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Topic Review
Flexible Electronics
Flexible electronics is a rapidly growing technology for a multitude of applications. Wearables and flexible displays are some application examples.
  • 2.7K
  • 28 Jan 2021
Topic Review
Frequency Multipliers for Terahertz Remote Sensing System
Terahertz (THz) electromagnetic waves have frequencies in the range of 0.1 THz to 10 THz, with corresponding wavelengths of 3 mm to 30 μm. This frequency range is adjacent to millimeter-wave electromagnetic frequencies and infrared light wavelengths, and is thereby associated with the engineering domain of both electromagnetics and photonics. Due to insufficient development and utilization, this frequency is often referred to as a “terahertz gap”. Terahertz-wave technologies have unique properties that include a large-magnitude skin depth, good directivity, wide bandwidth and high imaging resolution. Therefore, terahertz-wave technologies possess an unparalleled advantage for remote sensing applications.
  • 2.6K
  • 07 Jun 2022
Topic Review
Electric Vehicle Charging Systems
The high-voltage battery is a crucial element for electric vehicles (EVs) traction systems. It is the primary energy source that must be regularly recharged to reach the autonomy declared by the manufacturer. Therefore, an EV charging system is required to ensure the battery charging process. 
  • 2.6K
  • 27 Feb 2023
Topic Review
Abnormal Operating Conditions of Oil-Immersed Large Power Transformers
Large power transformers (LPT) are custom-built pieces of equipment that are crucial links to the bulk transmission grid. Usually, they link a generator-transmission line and/or linking lines of different voltages. It is essential for large power transformers to understand which condition of their components indicates an abnormal operation.
  • 2.6K
  • 12 Jul 2022
Topic Review
Pentacene
Pentacene is a polycyclic aromatic hydrocarbon consisting of five linearly-fused benzene rings. This highly conjugated compound is an organic semiconductor. The compound generates excitons upon absorption of ultra-violet (UV) or visible light; this makes it very sensitive to oxidation. For this reason, this compound, which is a purple powder, slowly degrades upon exposure to air and light. Structurally, pentacene is one of the linear acenes, the previous one being tetracene (four fused benzene rings) and the next one being hexacene (six fused benzene rings). In August 2009, a group of researchers from IBM published experimental results of imaging a single molecule of pentacene using an atomic force microscope. In July 2011, they used a modification of scanning tunneling microscopy to experimentally determine the shapes of the highest occupied and lowest unoccupied molecular orbitals. In 2012, pentacene-doped p-terphenyl was shown to be effective as the amplifier medium for a room-temperature maser.
  • 2.6K
  • 12 Oct 2022
Topic Review
Paper-Based Sensors Application
Paper-based sensors are getting increasing attention for reliable indoor/outdoor onsite detection with non-expert operation due to low cost, portability, easy disposal, and high accuracy, as well as bulky reduced laboratory equipment. They have become powerful analysis tools in trace detection with ultra-low detection limits and extremely high accuracy, resulting in their great popularity in biological detection, environmental inspection, and other applications. However, the current paper-based sensors still encounter insufficiencies such as harsh storage, short shelf time, singleplex analyte detection, disability of holographic strain detection, and low reproducibility for direct detection of the actual sample without pretreatment. Efforts should be made to paper-based sensors with those concerns before their broad commercial application. 
  • 2.6K
  • 22 Sep 2021
Topic Review
Avalanche Photodiodes and Silicon Photomultipliers of Non-Planar Designs
Conventional designs of an avalanche photodiode (APD) have been based on a planar p–n junction since the 1960s. APD developments have been driven by the necessity to provide a uniform electric field over the active junction area and to prevent edge breakdown by special measures. Most modern silicon photomultipliers (SiPM) are designed as an array of Geiger-mode APD cells based on planar p–n junctions. Modern Silicon Photomultipliers (SiPM) are designed as an array of Geiger-mode APD cells based on planar p-n junctions. However, the planar design faces an inherent trade-off between photon detection efficiency and dynamic range due to loss of an active area at the cell edges. Non-planar designs of APDs and SiPMs have also been known since the development of spherical APD (1968), Metal-Resistor-Semiconductor APD (1989), and Micro-well APD (2005). Recent development of Tip Avalanche Photodiode (2020) based on the spherical p-n junction eliminates the trade-off, outperforms the planar SiPMs in the photon detection efficiency, and opens new opportunities for SiPM improvements. Moreover, the latest developments of APDs based on electric field-line crowding and charge-focusing topology with quasi-spherical p-n junctions (2019–2023) show promising functionality in linear and Geiger operating modes.
  • 2.6K
  • 27 Jun 2023
Topic Review
Covariance Projection Filter
Consider n data sources with their data represented, respectively, by N1, N2,...,Nn dimensional vectors, such that   . The covariance projection framework of data fusion, or, shortly, the covariance projection filter (CPF), is based on projecting the joint probability distribution of those N0 variables from n data sources onto the constraint manifold formed in the N0 dimensional space, referred to here as the extended space, based on the constraints present among the N variables. Then, the covariance projection framework of data fusion represents the projected probability distribution on the constraint manifold as the result of data fusion. For instance, in CPF, the fused data can be chosen as the point on the constraint manifold that bears the maximum probability, while the uncertainty associated with the resulting fused data can be defined as the probability distribution around the chosen point on the constraint manifold. The covariance projection framework of data fusion was initially conceived by Sukhan Lee and further elaborated into a more formal mathematical discipline by Sukhan Lee and Muhammad Abu Bakr. It turns out that CPF is equivalent to other well-known data fusion methods such as Kalman filter, Bar Shalom Campo and generalized Millman’s formula for linear systems with known Gaussian noise either uncorrelated or correlated. However, CPF provides a general framework of data fusion that allows incorporation of any system constraints as well as detection of data inconsistency directly into data fusion, besides opening a new possibility of handling non-linear systems with non-Gaussian noise. In what follows, the mathematical formula of CPF developed, in particular, for a linear Gaussian system with linear constraint is introduced.
  • 2.5K
  • 01 Nov 2020
Topic Review
Pianet
The Pianet is a type of electro-mechanical piano built by the Hohner company of Trossingen, West Germany, from the early 1960s to the early 1980s. The designer of the early Pianet models was Ernst Zacharias, basing the mechanism closely on a 1920s design by Lloyd Loar. The Pianet was a variant of the earlier reed-based Hohner electric piano the Cembalet which, like the Pianet, was intended for home use. Hohner offered both keyboards in their range until the early 1970s. The Pianet production consisted of two distinctly different mechanism groups with characteristically different sound. The first group, lasting from introduction to 1977, had ground stainless steel reeds, a pick-up using variable capacitance, and leather faced activation pads. The second group from 1977 until the end of production used rolled spring-steel reeds, electro-magnetic pick-ups, and moulded silicone rubber activation pads.
  • 2.5K
  • 21 Oct 2022
Topic Review
Fundamentals of Coupled Bulk Acoustic Wave MEMS Resonators
Bulk acoustic wave (BAW) resonators are a type of Micro-Electro-Mechanical System (MEMS) device experiencing acoustic wave propagation through the bulk of the medium. Combining the approach of coupled resonators with BAW resonators has recently led to achieving better performance and new functionalities. In particular, coupled BAW resonators based on lateral vibration modes are studied due to its advantages.
  • 2.5K
  • 06 Jun 2022
Topic Review
Torque Ripple Reduction Design Methods
There are some phenomena that affect electric vehicle performance. One of those phenomena is the torque ripple of electric motors, which interferes with traction and the suspension system (causing vibration that stresses this system), and it can also introduce electric current harmonics into the battery, reducing its life, since torque ripple is partly a consequence of non-sinusoidal back EMF. For those reasons this is a topic worth investigating. The torque ripple of permanent magnets (PM) motors can be reduced in design or through control.
  • 2.5K
  • 15 Dec 2022
Topic Review
Electromagnetic Vibrational Energy Harvesting Principles
As industries need more real-time monitoring and interconnected systems, the demand for wireless sensors expands. Vibrational energy harvesters are a potential solution for powering these sensors, as vibrations commonly exist where monitoring occurs. Developments in low-power circuitry have also led to the feasibility of these types of harvesters. Electromagnetic harvesters are a standout among various types of vibrational harvesters due to their ability to capture kinetic energy in a low-frequency range. This leads to these devices being more applicable in real-world applications where ambient vibrations are typical of having low frequencies.
  • 2.5K
  • 04 Aug 2022
Topic Review
Electric Powertrain Architectures in Off-Road Equipment
Though the wave of electric vehicles is transforming the on-road passenger and commercial vehicle fleets, similar attempts in the off-road equipment sector appear to be lacking. Because of the diverse equipment categories and varied applications, electrifying off-road equipment requires significant research and development.
  • 2.5K
  • 26 Aug 2022
Topic Review
Electricity Demand Forecasting
With the globally increasing electricity demand, its related uncertainties are on the rise as well. Therefore, a deeper insight into load forecasting techniques for projecting future electricity demands becomes imperative for business entities and policymakers. The electricity demand is governed by a set of different variables or “electricity demand determinants”. These demand determinants depend on forecasting horizons (long term, medium term, and short term), the load aggregation level, climate, and socio-economic activities. In this paper, a review of different electricity demand forecasting methodologies is provided in the context of a group of low and middle-income countries. The article presents a comprehensive literature review by tabulating the di fferent demand determinants used in di fferent countries and forecasting the trends and techniques used in these countries. A comparative review of these forecasting methodologies over di fferent time horizons reveal that the time series modeling approach has been extensively used while forecasting for long and medium terms. For short term forecasts, artificial intelligence-based techniques remain prevalent in the literature. Furthermore, a comparative analysis of the demand determinants in these countries indicates frequent use of determinants like the population, GDP, weather, and load data over di fferent time horizons.
  • 2.5K
  • 05 Aug 2020
Topic Review
Power Electronics and Battery Cooling Methods
The global promotion of electric vehicles (EVs) through various incentives has led to a significant increase in their sales. The prolonged charging duration remains a significant hindrance to the widespread adoption of these vehicles and the broader electrification of transportation. While DC-fast chargers have the potential to significantly reduce charging time, they also result in high power demands that the grid and hence may require local battery energy storage systems (BESS) for peak shaving applications. A high power demand also creates high losses and cooling methods play an important role in overall efficiency, sound pollution, system size, reliability, and lifetime of the system.  
  • 2.5K
  • 27 Feb 2023
Topic Review
Current Virtual Inertia Topologies
The use of power electronic inverters leads to the dissociation of sources and loads and lowering the power system inertia. Under power imbalance, this drop causes an elevated rate of change in frequency and frequency divergences, which has a notable impact on the system’s frequency stability. As a result, enhanced control techniques for grid-tied electronic converters are required to secure the power system’s stability and support. The virtual-synchronous generator (VSG) control is used to mimic the dynamics of a rotating synchronous generator and improve the power system’s stability.
  • 2.5K
  • 30 Nov 2022
Topic Review
Intrusion Detection System for SOME/IP-Based In-Vehicle Network
This research describes a hybrid AI and rule-based intrusion detection system for detecting SOME/IP communication threats in new automotive electronic electrical architectures.
  • 2.4K
  • 24 May 2023
Topic Review
Optimization Approaches for Microgrid Energy Management
The microgrids (MG) is a single controllable local power network with distributed energy sources (solar Photovoltaics (PV), wind energy, diesel generator, fuel cell, wave energy, etc.), ESS, controllable distributed loads (households, commercial, industrial, etc.), and advanced energy management systems (EMSs). It can be operated alone or in connection with the utility grid. 
  • 2.4K
  • 07 Dec 2022
Topic Review
Smart City Assessment Tools
Today's cities are estimated to generate 80% of global GDP, covering only about 3% of the land, but contributing to about 72% of all global greenhouse gas emissions. Cities face significant challenges, such as population growth, pollution, congestion, lack of physical and social infrastructures, while trying to simultaneously meet sustainable energy and environmental requirements. The Smart City concept intends to address these challenges by identifying new and intelligent ways to manage the complexity of urban living and implement solutions for multidisciplinary problems in cities. With the increasing number of Smart City projects being implemented around the world, it is important to evaluate their strengths and weaknesses for their future improvement and evolution track record.
  • 2.4K
  • 09 Dec 2021
Topic Review
Haptic Devices Designed for Hearing-Impaired People
Haptic devices transmit information to the user, using tactile stimuli to augment or replace sensory input. People with limited sensory abilities, such as vision or hearing can receive supplementary information by relying on them.
  • 2.4K
  • 31 Mar 2023
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