901 research outputs found
On the Complexity of Case-Based Planning
We analyze the computational complexity of problems related to case-based
planning: planning when a plan for a similar instance is known, and planning
from a library of plans. We prove that planning from a single case has the same
complexity than generative planning (i.e., planning "from scratch"); using an
extended definition of cases, complexity is reduced if the domain stored in the
case is similar to the one to search plans for. Planning from a library of
cases is shown to have the same complexity. In both cases, the complexity of
planning remains, in the worst case, PSPACE-complete
Literature-based reading program for grade one
The study of reading as a process conducted in the last twenty-five years has furthered the understanding of emerging literacy and, as a result, has influenced instructional programs for children. One theoretical base created from this exploration has come to be known as the whole language concept (Goodman, 1986). Many instructional features are related to the implementation of the whole language concept in a school program. One of the major features is the development of a literature base. Children\u27s involvement in the reading process through works from the different genres offers many opportunities for children to relate to their reading experiences and to create their own ideas
The Amazon Flood Plain Forest Tree Maquira coriacea (Karsten) C.C. Berg: Aspects of Ecology and Management
Maquira coriacea is a commercial tree species growing throughout the Amazon flood plain forests. Densities up to 14/ha of individuals, >10 cm diameter at breast height (DBH) were observed, corresponding to a basal area of 2 m2/ha and a volume of 38 m3/ha. The primary period of fruiting coincided with the annual flooding, but fruits were also produced in other parts of the year. Seedlings with densities up to 150/m2 were concentrated around mother trees, and the stocks fluctuated much over the year due to mortality caused by flooding and wilting in dry periods. Growth data mainly from nine 1 ha permanent sample plots were used to develop models of the height-diameter relationship and diameter increment. These relationships indicated that the optimal felling limit for maximum volume production was 120-130 cm DBH, which can be obtained in 150-260 years. Since seed production has been observed in much smaller individuals, such diameter limits should not be detrimental to regeneration
Optical quenching and recovery of photoconductivity in single-crystal diamond
We study the photocurrent induced by pulsed-light illumination (pulse
duration is several nanoseconds) of single-crystal diamond containing nitrogen
impurities. Application of additional continuous-wave light of the same
wavelength quenches pulsed photocurrent. Characterization of the optically
quenched photocurrent and its recovery is important for the development of
diamond based electronics and sensing
Structure and Floristic Composition of Flood Plain Forests in the Peruvian Amazon. II. The Understorey of Restinga Forests
Structure and floristic composition of small trees and shrubs (1.5 m height to 10 cm diameter at breast height was described in two flood plain forests of the lower Ucayali river, Peruvian Amazon. The forests were of the high and low restinga type, on an annual average flooded around 1 and 2 months, respectively. The soils were nutrient rich entisols, and the vegetation forms closed high canopy forests with presence of emergents. A total of 25 permanent sample plots covering 0.64 ha were established. They were nested within six quadratic 1 ha permanent sample plots where large individuals (>10 cm DBH) were inventoried. Overall average density and basal area of the understorey were 4458 ha and 5.0 m2 /ha, respectively. The families of Moraceae, Leguminosae, Annonaceae, Euphorbiaceae, and Lauraceae were among the most important tree families, while important shrub and small tree families were Violaceae, Rubiaceae, Melastomataceae, and Olacaceae. Two hundred eight and 204 tree species were registered in the restinga forest overstories and understories, respectively. Fifty-six percent of the species were shared between the two forest strata, while around 22% were confined to each of them. Species present only in the understorey were predominantly shrubs or treelets, while some of the species with a presence only in the overstorey were probably early succession species about to disappear from the forests
Estructura y Composicion Floristica del Bosque de la Llanura Aluvial en la Amazonia Peruana: I. El Bosque Alto
Three peruvian flood plain forests adjacent to the Ucayali river were sampled using nine one hectare permanent sample plots in which stems exceeding 10 cm DBH were identified and measured. These plots have been measured 4 times during 1993-1997, and provide the basis for the results reported here. Three plots were established in each of the three forest types high restinga, low restinga, and tahuampa, characterized in part by and annual inundation of 1, 2 and 4 months per year, respectively. Stem density varies from 446 to 601 per ha, and the basal area ranges between 20-29 m2/ha. A total of 321 species were recorded in the nine hectare sample, with 88-141 species in each one hectare plot. Species composition indicated a relatively low similarity between the forest types. Plots with the longest flooding contained the most species, expressed both as per unit area as well as per 1 000 stems. The flood plain forests contain fewer tree species than the non-flooded terra firme forest. In all three forests Legminosae, Euphorbiaceae, Annonaceae and Lauraceae, are important. The Moraceae family is conspicuous in both high restinga, as is Rubiaceae in low restinga. Lecythidaceae, Sapotaceae, and Chrysobalanaceae exhibit relatively high values in the tahuampa forest. High species importance values are obtained for Maquira coriacea, Guarea macrophylla, Terminalia oblonga, Spondias mombin, Ceiba pentandra, Hura crepitans, Schweilera spp., Campsiandra angustifolia, Pouteria spp., Licania micrantha, Parinari excelsa, and Calycophyllum spruceanum. Among the species of smaller stature, Drypetes amazonica, Leonia glycicarpa, Theobroma cacao, and Protium nodulosum attain high values
Ulva fenestrata protein – Comparison of three extraction methods with respect to protein yield and protein quality
Seaweed is gaining attention as a possible alternative and sustainable source of proteins. This study investigates three protein extraction methods and their effect on protein yield and quality when applied to Ulva fenestrata. Two of the methods included alkaline extractions (pH-shifts); one version solubilizing the proteins at pH 8.5 and one solubilizing them at pH 8.5 followed by pH 12 (pH 8.5 + 12). The third method was a mechanical pressing, using a double screw press. All extraction methods were followed by isoelectric precipitation to concentrate the proteins. Extraction at pH 8.5 gave the significantly highest total protein yield after the isoelectric precipitation, followed by extraction at pH 8.5 + 12 and lastly mechanical extraction gave the lowest yield. Proteins extracted with both alkaline methods had a significantly higher solubility at pH 7 and pH 9, compared to proteins from the mechanical pressing. There were no significant differences between the three methods in total D/L-amino acid ratio. Amino acid cross-links measured as lysinoalanine (LAL) and lanthionine (LAN) where found in significantly higher amounts in alkali-extracted proteins compared to mechanically extracted, however not to a degree that expect to compromise functional or nutritional quality. Further, no significant difference in protein in vitro digestibility was found between extraction methods. In conclusion, results indicated that protein extraction at pH 8.5 can be recommended, especially regarding total protein yield and solubility of the final protein extract
Optimization-Based Layout Design
This article is the first in-depth examination of revocation of peace officer licenses for citizen abuse. Unlike the more familiar remedy of terminating the officer’s employment, license revocation, more commonly called decertification, has the advantage of disabling the officer from continuing to work in other departments within the state, just as occurs for myriad other professions and occupations. To determine what type of misconduct led to revocation, a file search was made of all revocations by the Florida Criminal Justices Standards and Training Commission during the time period October 1976 – October 1983. Florida was selected because it has been a national leader in decertification. Of the cases involving citizen abuse, the majority involved extorting money or sex in exchange for not arresting the citizen and demanding sex outright. None of the cases involved gathering evidence in violation of the Fourth Amendment and thus the exclusionary rule would not have come into play. The article concludes that it would therefore be inadvisable for the Supreme Court to rely on decertification as an effective remedy for Fourth Amendment violations
The COMPLEX reference framework for HW/SW co-design and power management supporting platform-based design-space exploration
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Measurement of the CMS Magnetic Field
The measurement of the magnetic field in the tracking volume inside the
superconducting coil of the Compact Muon Solenoid (CMS) detector under
construction at CERN is done with a fieldmapper designed and produced at
Fermilab. The fieldmapper uses 10 3-D B-sensors (Hall probes) developed at
NIKHEF and calibrated at CERN to precision 0.05% for a nominal 4 T field. The
precise fieldmapper measurements are done in 33840 points inside a cylinder of
1.724 m radius and 7 m long at central fields of 2, 3, 3.5, 3.8, and 4 T. Three
components of the magnetic flux density at the CMS coil maximum excitation and
the remanent fields on the steel-air interface after discharge of the coil are
measured in check-points with 95 3-D B-sensors located near the magnetic flux
return yoke elements. Voltages induced in 22 flux-loops made of 405-turn
installed on selected segments of the yoke are sampled online during the entire
fast discharge (190 s time-constant) of the CMS coil and integrated offline to
provide a measurement of the initial magnetic flux density in steel at the
maximum field to an accuracy of a few percent. The results of the measurements
made at 4 T are reported and compared with a three-dimensional model of the CMS
magnet system calculated with TOSCA.Comment: 4 pages, 5 figures, 15 reference
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