Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Iron Ore Reduction with Hydrogen
The steel industry represents about 7% of the world’s anthropogenic CO2 emissions due to the high use of fossil fuels. The CO2-lean direct reduction of iron ore with hydrogen is considered to offer a high potential to reduce CO2 emissions, and this direct reduction of Fe2O3 powder is investigated in this research.
  • 1.1K
  • 18 Sep 2021
Topic Review
Sustainable Supply Chain
Supply chain sustainability (SCS) in the age of Industry 4.0 and Big Data is a growing area of research. However, there are no systematic and extensive studies that classify the different types of research and examine the general trends in this area of research. This paper reviews the literature on sustainability, Big Data, Industry 4.0 and supply chain management published since 2009 and provides a thorough insight into the field by using bibliometric and network analysis techniques. A total of 87 articles published in the past 10 years were evaluated and the top contributing authors, countries, and key research topics were identified. Furthermore, the most influential works based on citations and PageRank were obtained and compared. Finally, six research categories were proposed in which scholars could be encouraged to expand Big Data and Industry 4.0 research on SCS. This paper contributes to the literature on SCS in the age of Industry 4.0 by discussing the challenges facing current research but also, more importantly, by identifying and proposing these six research categories and future research directions.
  • 1.1K
  • 06 Jun 2021
Topic Review
Valorization of Bread Waste into Value-Added Products
Bread is a universal food that is sold and consumed across the entire social and geographical spectrum. Bread waste is currently of increasing interest, as it is considered a huge global issue with serious environmental impacts and significant economic losses that have become even greater in the post-pandemic years due to an increase in cereal prices, which has led to higher production costs and bread prices. Meanwhile, many efforts have been initiated in the past decades to investigate methods of repurposing bread residues into fuel and chemicals such as bioethanol, biohydrogen, succinic acid, and various added-value products that can be exploited in versatile industries.
  • 1.1K
  • 09 Dec 2022
Topic Review
Centralised Generation
Centralised generation refers the common process of electricity generation through large-scale centralised facilities, through Transmission lines to consumer. These facilities are usually located far away from consumers and distribute the electricity through high voltage transmission lines to a substation where it is then distributed to consumers. The basic concept being that incredibly large stations create electricity for a large group of people. The Vast majority of electricity used in Australia as well as the United States is created from Centralised Generation. Most Centralised Power Generation comes from large power plants run by fossil fuels such as coal or natural gas. Nuclear or large hydroelectricity plants are also commonly used. Many disagree with the processes of Centralised Generation as it often relies on electrical generation through processes of the combustion of fossil fuels, which are bad for the environment. However unsustainable the current system is, it is by far the most widely used, reliable and efficient system that is currently in use. Centralised Generation is fundamentally the opposite of distributed generation. Distributed generation is the small-scale generation of electricity to smaller groups of consumers. This can also include independently producing electricity by either solar or wind power. In recent years Distributed generation as has seen a spark in popularity due to its propensity to use renewable energy generation methods such as wind and solar.
  • 1.1K
  • 23 Nov 2022
Topic Review
Grasshopper (Rocket)
Grasshopper and the Falcon 9 Reusable Development Vehicles (F9R Dev) were experimental flight test reusable rockets that performed vertical takeoffs and landings. The project was privately funded by SpaceX, with no funds provided by any government until later on. Two prototypes were built, and both were launched from the ground. Grasshopper was announced in 2011 and began low-altitude, low-velocity hover/landing testing in 2012. The initial Grasshopper test vehicle was 106 ft (32 m) tall and made eight successful test flights in 2012 and 2013 before being retired. A second Grasshopper-class prototype was the larger and more capable Falcon 9 Reusable Development Vehicle (F9R Dev, also known as F9R Dev1) based on the Falcon 9 v1.1 launch vehicle. It was tested at higher altitudes and was capable of much higher velocity but was never tested at high velocity. The F9R Dev1 vehicle was built in 2013–2014 and made its first low-altitude flight test on 17 April 2014; it was lost during a three-engine test at the McGregor test site on 22 August 2014, which ended the low-velocity test program. Further expansion of the flight test envelope for the reusable rocket was moved to descending Falcon 9 boosters that had been used on orbital flight trajectories on commercial orbital flights of the Falcon 9. The Grasshopper and F9R Dev tests were fundamental to the development of the reusable Falcon 9 and Falcon Heavy rockets, which require vertical landings of the near-empty Falcon 9 and Falcon Heavy first-stage booster tanks and engine assemblies. The Grasshopper and the F9R Dev tests led into a series of high-altitude, high-speed controlled-descent tests of post-mission (spent) Falcon 9 booster stages that accompanied the commercial Falcon 9 missions since September 2013. The latter eventually resulted in the first successful booster landing on 21 December 2015.
  • 1.1K
  • 16 Nov 2022
Topic Review
Sustainable Supplier Selection and Criteria
Sustainable supplier selection (SSS) is gaining popularity as a practical method to supply chain sustainability among academics and practitioners. In addition to balancing economic, social, and environmental factors, the emergence of the COVID-19 pandemic has affected the selection of long-term suppliers to ensure sustainable supply chains, recover better from the pandemic and effectively respond to any future unprecedented crises.
  • 1.1K
  • 23 May 2022
Topic Review
Spins in Semiconductor Nanoparticles
- Spin-dependent phenomena in semiconductors are analyzed starting from a theory of the dynamic nuclear polarization via numerous insightful findings in the realm of characterization and control through the nuclear spin polarization in nanoparticles and their aggregates into microparticles as potential contrast agents for magnetic resonance imaging (MRI) applications.  - Electron spin-dependent process of the photosensitized generation of singlet oxygen in porous silicon (Si) for photodynamic therapy application and design of Si-based nanoparticles with electron spin centers for MRI contrasting for cancer theranostics are discussed.  
  • 1.1K
  • 12 Jan 2021
Topic Review
GaN Electronic Devices
GaN has been widely used to develop devices for high-power and high-frequency applications owing to its higher breakdown voltage and high electron saturation velocity. The GaN HEMT radio frequency (RF) power amplifier is the first commercialized product that is fabricated using the conventional Au-based III–V device manufacturing process. In recent years, owing to the increased applications in power electronics, and expanded applications in RF and millimeter-wave (mmW) power amplifiers for 5G mobile communications, the development of high-volume production techniques derived from CMOS technology for GaN electronic devices has become highly demanded. 
  • 1.1K
  • 01 Jul 2021
Topic Review
Latency Compensated Visual-Inertial Odometry
In visual-inertial odometry (VIO), inertial measurement unit (IMU) dead reckoning acts as the dynamic model for flight vehicles while camera vision extracts information about the surrounding environment and determines features or points of interest. With these sensors, the most widely used algorithm for estimating vehicle and feature states for VIO is an extended Kalman filter (EKF). The design of the standard EKF does not inherently allow for time offsets between the timestamps of the IMU and vision data. In fact, sensor-related delays that arise in various realistic conditions are at least partially unknown parameters. A lack of compensation for unknown parameters often leads to a serious impact on the accuracy of VIO systems and systems like them. To compensate for the uncertainties of the unknown time delays, this study incorporates parameter estimation into feature initialization and state estimation. Moreover, computing cross-covariance and estimating delays in online temporal calibration correct residual, Jacobian, and covariance. Results from flight dataset testing validate the improved accuracy of VIO employing latency compensated filtering frameworks. The insights and methods proposed here are ultimately useful in any estimation problem (e.g., multi-sensor fusion scenarios) where compensation for partially unknown time delays can enhance performance.
  • 1.1K
  • 29 Apr 2021
Topic Review
Biowastes on Soil Remediation
Biowastes refer to the biodegradable food residues from private household and food industry, garden industry, municipal wastes, and sewage sludge.
  • 1.1K
  • 29 Jul 2021
  • Page
  • of
  • 678
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Video Production Service
Feedback