereby communicatively produced. Referring to an approach originating from the media and communication sciences, the authors begin with an outline of the core concepts of mediatisation and digitalisation. They suggest how the term ‘visualisation’ can be conceived and, against this background, based upon the sociological approach of communicative constructivism, a proposal is offered, which diverges from traditional methods of conceptualising visualisations: Instead, it highlights the need for a greater consideration towards the active role of creators (e.g., planners) and recipients (e.g., stakeholders) as well as the distinctive techniques of communication involved (e.g., a specific digital planning tools). The authors in this issue illustrate how communicative construction, particularly the visual construction of urban futures, can be understood, depending upon the kind of social actors as well as the means of communication involved. The editorial concludes with a summary of the main arguments and core results presented.
Valoración de la geodiversidad del Parque Natural y Geoparque de las Sierras Subbéticas (Córdoba, sur de España)
Authors: Carruana Herrera David Isaac , Martínez Murillo Juan Francisco
Published: June 2020

El Parque Natural Sierras Subbéticas obtuvo la catalogación de geoparque de la Red Europea de Geoparques en 2006 y Geoparque de la UNESCO en 2015 gracias a su riqueza en fósiles (facies ammonitico rosso, rica en ammonites) y la presencia de muy buenos ejemplos de morfologías exo y endokársticas. La valoración de la geodiversidad en geoparques es un análisis clave para comprender su distribución espacial y, por tanto, mejorar la ordenación y la gestión de los usos en estos espacios naturales. Este trabajo tiene por objetivo valorar su geodiversidad mediante la aplicación y comparación de tres métodos basados en el álgebra de mapas. Los resultados ofrecieron una alta variabilidad espacial de la geodiversidad, con una valoración diferente en función del método empleado. Este hecho indicó la necesidad de seguir indagando en nuevos métodos que ofrezcan buenas herramientas y cartografía para la gestión por parte de los gestores de espacios naturales protegidos y geoparques.
Evaluación de la sostenibilidad de la expansión urbana de Salamanca (1956-2018) a través del análisis multitemporal de cambios de uso del suelo y análisis multicriterio
Authors: Criado Nicolás Marco , Santos-Francés Fernando , Martínez-Graña Antonio
Published: June 2020

La ausencia de sostenibilidad urbana es un déficit muy extendido en las aglomeraciones urbanas. En el presente trabajo desarrollamos una metodología que permite identificar los impactos ocasionados por la expansión urbana a lo largo del tiempo, tomando como área de estudio la ciudad de Salamanca (España) y su zona de influencia. Se realiza una evaluación multitemporal de los cambios en la cobertura del suelo mediante imágenes Landsat y teledetección, mientras que los criterios de sostenibilidad (ecológicos, agrícolas, culturales y riesgos naturales) son analizados mediante análisis multicriterio (AMC) empleando el método de las jerarquías analíticas (AHP) y Sistemas de Información Geográfica (SIG). Los resultados muestran un incremento del área urbanizada de un 635% en el periodo estudiado (1956-2018), identificándose hasta un 15% de las edificaciones en zonas con restricción. En el 71% de los casos, la urbanización provocó el sellado de suelos agrícolas fértiles (2,519 ha), de las cuales casi el 20% eran de la mayor calidad. Se identificó un aumento desmedido de la superficie urbanizada en comparación a la dinámica poblacional en los últimos años, provocando un sellado desmedido de suelos que repercute en la producción alimentaria.
Pleistocene to Holocene phases of sedimentation and soil formation in the semiarid SE Spain (Eastern Betic Cordillera)
Authors: Silva Barroso Pablo Gabriel , Roquero Elvira , Bardají Teresa , Medialdea Utande Alicia
Published: June 2020

This work uses the set of available regional geochronological data (OSL, TL, 14C, Th/U) on alluvial sediments, calcretes and soils for the semiarid SE Spain to build a theoretical time-scale for the most important phases of sedimentation and soil formation occurred in the zone from the Middle Pleistocene to the Holocene. Most of the data come from the set of paleoseismic and paleoclimatic research carried out in the regions of Murcia and Almería over the past years. The gathered geochronological data set has 168 dates, 52 for calcic soils and calcretes and 116 for sediments and covers the last c. 400 ka. The analysis is based in the construction of age-frequency distribution functions discriminating bins of 5 ka, which offer enough resolution to distinguish among different Oxygen Isotopic Stages (OIS). The Holocene dataset is analysed separately discriminating time-bins of 0.5 ka according to the more robust data-data set 14C ages. Calcretes appears as elements developed during the last stages of warm isotopic stages (OIS 9 to 1), whilst sedimentation dominated during the transition between warm-cold isotopic stages, especially during terminations II to I, coinciding with deglaciation periods. During the Holocene the climatic events of 8.2 and 2.4 ka are clearly identified as drier periods with minor sedimentation, but enhanced calcrete formation, especially the first one.
Modelamiento de Superficies en Coordenadas Esféricas a Través de GeoGebra
Authors: Osorio Alejandro I. Flores , Costa Nielce M. Lobo da , Peña Dennis A. Espejo , Montesinos Lenin R. Cabracancha
Published: June 2020

Este artículo tiene como objetivo presentar una herramienta que permita ayudar la enseñanza y el aprendizaje de graficar y describir superficies en coordenadas esféricas, a través del software libre GeoGebra, para lo cual se va representar superficies convencionales y no convencionales, así como sólidos que están limitados por un número finito de superficies por medio de parametrizaciones basadas en coordenadas esféricas y luego presentarlas en la vista gráfica 3D de GeoGebra usando el comando  Superficie, de esta forma se tiene una inmejorable visualizar, percepción, manipulación y comprensión del esbozo de superficies en el espacio en un ambiente dinámico y amigable. Finalizamos con un caso de aplicación de modelado del planetario más grande del mundo aplicando superficies paramétricas basadas en las coordenadas esféricas.
 
Palabras-clave: Modelamiento. Superficies. Parametrización. Coordenadas Esféricas. GeoGebra.
Abstract
This article aims to present a tool that aids the teaching and learning of graphing and describing surfaces in spherical coordinates, through the free GeoGebra software, for which specific and non-specific surfaces will be represented, as well as solids that are limited by a finite number of surfaces by means of parameterizations based on spherical coordinates and then present them in the GeoGebra 3D graphic view using the Surface command, in this way you have an unbeatable visualization, perception, manipulation and understanding of the outline of surfaces in the space in a dynamic and friendly environment. We conclude with a case of modeling application of the largest planetarium in the world applying parametric surfaces based on spherical coordinates
Keywords: Modeling. Surfaces. Parameterization. Spherical Coordinates. GeoGebra.
A Economia Doméstica e Rural Presente no Capítulo XII da Obra Rechenbuch für Deutsche Schulen in Brasillien 2º Heft, de Matheus Grimm
Authors: Britto Silvio Luiz Martins , Bayer Arno
Published: June 2020

O artigo analisa a obra Rechenbuch für Deutsche Schulen in Brasillien 2º Heft[1], de Matheus Grimm[2], com ênfase na seção XII, que aborda cálculos de economia doméstica e rural. Como o tema se insere na História da Educação Matemática, este estudo qualitativo e documental ampara-se na história cultural. A obra editada pela livraria Selbach, de Porto Alegre, teve sua primeira edição em 1900. O público-alvo eram os alunos do 3º e 4º ano elementar das escolas rurais teuto-brasileiras, unidocentes e mistas. A ideia era orientar os futuros colonos em suas receitas e despesas para administrar corretamente o orçamento familiar e gerenciar a produção na propriedade rural. Essa prática era comum nessas comunidades, pois havia o intuito de preparar as crianças para o futuro, com condições de realizar transações comerciais e dar continuidade aos negócios da família. Tais ações, contemporaneamente, fariam parte da denominada Educação Financeira, como objeto de conhecimento indispensável a ser trabalhado nas escolas brasileiras. As atividades desenvolvidas, a partir de situações-problema, estão relacionadas aos diferentes conteúdos matemáticos, envolvendo a aritmética, desenvolvendo habilidades para o manejo do cálculo escrito e mental por meio da resolução de problemas do cotidiano.
 
Palavras-chave: História da Educação Matemática. Ensino. Economia Doméstica e Rural.
 
Abstract
The article analyzes the book Calculation for German schools in Brazil 2nd notebook, by Matheus Grimm, with an emphasis on section XII, which addresses household and rural economy calculations. As the theme is inserted in the History of Mathematics Education, this qualitative and documentary study is based on cultural history. The book published by the bookstore Selbach, Porto Alegre, had its first edition in 1900. The target audience were the students of the 3rd and 4th elementary year of the rural schools in Brazil, unidocentes and mixed. The idea was to guide the future settlers in their income and expenses to properly manage the family budget and manage the production in the rural property. This practice was common in these communities, since it was intended to prepare the children for the future, able to carry out commercial transactions and give continuity to the family business. Such actions, at the same time, would be part of the denominated Financial Education, as an object of knowledge indispensable to be worked in Brazilian schools. The activities developed, based on problem situations, are related to different mathematical contents, involving arithmetic, developing skills for the management of written and mental calculation through the resolution of everyday problems.
 
Keywords: History of Mathematics Education. Teaching. Domestic and Rural Economy.
Derivadas Parciais: um Estudo com Base na Teoria APOS
Authors: Rachelli Janice , Bisognin Vanilde
Published: June 2020

Neste artigo, apresentamos os resultados de um estudo que tem como objetivo investigar as construções mentais desenvolvidas pelos estudantes de um curso de mestrado em ensino de Matemática para a compreensão do conceito de derivadas parciais, tendo a teoria APOS como referencial teórico e metodológico. Para tanto, elaboramos a decomposição genética em que foram descritas as possíveis estruturas e mecanismos mentais necessários à construção do conceito e desenvolvemos situações de ensino em sala de aula em uma disciplina que trata dos fundamentos do Cálculo, tendo o ciclo ACE como metodologia de ensino. Os resultados obtidos, por meio dos registros dos alunos e das anotações no diário de campo, indicam que os estudantes apresentam algumas dificuldades em trabalhar com problemas que requerem maior conhecimento conceitual, porém desenvolvem as construções mentais previstas na decomposição genética em atividades que possibilitam passo a passo o desenvolvimento de ações e a interiorização de processos para a encapsulação do objeto derivadas parciais, além da generalização ao tratar o esquema das derivadas parciais no contexto das equações diferenciais.
 
Palavras-chave: Teoria APOS. Decomposição Genética. Derivadas Parciais. Compreensão de Conceitos.
 
Abstract
In this article, we present the results of a study that aims to investigate the mental constructs developed by students of a master course in teaching Mathematics for understanding the concept of partial derivatives, based on the APOS theory as a theoretical and methodological reference. For that, the genetic decomposition was elaborated in which the possible mental structures and mechanisms necessary to the concept construction were described and classroom teaching situations were developed in a discipline that deals with the fundamentals of Calculus, with the ACE cycle as a teaching methodology. The results obtained through student records and field diary annotations indicate that students present some difficulties in working with problems that require greater conceptual knowledge, but they develop the mental constructions foreseen in the genetic decomposition in activities that make possible the sequence of steps, the development of actions, and the internalization of processes for the encapsulation of the partial derivative object, as well as generalization in dealing with the scheme of partial derivatives in the context of differential equations.
 
Keywords: APOS Theory. Genetic Decomposition. Partial Derivatives. Understanding Concepts.
Conhecimentos de Professores de Matemática em Início de Carreira Sobre o Campo Aditivo
Authors: Neves Almeida Rafael , Pietropaolo Ruy Cesar
Published: June 2020

Este trabalho apresenta um estudo realizado com cinco professores de Matemática, em início de carreira, ex-bolsistas do Programa Institucional de Bolsa de Iniciação à Docência (Pibid), cujo objetivo foi evidenciar os Conhecimentos Didáticos e Curriculares dos participantes sobre o ensino de problemas do campo aditivo, conforme indicado pelos parâmetros curriculares nacionais. A coleta de dados se deu por meio de entrevistas e protocolos respondidos pelos professores. Como referenciais teóricos, no tocante ao início de carreira, foram utilizados os trabalhos de Huberman e Garcia. Em relação aos conhecimentos de professores necessários à docência optou-se por Ball, Thames e Phelps. A análise dos dados nos permitiu verificar que os professores no processo de ensino do campo aditivo dão bastante ênfase à ideia de combinar dois estados para obter um terceiro, não destacando outros importantes significados. Portanto, faz-se necessário uma ampliação na base de conhecimentos desses docentes para o ensino das operações.

 

Palavras-chave: Professores em Início de Carreira. Conhecimentos Matemáticos para o Ensino. Campo Aditivo. PIBID.

 

Abstract

In this work, we will present a study carried out with five early-career teachers, former scholarship recipients of the Programa Institucional de Bolsa de Iniciação a Docência (Pibid), whose objective was to highlight the participants' Didactic and Curricular Knowledge about the notion of addition. The data collection was done through interviews and protocols answered by the teachers. As theoretical references, regarding the beginning of the career, the works of Huberman (1995) and Garcia (1999) were used. Regarding the teachers' knowledge required for teaching, Ball, Thames and Phelps (2008) were chosen. The analysis of the data allowed us to verify that the teachers' knowledge about addition operation is restricted to the meaning of joining and that the idea most used to work with this theme in the classroom involves problem situations with money. Therefore, it is necessary to increase the knowledge base of these teachers.

 

Keywords: Teacher Early-Career Teachers. Mathematical Knowledge for Teaching (MKT).
Antecipação e Encaminhamento de uma Atividade de Modelagem Matemática no Contexto de Aulas de Educação Financeira
Authors: Da Silva Ariel Cardoso , Seki Jeferson Takeo Padoan , Pessoa da Silva Karina Alessandra
Published: June 2020

Neste artigo apresentamos resultados de uma pesquisa em que consideramos a antecipação uma etapa inerente ao desenvolvimento de uma atividade de modelagem matemática e que pode auxiliar o professor a prever um encaminhamento em sala de aula. Para isso, desenvolvemos uma atividade de modelagem matemática, com o tema ‘orçamento familiar’, em duas disciplinas de um curso de Licenciatura em Matemática: matemática financeira e tecnologias em Educação Matemática. Fundamentados nos pressupostos teóricos da modelagem matemática como alternativa pedagógica e considerando uma pesquisa de abordagem qualitativa, analisamos os registros escritos e a transcrição dos áudios gravados no desenvolvimento da atividade, de forma descritiva e interpretativa. A análise nos possibilitou inferir que as relações que se estabelecem entre a antecipação e a prática com atividades de modelagem matemática, são dinâmicas e ocorrem a partir das reflexões do professor a respeito de suas intenções e das possíveis resoluções dos alunos, bem como pode sofrer (re)planejamentos.
 
Palavras-chave: Educação Matemática. Educação Financeira. Modelagem Matemática.
 
Abstract
In this paper we present results of a research in which we consider the anticipation an inherent step in the development of a mathematical modeling activity and that can help the teacher to predict a routing in the classroom. For this, we developed a mathematical modeling activity, with the theme 'family budget', in two disciplines of a course of Mathematics Degree: financial mathematics and technologies in Mathematics Education. Based on the theoretical assumptions of mathematical modeling as a pedagogical alternative and considering a qualitative approach, we analyze the written records and the transcription of recorded audio in the development of the activity, in a descriptive and interpretative way. The analysis allowed us to infer that the relationships established between anticipation and practice with mathematical modeling activities are dynamic and occur from the teacher's reflections about their intentions and possible student resolutions, as well as being able to suffer ( re)planning.
 
Palavras-chave: Mathematics Education. Financial Education. Mathematical Modeling.