1,355,709 research outputs found
Assessing actual evapotranspiration in irrigation districts using Landsat TM images and SEBAL model: Potential uses for irrigation monitoring
Satellite imagery allows the observation of large land stretches and the acquisition of worthwhile information that can be used efficaciously in agro-hydrologic systems. On the other hand, remotely sensed data coupled with energy balance models represent reliable tools to estimate actual evapotranspiration (ET).
Objective of the research was to propose a methodology to estimate ET by using Landsat TM images and surface energy balance, thus allowing the monitoring of current irrigation practices and/or possible vegetation stress.
The proposed methodology was applied in an irrigation district managed by “Consorzio di Bonifica Agrigento 3”, Castelvetrano, Sicily (Italy), in which water is distributed by a pressurized distribution network operating on-turn.
Satellite information retrieved by a set of Landsat TM images allowed to implement the surface energy balance model (SEBAL) in order to map the spatial distribution of instantaneous ET over two main crops (olives and grapevines), during irrigation seasons (from May to September) 2009 and 2010. These instantaneous values were then up-scaled to daily values based on the hypothesis of self-preservation of evaporative fraction. Finally, daily acquisitions were used to derive ET within longer time intervals, by assuming the by assuming proportionality to temporal dynamics of the reference evapotranspiration (ET0) computed using standard ground meteo-data.
With reference to the acquisition days, the comparison between SEBAL outputs and maximum daily crop evapotranspiration (ETc) estimated with the FAO 56 approach, showed notable stress levels for both the investigated crops, except for the images acquired in May, when significant rainfall occurred in both years. Moreover, measurements of eddy covariance fluxes collected by a tower located in the district within an olive orchard, evidenced the general reliability of daily ET retrieved by the model and consequently the validity of the self-preservation hypothesis applied to upscale instantaneous ET. Even if the applied methodology can be considered a valuable tool to monitor irrigation practices, the availability of cloud-free satellite images, as well as the temporal frequency of sensing, are critical issues for the proposed applications
Personalized Risk Schemes and Machine Learning to Empower Genomic Prognostication Models in Myelodysplastic Syndromes
Myelodysplastic syndromes (MDS) are characterized by variable clinical manifestations and outcomes. Several prognostic systems relying on clinical factors and cytogenetic abnormalities have been developed to help stratify MDS patients into different risk categories of distinct prognoses and therapeutic implications. The current abundance of molecular information poses the challenges of precisely defining patients’ molecular profiles and their incorporation in clinically established diagnostic and prognostic schemes. Perhaps the prognostic power of the current systems can be boosted by incorporating molecular features. Machine learning (ML) algorithms can be helpful in developing more precise prognostication models that integrate complex genomic interactions at a higher dimensional level. These techniques can potentially generate automated diagnostic and prognostic models and assist in advancing personalized therapies. This review highlights the current prognostication models used in MDS while shedding light on the latest achievements in ML-based research
Energy and Hydraulic Performance-Based Management of Large-Scale Pressurized Irrigation Systems
Improving energy and hydraulic performance of large-scale pressurized irrigation is
now perceived as a very pressing need, after large budgets have been allocated into systems
modernization. This paper tackles this priority area by developing a management oriented
multi-step methodology, that integrates different existing models, to sector the system accord
ing to the pressure requirements of the hydrants, and to regulate the pumping station for i) a
fixed and a variable pressure head control, and for ii) an enhanced performance. When applied
to an on-demand system in the Sinistra Ofanto irrigation scheme of Foggia (Italy), this
integrated approach showed potential for energy saving under the optimal scenario of 49 %,
and noticeable improvement in the system performance in terms of hydrant pressure heads, as
compared to the actual conditions. The monetary assessment demonstrates that the achieved
energy saving amounts to 23,636 Euros per irrigation season, 45 % among which are due to
sectorin
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
Variations on the Author
“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
AirEdge: A Dependency-Aware Multi-Task Orchestration in Federated Aerial Computing
Emerging edge computing (EC) systems are currently exploiting attaching portable edge devices on drones for
data processing close to the sources, to achieve high performance,
fast response times and real-time insights. To this end, existing EC
research has proposed several multiple drone-based edge deployments for various purposes, such as data caching, task offloading,
real-time video analytics, and computer vision. However, none of
them consider the ability of seamlessly integrating edge resources
running across multiple drones in a single pool, to holistically
manage and control these resources as well as to eliminate vendor
lock-in situations. This paper presents an intelligent resource
scheduling solution for a federated aerial EC system, called
AirEdge, which jointly considers task dependencies, heterogeneous resource demand and drones’ flight time. We propose a
multi-task execution time estimation and a dispatching policy, to
select the closest drone deployment having congruent flight time
and resource availability to execute ready tasks at any given time.
For the utilization of the drones’ attached edge resources, we propose a variant bin-packing optimization approach through gangscheduling of multi-dependent tasks that co-locates tasks tightly
on nodes to fully utilize available resources. Experiments on realworld data-trace from Alibaba cluster trace with information on
task dependencies (about 12,207,703 dependencies) and resource
demands show the effectiveness, fast executions, and resource
efficiency of our approac
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
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
Author, publisher and bookseller : a tripartite synergy in Nigerian book industry
This work is about the roles of Author, Publisher and Bookseller in Book development in
Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after
which it proceeded by defining who an author, a publisher, and a bookseller is and
expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in
the emerging Information Society. Furthermore, the various constraints to book
development were identified while the paper advised on how the Book Industry can be
further promoted in Nigeria. However, the paper concluded and made recommendations
on how the Book sector can help in enhancing scholarship in the country
The Thursday Murder Club: Launching a megabrand author - a publishing case study
In 2020, the Christmas book charts in the UK made headlines: Barack Obama’s eagerly awaited autobiography, The Promised Land, was beaten to the top spot by The Thursday Murder Club by Richard Osman, a debut cosy crime novel set in a retirement village. Not only did Osman’s book beat the former US president’s expected bestseller, it also broke records, becoming the fastest-selling debut crime novel of all time. Although Osman has a certain level of fame in the UK from his TV appearances on shows such as Pointless, his celebrity status does not entirely explain the novel’s huge sales. This article tracks the acquisition, publication, and promotion journey of The Thursday Murder Club in order to understand the industry and cultural context of its success and to interrogate the role of celebrity in the creation of author brands. The findings suggest that the unexpected scale of the success of the book owed to a number of factors, including in-depth editing by the novel’s agent, editor, and author to tighten up the plot, an extensive and strategic promotional campaign, the pandemic (which drove interest in the book’s genre and themes), and the quality of the writing. We find that the book’s success was accentuated by Osman’s celebrity status rather than being entirely reliant on it. This research adds to the growing scholarship on celebrity authorship by means of an in-depth case study and provides insight into the processes behind publishing a ‘celebrity’ book and launching a megabrand author
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