An FEA material strength modelling of a coated engine piston

Engine pistons are subjected to high gas pressure force on the crown. Such compressive force, helps the piston to gain inertia for reciprocation. But suitable materials are required to sustain higher temperature(500 °C) and pressure (120 bar) environments in engine. Aluminum based alloy or cast iron are selected for such application. To enhance material life, sometimes coating is done to reduce the effect of thermal and stress behavior. This study aims to investigate a combination effect of coating and geometrical modification on the material strength of an engine piston. A piston head, with a bowl shape was analyzed by finite element technique, considering the whole piston is coated with TiSiCN thin layer. The analysis was developed to predict the material strength of two types of pistons: uncoated flat crown and a TiSiCN coated bowl on the crown. A comparative analysis was carried out to summarize the benefits of such modifications in a piston. The result showed a 33.96% reduction on stress level and 11.9% reduction in deformation achieved due to such coating process

A Large-scale Analysis of the Marketplace Characteristics in Fiverr

Crowdsourcing platforms have become quite popular due to the increasing demand of human computation-based tasks. Though the crowdsourcing systems are primarily demand-driven like MTurk, supply-driven marketplaces are becoming increasingly popular. Fiverr is a fast growing supply-driven marketplace where the sellers post micro-tasks (gigs) and users purchase them for prices as low as $5. In this paper, we study the Fiverr platform as a unique marketplace and characterize the sellers, buyers and the interactions among them. We find that sellers are more appeasing in their interactions and try to woo their buyers into buying their gigs. There are many small tightly-knit communities existing in the seller-seller network who support each other. We also study Fiverr as a seller-driven marketplace in terms of sales, churn rates, competitiveness among various subcategories etc. and observe that while there are certain similarities with common marketplaces there are also many differences

Discovery of Magnetospheric Interactions in the Doubly-Magnetic Hot Binary ϵ\epsilon Lupi

Magnetic fields are extremely rare in close, hot binaries, with only 1.5\% of such systems known to contain a magnetic star. The eccentric $\epsilon$ Lupi system stands out in this population as the only close binary in which both stars are known to be magnetic. We report the discovery of strong, variable radio emission from $\epsilon$ Lupi using the upgraded Giant Metrewave Radio Telescope (uGMRT) and the MeerKAT radio telescope.The light curve exhibits striking, unique characteristics including sharp, high-amplitude pulses that repeat with the orbital period, with the brightest enhancement occurring near periastron. The characteristics of the light curve point to variable levels of magnetic reconnection throughout the orbital cycle, making $\epsilon$ Lupi the first known high-mass, main sequence binary embedded in an interacting magnetosphere. We also present a previously unreported enhancement in the X-ray light curve obtained from archival XMM-Newton data. The stability of the components' fossil magnetic fields, the firm characterization of their relatively simple configurations, and the short orbital period of the system make $\epsilon$ Lupi an ideal target to study the physics of magnetospheric interactions. This system may thus help us to illuminate the exotic plasma physics of other magnetically interacting systems such as moon-planet, planet-star, and star-star systems including T Tauri binaries, RS CVn systems, and neutron star binaries.Comment: Accepted for publication in MNRAS, 16 pages, 12 figure

COEXISTENCE OF POLYMORPHISM IN FECUNDITY GENES BMPR 1B AND GDF 9 OF INDIAN KENDRAPADA SHEEP

Present study was carried out to find out the status of mutations in three fecundity genes i.e. growth differentiation factor 9 (GDF9/FecG), bone morphogenetic protein 15 (BMP15/FecX) and bone morphogenetic protein receptor (BMPR1B/FecB) in Kendrapada sheep, the second most prolific sheep breed of India after Garole. Kendrapada ewes (n=85) were genotyped by Tetra-primer amplification refractory mutation system-PCR and a total of eleven SNP points over these three candidate fecundity genes (one point on FecB and five points each on BMP15 and GDF9) were assessed. Out of eleven, two SNP points, viz. FecB and G4 of GDF9 were found to be polymorphic in this breed. In this sheep breed average litter size of the ewes with non-carriers, heterozygous carrier and homozygous carrier of FecB locus mutation were 1.61, 1.80 and 2.06 respectively. G4 point of the GDF9 gene was also polymorphic with average litter size of noncarriers, heterozygous carrier and homozygous carrier ewes were 1.63, 2.00 and 1.91 respectively. This study establishes Kendrapada sheep as the sixth sheep breed after Belclare/Cambridge, Lacaune, Small-tailed Han, Garole and Bayanbulak sheep, where coexisting polymorphism has been found in two different fecundity genes (BMPRIB and GDF9 genes)

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Performance and Operation of the CMS Electromagnetic Calorimeter

The operation and general performance of the CMS electromagnetic calorimeter using cosmic-ray muons are described. These muons were recorded after the closure of the CMS detector in late 2008. The calorimeter is made of lead tungstate crystals and the overall status of the 75848 channels corresponding to the barrel and endcap detectors is reported. The stability of crucial operational parameters, such as high voltage, temperature and electronic noise, is summarised and the performance of the light monitoring system is presented

Calibration of the CMS Drift Tube Chambers and Measurement of the Drift Velocity with Cosmic Rays

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CMS Data Processing Workflows during an Extended Cosmic Ray Run

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Aligning the CMS Muon Chambers with the Muon Alignment System during an Extended Cosmic Ray Run

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