Control systems life cycle costs

Catalytic control devices are not necessarily inexpensive. For many applications, the cost of the catalyst itself can represent nearly 50% of the total investment for the control system. In addition, the performance of the catalyst usually degrades over time, gradually losing the ability to convert pollutants into harmless compounds. When the catalyst thus becomes deactivated, it must be regenerated or, more often, replaced with fresh catalyst. Because the catalyst is costly, the costs of catalyst deactivation can become a very significant fraction of the life-cycle costs of the control system. 

In practice, defining and controlling life-cycle costs is difficult. The future behavior of materials is often uncertain, as are the future uses of most systems, the environmental conditions to which they may be exposed, and the financial and economic conditions that influence relationships between present and future costs. An effective life-cycle cost analysis depends on having a reasonable range of possible alternatives that are likely to dehver equally satisfactory service over a given service life. Substantial obstacles to implementing life-cycle cost control in practice include ... 

Capital, operating, and environmental control costs and life-cycle analysis (Total Systems Approach)... 

A checklist analysis (CCPS, 1992) verifies the status of a system. It is versatile, easy and applicable at any life-cycle stage of a process. It is primarily used to show compliance with standards and practices by cost-effectively identifying hazards, chlorine Tar> <- liccklists provide commonality for management K.-, icw of hazard assessments. It may be used for controlling a proces.s from development to decommissioning. Approvals by appropriate authorities Cl i( V each stage of a project. 

To provide cost-effective safety engineering, the system and safety analysis and design process needs to consider the humans in systems—including those that are not directly controlling the physical processes—not separately or after the fact but starting at concept development and continuing throughout the life cycle of the system. 

Most of the system safety effort involves providing a service. That service is to identify, analyze, and control hazards as early in the life cycle as possible in order to produce cost-effectively a safer end product. Several products are produced as part of the system safety effort. These products (all documents) communicate and document risk information to management and provide a means of monitoring and auditing the effort. 

Bob Newnham proposed the idea of smart materials in the 70 . Since that we find research programs focused on systems with embedded actuators, sensors and controller units. Active structures proved beneficial, which for example arises from increased safety, reduced energy consumption, extended life cycle and unique performance. But as a non-series product they failed often by high production costs. In other words, extension of market share of active structures to commercial applications requires technology chains and designs, which are compatible with mass production, like typical found in care manufacturing. 

System Safety A subdiscipline of systems engineering that applies scientific, engineering, and management principles to ensure adequate safety, the timely identification of hazard risk, and initiation of actions to prevent or control those hazards throughout the life cycle and within the constraints of operational effectiveness, time, and cost (Stephenson 1991). The use of system engineering principles to provide a specified level of safety given the trade-offs involving cost, time, and the operations involved. 

As technological systems become more and more complex, it becomes increasingly difficult to identify safety hazards and control their impact. The cost is measured not only in dollars lost due to accidents, but also in lawsuits by employees injured on the job, degradation of the environment, loss of market share, and even ruined reputations. Engineers are finding that safety and risk touch upon every aspect of the engineering system design, operation, and disposal life cycle. 

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