Center for Appropriate Transport Center for Appropriate Transport The Center for Appropriate Transport (CAT) is a non-profit community center dedicated to bicycles and alternative transport located in Eugene, Oregon, United States. CAT holds publicly funded educational workshops for teaching youth from ages 12 to 21. Within the facility there is a public bicycle repair workspace and a bike machine-shop for the design and manufacture of special-purpose bikes, particularly cargo bikes and recumbents. There is also a bike museum on site, a bike rack-building workshop, and a sewing facility. CAT formerly held the offices of "Oregon Cycling" magazine, which ceased publishing in 2009. CAT is
Mode of a linear field Mode of a linear field In physics, a vector field is linear if it is a solution of a set of linear equations "E". For instance, in physics, the electromagnetic field in vacuum, defined in the usual (3 + 1)-dimensional space "S", obeys Maxwell's equations. A linear combination of electromagnetic fields, with constant, real coefficients, is a new field which obeys Maxwell's equations. The solutions of the linear equations are represented in a real vector space "M". A radius of "M", which represents proportional solutions, is called a "mode". A norm may be defined. For instance, in electromagnetism, it is