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The purpose of this paper is to study the effect of injection and suction on velocity profile, skin friction and pressure distribution of a Casson fluid flow between two parallel infinite rectangular plates approaching or receding from each other with suction or injection at the porous plates.

The governing Navier–Stokes equations are reduced to the fourth-order non-linear ordinary differential equation through the similarity transformations. The approximated analytic solution based on the Homotopy perturbation method is given and also compared with the classical finite difference method.

From this study, the authors observed that the skin friction is less in non-Newtonian fluids compared to Newtonian fluids. The use of non-Newtonian fluids reduces the pressure in all the cases compared to Newtonian and hence load-carrying capacity will be more. As γ value increases velocity, skin friction and pressure decreases. When γ is fixed, it is observed that skin friction and pressure is minimum for A=0.5 and maximum when A=−0.5. The result of this study also shows that the effect of suction on the velocity profiles, pressure and skin friction is opposite to the effect of injection.

The present work analyzes the characteristic of non-Newtonian fluid having practical and industrial applications.

Stainless steel is one of the most important elements in structural design and application, and due to its excellent properties, it is widely used in industries for conventional structural engineering applications, such as thermal power plants, nuclear power plants, civil constructions, etc. (Mishra et al., 2014). A traditional tensile testing machine cannot determine the transversal stress–strain curves (Olden, 2002, 2013).

In the present study, identical mild steel specimen parts are welded at different intervals and then subjected to tensile loading. Welding is carried along the length of the specimen. Induced stresses are determined at the welded intervals and the stress–strain curve is obtained.

By considering the temperature of the weld at the interface, thermal stresses are determined. Brinell hardness number is determined at the interface and the base metal. Also, the change in the hardness at the heat-affected zone (HAZ) is found. Validation is carried out by comparing the results with the original stress–strain curve.

In the HAZ, there is a drop in the hardness number, which means that there is a change in the material property due to welding. The thermal stresses which develop at the interface can also play a very important role for property change. Results show that the stress developed due to the rise in temperature is lesser than that of normal stresses.

The purpose of this paper is to present the design and development of transfer seat system which aids the disabled drivers to get in and out of the car without outside help thereby reducing physical effort. The design of the model is carried out taking into account the vehicle specification and the weight of the person. After careful measurement and analysis, the required seat system parameters were estimated. The three movements associated with the system are satisfied with motors controlled by switches. The design calculations and the tests carried out are validated using the ANSYS finite element software.

The whole process begins with the definition of the problem of eliminating the support of an additional person to help people with disabilities enter and leave a car, making it feasible and economical for the patients. Literature review includes and develops information from different sources. The research gap is identified and a necessary improvement is proposed. Design and analysis involves optimum design and calculation that achieves the efficiency, reliability and comfortable movement of the system. It also involves validation to support stress analysis in the system that is performed using ANSYS. The material supply includes the required materials taking into account factors such as strength, durability and availability. Manufacturing selects appropriate manufacturing techniques taking into account design, materials and space limitation. Operations such as welding, cutting, drilling and grinding are considered. The tests consist of performing a physical test to check the approximate load capacity of the system for a gentle, comfortable and secure comfort. Validation ensures that the results of the test coincide with the existing results of the supporting documentation. This process also involves taking corrective action and re-doing the design process to achieve the desired results.

The results that are plotted suggest that with the increase in downward force, the power required to balance it is greater. Similarly, the speed increases with increasing power. ANSYS analysis can be performed for the support structure and for obtaining deformation. The entire work can be implemented on the actual vehicle, and the time required for the patient to enter and exit could be calculated. The entire transfer system that operates by the engine can be modified, and a hydraulic system can be used to make the movements possible. The section of the rail can also be modified accordingly, and the comparison of the possible results can be carried out with the present system.

The entire system can be improvised by working on the mechanism which reduces the overall operating time without causing discomfort to the user when entering and exiting the car. Furthermore, the safety feature must be considered in the car to prevent the mechanism from altering the seating position of the seat, for which a mooring system can be inserted with a switch to hold it in place and release it. A powerful motor can be integrated into the mechanism to improvise the second movement, which is the deployment of the legs on the ground with the motorized wheels. The set of cast iron rails is used to support more weight without failure.

The main objective is to design a system that allows a disabled person to enter and exit easily without the support or assistance of a second person. The design process had to be modified, and various methods were tried to incorporate this flawless movement onto the chassis of the car. Necessary changes have been made in the case of the material used and of the yarn to obtain the desired movement at the desired speed at the desired time. By performing these three movements, the secondary objective had to be integrated into the system to automate the door to facilitate the entry and exit of the car and to open the door simply by pressing a button. These results were taken into account to make the engine speed changes and the speed at which the chair will descend and move horizontally to ensure a safe design.

The developed transfer seat system can be widely used in healthcare sectors which greatly helps the movement of disabled persons.

The design calculations and tests carried out are validated using the ANSYS®, a finite element software.

The main objectives of this research work were to investigate the effect of production speed on intermingled yarn properties and melange fabric properties with special reference to melange appearance.

Polyester/nylon intermingled yarns were produced using an SSM DP3-C air-intermingling machine using commercial process parameters and Heberlein P212 nozzle. Melange fabric samples were knitted from polyester/nylon intermingled yarns while maintaining the same parameters to avoid knitting variations. The fabric samples were dyed using a sample dyeing machine while maintaining dye recipe and dyeing parameters constant to avoid dyeing variations.

The production speed has significant effect on intermingled yarn and melange fabric properties. When the production speed is increased, mingle points, mingle stability, linear density, strength and the elongation of the intermingled yarns decreases. When the production speed is increased, fabric weight decreases and the melange effect varies from dot-like appearance to line-like appearance.

Only the effect of production speed on intermingled yarn and melange fabric properties is discussed in this paper. Appearance evaluating systems developed in this research are limited to melange fabrics produced using air-intermingled yarns with two colour components.

Results indicate that the intermingled yarns for the application of melange fabrics should be developed with optimum intermingling speeds, and it should not be changed during the production since production speed has significant effect on yarn and fabric parameters. Therefore, melange appearance and fabric weight may vary between fabric lots with different production speeds even though all the other parameters are kept constant. Further, melange appearance evaluation method developed in this research could be used as a guide in developing melange fabrics.

This research introduced a qualitative and a quantitative method to analyse melange fabric appearance. This melange appearance evaluation method can be used as a guide to achieve specific melange effect in the sample development stage. Further, when a melange sample appearance catalogue is developed for all the variables for a particular fabric type using this evaluation method, customer requested appearance can be achieved in minimum sample trials which save time, capacity, money and customer credibility.

This study examines the osteoconductive and healing capabilities of locally implanted synthetic hydroxyapatite (sHAp) derived from eggshells in the central incisor sockets of rats.

Toxicity experiments were conducted in vitro and in vivo, to testify the safety dosage of sHAp. Around 24 mature male Sprague–Dawley (SD) rats had their upper central incisors extracted. The rats were placed into three groups of eight rats each: Group 1: the sockets of extracted central incisors were left unfilled (control), Group 2: filled up with commercially available hydroxyapatite (HAp) and Group 3: implanted with sHAp locally retrieved from eggshells. After extraction, four rats from each group were sacrificed at 2nd and 4th weeks. Maxillary tissue sections were obtained and stained with hematoxylin and eosin (H&E) and Masson’s trichome (MT) staining. Anti-osteocalcin (OCN) and proliferating cell nuclear antigen (PCNA) were used primary antibodies for immunohistochemistry (IHC) special labeling.

The results showed that the locally implanted sHAp was non-toxic and safe in cell lines (human osteoblast and fibroblast) and animals. Histological analysis of H&E, MT and IHC showed that the sockets treated with locally implanted sHAp from eggshells were filled with new bone tissue of comparable thickness to other groups.

This unique technique uses locally implanted eggshell-derived sHAp with osteoconductive characteristics. In an in vivo model, sHAps increased OCN and PCNA expression to improve bone repair.

The advent of robotics and automation technologies was augmenting firm initiatives to attain competitive advantage. From a resource-based view perspective, human-led capabilities were important to operate with technology resource base of an organisation. This was evident for both manufacturing as well as services firms. However, employees as an individual confronted technology anxiety (TA) when they were working with new technologies like robotics and automation technologies. Thus, the purpose of this paper was to examine the factors causing TA.

Given the novelty of this research study context a qualitative exploratory method was designed. For this research study, the data collected was through in-depth interviews conducted through open-ended semi-structured questionnaire. The data was collected from 62 frontline employees who were working with robotics and automation-based technologies in manufacturing firms. The authors applied thematic content analysis on collected data for analysis.

Technology anxieties ranged from fear of complete inability to learn new technologies, failure to learn new technologies properly, incapability to implement the learned skills and job loss to younger technology savvy employees. Finally, there was anxiety over job loss as automation and robotic technologies over the years was expected to erode the employment of human workforce altogether.

The author undertook the research study based upon the TA perspective advocated by Meuter et al. (2003) and Yang and Forney (2013). Furthermore, this research study in the context of robotics and automation-based technologies in the manufacturing sector applied the mental accounting theory (Thaler, 1999) and technology self-efficacy perspective (Huffman et al., 2013).

Managers involved in the implementation of robotics and automation-based technologies were required to address TA of employees. Fear of job loss had to be addressed specially in a country like India. Anxiety regarding the ability to learn to work with robotics and automation technologies also was needed to be addressed by managers through adequate training and time for preparation. The benefits of robotics and automation-based technologies for employees as well as organisations have to be ascertained through open communication between the management and the frontline employees.

To the best of the authors’ knowledge, this was one of the first empirical research studies which deliberated regarding TA in the context of frontline workers working with robotics and automation-based technologies in the manufacturing sector. This research study was based upon a combination of varied perspectives ranging from micro foundations theory, TA, mental accounting theory and technology self-efficacy perspective.

This study investigated the crossover of work–family conflict (WFC) from supervisors to subordinates employed in conventional work settings. The authors hypothesized that the supervisor’s WFC would impact the subordinate’s level of WFC, and the level of crossover would vary with relationship quality or LMX.

The authors surveyed a matched set of 150 supervisors and 193 subordinates from several services organizations who were recruited using a snowballing technique. Data were analysed using hierarchical regression analyses and moderation testing.

Results confirmed a significant direct crossover path. Further, the crossover was found to be lowered in the event of higher LMX quality.

The findings provide significant insights into the conditions under which transmission of WFC takes place by broadening crossover research in the work–family area. Future studies must explore the crossover of work–family enrichment and the role of leadership styles, empathy and perspective taking of subordinates in the crossover.

Supervisors must endeavour to reduce the level of WFC of subordinates by trying to build high-quality LMX by regularly interacting with them and by providing them a supportive climate. Employees in turn must support supervisors in various means, which will help them gaining manager’s trust and support.

Examination of the potential mitigating effect of high-quality LMX in the crossover of WFC in supervisor–subordinate dyads has rarely been investigated in the past.

Purpose of this paper are Real power loss reduction, voltage stability enhancement and minimization of Voltage deviation.

In HLG approach as per Henry gas law sum of gas dissolved in the liquid is directly proportional to the partial pressure on above the liquid. Gas dissolving in the liquid which based on Henry gas law is main concept to formulate the proposed algorithm. Populations are divided into groups and all the groups possess the similar Henry constant value. Exploration and exploitation has been balanced effectively. Ranking and position of the worst agents is done in order to avoid the local optima. Then in this work Mobula alfredi optimization (MAO) algorithm is projected to solve optimal reactive power problem. Foraging actions of Mobula alfredi has been imitated to design the algorithm. String foraging, twister foraging and backward roll foraging are mathematically formulated to solve the problem. In the entire exploration space the Mobula alfredi has been forced to discover new regions by assigning capricious position. Through this approach, exploration competence of the algorithm has been improved. In all iterations, the position of the Mobula alfredi has been updated and replaced with the most excellent solution found so far. Exploration and exploitation capabilities have been maintained sequentially. Then in this work balanced condition algorithm (BCA) is projected to solve optimal reactive power problem. Proposed BCA approach based on the conception in physics- on the subject of the mass; incoming, exit and producing in the control volume. Preliminary population has been created based on the dimensions and number of particles and it initialized capriciously in the exploration space with minimum and maximum concentration. Production control parameter and Production probability utilized to control the exploration and exploitation.

Proposed Henry's Law based -soluble gas optimization (HLG) algorithm, Mobula alfredi optimization (MAO) algorithm and BCA are evaluated in IEEE 30 bus system with L-index (Voltage stability) and also tested in standard IEEE 14, 30, 57, 118, 300 bus test systems without L- index. Real power loss minimization, voltage deviation minimization, and voltage stability index enhancement has been attained.

For the first time Henry's Law based -soluble gas optimization (HLG) algorithm, Mobula alfredi optimization (MAO) algorithm and BCA is projected to solve the power loss reduction problem.

The use of AI for operations management, with its ability to evolve solutions, handle uncertainty and perform optimisation continues to be a major field of research. The growing body of publications over the last two decades means that it can be difficult to keep track of what has been done previously, what has worked, and what really needs to be addressed. Hence, the purpose of this paper is to present a survey of the use of AI in operations management aimed at presenting the key research themes, trends and directions of research.

The paper builds upon our previous survey of this field which was carried out for the ten‐year period 1995‐2004. Like the previous survey, it uses Elsevier's Science Direct database as a source. The framework and methodology adopted for the survey is kept as similar as possible to enable continuity and comparison of trends. Thus, the application categories adopted are: design; scheduling; process planning and control; and quality, maintenance and fault diagnosis. Research on utilising neural networks, case‐based reasoning (CBR), fuzzy logic (FL), knowledge‐Based systems (KBS), data mining, and hybrid AI in the four application areas are identified.

The survey categorises over 1,400 papers, identifying the uses of AI in the four categories of operations management and concludes with an analysis of the trends, gaps and directions for future research. The findings include: the trends for design and scheduling show a dramatic increase in the use of genetic algorithms since 2003 that reflect recognition of their success in these areas; there is a significant decline in research on use of KBS, reflecting their transition into practice; there is an increasing trend in the use of FL in quality, maintenance and fault diagnosis; and there are surprising gaps in the use of CBR and hybrid methods in operations management that offer opportunities for future research.

This is the largest and most comprehensive study to classify research on the use of AI in operations management to date. The survey and trends identified provide a useful reference point and directions for future research.

This paper aims to analyze energy and exergy analysis of solar-based intercooled and reheated gas turbine (GT) trigeneration cycle using parabolic trough solar collectors (PTC) with the use of MATLAB 2018.

In the first section of this paper, the solar-based GT is validated with the reference paper. According to the reference paper, the solar field is comprising 30 modules in series and 35 modules in parallel series, where a total of 1,050 modules of PTC are taken into consideration. In the second part of this paper, the hybridization of the solar, GT trigeneration cycle is analyzed and optimized. In the last section of this paper, the hybridization of solar, intercooled and reheated GT trigeneration systems is examined and compared.

The results examined the first section, the power produced by the cycle will be 37.34 MW at 0.5270 kg/s mass flow rate of the natural gas consumption and the efficiencies of energy and exergy will be 38.34% and 39.76%, respectively. The results examined in the second section, the power produced by the cycle will be 38.4 MW at 0.5270 kg/s mass flow rate of the natural gas consumption and accordingly the efficiency of energy and exergy is found to be 40.011% and 41.763%. Where in the last section, the power produced by the cycle will be 41.43 MW at 0.5270 kg/s mass flow rate of the natural gas consumption and the energy and exergy efficiencies will be 39.76% and 40.924%, respectively.

The author confirms that this study is original and has neither been published elsewhere nor it is currently under consideration for publication elsewhere.