Materials used for manned space flight are tightly controlled to ensure the safety of the crewmembers. Significant changes to the economic environment as well as impact from environmental restrictions have resulted in material obsolescence that requires recertification or revalidation, increasing cost and risk to the program. This paper will review the impact this issue has had on the Shuttle E...

One of the negative side effects of the consumer society and the increasing number of consumer goods available to the average household is the intransparency of product quality, especially product lifetime. There are many examples on failing products and premature obsolescence. Often this phenomenon is related to companies’ profit maximization strategies (planned obsolescence) and consumer prot...

Abstract In this paper we study how the scientific production of a representative researcher develops over his/her career. Using Pontryagin’s maximum principle derive optimal capital accumulation life cycle scientist. particular, are able to identify two regimes human (say intensive versus normal) and characterize their optimality depending on initial level. The includes formal proof negative i...

Computer Science, with its rapid development, has been receiving considerable attention and support from Taiwan’s government. Because of its active performance on the international stage, the authors consider Computer Science a suitable research field to investigate issues regarding highly-cited papers. As the literature review reveals, most studies about highly-cited papers covered the applica...

Many systems that are required to be manufactured and supported for long time periods lack control over critical portions of their supply chains; these systems include: military, avionics, industrial controls, rail infrastructure. This results in the components and technologies that these products depend on becoming obsolete (and unavailable) long before the system’s demand for them is exhauste...

A GOOD DOCroR NEVER GRADUATES! MAY I present Dr. Obsolescing Smith and Dr. Competent Smith ? Both are qualified and registered to practise the healing art on the basis of existing legal requirements. Fifteen years ago both completed the first phase of their medical education and received their respective medical degrees. Dr. 0. Smith graduated finally and irrevocably. With joyous abandon he sev...