2,124 research outputs found
AN EXAMPLE OF DEVELOPING COVARIATES FOR PROBLEMS IN PRECISION AGRICULTURE
Methodology for precision agriculture is, perhaps, too focused on methods that allow for spatial correlation in the ANOVA error term. While sound inference about differences between local yields can be computed, no understanding of what is driving these differences is achieved. A completely general form for a spatial model can include suitable covariates. Most research in precision agriculture includes gathering a variety of site-specific information. Through the presentation of the analysis of data from a published soybean [Glycine max (L.) Merr.] study, one specific type of covariate is developed - a duration index for soybean canopy light interception over the growing season. The relationship of the index to grain yield is reasonably well determined (R² = 0.82). We, therefore, suggest that the quest for modeling an appropriate covariate or covariates is primary. Treating spatial variation by other methods should only be used when the quest has failed
SUGGESTIONS FOR PRESENTING KRIGING RESULTS
Kriging maps are often part of the reported analyses in many environmental research studies including those our agency is working on in the area of precision/sustainable farming. All to often important details on the underlying variography and/or kriging procedures are omitted. Likewise the content and form of presenting kriging results vary greatly. Often features of the underlying variability are not readily seen. Instead of reviewing poor practice in current literature, we offer guidelines for reporting the methodology and presenting the results with the use of soil test phosphorus (STP) measures from a real world pasture study. Relevantly, the stationarity assumption for the variogram is argued; computational aspects for both the model and empirical variogram development are reported; and similarly, computational aspects for the kriging surface are reported. In short, enough detail is reported to understand and reproduce the analyses. Standard practice for presenting kriging results should include both the kriging estimates and the associated standard error map. Various planar and three dimensional plots are shown and discussed. Emphasis is on developing quality gray-scale planar maps for conventional publications. Ideally, for both recommended plots, patterns and unique features of the surfaces\u27 variability are revealed
A Comprehensive Trainable Error Model for Sung Music Queries
We propose a model for errors in sung queries, a variant of the hidden Markov
model (HMM). This is a solution to the problem of identifying the degree of
similarity between a (typically error-laden) sung query and a potential target
in a database of musical works, an important problem in the field of music
information retrieval. Similarity metrics are a critical component of
query-by-humming (QBH) applications which search audio and multimedia databases
for strong matches to oral queries. Our model comprehensively expresses the
types of error or variation between target and query: cumulative and
non-cumulative local errors, transposition, tempo and tempo changes,
insertions, deletions and modulation. The model is not only expressive, but
automatically trainable, or able to learn and generalize from query examples.
We present results of simulations, designed to assess the discriminatory
potential of the model, and tests with real sung queries, to demonstrate
relevance to real-world applications
Forgiveness Motives Among Evangelical Christians: Implications for Christian Marriage and Family Therapists
Therapists and researchers interested in forgiveness can learn from those who have experienced interpersonal wounds and have chosen to forgive. We interviewed 20 evangelical Christian forgivers, asking about motives for forgiveness. Transcripts were analyzed using qualitative methods. Five categories of motivation are presented: comfort, duty, relational, humility/empathy, and Christian beliefs. Respondents described multiple motives for forgiveness, often combining a desire for comfort or a sense of duty with their Christian beliefs. Four implications for Christian marriage and family therapists are discussed: Expect diversity, avoid moralistic views of motives, remember religious resources in the forgiveness process, and expect benefits, but not immediately
CHARACTERIZING THE STATISTICAL DISTRIBUTION OF ORGANIC CARBON AND EXTRACTABLE PHOSPHORUS AT A REGIONAL SCALE
Greater awareness of potential environmental problems has created the need to monitor total organic carbon (TOC) and extractable phosphorus (P) concentrations at a regional scale. The probability distribution of these soil properties can have a significant effect on the power of statistical tests and the quality of inferences applied to these properties. The objectives of this study were to: (1) evaluate the probability distribution of TOC and extractable P at the regional scale in three Major Land Resource Areas (MLRA), and (2) identify appropriate transformations that will result in a normal distribution. Both TOC and extractable P were non-normally distributed in all three MLRAs. Suggested power transformations did not result in normality, but a natural log and negative binomial transformation did produce distributions that met the assumptions of normality in most cases. Statistical analysis of TOC and extractable P data at the regional scale will need to take into account the non-normal distribution of these properties for accurate and precise estimates
Guidelines and the adoption of ‘lipid rescue’ therapy for local anaesthetic toxicity
Accepted versio
Particle-in-cell simulations of rf breakdown
Breakdown voltages of a capacitively coupled radio frequency argon discharge
at 27 MHz are studied. We use a one-dimensional electrostatic PIC code to
investigate the effect of changing the secondary emission properties of the
electrodes on the breakdown voltage, particularly at low pd values. Simulation
results are compared with the available experimental results and a satisfactory
agreement is found.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004,
Nice (France
Phenomenological and Microscopic Optical-Model Descriptions of 99 MeV 6-Li Scattering
This work was supported by National Science Foundation Grants PHY 76-84033A01, PHY 78-22774, and Indiana Universit
Errors in Heat Flux Measurement by Flux Plates of Contrasting Design and Thermal Conductivity
The thermal conductivity (λ) of soils may vary by a factor of about 4 for a range of field soil water contents. Measurement of soil heat flux (G) using a heat flux plate with a fixed λ distorts heat flow through the plates and in the adjacent soil. The objectives of this research were to quantify heat flow distortion errors for soil heat flux plates of widely contrasting designs and to evaluate the accuracy of a previously reported correction. Six types of commercially available heat flux plates with varying thickness, face area, and thermal conductivity (λm) were evaluated. Steady-state laboratory experiments at flux densities from 20 to 175 W m−2 were completed in a large box filled with dry or saturated sand having λ of 0.36 and 2.25 W m−1K−1 A field experiment compared G measured with pairs of four plate types buried at 6 cm in a clay soil with G determined using the gradient technique. The flux plates underestimated G in the dry sand by 2.4 to 38.5% and by 13.1 to 73.2% in saturated sand while in moist clay plate performance ranged from a 6.2% overestimate to a 71.4% underestimate. Application of the correction generally improved agreement between plate estimates and independent Gmeasurements, especially when λ \u3e λm, although most plate estimates were still significantly lower than the actual G Limitations of the correction procedure indicate that renewed effort should be placed on innovative sensor designs that avoid or minimize heat flow distortion and/or provide direct, in situ calibration capability
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