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Topic Review
Unisys ICON
The ICON was a computer built specifically for use in schools, to fill a standard created by the Ontario Ministry of Education. It was based on the Intel 80186 CPU and ran an early version of QNX, a Unix-like operating system. The system was packaged as an all-in-one machine similar to the Commodore PET, and included a trackball for mouse-like control. Over time a number of GUI-like systems appeared for the platform, based on the system's NAPLPS-based graphics system. The ICON was widely used, mostly in high schools in the mid to late 1980s, but disappeared after that time with the widespread introduction of PCs and Apple Macintoshes. They were also known as the CEMCorp ICON, Burroughs ICON, and finally Unisys ICON when Burroughs and Sperry Corporation merged to form Unisys in 1986. The machine was also nicknamed the bionic beaver.
  • 704
  • 18 Oct 2022
Topic Review
Improvement in Light Extraction Efficiency
As one of the important performance indicators of Micro-LEDs, external quantum efficiency (EQE) refers to the ratio of the final emitted photon number to the injected carrier number, which can be obtained by the product of the light extraction efficiency (LEE) and internal quantum efficiency (IQE). Therefore, EQE can be improved by improving the LEE. 
  • 702
  • 13 Jul 2023
Topic Review
Design Improvements of DC Circuit Breaker
While traditional AC mechanical circuit breakers can protect AC circuits, many other DC power distribution technologies, such as DC microgrids (MGs), yield superior disruption performance, e.g., faster and more reliable switching speeds. However, novel DC circuit breaker (DCCB) designs are challenging due to the need to quickly break high currents within milliseconds, caused by the high fault current rise in DC grids compared to AC grids. In DC grids, the circuit breaker must not provide any current crossing and must absorb surges, since the arc is not naturally extinguished by the system. Additionally, the DC breaker must mitigate the magnetic energy stored in the system inductance and withstand residual overvoltages after current interruption. These challenges require a fundamentally different topology for DCCBs, which are typically made using solid-state semiconductor technology, metal oxide varistors (MOVs), and ultra-fast switches.
  • 702
  • 06 Sep 2023
Topic Review
Carbon Nanotube Films as Sensor Material
The photo-thermoelectric (PTE) effect in electronic materials effectively combines photo-absorption-induced local heating and associated thermoelectric conversion for uncooled and broadband photo-detection. Formation of heterogeneous material junctions across the carbon nanotube (CNT)-film-based PTE sensors, namely photo-detection interfaces, triggers the Seebeck effect with photo-absorption-induced local heating. Typical photo-detection interfaces include a channel–electrode boundary and a junction between P-type CNTs and N-type CNTs (PN junctions). While the original CNT film channel exhibits positive Seebeck coefficient values, the material selections of the counterpart freely govern the intensity and polarity of the PTE response signals. Based on these operating mechanisms, CNT film PTE sensors demonstrate a variety of physical and chemical non-destructive inspections. 
  • 701
  • 17 Jan 2023
Topic Review
Risks of Electric Vehicle Integration into Smart Cities
The integration of electric vehicles (EVs) into smart cities presents a promising opportunity for reducing greenhouse gas emissions and enhancing urban sustainability. However, there are significant risks and challenges associated with the integration of EVs into smart cities, which must be carefully considered.
  • 701
  • 20 Jul 2023
Topic Review
Detection of Phase/Switch Open-Circuit Faults in Multiphase Drives
Phase open-circuit (OC) failures in multiphase electric ac drives involve OCs in stator phases or in converter-machine connections, and switch/diode OCs are frequently dealt with similarly or identically. Thanks to the phase redundancy of multiphase drives (with more than three phases), their operation can be satisfactorily continued under a certain number of OCs.  Phase/switch OC faults can be regarded as one of the most usual electrical failures in ac drives, and for this reason a significant number of works are focused on the diagnosis of this undesired incident. The detection of OC faults and the identification of the affected phases have typically been mandatory tasks in order to ensure a proper postfault reconfiguration. 
  • 700
  • 01 Apr 2022
Topic Review
Grid-Forming Inverters
The electrical grid is predominantly characterized by synchronous generators (SGs). These generators provide a consistent voltage and frequency, facilitating the synchronization of VSIs and their connection at the point of common coupling (PCC) for injecting power into the main grid. These inverters operate as current sources and are known as grid-following inverters. The imperfections of grid-following inverters arise when the grid is absent, as this concept fails to produce instantaneous voltage and frequency set points. Therefore, this operating mode has been significantly modified, from following the grid to leading it. This concept is known as grid-forming (GFM) inverters, which can independently set up and keep the voltage and frequency within their nominal ranges without the need for the main grid.
  • 700
  • 29 Dec 2023
Topic Review
Development of the Generation of Solar Cells
Solar energy is of prime importance in all renewable energy sources as the Sun shines at the Earth for 8 to 10 h on average. Thus, heat can be harnessed to generate electricity, but solar cells are not substantially efficient because the materials used in them are quite costly and waste a considerable amount of energy, mostly as heat, which subsequently reduces the efficiency of the cell and increases the overall price as well. These challenges can be dealt with by designing more efficient, economical systems of storage and manufacturing PV cells with high efficacy. Scientists and engineers are more inclined toward advanced technologies and material manipulation to enhance the efficiency of solar energy and reduce its cost.
  • 699
  • 06 Jul 2023
Topic Review
Versatile Electronics for Microwave Holographic RADAR
The NATO SPS G-5014 project has shown the possibility of using a holographic RADAR for the detection of anti-personnel mines. To use the RADAR on a robotic scanning system, it must be portable, light, easily integrated with mechanical handling systems and configurable in its operating parameters for optimal performance on different terrains. The novel contribution is to use software programmable electronics to optimize performance and to use a time reference to obtain synchronization between the RADAR samples and the position in space, in order to make it easy to integrate the RADAR on robotic platforms. 
  • 697
  • 14 Oct 2022
Topic Review
Hydrogen Storage for Large-Scale, Long-Term Energy Storage
In the process of building a new power system with new energy sources as the mainstay, wind power and photovoltaic energy enter the multiplication stage with randomness and uncertainty, and the foundation and support role of large-scale long-time energy storage is highlighted. Considering the advantages of hydrogen energy storage in large-scale, cross-seasonal and cross-regional aspects, the necessity, feasibility and economy of hydrogen energy participation in long-time energy storage under the new power system are discussed.
  • 695
  • 06 Jul 2023
Topic Review
Enabling Technologies for Power System Stability Enhancement
The growing attention to environmental issues is leading to an increasing integration of renewable energy sources into electrical grids. This integration process could contribute to power system decarbonization, supporting the diversification of primary energy sources and enhancing the security of energy supply, which is threatened by the uncertain costs of conventional energy sources. Despite these environmental and economical benefits, many technological and regulatory problems should be fixed in order to significantly increase the level of penetration of renewable power generators, which are connected to power transmission and distribution systems via power electronic interfaces. Indeed, these converter-interfaced generators (CIGs) perturb grid operation, especially those fueled by non-programmable energy sources (e.g., wind and solar generators), affecting the system stability and making power systems more vulnerable to dynamic perturbations. To face these issues, the conventional operating procedures based on pre-defined system conditions, which are currently adopted in power system operation tools, should be enhanced in order to allow the “online” solution of complex decision-making problems, providing power system operators with the necessary measures and alerts to promptly adjust the system. A comprehensive analysis of the most promising research directions and the main enabling technologies for addressing this complex issue is presented here.
  • 694
  • 09 Nov 2022
Topic Review
Photovoltaic Integration with the Saudi Electricity Grid
Due to uncertain photovoltaic (PV) power generation, analyzing the voltage stability of transmission networks with a large PV plant is challenging. The stability of PV output power is a critical factor in establishing PV penetration levels in active transmission networks when assessing loading capabilities. 
  • 694
  • 29 Feb 2024
Topic Review
Voltage-Source-Converter-Based High Voltage Direct Current Transmission System
Long-distance offshore wind power transmission systems utilize multi-terminal high voltage direct current (MT-HVDC) connections based on voltage source converters (VSCs). In addition to having the potential to work around restrictions, the VSC-based MT-HVDC transmission system has significant technical and economic merits over the HVAC transmission system. Offshore wind farms (OWFs) will inevitably grow because of their outstanding resistance to climate change and ability to provide sustainable energy without producing hazardous waste. Due to stronger and more persistent sea winds, the OWF often has a higher generation capacity with less negative climate effects. The majority of modern installations are distant from the shore and produce more power than the early OWF sites, which are situated close to the shore. 
  • 693
  • 20 Nov 2023
Topic Review
Problem Domains in Energy-Efficient and Load Balanced WSNs
Researchers are facing significant challenges to develop robust energy-efficient clustering and routing protocols for Wireless Sensor Networks (WSNs) in different areas such as military, agriculture, education, industry, environmental monitoring, etc. WSNs have made an everlasting imprint on everyone’s lives. Wireless Sensor Networks (WSN) can detect, store, and transmit data in real-time. These tasks must be completed efficiently to avoid wasting the limited sensor battery life. 
  • 692
  • 24 May 2022
Topic Review
Small-Signal Stability in Microgrid
The microgrid (MG) system is a controlled and supervised power system consisting of renewable energy (RE)-based distributed generation (DG) units, loads, and energy storage. The MG can be operated autonomously or while connected to the grid. Higher intermittencies and uncertainties can be observed in MGs compared to the conventional power system, which is the possible source of small-signal stability in MG systems. It can be seen as disturbances around the stable operating point, which potentially lead to the small-signal instability problem within MGs. Small-signal instability issues also emerge due to the lack of damping torque in the MG. The integration of power electronic devices and complex control algorithms within MGs introduces novel challenges in terms of small-signal stability and possible resonances. The occurrence of interaction in a low- or no-inertia system might worsen the stability margin, leading to undamped oscillatory instability. The interaction within the MG is characterized by various frequency ranges, from low-frequency subsynchronous oscillation to high-frequency ranges around the harmonic frequencies.
  • 690
  • 23 Apr 2023
Topic Review
Internet of Things-Based Control of Induction Machines
The Internet of Things (IoT) is introduced in systems with electrical machines, such as in electric drive systems, wind energy generating systems, and small and special machines, to remote monitor and control the operation for data acquisition and analysis. These systems can integrate with the equipment and retrofit the existing installations. At the end of the control loops there are always motors, or actuators, of big or small ratings, of rotating or linear movements, electrical or nonelectrical, which must produce the motion. With the IoT-based control of induction machine systems operators can remotely monitor parameters and obtain accurate real-time feedback during fast changing duty cycle operation. Thus, IoT creates multipurpose instruments in the remote control of induction machines. 
  • 688
  • 19 Feb 2024
Topic Review
Multiport Single Element Mimo Antenna Systems
In response to the increasing demand for voice, data, and multimedia applications, the next generation of wireless communication systems is projected to provide faster data rates and better service quality to customers. Techniques such as Multiple-Input–Multiple-Output (MIMO) and diversity are being studied and implemented to meet the needs of next-generation wireless communication systems. Embedding multiple antennas into the same antenna system is seen as a promising solution, which can improve both the system’s channel capacity and the communication link’s quality. For small handheld and portable devices, embedding many antennas into a single device in a small area and at the same time providing good isolation becomes a challenge.
  • 687
  • 19 Jan 2023
Topic Review
IoT-Based Hybrid AC/DC RES Environment
Smart microgrids, as the foundations of the future smart grid, combine distinct Internet of Things (IoT) designs and technologies for applications that are designed to create, regulate, monitor, and protect the microgrid (MG), particularly as the IoT develops and evolves on a daily basis. Communication networks are critical components of HRES because they allow data to flow between data sources (sensors and meters), control centers, and controllers. The data flow from various elements establishes the system architecture in addition to facilitating the control operation and remote monitoring. Sensing, communication, processing, and actuation will all benefit from IoT technology, which will facilitate a variety of MG applications.
  • 686
  • 08 Oct 2022
Topic Review
Wide-Bandgap Semiconductors Evaluation for High-Performance Domestic Induction Heating
In the induction heating system, the power transferred to the output depends on the equivalent resistance of the load, and the resistance depends on the operating frequency. Due to the switching characteristics of wide-bandgap power semiconductor devices, an induction heating system can be operated at higher operating frequencies.
  • 686
  • 25 May 2023
Topic Review
Physiological Computing in Human–Robot Collaboration
Human–robot collaboration has emerged as a prominent research topic. To enhance collaboration and ensure safety between humans and robots, researchers employ a variety of methods. One such method is physiological computing, which aims to estimate a human’s psycho-physiological state by measuring various physiological signals such as galvanic skin response (GSR), electrocardiograph (ECG), heart rate variability (HRV), and electroencephalogram (EEG). This information is then used to provide feedback to the robot.
  • 684
  • 15 Jun 2023
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