Miracle-dz/UniFAR-FTUs huggingface dataset:
Parametric Study of Turbine Blade Internal Cooling and Film Cooling

Parametric Study of Turbine Blade Internal Cooling and Film Cooling . (August 2010) Akhilesh Prabhakar Rallabandi, B. Tech, Indian Institute of Technology, Madras; M. Tech, Indian Institute of Technology, Madras Chair of Advisory Committee: Dr. Je-Chin Han Gas turbine engines are extensively used in the aviation and power generation industries. They are used as topping cycles in combined cycle power plants, or as stand alone power generation units. Gains in thermodynamic efficiency can be realized by increasing the turbine inlet temperatures. Since modern turbine inlet temperatures exceed the melting point of the constituent superalloys, it is necessary to provide an aggressive cooling system. Relatively cool air, ducted from the compressor of the engine is used to remove heat from the hot turbine blade. This air flows through passages in the hollow blade (internal cooling), and is also ejected onto the surface of the blade to form an insulating film (film cooling). Modern land-based gas turbine engines use high Reynolds number internal flow to cool their internal passages. The first part of this study focuses on experiments pertaining to passages with Reynolds numbers of up to 400,000. Common turbulator designs (45degree parallel sharp-edged and round-edged) ribs are studied. Older correlations are found to require corrections in order to be valid in the high Reynolds number parameter space. The effect of rotation on heat transfer in a typical three-pass serpentine channel is studied using a computational model with near-wall refinement. Results from this computational study indicate that the hub experiences abnormally high heat transfer
Innovative performance-based design of slope stabilizing piles for a railway embankment

The paper presents a simplified displacement-based approach for the design of a slope stabilising system. On the top of the slope, a railway ballasted track induces repeated dynamic loads on the subgrade soil, that, in conjunction with other cyclic environmental loads (seasonal temperature and soil moisture variation) induce a progressive accumulation of soil displacements, despite the safety factors for the slope, if computed by means of traditional limit equilibrium methods, are all larger than one. The design procedure started then from the analysis of preliminary (pre-operam) monitoring data, in order to define the shape and amplitude of the soil displacement field, by interpreting them within a viscoplastic constitutive framework. This allowed to conveniently optimise the slope stabilising system (consisting in FRC piles connected to each other by means of a precast FRC beam and reinforced by pre-stressed ground anchors) with the aim of reducing the soil displacement rates below a prescribed threshold. The focus of the work, rather than presenting advanced constitutive or numerical simulations, is on the design approach, which allows the designer to get a reliable and safe design solution, even in lack of rich and sophisticated site characterisation, as it is often the case in real applications.
The Role of Stochastic Forcing on the Behavior of Thermohaline Circulation

The nonlinear nature of the climate system suggests that its reactions to unexpected perturbations could be different from the expected ones. In nonlinear science it is recognized as a promising paradigm that stochastic fluctuations can generate order or other counterintuitive effects. Thus, noise sources, adequately coupled to a nonlinear system, may give rise to a rich new phenomenology not present in a deterministic noiseless scenario. In this review we focus attention on thermohaline circulation (THC). THC presents two modes of operation; one state shows active THC and the other inactive. Previous episodes of transitions between both states of THC observed in paleoclimatic records and the influence of this circulation on climate have resulted in detailed investigations on the dynamics of the THC. A weakening or a collapse of this current could trigger the onset of a new Younger Dryas. In this review the introduction of stochastic forcing in key parameters, both in a simple box model and in an earth model of intermediate complexity, provokes a weakening and even a shutdown of the THC. The consequences of this weakening are observed in different variables. The surface air temperature and the sea surface temperature are dominated by cooling of the Northern Hemisphere. Changes in the position of the Intertropical Convergence Zone and in precipitation are observed. There is also an intensification of the North Atlantic Oscillation values during winter. These results reinforce the necessity to consider stochastic sources in climate models to improve our understanding of the climate.
Treatment to suppression of focal lesions on positron emission tomography-computed tomography is a therapeutic goal in newly diagnosed multiple myeloma

Fluorine-18 fluorodeoxyglucose positron emission tomography with computed tomography attenuation correction (PET-CT) in myeloma can detect and enumerate focal lesions by the quantitative characterization of metabolic activity. The aim of this study was to determine the prognostic significance of the suppression of PET-CT activity at a number of time points post therapy initiation: day 7, post induction, post transplant, and at maintenance therapy. As part of the TT4-6 trial series, 596 patients underwent baseline PET-CT and were evaluated serially during their disease course using peak standardized uptake values above background red marrow signal. We demonstrate that the presence of more than 3 focal lesions at presentation identifies a group of patients with an adverse progression-free survival and overall survival. At day 7 of therapy, patients with complete focal lesion signal suppression revert to the same prognosis as those with no lesions at diagnosis. At later time points, the continued suppression of signal remains prognostically important. We conclude that for newly diagnosed patients with focal lesions, treatment until these lesions are suppressed is an important therapeutic goal as the prognosis of these patients is the same as those without lesions at diagnosis. (clinicaltrials.gov identifiers: 00734877, 02128230, 00869232, 00871013).
Rapid conversion of an oceanic spreading center to a subduction zone inferred from high-precision geochronology

Significance Subduction, the process by which tectonic plates sink into the mantle, is a fundamental tectonic process on Earth, yet the question of where and how new subduction zones form remains a matter of debate. In this study, we find that a divergent plate boundary, where two plates move apart, was forcefully and rapidly turned into a convergent boundary where one plate eventually began subducting. This finding is surprising because, although the plate material at a divergent boundary is weak, it is also buoyant and resists subduction. This study suggests that buoyant, but weak, plate material at a divergent boundary can be forced to converge until eventually older and denser plate material enters the nascent subduction zone, which then becomes self-sustaining. Where and how subduction zones initiate is a fundamental tectonic problem, yet there are few well-constrained geologic tests that address the tectonic settings and dynamics of the process. Numerical modeling has shown that oceanic spreading centers are some of the weakest parts of the plate tectonic system [Gurnis M, Hall C, Lavier L (2004) Geochem Geophys Geosys 5:Q07001], but previous studies have not favored them for subduction initiation because of the positive buoyancy of young lithosphere. Instead, other weak zones, such as fracture zones, have been invoked. Because these models differ in terms of the ages of crust that are juxtaposed at the site of subduction initiation, they can be tested by dating the protoliths of metamorphosed oceanic crust that is formed by underthrusting at the beginning of subduction and comparing that age with the age of the overlying lithosphere and the timing of subduction initiation itself. In the western Philippines, we find that oceanic crust was less than ∼1 My old when it was underthrust and metamorphosed at the onset of subduction in Palawan, Philippines, implying forced subduction initiation at a spreading center. This result shows that young and positively buoyant, but weak, lithosphere was the preferred site for subduction nucleation despite the proximity of other potential weak zones with older, denser lithosphere and that plate motion rapidly changed from divergence to convergence.
Chemical profiling of Centella asiatica under different extraction solvents and its antibacterial activity, antioxidant activity

Centella asiatica (L) urban, synonym Hydrocotyle asiatica, is found almost all over the world. This plant is famous in Ayurvedic medicine and used in the management of central nervous system, skin and gastrointestinal disorder. Thus this research had been done to evaluate the effect of solvent extraction (Ethanol, Chloroform and Hexane) of C. asiatica on chemical profile, antioxidant activity and antibacterial activity against some foodborne pathogens. The result showed that all solvents (ethanol, chloroform and hexane) used in extraction showed antibacterial activity against Salmonella enterica Typhimurium U302, S. enterica Enteritidis, S. enterica 4,5,12:I human (US clone), Bacillus cereus and B. subtilis at 50mg/ml concentration. In antioxidant part, ethanolic extract gave highest phenolic content and FRAP value. The results also showed that different extraction solvent gave different chemical profile. Hexane extract C. asiatica showed lowest in both antibacterial and antioxidant activity. Ethanolic and chloroform extract of C. asiatica showed promising potential in both antibacterial and antioxidant activity.
Bat detective—Deep learning tools for bat acoustic signal detection

Passive acoustic sensing has emerged as a powerful tool for quantifying anthropogenic impacts on biodiversity, especially for echolocating bat species. To better assess bat population trends there is a critical need for accurate, reliable, and open source tools that allow the detection and classification of bat calls in large collections of audio recordings. The majority of existing tools are commercial or have focused on the species classification task, neglecting the important problem of first localizing echolocation calls in audio which is particularly problematic in noisy recordings. We developed a convolutional neural network (CNN) based open-source pipeline for detecting ultrasonic, full-spectrum, search-phase calls produced by echolocating bats (BatDetect). Our deep learning algorithms (CNN FULL and CNN FAST) were trained on full-spectrum ultrasonic audio collected along road-transects across Romania and Bulgaria by citizen scientists as part of the iBats programme and labelled by users of www.batdetective. org. We compared the performance of our system to other algorithms and commercial systems on expert verified test datasets recorded from different sensors and countries. As an example application, we ran our detection pipeline on iBats monitoring data collected over five years from Jersey (UK), and compared results to a widely-used commercial system. Here, we show that both CNNFULL and CNNFAST deep learning algorithms have a higher detection performance (average precision, and recall) of search-phase echolocation calls with our test sets, when compared to other existing algorithms and commercial systems tested. Precision scores for commercial systems were reasonably good across all test datasets (>0.7), but this was at the expense of recall rates. In particular, our deep learning approaches were better at detecting calls in road-transect data, which contained more noisy recordings. Our comparison of CNNFULL and CNNFAST algorithms was favourable, although CNNFAST had a slightly poorer performance, displaying a trade-off between speed and accuracy. Our example monitoring application demonstrated that our open-source, fully automatic, BatDetect CNNFAST pipeline does as well or better compared to a commercial system with manual verification previously used to analyse monitoring data. We show that it is possible to both accurately and automatically detect bat search-phase echolocation calls, particularly from noisy audio recordings. Our detection pipeline enables the automatic detection and monitoring of bat populations, and further facilitates their use as indicator species on a large scale, particularly when combined with automatic species identification. We release our system and datasets to encourage future progress and transparency.
Rotational foam molding of polypropylene with control of melt strength

Polypropylene (PP) has not been used extensively in rotational foam molding because it has been traditionally considered as nonfavorable for foaming applications because of its relatively weak melt strength and melt elasticity at elevated temperatures. However, because of the unique end-use properties of PP, PP foams have recently grown in importance. An experimental study was conducted to identify feasible processing strategies for producing PP foams with satisfactory morphologies in dry-blending-based rotational foam molding. The obtained results revealed that cell coalescence plays a key role in the production of PP foams in rotational foam molding. If it is efficiently suppressed, the cell morphology of the PP foams improves dramatically. To suppress cell coalescence, it would be necessary to preserve the melt strength of PP during processing. One way of doing this is maintaining the temperature of the PP melt as low as possible. This can be accomplished by either lowering the decomposition temperature of the chemical blowing agent by using an activator such as zinc oxide and/or reducing the temperature of the oven. © 2003 Wiley Periodicals, Inc. Adv Polym Techn 22: 280–296, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.10056
An Investigation on Quality Characterization and Magnitude of Pollution Implications with Textile Dyeing Industries' Effluents using Bleaching Powder

This paper describes the outcomes of an investigation on the harmful effects of waste water effluents coming from textile dying industries. A comprehensive study was accomplished through treatment of sample wastes from nine dyeing industries around Gazipur city. Because of high molecular weight and complex chemical structures showing low level of biodegradability, direct deposition of these effluents into sewage networks produce disturbances in treatment processes and exert pollution loads on water bodies. Emphasis was given on the oxidation process for removal of color and other pollution loads. The color removal efficiency was studied by adding different amount of oxidizing agent. Specifically, bleaching powder was used as an oxidizing agent and the parameters considered in this study was pH value, turbidity, total suspended solids (TSS), chemical oxygen demand(COD), and biochemical oxygen demand(BOD). At an optimum level of pH 8.8, the doses of oxidizing agent were determined by batch study. Using the dose of oxidizing agent 500 mg/l, the color removal efficiency of waste water was found to be 90%. It was also seen that the pollution loads (BOD5, COD, and TSS etc.) were reduced to a tolerable limit by using bleaching powder in oxidation process. The color decreased after treatment with bleaching powder consequently increases the total solid in the final effluents. The effects of using various concentrations of bleaching powder on TSS, BOD and COD were studied which have been presented in this paper. The study was focused on the pollution implications of effluents from textile industries around the city, because of the risk of human exposure and environmental degradation by these massive discharge effluents.
Utilisation of warm-mix asphalt technology to improve bituminous mixtures containing reclaimed asphalt pavement

Pavement recycling is a logical way to conserve our diminishing supply of construction materials and reduce the cost of preserving our existing pavement. In this research road recycling was discussed briefly through a number of lab tests using Marshall test, Indirect Tensile (IDT) test and Loaded Wheel Track Rutting (LWTR) test on Reclaimed Asphalt Pavement (RAP). These tests were conducted to justify the properties and analyse the strength of RAP mixtures containing Sasobit material, which is considered a Warm-mix Asphalt Wax (WMAW) to improve the characteristics of the mix, and reduce the standard viscosity temperature, bitumen amount and compaction temperature. The study used bitumen penetration grade (PG) (60/70) produced by local Sues factories. The bituminous layer used was the wearing surface layer. Samples for RAP were taken from Cairo–Fayoum desert road. The virgin materials were gathered and tested according to Egyptian specifications. To achieve this goal, several samples were considered for Marshall test and IDT test using different ratios of RAP (15%, 20%, 30%, 40%, 50%, 60%, 70%, 80% and 100%) with different amounts of WMAW (1.5% and 3%) and taking different compaction temperatures (115, 125 and 135°C). As for the LWTR test, the samples were made with 15%, 20%, 60% and 80% RAP. The results were compared to the standard mix (no WMAW at 135°C compaction temperature). Laboratory results showed that the use of RAP with WMAW resulted in improvement in compactability, increase in the softening point, reduction in penetration and increase in resistance to rutting. In addition, Analysis of Variance (ANOVA) using SPSS software was also used to compare the means of results for stability and air voids of Marshall test, IDT test and LWTR test to that of the standard mix. The ANOVA analysis showed significance in results when using the WMAW, and the most significant results were obtained when using 1.5% WMAW additive at a temperature of 125°C with 20% RAP mixture.
Seasonal Impact of Adjacency Effects on Ocean Color Radiometry at the AAOT Validation Site

The seasonal impact of adjacency effects (AE) on satellite ocean color data at visible and near-infrared (NIR) wavelengths by the Sea-Viewing Wide Field-of-View Sensor, the Moderate Resolution Imaging Spectroradiometer onboard the Aqua platform (MODISA), the Medium Resolution Imaging Spectrometer, the Ocean and Land Color Instrument, the Operational Land Imager (OLI), and the MultiSpectral Imagery (MSI) was theoretically evaluated at a validation site in the northern Adriatic Sea. The analysis made use of comprehensive simulations accounting for multiple scattering, sea surface roughness, sensor viewing geometry, actual coastline, typical and extreme atmospheric conditions, and the seasonal variability of solar illumination and, land and water optical properties. Results, obtained by relying on the normalization of the radiometric sensitivity of each sensor to the same input radiance, show that the spectral and seasonal impacts of AE considerably vary among sensors. AE significantly exceed the radiometric sensitivity of MSI at its sole blue band in winter, whereas they significantly outdo the noise threshold of OLI and MODISA high-resolution data exclusively in the NIR in summer. Conversely, for all other sensors and for MODISA low-resolution data, AE are particularly significant at NIR bands between March and October and at the blue–green bands in winter.
Familial aggregation of rheumatoid arthritis and co-aggregation of autoimmune diseases in affected families: a nationwide population-based study

Objective The aim was to estimate familial relative risk (RR) for RA and other autoimmune diseases and the genetic contribution to RA phenotypic variance (heritability). Methods This study used the Taiwan National Health Insurance Research Database to identify all National Health Insurance registered beneficiaries (n = 23 658 577) in 2010; among them, 37 482 individuals had RA. We estimated familial RRs and 95% CIs of RA and other autoimmune diseases using marginal Cox proportional models and heritability of RA using a threshold liability model. Results The RR (95% CI) for RA was 328.27 (135.95, 795.63) for twins of RA patients; 11.97 (8.68, 16.52) for siblings; 4.86 (4.16, 5.67) for parents; 4.65 (3.92, 5.50) for offspring; and 2.32 (1.83, 2.95) for spouses. Using a threshold liability model, we estimated that familial transmission was 59.4% (95% CI: 50.3, 69.5%) and that heritability was 43.5% (33.9, 54.1%). The RR (95% CI) in individuals with a first-degree relative with RA was 2.91 (2.49, 3.42) for SLE; 2.92 (1.62, 5.25) for SSc; 3.13 (2.50, 3.93) for primary SS; 0.95 (0.36, 2.51) for idiopathic inflammatory myositis; 1.96 (1.54, 2.48) for type 1 diabetes mellitus; 3.32 (1.82, 5.95) for multiple sclerosis; 1.31 (1.31, 2.43) for IBD; 2.76 (2.46, 3.10) for AS; and 1.65 (1.54, 1.77) for psoriasis. Conclusion The risks of RA and other autoimmune diseases increased in individuals with an RA family history. Approximately two-thirds of RA phenotypic variation is explained by familial factors.
Geographical sampling bias in a large distributional database and its effects on species richness–environment models

Recent advances in the availability of species distributional and high‐resolution environmental data have facilitated the investigation of species richness–environment relationships. However, even exhaustive distributional databases are prone to geographical sampling bias. We aim to quantify the inventory incompleteness of vascular plant data across 2377 Chinese counties and to test whether inventory incompleteness affects the analysis of richness–environment relationships and spatial predictions of species richness.
Experimental determination of bending behavior of multilayered and multidirectionally-stitched E-Glass fabric structures for composites

The aim of this study was to experimentally determine the bending behavior of developed multilayered multistitched E-Glass preform structures. For this reason, a bending rigidity test instrument based on the cantilever test principle was used. A bending rigidity test was conducted on all developed multilayered multistitched E-Glass preform structures. Yarn linear density and fabric density influenced the bending rigidity of single layer E-Glass fabric. The single layer fabric's bending rigidity depended on the off-axis angle orientations in the fabric plane. On the other hand, the bending rigidity of the multilayered unstitched E-Glass fabric structure depended on the number of fabric layers. The bending rigidities of the multilayered four directional hand and machine stitched E-Glass preform structures were high compared with one and two directional hand and machine stitched E-Glass preform structures. The bending rigidities of all heavy (6 step/cm) machine stitched E-Glass preform structures were high compared with light (2 step/cm) machine and hand (1 step/cm) stitched E-Glass preform structures. In addition, the bending rigidities of all developed multilayered hand and machine stitched E-Glass preform structures were higher than those of unstitched preform structures due to stitching. In addition, the multilayered multistitched preform structures showed a low order of bending curvatures compared with the multilayered unstitched preform structures. The results indicated that the number of stitching directions and stitching steps substantially affected the bending rigidity of the developed preform structures. Stitching yarn type was also a parameter for the bending behaviorof the multistitched preform structures. It was considered that the unstitched fabric structure could be easily formed whereas the directional stitched E-Glass preform structure became stiff and could not be easily formed.