Search results

This study aims to examine the flow characteristics of Ree–Eyring fluid between two rotating disks. The characteristics of heat transfer are discussed in presence of viscous dissipation, heat source/sink and nonlinear radiative heat flux.

Nonlinear flow expressions lead to ordinary ones through adequate similarity transformations. The ordinary differential system has been tackled through optimal homotopic method. The impact of different flow variables on the velocity field, entropy generation rate and temperature fields is graphically discussed. The surface drag force and heat transfer rate are numerically examined via various pertinent parameters.

By minimization of values of stretching parameter and Brinkman number, the entropy generation rate can be controlled. The entropy generation rate enhances for higher values of magnetic parameter, while the Bejan number is decreased via magnetic parameter.

No such work is yet published in the literature.

This paper aims to address the flow features of Ree–Eyring fluid between two rotating disks subject to the magnetic field. Heat transfer features are discussed through viscous dissipation and nonlinear thermal radiation. Impact of thermophoresis and Brownian movement are elaborated. Physical characteristics of entropy generation optimization in nanofluid with homogeneous and heterogeneous chemical reaction are discussed.

The nonlinear system leads to ordinary one through the implementation of adequate transformation and then tackled analytically for a convergent series solution by homotopy analysis method.

The prime objective of the present research has been given to investigate entropy generation in Ree–Eyring fluid flow between two rotating disks subjected to the magnetic field. Vital features, namely, Brownian motion and thermophoresis have been addressed. Total entropy rate is computed using the second law of thermodynamics.

No such work yet exists in the literature.

Hybrid nanofluids are of significant engrossment for their considerable heat transport rate. The steady flow of an incompressible viscous electrically conducted hybrid nanofluid is considered over a rotating disk under a magnetic field. Titanium oxide (TiO₂) and ferrous (CoFe₂O₄) nanoparticles are used with their physical properties and water is considered as host liquid. The purpose of this paper is to analyze how hydrothermal integrity varies for hybrid nanosuspension over a spinning disk in the presence of magnetic orientation.

Governing equations with boundary conditions are transformed by similarity transformations and then solved numerically with RK-4 method. A comparison of linear and nonlinear thermal radiation for the above-mentioned parameters is taken and the efficiency of nonlinear radiation is established, the same over nanofluid and hybrid nanofluid is also discussed. Heat lines are observed and discussed for various parameters like magnetic field, concentration, suction and injection parameter, radiation effect and Prandtl number.

Suction and increasing nanoparticle concentration foster the radial and cross-radial velocities, whereas magnetization and injection confirm the reverse trend. The rate of increment of radial friction is quite higher for the usual nanosuspension. The calculated data demonstrate that the rate for hybrid nanofluid is 8.97 percent, whereas for nanofluid it is 15.06 percent. Double-particle suspension amplifies the thermal efficiency than that of a single particle. Magnetic and radiation parameters aid the heat transfer, but nanoparticle concentration and suction explore the opposite syndrome. The magnetic parameter increases the heat transport at 36.58 and 42.71 percent for nonlinear radiation and hybrid nanosuspension, respectively.

Nonlinear radiation gives a higher heat transport rate and for the radiation parameter it is almost double. This result is very significant for comparison between linear and nonlinear radiation. Heat lines may be observed by taking different nanoparticle materials to get some diverse result. Hydrothermal study of such hybrid liquid is noteworthy because outcomes of this study will aid nanoscience and nanotechnology in an efficient way.

In industrialised economies, frugal innovation is increasingly becoming a strategic business requirement due to consumer demand for high-quality, reasonably priced and sustainable products. The present-day corporate leaders cannot afford to overlook this paradigm change. Frugal innovation enterprises are better positioned to overcome technological, financial, social and infrastructure constraints in emerging economies. However, little is known about how different actors and decision-makers perceive the challenges faced by family entrepreneurs in digitalising their entrepreneurial activities. Thus, this chapter aims to articulate the opportunities that can be potentially created for African family entrepreneurs and some challenges that can be anticipated when adopting disruptive digital technologies in their business enterprises. Using the social cognitive theory (SCT), interpretivism philosophy was adopted in this study. The authors utilised the interview guide to explore, probe and ask questions that addressed the objectives of the study. Snowball sampling was chosen for qualitative data collection, and the data were thematically presented. The population of the study was made up of family entrepreneurs in Harare Metropolitan Province in Zimbabwe; the saturation level determined the sample size. Twenty (20) participants were interviewed, as guided by the saturation point. A thematic approach was used to analyse participant's feedback. This study filled a critical gap considering that few studies have so far been conducted in this emerging area of family entrepreneurship. The chapter also highlights the opportunities that adoption of digital technologies can potentially unlock for African family entrepreneurs, once the identified obstructions have been successfully addressed.

The purpose of this paper is to explore the role that mobile technologies play in mobile workers’ efforts to manage the boundaries between work and non-work domains. Previous theories of work-life boundary management frame boundary management strategies as a range between the segmentation and integration of work-life domains, but fail to provide a satisfactory account of technology’s role.

The authors apply the concept of affordances, defined as the relationship between users’ abilities and features of mobile technology, in two field studies of a total of 25 mobile workers who used a variety of mobile devices and services.

The results demonstrate that the material features of mobile technologies offer five specific affordances that mobile workers use in managing work-life boundaries: mobility, connectedness, interoperability, identifiability and personalization. These affordances persist in their influence across time, despite their connection to different technology features.

The author found that mobile workers’ boundary management strategies do not fit comfortably along a linear segmentation-integration continuum. Rather, mobile workers establish a variety of personalized boundary management practices to match their particular situations. The authors speculate that mobile technology has core material properties that endure over time. The authors surmise that these material properties provide opportunities for users to interact with them in a manner to make the five affordances possible. Therefore, in the future, actors interacting with mobile devices to manage their work-life boundaries may experience affordances similar to those the authors observed because of the presence of the core material properties.

Operations managers need to consider where to manufacture, or outsource, their manufacturing activities. A factor in location choice is productivity differences at different locations. This study aims to focus on determining productivity at the shopfloor level since this is the place where the differences in productivity ultimately affect the international competition position.

Causes for international differences in productivity for an essentially equal production technology, with an essentially equal level of shopfloor skills are determined from case analysis.

It was found that working conditions, degree of centralization, the national attitude towards time, and the motivation of the workforce influence productivity.

Productivity is dependent on factors that are connected with the external environment. Consequently, companies can not assume that productivity levels will be the same when moving to another country.

The paper illustrates factors, some outside of the company's control, that affect productivity and therefore the cost of international production.

The purpose of this paper is to examine the claim that the application of human factors (HF) knowledge can improve both human well‐being and operations system (OS) performance.

A systematic review was conducted using a general and two specialist databases to identify empirical studies addressing both human and OS effects in examining manufacturing OS design aspects.

A total of 45 empirical studies were found, addressing both the human and system effects of OS (re)design. Of those studies providing clear directional effects, 95 percent showed a convergence between human effects and system effects (+, + or −,−), 5 percent showed a divergence of human and system effects (+,− or −,+). System effects included quality, productivity, implementation performance of new technologies, and also more “intangible” effects in terms of improved communication and co‐operation. Human effects included employee health, attitudes, physical workload, and “quality of working life”.

Future research should attend to both human and system outcomes in trying to determine optimal configurations for OSs as this appears to be a complex relationship with potential long‐term impact on operational performance.

The application of HF in OS design can support improvement in both employee well‐being and system performance in a number of manufacturing domains.

The paper outlines and documents a research and practice gap between the fields of HF and operations management research that has not been previously discussed in the management literature. This gap may be inhibiting the design of OSs with superior long‐term performance.

The purpose of this paper is to present a precise comparison between a pre-determined time rules and the evaluation performed with the help of a manual chronometer using data from a line assembly in an automotive industry besieged in the state of Paraná, Brazil. Nowadays, it is possible to verify several tools of measurement of task times, some taking less time and causing less wear of the evaluator than others, but not being in accordance with the real conditions of the workers of a certain industry.

The developed paper has its methodology based on two methods of time analysis, one of them being an adaptation of the MODular Arrangement of Predeterminated Time Standard (MODAPTS) method – called MODAPTS 2. This method is used by the industry in analyzed in this work and the other through the use of simple manual timing, through the digital timer, of the stages developed in a workstation.

The study shows that for each operation analyzed, thus presenting a situation of minimum waste, it becomes possible to judge which reasons exist for the operator during manual timekeeping not to reach the optimum times generated by the system of pre-determined times and movements (PMTSs) questioned.

This study is conducted on an automotive enterprise in a period of confidentiality, which means that only a single workstation is able to be studied. This means that the comparison obtained between the time measurements methods used, and the evaluation of the MODAPTS is carried out with the best possible movements and gestures, disregarding then that the wastes can still be postulated to the whole assembly line.

With the automation in industry, where assemble tasks are usually developed manually, it is believed possible to discard the option of measuring task times in its classic and manual form, using a timer, yet during this process, there will be variables that may not be considered by pre-determined measurements methodologies. The work developed by this paper presents different variables that are not examined by the methods of PMTS, not frequently seen in the literature, as well as the difference that occurs between the measurement of times with stopwatch and the use of PMTS, which, in its original form, disregards the wastes that the operator has in their movements.

Examines the product design and manufacturing literature to understand why consumer products of daily use often fail to provide the intended function to users’ satisfaction. The review shows that the bulk of published literature addressing functionality and functional representation deals with mechanical systems design, and there are issues that directly affect the consumer that are yet to be accommodated in current research in functional representation. The literature also reveals that very few of the product design support systems have been tested on real design cases, or have been developed and tested using real designers in manufacturing environments – this issue needs serious consideration if efficient designer aids are to be developed in the future. Also, there is relatively little that has been done to develop tools to evaluate alternative design solutions. It is also apparent from this review that the main research focus has been on providing function, rather than on ensuring function in a product that is eventually manufactured.