Fault serious

Here we have a situation where simple error by an operator produced serious consequences. The explosion was not, however, the operator s fault but was the result of bad design and lack of protective equipment. 

Condensate returns lines are often copper. Copper has good corrosion resistance to oxygen and carbon dioxide individually. When both gases are present in the condensate, copper is susceptible to corrosion. Copper picked up in the condensate system and returned to the boiler causes serious corrosion problems in the boiler and any steel feedwater and steam pipework. Boiler tubes should last for 25 years but can fail within one year in a mismanaged or ill-designed boiler system suffering from these faults. 

Both of these structures satisfy the formal valence rules for carbon, but each has a serious fault. Each structure shows three of the carbon-carbon bonds as double bonds, and three are shown as single bonds. There is a wealth of experimental evidence to indicate that this is not true. Any one of the six carbon-carbon bonds in benzene is. the same as any other. Apparently the fourth bond of each carbon atom is shared equally with each adjacent carbon. This makes it difficult to represent the bonding in benzene by our usual line drawings. Benzene seems to be best represented as the superposition or average of the two structures. For simplicity, chemists use either one of the structures shown in (30) usually expressed in a shorthand form (SI) omitting the hydrogen atoms ... 

One serious fault of these materials is that the presence of an electron-rich phenolic hydroxyl group inhibits free-radical polymerization. Thus, composite resins placed over them do not polymerize completely. 

Perhaps the most discouraging type of deviation from linearity is random scatter of the data points. Such results indicate that something is seriously wrong with the experiment. The method of analysis may be at fault or the reaction may not be following the expected stoichiometry. Side reactions may be interfering with the analytical procedures used to follow the progress of the reaction, or they may render the mathematical analysis employed invalid. When such plots are obtained, it is wise to reevaluate the entire experimental procedure and the method used to evaluate the data before carrying out additional experiments in the laboratory. 

A fault can be regarded as a not allowed deviation of at least one property or one characteristic parameter of the system compared to the normal operating conditions. The occurrence of a fault may have serious consequences in the process and may cause the facilities standstill, even to damage them. Several examples illustrating the gravity of the occurrence of sensor or actuators faults are reported in [25], [26], [62]. The fault detection refers to the determination of the presence of faults as well as their occurrence moment while the diagnosis is the determination of its amplitude and its behavior. 

For the water analysis, automation is clearly best achieved with an auto-injector for the mechanical handhng of the samples coupled with on-hne data capture, using the computer to analyse the peak data. Serious consideration was given to employing the very considerable in house automation experience to construct a purpose-built auto-injector. However, in the interests of a speedy implementation of the automatic system, it was decided to purchase a commercially available auto-injector and to concentrate the laboratory s efforts on the area of on-hne data capture. Interfacing the complete system assembly via a data communications network required the development of a special control device (commhox), which allowed the LGC hardware to run unattended hut provided an audible warning in event of a fault condition. 

This is usually indicated by a residence time distribution which rises to a maximum very much before o = 1 and is followed by a long tail due to the exchange of tracer with this stagnant region. This particular fault is especially serious in wash tanks and skim tanks where the ratio of height to diameter is small. 

The hazard and operability study (HAZOP) identifies a potential hazard. It provides little information on risk and consequences or its seriousness. However, by assessing the potential hazard, sometimes the designer may decide that the consequences of the hazard are either trivial or unlikely to be ignored. In certain instances, the solution is obvious and the design is modified. A fault tree analysis is useful where the consequences of the hazard are severe, or where its causes are many. The fault tree indicates how various events or combinations of events can give rise to a hazard. It is employed to identify the most... 

Polystyrene capacitors have exceptionally low tan S values (< 10 q, making them well suited for frequency-selective circuits in telecommunications equipment. Polymer capacitors are widely used for power-factor correction in fluorescent lighting units, and in start/run circuitry for medium-type electric motors used in washing machines, tumble-dryers and copying machines for example. They are also used in filter circuits to suppress radio frequencies transmitted along main leads. Such interference noise may originate from mechanical switches, furnace controllers and switch mode power supplies it not only spoils radio and television reception but can also cause serious faults in data-processing and computer equipment. 

From this viewpoint we must expect that all measurements of a, whether they are based on atomic physics, nuclear physics, or condensed matter physics, must agree with a obtained from QED (or more precisely the Standard Model) when their precisions are improved to 10-9, comparable to that of a(ae). If serious disagreement develops as precision of measurement improves, it might indicate a serious fault in some of these theories, possibly including quantum mechanics itself. See [12] for further discussions. 

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