Actual Performance

It Is important to know how much each well produces or injects in order to identify productivity or injectivity changes in the wells, the cause of which may then be investigated. Also, for reservoir management purposes (Section 14.0) it is necessary to understand the distribution of volumes of fluids produced from and injected into the field. This data is input to the reservoir simulation model, and is used to check whether the actual performance agrees with the prediction, and to update the historical data in the model. Where actual and predicted results do not agree, an explanation is sought, and may lead to an adjustment of the model (e.g. re-defining pressure boundaries, or volumes of fluid in place). 

It is good practice to reviewa project on completion and record the reasons for departure between planned and actual performance. Where lessons can be learned, or opportunities exploited, they should be incorporated into project management guidelines. Some companies hold post project sessions with their contractors to explore better ways of handling particular issues, especially when there is an expectation of additional shared activities. 

Such an analysis of the Hterature for assigning reaction types to different reaction schemes definitely has merits. However, it does not say anything about the importance of a reaction type, such as how frequently it is actually performed in the laboratory. 

Practically all CNDO calculations are actually performed using the CNDO/ 2 method, which is an improved parameterization over the original CNDO/1 method. There is a CNDO/S method that is parameterized to reproduce electronic spectra. The CNDO/S method does yield improved prediction of excitation energies, but at the expense of the poorer prediction of molecular geometry. There have also been extensions of the CNDO/2 method to include elements with occupied d orbitals. These techniques have not seen widespread use due to the limited accuracy of results. 

As actually performed a 62% yield of a mixture of ortho and para nitration prod ucts has been obtained with an ortho-para ratio of about 1 3... 

Tables 2—5 Hst some typical properties or ranges of properties for the more common film and sheet products. Although these values are good for comparative purposes, actual performance tests are best to determine suitabiHty for use. Properties of multiple-layer films or sheets in laminar stmctures cannot always be predicted from values for the individual polymer layers. Use conditions of stress, temperature, humidity, and light exposure all strongly influence performance. Film and sheet manufacturers can recommend product combinations or variations that may provide significant performance advantages to the user.

The actual formulations used by the various companies engaged in the highly competitive air bag business are proprietary, and contain numerous additives to modify the actual performance of the air bag compositions. Many more changes are likely in this new industry. 

Sohds in either phase are sedimented to the underside of the disks and shde outward along the surfaces because of their density. The aggregated sohds must move by free settling from the outer edges of the disks to the bowl wall some may be reentrained into new feed material, and carried into the disk stack, which accounts in part for actual performance falling short of theoretical prediction. 

Formulation of effective corrosion-resistant coatings is made difficult by the lack of a laboratory test that can provide rehable predictions of field performance. The most widely used test is exposure in a salt fog chamber. It has been shown repeatedly, however, that the results of such tests do not correlate with actual performance (125). Outdoor exposure of panels can provide useful data, especially in locations where salt spray occurs, but predictions of performance are not always satisfactory (126). 

The reproducibility of test results between labs using the neutral salt spray tests has not been consistent, but the repeatability, within one lab, is better, and the test has value in comparing variations in coating systems. Correlation of hours of exposure in the salt spray test to actual performance of the plated part in service, even in marine atmospheres, is not consistent and usually avoided. A classic example is that cadmium deposits outlast zinc deposits on steel in salt spray tests and clean marine atmospheres, yet zinc outlasts cadmium when exposed to real, industrial atmospheres, because of the presence of sulfur-bearing corrodents in industrial environments. An important variable in salt spray testing is the position of the surface to be tested. Whereas the surface of test panels is specified to be 15—30° from the vertical (40), when salt spray testing chromated zinc-plated specimens, this range has appeared excessive (41). 

Gravity vessels are suitable for low-, medium-, and high-temperature operation in the last case, the housing will be lined completely with refrac tory brick. Dust-recoveiy equipment is minimized in this type of operation since the bed actually performs as a dust col-lec tor itself, and dust in the bed will not, in a successful application, exist in large quantities. 

Application The theoretical considerations that have been expounded should be used only for order-of-magnitude estimates, since a number of extraneous factors may enter into actual performance. In actual instaUations rectified alternating current is em-... 

How many transfer units can the actual cooling tower or proposed new cooling tower actually perform ... 

Oxidative stability is highly important because it deals with the degradation of polymers under actual performance conditions. Oxidative stability, as applied to urethanes, refers to the combination of oxygen and heat or oxygen and light that causes degradation of urethanes. 

Another area to eonsider is heat exehanger effieieney. The concept of effieieney is to compare the actual performance of a piece of equipment with the ideal performanee (i.e., the maximum potential heat transfer). The maximum heat transfer possible is established by the stream that has the minimum heat eapaeity. That is the minimum value for the produet of stream mass flowrate and speeifie heat. This stream would, for maximum heat transfer, leave the exehanger at the inlet temperature of the other stream. In terms of the hot stream, the effieieney ean be stated as ... 

Contaminants can be deposited on the surface of or can permeate PPE and other equipment. The longer a contaminant stays in contact with an object, the greater the probability and extent of permeation. Minimizing contact time is one of the most important objectives of a decontamination program. This is why contact time with hazardous material should be taken into consideration when considering different methodologies in the actual performance of the task itself... 

The human error probabilities estimated for a given task can now be modified to reflect the actual performance situation. For example, if the labeling scheme at a particular plant is very poor, the probability should be increased towards an upper bound. If the tagging control system at a plant is particularly good, the probability for certain errors should be decreased toward a lower bound. 

Provide visual evidence of required performance against actual performance at work locations. 

Finally, failure analysis is the process of comparing actual performance with the desired performance. Thus, failure analysis is a nontrivial part of the structural design process. Facets of failure analysis including what failure means for a structure are addressed in Section 7.6 on Design Requirements and Design Failure Criteria. 

Discussions and interviews with the task experts can be supplemented with observations of their actual performance, for example, taking notes on certain aspects of the task or taking video or audio recordings. Observational techniques can reveal information that may be difficult to acquire in any other way. Detailed physical task performance data can be recorded, and major environmental influences (e.g., noise, light, interruptions) can all be faithfully represented. Observations can also provide an insight into the way that the team members communicate, allocate job responsibilities, and make use of operating procedures and other resources. 

This assumption is based partly on experimental evidence that shows a log-linear relationship between the evaluation of the factors affecting performance on maintenance tasks, and actual performance on the tasks, Pontecorvo (1965). In order to calculate the constants A and B in the equation, at least two tasks with known SLIs and error probabilities must be available in the set of tasks being evaluated. 

At C, change procedures to reflect actual performance, provide checklists, alter worker s perception of the importance and consequences of leaving valves open, and improve the supervision of procedures. Some form of lock system would be of benefit... 

The treatment follows my discussion of the it n spectra in Chapter 8, I actually performed a CIS calculation on pyridine within the ZDO scheme. If the ground state configuration is... 

The introduction of various empirical corrections, such as scale factors for frequencies and energy corrections based on the number of electrons and degree of spin contamination, blurs the distinction between whether they should be considered ab initio, or as belonging to the semi-empirical class of methods, such as AMI and PM3. Nevertheless, the accuracy tiiat tiiese methods are capable of delivering makes it possible to calculate absolute stabilities (heat of formation) for small and medium sized systems which rival (or surpass) experimental data, often at a substantial lower cost than for actually performing the experiments. 

The focus of codes and standards will shift from specifying the installation of prescriptive measures to the actual performance of the final building. This shift... 

Figures 3-36A, 3-36B, and 3-36C represent typical and actual performance curves showing discharge total head (head pressure at pump outlet connection for any fluid), required minimum water horsepow er (for pumping water), and capacity or pumping volume of the pump (for any fluid) for several impeller diameters that would fit the same case (housing). In addition the important NPSHr (net positive suction head required by the pump) charac-...

There are many design features and styles of safety relief valves, such as flanged ends, screwed ends, valves fitted internally for corrosive service, high temperature service, cryogenic service/low temperatures, with bonnet or without, nozzle entrance or orifice entrance, and resistance to discharge piping strains on body. Yet most of these variations have little, if anything to do with the actual performance to relieve overpressure in a system/vessel. 

Note, most manufacturers tables or charts give SCFH capacities at 14.7 psia and 60°F, and these must be corrected by the gas laws to the artwa/volume at flowng conditions in order to represent the actual performance of the system. The tables or charts of the manufacturers read in SCFH for selected relief device setting and for tank pressure, expressed as air at SCFH (see Figures 7-37A and 37B). 

The actual performance curves of figures 12-61 and 12-61A-E represent a typical presentation from a manufacturer. The rated design point is established at 100% of the rated speed then other expected performances at lower or... 

The essence of a plant engineering contract will be that the plant actually performs to the criteria laid down in the design, and this must be established before a Practical Completion Certificate is even considered. Tests will need to be made to the plant, and then it will be commissioned by the contractor and left in a condition whereby it can be operated as specified. When the work within the contract is complete, a certificate should be issued by the client (or employer) to the contractor. The architect or consulting engineer acting as agent normally performs this duty. 

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