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2022 ◽  
Vol 18 (1) ◽  
pp. 1-20
Author(s):  
Jia Zhang ◽  
Xiuzhen Guo ◽  
Haotian Jiang ◽  
Xiaolong Zheng ◽  
Yuan He

Research on cross-technology communication ( CTC ) has made rapid progress in recent years. While the CTC links are complex and dynamic, how to estimate the quality of a CTC link remains an open and challenging problem. Through our observation and study, we find that none of the existing approaches can be applied to estimate the link quality of CTC. Built upon the physical-level emulation, transmission over a CTC link is jointly affected by two factors: the emulation error and the channel distortion. Furthermore, the channel distortion can be modeled and observed through the signal strength and the noise strength. We, in this article, propose a new link metric called C-LQI and a joint link model that simultaneously takes into account the emulation error and the channel distortion in the In-phase and Quadrature ( IQ ) domain. We accurately describe the superimposed impact on the received signal. We further design a lightweight link estimation approach including two different methods to estimate C-LQI and in turn the packet reception rate ( PRR ) over the CTC link. We implement C-LQI and compare it with two representative link estimation approaches. The results demonstrate that C-LQI reduces the relative estimation error by 49.8% and 51.5% compared with s-PRR and EWMA, respectively.


2021 ◽  
Vol 39 (3) ◽  
pp. 83-108
Author(s):  
Vicente Monleón

La diversidad es condición sine qua non de la propia existencia, no entendida únicamente a nivel físico sino como cualquier diferencia entre personas. Por ello, esta se percibe como la suma de la normatividad y alteridad. Esta realidad se convierte en una de las pretensiones de la escuela actual, especialmente durante la Educación Infantil como periodo educativo en el que se asientan los valores de tolerancia y respeto. No obstante, se cuenta con barreras en cuanto a dicho paradigma inclusivo con elementos como la cultura visual de la imagen que en parte de sus producciones incluye un discurso separatista, clasista y en contra de la diferencia. Un ejemplo concreto radica en la colección “Los clásicos” Disney como conjunto cinematográfico que exalta la normatividad occidental opacando la alteridad, y presentándola como situación normalizada. Como consecuencia, se procede a un estudio de tipo mixto para mostrar los filmes de esta colección que presentan un tratamiento positivo e inclusivo de la alteridad y que sirven por tanto como recurso didáctico para las plantillas docentes de la etapa educativa de Educación Infantil. Con todo, una de las sub-categorías más destacadas en el conjunto analizado es la normalidad con la que se presentan las Necesidades Educativas Especiales y razas diferentes a la blanca occidental. Diversity is a sine qua non condition of existence and it should not be only understood on a physical level but also as any difference between people. For this reason, diversity is perceived as the sum of normativity and otherness. The approach of diversity has become one of the aims of present-day schools, especially during Early Childhood Education because this is the period when the values ​​of tolerance and respect are established. However, there are barriers to this inclusive paradigm. One of them comes from the visual culture of images because part of its productions includes a separatist, classist and anti-difference discourse. A concrete example lies in the Disney "classics". This set of films exalts Western regulations, presenting them as the norm and, therefore, overshadowing otherness. To tackle this situation, the present mixed-method study focuses on the analysis of those films within the Disney classics which present a positive and inclusive treatment of alterity. These films, therefore, serve as a pedagogical resource for Early Education teaching staff. One of the most prominent sub-categories emerging from the analyzed films is the normality with which special needs and ethnicities different from the white Western one are presented.


2021 ◽  
Vol 9 (9) ◽  
pp. 970
Author(s):  
Alfonso-Isidro López-Diaz ◽  
Miguel A. Gutiérrez ◽  
Andrés Ortega Piris ◽  
Emma Díaz-Ruiz-Navamuel ◽  
David Rodríguez-Rosa

This paper analysed the potentialities that have not yet been exploited of the Automatic Vessel Identification System on Medium Frequency (AVISOMEF) that was previously presented to the scientific community. This system expanded the spectrum of possibilities of the Global Maritime Distress and Safety System (GMDSS). By the time AVISOMEF was presented, one of the unexpected benefits was that it could constitute a platform capable of supporting a Maritime Communication Network on Medium Frequency; all remotely located vessels could communicate with each other by using AVISOMEF, making use of the new established network, within the geographic area of implementation, without needing to use satellite techniques. Medium frequency propagation is stable and is not subject to coverage restrictions. To conduct this experiment, we collaborated with the Spanish Maritime Safety Agency (SASEMAR). It was thanks to them that we gathered real-time information about the nationwide maritime traffic that navigated through the Spanish Search and Rescue jurisdiction waters from 2018 to 2020.


Author(s):  
Д.К. МАЗУРЕНКО

Рассмотрены вопросы повышения эффективности использования спектра частот при построении систем сотовой связи 5G и 6G, а также проблемы снижения вычислительных затрат при реализации алгоритма последовательного подавления взаимного влияния сигналов. Подробно проанализирована суть нового принципа неортогонального множественного доступа на основе парциального кодирования, а также проведено его сравнение с методом разделения сигналов по мощности Power Division Non-Orthogonal Multiple Access (Рй-NOMA). Результаты получены с помощью программы «Моделирование Telecomm», предназначенной для численного математического моделирования систем связи на физическом уровне. The article considers the increasing the efficiency of using the frequency spectrum when building 5G and 6G cellular communication systems and the problems of reducing computational costs when implementing an algorithm for sequential suppression of the mutual influence of signals. The essence of the new principle of non-orthogonal multiple access based on partial coding is analyzed in detail, and it is compared with the Power Division Non-Orthogonal Multiple Access (PD-NOMA) method. The results are obtained using the software Modeling Telecomm intended for numerical mathematical modeling of communication systems at the physical level.


2021 ◽  
Vol 12 ◽  
pp. 81-88
Author(s):  
Marcelo G. Cendoya ◽  
Graciela M. Toccaceli

A very attractive and relatively simple option to simulate a DC-DC converter is to use a hybrid model. In this case, the need to use very small simulation steps (as those necessary to simulate models carried out at the physical level) is avoided. Furthermore, unlike the averaged state-space models, it has the advantage that the model is valid throughout the entire working range of the converter and for both conduction modes (continuous and discontinuous). By simulating several renewable energy conversion systems incorporating DC-DC converters, the authors have discovered the true potential of this modeling method. Despite its inherent advantages, this approach to DC-DC converters simulation is not as widely adopted as it should be. This work tries to encourage the reader of its use in certain typical situations. In this article the implementation of the hybrid model of the DC-DC Buck-Boost converter, using Statechart techniques, is performed. This model was written in the Stateflow language, a tool from the MATLAB®/Simulink environment, and allowed the creation of a building block formed by the described converter model with adequate interfaces to the SimPowerSystem and Simulink environments. The block is validated by comparing simulation results, realized under different operating conditions, with calculations done employing well-known and proven formulas. As an example of the use of the presented block, a buck-boost DC-DC converter with voltage and current control loops is simulated, corroborating its correct performance


Author(s):  
Zakiyah Darajat Munthe ◽  
Elman Boy ◽  
Al Furqon

Introduction: An elderly is a stage of human development after adulthood and the last period of the human life cycle. As a person gets older, the disability increases in activities of daily life as a result of decreasing physical level. The aging process shows physiological, cognitive and psychological changes in the human body. Decreased components of fitness, such as muscle strength, balance and the cardiorespiratory system affect the development of disabilities. Therefore, in Islam there is prayer service, which can be an effort to improve the cardiorespiratory fitness of the elderly. Where, with prayer, it can become a sports medium that is both physical and spiritual.Aims: To determine the effect of movement on cardiorespiratory fitness in the elderly. Research method: This type of literature study is a literature review.Method: the method used in writing this article is English studies relevant to the topic was carried out using the PubMed, Google Scholar and Semantic Scholar databases, restricted from 2010 to 2020. The keywords used in the article search were elderly, prayer movement and cardiorespiratory fitness.Results: The effect of prayer movement on cardiorespiratory fitness is that it can improve blood circulation from the heart to the rest of the body, increase blood flow to the brain and increase lung elasticity.Conclusion: There is a significant effect of prayer movement on the increase in cardiorespiration of the elderly.


2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Eugenia Colafranceschi ◽  
Daniele Oriti

Abstract In recent years, the import of quantum information techniques in quantum gravity opened new perspectives in the study of the microscopic structure of spacetime. We contribute to such a program by establishing a precise correspondence between the quantum information formalism of tensor networks (TN), in the case of projected entangled-pair states (PEPS) generalised to a second-quantized framework, and group field theory (GFT) states, and by showing how, in this quantum gravity approach, discrete spatial manifolds arise as entanglement patterns among quanta of space, having a dual representation in terms of graphs and simplicial complexes. We devote special attention to the implementation and consequences of the label independence of the graphs/networks, corresponding to the indistinguishability of the space quanta and representing a discrete counterpart of the diffeomorphism invariance of a consistent quantum gravity formalism. We also outline a relational setting to recover distinguishability of graph/network vertices at an effective and physical level, in a partial semi-classical limit of the theory.


2021 ◽  
Vol 54 (6) ◽  
pp. 1-26
Author(s):  
Harley Vera-Olivera ◽  
Ruizhe Guo ◽  
Holanda Maristela ◽  
Ruben Cruz Huacarpuma ◽  
Ana Paula Bernardi Da Silva ◽  
...  

Modeling is one of the most important steps in developing a database. In traditional databases, the Entity Relationship (ER) and Unified Modeling Language (UML) models are widely used. But how are NoSQL databases being modeled? We performed a systematic mapping review to answer three research questions to identify and analyze the levels of representation, models used, and contexts where the modeling process occurred in the main categories of NoSQL databases. We found 54 primary studies where we identified that conceptual and logical levels received more attention than the physical level of representation. The UML, ER, and new notation based on ER and UML were adapted to model NoSQL databases, in the same way, formats such as JSON, XML, and XMI were used to generate schemas through the three levels of representation. New contexts such as benchmark, evaluations, migration, and schema generation were identified, as well as new features to be considered for modeling NoSQL databases, such as the number of records by entities, CRUD operations, and system requirements (availability, consistency, or scalability). Additionally, a coupling and co-citation analysis was carried out to identify relevant works and researchers.


2021 ◽  
Vol 46 (3) ◽  
pp. 17-32
Author(s):  
Daniel Augusto Barra De Oliveira ◽  
Edenilson dos Santos Niculau

In this work, two philosophical premises of science applied in the understanding of diseases and in the planning of drugs were studied. The first premise is reductionism. This idea is present in modern science when a problem can be reduced to the sum of its individual parts. Diseases can be understood as the metabolic action of few enzymes. Drugs can be planned through the mimicry of a specific enzymatic substrate. Biological molecules can be explained by the quantum theory applied to atoms and molecules. his idea has been the predominant way in modern science. On the other hand, there is a holistic view of the phenomenon. In this holistic view, the phenomenon must be understood as the whole. Drug design should be thought from a network of proteins, not just from a single enzymatic target. There is in fact a slight advantage in the reductionist method, because this philosophical view simplifies the problem. Today, a holistic view combined with methodological reductionism is used to develop new potential drugs.


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