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The purpose of this paper is to assess the application of graph coloring and domination to solve the airline-scheduling problem. Graph coloring and domination in graphs have plenty of applications in computer, communication, biological, social, air traffic flow network and airline scheduling.

The process of merging the concept of graph node coloring and domination is called the dominator coloring or the χ_d coloring of a graph, which is defined as a proper coloring of nodes in which each node of the graph dominates all nodes of at least one-color class.

The smallest number of colors used in dominator coloring of a graph is called the dominator coloring number of the graph. The dominator coloring of line graph, central graph, middle graph and total graph of some generalized Petersen graph P_(n ,1) is obtained and the relation between them is established.

The dominator coloring number of certain graph is obtained and the association between the dominator coloring number and domination number of it is established in this paper.

The purpose of this paper is to determine the optimum level of geometrical parameters such as helix angle, nose radius, rake angle and machining parameters such as cutting speed, feed rate and depth of cut to arrive minimum surface roughness and tool wear during end milling of Al 356/SiC metal matrix composites (MMCs) using high speed steel end mill cutter.

L27 Taguchi orthogonal design with six factors and three levels is employed for conducting experiments. Analysis of variance (ANOVA) is carried out using Minitab16 software to find the influence of each input parameter on output performance measure. Grey-fuzzy logic multi optimisation algorithm is used to find the optimum level of the input parameters for minimum surface roughness and tool wear simultaneously.

It is found that optimal combination of helix angle 40°, nose radius 0.8 mm, rake angle 12°, cutting speed 90 m/min, feed rate 0.04 mm/rev and depth of cut 1.5 mm have generated minimum surface roughness of 0.4063 µm and tool wear of 0.0375 mm. From ANOVA analysis, it is found that cutting speed influence is more on output performance followed by helix angle and rake angle compared with other machining and geometrical parameters.

The influence of tool geometry during end milling of MMC using Grey-fuzzy logic algorithm has not been explored previously.

The purpose of this paper is to present the results of some corrosion inhibition studies of brass in 3N HNO3 by gemini surfactants.

Gemini surfactants namely: N‐trimethyl butane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (BEAB), N‐hexane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (HEAB), N‐dodecane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (DDEAB) and N‐hexadecane‐diyl‐1,2‐ethane‐bis‐ammonium bromide (HDEAB) were synthesized in the laboratory and their influence has been investigated for controlling the dissolution of brass in 3N HNO3. Weight loss, potentiodynamic polarization and electrochemical impedance have been employed for the study. Weight loss experiments were performed as per standard method (ASTM, 1987). Potentiodynamic polarization studies were carried out using EG&G PARC potentiostat/galvanostat (model 173), universal programmer (model 175) and X‐Y recorder (model RE 0089) and impedance measurements were carried out with an EG&G PAR (model 5301 A) lock‐in‐amplifier, using an IBM computer.

The inhibition efficiency for all the gemini surfactants increases with increase in concentrations. The maximum inhibition efficiency of each inhibitor was achieved at 250 ppm concentration. The inhibition efficiency of all the inhibitors decreases on increasing the temperature from 30 to 50°C. The results of potentiodynamic polarization studies revealed that all the compounds were mixed type inhibitors and inhibit the corrosion of brass by blocking the active sites of the metal. The adsorption of the compounds on brass surface in 3N HNO3 has been found to obey the Langmuir adsorption isotherm.

The paper provides information regarding corrosion inhibition of brass in 3N HNO3, the mechanism of the inhibition on the basis of molecular structures of the inhibitors, activation energy and free energy of adsorption.

Copper and its alloys are widely used in industries because of their good resistance to corrosion and are often used in cooling water systems. Brass has been widely used for shipboard condensers, power plant condensers and petrochemical heat exchangers. Brass is susceptible to the corrosion process known as dezincification by means of which brass looses its valuable physical and mechanical properties leading to failure of structure. The aim of this investigation was to control the dezincification of brass in 3 per cent NaCl solution using benzotriazole (BTA) derivatives.

BTA derivatives namely 1‐hydroxymethylbenzotriazole (HBTA) and N,N‐dibenzotriazol‐l‐ylmethylamine(ABTA) were synthesised and their inhibition behaviour on brass in 3 per cent NaCl solution was investigated by the weight‐loss method, potentiodynamic polarisation, electrochemical impedance and solution analysis techniques. The morphology of the brass after corrosion in the presence and absence of the BTA derivatives was examined using scanning electron microscopy (SEM).

Potentiodynamic polarisation studies showed that the BTA derivatives investigated were mixed type inhibitors, inhibiting the corrosion of brass by blocking the active sites of the brass surface. Changes in the impedance parameters (charge transfer resistance and double layer capacitance) were related to the adsorption of BTA derivatives on the brass surface, leading to the formation of a protective film. Solution analysis revealed that the BTA derivatives excellently controlled the corrosion of brass. SEM micrographs showed the formation of compact surface film on the brass surface in the presence of inhibitors, thereby providing better corrosion inhibition.

Contributes to research on corrosion protection for copper and its alloys.

This study aims to provide a secured data aggregation with reduced energy consumption in WSN. Data aggregation is the process of reducing communication overhead in wireless sensor networks (WSNs). Presently, securing data aggregation is an important research issue in WSNs due to two facts: sensor nodes deployed in the sensitive and open environment are easily targeted by adversaries, and the leakage of aggregated data causes damage in the networks, and these data cannot be retrieved in a short span of time. Most of the traditional cryptographic algorithms provide security for data aggregation, but they do not reduce energy consumption.

Nowadays, the homomorphic cryptosystem is used widely to provide security with low energy consumption, as the aggregation is performed on the ciphertext without decryption at the cluster head. In the present paper, the Paillier additive homomorphic cryptosystem and Boneh et al.’s aggregate signature method are used to encrypt and to verify aggregate data at the base station.

The combination of the two algorithms reduces computation time and energy consumption when compared with the state-of-the-art techniques.

The secured data aggregation is useful in health-related applications, military applications, etc.

The new combination of encryption and signature methods provides confidentiality and integrity. In addition, it consumes less computation time and energy consumption than existing methods.

This paper aims to deal with the influence of cutting parameters on drill thrust force, delamination and surface roughness in the drilling of laminated jute/carbon hybrid composites.

The hybrid composites were fabricated with four layers of fabrics, which are arranged in different sequences using the hand-layup technique. Drilling experiments involved drilling of 6 mm diameter holes on the prepared composite plates using high-speed steel and solid carbide drill materials. Analysis of variance was used to find the influence, percentage contribution and significance of drilling parameters on drilling-induced damages. Scanning electron microscopy analysis was also conducted to understand the fracture behavior and surface morphology of the drilled holes.

The experimental study reveals that the most significant effect was the feed rate influenced the drill thrust force and the drill speed influenced both delamination factor and surface roughness of hybrid fiber-reinforced composites. From observations, the suggested combination for drilling jute/carbon hybrid composites is carbide drill, spindle speed of 1,750 rpm and feed of 0.03 mm/rev.

The new lightweight and low-cost hybrid composites were developed by hybridizing jute with carbon fabrics in the epoxy matrix with interplay arrangements. The influence of cutting speed and feed rate on delamination damage and surface roughness in the drilling of hybrid composites have been experimentally evaluated.

Computed tomography (CT) scan can provide valuable information in the diagnosis of lung diseases. To detect the location of the cancerous lung nodules, this work uses novel deep learning methods. The majority of the early investigations used CT, magnetic resonance and mammography imaging. Using appropriate procedures, the professional doctor in this sector analyses these images to discover and diagnose the various degrees of lung cancer. All of the methods used to discover and detect cancer illnesses are time-consuming, expensive and stressful for the patients. To address all of these issues, appropriate deep learning approaches for analyzing these medical images, which included CT scan images, were utilized.

Radiologists currently employ chest CT scans to detect lung cancer at an early stage. In certain situations, radiologists' perception plays a critical role in identifying lung melanoma which is incorrectly detected. Deep learning is a new, capable and influential approach for predicting medical images. In this paper, the authors employed deep transfer learning algorithms for intelligent classification of lung nodules. Convolutional neural networks (VGG16, VGG19, MobileNet and DenseNet169) are used to constrain the input and output layers of a chest CT scan image dataset.

The collection includes normal chest CT scan pictures as well as images from two kinds of lung cancer, squamous and adenocarcinoma impacted chest CT scan images. According to the confusion matrix results, the VGG16 transfer learning technique has the highest accuracy in lung cancer classification with 91.28% accuracy, followed by VGG19 with 89.39%, MobileNet with 85.60% and DenseNet169 with 83.71% accuracy, which is analyzed using Google Collaborator.

The proposed approach using VGG16 maximizes the classification accuracy when compared to VGG19, MobileNet and DenseNet169. The results are validated by computing the confusion matrix for each network type.

The purpose of this paper is to determine how the soft competencies of an information technology (IT) project manager, specifically optimism and stress, can affect project success.

The research was exploratory. Experienced IT project managers were requested to relate a “structured” story regarding a significant, personal experience relating to optimism or stress and how this affected the project outcome. In total, eight stories were captured on the optimism theme and five on stress. Themes from these stories were identified.

Qualitative analysis of the stories identified several project managers' optimism themes that strongly influenced IT project success. In addition, it was concluded that IT project success was both positively and negatively influenced by stress. To improve their chances of project success, it was concluded that IT project managers should have a positive but realistic degree of optimism based on a well‐accepted project plan. Whilst the project team should expect and embrace stress during the project, this should be carefully managed.

Six important project management practical activities were deduced from the analysis which could assist project managers and their teams to better handle optimism and stress. These activities, when applied effectively, could lead to improved project outcomes.

The article examines Sheikh Ahmad Khatib Al-Minangkabauwi's initial concept of paper money, which in the early 20th century wrote Risala Raf'u Al-Iltibas.

This paper uses a qualitative approach based on the critical extraction analysis that can reveal a set of concepts related to the thoughts of Sheikh Ahmad Khatib Al-Minangkabauwi on paper money.

Through an attentive reading of Sheikh Ahmad Khatib Al-Minangkabawi, the authors can formulate several significant results: First, Ahmad Khatib Al-Minangkabawi applies two methods in studying critically on paper money, namely, the comparative law method and qiyas. Second, Ahmad Khatib believes that paper money has similarities with dinars and dirhams, namely its nominal value function. It is just that the existence of these values is different. Briefly, there are set law consequences for those who used paper money in economic activities, i.e. payment of zakāt on paper money applies when used as business capital.

Sheikh Ahmad Khatib Al-Minangkabawi's work related to paper money is written heavily from the perspective of fiqh. Briefly, it is challenging to describe legal reasoning from work. As a result, articles are also thicker with fiqh analysis.

Sheikh Ahmad Khatib Al-Minangkabawi's view regarding paper money becomes the foundation for the theory of the value of money in Islam. However, it is rarely disclosed. In this regard, this paper can serve as the foundation of the value for money offered by scholars from Indonesia in the early 20th century.

Money is not a commodity. Still, it must be positioned as capital to be productive. It finally becomes why trade is compelling and becomes the most practical reason for paying out zakāt.

It is not easy finding out articles that attempt to reveal the concept of classical ulemas or clerics from Indonesia relating to paper money. This article manages to identify that, and at the same time, becomes a novelty.

The purpose of this paper to analyze the effect of Soret with heat and mass transfer on an unsteady two-dimensional Magnetohydrodynamics flow through a porous medium under the influence of the uniform transverse magnetic field in a rotating parallel plate is considered.

A mathematical model was developed using the slip conditions under unsteady state situations. Analytical expressions for the velocity, temperature and concentration profiles, wall shear stress, rates of heat and mass transfer and volumetric flow rate were obtained and computationally discussed with respect to the non-dimensional parameters. Further, the velocity reduces with increasing Hartmann number M and increases with Grashof number Gr and permeability parameter K.

It is observed that temperature reduces with an increase in Prandtl number Pr and ω. It is noted that the thermal radiation increases with increase in Soret number Sr, Schmidt number Sc, Prandtl number pr and ω.

Concentration decreases with an increase in radiation parameter R and chemical reaction parameter Kc.