Machine-checked proofs of the design and implementation of a fault-tolerant circuit

A formally verified implementation of the 'oral messages' algorithm of Pease, Shostak, and Lamport is described. An abstract implementation of the algorithm is verified to achieve interactive consistency in the presence of faults. This abstract characterization is then mapped down to a hardware level implementation which inherits the fault-tolerant characteristics of the abstract version. All steps in the proof were checked with the Boyer-Moore theorem prover. A significant results is the demonstration of a fault-tolerant device that is formally specified and whose implementation is proved correct with respect to this specification. A significant simplifying assumption is that the redundant processors behave synchronously. A mechanically checked proof that the oral messages algorithm is 'optimal' in the sense that no algorithm which achieves agreement via similar message passing can tolerate a larger proportion of faulty processor is also described

Nanoscale gold pillars strengthened through dislocation starvation

It has been known for more than half a century that crystals can be made stronger by introducing defects into them, i.e., by strain-hardening. As the number of defects increases, their movement and multiplication is impeded, thus strengthening the material. In the present work we show hardening by dislocation starvation, a fundamentally different strengthening mechanism based on the elimination of defects from the crystal. We demonstrate that submicrometer sized gold crystals can be 50 times stronger than their bulk counterparts due to the elimination of defects from the crystal in the course of deformation

Precedent and Justice

Precedent is the cornerstone of common law method. It is the core mechanism by which the common law reaches just outcomes. Through creation and application of precedent, common law seeks to produce justice. The appellate courts\u27 practice of issuing unpublished, non-precedential opinions has generated considerable discussion about the value of precedent, but that debate has centered on pragmatic and formalistic values. This essay argues that the practice of issuing non-precedential opinions does more than offend constitutional dictates and present pragmatic problems to the appellate system; abandoning precedent undermines justice itself. Issuance of the vast majority of decisions as nonprecedential tears the justice-seeking mechanism of precedent from the heart of our common law system

Sediment management for Southern California mountains, coastal plains and shoreline

The Environmental Quality Laboratory at Caltech and the Shore Processes Laboratory at Scripps Institution of Oceanography have jointly undertaken a study of regional sediment balance problems in coastal southern California (see map in Figure 1). The overall objective in this study is to define specific alternatives in sediment management that may be implemented to alleviate a) existing sediment imbalance problems (e.g. inland debris disposal, local shoreline erosion) and b) probable future problems that have not yet manifested themselves. These alternatives will be identified through a consideration of economic, legal, and institutional issues as well as an analysis of governing physical processes and engineering constraints. The first part of this study (Phase I), which is currently under way, involves a compilation and analysis of all available data in an effort to obtain an accurate definition of the inland/coastal regional sediment balance under natural conditions, and specific quantitative effects man-made controls have on the overall natural process. During FY77, substantial progress was made at EQL and SPL in achieving the objectives of the initial Planning and Assessment Phase of the CIT/SIO Sediment Management Project. Financial support came from Los Angeles County, U.S. Geological Survey, Orange County, U.S. Army Corps of Engineers, and discretionary funding provided by a grant from the Ford Foundation. The current timetable for completion of this phase is Fall 1978. This report briefly describes the project status, including general administration, special activities, and research work as of January 1978

Russian manufacturing and the threat of ‘Dutch disease’: a comparison of competitiveness developments in Russian and Ukrainian industry

This paper examines the development of Russian industry in comparison with that of Ukrainian industry during 1995–2004 in an effort to ascertain to what extent, if any, Russian manufacturing showed signs of succumbing to ‘Dutch disease’. Ukraine and Russia began the market transition with broadly similar institutions, industrial structures and levels of technology, and the economic reforms implemented in the two countries were also similar, although Ukraine was reckoned to lag behind Russia in many areas. The main difference between them is Russia’s far greater resource wealth. It follows that differences in industrial development since 1991 may to some degree be attributable to differences in initial natural resource endowments. In short, Ukraine could provide a rough approximation of how a resource-poor Russia might have developed over the transition

Progress toward a cosmic dust collection facility on space station

Scientific and programmatic progress toward the development of a cosmic dust collection facility (CDCF) for the proposed space station is documented. Topics addressed include: trajectory sensor concepts; trajectory accuracy and orbital evolution; CDCF pointing direction; development of capture devices; analytical techniques; programmatic progress; flight opportunities; and facility development

Changes in the depository industry in Tenth District states

Recent development in Congress and the courts have focused attention on the relative roles of commercial banks, thrifts, and credit unions. As concern mounted last year about the state of the thrift deposit insurance fund, Congress required commercial banks to share the burden of recapitalizing the fund. In return, Congress promised to come up with a plan for merging the bank and thrift charters, a move the banking industry has long favored. About the same time, a federal appeals court ruled against a major source of credit union growth since the early 1980s - the acceptance of new members with a common bond different from the original members. The Supreme Court later agreed to hear the case, sparking a renewed debate in Congress about the proper role of credit unions in the financial system. ; These recent actions by Congress and the courts follow a decade and a half of dramatic changes in the depository industry in Tenth District states. Some of these changes have been due to shifts in laws and regulations. First, there has been a significant decline in the number of district depository institutions - a decline in which banks, thrifts, and credit unions have all shared. Second, total deposits have declined when adjusted for inflation or measured relative to economic activity. Third, the share of thrifts in total deposits has plummeted relative to that of banks and credit unions. And fourth, while banks, thrifts, and credit unions still specialize in different loans and investments, the three types of institutions do not look as different today as at the beginning of the 1980s. ; Such changes are important because they affect the thousands of depository institutions in the district and the supply of credit and other financial services to district households and businesses. With those effects in mind, Keeton and McKibbin show how the district depository industry has changed since 1979, explain the factors behind each change, and suggest what further changes may lie ahead.Banks and banking ; Credit unions ; Savings and loan associations ; Federal Reserve District, 10th

Bonding Lexan and sapphire to form high-pressure, flame-resistant window

Flammable materials have been studied in normal gravity and microgravity for many years. Photography plays a major role in the study of the combustion process giving a permanent visual record that can be analyzed. When these studies are extended to manned spacecraft, safety becomes a primary concern. The need for a high-pressure, flame-resistant, shatter-resistant window permitting photographic recording of combustion experiments in manned spacecraft prompted the development of a method for bonding Lexan and sapphire. Materials that resist shattering (e.g., Lexan) are not compatible with combustion experiments; the material loses strength at combustion temperatures. Sapphire is compatible with combustion temperatures in oxygen-enriched atmospheres but is subject to shattering. Combining the two materials results in a shatter-resistant, flame-resistant window. Combustion in microgravity produces a low-visibility flame; however, flame propagation and flame characteristics are readily visible as long as there is no deterioration of the image. Since an air gap between the Lexan and the sapphire would reduce transmission, a method was developed for bonding these unlike materials to minimize light loss