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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Footwear sustainability: brazilian panorama, materials and contribution of sole material
No full textO Brasil é o quarto maior produtor de calçados do mundo, exporta parte da produção, porém o valor mais expressivo em volume de vendas é no mercado nacional. A concorrência internacional, sobretudo com a China, fez com que o país buscasse a redução de custo em mão de obra. A gestão de resíduos sólidos no Brasil, foi regulamentada, porém poucas ações estão sendo feitas na prática. Mesmo assim, há casos de empresas calçadistas brasileiras adotando medidas na gestão de resíduos, no viés proativo, por meio da minimização de resíduos, a partir do design (impressão 3D) e da substituição de materiais (insumos químicos atóxicos, tingimento natural, biopolímero); no viés reativo, por reuso (resíduos do processo), reciclagem (componentes poliméricos), geração de energia (coprocessamento) e descarte (tratamento de efluentes). Esta pesquisa teve como objetivo estudar as ações sustentáveis das empresas brasileiras de componentes de calçados; verificar o que compõe o selo nacional Origem Sustentável e sua contribuição para o setor; e, também, realizar uma formulação de solado de PVC com inserção de serragem de bambu e avaliar suas propriedades mecânicas, FTIR, MEV, DSC e TGA. Os resultados das entrevistas com as empresas mostraram que em algumas delas são empregadas matérias primas recicladas; e que os fabricantes entrevistados de laminado e solado de PVC têm baixa emissão de resíduos e efluentes; um outro, produz componente de calçado com 50% de resíduos de tecidos e laminados vindos dos clientes. Além disso, o selo Origem Sustentável propiciou economia em insumos e no descarte, e dá suporte às empresas a exportarem e controlarem as substâncias restritas. O desenvolvimento do compósito obteve boa dispersão da serragem de bambu, porém houve a diminuição do desempenho das propriedades mecânicas em todas as amostras, em relação ao PVC puro. Por fim, corroborando com a literatura, constatou-se que há poucas soluções concretas no Brasil, referentes à circularidade dos produtos. Com base nestas considerações, sugere-se pesquisas futuras em logística reversa, biopolímeros, reciclabilidade de calçados e soluções em designBrazil is the fourth largest producer of shoes in the world, exports part of the production, however the most expressive value in sales volume is in the national market. International competition market, especially with China, has made the country seek to reduce labor costs. The management of solid waste in Brazil has been regulated, but few actions are taken in practice. Even so, there are cases of Brazilian footwear companies adopting actions in the management of residues, in a proactive bias, through the minimization of residues, from the design (3D printing) and the substitution of materials (non-toxic chemical inputs, natural dyeing, biopolymer); in the reactive bias, through reuse (waste from the process), recycling (polymeric components), energy generation (coprocessing) and disposal (effluent treatment). This research aimed to study the sustainable actions of Brazilian footwear companies of components; verify the national seal Sustainable Origin composition and its contribution to the sector; and, also, carry out a PVC sole formulation with bamboo sawdust and evaluate its mechanical, FTIR, MEV, DSC and TGA properties. The results of the companys interviews showed that some of them have used recycled raw materials; manufacturers interviewed from PVC laminate and sole generate low waste and effluent emissions; another, a footwear component company applied 50% of fabric and laminate wastes from customers. In addition, the Sustainable Origin seal provided savings in inputs and disposal and supports companies to export and control restricted substances. The development of the composite obtained good dispersion of the bamboo sawdust, but there was a performance decrease of mechanical properties in all samples, in relation to pure PVC. Finally, corroborating with the literature, it was found that there are few concrete solutions in Brazil, regarding the circularity of products. Based on these considerations, future research on reverse logistics, biopolymers, footwear recyclability and design solutions are suggeste
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Painéis de compósitos cimentícios com reforço têxtil 3D e multiescala em fibra vegetal
No full textTextile structures present advantages to strengthen cementitious composites, which depend on the type of fiber, that are organized in bundle fiber or twisted yarn, and ligament design. In fabric-cement composites, the limited impregnation of cementitious matrix products due to thick and twisted yarns leads to premature failure due to poor bonding strength and interaction. A textile impregnated by partially biobased green-epoxy resin coating demonstrates a more cohesive behavior, ensuring even stress distribution throughout the yarns. To guarantee the mechanical properties of composite, good adhesion between textile-matrix is necessary, besides avoiding fiber degradation. The use of hybrid braids can reduce costs and increase efficiency. This study assessed how two commercial jute textiles and 2D or 3D sisal/PET hybrid braided textiles, separately, affect the interactions by reinforcement of cementitious composites, these interactions were assessed according to mechanical behavior (four-point bending, tensile stress, and physical fabric characteristics), bonding and interfacial transition zone (pullout test, flexural stress specific deformation behavior, scanning electron microscopy - SEM), and visual and chemical compounds analysis (X-ray diffraction - XRD, Fourier Transform Infrared Spectroscopy, energy-dispersive X-ray spectrometer - EDS). The open weave jute fabric exhibited inferior mechanical properties (tensile behavior - 175 N and mass per area 192 g/m²). However, its larger interstices in the weave structure played a superior interaction with the matrix in composite boards, and micro silica coating displayed an enhanced ultimate strength modulus of rupture (6.81 MPa), and the highest specific energy (4.28 ± 0.91) kJ/m². The calcium-silicate-hydrate products are responsible for strong chemical adhesions between the phases of the composite. Among developed sisal/PET braided textiles, due to green epoxy resin being stiffer, comparing sisal/PET yarn before and after coating, the youngs modulus doubled its value (from 2.12 ± 0.32 to 4.11 ± 0.36 N/Tex). Sisal/PET yarn presented in the pullout test of yarn-mortar the pseudo-ductile behavior and high energy absorption, the peak load (371.26 N), and toughness until peak loading (2110.00 N.mm). Composites reinforced by multidimensions textiles exhibited 3D fabric superior values than 2D textiles in four-point bending tests for modulus of rupture (7.45±0.48 MPa) and specific energy (5.72±0.31 kJ/m²). Finally, textile treatments, inorganic powder coatings, and resin coating on textile are necessary for its application to ensure even stress distribution throughout the yarns into interface transition between textile-cementitious, and enhanced tensile strain capacity of composites.As estruturas têxteis apresentam vantagens para fortalecer compósitos cimentícios, as quais dependem do tipo de fibra, organizadas em feixes ou fios torcidos e do design dos ligamentos. Nos compósitos de têxteis-cimento, há a impregnação limitada da matriz cimentícia devido aos fios grossos e torcidos, o que leva a uma falha prematura devido à baixa resistência de ligação e interação. Um tecido impregnado por recobrimento de resina epóxi demonstra um comportamento mais coeso, garantindo uma distribuição uniforme do estresse ao longo dos fios. Para garantir as propriedades mecânicas do compósito, é necessária uma boa aderência entre o material têxtil e a matriz, além de evitar a degradação da fibra. O uso de entrançados híbridos pode reduzir custos e aumentar a eficiência. Este estudo avaliou como dois tecidos comerciais de juta e têxteis híbridos de sisal/PET, entrançados em 2D ou 3D, afetam as interações por reforço de compósitos cimentícios. Essas interações foram avaliadas de acordo com o comportamento mecânico (ensaio de flexão em quatro pontos, tensão de tração e características físicas do tecido), aderência e zona de transição interfacial (ensaio de pullout, comportamento específico de deformação em flexão, microscopia eletrônica de varredura - MEV) e análise visual e química dos compostos (difração de raios-X - DRX, Espectroscopia de Infravermelho com Transformada de Fourier, espectrômetro de raios-X por dispersão de energia - EDS). O tecido de juta de trama aberta apresentou propriedades mecânicas inferiores (tração - 175 N e massa por área de 192 g/m²), no entanto, seus maiores interstícios da trama proporcionaram interação superior com a matriz, e o recobrimento de micro sílica exibiu um aumento na resistência máxima do módulo de ruptura (6,81 MPa) e energia específica (4,28 ± 0,91) kJ/m². Os produtos de hidrato de silicato de cálcio são responsáveis por fortes adesões químicas entre as fases do compósito. Entre os entrançados de sisal/PET desenvolvidos, como a resina epóxi verde é mais rígida, comparando após o revestimento e antes, o módulo de elasticidade dobrou seu valor (de 2,12 ± 0,32 para 4,11 ± 0,36 N/Tex). O fio de sisal/PET apresentou no ensaio de pullout (fio-argamassa) um comportamento pseudo-dúctil e alta absorção de energia, carga máxima (371,26 N) e tenacidade na carga máxima (2110,00 N.mm). Os compósitos reforçados por têxteis multidimensional apresentaram valores superiores para o tecido 3D em relação ao 2D na flexão em quatro pontos para módulo de ruptura (7,45 ± 0,48 MPa) e energia específica (5,72 ± 0,31 kJ/m²). Por fim, os tratamentos, revestimentos por resina e pós inorgânicos garantiram a distribuição uniforme das tensões ao longo dos fios, na interface de transição têxtil-cimento e maior capacidade de deformação dos compósitos
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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