Universal Protoplanetary Disk Size under Complete Nonideal Magnetohydrodynamics: The Interplay between Ion-neutral Friction, Hall Effect, and Ohmic Dissipation

The role of nonideal magnetohydrodynamics has been proven critical during the formation of protoplanetary disks, particularly in regulating their sizes. We provide a simple model to predict the disk size under the interplay among ambipolar diffusion, the Hall effect, and ohmic dissipation. The model predicts a small disk size of around 20 au that depends only sublinearly on disk parameters, for a wide range of initial conditions of subsolar mass and moderate magnetization. It is able to explain phenomena manifested in existing numerical simulations, including the bimodal disk behavior under parallel and antiparallel alignment between the rotation and magnetic field. In the parallel configuration, the disk size decreases and eventually disappears. In the antiparallel configuration, the disk has an outer partition (or pseudodisk), which is flat, shrinking, and short-lived, as well as an inner partition, which grows slowly with mass and is long-lived. Even with significant initial magnetization, the vertical field in the disk can only dominate at the early stage when the mass is low, and the toroidal field eventually dominates in all disks.

‘Nothing is what it seems’: Posthumanism and late capitalism in Altered Carbon

This article explores how class politics are interpreted within Altered Carbon, the 2018 television series based on the 2002 book of the same name by Richard K. Morgan. The series follows Takeshi Kovacs, a soldier turned rebel turned private detective, as he awakens after 250 years in stasis. Like all humans in this fictional world, Kovacs’s existence, or essence, has been compressed into a small disk known as a cortical stack. Altered Carbon does not present a liberated or democratic future, instead, it demarcates how our posthuman fantasies can mimic, or fully embody, the class politics we see today in our late-capitalist society. Altered Carbon asks us to consider where the boundaries of the self and the body truly lie and how those boundaries, or lack thereof, are open for exploitation by those with financial means. We must critique how posthumanism has, or has not, taken up class. I believe this issue is most salient when we consider how class mediates our past, present and potential futures. I analyse the cortical stack itself as a posthumanist interpretation of Cartesian dualism and how that mind and body divide is central to maintaining capitalism through the alienation of the worker. Altered Carbon asks us to consider what happens when one’s flesh and one’s identity in and of itself become transferable and never truly one’s own.

DETERMINATION OF THE EFFICIENCY OF THE PROTECTION SYSTEM FOR CORE SEEDS FROM WEEDS AT VARIOUS METHODS OF TREATING SOIL UNDER CONDITIONS OF FOREST RIVER STEPPE

The article confirms the feasibility and effectiveness of modern herbicides in corn crops for various methods of tillage. According to the research results, a mixed type of weediness is formed in corn crops, among which the largest share is occupied by late spring late spring species, which accounted for 71,8 % of the total number of weeds that appeared during the growing season of the crop. These included: millet of chickens (Echinochloa crus-galli (L.) Roem.) – 16,1 %, blue bristles (Setaria glauca L.) – 30,4 %, among dicotyledons: small-flowered Galinsoga (Galinsoga rarviflora Cav. ) – 18,4 %, common thyroid (Amaranthus retroflexus L.) – 5,4 %. Early spring was 7,6 %, including white quinoa (Chenopodium album L.) – 7,5 %. Among wintering species, the shepherd's purse ordinary (Capsela bursa pastoris L. Medic) prevailed. – 3,9 %, odorless chamomile (Matricaria perforata Merat.) – 3,2 %, Field yarut (Thlaspi arvense L.) – 2,5 %, field violet (Viola arvensis Murr.) – 2,0 %, with ephemera - medium asterisk (Stellaria media L.) – 5,3 %. Perennial rootstock and weeds of sow thistle pink (Cirsium arvense (L.) Scop.) 0,9%, yellow sow thistle (Sonchus arvensis L.) – 0,1 %, field bindweed (Convolvulus arvensis L.) – 0,9 %, of perennial rhizome - creeping wheatgrass (Elytrigia repens L.) – 0.8%. An insignificant proportion of the species composition of weeds was occupied by perennial strzynekoreni and weeds. Also, when conducting research, it was found that the density of corn standing in the phase of full germination on arable land was in the range of 78,3–78,6 pcs./m2. For small disk processing, this indicator decreased to 78,1–78,2 pcs./m2. For the period of maize harvesting, differences in the density of standing of corn during various methods of tillage were also noted. So, on plowing under the conditions of herbicide protection, the density was high and was in the range of 72,9–7,2 thousand units. / Ha, while for small disk – 72,3–72,6 thousand units./ha. Herbicidal protection options ensured the death of weeds by 89–100 % within 30 days after their application. At the time of harvesting the crop, the decrease in the number of weeds compared to the untreated areas amounted to 71–98 %. The most effective was the double application of roundup max 2,4 l/ha in phases 3 and 8 of the leaves in corn. The highest yield of corn grain was obtained due to the double use of the herbicide roundup max at a rate of 2,4 l/ha. In the case of police processing, the collection was 9,4 t/ha, and for small-scale processing, it was 9,2 t/ha. Key words: corn, soil cultivation, weeds, herbicides, efficiency, productivity.

Wear Analysis of Compression Ignition Engine using Mesua ferea linn Methyl Eseter

As the standard of living is increasing day by day, the demand for energy consumption is also increasing due to the increasing population and expanding urbanization.At the same time,the whole world is aware about the depletion of petroleum reserves and its impact on environment pollution through exhaust emissions which has become a major threat to the whole world, so to deal with this there is an urgent need of suitable alternative fuels for use in diesel engine. Biodiesel is a suitable alternative fuel which is generally produced from renewable biological resources like vegetable oil and animal fats. It is biodegradable , non toxic, has lower emissions profile and at the same time environment friendly. In this study, biodiesel is prepared using mesua ferea linn(MFL)seed oil by transterification process. Two similar engines were operated for long turm endurance test using optimum biodiesel blend and petroleum-diesel oil, respectively. Atomic absorption spectroscopy (AAS) was used to check the wear debris concentration in lubricating oil samples which were drawn from both the engines after a fixed interval of time. Biodiesel operated engine showed lower wear debris concentration as compared to diesel operated engine. Scanning electron microscopy( SEM) showed lower damage of small disk of piston ring when operated with 20% biodiesel fuel, which revealed the better lubricity of biodiesel fuel. Also, carbon deposition of various parts like fuel injector, piston head were found to be lower in biodiesel used engine than that of diesel used engine.

A Compact Integrated Small Disk Monopole Antenna with DGS for Wireless Applications

The structure of a compact Micro strip feed circular monopole antenna working in the frequency range of (2.5GHz-4GHz) and wideband of frequency ranging from 4.9GHz to 19.93GHz is proposed in this paper. Using a circular radiating monopole with terrible ground wideband frequency operation is possible. Two frequency bands can be accomplished by separating the middle part of the patch and further engraving a circular arc r=4.4 and a loss tangent of 0.02 was utilized to realize and simulate this antenna. It can be operated in both the frequency bands 2.5-4GHz and 4.9-19.93GHz [wideband] possessing less than -10dB reflection coefficient. The whole WB and also in the low-frequency band as mentioned above shows a sturdy radiation pattern.

Did Tim Paint a Vermeer?

Tim’s Vermeer is a recent documentary feature film following engineer and self-described non-artist Tim Jenison’s extensive efforts to “paint a Vermeer” by means of a novel optical telescope and mirror-comparator procedure. His efforts were inspired by the controversial claim that some Western painters as early as 1420 secretly built optical devices and traced passages in projected images during the execution of some of their works, thereby achieving a novel and compelling “optical look.” The authors examine the proposed telescope optics in historical perspective, the particular visual evidence adduced in support of the comparator hypothesis, and the difficulty and efficacy of the mirror-comparator procedure as revealed by an independent artist/copyist’s attempts to replicate the procedure. Specifically, the authors find that the luminance gradient along the rear wall in the duplicate painting is far from being rare, difficult, or even “impossible” to achieve as proponents claimed; in fact, such gradients appear in numerous Old Master paintings that show no ancillary evidence of having been executed with optics. There is indeed a slight bowing of a single contour in the Vermeer original, which one would normally expect to be straight; however, the optical explanation for this bowing implies that numerous other lines would be similarly bowed, but in fact all are straight. The proposed method does not explain some of the most compelling “optical” evidence in Vermeer’s works such as the small disk-shaped highlights, which appear like the blur spots that arise in an out-of-focus projected image. Likewise, the comparator-based explanations for the presence of pinprick holes at central vanishing points and the presence of underdrawings and pentimenti in several of Vermeer’s works have more plausible non-optical explanations. Finally, an independent experimental attempt to replicate the procedure fails overall to provide support for the telescope claim. In light of these considerations and evidence, the authors conclude that it is extremely unlikely that Vermeer used the proposed mirror-comparator procedure.