1,720,955 research outputs found
Heat sealing and convertibility of coated paper materials in vertical form fill and seal machine
Get PDFChallenges regarding the heat sealing and convertibility of coated papers in vertical form, fill, and seal (VFFS) machines were investigated. This research focused on enhancing the use of coated papers in VFFS packaging machines by identifying the optimal sealing parameters to ensure package tightness, evaluating friction-related issues to improve runnability, and developing a novel forming shoulder design to optimise material formability and minimise oil and grease properties damage during the conversion process.
To understand the performance of various coated papers in VFFS machine, PE-coated and dispersion-coated papers were tested and compared with conventional thermoplastic films. The seal properties and integrity were examined using seal strength and leak tightness measurements. Additionally, the frictional properties of the coated papers were investigated on different surfaces to identify the appropriate surface for paper runnability. The seal structure and surface characteristics of the converted packages were analysed using SEM and 3D profilometry. Finally, oil and grease measurements were performed to evaluate the impact of wrinkles on converted pouches.
The results indicated that achieving an airtight seal with coated papers requires precise control of the sealing process parameters, with serrated seal bars significantly improving the seal integrity by creating localised shear stress that enhances polymer chain entanglement. Frictional analysis revealed that the coefficient of friction was a critical factor affecting the runnability of the material in VFFS machines. The Teflon-coated forming tube and pattern-rolled 5WL stainless-steel surfaces effectively reduced friction and improved material flow over the novel forming shoulder. The new shoulder design features an optimised bending curve and other geometrical parameters that successfully minimise wrinkles and tears on the coated paper packages after the conversion process.
Through precise control of sealing parameters and advancements in tooling design, this study offers the ability to use sustainable materials in VFFS packaging. The proposed modifications to VFFS processes enhance the practicality of adopting environmentally friendly packaging solutions in the food industry and other fields.ei tietoa saavutettavuudest
Evaluation and optimization of a vertical form, fill and seal production machine for flexible packaging papers
Get PDFVertical form fill seal machines are commonly used in packaging industries to produce pillow and block bottom bags for dried products. This research evaluated and optimized the machine for fiber-based materials and compared the runnability with thermoplastic material using three different sealing tool profiles with 140 mm width forming shoulder. There are three main heat sealing parameters, sealing temperature, dwell time and sealing pressure. Each of these parameters can influence the seal quality significantly to achieve satisfactory seal strength, airtightness and adhesive bond. The initial task investigated and developed the heat sealing processing window between the seal strength and sealing parameters (sealing temperature and dwell time) using contour plots and 3D mapping relationships. The peel strength test was conducted using T-peel method with 90° pulling direction at constant rate of 300 mm/min with Shimadzu AGS-1kNX. The test samples were prepared as per the ASTM F88 guidelines. Three major failure modes were observed from the peel test. At low temperatures, about 100 °C, most of the materials experienced easy peel because the seal strength is lower than the strength of the adhesive layer. At higher temperature, above 110 °C, the molecules forms interdiffusion of chains leading to delamination and separation of seal from the sealing layer or in worst case, the material gets teared at the edge of the seal. Detailed analysis with each materials and corresponding sealing tool is thoroughly explained in the report. After the production of pillow bags, major wrinkles were observed on the surface of the bags due to sharp bending angle and fillet edge of the forming shoulders. 3D profilometer, Keyence VR 3200, was used to examine the surface roughness. The roughness value tripled on average with Fiber 85 and quadrupled with Fiber 120 because the Fiber 85 has lower stiffness and more flexibility than Fiber 120. Several suggested improvements and suggestions for future tests are further discussed
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
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
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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