1,804 research outputs found
Study of the mechanical properties of a ceramics of orthopedic and dental use
The study of the preparation of ceramics is consisted in sintering a hardened cement, wich is composed of mixture of three calcium phosphates : tetracalcium phosphate (Ca4(PO4)2O), -tricalcium phosphate (-Ca3(PO4)2) and monocalcium phosphate (Ca(H2PO4)2.H2O).After wetting, the cement evolved towards an apatitic phase while hardening. To check the effect of certain factors on the resulting ceramics, a complete central composite design of four variables (liquid/solid ratio, stoichiometric coefficient of
monocalcium phosphate, rate of increase in temperature and duration of landing of termpertaure) was set
up. The equation of the model and optimal conditions were defined
A disaster-resilient multi-content optical datacenter network architecture
Cloud services based on datacenter networks are becoming very important. Optical networks are well suited to meet the demands set by the high volume of traffic between datacenters, given their high bandwidth and low-latency characteristics. In such networks, path protection against network failures is generally ensured by providing a backup path to the same destination, which is link-disjoint to the primary path. This protection fails to protect against disasters covering an area which disrupts both primary and backup resources. Also, content/service protection is a fundamental problem in datacenter networks, as the failure of a single datacenter should not cause the disappearance of a specific content/service from the network. Content placement, routing and protection of paths and content are closely related to one another, so the interaction among these should be studied together. In this work, we propose an integrated ILP formulation to design an optical datacenter network, which solves all the above-mentioned problems simultaneously. We show that our disaster protection scheme exploiting anycasting provides more protection, but uses less capacity, than dedicated single-link protection. We also show that a reasonable number of datacenters and selective content replicas with intelligent network design can provide survivability to disasters while supporting user demands
Director networks and informed traders
We provide evidence that sophisticated investors like short sellers, option traders, and financial institutions are more informed when trading stocks of companies with more connected board members. For firms with large director networks, the annualized return difference between the highest and lowest quintile of informed trading ranges from 4% to 7.2% compared to the same return difference in firms with less connected directors. Sophisticated investors better predict outcomes of upcoming earnings surprises and firm-specific news sentiment for companies with more connected directors. Changes in board connectedness are positively associated with changes in measures of adverse selection
Vision-based sensor for three-dimensional vibrational motion detection in biological cell injection
Intracytoplasmic sperm injection (ICSI) is an infertility treatment where a single sperm is immobilised and injected into the egg using a glass injection pipette. Minimising vibration in three orthogonal axes is essential to have precise injector motion and full control during the egg injection procedure. Vibration displacement sensing using physical sensors in ICSI operation is challenging since the sensor interfacing is not practically feasible. This study proposes a non-invasive technique to measure the three-dimensional vibrational motion of the injection pipette by a single microscope camera during egg injection. The contrast-limited adaptive histogram equalization (CHALE) method and blob analyses technique were employed to measure the vibration displacement in axial and lateral axes, while the actual dimension of the focal axis was directly measured using the Brenner gradient algorithm as a focus measurement algorithm. The proposed algorithm operates between the magnifications range of 4Ă to 40Ă with a resolution of half a pixel. Experiments using the proposed vision-based algorithm were conducted to measure and verify the vibration displacement in axial and lateral axes at various magnifications. The results were compared against manual procedures and the differences in measurements were up to 2% among all magnifications. Additionally, the effect of injection speed on lateral vibration displacement was measured experimentally and was used to determine the values for egg deformation, force fluctuation, and penetration force. It was shown that increases in injection speed significantly increases the lateral vibration displacement of the injection pipette by as much as 54%. It has been demonstrated successfully that visual sensing has played a key role in identifying the limitation of the egg injection speed created by lateral vibration displacement of the injection pipette tip
Rapid extraction of volatile compounds from Citrus fruits using a microwave dry distillation
Three different extraction methods were used for a comparative study of essential oil (EO) from fresh Citrus peels: Traditional hydrodistillation (HD), cold pressing (CP) and innovative microwave âdryâ distillation or microwave-accelerated distillation (MAD). The microwave process offers significant advantages over conventional alternatives, viz. shorter distillation period (30 min vs. 3 h for hydrodistillation and 1 h for cold pressing); better yields (0.24% vs. 0.21% for HD and 0.054% for CP); environmental impact (energy charge is noticeably superior for performing HD and for mechanical motors (CP) than that necessary for quick MAD assay); cleaner features (as no remains creation and no solvent or water used); raises antibacterial properties ; and offers a more precious EO (with high amounts of oxygenated compounds).Keywords: Microwave extraction; Hydrodistillation; Cold pressing; Essential oil; Citru
Heavy metal resistance of microorganisms from petroleum hydrocarbon contaminated soils located in Mersin, Turkey
European Biotechnology Congress -- MAY 25-27, 2017 -- Dubrovnik, CROATIAWOS: 000413585400193âŚAhi Evran Univ. BAP [PYO-Fen.4003/2.14.009 (2015)]This work was supported in part by a grant from Ahi Evran Univ. BAP No: PYO-Fen.4003/2.14.009 (2015)
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