177,301 research outputs found
Validation of a spatial-temporal soil water movement and plant water uptake model
Management and irrigation of plants increasingly relies on accurate mathematical models for the movement of water within unsaturated soils. Current models often use values for water content and soil parameters that are averaged over the soil profile. However, many applications require models to more accurately represent the soil–plant–atmosphere continuum, in particular, water movement and saturation within specific parts of the soil profile. In this paper a mathematical model for water uptake by a plant root system from unsaturated soil is presented. The model provides an estimate of the water content level within the soil at different depths, and the uptake of water by the root system. The model was validated using field data, which include hourly water content values at five different soil depths under a grass/herb cover over 1 year, to obtain a fully calibrated system for plant water uptake with respect to climate conditions. When compared quantitatively to a simple water balance model, the proposed model achieves a better fit to the experimental data due to its ability to vary water content with depth. To accurately model the water content in the soil profile, the soil water retention curve and saturated hydraulic conductivity needed to vary with depth
sj-docx-1-jiv-10.1177_08862605231163644 – Supplemental material for Women’s Disengagement Behaviors During Couple Conflict: Investigating Risk Indicators of Intimate Partner Violence
Supplemental material, sj-docx-1-jiv-10.1177_08862605231163644 for Women’s Disengagement Behaviors During Couple Conflict: Investigating Risk Indicators of Intimate Partner Violence by Molly R. Franz, Madeline Smethurst, Robin A. Barry, Hannah E. Cole and Casey T. Taft in Journal of Interpersonal Violence</p
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Alternatives to Semitones and Quartertones: Music-Theoretical Suggestions
Thanks to free software synthesisers that support custom tuning files, it is now possible for a massive number of people to experiment with alternatives to semitones and quartertones. Indeed, contemporary musicians are not forced to choose 12-tone equal temperament or 24-tone equal temperament. I begin this article with a critique of 24-tone equal temperament. I then present a variation on the well-known whole-tone scale plus new symmetrical modes inspired by the French composer Olivier Messiaen. Finally, I show how one can map a little-known, non-octave scale by the German physicist Heinz Bohlen to a conventional, Halberstadt keyboard. Since one can only make symmetrical modes (modes à transpositions limitées) with an equal temperament, most of the musical intervals discussed in this article are approximations of frequency-ratios; they are not pure frequency-ratios.No Full Tex
sj-docx-2-jiv-10.1177_08862605231163644 – Supplemental material for Women’s Disengagement Behaviors During Couple Conflict: Investigating Risk Indicators of Intimate Partner Violence
Supplemental material, sj-docx-2-jiv-10.1177_08862605231163644 for Women’s Disengagement Behaviors During Couple Conflict: Investigating Risk Indicators of Intimate Partner Violence by Molly R. Franz, Madeline Smethurst, Robin A. Barry, Hannah E. Cole and Casey T. Taft in Journal of Interpersonal Violence</p
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
Both spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Numerical modelling of rows of discrete piles used to stabilise landslides under long-term conditions in clays
A literature review found no rigorous solution for the ultimate lateral pile-soil pressure ( ) in a soil characterised by a frictional failure criterion, and that the popular empirical methods to estimate give profiles with depth that differ significantly. Most existing solutions for the lateral pile capacity in a group are for soil characterised by an undrained shear strength failure condition. Plane strain and constant overburden finite difference analyses (in FLAC3D) were used to model flow of soil around a pile but did not appear to give sensible solutions for a frictional soil. The ultimate pile-soil line load from three-dimensional analysis in FLAC3D behaved as physically expected; passive wedges formed close to the surface giving lower normalised resistance than at greater depths. A number of parametric analyses were carried out using the three-dimensional model to investigate the variation in the ultimate pile-soil line load with the soil strength and pile-soil interface strength. Larger values of initial earth pressure coefficient K0 led to enhanced values of and the mechanisms for this was further investigated by analysing the soil stresses mobilised around the pile as the soil was pushed with the pile. Limit equilibrium pile failure mechanisms were developed from conditions of force and moment equilibrium for the pile based on failure in the soil. Pile limit equilibrium conditions were determined for three failure modes to understand the relationships between pile shear force, bending moment and pile embedment length ratio. Three-dimensional numerical (FLAC3D) models were used to verify the limit equilibrium failure mechanisms. The limit equilibrium equations were found to provide unconservative predictions for the force that the pile can provide to stabilise a slope, compared with the FLAC3D analysis. The program Alp (which models the pile as a beam on springs) gave results that were close to the limit equilibrium calculations. Three-dimensional FLAC3D models were modified to investigate the conditions over which the derived limit equilibrium pile failure mechanisms could reasonably be applied. The centre-to-centre pile spacing was varied from 1 d to 10 d, where d is the diameter of the pile, to understand the pile-soil interaction for a row of piles using the FLAC3D model. When the pile spacing was less than 2 d, the pile stabilising force was the same as for a solid retaining wall. Beyond about 4 d, the piles were found to act individually
Letter from R. R. Zellick, Assistant Trust Officer, Anglo California National Bank of San Francisco, to Joseph R. Goodman, October 2, 1942
Letter from R. R. Zellick, Assistant Trust Officer at The Anglo California National Bank of San Francisco, to Joseph R. Goodman, regarding property owned by Dave Tatsuno. Zellick mentions a dispute between current tenants and Tatsuno, and that Tatsuno has asked Goodman to help locate trustworthy tenants.Personal correspondence, organizational records, government documents, publications, and other papers created or collected by Joseph R. Goodman documenting the forced removal and incarceration of Japanese Americans during World War II, as well as organized resistance to incarceration. Included in the collection are records of the Japanese Young Men's Christian Association and the Japanese American Citizens' League in San Francisco, including papers of the Japanese YMCA's executive secretary Lincoln Kanai; Sakai family papers; Goodman's correspondence to and from Japanese American incarcerees, organizations opposing forced removal and incarceration of Japanese Americans, the War Relocation Authority, and others; publications, photographs, and ephemera from the Topaz Relocation Center, where Goodman taught high school; War Relocation Authority records and publications; and newspaper clippings, pamphlets, and reports about forced removal and incarceration created by various government, religious, and civic organizations, in California and nationwide
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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