Verification problems

As has been discussed previously, it became apparent during the negotiation of the CWC that, because of uncertainty about the number of facilities that would be declared under Schedules 1, 2 and 3 and as DOC facilities, as well as their relative risk to the object and purpose of the CWC, it would be impractical to attempt to develop rigid solutions in the Convention text. The nature of the practical verification problems involved would become apparent only in the course of implementation of the CWC. See Mathews, Intention of Article VI . 

Back-up scheduling, logging, recorded data verification, problem detection, deviation reporting Media labeling and storage (on-site, off-site)... 

Jiang, H. and Deng, L. A Bayesian approach to the verification problem applications to speaker verification. IEEE Transactions on Speech and Audio Processing 9(8) (2001), 874—884. 

Modification Cycle Models. These models give a sequence of steps to be carried out—they are usually oriented for corrective maintenance. The steps are of the form Problem Verification, Problem Diagnosis, Reprogramming and Rebuild, Baseline Verification, and Validation. 

Complexity of software (the verification problem). If it is difficult to specify large amounts of code, it is equally difficult to verify them in any meaningful way. To ensure software code can be verified, it must be written in a clear manner, and verification planning must be done with care to ensure that verification is comprehensive and auditable. 

In contrast to structure verification, structure elucidation requires each of the three important capabilities described above. The discussion of structure determination that follows is framed in terms of structure elucidation. However, it should be recognized that the computer aids for the prediction and comparison of spectral data described below, which are used to rank order a set of candidate structures, are equally applicable to structure verification problems. 

While Eq. III-18 has been verified for small droplets, attempts to do so for liquids in capillaries (where Rm is negative and there should be a pressure reduction) have led to startling discrepancies. Potential problems include the presence of impurities leached from the capillary walls and allowance for the film of adsorbed vapor that should be present (see Chapter X). There is room for another real effect arising from structural peiturbations in the liquid induced by the vicinity of the solid capillary wall (see Chapter VI). Fisher and Israelachvili [19] review much of the literature on the verification of the Kelvin equation and report confirmatory measurements for liquid bridges between crossed mica cylinders. The situation is similar to that of the meniscus in a capillary since Rm is negative some of their results are shown in Fig. III-3. Studies in capillaries have been reviewed by Melrose [20] who concludes that the Kelvin equation is obeyed for radii at least down to 1 fim. 

Another potential problem is due to rotor instability caused by gas dynamic forces. The frequency of this occurrence is non-synchronous. This has been described as aerodynamic forces set up within an impeller when the rotational axis is not coincident with the geometric axis. The verification of a compressor train requires a test at full pressure and speed. Aerodynamic cross-coupling, the interaction of the rotor mechanically with the gas flow in the compressor, can be predicted. A caution flag should be raised at this point because the full-pressure full-speed tests as normally conducted are not Class IASME performance tests. This means the staging probably is mismatched and can lead to other problems [22], It might also be appropriate to caution the reader this test is expensive. 

If data gathering is also computer-linked, then the problem is to check out the correctness of the program. Hand calculation of one rated point for How head, efficiency, and horsepower will serve as verification. 

Verification film has drawbacks that render it useless for some assemblies. For bonded assemblies with complicated tooling and/or multiple layers of adhesive, the additional thickness of the release film plies can cause the verification film to be non-representative of an actual bonded assembly. Details can be moved out of their normal positions Just enough to prevent them from fitting coirectly or tooling from performing correctly, resulting in false indications of problems... 

If an assembly is destructively inspected, the verification film is used to identify potential problem areas for particular attention. These areas and others randomly selected are cross-sectioned to determine bondline thickness (Fig. 22), bond details are peeled apart to inspect for voids and honeycomb core bonds are... 

At the corner (b, 2ho) of the region, five stress conditions apparently govern the behavior. However, the problem would be overspecified if all five conditions were imposed at the same time. Rather, three are specified and, subsequently, the remaining two are seen to be automatically satisfied thereby acting as a built-in verification of the numerical results. Numerical experimentation revealed that the choice of the three conditions is immaterial the remaining two are always satisfied. 

Table 44.6 is a vibration troubleshooting chart that identifies some of the common failure modes. This table provides general guidelines for interpreting the most common abnormal vibration profiles. These guidelines, however, do not provide positive verification or identification of machine-train problems. Verification requires an understanding of the failure mode and how it appears in the vibration signature. 

A quotation from another great man of the 17th century refers to the same problem. Spinoza wrote in 1674 Omnis determinatio est negatio , i.e., each determination comes from a negation. If we take negatio as a description of falsification, we come to the basis of Popper s theory. Only a falsification is a real advance, because only this, but not a verification, is final. 

Verification of the shape of the curve has been obtained with the collaboration of Dr. J. Sherman by the theoretical treatment of a somewhat similar problem (the effect of s-p hybridization of bond orbitals on interatomic distance). 

Expository-type laboratory activities will continue to be needed for the development of basic experimental skills of the students, despite their inefficiency in providing a realistic scientific environment and in promoting the use of higher-order cognitive skills. Even defenders of the conventiorral-type of laboratory and laboratory manrral do not claim that they are always wisely used, nor do they claim that they shorrldbe used exclusively (Ault, 2002 2004). However, the domirrant problem is that despite the fact that research has established the superiority of irrqrriry laboratory activities over verification laboratory activities, cookbook laboratory activities are still prevalent in many high school and college irrstitutions (Monteyne, Mark, Cracolice, 2004). ... 

Optical sensors and relay switches are used throughout the test routine for verification. For all possible problems, as well as the sequence in which they occur, the robot must recognize that there is a problem, define the problem, decide how best to resolve the problem, perform the necessary operations to overcome the problem, and enable the system to resume testing. This is an AI application area and a critical feature, mainly because the system operates unattended and measurements are taken overnight and during weekends. 

Finally, the value of extensive time-series records extends beyond the identification of a specific problem. Long-term time-series permits verification that decisions are effective (or not) solutions are, indeed, working (or not) and the ongoing costs and benefits of the given control program are assessed accurately. With proper design of what to measure, it can also assist in understanding the why or why not. 

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