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Topic Review
Human–Machine Relationship
The human–machine relationship was dictated by human needs and what technology was available at the time. Changes within this relationship are illustrated by successive industrial revolutions as well as changes in manufacturing paradigms.  
  • 2.2K
  • 22 Feb 2023
Topic Review
Permanent Magnet Machines for High-Speed Applications
High-speed electrical machines have been extensively researched in the last few decades for industrial and domestic applications, including compressors, vacuum pumps, turbine generators, machine tools, flywheel energy storages, and so on. Compared with low-speed and moderate-speed conventional electrical machines, high-speed electrical machines offer advantages such as high-power density, small size, and light weight. More importantly, high-speed electrical machines can be directly connected to high-speed loads, and conventional gear boxes are no longer needed, which avoids complex gear box systems, improves system efficiency and reliability, and reduces system vibration, noise, and cost. With the evolution in the field of power electronics converters, the problems of high frequency supplies, required for high-speed operation, is no longer a restriction. The development of high-speed electrical machines is also supported by the development of high-speed bearing systems with high robustness, fewer losses, and longer lifetime.
  • 2.2K
  • 17 Jan 2022
Topic Review
Hybrid Prognostic Approaches of Aircraft Systems and Components
Prognostic and health management (PHM) plays a vital role in ensuring the safety and reliability of aircraft systems. The process entails the proactive surveillance and evaluation of the state and functional effectiveness of crucial subsystems. The principal aim of PHM is to predict the remaining useful life (RUL) of subsystems and proactively mitigate future breakdowns in order to minimize consequences. The achievement of this objective is helped by employing predictive modeling techniques and doing real-time data analysis. The incorporation of prognostic methodologies is of utmost importance in the execution of condition-based maintenance (CBM), a strategic approach that emphasizes the prioritization of repairing components that have experienced quantifiable damage. Multiple methodologies are employed to support the advancement of prognostics for aviation systems, encompassing physics-based modeling, data-driven techniques, and hybrid prognosis. 
  • 2.2K
  • 10 Oct 2023
Topic Review
Xiaomi Redmi Note 4
The Xiaomi Redmi Note 4 is the fourth smartphone of Redmi Note series developed by Xiaomi Inc. It is a part of Xiaomi's budget Redmi smartphone line. It has two variants: The older version sold as Redmi Note 4 is powered by a Deca-core Mediatek MT6797 Helio X20 SOC. The upgraded version, sold both as Redmi Note 4X and Redmi Note 4 (where MTK version was not released) is powered by an Octa-core MSM8953 Qualcomm Snapdragon 625 SoC. The Redmi Note 4 was succeeded by Redmi Note 5.
  • 2.2K
  • 26 Oct 2022
Topic Review
Households Energy Consumption in Iran
This review tends to obtain a deeper understanding of the methods used in household energy consumption and carbon dioxide (CO2) emissions in Iran. Issues relating to energy consumption and CO2 emissions are very complex. This complexity arises from the fact that energy demand and energy consumption in Iran are influenced by many factors, such as income, household size, age, and gender. In Iran, the relevant energy sources mostly include liquefied petroleum gas (LPG) and electricity, which are used for different sectors, such as transportation, industry, and residential. This overview looks at both the theories and empirical studies of household energy consumption and CO2 emissions in Iran. Since energy consumption typically results in air pollution, it is often used as an indicator of environmental degradation. Although Iran is recently faced energy efficiency improvement from all sectors, household energy requirements have been significantly increased. In Iran, a prime motivator had been improving living standards. As Iran gradually turns into a consumer society, households have an enormous influence on the direct use of energy and related CO2 emissions as well as through indirect use, as embodied in goods and services. The findings of this study can help policymakers to focus on renewable energy projects in order to reduce energy consumption and mitigate CO2 emissions.
  • 2.2K
  • 25 Aug 2020
Topic Review
Evaluation of Externalities of Highway Infrastructures
Various externalities caused by highway infrastructures, such as promoting economic development, traffic congestion, and air pollution, are becoming more and more important. Currently, there is no multi-dimensional quantitative evaluation of the externalities of highway infrastructures, hindering the sustainable planning and development of highway infrastructures. A summary of the status of the evaluation of the externalities of highway infrastructures is from four perspectives: social evaluation, economic evaluation, ecological evaluation, and comprehensive evaluation.
  • 2.2K
  • 11 Mar 2022
Topic Review
Resonant cavity antennas technology
       Resonant cavity antennas (RCAs) are suitable candidates to achieve high directivity with a low-cost and easy fabrication process. The stable functionality of the RCAs over different frequency bands, as well as, their pattern reconfigurability make them an attractive antenna structure for the next-generation wireless communication systems, i.e., fifth-generation (5G). The variety of designs and analytical techniques regarding the main radiator and partially reflective surface (PRS) configurations allow dramatic progress and advances in the area of RCAs. Adding different functionalities in a single structure by using additional layers is one appealing feature of the RCA structures, which has opened the various fields of studies toward 5G applications. This paper reviews the recent advances on the RCAs along with the analytical methods, and various capabilities that make them suitable to be used in 5G communication systems. 
  • 2.2K
  • 27 Aug 2020
Topic Review
Impacts of Lighting on Psychology, Physiology, and Productivity
People spend almost 90% of their time in indoor environments. Indoor environment quality has begun to play a more important role in people’s daily lives. The impact on occupants of various environmental factors of buildings has been actively studied. Among them, lighting conditions have been shown to have a significant influence on all aspects of human life and health.
  • 2.2K
  • 30 Jun 2022
Topic Review
Grid-Forming Converters and Power System Stability
Historically, the power system has relied on synchronous generators (SGs) to provide inertia and maintain grid stability. However, because of the increased integration of power-electronics-interfaced renewable energy sources, the grid’s stability has been challenged in the last decade due to a lack of inertia. Currently, the system predominantly uses grid-following (GFL) converters, built on the assumption that inertial sources regulate the system stability. Such an assumption does not hold for the low-inertia grids of the future. Grid-forming (GFM) converters, which mimic the traditional synchronous machinery’s functionalities, have been identified as a potential solution to support the low-inertia grids. The performance analysis of GFM converters for small-signal instability can be found in the literature, but large-signal instability is still an open research question. Moreover, various topologies and configurations of GFM converters have been proposed. Still, no comparative study combining all GFC configurations from the perspective of large-signal stability issues can be found. This research combines and compares all the existing GFM control schemes from the perspective of large-signal stability issues to pave the way for future research and development of GFM converters for large-signal stability analysis and stabilization of the future low-inertia grids. 
  • 2.2K
  • 19 Jul 2022
Topic Review
Bombardier CRJ200
The Bombardier CRJ100 and CRJ200 (formerly known as the Canadair CRJ100 and CRJ200) are a family of regional airliners designed and manufactured by Bombardier. The CRJ had the distinction of marking Canada's entry into the civil jet industry. It was based on the Canadair Challenger business jet. An initial effort to produce an enlarged 36-seat version of the aircraft, known as the Challenger 610E, was terminated during 1981. Shortly after Canadair's privatisation and sale to Bombardier, work on a stretched derivative was reinvigorated; during early 1989, the Canadair Regional Jet program was formally launched. On 10 May 1991, the first of three CRJ100 prototypes conducted its maiden flight. The type first entered service during the following year with its launch customer, Germany airline Lufthansa. The initial variant, the CRJ100, was soon joined by another model, designated as the CRJ200. It was largely identical to the CRJ100, except for the installation of more efficient turbofan engines, which gave the aircraft lower fuel consumption, increased cruise altitude and cruise speed. During the 1990s, various additional versions and models of the type were developed and put into service. During the late 1990s, a substantially enlarged derivative of the airliner, referred to as the CRJ700, was developed; it was soon joined by the even larger CRJ900 and CRJ1000. During 2006, production of both the CRJ100 and CRJ200 came to an end; the majority of produced airliners have remained in revenue service to date. Additionally, several airlines have modernised their fleets to support extended service.
  • 2.2K
  • 27 Oct 2022
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