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Topic Review
Street Canyon
A street canyon (also known as an urban canyon) is a place where the street is flanked by buildings on both sides creating a canyon-like environment. Classic examples of these human-built canyons are made when streets separate dense blocks of structures, especially skyscrapers. These include the Magnificent Mile in Chicago, Toronto's Financial District, the Canyon of Heroes in Manhattan and Hong Kong's Kowloon and Central districts. Urban canyons affect various local conditions, including temperature, wind, air quality, and radio reception, including satellite navigation signals.
  • 1.6K
  • 26 Oct 2022
Topic Review
Side Lobe
In antenna engineering, side lobes or sidelobes are the lobes (local maxima) of the far field radiation pattern of an antenna or other radiation source, that are not the main lobe. The radiation pattern of most antennas shows a pattern of "lobes" at various angles, directions where the radiated signal strength reaches a maximum, separated by "nulls", angles at which the radiated signal strength falls to zero. This can be viewed as the diffraction pattern of the antenna. In a directional antenna in which the objective is to emit the radio waves in one direction, the lobe in that direction is designed to have a larger field strength than the others; this is the "main lobe". The other lobes are called "side lobes", and usually represent unwanted radiation in undesired directions. The side lobe directly behind the main lobe is called the back lobe. The longer the antenna relative to the radio wavelength, the more lobes its radiation pattern has. In transmitting antennas, excessive side lobe radiation wastes energy and may cause interference to other equipment. Another disadvantage is that confidential information may be picked up by unintended receivers. In receiving antennas, side lobes may pick up interfering signals, and increase the noise level in the receiver. The power density in the side lobes is generally much less than that in the main beam. It is generally desirable to minimize the sidelobe level (SLL), which is measured in decibels relative to the peak of the main beam. The main lobe and side lobes occur for both transmitting and receiving. The concepts of main and side lobes, radiation pattern, aperture shapes, and aperture weighting, apply to optics (another branch of electromagnetics) and in acoustics fields such as loudspeaker and sonar design, as well as antenna design. Because an antenna's far field radiation pattern is a Fourier Transform of its aperture distribution, most antennas will generally have sidelobes, unless the aperture distribution is a Gaussian, or if the antenna is so small as to have no sidelobes in the visible space. Larger antennas have narrower main beams, as well as narrower sidelobes. Hence, larger antennas have more sidelobes in the visible space (as the antenna size is increased, sidelobes move from the evanescent space to the visible space).
  • 1.6K
  • 28 Nov 2022
Topic Review
North–South Commuter Railway
The North–South Commuter Railway (NSCR), also known as the Clark–Calamba Railway, is a 148 km (92 mi) urban rail transit line being constructed in Luzon. It will run from New Clark City in Capas, Tarlac to Calamba, Laguna with 36 stations, with historic stations to be restored. Originally planned in the 1990s, the project has been repetitively halted after disagreements on funding and allegations of overpricing. The first proposal was the 32 km (20 mi) "Manila–Clark rapid railway" with Spain, and during the 2000s, the NorthRail project with China that was discontinued in 2011. The present line is under the Duterte administration and is to be aided with Japanese financing. It was initially reported to have a total length of 180 km (110 mi), though it was reduced to 148 kilometers (92 mi) after a segment to Los Baños was scrapped. The railway system is expected to cost ₱777.55 billion (US$14.95 billion), making it one of the most expensive projects of the Build! Build! Build! Infrastructure Program. Partial operations will begin by 2021, and full operations is expected to begin by 2025. The NSCR will comprise two sections corresponding to the Philippine National Railways' old main lines; the 91 km (57 mi) fully-elevated NSCR North which is being built over the mostly-defunct North Main Line in northern Metro Manila and Central Luzon, and the 56 km (35 mi) NSCR South which will use the existing PNR Metro Commuter Line infrastructure between Tutuban and Calamba, which were historically parts of the South Main Line and will have elevated, at-grade and depressed sections. The project's construction is divided into three phases with the NSCR North being separated between the 38 km (24 mi) NSCR North 1 commuter line between Tutuban and Malolos, and the 53 kilometres (33 mi) NSCR North 2 regional line from Malolos to New Clark City. It will also be linked to existing and future railway lines such as Line 8, Line 9, the Calamba–Bicol South Main Line and Calamba–Batangas City Railway.
  • 1.6K
  • 09 Oct 2022
Topic Review
Recent Trends in Copper Metallization
The Cu/low-k damascene process was introduced to alleviate the increase in the RC delay of Al/SiO2 interconnects, but now that the technology generation has reached 1× nm or lower, a number of limitations have become apparent. Due to the integration limit of low-k materials, the increase in the RC delay due to scaling can only be suppressed through metallization.
  • 1.6K
  • 28 Sep 2022
Topic Review
Sustainable Urban Mobility
Sustainable urban mobility is a term that refers to the use of means of transport that do not affect the environment and an approach to the planning of the development of urban areas with sustainability goals in mind. When creating sustainable urban mobility plans, planners must also have the number of inhabitants in urban areas in mind as well as the need to ensure a satisfactory transportation service for residents located in urban areas. In order to respond to the ever-increasing need to develop sustainable modes of transport, the importance of electric, autonomous, and electric autonomous vehicles is increasingly emphasized. In addition, as trends of growth and development in electric autonomous vehicle technology are increasing, one of the questions that has appeared is whether autonomous electric vehicles represent one of the mechanisms that will be used to increase the sustainability of urban mobility. 
  • 1.6K
  • 27 Sep 2022
Topic Review
Load Forecasting Models in Smart Grid
The smart grid concept is introduced to accelerate operational efficiency and enhance the reliability and sustainability of the power supply. The load forecasting technique involves estimating future loads using historical and present data. In a smart grid, the forecasting of loads is done by considering the power consumption by users and the power produced by all types of generations (renewable and non-renewable) with the help of smart energy meters.
  • 1.6K
  • 24 Feb 2023
Topic Review
Vertical Axis Wind Turbine
A vertical-axis wind turbines (VAWT) is a type of wind turbine where the main rotor shaft is set transverse to the wind (but not necessarily vertically) while the main components are located at the base of the turbine. This arrangement allows the generator and gearbox to be located close to the ground, facilitating service and repair. VAWTs do not need to be pointed into the wind, which removes the need for wind-sensing and orientation mechanisms. Major drawbacks for the early designs (Savonius, Darrieus and giromill) included the significant torque variation or "ripple" during each revolution, and the large bending moments on the blades. Later designs addressed the torque ripple issue by sweeping the blades helically (Gorlov type). A vertical axis wind turbine has its axis perpendicular to the wind streamlines and vertical to the ground. A more general term that includes this option is "transverse axis wind turbine" or "cross-flow wind turbine." For example, the original Darrieus patent, US Patent 1835018, includes both options. Drag-type VAWTs such as the Savonius rotor typically operate at lower tipspeed ratios than lift-based VAWTs such as Darrieus rotors and cycloturbines.
  • 1.6K
  • 20 Oct 2022
Biography
Benjamin Hick
Benjamin Hick (1 August 1790 – 9 September 1842) was a successful English civil and mechanical engineer, art collector and patron;[1] his improvements to the steam engine and invention of scientific tools were held in high esteem by the engineering profession,[2] some of Hick's improvements became public property without claiming the patent rights he was entitled to.[3] He was born at Hudder
  • 1.6K
  • 28 Nov 2022
Topic Review
Flexible Wearable Sensor
Sensors are the core of wearable monitoring equipment. In wearable devices (such as wrist strap or chest strap), the sensor will inevitably contact with the skin.
  • 1.6K
  • 27 Oct 2020
Topic Review
DNA-Based Biosensors
Due to superior biocompatibility, thermal stability, and alternative functionalization, deoxyribonucleic acid (DNA) is becoming a fascinating biological material used for biosensing. It is widely acknowledged that DNA and its assembly structure can be applied for detecting specific targets, including nucleic acids, proteins, metal ions, and small biological molecules. With the development of DNA nanotechnology, dynamic networks based on DNA hybridization can be used to amplify the signals of biosensors.
  • 1.6K
  • 07 Apr 2022
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