Active redundancy

Active redundancy or hot standby The component has the same failure rate as if it was operating in the system. 

Action language, 131-132 Active redundancy, 1933 Active Server Pages (ASPs), 79 Active X controls, 76 Activities ... 

B. Both elements in active redundancy The availability gain is expressed as follows ... 

Romera, R., Valdes, J.E. Zequeira, R.I. 2004. Active redundancy allocation in systems, IEEE Transactions on Reliability 53, 313-318. 

However, implementation of cold-standby strategies is more sophisticated because of the meeting the requirements to detect failures as they occur and activate the redundant component. This is not necessary for active redundancy because all components will be never idle. In addition to its complex implementation due to diagnostic inspection and cost of such system, deploying of standby redundancy have been a poor choice in the vehicle context so far. However deploying active redundancy is very popular, a system design is required synchronistically implement active and stand-by redundancy in various parts of new mechatronic system in order to achieve certain level of reliability. 

The reliability design optimization has frequently been performed using dynamic programming and integer programming for active redundancy cases. 

The calculation of PFD for the system structure with active redundancy... 

Figure 5. Standby redundancy versus active redundancy in association with number of component.

Similar to approach given by Coit (Coit 2003) the analysis as demonstrated in figure 5, suggests that there is a maximal limit which the cold redundancy offers better reliability than active redundancy. Above of the maximal limit, the active redundancy will be eh-gible. Due to overall cost restraint (c=200), deploying more than two redundant components for each element is not considered in the given example. The maximum defined number of components within a subsystem has been defined 2. 

The network reliabUity is represented as a logical OR of all the paths acting in an active redundancy. A passive redundancy with imperfect switching would have been more realistic but more complicated to evaluate. There exist different techniques for computing Ax y(t) such as the inclusion-exclusion principle (Ru-bino, 1998) or the binary decision diagram (Rauzy, 1993) (Liudong, 2008). Here, the present paper takes into account the behavior of each sensor of WSN. For this reason, each boolean function of each monitored point... 

Actuation mode (manual/automatic) - automatic Flow rate (kg/s) - Proprietary Mode of operation (active/passive) - active Redundancy - Yes Self sufficiency (h) - Pumps Safety graded - No... 

Mode of operation (active/passive) Active Redundancy 3 x 100%... 

Actuation mode Automatic Flow rate (kg/seg) 1.0 Mode of operation Active Redundancy Pumps 2 100%... 

As the example in Fig. 3.18 shows, apart from achieving selectivity, biocatalysis also renders steps such as protection, deprotection, or activation redundant, thereby increasing atom-efficiency, reducing waste, and minimizing energy requirements. 

After the failure of PLCB2, nothing happens because it is in active redundancy with PLCBl. 

Stop in order to avoid the development of a harmful situation. A third possibility is to activate redundant equipment in order to bring the system to the desired goal. 

In the interests of availability, the centralised equipment is fault-tolerant, with active redundant l-out-of-2 and 2-out-of-3 hardware configurations used for nonsafety and safety portions of the system respectively. 

Active redundancy (W) and passive redundancy (SB) can be combined to increase the availability of the system (see Figure 1.34). In case of failure of a processing unit, the unit is put out of service and a reserve unit is inserted in the loop. This type of architecture is often put into place for systems with difficult access. 

The computer safety system consists of two units in hot redundancy, but without voter, and organized in a selective active redundancy scheme the two computers are powered, receive and process inputs, but only one actually provides a single output. 

A parallel system is characterized by two or more identical components. They are both active, although only one is ultimately needed to run the system. In this case the system fails only if both of the components fail. This system is also termed active redundancy. The probability of both failing is ... 

Full active redundancy is when any one of the two or three (or more) parallel units can satisfy the required function. 

Partial active redundancy is when, for example, two or three parallel units must continue to operate in order to satisfy the required function. 

Conditional active redundancy involves a voting system and is used in applications such as digital/analog data processing when there is no simple way of identifying a failure. 

Consider the following triplicated fully active redundant system of three identical generators ... 

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