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Topic Review
Graph Modeling of Shop Schedulings
Graphs are powerful tools to model manufacturing systems and scheduling problems. The complexity of these systems and their scheduling problems has been substantially increased by the ongoing technological development. Thus, it is essential to generate sustainable graph-based modeling approaches to deal with these excessive complexities. Graphs employ nodes and edges to represent the relationships between jobs, machines, operations, etc. Despite the significant volume of publications applying graphs to shop scheduling problems, the literature lacks a comprehensive survey study. We proposed the first comprehensive review paper which 1) systematically studies the overview and the perspective of this field, 2) highlights the gaps and potential hotspots of the literature, and 3) suggests future research directions towards sustainable graphs modeling the new intelligent/complex systems. We carefully examined 143 peer-reviewed journal papers published from 2015 to 2020. About 70% of our dataset were published in top-ranked journals which confirms the validity of our data and can imply the importance of this field. After discussing our generic data collection methodology, we proposed categorizations over the properties of the scheduling problems and their solutions. Then, we discussed our novel categorization over the variety of graphs modeling scheduling problems. Finally, as the most important contribution, we generated a creative graph-based model from scratch to represent the gaps and hotspots of the literature accompanied with statistical analysis on our dataset. Our analysis showed a significant attention towards job shop systems (56%) and Un/Directed Graphs (52%) where edges can be either directed, or undirected, or both. Whereas 14% of our dataset applied only Undirected Graphs, and 11% targeted hybrid systems, e.g., mixed shop, flexible and cellular manufacturing systems which shows potential future research directions.
  • 3.4K
  • 25 May 2021
Topic Review
Agriculture in Marginal Lands
The term ‘marginal’ was originally used under the umbrella of economic theorizing to describe an area under given conditions where cost-effective production is not remunerated. Since then, different definitions describing the concept of marginality and marginal environments have emerged, highlighting the complex nature of marginality and how various unfavorable conditions disadvantage individuals and communities living in these areas. In the context of the agricultural economy, the term “margins of cultivation” is used to describe economically marginal agricultural lands where revenue from optimal production just equals (or is lower than, in some instances) the costs of production, leading to zero (negative) profit or economic loss. To capture this specific economic context, FAO and UNEP have classified land supporting a yield of only up to 40 percent of its productivity potential as marginal. Marginal lands are also identified as areas where “cost-effective production is not possible under given conditions, cultivation techniques, agriculture policies, and macro-economic and legal settings”. In this context, economically marginal land can be thought of as land that would not be cultivated at current output and input prices without the availability of government support programs. Marginal lands are mostly abandoned, as they are disadvantaged due to factors such as changing commodity markets, international competition, or the demographics of land owners and farm operators.
  • 3.4K
  • 07 Sep 2021
Topic Review
Ken Cuccinelli
Kenneth Thomas Cuccinelli II (/ˈkuːtʃɪˈnɛli/ KOO-chi-NEL-ee; born July 30, 1968) is an American politician and lawyer currently serving as Principal Deputy Director of the U.S. Citizenship and Immigration Services (USCIS) agency and Acting Deputy Secretary of Homeland Security. He previously served as the 46th attorney general of Virginia from 2010 until 2014, and acting Director of USCIS agency. Before this, he was in the Virginia Senate, representing the 37th district in Fairfax County from 2002 until he took office as attorney general in 2010. On May 18, 2013, Cuccinelli won the Republican Party's gubernatorial nomination at the state party convention. Cuccinelli was the Republican nominee for Governor of Virginia in the 2013 Virginia gubernatorial election, losing to the Democratic nominee, Terry McAuliffe, by 56,435 votes or 2.5% of the total votes cast. A self-described opponent of homosexuality, Cuccinelli in his position as Virginia Attorney General defended anti-sodomy laws and prohibitions on same-sex marriage. Cuccinelli rejects the scientific consensus on climate change, and in his position as Attorney General investigated climate scientists whom he accused of fraud. He filed lawsuits against the Obama administration’s Environmental Protection Agency. Characterized as an immigration hard-liner, Cuccinelli sought to prohibit undocumented immigrants from attending universities, repeal birthright citizenship, and force employees to speak English in the workplace. As CIS Director, he implemented and defended policies that would reject applications for visas or permanent residency for immigrants considered likely to utilize publicly funded benefits programs.
  • 3.4K
  • 12 Oct 2022
Topic Review
Grandiosity
In the field of psychology, the term grandiosity refers to an unrealistic sense of superiority, characterized by a sustained view of one's self as better than others, which is expressed by disdainfully criticising them, overinflating one's own capability and belittling them as inferior; and refers to a sense of personal uniqueness, the belief that few other people have anything in common with oneself, and that one can only be understood by a few, very special people. The personality trait of grandiosity is principally associated with narcissistic personality disorder (NPD), but also is a feature in the occurrence and expression of antisocial personality disorder, and the manic and hypomanic episodes of bipolar disorder.
  • 3.4K
  • 25 Nov 2022
Topic Review
Wireless Sensor Network Technology
Wireless sensor network technology enables distributed sensing through efficient data communication between a multitude of environmental sensors. WSN is still a relatively new area of research, but the communication technology used for low-cost, low-power wireless networks has advanced greatly in recent decades.
  • 3.4K
  • 10 Jan 2023
Topic Review
Deep-Learning-Based Channel Estimation Methods
With the rapid development of wireless communication technology, intelligent communication has become one of the mainstream research directions after the fifth generation (5G). In particular, deep learning has emerged as a significant artificial intelligence technology widely applied in the physical layer of wireless communication for achieving intelligent receiving processing. Channel estimation, a crucial component of physical layer communication, is essential for further information recovery. 
  • 3.4K
  • 25 Dec 2023
Topic Review
Terpenes and Terpenoids for Bioplastics
This entry describes the most common types of bioplastics and biopolymers, and focuses specifically on the polymerization of terpenes and terpenoids, which represent a source of promising monomers to create bio-based polymers and copolymers.
  • 3.4K
  • 25 Aug 2021
Topic Review
Energy Crops
Energy crops are dedicated cultures directed for biofuels, electricity, and heat production. Due to their tolerance to contaminated lands, they can alleviate and remediate land pollution by the disposal of toxic elements and polymetallic agents. Moreover, these crops are suitable to be exploited in marginal soils (e.g., saline), and, therefore, the risk of land-use conflicts due to competition for food, feed, and fuel is reduced, contributing positively to economic growth, and bringing additional revenue to landowners.
  • 3.4K
  • 29 Jun 2022
Topic Review
Nonaqueous Titration
Nonaqueous titration is the titration of substances dissolved in solvents other than water. It is the most common titrimetric procedure used in pharmacopoeial assays and serves a double purpose: it is suitable for the titration of very weak acids and very weak bases, and it provides a solvent in which organic compounds are soluble. The most commonly used procedure is the titration of organic bases with perchloric acid in anhydrous acetic acid. These assays sometimes take some perfecting in terms of being able to judge the endpoint precisely. The Karl Fischer titration for water content is another nonaqueous titration, usually done in methanol or sometimes in ethanol. Since water is the analyte in this method, it cannot also be used as the solvent.
  • 3.4K
  • 14 Oct 2022
Topic Review
Hydrogen Storage in Activated Carbons
With the rising demand for H2 in the past decades and its favorable characteristics as an energy carrier, the escalating USA consumption of pure H2 can be projected to reach 63 million tons by 2050. Despite the tremendous potential of H2 generation and its widespread application, transportation and storage of H2 have remained the major challenges of a sustainable H2 economy. Recently, the literature has been stressing the need to develop biomass-based activated carbons as an effective H2 storage material, as these are inexpensive adsorbents with tunable chemical, mechanical, and morphological properties.  This article reviews the current research trends and perspectives on the role of various properties of biomass-based activated carbons on its H2 uptake capacity. The critical aspects of the governing factors of H2 storage, namely, the surface morphology (specific surface area, pore volume, and pore size distribution), surface functionality (heteroatom and functional groups), physical condition of H2 storage (temperature and pressure), and thermodynamic properties (heat of adsorption and desorption), are discussed. A comprehensive survey of the literature showed that an “ideal” biomass-based activated carbon sorbent with a micropore size typically below 10 Å, micropore volume greater than 1.5 cm3/g, and high surface area of 4000 m2/g or more may help in substantial gravimetric H2 uptake of >10 wt% at cryogenic conditions (−196 °C), as smaller pores benefit by stronger physisorption due to the high heat of adsorption.
  • 3.4K
  • 01 Apr 2021
Topic Review
Tonsillolith
Tonsilloliths, also known as tonsil stones, are soft aggregates of bacterial and cellular debris that form in the tonsillar crypts, the crevices of the tonsils. While they occur most commonly in the palatine tonsils, they may also occur in the lingual tonsils. Tonsil stones are common. Tonsilloliths have been recorded weighing from 0.3 g to 42 g. Protruding tonsilloliths may feel like foreign objects lodged in the tonsil crypt. They may be a nuisance and difficult to remove, but are usually not harmful. They are one of the causes of bad breath and always give off a putrid smell.
  • 3.4K
  • 11 Nov 2022
Topic Review
Physaliidae
The Portuguese man o' war (Physalia physalis), also known as the man-of-war, bluebottle, blue bottle jellyfish, or floating terror is a marine hydrozoan found in the Atlantic Ocean and the Indian Ocean. It is considered to be the same species as the Pacific man o' war, which is found mainly in the Pacific Ocean. The Portuguese man o' war is the only species in the genus Physalia, which in turn is the only genus in the family Physaliidae. It has numerous venomous microscopic nematocysts which deliver a painful sting powerful enough to kill fish, and has been known to occasionally kill humans. Although it superficially resembles a jellyfish, the Portuguese man o' war is in fact a siphonophore. Like all siphonophores, it is a colonial organism, made up of many smaller units called zooids. All zooids in a colony are genetically identical, but fulfill specialized functions such as feeding and reproduction, and together allow the colony to operate as a single individual.
  • 3.4K
  • 27 Oct 2022
Topic Review
Industrial Production of Antibiotics in Fungi
The natural fermentation of antibiotics, along with semi-synthetic and synthetic approaches, is one of the most important methods for their production. The majority of the antibiotic market comes from the fermentation of high-yielding (HY) fungal strains. These strains have been obtained since the 1950s from wild-type (WT) isolates as a result of classical strain improvement (CSI) programs primarily involving multi-round random mutagenesis and screening.
  • 3.4K
  • 19 Dec 2023
Topic Review
Transducer Technologies for Biosensors and Their Wearable Applications
Biosensors refer to the collaboration of receptors that recognize target analytes and transducers that translate this recognition into a detectable signal. Biological molecules such as enzymes, nucleic acids, antibodies, or their synthetic analogues can serve as bio-receptors to bind the analyte of interest. To form a biosensor device that detects or measures the biological events or changes, the targeted matching of the bio-receptor and the analyte should be evaluated quantitatively, making the transducers indispensable components of a biosensor. Availability of various bio-receptors, transducers, and possible combinations of both components constitute various ways to classify biosensors. Compared to conventional sensors based on rigid semiconductors, metals, and ceramics, elastomers are advantageous since they exhibit the highest level of strain behavior for wearable applications. 
  • 3.4K
  • 09 Jun 2022
Topic Review Peer Reviewed
The Mysteries of the White Truffle: Its Biology, Ecology and Cultivation
Tuber magnatum Picco is the most expensive of the truffles and a great deal of research has been carried out in an attempt to solve the mysteries of its ecology and biology. However, considerable work remains to be done particularly on those secrets of its life cycle that remain a mystery. It is known that T. magnatum is heterothallic, but it has yet to be determined how fertilization occurs between the two strains of different mating types. It is also known that the white truffle is an ectomycorrhizal fungus, and its mycorrhizas can be produced in greenhouses, but then they seem to disappear in the field. The role of other soil microorganisms, fungi and bacteria, on its soil mycelial development and fructification is intriguing but is far from being completely understood. All these uncertainties have made the cultivation of T. magnatum extremely difficult and only recently have we had the scientific proofs that it is possible. Even so, many questions remain unanswered and the management practices of T. magnatum plantations are still to be better defined to also enable the taming of this truffle.
  • 3.4K
  • 11 Jan 2023
Topic Review
Nuclear Pore Complex
The import and export of proteins requires interaction with the components of the nuclear envelope (NE), which is formed by a double membrane that harbor protein channels called nuclear pore complexes (NPCs). NPCs are formed by multiple copies of Nups that participate in the bi-directional nucleus–cytoplasmic transport of macromolecules, ribosomal subunits, viral proteins and RNAs (mRNAs, rRNAs, tRNAs, miRNAs) from both cellular and viral origin.
  • 3.4K
  • 28 Apr 2021
Topic Review
Finger Millet Production in Ethiopia
Finger millet (Eleusine coracana (L.) Gaertn) is a highly nutritious crop, predominantly grown in the semi-arid tropics of the world. The crop has medicinal value to human beings due to its human health benefits and being rich in calcium, iron and dietary fiber and gluten-free. Ethiopia is the center of the genetic diversity of the crop. However, the productivity of finger millet in the country is low (<2.4 tons ha−1) compared with its potential yield (6 tons ha−1). The yield gap in Ethiopia is due to a range of biotic and abiotic stresses and socio-economic constraints that are yet to be systemically documented and prioritized to guide future production and improved variety development and release. The objective of this study was to document finger millet production opportunities, constraints and farmer-preferred traits in Ethiopia as a guide to variety design in improvement programs. 
  • 3.4K
  • 13 Dec 2021
Topic Review
Woodcock–Johnson Tests of Cognitive Abilities
The Woodcock–Johnson Tests of Cognitive Abilities is a set of intelligence tests first developed in 1977 by Richard Woodcock and Mary E. Bonner Johnson (although Johnson's contribution is disputed). It was revised in 1989, again in 2001, and most recently in 2014; this last version is commonly referred to as the WJ IV. They may be administered to children from age two right up to the oldest adults (with norms utilizing individuals in their 90s). The previous edition WJ III was praised for covering "a wide variety of cognitive skills".
  • 3.4K
  • 20 Oct 2022
Topic Review
IBM Systems Network Architecture
Systems Network Architecture (SNA) is IBM's proprietary networking architecture, created in 1974. It is a complete protocol stack for interconnecting computers and their resources. SNA describes formats and protocols and is, in itself, not a piece of software. The implementation of SNA takes the form of various communications packages, most notably Virtual Telecommunications Access Method (VTAM), the mainframe software package for SNA communications.
  • 3.4K
  • 28 Oct 2022
Topic Review
Collagen Fibrils
Collagen fibrils are dissected from collagen rich tissues, such as rat tail tendons. Tissue samples such as tendons are sectioned with scalpels and washed with deionized water or phosphate-buffered saline. Subsequently, bundles of collagen fibers are collected with tweezers and then deposited on clean substrates such as microscope glass slides.
  • 3.4K
  • 06 Apr 2022
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