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Information technology (IT) systems are known to promote improvements in quality and productivity of the work environments of complex and adaptive socio-technical systems that span hardware, community and software aspects. Systems development lies in eliciting and specifying requirements. However, current requirements of elicitation techniques are limited to correctly understanding the complexity involved in socio-technical systems. Therefore, approaches based on Resilience Engineering can provide concepts and methods for a better understanding of socio-technical systems’ functioning. This study aims to increase the application of the Functional Resonance Analysis Method (FRAM) in the requirements elicitation process. Specifically, understanding variability and its role in enhancing the requirements elicitation and specification process for the design/redesign of IT systems in complex socio-technical systems deployed in building maintenance is the main goal. This study proposes the merging of human factors and ergonomics (HFE) and Resilience Engineering concepts with Software Engineering. A case study was performed with workers to produce requirements specifications for work order issuing activity. This case study indicates the usefulness of the proposed approach for the specification of functional requirements to redesign the IT system examined. FRAM enables inferences to be made from hidden or fuzzy situations that are often not expressed by system users or are not detected by the system designer.

Magnetic topological insulators are narrow-gap semiconductor materials that combine non-trivial band topology and magnetic order 1 . Unlike their nonmagnetic counterparts, magnetic topological insulators may have some of the surfaces gapped, which enables a number of exotic phenomena that have potential applications in spintronics 1 , such as the quantum anomalous Hall effect 2 and chiral Majorana fermions 3 . So far, magnetic topological insulators have only been created by means of doping nonmagnetic topological insulators with 3 d transition-metal elements; however, such an approach leads to strongly inhomogeneous magnetic 4 and electronic 5 properties of these materials, restricting the observation of important effects to very low temperatures 2 , 3 . An intrinsic magnetic topological insulator—a stoichiometric well ordered magnetic compound—could be an ideal solution to these problems, but no such material has been observed so far. Here we predict by ab initio calculations and further confirm using various experimental techniques the realization of an antiferromagnetic topological insulator in the layered van der Waals compound MnBi 2 Te 4 . The antiferromagnetic ordering  that MnBi 2 Te 4  shows makes it invariant with respect to the combination of the time-reversal and primitive-lattice translation symmetries, giving rise to a ℤ 2 topological classification; ℤ 2  = 1 for MnBi 2 Te 4 , confirming its topologically nontrivial nature. Our experiments indicate that the symmetry-breaking (0001) surface of MnBi 2 Te 4 exhibits a large bandgap in the topological surface state. We expect this property to eventually enable the observation of a number of fundamental phenomena, among them quantized magnetoelectric coupling 6 – 8 and axion electrodynamics 9 , 10 . Other exotic phenomena could become accessible at much higher temperatures than those reached so far, such as the quantum anomalous Hall effect 2 and chiral Majorana fermions 3 . An intrinsic antiferromagnetic topological insulator, MnBi 2 Te 4 , is theoretically predicted and then realized experimentally, with implications for the study of exotic quantum phenomena.

The objective of this research was to evaluate the learning styles for algebra concepts of the students of the industrial engineering program of the University of Santander, Valledupar, Cesar, Colombia. A descriptive study was developed, consisting of 40 algebra students and 6 mathematics teachers, the questionnaire is self-administered elaborated with a dichotomous scale for the student and for interpretation of the means, a scale was designed based on a scale between zero and five that reveals the score obtained in said test, the styles studied were active, reflective, theoretical and pragmatic. Concluding that the predominant style is the pragmatic and theoretical, which allowed to select and apply strategies aimed at generating interactivity between students and teachers around the knowledge of algebra.

This research establishes the relationship that has had the development of the skills of scientific reasoning and the patterns of use of tools and resources of information and communication technology (ICT). For that, it is necessary to use Lawson Test and to have into account ICT National Standards for students that USA International Society for Technology in Education (ISTE) suggest. Also, this paper is tackled from a non-experimental design featuring a correlational - transectional range. The population consists of 2035 students from a higher education institution of the Colombian Caribbean coast. Besides, stratified random sampling is used defining, defining strata and a representative sample for academic programs. Personal survey was used to collect information. The existence of relationship between scientific reasoning skills and patterns of use of information and communication technology was confirmed.

The main objective of this work was to elaborate a sugary syrup from the use of Guácimo fruit extract (Guazuma Ulmifolia Lam) using the leaching method (solid - liquid), which can be used as a partial or total substitute for sugar. The experimental design that was applied for the extraction process was a factorial design 23; the data obtained were evaluated with the software Statgraphics. Once the extracts were obtained, physico-chemical tests were carried out and reductive sugars and dextrose equivalent were determined in each one. To obtain the syrup, the four extracts having the highest% ED were concentrated at constant temperature and time (50 ° C and 4 hours); The determination of the presence of reducing sugars was done using the techniques of colorimetric analysis (miller's method) and chromatography (HPLC). The products that were obtained during the process were extreme conversion syrups with a range of dextrose equivalents of 90.13% - 98.27%. The syrup that obtained the highest percentage of equivalent dextrose (J3) was subjected to a sensory hedonic test, which consisted of 3 samples of sweetened coffee at different concentrations of sweet sugar syrup and sugar (sucrose), where M1 contained 80% sugar syrup of guácimo and 20% of table sugar. M2 contained 50% guácimo sugar syrup and 50% table sugar. M3 contained 100% sugar guacimo syrup and 0% table sugar. The results showed that the mixture that obtained the highest organoleptic acceptance was M2, followed by M3, which states that the syrup can substitute partially the common sugar. The above data allow the guácimo fruit to be taken into account as an alternative raw material for the production of sugar syrups and other products aimed at human consumption.

The purpose of this article is to publicize the evaluation of the effectiveness of Opuntia ficus indica as a coagulant during the treatment of raw water from the middle basin of the Guatapurí River, in the Department of Cesar, Colombia. Tuna coagulant is purely organic; it has been shown by phytochemical studies performed on Opuntia ficus indica the presence of some minerals among some others; contains glycides or carbohydrates. The evaluation was carried out using the jug test equipment, which operated by varying the revolutions per minute (20, 30 and 40), keeping the mixture fast at 125 rpm and settling for 30 minutes. The samples were physically characterized (Turbidity, Alkalinity, pH and total suspended solids) taking into account the methods specified for parameter in the Standard Methods. With samples of 345.9 NTU and 2799.1 NTU at optimal doses of 658.75 mg/L and 1976.3 mg/L respectively, removals up to 97% and 99.5% were observed in the same order. It was shown that the variation of the slow mixture only influenced with the sample of 2799.1 NTU, being the most effective treatment at 30 RPM.

This paper describes an exploratory situated approach for the design, development, standardization, and implementation of line-oriented flight training (LOFT) in a major airline. LOFT was conceived in aviation industry to be a practical application of crew resource management (CRM) concepts. The situated approach combines a set of methods and techniques from ergonomics and human factors disciplines. These methods were supported by social construction enabling the involvement and participation of different actors of the operational, tactical, and strategic level of the company. Under this framework, situated design is progressively established by socially constructed patterns up to a situated design comprising the construction of scenarios, training tools, procedures, structures, organization, flight documents, operations, and further training management contents. Our findings indicate that LOFT situated design, framed by social construction, can be applied to any aviation system with a specific culture and organization, which may be different from the ones that were implicitly or explicitly taken into account during the development of general LOFT guidelines.

The tamarind (Tamarindus indica L.), is from the legume family and is native to the tropics. The fruit is curved, which the shell is bright brown and its flattened oval seeds, joined together by fibers. It is a highly rustic fruit tree, since it can thrive in poor or marginalized soils, with little or no irrigation and minimal care, in relation to other tropical fruit trees. The objective of this work was to establish the formulation process to obtain a hydrating drink based on Tamarindus indica L., To obtain the drink, the following formulations were made; formulation 1 (6% tamarind pulp - 94% H2O), formulation 2 (9% tamarind pulp - 91% H2O) and formulation 3 (12% tamarind pulp - 88% H2O), keeping the amounts of electrolytes and carbohydrates constant added to the formulation. As the main result for the formulation of the drink, there is the following sequence: Harvesting of the fruit, Selection and classification of the raw material, Pulping, Storage of the pulp, Formulation, Mixing, Pasteurization, Packaging and Storage.

Cocoa is an American tree of Amazonian origin, also known as cacaotero, since by cocoa it usually refers to the fruit that gives said tree. The proposed research is developed on the emerging paradigm, for which a dialectical synthesis is assumed from the use of qualitative and quantitative methods in a complementary way. Not limited to the forms and sources of information the collection of information, and the analysis of results, for which we take as a reference the contribution from the experience of Cocoa Producers and Experts in the production and marketing of cocoa, as a fundamental part of the construction of knowledge, and grant the same level of importance to the information obtained from multiple sources of information obtained in the year 2020. For the collection of information, the instruments are applied in three phases: the first consists of field visits to interview 5 cocoa producers and 5 experts in cocoa marketing. The second, search and systematization of documents and the third phase is a comparative analysis of the sources of information mentioned above. For the establishment of cocoa cultivation and to obtain adequate productions, aspects of great relevance must be taken into account, such as critical climatic factors such as temperature and rain. The layout and density of the agroforestry system. This activity aims to make a defined and organized distribution within the lot of each of the plant species that are going to be planted, seeking a better use of the soil. It was verified the effort made by small producers to integrate in the management of their cocoa crops, the processes, harvesting and post-harvest activities that are carried out to obtain dried cocoa almonds for marketing.

Using angle-resolved photoelectron spectroscopy (ARPES), we investigate the surface electronic structure of the magnetic van der Waals compounds MnBi\\(_4\\)Te\\(_7\\) and MnBi\\(_6\\)Te\\(_{10}\\), the \\(n=\\)~1 and 2 members of a modular (Bi\\(_2\\)Te\\(_3\\))\\(_n\\)(MnBi\\(_2\\)Te\\(_4\\)) series, which have attracted recent interest as intrinsic magnetic topological insulators. Combining circular dichroic, spin-resolved and photon-energy-dependent ARPES measurements with calculations based on density functional theory, we unveil complex momentum-dependent orbital and spin textures in the surface electronic structure and disentangle topological from trivial surface bands. We find that the Dirac-cone dispersion of the topologial surface state is strongly perturbed by hybridization with valence-band states for Bi\\(_2\\)Te\\(_3\\)-terminated surfaces but remains preserved for MnBi\\(_2\\)Te\\(_4\\)-terminated surfaces. Our results firmly establish the topologically non-trivial nature of these magnetic van der Waals materials and indicate that the possibility of realizing a quantized anomalous Hall conductivity depends on surface termination.