1,720,962 research outputs found
Development of national extent terrain attributes (tanz), soil water balance surfaces (swatbal), and environmental surfaces, and their application for spatial modelling of pinus radiata productivity across new zealand
No full textThe most widely distributed and commercially important forestry crop in New Zealand is Pinus radiata D. Don. Until recently foresters have focussed on maintaining plantation management systems that are highly productive, while remaining sustainable. However, the new era of reduced carbon emissions and carbon trading means forestry systems are now viewed as potential sinks for the sequestration of carbon. Never before has the need to quantify the productive capacity of New Zealand's plantation forests at the national extent been so great. Furthermore, regions of relatively low productivity may become increasingly desirable because these sites require lower capital outlay.
In this research, a series of spatial surfaces potentially useful in the modelling and mapping of forest productivity across the national extent of New Zealand have been developed. Modelled surfaces include 15 primary and four secondary terrain attributes; 13 shortwave radiation surfaces, topographically adjusted (one annual and 12 monthly surfaces); and 39 soil water balance model surfaces (one annual and 12 monthly surfaces for fraction of available root zone water storage, available root zone water storage, and drainage).
Terrain attributes were developed using a 25-m floating point DEM and are unique and currently the best comprehensive surfaces for the following reasons.
(1) Terrain attributes comprehensively encompass the entire country compared with previous piecemeal and site-specific surfaces.
(2) Terrain attributes were modelled using a macro-catchment concept that divides the New Zealand landscape into large, naturally draining catchments to avoid the modelling problems associated with edge effects at catchment boundaries.
(3) Upslope contributing areas were calculated by switching between an FD8 algorithm that modelled flow divergence in upland regions above defined stream channels and a D8 algorithm used in low-lying areas where modelling of flow convergence is appropriate.
(4) Where appropriate, terrain attributes were corrected for undesirable spurious sinks inherent in the 25-m floating point DEM, while retaining naturally occurring sinks in karst environments, depressional lakes and wetlands. This correction provided a continuous surface that modelled flow either to a sink or continuously across the surface until reaching the sea.
The soil water balance model, SWatBal, is a dynamic spatial model that can be updated over time as new and improved data become available. SWatbal calculates the fraction of available root-zone water content, available root-zone water content, and drainage for the P. radiata species at a 100-m resolution throughout New Zealand. SWatBal was applied in this study to derive monthly mean soil water balance values, but the model can easily be adjusted to calculate any spatial extent or period. A further advance of SWatBal is the development of reasoned and allocated virtual (RAV) rainfall data. RAV consist of 365 rainfall surfaces representing the normal rainfall distribution on a monthly basis. The advantage RAV data have over monthly mean rainfall is that rainfall distribution of an actual month is used, making the data realistic, rather than assuming constant rainfall across each day for a month.
A shortwave-radiation model was developed for New Zealand at a 25-m cell-size resolution utilising a national extent DEM and a latitude surface. This shortwave radiation model encompassed slope and aspect adequately while simultaneously accounting for the influence of terrain shading. As a model it has simplicity, flexibility, and minimal computation time and storage requirements.
A partial least squares (PLS) regression technique was used to develop the surfaces of (i) stem volume mean annual increment at age thirty years for a defined reference regime of 300 stems ha-1 (300 Index), and (ii) mean top height at age twenty (Site Index) using TANZ, SWatBal and other developed and existing New Zealand spatial datasets. Together, (i) and (ii) provided the basis for a spatial model of P. radiata productivity. Initially, the 300 Index and Site Index values were calculated for 1698 permanent sampling plot (PSP) locations. For cross validation purposes, 552 PSP sites were withheld from all modelling procedures. PLS regression was used to model and predict 300 Index and Site Index values using previously developed and some existing datasets including climate, landuse, terrain, and their environmental surfaces. Best models explained 58% and 67 % of the variance for 300 Index and Site Index, respectively. The PLS models were also used to develop quantitative productivity maps across the national extent of New Zealand. In addition, a regression kriging (RK) technique was used, where ordinary kriging (OK) of the PLS model residuals was undertaken to improve model outcomes by summing the PLS and OK surfaces. Cross validation showed that prediction precision increased for both the 300 Index and Site Index RK models. However, only Site Index predictions were considered less biased using the RK technique. Findings from the commonly used and relatively straight forward spatial interpolation technique, inverse distance weighting (IDW), were compared with those derived using the more complex RK, OK, and PLS techniques. Cross validation showed that all techniques performed better than their respective data means. OK, RK, and IDW techniques were similar in prediction precision with the IDW prediction precision best for the 300 Index, and RK best for the Site Index. However, OK predictions showed reduced prediction bias. Having stated that RK, OK, and IDW interpolation techniques provided overall better predictions than PLS, it is emphasised that cross validation locations only occur within currently forested landscapes. Beyond these forested regions PLS regression has an inordinate advantage over OK and IDW prediction techniques by utilising local environmental and landform information. Additionally, there is the potential of prediction improvement through the coupling of the PLS model with its kriged regression residuals. Indeed, the main purpose of producing the 300 Index and Site Index maps was to provide empirically based predictions of regions currently without forests as much as regions with forests through spatial interpolation of existing national extent observed PSP data. Possible drivers of P. radiata productivity across 14 broad LENZ-derived environmental regimes were also assessed. It was found that generally air temperature and water balance variables were the predominate drivers
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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