Analysing the Suitability of C16/20-X0v(H)-24-F3 Concrete for Pumping

2015 ◽  
Vol 812 ◽  
pp. 213-218
Author(s):  
Alexandra Kitti Németh ◽  
M.B. Maros

The current paper introduces a case study dealing with the problem of pumpability of the ready-mix concrete of grade of C16/20-X0v (H)-24-F3 []. During solving a practical industrial problem we have worked out a modified composition of the related concrete material in order to improve the pumpability. After describing some possible theoretical and practical methods the authors give suggestion for a practical solution. The characteristic feature of the method consists in modifying the recipe of the given grade of concrete without altering the additive structure, and to assure the pulp saturation. The paper reports the results of standardised physical and mechanical tests, executed on the novel concrete material. Based on these results it has been proved, that besides solving the original practical problem of pumpability, the new concrete material possesses better application and technological performance, and is more economical to produce.

2018 ◽  
Vol 149 ◽  
pp. 01071
Author(s):  
Dorra Ellouze ◽  
Aida Ghammouri ◽  
Rahma Ben Amar

Ready-mix concrete (RMC) in Tunisia is becoming more and more in demand in the civil engineering sector thanks to its qualities of handling in the fresh state and resistance in the hardened state, this composite material must respect the quality-price ratio. A RMC with a minimal cost is the object of our work. This research is part of the opening of higher education on professional life, where we optimized the formulation of a RMC. This work has 3 axes. In the first place the resources in building materials were characterized, namely various samples of sand, gravel, cement and water. Subsequently, the adjuvant-cement ratio (A/C) was optimized. Finally, the workability of the concrete as well as its mechanical aptitude at various ages 7, 14 and 28 days were characterized. These examinations have resulted in an appropriate formulation for any type of resource that varies according to the provenance of the quarries (gravel and sand), the effect of the plasticizer-water reducer is found for a very interesting A/C ratio, the mechanical tests for different ages are also conclusive.


2017 ◽  
Vol 9 (1) ◽  
pp. 105-128 ◽  
Author(s):  
François Bry ◽  
Alexander Yong-Su Pohl

Purpose Several challenges of today’s higher education were motivations to reconsider the contents and formats of lectures and tutorials and to conceive the classroom communication system Backstage, a social media platform supporting a novel form of large-class teaching. The purpose of this paper is to report on the challenges met, on the novel teaching form and on an evaluation of this teaching form. Design/methodology/approach The use of Backstage in two courses is evaluated. One of the courses has been specially adapted to promote student participation, the other course has been held in a traditional way. To investigate the usefulness and acceptance of Backstage in the given settings the data collected on Backstage and student responses in surveys are analyzed. Findings The results indicate that Backstage can foster interactivity and awareness in large-class lectures when used in combination with a teaching format that provides opportunities for and encourges lecture-relevant communication. Furthermore, students appreciated the use of Backstage. Research limitations/implications This paper reports on a case study which lacks generalizability. Further studies under controlled conditions and of the learning effectiveness of the approach are still outstanding. Practical implications This paper describes an approach fostering a form of Active Learning in large classes. Since large classes are widespread in higher education, the approach has a considerable practical potential. Social implications The paper describes an approach to large class higher education teaching in using social media. Originality/value Similar results have not been published so far.


TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.


2015 ◽  
Vol 60 (1) ◽  
pp. 81-102
Author(s):  
KErstin Thomas

Kerstin Thomas revaluates the famous dispute between Martin Heidegger, Meyer Schapiro, and Jacques Derrida, concerning a painting of shoes by Vincent Van Gogh. The starting point for this dispute was the description and analysis of things and artworks developed in his essay, “The Origin of the Work of Art”. In discussing Heidegger’s account, the art historian Meyer Schapiro’s main point of critique concerned Heidegger’s claim that the artwork reveals the truth of equipment in depicting shoes of a peasant woman and thereby showing her world. Schapiro sees a striking paradox in Heidegger’s claim for truth, based on a specific object in a specific artwork while at the same time following a rather metaphysical idea of the artwork. Kerstin Thomas proposes an interpretation, which exceeds the common confrontation of philosophy versus art history by focussing on the respective notion of facticity at stake in the theoretical accounts of both thinkers. Schapiro accuses Heidegger of a lack of concreteness, which he sees as the basis for every truth claim on objects. Thomas understands Schapiro’s objections as motivated by this demand for a facticity, which not only includes the work of art, but also investigator in his concrete historical perspective. Truth claims under such conditions of facticity are always relative to historical knowledge, and open to critical intervention and therefore necessarily contingent. Following Thomas, Schapiro’s critique shows that despite his intention of giving the work of art back its autonomy, Heidegger could be accused of achieving quite the opposite: through the abstraction of the concrete, the factual, and the given to the type, he actually sets the self and the realm of knowledge of the creator as absolute and not the object of his knowledge. Instead, she argues for a revaluation of Schapiro’s position with recognition of the arbitrariness of the artwork, by introducing the notion of factuality as formulated by Quentin Meillassoux. Understood as exchange between artist and object in its concrete material quality as well as with the beholder, the truth of painting could only be shown as radically contingent. Thomas argues that the critical intervention of Derrida who discusses both positions anew is exactly motivated by a recognition of the contingent character of object, artwork and interpretation. His deconstructive analysis can be understood as recognition of the dynamic character of things and hence this could be shown with Meillassoux to be exactly its character of facticity – or factuality.


2002 ◽  
Vol 19 (4) ◽  
pp. 23-41
Author(s):  
Safoi Babana-Hampton

The essay examines the texts of the two women writers - Leila Abouzeid (from Morocco) and Nawal El Saadawi (from Egypt) - as offering two female perspectives within what is commonly referred to as "feminine" writing in the Arab Muslim world. My main interest is to explore the various discursive articulations of female identity that are challenged or foregrounded as a positive model. The essay points to the serious pitfalls of some feminist narratives in Arab-Muslim societies by dealing with a related problem: the author's setting up of convenient conceptual dichotomies, which account for the female experience, that reduce male-female relationships in the given social context to a fundamentally antagonistic one. Abouzeid's novel will be a case study of a more positive but also realistic and complex perspec­tive on female experience ...


Geoheritage ◽  
2021 ◽  
Vol 13 (2) ◽  
Author(s):  
M. Pásková ◽  
J. Zelenka ◽  
T. Ogasawara ◽  
B. Zavala ◽  
I. Astete

AbstractHolistic interpretation of Earth heritage is one of the most important tasks of UNESCO Global geoparks. The ABC (abiotic, biotic, and cultural interconnections) concept is a potential interpretive approach used in Earth heritage popularization through geotourism. Apart of the deeper understanding of this concept, this study explores the application of this concept in selected geoparks. The Colca and Volcanoes Andagua UNESCO Global Geopark (Peru) and Muroto UNESCO Global Geopark (Japan) served as a case study in the frame of this qualitative research conducted during the summer 2019. Results show that the ABC approach is nearly perfectly understood by both geoparks, however there are both internal and external factors which influence the extent and form of how this concept is applied in practice. Except for specific geographical settings, different stages of geopark product development, and different managerial approaches, they mainly include the level of scientific knowledge and general education in the given geopark, as well as level of knowledge management and networking with another UNESCO global geoparks. The more experienced Muroto Geopark interpretation exhibits a comparatively higher level of visible ABC application, while the Colca and Volcanoes Andagua Geopark can benefit in the future from the natural inclination and ability of the local people to integrate the cultural aspects into their Earth heritage interpretation.


2020 ◽  
Vol 73 (3) ◽  
pp. 497-520
Author(s):  
Nicola Pozza

AbstractNumerous studies have dealt with the process of globalization and its various cultural products. Three such cultural products illustrate this process: Vikas Swarup’s novel Q and A (2005), the TV quiz show Kaun banega crorepati? (Who Wants to Be a Millionaire?), and Danny Boyle’s film Slumdog Millionaire (2008). The novel, the TV show and the film have so far been studied separately. Juxtaposing and comparing Q and A, Kaun banega crorepati, and Slumdog Millionaire provides an effective means to shed light on the dialogic and interactive nature of the process of globalization. It is argued through this case study that an analysis of their place of production, language and content, helps clarify the derivative concepts of “glocalization” and “grobalization” with regard to the way(s) contemporary cultural products respond to globalization.


2020 ◽  
Vol 35 (9) ◽  
pp. 2675-2679 ◽  
Author(s):  
Katharine Lawrence ◽  
Kathleen Hanley ◽  
Jennifer Adams ◽  
Daniel J Sartori ◽  
Richard Greene ◽  
...  

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Sindolfo Miranda Filho ◽  
Julio Melo ◽  
Luiz Eduardo Leite ◽  
Guido Lemos

Context-aware systems are able to monitor and automatically adapt their operation accordingly to the execution context in which they are introduced. Component-based software engineering (CBSE) focuses on the development and reuse of self-contained software assets in order to achieve better productivity and quality. In order to store and retrieve components, CBSE employs component repository systems to provide components to the system developers. This paper presents an active component repository that is able to receive the current configuration from the context-aware system and compute the components and the new architecture that better fit the given context. Since the repository has a wide knowledge of available components, it can better decide which configuration is more suitable to the running system. The repository applies Fuzzy logic algorithm to evaluate the adequacy level of the components and GRASP algorithm to mount the new system architecture. In order to verify the feasibility of our approach, we use a digital TV middleware case study to achieve experimental results.


2008 ◽  
Vol 72 (1) ◽  
pp. 515-519 ◽  
Author(s):  
E. Valsami-Jones ◽  
D. Berhanu ◽  
A. Dybowska ◽  
S. Misra ◽  
A. R. Boccaccini ◽  
...  

AbstractIn recent years it has become apparent that the novel properties of nanomaterials may predispose them to a hitherto unknown potential for toxicity. A number of recent toxicological studies of nanomaterials exist, but these appear to be fragmented and often contradictory. Such discrepancies may be, at least in part, due to poor description of the nanomaterial or incomplete characterization, including failure to recognise impurities, surface modifications or other important physicochemical aspects of the nanomaterial. Herew em ake a casef or the importance of good quality, well-characterized nanomaterials for future toxicological studies, combined with reliable synthesis protocols, and we present our efforts to generate such materials. The model system for which we present results is TiO2 nanoparticles, currently used in a variety of commercial products.


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