Design architectures of the CMOS power amplifier for 2.4 GHz ISM band applications: An overview

Power amplifiers (PAs) are among the most crucial functional blocks in the radio frequency (RF) frontend for reliable wireless communication. PAs amplify and boost the input signal to the required output power. The signal is amplified to make it sufficiently high for the transmitter to propagate the required distance to the receiver. Attempted advancements of PA have focused on attaining high-performance RF signals for transmitters. Such PAs are expected to require low power consumption while producing a relatively high output power with a high efficiency. However, current PA designs in nanometer and micrometer complementary metal–oxide semiconductor (CMOS) technology present inevitable drawbacks, such as oxide breakdown and hot electron effect. A well-defined architecture, including a linear and simple functional block synthesis, is critical in designing CMOS PA for various applications. This article describes the different state-of-the art design architectures of CMOS PA, including their circuit operations, and analyzes the performance of PAs for 2.4 GHz ISM (industrial, scientific, and medical) band applications

Evaluación y rehabilitación neuropsicológica en oncología pediátrica.

Objetivo. El presente trabajo tiene como objetivo el estudio de los efectos neuropsicológicos a largo plazo del cáncer infantil y sus tratamientos así como plantear propuestas para la rehabilitación cognitiva. Método. El método ha consistido en una revisión sistemática de los resultados en la literatura científica acerca de los efectos de la quimioterapia y la radioterapia sobre el SNC y en las funciones cognitivas y conductuales detectados a través de estudios de neuroimagen como calcificaciones y cambios en la sustancia blanca. Presentamos, además, el protocolo de evaluación neuropsicológica ejemplificado con un diagnóstico frecuente que presenta deterioro generalizado. Proponemos un programa de rehabilitación neuropsicológica basado en el Attention Process Training (APT) de Mateer y Sohlberg. Resultado. La radioterapia craneal y el metotrexato producen alteraciones generalizadas que se reflejan en déficit neuropsicológicos: CI, atención, memoria, habilidades académicas y motoras. Conclusiones. El avance en los tratamientos ha supuesto la disminución del número e intensidad de las secuelas. No obstante, sigue siendo frecuente que en los tumores del SNC y en las leucemias aparezcan alteraciones cognitivas y conductuales. La evaluación neuropsicológica continua y los modelos de sustancia blanca nos ayudan a entender estos efectos a largo plazo. Asimismo, esta evaluación es fundamental para diagnosticar los déficit evitando falsas atribuciones y expectativas inadecuadas. Destacamos la necesidad de una unidad de seguimiento y del trabajo interdisciplinario para promover la calidad de vida de los niños con cáncer

A Robust Controller for Multilevel Distributed Generation Based Islanded Microgrid

The power requirement throughout the world is continuously increasing due to the technological development and change in human life. The unplanned uses of the fossil fuel to fulfill the electric demand hampers the future resources that will make resource threat for the future generation. Non-renewable energy sources are the alternative of fossil fuel that increases the possibility of the microgrid (MG) technology that not only reduces the excess pressure on fossil fuel but also produces clean energy. The control of proper operation of the MG is essential for maintaining stable voltage, current and power delivery. The stable profile of the performance of MG may be greatly hampered due to the presence of load dynamics as well as uncertainties that is responsible to damage the system. This chapter represents an improved design of fuzzy logic control approach to regulate the stable and tracking performance of the MG against different faults and uncertainties

Savonius wind turbine blade design and performance evaluation using ANN-based virtual clone: A new approach

The drag based Savonius wind turbine (SWT) has shown immense potential for renewable power generation in built-up areas under complex urban wind conditions. While a series of studies have been conducted on improving SWT's efficiency, optimal performance has yet to be achieved using traditional design approaches such as experimental and/or computational fluid dynamics methods. Recently, artificial intelligence and machine learning have been widely used in design optimization. As such, an ANN-based virtual clone can be an alternative to traditional design methods for wind turbine performance determination. Therefore, the main goal of this study is to investigate whether ANN-based virtual clones are capable of determining the performance of SWTs with a shorter timeframe and minimal resources compared to traditional methods. To achieve the objective, an ANN-based virtual clone model is developed. Two sets of data (computational and experimental) are used to validate and determine the efficacy of the proposed ANN-based virtual clone model. Using experimental data, the model's fidelity is over 98%. The proposed model produces results in one-fifth the time of the existing simulation (based on the combined ANN + GA metamodel) method. The model also reveals the location of the dataset's optimized point for augmenting the turbine's performance

Pencil graphite as electrode platform for free chlorine sensors and energy storage devices.

Multifunctional and low-cost electrode materials are desirable for the next-generation sensors and energy storage applications. This paper reports the use of pencil graphite as an electrode for dual applications that include the detection of free residual chlorine using electro-oxidation process and as an electrochemical energy storage cathode. The pencil graphite is transferred to cellulose paper by drawing ten times and applied for the detection of free residual chlorine, which shows a sensitivity of 27 μA mM-1 cm-2 with a limit of detection of 88.9 μM and linearity up to 7 mM. The sample matrix effect study for the commonly interfering ions such as NO3-, SO42-, CO32-, Cl-, HCO3- shows minimal impact on free residual chlorine detection. Pencil graphite then used after cyclic voltammogram treatment as a cathode in the aqueous Zn/Al-ion battery, showing an average discharge potential plateau of ~1.1 V, with a specific cathode capacity of ~54.1 mAh g-1 at a current of 55 mA g-1. It maintains ~95.8% of its initial efficiency after 100 cycles. Results obtained from the density functional theory calculation is consistent with the electro-oxidation process involved in the detection of free residual chlorine, as well as intercalation and de-intercalation behavior of Al3+ into the graphite layers of Zn/Al-ion battery. Therefore, pencil graphite due to its excellent electro-oxidation and conducting properties, can be successfully implemented as low cost, disposable and green material for both sensor and energy-storage applications

A Statewide Multi-Institutional Study of Asymptomatic Pretreatment Testing of Radiation Therapy Patients for SARS-CoV-2 in a High-Incidence Region of the United States

Purpose: Our purpose was to establish the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in asymptomatic patients scheduled to receive radiation therapy and its effect on management decisions. Methods and Materials: Between April 2020 and July 2020, patients without influenza-like illness symptoms at four radiation oncology departments (two academic university hospitals and two community hospitals) underwent polymerase chain reaction testing for SARS-CoV-2 before the initiation of treatment. Patients were tested either before radiation therapy simulation or after simulation but before treatment initiation. Patients tested for indications of influenza-like illness symptoms were excluded from this analysis. Management of SARS-CoV-2-positive patients was individualized based on disease site and acuity. Results: Over a 3-month period, a total of 385 tests were performed in 336 asymptomatic patients either before simulation (n = 75), post-simulation, before treatment (n = 230), or on-treatment (n = 49). A total of five patients tested positive for SARS-CoV-2, for a pretreatment prevalence of 1.3% (2.6% in north/central New Jersey and 0.4% in southern New Jersey/southeast Pennsylvania). The median age of positive patients was 58 years (range, 38-78 years). All positive patients were white and were relatively equally distributed with regard to sex (2 male, 3 female) and ethnicity (2 Hispanic and 3 non-Hispanic). The median Charlson comorbidity score among positive patients was five. All five patients were treated for different primary tumor sites, the large majority had advanced disease (80%), and all were treated for curative intent. The majority of positive patients were being treated with either sequential or concurrent immunosuppressive systemic therapy (80%). Initiation of treatment was delayed for 14 days with the addition of retesting for four patients, and one patient was treated without delay but with additional infectious-disease precautions. Conclusions: Broad-based pretreatment asymptomatic testing of radiation oncology patients for SARS-CoV-2 is of limited value, even in a high-incidence region. Future strategies may include focused risk-stratified asymptomatic testing

Towards electric digital twin grid: Technology and framework review

The major hindrances in the energy system are ecological consciousness, lack of clean and sustainable energy management, insufficient energy distribution–transmission–optimization, expensive power transfer costs, and increased customer knowledge of energy charges. Thus why, universal access to the grid with high cybersecurity, and reliability is needed to solve all these challenges. The digital twin concept turns a new dimension of technology into the world. Electric Digital Twin grid can perform online analysis of the grid in real-time and integrates all the past and present data and express the current grid status to the producers and consumers and also predicts the future grid status. Thus, the power grid transmission loss and location of the overheated line and power connection missing can be detected in addition decision-making and self-healing can possible. The future prediction saves the power grid from small to long accidents such as power outages and even blackout problems. The whole consumers and nation feel relief from these types of accidents and saves from large economic and business loss. The blockchain-enabled digital twin grid provides high security for the grid from cyberattacks. The paper conveys the framework of the electric digital twin grid and the concept of the DT grid processing and the way of serving the producer, prosumers, consumers even the whole nation in infrastructure, education, research, economic, business, and political development

Towards electric digital twin grid: Technology and framework review

The major hindrances in the energy system are ecological consciousness, lack of clean and sustainable energy management, insufficient energy distribution-transmission-optimization, expensive power transfer costs, and increased customer knowledge of energy charges. Thus why, universal access to the grid with high cybersecurity, and reliability is needed to solve all these challenges. The digital twin concept turns a new dimension of technology into the world. Electric Digital Twin grid can perform online analysis of the grid in real-time and integrates all the past and present data and express the current grid status to the producers and consumers and also predicts the future grid status. Thus, the power grid transmission loss and location of the overheated line and power connection missing can be detected in addition decision-making and self-healing can possible. The future prediction saves the power grid from small to long accidents such as power outages and even blackout problems. The whole consumers and nation feel relief from these types of accidents and saves from large economic and business loss. The blockchain-enabled digital twin grid provides high security for the grid from cyberattacks. The paper conveys the framework of the electric digital twin grid and the concept of the DT grid processing and the way of serving the producer, prosumers, consumers even the whole nation in infrastructure, education, research, economic, business, and political development. 2022 The Author(s)The publication of this article was funded by Qatar National Library, Qatar .Scopu