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Before using concrete for a particular purpose, its strength must be determined because its physical properties vary depending on the type of supplementary cementitious material (SCMs). Initially, researchers anticipated it with statistical processes; more recently, they started implementing deep learning (DL) and machine learning (ML) models. This research employed ensemble machine learning (EML) approaches to predict the compressive strength (CS) of concrete developed for ground-granulated blast furnace slag (GGBFS) along with Alccofine 1203 (AF). Ensemble regressions of Random Forest Regression (RFR) and AdaBoost Regression (ABR) were considered for model prediction using the Jupyter Notebook. The models were created based on the outcome of the compressive strength under the 90 experimental conditions. Moreover, a comparative study was performed between the RFR and ABR to benchmark the proposed model against a given combination of features and CS. The experimental conditions were optimized using a genetic algorithm (GA) after the model was created by ANN. With the two EML algorithms, the smallest errors, along with the largest coefficient of determination, were observed in the RFR algorithm. It was recognized that the optimized value of CS is 48.606 MPa, and their optimized process elements such as cement, alccofine, GGBS, water, and days were 261.506 kg/m3, 0.055 kg/m3, 52.468 kg/m3, 141.007 L, and 27.999 days, respectively.

Performance based analysis is conducted on a structure to know the performance of building under severe earthquake loads with limited and well-distributed damage. To do this analysis a non-linear static analysis called pushover analysis had conducted on the structure. In this paper, an RC building with both 5 storey and 10 storey is designed for both gravity loads and earthquake resistant loads using SAP2000 software. Analysis is done in both X and Y direction to get a damage curve (pushover curve). By studying the damage curve, the results that obtained are earthquake resistant designed building had more strength when compared to gravity load designed building and it is better to consider earthquake in building design , because gravity loads alone cannot give the adequate results.

Non-linear static analysis or pushover analysis is now-a –days generally preferred by many researchers to analyse the non-linear behaviour of the structure. Present study includes the effect of joint rigidity on the behaviour of the structure. A building is modeled with 5 and 10 story and designed for gravity and earthquake resistant loads by considering joint rigidity factor as 0 and 1. The analysis is done in both X and Y directions by using pushover analysis in SAP2000 software. Comparison is made between then capacity curves obtained from designed models of rigidity and non-rigidity models. From the results it is concluded that structure designed using joint rigidity has more strength when compared non-rigid joints.

Aeroengine gas turbine components operate under complex loading environments. Turbine disc is one such component which experiences stresses at high temperature and accumulates life critical cyclic damage in the material during usage. This accumulation of cyclic damage results into significant deterioration in material strength which in turn may initiate the failure in these rotating components. This necessitates the need to develop an advanced lifing approach for fatigue life assessment of turbine disc. As there are no available standards for damage mechanics application, an attempt has been made in the present study to develop a methodology for application of damage mechanics approach to model high temperature fatigue damage evolution in a turbine disc Superalloy. High temperature (650 °C) stress-controlled fatigue tests on turbine disc alloy have been performed to evaluate parameters for damage mechanics based models. Using this approach, damage evolution has been simulated at specimen level. A good correlation has been observed in the damage mechanics based model's predicted damage and experimentally determined values. [ABSTRACT FROM AUTHOR]

A simple, flexible and very low cost hardware plus software framework for developing computer-interfaced science experiments is presented. It can be used for developing computer-interfaced science experiments without getting into the details of electronics or computer programming. For developing experiments this is a middle path between "push-button systems" and the "develop-from-scratch" approach. Emphasis is on leveraging the power of personal computers for experiment control, data acquisition and the mathematical analysis of data. The language "Python" is chosen for data acquisition and analysis. This article explains the architecture of Phoenix (Physics with Home-made Equipment and Innovative Experiments) along with some sample experiments. The hardware design is open and the project is totally based on free software. (Contains 6 figures.)

Modern power systems need the expansion of EHV and UHV power Transmission networks due to the exponential rise in power demand. The Ferranti effect needs the attention of researchers on the dynamic variation of loads in interconnected power systems. This article focuses on the development of closed-loop control circuitry for both Static Synchronous Compensator (STATCOM) and Static Var Compensator (SVC). The developed transmission system Simulink model has been simulated and Ferranti Effect is observed for both no-load and lightly loaded conditions. The closed-loop control circuits along with power circuits of STATCOM and SVC have been developed and simulated and the results show the significant suppression of the Ferranti effect by both of the shunt devices. [ABSTRACT FROM AUTHOR]

Stone columns are the most suitable and economical ground improvement technique for soft soils. Stone columns accelerate the consolidation process, thereby increase the stiffness of the soil. This increase may not be sufficient because of the less lateral confinement, which leads to excessive bulging. The strength of the composite soil can also be increased further by encasing the column with geotextile. In this paper, model tests were conducted on end-bearing stone columns with geotextile encasement and compared with the unreinforced (plain) stone columns. The stone columns were prepared by placing the silica-manganese slag, sand and were reinforced with geotextile with different encasement lengths of D, 2D, 3D, and 4D (D is the stone column diameter; i.e., 5 cm). The tests demonstrated that the engineering behavior of the soil was improved by introducing the silica-manganese slag (when compared with conventional stone columns) and also with encasement. Bulging can also be reduced by providing encasement beyond the zone of bulging. [ABSTRACT FROM AUTHOR]

Among all the techniques available for ground improvement, stone columns are the most preferred elements used for supporting a wide variety of flexible structures such as road, railway embankments, and oil storage tanks. In this study, several laboratory tests have been conducted to improve the soft marine clay with end bearing stone columns by using Silica-Manganese slag as stone column material. Further, these stone columns were reinforced with circular geotextile discs by placing them laterally within the column. The improvement in load carrying capacity was studied and compared to the clay bed and unreinforced i.e. plain stone column. Circular geotextile discs of two different spacings (D and D/2, where "D" is the diameter of the stone column) with varied reinforcement depths, such as D, 2D, 3D and 4D, were tried. It was found that the soil reinforced with a spacing of D/2 to the embedment length of 3D shows better performance than a spacing of D. It was also observed that the bulging diameter was reduced by incorporation of the geotextile reinforcement and found below the reinforcement. [ABSTRACT FROM AUTHOR]

An efficient protocol has been developed for the preparation of a library of benzoxazole, benzimidazole, and benzothiazole derivatives from reactions of acyl chlorides with o-substituted aminoaromatics in the presence of catalytic amount of silica-supported sodium hydrogen sulphate under solvent-free conditions. Simple workup procedure, high yield, easy availability, reusability, and use of ecofriendly catalyst are some of the striking features of the present protocol. [ABSTRACT FROM AUTHOR]

PbO-As2O3 glasses mixed with different concentrations of TiO2 (ranging from 0 to 1.0 mol%) were crystallized. The samples were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy (EDS) techniques. Studies were extended to optical absorption, IR, ESR, luminescence and magnetic susceptibility on these samples. The X-ray diffraction studies reveal the presence of Pb3O4, Ti(As2O7), Pb(As2O6), Pb3(AsO4)2 PbTi3O7 and Ti2O3 crystal phases. The optical absorption studies together with ESR and magnetic susceptibility measurements indicated that the titanium ions exist in both Ti3+ and Ti4+ states in all the samples and there is an increase in titanium ions in the trivalent state with increasing concentration of nucleating agent TiO2. The quantitative analysis of these results indicated that there is a growing degree of disorder in the glass network with increasing concentration of the crystallizing agent. The luminescence studies indicated that the samples crystallized with low concentrations of TiO2 show high luminescence efficiency in the visible region. [ABSTRACT FROM AUTHOR]

A series of intermolecular hydrogen bonding complexes, 2,2′-bipyridine: p- n-alkoxybenzoic acids (BP : nABA) was isolated from liquid crystalline p-n-alkoxybenzoic acids (nABA) (where n represents alkoxy carbon numbers, 3 to 10 and 12) and a non-mesogen, 2,2′-bipyridine (BP). The thermal and phase behaviour of these complexes was studied by thermal microscopy and differential scanning calorimetry (DSC). These studies revealed the induction of tilted smectic F and crystal G phases. The structural elucidation pertaining to the formation of intermolecular hydrogen bonding was carried out by a detailed IR spectral investigation. Comparative crystallization kinectic studies using DSC, performed on two representative compounds, showed different forms of the crystallization process. The magnitudes of the Avrami exponent n suggests two different mechanisms operate for individual members leading to sporadic three-dimensional growth. Nevertheless, an overall unique mechanism is predicted to operate at each crystallization temperature investigated, while the Avrami constant b shows a temperature dependence suggesting a strong influence of alkoxy terminal groups on the rates of nucleation. [ABSTRACT FROM AUTHOR]

Tetrahydropyranyl (THP) ethers have been efficiently and simply deprotected by using Silica supported sodium hydrogen sulphate (NaHSO4-SiO2) in methanol at room temperature to regenerate the parent alcohols in high yields. [ABSTRACT FROM AUTHOR]