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Topic Review
Piezoelectric MEMS Laterally Vibrating Resonators
Piezoelectric MEMS Laterally Vibrating Resonators (LVRs), which belong to one type of micromachined resonators that uses piezoelectric transduction, are characterized by dominant mechanical vibration in the lateral direction (within the plane of the device). In piezoelectric MEMS LVRs, the electric field is mainly applied across the thickness of the piezoelectric film to generate a lateral strain within the plane of the device with suspended free edges. Due to the lithographically definable resonant frequency, piezoelectric LVRs feature wide operation frequency coverage (from tens of MHz to several GHz) and provide a pathway towards realizing a multi-frequency integrated solution on a single chip. Depending on the structure of resonators, piezoelectric MEMS LVRs can be categorized into two types. The first type of LVRs consists of a piezoelectric film, both as the transducer and acoustic cavity. The second type of LVRs uses the thin piezoelectric film as a transducer only while having most of the acoustic energy propagating in the underlying thicker substrate. Such resonators are usually referred to as thin-film piezoelectric-on-substrate (TPoS) resonators. Typical applications of piezoelectric MEMS LVRs include resonant sensors, oscillators and RF filters.
  • 1.7K
  • 14 Sep 2020
Topic Review
Energy Management and Control Techniques for Electric Vehicle
Electric vehicles (EVs) are universally recognized as an incredibly effective method of lowering gas emissions and dependence on oil for transportation. Electricity, rather than more traditional fuels like gasoline or diesel, is used as the main source of energy to recharge the batteries in EVs. Future oil demand should decline as a result of the predicted rise in the number of EVs on the road. The charging infrastructure is considered as a key element of EV technology where the recent research is mostly focused. A strong charging infrastructure that serves both urban and rural areas, especially those with an unstable or nonexistent electrical supply, is essential in promoting the global adoption of EVs.
  • 1.7K
  • 10 Aug 2023
Topic Review
Facial Expression Recognition
Facial expression recognition (FER) is a challenging problem in the fields of pattern recognition and computer vision. The recent success of convolutional neural networks (CNNs) in object detection and object segmentation tasks has shown promise in building an automatic deep CNN-based FER model. However, in real-world scenarios, performance degrades dramatically owing to the great diversity of factors unrelated to facial expressions, and due to a lack of training data plus an intrinsic imbalance in the existing facial emotion datasets. To tackle these problems, this paper not only applies deep transfer learning techniques but also proposes a novel loss function called weighted-cluster loss, which is used during the fine-tuning phase. Specifically, the weighted-cluster loss function simultaneously improves the intra-class compactness and the inter-class separability by learning a class center for each emotion class. It also takes the imbalance in a facial expression dataset into account by giving each emotion class a weight based on its proportion of the total number of images. In addition, a recent, successful deep CNN architecture, pre-trained in the task of face identification with the VGGFace2 database from the Visual Geometry Group at Oxford University, is employed and fine-tuned using the proposed loss function to recognize eight basic facial emotions from the AffectNet database of facial expression, valence, and arousal computing in the wild. Experiments on an AffectNet real-world facial dataset demonstrate that our method outperforms the baseline CNN models that use either weighted-softmax loss or center loss.
  • 1.7K
  • 09 Feb 2021
Topic Review
TI MSP432
The MSP432 is a mixed-signal microcontroller family from Texas Instruments. It is based on a 32-bit ARM Cortex-M4F CPU, and extends their 16-bit MSP430 line, with a larger address space for code and data, and faster integer and floating point calculation than the MSP430. Like the MSP430, it has a number of built-in peripheral devices, and is designed for low power requirements.
  • 1.7K
  • 04 Nov 2022
Topic Review
Modeling and Control of Piezoelectric Actuators
Piezoelectric actuators find extensive application in delivering precision motion in the micrometer to nanometer range. The advantages of a broader range of motion, rapid response, higher stiffness, and large actuation force from piezoelectric actuators make them suitable for precision positioning applications. However, the inherent nonlinearity in the piezoelectric actuators under dynamic working conditions severely affects the accuracy of the generated motion. The nonlinearity in the piezoelectric actuators arises from hysteresis, creep, and vibration, which affect the performance of the piezoelectric actuator. Thus, there is a need for appropriate modeling and control approaches for piezoelectric actuators, which can model the nonlinearity phenomenon and provide adequate compensation to achieve higher motion accuracy. 
  • 1.6K
  • 15 Dec 2023
Topic Review
Piezoelectric Rotary Harvesters
Technologies of energy harvesting have been developed intensively since the beginning of the twenty-first century, presenting themselves as alternatives to traditional energy sources (for instance, batteries) for small-dimensional and low-power electronics. Batteries have numerous shortcomings connected, for example, with restricted service life and the necessity of periodic recharging/replacement that create significant problems for portative and remote devices and for power equipment. Environmental energy covers solar, thermal, and oscillation energy. By this, the vibration energy exists continuously around us due to the operation of numerous artificial structures and mechanisms. Different materials (including piezoelectrics) and conversion mechanisms can transform oscillation energy into electrical energy for use in many devices of energy harvesting. Piezoelectric transducers possessing electric mechanical coupling and demonstrating a high density of power in comparison with electromagnetic and electrostatic sensors are broadly applied for the generation of energy from different oscillation energy sources.
  • 1.6K
  • 14 Apr 2022
Topic Review
Non-Resonant Single-Wire Power Transmission Systems
A single-wire power transmission is an option for reducing the capital cost of power line construction by utilizing fewer conductors and fittings and lighter power transmission towers while lowering operational expenses.
  • 1.6K
  • 31 Jul 2023
Topic Review
Interfaces in State-of-the-Art Cable Connectors
One of the most important causes of insulation system failure is the breakdown of the interface between two solid dielectrics; understanding the mechanisms governing this breakdown phenomenon is therefore critical. Solid–solid interfaces in accessories have non-uniform distributions of electrical fields within them in comparison to cables, where the distribution is mostly radial and symmetrical.
  • 1.6K
  • 07 Dec 2021
Topic Review
Theoretical Framework of Thermoelectric Generation
The world’s growing energy demand poses several concerns regarding the rational and efficient use of energy resources. This is also the case for many industrial processes, where energy losses and particularly thermal losses are common. Thermoelectric generators offer an alternative to address some of these challenges by recovering wasted heat and thereby increasing the overall efficiency of these processes. The successful operation of the thermoelectrical modules meant to carry this process is only possible when pairing these to an external control system; such a system plays an important role in predicting and operating such modules at its maximum power point.
  • 1.6K
  • 20 Jan 2023
Topic Review
Takagi–Sugeno Fuzzy-PI Controller Hardware
The intelligent system Field Programmable Gate Array (FPGA) is represented as Takagi--Sugeno Fuzzy-PI controller. The implementation uses a fully parallel strategy associated with a hybrid bit format scheme (fixed-point and floating-point). Two hardware designs are proposed; the first one uses a single clock cycle processing architecture, and the other uses a pipeline scheme. The bit accuracy was tested by simulation with a nonlinear control system of a robotic manipulator. The area, throughput, and dynamic power consumption of the implemented hardware are used to validate and compare the results of this proposal. The results achieved allow the use of the proposed hardware in applications with high-throughput, low-power, and ultra-low-latency requirements such as teleoperation of robot manipulators, tactile internet, or industry 4.0 automation, among others.
  • 1.6K
  • 29 Oct 2020
Topic Review
Power Grid Infrastructures
This content presents a comprehensive review of protection systems with the penetration of microgrids in the distribution network. The expansion of a microgrid affects the coordination and protection by a change in the current direction in the distribution network. 
  • 1.6K
  • 01 Dec 2020
Topic Review
Swarm Robotics
Swarm robotics is a dynamic research field that integrates two important concepts: Swarm Intelligence (SI) and Multi-Robotics System (MRS).
  • 1.6K
  • 02 Jun 2022
Topic Review
5G Wearable Devices
One potential way of enhancing capacity and data rates in the current and future mobile and wireless generations is the bandwidth. The data rates are directly proportional to the bandwidth. The higher bandwidth provides higher data rates. However, current frequency bands, i.e., 1.7 GHz GSM band, 1.8 GHz 4G/LTE band, 2.0 GHz 4G/LTE band, 2.1 LTE band, and 2.6 GHz band, provide limited bandwidth. Recently, high-frequency bands including 24 GHz (n258), 28 GHz (n257 and n261), 37 GHz (n260), and 39 GHz (n260) in addition to some future recommended bands, i.e., 47 and 60 GHz, have been considered for 5G applications.
  • 1.6K
  • 11 Jan 2022
Topic Review
Apple Cinema Display
The Apple Cinema Display is a line of flat-panel computer monitors developed and sold by Apple Inc. between 1999 and 2011. It was initially sold alongside the older line of Studio Displays, but eventually replaced them. Apple offered 20-, 22-, 23-, 24-, 27- and 30-inch sizes, with the last model being a 27-inch size with LED backlighting. There have been three designs for the Cinema Display, one featuring polycarbonate plastic and two featuring anodized aluminum. The first displays were designed to match the colorful plastic of the Power Mac G3 and later the Power Mac G4, while the second revisions were designed to match the aluminum aesthetics of the Power Mac G5 and PowerBook G4. The last available design matched the unibody laptops released in October 2008. The Apple Cinema Display name was retired in July 2011 with the introduction of the Apple Thunderbolt Display, and the Cinema Display models were no longer offered on the Apple Store website as of August 2014.
  • 1.6K
  • 05 Dec 2022
Topic Review
Viewing Angle Switchable Liquid Crystal Devices
For pure liquid crystals (LCs) system, methods for switchable viewing angle devices are divided into hybrid aligned nematic (HAN) LC cells, double cells, pixel division and three-electrode structure. Utilizing 3M light-control film and PDLC film together to create switchable anti-peeping film, PDLC is a voltage-controlled LC film that can switch between transparent and scattering, light scattering intensity of PDLC film is dependent on electric field, switchable voltage between light scattering (share mode) and transparent state (privacy mode) is approximately 5.0 V.
  • 1.6K
  • 10 Oct 2022
Topic Review
Simulators in Educational Robotics
Simulators are part of educational robotics, which easily and quickly enable the user to engage virtually with the development and programming of robots through GUIs. Using a simulator means that it is not necessary to deal exclusively with real robots that might have a significant cost. Hence, simulators are a useful tool that might save resources and assist the educational process.
  • 1.6K
  • 18 Mar 2021
Topic Review
Electrical Contacts
An electrical contact is an electrical circuit component found in electrical switches, relays, connectors and circuit breakers. Each contact is a piece of electrically conductive material, typically metal. When a pair of contacts touch, they can pass an electrical current with a certain contact resistance, dependent on surface structure, surface chemistry and contact time; when the pair is separated by an insulating gap, then the pair does not pass a current. When the contacts touch, the switch is closed; when the contacts are separated, the switch is open. The gap must be an insulating medium, such as air, vacuum, oil, SF6. Contacts may be operated by humans in push-buttons and switches, by mechanical pressure in sensors or machine cams, and electromechanically in relays. The surfaces where contacts touch are usually composed of metals such as silver or gold alloys that have high electrical conductivity, wear resistance, oxidation resistance and other properties.
  • 1.6K
  • 04 Nov 2022
Topic Review
Electrically Excited Doubly Salient Variable Reluctance Machine
The Electrically Excited Doubly Salient Variable Reluctance Machine (EEDSVRM) is a new type of brushless machine designed according to the principle of air gap reluctance change.
  • 1.6K
  • 14 Jan 2022
Topic Review
Sensor Calibration
A sensor is a detection device that can convert measured data into electrical signals output according to certain rules in order to meet the requirements of information transmission, processing, storage, display, recording, and control. The performance indicators of sensors usually include sensitivity, resolution, linearity, repeatability, stability, accuracy, and so on. The process of experimentally determining, under predetermined measurement conditions, the correspondence between a sensor’s input and output is known as calibration. The sensor has to be recalibrated if any of its indicators have changed as a result of the external environment or if it has been some time since the last calibration. 
  • 1.6K
  • 28 Aug 2023
Topic Review
Color Coding Technology for Visualization
Color coding technology for data visualization Data visualization achieves its significance today due to information technology: big data processed in computers with capable visualization software, combined with statistical techniques and color coding on electronic displays. This article is about color coding technology for data visualization. Origins of color coding include rubrics, the Four Color Theorem of cartography and Jacques Bertin's 1967 book, The Semiology of Graphics. Contemporary color coding for data visualization is enabled by four technologies: statistics, color technology, displays and computing. Visualization of data was proceduralized by statisticians John Tukey and Edward Tufte in their respective landmark books Exploratory Data Analysis in 1977 and Visual Display of Quantitative Information in 1982. They did not emphasize the use of color. Others demonstrated the superiority of color coding to speed visual search of displayed information, and to locate and organize information of interest. A third prerequisite for color-coded data visualization is high-resolution, high-contrast, high-luminance color electronic displays. Honeywell Corporation and Boeing Corporation assembled technical data that are still germane to use of color displays. More recently, the US Federal Aviation Administration has published technical guidance for visualization of dynamic (air traffic) data on self-luminous color displays. Humans have an innate ability to perform color-coded visual search. Without training or practice, the search time with color coding can be reduced by a factor of ten or more, compared to a search of the same information display without color coding. 
  • 1.6K
  • 12 Oct 2022
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