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Detailed results of numerical calculations of transient, 2D incompressible flow around and in the wake of a square prism at Re = 100, 200 and 500 are presented. An implicit finite‐difference operator‐splitting method, a version of the known SIMPLEC‐like method on a staggered grid, is described. Appropriate theoretical results are presented. The method has second‐order accuracy in space, conserving mass, momentum and kinetic energy. A new modification of the multigrid method is employed to solve the elliptic pressure problem. Calculations are performed on a sequence of spatial grids with up to 401 × 321 grid points, at sequentially halved time steps to ensure grid‐independent results. Three types of flow are shown to exist at Re = 500: a steady‐state unstable flow and two which are transient, fully periodic and asymmetric about the centre line but mirror symmetric to each other. Discrete frequency spectra of drag and lift coefficients are presented.

The purpose of this paper is to numerically investigate the influence of corner radius on flow past a square cylinder at a Reynolds number 500.

Six models were studied, for R/D=0 (square cylinder), 0.1, 0.2, 0.3, 0.4, and 0.5 (circular cylinder), where R is the corner radius and D is the characteristic dimension of the body. The transient two-dimensional (2D) laminar and large eddy simulations (LES) models were employed using finite volume code. The Strouhal number, mean drag coefficient (C_D), and root mean square (RMS) value of lift coefficient (C_L,RMS), for different R/D values, were computed and compared with experimental and other numerical results.

The computational results showed good agreement with previously published results for a Reynolds number, Re=500. It was found that the corner effect on a square cylinder greatly influences the flow characteristics around the cylinder. Results indicate that, as the corner radius ratio, R/D, increases, the Strouhal number increases rapidly for R/D=0-0.2, and then gradually rises between R/D=0.2 and 0.5. The minimum values of the mean drag coefficient and the RMS value of lift coefficient were found around R/D=0.2, which is verified by the time averaged streamwise velocity deficit profile.

On the basis of the numerical results, it is concluded that rounded corners on a square cylinder are useful in reducing the drag and lift forces generated behind a cylinder. Finally, it is suggested that with a rounded corner ratio of around R/D=0.2, the drag and oscillation of the cylinder can be greatly reduced, as compared to circular and square cylinders.

This research aims to update the literature about the importance of reliability in supply chain (SC) and to find out the SC determinants.

This research surveys while contributing to the academic grasp of supply chain reliability (SCR) concepts. The study found 45 peer-reviewed publications using a structured survey technique with a four-step filtering process. The filtering process includes data reduction processes such as an evaluation of abstract and conclusion. The filtered study focuses on SCR and its determinants.

One of the major findings is that most of the study has focused on mathematical and conceptual studies. Also, this study provides the answer to a question like how can reliability be better accepted and evolved within the SC after finding the determinants of SCR.

The observed methodological gap in understanding and development of SCR was identified and classified into three categories: mathematical, conceptual and empirical studies (case studies and survey’s mainly). This research will aid academics in developing and understanding the determinants of SCR.

The purpose of this paper is to focus on the variation of wake structures and aerodynamic forces with changes in the cylinder corner radius and orientation.

Numerical simulations were performed for flow past a square cylinder with different corner radii placed at an angle to the incoming flow. In the present study, the rounded corner ratio R/D=0 (square cylinder), 0.1, 0.2, 0.3, and 0.4 (where R is the corner radius and D is the characteristic dimension of the body) and the angle of incidence α in the range of 0°-45° were considered.

The numerical model was validated by comparing the present results with results in the available literature, and they were found to be in good agreement. The critical incidence angle for the rounded corner cylinder – corresponding to the minimum mean drag coefficient (C _D ), the minimum root mean square value of the lift coefficient C _L,RMS), and the maximum Strouhal number – shifted to a lower incidence angle compared with the sharp corner square cylinder. The minimum drag and lift coefficient at R/D=0 were observed for the critical incidence angle α_cri=12°, whereas for R/D=0.1-0.4, the minimum drag and lift coefficient were found to be within the range of 5°-10° for α.

The presented results shows the importance of the incidence angle and rounded corners of the square cylinder for reduction of aerodynamic forces. The two parameters support the shear layer flow reattachment on the lateral surface of the cylinder, have a strong correlation with the reduction of the wake width, and hence reduced the values of C _D and C _L .

This paper presents a framework for understanding and analyzing the productivity of service workers. Based on findings in the multidisciplinary literature, it provides a working model for services managers that: recognizes that the definition of productivity may vary across service jobs, acknowledges that there are different levers for maximizing productivity in different contexts, and indicates that managing productivity needs to be viewed as a task for marketing, not just the organization's internal functions. The purview and implications of each component of the framework are discussed, together with some marketing‐based suggestions for productivity improvement.

The purpose of the work is development a novel of hydro-vibration technology for the formation of hats from fabrics, which will expand the functionalities of application of various fabrics.

The work is based on a novel technology of forming hats from different fabrics with the use of liquid-active working environment (LAWE). This hydro-vibration technology is characterized by high efficiency, productivity, manufacturability and potential opportunities when compared to existing technologies. This allows expanding its range of applications and increase functionality.

In the article, hydro-vibration technology is developed for the formation of hats from fabrics. As a result of the experiment, regression dependences of the shape stability coefficient on the formation factors having a close correlation were obtained. The performed optimization allowed determining the optimal values of technological parameters of the vibroforming process from fabrics: LAWE pressure 0.26 MPa, vibration frequency LAWE 4.3 Hz, forming time 74 s.

The use of developed hydro-vibration technology has great practical significance in the textile industry. This technology increases labor productivity and reduces the cost of production of hats due to its high efficiency. Increased efficiency is provided by the use of special equipment, methods and optimal parameters of the hats formation. With sufficient refinement, the developed technology can be applied to other technological processes.

Originality of the work is using liquid-actin working environment at vibroforming of heads of headdresses from fabrics. It is determined that the use of LAWE is effective in the formation of hats. To ensure maximum plasticization of textile fibers in the fabric of the part and increase the force field, it is developed a novel hydro-vibration technology of forming the heads of hats from fabrics.

A new approach was suggested for creating nano-dimensional materials based on water-soluble polymers. Nano-seized Al-contained structures were synthesized; such structures were screened by a cover of sodium-carboxymethylcellulose by heating up to 70-80 degrees of Celsius of a sodium-carboxymethylcellulose's polymere with Al microparticles with dimension less than 20 mkm. Morphological features of created composites were researched. It was established that agglomerates of received particles were reached values of 300-600 nm and consisted of tubular types' structures with dimensions 80-100 nm.

This paper attempts to develop a hybrid cause and effect diagram (CED) and interpretative structural model (ISM) for root cause analysis in quality management. The proposed model overcomes the weakness of the CED in reliably articulating hierarchical cause–effect Relationships.

A focus group discussion (FGD) among quality experts in the case company to establish relationships between the determined causes.

The hybridization of the CED and ISM allowed the causes to be ordered more clearly to determine potential root causes as well as presenting these causes more comprehensively.

The paper has been one of the very few attempts to improve the CED approach. As such, this paper employs the ability of the ISM to order concepts in a hierarchical structure, which is useful in determining root causes.

Seeking to build an objective scientific approach to psychiatry, American psychiatrists, physiologists, and psychologists began to turn to the conditional reflex method of Ivan Pavlov from the late 1920s. The generation of “neurotic” animals in the laboratory was critical to the emergence of a new experimental psychiatry in the United States. To understand the development of this field of research, the chapter will draw first on Mary Morgan’s identification of the mediatory and intermediary role of models and their ability to surprise and generate new questions, and second, upon her recent work on narratives in science. It will argue that it was through discursive and descriptive techniques that traced over time the tangled and interconnected lives of experimental subjects, that such elements of unpredictability in the animal laboratory were transformed into tools of research and put to disciplinary uses, promoting the clinical relevance of this new objective approach to psychiatric medicine.

The purpose of this paper is the study of the electro-vortex flow (EVF) as well as heating and melting processes for mini industrial direct current electric arc furnace (DC EAF).

A mini DC EAF was designed, manufactured and installed to study the industrial processes of heating and melting a small amount of melt, being 4.6 kg of steel in the case under study. Numerical modelling of metal melting was performed using the enthalpy and porosity approach at equal values and non-equal values of the solidus and liquidus temperatures of the metal. The EVF of the liquid phase of metal was computed using the large eddy simulation model of turbulence. Melt temperature measurements were made using an infrared camera and a probe with a thermocouple sensor. The melt speed was estimated by observing the movement of particles at the top surface of melt.

The thermal flux for metal heating and melting, which is supplied through an arc spot at the top surface of metal, is estimated using the thermal balance of the furnace at melting point. The melting time was estimated using numerical modelling of heating and melting of metal. The process started at room temperature and finished once whole volume of metal was molten. The evolution of the solid/melt phase boundary as well as evolution of EVF patterns of the melt was studied.

Numerical studies of heating and melting processes in metal were performed in the case of intensive liquid phase turbulent circulation due to the Lorentz force in the melt, which results from the interaction of electrical current with a self-magnetic field.