214 research outputs found
Rib waveguide to strip waveguide mode converter using local oxidation of silicon (LOCOS)
No full textA mode converter that goes from a rib waveguide to a strip waveguide has been demonstrated. The mode converter contains a 3-D taper fabricated using LOCOS. The demonstrated losses are 0.34 dB per coupler.United States. Defense Advanced Research Projects Agency (Air Force Contract FA8721-05-C-0002
Silicon photonics devices for integrated analog signal processing and sampling
No full textSilicon photonics offers the possibility of a reduction in size weight and power for many optical systems, and could open up the ability to build optical systems with complexities that would otherwise be impossible to achieve. Silicon photonics is an emerging technology that has already been inserted into commercial communication products. This technology has also been applied to analog signal processing applications. MIT Lincoln Laboratory in collaboration with groups at MIT has developed a toolkit of silicon photonic devices with a focus on the needs of analog systems. This toolkit includes low-loss waveguides, a high-speed modulator, ring resonator based filter bank, and all-silicon photodiodes. The components are integrated together for a hybrid photonic and electronic analog-to-digital converter. The development and performance of these devices will be discussed. Additionally, the linear performance of these devices, which is important for analog systems, is also investigated
"Overcoming America's Infrastructure Deficit, A Fiscally Responsible Plan for Public Capital Investment"
No full textCondemned bridges, dilapidated school buildings, contaminated water supplies, and other infrastructure shortcomings threaten American growth, productivity, and prosperity. S Jay Levy and Walter M. Cadette propose a plan for financing infrastructure projects that is designed to have minimal effect on the federal budget and to promote sound fiscal operation. Federal zero-interest mortgage loans to state and local governments for capital projects specified by Congress can cut the cost of such projects, achieve needed improvements in the nation's infrastructure, and thereby contribute to the American economy's future.
WDM laser transmitters for mobile free-space laser communications
No full textWe describe the performance of versatile high-performance multi-rate WDM laser transmitters using next-generation compact high-extinction-ratio power-efficient (CHERPe) transmitter designs. These leverage periodic time-frequency windowing of directly modulated laser signals to efficiently generate nearly ideal WDM waveforms with only mW-class drive power. facilitating WDM-channelization and providing straightforward access to many THz of available optical spectrum with low-bandwidth electronics. Furthermore, this approach can support scalable multi-rate operation with good power-and photon-efficiency and enable new architectural options. This approach is attractive for numerous applications and systems ranging from small airborne or CubeSAT-sized communication payloads to larger interplanetary lasercom platforms.Office of the Assistant Secretary of Defense for Research and Engineering (Contract FA8721-05-C-0002
Status of anadromous salmonids in Oregon coastal basins
No full textThomas E. Nickelson, Jay W. Nicholas, Alan M. McGie, Robert B. Lindsay, Daniel L. Bottom (Research and Development Section, Oregon Department of Fish and Wildlife), and Rodney J. Kaiser, Steven E. Jacobs (Ocean Salmon Management, Oregon Department of Fish and Wildlife).This archived document is maintained by the State Library of Oregon as part of the Oregon Documents Depository Program. It is for informational purposes and may not be suitable for legal purposes.Includes bibliographical references (pages 71-81).Mode of access: Internet from the Oregon Government Publications Collection.Text in English
America's Upside-down Doctrine of Education: Albert Jay Nock's Theory of What Has Gone Wrong — Or Is It Right?
No full textThe American system of education makes important and sometimes unjustified assumptions that were questioned and criticized nearly a hundred years ago by author and educational theorist Albert Jay Nock. This essay discusses Nock’s theory of American education and finds that certain of these assumptions stand greatly in need of the support of evidence
America's Upside-down Doctrine of Education: Albert Jay Nock's Theory of What Has Gone Wrong — Or Is It Right?
No full textThe American system of education makes important and sometimes unjustified assumptions that were questioned and criticized nearly a hundred years ago by author and educational theorist Albert Jay Nock. This essay discusses Nock’s theory of American education and finds that certain of these assumptions stand greatly in need of the support of evidence
Operation and Optimization of Silicon-Diode-Based Optical Modulators
No full textAn optical modulator in silicon based on a diode structure
has been operated in both forward and reverse bias. This modulator
achieves near state-of-the-art performance in both modes,
thereby making this device ideal for comparing the two modes of
operation. In reverse bias, the device has a VπL [V subscript pi L] of 4.0 V·cm and a
bandwidth of 26 GHz. In forward bias, the device is very sensitive,
a VπL [V subscript pi L] as low as 0.0025 V·cm has been achieved, but the bandwidth
is only 100 MHz. A new geometry for a reverse-bias device
is proposed, and it is predicted to achieve a VπL [V subscript pi L] of 0.5 V·cm.United States. Defense Advanced Research Projects Agency. Electronic and Photonic Integrated Circuit (EPIC) Program (Air Force Contract FA8721-05-C-0002) (Contract W911NF-04-1-0431)National Science Foundation (U.S.)Ida M. Green Fellowshi
...and Contractual Consent
No full textIn Part I, the author contends that when economists persistently ignore the importance of contractual consent, they are missing the crucial problem of legitimacy. In Parts II and IV, he responds to the criticisms of his consent theory of contract advanced by Jay Feinman and Dennis Patterson. Both Feinman and Patterson object to the enterprise in which the author and others are engaging, and he explains why each is wrong to dismiss the current debate over default rules. Finally, in contrast, in Part III the author shows how Steven Burton\u27s theory of default rules, which he finds most congenial, is quite compatible with his despite the fact that Burton thinks they disagree
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