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Traditionally, two different policies to access the radio spectrum have coexisted: licensed regulation, whereby the rights to use specific spectral bands are granted in exclusivity to an individual operator; or unlicensed regulation, according to which certain spectral bands are declared open for free use by any operator or individual following specific rules. While these paradigms have allowed the wireless communications sector to blossom in the past, in recent years they have evidenced shortcomings and given signs of exhaustion. For instance, it is quite usual to encounter fully overloaded mobile communication systems coexisting with unused contiguous spectral bands. This clearly advocates for a more flexible and dynamic allocation of the spectrum resources which can only be achieved with the advent of the so-called cognitive radios and networks. This whitepaper provides an accurate description of priority research activities and open challenges related to the different functionalities of cognitive radios and networks. First, we outline the main open problems related to the theoretical characterization of cognitive radios, spectrum sensing techniques as well as the optimization of physical layer functionalities in these networks. Second, we provide a description of the main research challenges that arise from a system point of view: MAC protocol optimization, traffic modelling, RRM strategies, routing paradigms or security issues. Next, we point out other problems related to the practical hardware implementation of cognitive radios, giving especial emphasis to sensing capabilities, reconfigurability and cognitive control and management. Finally, we succinctly report on a number of current activities related to the standardization of cognitive radio systems., Comment: AEI eMOV White Paper, published 04/11/2011, In Spanish

This paper presents a comprehensive review of stochastic processes, with a particular focus on Markov chains and jump processes. The main results related to queuing systems are analyzed. Additionally, conditions that ensure the stability, or ergodicity, of such systems are presented. The paper also discusses stability results for queuing networks and their extension to visiting systems. Finally, key contributions concerning the Probability Generating Function, an essential tool in the analysis of the aforementioned processes, are introduced. The review is conducted from the perspective of queuing theory, grounded in the Kendall-Lee notation, emphasizing stability results and the computation of performance measures based on the specific characteristics of each process., Comment: in Spanish language

This study proposes a methodology using OpenAlex (OA) for tracking Open Access publications in the case of Argentina, a country where a self-archiving mandate has been in effect since 2013 ( Law 26.899, 2013). A sample of 167,240 papers by researchers from the National Council for Scientific and Technical Research (CONICET) was created and analyzed using statistical techniques. We estimate that OA is able to capture between 85-93% of authors for all disciplines, with the exception of Social Sciences and Humanities, where it only reaches an estimated 47%. The availability of papers in Open Access was calculated to be 41% for the period 1953-2021 and 46% when considering exclusively the post-law period (2014-2021). In both periods, gold Open Access made up the most common route. When comparing equal periods post and pre-law, we observed that the upward trend of gold Open Access was pre-existing to the legislation and the availability of closed articles in repositories increased by 5% to what is estimated based on existing trends. However, while the green route has had a positive evolution, it has been the publication in gold journals that has boosted access to Argentine production more rapidly. We concluded that the OA-based methodology, piloted here for the first time, is viable for tracking Open Access in Argentina since it yields percentages similar to other national and international studies. En este estudio se propone una metodolog\'ia utilizando OpenAlex (OA) para monitorear el acceso abierto (AA) a las publicaciones cient\'ificas para el caso de Argentina, pa\'is donde rige el mandato de autoarchivo -Ley 26.899 (2013)-. Se conform\'o una muestra con 167.240 art\'iculos de investigadores del Consejo Nacional de Investigaciones Cient\'ificas y T\'ecnicas (CONICET) que se analizaron con t\'ecnicas estad\'isticas. Se estim\'o que OA puede representar entre 85-93% de los autores para todas las disciplinas, excepto Ciencias Sociales y Humanidades, donde solo alcanza al 47%. Se calcul\'o que 41% de los art\'iculos publicados entre 1953-2021 incluidos en la fuente est\'an en AA, porcentaje que sube a 46% al considerar exclusivamente el periodo post ley (2014-2021). En ambos periodos es la v\'ia dorada la que representa mayor proporci\'on. Al comparar periodos iguales post y pre ley, se observ\'o que la tendencia en alza de la v\'ia dorada era preexistente a la legislaci\'on y la disponibilidad de art\'iculos cerrados en repositorios aument\'o un 5% a lo que se estima en base a tendencias existentes. Se concluye que si bien la v\'ia verde ha tenido una evoluci\'on positiva, ha sido la publicaci\'on en revistas doradas lo que ha impulsado m\'as r\'apidamente el acceso a la producci\'on argentina. Asimismo, que la metodolog\'ia basada en OA, piloteada aqu\'i por primera vez, es viable para monitorear el AA en Argentina ya que arroja porcentajes similares a otros estudios nacionales e internacionales., Comment: in Spanish (en Espa\~nol)

The HIV/AIDS pandemic is a global issue that has unequally affected several countries. Due to the complexity of this condition and the human drama it represents to those most affected by it, several fields have contributed to solving or at least alleviating this situation, and the information systems (IS) field has not been absent from these efforts. With the importance of antiretroviral therapy (ART) as a starting point, several initiatives in the IS field have focused on ways to improve the adherence and effectiveness of this therapy: mobile phone reminders (for pill intake and appointments), and mobile interfaces between patients and health workers are popular contributions. However, many of these solutions have been difficult to implement or deploy in some countries in the Global South, which are among the most affected by this pandemic. This paper presents one such case. Using a case-study approach with an extreme-case selection technique, the paper studies an m-health system for HIV patients in the Kalangala region of Uganda. Using Heeks' design-reality gap model for data analysis, the paper shows that the rich interaction between social context and technology should be considered a central concern when designing or deploying such systems., Comment: 30 pages, in Spanish

The bibliographic review is a fundamental phase in a research project, and it must guarantee that the most relevant information in the field of study is obtained. Our main objective was to know the works related to the Internet of medical things, from now on (IoMT). We analyzed a total of 535 articles searched in association for Computing Machinery in Adelante ACM, Web of Science and Scopus the search domain was IoMT, we established 3 parameters, (problematic, artifact and artifact evaluation), this according to the Research of Design Science in Adelante DSR, is a research approach for the construction of artifacts to provide a useful solution to a problem in each domain. The equation (Internet of things AND mesh) resulted in 535, (Internet of things AND medicine) a total of 417 and finally (Internet of medical things AND mesh) with 8, this means that there is a lot to investigate in this research domain. The advantages identified in this type of topology is to carry messages from one node to another by different paths, there can be absolutely no interruption in communications, each server has its own communications with all other servers. Health and IT issues have been drastically influenced by the large data from IoMT devices. In this paper, we conducted a review of the scientific literature and mapped research trends on the IoMT paradigm in the health domain. Finally, this paper expands on the literature, and the findings of this study can serve as a basis for future studies., Comment: in Spanish language

This paper introduces the Relative Inequality Index at the Maximum (IDRM), a novel and intuitive measure designed to capture inequality within a population, such as income inequality. The index is based on the idea that individuals experience varying levels of inequality depending on their position within the distribution, particularly with respect to those at the top. The key assumption is that for individuals in lower positions, inequalities referenced to the top positions have greater impact on their well-being and the inequality relative to maximum is the most critical. The IDRM fulfills desirable theoretical properties which were used for its evaluation and comparison against widely accepted measures in inequality literature. From this perspective, the IDRM is shown to be as robust as traditional measures and outperforms the Gini and Dalton indices by satisfying eight out of nine key properties, including decomposability across population subgroups. In a comparative analysis using income data from 58 countries and microdata from Mexico, with the Gini, Theil, and Atkinson indices as benchmarks, the IDRM demonstrates superior consistency, sensitivity to inequality, reduced bias in grouped data, and enhanced precision. This index reflects the varying forms of income distribution, showing heightened sensitivity to the magnitude of inequality., Comment: 38 pages, in Spanish language, 6 tables, 4 figures

In this paper, a methodology for modelling a dynamic equivalent of an external area is presented. The equivalent consists of a generator with series impedance and a parallel load (generalized Ward equivalent), integrating control systems such as the Automatic Voltage Regulator (AVR) and the Speed Regulator (GOV) in a test system known as PST-16. The main objective is to identify the parameters of the control systems and other parameters inherent to the generator so that the response of the equivalent system is similar to the response of the complete system., Comment: in Spanish language

The analysis of social media information has undergone significant evolution in the last decade due to advancements in artificial intelligence (AI) and machine learning (ML). This paper provides an overview of the state-of-the-art techniques in social media mining, with a practical application in analyzing trends in the 2024 French legislative elections. We leverage natural language processing (NLP) tools to gauge public opinion by extracting and analyzing comments and reactions from the AgoraVox platform. The study reveals that the National Rally party, led by Marine Le Pen, maintains a high level of engagement on social media, outperforming traditional parties. This trend is corroborated by user interactions, indicating a strong digital presence. The results highlight the utility of advanced AI models, such as transformers and large language models (LLMs), in capturing nuanced public sentiments and predicting political leanings, demonstrating their potential in real-time reputation management and crisis response., Comment: in Spanish language. Keywords: social media mining, AI, ML, NLP, French elections, public opinion analysis, transformers, large language models

In this paper we continue our study of the scientific research carried out at the Institute of Physics of the National University of La Plata during the first half of the 20th century, and of the important role played by the physicist Ramon G. Loyarte. Based on his studies, alone or in collaboration with members of the Institute, towards the end of the 1920s Loyarte proposed the possible existence of a new quantum of rotational energy in the mercury atom. This idea raised criticism and generated a fierce scientific controversy that reached the national and international academic media. We analyse this controversy by studying the comments that appeared in international review journals. We also study Loyarte's activities in politics and science policy in Argentina in the 1930s and 1940s, where he was responsible for interesting political and scientific initiatives., Comment: Article in Spanish, PDF document. Other related documents available at https://www.universoeinstein.com.ar/einsteinargentina.htm

The use of an efficient coverage planning method is key for autonomous navigation in agricultural environments, where a robot must cover large areas of crops. This paper generally reviews the current state of the art of coverage path planning methods. Two widely used techniques applicable to agricultural environments are described in detail. The first consists of breaking down a complex field with obstacles into simpler subregions known as cells, to subsequently generate a coverage pattern in each of them. The second analyzes spaces composed of parallel strips through which the robot must circulate, in order to find the optimal order of visiting strips that minimizes the total distance traveled. Additionally, the combination of both techniques is discussed in order to obtain a more efficient global coverage plan. This analysis was conceived to be implemented with the soybean crop weeding robot developed at CIFASIS (CONICET-UNR)., Comment: in Spanish language

The aim of this paper is to provide a classification of multilingual and plurilingual electronic lexicographic resources which would enable, one the one hand, the implementation of quantitative and qualitative criteria to produce a typological taxonomy of lexicographical tools, such as dictionaries, as opposed to platforms and websites and, on the other, the distinction of multilingual and plurilingual resources in terms of their larger or lesser prototyping degree. In addition to offering a thorough description of the different resources, this paper also puts forward some parameters and typological proposals to define and demarcate a number of electronic resources, particularly multilingual dictionaries and portals, while also outlining, and even questioning, the object of study of multilingual and plurilingual lexicography., Comment: 25 pages, in Spanish language

This paper studies the problem of Zero-Knowledge Protocol (ZKP) and elliptic curve cryptographic implementation in a computationally limited environment, such as, the smart cards, using Java Card. Besides that, it is explained how the zero-knowledge protocol was selected to implement it on a smart card and how the benchmarking was conducted to select this protocol. The paper also shows a theoretical development to implement the ZKP protocol using elliptic curve cryptography. Keywords: Authentication; Zero-knowledge; Cryptography; Elliptic Curve; Java card; Smart cards, Comment: 16 pages, in Spanish

Estas notas son las memorias del cursillo dictado en el XXII Congreso Colombiano de Matem\'aticas en la Universidad del Cauca en Popay\'an - Colombia. El objetivo de este escrito es brindar un acercamiento a la teor\'ia de m\'odulos sobre el anillo de operadores diferenciales de una variedad algebraica suave. These are the lecture notes of a short course given at the XXII Colombian Congress of Mathematics held at Universidad del Cauca in Popay\'an - Colombia. The aim of this paper is to provide an introduction to the theory of modules over rings of differential operators over a smooth algebraic variety., Comment: Paper in Spanish language

This paper presents a platform to facilitate the deployment of applications in Internet of Things (IoT) devices. The platform allows to the programmers to use a Function-as-a-Service programming paradigm that are managed and configured in a Platform-as-a-Service web tool. The tool also allows to establish interoperability between the functions of the applications. The proposed platform obtained faster and easier deployments of the applications and the resource usages of the IoT devices also were lower in relation to a deployment process based in containers of Docker., Comment: in Spanish language

Large companies are fully engaged in their digital transformation, specifically in developing strategic Business Intelligence (BI) projects. They have a Digital Strategy and top-level executives managing the change. BI projects are also being carried out in SMEs. In this paper, we present the results of an interpretative study conducted on a sample of SMEs from different sectors carrying out BI projects. We study whether BI maturity models are valid for SMEs and their usefulness for analysing the projects and evaluating the results at the end of the project., Comment: 15 pages, in Spanish language

The digitization of the productive ecosystem related to human-machine interaction has become a priority for small and medium-sized enterprises. Particularly to face the challenges of Industry 4.0 and advanced digital skills in the workplace. From the research point of view, digitization opens a global scenario for the generation of opportunities for learning in existing manufacturing systems. Mainly, traditional environments must deal with competitive pressures to incorporate new technologies and adapt the skills of workers. In this paper is presented the iDIGIT4L project, which was envisaged to research and develop a digitization ecosystem where people and systems interact in order to transform industrial processes in an intelligent and predictive way. The project contributes with a three-tier human-machine learning methodology that provides augmented and bi-directional interaction in a traditional manufacturing scenario. It is based on the implementation of a non-intrusively integrated digital twin, characterizing an old industrial milling machine for learning through knowledge models supported by the experience of skilled workers. As a result, it has been possible to simultaneously update the functionalities of the industrial system and the digital skills of the workers, becoming an integral part of the digital twin., Comment: in Spanish language

In this paper we present a study of the applicability and feasibility of quantum-inspired algorithms and techniques in tensor networks for industrial environments and contexts, with a compilation of the available literature and an analysis of the use cases that may be affected by such methods. In addition, we explore the limitations of such techniques in order to determine their potential scalability., Comment: 10 pages, in Spanish language, 5 figures

Liquid crystals are the prototype of the so-called soft condensed matter. In simple terms they are "structured liquids" that historically have received a lot of interest because they help to generate new concepts and knowledge in Physics, and possess important electro--optical applications, e. g., in displays of mobile computers and telephones. More recently, it has been discovered that liquid crystals could be applied in fabrication of metamaterials and in biomedicine where they are potentially useful for tissue identification, controlled drug delivery and detection of bacteria and viruses. However, in Mexico, liquid crystals courses are included only in a few undergraduate programs on Physics being elective in most of the cases. Therefore, literature for teaching about liquid crystals in Spanish is scarce. In this paper we will discuss about elementary Physics of liquid crystals and the mathematical tools that permit to analyze them. We will explain, mainly, how to analytically characterize the symmetry and order of static uniaxial nematic liquid crystals, the most simple of all liquid crystal phases. We will conduct this explanation in basic terms, suitable for science and engineering students at intermediate undergraduate level, with knowledge about linear algebra and vector calculus, willing to approach for the first time to this subject. Our goal is to support the Latin American scientific community in preparing human resources in this field. The article is written in Spanish to contribute to the establishment and communication of concepts that only exist in other languages in the specialized literature., Comment: In Spanish, 13 figures

This paper presents the design of an artificial vision system prototype for automatic inspection and monitoring of objects over a conveyor belt and using a Smart camera 2D BOA-INS. The prototype consists of a conveyor belt and an embedded system based on an Arduino Mega card for system control, and it has as main peripherals the smart camera, a direct current motor, a photoelectric sensor, LED illumination and LEDs indicating the status (good or defect) of each evaluated object. The application of the prototype is for educational purposes, so that undergraduate, master and diploma students can simulate a continuous production line, controlled by an embedded system, and perform quality control by monitoring through a visual system and a personal computer. This allows implementing the topics of embedded systems, artificial vision, artificial intelligence, pattern recognition, automatic control, as well as automation of real processes., Comment: 8 pages, 16 figures, in Spanish language

The objective of this work is to analyze the usefulness to transform the information to measure sports performance. This analysis is carried out within the field of basketball due to the existing tradition in this sport in data collection, although it is easily adaptable to any other sport. As a result, a modification of the Performance Index Rating (PIR) is proposed to measure sports performance. The results obtained are illustrated from the statistics of Larry Bird, Earvin Johnson, Michael Jordan and Kobe Bryant throughout their careers and can serve to optimize the process of player renewal/firing/hiring in the design of a roster or to aid decision-making in awarding individual awards as best player of a season., Comment: 16 pages, working paper (in spanish)

Mendel performed his experiments from 1856 and 1863, presented his results in two meetings of the Natural Science Society in Brunn in February and March of 1865, and finally published them in the iconical paper of 1866, Versuche uber Plflanzenhybriden. Two main translations to Spanish are available: the one done by Prevosti in 1977, and a more recent one by Gomez-Graciani in 2014. Both were translated from the English version of Druery and Bateson. Here, we present the first direct translation from German to Spanish of this paper. This new version corrects some errors detected in the previous versions, uses a more agile style and includes the Darwinized terms pointed out by Abbot and Faribanks in a recent paper (Genetics, 204(2):401-405, 2016; doi: 10.1534/genetics.116.194613)., Comment: in Spanish language

This paper describes how the field of Combinatorial Semantics has contributed to the design of three prototypes for the automatic generation of argument patterns in nominal phrases in Spanish, French and German (Xera, Combinatoria and CombiContext). It also shows the importance of knowing about the argument syntactic-semantic interface in a production situation in the context of foreign languages. After a descriptive section on the design, typologie and information levels of the resources, there follows an explanation of the central role of the combinatorial meaning (roles and ontological features). The study deals with different semantic f ilters applied in the selection, organization and expansion of the lexicon, being these key pieces for the generation of grammatically correct and semantically acceptable mono- and biargumental nominal phrases., Comment: 18 pages, in Spanish language. C\'irculo de ling\"u\'istica aplicada a la comunicaci\'on, 2022

In this paper, the deductive system for double propositional logic DL and gamma DL existential graphs are presented. It rigorously proves the consistency of the DL and that the DL theorems correspond exactly to the valid existential graphs of gamma DL. When the language of DL is restricted to the language of classical propositional logic, the restriction associated with gamma DL coincides with the valid existential graphs of Charles Sanders Peirce's alpha system. It turns out that intuitionistic propositional logic theorems are DL theorems; furthermore, when the language of DL is restricted to the language of IL, the restriction associated with gamma DL coincides with the valid existential graphs of Arnold Oostra's intuitionistic alpha system. As a consequence, it is inferred that gamma LD has as particular cases, the alpha existential graphs of LC and LI. Finally, in DL, the Aristotelian definitions of truth and falsity are derived, with which the ability of DL to solve a version of the liar paradox, where LC and LI fail, is illustrated., Comment: in Spanish language. arXiv admin note: text overlap with arXiv:2310.02035

This survey paper, written in spanish, is an extended version of lecture notes for a mini-course taught at the 2022 Summer School in Geometric Group Theory, which took place in the Centro de Ciencias Matem\'aticas in Morelia, Mexico in July 2022. Its main aim is to give an introduction to the study of non-positively curved cube complexes, and through these, to introduce the reader to geometric group theory., Comment: 38 pages, in Spanish language, lots of figures, accepted for publication at Memorias de la Sociedad Matem\'atica Mexicana

We study the Jesuit mission churches in America, which for almost two centuries were the most representative constructions in the process of Christian evangelisation on the continent until the expulsion of the Order in 1767. The main objective is to discern possible orientation patterns in the structures studied and to evaluate whether these orientations are related to the rising of the sun or other celestial bodies on the local horizon, as suggested by the texts of early Christian writers, which could provide important and novel information about their history and construction. Archaeoastronomical fieldwork has been carried out in the past in two large regions of South America: the historic provinces of Paraquaria and Chiquitan\'ia (eastern present-day Bolivia). These data must now be interpreted within a broader cultural and geographical context. Thus, in order to obtain a more complete picture of religious architecture on the continent, it is necessary to analyse and compare the results with the orientation of Jesuit churches built in the 17th and 18th centuries in North America (viceroyalty of New Spain). We approached this project through the historical and cultural analysis of the former mission sites and by means of satellite imagery. In this paper we present some preliminary results we have reached., Comment: Article in Spanish. Paper presented at The 63rd meeting of the Argentine Astronomical Society, held in C\'ordoba, Argentina, 25-29 October 2021

In this article I will explore some uses of the concept of Boltzmann brains in comics (Marvel's The Incredible Hercules), an animated sitcom (Futurama) and a film (Guardians of the Galaxy Vol. 2). Previous similar uses of the concept (before Boltzmann brains were named as such) will be traced, and potential influences on these artistic outlets will be analysed. I will also explain how the concept was used in a novel published in 2018 by Ediciones Ayarmanot in Buenos Aires (La inevitable resurrecci\'on de los cerebros de Bolzmann, to be published in English as "Iridio Ennui vs. the Boltzmann brains"). After briefly reviewing the second law of thermodynamics and the concept of Boltzmann brains, the paper analyses the four artistic instances in which has been used, answering two key questions: a) How entities who (in theory) appear in the foam of interstellar space and suddenly disappear are presented in the fictional scenario? b) How the plot justifies that Boltzmann brains could exist for a time long enough to allow them to become viable fictional characters?, Comment: In Spanish, 26 pages, 14 figures, 1 table. This is a slightly extended version of a paper to be published in the proceedings of the Science Fiction Convention Portico, Universidad Tecnologica Nacional, Sede Regional Cordoba, Argentina

In this work we employ the methods of archaeoastronomy to analyze the orientation, possibly astronomical, of numerous groups of chullpa funerary towers, mainly from the 12th to 16th centuries, located in the Lauca River valley of the central Bolivian highlands. Despite their great historical relevance, both regarding the beliefs and funerary customs of the local populations and the characteristics of the landscape in the highlands, little is known about the relationship of these mortuary monuments with the sky. Several authors, from chroniclers of the colonial era to more modern explorers, indicate that the tomb towers of these regions are oriented in such a way that important parts of their structure (in general, the entrances of the chullpas) point towards the sunrise on the eastern horizon, in order to be imbued with the first rays of the Sun. However, the sunrise changes its location noticeably at different times of the year. Given the lack of written information or other forms of original documentation, in order to affirm the use of a systematic orientation, it is necessary to measure a statistically significant number of monuments. We present here the results of the analysis of the precise spatial orientation of the entrances of 80 towers measured in situ during field work in the Lauca River valley. We find that, except for a few, all the buildings have the openings' axes oriented towards the east and within the solar range, between the extreme azimuths of the annual movement of the Sun as it crosses the local horizon, with a notable concentration of entrances that point slightly towards the north of due east. Our work is the first systematic study of the orientations of the chullpa towers of the Lauca River and can provide crucial information to understand the evolution and scope of the chullpa phenomenon in the Bolivian highlands and in the entire surrounding region., Comment: Article in Spanish, PDF document. To be published in the journal Anales de la Asociaci\'on F\'isica Argentina

This work presents a three-dimensional geometric resolution method to calculate the complete inverse kinematics of a 7-degree-of-freedom articulated arm, including the hand itself. The method is classified as an analytical method with geometric solution, since it obtains a precise solution in a closed number of steps, converting the inverse kinematic problem into a three-dimensional geometric model. To simplify the problem, the kinematic decoupling method is used, so that the position of the wrist is calculated independently on one hand with information on the orientation of the hand, and the angles of the rest of the arm are calculated from the wrist., Comment: in Spanish language

SAPPO is a high-precision, low-cost and highly scalable indoor localization system. The system is designed using modified HC-SR04 ultrasound transducers as a base to be used as distance meters between beacons and mobile robots. Additionally, it has a very unusual arrangement of its elements, such that the beacons and the array of transmitters of the mobile robot are located in very close planes, in a horizontal emission arrangement, parallel to the ground, achieving a range per transducer of almost 12 meters. SAPPO represents a significant leap forward in ultrasound localization systems, in terms of reducing the density of beacons while maintaining average precision in the millimeter range., Comment: in Spanish language