Extended DuPont model

it allows users to isolate what is driving ROA and ROE. Are they driven by the company s ability to earn high profit margins (a measure of operating efficiency), or from its efficient use of assets (measured by total asset turnover), or from its use of debt financing (measured by financial leverage, equity multiplier)  

Second, the DuPont model can be used to conduct what if scenarios. Should capacity be increased and new workers hired for expected sales growth Inserting expected wages and sales revenue into the DuPont model, immediately demonstrates how ROA and ROE change. In addition, if management states that its goal is to increase ROE by 10%, the DuPont model can help determine how should the goal be accomplished and what operational or supply chain activities will contribute. 

the DuPont model can be used as a risk-planning tool. What if a supplier goes out of business, so a new supplier is needed and shipments must be expedited. How will these changes impact ROE  

Finally, the DuPont model can be used as a sales instrument in business-to-business (B2B) commerce. Prospective customers can see how their ROE could improve if they buy one company s service or product instead of a competitor s. 

If scenario number two occurs, two outcomes are likely (1) your revenue declines due to lost sales and (2) your costs increase from finding a new supplier, spending additional time working with your new supplier to coordinate processes and procedures, and from expediting shipments to meet current sales obligations. In this scenario 

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For an extended review of experimental work on mini and microchannels, the reader is refered to the Thome (2004) and Kandlikar (2002) papers. This brief review covers a representative selection of heat transfer studies in minichannels and its aim is to illustrate the tendencies observed in the presented data. Recently Kandlikar (2004) developed a new general correlation adapted to minichannels which gives very good results for low qualities but fails to take dry-out into account, as noted by the author in question. Lately Thome et al. (2004) and Dupont et al. (2004) proposed a semi-empirical three zone model which is the only published work to predict the unique trends observed in minichannels. In this model the dominant boiling mechanism is the evaporation of the liquid film pressed under confined bubbles. 

A plausible conjecture, supported by preliminary observations (Dupont, 1993 G. Dupont A. Goldbeter, unpublished results) is that complex oscillations would result from the existence of two oscillatory processes characterized by different time scales (i) a slow Ca variation arising from the reversible desensitization of the IP3 receptor, and (ii) fast Ca " transients occurring on top of that periodic variation as a result of the mechanism based on CICR. However, the latter mechanism can still readily generate simple periodic oscillations in Ca in such an extended model as illustrated by the results shown in fig. 9.23, these oscillations are passively accompanied by a simple, periodic variation in IP3 and in the fraction of nondesensitized IP3 receptors. 

Fig. 9.23. Oscillations of cytosolic Ca (in p,M, solid line) following sustained stimulation by an external signal in the extended version of the model based on Ca -induced Ca release (CICR). Also represented are the normalized concentration of IP3 (dashed line) and the fraction of active, nondesensitized IP3 receptors (dotted line), which are both driven here passively by oscillations based on CICR. In the extended model, which contains the five variables listed in table 9.1, IP3-mediated release of Ca" and CICR are supplemented with the following additional regulatory processes activation of IP3 synthesis by Ca, and desensitization of the IP3 receptor induced by IP3 (as in the present simulations) or cytosolic Ca (Dupont et al, 1991).

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