3,211 research outputs found
Fiber optic frequency transfer link
A reference frequency distribution system is disclosed for transmitting a reference frequency from a reference unit to a remote unit while keeping the reference frequency at the reference unit and the remote unit in phase. A fiber optic cable connects the reference unit to the remote unit. A frequency source at the reference unit produces a reference frequency having an adjustable phase. A fiber optic transmitter at the reference unit modulates a light beam with the reference frequency and transmits the light beam into the fiber optic cable. A 50/50 reflector at the remote unit reflects a first portion of the light beam from the reference unit back into the fiber optic cable to the reference unit. A first fiber optic receiver disposed at the remote unit receives a second portion of the light beam and demodulates the reference frequency to be used at the remote unit. A second fiber optic receiver disposed at the reference unit receives the first portion of the light beam and demodulates a reference frequency component. A phase conjugator is connected to the frequency source for comparing the phase of the reference frequency component to the phase of the reference frequency modulating the light beam being transmitted from the reference unit to maintain a conjugate (anti-symmetric) relationship between the reference frequency component and the reference frequency modulating the light beam where virtually no phase difference exists between the phase of the reference frequency component and the phase of the reference frequency modulating the light beam
Can Health Care Services Attract Retirees And Contribute to the Economic Sustainability of Rural Places?
The search for engines to power rural economic growth has gone beyond the traditional boundaries of the food and fiber sector to industries such as tourism and to schemes such as attracting metropolitan workers to commuter communities with rural amenities. A group that has been somewhat overlooked is retirees, who may wish to trade in urban or suburban life-styles for a more peaceful rural retirement. An industry that has been neglected is the health care industry, which is the most rapidly growing industry nationally and of particular interest to retirees and aging populations. This paper examines the importance of rural health care services in attracting migrants age 65+ to rural counties in Michigan. Results indicate that the number of health care workers has a positive effect on net in-migration, and that this effect is large and statistically significant for the 70+ age group. Implications for rural development strategies are discussed.elder migration, health care, rural development, Community/Rural/Urban Development,
Tribute to Richard N. Gardner
Richard Gardner was my valued mentor and colleague at Columbia University, beginning before I began teaching in 1984 and continuing well beyond his retirement in 2012. In the fall semesters from 1984 through 1989, we co-taught the survey course in International Law, using the Columbia textbook originally developed by Wolfgang Friedmann with other Columbia co-editors (which has remained the “Columbia book” over the years). Our first semester of teaching together coincided with the semester that Dick’s daughter, Nina, took the International Law class as a 2L at Columbia Law School (as his son, Tony, would also do, a few years later) – an experience they took fully in stride – although Dick later confessed in the pages of this Journal that he was a bit more worried about having his daughter in class than I realized at the time
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