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Linking of built environment inequalities with air quality: a case study
No full textIn developing countries, where few air quality stations and studies exist, measuring the spatial gradient of nitrogen dioxide (NO2) in urban areas is challenging. Our research explores the linking the of built environment with air quality by developing a model that allows relating NO2 with transport, land use, socioeconomics, and built environment characteristics. For the model estimation, we installed and quantified 114 diffusion tubes from Gradko© in Barranquilla, Colombia, a Caribbean city. Our results indicated that the lowest NO2 values occurred in remaining green areas, reduced traffic, and places that favor walking. However, the city design and current conditions of the built environment generate inequalities in exposure to air pollution. Low-income inhabitants are exposed to higher NO2 values than wealthier people. Therefore, planning sustainable and equitable cities should involve reducing NO2 concentrations by designing sound strategies for adequate mobility and developing an urban design that promotes walking
Determination of soil Infiltration values with In situ tests and direct moisture and precipitation measurements
No full textRain events are the cause of many landslides that occur on slopes causing a loss of strength by decreasing the effective tension. In this article, it performs the geo-mechanical characterization of a soil slope located in Colombia which has been defined as a zone of instability, where there is instrumentation consisting of a volumetric soil moisture meter and a pluviometric station. With this information, we intend to determine the times of saturation and evacuation of rainwater in the mentioned soil considering too the frequency of events. In that sense, an experimental calibration of moisture meter installed on the site is done, and the Water Retention Characteristic Curve is constructed to determine the variation of the effective efforts as soil moisture and permeability of the material and the relationship is a determined index empty as soil structure to know its maximum saturation level. The main results showed an increase in the correlation of soil moisture as depth increases, on the other hand, the permeability coefficient obtained was low, which is typical of soils with low permeability, a situation that was also evidenced in the differences of the suction curves obtained; additionally it was found that at greater depths more accumulated precipitation is required to reach saturation moisture, which corresponds to the infiltration process in the soils, the void ratio found and the mentioned permeability coefficient
Identity, Autonomy and Self-Determination: Legal Recognition of Indigenous Communities and Peoples in Colombia and Chile
No full textEste artículo analiza la distinción jurídica, histórica y sociológica entre pueblo originario y comunidad indígena como un estudio comparado entre los pueblos nativos de Chile y Colombia, sus conceptos y reconocimientos en distintos ordenamientos jurídicos y tratados internacionales; asimismo la importancia que tuvo la Corona Española en el desarrollo de las sociedades indígenas y su paso hacia la integración al mundo del Derecho. Tiene como objetivo principal describir la evolución legal y jurisprudencial de los derechos fundamentales de las comunidades y pueblos de ambos países, destacando la autonomía y determinación de estos al momento de autor reconocerse como un colectivo social con una identidad, cultura y patrimonio propio de la época precolombina. El diseño metodológico corresponde a un estudio bibliográfico–documental. Dentro de los resultados de este artículo de investigación se encuentra como a propósito de las etnias o pueblos originarios, a simple vista, existe en esta aproximación una forma distinta de abordar esta temática. Con relación a los hallazgos investigados, se identifica una evolución social progresiva en estas comunidades a lo largo del tiempo, lo que les ha permitido resistir a conflictos bélicos y a la formación del Estado. Como conclusiones preliminares, se destaca un concepto jurídico perdurable sobre la importancia de la identidad en las comunidades y pueblos indígenas, subrayando su relevancia a lo largo de la historia.This article analyzes the legal, historical and sociological distinction between native people and indigenous community as a comparative study between the native peoples of Chile and Colombia, their concepts and recognition in different legal systems and international treaties, as well as the importance of the Spanish Crown in the development of indigenous societies and their integration into the world of law. Its main objective is to describe the legal and jurisprudential evolution of the fundamental rights of the communities and peoples of both countries, highlighting their autonomy and determination at the moment of recognizing themselves as a social group with an identity, culture and heritage from pre-Columbian times. The methodological design corresponds to a bibliographic-documentary study. Within the results of this research article, it is found how, at first sight, there is in this approach a different way of approaching this subject. In relation to the investigated findings, a progressive social evolution is identified in these communities throughout time, which has allowed them to resist to war conflicts and the formation of the State. As preliminary conclusions, an enduring legal concept on the importance of identity in indigenous communities and peoples is highlighted, underlining its relevance throughout history
Dimethylformamide impurities as propylene polymerization inhibitor
No full textThis research study examined how the use of dimethylformamide (DMF) as an inhibitor affects the propylene polymerization process when using a Ziegler–Natta catalyst. Several experiments were carried out using TiCl4/MgCl2 as a catalyst, aluminum trialkyl as a cocatalyst, and different amounts of DMF. Then, we analyzed how DMF influences other aspects of the process, such as catalyst activity, molecular weight, and the number of branches in the polymer chains obtained, using experimental and computational methods. The results revealed that as the DMF/Ti ratio increases, the catalyst activity decreases. From a concentration of 5.11 ppm of DMF, a decrease in catalyst activity was observed, ranging from 45 TM/Kg to 44 TM/Kg. When the DMF concentration was increased to 40.23 ppm, the catalyst activity decreased to 43 TM/Kg, and with 75.32 ppm, it dropped even further to 39 TM/Kg. The highest concentration of DMF evaluated, 89.92 ppm, resulted in a catalyst productivity of 36.5 TM/Kg and lost productivity of 22%. In addition, significant changes in the polymer’s melt flow index (MFI) were noted as the DMF concentration increased. When 89.92 ppm of DMF was added, the MFI loss was 75%, indicating a higher flowability of the polymer. In this study, it was found that dimethylformamide (DMF) exhibits a strong affinity for the titanium center of a Ziegler–Natta (ZN) catalyst, with an adsorption energy (Ead) of approximately −46.157 kcal/mol, indicating a robust interaction. This affinity is significantly higher compared to propylene, which has an Ead of approximately −5.2 kcal/mol. The study also revealed that the energy gap between the highest occupied molecular orbital (HOMO) of DMF and the lowest unoccupied molecular orbital (SOMO) of the Ziegler–Natta (ZN) catalyst is energetically favorable, with a value of approximately 0.311 eV
Artificial Intelligence and its impact on due process
No full textEl debido proceso se entiende como una norma de derecho fundamental y una disposición positiva destinada a preservar la seguridad jurídica. Además, es vista como una institución jurisdiccional encaminada a la configuración de las garantías procesales al interior de una actuación judicial. Pero, su relación con la inteligencia artificial cobra un especial sentido en los modernos estados constitucionales. En el presente artículo analiza el impacto hermenéutico-procesal en la administración de justicia, de la relación y conexidad entre el debido proceso y la inteligencia artificial. Esto, se realizó bajo una metodología analítica y descriptiva. Como conclusiones preliminares, se establece que existe una nueva razón práctica jurídica asociada a la relación necesaria y no contingente entre el derecho y la IA. Especialmente, se responderá en concreto a cuatro puntos: (i). El debido proceso y su estructura como norma fundamental-procedimental en los sistemas de jurisprudencia. (ii). Que es la inteligencia artificial aplicada al derecho: Perspectivas teóricas y conceptuales (iii). Los jueces y la administración de justicia mediados por la IA: nuevos sistemas meta-normativos y su hermenéutica judicial. Y (iv). Jurisprudencia algorítmica: La decisión judicial artificial y su impacto procesal en la administración de justicia.
Due process is a rule of fundamental law and a positive provision to preserve legal certainty. Furthermore, it is seen as a jurisdictional institution that configures procedural guarantees within a judicial action. However, its relationship with artificial intelligence has a special meaning in modern constitutional states. This article will analyze the hermeneutical-procedural impact on the administration of justice and the relationship and connection between due process and artificial intelligence. This was conducted using analytical and descriptive methodology. As preliminary conclusions, it is established that a new legal practical reason is associated with the necessary and non-contingent relationship between law and AI. Four points will be specifically answered: (i). Due process and its structure as a fundamental procedural norm in jurisprudence systems. (ii). What is artificial intelligence applied to law: Theoretical and conceptual perspectives (iii). Judges and the administration of justice mediated by AI: new meta-normative systems and their judicial hermeneutics. and (iv). Algorithmic jurisprudence: The artificial judicial decision and its procedural impact on the administration of justice.
Corrigendum to “Developed teamwork optimizer for model parameter estimation of the proton exchange membrane fuel cell” [Energy Rep. 8 (2022) 10776–10785]
No full textThe authors regret to inform that the affiliation of the author Andrey Leonidovich Poltarykhin is not full. Andrey Leonidovich Poltarykhin’ s full affiliation is the following: Doctor of Economic Sciences Plekhanov Russian University of Economics, Moscow, Russian Federation 117997, Moscow, Stremyannyi Alley, 36, Russian Federation ORCID ID: http://orcid.org/0000-0003-2272-2007. So please add Plekhanov Russian University of Economics. The authors would like to apologize for any inconvenience caused
El reto de las revistas científicas y la inteligencia artificial
No full textEn un mundo en constante evolución, donde el conocimiento se convierte en el recurso más valioso y esencial para la sociedad, las revistas científicas emergen como pilares fundamentales para la comprensión profunda de los fenómenos que les rodean. Son los vehículos por los cuales el conocimiento se difunde y se pone al alcance de la humanidad. A través de sus páginas, los investigadores comparten sus hallazgos, teorías y análisis con sus pares de todo el mundo. Hoy en día la tecnología avanza a pasos agigantados, las revistas científicas se encuentran en una encrucijada desafiante. La irrupción de la Inteligencia Artificial (IA) ha revolucionado la forma en que se interactúa con la información y ha planteado profundos cuestionamientos sobre el futuro de la publicación científica. Uno de los desafíos que enfrentan las revistas científicas es la velocidad de la producción y distribución de información habilitada por la IA. Mientras que las revistas tradicionales pueden requerir semanas o meses para revisar y publicar un artículo, la IA puede generar análisis y resultados en cuestión de segundos. No obstante, surge la preocupación que estos procesos automatizados puedan pasar por alto matices y contextos importantes que los revisores humanos detectarían
Ammonia mediated silver nanoparticles based detection of bisphenol a, an endocrine disruptor, in water samples after vortex-assisted liquid–liquid microextraction
No full textBisphenol A (BPA), an alkylphenolic compound, is one of the most polluting and hazardous organic chemicals. Its routine detection is, however, still rather expensive due to high-cost equipment. In this context, we applied the effect caused by BPA to the optical properties of surfactant-stabilized silver nanoparticles further modified with the use of ammonia (AgNP-NH3) to develop a simple and quantitative approach for BPA determination. The experimental conditions of the AgNP-NH3 probe were adjusted to establish a stable and sensitive response toward BPA in aqueous media. The use of probe dispersion measured at a wavelength of 403 nm enabled a limit of detection of 2.0 nmol L−1 (0.5 ng mL−1), with a linear response as a function of a concentration of BPA ranging from 10 to 120 nmol L−1 (from 2.2 to 27 ng mL−1). The use of vortex-assisted liquid–liquid microextraction ensured the application of selective determination to real tap and stream water samples, with recoveries ranging from 85.0 to 111%. The protocol developed herein is simple, sensitive, and selective, does not require the use of toxic labeling agents, and can be easily adapted for the routine analysis of BPA in different real samples
Cavitation preventation in centrifugal pumps using ANSYS
No full textIn this paper, a computational fluid dynamic (CFD) model was developed to assess cavitation phenomenon and its local effects on a centrifugal pump. The model included the temperature of the fluid, rotational velocity, and geometric configuration of the suction. The model was validated using the pump characteristics curves of the manufacturer with an error of 5%. Also, the minimum pressure contours and the vapor volume fraction were plotted. These contours show the pump boundary conditions (temperature and angular velocity) before cavitation occurs. Thus, the impeller zone where the cavitation phenomenon is more susceptible to occurrence was identified. In addition, this analysis determined characteristic parameters such as the limit on fluid temperature, the limiting angular velocity of the pump and the ratio between the diameters of the suction pipe and the pump inlet diameter. The proposed methodology is aimed as a reference for the study of local operating parameters to avoid cavitation in various types of hydraulic pumps
Design-based system performance assessment of a combined power and freshwater cogeneration system
No full textIn this research, the design and use of combined systems for the simultaneous production of water, heat, and energy have been proposed, and, to fulfill the water, electricity, and heat demands of a hotel, modeling of the multi-effect evaporative desalination (MED) and combined heat and power (CHP) generation system was done. Then, the design of these two systems was administered in a combined way. This design was applied in order to evaluate the economy of the combined system compared to separate systems. The performed scenario was executed every 24 h during the two seasons of the year. The genetic algorithm was used to optimize this system, and it was considered the objective function to minimize the annual costs. The results showed that the nominal capacity of the gas turbine and backup boiler in the CHP + MED + thermal energy storage (TES) system was (14%) larger and (8.2%) smaller, respectively, compared to the CHP+ MED system. In addition, by using the energy storage tank in the combined CHP + MED system, 5.1% of the annual costs were reduced