Search results

Filter

Filetype

Your search for "*" yielded 536256 hits

A Teaching Laboratory for Process Control

Laboratory experiments offer one way to introduce more realism into the education of automatic control. This paper describes a control laboratory and a sequence of experiments performed in the basic automatic control courses at Lund Institute of Technology. The laboratory is based on level control of two cascaded tanks. An Apple II computer is used to implement control laws and to provide graphics

Physical bounds and sum rules for high-impedance surfaces

High-impedance surfaces are artificial surfaces synthesized from periodic structures. The high impedance is useful as it does not short circuit electric currents and reflects electric fields without phase shift. Here, a sum rule is presented that relates frequency intervals having high impedance with the thickness of the structure. The sum rule is used to derive physical bounds on the bandwidth fo

Lake Urmia is disappearing

The present article is a translation—to Farsi—of an article by Dr. Ali Mirchi (postdoctoral research associate at the Department of Civil and Environmental Engineering, Michigan Technological University), Dr. Kaveh Madani (lecturer in Environmental Management at the Centre for Environmental Policy, Imperial College London) and Dr. Amir Aghakouchak (assistant professor at the Department of Civil an

Attention and tool-use in the evolution of language

It is argued that the capacity to focus attention is crucial for intentional communication. Intentional communication is goal-intended; directed at changing mental states and as a consequence behaviour; about a referential object common to sender and recipient; and about objects that may be context-and referent-independent. Three different kinds of attention is discerned: scanning, attention attra