2,775 research outputs found
Knowledge modeling for software design
This paper develops a modeling framework for systems engineering that encompasses systems modeling, task modeling, and knowledge modeling, and allows knowledge engineering and software engineering to be seen as part of a unified developmental process. This framework is used to evaluate what novel contributions the 'knowledge engineering' paradigm has made and how these impact software engineering
Cruise Report W-45 : scientific activities undertaken aboard R/V Westward, Key West - Woods Hole, April 11 - May 23, 1979
The Strombus Expedition, Key West - Woods Hole, MA, April 11 - May 23, 1979This cruise report outlines the scientific activities for the
Strombus Expedition, the forty-fifth cruise of the R/V Westward.
These activities fall into two separate categories which, however,
serve each other: a traditional academic program offered purely
and directly for the students' scholastic benefit; and, a program
of research and student projects in which the students' skill and
drive and curiosity determined the scope and benefit of their
participation
Investigations of the potential performance characteristics of selected contact lubricants for applications in miniature slip-ring capsules of the type used in ST 124 M stabilized inertial guidance platforms Final technical report, 27 Mar. 1968 - 30 Apr. 1970
Performance characteristics of liquid and solid lubricants for contacts of miniature slip-ring capsule
Recent evolution of an active barrier beach complex : Popponesset Beach, Cape Cod, Massachusetts
Popponesset Spit, the barrier beach sheltering Popponesset Bay on Cape
Cod, Massachusetts, has experienced large changes in its
location and shape over the past thirty years. Concern by the public
over loss of this barrier beach and the associated recreational and wildlife
resources, as well as its storm-protection function, resulted in a number of
studies involving local, state and federal officials. The purpose of these
studies was to identify causes and future trends (Benoit and Donahoe, 1979)
and to identify engineering solutions to this instability (U.S. Army Corps of
Engineers, 1972; Camp, Dresser and McKee, 1981). For various reasons, these
studies were incomplete and stated some conclusions which were generally
misleading or incorrect. The purpose of the present study was to provide a
thorough reexamination of the geological problem at Popponesset Spit, to
dispel the misconceptions and to more rigorously document the large-scale
changes. The impetus for our concern over the beach was a desire to
contribute to an effective, rational management and utilization strategy for
this coastal region.Prepared for the Board of Seiectmen of the Town of Mashpee, Commonweaith, MA and for the Department of Commerce, NOAA Office of Sea Grant under Grant NA 80AA-0-00077
United We Serve: A Call To Universal Jewish Service
We have reached a turning point in American Jewish history. Now that large segments of our community are living successful, integrated lives, we have an opportunity to align ourselves behind service to enrich Jewish life and to effect prophetic change in the world. In Pirke Avot (Ethics of the Fathers), Rabbi Tarfon admonishes us, You are not obliged to finish the task, neither are you free to desist from it. The usual interpretation is that our task is bigger than any of us in terms of the quantity of work that must be done. Rabbi Tarfon\u27s dictum, however, also refers to the complexity of the task. We come to understand the critical interdependence of individuals, each bringing their own skills and varied perspectives to accomplish our people\u27s role in the covenant
Stripes of Partially Fluorinated Alkyl Chains: Dipolar Langmuir Monolayers
Stripe-like domains of Langmuir monolayers formed by surfactants with
partially fluorinated lipid anchors (F-alkyl lipids) are observed at the
gas-liquid phase coexistence. The average periodicity of the stripes, measured
by fluorescence microscopy, is in the micrometer range, varying between 2 and 8
microns. The observed stripe-like patterns are stabilized due to dipole-dipole
interactions between terminal -CF3 groups. These interactions are particularly
strong as compared with non-fluorinated lipids due to the low dielectric
constant of the surrounding media (air). These long-range dipolar interactions
tend to elongate the domains, in contrast to the line tension that tends to
minimize the length of the domain boundary. This behavior should be compared
with that of the lipid monolayer having alkyl chains, and which form spherical
micro-domains (bubbles) at the gas-liquid coexistence. The measured stripe
periodicity agrees quantitatively with a theoretical model. Moreover, the
reduction in line tension by adding traces (0.1 mol fraction) of cholesterol
results, as expected, in a decrease in the domain periodicity.Comment: 20 pages, 4 fig
Sparking a Renewed Jewish Commitment to Service
Where do Jews stand in relation to service and what might a Jewish commitment to service look like? By reflecting on historical Jewish understandings of service, we hope to gain perspective on the present and the need to rejoin our concepts of God, service, and worship. Such explorations can spark a radical transformation of our social and communal norms
Elasticity of an interfacial particle raft
We study the collective behaviour of a close packed monolayer of non-Brownian
particles at a fluid-liquid interface. Such a particle raft forms a
two-dimensional elastic solid and can support anisotropic stresses and strains,
e.g. it buckles in uniaxial compression and cracks in tension. We characterise
this solid in terms of a Young's modulus and Poisson ratio derived from simple
theoretical considerations and show the validity of these estimates by using an
experimental buckling assay to deduce the Young's modulus.Comment: 7 pages, 5 figure
Development of an Accelerated Test Design for Predicting the Service Life of the Solar Array at Mead, Nebraska
Potential long-term degradation modes for the two types of modules in the Mead array were determined and judgments were made as to those environmental stresses and combinations of stresses which accelerate the degradation of the power output. Hierarchical trees representing the severity of effects of stresses (test conditions) on eleven individual degradation modes were constructed and were pruned of tests judged to be nonessential. Composites of those trees were developed so that there is now one pruned tree covering eight degradation modes, another covering two degradation modes, and a third covering one degradation mode. These three composite trees form the basis for selection of test conditions in the final test plan which is now being prepared
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