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Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 506
Author(s):  
Martin Hirman ◽  
Jiri Navratil ◽  
Michaela Radouchova ◽  
Jiri Stulik ◽  
Radek Soukup

This article addresses reliability under the sweat of interconnection techniques for the mounting surface mounted device (SMD) components and fully printed humidity sensors onto conductive stretchable textile ribbons. Samples underwent testing for the effect of ageing by artificial sweat on their electrical resistance using both alkaline and acidic artificial sweat. The best results in terms of electrical resistance change were obtained for samples soldered to the conductive fibers interwoven in the ribbon. However, this method can damage the ribbon due to the high temperature during soldering and significantly reduce the mechanical properties and flexibility of the ribbon, which can lead to a limited service life of samples. On the other hand, adhesive bonding is a very interesting alternative, where the above-mentioned properties are preserved, but there is a significant effect of sweat ageing on electrical resistance. The results of fully printed graphene-based humidity sensors show that, for the intended use of these sensors (i.e., detection of changes in moisture on the human body), usage of the samples is possible, and the samples are sufficiently reliable in the case of sweat degradation. In addition, the response of the sensor to humidity is quite high: 98% at a relative humidity of 98%.


Diagnostics ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 104
Author(s):  
Dorian Petonnet ◽  
Stéphane Marot ◽  
Isabelle Leroy ◽  
Julien Cohier ◽  
Charline Ramahefasolo ◽  
...  

SARS-CoV-2 viral antigen detection may be an interesting alternative to RT-PCR for the diagnosis of SARS-CoV-2 infection as a less laborious or expensive method but requires validation. This study aimed to compare the performance of the DiaSorin™ LiaisonXL automated quantitative antigen test (QAT) and the AAZ™ rapid antigen test (RAT) to the DiaSorin™ MDX RT-PCR assay. A total of 242 nasopharyngeal samples were tested at La Pitié-Salpêtrière University Hospital (Paris, France). Performances for the detection of variants of SARS-CoV-2 were further investigated. RATs were visually read for qualitative results and band intensity was determined. Overall sensitivity was 63.2% for QAT and 58.6% for RAT. For RT-PCR Ct value 25, sensitivity was 89.8% for both tests. Both tests showed comparable sensitivity for detection of variants. There was a strong relationship between antigen concentration and band positivity. On the same set of samples these tests share similar performances.


Author(s):  
Fernanda Rodrigues Santos Valle ◽  
Paulo Cesar Gonçalves ◽  
Maria Gabriela A. Ranieri ◽  
Mirian de Lourdes Noronha Motta Melo ◽  
Valquíria Claret dos Santos

abstract: The utilization of wastes from demolition in civil construction in self compacting concrete (SCM) has the potential to reduce both the environmental impact and financial cost. In this context, this article aims to verify the behavior of the incorporation of recycled aggregates of civil construction in the mix designs of self-compacting mortar (SCM) in replacing cement, presenting as an interesting alternative to natural raw materials. This study used the EMMA® software to optimize the choice of percentages of fine recycled aggregates when replacing cement. The proportions chosen were 0%, 5%, 15%, and 25%, through the analysis of the granular packing curve of the respective mix designs. The proportion of 0% has in its composition cement, metakaolin, sand, superplasticizer (SP) and water. The parameters obtained, through tests in the fresh state of the mini-slump and mini-funnel V, certified the samples as SCM. The compressive strength and flexural tensile strength tests in the hardened state demonstrated a reduction in mechanical properties of the material with cement replacement. It is concluded that the waste used brick and ceramic can be added in replacement to the cement in SCM without significant loss of properties in the fresh and hardened state.


2022 ◽  
Vol 58 (1) ◽  
Author(s):  
A. Tichai ◽  
P. Arthuis ◽  
H. Hergert ◽  
T. Duguet

AbstractThe goal of the present paper is twofold. First, a novel expansion many-body method applicable to superfluid open-shell nuclei, the so-called Bogoliubov in-medium similarity renormalization group (BIMSRG) theory, is formulated. This generalization of standard single-reference IMSRG theory for closed-shell systems parallels the recent extensions of coupled cluster, self-consistent Green’s function or many-body perturbation theory. Within the realm of IMSRG theories, BIMSRG provides an interesting alternative to the already existing multi-reference IMSRG (MR-IMSRG) method applicable to open-shell nuclei. The algebraic equations for low-order approximations, i.e., BIMSRG(1) and BIMSRG(2), can be derived manually without much difficulty. However, such a methodology becomes already impractical and error prone for the derivation of the BIMSRG(3) equations, which are eventually needed to reach high accuracy. Based on a diagrammatic formulation of BIMSRG theory, the second objective of the present paper is thus to describe the third version (v3.0) of the code that automatically (1) generates all valid BIMSRG(n) diagrams and (2) evaluates their algebraic expressions in a matter of seconds. This is achieved in such a way that equations can easily be retrieved for both the flow equation and the Magnus expansion formulations of BIMSRG. Expanding on this work, the first future objective is to numerically implement BIMSRG(2) (eventually BIMSRG(3)) equations and perform ab initio calculations of mid-mass open-shell nuclei.


2021 ◽  
Vol 15 (58) ◽  
pp. 100-121
Author(s):  
Marlize Reffatti Zinelli Viezzer ◽  
Odorico Konrad ◽  
Bruno Furquim Horodenski ◽  
Aparecida Garcia Pacheco Gabriel ◽  
Rodrigo Spinelli

Resumo: A discussão sobre edificações sustentáveis vem sendo abordada há décadas por diferentes autores, em geral com foco no consumo energético e na vida útil dos materiais, contudo para atender esses objetivos são necessárias novas tecnologias que promovam mais sustentabilidade. Para tanto, a inclusão de fibras vegetais em compostos de solo-cimento se mostram uma alternativa interessante, e pelo fato do setor industrial madeireiro movimentar a economia local no município de Alta Floresta o resíduo serragem passa a ser um possível agregado nos tijolos ecológicos, uma vez que o armazenamento inadequado deste resíduo pode causar sérios impactos ambientais, portanto, este estudo se propôs a desenvolver um tijolo ecológico fabricado a partir da mistura de solo-cimento e serragem de três espécies florestais da Amazônia, Cambará - Vochysia sp., Cedrinho - Erisma uncinatum Warm., Garapeira. - Apuleia sp, e ainda avaliar a resistência a compressão com intervalos de cura de 7, 14, 21 e 28 dias, com o intuito de verificar a viabilidade do material construtivo. Para a realização do experimento, os tijolos foram fabricados com traço de 1:8:2,5, (cimento: solo: serragem) e a serragem utilizada com dois tratamentos, in natura e tratada por imersão e padronização granulométrica. O material misturado foi compactado em uma prensa hidráulica. Como resultado, os tijolos com serragem apresentaram valores de resistência mecânica de: Cedrinho 1,26Mpa, Cambará 1,70Mpa e Garapeira 1,95Mpa e teores de absorção de umidade  de 15,7%, 17,6% e 13,8%, respectivamente.Palavras-chave: Sustentabilidade. Tijolo solo-cimento. Serragem. Abstract: The discussion about sustainable edifications has been addressed in decades by different authors, generally focusing energetic consume and the materials lifespan, however to reach these goals it is necessary new technologies that promote more sustainability. For that the inclusion of vegetal fibers in soil-cements composts present as an interesting alternative, and because the timber industry moves the local economy in the city of Alta Floresta the sawdust residue become a possible aggregate of ecologic bricks since inadequate storage of this material can cause serious environment impacts, therefore this study propose to develop an ecologic brick manufactured by the mix of soil-cement and sawdust of three Amazonian species: Cambará - Vochysia sp., Cedrinho - Erisma uncinatum Warm, Garapeira. - Apuleia sp., and also evaluate the compression resistance in 7, 14, 21, 28 days intervals, aiming to verify the feasibility of the constructive material. To carry out the experiment the bricks were manufacture with the ratio of 1:8:2,5 (cement: soil: sawdust), and the sawdust used was treated twice, in natura, treated by immersion and granulometric standardization. The mixed material was compacted in a hydraulic press. As a result, the sawdust bricks showed resistance values of: Cedrinho 1.26 MPa, Cambará 1.70 MPa and Garapeira 1.95 MPa and humidity absorption percentage of 15.7%, 17.6%, and 13.8% % respectively.Keywords: Sustainably, Ecologic Brick, Sawdust


2021 ◽  
Author(s):  
Sérgio Baldo Junior ◽  
Thiago Faria dos Santos ◽  
Renato Tinós ◽  
Paulo Roberto Pereira Santiago

Abstract The analysis of running patterns, especially those associated with fatigue, can help specialists in designing more efficient workouts and preventing injuries in high-performance sports. However, classifying running patterns is not trivial for humans. An interesting alternative is to use Machine Learning methods, such as Artificial Neural Networks (ANNs), to classify running patterns. In this work, ground reaction forces are measured by sensors coupled to the base of a low-cost open-source treadmill. ANNs are used to classify the force signals and to indicate the occurrence of fatigue. Different features, extracted from the force signals, are proposed and investigated. A Genetic Algorithm (GA) is used to select the best features. The experimental results indicate that the ANN is able to classify the running patterns with good accuracy. In addition, some features selected by the GA provide important information regarding the identification of fatigue in treadmill running.


2021 ◽  
Vol 11 (24) ◽  
pp. 11980
Author(s):  
Simon Duque Tisnes ◽  
Atif Tasneem ◽  
Laurent Petit ◽  
Christine Prelle

Micro-factories are characterized by high modularity, reconfigurability and mobility. To achieve this, the micro-factory needs a conveyor which is able to transport objects in as many degrees of freedom (DoF) as possible, executes optimal trajectories of these objects in terms of energy and precision and is robust to withstand possible malfunctions. In this article, we present the planar conveyance of objects on a digital actuation array following trajectories generated by an adapted A* algorithm. The A* algorithm exploits the predictions of a developed dynamic model of the system to find the optimal paths (in terms of energy) on the conveyor surface. The dynamic model predictions were compared to experimental measurements, obtaining low root-mean-square-errors for all conditions. Uni-dimensional conveyance tests characterized the influence of the control parameters. Then, bi-dimensional motions characterized the conveyor’s performance. From the bi-dimensional test, a position root-mean-square-error of 20 μm was measured for a 1109 μm open-loop controlled trajectory. The modular nature of the array allows easy scaling and avoiding possible malfunctioning zones, increasing the robustness of the micro-conveyor. The experimental tests demonstrate that the proposed device is an interesting alternative for the micro-factory.


2021 ◽  
Vol 1 (2) ◽  
pp. 116-143
Author(s):  
Basheer Hussein Motawe Altarturi ◽  
Mousa Abdul Karim Ajouz

Islamic banking is a multidisciplinary field that integrates banking and fiqh muamalat using mathematical, statistical, computational, and economic models. Islamic banking is dependent on the development of Islamic financial transactions for its growth. Islamic banking applications in are emerging not only as means of enhancing financial results but also as means of enhancing the sustainability and productivity of the economy. This paper aims to conduct a comprehensive systematic bibliometric analysis of Islamic banking literature. It starts by finding 3,285 documents published in the Scopus database from January 1983 to October 2021. This paper, using bibliometric analysis, describes the most significant literature, denotes the related discipline fields, and offers insight into the existing research patterns and possible future trends in Islamic banking. The financial crisis has revolutionised Islamic banking as an interesting alternative to the fragile current banking system. The findings establish a solid grounding for future research in the field of Islamic banking.


Knowledge ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 75-82
Author(s):  
Victor Perez-Puyana ◽  
Mercedes Jiménez-Rosado ◽  
Alberto Romero

Virtual tools are frequently used in education. Among them, the use of virtual laboratories could be an interesting alternative to strengthen the practical concepts of the students, especially in the current paradigm in which the presence of students is often not possible. For this reason, the aim of this study was to analyse the use of different digital tools for the improvement of the teaching process during the COVID-19 pandemic period. To this end, a comparison of the application of different digital alternatives was carried out, evaluating the differences found with previous teaching courses. The results indicate that, although students welcome these activities, they cannot replace face-to-face practices, being considered as a complementary activity.


Author(s):  
Francisco Cabrera ◽  
Álvaro Torres-Aravena ◽  
Fernanda Pinto-Ibieta ◽  
José Luis Campos ◽  
David Jeison

Production of polyhydroxyalkanoates (PHA) has generated great interest as building blocks for bioplastic production. Their production using mixed microbial cultures represents an interesting alternative, since it enables the use of organic wastes as a carbon source. Feast/famine strategy is a common way to promote selection of microorganisms with PHA accumulation capacity. However, when using waste sources, changes in substrate concentration are expected, that may affect performance and efficiency of the process. This study showed how the dissolved oxygen level can be used for online control of the cycle time, ensuring that the desired feast/famine ratio is effectively applied. An operation strategy is presented and validated, using sequential batch reactors fed with acetate as the carbon source. Production of polyhydroxybutyrate (PHB) was studied, which is the expected type of PHA to be synthetized when using acetate as substrate. Two reactors were operated by applying the proposed control strategy, to provide F/F ratios of 0.2 and 0.6, respectively. A third reactor was operated with a fixed cycle time, for comparison purposes. Results showed that the reactor that operated at an F/F ratio of 0.6 promoted higher biomass productivity and PHB content, as a result of a better use of available time, preventing unnecessary long famine times. The application of the tested strategy is a simple a reliable way to promote a better performance of feast/famine-based bioreactors involving mixed microbial cultures for PHB production.


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