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To develop a new corrosion inhibitor formulation for carbon steel in low chloride environments.

Corrosion inhibition efficiencies were evaluated by the weight loss method and by impedance measurement studies. The nature of the inhibition process was evaluated using potentiostatic polarization studies. The nature of the protective film was investigated using X‐ray diffraction, X‐ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The concept of synergistic effect was used in the development of the new synergistic inhibitor formulation.

A new corrosion inhibitor formulation, containing tertiary butyl phosphonate (TBP), zinc ions and citrate, has been developed to control the corrosion of carbon steel in low chloride environments. This inhibitor formulation was found to offer a maximum inhibition efficiency of 96 per cent in a neutral pH test environment. It was interesting to observe that the binary system, consisting of higher concentrations of the TBP and zinc ions, offered only 79 per cent inhibition efficiency. The ternary system, consisting of relatively lower concentrations of the phosphonate, zinc ions and citrate offered a higher (96 per cent) efficiency. This ternary inhibitor system also was found to be efficient in acidic as well as basic environments in the pH range 5‐8. The inhibitor combination was determined to function as a “mixed”‐type inhibitor, though being predominantly cathodic. A plausible explanation of the mechanism of corrosion inhibition is proposed.

The ternary inhibitor formulations based on phosphonate, zinc ions and another environmentally friendly synergists like citrate will be quite useful for corrosion inhibition of carbon steel in cooling water systems as they contain relatively less concentrations of phosphonate and zinc ions.

The research paper presents the results of a new synergistic inhibitor formulation and also discusses the mechanistic aspects of corrosion inhibition.

The paper aims to throw light on the interactions taking place between the different chemical compositions at various temperatures. P-methylacetophenone is a polar dissolvable, which is positively related by dipole–dipole co-operations and is exceptionally compelling a direct result of the shortfall of any critical primary impacts because of the absence of hydrogen bonds; hence, it might work an enormous dipole moment (μ = 3.62 D). Alcohols additionally assume a significant part in industries and research facilities as reagents and pull in incredible consideration as helpful solvents in the green innovation. They are utilized as pressure-driven liquids in drugs, beauty care products, aromas, paints removers, flavors, dye stuffs and as a germ-free specialist.

Mixtures were prepared by mass in airtight ground stopper bottles. The mass measurements were performed on a digital electronic balance (Mettler Toledo AB135, Switzerland) with an uncertainty of ±0.0001 g. The uncertainty in mole fraction was thus estimated to be less than ±0.0001. The densities of pure liquids and their mixtures were determined using a density meter (DDH-2911, Rudolph Research Analytical). The instrument was calibrated frequently using deionized doubly distilled water and dry air. The estimated uncertainty associated with density measurements is ±0.0003 g.cm⁻³. Viscosities of the pure liquids and their mixtures were determined by using Ostwald’s viscometer. The viscometer was calibrated at each required temperature using doubly distilled water. The viscometer was cleaned, dried and is filled with the sample liquid in a bulb having capacity of 10 ml. The viscometer was then kept in a transparent walled water bath with a thermal stability of ±0.01K for about 20 min to obtain thermal equilibrium. An electronic digital stop watch with an uncertainty of ±0.01 s was used for the flow time measurements for each sample at least four readings were taken and then the average of these was taken.

Negative values of excess molar volume, excess isentropic compressibility and positive values of deviation in viscosity including excess Gibbs energy of activation of viscous flow at different temperatures (303.15, 308.15 and 313.15 K) may be attribution to the specific intermolecular interactions through the hetero-association interaction between the components of the mixtures, resulting in the formation of associated complexes through hydrogen bond interactions.

The excess molar volume (V^E) values were analyzed with the Prigogine–Flory–Patterson theory, which demonstrated that the free volume contribution is the one of the factors influencing negative values of excess molar quantities. The Jouyban–Acree model was used to correlate the experimental values of density, speed of sound and viscosity.

The purpose of this paper is to improve energy efficiency and further reduction of side lobe level the algorithm proposed is firework algorithm. In this paper, roused by the eminent swarm conduct of firecrackers, a novel multitude insight calculation called fireworks algorithm (FA) is proposed for work enhancement. The FA is introduced and actualized by mimicking the blast procedure of firecrackers. In the FA, two blast (search) forms are utilized and systems for keeping decent variety of sparkles are likewise all around planned. To approve the presentation of the proposed FA, correlation tests were led on nine benchmark test capacities among the FA, the standard PSO (SPSO) and the clonal PSO (CPSO).

The antenna arrays are used to improve the capacity and spectral efficiency of wireless communication system. The latest communication systems use the antenna array technology to improve the spectral efficiency, fill rate and the energy efficiency of the communication system can be enhanced. One of the most important properties of antenna array is beam pattern. A directional main lobe with low side lobe level (SLL) of the beam pattern will reduce the interference and enhance the quality of communication. The classical methods for reducing the side lobe level are differential evolution algorithm and PSO algorithm. In this paper, roused by the eminent swarm conduct of firecrackers, a novel multitude insight calculation called fireworks algorithm (FA) is proposed for work enhancement. The FA is introduced and actualized by mimicking the blast procedure of firecrackers. In the FA, two blast (search) forms are utilized and systems for keeping decent variety of sparkles are likewise all around planned. To approve the presentation of the proposed FA, correlation tests were led on nine benchmark test capacities among the FA, the standard PSO (SPSO) and the clonal PSO (CPSO). It is demonstrated that the FA plainly beats the SPSO and the CPSO in both enhancement exactness and combination speed. The results convey that the side lobe level is reduced to −34.78dB and fill rate is increased to 78.53.

Samples including 16-element LAAs are conducted to verify the optimization performances of the SLL reductions. Simulation results show that the SLLs can be effectively reduced by FA. Moreover, compared with other benchmark algorithms, fireworks has a better performance in terms of the accuracy, the convergence rate and the stability.

With the use of algorithms radiation is prone to noise one way or other. Even with any optimizations we cannot expect radiation to be ideal. Power dissipation or electro magnetic interference is bound to happen, but the use of optimization algorithms tries to reduce them to the extent that is possible.

16-element linear antenna array is available with latest versions of Matlab.

The latest technologies and emerging developments in the field of communication and with exponential growth in users the capacity of communication system has bottlenecks. The antenna arrays are used to improve the capacity and spectral efficiency of wireless communication system. The latest communication systems use the antenna array technology which is to improve the spectral efficiency, fill rate and the energy efficiency of the communication system can be enhanced.

By using FA, the fill rate is increased to 78.53 and the side lobe level is reduced to 35dB, when compared with the bench mark algorithms.

This study aims to optionally-piloted aircraft is useful for in-flight tests of new automatic controller’s concepts. The safety of this kind of experiment is an issue addressed in this paper. The prediction of possible safety-influencing factors makes it possible to assess the pilot’s ability to effectively prevent safety risks.

The analysis in this research paper focusses on two cases of monitoring; similar control standards for both pilot in command and the monitoring pilot or technical systems in one of these tasks and dissimilar control standard when monitoring pilot is not familiar with a control manner of the pilot in command or of the automatic control system. The increased workload is expected in the last case as the result of additional activities determined theoretically in the presented analysis. Details of the possible threats are obtained by simulation tests with various factors influencing the safety of landing. In addition to determining threats, the analysis includes the possibility of in time threat detection and preserving action.

The results show that the safety pilot has a different task than the pilot in command and needs to be familiar with the general principles of automatic controller operations and the particular algorithm being tested. Although commonly used landing procedure is relatively error-tolerant, new landing procedures for use in some specific conditions need more precise control and additional safety pilot preparation. Additional information presented to both the pilot in command and the safety pilot may increase mode and state awareness and reduce reaction time in an emergency condition.

In-flight tests of non-standard control algorithms there is a need to include additional preparation of the equipment and safety pilot. The research in this paper illustrates how to determine threats and safety-critical moments during the experimental flight can be observed. The danger is mitigated by the safety pilot, if familiar with both proper and improper operations of the controller and how the pilot in command should detect and predict danger caused by the tested control system.

The presented method of analysis combines the human factor with various technical aspects. The results obtained illustrate the real tasks of the person supervising the operation of the automatic control system and the role of a human as a safety pilot.

Lightweight insulators are of major importance for the industry, in particular for thermal insulation in buildings. The purpose of this paper is to present a low-cost method to obtain aerogels with high insulating properties.

Silica aerogel structures have been obtained by a low-cost sol-gel synthesis method. Surface modification, using dimethyldichlorosilane and trimethylchlorosilane, has been applied in order to get different thermal and optical properties.

The samples show very promising thermal properties as tested through an infrared camera observation. A 5-mm-thick piece of aerogel is able to withstand the temperature of a brazing flame and reduce the heat by at least 150 degrees on its opposite side. The samples have a vitreous like structure as observed by SEM, some surface cracking is observed but they stay within acceptable limits.

A very good thermal insulator is obtained with a very simple and low-cost method. The bulkiness of the supercritical drying is eliminated and the obtained structure has good properties.

Neural network (NN)-based deep learning (DL) approach is considered for sentiment analysis (SA) by incorporating convolutional neural network (CNN), bi-directional long short-term memory (Bi-LSTM) and attention methods. Unlike the conventional supervised machine learning natural language processing algorithms, the authors have used unsupervised deep learning algorithms.

The method presented for sentiment analysis is designed using CNN, Bi-LSTM and the attention mechanism. Word2vec word embedding is used for natural language processing (NLP). The discussed approach is designed for sentence-level SA which consists of one embedding layer, two convolutional layers with max-pooling, one LSTM layer and two fully connected (FC) layers. Overall the system training time is 30 min.

The method performance is analyzed using metrics like precision, recall, F1 score, and accuracy. CNN is helped to reduce the complexity and Bi-LSTM is helped to process the long sequence input text.

The attention mechanism is adopted to decide the significance of every hidden state and give a weighted sum of all the features fed as input.

Using dynamic capabilities theory, this paper aims to posit logistics capabilities (namely information, demand, supply, cooperation and coordination) when integrated at the supply chain level gives rise to supply chain resilience. The current investigation explores further on the inter-relationship among dominant logistics capabilities and integrated logistics capabilities.

To test the proposed hypotheses, data were gathered from 339 supply chain professionals and were evaluated through structural equation modeling. The measures were pretested through exploratory factor analysis and confirmatory factor analysis and then measures were deployed for final testing.

Findings suggest that logistics capabilities do exert a strong influence on supply chain resilience through effective logistics integration. Further, these logistics capabilities do share certain inter-relationships among themselves. Supply chain resilience does have positive performance implications. The authors also tested for moderation of cooperation and coordination and proposed an alternate model which found support in post hoc testing.

The study holds immense value for practitioners and managers, as they undersigned that logistics capabilities need to be integrated at the supply chain level for developing overall supply chain resilience. Further, it underscored how the inter-relationship among the individual logistics capabilities varies in the development of supply chain resilience.

The equation of motion of a beam on multiple supports, subject to prescribed time‐dependent conservative axial loads, is formulated based on Hamilton’s principle and the assumed mode method. The effects of sinusoidal perturbations in respect of the axial loads are then examined using Bolotin’s method. The respective regions of instability are determined by converting the resulting equations of boundary frequencies into the standard form of a generalized eigenvalue problem. Instability regions are presented for various combinations of support configuration, average value and amplitude of the sinusoidal perturbations of the axial loads.

Tourism supply chains (SCs) are recently gaining importance and there is a dire need for empirical testing and theory development in allied areas. The current investigation aims to explore the importance of management learning, relationship development, shared vision, inter-firm integration and technology perception as essential management capabilities required for the development of dynamic capability of tourism SC agility. Furthermore, the study explores the agile influence on competitive advantage.

The study collected perceptual responses from 233 active participants and respondents in the tourism sector. The collected data were analyzed for the validity of the proposed relationships through partial least squares.

Findings suggest relationship development, shared vision, inter-firm integration and technology perception as significant enablers. Furthermore, tourism SC agility was found to enhance competitive advantage.

The study further advances theory development and empirical testing through extending the concept of agility to tourism SCs and examining its enablers. Furthermore, the study developed measured for the utilized enablers of tourism SC agility through appropriate development in tourism contexts.

Microstrip patch antenna is generally used for several communication purposes particularly in the military and civilian applications. Even though several techniques have been made numerous achievements in several fields, some systems require additional improvements to meet few challenges. Yet, they require application-specific improvement for optimally designing microstrip patch antenna. The paper aims to discuss these issues.

This paper intends to adopt an advanced meta-heuristic search algorithm called as grey wolf optimization (GWO), which is said to be inspired by the hunting behaviour of grey wolves, for the design of patch antenna parameters. The searching for the optimal design of the antenna is paced up using the opposition-based solution search. Moreover, the proposed model derives a nonlinear objective model to aid the design of the solution space of antenna parameters. After executing the simulation model, this paper compares the performance of the proposed GWO-based microstrip patch antenna with several conventional models.

The gain of the proposed model is 27.05 per cent better than WOAD, 2.07 per cent better than AAD, 15.80 per cent better than GAD, 17.49 per cent better than PSAD and 3.77 per cent better than GWAD model. Thus, it has proved that the proposed antenna model has attained high gain, leads to cause superior performance.

This paper presents a technique for designing the microstrip patch antenna, using the proposed GWO algorithm. This is the first work utilizes GWO-based optimization for microstrip patch antenna.