endocrine system

Group of ductless glands that secrete hormones necessary for normal growth and development, reproduction, and homeostasis. The major endocrine glands are the hypothalamus, pituitary, pineal, thyroid, parathyroids, adrenals, islets of Langerhans in the pancreas, ovaries, and testes. Secretion is regulated either by regulators in a gland that detect high or low levels of a chemical and inhibit or stimulate secretion or by a complex mechanism involving the hypothalamus and the pituitary. Tumours that produce hormones can throw off this balance. Diseases of the endocrine system result from over- or underproduction of a hormone or an abnormal response to a hormone.

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Human-machine system is a system in which the functions of a human operator (or a group of operators) and a machine are integrated. This term can also be used to emphasize the view of such a system as a single entity that interacts with external environment.

A manual system consists of hand tools and other aids which are coupled by a human operator who controls the operation. Operators of such systems use their own physical energy as the power source.

Links

• Technical Committee on Human-Machine Systems of the International Federation of Automatic Control (IFAC)
• Center of Human-Machine-Systems, Technische Universität Berlin