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Techniques for the identification of organizational knowledge management requirements
No full textPurpose: This paper aims to explore the requirements of organizational knowledge management initiatives using requirements engineering techniques, identifying the optimal techniques configuration and serving as a management tool for knowledge engineers. Design/methodology/approach: The method is selection attributes. Knowledge management enablers are characterized and mapped with the coverage capabilities of requirements engineering techniques, using the attributes of the elicited object and a box-plot analysis. The information is gathered from 280 references, 32 companies and 16 experts in requirements engineering. Findings: Requirements of organizational knowledge management initiatives are got optimally by combining interviews, use cases, scenarios, laddering and focus group techniques. The requirements of structure and processes are more complex to identify, while culture requirements are the best covered. Research limitations/implications: Knowledge management enablers are analyzed according to the current studies and comprehension of engineering techniques. Practical implications: Knowledge engineers need to consider the coverage capabilities of engineering techniques to design an optimal requirement identification and meet the objectives of organizational knowledge acquisition initiatives. Requirement engineers can improve the requirements identification by a staged selection process. Social implications: The requirements of knowledge management initiatives that impact the community can be identified and traced to ensure the knowledge objectives. Requirements related to culture and people, like shared values, beliefs, and behaviors, are also considered. Originality/value: To the best of the authors knowledge, this is the first study about formal requirement identification of knowledge management initiatives in the organizational context, providing the optimal configuration. A novel staged process is proposed for requirements engineering techniques selection, analyzing the enablers at component level and identifying the attributes associated with the elicited object. © 2019, Emerald Publishing Limited
Removal of dyes from aqueous solutions by adsorbent prepared from coffee residues
No full textThis study reports the production of an adsorbent material derived from extracted coffee residues using phosphoric acid and zinc chloride as activating agents. The structural features of the materials were characterized using different analytical techniques. The BET surface areas were found between 3.81 m2.g-1 y 176.27 m2.g-1, while the FTIR analysis showed the formation of oxygenated functional groups, which are active in the adsorption process. These materials were evaluated as adsorbents for the removal of methylene blue from aqueous solution. Batch adsorption tests were performed at room temperature and the effects of contact time and, initial dye concentration was investigated. The equilibrium adsorption results were complied with Langmuir isotherm model and its maximum monolayer adsorption capacity was 15.92 mg.g-1. Adsorption kinetics studies indicated that the pseudo second order model yielded the best fit for the kinetic data. This typical dependence of methylene blue uptake on kinetic studies indicated the adsorption process to be both chemisorption and diffusion controlled. The experimental data obtained in the present study indicate that coffee residues are suitable candidates for use as adsorbents in the removal of cationic dyes. © 2019 Published under licence by IOP Publishing Ltd
Optical properties of n-type asymmetric triple ?-doped quantum well under external fields
No full textWe present a theoretical investigation about the the influence of external electric, magnetic and non-resonant intense laser fields on intersubband-related second harmonics generation (SHG) and the nonlinear optical rectification (NOR) coefficients in n-type asymmetric triple ?-doped quantum wells (QWs). A particular design of asymmetric triple ?-doped QW with L w = 200 Å width and, respectively, in the left side, central and right side, and doping concentrations is taken into account. For QWs under the combined effect of the external electric, magnetic and laser fields, the time-dependent wave equation is modified by using Kramers-Henneberger transformation and the dipole approximation. The subband energy spectra and the electronic wave functions are obtained by solving numerically the wave equation. The originality of this work can be presented as; (i) The results explain NOR and SHG characteristics of triple QW depending on external field effects in detail. The effects of the electric, magnetic and laser field on transition energies and NOR, SHG characteristics are presented detail. (ii) In addition to, the alternativeness to each other of the external fields is discussed by probing the features of SHG and NOR under the strong and weak regimes of external fields. (iii) These nonlinear optical responses to the external fields are compared, researching the optimum cases for these optical specifications. (iv) The control of SHG through the external fields in triple ?-doped QWs reveals to be easier and more precise. © 2020 IOP Publishing Ltd
Relationship between securities that make up the yield curve of the Colombian public debt market [Relación entre títulos que conforman la curva de rendimientos del mercado de deuda pública colombiano]
No full textBased on the information of the yield curve (CR) of Colombia, it is sought to find the existing relationships between the titles that compose it; specifically sets of two or three assets; and with this analyze whether or not there are cointegration or equilibrium relations in the long term. Taking this into account, it was found that there are cointegration relations between October 18 and July 20 for the case of peer analysis and for the case of analysis of trios, a strong relationship was found between October 2018, November 2018 and July 2020. These results are obtained optimally using a Python algorithm that looks for all possible relationships between the considered assets. This algorithm is part of the contribution of this work, and also the finding and the evidence that there are cointegrated assets in the yield curve of Colombia. With this, medium-term debt portfolio investment strategies can be designed. © 2019 AISTI
Effects of single vacancy on electronic properties of blue-phosphorene nanotubes
No full textWe investigate the electronic properties of blue-phosphorene nanotubes using density functional theory first-principle calculations, taking into account, in particular, the presence of atom vacancies in the structure. The study considers both zigzag and armchair achiral configurations and reports on the structure and the electron energy states of the nanostructure. Compared to pristine blue-phosphorene nanotubes, which exhibit values of the fundamental bandgap between one and two electron-volts. For atomic single vacancies, the incorporation of spin-polarization helps to identify the induction of localized mid-gap states in the blue phosphorene nanotubes. The difference of energy between the highest near-valence and lower near-conduction localized states is, approximately, of 0.5 eV. Also the increase of the single vacancies concentration leads to the formation of additional bands that change the energy gap of the system. © 2020 The Author(s). Published by IOP Publishing Ltd
Latin American Chronicle: Magazines, natural haBitat of quality journalisM [CrÓnica latinoamericana: Las revistas, hÁbitat natural del periodismo bien hecho]
No full textThis article is a result of the research project Crónica latinoamericana actual: lo maravilloso real. Análisis del periodismo narrativo de Alberto Salcedo Ramos presented by the author for the degree of Doctor in Lenguajes y Manifestaciones Artísticas y Literarias at Universidad Autónoma de Madrid and tries to show the role played by magazines in the vitality of the current Latin American chronicle. The fact that this has been developed by magazines links it to New Journalism in the United States, and such publications have allowed a boom in narrative journalism in Latin America. © 2019 Universidad de Chile, Facultad de Filosofia y Humanidades, Departamento de Literatura. All rights reserved
Moderating effect of the digital divide of e-commerce
No full textPurpose: The purpose of this paper is to examine whether the digital divide has a moderating effect on the technological factors that affect the adoption of electronic commerce. Design/methodology/approach: This study proposes an exploratory empirical model that integrates the basic variables of e-commerce adoption through the use of the technology adoption model, making an extension with the facilitating conditions and the digital divide as a moderating variable. A digital survey was randomly distributed in Colombia, reaching a final sample of 745 electronic buyers. Findings: The explanatory result validates that the perception of the digital divide negatively moderates the influence of the variables related to internet technology on the use of e-commerce. Originality/value: This one of the first studies that analyzes the effect of the digital divide on the adoption of e-commerce. © 2019, Emerald Publishing Limited
Modeling of insolvency risk in health sector companies using logit models [Modelación del riesgo de insolvencia en empresas del sector salud empleando modelos logit]
No full textThis article shows the prediction of the level of insolvency in companies that are not listed on the stock exchange belonging to the health sector for one and two years in advance, using the multiple logistic regression analysis based on indicators of liquidity, indebtedness, financial structure and pro_tability. The period 2010@@@2013 is taken as a reference for a sample of 3,930 companies categorized by size (large, medium, small and micro), and classified by their level of high, medium and low insolvency risk. The success results of the models are between 70% and 80% for each of the years, validating the results obtained throughout the study. © 2019, Universidad Pablo de Olavide
Comparison of the effects generated by the dry-soft grinding and the photodeposition of Au and Pt processes on the visible light absorption and photoactivity of TiO2
No full textThe influence of dry-soft grinding and photodeposition of gold (Au) or platinum (Pt) in the improvement of the photoactivity of TiO2 synthesized by an integrated sol-gel and solvothermal method was studied. TiO2 was modified by a dry-soft grinding process in a planetary ball mill (TiO2(G)). Subsequently, Au or Pt particles were photodeposited in both unmodified TiO2 and TiO2(G) obtaining Au-TiO2, Pt-TiO2, Au-TiO2(G), and Pt-TiO2(G) materials. The photoactivity of the materials was evaluated in the phenol photodegradation under simulated solar radiation. Pt-TiO2 showed the greatest degree of photoactivity improvement in comparison with TiO2 and TiO2-P25. The dry-soft grinding process led to a high photocatalytic activity of TiO2(G) that was similar to Pt-TiO2 activity as consequence of a slight increase in the crystallinity in TiO2(G) due to an additional anatase formation in comparison with TiO2. However, further photocatalytic improvement in TiO2(G) were not achieved with the addition of Au or Pt. Therefore, the dry-soft grinding treatment and noble metal deposition led to similar improvements in the photocatalytic activity of TiO2 for phenol oxidation. © 2019 IOP Publishing Ltd
Medios de comunicación y movilidad cognitiva: series políticas en streaming, Puebla, México 2018
Get PDFThis research work analyzes the influence of television series that are broadcast through streaming platforms in Mexico. The research took a representative sample of 400 young people, who were surveyed to know the impact of these communication products in the construction of their perception, political participation and political culture in the last elections of July 2018. Through a quantitative methodology and the use of the statistical sample, belonging to 12 thousand 884 voters from 18 to 19 years old from the capital of Puebla, from the electoral district 12; it was found that there is a low degree of appropriation, the young people surveyed do not determine their perception of Mexican politics from the series they visualize, cognitive mobility is therefore not determinant for this case of the study presented.Este trabalho de pesquisa analisa a influência de séries de televisão que são transmitidas através de plataformas de streaming no México. A pesquisa levou uma amostra representativa de 400 jovens, que foram pesquisados ??para conhecer o impacto desses produtos de comunicação na construção de sua percepção, participação política e cultura política nas últimas eleições de julho de 2018. Através de uma metodologia quantitativa e do uso de a amostra estatística, pertencente a 12 mil 884 eleitores de 18 a 19 anos da capital de Puebla, do distrito eleitoral 12; Verificou-se que há um baixo grau de apropriação, os jovens pesquisados ??não determinam sua percepção da política mexicana a partir da série que visualizam, a mobilidade cognitiva não é, portanto, determinante para este caso do estudo apresentado.Este trabajo de investigación analiza la influencia que tienen las series televisivas que se difunden por medio de las plataformas streaming en México. La investigación tomó una muestra representativa de 400 jóvenes, que fueron encuestados para conocer la incidencia que tienen estos productos comunicativos en la construcción de su percepción, participación política y cultura política en las pasadas elecciones de julio de 2018. Mediante una metodología cuantitativa y el uso de la muestra estadística, perteneciente a 12 mil 884 electores de 18 a 19 años de la capital poblana, del distrito 12 electoral; se encontró que existe un grado de apropiación bajo, los jóvenes encuestados no determinan su percepción sobre la política mexicana a partir de las series que visualizan, la movilidad cognitiva por tanto no es determinante para este caso del estudio presentado