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Topic Review
Class E Power Amplifier
This entry aims to solve a problem that exists with impedance matching networks in terms of extra cost and power loss of electronic components in a four-coil wireless power transfer (WPT) system using class E power amplifier as power supply, which is not conducive to the improvement of system efficiency and output power. A design method of sharing the resonant inductor in class E power amplifier and the excitation coil in the four-coil WPT system is proposed. This method comprehensively considers the output power and transfer efficiency of the system, the number of coil turns, coil size and many other factors. Compared with the traditional four-coil system using a class E power amplifier as a power supply, the proposed method simplified the system structure by leaving out a resonant inductor and load matching circuit, which can reduce the power loss of system and improve efficiency. Moreover, the precisely tuning of resonant inductor was not necessary, which improved the stability of the system. The correctness and feasibility of the parameter design method were verified by experiments. The experimental results showed that the output power of the system was increased by 18.7%, the efficiency was increased by 11%, and the transmission distance was up to 0.7 m, which is suitable for wireless power supply of electronics and sensors.
  • 882
  • 29 Oct 2020
Topic Review
Topologies for CMOS CP Circuits
CP design topologies have been analyzed with different design and process schemes in the last decades . 
  • 881
  • 08 Apr 2021
Topic Review
Types of Airborne Wind Energy Systems
Airborne wind energy (AWE) has received increasing attention, with the goal of achieving electricity generation solutions that may be used as a complement or even an alternative to conventional wind turbines. There are several ways to classify AWE systems, e.g., with respect to the means of electricity generation, the flight principles and operation, or the type of flying wing, to name a few. 
  • 881
  • 10 Jan 2023
Topic Review
Classification Tools Heart Rate Variability
Chronic stress is the main cause of health problems in high-risk jobs. Wearable sensors can become an ecologically valid method of stress level assessment in real-life applications. We sought to determine a non-invasive technique for objective stress monitoring. Data were collected from firefighters during 24-h shifts using sensor belts equipped with a dry-lead electrocardiograph (ECG) and a three-axial accelerometer. Levels of stress experienced during fire incidents were evaluated via a brief self-assessment questionnaire. Types of physical activity were distinguished basing on accelerometer readings, and heart rate variability (HRV) time series were segmented accordingly into corresponding fragments. Those segments were classified as stress/no-stress conditions. Receiver Operating Characteristic (ROC) analysis showed true positive classification as stress condition for 15% of incidents (while maintaining almost zero False Positive Rate), which parallels the amount of truly stressful incidents reported in the questionnaires. These results show a firm correspondence between the perceived stress level and physiological data. Psychophysiological measurements are reliable indicators of stress even in ecological settings and appear promising for chronic stress monitoring in high-risk jobs, such as firefighting.
  • 881
  • 28 Oct 2020
Topic Review
Small-Molecule Semiconductor-Based OFET Temperature Sensors
Organic small-molecule semiconductors offer many benefits over their polymer equivalents, including ease of production, greater purity, and increased charge carrier mobility. OFETs based on small-molecule semiconductors have been intensively investigated as sensors for a variety of applications, including gas sensing, chemical sensing, biosensors, and pressure sensing.
  • 881
  • 17 Jan 2022
Topic Review
Global Quality Management System in Systems of Systems
Quality Management in System of Systems (SoS) organizations are characterized by very complex products and organizational structures. Since SoS integrate multiple systems and technologies, the corresponding organizational systems are characterized by great complexity that includes sub-organizational substructures. 
  • 880
  • 08 Aug 2022
Topic Review
W-band MIMO GB-SAR for Bridge
This is a fast MIMO-GBSAR (Multiple-Input Multiple-Output Ground-Based Synthetic Aperture Radar) operating in W-band (77 GHz). The radar can complete a scan in less than 8 s. Furthermore, as its overall dimension is smaller than 230 mm, it can be easily fixed to the head of a camera tripod, which makes its deployment in the field very easy, even by a single operator. 
  • 880
  • 27 Oct 2021
Biography
Franklin Chang Díaz
Franklin Ramón Chang Díaz (April 5, 1950)[1] is a Costa Rican Chinese American mechanical engineer, physicist, former NASA astronaut. He is the founder and current CEO of Ad Astra Rocket Company[2] as well as a member of Cummins' board of directors.[3] He became an American citizen in 1977.[4] He is of Chinese (paternal side) and Costa Rican Spanish (maternal side) descent.[5] He is a veteran
  • 880
  • 18 Nov 2022
Topic Review
Exosomes and Glioma Treatment
More than 40 years ago, vesicle structures, similar to “cytoplasmic fragments” physiologically released, were identified in the cellular matrix. Their peculiarity was their ability to contain various materials, including ribosomes, which are involved in several pathological and physiological activities.These systems were defined as extracellular vesicles (EVs), and they include a wide variety of vesicles (from 30 nm to 5 μm) released from the plasma membrane (PM) of many different cell types into several bodily fluids. All EVs present a lipid bilayer membrane that surrounds a pool of genetic material, cytosolic proteins, or cellular debris. However, they significantly differ in terms of size, biogenesis, mechanisms, and function. Among these membrane vesicles, the most well-studied EVs are exosomes.  Exosomes have sizes ranging between 30 and 150 nm and represent a homogenous population of EVs released from cells when multivesicular bodies (MVBs) are fused with the membrane through inward budding in a highly regulated process. As natural carrier systems, exosomes present low immunogenicity, low toxicity, stability in the bloodstream, and efficient cell uptake due to their endogenous cellular tropism. Furthermore their ability to mediate intercellular communication allows their use as a promising therapeutic and diagnostic tool.
  • 880
  • 24 Nov 2020
Topic Review
Chrysler Pacifica (RU)
The Chrysler Pacifica is a minivan being produced by the Chrysler division of FCA US LLC. Despite sharing its name with a discontinued crossover, it is an all-new design replacing the Chrysler Town & Country. The minivan is produced with two powertrains, a 3.6-liter gasoline powered engine and a plug-in hybrid, marketed as Pacifica Hybrid. The plug-in hybrid version has a 16-kWh lithium-ion battery that can propel the car up to 33 mi (53 km) on electric power alone. The gasoline-only version of the Pacifica minivan went on sale in mid-2016, while the plug-in hybrid version became available in early 2017.
  • 880
  • 17 Oct 2022
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