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Biography
John Olsen Lear
John Olsen Lear (December 3, 1942 – March 29, 2022) was an influential conspiracy theorist, record-breaking pilot, and a one-time candidate for State Senate.[1][2][3] Unlike previous UFO conspiracy theorists, Lear promoted a story of alien collusion with secret governmental forces.[1] Lear's tale left a lasting influence on the UFO movement -- one author observed "in the early years [UFO writ
  • 8.2K
  • 14 Dec 2022
Topic Review
Bayraktar Tactical UAS
The Bayraktar Tactical UAS is a surveillance and reconnaissance unmanned aerial vehicle (UAV) initially developed for the Turkish Armed Forces. It is developed by the Kale-Baykar, a joint venture between the Kale Group and Baykar Technologies. In 2014, Bayraktar held the national endurance and altitude record for Turkey's unmanned aerial vehicles (UAV). It set a record for autonomous flight endurance when it flew 24 hours and 34 minutes at 18,000 feet on 5 August 2014. It furthermore recorded highest altitude of 27,030 feet on its flight on 14 June 2014 with full payload. Bayraktar TB2 successfully demonstrated firing of ROKETSAN MAM-L Smart Micro Munition with 100% accuracy in December 2015. While the Turkish Armed Forces describes Bayraktar as "Tactical UAV Class" to prevent it from being a competitor to the TAI Anka UAV, international standards would classify it as a medium-altitude long-endurance UAV. With its 650 kg MTOW and 12 meters wingspan platform powered by an internal combustion engine, Bayraktar is capable of flying at 22,500 feet and loitering for more than 24 hours.
  • 8.2K
  • 24 Oct 2022
Topic Review
Addiction and Spending in Gacha Games
Gacha games are the most dominant games on the mobile market. These are free-to-play games with a lottery-like system, where the user pays with in-game currency to enter a draw in order to obtain the character or item they want. If a player does not obtain what he hoped for, there is the option of paying with his own money for more draws, and this is the main way to monetize the Gacha game.
  • 8.2K
  • 21 Jul 2023
Topic Review
Fly Ash
Fly ash or coal fly ash causes major global pollution in the form of solid waste and is classified as a “hazardous waste”, which is a by-product of thermal power plants produced during electricity production. Si, Al, Fe Ca, and Mg alone form more than 85% of the chemical compounds and glasses of most fly ashes. Fly ash has a chemical composition of 70–90%, as well as glasses of ferrous, alumina, silica, and CaO. Therefore, fly ash could act as a reliable and alternative source for ferrous, alumina, and silica. The ferrous fractions can be recovered by a simple magnetic separation method, while alumina and silica can be extracted by chemical or biological approaches. Alumina extraction is possible using both alkali- and acid-based methods, while silica is extracted by strong alkali, such as NaOH. Chemical extraction has a higher yield than the biological approaches, but the bio-based approaches are more environmentally friendly. Fly ash can also be used for the synthesis of zeolites by NaOH treatment of variable types, as fly ash is rich in alumino-silicates. The present review work deals with the recent advances in the field of the recovery and synthesis of ferrous, alumina, and silica micro and nanoparticles from fly ash.
  • 8.2K
  • 06 Apr 2021
Topic Review
Estimation of Maize Yield Per Harvest Area
Maize (Zea mays L.) is one of the most important annual cereal crops in the world, providing a staple food, and being used as source of income for many populations in developing countries. Different methods can be used for estimating maize yields depending on the purpose for which the crop was produced. The estimation of yield can be calculated using kernel weight at harvest, plot area harvested, plant density, and moisture content of grain at harvest. 
  • 8.2K
  • 10 Jan 2022
Topic Review
Head-Up Display (Video Gaming)
In video gaming, the HUD (heads-up display) or status bar is the method by which information is visually relayed to the player as part of a game's user interface. It takes its name from the head-up displays used in modern aircraft. The HUD is frequently used to simultaneously display several pieces of information including the main character's health, items, and an indication of game progression (such as score or level).
  • 8.2K
  • 31 Oct 2022
Topic Review
Seaport
Seaports are well known as the medium that has evolved into the central link between sea and land for complex marine activities. The growth in maritime logistics particularly necessitates a large volume of energy supply in order to maintain the operation of sea trade, resulting in an imbalance between generation and demand sides. Future projections for three major concerns show an increase in load demand, cost of operation, and environmental issues. The involvement of a variety of heavy loads such as all-electric ships, cranes, cold ironing, and buildings infrastructure renders it a complicated arrangement task in several aspects, which necessitates further research and leaves space for improvement.
  • 8.2K
  • 06 Dec 2021
Topic Review
Fundamental Properties of Hempcrete
A bio-fiber composite made up of hemp hurd or shiv and mineral binder, hempcrete is a form of lime-based construction material. The binder that is made by combining water with these ingredients is expected to completely coat all of the hemp shiv particles after sufficient mixing. A chemical reaction between the lime binder and water hardens the binder, cementing the hurd pieces together. The term “bonded cellulose insulation” could be broadly used to describe this mixture. Hempcrete is what is left after the binder has dried and been allowed to build up strength with time. 
  • 8.2K
  • 21 Feb 2024
Topic Review
Laser Absorption Spectroscopy
Laser absorption spectroscopy (LAS) is an absorption spectroscopic method that employs a laser as the light source and measures the chemical concentration based on detection of a variation of laser beam intensity after transmission along the optical path. 
  • 8.2K
  • 10 Sep 2020
Topic Review
Peroxisomal β-Oxidation
It is not paradoxical that what has been overlooked tends to be of great importance. Peroxisomes, the widely distributed organelles in the body, play irreplaceable roles in cellular metabolism, especially in fatty acid oxidation (FAO) and the generation and elimination of reactive oxygen species (ROS).
  • 8.2K
  • 15 Jul 2022
Topic Review
Principles of SERS
SERS (Surface-enhanced Raman spectroscopy) is based on the amplification of the Raman response of an analyte interacting with the surface plasmon of metals such as Au, Ag, or Cu; in some cases, the response results enough to achieve the single–molecule detection
  • 8.2K
  • 21 Apr 2021
Topic Review
eCommerce and Small and Medium Enterprises
The rise of smaller businesses has been an essential trend since the 1990s, when they became engines for economic development. Now, Small and Medium Enterprises (SMEs) across the world are increasingly relying on eCommerce channels to create and capture value. The growth in eCommerce operations is being fueled by several global and technological developments. eCommerce allows SMEs to benefit from globalization by expanding their ability to access customers around the world and across customer demographics and categories. This emergence of a new range of markets has made strategic flexibility essential for SMEs, as such expansion requires a consistent rethinking and adapting to continually changing dynamics in a global environment.
  • 8.2K
  • 07 May 2022
Topic Review
Problems Associated with Plant Micropropagation
The production of micropropagated plants in plant-tissue-culture laboratories and nurseries is the most important method for propagation of many economic plants. Micropropagation based on tissue-culture technology involves large-scale propagation, as it allows multiplication of a huge number of true-to-type propagules in a very short time and in a very limited space, as well as all year round, regardless of the climate.
  • 8.2K
  • 04 Aug 2022
Topic Review
Free Society
The term free society is used frequently by American libertarian theorists to denote a society in which their ideal political, legal and economic aims are in effect. In a theoretical free society, all individuals act voluntarily, having the freedom to obtain the power and resources to fulfill their own potential. Adlai Stevenson defined free societies as a society in which individuals find it "safe to be unpopular". Others, such as Chandran Kukathas, described a free society as dependent upon the "principle of freedom of association". Cindy Cohn has argued that the freedom to have a "private conversation" is "central to a free society". These interpretations can also be elaborated in terms of freedom of speech – if people have a right to express their views without fear of arrest, imprisonment, or physical harm. In a free society, individuals would organize in voluntary associations, including free market and communal societies. Individuals would gain more prosperity due to the lack of restrictions on trade and wealth creation.
  • 8.2K
  • 11 Oct 2022
Topic Review
Laïcité
Laïcité ([la.i.si.te]), literally "secularity", is a French concept of secularism. It discourages religious involvement in government affairs, especially religious influence in the determination of state policies; it also forbids government involvement in religious affairs, and especially prohibits government influence in the determination of religion. Laïcité does not preclude a right to the free exercise of religion. Dictionaries ordinarily translate laïcité as "secularity" or "secularism" (the latter being the political system), although it is sometimes rendered in English as laicity or laicism by its opponents. While the term was first used with this meaning in 1871 in the dispute over the removal of religious teachers and instruction from elementary schools, the word laïcisme dates to 1842. In its strict and official acceptance, it is the principle of separation of church (or religion) and state. Etymologically, laïcité is a noun formed by adding the suffix -ité (English -ity, Latin -itās) to the Latin adjective lāicus, a loanword from the Greek λᾱϊκός (lāïkós "of the people", "layman"), the adjective from λᾱός (lāós "people"). French secularism has a long history. For the last century, the French government policy has been based on the 1905 French law on the Separation of the Churches and the State.
  • 8.2K
  • 04 Nov 2022
Topic Review
Mercedes-Benz W108
The Mercedes-Benz W108 and W109 are luxury cars produced by Mercedes-Benz from 1965 through to 1972 and 1973 in North America only. The line was an update of the predecessor W111 and W112 fintail sedans. The cars were successful in West Germany and in export markets including North America and Southeast Asia. During the seven-year run, a total of 383,361 units were manufactured.
  • 8.2K
  • 19 Oct 2022
Topic Review
Polyelectrolyte
Polyelectrolytes are polymers of oppositely charged ions and their properties differ profoundly than their repeating units. Over recent years, much advancement has been made in the synthesis, characterization, and application of polyelectrolytes and polyelectrolyte complexes (PECs). It has many applications as flocculation agents, dispersant agents, and as super-plasticizers. In this article, the synthesis, types, characteristics, and application of PECs mainly for drug delivery and dynamics study are reviewed.
  • 8.2K
  • 27 Oct 2020
Topic Review
Pollen Germination in Gymnosperms
Gymnosperms are amazing representatives of the flora. On the one hand, they are ancient plants with primitive characteristics of anatomical structure; on the other hand, they are perfectly adapted to their habitat and are the dominant species in many ecosystems due to their impressive size and longevity, with their reproductive system being of particular interest. It has progressive features, because in this group the reduced male gametophyte—pollen grain—first appeared, as well as the ability to form seeds. In addition, this group still represents a wide variety of reproductive patterns, strategies, and relationships. For example, the degree of gametophyte reduction varies, there are both zooidogamy and siphonogamy, and the reproductive process can both be relatively fast and last over several years.
  • 8.2K
  • 20 Jul 2021
Topic Review
Urban Open Space
In land-use planning, urban open space is open-space areas reserved for parks, "green spaces", and other open areas. The landscape of urban open spaces can range from playing fields to highly maintained environments to relatively natural landscapes. Generally considered open to the public, urban open spaces are sometimes privately owned, such as higher education campuses, neighborhood/community parks/gardens, and institutional or corporate grounds. Areas outside city boundaries, such as state and national parks as well as open space in the countryside, are not considered urban open space. Streets, piazzas, plazas and urban squares are not always defined as urban open space in land use planning.
  • 8.2K
  • 14 Oct 2022
Topic Review
Bloch Wave
A Bloch wave (also called Bloch state or Bloch function or Bloch wavefunction), named after Swiss physicist Felix Bloch, is a kind of wave function which can be written as a plane wave modulated by a periodic function. By definition, if a wave is a Bloch wave, its wavefunction can be written in the form: where [math]\displaystyle{ \mathbf{r} }[/math] is position, [math]\displaystyle{ \psi }[/math] is the Bloch wave, [math]\displaystyle{ u }[/math] is a periodic function with the same periodicity as the crystal, the wave vector [math]\displaystyle{ \mathbf{k} }[/math] is the crystal momentum vector, [math]\displaystyle{ \mathrm{e} }[/math] is Euler's number, and [math]\displaystyle{ \mathrm{i} }[/math] is the imaginary unit. Bloch waves are important in solid-state physics, where they are often used to describe an electron in a crystal. This application is motivated by Bloch's theorem, which states that the energy eigenstates for an electron in a crystal can be written as Bloch waves (more precisely, it states that the electron wave functions in a crystal have a basis consisting entirely of Bloch wave energy eigenstates). This fact underlies the concept of electronic band structures. These Bloch wave energy eigenstates are written with subscripts as [math]\displaystyle{ \psi_{n\mathbf{k}} }[/math], where [math]\displaystyle{ n }[/math] is a discrete index, called the band index, which is present because there are many different Bloch waves with the same [math]\displaystyle{ \mathbf{k} }[/math] (each has a different periodic component [math]\displaystyle{ u }[/math]). Within a band (i.e., for fixed [math]\displaystyle{ n }[/math]), [math]\displaystyle{ \psi_{n\mathbf{k}} }[/math] varies continuously with [math]\displaystyle{ \mathbf{k} }[/math], as does its energy. Also, for any reciprocal lattice vector [math]\displaystyle{ \mathbf{K} }[/math], [math]\displaystyle{ \psi_{n\mathbf{k}}=\psi_{n(\mathbf{k+K})} }[/math]. Therefore, all distinct Bloch waves occur for values of [math]\displaystyle{ \mathbf{k} }[/math] which fall within the first Brillouin zone of the reciprocal lattice.
  • 8.2K
  • 30 Nov 2022
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