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This paper aims to tackle the problem of thermo‐solutal convection and macrosegregation during ingot solidification of metal alloys. Complex flow structures associated with the development of channels segregate and sharp gradients in the solutal field call for the implementation of accurate methods for numerical modeling of alloy solidification. In particular, the solute transport equation is convection dominated and requires special non‐oscillarity type high‐order schemes to handle the regions of channels segregates.

In the present study, a time‐splitting approach has been adopted to separately handle solute advection and diffusion. This splitting technique allows the application of accurate total variation dimensioning (TVD) schemes for solution of solute advection. Applications of second‐order Lax‐Wendroff TVD SUPERBEE and fifth‐order weighted essentially non‐oscillatory (WENO) schemes are described in the present article. Classical numerical solution of solute transport using hybrid and central‐difference schemes are also employed for the purpose of comparisons. Numerical simulations for solidification of Pb‐18%Sn in a two‐dimensional rectangular cavity have been carried out using different numerical schemes.

Numerical results show the difficulty of obtaining grid‐independent solutions with respect to local details in the region of channels. Grid convergence patterns and numerical uncertainty are found to be dependent on the applied scheme. In general, the first‐order hybrid scheme is diffusive and under predicts the formation of channels. The second‐order central‐difference scheme brings about oscillations with possible non‐physical extremes of solute composition in the region of channel segregates due to sharp gradients in the solutal field. The results obtained using TVD and WENO schemes contain no oscillations and show an excellent capture of channels formation and resolution of the interface between solute‐rich and depleted bands. Different stages of channels formation are followed by analyzing thermo‐solutal convection and macrosegregation at different times during solidification.

Accurate prediction of local variation in the solutal and flow fields in the channels regions requires grid refinement up to scales in the order of microscopic dendrite arm spacing. This imposes limitations in terms of large computational time and applicability of available macroscopic models based on classical volume‐averaging techniques.

The present study is very useful for numerical simulation of macrosegregation during ingot casting of metal alloys.

The paper provides the methodology and application of TVD schemes to predict channel segregates during columnar solidification of metal alloys. It also demonstrates the limitations of classical schemes for simulation of alloy solidification.

As the world moves toward globalization, new trends and applications are on the rise as an attempt to meet the ever-changing needs of consumers. In this sense, new technologies have been introduced as a means to differentiate the product and service offerings along with some emerging retailing perspectives. It is obvious that omnichannel retailing is cited as one of the emerging trends in marketing. In this globe, customer experience management plays a crucial role in establishing sustainable omnichannel retailing strategies. Considering all the variables in the business environment, it is seen that effective tools of omnichannel operations should well be implemented as a response to effectively compete in the business environment. This chapter reveals some of the major literature and applications in the context of omnichannel retailing whereby the most concern of interest is given to the importance of customer experience and its formation.

This study analyzes the blade channel vortices inside Francis runner with a particular focus on the identification of different types of vortices and their causes.

A single-flow passage of the Francis runner with refined mesh and periodic boundary conditions was used for the numerical simulation to reduce the computational resource. The steady-state Reynolds-averaged Navier–Stokes equations closed with the k-ω shear–stress transport (SST) turbulence model were solved by ANSYS CFX to determine the flow field. The vortices were identified by the second largest eigenvalue of velocity.

Four types of vortices were identified inside the runner. Three types were related to the inlet flow. The last one (Type 4) was caused by the reversed flow near the runner crown and had the lowest pressure inside the core near the runner outlet. Thus, in the blade channel vortex inception line, Type 4 vortex would appear earlier than the other three ones. Besides, the Type 4 vortex emerged from the crown and shed toward the blade-trailing edge. And its location moved from near the crown down to near the band when the unit speed increased or unit discharge decreased.

Although the refined mesh was used and the main vortices in the Francis runner were well predicted, the current mesh is not enough to accurately predict the lowest pressure in the channel vortex core.

This knowledge is instructive in the runner blade design and troubleshooting related to the channel vortex.

This study gives an overview of the main observed blade channel vortices and their causes, and points out the important role the reversed flow plays in the formation of blade channel vortices. This knowledge is instructive in the runner blade design and troubleshooting related to blade channel vortices.

When a multi component alloy solidifies the redistribution of solute components leads to the formation of macrosegregation patterns. Blending ideas from a number of recent publications the purpose of this paper is to provide a “best practice” on how grid convergence of a given macrosegregation simulation can be measured and determined.

The best practice is arrived at by considering a benchmark problem consisting of a 2D-casting simulation of an idealized Al-4.5%Cu alloy in a side cooled square (76×76 mm) cavity. The model for this simulation is based on a mixture treatment of the relevant heat and mass transfer equations. Simulations are made using three increasingly refined grid sizes.

The best practice to determine grid resolution involves two steps: first, a visual evaluation of predicted segregation images leading to the evaluation of solute profiles along selected transects; and second, the construction of a cumulative distribution function (CDF) of the predicted segregation field. On application to the benchmark problem, it is concluded that current computer resources are insufficient to grid resolve macrosegregation patterns but that the CDF provides a useful signal of the nature of macrosegregation in a given system.

The benchmark is chosen to be representative. Exact convergence behavior, however, may depend on the system chosen.

In addition to establishing a best practice for measuring grid resolution of macrosegregation simulations the work also highlights, even in the absence of complete grid convergence, how the recently proposed CDF treatment can inform solidification modeling and process understanding.

This research, based on the idea of contingency fit, attempts to construct a strategic selection system to select the best fit competency of channel strategic selection by using neuro‐fuzzy technique.

Neuro‐fuzzy technique is used.

In addition to, providing a concrete bilateral solution to select the right and better fit competency of channel strategy and giving an alternative way to explain fit, this strategic selection system can also be used as a competency diagnosis system for channel members in the supply chain organization, providing clues for further channel performance promotion and channel modernization.

Through the literature and construction of strategy channel satisfaction model (SCSM) concepts and ideas, an empirical study of the Asian Commerce Community meet distribution channel relationships will pose an Asian developed channel modernization perspective of SCSM to discuss the critical marketing strategy selection for the traditional orient “commercial channel”.

This article applies the theory of coalition formation in triads to channels of distribution. The theory explains alternative power strategies of weaker (smaller) channel members to dominance by more powerful channel entities. Six pre‐coalition situations are examined to aid in predicting the possible conditions that may form, given an uneven distribution of power in the channel system. This type of analysis could be used to predict disadvantageous power combinations in the channels of distribution to the overall macro effectiveness of the channel system.

The purpose of this paper is to present the embossing as a replication technique for structuring fuel channels in the anode-supported solid oxide fuel cells (SOFCs).

The anode laminate, which was exposed to embossing, consisted of eight layers of isostatic pressed Ni-yttria-stabilized zirconia tapes (Ni-YSZ). Preheating the mould and soaking the laminate in the plasticizer was applied before structuring of the channels to soften the laminate. Compressing tests were carried out to investigate the embossing ability of the Ni-YSZ laminate and to find the optimal processing parameters. Embossing was carried out with a testing machine, and the samples were exposed to embossing forces in the range up 20 kN with a certain speed of compression and a dwell time.

The embossing parameters (force of compression, speed of compression and dwell time) suitable for proper fuel channels formation were established. Shapes, profiles and dimensions of the embossed channels were analysed and compared to the micromachined channels. The model of the SOFC with embossed fuel channels was completed, and its current-voltage characteristic was measured.

Experiments proved that embossing can be the alternative method for patterning fuel microchannels in SOFCs. Embossing simplifies the process of fuel channel formation and reduces the time of SOFC fabrication. It is necessary to improve the geometry and quality of the mould formation to make the fuel channels deeper and of better surface finish.

The purpose of this paper is to provide a guidance for boundary personnel regarding how to use influence strategies to increase channel satisfaction across relationship development process.

This paper investigates the use of influence strategies and their impact on channel satisfaction across formation, operation, and maintenance stage from Das and Teng's viewpoint. The sample from Taiwanese manufacture in electronic, information and motors industry involving buyer‐supplier relationships, and asks respondents (sales manager) to select a newer customer to complete a questionnaire for enable sufficient responses to be obtained, representing different stages of the buyer‐supplier relationship.

The results indicate that the frequency of requests, promises, legalistic pleas, and threat strategies differ significantly among relationship stages. Additionally, information exchange, recommendations, and request strategies have dramatic effect on channel satisfaction across different stages.

This paper proposes the most appropriate model for channel managers to apply influence strategies judiciously in each relationship stage.

No other research analyzes the formation of overall satisfaction across channels, including the reciprocal interactions between store and website satisfaction and the factors that moderate them. Therefore, the aim of the present study is to examine how overall customer satisfaction is formed from the image and perceived congruence of the two main existing channels and the satisfaction induced by each.

The online study covers 909 customers of a French mortar-to-click retailer specializing in women's and children's clothing. The conceptual model incorporates reciprocal interdependence between store satisfaction and website satisfaction. This model is tested using the procedure specific to non-recursive structural equation model.

Overall satisfaction with the retailer is not only generated by satisfaction with the store and the website, but also directly and indirectly by the image of each channel. The contribution of the variables depends on the personal and situational characteristics of the customer. Not only is the relationship confirmed from store satisfaction to website satisfaction, but for the first time, in rarer cases the reverse is also observed. On the other hand, while the perceived congruence of channels can improve satisfaction with the channel for certain types of customers, in other cases the congruence can also worsen customers' overall satisfaction.

The detailed analysis of the formation of this satisfaction shows the pre-eminence of the customer over the retailer's initiatives. A retailer may facilitate or encourage virtuous interaction between retailer's channels by making the transfer of information and products more fluid (click and collect for example); but in the end, the customer is the one who decides whether or not to bring the channels closer together.

Contrary to what the literature assumes, in some cases, the retailer's attempt to integrate the channels may even reduce overall satisfaction if customers do not want this integration, just as a high level of satisfaction on the website can reduce in-store satisfaction.

This paper aims to study the breakdown, oscillation and vanishing of the discharge channel and its influence on crater formation with simulation and experimental methods. The experiment results verified the effect of the oscillating characteristics of the discharge channel on the shape of the crater.

A mathematical model that considers the magnetohydrodynamics (MHD) and the discharge channel oscillation was established. The micro process of discharging based on magnetic-fluid coupling during electrical discharge machining (EDM) was simulated. The breakdown, oscillation and vanishing stage of the discharge channel were analyzed, and the crater after machining was obtained. Finally, a single-pulse discharge experiment during EDM was conducted to verify the simulation model.

During the breakdown of the discharge channel, the electrons move towards the center of the discharge channel. The electrons at the end diverge due to the action of water resistance, making the discharge channel appear wide at both ends and narrow in the middle, showing the pinch effect. Due to the mutual attraction of electrons and positive ions in the channel, the transverse oscillation of the discharge channel is shown on the micro level. Therefore, the position of the discharge point on the workpiece changes. The longitudinal oscillation in the discharge channel causes the molten pool on the workpiece to be ejected due to the changing pressure. The experimental results show that the shape of the crater is similar to that in the simulation, which verifies the correctness of the simulation results and also proves that the crater generated by the single pulse discharge is essentially the result of the interaction between transverse wave and longitudinal wave.

In this paper, the simulation of the discharge breakdown process in EDM was carried out, and a new mathematical model that considers the MHD and the discharge channel oscillation was established. Based on the MHD module, the discharge breakdown, oscillation and vanishing stages were simulated, and the velocity field and pressure field in the discharge area were obtained.