Is the phase of plane waves an invariant?

Based on the invariance of the phase of waves, plane waves was shown to propagate with negative frequencies in a medium which moves at superluminal speeds opposite to the propagation direction of plane waves. The validity of the invariance of the phase of plane waves was then called into question. A radical change of the conventional concept of plane waves is recently proposed to solve the problem of negative frequency of waves. Here, we point out flaws in that proposal. Thus, the validity of the invariance of the phase of plane waves remains questionable

What can be done to restore Pacific turtle populations?: The Bellagio blueprint for action on Pacific sea turtles

The Bellagio Blueprint for Action on Pacific Sea Turtles is an outcome of the Bellagio Conference on the Conversation and Sustainable Management of Sea Turtles organized jointly by the WorldFish Center and U.S. NOAA Fisheries. During 17-21 November, 2003, a multi-disciplinary group of 25 experts met in Bellagio, Italy to draft an Action Plan on Pacific Sea Turtles. The group recognized the serious state of sea turtle populations in the Pacific and the escalating nature of human threats to the turtles. However, after examining cases of successful sea turtle conservation programs from around the world and reviewing a broad suite of promising policy and management actions in the Pacific, they concluded that actions to save the threatened and endangered species were possible. The Blueprint urges protecting all nesting beaches, reducing turtle take in at-sea and coastal fisheries, stimulating Pan-Pacific policy actions and encouraging the sustainability of the traditional use of sea turtles. In addition to this description of the Blueprint, the experts are developing a full policy brief and other products for wide dissemination.Turtle fisheries, Nature conservation, Resource management, Nesting, Staff Contrib. No. 1726, Pacific Ocean,

Junction range finder

Electronic system locates interferences in radar reception. System utilizes well known frequency-modulated continuous-wave technique to locate objects with nonlinear impedances. FM transmitter generates signal through bandpass filter which eliminates higher order harmonics around carrier frequency