strategies for modelling and optimization of bi stable composite laminates actuated by embedded shape memory alloy wires

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analysis of bistable composite laminate with embedded sma actuators

Abstract The present work is aimed at the development of a finite element model of a composite laminate, to evaluate the possibility to snap between equilibrium configurations by means of shape memory alloy (SMA) wires. The underlying idea is to potentially take advantage of structures which possess multiple equilibrium configurations that can be achieved with a small energy input. Therefore, unsymmetric composite laminates that exhibit bistable response to actuation force are considered. Embedded SMA wires will provide the actuation force by virtue of Shape-Memory Effect i.e. restoring the original shape of a plastically deformed SMA wire by heating it. The Shape-Memory Effect is modelled in a simplified way using the Effective Coefficient of Thermal Expansion concept

Comparative Study of Pure Mg and AZ91D as Sacrificial Anodes for Reinforced Cement Concrete Structures in Chloride Atmosphere

Comparative study of the corrosion behavior of pure Magnesium and AZ91D anodes in reinforced cement concrete was undertaken in the present work. The steel reinforcements were kept in contact with these anodes electrochemically in chloride atmosphere and the half-cell potential drop was observed. Bare steel reinforcements were tied to the anodes and were also kept in high chloride atmosphere to test the mechanical properties. The yield stress and ultimate tensile stress were found to decrease by approximately 50MPa while the reduction in percentage elongation is approximately 25% for reinforcements tied to AZ91D and pure Mg at the end of 80 days compared to fresh steel reinforcement. The rate of corrosion of pure Mg was reportedly slightly higher compared to AZ91D due to the presence of inter-metallics as inferred through micro-graphs

Design and Development of Scissor Type Car Lifter

Vehicles have always been heavy and requiring regular repairs. That was the necessity behind car lifts invention. These days, car lifts are an integral part of many garages and repair shops but its applications are not limited to that, theyre also used to raise vehicles for storage in places where ramps are inconvenient or if there are space restrictions. The car lift we are working on is used for raising loaded mini-trucks. The main objective of our project is to design and analyze car lift to fit the given parameters and for doing that, the history and types of car lifts are studied, several research papers are referred to. In case of our lift, it had to be more stable and have a higher capacity so as to lift loaded mini-trucks. The project uses Solid works for design and ANSYS for analysis of the CAD model of the lift. After the design is analyzed, the parts are ordered and the lift is assembled. There were a lot of problems we faced during the process and design and construction details were modified accordingly

A critical assessment on the effect of nano-titanium dioxide on the properties of concrete

Nedavni napredak nanotehnologije u raznim područjima izuzetno je obećavajuće za rješavanje širokog spektra problema. U istraživanjima i izumima se pokazalo da nanotehnologija poboljšava učinkovitost konvencionalnih građevnih materijala kao što je beton. Brojne vrste nanočestica, kao što je nano titanijev dioksid, koriste se za značajno poboljšanje učinkovitosti, dugotrajnosti i održivosti betona. Ovaj rad sažima prethodna istraživanja o učinku nanotitanijeva dioksida na različita svojstva, uključujući toplinu hidratacije, obradivost, vrijeme vezivanja, kemijsko skupljanje, mehaničku čvrstoću, otpornost na abraziju, vatrootpornost i otpornost na smrzavanje/odmrzavanje. Vrijednosti upijanje vode, penetracija klorida i propusnosti su male u konvencionalnim sustavima običnog ili mješovitog cementa. Osim toga, u ovom istraživanju matrica koja sadrži nanotitanijev dioksid uspoređuje se s matricom koja sadrži druge nanočestice. Građevinski inženjeri mogu koristiti ovaj opis kao izvor podataka.Recent advances in nanotechnology in various fields demonstrate tremendous promise for resolving a wide variety of problems. Nanotechnology has been shown to improve the efficiency of conventional building materials such as concrete. Numerous types of nanoparticles, such as nano-titanium dioxide, are being used to significantly improve the efficiency, longevity, and sustainability of concrete. This paper summarises prior research on the effect of nano-titanium dioxide on a variety of properties, including heat of hydration, workability, setting time, chemical shrinkage, mechanical strength, abrasion resistance, fire resistance, and freeze/thaw resistance. Water absorption, chloride penetration, and permeability are all low in conventional plain or blended cement systems. Additionally, the matrix containing nano-titanium dioxide is compared in this study to a matrix containing other nanoparticles. Civil engineers can use this paper as a quick reference

Feasibility studies for the measurement of time-like proton electromagnetic form factors from p¯ p→ μ+μ- at P ¯ ANDA at FAIR

This paper reports on Monte Carlo simulation results for future measurements of the moduli of time-like proton electromagnetic form factors, | GE| and | GM| , using the p¯ p→ μ+μ- reaction at P ¯ ANDA (FAIR). The electromagnetic form factors are fundamental quantities parameterizing the electric and magnetic structure of hadrons. This work estimates the statistical and total accuracy with which the form factors can be measured at P ¯ ANDA , using an analysis of simulated data within the PandaRoot software framework. The most crucial background channel is p¯ p→ π+π-, due to the very similar behavior of muons and pions in the detector. The suppression factors are evaluated for this and all other relevant background channels at different values of antiproton beam momentum. The signal/background separation is based on a multivariate analysis, using the Boosted Decision Trees method. An expected background subtraction is included in this study, based on realistic angular distributions of the background contribution. Systematic uncertainties are considered and the relative total uncertainties of the form factor measurements are presented

The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients

Global estimates on the number of people blind or visually impaired by cataract: a meta-analysis from 2000 to 2020

Background: To estimate global and regional trends from 2000 to 2020 of the number of persons visually impaired by cataract and their proportion of the total number of vision-impaired individuals. Methods: A systematic review and meta-analysis of published population studies and gray literature from 2000 to 2020 was carried out to estimate global and regional trends. We developed prevalence estimates based on modeled distance visual impairment and blindness due to cataract, producing location-, year-, age-, and sex-specific estimates of moderate to severe vision impairment (MSVI presenting visual acuity &lt;6/18, ≥3/60) and blindness (presenting visual acuity &lt;3/60). Estimates are age-standardized using the GBD standard population. Results: In 2020, among overall (all ages) 43.3 million blind and 295 million with MSVI, 17.0 million (39.6%) people were blind and 83.5 million (28.3%) had MSVI due to cataract blind 60% female, MSVI 59% female. From 1990 to 2020, the count of persons blind (MSVI) due to cataract increased by 29.7%(93.1%) whereas the age-standardized global prevalence of cataract-related blindness improved by −27.5% and MSVI increased by 7.2%. The contribution of cataract to the age-standardized prevalence of blindness exceeded the global figure only in South Asia (62.9%) and Southeast Asia and Oceania (47.9%). Conclusions: The number of people blind and with MSVI due to cataract has risen over the past 30 years, despite a decrease in the age-standardized prevalence of cataract. This indicates that cataract treatment programs have been beneficial, but population growth and aging have outpaced their impact. Growing numbers of cataract blind indicate that more, better-directed, resources are needed to increase global capacity for cataract surgery.</p

AI is a viable alternative to high throughput screening: a 318-target study

: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

Precision resonance energy scans with the PANDA experiment at FAIR: Sensitivity study for width and line shape measurements of the X(3872)

This paper summarises a comprehensive Monte Carlo simulation study for precision resonance energy scan measurements. Apart from the proof of principle for natural width and line shape measurements of very narrow resonances with PANDA, the achievable sensitivities are quantified for the concrete example of the charmonium-like X(3872) state discussed to be exotic, and for a larger parameter space of various assumed signal cross-sections, input widths and luminosity combinations. PANDA is the only experiment that will be able to perform precision resonance energy scans of such narrow states with quantum numbers of spin and parities that differ from J P C = 1 - -