*2.4. Exergoeconomic Analysis*

The exergoeconomic analysis consists of the formulation of a cost balance and its auxiliary equations at a component level, for each component of the process. The general cost balance [17] is shown in Equation (20) where *cout* and *cin* represent the costs of the outflows and inflows respectively, *cw*,*k* represents the cost rate related with the work and . *Zk* represents the investment cost of each component. Table 2 shows the cost balance of each component present in the system.

$$
\sum\_{k} c\_{q,k} \dot{E}\_{q,k} + c\_{w,k} \dot{\mathcal{W}}\_{k} + \sum\_{\text{in}} c\_{\text{in}} \dot{E}\_{\text{in}} - \sum\_{\text{out}} c\_{\text{out}} \dot{E}\_{\text{out}} - c\_{D,k} \dot{E}\_{D,k} + \dot{Z}\_{k} = 0 \tag{20}
$$

The cost balance can be written in terms of the fuel and product formulation [28] as is shown in Equations (21) and (22).

$$
\dot{\mathcal{C}}\_{P,k} = \dot{\mathcal{C}}\_{F,k} + \dot{\mathcal{Z}}\_{k} - \dot{\mathcal{C}}\_{D,k} \tag{21}
$$

$$
\omega\_{P,k}\dot{E}\_{P,k} = \omega\_{F,k}\dot{E}\_{F,k} + \dot{Z}\_k - \dot{C}\_{D,k} \tag{22}
$$

.

where *CP*,*k* is the product cost rate, *CF*,*k* is the fuel cost rate, and *CD*,*k* is the cost rate associated with the destroyed exergy for each component.

.

The exergy destroyed in the *k*-th component has an associated cost rate . *CD*,*k* that can be calculated in terms of the cost of the additional fuel (*cF*,*k*) that needs to be supplied to this component to cover the exergy destruction and to generate the same exergy flow rate of the product, when . *EP*,*k* stay constant (Equation (23)) [17]. Table 4 shows the cost balance of each component present in the system.

$$
\dot{\mathcal{C}}\_{D,k} = c\_{F,k} \dot{E}\_{D,k} \tag{23}
$$

**Table 4.** Cost balance equations and auxiliary equations for exergy costs of the system.

.

There are some non-energetic costs used in the calculations of the cost balance of each component. In the boiler, the fuel used to generate vapor was fuel oil 6. The price of the liquid fuel (stream 49) was

\$1.07 per gallon [32]. The potable water (stream 48) had a cost of \$0.53 per cubic meter [33]. The price of carbon dioxide (stream 1) injected into the coffee extract was \$24.22 per kg.

The variable . *Zk* was calculated as the sum of capital investment ( . *Z CI k* ) and operation and maintenance costs ( . *Z OM k* ) for each component, as is shown in Equation (24) [17].

$$
\dot{Z}\_k = \dot{Z}\_k^{\text{OM}} + \dot{Z}\_k^{\text{CI}} \tag{24}
$$

The capital investment for each component can be calculated by using Equation (25) [17]:

$$\dot{Z}\_k^{CI} = \frac{\text{PEC}\_k \* \text{CRF}}{\tau} \tag{25}$$

where *PECk* is the purchase price of the kth component and τ is the number of annual operating hours (24 h per day, 365 days per year). It was assumed that the ordinary annuities transaction occurs at the end of each time interval, thus the *CRF* (capital recovery factor) could be obtained using Equation (26) [17], where *ieff* is the interest rate (10%), and n is the lifetime of the system (20 years).

$$\text{CRF} = \frac{i\_{eff} \* \left(1 + i\_{eff}\right)^n}{\left(1 + i\_{eff}\right)^n - 1} \tag{26}$$

The rate of operation and maintenance costs ( . *Z OM k* ) can be calculated by using Equation (27). The operation and maintenance cost (OMCk) of each component is determined by using Equation (28), which is a close approximation used by Bejan et al [17]. The constant-escalation levelization factor (CELF) was determined by using Equation (29), which depends on the factor *kOMC* defined by Equation (30) [17]. For the nominal escalation rate (*rOM*), it was assumed that all costs except fuel costs and the values of by-products change annually with the constant average inflation rate of 4% [17].

$$\dot{Z}\_k^{\text{OM}} = \frac{\text{OMC}\_k \* \text{CLEF}\_{\text{OM}}}{\tau} \tag{27}$$

$$\text{OMC}\_k = 0.2 \ast \text{PEC}\_k \tag{28}$$

$$\text{CELF}\_{\text{OM}} = \frac{k\_{\text{OMC}} \* (1 - k\_{\text{OMC}}^{\*}) \* \text{CRF}}{(1 - k\_{\text{OMC}})} \tag{29}$$

$$k\_{\rm OMC} = \frac{1 + r\_{\rm OM}}{1 + i\_{eff}} \tag{30}$$

For a better interpretation of the results, the exergoeconomic factor (*fk*) and relative cost difference (*rk*) were determined. The first factor represents the relationship between the investment cost and the total operating cost rate, while the *rk* represents the increase of the specific exergy cost in a component divided by the specific exergy cost of the fuel.

$$f\_k = \frac{\dot{Z}\_k}{\dot{Z}\_k + \dot{\mathcal{C}}\_{D,k}} \tag{31}$$

$$r\_k = \frac{c\_{P,k} - c\_{F,k}}{c\_{F,k}} \tag{32}$$

## *2.5. Advanced Exergoeconomic Analysis*

The unavoidable ( . *C UN D*,*k* ) and avoidable cost ( . *C AV D*,*k*) associated with exergy destruction were calculated using Equations (33) and (34). The unavoidable ( . *Z UN k* ) and avoidable investment cost rates ( . *Z AV k* ) were calculated by using Equations (35) and (36). The relation between the investment cost rate and the exergy product rate ( . *Zk*/ . *EP*)*UNk* was estimated by using the unavoidable cost conditions presented in Table 4. For the heat exchangers, a Pro/II ®simulator was used to estimate the new heat transfer area based on the minimum temperature difference.

$$
\dot{\mathbf{C}}\_{D,k}^{\rm LIN} = c\_{F,k} \dot{E}\_{D,k}^{\rm INN} \tag{33}
$$

$$
\dot{\bar{C}}\_{D,k}^{AV} = \dot{\bar{C}}\_{D,k} - \dot{\bar{C}}\_{D,k}^{AV} \tag{34}
$$

$$
\dot{Z}\_k^{\text{LIN}} = \dot{E}\_{P,k} \left(\frac{\dot{Z}\_k}{\dot{E}\_P}\right)\_k^{\text{LIN}} \tag{35}
$$

$$
\dot{Z}\_k^{AV} = \dot{Z}\_k - \dot{Z}\_k^{lIN} \tag{36}
$$

## **3. Results and Discussions**


**4. Discussion**

In the model we developed for this group of women who had undergone TVT there is one indirect sequence of influences affecting HRQOL: Neurotism (-) - CISS task style (-) - HRQOL; that is, a lower level of Neurotism leads to the choice of the task-oriented style, and the less preference for this style, the higher the evaluation of HRQOL.

According to the assumptions of McCrea and Costa (2005), Neurotism is a personality dimension that reflects the level of emotional adaptation: the higher the score, the greater the susceptibility to experiencing such negative emotions as fear, anger, guilt, the higher the sensitivity to psychological stress, and by the same token the harder it is to cope with a difficult situation, which can have an impact on the subjective lowering of HRQOL. The impact of negative emotions on the possibility of adaptation has been confirmed in many studies.

The indirect influence that our model shows Neurotism exerting on HRQOL is consistent with the findings of other researchers (cf. Ferrie et al., 1984; Norton et al., 1990), who have reported that those women with USI function better who are characterized by a lower level of Neurotism, and with research results indicating that USI patients with low Neurotism scores show better outcomes after surgical treatment (Berglund et al., 1997). It is reasonable to assume that improved psychological functioning has a positive effect on HRQOL.

The model also shows a relationship between HRQOL and the task-oriented coping style, which may result from the possibility of overcoming the symptoms, which are much less in subjective evaluation after TVT. At the same time, the model shows a relationship between less frequent use of the task-oriented style and a higher level of HRQOL. It may seem that this dependence should be rather the reverse, since, in the opinion of many researchers (Janssen et al., 2001) coping with the symptoms of urinary incontinence requires a task-oriented approach.

In the literature the most effective methods of coping with the symptoms of urinary incontinence are thought to include a restriction in the intake of fluids, very regular urination, making toilet maps (e.g. on the road from work to home), using single-use sanitary pads and napkins, and keeping a log of urination (Kinn & Zaar, 1998; Fitzerald et al., 2001; Janssen et al., 2001). These techniques correspond, interestingly enough, with both a task-oriented approach and an avoidance approach (all forms of restriction, such as avoiding fluids), though this is seldom stated directly. This may be at least a partial explanation of the dependency we found. It should also be emphasized that many researchers (e.g. Czapiński, 1994; Bidzan et al., 2004b) emphasize the advantages gained from combining styles of coping with the problem, e.g. task-oriented with emotion, since in this case the patient begins to take some action: to undergo treatment, to comply with physician's orders, to search for their own ways of coping with the problem (using also support networks), or finally to decide on surgery. In other words, they cope more effectively with the disease (cf. Shaw, 2001), which can have a favorable impact on their evaluation of HRQOL. The task-oriented approach alone, though it seems more efficient, is not optimal, and when it is the only strategy used, it can lower HRQOL.


**17. Forces of gravity**

In addition to the attraction force of the earth mass, there is another force which effect the rotated earth called (Centrifugal Force). This force created due to the continuous rotation of the earth around its axis. The force related to the radius of rotation and the square of the angular velocity:-

Therefore

The total gravity force = Attraction Force + Centrifugal Force (FC)

$$F\mathbf{c}\_p = r\mathbf{w}^2 \text{COS}\boldsymbol{\theta} \tag{60}$$

P = point at the earth surface. ϴ = latitude Centrifugal force *Fc p* α r ω2

$$Fcp = mra^2\tag{61}$$

Where m = mass

r = radius of rotation *ω* ¼ angular velocity

$$\therefore \text{--} \mathbf{g} = -G \left[ \frac{1}{r^2} dm + m r o^2 \right. \tag{62}$$

The Centrifugal force contribute the total gravity effect on the earth surface by about 10�7 –10�8 gal. The force have its maximum value at the equator of the earth and reach zero value at the poles of the earth.

The absolute gravity value at the equator is about 978 gal, while its value at poles about 983 gal, The difference in gravity value between the equator and pole is range between (5.17 gal) or (5170 mgal).


*3.3. Bending Test*

Three-point bending tests were conducted using the same Hounsfield tensometer previously used for the tensile tests. The performance of the bending test was based on the ASTM E290-97a standard. There were six rectangular-shaped specimens prepared for bending tests. The bending tests were performed on the face and the root of the joint. The three specimens presented in Figure 8 show the face of the joint (the surface that was in contact with the tool shoulder) and another three presented in Figure 9 show the root of the joint (the surface that was in contact with the backplate). For comparative purposes, the bending test was also performed on parent materials.

**Figure 8.** Bending specimens, (**a**) face; (**b**) root.