17,394 research outputs found
Compiling knowledge-based systems from KEE to Ada
The dominant technology for developing AI applications is to work in a multi-mechanism, integrated, knowledge-based system (KBS) development environment. Unfortunately, systems developed in such environments are inappropriate for delivering many applications - most importantly, they carry the baggage of the entire Lisp environment and are not written in conventional languages. One resolution of this problem would be to compile applications from complex environments to conventional languages. Here the first efforts to develop a system for compiling KBS developed in KEE to Ada (trademark). This system is called KATYDID, for KEE/Ada Translation Yields Development Into Delivery. KATYDID includes early prototypes of a run-time KEE core (object-structure) library module for Ada, and translation mechanisms for knowledge structures, rules, and Lisp code to Ada. Using these tools, part of a simple expert system was compiled (not quite automatically) to run in a purely Ada environment. This experience has given us various insights on Ada as an artificial intelligence programming language, potential solutions of some of the engineering difficulties encountered in early work, and inspiration on future system development
Fermion Number Conservation Isn't Fermion Conservation
A nonperturbative regularization of the Standard Model may have a
superficially undesirable exact global U(1) symmetry corresponding to exact
fermion number conservation. We argue that such a formulation can still have
the desired physics of fermion nonconservation, i.e. fermion particle creation
and annihilation by sphaleron transitions. We illustrate our reasoning in
massless axial QED in 1+1 dimensions.Comment: 3 pages to appear in the proceedings of Lattice '93, Dallas, Texas,
12-16 October 1993, comes as a single uuencoded postscript file (LaTeX source
available from the authors), ITFA 93-3
Factors Limiting Sexual Reproduction in Platanus Wrightii in Southeastern Arizona
Arizona sycamore (Platanus wrightii: Platanaceae) is a riparian tree of the southwestern United States and adjacent Mexico. It is failing to reproduce in certain canyons where mature, seed-producing trees of this species occur. Three hypotheses were tested to explain this reproductive failure: I) the presence of domestic cattle prevents reproduction, 2) seeds produced in certain canyons are inviable, and 3) annual flash floods destroy seedlings and young saplings but not the large, mature trees.
Canyons, either grazed or ungrazed by domestic animals, were surveyed for the presence of seedlings and young trees. In the laboratory, seeds were tested for viability, germinability in petri dishes, and emergence of seedlings from soil. Canyons which possessed seedlings and young saplings were censused before and after flooding. From these efforts, we conclude that reproductive failure of Arizona sycamore in certain canyons cannot be explained either by activities of domestic animals or by a lack of viable, germinable seeds. Flash flooding events in some canyons washed out the seedlings and saplings present, but left viable larger trees. We also found that a permanent, high water table was essential to propagule survival
Remark on lattice BRST invariance
A recently claimed resolution to the lattice Gribov problem in the context of
chiral lattice gauge theories is examined. Unfortunately, I find that the old
problem remains.Comment: 4 pages, plain TeX, presentation improved (see acknowledgments
On central tendency and dispersion measures for intervals and hypercubes
The uncertainty or the variability of the data may be treated by considering,
rather than a single value for each data, the interval of values in which it
may fall. This paper studies the derivation of basic description statistics for
interval-valued datasets. We propose a geometrical approach in the
determination of summary statistics (central tendency and dispersion measures)
for interval-valued variables
Visiting a Farm: An Exploratory Study of the Social Construction of Animal Farming in Norway and the Netherlands based on Sensory Perception
Most citizens in modern societies have little personal knowledge or experience of animal farming. This study explores the social construction of animal farming by studying how citizens perceive and evaluate modern farming after visiting a farm in real life. We wanted to understand how (non-farming) citizens develop an opinion of modern dairy farming when experiencing dairy farming in real life and practice, and how they translate what they see, smell and feel into an evaluative perception and mental image. We therefore conducted dairy farm visits with citizen panels in Norway and the Netherlands and asked the panel members to register what they saw, heard, smelled and felt and what they appreciated (or not) on the farm. The aspects that respondents registered could be grouped into four themes: the animals and their products, the rural landscape, farm practices and the farmer. When respondents described their experiences of these aspects on a specific farm, they appeared to look at them from three angles: modernity, tradition and naturality. Most respondents wanted farms to be modern, traditional as well as natural, but they were ready to negotiate and to accept compromises. Many respondents considered the farmer to be responsible for reconciling modernity, tradition and naturality. By taking different topics and issues into account and looking at animal farms from multiple angles, the respondentsâ developed a balanced and nuanced opinion of animal farming. The image that they constructed was not dualistic (arcadia versus factory) but pluralistic, thus at the same time more complex but also more flexible than expected. We expect that the development of a pluralistic image and balanced opinion was facilitated through the direct experience of dairy farming and farm life. The article starts with a theoretical analysis and aims to contribute to recent debates in rural sociology in two ways: 1) it studies how material experience and mental perception interact in the construction of an evaluative image of animal farming; and 2) it explores the social construction of animal farming as embedded into to the construction of nature, rurality and human-animal relationships. It concludes by discussing the contribution of the findings to the ongoing theoretical debate in this fiel
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