Failure type

HFAM has 20 groups of factors instead of the 10 general failure types of the TRIPOD approach. The reason for this is that all of the 10 TRIPOD GFTs would be applied in all situations, even though the actual questions that make up the factors may vary. In the case of HFAM, it would be rare to apply all of the factors unless an entire plant was being evaluated. HFAM uses a screening process to first identify the major areas vulnerable to human error. The generic factors and appropriate job specific factors are then applied to these areas. For example, control room questions would not be applied to maintenance jobs. 

Another link exists between the PIF concept and the sociotechnical assessment methods described in Section 2.7 The checklists used in the TRIPOD methodology are essentially binary questions which evaluate whether the sets of PIFs making up each of the general failure types are adequate or not. The hierarchical sets of factors in HRAM are essentially PIFs which are expressed at increasingly finer levels of definition, as required by the analyst. The audit tool which forms MANAGER also comprises items which can be regarded as PIFs which assess both management level and direct PIFs such as procedures. 

Although failures are recorded as time related or demand related, the distinction between the two failure types is not always clean cut. The total failures on any piece of equipment are usually a combination of some that are time dependent and some that are demand related. In other words, a piece of equipment that fails on demand may already be in a failed state when the demand arrives, or the demand may actually cause the failure. 

Fig. 8.29 Causes of failure and failure types investigated by a large chemical company in the...

In high-pressure boilers, there are three types of on-load corrosion acidic chloride, neutral chloride/dissolved oxygen, and caustic attack. The first and second (once it becomes established) are brittle and thick-walled and are accompanied by hydrogen damage which can lead to failure within a few hundred hours. Caustic attack tends to produce a gouged appearance of the metal due to extensive wastage. The morphology is fairly characteristic of the failure type. Acidic chloride forms hard, laminated oxide, whilst, with caustic attack, the oxide is often soft, and, as it is easily removed, may be absent. 

Type A HE is induced by acute liver failure, Type B results from portal-systemic bypass without intrinsic liver disease, and Type C occurs with cirrhosis. HE may be classified as episodic, persistent, or minimal. 

Since an understanding of the importance of any one process contributing to the failure in thermoplastics and the control over these processes is only partly attainable, a knowledge and understanding of the nature of endurance Hmits is of extreme importance for successful use of plastics, in particular engineered thermoplastics [27]. In terms of the failure type, polymer fracture may occur as a rapid extension of an initial defect, plastic flow of the matter and the thermally activated flow of the macromolecules. In all these cases, however, fracture is a localized phenomenon characterized by a large inhomogeneity of deformations. 

Chronic diseases caused by physical inactivity and inappropriate diet consumption are epidemic in modem Western society. Chronic diseases develop over a lifetime, with clinical sequelae occurring many years after the underlying pathogenesis of the disease has occurred. As we move ahead in the 21st century, cardiovascular diseases (i.e., coronary artery disease, hypertension, stroke, and heart failure), type 2 diabetes, metabolic syndrome, and cancer are the leading killers in Western society and are increasing dramatically in developing nations. 

Javaheri S, Parker TJ, Liming JD, Corbett WS, Nishiyama H, Wexler L, Roselle GA (1998) Sleep apnea in 81 ambulatory male patients with stable heart failure. Types and their prevalences, consequences, and presentations. Circulation 97 2154—2159... 

One effective way of dealing with experimental errors is to build a predictive model and score the screening results through the model, then to look at discrepancies between the experimental screening result and the model prediction. Often the highly potent but mechanical failure type of false negatives or false positives... 

In an ideal world we d make perfect products and provide flawless service, but that s not reality. You will have to choose which imperfections you ll try to prevent, and which ones you can let go. For instance, we could approach our alarm system example by focusing on the failure-type mistakes first, since the consequences of an error in this realm are more severe than for the false positives. 

In contrast, type II hepatotoxicity is associated with massive centrilobular liver cell necrosis that can lead to fulminant liver failure. Type II hepatotoxicity is characterized by fever, jaundice, and very high serum transaminase levels. It may be immune-medi-ated and is thought to occur in genetically predisposed individuals. The incidence of type II hepatotoxicity 1 35 000 with one exposure to halothane and... 

Polymer modified lightweight cement mortar Pull-out adhesion strength (MPa) Failure type... 

FIG. 5—Ratio of steel bond strength of RPC in comparison with RC and HSM. TAB LE 6—Steel bond strength and failure type of RPC in comparison with RC and HSM. 

Failure Type Split Failure Split Failure Split Failure Split Failure... 

Failure Type Bond Failure Steel Break off Steel Break off Bond Failure... 

There were three different failure modes in this slant shear test. The failure type for RC/RC specimens was interface failure. The failure modes for RPC/RPC specimens included repair material failure and substratum failure. The failure modes for HSM/RC and RPC/RC specimens were interface failure or substratum failure. RC and HSM specimens have relatively lower concrete bond strength, while RPC specimens still have relatively higher values after 1000 freeze-thaw cycles. 

Failure Type Substratum Failure Interface Failure ... 

An important aspect of the efficiency of inhibited plastics is the stock of Cl in the polymer matrix. If the anticorrosion system is designated for longterm operation, a moment when the Cl stock appears to be fully exhausted inevitably arrives. Naturally, this substantially lowers the effectiveness of the anticorrosion system, although does not necessarily lead to failure. Types of rust-inhibiting plastics such as coatings and preserving films retain their barrier properties even after volatilization or wash-out of the inhibitors and continue to insulate metal goods from the hostile environment. 

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