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Topic Review
Solid State Transformers in Distribution System
Solid State Transformer (SST) is considered to be the most suitable and appropriate conversion device to replace the traditional prevailing transformer. In this device, the weight/volume savings, extensive efficiency enhancement and above all, the cost economization are taken to be the hallmarks. SST configuration comprises of three main stages (i.e., a rectifier, isolation through the HF transformer and finally the DC-AC converter to reproduce line frequency AC).
  • 1.6K
  • 01 Dec 2022
Topic Review
Brake-by-Wire System
With the rapid development of electric vehicles (EVs) in the direction of advanced driving assistance systems and autonomous vehicles, the demands for X-by-wire systems are huge. For example, the brake-by-wire (BBW) system must have a fast enough step response, the adjustable ability of higher accuracy and fault tolerance to ensure the safety of vehicles. The BBW system of “safety, comfort, and low carbon” has become a troublesome issue in the development of the industry. In EVs, the moving parts that can achieve automatic control are more than 200. As an important assurance system for the safe driving of vehicles, the BBW system has the advantages of accurately and independently controlling the pressure of each wheel cylinder and a fast response. 
  • 1.6K
  • 26 Apr 2022
Topic Review
IoT-Enabled Smart Cities
Smart cities have been significantly developed and have greatly expanded their potential. In fact, novel advancements to the Internet of things (IoT) have paved the way for new possibilities, representing a set of key enabling technologies for smart cities and allowing the production and automation of innovative services and advanced applications for the different city stakeholders. 
  • 1.6K
  • 21 Feb 2022
Topic Review
Active Aerodynamic Systems for Road Vehicles
Comfort, safety, high travel speeds, and low fuel consumption are expected characteristics of modern cars. Some of these are in conflict with one other. A solution to this conflict may be time-varying body geometry realized by moving aerodynamic elements and appropriate systems for controlling their motion. 
  • 1.6K
  • 08 Apr 2022
Topic Review
General Performance of Pressure Wave Supercharger
One main direction in improving the efficiency of an internal combustion engine, together with lowering the emissions, is supercharging, i.e., creating a considerable amount of boost for the inlet combustion air. Turbochargers are the most commonly used for this task, but another advantageous alternative exploiting the energy within exhaust gases is the pressure wave supercharger (PWS).
  • 1.6K
  • 21 Apr 2022
Topic Review
Road Infrastructure Maintenance Management
Management of nonurban road network maintenance is a complex management process that requires the inclusion of many technical, economic, and other characteristics of the problem, as well as the continuous application of new knowledge and approaches, to maintenance management. To effectively manage the maintenance of the road network in conditions of limited financial resources, maintenance is examined through three interrelated management functions of planning: implementation, monitoring, and maintenance control. 
  • 1.6K
  • 20 Jun 2022
Topic Review
Functional Near-Infrared Spectroscopy
Sensor-level human brain activity is studied during real and imaginary motor execution using functional near-infrared spectroscopy (fNIRS). Blood oxygenation and deoxygenation spatial dynamics exhibit pronounced hemispheric lateralization when performing motor tasks with the left and right hands. This fact allowed us to reveal biomarkers of hemodynamical response of the motor cortex on the motor execution, and use them for designing a sensing method for classification of the type of movement. The recognition accuracy of real movements is close to 100%, while the classification accuracy of imaginary movements is lower but quite high (at the level of 90%). The advantage of the proposed method is its ability to classify real and imaginary movements with sufficiently high efficiency without the need for recalculating parameters. The proposed system can serve as a sensor of motor activity to be used for neurorehabilitation after severe brain injuries, including traumas and strokes.
  • 1.6K
  • 30 Oct 2020
Topic Review
CMOS Amplifiers
CMOS amplifiers are ubiquitous analog circuits which are used in computers, audio systems, smart phones, cameras, telecommunication systems, biomedical circuits and many other systems, and their performance has great impact on the overall specifications of the systems. They take their name from the use of MOSFET (Metal Oxide Semiconductor Field Effect Transistor) as opposite to Bipolar Junction Transistors (BJT). MOSFETS are simpler to fabricate and therefore less expensive than BJT amplifiers, still providing a sufficiently high transconductance to allow the design of very high performance circuits. In high performance CMOS amplifier circuits, transistors are not only used to amplify the signal but are also used as active loads to achieve higher gain and output swing in comparison with resistive loads. CMOS technology had been primarily introduced to design digital circuits. In the last decades, in order to improve speed, power consumption, required area and other aspects of digital integrated circuits (ICs), the feature size of MOSFET transistors has shrunk (minimum channel length of transistors reduces in newer CMOS technologies). This phenomenon predicted by Gordon Moore in 1975, which is called Moore’s law, and states that in about each 2 years, the number of transistors doubles for the same silicon area of ICs. Progress in memory circuits design is an interesting example to see how process advancement have affected the required size and their performance in the last decades. In 1956, a 5MB Hard Disk Drive (HDD) weighted over a tone, while these days having 50000 times more capacity with a weight of several tens of grams is very common. While digital ICs have enormously benefited from the feature size shrinking, analog CMOS amplifiers have not gained corresponding advantages due to the intrinsic limitations imposed by an analog design, like the intrinsic gain reduction of short channel transistors which affects the overall gain of amplifier. Novel techniques to achieve higher gain also create new problems, like stability of amplifier for closed-loop applications. In the following, we will address both aspects and summarize few different methods to overcome these problems.
  • 1.6K
  • 07 Nov 2022
Topic Review
Virtual Power Plant Optimization in Smart Grids
Virtual power plants (VPPs) are promising solutions to address the decarbonization and energy efficiency goals in the smart energy grid. They assume the coordination of local energy resources such as energy generation, storage, and consumption. They are used to tackle problems brought by the stochastic nature of renewable energy, lack of energy storage devices, or insufficient local energy flexibility on the demand side. VPP modeling, management, and optimization are open to research problems that should consider, on one side, the local constraints in the operation of the energy resources and power flows and the energy grid’s sustainability objectives on the other side. There are multiple goals to create a VPP, such as to deliver energy services on a market or to the grid operator, to operate a microgrid in autonomy decoupled from the main grid, or to sustain local energy communities. 
  • 1.6K
  • 27 May 2022
Topic Review
Graphene-based Membranes for H2 Separation
Hydrogen is an industrial gas that has showcased its importance in several well-known processes such as ammonia, methanol and steel productions, as well as in petrochemical industries. Besides, there is a growing interest in hydrogen production and purification owing to the global efforts to minimize the emission of greenhouse gases. Nevertheless, hydrogen which is produced synthetically is expected to contain other impurities and unreacted substituents (e.g., carbon dioxide, nitrogen and methane), such that subsequent purification steps are typically required for practical applications. In this context, membrane-based separation has attracted a vast amount of interest due to its desirable advantages over conventional separation processes, such as the ease of operation, low energy consumption and small plant footprint. Efforts have also been made for the development of high-performance membranes that can overcome the limitations of conventional polymer membranes. In particular, the studies on graphene-based membranes have been actively conducted most recently, showcasing outstanding hydrogen-separation performances.
  • 1.6K
  • 26 Nov 2020
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