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Topic Review
Energy Situation in Central Asia
Despite plentiful domestically available energy resources, the energy supply in Central Asia is very unevenly distributed between urban and rural areas. Almost half of the total population of Central Asia lives in rural areas and there is a lack of access to modern energy services to meet primary needs. 
  • 2.2K
  • 29 Jul 2021
Biography
Anousheh Ansari
Anousheh Ansari (Persian: Anuŝe Ansāri‎; née Raissyan;[1] born September 12, 1966) is an Iranian-American engineer and co-founder and chairwoman of Prodea Systems. Her previous business accomplishments include serving as co-founder and CEO of Telecom Technologies, Inc. (TTI). The Ansari family is also the title sponsor of the Ansari X Prize. On September 18, 2006, a few days after her 40th
  • 2.2K
  • 17 Nov 2022
Topic Review
Wind Turbines
Wind turbines (WTs) are large devices utilized to convert the wind's kinetic energy into electricity. There are several different typologies of WTs, the most common type being the so-called Horizontal Axis Wind Turbine (HAWT) systems. In this configuration, the rotation axis of the rotor is parallel to the ground. Specific attention must be paid to the orientation with respect to the wind direction, which is different from other types of wind turbines such as those with a vertical axis (VAWT), whose orientation is independent of the prevailing wind direction. For HAWT, the three-bladed upwind configuration is the most common one, with the rotor facing the incoming wind. WTs can be deployed both on- or offshore and have very different blade lengths, which result in different sizes (especially regarding the tower height) and power output. Due to fatigue and exposure to outdoor elements, WT monitoring and diagnostics are strictly needed to reduce structural and mechanical failure and achieve cost-effective energy production. This requires both the Structural Health Monitoring of the WTs load-bearing components (tower, blades, foundations, etc) and the Condition Monitoring of their mechanical parts (gearbox, generator, etc).
  • 2.2K
  • 02 Mar 2022
Topic Review
Information and Communication Technology
Information and Communication Technology (ICT) is seen as a way to enhance knowledge collection in the construction sector. Although the theoretical benefits of ICT implementation have been clarified, realizing such benefits is insufficient. This paper attempted a systematic analysis of the literature using ATLAS.ti 9 software to save, identify, and analyze this study’s data. A total of 102 articles were actively reviewed, including 82 Scopus journals and 20 conference papers published from 2003 to 2020. In this article, from a construction industry point of view, the ICT adoption process is considered as an interaction between technology, task, and an individual from a construction industry perspective. While ICT is acknowledged as a source of aggressive gain by both practitioners and scholars, ICT’s sole presence would definitely not guarantee achievement in the industry’s ICT approval. Companies cannot grasp the full benefits of ICT, except that users are able to adopt the technology. Hence, the issues related to ICT adoption need to be examined.
  • 2.2K
  • 13 Nov 2020
Topic Review
Enzymatic Transesterification in Biodiesel Production
       Biodiesel constitutes an attractive source of energy because it is renewable,  biodegradable, and non-polluting. Up to 20% biodiesel can be blended with fossil diesel and is being produced and used in many countries. Biodiesel is produced through the transesterification reaction of fat waste with a short-chain alcohol, usually methanol, in the presence of a catalyst. Animal fats, usually found as waste from slaughterhouses, meat processing industry, and cooking facilities, constitute an important waste with costly treatment that can be reduced if used as feedstock for biodiesel production. Animal fat waste represents near 6% of total feedstock used to produce biodiesel through alkaline catalysis transesterification after its pretreatment. Lipase transesterification has some advantages such as the requirement of mild conditions, absence of pretreatment, no soap formation, simple downstream purification process and generation of high quality biodiesel. However, it has some disadvantages like the cost of the enzyme, its poor stability, and the enzyme deactivation by alcohol, that can be partly overcome through enzyme immobilization. A few companies are using liquid lipase formulations and, in some cases, immobilized lipases for industrial biodiesel production.        Biodiesel constitutes an attractive source of energy because it is renewable,  biodegradable, and non-polluting. Up to 20% biodiesel can be blended with fossil diesel and is being produced and used in many countries. Biodiesel is produced through the transesterification reaction of fat waste with a short-chain alcohol, usually methanol, in the presence of a catalyst. Animal fats, usually found as waste from slaughterhouses, meat processing industry, and cooking facilities, constitute an important waste with costly treatment that can be reduced if used as feedstock for biodiesel production. Animal fat waste represents near 6% of total feedstock used to produce biodiesel through alkaline catalysis transesterification after its pretreatment. Lipase transesterification has some advantages such as the requirement of mild conditions, absence of pretreatment, no soap formation, simple downstream purification process and generation of high quality biodiesel. However, it has some disadvantages like the cost of the enzyme, its poor stability, and the enzyme deactivation by alcohol, that can be partly overcome through enzyme immobilization. A few companies are using liquid lipase formulations and, in some cases, immobilized lipases for industrial biodiesel production.
  • 2.2K
  • 30 Oct 2020
Topic Review
International Roughness Index
The International Roughness Index (IRI) is the roughness index most commonly obtained from measured longitudinal road profiles. It is calculated using a quarter-car vehicle math model, whose response is accumulated to yield a roughness index with units of slope (in/mi, m/km, etc.). This performance measure has less stochasticity and subjectivity in comparison to other pavement performance indicators, but it is not completely devoid of randomness. The sources of variability in IRI data include the difference among the readings of different runs of the test vehicle and the difference between the readings of the right and left wheel paths. Despite these facts, since its introduction in 1986, the IRI has become the road roughness index most commonly used worldwide for evaluating and managing road systems. The measurement of IRI is required for data provided to the United States Federal Highway Administration, and is covered in several standards from ASTM International: ASTM E1926 - 08, ASTM E1364 - 95(2005), and others. IRI is also used to evaluate new pavement construction, to determine penalties or bonus payments based on smoothness.
  • 2.2K
  • 31 Oct 2022
Topic Review
Compaq Presario 2200
The Compaq Presario 2200 is a small form factor desktop PC produced by Compaq from 1997 to 1998. It was produced as a slim, small form factor machine mainly intended for budget-minded consumers. When launched, it had 16 MB of EDO DRAM that was expandable up to 80 MB and a Cyrix MediaGXi microprocessor, clocking at 180 MHz. It did not include an Ethernet port; however, the modem can be swapped out for a compatible 8-bit ISA Ethernet card to allow the computer to be connected to the Internet or a LAN network. There are no USB ports on the computer, even though the small metal flap might suggest that Compaq considered installing USB ports during the time the computer was developed. This computer model is not to be confused with the newer Compaq Presario 2200 laptop computer.
  • 2.2K
  • 09 Nov 2022
Topic Review
SpaceX Rocket Engines
Since the founding of SpaceX in 2002, the company has developed four families of rocket engines — Merlin, Kestrel, Draco and SuperDraco — and is currently developing another rocket engine: Raptor.
  • 2.2K
  • 17 Oct 2022
Topic Review
Switched-Capacitor-Based Converters
An extensive entry of basic concepts and switched capacitor structures employed in the conception of DC-DC converters is presented.
  • 2.2K
  • 06 May 2021
Topic Review
IoT and the Energy Sector
Integration of renewable energy and optimization of energy use are key enablers of sustainable energy transitions and mitigating climate change. Modern technologies such the Internet of Things (IoT) offer a wide number of applications in the energy sector, i.e, in energy supply, transmission and distribution, and demand. IoT can be employed for improving energy efficiency, increasing the share of renewable energy, and reducing environmental impacts of the energy use.
  • 2.2K
  • 26 Sep 2021
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