The phrase "are designed and maintained" is correct and usable in written English.
It can be used when discussing the creation and ongoing upkeep of systems, products, or processes.
Example: "The software applications are designed and maintained to ensure optimal performance and user satisfaction."
Alternatives: "are created and upheld" or "are developed and supported".
Not only are Britain's Trident missiles in a common pool shared with the US and maintained in Kings Bay, Georgia, its nuclear warheads are designed and maintained at the Atomic Weapons Establishment at Aldermaston with the help of US know-how, as recently declassified documents on the UK-US Mutual Defence Agreement confirmed.
Some infrastructures, usually ore lines, are designed and maintained for even higher axle loads than those suggested above.
These findings infer that irrigation professionals first consider how well water is controlled and distributed project-wide and second how appropriately primary canals are designed and maintained.
One of them, written by Murray, Fred Manson, associate director of Heatherwick Studio, and Pam Alexander, who chairs the Covent Garden Market Authority, examines how the city's streets and public spaces can be designed and maintained to that end.
With others in the movement, their goal is to transform the Linux operating system, which has been designed and maintained by a rag-tag group of computer hackers, into a direct desktop competitor to Microsoft's Windows.
Created after the Northeast blackout in 1965, the council sets the rules of the road for transmission companies: how much electricity can safely run through a line, how much backup capacity must be on hand, how equipment should be designed and maintained.
Multicast services are more complex to be designed and maintained than broadcast services due to additional signaling exchange and content delivery authorization and management.
Moreover, multicast services are more complex to be designed and maintained than broadcast services, due to additional signaling, content delivery authorization and management, and required support of multicast streams in WiMAX subscriber stations (SSs) and mobile stations (MSs).
Their freedom and flexibility, allowing reliable transition from the beginning of the insurance contract until its end, and vice versa, should be designed and maintained by modern wireless services.
Acts of punitive deprivation must be imposed on each convicted offender without the comfort of believing, much less knowing, that the purposes for which the system of punishment was designed and maintained will really be advanced by inflicting a given punishment.
