70,158 research outputs found
Hope vs. Fear: The Debate Over a State Constitutional Convention
On November 7, 2017, New Yorkers will go to their polling places and receive ballots containing a thirteen-word referendum question: “Shall there be a convention to revise the constitution and amend the same?” That question appears on the ballot because the New York State Constitution commands that at least once every twenty years voters are asked whether or not to call a constitutional convention. The mandatory referendum reflects Thomas Jefferson’s belief that every generation the people should be given a chance to revise their basic law
Critique of Architectures for Long-Term Digital Preservation
Evolving technology and fading human memory threaten the long-term intelligibility of many kinds of documents. Furthermore, some records are susceptible to improper alterations that make them untrustworthy. Trusted Digital Repositories (TDRs) and Trustworthy Digital Objects (TDOs) seem to be the only broadly applicable digital preservation methodologies proposed. We argue that the TDR approach has shortfalls as a method for long-term digital preservation of sensitive information. Comparison of TDR and TDO methodologies suggests differentiating near-term preservation measures from what is needed for the long term.
TDO methodology addresses these needs, providing for making digital documents durably intelligible. It uses EDP standards for a few file formats and XML structures for text documents. For other information formats, intelligibility is assured by using a virtual computer. To protect sensitive information—content whose inappropriate alteration might mislead its readers, the integrity and authenticity of each TDO is made testable by embedded public-key cryptographic message digests and signatures. Key authenticity is protected recursively in a social hierarchy. The proper focus for long-term preservation technology is signed packages that each combine a record collection with its metadata and that also bind context—Trustworthy Digital Objects.
Saltation on Mars and expected lifetime of Viking 75 wind sensors
With the use of the wind-tunnel measurements of Bagnold and Zingg, a model is developed for estimating the parameters that describe the flux of sand on Mars. Application of this model to the sensor-breakage problem indicates that the expected lifetime on Mars of the wind sensors of the Viking 75 Meteorology Instrument System is about 40 earth years. This expected lifetime is adequate for both the primary Viking 75 mission and for a proposed extended mission
Commodity Prices Rock World Markets: Structural Shift or Short Term Adjustments?
International Relations/Trade,
A clarification of the Goodwin model of the growth cycle
We show that there is a difficulty in the original Goodwin model which isalso found in some more recent applications. In it both the labour share and theproportion employed can exceed unity, properties which are untenable. However, weshow that the underlying dynamic structure of the model can be reformulated toensure that these variables cannot exceed unity. An illustrative example extends theoriginal model, and we argue it is both plausible and satisfies the necessary unit boxrestrictions. We show that there is a difficulty in the original Goodwin model which isalso found in some more recent applications. In it both the labour share and theproportion employed can exceed unity, properties which are untenable. However, weshow that the underlying dynamic structure of the model can be reformulated toensure that these variables cannot exceed unity. An illustrative example extends theoriginal model, and we argue it is both plausible and satisfies the necessary unit boxrestrictions
Homelessness Counts: Changes in Homelessness from 2005 to 2007
In 2007, the National Alliance to End Homelessness released Homelessness Counts, establishing a 2005 baseline for measuring progress in the fight to end homelessness. This report is a follow up to that report. Here, we analyze the changes from 2005 to 2007, looking more closely at changes at the state level and among subpopulations
The free energies of formation of aqueous d-alanine, l-aspartic acid, and d-glutamic acid
The employment of thermodynamics in biochemistry has been restricted, until recently, to the use of first law data. In the last few years a beginning has been made in the application of the second law; i.e., of free energy data (1, 2). The development of this field is limited by the paucity of available free energy data. We have therefore undertaken the systematic determination of the free energies of formation of compounds which may be interesting in biochemistry or physiology
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