12,985 research outputs found
Non-linear Pattern Matching with Backtracking for Non-free Data Types
Non-free data types are data types whose data have no canonical forms. For
example, multisets are non-free data types because the multiset has
two other equivalent but literally different forms and .
Pattern matching is known to provide a handy tool set to treat such data types.
Although many studies on pattern matching and implementations for practical
programming languages have been proposed so far, we observe that none of these
studies satisfy all the criteria of practical pattern matching, which are as
follows: i) efficiency of the backtracking algorithm for non-linear patterns,
ii) extensibility of matching process, and iii) polymorphism in patterns.
This paper aims to design a new pattern-matching-oriented programming
language that satisfies all the above three criteria. The proposed language
features clean Scheme-like syntax and efficient and extensible pattern matching
semantics. This programming language is especially useful for the processing of
complex non-free data types that not only include multisets and sets but also
graphs and symbolic mathematical expressions. We discuss the importance of our
criteria of practical pattern matching and how our language design naturally
arises from the criteria. The proposed language has been already implemented
and open-sourced as the Egison programming language
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GEO debris and interplanetary dust: fluxes and charging behavior
In September 1996, a dust/debris detector: GORID was launched into the
geostationary (GEO) region as a piggyback instrument on the Russian Express-2
telecommunications spacecraft. The instrument began its normal operation in
April 1997 and ended its mission in July 2002. The goal of this work was to use
GORID's particle data to identify and separate the space debris to
interplanetary dust particles (IDPs) in GEO, to more finely determine the
instrument's measurement characteristics and to derive impact fluxes. While the
physical characteristics of the GORID impacts alone are insufficient for a
reliable distinction between debris and interplanetary dust, the temporal
behavior of the impacts are strong enough indicators to separate the
populations based on clustering. Non-cluster events are predominantly
interplanetary, while cluster events are debris. The GORID mean flux
distributions (at mass thresholds which are impact speed dependent) for IDPs,
corrected for dead time, are 1.35x10^{-4} m^{-2} s^{-1} using a mean detection
rate: 0.54 d^{-1}, and for space debris are 6.1x10^{-4} m^{-2} s^{-1} using a
mean detection rate: 2.5 d^{-1}. Beta-meteoroids were not detected. Clusters
could be a closely-packed debris cloud or a particle breaking up due to
electrostatic fragmentation after high charging.Comment: * Comments: 6 pages, 4 postscript figures, in Dust in Planetary
Systems 2005, Krueger, H. and Graps, A. eds., ESA Publications, SP in press
(2006). For high resolution version, see:
http://www.mpi-hd.mpg.de/dustgroup/~graps/dips2005/GrapsetalDIPS2005.pd
Pitot pressure in hypersonic flow with condensation.
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76722/1/AIAA-6518-763.pd
Coastal Origin of Common Snook, Centropomus undecimalis, in Florida Bay
We used the elemental signatures of otoliths to investigate the coastal origin of common snook (Centropomus undecimalis) in Florida Bay, Florida and evaluate current management boundaries. We examined juvenile otoliths from Florida’s Atlantic and Gulf of Mexico (Gulf) populations and determined that there were significant differences in several elemental ratios (Mn/Ca, Cu/Ca, Sr/Ca, Ba/Ca). In addition, a discriminant function analysis (DFA) indicated a significant separation between the juveniles from each coast and otoliths were never misclassified by coast, indicating a distinct difference in their otolith chemistry. Using only juvenile otoliths to derive a calibration function, a separate DFA indicated that the adults from Florida Bay likely originated from both coasts of Florida in roughly equal proportions. Although these preliminary results contradict tagging studies, they concur with genetic studies suggesting that both east and west coast populations contribute to the common snook found in Florida Bay
Reclassification of ICD-9 Codes into Meaningful Categories for Oncology Survivorship Research
Background. The International Classification of Disease, ninth revision (ICD-9) is designed to code disease into categories which are placed into administrative databases. These databases have been used for epidemiological studies. However, the categories used in the ICD9-codes are not always the most effective for evaluating specific diseases or their outcomes, such as the outcomes of cancer treatment. Therefore a re-classification of the ICD-9 codes into new categories specific to cancer outcomes is needed. Methods. An expert panel comprised of two physicians created broad categories that would be most useful to researchers investigating outcomes and morbidities associated with the treatment of cancer. A Senior Data Coordinator with expertise in ICD-9 coding, then joined this panel and each code was re-classified into the new categories. Results. Consensus was achieved for the categories to go from the 17 categories in ICD-9 to 39 categories. The ICD-9 Codes were placed into new categories, and subcategories were also created for more specific outcomes. The results of this re-classification is available in tabular form. Conclusions. ICD-9 codes were re-classified by group consensus into categories that are designed for oncology survivorship research. The novel re-classification system can be used by those involved in cancer survivorship research
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